[v6,09/15] media: bcm2835-unicam: Add support for CCP2/CSI2 camera interface

Commit Message

Laurent Pinchart March 1, 2024, 9:32 p.m. UTC

From: Dave Stevenson <[e-mail]>

Add a driver for the Unicam camera receiver block on BCM283x processors.
It is represented as two video device nodes: unicam-image and
unicam-embedded which are connected to an internal subdev (named
unicam-subdev) in order to manage streams routing.

Signed-off-by: Dave Stevenson <[e-mail]>
Co-developed-by: Naushir Patuck <[e-mail]>
Signed-off-by: Naushir Patuck <[e-mail]>
Co-developed-by: Jean-Michel Hautbois <[e-mail]>
Signed-off-by: Jean-Michel Hautbois <[e-mail]>
Co-developed-by: Laurent Pinchart <[e-mail]>
Signed-off-by: Laurent Pinchart <[e-mail]>
---
Changes since v5:

- Move to drivers/media/platform/broadcom/
- Port to the upstream V4L2 streams API
- Rebase on latest metadata API proposal
- Add missing error message
- Drop unneeded documentation block for unicam_isr()
- Drop unneeded dev_dbg() and dev_err() messages
- Drop unneeded streams_mask and fmt checks
- Drop unused unicam_sd_pad_is_sink()
- Drop unneeded includes
- Drop v4l2_ctrl_subscribe_event() call
- Use pm_runtime_resume_and_get()
- Indentation and line wrap fixes
- Let the framework set bus_info
- Use v4l2_fwnode_endpoint_parse()
- Fix media device cleanup
- Drop lane reordering checks
- Fix subdev state locking
- Drop extra debug messages
- Move clock handling to runtime PM handlers
- Reorder functions
- Rename init functions for more clarity
- Initialize runtime PM earlier
- Clarify error messages
- Simplify subdev init with local variable
- Fix subdev cleanup
- Fix typos and indentation
- Don't initialize local variables needlessly
- Simplify num lanes check
- Fix metadata handling in subdev set_fmt
- Drop manual fallback to .s_stream()
- Pass v4l2_pix_format to unicam_calc_format_size_bpl()
- Simplify unicam_set_default_format()
- Fix default format settings
- Add busy check in unicam_s_fmt_meta()
- Add missing \n at end of format strings
- Fix metadata handling in subdev set_fmt
- Fix locking when starting streaming
- Return buffers from start streaming fails
- Fix format validation for metadata node
- Use video_device_pipeline_{start,stop}() helpers
- Simplify format enumeration
- Drop unset variable
- Update MAINTAINERS entry
- Update to the upstream v4l2_async_nf API
- Update to the latest subdev routing API
- Update to the latest subdev state API
- Move from subdev .init_cfg() to .init_state()
- Update to the latest videobuf2 API
- Fix v4l2_subdev_enable_streams() error check
- Use correct pad for the connected subdev
- Return buffers to vb2 when start streaming fails
- Improve debugging in start streaming handler
- Simplify DMA address management
- Drop comment about bcm2835-camera driver
- Clarify comments that explain min/max sizes
- Pass v4l2_pix_format to unicam_try_fmt()
- Drop unneeded local variables
- Rename image-related constants and functions
- Turn unicam_fmt.metadata_fmt into bool
- Rename unicam_fmt to unicam_format_info
- Rename unicam_format_info variables to fmtinfo
- Rename unicam_node.v_fmt to fmt
- Add metadata formats for RAW10, RAW12 and RAW14
- Make metadata formats line-based
- Validate format on metadata video device
- Add Co-devlopped-by tags

Changes since v3:

- Add the vendor prefix for DT name
- Use the reg-names in DT parsing
- Remove MAINTAINERS entry

Changes since v2:

- Change code organization
- Remove unused variables
- Correct the fmt_meta functions
- Rewrite the start/stop streaming
  - You can now start the image node alone, but not the metadata one
  - The buffers are allocated per-node
  - only the required stream is started, if the route exists and is
    enabled
- Prefix the macros with UNICAM_ to not have too generic names
- Drop colorspace support

Changes since v1:

- Replace the unicam_{info,debug,error} macros with dev_*()
---
 MAINTAINERS                                   |    1 +
 drivers/media/platform/Kconfig                |    1 +
 drivers/media/platform/Makefile               |    1 +
 drivers/media/platform/broadcom/Kconfig       |   23 +
 drivers/media/platform/broadcom/Makefile      |    3 +
 .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
 .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
 7 files changed, 2891 insertions(+)
 create mode 100644 drivers/media/platform/broadcom/Kconfig
 create mode 100644 drivers/media/platform/broadcom/Makefile
 create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
 create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c

Comments

Jacopo Mondi March 4, 2024, 5:12 p.m. UTC | #1

Hi Laurent

On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> From: Dave Stevenson <[e-mail]>
>
> Add a driver for the Unicam camera receiver block on BCM283x processors.
> It is represented as two video device nodes: unicam-image and
> unicam-embedded which are connected to an internal subdev (named
> unicam-subdev) in order to manage streams routing.
>
> Signed-off-by: Dave Stevenson <[e-mail]>
> Co-developed-by: Naushir Patuck <[e-mail]>
> Signed-off-by: Naushir Patuck <[e-mail]>
> Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> Co-developed-by: Laurent Pinchart <[e-mail]>
> Signed-off-by: Laurent Pinchart <[e-mail]>
> ---
> Changes since v5:
>
> - Move to drivers/media/platform/broadcom/
> - Port to the upstream V4L2 streams API
> - Rebase on latest metadata API proposal
> - Add missing error message
> - Drop unneeded documentation block for unicam_isr()
> - Drop unneeded dev_dbg() and dev_err() messages
> - Drop unneeded streams_mask and fmt checks
> - Drop unused unicam_sd_pad_is_sink()
> - Drop unneeded includes
> - Drop v4l2_ctrl_subscribe_event() call
> - Use pm_runtime_resume_and_get()
> - Indentation and line wrap fixes
> - Let the framework set bus_info
> - Use v4l2_fwnode_endpoint_parse()
> - Fix media device cleanup
> - Drop lane reordering checks
> - Fix subdev state locking
> - Drop extra debug messages
> - Move clock handling to runtime PM handlers
> - Reorder functions
> - Rename init functions for more clarity
> - Initialize runtime PM earlier
> - Clarify error messages
> - Simplify subdev init with local variable
> - Fix subdev cleanup
> - Fix typos and indentation
> - Don't initialize local variables needlessly
> - Simplify num lanes check
> - Fix metadata handling in subdev set_fmt
> - Drop manual fallback to .s_stream()
> - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> - Simplify unicam_set_default_format()
> - Fix default format settings
> - Add busy check in unicam_s_fmt_meta()
> - Add missing \n at end of format strings
> - Fix metadata handling in subdev set_fmt
> - Fix locking when starting streaming
> - Return buffers from start streaming fails
> - Fix format validation for metadata node
> - Use video_device_pipeline_{start,stop}() helpers
> - Simplify format enumeration
> - Drop unset variable
> - Update MAINTAINERS entry
> - Update to the upstream v4l2_async_nf API
> - Update to the latest subdev routing API
> - Update to the latest subdev state API
> - Move from subdev .init_cfg() to .init_state()
> - Update to the latest videobuf2 API
> - Fix v4l2_subdev_enable_streams() error check
> - Use correct pad for the connected subdev
> - Return buffers to vb2 when start streaming fails
> - Improve debugging in start streaming handler
> - Simplify DMA address management
> - Drop comment about bcm2835-camera driver
> - Clarify comments that explain min/max sizes
> - Pass v4l2_pix_format to unicam_try_fmt()
> - Drop unneeded local variables
> - Rename image-related constants and functions
> - Turn unicam_fmt.metadata_fmt into bool
> - Rename unicam_fmt to unicam_format_info
> - Rename unicam_format_info variables to fmtinfo
> - Rename unicam_node.v_fmt to fmt
> - Add metadata formats for RAW10, RAW12 and RAW14
> - Make metadata formats line-based
> - Validate format on metadata video device
> - Add Co-devlopped-by tags
>
> Changes since v3:
>
> - Add the vendor prefix for DT name
> - Use the reg-names in DT parsing
> - Remove MAINTAINERS entry
>
> Changes since v2:
>
> - Change code organization
> - Remove unused variables
> - Correct the fmt_meta functions
> - Rewrite the start/stop streaming
>   - You can now start the image node alone, but not the metadata one
>   - The buffers are allocated per-node
>   - only the required stream is started, if the route exists and is
>     enabled
> - Prefix the macros with UNICAM_ to not have too generic names
> - Drop colorspace support
>
> Changes since v1:
>
> - Replace the unicam_{info,debug,error} macros with dev_*()
> ---
>  MAINTAINERS                                   |    1 +
>  drivers/media/platform/Kconfig                |    1 +
>  drivers/media/platform/Makefile               |    1 +
>  drivers/media/platform/broadcom/Kconfig       |   23 +
>  drivers/media/platform/broadcom/Makefile      |    3 +
>  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
>  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
>  7 files changed, 2891 insertions(+)
>  create mode 100644 drivers/media/platform/broadcom/Kconfig
>  create mode 100644 drivers/media/platform/broadcom/Makefile
>  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
>  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e50a59654e6e..cc350729f467 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4002,6 +4002,7 @@ M:	Raspberry Pi Kernel Maintenance <[e-mail]>
>  L:	[e-mail]
>  S:	Maintained
>  F:	Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> +F:	drivers/media/platform/bcm2835/
>
>  BROADCOM BCM47XX MIPS ARCHITECTURE
>  M:	Hauke Mehrtens <[e-mail]>
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index 91e54215de3a..2d79bfc68c15 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
>  source "drivers/media/platform/amphion/Kconfig"
>  source "drivers/media/platform/aspeed/Kconfig"
>  source "drivers/media/platform/atmel/Kconfig"
> +source "drivers/media/platform/broadcom/Kconfig"
>  source "drivers/media/platform/cadence/Kconfig"
>  source "drivers/media/platform/chips-media/Kconfig"
>  source "drivers/media/platform/intel/Kconfig"
> diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> index 3296ec1ebe16..da17301f7439 100644
> --- a/drivers/media/platform/Makefile
> +++ b/drivers/media/platform/Makefile
> @@ -10,6 +10,7 @@ obj-y += amlogic/
>  obj-y += amphion/
>  obj-y += aspeed/
>  obj-y += atmel/
> +obj-y += broadcom/
>  obj-y += cadence/
>  obj-y += chips-media/
>  obj-y += intel/
> diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> new file mode 100644
> index 000000000000..cc2c9afcc948
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/Kconfig
> @@ -0,0 +1,23 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +config VIDEO_BCM2835_UNICAM
> +	tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> +	depends on ARCH_BCM2835 || COMPILE_TEST
> +	depends on PM
> +	depends on VIDEO_DEV
> +	select MEDIA_CONTROLLER
> +	select V4L2_FWNODE
> +	select VIDEO_V4L2_SUBDEV_API
> +	select VIDEOBUF2_DMA_CONTIG
> +	help
> +	  Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> +	  This is a V4L2 driver that controls the CSI-2 receiver directly,
> +	  independently from the VC4 firmware.
> +
> +	  This driver is mutually exclusive with the use of bcm2835-camera. The
> +	  firmware will disable all access to the peripheral from within the
> +	  firmware if it finds a DT node using it, and bcm2835-camera will
> +	  therefore fail to probe.
> +
> +	  To compile this driver as a module, choose M here. The module will be
> +	  called bcm2835-unicam.
> diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> new file mode 100644
> index 000000000000..03d2045aba2e
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> new file mode 100644
> index 000000000000..84775fd2fac5
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> @@ -0,0 +1,255 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +/*
> + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> + * Dave Stevenson <[e-mail]>
> + */
> +
> +#ifndef VC4_REGS_UNICAM_H
> +#define VC4_REGS_UNICAM_H
> +
> +#include <linux/bits.h>
> +
> +/*
> + * The following values are taken from files found within the code drop
> + * made by Broadcom for the BCM21553 Graphics Driver, predominantly in
> + * brcm_usrlib/dag/vmcsx/vcinclude/hardware_vc4.h.
> + * They have been modified to be only the register offset.
> + */
> +#define UNICAM_CTRL		0x000
> +#define UNICAM_STA		0x004
> +#define UNICAM_ANA		0x008
> +#define UNICAM_PRI		0x00c
> +#define UNICAM_CLK		0x010
> +#define UNICAM_CLT		0x014
> +#define UNICAM_DAT0		0x018
> +#define UNICAM_DAT1		0x01c
> +#define UNICAM_DAT2		0x020
> +#define UNICAM_DAT3		0x024
> +#define UNICAM_DLT		0x028
> +#define UNICAM_CMP0		0x02c
> +#define UNICAM_CMP1		0x030
> +#define UNICAM_CAP0		0x034
> +#define UNICAM_CAP1		0x038
> +#define UNICAM_ICTL		0x100
> +#define UNICAM_ISTA		0x104
> +#define UNICAM_IDI0		0x108
> +#define UNICAM_IPIPE		0x10c
> +#define UNICAM_IBSA0		0x110
> +#define UNICAM_IBEA0		0x114
> +#define UNICAM_IBLS		0x118
> +#define UNICAM_IBWP		0x11c
> +#define UNICAM_IHWIN		0x120
> +#define UNICAM_IHSTA		0x124
> +#define UNICAM_IVWIN		0x128
> +#define UNICAM_IVSTA		0x12c
> +#define UNICAM_ICC		0x130
> +#define UNICAM_ICS		0x134
> +#define UNICAM_IDC		0x138
> +#define UNICAM_IDPO		0x13c
> +#define UNICAM_IDCA		0x140
> +#define UNICAM_IDCD		0x144
> +#define UNICAM_IDS		0x148
> +#define UNICAM_DCS		0x200
> +#define UNICAM_DBSA0		0x204
> +#define UNICAM_DBEA0		0x208
> +#define UNICAM_DBWP		0x20c
> +#define UNICAM_DBCTL		0x300
> +#define UNICAM_IBSA1		0x304
> +#define UNICAM_IBEA1		0x308
> +#define UNICAM_IDI1		0x30c
> +#define UNICAM_DBSA1		0x310
> +#define UNICAM_DBEA1		0x314
> +#define UNICAM_MISC		0x400
> +
> +/*
> + * The following bitmasks are from the kernel released by Broadcom
> + * for Android - https://android.googlesource.com/kernel/bcm/
> + * The Rhea, Hawaii, and Java chips all contain the same VideoCore4
> + * Unicam block as BCM2835, as defined in eg
> + * arch/arm/mach-rhea/include/mach/rdb_A0/brcm_rdb_cam.h and similar.
> + * Values reworked to use the kernel BIT and GENMASK macros.
> + *
> + * Some of the bit mnenomics have been amended to match the datasheet.
> + */
> +/* UNICAM_CTRL Register */
> +#define UNICAM_CPE		BIT(0)
> +#define UNICAM_MEM		BIT(1)
> +#define UNICAM_CPR		BIT(2)
> +#define UNICAM_CPM_MASK		GENMASK(3, 3)
> +#define UNICAM_CPM_CSI2		0
> +#define UNICAM_CPM_CCP2		1
> +#define UNICAM_SOE		BIT(4)
> +#define UNICAM_DCM_MASK		GENMASK(5, 5)
> +#define UNICAM_DCM_STROBE	0
> +#define UNICAM_DCM_DATA		1
> +#define UNICAM_SLS		BIT(6)
> +#define UNICAM_PFT_MASK		GENMASK(11, 8)
> +#define UNICAM_OET_MASK		GENMASK(20, 12)
> +
> +/* UNICAM_STA Register */
> +#define UNICAM_SYN		BIT(0)
> +#define UNICAM_CS		BIT(1)
> +#define UNICAM_SBE		BIT(2)
> +#define UNICAM_PBE		BIT(3)
> +#define UNICAM_HOE		BIT(4)
> +#define UNICAM_PLE		BIT(5)
> +#define UNICAM_SSC		BIT(6)
> +#define UNICAM_CRCE		BIT(7)
> +#define UNICAM_OES		BIT(8)
> +#define UNICAM_IFO		BIT(9)
> +#define UNICAM_OFO		BIT(10)
> +#define UNICAM_BFO		BIT(11)
> +#define UNICAM_DL		BIT(12)
> +#define UNICAM_PS		BIT(13)
> +#define UNICAM_IS		BIT(14)
> +#define UNICAM_PI0		BIT(15)
> +#define UNICAM_PI1		BIT(16)
> +#define UNICAM_FSI_S		BIT(17)
> +#define UNICAM_FEI_S		BIT(18)
> +#define UNICAM_LCI_S		BIT(19)
> +#define UNICAM_BUF0_RDY		BIT(20)
> +#define UNICAM_BUF0_NO		BIT(21)
> +#define UNICAM_BUF1_RDY		BIT(22)
> +#define UNICAM_BUF1_NO		BIT(23)
> +#define UNICAM_DI		BIT(24)
> +
> +#define UNICAM_STA_MASK_ALL \
> +		(UNICAM_DL | \
> +		UNICAM_SBE | \
> +		UNICAM_PBE | \
> +		UNICAM_HOE | \
> +		UNICAM_PLE | \
> +		UNICAM_SSC | \
> +		UNICAM_CRCE | \
> +		UNICAM_IFO | \
> +		UNICAM_OFO | \
> +		UNICAM_PS | \
> +		UNICAM_PI0 | \
> +		UNICAM_PI1)
> +
> +/* UNICAM_ANA Register */
> +#define UNICAM_APD		BIT(0)
> +#define UNICAM_BPD		BIT(1)
> +#define UNICAM_AR		BIT(2)
> +#define UNICAM_DDL		BIT(3)
> +#define UNICAM_CTATADJ_MASK	GENMASK(7, 4)
> +#define UNICAM_PTATADJ_MASK	GENMASK(11, 8)
> +
> +/* UNICAM_PRI Register */
> +#define UNICAM_PE		BIT(0)
> +#define UNICAM_PT_MASK		GENMASK(2, 1)
> +#define UNICAM_NP_MASK		GENMASK(7, 4)
> +#define UNICAM_PP_MASK		GENMASK(11, 8)
> +#define UNICAM_BS_MASK		GENMASK(15, 12)
> +#define UNICAM_BL_MASK		GENMASK(17, 16)
> +
> +/* UNICAM_CLK Register */
> +#define UNICAM_CLE		BIT(0)
> +#define UNICAM_CLPD		BIT(1)
> +#define UNICAM_CLLPE		BIT(2)
> +#define UNICAM_CLHSE		BIT(3)
> +#define UNICAM_CLTRE		BIT(4)
> +#define UNICAM_CLAC_MASK	GENMASK(8, 5)
> +#define UNICAM_CLSTE		BIT(29)
> +
> +/* UNICAM_CLT Register */
> +#define UNICAM_CLT1_MASK	GENMASK(7, 0)
> +#define UNICAM_CLT2_MASK	GENMASK(15, 8)
> +
> +/* UNICAM_DATn Registers */
> +#define UNICAM_DLE		BIT(0)
> +#define UNICAM_DLPD		BIT(1)
> +#define UNICAM_DLLPE		BIT(2)
> +#define UNICAM_DLHSE		BIT(3)
> +#define UNICAM_DLTRE		BIT(4)
> +#define UNICAM_DLSM		BIT(5)
> +#define UNICAM_DLFO		BIT(28)
> +#define UNICAM_DLSTE		BIT(29)
> +
> +#define UNICAM_DAT_MASK_ALL	(UNICAM_DLSTE | UNICAM_DLFO)
> +
> +/* UNICAM_DLT Register */
> +#define UNICAM_DLT1_MASK	GENMASK(7, 0)
> +#define UNICAM_DLT2_MASK	GENMASK(15, 8)
> +#define UNICAM_DLT3_MASK	GENMASK(23, 16)
> +
> +/* UNICAM_ICTL Register */
> +#define UNICAM_FSIE		BIT(0)
> +#define UNICAM_FEIE		BIT(1)
> +#define UNICAM_IBOB		BIT(2)
> +#define UNICAM_FCM		BIT(3)
> +#define UNICAM_TFC		BIT(4)
> +#define UNICAM_LIP_MASK		GENMASK(6, 5)
> +#define UNICAM_LCIE_MASK	GENMASK(28, 16)
> +
> +/* UNICAM_IDI0/1 Register */
> +#define UNICAM_ID0_MASK		GENMASK(7, 0)
> +#define UNICAM_ID1_MASK		GENMASK(15, 8)
> +#define UNICAM_ID2_MASK		GENMASK(23, 16)
> +#define UNICAM_ID3_MASK		GENMASK(31, 24)
> +
> +/* UNICAM_ISTA Register */
> +#define UNICAM_FSI		BIT(0)
> +#define UNICAM_FEI		BIT(1)
> +#define UNICAM_LCI		BIT(2)
> +
> +#define UNICAM_ISTA_MASK_ALL	(UNICAM_FSI | UNICAM_FEI | UNICAM_LCI)
> +
> +/* UNICAM_IPIPE Register */
> +#define UNICAM_PUM_MASK		GENMASK(2, 0)
> +/* Unpacking modes */
> +#define UNICAM_PUM_NONE		0
> +#define UNICAM_PUM_UNPACK6	1
> +#define UNICAM_PUM_UNPACK7	2
> +#define UNICAM_PUM_UNPACK8	3
> +#define UNICAM_PUM_UNPACK10	4
> +#define UNICAM_PUM_UNPACK12	5
> +#define UNICAM_PUM_UNPACK14	6
> +#define UNICAM_PUM_UNPACK16	7
> +#define UNICAM_DDM_MASK		GENMASK(6, 3)
> +#define UNICAM_PPM_MASK		GENMASK(9, 7)
> +/* Packing modes */
> +#define UNICAM_PPM_NONE		0
> +#define UNICAM_PPM_PACK8	1
> +#define UNICAM_PPM_PACK10	2
> +#define UNICAM_PPM_PACK12	3
> +#define UNICAM_PPM_PACK14	4
> +#define UNICAM_PPM_PACK16	5
> +#define UNICAM_DEM_MASK		GENMASK(11, 10)
> +#define UNICAM_DEBL_MASK	GENMASK(14, 12)
> +#define UNICAM_ICM_MASK		GENMASK(16, 15)
> +#define UNICAM_IDM_MASK		GENMASK(17, 17)
> +
> +/* UNICAM_ICC Register */
> +#define UNICAM_ICFL_MASK	GENMASK(4, 0)
> +#define UNICAM_ICFH_MASK	GENMASK(9, 5)
> +#define UNICAM_ICST_MASK	GENMASK(12, 10)
> +#define UNICAM_ICLT_MASK	GENMASK(15, 13)
> +#define UNICAM_ICLL_MASK	GENMASK(31, 16)
> +
> +/* UNICAM_DCS Register */
> +#define UNICAM_DIE		BIT(0)
> +#define UNICAM_DIM		BIT(1)
> +#define UNICAM_DBOB		BIT(3)
> +#define UNICAM_FDE		BIT(4)
> +#define UNICAM_LDP		BIT(5)
> +#define UNICAM_EDL_MASK		GENMASK(15, 8)
> +
> +/* UNICAM_DBCTL Register */
> +#define UNICAM_DBEN		BIT(0)
> +#define UNICAM_BUF0_IE		BIT(1)
> +#define UNICAM_BUF1_IE		BIT(2)
> +
> +/* UNICAM_CMP[0,1] register */
> +#define UNICAM_PCE		BIT(31)
> +#define UNICAM_GI		BIT(9)
> +#define UNICAM_CPH		BIT(8)
> +#define UNICAM_PCVC_MASK	GENMASK(7, 6)
> +#define UNICAM_PCDT_MASK	GENMASK(5, 0)
> +
> +/* UNICAM_MISC register */
> +#define UNICAM_FL0		BIT(6)
> +#define UNICAM_FL1		BIT(9)
> +
> +#endif
> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> new file mode 100644
> index 000000000000..716c89b8a217
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> @@ -0,0 +1,2607 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * BCM283x / BCM271x Unicam Capture Driver
> + *
> + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> + *
> + * Dave Stevenson <[e-mail]>
> + *
> + * Based on TI am437x driver by
> + *   Benoit Parrot <[e-mail]>
> + *   Lad, Prabhakar <[e-mail]>
> + *
> + * and TI CAL camera interface driver by
> + *    Benoit Parrot <[e-mail]>
> + *
> + *
> + * There are two camera drivers in the kernel for BCM283x - this one and
> + * bcm2835-camera (currently in staging).
> + *
> + * This driver directly controls the Unicam peripheral - there is no
> + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> + * and writes it into SDRAM. The only potential processing options are to
> + * repack Bayer data into an alternate format, and applying windowing. The
> + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> + * where the relevant formats are defined, and will automatically configure the
> + * repacking as required. Support for windowing may be added later.

Does this last paragraph applies ? I see all the supported packed raw
format having an 'unpacked_fourcc' associated (all but the 8 bit ones
ofc)

> + *
> + * It should be possible to connect this driver to any sensor with a suitable
> + * output interface and V4L2 subdevice driver.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +#include <linux/videodev2.h>
> +
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-dev.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-mc.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "bcm2835-unicam-regs.h"
> +
> +#define UNICAM_MODULE_NAME		"unicam"
> +
> +/*
> + * Unicam must request a minimum of 250Mhz from the VPU clock.
> + * Otherwise the input FIFOs overrun and cause image corruption.
> + */
> +#define UNICAM_MIN_VPU_CLOCK_RATE	(250 * 1000 * 1000)

Shouldn't this be set in DT ?

> +
> +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> +#define UNICAM_DMA_BPL_ALIGNMENT	16
> +
> +/*
> + * The image stride is stored in a 16 bit register, and needs to be aligned to
> + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> + * constraint on its input, set the image stride alignment to 32 bytes here as
> + * well to avoid incompatible configurations.
> + */
> +#define UNICAM_IMAGE_BPL_ALIGNMENT	32
> +#define UNICAM_IMAGE_MAX_BPL		((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
> +
> +/*
> + * Max width is therefore determined by the max stride divided by the number of
> + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> + * so adopt a square image for want of anything better.
> + */
> +#define UNICAM_IMAGE_MIN_WIDTH		16
> +#define UNICAM_IMAGE_MIN_HEIGHT		16
> +#define UNICAM_IMAGE_MAX_WIDTH		(UNICAM_IMAGE_MAX_BPL / 4)
> +#define UNICAM_IMAGE_MAX_HEIGHT		UNICAM_IMAGE_MAX_WIDTH
> +
> +/*
> + * There's no intrinsic limits on the width and height for embedded dat. Use
> + * the same maximum values as for the image, to avoid overflows in the image
> + * size computation.
> + */
> +#define UNICAM_META_MIN_WIDTH		1
> +#define UNICAM_META_MIN_HEIGHT		1
> +#define UNICAM_META_MAX_WIDTH		UNICAM_IMAGE_MAX_WIDTH
> +#define UNICAM_META_MAX_HEIGHT		UNICAM_IMAGE_MAX_HEIGHT
> +
> +/*
> + * Size of the dummy buffer. Can be any size really, but the DMA
> + * allocation works in units of page sizes.
> + */
> +#define UNICAM_DUMMY_BUF_SIZE		PAGE_SIZE
> +
> +#define UNICAM_SD_PAD_SINK		0
> +#define UNICAM_SD_PAD_SOURCE_IMAGE	1
> +#define UNICAM_SD_PAD_SOURCE_METADATA	2
> +#define UNICAM_SD_NUM_PADS		(1 + UNICAM_SD_PAD_SOURCE_METADATA)

How about an enum then ?

> +
> +enum unicam_node_type {
> +	UNICAM_IMAGE_NODE,
> +	UNICAM_METADATA_NODE,
> +	UNICAM_MAX_NODES
> +};
> +
> +/*
> + * struct unicam_format_info - Unicam media bus format information
> + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> + * out to 16bpp. 0 if n/a.
> + * @code: V4L2 media bus format code.
> + * @depth: Bits per pixel as delivered from the source.
> + * @csi_dt: CSI data type.
> + * @metadata_fmt: This format only applies to the metadata pad.
> + */
> +struct unicam_format_info {
> +	u32	fourcc;
> +	u32	unpacked_fourcc;
> +	u32	code;
> +	u8	depth;
> +	u8	csi_dt;
> +	bool	metadata_fmt;
> +};
> +
> +struct unicam_buffer {
> +	struct vb2_v4l2_buffer vb;
> +	struct list_head list;
> +	dma_addr_t dma_addr;
> +	unsigned int size;
> +};
> +
> +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> +{
> +	return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> +}
> +
> +struct unicam_node {
> +	bool registered;
> +	bool streaming;
> +	unsigned int id;
> +
> +	/* Pointer to the current v4l2_buffer */
> +	struct unicam_buffer *cur_frm;
> +	/* Pointer to the next v4l2_buffer */
> +	struct unicam_buffer *next_frm;
> +	/* video capture */
> +	const struct unicam_format_info *fmtinfo;
> +	/* Used to store current pixel format */
> +	struct v4l2_format fmt;
> +	/* Buffer queue used in video-buf */
> +	struct vb2_queue buffer_queue;
> +	/* Queue of filled frames */
> +	struct list_head dma_queue;
> +	/* IRQ lock for DMA queue */
> +	spinlock_t dma_queue_lock;
> +	/* lock used to access this structure */
> +	struct mutex lock;
> +	/* Identifies video device for this channel */
> +	struct video_device video_dev;
> +	/* Pointer to the parent handle */
> +	struct unicam_device *dev;
> +	struct media_pad pad;
> +	/*
> +	 * Dummy buffer intended to be used by unicam
> +	 * if we have no other queued buffers to swap to.
> +	 */
> +	struct unicam_buffer dummy_buf;
> +	void *dummy_buf_cpu_addr;
> +};
> +
> +struct unicam_device {
> +	struct kref kref;
> +
> +	/* peripheral base address */
> +	void __iomem *base;
> +	/* clock gating base address */
> +	void __iomem *clk_gate_base;

Is the clock gating part of unicam or should this be expressed as a
clock provide and be referenced in DT through a phandle ?

> +	/* lp clock handle */
> +	struct clk *clock;
> +	/* vpu clock handle */
> +	struct clk *vpu_clock;
> +	/* V4l2 device */
> +	struct v4l2_device v4l2_dev;
> +	struct media_device mdev;
> +
> +	/* parent device */
> +	struct device *dev;
> +	/* subdevice async Notifier */

s/Notifier/notifier

> +	struct v4l2_async_notifier notifier;
> +	unsigned int sequence;
> +
> +	/* Sensor node */
> +	struct {
> +		struct v4l2_subdev *subdev;
> +		struct media_pad *pad;
> +	} sensor;
> +
> +	/* Internal subdev */
> +	struct {
> +		struct v4l2_subdev sd;
> +		struct media_pad pads[UNICAM_SD_NUM_PADS];
> +		bool streaming;
> +	} subdev;
> +
> +	enum v4l2_mbus_type bus_type;
> +	/*
> +	 * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> +	 * bus.mipi_csi1.strobe for CCP2.
> +	 */
> +	unsigned int bus_flags;
> +	unsigned int max_data_lanes;
> +	unsigned int active_data_lanes;
> +
> +	struct media_pipeline pipe;
> +
> +	struct unicam_node node[UNICAM_MAX_NODES];
> +};
> +
> +static inline struct unicam_device *
> +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> +{
> +	return container_of(notifier, struct unicam_device, notifier);
> +}
> +
> +static inline struct unicam_device *

I thought using inline is disouraged as the compiler knows what to do

> +sd_to_unicam_device(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct unicam_device, subdev.sd);

You can also use container_of_const() if you need it

> +}
> +
> +static void unicam_release(struct kref *kref)
> +{
> +	struct unicam_device *unicam =
> +		container_of(kref, struct unicam_device, kref);
> +
> +	if (unicam->mdev.dev)
> +		media_device_cleanup(&unicam->mdev);
> +
> +	kfree(unicam);
> +}
> +
> +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> +{
> +	kref_get(&unicam->kref);
> +	return unicam;
> +}
> +
> +static void unicam_put(struct unicam_device *unicam)
> +{
> +	kref_put(&unicam->kref, unicam_release);
> +}
> +

Does this handle a bit more gracefully the pesky lifetime management
issue in v4l2 ?

> +/* -----------------------------------------------------------------------------
> + * Misc helper functions
> + */
> +
> +static inline bool unicam_sd_pad_is_source(u32 pad)
> +{
> +	/* Camera RX has 1 sink pad, and N source pads */
> +	return pad != UNICAM_SD_PAD_SINK;
> +}
> +
> +static inline bool is_metadata_node(struct unicam_node *node)
> +{
> +	return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> +}
> +
> +static inline bool is_image_node(struct unicam_node *node)
> +{
> +	return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Format data table and helper functions
> + */
> +
> +static const struct v4l2_mbus_framefmt unicam_default_image_format = {
> +	.width = 640,
> +	.height = 480,
> +	.code = MEDIA_BUS_FMT_UYVY8_1X16,
> +	.field = V4L2_FIELD_NONE,
> +	.colorspace = V4L2_COLORSPACE_SRGB,
> +	.ycbcr_enc = V4L2_YCBCR_ENC_601,
> +	.quantization = V4L2_QUANTIZATION_LIM_RANGE,
> +	.xfer_func = V4L2_XFER_FUNC_SRGB,
> +	.flags = 0,
> +};
> +
> +static const struct v4l2_mbus_framefmt unicam_default_meta_format = {
> +	.width = 640,
> +	.height = 2,
> +	.code = MEDIA_BUS_FMT_META_8,
> +	.field = V4L2_FIELD_NONE,
> +};
> +
> +static const struct unicam_format_info unicam_image_formats[] = {
> +	/* YUV Formats */
> +	{
> +		.fourcc		= V4L2_PIX_FMT_YUYV,
> +		.code		= MEDIA_BUS_FMT_YUYV8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_UYVY,
> +		.code		= MEDIA_BUS_FMT_UYVY8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_YVYU,
> +		.code		= MEDIA_BUS_FMT_YVYU8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_VYUY,
> +		.code		= MEDIA_BUS_FMT_VYUY8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +	/* RGB Formats */
> +		.fourcc		= V4L2_PIX_FMT_RGB565, /* gggbbbbb rrrrrggg */
> +		.code		= MEDIA_BUS_FMT_RGB565_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x22,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_RGB24, /* rgb */
> +		.code		= MEDIA_BUS_FMT_RGB888_1X24,
> +		.depth		= 24,
> +		.csi_dt		= 0x24,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_BGR24, /* bgr */
> +		.code		= MEDIA_BUS_FMT_BGR888_1X24,
> +		.depth		= 24,
> +		.csi_dt		= 0x24,
> +	}, {
> +	/* Bayer Formats */
> +		.fourcc		= V4L2_PIX_FMT_SBGGR8,
> +		.code		= MEDIA_BUS_FMT_SBGGR8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG8,
> +		.code		= MEDIA_BUS_FMT_SGBRG8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG8,
> +		.code		= MEDIA_BUS_FMT_SGRBG8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB8,
> +		.code		= MEDIA_BUS_FMT_SRGGB8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SBGGR10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR10,
> +		.code		= MEDIA_BUS_FMT_SBGGR10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG10,
> +		.code		= MEDIA_BUS_FMT_SGBRG10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG10,
> +		.code		= MEDIA_BUS_FMT_SGRBG10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB10,
> +		.code		= MEDIA_BUS_FMT_SRGGB10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SBGGR12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR12,
> +		.code		= MEDIA_BUS_FMT_SBGGR12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG12,
> +		.code		= MEDIA_BUS_FMT_SGBRG12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG12,
> +		.code		= MEDIA_BUS_FMT_SGRBG12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB12,
> +		.code		= MEDIA_BUS_FMT_SRGGB12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SBGGR14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR14,
> +		.code		= MEDIA_BUS_FMT_SBGGR14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG14,
> +		.code		= MEDIA_BUS_FMT_SGBRG14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG14,
> +		.code		= MEDIA_BUS_FMT_SGRBG14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB14,
> +		.code		= MEDIA_BUS_FMT_SRGGB14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +	/* 16 bit Bayer formats could be supported. */
> +
> +	/* Greyscale formats */
> +		.fourcc		= V4L2_PIX_FMT_GREY,
> +		.code		= MEDIA_BUS_FMT_Y8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_Y10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_Y10,
> +		.code		= MEDIA_BUS_FMT_Y10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_Y12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_Y12,
> +		.code		= MEDIA_BUS_FMT_Y12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_Y14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_Y14,
> +		.code		= MEDIA_BUS_FMT_Y14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	},
> +};
> +
> +static const struct unicam_format_info unicam_meta_formats[] = {
> +	{
> +		.fourcc		= V4L2_META_FMT_GENERIC_8,
> +		.code		= MEDIA_BUS_FMT_META_8,
> +		.depth		= 8,
> +		.metadata_fmt	= true,
> +	}, {
> +		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_10,
> +		.code		= MEDIA_BUS_FMT_META_10,
> +		.depth		= 10,
> +		.metadata_fmt	= true,
> +	}, {
> +		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_12,
> +		.code		= MEDIA_BUS_FMT_META_12,
> +		.depth		= 12,
> +		.metadata_fmt	= true,
> +	}, {
> +		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_14,
> +		.code		= MEDIA_BUS_FMT_META_14,
> +		.depth		= 14,
> +		.metadata_fmt	= true,
> +	},
> +};
> +
> +/* Format setup functions */
> +static const struct unicam_format_info *
> +unicam_find_format_by_code(u32 code, u32 pad)
> +{
> +	const struct unicam_format_info *formats;
> +	unsigned int num_formats;
> +	unsigned int i;
> +
> +	if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +		formats = unicam_image_formats;
> +		num_formats = ARRAY_SIZE(unicam_image_formats);
> +	} else {
> +		formats = unicam_meta_formats;
> +		num_formats = ARRAY_SIZE(unicam_meta_formats);
> +	}
> +
> +	for (i = 0; i < num_formats; i++) {
> +		if (formats[i].code == code)
> +			return &formats[i];
> +	}
> +
> +	return NULL;
> +}
> +
> +static const struct unicam_format_info *
> +unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
> +{
> +	const struct unicam_format_info *formats;
> +	unsigned int num_formats;
> +	unsigned int i;
> +
> +	if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +		formats = unicam_image_formats;
> +		num_formats = ARRAY_SIZE(unicam_image_formats);
> +	} else {
> +		formats = unicam_meta_formats;
> +		num_formats = ARRAY_SIZE(unicam_meta_formats);
> +	}
> +
> +	for (i = 0; i < num_formats; ++i) {
> +		if (formats[i].fourcc == fourcc)
> +			return &formats[i];
> +	}
> +
> +	return NULL;
> +}
> +
> +static void unicam_calc_image_size_bpl(struct unicam_device *unicam,
> +				       const struct unicam_format_info *fmtinfo,
> +				       struct v4l2_pix_format *pix)
> +{
> +	u32 min_bpl;
> +
> +	v4l_bound_align_image(&pix->width, UNICAM_IMAGE_MIN_WIDTH,
> +			      UNICAM_IMAGE_MAX_WIDTH, 2,
> +			      &pix->height, UNICAM_IMAGE_MIN_HEIGHT,
> +			      UNICAM_IMAGE_MAX_HEIGHT, 0, 0);
> +
> +	/* Unpacking always goes to 16bpp */
> +	if (pix->pixelformat == fmtinfo->unpacked_fourcc)
> +		min_bpl = pix->width * 2;
> +	else
> +		min_bpl = pix->width * fmtinfo->depth / 8;
> +	min_bpl = ALIGN(min_bpl, UNICAM_IMAGE_BPL_ALIGNMENT);
> +
> +	pix->bytesperline = ALIGN(pix->bytesperline, UNICAM_IMAGE_BPL_ALIGNMENT);
> +	pix->bytesperline = clamp_t(unsigned int, pix->bytesperline, min_bpl,
> +				    UNICAM_IMAGE_MAX_BPL);
> +
> +	pix->sizeimage = pix->height * pix->bytesperline;
> +}
> +
> +static void unicam_calc_meta_size_bpl(struct unicam_device *unicam,
> +				      const struct unicam_format_info *fmtinfo,
> +				      struct v4l2_meta_format *meta)
> +{
> +	v4l_bound_align_image(&meta->width, UNICAM_META_MIN_WIDTH,
> +			      UNICAM_META_MAX_WIDTH, 0,
> +			      &meta->height, UNICAM_META_MIN_HEIGHT,
> +			      UNICAM_META_MAX_HEIGHT, 0, 0);
> +
> +	meta->bytesperline = ALIGN(meta->width * fmtinfo->depth / 8,
> +				   UNICAM_DMA_BPL_ALIGNMENT);
> +	meta->buffersize = meta->height * meta->bytesperline;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Hardware handling
> + */
> +

As this has been used for years in BSP driver, I won't go in detail in
the HW handling functions

> +static inline void unicam_clk_write(struct unicam_device *unicam, u32 val)
> +{
> +	/* Pass the CM_PASSWORD along with the value. */
> +	writel(val | 0x5a000000, unicam->clk_gate_base);
> +}
> +
> +static inline u32 unicam_reg_read(struct unicam_device *unicam, u32 offset)
> +{
> +	return readl(unicam->base + offset);
> +}
> +
> +static inline void unicam_reg_write(struct unicam_device *unicam, u32 offset, u32 val)
> +{
> +	writel(val, unicam->base + offset);
> +}
> +
> +static inline int unicam_get_field(u32 value, u32 mask)
> +{
> +	return (value & mask) >> __ffs(mask);
> +}
> +
> +static inline void unicam_set_field(u32 *valp, u32 field, u32 mask)
> +{
> +	u32 val = *valp;
> +
> +	val &= ~mask;
> +	val |= (field << __ffs(mask)) & mask;
> +	*valp = val;
> +}
> +
> +static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offset,
> +					  u32 field, u32 mask)
> +{
> +	u32 val = unicam_reg_read(unicam, offset);
> +
> +	unicam_set_field(&val, field, mask);
> +	unicam_reg_write(unicam, offset, val);
> +}
> +
> +static void unicam_wr_dma_addr(struct unicam_node *node,
> +			       struct unicam_buffer *buf)
> +{
> +	dma_addr_t endaddr = buf->dma_addr + buf->size;
> +
> +	if (node->id == UNICAM_IMAGE_NODE) {
> +		unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
> +		unicam_reg_write(node->dev, UNICAM_IBEA0, endaddr);
> +	} else {
> +		unicam_reg_write(node->dev, UNICAM_DBSA0, buf->dma_addr);
> +		unicam_reg_write(node->dev, UNICAM_DBEA0, endaddr);
> +	}
> +}
> +
> +static unsigned int unicam_get_lines_done(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +	unsigned int stride = node->fmt.fmt.pix.bytesperline;
> +	struct unicam_buffer *frm = node->cur_frm;
> +	dma_addr_t cur_addr;
> +
> +	if (!frm)
> +		return 0;
> +
> +	cur_addr = unicam_reg_read(unicam, UNICAM_IBWP);
> +	return (unsigned int)(cur_addr - frm->dma_addr) / stride;
> +}
> +
> +static void unicam_schedule_next_buffer(struct unicam_node *node)
> +{
> +	struct unicam_buffer *buf;
> +
> +	buf = list_first_entry(&node->dma_queue, struct unicam_buffer, list);
> +	node->next_frm = buf;
> +	list_del(&buf->list);
> +
> +	unicam_wr_dma_addr(node, buf);
> +}
> +
> +static void unicam_schedule_dummy_buffer(struct unicam_node *node)
> +{
> +	int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
> +
> +	dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
> +
> +	unicam_wr_dma_addr(node, &node->dummy_buf);
> +
> +	node->next_frm = NULL;
> +}
> +
> +static void unicam_process_buffer_complete(struct unicam_node *node,
> +					   unsigned int sequence)
> +{
> +	node->cur_frm->vb.field = node->fmt.fmt.pix.field;
> +	node->cur_frm->vb.sequence = sequence;
> +
> +	vb2_buffer_done(&node->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
> +}
> +
> +static void unicam_queue_event_sof(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +
> +	struct v4l2_event event = {
> +		.type = V4L2_EVENT_FRAME_SYNC,
> +		.u.frame_sync.frame_sequence = unicam->sequence,
> +	};
> +
> +	v4l2_event_queue(&node->video_dev, &event);
> +}
> +
> +static irqreturn_t unicam_isr(int irq, void *dev)
> +{
> +	struct unicam_device *unicam = dev;
> +	unsigned int lines_done = unicam_get_lines_done(dev);
> +	unsigned int sequence = unicam->sequence;
> +	unsigned int i;
> +	u32 ista, sta;
> +	bool fe;
> +	u64 ts;
> +
> +	sta = unicam_reg_read(unicam, UNICAM_STA);
> +	/* Write value back to clear the interrupts */
> +	unicam_reg_write(unicam, UNICAM_STA, sta);
> +
> +	ista = unicam_reg_read(unicam, UNICAM_ISTA);
> +	/* Write value back to clear the interrupts */
> +	unicam_reg_write(unicam, UNICAM_ISTA, ista);
> +
> +	dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> +		ista, sta, sequence, lines_done);
> +
> +	if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> +		return IRQ_HANDLED;
> +
> +	/*
> +	 * Look for either the Frame End interrupt or the Packet Capture status
> +	 * to signal a frame end.
> +	 */
> +	fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> +
> +	/*
> +	 * We must run the frame end handler first. If we have a valid next_frm
> +	 * and we get a simultaneout FE + FS interrupt, running the FS handler
> +	 * first would null out the next_frm ptr and we would have lost the
> +	 * buffer forever.
> +	 */
> +	if (fe) {
> +		/*
> +		 * Ensure we have swapped buffers already as we can't
> +		 * stop the peripheral. If no buffer is available, use a
> +		 * dummy buffer to dump out frames until we get a new buffer
> +		 * to use.
> +		 */
> +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +			if (!unicam->node[i].streaming)
> +				continue;
> +
> +			/*
> +			 * If cur_frm == next_frm, it means we have not had
> +			 * a chance to swap buffers, likely due to having
> +			 * multiple interrupts occurring simultaneously (like FE
> +			 * + FS + LS). In this case, we cannot signal the buffer
> +			 * as complete, as the HW will reuse that buffer.
> +			 */
> +			if (unicam->node[i].cur_frm &&
> +			    unicam->node[i].cur_frm != unicam->node[i].next_frm)
> +				unicam_process_buffer_complete(&unicam->node[i],
> +							       sequence);
> +			unicam->node[i].cur_frm = unicam->node[i].next_frm;
> +		}
> +		unicam->sequence++;
> +	}
> +
> +	if (ista & UNICAM_FSI) {
> +		/*
> +		 * Timestamp is to be when the first data byte was captured,
> +		 * aka frame start.
> +		 */
> +		ts = ktime_get_ns();
> +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +			if (!unicam->node[i].streaming)
> +				continue;
> +
> +			if (unicam->node[i].cur_frm)
> +				unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> +								ts;
> +			else
> +				dev_dbg(unicam->v4l2_dev.dev,
> +					"ISR: [%d] Dropping frame, buffer not available at FS\n",
> +					i);
> +			/*
> +			 * Set the next frame output to go to a dummy frame
> +			 * if we have not managed to obtain another frame
> +			 * from the queue.
> +			 */
> +			unicam_schedule_dummy_buffer(&unicam->node[i]);
> +		}
> +
> +		unicam_queue_event_sof(unicam);
> +	}
> +
> +	/*
> +	 * Cannot swap buffer at frame end, there may be a race condition
> +	 * where the HW does not actually swap it if the new frame has
> +	 * already started.
> +	 */
> +	if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +			if (!unicam->node[i].streaming)
> +				continue;
> +
> +			spin_lock(&unicam->node[i].dma_queue_lock);
> +			if (!list_empty(&unicam->node[i].dma_queue) &&
> +			    !unicam->node[i].next_frm)
> +				unicam_schedule_next_buffer(&unicam->node[i]);
> +			spin_unlock(&unicam->node[i].dma_queue_lock);
> +		}
> +	}
> +
> +	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> +		/* Switch out of trigger mode if selected */
> +		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> +		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> +	}
> +	return IRQ_HANDLED;
> +}
> +
> +static void unicam_set_packing_config(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +	u32 pack, unpack;
> +	u32 val;
> +
> +	if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> +		unpack = UNICAM_PUM_NONE;
> +		pack = UNICAM_PPM_NONE;
> +	} else {
> +		switch (node->fmtinfo->depth) {
> +		case 8:
> +			unpack = UNICAM_PUM_UNPACK8;
> +			break;
> +		case 10:
> +			unpack = UNICAM_PUM_UNPACK10;
> +			break;
> +		case 12:
> +			unpack = UNICAM_PUM_UNPACK12;
> +			break;
> +		case 14:
> +			unpack = UNICAM_PUM_UNPACK14;
> +			break;
> +		case 16:
> +			unpack = UNICAM_PUM_UNPACK16;
> +			break;
> +		default:
> +			unpack = UNICAM_PUM_NONE;
> +			break;
> +		}
> +
> +		/* Repacking is always to 16bpp */
> +		pack = UNICAM_PPM_PACK16;
> +	}
> +
> +	val = 0;
> +	unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> +	unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> +	unicam_reg_write(unicam, UNICAM_IPIPE, val);
> +}
> +
> +static void unicam_cfg_image_id(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		/* CSI2 mode, hardcode VC 0 for now. */
> +		unicam_reg_write(unicam, UNICAM_IDI0,
> +				 (0 << 6) | node->fmtinfo->csi_dt);
> +	} else {
> +		/* CCP2 mode */
> +		unicam_reg_write(unicam, UNICAM_IDI0,
> +				 0x80 | node->fmtinfo->csi_dt);
> +	}
> +}
> +
> +static void unicam_enable_ed(struct unicam_device *unicam)
> +{
> +	u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> +
> +	unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> +	/* Do not wrap at the end of the embedded data buffer */
> +	unicam_set_field(&val, 0, UNICAM_DBOB);
> +
> +	unicam_reg_write(unicam, UNICAM_DCS, val);
> +}
> +
> +static void unicam_start_rx(struct unicam_device *unicam,
> +			    struct unicam_buffer *buf)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +	int line_int_freq = node->fmt.fmt.pix.height >> 2;
> +	unsigned int i;
> +	u32 val;
> +
> +	if (line_int_freq < 128)
> +		line_int_freq = 128;
> +
> +	/* Enable lane clocks */
> +	val = 1;
> +	for (i = 0; i < unicam->active_data_lanes; i++)
> +		val = val << 2 | 1;
> +	unicam_clk_write(unicam, val);
> +
> +	/* Basic init */
> +	unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> +
> +	/* Enable analogue control, and leave in reset. */
> +	val = UNICAM_AR;
> +	unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> +	unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> +	unicam_reg_write(unicam, UNICAM_ANA, val);
> +	usleep_range(1000, 2000);
> +
> +	/* Come out of reset */
> +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> +
> +	/* Peripheral reset */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> +
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> +
> +	/* Enable Rx control. */
> +	val = unicam_reg_read(unicam, UNICAM_CTRL);
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> +		unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> +	} else {
> +		unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> +		unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> +	}
> +	/* Packet framer timeout */
> +	unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> +	unicam_set_field(&val, 128, UNICAM_OET_MASK);
> +	unicam_reg_write(unicam, UNICAM_CTRL, val);
> +
> +	unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> +	unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> +
> +	/* AXI bus access QoS setup */
> +	val = unicam_reg_read(unicam, UNICAM_PRI);
> +	unicam_set_field(&val, 0, UNICAM_BL_MASK);
> +	unicam_set_field(&val, 0, UNICAM_BS_MASK);
> +	unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> +	unicam_set_field(&val, 8, UNICAM_NP_MASK);
> +	unicam_set_field(&val, 2, UNICAM_PT_MASK);
> +	unicam_set_field(&val, 1, UNICAM_PE);
> +	unicam_reg_write(unicam, UNICAM_PRI, val);
> +
> +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> +
> +	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
> +	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> +	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> +	unicam_reg_write(unicam, UNICAM_ICTL, val);
> +	unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> +	unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> +
> +	/* tclk_term_en */
> +	unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> +	/* tclk_settle */
> +	unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> +	/* td_term_en */
> +	unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> +	/* ths_settle */
> +	unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> +	/* trx_enable */
> +	unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> +
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> +
> +	/* Packet compare setup - required to avoid missing frame ends */
> +	val = 0;
> +	unicam_set_field(&val, 1, UNICAM_PCE);
> +	unicam_set_field(&val, 1, UNICAM_GI);
> +	unicam_set_field(&val, 1, UNICAM_CPH);
> +	unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> +	unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> +	unicam_reg_write(unicam, UNICAM_CMP0, val);
> +
> +	/* Enable clock lane and set up terminations */
> +	val = 0;
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		/* CSI2 */
> +		unicam_set_field(&val, 1, UNICAM_CLE);
> +		unicam_set_field(&val, 1, UNICAM_CLLPE);
> +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> +			unicam_set_field(&val, 1, UNICAM_CLTRE);
> +			unicam_set_field(&val, 1, UNICAM_CLHSE);
> +		}
> +	} else {
> +		/* CCP2 */
> +		unicam_set_field(&val, 1, UNICAM_CLE);
> +		unicam_set_field(&val, 1, UNICAM_CLHSE);
> +		unicam_set_field(&val, 1, UNICAM_CLTRE);
> +	}
> +	unicam_reg_write(unicam, UNICAM_CLK, val);
> +
> +	/*
> +	 * Enable required data lanes with appropriate terminations.
> +	 * The same value needs to be written to UNICAM_DATn registers for
> +	 * the active lanes, and 0 for inactive ones.
> +	 */
> +	val = 0;
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		/* CSI2 */
> +		unicam_set_field(&val, 1, UNICAM_DLE);
> +		unicam_set_field(&val, 1, UNICAM_DLLPE);
> +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> +			unicam_set_field(&val, 1, UNICAM_DLTRE);
> +			unicam_set_field(&val, 1, UNICAM_DLHSE);
> +		}
> +	} else {
> +		/* CCP2 */
> +		unicam_set_field(&val, 1, UNICAM_DLE);
> +		unicam_set_field(&val, 1, UNICAM_DLHSE);
> +		unicam_set_field(&val, 1, UNICAM_DLTRE);
> +	}
> +	unicam_reg_write(unicam, UNICAM_DAT0, val);
> +
> +	if (unicam->active_data_lanes == 1)
> +		val = 0;
> +	unicam_reg_write(unicam, UNICAM_DAT1, val);
> +
> +	if (unicam->max_data_lanes > 2) {
> +		/*
> +		 * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> +		 * instance supports more than 2 data lanes.
> +		 */
> +		if (unicam->active_data_lanes == 2)
> +			val = 0;
> +		unicam_reg_write(unicam, UNICAM_DAT2, val);
> +
> +		if (unicam->active_data_lanes == 3)
> +			val = 0;
> +		unicam_reg_write(unicam, UNICAM_DAT3, val);
> +	}
> +
> +	unicam_reg_write(unicam, UNICAM_IBLS,
> +			 node->fmt.fmt.pix.bytesperline);
> +	unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> +	unicam_set_packing_config(unicam);
> +	unicam_cfg_image_id(unicam);
> +
> +	val = unicam_reg_read(unicam, UNICAM_MISC);
> +	unicam_set_field(&val, 1, UNICAM_FL0);
> +	unicam_set_field(&val, 1, UNICAM_FL1);
> +	unicam_reg_write(unicam, UNICAM_MISC, val);
> +
> +	/* Enable peripheral */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> +
> +	/* Load image pointers */
> +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> +
> +	/*
> +	 * Enable trigger only for the first frame to
> +	 * sync correctly to the FS from the source.
> +	 */
> +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> +}
> +
> +static void unicam_start_metadata(struct unicam_device *unicam,
> +				  struct unicam_buffer *buf)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
> +
> +	unicam_enable_ed(unicam);
> +	unicam_wr_dma_addr(node, buf);
> +	unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
> +}
> +
> +static void unicam_disable(struct unicam_device *unicam)
> +{
> +	/* Analogue lane control disable */
> +	unicam_reg_write_field(unicam, UNICAM_ANA, 1, UNICAM_DDL);
> +
> +	/* Stop the output engine */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_SOE);
> +
> +	/* Disable the data lanes. */
> +	unicam_reg_write(unicam, UNICAM_DAT0, 0);
> +	unicam_reg_write(unicam, UNICAM_DAT1, 0);
> +
> +	if (unicam->max_data_lanes > 2) {
> +		unicam_reg_write(unicam, UNICAM_DAT2, 0);
> +		unicam_reg_write(unicam, UNICAM_DAT3, 0);
> +	}
> +
> +	/* Peripheral reset */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> +	usleep_range(50, 100);
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> +
> +	/* Disable peripheral */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> +
> +	/* Clear ED setup */
> +	unicam_reg_write(unicam, UNICAM_DCS, 0);
> +
> +	/* Disable all lane clocks */
> +	unicam_clk_write(unicam, 0);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * V4L2 subdev operations
> + */
> +
> +static int __unicam_subdev_set_routing(struct v4l2_subdev *sd,
> +				       struct v4l2_subdev_state *state,
> +				       struct v4l2_subdev_krouting *routing)
> +{
> +	struct v4l2_subdev_route *route;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_validate(sd, routing,
> +					   V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_subdev_set_routing(sd, state, routing);
> +	if (ret)
> +		return ret;
> +
> +	for_each_active_route(&state->routing, route) {
> +		const struct v4l2_mbus_framefmt *def_fmt;
> +		struct v4l2_mbus_framefmt *fmt;
> +
> +		if (route->source_pad == UNICAM_SD_PAD_SOURCE_IMAGE)
> +			def_fmt = &unicam_default_image_format;
> +		else
> +			def_fmt = &unicam_default_meta_format;
> +
> +		fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
> +						   route->sink_stream);
> +		*fmt = *def_fmt;
> +		fmt = v4l2_subdev_state_get_format(state, route->source_pad,
> +						   route->source_stream);
> +		*fmt = *def_fmt;
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_init_state(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state)
> +{
> +	struct v4l2_subdev_route routes[] = {
> +		{
> +			.sink_pad = UNICAM_SD_PAD_SINK,
> +			.sink_stream = 0,
> +			.source_pad = UNICAM_SD_PAD_SOURCE_IMAGE,
> +			.source_stream = 0,
> +			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
> +		},
> +	};
> +
> +	struct v4l2_subdev_krouting routing = {
> +		.len_routes = ARRAY_SIZE(routes),
> +		.num_routes = ARRAY_SIZE(routes),
> +		.routes = routes,
> +	};
> +
> +	/* Initialize routing to single route to the fist source pad. */
> +	return __unicam_subdev_set_routing(sd, state, &routing);
> +}
> +
> +static int unicam_subdev_enum_mbus_code(struct v4l2_subdev *sd,
> +					struct v4l2_subdev_state *state,
> +					struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	u32 pad, stream;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +						    code->pad, code->stream,
> +						    &pad, &stream);
> +	if (ret)
> +		return ret;
> +
> +	if (unicam_sd_pad_is_source(code->pad)) {
> +		/* No transcoding, source and sink codes must match. */
> +		const struct v4l2_mbus_framefmt *fmt;
> +
> +		fmt = v4l2_subdev_state_get_format(state, pad, stream);
> +		if (!fmt)
> +			return -EINVAL;
> +
> +		if (code->index > 0)
> +			return -EINVAL;
> +
> +		code->code = fmt->code;
> +	} else {
> +		const struct unicam_format_info *formats;
> +		unsigned int num_formats;
> +
> +		if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +			formats = unicam_image_formats;
> +			num_formats = ARRAY_SIZE(unicam_image_formats);
> +		} else {
> +			formats = unicam_meta_formats;
> +			num_formats = ARRAY_SIZE(unicam_meta_formats);
> +		}
> +
> +		if (code->index >= num_formats)
> +			return -EINVAL;
> +
> +		code->code = formats[code->index].code;
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_enum_frame_size(struct v4l2_subdev *sd,
> +					 struct v4l2_subdev_state *state,
> +					 struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	u32 pad, stream;
> +	int ret;
> +
> +	if (fse->index > 0)
> +		return -EINVAL;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, fse->pad,
> +						    fse->stream, &pad,
> +						    &stream);
> +	if (ret)
> +		return ret;
> +
> +	if (unicam_sd_pad_is_source(fse->pad)) {
> +		/* No transcoding, source and sink formats must match. */
> +		const struct v4l2_mbus_framefmt *fmt;
> +
> +		fmt = v4l2_subdev_state_get_format(state, pad, stream);
> +		if (!fmt)
> +			return -EINVAL;
> +
> +		if (fse->code != fmt->code)
> +			return -EINVAL;
> +
> +		fse->min_width = fmt->width;
> +		fse->max_width = fmt->width;
> +		fse->min_height = fmt->height;
> +		fse->max_height = fmt->height;
> +	} else {
> +		const struct unicam_format_info *fmtinfo;
> +
> +		fmtinfo = unicam_find_format_by_code(fse->code, pad);
> +		if (!fmtinfo)
> +			return -EINVAL;
> +
> +		if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +			fse->min_width = UNICAM_IMAGE_MIN_WIDTH;
> +			fse->max_width = UNICAM_IMAGE_MAX_WIDTH;
> +			fse->min_height = UNICAM_IMAGE_MIN_HEIGHT;
> +			fse->max_height = UNICAM_IMAGE_MAX_HEIGHT;
> +		} else {
> +			fse->min_width = UNICAM_META_MIN_WIDTH;
> +			fse->max_width = UNICAM_META_MAX_WIDTH;
> +			fse->min_height = UNICAM_META_MIN_HEIGHT;
> +			fse->max_height = UNICAM_META_MAX_HEIGHT;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_set_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +	struct v4l2_mbus_framefmt *sink_format, *source_format;
> +	const struct unicam_format_info *fmtinfo;
> +	u32 source_pad, source_stream;
> +	int ret;
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
> +	    unicam->subdev.streaming)
> +		return -EBUSY;
> +
> +	/* No transcoding, source and sink formats must match. */
> +	if (unicam_sd_pad_is_source(format->pad))
> +		return v4l2_subdev_get_fmt(sd, state, format);
> +
> +	/*
> +	 * Allowed formats for the stream on the sink pad depend on what source
> +	 * pad the stream is routed to. Find the corresponding source pad and
> +	 * use it to validate the media bus code.
> +	 */
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +						    format->pad, format->stream,
> +						    &source_pad, &source_stream);
> +	if (ret)
> +		return ret;
> +
> +	fmtinfo = unicam_find_format_by_code(format->format.code, source_pad);
> +	if (!fmtinfo) {
> +		fmtinfo = source_pad == UNICAM_SD_PAD_SOURCE_IMAGE
> +			? &unicam_image_formats[0] : &unicam_meta_formats[0];
> +		format->format.code = fmtinfo->code;
> +	}
> +
> +	if (source_pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +		format->format.width = clamp_t(unsigned int,
> +					       format->format.width,
> +					       UNICAM_IMAGE_MIN_WIDTH,
> +					       UNICAM_IMAGE_MAX_WIDTH);
> +		format->format.height = clamp_t(unsigned int,
> +						format->format.height,
> +						UNICAM_IMAGE_MIN_HEIGHT,
> +						UNICAM_IMAGE_MAX_HEIGHT);
> +		format->format.field = V4L2_FIELD_NONE;
> +	} else {
> +		format->format.width = clamp_t(unsigned int,
> +					       format->format.width,
> +					       UNICAM_META_MIN_WIDTH,
> +					       UNICAM_META_MAX_WIDTH);
> +		format->format.height = clamp_t(unsigned int,
> +						format->format.height,
> +						UNICAM_META_MIN_HEIGHT,
> +						UNICAM_META_MAX_HEIGHT);
> +		format->format.field = V4L2_FIELD_NONE;
> +
> +		/* Colorspace don't apply to metadata. */
> +		format->format.colorspace = 0;
> +		format->format.ycbcr_enc = 0;
> +		format->format.quantization = 0;
> +		format->format.xfer_func = 0;
> +	}
> +
> +	sink_format = v4l2_subdev_state_get_format(state, format->pad,
> +						   format->stream);
> +	source_format = v4l2_subdev_state_get_format(state, source_pad,
> +						     source_stream);
> +	*sink_format = format->format;
> +	*source_format = format->format;
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_set_routing(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *state,
> +				     enum v4l2_subdev_format_whence which,
> +				     struct v4l2_subdev_krouting *routing)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +
> +	if (which == V4L2_SUBDEV_FORMAT_ACTIVE && unicam->subdev.streaming)
> +		return -EBUSY;
> +
> +	return __unicam_subdev_set_routing(sd, state, routing);
> +}
> +
> +static int unicam_sd_enable_streams(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state, u32 pad,
> +				    u64 streams_mask)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +	u32 other_pad, other_stream;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> +						    &other_pad, &other_stream);
> +	if (ret)
> +		return ret;
> +
> +	unicam->sequence = 0;
> +
> +	ret = v4l2_subdev_enable_streams(unicam->sensor.subdev,
> +					 unicam->sensor.pad->index,
> +					 BIT(other_stream));
> +	if (ret) {
> +		dev_err(unicam->dev, "stream on failed in subdev\n");
> +		return ret;
> +	}
> +
> +	unicam->subdev.streaming = true;
> +
> +	return 0;
> +}
> +
> +static int unicam_sd_disable_streams(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *state, u32 pad,
> +				     u64 streams_mask)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +	u32 other_pad, other_stream;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> +						    &other_pad, &other_stream);
> +	if (ret)
> +		return ret;
> +
> +	v4l2_subdev_disable_streams(unicam->sensor.subdev,
> +				    unicam->sensor.pad->index,
> +				    BIT(other_stream));
> +
> +	unicam->subdev.streaming = false;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_pad_ops unicam_subdev_pad_ops = {
> +	.enum_mbus_code		= unicam_subdev_enum_mbus_code,
> +	.enum_frame_size	= unicam_subdev_enum_frame_size,
> +	.get_fmt		= v4l2_subdev_get_fmt,
> +	.set_fmt		= unicam_subdev_set_format,
> +	.set_routing		= unicam_subdev_set_routing,
> +	.enable_streams		= unicam_sd_enable_streams,
> +	.disable_streams	= unicam_sd_disable_streams,
> +};
> +
> +static const struct v4l2_subdev_ops unicam_subdev_ops = {
> +	.pad			= &unicam_subdev_pad_ops,
> +};
> +
> +static const struct v4l2_subdev_internal_ops unicam_subdev_internal_ops = {
> +	.init_state		= unicam_subdev_init_state,
> +};
> +
> +static const struct media_entity_operations unicam_subdev_media_ops = {
> +	.link_validate		= v4l2_subdev_link_validate,
> +	.has_pad_interdep	= v4l2_subdev_has_pad_interdep,
> +};
> +
> +static int unicam_subdev_init(struct unicam_device *unicam)
> +{
> +	struct v4l2_subdev *sd = &unicam->subdev.sd;
> +	int ret;
> +
> +	v4l2_subdev_init(sd, &unicam_subdev_ops);
> +	sd->internal_ops = &unicam_subdev_internal_ops;
> +	v4l2_set_subdevdata(sd, unicam);
> +
> +	sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> +	sd->entity.ops = &unicam_subdev_media_ops;
> +	sd->dev = unicam->dev;
> +	sd->owner = THIS_MODULE;
> +	sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
> +
> +	strscpy(sd->name, "unicam", sizeof(sd->name));
> +
> +	unicam->subdev.pads[UNICAM_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> +	unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_IMAGE].flags = MEDIA_PAD_FL_SOURCE;
> +	unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_METADATA].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(unicam->subdev.pads),
> +				     unicam->subdev.pads);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to initialize media entity: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	ret = v4l2_subdev_init_finalize(sd);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to initialize subdev: %d\n", ret);
> +		goto err_entity;
> +	}
> +
> +	ret = v4l2_device_register_subdev(&unicam->v4l2_dev, sd);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to register subdev: %d\n", ret);
> +		goto err_subdev;
> +	}
> +
> +	return 0;
> +
> +err_subdev:
> +	v4l2_subdev_cleanup(sd);
> +err_entity:
> +	media_entity_cleanup(&sd->entity);
> +	return ret;
> +}
> +
> +static void unicam_subdev_cleanup(struct unicam_device *unicam)
> +{
> +	v4l2_subdev_cleanup(&unicam->subdev.sd);
> +	media_entity_cleanup(&unicam->subdev.sd.entity);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Videobuf2 queue operations
> + */
> +
> +static int unicam_queue_setup(struct vb2_queue *vq,
> +			      unsigned int *nbuffers,
> +			      unsigned int *nplanes,
> +			      unsigned int sizes[],
> +			      struct device *alloc_devs[])
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vq);
> +	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> +		 : node->fmt.fmt.meta.buffersize;
> +
> +	if (vq->num_buffers + *nbuffers < 3)

Why 3 ? Are these dummies ?

> +		*nbuffers = 3 - vq->num_buffers;
> +
> +	if (*nplanes) {
> +		if (sizes[0] < size) {
> +			dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> +				sizes[0], size);
> +			return -EINVAL;
> +		}
> +		size = sizes[0];
> +	}
> +
> +	*nplanes = 1;
> +	sizes[0] = size;
> +
> +	return 0;
> +}
> +
> +static int unicam_buffer_prepare(struct vb2_buffer *vb)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> +	struct unicam_buffer *buf = to_unicam_buffer(vb);
> +	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> +		 : node->fmt.fmt.meta.buffersize;
> +
> +	if (vb2_plane_size(vb, 0) < size) {
> +		dev_dbg(node->dev->dev,
> +			"data will not fit into plane (%lu < %u)\n",
> +			vb2_plane_size(vb, 0), size);
> +		return -EINVAL;
> +	}
> +
> +	buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> +	buf->size = size;
> +
> +	vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> +
> +	return 0;
> +}
> +
> +static void unicam_return_buffers(struct unicam_node *node,
> +				  enum vb2_buffer_state state)
> +{
> +	struct unicam_buffer *buf, *tmp;
> +
> +	list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> +		list_del(&buf->list);
> +		vb2_buffer_done(&buf->vb.vb2_buf, state);
> +	}
> +
> +	if (node->cur_frm)
> +		vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> +				state);
> +	if (node->next_frm && node->cur_frm != node->next_frm)
> +		vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> +				state);
> +
> +	node->cur_frm = NULL;
> +	node->next_frm = NULL;
> +}
> +
> +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vq);
> +	struct unicam_device *unicam = node->dev;
> +	struct v4l2_subdev_state *state;
> +	struct unicam_buffer *buf;
> +	unsigned long flags;
> +	int ret;
> +	u32 pad, stream;
> +	u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +					     : UNICAM_SD_PAD_SOURCE_METADATA;
> +
> +	/* Look for the route for the given pad and stream. */
> +	state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +						    remote_pad, 0,
> +						    &pad, &stream);
> +	v4l2_subdev_unlock_state(state);
> +
> +	if (ret)
> +		goto err_return_buffers;
> +
> +	dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> +		unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> +		is_metadata_node(node) ? "metadata" : "image");
> +
> +	/* The metadata node can't be started alone. */
> +	if (is_metadata_node(node)) {
> +		if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {

Does it mean the metadata node has to be started second, or should
this be made a nop and the metadata node gets started once the image
node is started too ? I'm fine with the constraint of having the
metadata node being started second fwiw

> +			dev_err(unicam->dev,
> +				"Can't start metadata without image\n");
> +			ret = -EINVAL;
> +			goto err_return_buffers;
> +		}
> +
> +		spin_lock_irqsave(&node->dma_queue_lock, flags);
> +		buf = list_first_entry(&node->dma_queue,
> +				       struct unicam_buffer, list);
> +		dev_dbg(unicam->dev, "buffer %p\n", buf);

Is this useful ?

> +		node->cur_frm = buf;
> +		node->next_frm = buf;
> +		list_del(&buf->list);
> +		spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> +
> +		unicam_start_metadata(unicam, buf);
> +		node->streaming = true;
> +		return 0;
> +	}
> +
> +	ret = pm_runtime_resume_and_get(unicam->dev);
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> +		goto err_return_buffers;
> +	}
> +
> +	ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> +	if (ret < 0) {
> +		dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);

Isn't this an err ?

> +		goto err_pm_put;
> +	}
> +
> +	spin_lock_irqsave(&node->dma_queue_lock, flags);
> +	buf = list_first_entry(&node->dma_queue,
> +			       struct unicam_buffer, list);
> +	dev_dbg(unicam->dev, "buffer %p\n", buf);
> +	node->cur_frm = buf;
> +	node->next_frm = buf;
> +	list_del(&buf->list);
> +	spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> +
> +	unicam_start_rx(unicam, buf);
> +
> +	ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));

A bit confused by the API here, shouldn't we also do this for embedded
data ?

> +	if (ret < 0) {
> +		dev_err(unicam->dev, "stream on failed in subdev\n");
> +		goto error_pipeline;
> +	}
> +
> +	node->streaming = true;
> +
> +	return 0;
> +
> +error_pipeline:
> +	video_device_pipeline_stop(&node->video_dev);
> +err_pm_put:
> +	pm_runtime_put_sync(unicam->dev);
> +err_return_buffers:
> +	unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> +	return ret;
> +}
> +
> +static void unicam_stop_streaming(struct vb2_queue *vq)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vq);
> +	struct unicam_device *unicam = node->dev;
> +	u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +						   : UNICAM_SD_PAD_SOURCE_METADATA;
> +
> +	node->streaming = false;
> +
> +	v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> +				    BIT(0));
> +
> +	/* We can stream only with the image node. */
> +	if (is_metadata_node(node)) {
> +		/*
> +		 * Allow the hardware to spin in the dummy buffer.
> +		 * This is only really needed if the embedded data pad is
> +		 * disabled before the image pad.
> +		 */
> +		unicam_wr_dma_addr(node, &node->dummy_buf);
> +		goto dequeue_buffers;
> +	}
> +
> +	unicam_disable(unicam);
> +
> +	video_device_pipeline_stop(&node->video_dev);
> +	pm_runtime_put(unicam->dev);
> +
> +dequeue_buffers:
> +	/* Clear all queued buffers for the node */
> +	unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> +}
> +
> +static void unicam_buffer_queue(struct vb2_buffer *vb)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> +	struct unicam_buffer *buf = to_unicam_buffer(vb);
> +
> +	spin_lock_irq(&node->dma_queue_lock);
> +	list_add_tail(&buf->list, &node->dma_queue);
> +	spin_unlock_irq(&node->dma_queue_lock);
> +}
> +
> +static const struct vb2_ops unicam_video_qops = {
> +	.queue_setup		= unicam_queue_setup,
> +	.wait_prepare		= vb2_ops_wait_prepare,
> +	.wait_finish		= vb2_ops_wait_finish,
> +	.buf_prepare		= unicam_buffer_prepare,
> +	.start_streaming	= unicam_start_streaming,
> +	.stop_streaming		= unicam_stop_streaming,
> +	.buf_queue		= unicam_buffer_queue,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + *  V4L2 video device operations
> + */
> +
> +static int unicam_querycap(struct file *file, void *priv,
> +			   struct v4l2_capability *cap)
> +{
> +	strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> +	strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> +
> +	cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> +
> +	return 0;
> +}
> +
> +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> +			       struct v4l2_fmtdesc *f)
> +{
> +	unsigned int index;
> +	unsigned int i;
> +
> +	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> +		if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> +			continue;
> +
> +		if (index == f->index) {
> +			f->pixelformat = unicam_image_formats[i].fourcc;
> +			return 0;
> +		}
> +
> +		index++;
> +
> +		if (!unicam_image_formats[i].unpacked_fourcc)
> +			continue;
> +
> +		if (index == f->index) {
> +			f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> +			return 0;
> +		}
> +
> +		index++;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int unicam_g_fmt_vid(struct file *file, void *priv,
> +			    struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	*f = node->fmt;
> +
> +	return 0;
> +}
> +
> +static const struct unicam_format_info *
> +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> +{
> +	const struct unicam_format_info *fmtinfo;
> +
> +	/*
> +	 * Default to the first format if the requested pixel format code isn't
> +	 * supported.
> +	 */
> +	fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> +					       UNICAM_SD_PAD_SOURCE_IMAGE);
> +	if (!fmtinfo) {
> +		fmtinfo = &unicam_image_formats[0];
> +		pix->pixelformat = fmtinfo->fourcc;
> +	}
> +
> +	unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> +
> +	if (pix->field == V4L2_FIELD_ANY)
> +		pix->field = V4L2_FIELD_NONE;
> +
> +	return fmtinfo;
> +}
> +
> +static int unicam_try_fmt_vid(struct file *file, void *priv,
> +			      struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	__unicam_try_fmt_vid(node, &f->fmt.pix);
> +	return 0;
> +}
> +
> +static int unicam_s_fmt_vid(struct file *file, void *priv,
> +			    struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	if (vb2_is_busy(&node->buffer_queue))
> +		return -EBUSY;
> +
> +	node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> +	node->fmt = *f;
> +
> +	return 0;
> +}
> +
> +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> +				struct v4l2_fmtdesc *f)
> +{
> +	unsigned int i, index;
> +
> +	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> +		if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)

Do we want to allow mbus_code filtering for metadata ? There's a
1-to-1 relationship between mbus codes and pixel formats

> +			continue;
> +		if (!unicam_meta_formats[i].metadata_fmt)
> +			continue;

How can this be false if we're iterating on unicam_meta_formats[] ?

> +
> +		if (index == f->index) {
> +			f->pixelformat = unicam_meta_formats[i].fourcc;
> +			f->type = V4L2_BUF_TYPE_META_CAPTURE;
> +			return 0;
> +		}
> +		index++;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int unicam_g_fmt_meta(struct file *file, void *priv,
> +			     struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	f->fmt.meta = node->fmt.fmt.meta;
> +
> +	return 0;
> +}
> +
> +static const struct unicam_format_info *
> +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> +{
> +	const struct unicam_format_info *fmtinfo;
> +
> +	/*
> +	 * Default to the first format if the requested pixel format code isn't
> +	 * supported.
> +	 */
> +	fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> +					       UNICAM_SD_PAD_SOURCE_METADATA);
> +	if (!fmtinfo) {
> +		fmtinfo = &unicam_meta_formats[0];
> +		meta->dataformat = fmtinfo->fourcc;
> +	}
> +
> +	unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> +
> +	return fmtinfo;
> +}
> +
> +static int unicam_try_fmt_meta(struct file *file, void *priv,
> +			       struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	__unicam_try_fmt_vid(node, &f->fmt.pix);
> +	return 0;
> +}
> +
> +static int unicam_s_fmt_meta(struct file *file, void *priv,
> +			     struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	if (vb2_is_busy(&node->buffer_queue))
> +		return -EBUSY;
> +
> +	node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> +	node->fmt = *f;
> +
> +	return 0;
> +}
> +
> +static int unicam_enum_framesizes(struct file *file, void *fh,
> +				  struct v4l2_frmsizeenum *fsize)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +	int ret = -EINVAL;
> +
> +	if (fsize->index > 0)
> +		return ret;
> +
> +	if (is_image_node(node)) {
> +		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> +						  UNICAM_SD_PAD_SOURCE_IMAGE))
> +			return ret;
> +
> +		fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> +		fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> +		fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> +		fsize->stepwise.step_width = 1;
> +		fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> +		fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> +		fsize->stepwise.step_height = 1;
> +	} else {
> +		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> +						  UNICAM_SD_PAD_SOURCE_METADATA))
> +			return ret;
> +
Isn't this V4L2_FRMSIZE_TYPE_STEPWISE as well ?

> +		fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> +		fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> +		fsize->stepwise.step_width = 1;
> +		fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> +		fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> +		fsize->stepwise.step_height = 1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_log_status(struct file *file, void *fh)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +	struct unicam_device *unicam = node->dev;
> +	u32 reg;
> +
> +	/* status for sub devices */
> +	v4l2_device_call_all(&unicam->v4l2_dev, 0, core, log_status);
> +
> +	dev_info(unicam->dev, "-----Receiver status-----\n");
> +	dev_info(unicam->dev, "V4L2 width/height:   %ux%u\n",
> +		 node->fmt.fmt.pix.width, node->fmt.fmt.pix.height);
> +	dev_info(unicam->dev, "Mediabus format:     %08x\n",
> +		 node->fmtinfo->code);
> +	dev_info(unicam->dev, "V4L2 format:         %08x\n",
> +		 node->fmt.fmt.pix.pixelformat);
> +	reg = unicam_reg_read(unicam, UNICAM_IPIPE);
> +	dev_info(unicam->dev, "Unpacking/packing:   %u / %u\n",
> +		 unicam_get_field(reg, UNICAM_PUM_MASK),
> +		 unicam_get_field(reg, UNICAM_PPM_MASK));
> +	dev_info(unicam->dev, "----Live data----\n");
> +	dev_info(unicam->dev, "Programmed stride:   %4u\n",
> +		 unicam_reg_read(unicam, UNICAM_IBLS));
> +	dev_info(unicam->dev, "Detected resolution: %ux%u\n",
> +		 unicam_reg_read(unicam, UNICAM_IHSTA),
> +		 unicam_reg_read(unicam, UNICAM_IVSTA));
> +	dev_info(unicam->dev, "Write pointer:       %08x\n",
> +		 unicam_reg_read(unicam, UNICAM_IBWP));
> +
> +	return 0;
> +}
> +
> +static int unicam_subscribe_event(struct v4l2_fh *fh,
> +				  const struct v4l2_event_subscription *sub)
> +{
> +	switch (sub->type) {
> +	case V4L2_EVENT_FRAME_SYNC:
> +		return v4l2_event_subscribe(fh, sub, 2, NULL);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const struct v4l2_ioctl_ops unicam_ioctl_ops = {
> +	.vidioc_querycap		= unicam_querycap,
> +
> +	.vidioc_enum_fmt_vid_cap	= unicam_enum_fmt_vid,
> +	.vidioc_g_fmt_vid_cap		= unicam_g_fmt_vid,
> +	.vidioc_try_fmt_vid_cap		= unicam_try_fmt_vid,
> +	.vidioc_s_fmt_vid_cap		= unicam_s_fmt_vid,
> +
> +	.vidioc_enum_fmt_meta_cap	= unicam_enum_fmt_meta,
> +	.vidioc_g_fmt_meta_cap		= unicam_g_fmt_meta,
> +	.vidioc_try_fmt_meta_cap	= unicam_try_fmt_meta,
> +	.vidioc_s_fmt_meta_cap		= unicam_s_fmt_meta,
> +
> +	.vidioc_enum_framesizes		= unicam_enum_framesizes,
> +
> +	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
> +	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
> +	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
> +	.vidioc_querybuf		= vb2_ioctl_querybuf,
> +	.vidioc_qbuf			= vb2_ioctl_qbuf,
> +	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
> +	.vidioc_expbuf			= vb2_ioctl_expbuf,
> +	.vidioc_streamon		= vb2_ioctl_streamon,
> +	.vidioc_streamoff		= vb2_ioctl_streamoff,
> +
> +	.vidioc_log_status		= unicam_log_status,
> +	.vidioc_subscribe_event		= unicam_subscribe_event,
> +	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
> +};
> +
> +/* unicam capture driver file operations */
> +static const struct v4l2_file_operations unicam_fops = {
> +	.owner		= THIS_MODULE,
> +	.open           = v4l2_fh_open,
> +	.release        = vb2_fop_release,
> +	.poll		= vb2_fop_poll,
> +	.unlocked_ioctl = video_ioctl2,
> +	.mmap           = vb2_fop_mmap,
> +};
> +
> +static int unicam_video_link_validate(struct media_link *link)
> +{
> +	struct video_device *vdev =
> +		media_entity_to_video_device(link->sink->entity);
> +	struct v4l2_subdev *sd =
> +		media_entity_to_v4l2_subdev(link->source->entity);
> +	struct unicam_node *node = video_get_drvdata(vdev);
> +	const u32 pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +		      : UNICAM_SD_PAD_SOURCE_METADATA;
> +	const struct v4l2_mbus_framefmt *format;
> +	struct v4l2_subdev_state *state;
> +	int ret = 0;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> +	format = v4l2_subdev_state_get_format(state, pad, 0);
> +	if (!format) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (is_image_node(node)) {
> +		const struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> +
> +		if (node->fmtinfo->code != format->code ||
> +		    fmt->height != format->height ||
> +		    fmt->width != format->width ||
> +		    fmt->field != format->field) {
> +			dev_dbg(node->dev->dev,
> +				"image: (%u x %u) 0x%08x %s != (%u x %u) 0x%08x %s\n",
> +				fmt->width, fmt->height, node->fmtinfo->code,
> +				v4l2_field_names[fmt->field],
> +				format->width, format->height, format->code,
> +				v4l2_field_names[format->field]);
> +			ret = -EPIPE;
> +		};

No need for ; here and in the next loop

> +	} else {
> +		const struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> +
> +		if (node->fmtinfo->code != format->code ||
> +		    fmt->height != format->height ||
> +		    fmt->width != format->width) {
> +			dev_dbg(node->dev->dev,
> +				"meta: (%u x %u) 0x%04x != (%u x %u) 0x%04x\n",
> +				fmt->width, fmt->height, node->fmtinfo->code,
> +				format->width, format->height, format->code);
> +			ret = -EPIPE;
> +		};
> +	}
> +
> +out:
> +	v4l2_subdev_unlock_state(state);
> +	return ret;
> +}
> +
> +static const struct media_entity_operations unicam_video_media_ops = {
> +	.link_validate = unicam_video_link_validate,
> +};
> +
> +static void unicam_node_release(struct video_device *vdev)
> +{
> +	struct unicam_node *node = video_get_drvdata(vdev);
> +
> +	unicam_put(node->dev);
> +}
> +
> +static void unicam_set_default_format(struct unicam_node *node)
> +{
> +	if (is_image_node(node)) {
> +		struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> +
> +		node->fmtinfo = &unicam_image_formats[0];
> +		node->fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +
> +		v4l2_fill_pix_format(fmt, &unicam_default_image_format);
> +		fmt->pixelformat = node->fmtinfo->fourcc;
> +		unicam_calc_image_size_bpl(node->dev, node->fmtinfo, fmt);
> +	} else {
> +		struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> +
> +		node->fmtinfo = &unicam_meta_formats[0];
> +		node->fmt.type = V4L2_BUF_TYPE_META_CAPTURE;
> +
> +		fmt->dataformat = node->fmtinfo->fourcc;
> +		fmt->width = unicam_default_meta_format.width;
> +		fmt->height = unicam_default_meta_format.height;
> +		unicam_calc_meta_size_bpl(node->dev, node->fmtinfo, fmt);
> +	}
> +}
> +
> +static int unicam_register_node(struct unicam_device *unicam,
> +				enum unicam_node_type type)
> +{
> +	const u32 pad_index = type == UNICAM_IMAGE_NODE
> +			    ? UNICAM_SD_PAD_SOURCE_IMAGE
> +			    : UNICAM_SD_PAD_SOURCE_METADATA;
> +	struct unicam_node *node = &unicam->node[type];
> +	struct video_device *vdev = &node->video_dev;
> +	struct vb2_queue *q = &node->buffer_queue;
> +	int ret;
> +
> +	node->dev = unicam_get(unicam);
> +	node->id = type;
> +
> +	spin_lock_init(&node->dma_queue_lock);
> +	mutex_init(&node->lock);
> +
> +	INIT_LIST_HEAD(&node->dma_queue);
> +
> +	/* Initialize the videobuf2 queue. */
> +	q->type = type == UNICAM_IMAGE_NODE ? V4L2_BUF_TYPE_VIDEO_CAPTURE
> +					    : V4L2_BUF_TYPE_META_CAPTURE;
> +	q->io_modes = VB2_MMAP | VB2_DMABUF;
> +	q->drv_priv = node;
> +	q->ops = &unicam_video_qops;
> +	q->mem_ops = &vb2_dma_contig_memops;
> +	q->buf_struct_size = sizeof(struct unicam_buffer);
> +	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> +	q->lock = &node->lock;
> +	q->min_queued_buffers = 1;
> +	q->dev = unicam->dev;
> +
> +	ret = vb2_queue_init(q);
> +	if (ret) {
> +		dev_err(unicam->dev, "vb2_queue_init() failed\n");
> +		goto err_unicam_put;
> +	}
> +
> +	/* Initialize the video device. */
> +	vdev->release = unicam_node_release;
> +	vdev->fops = &unicam_fops;
> +	vdev->ioctl_ops = &unicam_ioctl_ops;
> +	vdev->v4l2_dev = &unicam->v4l2_dev;
> +	vdev->vfl_dir = VFL_DIR_RX;
> +	vdev->queue = q;
> +	vdev->lock = &node->lock;
> +	vdev->device_caps = type == UNICAM_IMAGE_NODE
> +			  ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_META_CAPTURE;
> +	vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
> +	vdev->entity.ops = &unicam_video_media_ops;
> +
> +	snprintf(vdev->name, sizeof(vdev->name), "%s-%s", UNICAM_MODULE_NAME,
> +		 type == UNICAM_IMAGE_NODE ? "image" : "embedded");
> +
> +	video_set_drvdata(vdev, node);
> +
> +	if (type == UNICAM_IMAGE_NODE)
> +		vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
> +
> +	node->pad.flags = MEDIA_PAD_FL_SINK;
> +
> +	ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
> +	if (ret)
> +		goto err_unicam_put;
> +
> +	node->dummy_buf.size = UNICAM_DUMMY_BUF_SIZE;
> +	node->dummy_buf_cpu_addr = dma_alloc_coherent(unicam->dev,
> +						      node->dummy_buf.size,
> +						      &node->dummy_buf.dma_addr,
> +						      GFP_KERNEL);
> +	if (!node->dummy_buf_cpu_addr) {
> +		dev_err(unicam->dev, "Unable to allocate dummy buffer.\n");
> +		ret = -ENOMEM;
> +		goto err_entity_cleanup;
> +	}
> +
> +	unicam_set_default_format(node);
> +
> +	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register video device %s\n",
> +			vdev->name);
> +		goto err_dma_free;
> +	}
> +
> +	node->registered = true;
> +
> +	ret = media_create_pad_link(&unicam->subdev.sd.entity,
> +				    pad_index,
> +				    &node->video_dev.entity,
> +				    0,
> +				    MEDIA_LNK_FL_ENABLED |
> +				    MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret) {
> +		/*
> +		 * No need for cleanup, the caller will unregister the
> +		 * video device, which will drop the reference on the
> +		 * device and trigger the cleanup.
> +		 */
> +		dev_err(unicam->dev, "Unable to create pad link for %s\n",
> +			unicam->sensor.subdev->name);
> +		return ret;
> +	}
> +
> +	return 0;
> +
> +err_dma_free:
> +	dma_free_coherent(unicam->dev, node->dummy_buf.size,
> +			  node->dummy_buf_cpu_addr,
> +			  node->dummy_buf.dma_addr);
> +err_entity_cleanup:
> +	media_entity_cleanup(&vdev->entity);
> +err_unicam_put:
> +	unicam_put(unicam);
> +	return ret;
> +}
> +
> +static void unicam_unregister_nodes(struct unicam_device *unicam)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +		struct unicam_node *node = &unicam->node[i];
> +
> +		if (node->dummy_buf_cpu_addr)
> +			dma_free_coherent(unicam->dev, node->dummy_buf.size,
> +					  node->dummy_buf_cpu_addr,
> +					  node->dummy_buf.dma_addr);
> +
> +		if (node->registered) {
> +			video_unregister_device(&node->video_dev);
> +			node->registered = false;
> +		}
> +	}
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Power management
> + */
> +
> +static int unicam_runtime_resume(struct device *dev)
> +{
> +	struct unicam_device *unicam = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = clk_set_min_rate(unicam->vpu_clock, UNICAM_MIN_VPU_CLOCK_RATE);
> +	if (ret) {
> +		dev_err(unicam->dev, "failed to set up VPU clock\n");
> +		return ret;
> +	}

Same question as above, shouldn't this be an 'assigned-clock-rates in
dts ?

> +
> +	ret = clk_prepare_enable(unicam->vpu_clock);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to enable VPU clock: %d\n", ret);
> +		goto err_vpu_clock;
> +	}
> +
> +	ret = clk_set_rate(unicam->clock, 100 * 1000 * 1000);
> +	if (ret) {
> +		dev_err(unicam->dev, "failed to set up CSI clock\n");
> +		goto err_vpu_prepare;
> +	}

same question

> +
> +	ret = clk_prepare_enable(unicam->clock);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to enable CSI clock: %d\n", ret);
> +		goto err_vpu_prepare;

Do you need to 'unset' the rate as done for the VPU clock ?

> +	}
> +
> +	return 0;
> +
> +err_vpu_prepare:
> +	clk_disable_unprepare(unicam->vpu_clock);
> +err_vpu_clock:
> +	if (clk_set_min_rate(unicam->vpu_clock, 0))
> +		dev_err(unicam->dev, "failed to reset the VPU clock\n");
> +
> +	return ret;
> +}
> +
> +static int unicam_runtime_suspend(struct device *dev)
> +{
> +	struct unicam_device *unicam = dev_get_drvdata(dev);
> +
> +	clk_disable_unprepare(unicam->clock);

(continuing  with the above question: probably not, as the clock is
not 'unset' neither here)

The rest looks good, nice to see this progressing!

Thanks
  j

> +
> +	if (clk_set_min_rate(unicam->vpu_clock, 0))
> +		dev_err(unicam->dev, "failed to reset the VPU clock\n");
> +
> +	clk_disable_unprepare(unicam->vpu_clock);
> +
> +	return 0;
> +}
> +
> +static const struct dev_pm_ops unicam_pm_ops = {
> +	RUNTIME_PM_OPS(unicam_runtime_suspend, unicam_runtime_resume, NULL)
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * V4L2 async notifier
> + */
> +
> +static int unicam_async_bound(struct v4l2_async_notifier *notifier,
> +			      struct v4l2_subdev *subdev,
> +			      struct v4l2_async_connection *asc)
> +{
> +	struct unicam_device *unicam = notifier_to_unicam_device(notifier);
> +	struct media_pad *sink = &unicam->subdev.pads[UNICAM_SD_PAD_SINK];
> +	struct media_pad *source;
> +	int ret;
> +
> +	dev_dbg(unicam->dev, "Using sensor %s for capture\n",
> +		subdev->name);
> +
> +	ret = v4l2_create_fwnode_links_to_pad(subdev, sink, MEDIA_LNK_FL_ENABLED |
> +					      MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret)
> +		return ret;
> +
> +	source = media_pad_remote_pad_unique(sink);
> +	if (!source) {
> +		dev_err(unicam->dev, "No connected sensor pad\n");
> +		return -ENOTCONN;
> +	}
> +
> +	unicam->sensor.subdev = subdev;
> +	unicam->sensor.pad = source;
> +
> +	return 0;
> +}
> +
> +static int unicam_async_complete(struct v4l2_async_notifier *notifier)
> +{
> +	struct unicam_device *unicam = notifier_to_unicam_device(notifier);
> +	int ret;
> +
> +	ret = unicam_register_node(unicam, UNICAM_IMAGE_NODE);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register image video device.\n");
> +		goto unregister;
> +	}
> +
> +	ret = unicam_register_node(unicam, UNICAM_METADATA_NODE);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register metadata video device.\n");
> +		goto unregister;
> +	}
> +
> +	ret = v4l2_device_register_subdev_nodes(&unicam->v4l2_dev);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register subdev nodes.\n");
> +		goto unregister;
> +	}
> +
> +	return 0;
> +
> +unregister:
> +	unicam_unregister_nodes(unicam);
> +	unicam_put(unicam);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_async_notifier_operations unicam_async_ops = {
> +	.bound = unicam_async_bound,
> +	.complete = unicam_async_complete,
> +};
> +
> +static int unicam_async_nf_init(struct unicam_device *unicam)
> +{
> +	struct v4l2_fwnode_endpoint ep = { };
> +	struct fwnode_handle *ep_handle;
> +	struct v4l2_async_connection *asc;
> +	int ret;
> +
> +	ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
> +				   &unicam->max_data_lanes);
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "Missing %s DT property\n",
> +			"brcm,num-data-lanes");
> +		return -EINVAL;
> +	}
> +
> +	/* Get and parse the local endpoint. */
> +	ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
> +						    FWNODE_GRAPH_ENDPOINT_NEXT);
> +	if (!ep_handle) {
> +		dev_err(unicam->dev, "No endpoint found\n");
> +		return -ENODEV;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
> +		goto error;
> +	}
> +
> +	unicam->bus_type = ep.bus_type;
> +
> +	switch (ep.bus_type) {
> +	case V4L2_MBUS_CSI2_DPHY: {
> +		unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
> +
> +		if (num_data_lanes != 1 && num_data_lanes != 2 &&
> +		    num_data_lanes != 4) {
> +			dev_err(unicam->dev, "%u data lanes not supported\n",
> +				num_data_lanes);
> +			goto error;
> +		}
> +
> +		if (num_data_lanes > unicam->max_data_lanes) {
> +			dev_err(unicam->dev,
> +				"Endpoint uses %u data lanes when %u are supported\n",
> +				num_data_lanes, unicam->max_data_lanes);
> +			goto error;
> +		}
> +
> +		unicam->active_data_lanes = num_data_lanes;
> +		unicam->bus_flags = ep.bus.mipi_csi2.flags;
> +		break;
> +	}
> +
> +	case V4L2_MBUS_CCP2:
> +		unicam->max_data_lanes = 1;
> +		unicam->active_data_lanes = 1;
> +		unicam->bus_flags = ep.bus.mipi_csi1.strobe;
> +		break;
> +
> +	default:
> +		/* Unsupported bus type */
> +		dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
> +		goto error;
> +	}
> +
> +	/* Initialize and register the async notifier. */
> +	v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
> +
> +	asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
> +					      struct v4l2_async_connection);
> +	fwnode_handle_put(ep_handle);
> +	ep_handle = NULL;
> +
> +	if (IS_ERR(asc)) {
> +		ret = PTR_ERR(asc);
> +		dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
> +			ret);
> +		goto error;
> +	}
> +
> +	unicam->notifier.ops = &unicam_async_ops;
> +
> +	ret = v4l2_async_nf_register(&unicam->notifier);
> +	if (ret) {
> +		dev_err(unicam->dev, "Error registering device notifier: %d\n",
> +			ret);
> +		goto error;
> +	}
> +
> +	return 0;
> +
> +error:
> +	fwnode_handle_put(ep_handle);
> +	return ret;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Probe & remove
> + */
> +
> +static int unicam_media_init(struct unicam_device *unicam)
> +{
> +	int ret;
> +
> +	unicam->mdev.dev = unicam->dev;
> +	strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
> +		sizeof(unicam->mdev.model));
> +	strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));
> +	unicam->mdev.hw_revision = 0;
> +
> +	media_device_init(&unicam->mdev);
> +
> +	unicam->v4l2_dev.mdev = &unicam->mdev;
> +
> +	ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "Unable to register v4l2 device\n");
> +		goto err_media_cleanup;
> +	}
> +
> +	ret = media_device_register(&unicam->mdev);
> +	if (ret < 0) {
> +		dev_err(unicam->dev,
> +			"Unable to register media-controller device\n");
> +		goto err_v4l2_unregister;
> +	}
> +
> +	return 0;
> +
> +err_v4l2_unregister:
> +	v4l2_device_unregister(&unicam->v4l2_dev);
> +err_media_cleanup:
> +	media_device_cleanup(&unicam->mdev);
> +	return ret;
> +}
> +
> +static int unicam_probe(struct platform_device *pdev)
> +{
> +	struct unicam_device *unicam;
> +	int ret;
> +
> +	unicam = kzalloc(sizeof(*unicam), GFP_KERNEL);
> +	if (!unicam)
> +		return -ENOMEM;
> +
> +	kref_init(&unicam->kref);
> +	unicam->dev = &pdev->dev;
> +	platform_set_drvdata(pdev, unicam);
> +
> +	unicam->base = devm_platform_ioremap_resource_byname(pdev, "unicam");
> +	if (IS_ERR(unicam->base)) {
> +		ret = PTR_ERR(unicam->base);
> +		goto err_unicam_put;
> +	}
> +
> +	unicam->clk_gate_base = devm_platform_ioremap_resource_byname(pdev, "cmi");
> +	if (IS_ERR(unicam->clk_gate_base)) {
> +		ret = PTR_ERR(unicam->clk_gate_base);
> +		goto err_unicam_put;
> +	}
> +
> +	unicam->clock = devm_clk_get(&pdev->dev, "lp");
> +	if (IS_ERR(unicam->clock)) {
> +		dev_err(unicam->dev, "Failed to get lp clock\n");
> +		ret = PTR_ERR(unicam->clock);
> +		goto err_unicam_put;
> +	}
> +
> +	unicam->vpu_clock = devm_clk_get(&pdev->dev, "vpu");
> +	if (IS_ERR(unicam->vpu_clock)) {
> +		dev_err(unicam->dev, "Failed to get vpu clock\n");
> +		ret = PTR_ERR(unicam->vpu_clock);
> +		goto err_unicam_put;
> +	}
> +
> +	ret = platform_get_irq(pdev, 0);
> +	if (ret <= 0) {
> +		dev_err(&pdev->dev, "No IRQ resource\n");
> +		ret = -EINVAL;
> +		goto err_unicam_put;
> +	}
> +
> +	ret = devm_request_irq(&pdev->dev, ret, unicam_isr, 0,
> +			       "unicam_capture0", unicam);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Unable to request interrupt\n");
> +		ret = -EINVAL;
> +		goto err_unicam_put;
> +	}
> +
> +	/* Enable the block power domain. */
> +	pm_runtime_enable(&pdev->dev);
> +
> +	ret = unicam_media_init(unicam);
> +	if (ret)
> +		goto err_pm_runtime;
> +
> +	ret = unicam_subdev_init(unicam);
> +	if (ret)
> +		goto err_media_unregister;
> +
> +	ret = unicam_async_nf_init(unicam);
> +	if (ret)
> +		goto err_subdev_unregister;
> +
> +	return 0;
> +
> +err_subdev_unregister:
> +	unicam_subdev_cleanup(unicam);
> +err_media_unregister:
> +	media_device_unregister(&unicam->mdev);
> +err_pm_runtime:
> +	pm_runtime_disable(&pdev->dev);
> +err_unicam_put:
> +	unicam_put(unicam);
> +
> +	return ret;
> +}
> +
> +static int unicam_remove(struct platform_device *pdev)
> +{
> +	struct unicam_device *unicam = platform_get_drvdata(pdev);
> +
> +	unicam_unregister_nodes(unicam);
> +	v4l2_device_unregister(&unicam->v4l2_dev);
> +	media_device_unregister(&unicam->mdev);
> +	v4l2_async_nf_unregister(&unicam->notifier);
> +
> +	unicam_subdev_cleanup(unicam);
> +
> +	unicam_put(unicam);
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id unicam_of_match[] = {
> +	{ .compatible = "brcm,bcm2835-unicam", },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, unicam_of_match);
> +
> +static struct platform_driver unicam_driver = {
> +	.probe		= unicam_probe,
> +	.remove		= unicam_remove,
> +	.driver = {
> +		.name	= UNICAM_MODULE_NAME,
> +		.pm	= pm_ptr(&unicam_pm_ops),
> +		.of_match_table = of_match_ptr(unicam_of_match),
> +	},
> +};
> +
> +module_platform_driver(unicam_driver);
> +
> +MODULE_AUTHOR("Dave Stevenson <[e-mail]>");
> +MODULE_DESCRIPTION("BCM2835 Unicam driver");
> +MODULE_LICENSE("GPL");
> --
> Regards,
>
> Laurent Pinchart
>
>

Laurent Pinchart March 4, 2024, 7:51 p.m. UTC | #2

Hi Jacopo,

On Mon, Mar 04, 2024 at 06:12:21PM +0100, Jacopo Mondi wrote:
> On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > From: Dave Stevenson <[e-mail]>
> >
> > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > It is represented as two video device nodes: unicam-image and
> > unicam-embedded which are connected to an internal subdev (named
> > unicam-subdev) in order to manage streams routing.
> >
> > Signed-off-by: Dave Stevenson <[e-mail]>
> > Co-developed-by: Naushir Patuck <[e-mail]>
> > Signed-off-by: Naushir Patuck <[e-mail]>
> > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > Co-developed-by: Laurent Pinchart <[e-mail]>
> > Signed-off-by: Laurent Pinchart <[e-mail]>
> > ---
> > Changes since v5:
> >
> > - Move to drivers/media/platform/broadcom/
> > - Port to the upstream V4L2 streams API
> > - Rebase on latest metadata API proposal
> > - Add missing error message
> > - Drop unneeded documentation block for unicam_isr()
> > - Drop unneeded dev_dbg() and dev_err() messages
> > - Drop unneeded streams_mask and fmt checks
> > - Drop unused unicam_sd_pad_is_sink()
> > - Drop unneeded includes
> > - Drop v4l2_ctrl_subscribe_event() call
> > - Use pm_runtime_resume_and_get()
> > - Indentation and line wrap fixes
> > - Let the framework set bus_info
> > - Use v4l2_fwnode_endpoint_parse()
> > - Fix media device cleanup
> > - Drop lane reordering checks
> > - Fix subdev state locking
> > - Drop extra debug messages
> > - Move clock handling to runtime PM handlers
> > - Reorder functions
> > - Rename init functions for more clarity
> > - Initialize runtime PM earlier
> > - Clarify error messages
> > - Simplify subdev init with local variable
> > - Fix subdev cleanup
> > - Fix typos and indentation
> > - Don't initialize local variables needlessly
> > - Simplify num lanes check
> > - Fix metadata handling in subdev set_fmt
> > - Drop manual fallback to .s_stream()
> > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > - Simplify unicam_set_default_format()
> > - Fix default format settings
> > - Add busy check in unicam_s_fmt_meta()
> > - Add missing \n at end of format strings
> > - Fix metadata handling in subdev set_fmt
> > - Fix locking when starting streaming
> > - Return buffers from start streaming fails
> > - Fix format validation for metadata node
> > - Use video_device_pipeline_{start,stop}() helpers
> > - Simplify format enumeration
> > - Drop unset variable
> > - Update MAINTAINERS entry
> > - Update to the upstream v4l2_async_nf API
> > - Update to the latest subdev routing API
> > - Update to the latest subdev state API
> > - Move from subdev .init_cfg() to .init_state()
> > - Update to the latest videobuf2 API
> > - Fix v4l2_subdev_enable_streams() error check
> > - Use correct pad for the connected subdev
> > - Return buffers to vb2 when start streaming fails
> > - Improve debugging in start streaming handler
> > - Simplify DMA address management
> > - Drop comment about bcm2835-camera driver
> > - Clarify comments that explain min/max sizes
> > - Pass v4l2_pix_format to unicam_try_fmt()
> > - Drop unneeded local variables
> > - Rename image-related constants and functions
> > - Turn unicam_fmt.metadata_fmt into bool
> > - Rename unicam_fmt to unicam_format_info
> > - Rename unicam_format_info variables to fmtinfo
> > - Rename unicam_node.v_fmt to fmt
> > - Add metadata formats for RAW10, RAW12 and RAW14
> > - Make metadata formats line-based
> > - Validate format on metadata video device
> > - Add Co-devlopped-by tags
> >
> > Changes since v3:
> >
> > - Add the vendor prefix for DT name
> > - Use the reg-names in DT parsing
> > - Remove MAINTAINERS entry
> >
> > Changes since v2:
> >
> > - Change code organization
> > - Remove unused variables
> > - Correct the fmt_meta functions
> > - Rewrite the start/stop streaming
> >   - You can now start the image node alone, but not the metadata one
> >   - The buffers are allocated per-node
> >   - only the required stream is started, if the route exists and is
> >     enabled
> > - Prefix the macros with UNICAM_ to not have too generic names
> > - Drop colorspace support
> >
> > Changes since v1:
> >
> > - Replace the unicam_{info,debug,error} macros with dev_*()
> > ---
> >  MAINTAINERS                                   |    1 +
> >  drivers/media/platform/Kconfig                |    1 +
> >  drivers/media/platform/Makefile               |    1 +
> >  drivers/media/platform/broadcom/Kconfig       |   23 +
> >  drivers/media/platform/broadcom/Makefile      |    3 +
> >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> >  7 files changed, 2891 insertions(+)
> >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> >  create mode 100644 drivers/media/platform/broadcom/Makefile
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c

[snip]

> > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > new file mode 100644
> > index 000000000000..716c89b8a217
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > @@ -0,0 +1,2607 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * BCM283x / BCM271x Unicam Capture Driver
> > + *
> > + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> > + *
> > + * Dave Stevenson <[e-mail]>
> > + *
> > + * Based on TI am437x driver by
> > + *   Benoit Parrot <[e-mail]>
> > + *   Lad, Prabhakar <[e-mail]>
> > + *
> > + * and TI CAL camera interface driver by
> > + *    Benoit Parrot <[e-mail]>
> > + *
> > + *
> > + * There are two camera drivers in the kernel for BCM283x - this one and
> > + * bcm2835-camera (currently in staging).
> > + *
> > + * This driver directly controls the Unicam peripheral - there is no
> > + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> > + * and writes it into SDRAM. The only potential processing options are to
> > + * repack Bayer data into an alternate format, and applying windowing. The
> > + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> > + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> > + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> > + * where the relevant formats are defined, and will automatically configure the
> > + * repacking as required. Support for windowing may be added later.
> 
> Does this last paragraph applies ? I see all the supported packed raw
> format having an 'unpacked_fourcc' associated (all but the 8 bit ones
> ofc)

Maybe I'm tired, but I'm not sure to understand why you think it may not
apply.

> > + *
> > + * It should be possible to connect this driver to any sensor with a suitable
> > + * output interface and V4L2 subdevice driver.
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/device.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/err.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/slab.h>
> > +#include <linux/videodev2.h>
> > +
> > +#include <media/v4l2-async.h>
> > +#include <media/v4l2-common.h>
> > +#include <media/v4l2-dev.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/v4l2-ioctl.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-mc.h>
> > +#include <media/videobuf2-dma-contig.h>
> > +
> > +#include "bcm2835-unicam-regs.h"
> > +
> > +#define UNICAM_MODULE_NAME		"unicam"
> > +
> > +/*
> > + * Unicam must request a minimum of 250Mhz from the VPU clock.
> > + * Otherwise the input FIFOs overrun and cause image corruption.
> > + */
> > +#define UNICAM_MIN_VPU_CLOCK_RATE	(250 * 1000 * 1000)
> 
> Shouldn't this be set in DT ?

With assigned-clock-rates ? Then the clock would always run at 250MHz
(or higher, depending on the rate in the DT), while the driver ensures
it runs at at least 250MHz only when the device is being used.

> > +
> > +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> > +#define UNICAM_DMA_BPL_ALIGNMENT	16
> > +
> > +/*
> > + * The image stride is stored in a 16 bit register, and needs to be aligned to
> > + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> > + * constraint on its input, set the image stride alignment to 32 bytes here as
> > + * well to avoid incompatible configurations.
> > + */
> > +#define UNICAM_IMAGE_BPL_ALIGNMENT	32
> > +#define UNICAM_IMAGE_MAX_BPL		((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
> > +
> > +/*
> > + * Max width is therefore determined by the max stride divided by the number of
> > + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> > + * so adopt a square image for want of anything better.
> > + */
> > +#define UNICAM_IMAGE_MIN_WIDTH		16
> > +#define UNICAM_IMAGE_MIN_HEIGHT		16
> > +#define UNICAM_IMAGE_MAX_WIDTH		(UNICAM_IMAGE_MAX_BPL / 4)
> > +#define UNICAM_IMAGE_MAX_HEIGHT		UNICAM_IMAGE_MAX_WIDTH
> > +
> > +/*
> > + * There's no intrinsic limits on the width and height for embedded dat. Use
> > + * the same maximum values as for the image, to avoid overflows in the image
> > + * size computation.
> > + */
> > +#define UNICAM_META_MIN_WIDTH		1
> > +#define UNICAM_META_MIN_HEIGHT		1
> > +#define UNICAM_META_MAX_WIDTH		UNICAM_IMAGE_MAX_WIDTH
> > +#define UNICAM_META_MAX_HEIGHT		UNICAM_IMAGE_MAX_HEIGHT
> > +
> > +/*
> > + * Size of the dummy buffer. Can be any size really, but the DMA
> > + * allocation works in units of page sizes.
> > + */
> > +#define UNICAM_DUMMY_BUF_SIZE		PAGE_SIZE
> > +
> > +#define UNICAM_SD_PAD_SINK		0
> > +#define UNICAM_SD_PAD_SOURCE_IMAGE	1
> > +#define UNICAM_SD_PAD_SOURCE_METADATA	2
> > +#define UNICAM_SD_NUM_PADS		(1 + UNICAM_SD_PAD_SOURCE_METADATA)
> 
> How about an enum then ?

OK.

> > +
> > +enum unicam_node_type {
> > +	UNICAM_IMAGE_NODE,
> > +	UNICAM_METADATA_NODE,
> > +	UNICAM_MAX_NODES
> > +};
> > +
> > +/*
> > + * struct unicam_format_info - Unicam media bus format information
> > + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> > + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> > + * out to 16bpp. 0 if n/a.
> > + * @code: V4L2 media bus format code.
> > + * @depth: Bits per pixel as delivered from the source.
> > + * @csi_dt: CSI data type.
> > + * @metadata_fmt: This format only applies to the metadata pad.
> > + */
> > +struct unicam_format_info {
> > +	u32	fourcc;
> > +	u32	unpacked_fourcc;
> > +	u32	code;
> > +	u8	depth;
> > +	u8	csi_dt;
> > +	bool	metadata_fmt;
> > +};
> > +
> > +struct unicam_buffer {
> > +	struct vb2_v4l2_buffer vb;
> > +	struct list_head list;
> > +	dma_addr_t dma_addr;
> > +	unsigned int size;
> > +};
> > +
> > +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> > +{
> > +	return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> > +}
> > +
> > +struct unicam_node {
> > +	bool registered;
> > +	bool streaming;
> > +	unsigned int id;
> > +
> > +	/* Pointer to the current v4l2_buffer */
> > +	struct unicam_buffer *cur_frm;
> > +	/* Pointer to the next v4l2_buffer */
> > +	struct unicam_buffer *next_frm;
> > +	/* video capture */
> > +	const struct unicam_format_info *fmtinfo;
> > +	/* Used to store current pixel format */
> > +	struct v4l2_format fmt;
> > +	/* Buffer queue used in video-buf */
> > +	struct vb2_queue buffer_queue;
> > +	/* Queue of filled frames */
> > +	struct list_head dma_queue;
> > +	/* IRQ lock for DMA queue */
> > +	spinlock_t dma_queue_lock;
> > +	/* lock used to access this structure */
> > +	struct mutex lock;
> > +	/* Identifies video device for this channel */
> > +	struct video_device video_dev;
> > +	/* Pointer to the parent handle */
> > +	struct unicam_device *dev;
> > +	struct media_pad pad;
> > +	/*
> > +	 * Dummy buffer intended to be used by unicam
> > +	 * if we have no other queued buffers to swap to.
> > +	 */
> > +	struct unicam_buffer dummy_buf;
> > +	void *dummy_buf_cpu_addr;
> > +};
> > +
> > +struct unicam_device {
> > +	struct kref kref;
> > +
> > +	/* peripheral base address */
> > +	void __iomem *base;
> > +	/* clock gating base address */
> > +	void __iomem *clk_gate_base;
> 
> Is the clock gating part of unicam or should this be expressed as a
> clock provide and be referenced in DT through a phandle ?

No idea :-) Dave, Naush ?

> > +	/* lp clock handle */
> > +	struct clk *clock;
> > +	/* vpu clock handle */
> > +	struct clk *vpu_clock;
> > +	/* V4l2 device */
> > +	struct v4l2_device v4l2_dev;
> > +	struct media_device mdev;
> > +
> > +	/* parent device */
> > +	struct device *dev;
> > +	/* subdevice async Notifier */
> 
> s/Notifier/notifier
> 
> > +	struct v4l2_async_notifier notifier;
> > +	unsigned int sequence;
> > +
> > +	/* Sensor node */
> > +	struct {
> > +		struct v4l2_subdev *subdev;
> > +		struct media_pad *pad;
> > +	} sensor;
> > +
> > +	/* Internal subdev */
> > +	struct {
> > +		struct v4l2_subdev sd;
> > +		struct media_pad pads[UNICAM_SD_NUM_PADS];
> > +		bool streaming;
> > +	} subdev;
> > +
> > +	enum v4l2_mbus_type bus_type;
> > +	/*
> > +	 * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> > +	 * bus.mipi_csi1.strobe for CCP2.
> > +	 */
> > +	unsigned int bus_flags;
> > +	unsigned int max_data_lanes;
> > +	unsigned int active_data_lanes;
> > +
> > +	struct media_pipeline pipe;
> > +
> > +	struct unicam_node node[UNICAM_MAX_NODES];
> > +};
> > +
> > +static inline struct unicam_device *
> > +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> > +{
> > +	return container_of(notifier, struct unicam_device, notifier);
> > +}
> > +
> > +static inline struct unicam_device *
> 
> I thought using inline is disouraged as the compiler knows what to do

For this kind of wrapper around container_of() the kernel usually has an
explicit inline keyword. I can drop it if needed.

> > +sd_to_unicam_device(struct v4l2_subdev *sd)
> > +{
> > +	return container_of(sd, struct unicam_device, subdev.sd);
> 
> You can also use container_of_const() if you need it

There's no const subdev anywhere.

> > +}
> > +
> > +static void unicam_release(struct kref *kref)
> > +{
> > +	struct unicam_device *unicam =
> > +		container_of(kref, struct unicam_device, kref);
> > +
> > +	if (unicam->mdev.dev)
> > +		media_device_cleanup(&unicam->mdev);
> > +
> > +	kfree(unicam);
> > +}
> > +
> > +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> > +{
> > +	kref_get(&unicam->kref);
> > +	return unicam;
> > +}
> > +
> > +static void unicam_put(struct unicam_device *unicam)
> > +{
> > +	kref_put(&unicam->kref, unicam_release);
> > +}
> > +
> 
> Does this handle a bit more gracefully the pesky lifetime management
> issue in v4l2 ?

That's supposed to be the idea :-)

> > +/* -----------------------------------------------------------------------------
> > + * Misc helper functions
> > + */
> > +
> > +static inline bool unicam_sd_pad_is_source(u32 pad)
> > +{
> > +	/* Camera RX has 1 sink pad, and N source pads */
> > +	return pad != UNICAM_SD_PAD_SINK;
> > +}
> > +
> > +static inline bool is_metadata_node(struct unicam_node *node)
> > +{
> > +	return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> > +}
> > +
> > +static inline bool is_image_node(struct unicam_node *node)
> > +{
> > +	return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> > +}

[snip]

> > +/* -----------------------------------------------------------------------------
> > + * Videobuf2 queue operations
> > + */
> > +
> > +static int unicam_queue_setup(struct vb2_queue *vq,
> > +			      unsigned int *nbuffers,
> > +			      unsigned int *nplanes,
> > +			      unsigned int sizes[],
> > +			      struct device *alloc_devs[])
> > +{
> > +	struct unicam_node *node = vb2_get_drv_priv(vq);
> > +	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > +		 : node->fmt.fmt.meta.buffersize;
> > +
> > +	if (vq->num_buffers + *nbuffers < 3)
> 
> Why 3 ? Are these dummies ?

This may be a remnant of old code. Dave, Naush, any comment ?

> > +		*nbuffers = 3 - vq->num_buffers;
> > +
> > +	if (*nplanes) {
> > +		if (sizes[0] < size) {
> > +			dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> > +				sizes[0], size);
> > +			return -EINVAL;
> > +		}
> > +		size = sizes[0];
> > +	}
> > +
> > +	*nplanes = 1;
> > +	sizes[0] = size;
> > +
> > +	return 0;
> > +}
> > +
> > +static int unicam_buffer_prepare(struct vb2_buffer *vb)
> > +{
> > +	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > +	struct unicam_buffer *buf = to_unicam_buffer(vb);
> > +	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > +		 : node->fmt.fmt.meta.buffersize;
> > +
> > +	if (vb2_plane_size(vb, 0) < size) {
> > +		dev_dbg(node->dev->dev,
> > +			"data will not fit into plane (%lu < %u)\n",
> > +			vb2_plane_size(vb, 0), size);
> > +		return -EINVAL;
> > +	}
> > +
> > +	buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> > +	buf->size = size;
> > +
> > +	vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> > +
> > +	return 0;
> > +}
> > +
> > +static void unicam_return_buffers(struct unicam_node *node,
> > +				  enum vb2_buffer_state state)
> > +{
> > +	struct unicam_buffer *buf, *tmp;
> > +
> > +	list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> > +		list_del(&buf->list);
> > +		vb2_buffer_done(&buf->vb.vb2_buf, state);
> > +	}
> > +
> > +	if (node->cur_frm)
> > +		vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> > +				state);
> > +	if (node->next_frm && node->cur_frm != node->next_frm)
> > +		vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> > +				state);
> > +
> > +	node->cur_frm = NULL;
> > +	node->next_frm = NULL;
> > +}
> > +
> > +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> > +{
> > +	struct unicam_node *node = vb2_get_drv_priv(vq);
> > +	struct unicam_device *unicam = node->dev;
> > +	struct v4l2_subdev_state *state;
> > +	struct unicam_buffer *buf;
> > +	unsigned long flags;
> > +	int ret;
> > +	u32 pad, stream;
> > +	u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +					     : UNICAM_SD_PAD_SOURCE_METADATA;
> > +
> > +	/* Look for the route for the given pad and stream. */
> > +	state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> > +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > +						    remote_pad, 0,
> > +						    &pad, &stream);
> > +	v4l2_subdev_unlock_state(state);
> > +
> > +	if (ret)
> > +		goto err_return_buffers;
> > +
> > +	dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> > +		unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> > +		is_metadata_node(node) ? "metadata" : "image");
> > +
> > +	/* The metadata node can't be started alone. */
> > +	if (is_metadata_node(node)) {
> > +		if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> 
> Does it mean the metadata node has to be started second, or should
> this be made a nop and the metadata node gets started once the image
> node is started too ? I'm fine with the constraint of having the
> metadata node being started second fwiw

I think it would be nice to change this indeed. Dave, Naush, any
objection ?

> > +			dev_err(unicam->dev,
> > +				"Can't start metadata without image\n");
> > +			ret = -EINVAL;
> > +			goto err_return_buffers;
> > +		}
> > +
> > +		spin_lock_irqsave(&node->dma_queue_lock, flags);
> > +		buf = list_first_entry(&node->dma_queue,
> > +				       struct unicam_buffer, list);
> > +		dev_dbg(unicam->dev, "buffer %p\n", buf);
> 
> Is this useful ?

Probably not much. I'll drop it.

> > +		node->cur_frm = buf;
> > +		node->next_frm = buf;
> > +		list_del(&buf->list);
> > +		spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > +
> > +		unicam_start_metadata(unicam, buf);
> > +		node->streaming = true;
> > +		return 0;
> > +	}
> > +
> > +	ret = pm_runtime_resume_and_get(unicam->dev);
> > +	if (ret < 0) {
> > +		dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> > +		goto err_return_buffers;
> > +	}
> > +
> > +	ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> > +	if (ret < 0) {
> > +		dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> 
> Isn't this an err ?

The main cause of failure is a pipeline validation error, triggered by
userspace, hence the debug level.

> > +		goto err_pm_put;
> > +	}
> > +
> > +	spin_lock_irqsave(&node->dma_queue_lock, flags);
> > +	buf = list_first_entry(&node->dma_queue,
> > +			       struct unicam_buffer, list);
> > +	dev_dbg(unicam->dev, "buffer %p\n", buf);
> > +	node->cur_frm = buf;
> > +	node->next_frm = buf;
> > +	list_del(&buf->list);
> > +	spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > +
> > +	unicam_start_rx(unicam, buf);
> > +
> > +	ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> 
> A bit confused by the API here, shouldn't we also do this for embedded
> data ?

Not here, as the two streams go over different pads, but likely above,
as part of the change you proposed regarding stream start on the
metadata device. I'll wait for Dave and Naush to reply, and I'll rework
this function.

> > +	if (ret < 0) {
> > +		dev_err(unicam->dev, "stream on failed in subdev\n");
> > +		goto error_pipeline;
> > +	}
> > +
> > +	node->streaming = true;
> > +
> > +	return 0;
> > +
> > +error_pipeline:
> > +	video_device_pipeline_stop(&node->video_dev);
> > +err_pm_put:
> > +	pm_runtime_put_sync(unicam->dev);
> > +err_return_buffers:
> > +	unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> > +	return ret;
> > +}
> > +
> > +static void unicam_stop_streaming(struct vb2_queue *vq)
> > +{
> > +	struct unicam_node *node = vb2_get_drv_priv(vq);
> > +	struct unicam_device *unicam = node->dev;
> > +	u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +						   : UNICAM_SD_PAD_SOURCE_METADATA;
> > +
> > +	node->streaming = false;
> > +
> > +	v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> > +				    BIT(0));
> > +
> > +	/* We can stream only with the image node. */
> > +	if (is_metadata_node(node)) {
> > +		/*
> > +		 * Allow the hardware to spin in the dummy buffer.
> > +		 * This is only really needed if the embedded data pad is
> > +		 * disabled before the image pad.
> > +		 */
> > +		unicam_wr_dma_addr(node, &node->dummy_buf);
> > +		goto dequeue_buffers;
> > +	}
> > +
> > +	unicam_disable(unicam);
> > +
> > +	video_device_pipeline_stop(&node->video_dev);
> > +	pm_runtime_put(unicam->dev);
> > +
> > +dequeue_buffers:
> > +	/* Clear all queued buffers for the node */
> > +	unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> > +}
> > +
> > +static void unicam_buffer_queue(struct vb2_buffer *vb)
> > +{
> > +	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > +	struct unicam_buffer *buf = to_unicam_buffer(vb);
> > +
> > +	spin_lock_irq(&node->dma_queue_lock);
> > +	list_add_tail(&buf->list, &node->dma_queue);
> > +	spin_unlock_irq(&node->dma_queue_lock);
> > +}
> > +
> > +static const struct vb2_ops unicam_video_qops = {
> > +	.queue_setup		= unicam_queue_setup,
> > +	.wait_prepare		= vb2_ops_wait_prepare,
> > +	.wait_finish		= vb2_ops_wait_finish,
> > +	.buf_prepare		= unicam_buffer_prepare,
> > +	.start_streaming	= unicam_start_streaming,
> > +	.stop_streaming		= unicam_stop_streaming,
> > +	.buf_queue		= unicam_buffer_queue,
> > +};
> > +
> > +/* -----------------------------------------------------------------------------
> > + *  V4L2 video device operations
> > + */
> > +
> > +static int unicam_querycap(struct file *file, void *priv,
> > +			   struct v4l2_capability *cap)
> > +{
> > +	strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> > +	strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> > +
> > +	cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> > +
> > +	return 0;
> > +}
> > +
> > +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> > +			       struct v4l2_fmtdesc *f)
> > +{
> > +	unsigned int index;
> > +	unsigned int i;
> > +
> > +	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> > +		if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> > +			continue;
> > +
> > +		if (index == f->index) {
> > +			f->pixelformat = unicam_image_formats[i].fourcc;
> > +			return 0;
> > +		}
> > +
> > +		index++;
> > +
> > +		if (!unicam_image_formats[i].unpacked_fourcc)
> > +			continue;
> > +
> > +		if (index == f->index) {
> > +			f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> > +			return 0;
> > +		}
> > +
> > +		index++;
> > +	}
> > +
> > +	return -EINVAL;
> > +}
> > +
> > +static int unicam_g_fmt_vid(struct file *file, void *priv,
> > +			    struct v4l2_format *f)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +
> > +	*f = node->fmt;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct unicam_format_info *
> > +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> > +{
> > +	const struct unicam_format_info *fmtinfo;
> > +
> > +	/*
> > +	 * Default to the first format if the requested pixel format code isn't
> > +	 * supported.
> > +	 */
> > +	fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> > +					       UNICAM_SD_PAD_SOURCE_IMAGE);
> > +	if (!fmtinfo) {
> > +		fmtinfo = &unicam_image_formats[0];
> > +		pix->pixelformat = fmtinfo->fourcc;
> > +	}
> > +
> > +	unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> > +
> > +	if (pix->field == V4L2_FIELD_ANY)
> > +		pix->field = V4L2_FIELD_NONE;
> > +
> > +	return fmtinfo;
> > +}
> > +
> > +static int unicam_try_fmt_vid(struct file *file, void *priv,
> > +			      struct v4l2_format *f)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +
> > +	__unicam_try_fmt_vid(node, &f->fmt.pix);
> > +	return 0;
> > +}
> > +
> > +static int unicam_s_fmt_vid(struct file *file, void *priv,
> > +			    struct v4l2_format *f)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +
> > +	if (vb2_is_busy(&node->buffer_queue))
> > +		return -EBUSY;
> > +
> > +	node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> > +	node->fmt = *f;
> > +
> > +	return 0;
> > +}
> > +
> > +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> > +				struct v4l2_fmtdesc *f)
> > +{
> > +	unsigned int i, index;
> > +
> > +	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> > +		if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
> 
> Do we want to allow mbus_code filtering for metadata ? There's a
> 1-to-1 relationship between mbus codes and pixel formats

Is there a reason not to allow it ? I think it's good for the API to be
consistent. Generally speaking, a CSI-2 receiver could receive
META_CSI2_10 and convert it to the META_8 pixel format. Filtering as a
concept thus make sense I think.

> > +			continue;
> > +		if (!unicam_meta_formats[i].metadata_fmt)
> > +			continue;
> 
> How can this be false if we're iterating on unicam_meta_formats[] ?

True. I'll drop the metadata_fmt field.

> > +
> > +		if (index == f->index) {
> > +			f->pixelformat = unicam_meta_formats[i].fourcc;
> > +			f->type = V4L2_BUF_TYPE_META_CAPTURE;
> > +			return 0;
> > +		}
> > +		index++;
> > +	}
> > +
> > +	return -EINVAL;
> > +}
> > +
> > +static int unicam_g_fmt_meta(struct file *file, void *priv,
> > +			     struct v4l2_format *f)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +
> > +	f->fmt.meta = node->fmt.fmt.meta;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct unicam_format_info *
> > +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> > +{
> > +	const struct unicam_format_info *fmtinfo;
> > +
> > +	/*
> > +	 * Default to the first format if the requested pixel format code isn't
> > +	 * supported.
> > +	 */
> > +	fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> > +					       UNICAM_SD_PAD_SOURCE_METADATA);
> > +	if (!fmtinfo) {
> > +		fmtinfo = &unicam_meta_formats[0];
> > +		meta->dataformat = fmtinfo->fourcc;
> > +	}
> > +
> > +	unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> > +
> > +	return fmtinfo;
> > +}
> > +
> > +static int unicam_try_fmt_meta(struct file *file, void *priv,
> > +			       struct v4l2_format *f)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +
> > +	__unicam_try_fmt_vid(node, &f->fmt.pix);
> > +	return 0;
> > +}
> > +
> > +static int unicam_s_fmt_meta(struct file *file, void *priv,
> > +			     struct v4l2_format *f)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +
> > +	if (vb2_is_busy(&node->buffer_queue))
> > +		return -EBUSY;
> > +
> > +	node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> > +	node->fmt = *f;
> > +
> > +	return 0;
> > +}
> > +
> > +static int unicam_enum_framesizes(struct file *file, void *fh,
> > +				  struct v4l2_frmsizeenum *fsize)
> > +{
> > +	struct unicam_node *node = video_drvdata(file);
> > +	int ret = -EINVAL;
> > +
> > +	if (fsize->index > 0)
> > +		return ret;
> > +
> > +	if (is_image_node(node)) {
> > +		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > +						  UNICAM_SD_PAD_SOURCE_IMAGE))
> > +			return ret;
> > +
> > +		fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> > +		fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> > +		fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> > +		fsize->stepwise.step_width = 1;
> > +		fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> > +		fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> > +		fsize->stepwise.step_height = 1;
> > +	} else {
> > +		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > +						  UNICAM_SD_PAD_SOURCE_METADATA))
> > +			return ret;
> > +
>
> Isn't this V4L2_FRMSIZE_TYPE_STEPWISE as well ?

Indeed, I'll fix that.

> > +		fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> > +		fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> > +		fsize->stepwise.step_width = 1;
> > +		fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> > +		fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> > +		fsize->stepwise.step_height = 1;
> > +	}
> > +
> > +	return 0;
> > +}

[snip]

Dave Stevenson March 5, 2024, 2:15 p.m. UTC | #3

Hi Laurent and Jacopo.

I'd started this reply before Laurent's follow up - I'll respond to
that in a moment.

On Mon, 4 Mar 2024 at 17:12, Jacopo Mondi <[e-mail]> wrote:
>
> Hi Laurent
>
> On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > From: Dave Stevenson <[e-mail]>
> >
> > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > It is represented as two video device nodes: unicam-image and
> > unicam-embedded which are connected to an internal subdev (named
> > unicam-subdev) in order to manage streams routing.
> >
> > Signed-off-by: Dave Stevenson <[e-mail]>
> > Co-developed-by: Naushir Patuck <[e-mail]>
> > Signed-off-by: Naushir Patuck <[e-mail]>
> > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > Co-developed-by: Laurent Pinchart <[e-mail]>
> > Signed-off-by: Laurent Pinchart <[e-mail]>
> > ---
> > Changes since v5:
> >
> > - Move to drivers/media/platform/broadcom/
> > - Port to the upstream V4L2 streams API
> > - Rebase on latest metadata API proposal
> > - Add missing error message
> > - Drop unneeded documentation block for unicam_isr()
> > - Drop unneeded dev_dbg() and dev_err() messages
> > - Drop unneeded streams_mask and fmt checks
> > - Drop unused unicam_sd_pad_is_sink()
> > - Drop unneeded includes
> > - Drop v4l2_ctrl_subscribe_event() call
> > - Use pm_runtime_resume_and_get()
> > - Indentation and line wrap fixes
> > - Let the framework set bus_info
> > - Use v4l2_fwnode_endpoint_parse()
> > - Fix media device cleanup
> > - Drop lane reordering checks
> > - Fix subdev state locking
> > - Drop extra debug messages
> > - Move clock handling to runtime PM handlers
> > - Reorder functions
> > - Rename init functions for more clarity
> > - Initialize runtime PM earlier
> > - Clarify error messages
> > - Simplify subdev init with local variable
> > - Fix subdev cleanup
> > - Fix typos and indentation
> > - Don't initialize local variables needlessly
> > - Simplify num lanes check
> > - Fix metadata handling in subdev set_fmt
> > - Drop manual fallback to .s_stream()
> > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > - Simplify unicam_set_default_format()
> > - Fix default format settings
> > - Add busy check in unicam_s_fmt_meta()
> > - Add missing \n at end of format strings
> > - Fix metadata handling in subdev set_fmt
> > - Fix locking when starting streaming
> > - Return buffers from start streaming fails
> > - Fix format validation for metadata node
> > - Use video_device_pipeline_{start,stop}() helpers
> > - Simplify format enumeration
> > - Drop unset variable
> > - Update MAINTAINERS entry
> > - Update to the upstream v4l2_async_nf API
> > - Update to the latest subdev routing API
> > - Update to the latest subdev state API
> > - Move from subdev .init_cfg() to .init_state()
> > - Update to the latest videobuf2 API
> > - Fix v4l2_subdev_enable_streams() error check
> > - Use correct pad for the connected subdev
> > - Return buffers to vb2 when start streaming fails
> > - Improve debugging in start streaming handler
> > - Simplify DMA address management
> > - Drop comment about bcm2835-camera driver
> > - Clarify comments that explain min/max sizes
> > - Pass v4l2_pix_format to unicam_try_fmt()
> > - Drop unneeded local variables
> > - Rename image-related constants and functions
> > - Turn unicam_fmt.metadata_fmt into bool
> > - Rename unicam_fmt to unicam_format_info
> > - Rename unicam_format_info variables to fmtinfo
> > - Rename unicam_node.v_fmt to fmt
> > - Add metadata formats for RAW10, RAW12 and RAW14
> > - Make metadata formats line-based
> > - Validate format on metadata video device
> > - Add Co-devlopped-by tags
> >
> > Changes since v3:
> >
> > - Add the vendor prefix for DT name
> > - Use the reg-names in DT parsing
> > - Remove MAINTAINERS entry
> >
> > Changes since v2:
> >
> > - Change code organization
> > - Remove unused variables
> > - Correct the fmt_meta functions
> > - Rewrite the start/stop streaming
> >   - You can now start the image node alone, but not the metadata one
> >   - The buffers are allocated per-node
> >   - only the required stream is started, if the route exists and is
> >     enabled
> > - Prefix the macros with UNICAM_ to not have too generic names
> > - Drop colorspace support
> >
> > Changes since v1:
> >
> > - Replace the unicam_{info,debug,error} macros with dev_*()
> > ---
> >  MAINTAINERS                                   |    1 +
> >  drivers/media/platform/Kconfig                |    1 +
> >  drivers/media/platform/Makefile               |    1 +
> >  drivers/media/platform/broadcom/Kconfig       |   23 +
> >  drivers/media/platform/broadcom/Makefile      |    3 +
> >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> >  7 files changed, 2891 insertions(+)
> >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> >  create mode 100644 drivers/media/platform/broadcom/Makefile
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index e50a59654e6e..cc350729f467 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -4002,6 +4002,7 @@ M:      Raspberry Pi Kernel Maintenance <[e-mail]>
> >  L:   [e-mail]
> >  S:   Maintained
> >  F:   Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > +F:   drivers/media/platform/bcm2835/
> >
> >  BROADCOM BCM47XX MIPS ARCHITECTURE
> >  M:   Hauke Mehrtens <[e-mail]>
> > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > index 91e54215de3a..2d79bfc68c15 100644
> > --- a/drivers/media/platform/Kconfig
> > +++ b/drivers/media/platform/Kconfig
> > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> >  source "drivers/media/platform/amphion/Kconfig"
> >  source "drivers/media/platform/aspeed/Kconfig"
> >  source "drivers/media/platform/atmel/Kconfig"
> > +source "drivers/media/platform/broadcom/Kconfig"
> >  source "drivers/media/platform/cadence/Kconfig"
> >  source "drivers/media/platform/chips-media/Kconfig"
> >  source "drivers/media/platform/intel/Kconfig"
> > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > index 3296ec1ebe16..da17301f7439 100644
> > --- a/drivers/media/platform/Makefile
> > +++ b/drivers/media/platform/Makefile
> > @@ -10,6 +10,7 @@ obj-y += amlogic/
> >  obj-y += amphion/
> >  obj-y += aspeed/
> >  obj-y += atmel/
> > +obj-y += broadcom/
> >  obj-y += cadence/
> >  obj-y += chips-media/
> >  obj-y += intel/
> > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > new file mode 100644
> > index 000000000000..cc2c9afcc948
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/Kconfig
> > @@ -0,0 +1,23 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +config VIDEO_BCM2835_UNICAM
> > +     tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > +     depends on ARCH_BCM2835 || COMPILE_TEST
> > +     depends on PM
> > +     depends on VIDEO_DEV
> > +     select MEDIA_CONTROLLER
> > +     select V4L2_FWNODE
> > +     select VIDEO_V4L2_SUBDEV_API
> > +     select VIDEOBUF2_DMA_CONTIG
> > +     help
> > +       Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > +       This is a V4L2 driver that controls the CSI-2 receiver directly,
> > +       independently from the VC4 firmware.
> > +
> > +       This driver is mutually exclusive with the use of bcm2835-camera. The
> > +       firmware will disable all access to the peripheral from within the
> > +       firmware if it finds a DT node using it, and bcm2835-camera will
> > +       therefore fail to probe.
> > +
> > +       To compile this driver as a module, choose M here. The module will be
> > +       called bcm2835-unicam.
> > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > new file mode 100644
> > index 000000000000..03d2045aba2e
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/Makefile
> > @@ -0,0 +1,3 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > new file mode 100644
> > index 000000000000..84775fd2fac5
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > @@ -0,0 +1,255 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +
> > +/*
> > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> > + * Dave Stevenson <[e-mail]>
> > + */
> > +
> > +#ifndef VC4_REGS_UNICAM_H
> > +#define VC4_REGS_UNICAM_H
> > +
> > +#include <linux/bits.h>
> > +
> > +/*
> > + * The following values are taken from files found within the code drop
> > + * made by Broadcom for the BCM21553 Graphics Driver, predominantly in
> > + * brcm_usrlib/dag/vmcsx/vcinclude/hardware_vc4.h.
> > + * They have been modified to be only the register offset.
> > + */
> > +#define UNICAM_CTRL          0x000
> > +#define UNICAM_STA           0x004
> > +#define UNICAM_ANA           0x008
> > +#define UNICAM_PRI           0x00c
> > +#define UNICAM_CLK           0x010
> > +#define UNICAM_CLT           0x014
> > +#define UNICAM_DAT0          0x018
> > +#define UNICAM_DAT1          0x01c
> > +#define UNICAM_DAT2          0x020
> > +#define UNICAM_DAT3          0x024
> > +#define UNICAM_DLT           0x028
> > +#define UNICAM_CMP0          0x02c
> > +#define UNICAM_CMP1          0x030
> > +#define UNICAM_CAP0          0x034
> > +#define UNICAM_CAP1          0x038
> > +#define UNICAM_ICTL          0x100
> > +#define UNICAM_ISTA          0x104
> > +#define UNICAM_IDI0          0x108
> > +#define UNICAM_IPIPE         0x10c
> > +#define UNICAM_IBSA0         0x110
> > +#define UNICAM_IBEA0         0x114
> > +#define UNICAM_IBLS          0x118
> > +#define UNICAM_IBWP          0x11c
> > +#define UNICAM_IHWIN         0x120
> > +#define UNICAM_IHSTA         0x124
> > +#define UNICAM_IVWIN         0x128
> > +#define UNICAM_IVSTA         0x12c
> > +#define UNICAM_ICC           0x130
> > +#define UNICAM_ICS           0x134
> > +#define UNICAM_IDC           0x138
> > +#define UNICAM_IDPO          0x13c
> > +#define UNICAM_IDCA          0x140
> > +#define UNICAM_IDCD          0x144
> > +#define UNICAM_IDS           0x148
> > +#define UNICAM_DCS           0x200
> > +#define UNICAM_DBSA0         0x204
> > +#define UNICAM_DBEA0         0x208
> > +#define UNICAM_DBWP          0x20c
> > +#define UNICAM_DBCTL         0x300
> > +#define UNICAM_IBSA1         0x304
> > +#define UNICAM_IBEA1         0x308
> > +#define UNICAM_IDI1          0x30c
> > +#define UNICAM_DBSA1         0x310
> > +#define UNICAM_DBEA1         0x314
> > +#define UNICAM_MISC          0x400
> > +
> > +/*
> > + * The following bitmasks are from the kernel released by Broadcom
> > + * for Android - https://android.googlesource.com/kernel/bcm/
> > + * The Rhea, Hawaii, and Java chips all contain the same VideoCore4
> > + * Unicam block as BCM2835, as defined in eg
> > + * arch/arm/mach-rhea/include/mach/rdb_A0/brcm_rdb_cam.h and similar.
> > + * Values reworked to use the kernel BIT and GENMASK macros.
> > + *
> > + * Some of the bit mnenomics have been amended to match the datasheet.
> > + */
> > +/* UNICAM_CTRL Register */
> > +#define UNICAM_CPE           BIT(0)
> > +#define UNICAM_MEM           BIT(1)
> > +#define UNICAM_CPR           BIT(2)
> > +#define UNICAM_CPM_MASK              GENMASK(3, 3)
> > +#define UNICAM_CPM_CSI2              0
> > +#define UNICAM_CPM_CCP2              1
> > +#define UNICAM_SOE           BIT(4)
> > +#define UNICAM_DCM_MASK              GENMASK(5, 5)
> > +#define UNICAM_DCM_STROBE    0
> > +#define UNICAM_DCM_DATA              1
> > +#define UNICAM_SLS           BIT(6)
> > +#define UNICAM_PFT_MASK              GENMASK(11, 8)
> > +#define UNICAM_OET_MASK              GENMASK(20, 12)
> > +
> > +/* UNICAM_STA Register */
> > +#define UNICAM_SYN           BIT(0)
> > +#define UNICAM_CS            BIT(1)
> > +#define UNICAM_SBE           BIT(2)
> > +#define UNICAM_PBE           BIT(3)
> > +#define UNICAM_HOE           BIT(4)
> > +#define UNICAM_PLE           BIT(5)
> > +#define UNICAM_SSC           BIT(6)
> > +#define UNICAM_CRCE          BIT(7)
> > +#define UNICAM_OES           BIT(8)
> > +#define UNICAM_IFO           BIT(9)
> > +#define UNICAM_OFO           BIT(10)
> > +#define UNICAM_BFO           BIT(11)
> > +#define UNICAM_DL            BIT(12)
> > +#define UNICAM_PS            BIT(13)
> > +#define UNICAM_IS            BIT(14)
> > +#define UNICAM_PI0           BIT(15)
> > +#define UNICAM_PI1           BIT(16)
> > +#define UNICAM_FSI_S         BIT(17)
> > +#define UNICAM_FEI_S         BIT(18)
> > +#define UNICAM_LCI_S         BIT(19)
> > +#define UNICAM_BUF0_RDY              BIT(20)
> > +#define UNICAM_BUF0_NO               BIT(21)
> > +#define UNICAM_BUF1_RDY              BIT(22)
> > +#define UNICAM_BUF1_NO               BIT(23)
> > +#define UNICAM_DI            BIT(24)
> > +
> > +#define UNICAM_STA_MASK_ALL \
> > +             (UNICAM_DL | \
> > +             UNICAM_SBE | \
> > +             UNICAM_PBE | \
> > +             UNICAM_HOE | \
> > +             UNICAM_PLE | \
> > +             UNICAM_SSC | \
> > +             UNICAM_CRCE | \
> > +             UNICAM_IFO | \
> > +             UNICAM_OFO | \
> > +             UNICAM_PS | \
> > +             UNICAM_PI0 | \
> > +             UNICAM_PI1)
> > +
> > +/* UNICAM_ANA Register */
> > +#define UNICAM_APD           BIT(0)
> > +#define UNICAM_BPD           BIT(1)
> > +#define UNICAM_AR            BIT(2)
> > +#define UNICAM_DDL           BIT(3)
> > +#define UNICAM_CTATADJ_MASK  GENMASK(7, 4)
> > +#define UNICAM_PTATADJ_MASK  GENMASK(11, 8)
> > +
> > +/* UNICAM_PRI Register */
> > +#define UNICAM_PE            BIT(0)
> > +#define UNICAM_PT_MASK               GENMASK(2, 1)
> > +#define UNICAM_NP_MASK               GENMASK(7, 4)
> > +#define UNICAM_PP_MASK               GENMASK(11, 8)
> > +#define UNICAM_BS_MASK               GENMASK(15, 12)
> > +#define UNICAM_BL_MASK               GENMASK(17, 16)
> > +
> > +/* UNICAM_CLK Register */
> > +#define UNICAM_CLE           BIT(0)
> > +#define UNICAM_CLPD          BIT(1)
> > +#define UNICAM_CLLPE         BIT(2)
> > +#define UNICAM_CLHSE         BIT(3)
> > +#define UNICAM_CLTRE         BIT(4)
> > +#define UNICAM_CLAC_MASK     GENMASK(8, 5)
> > +#define UNICAM_CLSTE         BIT(29)
> > +
> > +/* UNICAM_CLT Register */
> > +#define UNICAM_CLT1_MASK     GENMASK(7, 0)
> > +#define UNICAM_CLT2_MASK     GENMASK(15, 8)
> > +
> > +/* UNICAM_DATn Registers */
> > +#define UNICAM_DLE           BIT(0)
> > +#define UNICAM_DLPD          BIT(1)
> > +#define UNICAM_DLLPE         BIT(2)
> > +#define UNICAM_DLHSE         BIT(3)
> > +#define UNICAM_DLTRE         BIT(4)
> > +#define UNICAM_DLSM          BIT(5)
> > +#define UNICAM_DLFO          BIT(28)
> > +#define UNICAM_DLSTE         BIT(29)
> > +
> > +#define UNICAM_DAT_MASK_ALL  (UNICAM_DLSTE | UNICAM_DLFO)
> > +
> > +/* UNICAM_DLT Register */
> > +#define UNICAM_DLT1_MASK     GENMASK(7, 0)
> > +#define UNICAM_DLT2_MASK     GENMASK(15, 8)
> > +#define UNICAM_DLT3_MASK     GENMASK(23, 16)
> > +
> > +/* UNICAM_ICTL Register */
> > +#define UNICAM_FSIE          BIT(0)
> > +#define UNICAM_FEIE          BIT(1)
> > +#define UNICAM_IBOB          BIT(2)
> > +#define UNICAM_FCM           BIT(3)
> > +#define UNICAM_TFC           BIT(4)
> > +#define UNICAM_LIP_MASK              GENMASK(6, 5)
> > +#define UNICAM_LCIE_MASK     GENMASK(28, 16)
> > +
> > +/* UNICAM_IDI0/1 Register */
> > +#define UNICAM_ID0_MASK              GENMASK(7, 0)
> > +#define UNICAM_ID1_MASK              GENMASK(15, 8)
> > +#define UNICAM_ID2_MASK              GENMASK(23, 16)
> > +#define UNICAM_ID3_MASK              GENMASK(31, 24)
> > +
> > +/* UNICAM_ISTA Register */
> > +#define UNICAM_FSI           BIT(0)
> > +#define UNICAM_FEI           BIT(1)
> > +#define UNICAM_LCI           BIT(2)
> > +
> > +#define UNICAM_ISTA_MASK_ALL (UNICAM_FSI | UNICAM_FEI | UNICAM_LCI)
> > +
> > +/* UNICAM_IPIPE Register */
> > +#define UNICAM_PUM_MASK              GENMASK(2, 0)
> > +/* Unpacking modes */
> > +#define UNICAM_PUM_NONE              0
> > +#define UNICAM_PUM_UNPACK6   1
> > +#define UNICAM_PUM_UNPACK7   2
> > +#define UNICAM_PUM_UNPACK8   3
> > +#define UNICAM_PUM_UNPACK10  4
> > +#define UNICAM_PUM_UNPACK12  5
> > +#define UNICAM_PUM_UNPACK14  6
> > +#define UNICAM_PUM_UNPACK16  7
> > +#define UNICAM_DDM_MASK              GENMASK(6, 3)
> > +#define UNICAM_PPM_MASK              GENMASK(9, 7)
> > +/* Packing modes */
> > +#define UNICAM_PPM_NONE              0
> > +#define UNICAM_PPM_PACK8     1
> > +#define UNICAM_PPM_PACK10    2
> > +#define UNICAM_PPM_PACK12    3
> > +#define UNICAM_PPM_PACK14    4
> > +#define UNICAM_PPM_PACK16    5
> > +#define UNICAM_DEM_MASK              GENMASK(11, 10)
> > +#define UNICAM_DEBL_MASK     GENMASK(14, 12)
> > +#define UNICAM_ICM_MASK              GENMASK(16, 15)
> > +#define UNICAM_IDM_MASK              GENMASK(17, 17)
> > +
> > +/* UNICAM_ICC Register */
> > +#define UNICAM_ICFL_MASK     GENMASK(4, 0)
> > +#define UNICAM_ICFH_MASK     GENMASK(9, 5)
> > +#define UNICAM_ICST_MASK     GENMASK(12, 10)
> > +#define UNICAM_ICLT_MASK     GENMASK(15, 13)
> > +#define UNICAM_ICLL_MASK     GENMASK(31, 16)
> > +
> > +/* UNICAM_DCS Register */
> > +#define UNICAM_DIE           BIT(0)
> > +#define UNICAM_DIM           BIT(1)
> > +#define UNICAM_DBOB          BIT(3)
> > +#define UNICAM_FDE           BIT(4)
> > +#define UNICAM_LDP           BIT(5)
> > +#define UNICAM_EDL_MASK              GENMASK(15, 8)
> > +
> > +/* UNICAM_DBCTL Register */
> > +#define UNICAM_DBEN          BIT(0)
> > +#define UNICAM_BUF0_IE               BIT(1)
> > +#define UNICAM_BUF1_IE               BIT(2)
> > +
> > +/* UNICAM_CMP[0,1] register */
> > +#define UNICAM_PCE           BIT(31)
> > +#define UNICAM_GI            BIT(9)
> > +#define UNICAM_CPH           BIT(8)
> > +#define UNICAM_PCVC_MASK     GENMASK(7, 6)
> > +#define UNICAM_PCDT_MASK     GENMASK(5, 0)
> > +
> > +/* UNICAM_MISC register */
> > +#define UNICAM_FL0           BIT(6)
> > +#define UNICAM_FL1           BIT(9)
> > +
> > +#endif
> > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > new file mode 100644
> > index 000000000000..716c89b8a217
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > @@ -0,0 +1,2607 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * BCM283x / BCM271x Unicam Capture Driver
> > + *
> > + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> > + *
> > + * Dave Stevenson <[e-mail]>
> > + *
> > + * Based on TI am437x driver by
> > + *   Benoit Parrot <[e-mail]>
> > + *   Lad, Prabhakar <[e-mail]>
> > + *
> > + * and TI CAL camera interface driver by
> > + *    Benoit Parrot <[e-mail]>
> > + *
> > + *
> > + * There are two camera drivers in the kernel for BCM283x - this one and
> > + * bcm2835-camera (currently in staging).
> > + *
> > + * This driver directly controls the Unicam peripheral - there is no
> > + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> > + * and writes it into SDRAM. The only potential processing options are to
> > + * repack Bayer data into an alternate format, and applying windowing. The
> > + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> > + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> > + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> > + * where the relevant formats are defined, and will automatically configure the
> > + * repacking as required. Support for windowing may be added later.
>
> Does this last paragraph applies ? I see all the supported packed raw
> format having an 'unpacked_fourcc' associated (all but the 8 bit ones
> ofc)

The penultimate sentence ("The driver will add both formats where the
relevant formats are defined") can be dropped as you've dropped the
video-node centric mode of operation, therefore all formats (whether
packed or unpacked) are always advertised.

The rest of the paragraph still applies - if you request a
V4L2_PIX_FMT_SxxxxBB (not packed) format, then it the incoming data
will be unpacked for you.

> > + *
> > + * It should be possible to connect this driver to any sensor with a suitable
> > + * output interface and V4L2 subdevice driver.
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/device.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/err.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/slab.h>
> > +#include <linux/videodev2.h>
> > +
> > +#include <media/v4l2-async.h>
> > +#include <media/v4l2-common.h>
> > +#include <media/v4l2-dev.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/v4l2-ioctl.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-mc.h>
> > +#include <media/videobuf2-dma-contig.h>
> > +
> > +#include "bcm2835-unicam-regs.h"
> > +
> > +#define UNICAM_MODULE_NAME           "unicam"
> > +
> > +/*
> > + * Unicam must request a minimum of 250Mhz from the VPU clock.
> > + * Otherwise the input FIFOs overrun and cause image corruption.
> > + */
> > +#define UNICAM_MIN_VPU_CLOCK_RATE    (250 * 1000 * 1000)
>
> Shouldn't this be set in DT ?
>
> > +
> > +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> > +#define UNICAM_DMA_BPL_ALIGNMENT     16
> > +
> > +/*
> > + * The image stride is stored in a 16 bit register, and needs to be aligned to
> > + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> > + * constraint on its input, set the image stride alignment to 32 bytes here as
> > + * well to avoid incompatible configurations.
> > + */
> > +#define UNICAM_IMAGE_BPL_ALIGNMENT   32
> > +#define UNICAM_IMAGE_MAX_BPL         ((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
> > +
> > +/*
> > + * Max width is therefore determined by the max stride divided by the number of
> > + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> > + * so adopt a square image for want of anything better.
> > + */
> > +#define UNICAM_IMAGE_MIN_WIDTH               16
> > +#define UNICAM_IMAGE_MIN_HEIGHT              16
> > +#define UNICAM_IMAGE_MAX_WIDTH               (UNICAM_IMAGE_MAX_BPL / 4)
> > +#define UNICAM_IMAGE_MAX_HEIGHT              UNICAM_IMAGE_MAX_WIDTH
> > +
> > +/*
> > + * There's no intrinsic limits on the width and height for embedded dat. Use
> > + * the same maximum values as for the image, to avoid overflows in the image
> > + * size computation.
> > + */
> > +#define UNICAM_META_MIN_WIDTH                1
> > +#define UNICAM_META_MIN_HEIGHT               1
> > +#define UNICAM_META_MAX_WIDTH                UNICAM_IMAGE_MAX_WIDTH
> > +#define UNICAM_META_MAX_HEIGHT               UNICAM_IMAGE_MAX_HEIGHT
> > +
> > +/*
> > + * Size of the dummy buffer. Can be any size really, but the DMA
> > + * allocation works in units of page sizes.
> > + */
> > +#define UNICAM_DUMMY_BUF_SIZE                PAGE_SIZE
> > +
> > +#define UNICAM_SD_PAD_SINK           0
> > +#define UNICAM_SD_PAD_SOURCE_IMAGE   1
> > +#define UNICAM_SD_PAD_SOURCE_METADATA        2
> > +#define UNICAM_SD_NUM_PADS           (1 + UNICAM_SD_PAD_SOURCE_METADATA)
>
> How about an enum then ?
>
> > +
> > +enum unicam_node_type {
> > +     UNICAM_IMAGE_NODE,
> > +     UNICAM_METADATA_NODE,
> > +     UNICAM_MAX_NODES
> > +};
> > +
> > +/*
> > + * struct unicam_format_info - Unicam media bus format information
> > + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> > + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> > + * out to 16bpp. 0 if n/a.
> > + * @code: V4L2 media bus format code.
> > + * @depth: Bits per pixel as delivered from the source.
> > + * @csi_dt: CSI data type.
> > + * @metadata_fmt: This format only applies to the metadata pad.
> > + */
> > +struct unicam_format_info {
> > +     u32     fourcc;
> > +     u32     unpacked_fourcc;
> > +     u32     code;
> > +     u8      depth;
> > +     u8      csi_dt;
> > +     bool    metadata_fmt;
> > +};
> > +
> > +struct unicam_buffer {
> > +     struct vb2_v4l2_buffer vb;
> > +     struct list_head list;
> > +     dma_addr_t dma_addr;
> > +     unsigned int size;
> > +};
> > +
> > +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> > +{
> > +     return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> > +}
> > +
> > +struct unicam_node {
> > +     bool registered;
> > +     bool streaming;
> > +     unsigned int id;
> > +
> > +     /* Pointer to the current v4l2_buffer */
> > +     struct unicam_buffer *cur_frm;
> > +     /* Pointer to the next v4l2_buffer */
> > +     struct unicam_buffer *next_frm;
> > +     /* video capture */
> > +     const struct unicam_format_info *fmtinfo;
> > +     /* Used to store current pixel format */
> > +     struct v4l2_format fmt;
> > +     /* Buffer queue used in video-buf */
> > +     struct vb2_queue buffer_queue;
> > +     /* Queue of filled frames */
> > +     struct list_head dma_queue;
> > +     /* IRQ lock for DMA queue */
> > +     spinlock_t dma_queue_lock;
> > +     /* lock used to access this structure */
> > +     struct mutex lock;
> > +     /* Identifies video device for this channel */
> > +     struct video_device video_dev;
> > +     /* Pointer to the parent handle */
> > +     struct unicam_device *dev;
> > +     struct media_pad pad;
> > +     /*
> > +      * Dummy buffer intended to be used by unicam
> > +      * if we have no other queued buffers to swap to.
> > +      */
> > +     struct unicam_buffer dummy_buf;
> > +     void *dummy_buf_cpu_addr;
> > +};
> > +
> > +struct unicam_device {
> > +     struct kref kref;
> > +
> > +     /* peripheral base address */
> > +     void __iomem *base;
> > +     /* clock gating base address */
> > +     void __iomem *clk_gate_base;
>
> Is the clock gating part of unicam or should this be expressed as a
> clock provide and be referenced in DT through a phandle ?

Covered in previous reviews and accepted as part of unicam.
https://patchwork.kernel.org/project/linux-media/patch/fae3d2[e-mail]/

> > +     /* lp clock handle */
> > +     struct clk *clock;
> > +     /* vpu clock handle */
> > +     struct clk *vpu_clock;
> > +     /* V4l2 device */
> > +     struct v4l2_device v4l2_dev;
> > +     struct media_device mdev;
> > +
> > +     /* parent device */
> > +     struct device *dev;
> > +     /* subdevice async Notifier */
>
> s/Notifier/notifier
>
> > +     struct v4l2_async_notifier notifier;
> > +     unsigned int sequence;
> > +
> > +     /* Sensor node */
> > +     struct {
> > +             struct v4l2_subdev *subdev;
> > +             struct media_pad *pad;
> > +     } sensor;
> > +
> > +     /* Internal subdev */
> > +     struct {
> > +             struct v4l2_subdev sd;
> > +             struct media_pad pads[UNICAM_SD_NUM_PADS];
> > +             bool streaming;
> > +     } subdev;
> > +
> > +     enum v4l2_mbus_type bus_type;
> > +     /*
> > +      * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> > +      * bus.mipi_csi1.strobe for CCP2.
> > +      */
> > +     unsigned int bus_flags;
> > +     unsigned int max_data_lanes;
> > +     unsigned int active_data_lanes;
> > +
> > +     struct media_pipeline pipe;
> > +
> > +     struct unicam_node node[UNICAM_MAX_NODES];
> > +};
> > +
> > +static inline struct unicam_device *
> > +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> > +{
> > +     return container_of(notifier, struct unicam_device, notifier);
> > +}
> > +
> > +static inline struct unicam_device *
>
> I thought using inline is disouraged as the compiler knows what to do
>
> > +sd_to_unicam_device(struct v4l2_subdev *sd)
> > +{
> > +     return container_of(sd, struct unicam_device, subdev.sd);
>
> You can also use container_of_const() if you need it
>
> > +}
> > +
> > +static void unicam_release(struct kref *kref)
> > +{
> > +     struct unicam_device *unicam =
> > +             container_of(kref, struct unicam_device, kref);
> > +
> > +     if (unicam->mdev.dev)
> > +             media_device_cleanup(&unicam->mdev);
> > +
> > +     kfree(unicam);
> > +}
> > +
> > +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> > +{
> > +     kref_get(&unicam->kref);
> > +     return unicam;
> > +}
> > +
> > +static void unicam_put(struct unicam_device *unicam)
> > +{
> > +     kref_put(&unicam->kref, unicam_release);
> > +}
> > +
>
> Does this handle a bit more gracefully the pesky lifetime management
> issue in v4l2 ?
>
> > +/* -----------------------------------------------------------------------------
> > + * Misc helper functions
> > + */
> > +
> > +static inline bool unicam_sd_pad_is_source(u32 pad)
> > +{
> > +     /* Camera RX has 1 sink pad, and N source pads */
> > +     return pad != UNICAM_SD_PAD_SINK;
> > +}
> > +
> > +static inline bool is_metadata_node(struct unicam_node *node)
> > +{
> > +     return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> > +}
> > +
> > +static inline bool is_image_node(struct unicam_node *node)
> > +{
> > +     return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Format data table and helper functions
> > + */
> > +
> > +static const struct v4l2_mbus_framefmt unicam_default_image_format = {
> > +     .width = 640,
> > +     .height = 480,
> > +     .code = MEDIA_BUS_FMT_UYVY8_1X16,
> > +     .field = V4L2_FIELD_NONE,
> > +     .colorspace = V4L2_COLORSPACE_SRGB,
> > +     .ycbcr_enc = V4L2_YCBCR_ENC_601,
> > +     .quantization = V4L2_QUANTIZATION_LIM_RANGE,
> > +     .xfer_func = V4L2_XFER_FUNC_SRGB,
> > +     .flags = 0,
> > +};
> > +
> > +static const struct v4l2_mbus_framefmt unicam_default_meta_format = {
> > +     .width = 640,
> > +     .height = 2,
> > +     .code = MEDIA_BUS_FMT_META_8,
> > +     .field = V4L2_FIELD_NONE,
> > +};
> > +
> > +static const struct unicam_format_info unicam_image_formats[] = {
> > +     /* YUV Formats */
> > +     {
> > +             .fourcc         = V4L2_PIX_FMT_YUYV,
> > +             .code           = MEDIA_BUS_FMT_YUYV8_1X16,
> > +             .depth          = 16,
> > +             .csi_dt         = 0x1e,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_UYVY,
> > +             .code           = MEDIA_BUS_FMT_UYVY8_1X16,
> > +             .depth          = 16,
> > +             .csi_dt         = 0x1e,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_YVYU,
> > +             .code           = MEDIA_BUS_FMT_YVYU8_1X16,
> > +             .depth          = 16,
> > +             .csi_dt         = 0x1e,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_VYUY,
> > +             .code           = MEDIA_BUS_FMT_VYUY8_1X16,
> > +             .depth          = 16,
> > +             .csi_dt         = 0x1e,
> > +     }, {
> > +     /* RGB Formats */
> > +             .fourcc         = V4L2_PIX_FMT_RGB565, /* gggbbbbb rrrrrggg */
> > +             .code           = MEDIA_BUS_FMT_RGB565_1X16,
> > +             .depth          = 16,
> > +             .csi_dt         = 0x22,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_RGB24, /* rgb */
> > +             .code           = MEDIA_BUS_FMT_RGB888_1X24,
> > +             .depth          = 24,
> > +             .csi_dt         = 0x24,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_BGR24, /* bgr */
> > +             .code           = MEDIA_BUS_FMT_BGR888_1X24,
> > +             .depth          = 24,
> > +             .csi_dt         = 0x24,
> > +     }, {
> > +     /* Bayer Formats */
> > +             .fourcc         = V4L2_PIX_FMT_SBGGR8,
> > +             .code           = MEDIA_BUS_FMT_SBGGR8_1X8,
> > +             .depth          = 8,
> > +             .csi_dt         = 0x2a,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGBRG8,
> > +             .code           = MEDIA_BUS_FMT_SGBRG8_1X8,
> > +             .depth          = 8,
> > +             .csi_dt         = 0x2a,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGRBG8,
> > +             .code           = MEDIA_BUS_FMT_SGRBG8_1X8,
> > +             .depth          = 8,
> > +             .csi_dt         = 0x2a,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SRGGB8,
> > +             .code           = MEDIA_BUS_FMT_SRGGB8_1X8,
> > +             .depth          = 8,
> > +             .csi_dt         = 0x2a,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SBGGR10P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SBGGR10,
> > +             .code           = MEDIA_BUS_FMT_SBGGR10_1X10,
> > +             .depth          = 10,
> > +             .csi_dt         = 0x2b,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGBRG10P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SGBRG10,
> > +             .code           = MEDIA_BUS_FMT_SGBRG10_1X10,
> > +             .depth          = 10,
> > +             .csi_dt         = 0x2b,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGRBG10P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SGRBG10,
> > +             .code           = MEDIA_BUS_FMT_SGRBG10_1X10,
> > +             .depth          = 10,
> > +             .csi_dt         = 0x2b,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SRGGB10P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SRGGB10,
> > +             .code           = MEDIA_BUS_FMT_SRGGB10_1X10,
> > +             .depth          = 10,
> > +             .csi_dt         = 0x2b,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SBGGR12P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SBGGR12,
> > +             .code           = MEDIA_BUS_FMT_SBGGR12_1X12,
> > +             .depth          = 12,
> > +             .csi_dt         = 0x2c,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGBRG12P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SGBRG12,
> > +             .code           = MEDIA_BUS_FMT_SGBRG12_1X12,
> > +             .depth          = 12,
> > +             .csi_dt         = 0x2c,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGRBG12P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SGRBG12,
> > +             .code           = MEDIA_BUS_FMT_SGRBG12_1X12,
> > +             .depth          = 12,
> > +             .csi_dt         = 0x2c,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SRGGB12P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SRGGB12,
> > +             .code           = MEDIA_BUS_FMT_SRGGB12_1X12,
> > +             .depth          = 12,
> > +             .csi_dt         = 0x2c,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SBGGR14P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SBGGR14,
> > +             .code           = MEDIA_BUS_FMT_SBGGR14_1X14,
> > +             .depth          = 14,
> > +             .csi_dt         = 0x2d,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGBRG14P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SGBRG14,
> > +             .code           = MEDIA_BUS_FMT_SGBRG14_1X14,
> > +             .depth          = 14,
> > +             .csi_dt         = 0x2d,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SGRBG14P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SGRBG14,
> > +             .code           = MEDIA_BUS_FMT_SGRBG14_1X14,
> > +             .depth          = 14,
> > +             .csi_dt         = 0x2d,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_SRGGB14P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_SRGGB14,
> > +             .code           = MEDIA_BUS_FMT_SRGGB14_1X14,
> > +             .depth          = 14,
> > +             .csi_dt         = 0x2d,
> > +     }, {
> > +     /* 16 bit Bayer formats could be supported. */
> > +
> > +     /* Greyscale formats */
> > +             .fourcc         = V4L2_PIX_FMT_GREY,
> > +             .code           = MEDIA_BUS_FMT_Y8_1X8,
> > +             .depth          = 8,
> > +             .csi_dt         = 0x2a,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_Y10P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_Y10,
> > +             .code           = MEDIA_BUS_FMT_Y10_1X10,
> > +             .depth          = 10,
> > +             .csi_dt         = 0x2b,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_Y12P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_Y12,
> > +             .code           = MEDIA_BUS_FMT_Y12_1X12,
> > +             .depth          = 12,
> > +             .csi_dt         = 0x2c,
> > +     }, {
> > +             .fourcc         = V4L2_PIX_FMT_Y14P,
> > +             .unpacked_fourcc = V4L2_PIX_FMT_Y14,
> > +             .code           = MEDIA_BUS_FMT_Y14_1X14,
> > +             .depth          = 14,
> > +             .csi_dt         = 0x2d,
> > +     },
> > +};
> > +
> > +static const struct unicam_format_info unicam_meta_formats[] = {
> > +     {
> > +             .fourcc         = V4L2_META_FMT_GENERIC_8,
> > +             .code           = MEDIA_BUS_FMT_META_8,
> > +             .depth          = 8,
> > +             .metadata_fmt   = true,
> > +     }, {
> > +             .fourcc         = V4L2_META_FMT_GENERIC_CSI2_10,
> > +             .code           = MEDIA_BUS_FMT_META_10,
> > +             .depth          = 10,
> > +             .metadata_fmt   = true,
> > +     }, {
> > +             .fourcc         = V4L2_META_FMT_GENERIC_CSI2_12,
> > +             .code           = MEDIA_BUS_FMT_META_12,
> > +             .depth          = 12,
> > +             .metadata_fmt   = true,
> > +     }, {
> > +             .fourcc         = V4L2_META_FMT_GENERIC_CSI2_14,
> > +             .code           = MEDIA_BUS_FMT_META_14,
> > +             .depth          = 14,
> > +             .metadata_fmt   = true,
> > +     },
> > +};
> > +
> > +/* Format setup functions */
> > +static const struct unicam_format_info *
> > +unicam_find_format_by_code(u32 code, u32 pad)
> > +{
> > +     const struct unicam_format_info *formats;
> > +     unsigned int num_formats;
> > +     unsigned int i;
> > +
> > +     if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > +             formats = unicam_image_formats;
> > +             num_formats = ARRAY_SIZE(unicam_image_formats);
> > +     } else {
> > +             formats = unicam_meta_formats;
> > +             num_formats = ARRAY_SIZE(unicam_meta_formats);
> > +     }
> > +
> > +     for (i = 0; i < num_formats; i++) {
> > +             if (formats[i].code == code)
> > +                     return &formats[i];
> > +     }
> > +
> > +     return NULL;
> > +}
> > +
> > +static const struct unicam_format_info *
> > +unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
> > +{
> > +     const struct unicam_format_info *formats;
> > +     unsigned int num_formats;
> > +     unsigned int i;
> > +
> > +     if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > +             formats = unicam_image_formats;
> > +             num_formats = ARRAY_SIZE(unicam_image_formats);
> > +     } else {
> > +             formats = unicam_meta_formats;
> > +             num_formats = ARRAY_SIZE(unicam_meta_formats);
> > +     }
> > +
> > +     for (i = 0; i < num_formats; ++i) {
> > +             if (formats[i].fourcc == fourcc)
> > +                     return &formats[i];
> > +     }
> > +
> > +     return NULL;
> > +}
> > +
> > +static void unicam_calc_image_size_bpl(struct unicam_device *unicam,
> > +                                    const struct unicam_format_info *fmtinfo,
> > +                                    struct v4l2_pix_format *pix)
> > +{
> > +     u32 min_bpl;
> > +
> > +     v4l_bound_align_image(&pix->width, UNICAM_IMAGE_MIN_WIDTH,
> > +                           UNICAM_IMAGE_MAX_WIDTH, 2,
> > +                           &pix->height, UNICAM_IMAGE_MIN_HEIGHT,
> > +                           UNICAM_IMAGE_MAX_HEIGHT, 0, 0);
> > +
> > +     /* Unpacking always goes to 16bpp */
> > +     if (pix->pixelformat == fmtinfo->unpacked_fourcc)
> > +             min_bpl = pix->width * 2;
> > +     else
> > +             min_bpl = pix->width * fmtinfo->depth / 8;
> > +     min_bpl = ALIGN(min_bpl, UNICAM_IMAGE_BPL_ALIGNMENT);
> > +
> > +     pix->bytesperline = ALIGN(pix->bytesperline, UNICAM_IMAGE_BPL_ALIGNMENT);
> > +     pix->bytesperline = clamp_t(unsigned int, pix->bytesperline, min_bpl,
> > +                                 UNICAM_IMAGE_MAX_BPL);
> > +
> > +     pix->sizeimage = pix->height * pix->bytesperline;
> > +}
> > +
> > +static void unicam_calc_meta_size_bpl(struct unicam_device *unicam,
> > +                                   const struct unicam_format_info *fmtinfo,
> > +                                   struct v4l2_meta_format *meta)
> > +{
> > +     v4l_bound_align_image(&meta->width, UNICAM_META_MIN_WIDTH,
> > +                           UNICAM_META_MAX_WIDTH, 0,
> > +                           &meta->height, UNICAM_META_MIN_HEIGHT,
> > +                           UNICAM_META_MAX_HEIGHT, 0, 0);
> > +
> > +     meta->bytesperline = ALIGN(meta->width * fmtinfo->depth / 8,
> > +                                UNICAM_DMA_BPL_ALIGNMENT);
> > +     meta->buffersize = meta->height * meta->bytesperline;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Hardware handling
> > + */
> > +
>
> As this has been used for years in BSP driver, I won't go in detail in
> the HW handling functions
>
> > +static inline void unicam_clk_write(struct unicam_device *unicam, u32 val)
> > +{
> > +     /* Pass the CM_PASSWORD along with the value. */
> > +     writel(val | 0x5a000000, unicam->clk_gate_base);
> > +}
> > +
> > +static inline u32 unicam_reg_read(struct unicam_device *unicam, u32 offset)
> > +{
> > +     return readl(unicam->base + offset);
> > +}
> > +
> > +static inline void unicam_reg_write(struct unicam_device *unicam, u32 offset, u32 val)
> > +{
> > +     writel(val, unicam->base + offset);
> > +}
> > +
> > +static inline int unicam_get_field(u32 value, u32 mask)
> > +{
> > +     return (value & mask) >> __ffs(mask);
> > +}
> > +
> > +static inline void unicam_set_field(u32 *valp, u32 field, u32 mask)
> > +{
> > +     u32 val = *valp;
> > +
> > +     val &= ~mask;
> > +     val |= (field << __ffs(mask)) & mask;
> > +     *valp = val;
> > +}
> > +
> > +static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offset,
> > +                                       u32 field, u32 mask)
> > +{
> > +     u32 val = unicam_reg_read(unicam, offset);
> > +
> > +     unicam_set_field(&val, field, mask);
> > +     unicam_reg_write(unicam, offset, val);
> > +}
> > +
> > +static void unicam_wr_dma_addr(struct unicam_node *node,
> > +                            struct unicam_buffer *buf)
> > +{
> > +     dma_addr_t endaddr = buf->dma_addr + buf->size;
> > +
> > +     if (node->id == UNICAM_IMAGE_NODE) {
> > +             unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
> > +             unicam_reg_write(node->dev, UNICAM_IBEA0, endaddr);
> > +     } else {
> > +             unicam_reg_write(node->dev, UNICAM_DBSA0, buf->dma_addr);
> > +             unicam_reg_write(node->dev, UNICAM_DBEA0, endaddr);
> > +     }
> > +}
> > +
> > +static unsigned int unicam_get_lines_done(struct unicam_device *unicam)
> > +{
> > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +     unsigned int stride = node->fmt.fmt.pix.bytesperline;
> > +     struct unicam_buffer *frm = node->cur_frm;
> > +     dma_addr_t cur_addr;
> > +
> > +     if (!frm)
> > +             return 0;
> > +
> > +     cur_addr = unicam_reg_read(unicam, UNICAM_IBWP);
> > +     return (unsigned int)(cur_addr - frm->dma_addr) / stride;
> > +}
> > +
> > +static void unicam_schedule_next_buffer(struct unicam_node *node)
> > +{
> > +     struct unicam_buffer *buf;
> > +
> > +     buf = list_first_entry(&node->dma_queue, struct unicam_buffer, list);
> > +     node->next_frm = buf;
> > +     list_del(&buf->list);
> > +
> > +     unicam_wr_dma_addr(node, buf);
> > +}
> > +
> > +static void unicam_schedule_dummy_buffer(struct unicam_node *node)
> > +{
> > +     int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
> > +
> > +     dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
> > +
> > +     unicam_wr_dma_addr(node, &node->dummy_buf);
> > +
> > +     node->next_frm = NULL;
> > +}
> > +
> > +static void unicam_process_buffer_complete(struct unicam_node *node,
> > +                                        unsigned int sequence)
> > +{
> > +     node->cur_frm->vb.field = node->fmt.fmt.pix.field;
> > +     node->cur_frm->vb.sequence = sequence;
> > +
> > +     vb2_buffer_done(&node->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
> > +}
> > +
> > +static void unicam_queue_event_sof(struct unicam_device *unicam)
> > +{
> > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +
> > +     struct v4l2_event event = {
> > +             .type = V4L2_EVENT_FRAME_SYNC,
> > +             .u.frame_sync.frame_sequence = unicam->sequence,
> > +     };
> > +
> > +     v4l2_event_queue(&node->video_dev, &event);
> > +}
> > +
> > +static irqreturn_t unicam_isr(int irq, void *dev)
> > +{
> > +     struct unicam_device *unicam = dev;
> > +     unsigned int lines_done = unicam_get_lines_done(dev);
> > +     unsigned int sequence = unicam->sequence;
> > +     unsigned int i;
> > +     u32 ista, sta;
> > +     bool fe;
> > +     u64 ts;
> > +
> > +     sta = unicam_reg_read(unicam, UNICAM_STA);
> > +     /* Write value back to clear the interrupts */
> > +     unicam_reg_write(unicam, UNICAM_STA, sta);
> > +
> > +     ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > +     /* Write value back to clear the interrupts */
> > +     unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > +
> > +     dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > +             ista, sta, sequence, lines_done);
> > +
> > +     if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > +             return IRQ_HANDLED;
> > +
> > +     /*
> > +      * Look for either the Frame End interrupt or the Packet Capture status
> > +      * to signal a frame end.
> > +      */
> > +     fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > +
> > +     /*
> > +      * We must run the frame end handler first. If we have a valid next_frm
> > +      * and we get a simultaneout FE + FS interrupt, running the FS handler
> > +      * first would null out the next_frm ptr and we would have lost the
> > +      * buffer forever.
> > +      */
> > +     if (fe) {
> > +             /*
> > +              * Ensure we have swapped buffers already as we can't
> > +              * stop the peripheral. If no buffer is available, use a
> > +              * dummy buffer to dump out frames until we get a new buffer
> > +              * to use.
> > +              */
> > +             for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +                     if (!unicam->node[i].streaming)
> > +                             continue;
> > +
> > +                     /*
> > +                      * If cur_frm == next_frm, it means we have not had
> > +                      * a chance to swap buffers, likely due to having
> > +                      * multiple interrupts occurring simultaneously (like FE
> > +                      * + FS + LS). In this case, we cannot signal the buffer
> > +                      * as complete, as the HW will reuse that buffer.
> > +                      */
> > +                     if (unicam->node[i].cur_frm &&
> > +                         unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > +                             unicam_process_buffer_complete(&unicam->node[i],
> > +                                                            sequence);
> > +                     unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > +             }
> > +             unicam->sequence++;
> > +     }
> > +
> > +     if (ista & UNICAM_FSI) {
> > +             /*
> > +              * Timestamp is to be when the first data byte was captured,
> > +              * aka frame start.
> > +              */
> > +             ts = ktime_get_ns();
> > +             for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +                     if (!unicam->node[i].streaming)
> > +                             continue;
> > +
> > +                     if (unicam->node[i].cur_frm)
> > +                             unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > +                                                             ts;
> > +                     else
> > +                             dev_dbg(unicam->v4l2_dev.dev,
> > +                                     "ISR: [%d] Dropping frame, buffer not available at FS\n",
> > +                                     i);
> > +                     /*
> > +                      * Set the next frame output to go to a dummy frame
> > +                      * if we have not managed to obtain another frame
> > +                      * from the queue.
> > +                      */
> > +                     unicam_schedule_dummy_buffer(&unicam->node[i]);
> > +             }
> > +
> > +             unicam_queue_event_sof(unicam);
> > +     }
> > +
> > +     /*
> > +      * Cannot swap buffer at frame end, there may be a race condition
> > +      * where the HW does not actually swap it if the new frame has
> > +      * already started.
> > +      */
> > +     if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > +             for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +                     if (!unicam->node[i].streaming)
> > +                             continue;
> > +
> > +                     spin_lock(&unicam->node[i].dma_queue_lock);
> > +                     if (!list_empty(&unicam->node[i].dma_queue) &&
> > +                         !unicam->node[i].next_frm)
> > +                             unicam_schedule_next_buffer(&unicam->node[i]);
> > +                     spin_unlock(&unicam->node[i].dma_queue_lock);
> > +             }
> > +     }
> > +
> > +     if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > +             /* Switch out of trigger mode if selected */
> > +             unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > +             unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > +     }
> > +     return IRQ_HANDLED;
> > +}
> > +
> > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > +{
> > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +     u32 pack, unpack;
> > +     u32 val;
> > +
> > +     if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > +             unpack = UNICAM_PUM_NONE;
> > +             pack = UNICAM_PPM_NONE;
> > +     } else {
> > +             switch (node->fmtinfo->depth) {
> > +             case 8:
> > +                     unpack = UNICAM_PUM_UNPACK8;
> > +                     break;
> > +             case 10:
> > +                     unpack = UNICAM_PUM_UNPACK10;
> > +                     break;
> > +             case 12:
> > +                     unpack = UNICAM_PUM_UNPACK12;
> > +                     break;
> > +             case 14:
> > +                     unpack = UNICAM_PUM_UNPACK14;
> > +                     break;
> > +             case 16:
> > +                     unpack = UNICAM_PUM_UNPACK16;
> > +                     break;
> > +             default:
> > +                     unpack = UNICAM_PUM_NONE;
> > +                     break;
> > +             }
> > +
> > +             /* Repacking is always to 16bpp */
> > +             pack = UNICAM_PPM_PACK16;
> > +     }
> > +
> > +     val = 0;
> > +     unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> > +     unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> > +     unicam_reg_write(unicam, UNICAM_IPIPE, val);
> > +}
> > +
> > +static void unicam_cfg_image_id(struct unicam_device *unicam)
> > +{
> > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +
> > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +             /* CSI2 mode, hardcode VC 0 for now. */
> > +             unicam_reg_write(unicam, UNICAM_IDI0,
> > +                              (0 << 6) | node->fmtinfo->csi_dt);
> > +     } else {
> > +             /* CCP2 mode */
> > +             unicam_reg_write(unicam, UNICAM_IDI0,
> > +                              0x80 | node->fmtinfo->csi_dt);
> > +     }
> > +}
> > +
> > +static void unicam_enable_ed(struct unicam_device *unicam)
> > +{
> > +     u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> > +
> > +     unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> > +     /* Do not wrap at the end of the embedded data buffer */
> > +     unicam_set_field(&val, 0, UNICAM_DBOB);
> > +
> > +     unicam_reg_write(unicam, UNICAM_DCS, val);
> > +}
> > +
> > +static void unicam_start_rx(struct unicam_device *unicam,
> > +                         struct unicam_buffer *buf)
> > +{
> > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +     int line_int_freq = node->fmt.fmt.pix.height >> 2;
> > +     unsigned int i;
> > +     u32 val;
> > +
> > +     if (line_int_freq < 128)
> > +             line_int_freq = 128;
> > +
> > +     /* Enable lane clocks */
> > +     val = 1;
> > +     for (i = 0; i < unicam->active_data_lanes; i++)
> > +             val = val << 2 | 1;
> > +     unicam_clk_write(unicam, val);
> > +
> > +     /* Basic init */
> > +     unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> > +
> > +     /* Enable analogue control, and leave in reset. */
> > +     val = UNICAM_AR;
> > +     unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> > +     unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> > +     unicam_reg_write(unicam, UNICAM_ANA, val);
> > +     usleep_range(1000, 2000);
> > +
> > +     /* Come out of reset */
> > +     unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> > +
> > +     /* Peripheral reset */
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > +
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > +
> > +     /* Enable Rx control. */
> > +     val = unicam_reg_read(unicam, UNICAM_CTRL);
> > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +             unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> > +             unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> > +     } else {
> > +             unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> > +             unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> > +     }
> > +     /* Packet framer timeout */
> > +     unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> > +     unicam_set_field(&val, 128, UNICAM_OET_MASK);
> > +     unicam_reg_write(unicam, UNICAM_CTRL, val);
> > +
> > +     unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> > +     unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> > +
> > +     /* AXI bus access QoS setup */
> > +     val = unicam_reg_read(unicam, UNICAM_PRI);
> > +     unicam_set_field(&val, 0, UNICAM_BL_MASK);
> > +     unicam_set_field(&val, 0, UNICAM_BS_MASK);
> > +     unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> > +     unicam_set_field(&val, 8, UNICAM_NP_MASK);
> > +     unicam_set_field(&val, 2, UNICAM_PT_MASK);
> > +     unicam_set_field(&val, 1, UNICAM_PE);
> > +     unicam_reg_write(unicam, UNICAM_PRI, val);
> > +
> > +     unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> > +
> > +     /* Always start in trigger frame capture mode (UNICAM_FCM set) */
> > +     val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> > +     unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> > +     unicam_reg_write(unicam, UNICAM_ICTL, val);
> > +     unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> > +     unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> > +
> > +     /* tclk_term_en */
> > +     unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> > +     /* tclk_settle */
> > +     unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> > +     /* td_term_en */
> > +     unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> > +     /* ths_settle */
> > +     unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> > +     /* trx_enable */
> > +     unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> > +
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> > +
> > +     /* Packet compare setup - required to avoid missing frame ends */
> > +     val = 0;
> > +     unicam_set_field(&val, 1, UNICAM_PCE);
> > +     unicam_set_field(&val, 1, UNICAM_GI);
> > +     unicam_set_field(&val, 1, UNICAM_CPH);
> > +     unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> > +     unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> > +     unicam_reg_write(unicam, UNICAM_CMP0, val);
> > +
> > +     /* Enable clock lane and set up terminations */
> > +     val = 0;
> > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +             /* CSI2 */
> > +             unicam_set_field(&val, 1, UNICAM_CLE);
> > +             unicam_set_field(&val, 1, UNICAM_CLLPE);
> > +             if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > +                     unicam_set_field(&val, 1, UNICAM_CLTRE);
> > +                     unicam_set_field(&val, 1, UNICAM_CLHSE);
> > +             }
> > +     } else {
> > +             /* CCP2 */
> > +             unicam_set_field(&val, 1, UNICAM_CLE);
> > +             unicam_set_field(&val, 1, UNICAM_CLHSE);
> > +             unicam_set_field(&val, 1, UNICAM_CLTRE);
> > +     }
> > +     unicam_reg_write(unicam, UNICAM_CLK, val);
> > +
> > +     /*
> > +      * Enable required data lanes with appropriate terminations.
> > +      * The same value needs to be written to UNICAM_DATn registers for
> > +      * the active lanes, and 0 for inactive ones.
> > +      */
> > +     val = 0;
> > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +             /* CSI2 */
> > +             unicam_set_field(&val, 1, UNICAM_DLE);
> > +             unicam_set_field(&val, 1, UNICAM_DLLPE);
> > +             if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > +                     unicam_set_field(&val, 1, UNICAM_DLTRE);
> > +                     unicam_set_field(&val, 1, UNICAM_DLHSE);
> > +             }
> > +     } else {
> > +             /* CCP2 */
> > +             unicam_set_field(&val, 1, UNICAM_DLE);
> > +             unicam_set_field(&val, 1, UNICAM_DLHSE);
> > +             unicam_set_field(&val, 1, UNICAM_DLTRE);
> > +     }
> > +     unicam_reg_write(unicam, UNICAM_DAT0, val);
> > +
> > +     if (unicam->active_data_lanes == 1)
> > +             val = 0;
> > +     unicam_reg_write(unicam, UNICAM_DAT1, val);
> > +
> > +     if (unicam->max_data_lanes > 2) {
> > +             /*
> > +              * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> > +              * instance supports more than 2 data lanes.
> > +              */
> > +             if (unicam->active_data_lanes == 2)
> > +                     val = 0;
> > +             unicam_reg_write(unicam, UNICAM_DAT2, val);
> > +
> > +             if (unicam->active_data_lanes == 3)
> > +                     val = 0;
> > +             unicam_reg_write(unicam, UNICAM_DAT3, val);
> > +     }
> > +
> > +     unicam_reg_write(unicam, UNICAM_IBLS,
> > +                      node->fmt.fmt.pix.bytesperline);
> > +     unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> > +     unicam_set_packing_config(unicam);
> > +     unicam_cfg_image_id(unicam);
> > +
> > +     val = unicam_reg_read(unicam, UNICAM_MISC);
> > +     unicam_set_field(&val, 1, UNICAM_FL0);
> > +     unicam_set_field(&val, 1, UNICAM_FL1);
> > +     unicam_reg_write(unicam, UNICAM_MISC, val);
> > +
> > +     /* Enable peripheral */
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> > +
> > +     /* Load image pointers */
> > +     unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> > +
> > +     /*
> > +      * Enable trigger only for the first frame to
> > +      * sync correctly to the FS from the source.
> > +      */
> > +     unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > +}
> > +
> > +static void unicam_start_metadata(struct unicam_device *unicam,
> > +                               struct unicam_buffer *buf)
> > +{
> > +     struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
> > +
> > +     unicam_enable_ed(unicam);
> > +     unicam_wr_dma_addr(node, buf);
> > +     unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
> > +}
> > +
> > +static void unicam_disable(struct unicam_device *unicam)
> > +{
> > +     /* Analogue lane control disable */
> > +     unicam_reg_write_field(unicam, UNICAM_ANA, 1, UNICAM_DDL);
> > +
> > +     /* Stop the output engine */
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_SOE);
> > +
> > +     /* Disable the data lanes. */
> > +     unicam_reg_write(unicam, UNICAM_DAT0, 0);
> > +     unicam_reg_write(unicam, UNICAM_DAT1, 0);
> > +
> > +     if (unicam->max_data_lanes > 2) {
> > +             unicam_reg_write(unicam, UNICAM_DAT2, 0);
> > +             unicam_reg_write(unicam, UNICAM_DAT3, 0);
> > +     }
> > +
> > +     /* Peripheral reset */
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > +     usleep_range(50, 100);
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > +
> > +     /* Disable peripheral */
> > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > +
> > +     /* Clear ED setup */
> > +     unicam_reg_write(unicam, UNICAM_DCS, 0);
> > +
> > +     /* Disable all lane clocks */
> > +     unicam_clk_write(unicam, 0);
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * V4L2 subdev operations
> > + */
> > +
> > +static int __unicam_subdev_set_routing(struct v4l2_subdev *sd,
> > +                                    struct v4l2_subdev_state *state,
> > +                                    struct v4l2_subdev_krouting *routing)
> > +{
> > +     struct v4l2_subdev_route *route;
> > +     int ret;
> > +
> > +     ret = v4l2_subdev_routing_validate(sd, routing,
> > +                                        V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = v4l2_subdev_set_routing(sd, state, routing);
> > +     if (ret)
> > +             return ret;
> > +
> > +     for_each_active_route(&state->routing, route) {
> > +             const struct v4l2_mbus_framefmt *def_fmt;
> > +             struct v4l2_mbus_framefmt *fmt;
> > +
> > +             if (route->source_pad == UNICAM_SD_PAD_SOURCE_IMAGE)
> > +                     def_fmt = &unicam_default_image_format;
> > +             else
> > +                     def_fmt = &unicam_default_meta_format;
> > +
> > +             fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
> > +                                                route->sink_stream);
> > +             *fmt = *def_fmt;
> > +             fmt = v4l2_subdev_state_get_format(state, route->source_pad,
> > +                                                route->source_stream);
> > +             *fmt = *def_fmt;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_subdev_init_state(struct v4l2_subdev *sd,
> > +                                 struct v4l2_subdev_state *state)
> > +{
> > +     struct v4l2_subdev_route routes[] = {
> > +             {
> > +                     .sink_pad = UNICAM_SD_PAD_SINK,
> > +                     .sink_stream = 0,
> > +                     .source_pad = UNICAM_SD_PAD_SOURCE_IMAGE,
> > +                     .source_stream = 0,
> > +                     .flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
> > +             },
> > +     };
> > +
> > +     struct v4l2_subdev_krouting routing = {
> > +             .len_routes = ARRAY_SIZE(routes),
> > +             .num_routes = ARRAY_SIZE(routes),
> > +             .routes = routes,
> > +     };
> > +
> > +     /* Initialize routing to single route to the fist source pad. */
> > +     return __unicam_subdev_set_routing(sd, state, &routing);
> > +}
> > +
> > +static int unicam_subdev_enum_mbus_code(struct v4l2_subdev *sd,
> > +                                     struct v4l2_subdev_state *state,
> > +                                     struct v4l2_subdev_mbus_code_enum *code)
> > +{
> > +     u32 pad, stream;
> > +     int ret;
> > +
> > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > +                                                 code->pad, code->stream,
> > +                                                 &pad, &stream);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (unicam_sd_pad_is_source(code->pad)) {
> > +             /* No transcoding, source and sink codes must match. */
> > +             const struct v4l2_mbus_framefmt *fmt;
> > +
> > +             fmt = v4l2_subdev_state_get_format(state, pad, stream);
> > +             if (!fmt)
> > +                     return -EINVAL;
> > +
> > +             if (code->index > 0)
> > +                     return -EINVAL;
> > +
> > +             code->code = fmt->code;
> > +     } else {
> > +             const struct unicam_format_info *formats;
> > +             unsigned int num_formats;
> > +
> > +             if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > +                     formats = unicam_image_formats;
> > +                     num_formats = ARRAY_SIZE(unicam_image_formats);
> > +             } else {
> > +                     formats = unicam_meta_formats;
> > +                     num_formats = ARRAY_SIZE(unicam_meta_formats);
> > +             }
> > +
> > +             if (code->index >= num_formats)
> > +                     return -EINVAL;
> > +
> > +             code->code = formats[code->index].code;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_subdev_enum_frame_size(struct v4l2_subdev *sd,
> > +                                      struct v4l2_subdev_state *state,
> > +                                      struct v4l2_subdev_frame_size_enum *fse)
> > +{
> > +     u32 pad, stream;
> > +     int ret;
> > +
> > +     if (fse->index > 0)
> > +             return -EINVAL;
> > +
> > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing, fse->pad,
> > +                                                 fse->stream, &pad,
> > +                                                 &stream);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (unicam_sd_pad_is_source(fse->pad)) {
> > +             /* No transcoding, source and sink formats must match. */
> > +             const struct v4l2_mbus_framefmt *fmt;
> > +
> > +             fmt = v4l2_subdev_state_get_format(state, pad, stream);
> > +             if (!fmt)
> > +                     return -EINVAL;
> > +
> > +             if (fse->code != fmt->code)
> > +                     return -EINVAL;
> > +
> > +             fse->min_width = fmt->width;
> > +             fse->max_width = fmt->width;
> > +             fse->min_height = fmt->height;
> > +             fse->max_height = fmt->height;
> > +     } else {
> > +             const struct unicam_format_info *fmtinfo;
> > +
> > +             fmtinfo = unicam_find_format_by_code(fse->code, pad);
> > +             if (!fmtinfo)
> > +                     return -EINVAL;
> > +
> > +             if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > +                     fse->min_width = UNICAM_IMAGE_MIN_WIDTH;
> > +                     fse->max_width = UNICAM_IMAGE_MAX_WIDTH;
> > +                     fse->min_height = UNICAM_IMAGE_MIN_HEIGHT;
> > +                     fse->max_height = UNICAM_IMAGE_MAX_HEIGHT;
> > +             } else {
> > +                     fse->min_width = UNICAM_META_MIN_WIDTH;
> > +                     fse->max_width = UNICAM_META_MAX_WIDTH;
> > +                     fse->min_height = UNICAM_META_MIN_HEIGHT;
> > +                     fse->max_height = UNICAM_META_MAX_HEIGHT;
> > +             }
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_subdev_set_format(struct v4l2_subdev *sd,
> > +                                 struct v4l2_subdev_state *state,
> > +                                 struct v4l2_subdev_format *format)
> > +{
> > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > +     struct v4l2_mbus_framefmt *sink_format, *source_format;
> > +     const struct unicam_format_info *fmtinfo;
> > +     u32 source_pad, source_stream;
> > +     int ret;
> > +
> > +     if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
> > +         unicam->subdev.streaming)
> > +             return -EBUSY;
> > +
> > +     /* No transcoding, source and sink formats must match. */
> > +     if (unicam_sd_pad_is_source(format->pad))
> > +             return v4l2_subdev_get_fmt(sd, state, format);
> > +
> > +     /*
> > +      * Allowed formats for the stream on the sink pad depend on what source
> > +      * pad the stream is routed to. Find the corresponding source pad and
> > +      * use it to validate the media bus code.
> > +      */
> > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > +                                                 format->pad, format->stream,
> > +                                                 &source_pad, &source_stream);
> > +     if (ret)
> > +             return ret;
> > +
> > +     fmtinfo = unicam_find_format_by_code(format->format.code, source_pad);
> > +     if (!fmtinfo) {
> > +             fmtinfo = source_pad == UNICAM_SD_PAD_SOURCE_IMAGE
> > +                     ? &unicam_image_formats[0] : &unicam_meta_formats[0];
> > +             format->format.code = fmtinfo->code;
> > +     }
> > +
> > +     if (source_pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > +             format->format.width = clamp_t(unsigned int,
> > +                                            format->format.width,
> > +                                            UNICAM_IMAGE_MIN_WIDTH,
> > +                                            UNICAM_IMAGE_MAX_WIDTH);
> > +             format->format.height = clamp_t(unsigned int,
> > +                                             format->format.height,
> > +                                             UNICAM_IMAGE_MIN_HEIGHT,
> > +                                             UNICAM_IMAGE_MAX_HEIGHT);
> > +             format->format.field = V4L2_FIELD_NONE;
> > +     } else {
> > +             format->format.width = clamp_t(unsigned int,
> > +                                            format->format.width,
> > +                                            UNICAM_META_MIN_WIDTH,
> > +                                            UNICAM_META_MAX_WIDTH);
> > +             format->format.height = clamp_t(unsigned int,
> > +                                             format->format.height,
> > +                                             UNICAM_META_MIN_HEIGHT,
> > +                                             UNICAM_META_MAX_HEIGHT);
> > +             format->format.field = V4L2_FIELD_NONE;
> > +
> > +             /* Colorspace don't apply to metadata. */
> > +             format->format.colorspace = 0;
> > +             format->format.ycbcr_enc = 0;
> > +             format->format.quantization = 0;
> > +             format->format.xfer_func = 0;
> > +     }
> > +
> > +     sink_format = v4l2_subdev_state_get_format(state, format->pad,
> > +                                                format->stream);
> > +     source_format = v4l2_subdev_state_get_format(state, source_pad,
> > +                                                  source_stream);
> > +     *sink_format = format->format;
> > +     *source_format = format->format;
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_subdev_set_routing(struct v4l2_subdev *sd,
> > +                                  struct v4l2_subdev_state *state,
> > +                                  enum v4l2_subdev_format_whence which,
> > +                                  struct v4l2_subdev_krouting *routing)
> > +{
> > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > +
> > +     if (which == V4L2_SUBDEV_FORMAT_ACTIVE && unicam->subdev.streaming)
> > +             return -EBUSY;
> > +
> > +     return __unicam_subdev_set_routing(sd, state, routing);
> > +}
> > +
> > +static int unicam_sd_enable_streams(struct v4l2_subdev *sd,
> > +                                 struct v4l2_subdev_state *state, u32 pad,
> > +                                 u64 streams_mask)
> > +{
> > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > +     u32 other_pad, other_stream;
> > +     int ret;
> > +
> > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> > +                                                 &other_pad, &other_stream);
> > +     if (ret)
> > +             return ret;
> > +
> > +     unicam->sequence = 0;
> > +
> > +     ret = v4l2_subdev_enable_streams(unicam->sensor.subdev,
> > +                                      unicam->sensor.pad->index,
> > +                                      BIT(other_stream));
> > +     if (ret) {
> > +             dev_err(unicam->dev, "stream on failed in subdev\n");
> > +             return ret;
> > +     }
> > +
> > +     unicam->subdev.streaming = true;
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_sd_disable_streams(struct v4l2_subdev *sd,
> > +                                  struct v4l2_subdev_state *state, u32 pad,
> > +                                  u64 streams_mask)
> > +{
> > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > +     u32 other_pad, other_stream;
> > +     int ret;
> > +
> > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> > +                                                 &other_pad, &other_stream);
> > +     if (ret)
> > +             return ret;
> > +
> > +     v4l2_subdev_disable_streams(unicam->sensor.subdev,
> > +                                 unicam->sensor.pad->index,
> > +                                 BIT(other_stream));
> > +
> > +     unicam->subdev.streaming = false;
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_pad_ops unicam_subdev_pad_ops = {
> > +     .enum_mbus_code         = unicam_subdev_enum_mbus_code,
> > +     .enum_frame_size        = unicam_subdev_enum_frame_size,
> > +     .get_fmt                = v4l2_subdev_get_fmt,
> > +     .set_fmt                = unicam_subdev_set_format,
> > +     .set_routing            = unicam_subdev_set_routing,
> > +     .enable_streams         = unicam_sd_enable_streams,
> > +     .disable_streams        = unicam_sd_disable_streams,
> > +};
> > +
> > +static const struct v4l2_subdev_ops unicam_subdev_ops = {
> > +     .pad                    = &unicam_subdev_pad_ops,
> > +};
> > +
> > +static const struct v4l2_subdev_internal_ops unicam_subdev_internal_ops = {
> > +     .init_state             = unicam_subdev_init_state,
> > +};
> > +
> > +static const struct media_entity_operations unicam_subdev_media_ops = {
> > +     .link_validate          = v4l2_subdev_link_validate,
> > +     .has_pad_interdep       = v4l2_subdev_has_pad_interdep,
> > +};
> > +
> > +static int unicam_subdev_init(struct unicam_device *unicam)
> > +{
> > +     struct v4l2_subdev *sd = &unicam->subdev.sd;
> > +     int ret;
> > +
> > +     v4l2_subdev_init(sd, &unicam_subdev_ops);
> > +     sd->internal_ops = &unicam_subdev_internal_ops;
> > +     v4l2_set_subdevdata(sd, unicam);
> > +
> > +     sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> > +     sd->entity.ops = &unicam_subdev_media_ops;
> > +     sd->dev = unicam->dev;
> > +     sd->owner = THIS_MODULE;
> > +     sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
> > +
> > +     strscpy(sd->name, "unicam", sizeof(sd->name));
> > +
> > +     unicam->subdev.pads[UNICAM_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> > +     unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_IMAGE].flags = MEDIA_PAD_FL_SOURCE;
> > +     unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_METADATA].flags = MEDIA_PAD_FL_SOURCE;
> > +
> > +     ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(unicam->subdev.pads),
> > +                                  unicam->subdev.pads);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "Failed to initialize media entity: %d\n",
> > +                     ret);
> > +             return ret;
> > +     }
> > +
> > +     ret = v4l2_subdev_init_finalize(sd);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "Failed to initialize subdev: %d\n", ret);
> > +             goto err_entity;
> > +     }
> > +
> > +     ret = v4l2_device_register_subdev(&unicam->v4l2_dev, sd);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "Failed to register subdev: %d\n", ret);
> > +             goto err_subdev;
> > +     }
> > +
> > +     return 0;
> > +
> > +err_subdev:
> > +     v4l2_subdev_cleanup(sd);
> > +err_entity:
> > +     media_entity_cleanup(&sd->entity);
> > +     return ret;
> > +}
> > +
> > +static void unicam_subdev_cleanup(struct unicam_device *unicam)
> > +{
> > +     v4l2_subdev_cleanup(&unicam->subdev.sd);
> > +     media_entity_cleanup(&unicam->subdev.sd.entity);
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Videobuf2 queue operations
> > + */
> > +
> > +static int unicam_queue_setup(struct vb2_queue *vq,
> > +                           unsigned int *nbuffers,
> > +                           unsigned int *nplanes,
> > +                           unsigned int sizes[],
> > +                           struct device *alloc_devs[])
> > +{
> > +     struct unicam_node *node = vb2_get_drv_priv(vq);
> > +     u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > +              : node->fmt.fmt.meta.buffersize;
> > +
> > +     if (vq->num_buffers + *nbuffers < 3)
>
> Why 3 ? Are these dummies ?
>
> > +             *nbuffers = 3 - vq->num_buffers;
> > +
> > +     if (*nplanes) {
> > +             if (sizes[0] < size) {
> > +                     dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> > +                             sizes[0], size);
> > +                     return -EINVAL;
> > +             }
> > +             size = sizes[0];
> > +     }
> > +
> > +     *nplanes = 1;
> > +     sizes[0] = size;
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_buffer_prepare(struct vb2_buffer *vb)
> > +{
> > +     struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > +     struct unicam_buffer *buf = to_unicam_buffer(vb);
> > +     u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > +              : node->fmt.fmt.meta.buffersize;
> > +
> > +     if (vb2_plane_size(vb, 0) < size) {
> > +             dev_dbg(node->dev->dev,
> > +                     "data will not fit into plane (%lu < %u)\n",
> > +                     vb2_plane_size(vb, 0), size);
> > +             return -EINVAL;
> > +     }
> > +
> > +     buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> > +     buf->size = size;
> > +
> > +     vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> > +
> > +     return 0;
> > +}
> > +
> > +static void unicam_return_buffers(struct unicam_node *node,
> > +                               enum vb2_buffer_state state)
> > +{
> > +     struct unicam_buffer *buf, *tmp;
> > +
> > +     list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> > +             list_del(&buf->list);
> > +             vb2_buffer_done(&buf->vb.vb2_buf, state);
> > +     }
> > +
> > +     if (node->cur_frm)
> > +             vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> > +                             state);
> > +     if (node->next_frm && node->cur_frm != node->next_frm)
> > +             vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> > +                             state);
> > +
> > +     node->cur_frm = NULL;
> > +     node->next_frm = NULL;
> > +}
> > +
> > +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> > +{
> > +     struct unicam_node *node = vb2_get_drv_priv(vq);
> > +     struct unicam_device *unicam = node->dev;
> > +     struct v4l2_subdev_state *state;
> > +     struct unicam_buffer *buf;
> > +     unsigned long flags;
> > +     int ret;
> > +     u32 pad, stream;
> > +     u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +                                          : UNICAM_SD_PAD_SOURCE_METADATA;
> > +
> > +     /* Look for the route for the given pad and stream. */
> > +     state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > +                                                 remote_pad, 0,
> > +                                                 &pad, &stream);
> > +     v4l2_subdev_unlock_state(state);
> > +
> > +     if (ret)
> > +             goto err_return_buffers;

You've dropped calling get_mbus_config from in or around this area,
therefore any device that supports dynamic switching on number of data
lanes (eg tc358743) is broken.
Docs guidance is
"Callers should make sure they get the most up-to-date as possible
configuration from the remote end, likely calling this operation as
close as possible to stream on time"
https://www.kernel.org/doc/html/latest/driver-api/media/v4l2-subdev.html?highlight=get_mbus_config

> > +
> > +     dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> > +             unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> > +             is_metadata_node(node) ? "metadata" : "image");
> > +
> > +     /* The metadata node can't be started alone. */
> > +     if (is_metadata_node(node)) {
> > +             if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
>
> Does it mean the metadata node has to be started second, or should
> this be made a nop and the metadata node gets started once the image
> node is started too ? I'm fine with the constraint of having the
> metadata node being started second fwiw

This has been flipped from the downstream implementation.
Downstream we expected the metadata node to be enabled first, but it
wouldn't get started until the image node was enabled.

Things like sequence numbers come to mind now that this is enabling
the image node first. If the image node has produced the first frame
before the metadata node has been enabled, then as I read it the
sequence numbers for the two nodes should be different - there haven't
really been any dropped frames as you hadn't enabled the node.

I'd also want to confirm what the behaviour is if the frame has
already started before the metadata node is enabled. Embedded data is
almost always sent before the image data, so have we potentially
missed it for the current frame, but at the end of frame are going to
return both buffers?

> > +                     dev_err(unicam->dev,
> > +                             "Can't start metadata without image\n");
> > +                     ret = -EINVAL;
> > +                     goto err_return_buffers;
> > +             }
> > +
> > +             spin_lock_irqsave(&node->dma_queue_lock, flags);
> > +             buf = list_first_entry(&node->dma_queue,
> > +                                    struct unicam_buffer, list);
> > +             dev_dbg(unicam->dev, "buffer %p\n", buf);
>
> Is this useful ?
>
> > +             node->cur_frm = buf;
> > +             node->next_frm = buf;
> > +             list_del(&buf->list);
> > +             spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > +
> > +             unicam_start_metadata(unicam, buf);
> > +             node->streaming = true;
> > +             return 0;
> > +     }
> > +
> > +     ret = pm_runtime_resume_and_get(unicam->dev);
> > +     if (ret < 0) {
> > +             dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> > +             goto err_return_buffers;
> > +     }
> > +
> > +     ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> > +     if (ret < 0) {
> > +             dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
>
> Isn't this an err ?
>
> > +             goto err_pm_put;
> > +     }
> > +
> > +     spin_lock_irqsave(&node->dma_queue_lock, flags);
> > +     buf = list_first_entry(&node->dma_queue,
> > +                            struct unicam_buffer, list);
> > +     dev_dbg(unicam->dev, "buffer %p\n", buf);
> > +     node->cur_frm = buf;
> > +     node->next_frm = buf;
> > +     list_del(&buf->list);
> > +     spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > +
> > +     unicam_start_rx(unicam, buf);
> > +
> > +     ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
>
> A bit confused by the API here, shouldn't we also do this for embedded
> data ?
>
> > +     if (ret < 0) {
> > +             dev_err(unicam->dev, "stream on failed in subdev\n");
> > +             goto error_pipeline;
> > +     }
> > +
> > +     node->streaming = true;
> > +
> > +     return 0;
> > +
> > +error_pipeline:
> > +     video_device_pipeline_stop(&node->video_dev);
> > +err_pm_put:
> > +     pm_runtime_put_sync(unicam->dev);
> > +err_return_buffers:
> > +     unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> > +     return ret;
> > +}
> > +
> > +static void unicam_stop_streaming(struct vb2_queue *vq)
> > +{
> > +     struct unicam_node *node = vb2_get_drv_priv(vq);
> > +     struct unicam_device *unicam = node->dev;
> > +     u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +                                                : UNICAM_SD_PAD_SOURCE_METADATA;
> > +
> > +     node->streaming = false;
> > +
> > +     v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> > +                                 BIT(0));
> > +
> > +     /* We can stream only with the image node. */
> > +     if (is_metadata_node(node)) {
> > +             /*
> > +              * Allow the hardware to spin in the dummy buffer.
> > +              * This is only really needed if the embedded data pad is
> > +              * disabled before the image pad.
> > +              */
> > +             unicam_wr_dma_addr(node, &node->dummy_buf);
> > +             goto dequeue_buffers;
> > +     }
> > +
> > +     unicam_disable(unicam);
> > +
> > +     video_device_pipeline_stop(&node->video_dev);
> > +     pm_runtime_put(unicam->dev);
> > +
> > +dequeue_buffers:
> > +     /* Clear all queued buffers for the node */
> > +     unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> > +}
> > +
> > +static void unicam_buffer_queue(struct vb2_buffer *vb)
> > +{
> > +     struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > +     struct unicam_buffer *buf = to_unicam_buffer(vb);
> > +
> > +     spin_lock_irq(&node->dma_queue_lock);
> > +     list_add_tail(&buf->list, &node->dma_queue);
> > +     spin_unlock_irq(&node->dma_queue_lock);
> > +}
> > +
> > +static const struct vb2_ops unicam_video_qops = {
> > +     .queue_setup            = unicam_queue_setup,
> > +     .wait_prepare           = vb2_ops_wait_prepare,
> > +     .wait_finish            = vb2_ops_wait_finish,
> > +     .buf_prepare            = unicam_buffer_prepare,
> > +     .start_streaming        = unicam_start_streaming,
> > +     .stop_streaming         = unicam_stop_streaming,
> > +     .buf_queue              = unicam_buffer_queue,
> > +};
> > +
> > +/* -----------------------------------------------------------------------------
> > + *  V4L2 video device operations
> > + */
> > +
> > +static int unicam_querycap(struct file *file, void *priv,
> > +                        struct v4l2_capability *cap)
> > +{
> > +     strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> > +     strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> > +
> > +     cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> > +                            struct v4l2_fmtdesc *f)
> > +{
> > +     unsigned int index;
> > +     unsigned int i;
> > +
> > +     for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> > +             if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> > +                     continue;
> > +
> > +             if (index == f->index) {
> > +                     f->pixelformat = unicam_image_formats[i].fourcc;
> > +                     return 0;
> > +             }
> > +
> > +             index++;
> > +
> > +             if (!unicam_image_formats[i].unpacked_fourcc)
> > +                     continue;
> > +
> > +             if (index == f->index) {
> > +                     f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> > +                     return 0;
> > +             }
> > +
> > +             index++;
> > +     }
> > +
> > +     return -EINVAL;
> > +}
> > +
> > +static int unicam_g_fmt_vid(struct file *file, void *priv,
> > +                         struct v4l2_format *f)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +
> > +     *f = node->fmt;
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct unicam_format_info *
> > +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> > +{
> > +     const struct unicam_format_info *fmtinfo;
> > +
> > +     /*
> > +      * Default to the first format if the requested pixel format code isn't
> > +      * supported.
> > +      */
> > +     fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> > +                                            UNICAM_SD_PAD_SOURCE_IMAGE);
> > +     if (!fmtinfo) {
> > +             fmtinfo = &unicam_image_formats[0];
> > +             pix->pixelformat = fmtinfo->fourcc;
> > +     }
> > +
> > +     unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> > +
> > +     if (pix->field == V4L2_FIELD_ANY)
> > +             pix->field = V4L2_FIELD_NONE;
> > +
> > +     return fmtinfo;
> > +}
> > +
> > +static int unicam_try_fmt_vid(struct file *file, void *priv,
> > +                           struct v4l2_format *f)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +
> > +     __unicam_try_fmt_vid(node, &f->fmt.pix);
> > +     return 0;
> > +}
> > +
> > +static int unicam_s_fmt_vid(struct file *file, void *priv,
> > +                         struct v4l2_format *f)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +
> > +     if (vb2_is_busy(&node->buffer_queue))
> > +             return -EBUSY;
> > +
> > +     node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> > +     node->fmt = *f;
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> > +                             struct v4l2_fmtdesc *f)
> > +{
> > +     unsigned int i, index;
> > +
> > +     for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> > +             if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
>
> Do we want to allow mbus_code filtering for metadata ? There's a
> 1-to-1 relationship between mbus codes and pixel formats
>
> > +                     continue;
> > +             if (!unicam_meta_formats[i].metadata_fmt)
> > +                     continue;
>
> How can this be false if we're iterating on unicam_meta_formats[] ?
>
> > +
> > +             if (index == f->index) {
> > +                     f->pixelformat = unicam_meta_formats[i].fourcc;
> > +                     f->type = V4L2_BUF_TYPE_META_CAPTURE;
> > +                     return 0;
> > +             }
> > +             index++;
> > +     }
> > +
> > +     return -EINVAL;
> > +}
> > +
> > +static int unicam_g_fmt_meta(struct file *file, void *priv,
> > +                          struct v4l2_format *f)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +
> > +     f->fmt.meta = node->fmt.fmt.meta;
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct unicam_format_info *
> > +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> > +{
> > +     const struct unicam_format_info *fmtinfo;
> > +
> > +     /*
> > +      * Default to the first format if the requested pixel format code isn't
> > +      * supported.
> > +      */
> > +     fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> > +                                            UNICAM_SD_PAD_SOURCE_METADATA);
> > +     if (!fmtinfo) {
> > +             fmtinfo = &unicam_meta_formats[0];
> > +             meta->dataformat = fmtinfo->fourcc;
> > +     }
> > +
> > +     unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> > +
> > +     return fmtinfo;
> > +}
> > +
> > +static int unicam_try_fmt_meta(struct file *file, void *priv,
> > +                            struct v4l2_format *f)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +
> > +     __unicam_try_fmt_vid(node, &f->fmt.pix);
> > +     return 0;
> > +}
> > +
> > +static int unicam_s_fmt_meta(struct file *file, void *priv,
> > +                          struct v4l2_format *f)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +
> > +     if (vb2_is_busy(&node->buffer_queue))
> > +             return -EBUSY;
> > +
> > +     node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> > +     node->fmt = *f;
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_enum_framesizes(struct file *file, void *fh,
> > +                               struct v4l2_frmsizeenum *fsize)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +     int ret = -EINVAL;
> > +
> > +     if (fsize->index > 0)
> > +             return ret;
> > +
> > +     if (is_image_node(node)) {
> > +             if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > +                                               UNICAM_SD_PAD_SOURCE_IMAGE))
> > +                     return ret;
> > +
> > +             fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> > +             fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> > +             fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> > +             fsize->stepwise.step_width = 1;
> > +             fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> > +             fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> > +             fsize->stepwise.step_height = 1;
> > +     } else {
> > +             if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > +                                               UNICAM_SD_PAD_SOURCE_METADATA))
> > +                     return ret;
> > +
> Isn't this V4L2_FRMSIZE_TYPE_STEPWISE as well ?
>
> > +             fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> > +             fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> > +             fsize->stepwise.step_width = 1;
> > +             fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> > +             fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> > +             fsize->stepwise.step_height = 1;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_log_status(struct file *file, void *fh)
> > +{
> > +     struct unicam_node *node = video_drvdata(file);
> > +     struct unicam_device *unicam = node->dev;
> > +     u32 reg;
> > +
> > +     /* status for sub devices */
> > +     v4l2_device_call_all(&unicam->v4l2_dev, 0, core, log_status);
> > +
> > +     dev_info(unicam->dev, "-----Receiver status-----\n");
> > +     dev_info(unicam->dev, "V4L2 width/height:   %ux%u\n",
> > +              node->fmt.fmt.pix.width, node->fmt.fmt.pix.height);
> > +     dev_info(unicam->dev, "Mediabus format:     %08x\n",
> > +              node->fmtinfo->code);
> > +     dev_info(unicam->dev, "V4L2 format:         %08x\n",
> > +              node->fmt.fmt.pix.pixelformat);
> > +     reg = unicam_reg_read(unicam, UNICAM_IPIPE);
> > +     dev_info(unicam->dev, "Unpacking/packing:   %u / %u\n",
> > +              unicam_get_field(reg, UNICAM_PUM_MASK),
> > +              unicam_get_field(reg, UNICAM_PPM_MASK));
> > +     dev_info(unicam->dev, "----Live data----\n");
> > +     dev_info(unicam->dev, "Programmed stride:   %4u\n",
> > +              unicam_reg_read(unicam, UNICAM_IBLS));
> > +     dev_info(unicam->dev, "Detected resolution: %ux%u\n",
> > +              unicam_reg_read(unicam, UNICAM_IHSTA),
> > +              unicam_reg_read(unicam, UNICAM_IVSTA));
> > +     dev_info(unicam->dev, "Write pointer:       %08x\n",
> > +              unicam_reg_read(unicam, UNICAM_IBWP));
> > +
> > +     return 0;
> > +}
> > +
> > +static int unicam_subscribe_event(struct v4l2_fh *fh,
> > +                               const struct v4l2_event_subscription *sub)
> > +{
> > +     switch (sub->type) {
> > +     case V4L2_EVENT_FRAME_SYNC:
> > +             return v4l2_event_subscribe(fh, sub, 2, NULL);
> > +     default:
> > +             return -EINVAL;
> > +     }
> > +}
> > +
> > +static const struct v4l2_ioctl_ops unicam_ioctl_ops = {
> > +     .vidioc_querycap                = unicam_querycap,
> > +
> > +     .vidioc_enum_fmt_vid_cap        = unicam_enum_fmt_vid,
> > +     .vidioc_g_fmt_vid_cap           = unicam_g_fmt_vid,
> > +     .vidioc_try_fmt_vid_cap         = unicam_try_fmt_vid,
> > +     .vidioc_s_fmt_vid_cap           = unicam_s_fmt_vid,
> > +
> > +     .vidioc_enum_fmt_meta_cap       = unicam_enum_fmt_meta,
> > +     .vidioc_g_fmt_meta_cap          = unicam_g_fmt_meta,
> > +     .vidioc_try_fmt_meta_cap        = unicam_try_fmt_meta,
> > +     .vidioc_s_fmt_meta_cap          = unicam_s_fmt_meta,
> > +
> > +     .vidioc_enum_framesizes         = unicam_enum_framesizes,
> > +
> > +     .vidioc_reqbufs                 = vb2_ioctl_reqbufs,
> > +     .vidioc_create_bufs             = vb2_ioctl_create_bufs,
> > +     .vidioc_prepare_buf             = vb2_ioctl_prepare_buf,
> > +     .vidioc_querybuf                = vb2_ioctl_querybuf,
> > +     .vidioc_qbuf                    = vb2_ioctl_qbuf,
> > +     .vidioc_dqbuf                   = vb2_ioctl_dqbuf,
> > +     .vidioc_expbuf                  = vb2_ioctl_expbuf,
> > +     .vidioc_streamon                = vb2_ioctl_streamon,
> > +     .vidioc_streamoff               = vb2_ioctl_streamoff,
> > +
> > +     .vidioc_log_status              = unicam_log_status,
> > +     .vidioc_subscribe_event         = unicam_subscribe_event,
> > +     .vidioc_unsubscribe_event       = v4l2_event_unsubscribe,
> > +};
> > +
> > +/* unicam capture driver file operations */
> > +static const struct v4l2_file_operations unicam_fops = {
> > +     .owner          = THIS_MODULE,
> > +     .open           = v4l2_fh_open,
> > +     .release        = vb2_fop_release,
> > +     .poll           = vb2_fop_poll,
> > +     .unlocked_ioctl = video_ioctl2,
> > +     .mmap           = vb2_fop_mmap,
> > +};
> > +
> > +static int unicam_video_link_validate(struct media_link *link)
> > +{
> > +     struct video_device *vdev =
> > +             media_entity_to_video_device(link->sink->entity);
> > +     struct v4l2_subdev *sd =
> > +             media_entity_to_v4l2_subdev(link->source->entity);
> > +     struct unicam_node *node = video_get_drvdata(vdev);
> > +     const u32 pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +                   : UNICAM_SD_PAD_SOURCE_METADATA;
> > +     const struct v4l2_mbus_framefmt *format;
> > +     struct v4l2_subdev_state *state;
> > +     int ret = 0;
> > +
> > +     state = v4l2_subdev_lock_and_get_active_state(sd);
> > +
> > +     format = v4l2_subdev_state_get_format(state, pad, 0);
> > +     if (!format) {
> > +             ret = -EINVAL;
> > +             goto out;
> > +     }
> > +
> > +     if (is_image_node(node)) {
> > +             const struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> > +
> > +             if (node->fmtinfo->code != format->code ||
> > +                 fmt->height != format->height ||
> > +                 fmt->width != format->width ||
> > +                 fmt->field != format->field) {
> > +                     dev_dbg(node->dev->dev,
> > +                             "image: (%u x %u) 0x%08x %s != (%u x %u) 0x%08x %s\n",
> > +                             fmt->width, fmt->height, node->fmtinfo->code,
> > +                             v4l2_field_names[fmt->field],
> > +                             format->width, format->height, format->code,
> > +                             v4l2_field_names[format->field]);
> > +                     ret = -EPIPE;
> > +             };
>
> No need for ; here and in the next loop
>
> > +     } else {
> > +             const struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> > +
> > +             if (node->fmtinfo->code != format->code ||
> > +                 fmt->height != format->height ||
> > +                 fmt->width != format->width) {
> > +                     dev_dbg(node->dev->dev,
> > +                             "meta: (%u x %u) 0x%04x != (%u x %u) 0x%04x\n",
> > +                             fmt->width, fmt->height, node->fmtinfo->code,
> > +                             format->width, format->height, format->code);
> > +                     ret = -EPIPE;
> > +             };
> > +     }
> > +
> > +out:
> > +     v4l2_subdev_unlock_state(state);
> > +     return ret;
> > +}
> > +
> > +static const struct media_entity_operations unicam_video_media_ops = {
> > +     .link_validate = unicam_video_link_validate,
> > +};
> > +
> > +static void unicam_node_release(struct video_device *vdev)
> > +{
> > +     struct unicam_node *node = video_get_drvdata(vdev);
> > +
> > +     unicam_put(node->dev);
> > +}
> > +
> > +static void unicam_set_default_format(struct unicam_node *node)
> > +{
> > +     if (is_image_node(node)) {
> > +             struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> > +
> > +             node->fmtinfo = &unicam_image_formats[0];
> > +             node->fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> > +
> > +             v4l2_fill_pix_format(fmt, &unicam_default_image_format);
> > +             fmt->pixelformat = node->fmtinfo->fourcc;
> > +             unicam_calc_image_size_bpl(node->dev, node->fmtinfo, fmt);
> > +     } else {
> > +             struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> > +
> > +             node->fmtinfo = &unicam_meta_formats[0];
> > +             node->fmt.type = V4L2_BUF_TYPE_META_CAPTURE;
> > +
> > +             fmt->dataformat = node->fmtinfo->fourcc;
> > +             fmt->width = unicam_default_meta_format.width;
> > +             fmt->height = unicam_default_meta_format.height;
> > +             unicam_calc_meta_size_bpl(node->dev, node->fmtinfo, fmt);
> > +     }
> > +}
> > +
> > +static int unicam_register_node(struct unicam_device *unicam,
> > +                             enum unicam_node_type type)
> > +{
> > +     const u32 pad_index = type == UNICAM_IMAGE_NODE
> > +                         ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +                         : UNICAM_SD_PAD_SOURCE_METADATA;
> > +     struct unicam_node *node = &unicam->node[type];
> > +     struct video_device *vdev = &node->video_dev;
> > +     struct vb2_queue *q = &node->buffer_queue;
> > +     int ret;
> > +
> > +     node->dev = unicam_get(unicam);
> > +     node->id = type;
> > +
> > +     spin_lock_init(&node->dma_queue_lock);
> > +     mutex_init(&node->lock);
> > +
> > +     INIT_LIST_HEAD(&node->dma_queue);
> > +
> > +     /* Initialize the videobuf2 queue. */
> > +     q->type = type == UNICAM_IMAGE_NODE ? V4L2_BUF_TYPE_VIDEO_CAPTURE
> > +                                         : V4L2_BUF_TYPE_META_CAPTURE;
> > +     q->io_modes = VB2_MMAP | VB2_DMABUF;
> > +     q->drv_priv = node;
> > +     q->ops = &unicam_video_qops;
> > +     q->mem_ops = &vb2_dma_contig_memops;
> > +     q->buf_struct_size = sizeof(struct unicam_buffer);
> > +     q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> > +     q->lock = &node->lock;
> > +     q->min_queued_buffers = 1;
> > +     q->dev = unicam->dev;
> > +
> > +     ret = vb2_queue_init(q);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "vb2_queue_init() failed\n");
> > +             goto err_unicam_put;
> > +     }
> > +
> > +     /* Initialize the video device. */
> > +     vdev->release = unicam_node_release;
> > +     vdev->fops = &unicam_fops;
> > +     vdev->ioctl_ops = &unicam_ioctl_ops;
> > +     vdev->v4l2_dev = &unicam->v4l2_dev;
> > +     vdev->vfl_dir = VFL_DIR_RX;
> > +     vdev->queue = q;
> > +     vdev->lock = &node->lock;
> > +     vdev->device_caps = type == UNICAM_IMAGE_NODE
> > +                       ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_META_CAPTURE;
> > +     vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
> > +     vdev->entity.ops = &unicam_video_media_ops;
> > +
> > +     snprintf(vdev->name, sizeof(vdev->name), "%s-%s", UNICAM_MODULE_NAME,
> > +              type == UNICAM_IMAGE_NODE ? "image" : "embedded");
> > +
> > +     video_set_drvdata(vdev, node);
> > +
> > +     if (type == UNICAM_IMAGE_NODE)
> > +             vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
> > +
> > +     node->pad.flags = MEDIA_PAD_FL_SINK;
> > +
> > +     ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
> > +     if (ret)
> > +             goto err_unicam_put;
> > +
> > +     node->dummy_buf.size = UNICAM_DUMMY_BUF_SIZE;
> > +     node->dummy_buf_cpu_addr = dma_alloc_coherent(unicam->dev,
> > +                                                   node->dummy_buf.size,
> > +                                                   &node->dummy_buf.dma_addr,
> > +                                                   GFP_KERNEL);
> > +     if (!node->dummy_buf_cpu_addr) {
> > +             dev_err(unicam->dev, "Unable to allocate dummy buffer.\n");
> > +             ret = -ENOMEM;
> > +             goto err_entity_cleanup;
> > +     }
> > +
> > +     unicam_set_default_format(node);
> > +
> > +     ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "Unable to register video device %s\n",
> > +                     vdev->name);
> > +             goto err_dma_free;
> > +     }
> > +
> > +     node->registered = true;
> > +
> > +     ret = media_create_pad_link(&unicam->subdev.sd.entity,
> > +                                 pad_index,
> > +                                 &node->video_dev.entity,
> > +                                 0,
> > +                                 MEDIA_LNK_FL_ENABLED |
> > +                                 MEDIA_LNK_FL_IMMUTABLE);
> > +     if (ret) {
> > +             /*
> > +              * No need for cleanup, the caller will unregister the
> > +              * video device, which will drop the reference on the
> > +              * device and trigger the cleanup.
> > +              */
> > +             dev_err(unicam->dev, "Unable to create pad link for %s\n",
> > +                     unicam->sensor.subdev->name);
> > +             return ret;
> > +     }
> > +
> > +     return 0;
> > +
> > +err_dma_free:
> > +     dma_free_coherent(unicam->dev, node->dummy_buf.size,
> > +                       node->dummy_buf_cpu_addr,
> > +                       node->dummy_buf.dma_addr);
> > +err_entity_cleanup:
> > +     media_entity_cleanup(&vdev->entity);
> > +err_unicam_put:
> > +     unicam_put(unicam);
> > +     return ret;
> > +}
> > +
> > +static void unicam_unregister_nodes(struct unicam_device *unicam)
> > +{
> > +     unsigned int i;
> > +
> > +     for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +             struct unicam_node *node = &unicam->node[i];
> > +
> > +             if (node->dummy_buf_cpu_addr)
> > +                     dma_free_coherent(unicam->dev, node->dummy_buf.size,
> > +                                       node->dummy_buf_cpu_addr,
> > +                                       node->dummy_buf.dma_addr);
> > +
> > +             if (node->registered) {
> > +                     video_unregister_device(&node->video_dev);
> > +                     node->registered = false;
> > +             }
> > +     }
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Power management
> > + */
> > +
> > +static int unicam_runtime_resume(struct device *dev)
> > +{
> > +     struct unicam_device *unicam = dev_get_drvdata(dev);
> > +     int ret;
> > +
> > +     ret = clk_set_min_rate(unicam->vpu_clock, UNICAM_MIN_VPU_CLOCK_RATE);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "failed to set up VPU clock\n");
> > +             return ret;
> > +     }
>
> Same question as above, shouldn't this be an 'assigned-clock-rates in
> dts ?
>
> > +
> > +     ret = clk_prepare_enable(unicam->vpu_clock);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "Failed to enable VPU clock: %d\n", ret);
> > +             goto err_vpu_clock;
> > +     }
> > +
> > +     ret = clk_set_rate(unicam->clock, 100 * 1000 * 1000);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "failed to set up CSI clock\n");
> > +             goto err_vpu_prepare;
> > +     }
>
> same question
>
> > +
> > +     ret = clk_prepare_enable(unicam->clock);
> > +     if (ret) {
> > +             dev_err(unicam->dev, "Failed to enable CSI clock: %d\n", ret);
> > +             goto err_vpu_prepare;
>
> Do you need to 'unset' the rate as done for the VPU clock ?
>
> > +     }
> > +
> > +     return 0;
> > +
> > +err_vpu_prepare:
> > +     clk_disable_unprepare(unicam->vpu_clock);
> > +err_vpu_clock:
> > +     if (clk_set_min_rate(unicam->vpu_clock, 0))
> > +             dev_err(unicam->dev, "failed to reset the VPU clock\n");
> > +
> > +     return ret;
> > +}
> > +
> > +static int unicam_runtime_suspend(struct device *dev)
> > +{
> > +     struct unicam_device *unicam = dev_get_drvdata(dev);
> > +
> > +     clk_disable_unprepare(unicam->clock);
>
> (continuing  with the above question: probably not, as the clock is
> not 'unset' neither here)
>
> The rest looks good, nice to see this progressing!
>
> Thanks
>   j
>
<snip>

Dave Stevenson March 5, 2024, 2:56 p.m. UTC | #4

On Mon, 4 Mar 2024 at 19:51, Laurent Pinchart
<[e-mail]> wrote:
>
> Hi Jacopo,
>
> On Mon, Mar 04, 2024 at 06:12:21PM +0100, Jacopo Mondi wrote:
> > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > From: Dave Stevenson <[e-mail]>
> > >
> > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > It is represented as two video device nodes: unicam-image and
> > > unicam-embedded which are connected to an internal subdev (named
> > > unicam-subdev) in order to manage streams routing.
> > >
> > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > > ---
> > > Changes since v5:
> > >
> > > - Move to drivers/media/platform/broadcom/
> > > - Port to the upstream V4L2 streams API
> > > - Rebase on latest metadata API proposal
> > > - Add missing error message
> > > - Drop unneeded documentation block for unicam_isr()
> > > - Drop unneeded dev_dbg() and dev_err() messages
> > > - Drop unneeded streams_mask and fmt checks
> > > - Drop unused unicam_sd_pad_is_sink()
> > > - Drop unneeded includes
> > > - Drop v4l2_ctrl_subscribe_event() call
> > > - Use pm_runtime_resume_and_get()
> > > - Indentation and line wrap fixes
> > > - Let the framework set bus_info
> > > - Use v4l2_fwnode_endpoint_parse()
> > > - Fix media device cleanup
> > > - Drop lane reordering checks
> > > - Fix subdev state locking
> > > - Drop extra debug messages
> > > - Move clock handling to runtime PM handlers
> > > - Reorder functions
> > > - Rename init functions for more clarity
> > > - Initialize runtime PM earlier
> > > - Clarify error messages
> > > - Simplify subdev init with local variable
> > > - Fix subdev cleanup
> > > - Fix typos and indentation
> > > - Don't initialize local variables needlessly
> > > - Simplify num lanes check
> > > - Fix metadata handling in subdev set_fmt
> > > - Drop manual fallback to .s_stream()
> > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > - Simplify unicam_set_default_format()
> > > - Fix default format settings
> > > - Add busy check in unicam_s_fmt_meta()
> > > - Add missing \n at end of format strings
> > > - Fix metadata handling in subdev set_fmt
> > > - Fix locking when starting streaming
> > > - Return buffers from start streaming fails
> > > - Fix format validation for metadata node
> > > - Use video_device_pipeline_{start,stop}() helpers
> > > - Simplify format enumeration
> > > - Drop unset variable
> > > - Update MAINTAINERS entry
> > > - Update to the upstream v4l2_async_nf API
> > > - Update to the latest subdev routing API
> > > - Update to the latest subdev state API
> > > - Move from subdev .init_cfg() to .init_state()
> > > - Update to the latest videobuf2 API
> > > - Fix v4l2_subdev_enable_streams() error check
> > > - Use correct pad for the connected subdev
> > > - Return buffers to vb2 when start streaming fails
> > > - Improve debugging in start streaming handler
> > > - Simplify DMA address management
> > > - Drop comment about bcm2835-camera driver
> > > - Clarify comments that explain min/max sizes
> > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > - Drop unneeded local variables
> > > - Rename image-related constants and functions
> > > - Turn unicam_fmt.metadata_fmt into bool
> > > - Rename unicam_fmt to unicam_format_info
> > > - Rename unicam_format_info variables to fmtinfo
> > > - Rename unicam_node.v_fmt to fmt
> > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > - Make metadata formats line-based
> > > - Validate format on metadata video device
> > > - Add Co-devlopped-by tags
> > >
> > > Changes since v3:
> > >
> > > - Add the vendor prefix for DT name
> > > - Use the reg-names in DT parsing
> > > - Remove MAINTAINERS entry
> > >
> > > Changes since v2:
> > >
> > > - Change code organization
> > > - Remove unused variables
> > > - Correct the fmt_meta functions
> > > - Rewrite the start/stop streaming
> > >   - You can now start the image node alone, but not the metadata one
> > >   - The buffers are allocated per-node
> > >   - only the required stream is started, if the route exists and is
> > >     enabled
> > > - Prefix the macros with UNICAM_ to not have too generic names
> > > - Drop colorspace support
> > >
> > > Changes since v1:
> > >
> > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > ---
> > >  MAINTAINERS                                   |    1 +
> > >  drivers/media/platform/Kconfig                |    1 +
> > >  drivers/media/platform/Makefile               |    1 +
> > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > >  7 files changed, 2891 insertions(+)
> > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
>
> [snip]
>
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > new file mode 100644
> > > index 000000000000..716c89b8a217
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > @@ -0,0 +1,2607 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * BCM283x / BCM271x Unicam Capture Driver
> > > + *
> > > + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> > > + *
> > > + * Dave Stevenson <[e-mail]>
> > > + *
> > > + * Based on TI am437x driver by
> > > + *   Benoit Parrot <[e-mail]>
> > > + *   Lad, Prabhakar <[e-mail]>
> > > + *
> > > + * and TI CAL camera interface driver by
> > > + *    Benoit Parrot <[e-mail]>
> > > + *
> > > + *
> > > + * There are two camera drivers in the kernel for BCM283x - this one and
> > > + * bcm2835-camera (currently in staging).
> > > + *
> > > + * This driver directly controls the Unicam peripheral - there is no
> > > + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> > > + * and writes it into SDRAM. The only potential processing options are to
> > > + * repack Bayer data into an alternate format, and applying windowing. The
> > > + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> > > + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> > > + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> > > + * where the relevant formats are defined, and will automatically configure the
> > > + * repacking as required. Support for windowing may be added later.
> >
> > Does this last paragraph applies ? I see all the supported packed raw
> > format having an 'unpacked_fourcc' associated (all but the 8 bit ones
> > ofc)
>
> Maybe I'm tired, but I'm not sure to understand why you think it may not
> apply.
>
> > > + *
> > > + * It should be possible to connect this driver to any sensor with a suitable
> > > + * output interface and V4L2 subdevice driver.
> > > + */
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/delay.h>
> > > +#include <linux/device.h>
> > > +#include <linux/dma-mapping.h>
> > > +#include <linux/err.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/io.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/pm_runtime.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/videodev2.h>
> > > +
> > > +#include <media/v4l2-async.h>
> > > +#include <media/v4l2-common.h>
> > > +#include <media/v4l2-dev.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-event.h>
> > > +#include <media/v4l2-ioctl.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +#include <media/v4l2-mc.h>
> > > +#include <media/videobuf2-dma-contig.h>
> > > +
> > > +#include "bcm2835-unicam-regs.h"
> > > +
> > > +#define UNICAM_MODULE_NAME         "unicam"
> > > +
> > > +/*
> > > + * Unicam must request a minimum of 250Mhz from the VPU clock.
> > > + * Otherwise the input FIFOs overrun and cause image corruption.
> > > + */
> > > +#define UNICAM_MIN_VPU_CLOCK_RATE  (250 * 1000 * 1000)
> >
> > Shouldn't this be set in DT ?
>
> With assigned-clock-rates ? Then the clock would always run at 250MHz
> (or higher, depending on the rate in the DT), while the driver ensures
> it runs at at least 250MHz only when the device is being used.
>
> > > +
> > > +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> > > +#define UNICAM_DMA_BPL_ALIGNMENT   16
> > > +
> > > +/*
> > > + * The image stride is stored in a 16 bit register, and needs to be aligned to
> > > + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> > > + * constraint on its input, set the image stride alignment to 32 bytes here as
> > > + * well to avoid incompatible configurations.
> > > + */
> > > +#define UNICAM_IMAGE_BPL_ALIGNMENT 32
> > > +#define UNICAM_IMAGE_MAX_BPL               ((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
> > > +
> > > +/*
> > > + * Max width is therefore determined by the max stride divided by the number of
> > > + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> > > + * so adopt a square image for want of anything better.
> > > + */
> > > +#define UNICAM_IMAGE_MIN_WIDTH             16
> > > +#define UNICAM_IMAGE_MIN_HEIGHT            16
> > > +#define UNICAM_IMAGE_MAX_WIDTH             (UNICAM_IMAGE_MAX_BPL / 4)
> > > +#define UNICAM_IMAGE_MAX_HEIGHT            UNICAM_IMAGE_MAX_WIDTH
> > > +
> > > +/*
> > > + * There's no intrinsic limits on the width and height for embedded dat. Use

s/dat/data

> > > + * the same maximum values as for the image, to avoid overflows in the image
> > > + * size computation.
> > > + */
> > > +#define UNICAM_META_MIN_WIDTH              1
> > > +#define UNICAM_META_MIN_HEIGHT             1
> > > +#define UNICAM_META_MAX_WIDTH              UNICAM_IMAGE_MAX_WIDTH
> > > +#define UNICAM_META_MAX_HEIGHT             UNICAM_IMAGE_MAX_HEIGHT
> > > +
> > > +/*
> > > + * Size of the dummy buffer. Can be any size really, but the DMA
> > > + * allocation works in units of page sizes.
> > > + */
> > > +#define UNICAM_DUMMY_BUF_SIZE              PAGE_SIZE
> > > +
> > > +#define UNICAM_SD_PAD_SINK         0
> > > +#define UNICAM_SD_PAD_SOURCE_IMAGE 1
> > > +#define UNICAM_SD_PAD_SOURCE_METADATA      2
> > > +#define UNICAM_SD_NUM_PADS         (1 + UNICAM_SD_PAD_SOURCE_METADATA)
> >
> > How about an enum then ?
>
> OK.
>
> > > +
> > > +enum unicam_node_type {
> > > +   UNICAM_IMAGE_NODE,
> > > +   UNICAM_METADATA_NODE,
> > > +   UNICAM_MAX_NODES
> > > +};
> > > +
> > > +/*
> > > + * struct unicam_format_info - Unicam media bus format information
> > > + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> > > + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> > > + * out to 16bpp. 0 if n/a.
> > > + * @code: V4L2 media bus format code.
> > > + * @depth: Bits per pixel as delivered from the source.
> > > + * @csi_dt: CSI data type.
> > > + * @metadata_fmt: This format only applies to the metadata pad.
> > > + */
> > > +struct unicam_format_info {
> > > +   u32     fourcc;
> > > +   u32     unpacked_fourcc;
> > > +   u32     code;
> > > +   u8      depth;
> > > +   u8      csi_dt;
> > > +   bool    metadata_fmt;
> > > +};
> > > +
> > > +struct unicam_buffer {
> > > +   struct vb2_v4l2_buffer vb;
> > > +   struct list_head list;
> > > +   dma_addr_t dma_addr;
> > > +   unsigned int size;
> > > +};
> > > +
> > > +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> > > +{
> > > +   return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> > > +}
> > > +
> > > +struct unicam_node {
> > > +   bool registered;
> > > +   bool streaming;
> > > +   unsigned int id;
> > > +
> > > +   /* Pointer to the current v4l2_buffer */
> > > +   struct unicam_buffer *cur_frm;
> > > +   /* Pointer to the next v4l2_buffer */
> > > +   struct unicam_buffer *next_frm;
> > > +   /* video capture */
> > > +   const struct unicam_format_info *fmtinfo;
> > > +   /* Used to store current pixel format */
> > > +   struct v4l2_format fmt;
> > > +   /* Buffer queue used in video-buf */
> > > +   struct vb2_queue buffer_queue;
> > > +   /* Queue of filled frames */
> > > +   struct list_head dma_queue;
> > > +   /* IRQ lock for DMA queue */
> > > +   spinlock_t dma_queue_lock;
> > > +   /* lock used to access this structure */
> > > +   struct mutex lock;
> > > +   /* Identifies video device for this channel */
> > > +   struct video_device video_dev;
> > > +   /* Pointer to the parent handle */
> > > +   struct unicam_device *dev;
> > > +   struct media_pad pad;
> > > +   /*
> > > +    * Dummy buffer intended to be used by unicam
> > > +    * if we have no other queued buffers to swap to.
> > > +    */
> > > +   struct unicam_buffer dummy_buf;
> > > +   void *dummy_buf_cpu_addr;
> > > +};
> > > +
> > > +struct unicam_device {
> > > +   struct kref kref;
> > > +
> > > +   /* peripheral base address */
> > > +   void __iomem *base;
> > > +   /* clock gating base address */
> > > +   void __iomem *clk_gate_base;
> >
> > Is the clock gating part of unicam or should this be expressed as a
> > clock provide and be referenced in DT through a phandle ?
>
> No idea :-) Dave, Naush ?

Answered in my previous reply.

> > > +   /* lp clock handle */
> > > +   struct clk *clock;
> > > +   /* vpu clock handle */
> > > +   struct clk *vpu_clock;
> > > +   /* V4l2 device */
> > > +   struct v4l2_device v4l2_dev;
> > > +   struct media_device mdev;
> > > +
> > > +   /* parent device */
> > > +   struct device *dev;
> > > +   /* subdevice async Notifier */
> >
> > s/Notifier/notifier
> >
> > > +   struct v4l2_async_notifier notifier;
> > > +   unsigned int sequence;
> > > +
> > > +   /* Sensor node */
> > > +   struct {
> > > +           struct v4l2_subdev *subdev;
> > > +           struct media_pad *pad;
> > > +   } sensor;
> > > +
> > > +   /* Internal subdev */
> > > +   struct {
> > > +           struct v4l2_subdev sd;
> > > +           struct media_pad pads[UNICAM_SD_NUM_PADS];
> > > +           bool streaming;
> > > +   } subdev;
> > > +
> > > +   enum v4l2_mbus_type bus_type;
> > > +   /*
> > > +    * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> > > +    * bus.mipi_csi1.strobe for CCP2.
> > > +    */
> > > +   unsigned int bus_flags;
> > > +   unsigned int max_data_lanes;
> > > +   unsigned int active_data_lanes;
> > > +
> > > +   struct media_pipeline pipe;
> > > +
> > > +   struct unicam_node node[UNICAM_MAX_NODES];
> > > +};
> > > +
> > > +static inline struct unicam_device *
> > > +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> > > +{
> > > +   return container_of(notifier, struct unicam_device, notifier);
> > > +}
> > > +
> > > +static inline struct unicam_device *
> >
> > I thought using inline is disouraged as the compiler knows what to do
>
> For this kind of wrapper around container_of() the kernel usually has an
> explicit inline keyword. I can drop it if needed.
>
> > > +sd_to_unicam_device(struct v4l2_subdev *sd)
> > > +{
> > > +   return container_of(sd, struct unicam_device, subdev.sd);
> >
> > You can also use container_of_const() if you need it
>
> There's no const subdev anywhere.
>
> > > +}
> > > +
> > > +static void unicam_release(struct kref *kref)
> > > +{
> > > +   struct unicam_device *unicam =
> > > +           container_of(kref, struct unicam_device, kref);
> > > +
> > > +   if (unicam->mdev.dev)
> > > +           media_device_cleanup(&unicam->mdev);
> > > +
> > > +   kfree(unicam);
> > > +}
> > > +
> > > +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> > > +{
> > > +   kref_get(&unicam->kref);
> > > +   return unicam;
> > > +}
> > > +
> > > +static void unicam_put(struct unicam_device *unicam)
> > > +{
> > > +   kref_put(&unicam->kref, unicam_release);
> > > +}
> > > +
> >
> > Does this handle a bit more gracefully the pesky lifetime management
> > issue in v4l2 ?
>
> That's supposed to be the idea :-)
>
> > > +/* -----------------------------------------------------------------------------
> > > + * Misc helper functions
> > > + */
> > > +
> > > +static inline bool unicam_sd_pad_is_source(u32 pad)
> > > +{
> > > +   /* Camera RX has 1 sink pad, and N source pads */
> > > +   return pad != UNICAM_SD_PAD_SINK;
> > > +}
> > > +
> > > +static inline bool is_metadata_node(struct unicam_node *node)
> > > +{
> > > +   return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> > > +}
> > > +
> > > +static inline bool is_image_node(struct unicam_node *node)
> > > +{
> > > +   return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> > > +}
>
> [snip]
>
> > > +/* -----------------------------------------------------------------------------
> > > + * Videobuf2 queue operations
> > > + */
> > > +
> > > +static int unicam_queue_setup(struct vb2_queue *vq,
> > > +                         unsigned int *nbuffers,
> > > +                         unsigned int *nplanes,
> > > +                         unsigned int sizes[],
> > > +                         struct device *alloc_devs[])
> > > +{
> > > +   struct unicam_node *node = vb2_get_drv_priv(vq);
> > > +   u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > > +            : node->fmt.fmt.meta.buffersize;
> > > +
> > > +   if (vq->num_buffers + *nbuffers < 3)
> >
> > Why 3 ? Are these dummies ?
>
> This may be a remnant of old code. Dave, Naush, any comment ?

I suspect this is legacy.
Originally the driver would only release the buffer at the frame end
when it had a new one to switch to. Naush updated with the dummy
buffer so in theory you can run with 1 buffer, but this min number of
buffers probably didn't get reduced.
Then again it may have been a misunderstanding of the framework, as
struct vb2_queue min_buffers_needed should set the minimum.

> > > +           *nbuffers = 3 - vq->num_buffers;
> > > +
> > > +   if (*nplanes) {
> > > +           if (sizes[0] < size) {
> > > +                   dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> > > +                           sizes[0], size);
> > > +                   return -EINVAL;
> > > +           }
> > > +           size = sizes[0];
> > > +   }
> > > +
> > > +   *nplanes = 1;
> > > +   sizes[0] = size;
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static int unicam_buffer_prepare(struct vb2_buffer *vb)
> > > +{
> > > +   struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > > +   struct unicam_buffer *buf = to_unicam_buffer(vb);
> > > +   u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > > +            : node->fmt.fmt.meta.buffersize;
> > > +
> > > +   if (vb2_plane_size(vb, 0) < size) {
> > > +           dev_dbg(node->dev->dev,
> > > +                   "data will not fit into plane (%lu < %u)\n",
> > > +                   vb2_plane_size(vb, 0), size);
> > > +           return -EINVAL;
> > > +   }
> > > +
> > > +   buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> > > +   buf->size = size;
> > > +
> > > +   vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static void unicam_return_buffers(struct unicam_node *node,
> > > +                             enum vb2_buffer_state state)
> > > +{
> > > +   struct unicam_buffer *buf, *tmp;
> > > +
> > > +   list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> > > +           list_del(&buf->list);
> > > +           vb2_buffer_done(&buf->vb.vb2_buf, state);
> > > +   }
> > > +
> > > +   if (node->cur_frm)
> > > +           vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> > > +                           state);
> > > +   if (node->next_frm && node->cur_frm != node->next_frm)
> > > +           vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> > > +                           state);
> > > +
> > > +   node->cur_frm = NULL;
> > > +   node->next_frm = NULL;
> > > +}
> > > +
> > > +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> > > +{
> > > +   struct unicam_node *node = vb2_get_drv_priv(vq);
> > > +   struct unicam_device *unicam = node->dev;
> > > +   struct v4l2_subdev_state *state;
> > > +   struct unicam_buffer *buf;
> > > +   unsigned long flags;
> > > +   int ret;
> > > +   u32 pad, stream;
> > > +   u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                                        : UNICAM_SD_PAD_SOURCE_METADATA;
> > > +
> > > +   /* Look for the route for the given pad and stream. */
> > > +   state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> > > +   ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > > +                                               remote_pad, 0,
> > > +                                               &pad, &stream);
> > > +   v4l2_subdev_unlock_state(state);
> > > +
> > > +   if (ret)
> > > +           goto err_return_buffers;
> > > +
> > > +   dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> > > +           unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> > > +           is_metadata_node(node) ? "metadata" : "image");
> > > +
> > > +   /* The metadata node can't be started alone. */
> > > +   if (is_metadata_node(node)) {
> > > +           if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> >
> > Does it mean the metadata node has to be started second, or should
> > this be made a nop and the metadata node gets started once the image
> > node is started too ? I'm fine with the constraint of having the
> > metadata node being started second fwiw
>
> I think it would be nice to change this indeed. Dave, Naush, any
> objection ?

See previous email.

> > > +                   dev_err(unicam->dev,
> > > +                           "Can't start metadata without image\n");
> > > +                   ret = -EINVAL;
> > > +                   goto err_return_buffers;
> > > +           }
> > > +
> > > +           spin_lock_irqsave(&node->dma_queue_lock, flags);
> > > +           buf = list_first_entry(&node->dma_queue,
> > > +                                  struct unicam_buffer, list);
> > > +           dev_dbg(unicam->dev, "buffer %p\n", buf);
> >
> > Is this useful ?
>
> Probably not much. I'll drop it.
>
> > > +           node->cur_frm = buf;
> > > +           node->next_frm = buf;
> > > +           list_del(&buf->list);
> > > +           spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > > +
> > > +           unicam_start_metadata(unicam, buf);
> > > +           node->streaming = true;
> > > +           return 0;
> > > +   }
> > > +
> > > +   ret = pm_runtime_resume_and_get(unicam->dev);
> > > +   if (ret < 0) {
> > > +           dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> > > +           goto err_return_buffers;
> > > +   }
> > > +
> > > +   ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> > > +   if (ret < 0) {
> > > +           dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> >
> > Isn't this an err ?
>
> The main cause of failure is a pipeline validation error, triggered by
> userspace, hence the debug level.
>
> > > +           goto err_pm_put;
> > > +   }
> > > +
> > > +   spin_lock_irqsave(&node->dma_queue_lock, flags);
> > > +   buf = list_first_entry(&node->dma_queue,
> > > +                          struct unicam_buffer, list);
> > > +   dev_dbg(unicam->dev, "buffer %p\n", buf);
> > > +   node->cur_frm = buf;
> > > +   node->next_frm = buf;
> > > +   list_del(&buf->list);
> > > +   spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > > +
> > > +   unicam_start_rx(unicam, buf);
> > > +
> > > +   ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> >
> > A bit confused by the API here, shouldn't we also do this for embedded
> > data ?
>
> Not here, as the two streams go over different pads, but likely above,
> as part of the change you proposed regarding stream start on the
> metadata device. I'll wait for Dave and Naush to reply, and I'll rework
> this function.

I haven't read enough on the streams API, or what this implementation
looks like.

There's no sensible way for a sensor to start embedded or other
metadata without image data, so starting the image node would seem to
be the main trigger for anything. I'm also assuming we don't support
enabling additional multiplexed streams once the pipeline is already
running, so that would seem to determine some of the sequencing.

  Dave

> > > +   if (ret < 0) {
> > > +           dev_err(unicam->dev, "stream on failed in subdev\n");
> > > +           goto error_pipeline;
> > > +   }
> > > +
> > > +   node->streaming = true;
> > > +
> > > +   return 0;
> > > +
> > > +error_pipeline:
> > > +   video_device_pipeline_stop(&node->video_dev);
> > > +err_pm_put:
> > > +   pm_runtime_put_sync(unicam->dev);
> > > +err_return_buffers:
> > > +   unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> > > +   return ret;
> > > +}
> > > +
> > > +static void unicam_stop_streaming(struct vb2_queue *vq)
> > > +{
> > > +   struct unicam_node *node = vb2_get_drv_priv(vq);
> > > +   struct unicam_device *unicam = node->dev;
> > > +   u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                                              : UNICAM_SD_PAD_SOURCE_METADATA;
> > > +
> > > +   node->streaming = false;
> > > +
> > > +   v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> > > +                               BIT(0));
> > > +
> > > +   /* We can stream only with the image node. */
> > > +   if (is_metadata_node(node)) {
> > > +           /*
> > > +            * Allow the hardware to spin in the dummy buffer.
> > > +            * This is only really needed if the embedded data pad is
> > > +            * disabled before the image pad.
> > > +            */
> > > +           unicam_wr_dma_addr(node, &node->dummy_buf);
> > > +           goto dequeue_buffers;
> > > +   }
> > > +
> > > +   unicam_disable(unicam);
> > > +
> > > +   video_device_pipeline_stop(&node->video_dev);
> > > +   pm_runtime_put(unicam->dev);
> > > +
> > > +dequeue_buffers:
> > > +   /* Clear all queued buffers for the node */
> > > +   unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> > > +}
> > > +
> > > +static void unicam_buffer_queue(struct vb2_buffer *vb)
> > > +{
> > > +   struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > > +   struct unicam_buffer *buf = to_unicam_buffer(vb);
> > > +
> > > +   spin_lock_irq(&node->dma_queue_lock);
> > > +   list_add_tail(&buf->list, &node->dma_queue);
> > > +   spin_unlock_irq(&node->dma_queue_lock);
> > > +}
> > > +
> > > +static const struct vb2_ops unicam_video_qops = {
> > > +   .queue_setup            = unicam_queue_setup,
> > > +   .wait_prepare           = vb2_ops_wait_prepare,
> > > +   .wait_finish            = vb2_ops_wait_finish,
> > > +   .buf_prepare            = unicam_buffer_prepare,
> > > +   .start_streaming        = unicam_start_streaming,
> > > +   .stop_streaming         = unicam_stop_streaming,
> > > +   .buf_queue              = unicam_buffer_queue,
> > > +};
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + *  V4L2 video device operations
> > > + */
> > > +
> > > +static int unicam_querycap(struct file *file, void *priv,
> > > +                      struct v4l2_capability *cap)
> > > +{
> > > +   strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> > > +   strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> > > +
> > > +   cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> > > +                          struct v4l2_fmtdesc *f)
> > > +{
> > > +   unsigned int index;
> > > +   unsigned int i;
> > > +
> > > +   for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> > > +           if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> > > +                   continue;
> > > +
> > > +           if (index == f->index) {
> > > +                   f->pixelformat = unicam_image_formats[i].fourcc;
> > > +                   return 0;
> > > +           }
> > > +
> > > +           index++;
> > > +
> > > +           if (!unicam_image_formats[i].unpacked_fourcc)
> > > +                   continue;
> > > +
> > > +           if (index == f->index) {
> > > +                   f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> > > +                   return 0;
> > > +           }
> > > +
> > > +           index++;
> > > +   }
> > > +
> > > +   return -EINVAL;
> > > +}
> > > +
> > > +static int unicam_g_fmt_vid(struct file *file, void *priv,
> > > +                       struct v4l2_format *f)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +
> > > +   *f = node->fmt;
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static const struct unicam_format_info *
> > > +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> > > +{
> > > +   const struct unicam_format_info *fmtinfo;
> > > +
> > > +   /*
> > > +    * Default to the first format if the requested pixel format code isn't
> > > +    * supported.
> > > +    */
> > > +   fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> > > +                                          UNICAM_SD_PAD_SOURCE_IMAGE);
> > > +   if (!fmtinfo) {
> > > +           fmtinfo = &unicam_image_formats[0];
> > > +           pix->pixelformat = fmtinfo->fourcc;
> > > +   }
> > > +
> > > +   unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> > > +
> > > +   if (pix->field == V4L2_FIELD_ANY)
> > > +           pix->field = V4L2_FIELD_NONE;
> > > +
> > > +   return fmtinfo;
> > > +}
> > > +
> > > +static int unicam_try_fmt_vid(struct file *file, void *priv,
> > > +                         struct v4l2_format *f)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +
> > > +   __unicam_try_fmt_vid(node, &f->fmt.pix);
> > > +   return 0;
> > > +}
> > > +
> > > +static int unicam_s_fmt_vid(struct file *file, void *priv,
> > > +                       struct v4l2_format *f)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +
> > > +   if (vb2_is_busy(&node->buffer_queue))
> > > +           return -EBUSY;
> > > +
> > > +   node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> > > +   node->fmt = *f;
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> > > +                           struct v4l2_fmtdesc *f)
> > > +{
> > > +   unsigned int i, index;
> > > +
> > > +   for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> > > +           if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
> >
> > Do we want to allow mbus_code filtering for metadata ? There's a
> > 1-to-1 relationship between mbus codes and pixel formats
>
> Is there a reason not to allow it ? I think it's good for the API to be
> consistent. Generally speaking, a CSI-2 receiver could receive
> META_CSI2_10 and convert it to the META_8 pixel format. Filtering as a
> concept thus make sense I think.
>
> > > +                   continue;
> > > +           if (!unicam_meta_formats[i].metadata_fmt)
> > > +                   continue;
> >
> > How can this be false if we're iterating on unicam_meta_formats[] ?
>
> True. I'll drop the metadata_fmt field.
>
> > > +
> > > +           if (index == f->index) {
> > > +                   f->pixelformat = unicam_meta_formats[i].fourcc;
> > > +                   f->type = V4L2_BUF_TYPE_META_CAPTURE;
> > > +                   return 0;
> > > +           }
> > > +           index++;
> > > +   }
> > > +
> > > +   return -EINVAL;
> > > +}
> > > +
> > > +static int unicam_g_fmt_meta(struct file *file, void *priv,
> > > +                        struct v4l2_format *f)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +
> > > +   f->fmt.meta = node->fmt.fmt.meta;
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static const struct unicam_format_info *
> > > +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> > > +{
> > > +   const struct unicam_format_info *fmtinfo;
> > > +
> > > +   /*
> > > +    * Default to the first format if the requested pixel format code isn't
> > > +    * supported.
> > > +    */
> > > +   fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> > > +                                          UNICAM_SD_PAD_SOURCE_METADATA);
> > > +   if (!fmtinfo) {
> > > +           fmtinfo = &unicam_meta_formats[0];
> > > +           meta->dataformat = fmtinfo->fourcc;
> > > +   }
> > > +
> > > +   unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> > > +
> > > +   return fmtinfo;
> > > +}
> > > +
> > > +static int unicam_try_fmt_meta(struct file *file, void *priv,
> > > +                          struct v4l2_format *f)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +
> > > +   __unicam_try_fmt_vid(node, &f->fmt.pix);
> > > +   return 0;
> > > +}
> > > +
> > > +static int unicam_s_fmt_meta(struct file *file, void *priv,
> > > +                        struct v4l2_format *f)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +
> > > +   if (vb2_is_busy(&node->buffer_queue))
> > > +           return -EBUSY;
> > > +
> > > +   node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> > > +   node->fmt = *f;
> > > +
> > > +   return 0;
> > > +}
> > > +
> > > +static int unicam_enum_framesizes(struct file *file, void *fh,
> > > +                             struct v4l2_frmsizeenum *fsize)
> > > +{
> > > +   struct unicam_node *node = video_drvdata(file);
> > > +   int ret = -EINVAL;
> > > +
> > > +   if (fsize->index > 0)
> > > +           return ret;
> > > +
> > > +   if (is_image_node(node)) {
> > > +           if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > > +                                             UNICAM_SD_PAD_SOURCE_IMAGE))
> > > +                   return ret;
> > > +
> > > +           fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> > > +           fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> > > +           fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> > > +           fsize->stepwise.step_width = 1;
> > > +           fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> > > +           fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> > > +           fsize->stepwise.step_height = 1;
> > > +   } else {
> > > +           if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > > +                                             UNICAM_SD_PAD_SOURCE_METADATA))
> > > +                   return ret;
> > > +
> >
> > Isn't this V4L2_FRMSIZE_TYPE_STEPWISE as well ?
>
> Indeed, I'll fix that.
>
> > > +           fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> > > +           fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> > > +           fsize->stepwise.step_width = 1;
> > > +           fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> > > +           fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> > > +           fsize->stepwise.step_height = 1;
> > > +   }
> > > +
> > > +   return 0;
> > > +}
>
> [snip]
>
> --
> Regards,
>
> Laurent Pinchart

Laurent Pinchart March 16, 2024, 10:36 p.m. UTC | #5

On Tue, Mar 05, 2024 at 02:15:51PM +0000, Dave Stevenson wrote:
> Hi Laurent and Jacopo.
> 
> I'd started this reply before Laurent's follow up - I'll respond to
> that in a moment.
> 
> On Mon, 4 Mar 2024 at 17:12, Jacopo Mondi <[e-mail]> wrote:
> >
> > Hi Laurent
> >
> > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > From: Dave Stevenson <[e-mail]>
> > >
> > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > It is represented as two video device nodes: unicam-image and
> > > unicam-embedded which are connected to an internal subdev (named
> > > unicam-subdev) in order to manage streams routing.
> > >
> > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > > ---
> > > Changes since v5:
> > >
> > > - Move to drivers/media/platform/broadcom/
> > > - Port to the upstream V4L2 streams API
> > > - Rebase on latest metadata API proposal
> > > - Add missing error message
> > > - Drop unneeded documentation block for unicam_isr()
> > > - Drop unneeded dev_dbg() and dev_err() messages
> > > - Drop unneeded streams_mask and fmt checks
> > > - Drop unused unicam_sd_pad_is_sink()
> > > - Drop unneeded includes
> > > - Drop v4l2_ctrl_subscribe_event() call
> > > - Use pm_runtime_resume_and_get()
> > > - Indentation and line wrap fixes
> > > - Let the framework set bus_info
> > > - Use v4l2_fwnode_endpoint_parse()
> > > - Fix media device cleanup
> > > - Drop lane reordering checks
> > > - Fix subdev state locking
> > > - Drop extra debug messages
> > > - Move clock handling to runtime PM handlers
> > > - Reorder functions
> > > - Rename init functions for more clarity
> > > - Initialize runtime PM earlier
> > > - Clarify error messages
> > > - Simplify subdev init with local variable
> > > - Fix subdev cleanup
> > > - Fix typos and indentation
> > > - Don't initialize local variables needlessly
> > > - Simplify num lanes check
> > > - Fix metadata handling in subdev set_fmt
> > > - Drop manual fallback to .s_stream()
> > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > - Simplify unicam_set_default_format()
> > > - Fix default format settings
> > > - Add busy check in unicam_s_fmt_meta()
> > > - Add missing \n at end of format strings
> > > - Fix metadata handling in subdev set_fmt
> > > - Fix locking when starting streaming
> > > - Return buffers from start streaming fails
> > > - Fix format validation for metadata node
> > > - Use video_device_pipeline_{start,stop}() helpers
> > > - Simplify format enumeration
> > > - Drop unset variable
> > > - Update MAINTAINERS entry
> > > - Update to the upstream v4l2_async_nf API
> > > - Update to the latest subdev routing API
> > > - Update to the latest subdev state API
> > > - Move from subdev .init_cfg() to .init_state()
> > > - Update to the latest videobuf2 API
> > > - Fix v4l2_subdev_enable_streams() error check
> > > - Use correct pad for the connected subdev
> > > - Return buffers to vb2 when start streaming fails
> > > - Improve debugging in start streaming handler
> > > - Simplify DMA address management
> > > - Drop comment about bcm2835-camera driver
> > > - Clarify comments that explain min/max sizes
> > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > - Drop unneeded local variables
> > > - Rename image-related constants and functions
> > > - Turn unicam_fmt.metadata_fmt into bool
> > > - Rename unicam_fmt to unicam_format_info
> > > - Rename unicam_format_info variables to fmtinfo
> > > - Rename unicam_node.v_fmt to fmt
> > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > - Make metadata formats line-based
> > > - Validate format on metadata video device
> > > - Add Co-devlopped-by tags
> > >
> > > Changes since v3:
> > >
> > > - Add the vendor prefix for DT name
> > > - Use the reg-names in DT parsing
> > > - Remove MAINTAINERS entry
> > >
> > > Changes since v2:
> > >
> > > - Change code organization
> > > - Remove unused variables
> > > - Correct the fmt_meta functions
> > > - Rewrite the start/stop streaming
> > >   - You can now start the image node alone, but not the metadata one
> > >   - The buffers are allocated per-node
> > >   - only the required stream is started, if the route exists and is
> > >     enabled
> > > - Prefix the macros with UNICAM_ to not have too generic names
> > > - Drop colorspace support
> > >
> > > Changes since v1:
> > >
> > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > ---
> > >  MAINTAINERS                                   |    1 +
> > >  drivers/media/platform/Kconfig                |    1 +
> > >  drivers/media/platform/Makefile               |    1 +
> > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > >  7 files changed, 2891 insertions(+)
> > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index e50a59654e6e..cc350729f467 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -4002,6 +4002,7 @@ M:      Raspberry Pi Kernel Maintenance <[e-mail]>
> > >  L:   [e-mail]
> > >  S:   Maintained
> > >  F:   Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > > +F:   drivers/media/platform/bcm2835/
> > >
> > >  BROADCOM BCM47XX MIPS ARCHITECTURE
> > >  M:   Hauke Mehrtens <[e-mail]>
> > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > index 91e54215de3a..2d79bfc68c15 100644
> > > --- a/drivers/media/platform/Kconfig
> > > +++ b/drivers/media/platform/Kconfig
> > > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> > >  source "drivers/media/platform/amphion/Kconfig"
> > >  source "drivers/media/platform/aspeed/Kconfig"
> > >  source "drivers/media/platform/atmel/Kconfig"
> > > +source "drivers/media/platform/broadcom/Kconfig"
> > >  source "drivers/media/platform/cadence/Kconfig"
> > >  source "drivers/media/platform/chips-media/Kconfig"
> > >  source "drivers/media/platform/intel/Kconfig"
> > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > > index 3296ec1ebe16..da17301f7439 100644
> > > --- a/drivers/media/platform/Makefile
> > > +++ b/drivers/media/platform/Makefile
> > > @@ -10,6 +10,7 @@ obj-y += amlogic/
> > >  obj-y += amphion/
> > >  obj-y += aspeed/
> > >  obj-y += atmel/
> > > +obj-y += broadcom/
> > >  obj-y += cadence/
> > >  obj-y += chips-media/
> > >  obj-y += intel/
> > > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > > new file mode 100644
> > > index 000000000000..cc2c9afcc948
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/Kconfig
> > > @@ -0,0 +1,23 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +config VIDEO_BCM2835_UNICAM
> > > +     tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > > +     depends on ARCH_BCM2835 || COMPILE_TEST
> > > +     depends on PM
> > > +     depends on VIDEO_DEV
> > > +     select MEDIA_CONTROLLER
> > > +     select V4L2_FWNODE
> > > +     select VIDEO_V4L2_SUBDEV_API
> > > +     select VIDEOBUF2_DMA_CONTIG
> > > +     help
> > > +       Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > > +       This is a V4L2 driver that controls the CSI-2 receiver directly,
> > > +       independently from the VC4 firmware.
> > > +
> > > +       This driver is mutually exclusive with the use of bcm2835-camera. The
> > > +       firmware will disable all access to the peripheral from within the
> > > +       firmware if it finds a DT node using it, and bcm2835-camera will
> > > +       therefore fail to probe.
> > > +
> > > +       To compile this driver as a module, choose M here. The module will be
> > > +       called bcm2835-unicam.
> > > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > > new file mode 100644
> > > index 000000000000..03d2045aba2e
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/Makefile
> > > @@ -0,0 +1,3 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > new file mode 100644
> > > index 000000000000..84775fd2fac5
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > @@ -0,0 +1,255 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +
> > > +/*
> > > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> > > + * Dave Stevenson <[e-mail]>
> > > + */
> > > +
> > > +#ifndef VC4_REGS_UNICAM_H
> > > +#define VC4_REGS_UNICAM_H
> > > +
> > > +#include <linux/bits.h>
> > > +
> > > +/*
> > > + * The following values are taken from files found within the code drop
> > > + * made by Broadcom for the BCM21553 Graphics Driver, predominantly in
> > > + * brcm_usrlib/dag/vmcsx/vcinclude/hardware_vc4.h.
> > > + * They have been modified to be only the register offset.
> > > + */
> > > +#define UNICAM_CTRL          0x000
> > > +#define UNICAM_STA           0x004
> > > +#define UNICAM_ANA           0x008
> > > +#define UNICAM_PRI           0x00c
> > > +#define UNICAM_CLK           0x010
> > > +#define UNICAM_CLT           0x014
> > > +#define UNICAM_DAT0          0x018
> > > +#define UNICAM_DAT1          0x01c
> > > +#define UNICAM_DAT2          0x020
> > > +#define UNICAM_DAT3          0x024
> > > +#define UNICAM_DLT           0x028
> > > +#define UNICAM_CMP0          0x02c
> > > +#define UNICAM_CMP1          0x030
> > > +#define UNICAM_CAP0          0x034
> > > +#define UNICAM_CAP1          0x038
> > > +#define UNICAM_ICTL          0x100
> > > +#define UNICAM_ISTA          0x104
> > > +#define UNICAM_IDI0          0x108
> > > +#define UNICAM_IPIPE         0x10c
> > > +#define UNICAM_IBSA0         0x110
> > > +#define UNICAM_IBEA0         0x114
> > > +#define UNICAM_IBLS          0x118
> > > +#define UNICAM_IBWP          0x11c
> > > +#define UNICAM_IHWIN         0x120
> > > +#define UNICAM_IHSTA         0x124
> > > +#define UNICAM_IVWIN         0x128
> > > +#define UNICAM_IVSTA         0x12c
> > > +#define UNICAM_ICC           0x130
> > > +#define UNICAM_ICS           0x134
> > > +#define UNICAM_IDC           0x138
> > > +#define UNICAM_IDPO          0x13c
> > > +#define UNICAM_IDCA          0x140
> > > +#define UNICAM_IDCD          0x144
> > > +#define UNICAM_IDS           0x148
> > > +#define UNICAM_DCS           0x200
> > > +#define UNICAM_DBSA0         0x204
> > > +#define UNICAM_DBEA0         0x208
> > > +#define UNICAM_DBWP          0x20c
> > > +#define UNICAM_DBCTL         0x300
> > > +#define UNICAM_IBSA1         0x304
> > > +#define UNICAM_IBEA1         0x308
> > > +#define UNICAM_IDI1          0x30c
> > > +#define UNICAM_DBSA1         0x310
> > > +#define UNICAM_DBEA1         0x314
> > > +#define UNICAM_MISC          0x400
> > > +
> > > +/*
> > > + * The following bitmasks are from the kernel released by Broadcom
> > > + * for Android - https://android.googlesource.com/kernel/bcm/
> > > + * The Rhea, Hawaii, and Java chips all contain the same VideoCore4
> > > + * Unicam block as BCM2835, as defined in eg
> > > + * arch/arm/mach-rhea/include/mach/rdb_A0/brcm_rdb_cam.h and similar.
> > > + * Values reworked to use the kernel BIT and GENMASK macros.
> > > + *
> > > + * Some of the bit mnenomics have been amended to match the datasheet.
> > > + */
> > > +/* UNICAM_CTRL Register */
> > > +#define UNICAM_CPE           BIT(0)
> > > +#define UNICAM_MEM           BIT(1)
> > > +#define UNICAM_CPR           BIT(2)
> > > +#define UNICAM_CPM_MASK              GENMASK(3, 3)
> > > +#define UNICAM_CPM_CSI2              0
> > > +#define UNICAM_CPM_CCP2              1
> > > +#define UNICAM_SOE           BIT(4)
> > > +#define UNICAM_DCM_MASK              GENMASK(5, 5)
> > > +#define UNICAM_DCM_STROBE    0
> > > +#define UNICAM_DCM_DATA              1
> > > +#define UNICAM_SLS           BIT(6)
> > > +#define UNICAM_PFT_MASK              GENMASK(11, 8)
> > > +#define UNICAM_OET_MASK              GENMASK(20, 12)
> > > +
> > > +/* UNICAM_STA Register */
> > > +#define UNICAM_SYN           BIT(0)
> > > +#define UNICAM_CS            BIT(1)
> > > +#define UNICAM_SBE           BIT(2)
> > > +#define UNICAM_PBE           BIT(3)
> > > +#define UNICAM_HOE           BIT(4)
> > > +#define UNICAM_PLE           BIT(5)
> > > +#define UNICAM_SSC           BIT(6)
> > > +#define UNICAM_CRCE          BIT(7)
> > > +#define UNICAM_OES           BIT(8)
> > > +#define UNICAM_IFO           BIT(9)
> > > +#define UNICAM_OFO           BIT(10)
> > > +#define UNICAM_BFO           BIT(11)
> > > +#define UNICAM_DL            BIT(12)
> > > +#define UNICAM_PS            BIT(13)
> > > +#define UNICAM_IS            BIT(14)
> > > +#define UNICAM_PI0           BIT(15)
> > > +#define UNICAM_PI1           BIT(16)
> > > +#define UNICAM_FSI_S         BIT(17)
> > > +#define UNICAM_FEI_S         BIT(18)
> > > +#define UNICAM_LCI_S         BIT(19)
> > > +#define UNICAM_BUF0_RDY              BIT(20)
> > > +#define UNICAM_BUF0_NO               BIT(21)
> > > +#define UNICAM_BUF1_RDY              BIT(22)
> > > +#define UNICAM_BUF1_NO               BIT(23)
> > > +#define UNICAM_DI            BIT(24)
> > > +
> > > +#define UNICAM_STA_MASK_ALL \
> > > +             (UNICAM_DL | \
> > > +             UNICAM_SBE | \
> > > +             UNICAM_PBE | \
> > > +             UNICAM_HOE | \
> > > +             UNICAM_PLE | \
> > > +             UNICAM_SSC | \
> > > +             UNICAM_CRCE | \
> > > +             UNICAM_IFO | \
> > > +             UNICAM_OFO | \
> > > +             UNICAM_PS | \
> > > +             UNICAM_PI0 | \
> > > +             UNICAM_PI1)
> > > +
> > > +/* UNICAM_ANA Register */
> > > +#define UNICAM_APD           BIT(0)
> > > +#define UNICAM_BPD           BIT(1)
> > > +#define UNICAM_AR            BIT(2)
> > > +#define UNICAM_DDL           BIT(3)
> > > +#define UNICAM_CTATADJ_MASK  GENMASK(7, 4)
> > > +#define UNICAM_PTATADJ_MASK  GENMASK(11, 8)
> > > +
> > > +/* UNICAM_PRI Register */
> > > +#define UNICAM_PE            BIT(0)
> > > +#define UNICAM_PT_MASK               GENMASK(2, 1)
> > > +#define UNICAM_NP_MASK               GENMASK(7, 4)
> > > +#define UNICAM_PP_MASK               GENMASK(11, 8)
> > > +#define UNICAM_BS_MASK               GENMASK(15, 12)
> > > +#define UNICAM_BL_MASK               GENMASK(17, 16)
> > > +
> > > +/* UNICAM_CLK Register */
> > > +#define UNICAM_CLE           BIT(0)
> > > +#define UNICAM_CLPD          BIT(1)
> > > +#define UNICAM_CLLPE         BIT(2)
> > > +#define UNICAM_CLHSE         BIT(3)
> > > +#define UNICAM_CLTRE         BIT(4)
> > > +#define UNICAM_CLAC_MASK     GENMASK(8, 5)
> > > +#define UNICAM_CLSTE         BIT(29)
> > > +
> > > +/* UNICAM_CLT Register */
> > > +#define UNICAM_CLT1_MASK     GENMASK(7, 0)
> > > +#define UNICAM_CLT2_MASK     GENMASK(15, 8)
> > > +
> > > +/* UNICAM_DATn Registers */
> > > +#define UNICAM_DLE           BIT(0)
> > > +#define UNICAM_DLPD          BIT(1)
> > > +#define UNICAM_DLLPE         BIT(2)
> > > +#define UNICAM_DLHSE         BIT(3)
> > > +#define UNICAM_DLTRE         BIT(4)
> > > +#define UNICAM_DLSM          BIT(5)
> > > +#define UNICAM_DLFO          BIT(28)
> > > +#define UNICAM_DLSTE         BIT(29)
> > > +
> > > +#define UNICAM_DAT_MASK_ALL  (UNICAM_DLSTE | UNICAM_DLFO)
> > > +
> > > +/* UNICAM_DLT Register */
> > > +#define UNICAM_DLT1_MASK     GENMASK(7, 0)
> > > +#define UNICAM_DLT2_MASK     GENMASK(15, 8)
> > > +#define UNICAM_DLT3_MASK     GENMASK(23, 16)
> > > +
> > > +/* UNICAM_ICTL Register */
> > > +#define UNICAM_FSIE          BIT(0)
> > > +#define UNICAM_FEIE          BIT(1)
> > > +#define UNICAM_IBOB          BIT(2)
> > > +#define UNICAM_FCM           BIT(3)
> > > +#define UNICAM_TFC           BIT(4)
> > > +#define UNICAM_LIP_MASK              GENMASK(6, 5)
> > > +#define UNICAM_LCIE_MASK     GENMASK(28, 16)
> > > +
> > > +/* UNICAM_IDI0/1 Register */
> > > +#define UNICAM_ID0_MASK              GENMASK(7, 0)
> > > +#define UNICAM_ID1_MASK              GENMASK(15, 8)
> > > +#define UNICAM_ID2_MASK              GENMASK(23, 16)
> > > +#define UNICAM_ID3_MASK              GENMASK(31, 24)
> > > +
> > > +/* UNICAM_ISTA Register */
> > > +#define UNICAM_FSI           BIT(0)
> > > +#define UNICAM_FEI           BIT(1)
> > > +#define UNICAM_LCI           BIT(2)
> > > +
> > > +#define UNICAM_ISTA_MASK_ALL (UNICAM_FSI | UNICAM_FEI | UNICAM_LCI)
> > > +
> > > +/* UNICAM_IPIPE Register */
> > > +#define UNICAM_PUM_MASK              GENMASK(2, 0)
> > > +/* Unpacking modes */
> > > +#define UNICAM_PUM_NONE              0
> > > +#define UNICAM_PUM_UNPACK6   1
> > > +#define UNICAM_PUM_UNPACK7   2
> > > +#define UNICAM_PUM_UNPACK8   3
> > > +#define UNICAM_PUM_UNPACK10  4
> > > +#define UNICAM_PUM_UNPACK12  5
> > > +#define UNICAM_PUM_UNPACK14  6
> > > +#define UNICAM_PUM_UNPACK16  7
> > > +#define UNICAM_DDM_MASK              GENMASK(6, 3)
> > > +#define UNICAM_PPM_MASK              GENMASK(9, 7)
> > > +/* Packing modes */
> > > +#define UNICAM_PPM_NONE              0
> > > +#define UNICAM_PPM_PACK8     1
> > > +#define UNICAM_PPM_PACK10    2
> > > +#define UNICAM_PPM_PACK12    3
> > > +#define UNICAM_PPM_PACK14    4
> > > +#define UNICAM_PPM_PACK16    5
> > > +#define UNICAM_DEM_MASK              GENMASK(11, 10)
> > > +#define UNICAM_DEBL_MASK     GENMASK(14, 12)
> > > +#define UNICAM_ICM_MASK              GENMASK(16, 15)
> > > +#define UNICAM_IDM_MASK              GENMASK(17, 17)
> > > +
> > > +/* UNICAM_ICC Register */
> > > +#define UNICAM_ICFL_MASK     GENMASK(4, 0)
> > > +#define UNICAM_ICFH_MASK     GENMASK(9, 5)
> > > +#define UNICAM_ICST_MASK     GENMASK(12, 10)
> > > +#define UNICAM_ICLT_MASK     GENMASK(15, 13)
> > > +#define UNICAM_ICLL_MASK     GENMASK(31, 16)
> > > +
> > > +/* UNICAM_DCS Register */
> > > +#define UNICAM_DIE           BIT(0)
> > > +#define UNICAM_DIM           BIT(1)
> > > +#define UNICAM_DBOB          BIT(3)
> > > +#define UNICAM_FDE           BIT(4)
> > > +#define UNICAM_LDP           BIT(5)
> > > +#define UNICAM_EDL_MASK              GENMASK(15, 8)
> > > +
> > > +/* UNICAM_DBCTL Register */
> > > +#define UNICAM_DBEN          BIT(0)
> > > +#define UNICAM_BUF0_IE               BIT(1)
> > > +#define UNICAM_BUF1_IE               BIT(2)
> > > +
> > > +/* UNICAM_CMP[0,1] register */
> > > +#define UNICAM_PCE           BIT(31)
> > > +#define UNICAM_GI            BIT(9)
> > > +#define UNICAM_CPH           BIT(8)
> > > +#define UNICAM_PCVC_MASK     GENMASK(7, 6)
> > > +#define UNICAM_PCDT_MASK     GENMASK(5, 0)
> > > +
> > > +/* UNICAM_MISC register */
> > > +#define UNICAM_FL0           BIT(6)
> > > +#define UNICAM_FL1           BIT(9)
> > > +
> > > +#endif
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > new file mode 100644
> > > index 000000000000..716c89b8a217
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > @@ -0,0 +1,2607 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * BCM283x / BCM271x Unicam Capture Driver
> > > + *
> > > + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> > > + *
> > > + * Dave Stevenson <[e-mail]>
> > > + *
> > > + * Based on TI am437x driver by
> > > + *   Benoit Parrot <[e-mail]>
> > > + *   Lad, Prabhakar <[e-mail]>
> > > + *
> > > + * and TI CAL camera interface driver by
> > > + *    Benoit Parrot <[e-mail]>
> > > + *
> > > + *
> > > + * There are two camera drivers in the kernel for BCM283x - this one and
> > > + * bcm2835-camera (currently in staging).
> > > + *
> > > + * This driver directly controls the Unicam peripheral - there is no
> > > + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> > > + * and writes it into SDRAM. The only potential processing options are to
> > > + * repack Bayer data into an alternate format, and applying windowing. The
> > > + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> > > + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> > > + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> > > + * where the relevant formats are defined, and will automatically configure the
> > > + * repacking as required. Support for windowing may be added later.
> >
> > Does this last paragraph applies ? I see all the supported packed raw
> > format having an 'unpacked_fourcc' associated (all but the 8 bit ones
> > ofc)
> 
> The penultimate sentence ("The driver will add both formats where the
> relevant formats are defined") can be dropped as you've dropped the
> video-node centric mode of operation, therefore all formats (whether
> packed or unpacked) are always advertised.
> 
> The rest of the paragraph still applies - if you request a
> V4L2_PIX_FMT_SxxxxBB (not packed) format, then it the incoming data
> will be unpacked for you.
> 
> > > + *
> > > + * It should be possible to connect this driver to any sensor with a suitable
> > > + * output interface and V4L2 subdevice driver.
> > > + */
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/delay.h>
> > > +#include <linux/device.h>
> > > +#include <linux/dma-mapping.h>
> > > +#include <linux/err.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/io.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/pm_runtime.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/videodev2.h>
> > > +
> > > +#include <media/v4l2-async.h>
> > > +#include <media/v4l2-common.h>
> > > +#include <media/v4l2-dev.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-event.h>
> > > +#include <media/v4l2-ioctl.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +#include <media/v4l2-mc.h>
> > > +#include <media/videobuf2-dma-contig.h>
> > > +
> > > +#include "bcm2835-unicam-regs.h"
> > > +
> > > +#define UNICAM_MODULE_NAME           "unicam"
> > > +
> > > +/*
> > > + * Unicam must request a minimum of 250Mhz from the VPU clock.
> > > + * Otherwise the input FIFOs overrun and cause image corruption.
> > > + */
> > > +#define UNICAM_MIN_VPU_CLOCK_RATE    (250 * 1000 * 1000)
> >
> > Shouldn't this be set in DT ?
> >
> > > +
> > > +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> > > +#define UNICAM_DMA_BPL_ALIGNMENT     16
> > > +
> > > +/*
> > > + * The image stride is stored in a 16 bit register, and needs to be aligned to
> > > + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> > > + * constraint on its input, set the image stride alignment to 32 bytes here as
> > > + * well to avoid incompatible configurations.
> > > + */
> > > +#define UNICAM_IMAGE_BPL_ALIGNMENT   32
> > > +#define UNICAM_IMAGE_MAX_BPL         ((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
> > > +
> > > +/*
> > > + * Max width is therefore determined by the max stride divided by the number of
> > > + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> > > + * so adopt a square image for want of anything better.
> > > + */
> > > +#define UNICAM_IMAGE_MIN_WIDTH               16
> > > +#define UNICAM_IMAGE_MIN_HEIGHT              16
> > > +#define UNICAM_IMAGE_MAX_WIDTH               (UNICAM_IMAGE_MAX_BPL / 4)
> > > +#define UNICAM_IMAGE_MAX_HEIGHT              UNICAM_IMAGE_MAX_WIDTH
> > > +
> > > +/*
> > > + * There's no intrinsic limits on the width and height for embedded dat. Use
> > > + * the same maximum values as for the image, to avoid overflows in the image
> > > + * size computation.
> > > + */
> > > +#define UNICAM_META_MIN_WIDTH                1
> > > +#define UNICAM_META_MIN_HEIGHT               1
> > > +#define UNICAM_META_MAX_WIDTH                UNICAM_IMAGE_MAX_WIDTH
> > > +#define UNICAM_META_MAX_HEIGHT               UNICAM_IMAGE_MAX_HEIGHT
> > > +
> > > +/*
> > > + * Size of the dummy buffer. Can be any size really, but the DMA
> > > + * allocation works in units of page sizes.
> > > + */
> > > +#define UNICAM_DUMMY_BUF_SIZE                PAGE_SIZE
> > > +
> > > +#define UNICAM_SD_PAD_SINK           0
> > > +#define UNICAM_SD_PAD_SOURCE_IMAGE   1
> > > +#define UNICAM_SD_PAD_SOURCE_METADATA        2
> > > +#define UNICAM_SD_NUM_PADS           (1 + UNICAM_SD_PAD_SOURCE_METADATA)
> >
> > How about an enum then ?
> >
> > > +
> > > +enum unicam_node_type {
> > > +     UNICAM_IMAGE_NODE,
> > > +     UNICAM_METADATA_NODE,
> > > +     UNICAM_MAX_NODES
> > > +};
> > > +
> > > +/*
> > > + * struct unicam_format_info - Unicam media bus format information
> > > + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> > > + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> > > + * out to 16bpp. 0 if n/a.
> > > + * @code: V4L2 media bus format code.
> > > + * @depth: Bits per pixel as delivered from the source.
> > > + * @csi_dt: CSI data type.
> > > + * @metadata_fmt: This format only applies to the metadata pad.
> > > + */
> > > +struct unicam_format_info {
> > > +     u32     fourcc;
> > > +     u32     unpacked_fourcc;
> > > +     u32     code;
> > > +     u8      depth;
> > > +     u8      csi_dt;
> > > +     bool    metadata_fmt;
> > > +};
> > > +
> > > +struct unicam_buffer {
> > > +     struct vb2_v4l2_buffer vb;
> > > +     struct list_head list;
> > > +     dma_addr_t dma_addr;
> > > +     unsigned int size;
> > > +};
> > > +
> > > +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> > > +{
> > > +     return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> > > +}
> > > +
> > > +struct unicam_node {
> > > +     bool registered;
> > > +     bool streaming;
> > > +     unsigned int id;
> > > +
> > > +     /* Pointer to the current v4l2_buffer */
> > > +     struct unicam_buffer *cur_frm;
> > > +     /* Pointer to the next v4l2_buffer */
> > > +     struct unicam_buffer *next_frm;
> > > +     /* video capture */
> > > +     const struct unicam_format_info *fmtinfo;
> > > +     /* Used to store current pixel format */
> > > +     struct v4l2_format fmt;
> > > +     /* Buffer queue used in video-buf */
> > > +     struct vb2_queue buffer_queue;
> > > +     /* Queue of filled frames */
> > > +     struct list_head dma_queue;
> > > +     /* IRQ lock for DMA queue */
> > > +     spinlock_t dma_queue_lock;
> > > +     /* lock used to access this structure */
> > > +     struct mutex lock;
> > > +     /* Identifies video device for this channel */
> > > +     struct video_device video_dev;
> > > +     /* Pointer to the parent handle */
> > > +     struct unicam_device *dev;
> > > +     struct media_pad pad;
> > > +     /*
> > > +      * Dummy buffer intended to be used by unicam
> > > +      * if we have no other queued buffers to swap to.
> > > +      */
> > > +     struct unicam_buffer dummy_buf;
> > > +     void *dummy_buf_cpu_addr;
> > > +};
> > > +
> > > +struct unicam_device {
> > > +     struct kref kref;
> > > +
> > > +     /* peripheral base address */
> > > +     void __iomem *base;
> > > +     /* clock gating base address */
> > > +     void __iomem *clk_gate_base;
> >
> > Is the clock gating part of unicam or should this be expressed as a
> > clock provide and be referenced in DT through a phandle ?
> 
> Covered in previous reviews and accepted as part of unicam.
> https://patchwork.kernel.org/project/linux-media/patch/fae3d2[e-mail]/
> 
> > > +     /* lp clock handle */
> > > +     struct clk *clock;
> > > +     /* vpu clock handle */
> > > +     struct clk *vpu_clock;
> > > +     /* V4l2 device */
> > > +     struct v4l2_device v4l2_dev;
> > > +     struct media_device mdev;
> > > +
> > > +     /* parent device */
> > > +     struct device *dev;
> > > +     /* subdevice async Notifier */
> >
> > s/Notifier/notifier
> >
> > > +     struct v4l2_async_notifier notifier;
> > > +     unsigned int sequence;
> > > +
> > > +     /* Sensor node */
> > > +     struct {
> > > +             struct v4l2_subdev *subdev;
> > > +             struct media_pad *pad;
> > > +     } sensor;
> > > +
> > > +     /* Internal subdev */
> > > +     struct {
> > > +             struct v4l2_subdev sd;
> > > +             struct media_pad pads[UNICAM_SD_NUM_PADS];
> > > +             bool streaming;
> > > +     } subdev;
> > > +
> > > +     enum v4l2_mbus_type bus_type;
> > > +     /*
> > > +      * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> > > +      * bus.mipi_csi1.strobe for CCP2.
> > > +      */
> > > +     unsigned int bus_flags;
> > > +     unsigned int max_data_lanes;
> > > +     unsigned int active_data_lanes;
> > > +
> > > +     struct media_pipeline pipe;
> > > +
> > > +     struct unicam_node node[UNICAM_MAX_NODES];
> > > +};
> > > +
> > > +static inline struct unicam_device *
> > > +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> > > +{
> > > +     return container_of(notifier, struct unicam_device, notifier);
> > > +}
> > > +
> > > +static inline struct unicam_device *
> >
> > I thought using inline is disouraged as the compiler knows what to do
> >
> > > +sd_to_unicam_device(struct v4l2_subdev *sd)
> > > +{
> > > +     return container_of(sd, struct unicam_device, subdev.sd);
> >
> > You can also use container_of_const() if you need it
> >
> > > +}
> > > +
> > > +static void unicam_release(struct kref *kref)
> > > +{
> > > +     struct unicam_device *unicam =
> > > +             container_of(kref, struct unicam_device, kref);
> > > +
> > > +     if (unicam->mdev.dev)
> > > +             media_device_cleanup(&unicam->mdev);
> > > +
> > > +     kfree(unicam);
> > > +}
> > > +
> > > +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> > > +{
> > > +     kref_get(&unicam->kref);
> > > +     return unicam;
> > > +}
> > > +
> > > +static void unicam_put(struct unicam_device *unicam)
> > > +{
> > > +     kref_put(&unicam->kref, unicam_release);
> > > +}
> > > +
> >
> > Does this handle a bit more gracefully the pesky lifetime management
> > issue in v4l2 ?
> >
> > > +/* -----------------------------------------------------------------------------
> > > + * Misc helper functions
> > > + */
> > > +
> > > +static inline bool unicam_sd_pad_is_source(u32 pad)
> > > +{
> > > +     /* Camera RX has 1 sink pad, and N source pads */
> > > +     return pad != UNICAM_SD_PAD_SINK;
> > > +}
> > > +
> > > +static inline bool is_metadata_node(struct unicam_node *node)
> > > +{
> > > +     return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> > > +}
> > > +
> > > +static inline bool is_image_node(struct unicam_node *node)
> > > +{
> > > +     return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> > > +}
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + * Format data table and helper functions
> > > + */
> > > +
> > > +static const struct v4l2_mbus_framefmt unicam_default_image_format = {
> > > +     .width = 640,
> > > +     .height = 480,
> > > +     .code = MEDIA_BUS_FMT_UYVY8_1X16,
> > > +     .field = V4L2_FIELD_NONE,
> > > +     .colorspace = V4L2_COLORSPACE_SRGB,
> > > +     .ycbcr_enc = V4L2_YCBCR_ENC_601,
> > > +     .quantization = V4L2_QUANTIZATION_LIM_RANGE,
> > > +     .xfer_func = V4L2_XFER_FUNC_SRGB,
> > > +     .flags = 0,
> > > +};
> > > +
> > > +static const struct v4l2_mbus_framefmt unicam_default_meta_format = {
> > > +     .width = 640,
> > > +     .height = 2,
> > > +     .code = MEDIA_BUS_FMT_META_8,
> > > +     .field = V4L2_FIELD_NONE,
> > > +};
> > > +
> > > +static const struct unicam_format_info unicam_image_formats[] = {
> > > +     /* YUV Formats */
> > > +     {
> > > +             .fourcc         = V4L2_PIX_FMT_YUYV,
> > > +             .code           = MEDIA_BUS_FMT_YUYV8_1X16,
> > > +             .depth          = 16,
> > > +             .csi_dt         = 0x1e,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_UYVY,
> > > +             .code           = MEDIA_BUS_FMT_UYVY8_1X16,
> > > +             .depth          = 16,
> > > +             .csi_dt         = 0x1e,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_YVYU,
> > > +             .code           = MEDIA_BUS_FMT_YVYU8_1X16,
> > > +             .depth          = 16,
> > > +             .csi_dt         = 0x1e,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_VYUY,
> > > +             .code           = MEDIA_BUS_FMT_VYUY8_1X16,
> > > +             .depth          = 16,
> > > +             .csi_dt         = 0x1e,
> > > +     }, {
> > > +     /* RGB Formats */
> > > +             .fourcc         = V4L2_PIX_FMT_RGB565, /* gggbbbbb rrrrrggg */
> > > +             .code           = MEDIA_BUS_FMT_RGB565_1X16,
> > > +             .depth          = 16,
> > > +             .csi_dt         = 0x22,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_RGB24, /* rgb */
> > > +             .code           = MEDIA_BUS_FMT_RGB888_1X24,
> > > +             .depth          = 24,
> > > +             .csi_dt         = 0x24,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_BGR24, /* bgr */
> > > +             .code           = MEDIA_BUS_FMT_BGR888_1X24,
> > > +             .depth          = 24,
> > > +             .csi_dt         = 0x24,
> > > +     }, {
> > > +     /* Bayer Formats */
> > > +             .fourcc         = V4L2_PIX_FMT_SBGGR8,
> > > +             .code           = MEDIA_BUS_FMT_SBGGR8_1X8,
> > > +             .depth          = 8,
> > > +             .csi_dt         = 0x2a,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGBRG8,
> > > +             .code           = MEDIA_BUS_FMT_SGBRG8_1X8,
> > > +             .depth          = 8,
> > > +             .csi_dt         = 0x2a,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGRBG8,
> > > +             .code           = MEDIA_BUS_FMT_SGRBG8_1X8,
> > > +             .depth          = 8,
> > > +             .csi_dt         = 0x2a,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SRGGB8,
> > > +             .code           = MEDIA_BUS_FMT_SRGGB8_1X8,
> > > +             .depth          = 8,
> > > +             .csi_dt         = 0x2a,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SBGGR10P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SBGGR10,
> > > +             .code           = MEDIA_BUS_FMT_SBGGR10_1X10,
> > > +             .depth          = 10,
> > > +             .csi_dt         = 0x2b,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGBRG10P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SGBRG10,
> > > +             .code           = MEDIA_BUS_FMT_SGBRG10_1X10,
> > > +             .depth          = 10,
> > > +             .csi_dt         = 0x2b,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGRBG10P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SGRBG10,
> > > +             .code           = MEDIA_BUS_FMT_SGRBG10_1X10,
> > > +             .depth          = 10,
> > > +             .csi_dt         = 0x2b,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SRGGB10P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SRGGB10,
> > > +             .code           = MEDIA_BUS_FMT_SRGGB10_1X10,
> > > +             .depth          = 10,
> > > +             .csi_dt         = 0x2b,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SBGGR12P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SBGGR12,
> > > +             .code           = MEDIA_BUS_FMT_SBGGR12_1X12,
> > > +             .depth          = 12,
> > > +             .csi_dt         = 0x2c,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGBRG12P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SGBRG12,
> > > +             .code           = MEDIA_BUS_FMT_SGBRG12_1X12,
> > > +             .depth          = 12,
> > > +             .csi_dt         = 0x2c,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGRBG12P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SGRBG12,
> > > +             .code           = MEDIA_BUS_FMT_SGRBG12_1X12,
> > > +             .depth          = 12,
> > > +             .csi_dt         = 0x2c,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SRGGB12P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SRGGB12,
> > > +             .code           = MEDIA_BUS_FMT_SRGGB12_1X12,
> > > +             .depth          = 12,
> > > +             .csi_dt         = 0x2c,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SBGGR14P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SBGGR14,
> > > +             .code           = MEDIA_BUS_FMT_SBGGR14_1X14,
> > > +             .depth          = 14,
> > > +             .csi_dt         = 0x2d,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGBRG14P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SGBRG14,
> > > +             .code           = MEDIA_BUS_FMT_SGBRG14_1X14,
> > > +             .depth          = 14,
> > > +             .csi_dt         = 0x2d,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SGRBG14P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SGRBG14,
> > > +             .code           = MEDIA_BUS_FMT_SGRBG14_1X14,
> > > +             .depth          = 14,
> > > +             .csi_dt         = 0x2d,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_SRGGB14P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_SRGGB14,
> > > +             .code           = MEDIA_BUS_FMT_SRGGB14_1X14,
> > > +             .depth          = 14,
> > > +             .csi_dt         = 0x2d,
> > > +     }, {
> > > +     /* 16 bit Bayer formats could be supported. */
> > > +
> > > +     /* Greyscale formats */
> > > +             .fourcc         = V4L2_PIX_FMT_GREY,
> > > +             .code           = MEDIA_BUS_FMT_Y8_1X8,
> > > +             .depth          = 8,
> > > +             .csi_dt         = 0x2a,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_Y10P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_Y10,
> > > +             .code           = MEDIA_BUS_FMT_Y10_1X10,
> > > +             .depth          = 10,
> > > +             .csi_dt         = 0x2b,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_Y12P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_Y12,
> > > +             .code           = MEDIA_BUS_FMT_Y12_1X12,
> > > +             .depth          = 12,
> > > +             .csi_dt         = 0x2c,
> > > +     }, {
> > > +             .fourcc         = V4L2_PIX_FMT_Y14P,
> > > +             .unpacked_fourcc = V4L2_PIX_FMT_Y14,
> > > +             .code           = MEDIA_BUS_FMT_Y14_1X14,
> > > +             .depth          = 14,
> > > +             .csi_dt         = 0x2d,
> > > +     },
> > > +};
> > > +
> > > +static const struct unicam_format_info unicam_meta_formats[] = {
> > > +     {
> > > +             .fourcc         = V4L2_META_FMT_GENERIC_8,
> > > +             .code           = MEDIA_BUS_FMT_META_8,
> > > +             .depth          = 8,
> > > +             .metadata_fmt   = true,
> > > +     }, {
> > > +             .fourcc         = V4L2_META_FMT_GENERIC_CSI2_10,
> > > +             .code           = MEDIA_BUS_FMT_META_10,
> > > +             .depth          = 10,
> > > +             .metadata_fmt   = true,
> > > +     }, {
> > > +             .fourcc         = V4L2_META_FMT_GENERIC_CSI2_12,
> > > +             .code           = MEDIA_BUS_FMT_META_12,
> > > +             .depth          = 12,
> > > +             .metadata_fmt   = true,
> > > +     }, {
> > > +             .fourcc         = V4L2_META_FMT_GENERIC_CSI2_14,
> > > +             .code           = MEDIA_BUS_FMT_META_14,
> > > +             .depth          = 14,
> > > +             .metadata_fmt   = true,
> > > +     },
> > > +};
> > > +
> > > +/* Format setup functions */
> > > +static const struct unicam_format_info *
> > > +unicam_find_format_by_code(u32 code, u32 pad)
> > > +{
> > > +     const struct unicam_format_info *formats;
> > > +     unsigned int num_formats;
> > > +     unsigned int i;
> > > +
> > > +     if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > > +             formats = unicam_image_formats;
> > > +             num_formats = ARRAY_SIZE(unicam_image_formats);
> > > +     } else {
> > > +             formats = unicam_meta_formats;
> > > +             num_formats = ARRAY_SIZE(unicam_meta_formats);
> > > +     }
> > > +
> > > +     for (i = 0; i < num_formats; i++) {
> > > +             if (formats[i].code == code)
> > > +                     return &formats[i];
> > > +     }
> > > +
> > > +     return NULL;
> > > +}
> > > +
> > > +static const struct unicam_format_info *
> > > +unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
> > > +{
> > > +     const struct unicam_format_info *formats;
> > > +     unsigned int num_formats;
> > > +     unsigned int i;
> > > +
> > > +     if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > > +             formats = unicam_image_formats;
> > > +             num_formats = ARRAY_SIZE(unicam_image_formats);
> > > +     } else {
> > > +             formats = unicam_meta_formats;
> > > +             num_formats = ARRAY_SIZE(unicam_meta_formats);
> > > +     }
> > > +
> > > +     for (i = 0; i < num_formats; ++i) {
> > > +             if (formats[i].fourcc == fourcc)
> > > +                     return &formats[i];
> > > +     }
> > > +
> > > +     return NULL;
> > > +}
> > > +
> > > +static void unicam_calc_image_size_bpl(struct unicam_device *unicam,
> > > +                                    const struct unicam_format_info *fmtinfo,
> > > +                                    struct v4l2_pix_format *pix)
> > > +{
> > > +     u32 min_bpl;
> > > +
> > > +     v4l_bound_align_image(&pix->width, UNICAM_IMAGE_MIN_WIDTH,
> > > +                           UNICAM_IMAGE_MAX_WIDTH, 2,
> > > +                           &pix->height, UNICAM_IMAGE_MIN_HEIGHT,
> > > +                           UNICAM_IMAGE_MAX_HEIGHT, 0, 0);
> > > +
> > > +     /* Unpacking always goes to 16bpp */
> > > +     if (pix->pixelformat == fmtinfo->unpacked_fourcc)
> > > +             min_bpl = pix->width * 2;
> > > +     else
> > > +             min_bpl = pix->width * fmtinfo->depth / 8;
> > > +     min_bpl = ALIGN(min_bpl, UNICAM_IMAGE_BPL_ALIGNMENT);
> > > +
> > > +     pix->bytesperline = ALIGN(pix->bytesperline, UNICAM_IMAGE_BPL_ALIGNMENT);
> > > +     pix->bytesperline = clamp_t(unsigned int, pix->bytesperline, min_bpl,
> > > +                                 UNICAM_IMAGE_MAX_BPL);
> > > +
> > > +     pix->sizeimage = pix->height * pix->bytesperline;
> > > +}
> > > +
> > > +static void unicam_calc_meta_size_bpl(struct unicam_device *unicam,
> > > +                                   const struct unicam_format_info *fmtinfo,
> > > +                                   struct v4l2_meta_format *meta)
> > > +{
> > > +     v4l_bound_align_image(&meta->width, UNICAM_META_MIN_WIDTH,
> > > +                           UNICAM_META_MAX_WIDTH, 0,
> > > +                           &meta->height, UNICAM_META_MIN_HEIGHT,
> > > +                           UNICAM_META_MAX_HEIGHT, 0, 0);
> > > +
> > > +     meta->bytesperline = ALIGN(meta->width * fmtinfo->depth / 8,
> > > +                                UNICAM_DMA_BPL_ALIGNMENT);
> > > +     meta->buffersize = meta->height * meta->bytesperline;
> > > +}
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + * Hardware handling
> > > + */
> > > +
> >
> > As this has been used for years in BSP driver, I won't go in detail in
> > the HW handling functions
> >
> > > +static inline void unicam_clk_write(struct unicam_device *unicam, u32 val)
> > > +{
> > > +     /* Pass the CM_PASSWORD along with the value. */
> > > +     writel(val | 0x5a000000, unicam->clk_gate_base);
> > > +}
> > > +
> > > +static inline u32 unicam_reg_read(struct unicam_device *unicam, u32 offset)
> > > +{
> > > +     return readl(unicam->base + offset);
> > > +}
> > > +
> > > +static inline void unicam_reg_write(struct unicam_device *unicam, u32 offset, u32 val)
> > > +{
> > > +     writel(val, unicam->base + offset);
> > > +}
> > > +
> > > +static inline int unicam_get_field(u32 value, u32 mask)
> > > +{
> > > +     return (value & mask) >> __ffs(mask);
> > > +}
> > > +
> > > +static inline void unicam_set_field(u32 *valp, u32 field, u32 mask)
> > > +{
> > > +     u32 val = *valp;
> > > +
> > > +     val &= ~mask;
> > > +     val |= (field << __ffs(mask)) & mask;
> > > +     *valp = val;
> > > +}
> > > +
> > > +static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offset,
> > > +                                       u32 field, u32 mask)
> > > +{
> > > +     u32 val = unicam_reg_read(unicam, offset);
> > > +
> > > +     unicam_set_field(&val, field, mask);
> > > +     unicam_reg_write(unicam, offset, val);
> > > +}
> > > +
> > > +static void unicam_wr_dma_addr(struct unicam_node *node,
> > > +                            struct unicam_buffer *buf)
> > > +{
> > > +     dma_addr_t endaddr = buf->dma_addr + buf->size;
> > > +
> > > +     if (node->id == UNICAM_IMAGE_NODE) {
> > > +             unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
> > > +             unicam_reg_write(node->dev, UNICAM_IBEA0, endaddr);
> > > +     } else {
> > > +             unicam_reg_write(node->dev, UNICAM_DBSA0, buf->dma_addr);
> > > +             unicam_reg_write(node->dev, UNICAM_DBEA0, endaddr);
> > > +     }
> > > +}
> > > +
> > > +static unsigned int unicam_get_lines_done(struct unicam_device *unicam)
> > > +{
> > > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +     unsigned int stride = node->fmt.fmt.pix.bytesperline;
> > > +     struct unicam_buffer *frm = node->cur_frm;
> > > +     dma_addr_t cur_addr;
> > > +
> > > +     if (!frm)
> > > +             return 0;
> > > +
> > > +     cur_addr = unicam_reg_read(unicam, UNICAM_IBWP);
> > > +     return (unsigned int)(cur_addr - frm->dma_addr) / stride;
> > > +}
> > > +
> > > +static void unicam_schedule_next_buffer(struct unicam_node *node)
> > > +{
> > > +     struct unicam_buffer *buf;
> > > +
> > > +     buf = list_first_entry(&node->dma_queue, struct unicam_buffer, list);
> > > +     node->next_frm = buf;
> > > +     list_del(&buf->list);
> > > +
> > > +     unicam_wr_dma_addr(node, buf);
> > > +}
> > > +
> > > +static void unicam_schedule_dummy_buffer(struct unicam_node *node)
> > > +{
> > > +     int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
> > > +
> > > +     dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
> > > +
> > > +     unicam_wr_dma_addr(node, &node->dummy_buf);
> > > +
> > > +     node->next_frm = NULL;
> > > +}
> > > +
> > > +static void unicam_process_buffer_complete(struct unicam_node *node,
> > > +                                        unsigned int sequence)
> > > +{
> > > +     node->cur_frm->vb.field = node->fmt.fmt.pix.field;
> > > +     node->cur_frm->vb.sequence = sequence;
> > > +
> > > +     vb2_buffer_done(&node->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
> > > +}
> > > +
> > > +static void unicam_queue_event_sof(struct unicam_device *unicam)
> > > +{
> > > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +
> > > +     struct v4l2_event event = {
> > > +             .type = V4L2_EVENT_FRAME_SYNC,
> > > +             .u.frame_sync.frame_sequence = unicam->sequence,
> > > +     };
> > > +
> > > +     v4l2_event_queue(&node->video_dev, &event);
> > > +}
> > > +
> > > +static irqreturn_t unicam_isr(int irq, void *dev)
> > > +{
> > > +     struct unicam_device *unicam = dev;
> > > +     unsigned int lines_done = unicam_get_lines_done(dev);
> > > +     unsigned int sequence = unicam->sequence;
> > > +     unsigned int i;
> > > +     u32 ista, sta;
> > > +     bool fe;
> > > +     u64 ts;
> > > +
> > > +     sta = unicam_reg_read(unicam, UNICAM_STA);
> > > +     /* Write value back to clear the interrupts */
> > > +     unicam_reg_write(unicam, UNICAM_STA, sta);
> > > +
> > > +     ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > > +     /* Write value back to clear the interrupts */
> > > +     unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > > +
> > > +     dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > > +             ista, sta, sequence, lines_done);
> > > +
> > > +     if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > > +             return IRQ_HANDLED;
> > > +
> > > +     /*
> > > +      * Look for either the Frame End interrupt or the Packet Capture status
> > > +      * to signal a frame end.
> > > +      */
> > > +     fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > > +
> > > +     /*
> > > +      * We must run the frame end handler first. If we have a valid next_frm
> > > +      * and we get a simultaneout FE + FS interrupt, running the FS handler
> > > +      * first would null out the next_frm ptr and we would have lost the
> > > +      * buffer forever.
> > > +      */
> > > +     if (fe) {
> > > +             /*
> > > +              * Ensure we have swapped buffers already as we can't
> > > +              * stop the peripheral. If no buffer is available, use a
> > > +              * dummy buffer to dump out frames until we get a new buffer
> > > +              * to use.
> > > +              */
> > > +             for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +                     if (!unicam->node[i].streaming)
> > > +                             continue;
> > > +
> > > +                     /*
> > > +                      * If cur_frm == next_frm, it means we have not had
> > > +                      * a chance to swap buffers, likely due to having
> > > +                      * multiple interrupts occurring simultaneously (like FE
> > > +                      * + FS + LS). In this case, we cannot signal the buffer
> > > +                      * as complete, as the HW will reuse that buffer.
> > > +                      */
> > > +                     if (unicam->node[i].cur_frm &&
> > > +                         unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > > +                             unicam_process_buffer_complete(&unicam->node[i],
> > > +                                                            sequence);
> > > +                     unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > > +             }
> > > +             unicam->sequence++;
> > > +     }
> > > +
> > > +     if (ista & UNICAM_FSI) {
> > > +             /*
> > > +              * Timestamp is to be when the first data byte was captured,
> > > +              * aka frame start.
> > > +              */
> > > +             ts = ktime_get_ns();
> > > +             for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +                     if (!unicam->node[i].streaming)
> > > +                             continue;
> > > +
> > > +                     if (unicam->node[i].cur_frm)
> > > +                             unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > > +                                                             ts;
> > > +                     else
> > > +                             dev_dbg(unicam->v4l2_dev.dev,
> > > +                                     "ISR: [%d] Dropping frame, buffer not available at FS\n",
> > > +                                     i);
> > > +                     /*
> > > +                      * Set the next frame output to go to a dummy frame
> > > +                      * if we have not managed to obtain another frame
> > > +                      * from the queue.
> > > +                      */
> > > +                     unicam_schedule_dummy_buffer(&unicam->node[i]);
> > > +             }
> > > +
> > > +             unicam_queue_event_sof(unicam);
> > > +     }
> > > +
> > > +     /*
> > > +      * Cannot swap buffer at frame end, there may be a race condition
> > > +      * where the HW does not actually swap it if the new frame has
> > > +      * already started.
> > > +      */
> > > +     if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > > +             for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +                     if (!unicam->node[i].streaming)
> > > +                             continue;
> > > +
> > > +                     spin_lock(&unicam->node[i].dma_queue_lock);
> > > +                     if (!list_empty(&unicam->node[i].dma_queue) &&
> > > +                         !unicam->node[i].next_frm)
> > > +                             unicam_schedule_next_buffer(&unicam->node[i]);
> > > +                     spin_unlock(&unicam->node[i].dma_queue_lock);
> > > +             }
> > > +     }
> > > +
> > > +     if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > > +             /* Switch out of trigger mode if selected */
> > > +             unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > +             unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > > +     }
> > > +     return IRQ_HANDLED;
> > > +}
> > > +
> > > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > > +{
> > > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +     u32 pack, unpack;
> > > +     u32 val;
> > > +
> > > +     if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > > +             unpack = UNICAM_PUM_NONE;
> > > +             pack = UNICAM_PPM_NONE;
> > > +     } else {
> > > +             switch (node->fmtinfo->depth) {
> > > +             case 8:
> > > +                     unpack = UNICAM_PUM_UNPACK8;
> > > +                     break;
> > > +             case 10:
> > > +                     unpack = UNICAM_PUM_UNPACK10;
> > > +                     break;
> > > +             case 12:
> > > +                     unpack = UNICAM_PUM_UNPACK12;
> > > +                     break;
> > > +             case 14:
> > > +                     unpack = UNICAM_PUM_UNPACK14;
> > > +                     break;
> > > +             case 16:
> > > +                     unpack = UNICAM_PUM_UNPACK16;
> > > +                     break;
> > > +             default:
> > > +                     unpack = UNICAM_PUM_NONE;
> > > +                     break;
> > > +             }
> > > +
> > > +             /* Repacking is always to 16bpp */
> > > +             pack = UNICAM_PPM_PACK16;
> > > +     }
> > > +
> > > +     val = 0;
> > > +     unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> > > +     unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> > > +     unicam_reg_write(unicam, UNICAM_IPIPE, val);
> > > +}
> > > +
> > > +static void unicam_cfg_image_id(struct unicam_device *unicam)
> > > +{
> > > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +
> > > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +             /* CSI2 mode, hardcode VC 0 for now. */
> > > +             unicam_reg_write(unicam, UNICAM_IDI0,
> > > +                              (0 << 6) | node->fmtinfo->csi_dt);
> > > +     } else {
> > > +             /* CCP2 mode */
> > > +             unicam_reg_write(unicam, UNICAM_IDI0,
> > > +                              0x80 | node->fmtinfo->csi_dt);
> > > +     }
> > > +}
> > > +
> > > +static void unicam_enable_ed(struct unicam_device *unicam)
> > > +{
> > > +     u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> > > +
> > > +     unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> > > +     /* Do not wrap at the end of the embedded data buffer */
> > > +     unicam_set_field(&val, 0, UNICAM_DBOB);
> > > +
> > > +     unicam_reg_write(unicam, UNICAM_DCS, val);
> > > +}
> > > +
> > > +static void unicam_start_rx(struct unicam_device *unicam,
> > > +                         struct unicam_buffer *buf)
> > > +{
> > > +     struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +     int line_int_freq = node->fmt.fmt.pix.height >> 2;
> > > +     unsigned int i;
> > > +     u32 val;
> > > +
> > > +     if (line_int_freq < 128)
> > > +             line_int_freq = 128;
> > > +
> > > +     /* Enable lane clocks */
> > > +     val = 1;
> > > +     for (i = 0; i < unicam->active_data_lanes; i++)
> > > +             val = val << 2 | 1;
> > > +     unicam_clk_write(unicam, val);
> > > +
> > > +     /* Basic init */
> > > +     unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> > > +
> > > +     /* Enable analogue control, and leave in reset. */
> > > +     val = UNICAM_AR;
> > > +     unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> > > +     unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> > > +     unicam_reg_write(unicam, UNICAM_ANA, val);
> > > +     usleep_range(1000, 2000);
> > > +
> > > +     /* Come out of reset */
> > > +     unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> > > +
> > > +     /* Peripheral reset */
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > > +
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > > +
> > > +     /* Enable Rx control. */
> > > +     val = unicam_reg_read(unicam, UNICAM_CTRL);
> > > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +             unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> > > +             unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> > > +     } else {
> > > +             unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> > > +             unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> > > +     }
> > > +     /* Packet framer timeout */
> > > +     unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> > > +     unicam_set_field(&val, 128, UNICAM_OET_MASK);
> > > +     unicam_reg_write(unicam, UNICAM_CTRL, val);
> > > +
> > > +     unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> > > +     unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> > > +
> > > +     /* AXI bus access QoS setup */
> > > +     val = unicam_reg_read(unicam, UNICAM_PRI);
> > > +     unicam_set_field(&val, 0, UNICAM_BL_MASK);
> > > +     unicam_set_field(&val, 0, UNICAM_BS_MASK);
> > > +     unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> > > +     unicam_set_field(&val, 8, UNICAM_NP_MASK);
> > > +     unicam_set_field(&val, 2, UNICAM_PT_MASK);
> > > +     unicam_set_field(&val, 1, UNICAM_PE);
> > > +     unicam_reg_write(unicam, UNICAM_PRI, val);
> > > +
> > > +     unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> > > +
> > > +     /* Always start in trigger frame capture mode (UNICAM_FCM set) */
> > > +     val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> > > +     unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> > > +     unicam_reg_write(unicam, UNICAM_ICTL, val);
> > > +     unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> > > +     unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> > > +
> > > +     /* tclk_term_en */
> > > +     unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> > > +     /* tclk_settle */
> > > +     unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> > > +     /* td_term_en */
> > > +     unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> > > +     /* ths_settle */
> > > +     unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> > > +     /* trx_enable */
> > > +     unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> > > +
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> > > +
> > > +     /* Packet compare setup - required to avoid missing frame ends */
> > > +     val = 0;
> > > +     unicam_set_field(&val, 1, UNICAM_PCE);
> > > +     unicam_set_field(&val, 1, UNICAM_GI);
> > > +     unicam_set_field(&val, 1, UNICAM_CPH);
> > > +     unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> > > +     unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> > > +     unicam_reg_write(unicam, UNICAM_CMP0, val);
> > > +
> > > +     /* Enable clock lane and set up terminations */
> > > +     val = 0;
> > > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +             /* CSI2 */
> > > +             unicam_set_field(&val, 1, UNICAM_CLE);
> > > +             unicam_set_field(&val, 1, UNICAM_CLLPE);
> > > +             if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > > +                     unicam_set_field(&val, 1, UNICAM_CLTRE);
> > > +                     unicam_set_field(&val, 1, UNICAM_CLHSE);
> > > +             }
> > > +     } else {
> > > +             /* CCP2 */
> > > +             unicam_set_field(&val, 1, UNICAM_CLE);
> > > +             unicam_set_field(&val, 1, UNICAM_CLHSE);
> > > +             unicam_set_field(&val, 1, UNICAM_CLTRE);
> > > +     }
> > > +     unicam_reg_write(unicam, UNICAM_CLK, val);
> > > +
> > > +     /*
> > > +      * Enable required data lanes with appropriate terminations.
> > > +      * The same value needs to be written to UNICAM_DATn registers for
> > > +      * the active lanes, and 0 for inactive ones.
> > > +      */
> > > +     val = 0;
> > > +     if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +             /* CSI2 */
> > > +             unicam_set_field(&val, 1, UNICAM_DLE);
> > > +             unicam_set_field(&val, 1, UNICAM_DLLPE);
> > > +             if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > > +                     unicam_set_field(&val, 1, UNICAM_DLTRE);
> > > +                     unicam_set_field(&val, 1, UNICAM_DLHSE);
> > > +             }
> > > +     } else {
> > > +             /* CCP2 */
> > > +             unicam_set_field(&val, 1, UNICAM_DLE);
> > > +             unicam_set_field(&val, 1, UNICAM_DLHSE);
> > > +             unicam_set_field(&val, 1, UNICAM_DLTRE);
> > > +     }
> > > +     unicam_reg_write(unicam, UNICAM_DAT0, val);
> > > +
> > > +     if (unicam->active_data_lanes == 1)
> > > +             val = 0;
> > > +     unicam_reg_write(unicam, UNICAM_DAT1, val);
> > > +
> > > +     if (unicam->max_data_lanes > 2) {
> > > +             /*
> > > +              * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> > > +              * instance supports more than 2 data lanes.
> > > +              */
> > > +             if (unicam->active_data_lanes == 2)
> > > +                     val = 0;
> > > +             unicam_reg_write(unicam, UNICAM_DAT2, val);
> > > +
> > > +             if (unicam->active_data_lanes == 3)
> > > +                     val = 0;
> > > +             unicam_reg_write(unicam, UNICAM_DAT3, val);
> > > +     }
> > > +
> > > +     unicam_reg_write(unicam, UNICAM_IBLS,
> > > +                      node->fmt.fmt.pix.bytesperline);
> > > +     unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> > > +     unicam_set_packing_config(unicam);
> > > +     unicam_cfg_image_id(unicam);
> > > +
> > > +     val = unicam_reg_read(unicam, UNICAM_MISC);
> > > +     unicam_set_field(&val, 1, UNICAM_FL0);
> > > +     unicam_set_field(&val, 1, UNICAM_FL1);
> > > +     unicam_reg_write(unicam, UNICAM_MISC, val);
> > > +
> > > +     /* Enable peripheral */
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> > > +
> > > +     /* Load image pointers */
> > > +     unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> > > +
> > > +     /*
> > > +      * Enable trigger only for the first frame to
> > > +      * sync correctly to the FS from the source.
> > > +      */
> > > +     unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > +}
> > > +
> > > +static void unicam_start_metadata(struct unicam_device *unicam,
> > > +                               struct unicam_buffer *buf)
> > > +{
> > > +     struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
> > > +
> > > +     unicam_enable_ed(unicam);
> > > +     unicam_wr_dma_addr(node, buf);
> > > +     unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
> > > +}
> > > +
> > > +static void unicam_disable(struct unicam_device *unicam)
> > > +{
> > > +     /* Analogue lane control disable */
> > > +     unicam_reg_write_field(unicam, UNICAM_ANA, 1, UNICAM_DDL);
> > > +
> > > +     /* Stop the output engine */
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_SOE);
> > > +
> > > +     /* Disable the data lanes. */
> > > +     unicam_reg_write(unicam, UNICAM_DAT0, 0);
> > > +     unicam_reg_write(unicam, UNICAM_DAT1, 0);
> > > +
> > > +     if (unicam->max_data_lanes > 2) {
> > > +             unicam_reg_write(unicam, UNICAM_DAT2, 0);
> > > +             unicam_reg_write(unicam, UNICAM_DAT3, 0);
> > > +     }
> > > +
> > > +     /* Peripheral reset */
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > > +     usleep_range(50, 100);
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > > +
> > > +     /* Disable peripheral */
> > > +     unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > > +
> > > +     /* Clear ED setup */
> > > +     unicam_reg_write(unicam, UNICAM_DCS, 0);
> > > +
> > > +     /* Disable all lane clocks */
> > > +     unicam_clk_write(unicam, 0);
> > > +}
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + * V4L2 subdev operations
> > > + */
> > > +
> > > +static int __unicam_subdev_set_routing(struct v4l2_subdev *sd,
> > > +                                    struct v4l2_subdev_state *state,
> > > +                                    struct v4l2_subdev_krouting *routing)
> > > +{
> > > +     struct v4l2_subdev_route *route;
> > > +     int ret;
> > > +
> > > +     ret = v4l2_subdev_routing_validate(sd, routing,
> > > +                                        V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = v4l2_subdev_set_routing(sd, state, routing);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     for_each_active_route(&state->routing, route) {
> > > +             const struct v4l2_mbus_framefmt *def_fmt;
> > > +             struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +             if (route->source_pad == UNICAM_SD_PAD_SOURCE_IMAGE)
> > > +                     def_fmt = &unicam_default_image_format;
> > > +             else
> > > +                     def_fmt = &unicam_default_meta_format;
> > > +
> > > +             fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
> > > +                                                route->sink_stream);
> > > +             *fmt = *def_fmt;
> > > +             fmt = v4l2_subdev_state_get_format(state, route->source_pad,
> > > +                                                route->source_stream);
> > > +             *fmt = *def_fmt;
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_subdev_init_state(struct v4l2_subdev *sd,
> > > +                                 struct v4l2_subdev_state *state)
> > > +{
> > > +     struct v4l2_subdev_route routes[] = {
> > > +             {
> > > +                     .sink_pad = UNICAM_SD_PAD_SINK,
> > > +                     .sink_stream = 0,
> > > +                     .source_pad = UNICAM_SD_PAD_SOURCE_IMAGE,
> > > +                     .source_stream = 0,
> > > +                     .flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
> > > +             },
> > > +     };
> > > +
> > > +     struct v4l2_subdev_krouting routing = {
> > > +             .len_routes = ARRAY_SIZE(routes),
> > > +             .num_routes = ARRAY_SIZE(routes),
> > > +             .routes = routes,
> > > +     };
> > > +
> > > +     /* Initialize routing to single route to the fist source pad. */
> > > +     return __unicam_subdev_set_routing(sd, state, &routing);
> > > +}
> > > +
> > > +static int unicam_subdev_enum_mbus_code(struct v4l2_subdev *sd,
> > > +                                     struct v4l2_subdev_state *state,
> > > +                                     struct v4l2_subdev_mbus_code_enum *code)
> > > +{
> > > +     u32 pad, stream;
> > > +     int ret;
> > > +
> > > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > > +                                                 code->pad, code->stream,
> > > +                                                 &pad, &stream);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (unicam_sd_pad_is_source(code->pad)) {
> > > +             /* No transcoding, source and sink codes must match. */
> > > +             const struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +             fmt = v4l2_subdev_state_get_format(state, pad, stream);
> > > +             if (!fmt)
> > > +                     return -EINVAL;
> > > +
> > > +             if (code->index > 0)
> > > +                     return -EINVAL;
> > > +
> > > +             code->code = fmt->code;
> > > +     } else {
> > > +             const struct unicam_format_info *formats;
> > > +             unsigned int num_formats;
> > > +
> > > +             if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > > +                     formats = unicam_image_formats;
> > > +                     num_formats = ARRAY_SIZE(unicam_image_formats);
> > > +             } else {
> > > +                     formats = unicam_meta_formats;
> > > +                     num_formats = ARRAY_SIZE(unicam_meta_formats);
> > > +             }
> > > +
> > > +             if (code->index >= num_formats)
> > > +                     return -EINVAL;
> > > +
> > > +             code->code = formats[code->index].code;
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_subdev_enum_frame_size(struct v4l2_subdev *sd,
> > > +                                      struct v4l2_subdev_state *state,
> > > +                                      struct v4l2_subdev_frame_size_enum *fse)
> > > +{
> > > +     u32 pad, stream;
> > > +     int ret;
> > > +
> > > +     if (fse->index > 0)
> > > +             return -EINVAL;
> > > +
> > > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing, fse->pad,
> > > +                                                 fse->stream, &pad,
> > > +                                                 &stream);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     if (unicam_sd_pad_is_source(fse->pad)) {
> > > +             /* No transcoding, source and sink formats must match. */
> > > +             const struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +             fmt = v4l2_subdev_state_get_format(state, pad, stream);
> > > +             if (!fmt)
> > > +                     return -EINVAL;
> > > +
> > > +             if (fse->code != fmt->code)
> > > +                     return -EINVAL;
> > > +
> > > +             fse->min_width = fmt->width;
> > > +             fse->max_width = fmt->width;
> > > +             fse->min_height = fmt->height;
> > > +             fse->max_height = fmt->height;
> > > +     } else {
> > > +             const struct unicam_format_info *fmtinfo;
> > > +
> > > +             fmtinfo = unicam_find_format_by_code(fse->code, pad);
> > > +             if (!fmtinfo)
> > > +                     return -EINVAL;
> > > +
> > > +             if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > > +                     fse->min_width = UNICAM_IMAGE_MIN_WIDTH;
> > > +                     fse->max_width = UNICAM_IMAGE_MAX_WIDTH;
> > > +                     fse->min_height = UNICAM_IMAGE_MIN_HEIGHT;
> > > +                     fse->max_height = UNICAM_IMAGE_MAX_HEIGHT;
> > > +             } else {
> > > +                     fse->min_width = UNICAM_META_MIN_WIDTH;
> > > +                     fse->max_width = UNICAM_META_MAX_WIDTH;
> > > +                     fse->min_height = UNICAM_META_MIN_HEIGHT;
> > > +                     fse->max_height = UNICAM_META_MAX_HEIGHT;
> > > +             }
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_subdev_set_format(struct v4l2_subdev *sd,
> > > +                                 struct v4l2_subdev_state *state,
> > > +                                 struct v4l2_subdev_format *format)
> > > +{
> > > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > > +     struct v4l2_mbus_framefmt *sink_format, *source_format;
> > > +     const struct unicam_format_info *fmtinfo;
> > > +     u32 source_pad, source_stream;
> > > +     int ret;
> > > +
> > > +     if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
> > > +         unicam->subdev.streaming)
> > > +             return -EBUSY;
> > > +
> > > +     /* No transcoding, source and sink formats must match. */
> > > +     if (unicam_sd_pad_is_source(format->pad))
> > > +             return v4l2_subdev_get_fmt(sd, state, format);
> > > +
> > > +     /*
> > > +      * Allowed formats for the stream on the sink pad depend on what source
> > > +      * pad the stream is routed to. Find the corresponding source pad and
> > > +      * use it to validate the media bus code.
> > > +      */
> > > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > > +                                                 format->pad, format->stream,
> > > +                                                 &source_pad, &source_stream);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     fmtinfo = unicam_find_format_by_code(format->format.code, source_pad);
> > > +     if (!fmtinfo) {
> > > +             fmtinfo = source_pad == UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                     ? &unicam_image_formats[0] : &unicam_meta_formats[0];
> > > +             format->format.code = fmtinfo->code;
> > > +     }
> > > +
> > > +     if (source_pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> > > +             format->format.width = clamp_t(unsigned int,
> > > +                                            format->format.width,
> > > +                                            UNICAM_IMAGE_MIN_WIDTH,
> > > +                                            UNICAM_IMAGE_MAX_WIDTH);
> > > +             format->format.height = clamp_t(unsigned int,
> > > +                                             format->format.height,
> > > +                                             UNICAM_IMAGE_MIN_HEIGHT,
> > > +                                             UNICAM_IMAGE_MAX_HEIGHT);
> > > +             format->format.field = V4L2_FIELD_NONE;
> > > +     } else {
> > > +             format->format.width = clamp_t(unsigned int,
> > > +                                            format->format.width,
> > > +                                            UNICAM_META_MIN_WIDTH,
> > > +                                            UNICAM_META_MAX_WIDTH);
> > > +             format->format.height = clamp_t(unsigned int,
> > > +                                             format->format.height,
> > > +                                             UNICAM_META_MIN_HEIGHT,
> > > +                                             UNICAM_META_MAX_HEIGHT);
> > > +             format->format.field = V4L2_FIELD_NONE;
> > > +
> > > +             /* Colorspace don't apply to metadata. */
> > > +             format->format.colorspace = 0;
> > > +             format->format.ycbcr_enc = 0;
> > > +             format->format.quantization = 0;
> > > +             format->format.xfer_func = 0;
> > > +     }
> > > +
> > > +     sink_format = v4l2_subdev_state_get_format(state, format->pad,
> > > +                                                format->stream);
> > > +     source_format = v4l2_subdev_state_get_format(state, source_pad,
> > > +                                                  source_stream);
> > > +     *sink_format = format->format;
> > > +     *source_format = format->format;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_subdev_set_routing(struct v4l2_subdev *sd,
> > > +                                  struct v4l2_subdev_state *state,
> > > +                                  enum v4l2_subdev_format_whence which,
> > > +                                  struct v4l2_subdev_krouting *routing)
> > > +{
> > > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > > +
> > > +     if (which == V4L2_SUBDEV_FORMAT_ACTIVE && unicam->subdev.streaming)
> > > +             return -EBUSY;
> > > +
> > > +     return __unicam_subdev_set_routing(sd, state, routing);
> > > +}
> > > +
> > > +static int unicam_sd_enable_streams(struct v4l2_subdev *sd,
> > > +                                 struct v4l2_subdev_state *state, u32 pad,
> > > +                                 u64 streams_mask)
> > > +{
> > > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > > +     u32 other_pad, other_stream;
> > > +     int ret;
> > > +
> > > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> > > +                                                 &other_pad, &other_stream);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     unicam->sequence = 0;
> > > +
> > > +     ret = v4l2_subdev_enable_streams(unicam->sensor.subdev,
> > > +                                      unicam->sensor.pad->index,
> > > +                                      BIT(other_stream));
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "stream on failed in subdev\n");
> > > +             return ret;
> > > +     }
> > > +
> > > +     unicam->subdev.streaming = true;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_sd_disable_streams(struct v4l2_subdev *sd,
> > > +                                  struct v4l2_subdev_state *state, u32 pad,
> > > +                                  u64 streams_mask)
> > > +{
> > > +     struct unicam_device *unicam = sd_to_unicam_device(sd);
> > > +     u32 other_pad, other_stream;
> > > +     int ret;
> > > +
> > > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> > > +                                                 &other_pad, &other_stream);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     v4l2_subdev_disable_streams(unicam->sensor.subdev,
> > > +                                 unicam->sensor.pad->index,
> > > +                                 BIT(other_stream));
> > > +
> > > +     unicam->subdev.streaming = false;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct v4l2_subdev_pad_ops unicam_subdev_pad_ops = {
> > > +     .enum_mbus_code         = unicam_subdev_enum_mbus_code,
> > > +     .enum_frame_size        = unicam_subdev_enum_frame_size,
> > > +     .get_fmt                = v4l2_subdev_get_fmt,
> > > +     .set_fmt                = unicam_subdev_set_format,
> > > +     .set_routing            = unicam_subdev_set_routing,
> > > +     .enable_streams         = unicam_sd_enable_streams,
> > > +     .disable_streams        = unicam_sd_disable_streams,
> > > +};
> > > +
> > > +static const struct v4l2_subdev_ops unicam_subdev_ops = {
> > > +     .pad                    = &unicam_subdev_pad_ops,
> > > +};
> > > +
> > > +static const struct v4l2_subdev_internal_ops unicam_subdev_internal_ops = {
> > > +     .init_state             = unicam_subdev_init_state,
> > > +};
> > > +
> > > +static const struct media_entity_operations unicam_subdev_media_ops = {
> > > +     .link_validate          = v4l2_subdev_link_validate,
> > > +     .has_pad_interdep       = v4l2_subdev_has_pad_interdep,
> > > +};
> > > +
> > > +static int unicam_subdev_init(struct unicam_device *unicam)
> > > +{
> > > +     struct v4l2_subdev *sd = &unicam->subdev.sd;
> > > +     int ret;
> > > +
> > > +     v4l2_subdev_init(sd, &unicam_subdev_ops);
> > > +     sd->internal_ops = &unicam_subdev_internal_ops;
> > > +     v4l2_set_subdevdata(sd, unicam);
> > > +
> > > +     sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> > > +     sd->entity.ops = &unicam_subdev_media_ops;
> > > +     sd->dev = unicam->dev;
> > > +     sd->owner = THIS_MODULE;
> > > +     sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
> > > +
> > > +     strscpy(sd->name, "unicam", sizeof(sd->name));
> > > +
> > > +     unicam->subdev.pads[UNICAM_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> > > +     unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_IMAGE].flags = MEDIA_PAD_FL_SOURCE;
> > > +     unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_METADATA].flags = MEDIA_PAD_FL_SOURCE;
> > > +
> > > +     ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(unicam->subdev.pads),
> > > +                                  unicam->subdev.pads);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "Failed to initialize media entity: %d\n",
> > > +                     ret);
> > > +             return ret;
> > > +     }
> > > +
> > > +     ret = v4l2_subdev_init_finalize(sd);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "Failed to initialize subdev: %d\n", ret);
> > > +             goto err_entity;
> > > +     }
> > > +
> > > +     ret = v4l2_device_register_subdev(&unicam->v4l2_dev, sd);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "Failed to register subdev: %d\n", ret);
> > > +             goto err_subdev;
> > > +     }
> > > +
> > > +     return 0;
> > > +
> > > +err_subdev:
> > > +     v4l2_subdev_cleanup(sd);
> > > +err_entity:
> > > +     media_entity_cleanup(&sd->entity);
> > > +     return ret;
> > > +}
> > > +
> > > +static void unicam_subdev_cleanup(struct unicam_device *unicam)
> > > +{
> > > +     v4l2_subdev_cleanup(&unicam->subdev.sd);
> > > +     media_entity_cleanup(&unicam->subdev.sd.entity);
> > > +}
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + * Videobuf2 queue operations
> > > + */
> > > +
> > > +static int unicam_queue_setup(struct vb2_queue *vq,
> > > +                           unsigned int *nbuffers,
> > > +                           unsigned int *nplanes,
> > > +                           unsigned int sizes[],
> > > +                           struct device *alloc_devs[])
> > > +{
> > > +     struct unicam_node *node = vb2_get_drv_priv(vq);
> > > +     u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > > +              : node->fmt.fmt.meta.buffersize;
> > > +
> > > +     if (vq->num_buffers + *nbuffers < 3)
> >
> > Why 3 ? Are these dummies ?
> >
> > > +             *nbuffers = 3 - vq->num_buffers;
> > > +
> > > +     if (*nplanes) {
> > > +             if (sizes[0] < size) {
> > > +                     dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> > > +                             sizes[0], size);
> > > +                     return -EINVAL;
> > > +             }
> > > +             size = sizes[0];
> > > +     }
> > > +
> > > +     *nplanes = 1;
> > > +     sizes[0] = size;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_buffer_prepare(struct vb2_buffer *vb)
> > > +{
> > > +     struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > > +     struct unicam_buffer *buf = to_unicam_buffer(vb);
> > > +     u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > > +              : node->fmt.fmt.meta.buffersize;
> > > +
> > > +     if (vb2_plane_size(vb, 0) < size) {
> > > +             dev_dbg(node->dev->dev,
> > > +                     "data will not fit into plane (%lu < %u)\n",
> > > +                     vb2_plane_size(vb, 0), size);
> > > +             return -EINVAL;
> > > +     }
> > > +
> > > +     buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> > > +     buf->size = size;
> > > +
> > > +     vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static void unicam_return_buffers(struct unicam_node *node,
> > > +                               enum vb2_buffer_state state)
> > > +{
> > > +     struct unicam_buffer *buf, *tmp;
> > > +
> > > +     list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> > > +             list_del(&buf->list);
> > > +             vb2_buffer_done(&buf->vb.vb2_buf, state);
> > > +     }
> > > +
> > > +     if (node->cur_frm)
> > > +             vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> > > +                             state);
> > > +     if (node->next_frm && node->cur_frm != node->next_frm)
> > > +             vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> > > +                             state);
> > > +
> > > +     node->cur_frm = NULL;
> > > +     node->next_frm = NULL;
> > > +}
> > > +
> > > +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> > > +{
> > > +     struct unicam_node *node = vb2_get_drv_priv(vq);
> > > +     struct unicam_device *unicam = node->dev;
> > > +     struct v4l2_subdev_state *state;
> > > +     struct unicam_buffer *buf;
> > > +     unsigned long flags;
> > > +     int ret;
> > > +     u32 pad, stream;
> > > +     u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                                          : UNICAM_SD_PAD_SOURCE_METADATA;
> > > +
> > > +     /* Look for the route for the given pad and stream. */
> > > +     state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> > > +     ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > > +                                                 remote_pad, 0,
> > > +                                                 &pad, &stream);
> > > +     v4l2_subdev_unlock_state(state);
> > > +
> > > +     if (ret)
> > > +             goto err_return_buffers;
> 
> You've dropped calling get_mbus_config from in or around this area,
> therefore any device that supports dynamic switching on number of data
> lanes (eg tc358743) is broken.
> Docs guidance is
> "Callers should make sure they get the most up-to-date as possible
> configuration from the remote end, likely calling this operation as
> close as possible to stream on time"
> https://www.kernel.org/doc/html/latest/driver-api/media/v4l2-subdev.html?highlight=get_mbus_config

Indeed, my bad (actually I'm not sure who dropped it, the driver went
through multiple iterations, but that doesn't matter :-)). I'll add it
back.

> > > +
> > > +     dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> > > +             unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> > > +             is_metadata_node(node) ? "metadata" : "image");
> > > +
> > > +     /* The metadata node can't be started alone. */
> > > +     if (is_metadata_node(node)) {
> > > +             if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> >
> > Does it mean the metadata node has to be started second, or should
> > this be made a nop and the metadata node gets started once the image
> > node is started too ? I'm fine with the constraint of having the
> > metadata node being started second fwiw
> 
> This has been flipped from the downstream implementation.
> Downstream we expected the metadata node to be enabled first, but it
> wouldn't get started until the image node was enabled.

Unless I'm mistaken, the downstream implementation waits for both nodes
to be started before starting the device.

> Things like sequence numbers come to mind now that this is enabling
> the image node first. If the image node has produced the first frame
> before the metadata node has been enabled, then as I read it the
> sequence numbers for the two nodes should be different - there haven't
> really been any dropped frames as you hadn't enabled the node.
> 
> I'd also want to confirm what the behaviour is if the frame has
> already started before the metadata node is enabled. Embedded data is
> almost always sent before the image data, so have we potentially
> missed it for the current frame, but at the end of frame are going to
> return both buffers?

I think we have a possible race condition here. I'll think a bit more
about it.

> > > +                     dev_err(unicam->dev,
> > > +                             "Can't start metadata without image\n");
> > > +                     ret = -EINVAL;
> > > +                     goto err_return_buffers;
> > > +             }
> > > +
> > > +             spin_lock_irqsave(&node->dma_queue_lock, flags);
> > > +             buf = list_first_entry(&node->dma_queue,
> > > +                                    struct unicam_buffer, list);
> > > +             dev_dbg(unicam->dev, "buffer %p\n", buf);
> >
> > Is this useful ?
> >
> > > +             node->cur_frm = buf;
> > > +             node->next_frm = buf;
> > > +             list_del(&buf->list);
> > > +             spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > > +
> > > +             unicam_start_metadata(unicam, buf);
> > > +             node->streaming = true;
> > > +             return 0;
> > > +     }
> > > +
> > > +     ret = pm_runtime_resume_and_get(unicam->dev);
> > > +     if (ret < 0) {
> > > +             dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> > > +             goto err_return_buffers;
> > > +     }
> > > +
> > > +     ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> > > +     if (ret < 0) {
> > > +             dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> >
> > Isn't this an err ?
> >
> > > +             goto err_pm_put;
> > > +     }
> > > +
> > > +     spin_lock_irqsave(&node->dma_queue_lock, flags);
> > > +     buf = list_first_entry(&node->dma_queue,
> > > +                            struct unicam_buffer, list);
> > > +     dev_dbg(unicam->dev, "buffer %p\n", buf);
> > > +     node->cur_frm = buf;
> > > +     node->next_frm = buf;
> > > +     list_del(&buf->list);
> > > +     spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > > +
> > > +     unicam_start_rx(unicam, buf);
> > > +
> > > +     ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> >
> > A bit confused by the API here, shouldn't we also do this for embedded
> > data ?
> >
> > > +     if (ret < 0) {
> > > +             dev_err(unicam->dev, "stream on failed in subdev\n");
> > > +             goto error_pipeline;
> > > +     }
> > > +
> > > +     node->streaming = true;
> > > +
> > > +     return 0;
> > > +
> > > +error_pipeline:
> > > +     video_device_pipeline_stop(&node->video_dev);
> > > +err_pm_put:
> > > +     pm_runtime_put_sync(unicam->dev);
> > > +err_return_buffers:
> > > +     unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> > > +     return ret;
> > > +}
> > > +
> > > +static void unicam_stop_streaming(struct vb2_queue *vq)
> > > +{
> > > +     struct unicam_node *node = vb2_get_drv_priv(vq);
> > > +     struct unicam_device *unicam = node->dev;
> > > +     u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                                                : UNICAM_SD_PAD_SOURCE_METADATA;
> > > +
> > > +     node->streaming = false;
> > > +
> > > +     v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> > > +                                 BIT(0));
> > > +
> > > +     /* We can stream only with the image node. */
> > > +     if (is_metadata_node(node)) {
> > > +             /*
> > > +              * Allow the hardware to spin in the dummy buffer.
> > > +              * This is only really needed if the embedded data pad is
> > > +              * disabled before the image pad.
> > > +              */
> > > +             unicam_wr_dma_addr(node, &node->dummy_buf);
> > > +             goto dequeue_buffers;
> > > +     }
> > > +
> > > +     unicam_disable(unicam);
> > > +
> > > +     video_device_pipeline_stop(&node->video_dev);
> > > +     pm_runtime_put(unicam->dev);
> > > +
> > > +dequeue_buffers:
> > > +     /* Clear all queued buffers for the node */
> > > +     unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> > > +}
> > > +
> > > +static void unicam_buffer_queue(struct vb2_buffer *vb)
> > > +{
> > > +     struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> > > +     struct unicam_buffer *buf = to_unicam_buffer(vb);
> > > +
> > > +     spin_lock_irq(&node->dma_queue_lock);
> > > +     list_add_tail(&buf->list, &node->dma_queue);
> > > +     spin_unlock_irq(&node->dma_queue_lock);
> > > +}
> > > +
> > > +static const struct vb2_ops unicam_video_qops = {
> > > +     .queue_setup            = unicam_queue_setup,
> > > +     .wait_prepare           = vb2_ops_wait_prepare,
> > > +     .wait_finish            = vb2_ops_wait_finish,
> > > +     .buf_prepare            = unicam_buffer_prepare,
> > > +     .start_streaming        = unicam_start_streaming,
> > > +     .stop_streaming         = unicam_stop_streaming,
> > > +     .buf_queue              = unicam_buffer_queue,
> > > +};
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + *  V4L2 video device operations
> > > + */
> > > +
> > > +static int unicam_querycap(struct file *file, void *priv,
> > > +                        struct v4l2_capability *cap)
> > > +{
> > > +     strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> > > +     strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> > > +
> > > +     cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> > > +                            struct v4l2_fmtdesc *f)
> > > +{
> > > +     unsigned int index;
> > > +     unsigned int i;
> > > +
> > > +     for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> > > +             if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> > > +                     continue;
> > > +
> > > +             if (index == f->index) {
> > > +                     f->pixelformat = unicam_image_formats[i].fourcc;
> > > +                     return 0;
> > > +             }
> > > +
> > > +             index++;
> > > +
> > > +             if (!unicam_image_formats[i].unpacked_fourcc)
> > > +                     continue;
> > > +
> > > +             if (index == f->index) {
> > > +                     f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> > > +                     return 0;
> > > +             }
> > > +
> > > +             index++;
> > > +     }
> > > +
> > > +     return -EINVAL;
> > > +}
> > > +
> > > +static int unicam_g_fmt_vid(struct file *file, void *priv,
> > > +                         struct v4l2_format *f)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +
> > > +     *f = node->fmt;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct unicam_format_info *
> > > +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> > > +{
> > > +     const struct unicam_format_info *fmtinfo;
> > > +
> > > +     /*
> > > +      * Default to the first format if the requested pixel format code isn't
> > > +      * supported.
> > > +      */
> > > +     fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> > > +                                            UNICAM_SD_PAD_SOURCE_IMAGE);
> > > +     if (!fmtinfo) {
> > > +             fmtinfo = &unicam_image_formats[0];
> > > +             pix->pixelformat = fmtinfo->fourcc;
> > > +     }
> > > +
> > > +     unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> > > +
> > > +     if (pix->field == V4L2_FIELD_ANY)
> > > +             pix->field = V4L2_FIELD_NONE;
> > > +
> > > +     return fmtinfo;
> > > +}
> > > +
> > > +static int unicam_try_fmt_vid(struct file *file, void *priv,
> > > +                           struct v4l2_format *f)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +
> > > +     __unicam_try_fmt_vid(node, &f->fmt.pix);
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_s_fmt_vid(struct file *file, void *priv,
> > > +                         struct v4l2_format *f)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +
> > > +     if (vb2_is_busy(&node->buffer_queue))
> > > +             return -EBUSY;
> > > +
> > > +     node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> > > +     node->fmt = *f;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> > > +                             struct v4l2_fmtdesc *f)
> > > +{
> > > +     unsigned int i, index;
> > > +
> > > +     for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> > > +             if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
> >
> > Do we want to allow mbus_code filtering for metadata ? There's a
> > 1-to-1 relationship between mbus codes and pixel formats
> >
> > > +                     continue;
> > > +             if (!unicam_meta_formats[i].metadata_fmt)
> > > +                     continue;
> >
> > How can this be false if we're iterating on unicam_meta_formats[] ?
> >
> > > +
> > > +             if (index == f->index) {
> > > +                     f->pixelformat = unicam_meta_formats[i].fourcc;
> > > +                     f->type = V4L2_BUF_TYPE_META_CAPTURE;
> > > +                     return 0;
> > > +             }
> > > +             index++;
> > > +     }
> > > +
> > > +     return -EINVAL;
> > > +}
> > > +
> > > +static int unicam_g_fmt_meta(struct file *file, void *priv,
> > > +                          struct v4l2_format *f)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +
> > > +     f->fmt.meta = node->fmt.fmt.meta;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct unicam_format_info *
> > > +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> > > +{
> > > +     const struct unicam_format_info *fmtinfo;
> > > +
> > > +     /*
> > > +      * Default to the first format if the requested pixel format code isn't
> > > +      * supported.
> > > +      */
> > > +     fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> > > +                                            UNICAM_SD_PAD_SOURCE_METADATA);
> > > +     if (!fmtinfo) {
> > > +             fmtinfo = &unicam_meta_formats[0];
> > > +             meta->dataformat = fmtinfo->fourcc;
> > > +     }
> > > +
> > > +     unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> > > +
> > > +     return fmtinfo;
> > > +}
> > > +
> > > +static int unicam_try_fmt_meta(struct file *file, void *priv,
> > > +                            struct v4l2_format *f)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +
> > > +     __unicam_try_fmt_vid(node, &f->fmt.pix);
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_s_fmt_meta(struct file *file, void *priv,
> > > +                          struct v4l2_format *f)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +
> > > +     if (vb2_is_busy(&node->buffer_queue))
> > > +             return -EBUSY;
> > > +
> > > +     node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> > > +     node->fmt = *f;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_enum_framesizes(struct file *file, void *fh,
> > > +                               struct v4l2_frmsizeenum *fsize)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +     int ret = -EINVAL;
> > > +
> > > +     if (fsize->index > 0)
> > > +             return ret;
> > > +
> > > +     if (is_image_node(node)) {
> > > +             if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > > +                                               UNICAM_SD_PAD_SOURCE_IMAGE))
> > > +                     return ret;
> > > +
> > > +             fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> > > +             fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> > > +             fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> > > +             fsize->stepwise.step_width = 1;
> > > +             fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> > > +             fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> > > +             fsize->stepwise.step_height = 1;
> > > +     } else {
> > > +             if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> > > +                                               UNICAM_SD_PAD_SOURCE_METADATA))
> > > +                     return ret;
> > > +
> > Isn't this V4L2_FRMSIZE_TYPE_STEPWISE as well ?
> >
> > > +             fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> > > +             fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> > > +             fsize->stepwise.step_width = 1;
> > > +             fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> > > +             fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> > > +             fsize->stepwise.step_height = 1;
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_log_status(struct file *file, void *fh)
> > > +{
> > > +     struct unicam_node *node = video_drvdata(file);
> > > +     struct unicam_device *unicam = node->dev;
> > > +     u32 reg;
> > > +
> > > +     /* status for sub devices */
> > > +     v4l2_device_call_all(&unicam->v4l2_dev, 0, core, log_status);
> > > +
> > > +     dev_info(unicam->dev, "-----Receiver status-----\n");
> > > +     dev_info(unicam->dev, "V4L2 width/height:   %ux%u\n",
> > > +              node->fmt.fmt.pix.width, node->fmt.fmt.pix.height);
> > > +     dev_info(unicam->dev, "Mediabus format:     %08x\n",
> > > +              node->fmtinfo->code);
> > > +     dev_info(unicam->dev, "V4L2 format:         %08x\n",
> > > +              node->fmt.fmt.pix.pixelformat);
> > > +     reg = unicam_reg_read(unicam, UNICAM_IPIPE);
> > > +     dev_info(unicam->dev, "Unpacking/packing:   %u / %u\n",
> > > +              unicam_get_field(reg, UNICAM_PUM_MASK),
> > > +              unicam_get_field(reg, UNICAM_PPM_MASK));
> > > +     dev_info(unicam->dev, "----Live data----\n");
> > > +     dev_info(unicam->dev, "Programmed stride:   %4u\n",
> > > +              unicam_reg_read(unicam, UNICAM_IBLS));
> > > +     dev_info(unicam->dev, "Detected resolution: %ux%u\n",
> > > +              unicam_reg_read(unicam, UNICAM_IHSTA),
> > > +              unicam_reg_read(unicam, UNICAM_IVSTA));
> > > +     dev_info(unicam->dev, "Write pointer:       %08x\n",
> > > +              unicam_reg_read(unicam, UNICAM_IBWP));
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int unicam_subscribe_event(struct v4l2_fh *fh,
> > > +                               const struct v4l2_event_subscription *sub)
> > > +{
> > > +     switch (sub->type) {
> > > +     case V4L2_EVENT_FRAME_SYNC:
> > > +             return v4l2_event_subscribe(fh, sub, 2, NULL);
> > > +     default:
> > > +             return -EINVAL;
> > > +     }
> > > +}
> > > +
> > > +static const struct v4l2_ioctl_ops unicam_ioctl_ops = {
> > > +     .vidioc_querycap                = unicam_querycap,
> > > +
> > > +     .vidioc_enum_fmt_vid_cap        = unicam_enum_fmt_vid,
> > > +     .vidioc_g_fmt_vid_cap           = unicam_g_fmt_vid,
> > > +     .vidioc_try_fmt_vid_cap         = unicam_try_fmt_vid,
> > > +     .vidioc_s_fmt_vid_cap           = unicam_s_fmt_vid,
> > > +
> > > +     .vidioc_enum_fmt_meta_cap       = unicam_enum_fmt_meta,
> > > +     .vidioc_g_fmt_meta_cap          = unicam_g_fmt_meta,
> > > +     .vidioc_try_fmt_meta_cap        = unicam_try_fmt_meta,
> > > +     .vidioc_s_fmt_meta_cap          = unicam_s_fmt_meta,
> > > +
> > > +     .vidioc_enum_framesizes         = unicam_enum_framesizes,
> > > +
> > > +     .vidioc_reqbufs                 = vb2_ioctl_reqbufs,
> > > +     .vidioc_create_bufs             = vb2_ioctl_create_bufs,
> > > +     .vidioc_prepare_buf             = vb2_ioctl_prepare_buf,
> > > +     .vidioc_querybuf                = vb2_ioctl_querybuf,
> > > +     .vidioc_qbuf                    = vb2_ioctl_qbuf,
> > > +     .vidioc_dqbuf                   = vb2_ioctl_dqbuf,
> > > +     .vidioc_expbuf                  = vb2_ioctl_expbuf,
> > > +     .vidioc_streamon                = vb2_ioctl_streamon,
> > > +     .vidioc_streamoff               = vb2_ioctl_streamoff,
> > > +
> > > +     .vidioc_log_status              = unicam_log_status,
> > > +     .vidioc_subscribe_event         = unicam_subscribe_event,
> > > +     .vidioc_unsubscribe_event       = v4l2_event_unsubscribe,
> > > +};
> > > +
> > > +/* unicam capture driver file operations */
> > > +static const struct v4l2_file_operations unicam_fops = {
> > > +     .owner          = THIS_MODULE,
> > > +     .open           = v4l2_fh_open,
> > > +     .release        = vb2_fop_release,
> > > +     .poll           = vb2_fop_poll,
> > > +     .unlocked_ioctl = video_ioctl2,
> > > +     .mmap           = vb2_fop_mmap,
> > > +};
> > > +
> > > +static int unicam_video_link_validate(struct media_link *link)
> > > +{
> > > +     struct video_device *vdev =
> > > +             media_entity_to_video_device(link->sink->entity);
> > > +     struct v4l2_subdev *sd =
> > > +             media_entity_to_v4l2_subdev(link->source->entity);
> > > +     struct unicam_node *node = video_get_drvdata(vdev);
> > > +     const u32 pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                   : UNICAM_SD_PAD_SOURCE_METADATA;
> > > +     const struct v4l2_mbus_framefmt *format;
> > > +     struct v4l2_subdev_state *state;
> > > +     int ret = 0;
> > > +
> > > +     state = v4l2_subdev_lock_and_get_active_state(sd);
> > > +
> > > +     format = v4l2_subdev_state_get_format(state, pad, 0);
> > > +     if (!format) {
> > > +             ret = -EINVAL;
> > > +             goto out;
> > > +     }
> > > +
> > > +     if (is_image_node(node)) {
> > > +             const struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> > > +
> > > +             if (node->fmtinfo->code != format->code ||
> > > +                 fmt->height != format->height ||
> > > +                 fmt->width != format->width ||
> > > +                 fmt->field != format->field) {
> > > +                     dev_dbg(node->dev->dev,
> > > +                             "image: (%u x %u) 0x%08x %s != (%u x %u) 0x%08x %s\n",
> > > +                             fmt->width, fmt->height, node->fmtinfo->code,
> > > +                             v4l2_field_names[fmt->field],
> > > +                             format->width, format->height, format->code,
> > > +                             v4l2_field_names[format->field]);
> > > +                     ret = -EPIPE;
> > > +             };
> >
> > No need for ; here and in the next loop
> >
> > > +     } else {
> > > +             const struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> > > +
> > > +             if (node->fmtinfo->code != format->code ||
> > > +                 fmt->height != format->height ||
> > > +                 fmt->width != format->width) {
> > > +                     dev_dbg(node->dev->dev,
> > > +                             "meta: (%u x %u) 0x%04x != (%u x %u) 0x%04x\n",
> > > +                             fmt->width, fmt->height, node->fmtinfo->code,
> > > +                             format->width, format->height, format->code);
> > > +                     ret = -EPIPE;
> > > +             };
> > > +     }
> > > +
> > > +out:
> > > +     v4l2_subdev_unlock_state(state);
> > > +     return ret;
> > > +}
> > > +
> > > +static const struct media_entity_operations unicam_video_media_ops = {
> > > +     .link_validate = unicam_video_link_validate,
> > > +};
> > > +
> > > +static void unicam_node_release(struct video_device *vdev)
> > > +{
> > > +     struct unicam_node *node = video_get_drvdata(vdev);
> > > +
> > > +     unicam_put(node->dev);
> > > +}
> > > +
> > > +static void unicam_set_default_format(struct unicam_node *node)
> > > +{
> > > +     if (is_image_node(node)) {
> > > +             struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> > > +
> > > +             node->fmtinfo = &unicam_image_formats[0];
> > > +             node->fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> > > +
> > > +             v4l2_fill_pix_format(fmt, &unicam_default_image_format);
> > > +             fmt->pixelformat = node->fmtinfo->fourcc;
> > > +             unicam_calc_image_size_bpl(node->dev, node->fmtinfo, fmt);
> > > +     } else {
> > > +             struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> > > +
> > > +             node->fmtinfo = &unicam_meta_formats[0];
> > > +             node->fmt.type = V4L2_BUF_TYPE_META_CAPTURE;
> > > +
> > > +             fmt->dataformat = node->fmtinfo->fourcc;
> > > +             fmt->width = unicam_default_meta_format.width;
> > > +             fmt->height = unicam_default_meta_format.height;
> > > +             unicam_calc_meta_size_bpl(node->dev, node->fmtinfo, fmt);
> > > +     }
> > > +}
> > > +
> > > +static int unicam_register_node(struct unicam_device *unicam,
> > > +                             enum unicam_node_type type)
> > > +{
> > > +     const u32 pad_index = type == UNICAM_IMAGE_NODE
> > > +                         ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > +                         : UNICAM_SD_PAD_SOURCE_METADATA;
> > > +     struct unicam_node *node = &unicam->node[type];
> > > +     struct video_device *vdev = &node->video_dev;
> > > +     struct vb2_queue *q = &node->buffer_queue;
> > > +     int ret;
> > > +
> > > +     node->dev = unicam_get(unicam);
> > > +     node->id = type;
> > > +
> > > +     spin_lock_init(&node->dma_queue_lock);
> > > +     mutex_init(&node->lock);
> > > +
> > > +     INIT_LIST_HEAD(&node->dma_queue);
> > > +
> > > +     /* Initialize the videobuf2 queue. */
> > > +     q->type = type == UNICAM_IMAGE_NODE ? V4L2_BUF_TYPE_VIDEO_CAPTURE
> > > +                                         : V4L2_BUF_TYPE_META_CAPTURE;
> > > +     q->io_modes = VB2_MMAP | VB2_DMABUF;
> > > +     q->drv_priv = node;
> > > +     q->ops = &unicam_video_qops;
> > > +     q->mem_ops = &vb2_dma_contig_memops;
> > > +     q->buf_struct_size = sizeof(struct unicam_buffer);
> > > +     q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> > > +     q->lock = &node->lock;
> > > +     q->min_queued_buffers = 1;
> > > +     q->dev = unicam->dev;
> > > +
> > > +     ret = vb2_queue_init(q);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "vb2_queue_init() failed\n");
> > > +             goto err_unicam_put;
> > > +     }
> > > +
> > > +     /* Initialize the video device. */
> > > +     vdev->release = unicam_node_release;
> > > +     vdev->fops = &unicam_fops;
> > > +     vdev->ioctl_ops = &unicam_ioctl_ops;
> > > +     vdev->v4l2_dev = &unicam->v4l2_dev;
> > > +     vdev->vfl_dir = VFL_DIR_RX;
> > > +     vdev->queue = q;
> > > +     vdev->lock = &node->lock;
> > > +     vdev->device_caps = type == UNICAM_IMAGE_NODE
> > > +                       ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_META_CAPTURE;
> > > +     vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
> > > +     vdev->entity.ops = &unicam_video_media_ops;
> > > +
> > > +     snprintf(vdev->name, sizeof(vdev->name), "%s-%s", UNICAM_MODULE_NAME,
> > > +              type == UNICAM_IMAGE_NODE ? "image" : "embedded");
> > > +
> > > +     video_set_drvdata(vdev, node);
> > > +
> > > +     if (type == UNICAM_IMAGE_NODE)
> > > +             vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
> > > +
> > > +     node->pad.flags = MEDIA_PAD_FL_SINK;
> > > +
> > > +     ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
> > > +     if (ret)
> > > +             goto err_unicam_put;
> > > +
> > > +     node->dummy_buf.size = UNICAM_DUMMY_BUF_SIZE;
> > > +     node->dummy_buf_cpu_addr = dma_alloc_coherent(unicam->dev,
> > > +                                                   node->dummy_buf.size,
> > > +                                                   &node->dummy_buf.dma_addr,
> > > +                                                   GFP_KERNEL);
> > > +     if (!node->dummy_buf_cpu_addr) {
> > > +             dev_err(unicam->dev, "Unable to allocate dummy buffer.\n");
> > > +             ret = -ENOMEM;
> > > +             goto err_entity_cleanup;
> > > +     }
> > > +
> > > +     unicam_set_default_format(node);
> > > +
> > > +     ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "Unable to register video device %s\n",
> > > +                     vdev->name);
> > > +             goto err_dma_free;
> > > +     }
> > > +
> > > +     node->registered = true;
> > > +
> > > +     ret = media_create_pad_link(&unicam->subdev.sd.entity,
> > > +                                 pad_index,
> > > +                                 &node->video_dev.entity,
> > > +                                 0,
> > > +                                 MEDIA_LNK_FL_ENABLED |
> > > +                                 MEDIA_LNK_FL_IMMUTABLE);
> > > +     if (ret) {
> > > +             /*
> > > +              * No need for cleanup, the caller will unregister the
> > > +              * video device, which will drop the reference on the
> > > +              * device and trigger the cleanup.
> > > +              */
> > > +             dev_err(unicam->dev, "Unable to create pad link for %s\n",
> > > +                     unicam->sensor.subdev->name);
> > > +             return ret;
> > > +     }
> > > +
> > > +     return 0;
> > > +
> > > +err_dma_free:
> > > +     dma_free_coherent(unicam->dev, node->dummy_buf.size,
> > > +                       node->dummy_buf_cpu_addr,
> > > +                       node->dummy_buf.dma_addr);
> > > +err_entity_cleanup:
> > > +     media_entity_cleanup(&vdev->entity);
> > > +err_unicam_put:
> > > +     unicam_put(unicam);
> > > +     return ret;
> > > +}
> > > +
> > > +static void unicam_unregister_nodes(struct unicam_device *unicam)
> > > +{
> > > +     unsigned int i;
> > > +
> > > +     for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +             struct unicam_node *node = &unicam->node[i];
> > > +
> > > +             if (node->dummy_buf_cpu_addr)
> > > +                     dma_free_coherent(unicam->dev, node->dummy_buf.size,
> > > +                                       node->dummy_buf_cpu_addr,
> > > +                                       node->dummy_buf.dma_addr);
> > > +
> > > +             if (node->registered) {
> > > +                     video_unregister_device(&node->video_dev);
> > > +                     node->registered = false;
> > > +             }
> > > +     }
> > > +}
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + * Power management
> > > + */
> > > +
> > > +static int unicam_runtime_resume(struct device *dev)
> > > +{
> > > +     struct unicam_device *unicam = dev_get_drvdata(dev);
> > > +     int ret;
> > > +
> > > +     ret = clk_set_min_rate(unicam->vpu_clock, UNICAM_MIN_VPU_CLOCK_RATE);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "failed to set up VPU clock\n");
> > > +             return ret;
> > > +     }
> >
> > Same question as above, shouldn't this be an 'assigned-clock-rates in
> > dts ?
> >
> > > +
> > > +     ret = clk_prepare_enable(unicam->vpu_clock);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "Failed to enable VPU clock: %d\n", ret);
> > > +             goto err_vpu_clock;
> > > +     }
> > > +
> > > +     ret = clk_set_rate(unicam->clock, 100 * 1000 * 1000);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "failed to set up CSI clock\n");
> > > +             goto err_vpu_prepare;
> > > +     }
> >
> > same question
> >
> > > +
> > > +     ret = clk_prepare_enable(unicam->clock);
> > > +     if (ret) {
> > > +             dev_err(unicam->dev, "Failed to enable CSI clock: %d\n", ret);
> > > +             goto err_vpu_prepare;
> >
> > Do you need to 'unset' the rate as done for the VPU clock ?
> >
> > > +     }
> > > +
> > > +     return 0;
> > > +
> > > +err_vpu_prepare:
> > > +     clk_disable_unprepare(unicam->vpu_clock);
> > > +err_vpu_clock:
> > > +     if (clk_set_min_rate(unicam->vpu_clock, 0))
> > > +             dev_err(unicam->dev, "failed to reset the VPU clock\n");
> > > +
> > > +     return ret;
> > > +}
> > > +
> > > +static int unicam_runtime_suspend(struct device *dev)
> > > +{
> > > +     struct unicam_device *unicam = dev_get_drvdata(dev);
> > > +
> > > +     clk_disable_unprepare(unicam->clock);
> >
> > (continuing  with the above question: probably not, as the clock is
> > not 'unset' neither here)
> >
> > The rest looks good, nice to see this progressing!
> >
> > Thanks
> >   j
> >
> <snip>

Laurent Pinchart March 16, 2024, 11:54 p.m. UTC | #6

Hi Dave,

On Tue, Mar 05, 2024 at 02:56:29PM +0000, Dave Stevenson wrote:
> On Mon, 4 Mar 2024 at 19:51, Laurent Pinchart wrote:
> > On Mon, Mar 04, 2024 at 06:12:21PM +0100, Jacopo Mondi wrote:
> > > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > > From: Dave Stevenson <[e-mail]>
> > > >
> > > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > > It is represented as two video device nodes: unicam-image and
> > > > unicam-embedded which are connected to an internal subdev (named
> > > > unicam-subdev) in order to manage streams routing.
> > > >
> > > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > > > ---
> > > > Changes since v5:
> > > >
> > > > - Move to drivers/media/platform/broadcom/
> > > > - Port to the upstream V4L2 streams API
> > > > - Rebase on latest metadata API proposal
> > > > - Add missing error message
> > > > - Drop unneeded documentation block for unicam_isr()
> > > > - Drop unneeded dev_dbg() and dev_err() messages
> > > > - Drop unneeded streams_mask and fmt checks
> > > > - Drop unused unicam_sd_pad_is_sink()
> > > > - Drop unneeded includes
> > > > - Drop v4l2_ctrl_subscribe_event() call
> > > > - Use pm_runtime_resume_and_get()
> > > > - Indentation and line wrap fixes
> > > > - Let the framework set bus_info
> > > > - Use v4l2_fwnode_endpoint_parse()
> > > > - Fix media device cleanup
> > > > - Drop lane reordering checks
> > > > - Fix subdev state locking
> > > > - Drop extra debug messages
> > > > - Move clock handling to runtime PM handlers
> > > > - Reorder functions
> > > > - Rename init functions for more clarity
> > > > - Initialize runtime PM earlier
> > > > - Clarify error messages
> > > > - Simplify subdev init with local variable
> > > > - Fix subdev cleanup
> > > > - Fix typos and indentation
> > > > - Don't initialize local variables needlessly
> > > > - Simplify num lanes check
> > > > - Fix metadata handling in subdev set_fmt
> > > > - Drop manual fallback to .s_stream()
> > > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > > - Simplify unicam_set_default_format()
> > > > - Fix default format settings
> > > > - Add busy check in unicam_s_fmt_meta()
> > > > - Add missing \n at end of format strings
> > > > - Fix metadata handling in subdev set_fmt
> > > > - Fix locking when starting streaming
> > > > - Return buffers from start streaming fails
> > > > - Fix format validation for metadata node
> > > > - Use video_device_pipeline_{start,stop}() helpers
> > > > - Simplify format enumeration
> > > > - Drop unset variable
> > > > - Update MAINTAINERS entry
> > > > - Update to the upstream v4l2_async_nf API
> > > > - Update to the latest subdev routing API
> > > > - Update to the latest subdev state API
> > > > - Move from subdev .init_cfg() to .init_state()
> > > > - Update to the latest videobuf2 API
> > > > - Fix v4l2_subdev_enable_streams() error check
> > > > - Use correct pad for the connected subdev
> > > > - Return buffers to vb2 when start streaming fails
> > > > - Improve debugging in start streaming handler
> > > > - Simplify DMA address management
> > > > - Drop comment about bcm2835-camera driver
> > > > - Clarify comments that explain min/max sizes
> > > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > > - Drop unneeded local variables
> > > > - Rename image-related constants and functions
> > > > - Turn unicam_fmt.metadata_fmt into bool
> > > > - Rename unicam_fmt to unicam_format_info
> > > > - Rename unicam_format_info variables to fmtinfo
> > > > - Rename unicam_node.v_fmt to fmt
> > > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > > - Make metadata formats line-based
> > > > - Validate format on metadata video device
> > > > - Add Co-devlopped-by tags
> > > >
> > > > Changes since v3:
> > > >
> > > > - Add the vendor prefix for DT name
> > > > - Use the reg-names in DT parsing
> > > > - Remove MAINTAINERS entry
> > > >
> > > > Changes since v2:
> > > >
> > > > - Change code organization
> > > > - Remove unused variables
> > > > - Correct the fmt_meta functions
> > > > - Rewrite the start/stop streaming
> > > >   - You can now start the image node alone, but not the metadata one
> > > >   - The buffers are allocated per-node
> > > >   - only the required stream is started, if the route exists and is
> > > >     enabled
> > > > - Prefix the macros with UNICAM_ to not have too generic names
> > > > - Drop colorspace support
> > > >
> > > > Changes since v1:
> > > >
> > > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > > ---
> > > >  MAINTAINERS                                   |    1 +
> > > >  drivers/media/platform/Kconfig                |    1 +
> > > >  drivers/media/platform/Makefile               |    1 +
> > > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > > >  7 files changed, 2891 insertions(+)
> > > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> >
> > [snip]
> >
> > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > new file mode 100644
> > > > index 000000000000..716c89b8a217
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > @@ -0,0 +1,2607 @@

[snip]

> > > > +/* -----------------------------------------------------------------------------
> > > > + * Videobuf2 queue operations
> > > > + */
> > > > +
> > > > +static int unicam_queue_setup(struct vb2_queue *vq,
> > > > +                         unsigned int *nbuffers,
> > > > +                         unsigned int *nplanes,
> > > > +                         unsigned int sizes[],
> > > > +                         struct device *alloc_devs[])
> > > > +{
> > > > +   struct unicam_node *node = vb2_get_drv_priv(vq);
> > > > +   u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> > > > +            : node->fmt.fmt.meta.buffersize;
> > > > +
> > > > +   if (vq->num_buffers + *nbuffers < 3)
> > >
> > > Why 3 ? Are these dummies ?
> >
> > This may be a remnant of old code. Dave, Naush, any comment ?
> 
> I suspect this is legacy.
> Originally the driver would only release the buffer at the frame end
> when it had a new one to switch to. Naush updated with the dummy
> buffer so in theory you can run with 1 buffer, but this min number of
> buffers probably didn't get reduced.
> Then again it may have been a misunderstanding of the framework, as
> struct vb2_queue min_buffers_needed should set the minimum.

I'll drop this.

> > > > +           *nbuffers = 3 - vq->num_buffers;
> > > > +
> > > > +   if (*nplanes) {
> > > > +           if (sizes[0] < size) {
> > > > +                   dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> > > > +                           sizes[0], size);
> > > > +                   return -EINVAL;
> > > > +           }
> > > > +           size = sizes[0];
> > > > +   }
> > > > +
> > > > +   *nplanes = 1;
> > > > +   sizes[0] = size;
> > > > +
> > > > +   return 0;
> > > > +}

[snip]

> > > > +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> > > > +{
> > > > +   struct unicam_node *node = vb2_get_drv_priv(vq);
> > > > +   struct unicam_device *unicam = node->dev;
> > > > +   struct v4l2_subdev_state *state;
> > > > +   struct unicam_buffer *buf;
> > > > +   unsigned long flags;
> > > > +   int ret;
> > > > +   u32 pad, stream;
> > > > +   u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > > > +                                        : UNICAM_SD_PAD_SOURCE_METADATA;
> > > > +
> > > > +   /* Look for the route for the given pad and stream. */
> > > > +   state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> > > > +   ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > > > +                                               remote_pad, 0,
> > > > +                                               &pad, &stream);
> > > > +   v4l2_subdev_unlock_state(state);
> > > > +
> > > > +   if (ret)
> > > > +           goto err_return_buffers;
> > > > +
> > > > +   dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> > > > +           unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> > > > +           is_metadata_node(node) ? "metadata" : "image");
> > > > +
> > > > +   /* The metadata node can't be started alone. */
> > > > +   if (is_metadata_node(node)) {
> > > > +           if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> > >
> > > Does it mean the metadata node has to be started second, or should
> > > this be made a nop and the metadata node gets started once the image
> > > node is started too ? I'm fine with the constraint of having the
> > > metadata node being started second fwiw
> >
> > I think it would be nice to change this indeed. Dave, Naush, any
> > objection ?
> 
> See previous email.
> 
> > > > +                   dev_err(unicam->dev,
> > > > +                           "Can't start metadata without image\n");
> > > > +                   ret = -EINVAL;
> > > > +                   goto err_return_buffers;
> > > > +           }
> > > > +
> > > > +           spin_lock_irqsave(&node->dma_queue_lock, flags);
> > > > +           buf = list_first_entry(&node->dma_queue,
> > > > +                                  struct unicam_buffer, list);
> > > > +           dev_dbg(unicam->dev, "buffer %p\n", buf);
> > >
> > > Is this useful ?
> >
> > Probably not much. I'll drop it.
> >
> > > > +           node->cur_frm = buf;
> > > > +           node->next_frm = buf;
> > > > +           list_del(&buf->list);
> > > > +           spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > > > +
> > > > +           unicam_start_metadata(unicam, buf);
> > > > +           node->streaming = true;
> > > > +           return 0;
> > > > +   }
> > > > +
> > > > +   ret = pm_runtime_resume_and_get(unicam->dev);
> > > > +   if (ret < 0) {
> > > > +           dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> > > > +           goto err_return_buffers;
> > > > +   }
> > > > +
> > > > +   ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> > > > +   if (ret < 0) {
> > > > +           dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> > >
> > > Isn't this an err ?
> >
> > The main cause of failure is a pipeline validation error, triggered by
> > userspace, hence the debug level.
> >
> > > > +           goto err_pm_put;
> > > > +   }
> > > > +
> > > > +   spin_lock_irqsave(&node->dma_queue_lock, flags);
> > > > +   buf = list_first_entry(&node->dma_queue,
> > > > +                          struct unicam_buffer, list);
> > > > +   dev_dbg(unicam->dev, "buffer %p\n", buf);
> > > > +   node->cur_frm = buf;
> > > > +   node->next_frm = buf;
> > > > +   list_del(&buf->list);
> > > > +   spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > > > +
> > > > +   unicam_start_rx(unicam, buf);
> > > > +
> > > > +   ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> > >
> > > A bit confused by the API here, shouldn't we also do this for embedded
> > > data ?
> >
> > Not here, as the two streams go over different pads, but likely above,
> > as part of the change you proposed regarding stream start on the
> > metadata device. I'll wait for Dave and Naush to reply, and I'll rework
> > this function.
> 
> I haven't read enough on the streams API, or what this implementation
> looks like.
> 
> There's no sensible way for a sensor to start embedded or other
> metadata without image data, so starting the image node would seem to
> be the main trigger for anything. I'm also assuming we don't support
> enabling additional multiplexed streams once the pipeline is already
> running, so that would seem to determine some of the sequencing.

The API allows enabling and disabling streams independently, which is a
useful feature for instance when multiple cameras are multiplexed over a
single CSI-2 link with virtual channels. For image + embedded data, not
only is the sequencing fixed (as you mentioned, the sensor can't send
embedded data without image data), but synchronization is also
important.

> > > > +   if (ret < 0) {
> > > > +           dev_err(unicam->dev, "stream on failed in subdev\n");
> > > > +           goto error_pipeline;
> > > > +   }
> > > > +
> > > > +   node->streaming = true;
> > > > +
> > > > +   return 0;
> > > > +
> > > > +error_pipeline:
> > > > +   video_device_pipeline_stop(&node->video_dev);
> > > > +err_pm_put:
> > > > +   pm_runtime_put_sync(unicam->dev);
> > > > +err_return_buffers:
> > > > +   unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> > > > +   return ret;
> > > > +}

[snip]

Naushir Patuck March 20, 2024, 12:30 p.m. UTC | #7

Hi Laurent,

Thank you for submitting this!

On Fri, 1 Mar 2024 at 21:32, Laurent Pinchart
<[e-mail]> wrote:
>
> From: Dave Stevenson <[e-mail]>
>
> Add a driver for the Unicam camera receiver block on BCM283x processors.
> It is represented as two video device nodes: unicam-image and
> unicam-embedded which are connected to an internal subdev (named
> unicam-subdev) in order to manage streams routing.
>
> Signed-off-by: Dave Stevenson <[e-mail]>
> Co-developed-by: Naushir Patuck <[e-mail]>
> Signed-off-by: Naushir Patuck <[e-mail]>
> Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> Co-developed-by: Laurent Pinchart <[e-mail]>
> Signed-off-by: Laurent Pinchart <[e-mail]>
> ---
> Changes since v5:
>
> - Move to drivers/media/platform/broadcom/
> - Port to the upstream V4L2 streams API
> - Rebase on latest metadata API proposal
> - Add missing error message
> - Drop unneeded documentation block for unicam_isr()
> - Drop unneeded dev_dbg() and dev_err() messages
> - Drop unneeded streams_mask and fmt checks
> - Drop unused unicam_sd_pad_is_sink()
> - Drop unneeded includes
> - Drop v4l2_ctrl_subscribe_event() call
> - Use pm_runtime_resume_and_get()
> - Indentation and line wrap fixes
> - Let the framework set bus_info
> - Use v4l2_fwnode_endpoint_parse()
> - Fix media device cleanup
> - Drop lane reordering checks
> - Fix subdev state locking
> - Drop extra debug messages
> - Move clock handling to runtime PM handlers
> - Reorder functions
> - Rename init functions for more clarity
> - Initialize runtime PM earlier
> - Clarify error messages
> - Simplify subdev init with local variable
> - Fix subdev cleanup
> - Fix typos and indentation
> - Don't initialize local variables needlessly
> - Simplify num lanes check
> - Fix metadata handling in subdev set_fmt
> - Drop manual fallback to .s_stream()
> - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> - Simplify unicam_set_default_format()
> - Fix default format settings
> - Add busy check in unicam_s_fmt_meta()
> - Add missing \n at end of format strings
> - Fix metadata handling in subdev set_fmt
> - Fix locking when starting streaming
> - Return buffers from start streaming fails
> - Fix format validation for metadata node
> - Use video_device_pipeline_{start,stop}() helpers
> - Simplify format enumeration
> - Drop unset variable
> - Update MAINTAINERS entry
> - Update to the upstream v4l2_async_nf API
> - Update to the latest subdev routing API
> - Update to the latest subdev state API
> - Move from subdev .init_cfg() to .init_state()
> - Update to the latest videobuf2 API
> - Fix v4l2_subdev_enable_streams() error check
> - Use correct pad for the connected subdev
> - Return buffers to vb2 when start streaming fails
> - Improve debugging in start streaming handler
> - Simplify DMA address management
> - Drop comment about bcm2835-camera driver
> - Clarify comments that explain min/max sizes
> - Pass v4l2_pix_format to unicam_try_fmt()
> - Drop unneeded local variables
> - Rename image-related constants and functions
> - Turn unicam_fmt.metadata_fmt into bool
> - Rename unicam_fmt to unicam_format_info
> - Rename unicam_format_info variables to fmtinfo
> - Rename unicam_node.v_fmt to fmt
> - Add metadata formats for RAW10, RAW12 and RAW14
> - Make metadata formats line-based
> - Validate format on metadata video device
> - Add Co-devlopped-by tags
>
> Changes since v3:
>
> - Add the vendor prefix for DT name
> - Use the reg-names in DT parsing
> - Remove MAINTAINERS entry
>
> Changes since v2:
>
> - Change code organization
> - Remove unused variables
> - Correct the fmt_meta functions
> - Rewrite the start/stop streaming
>   - You can now start the image node alone, but not the metadata one
>   - The buffers are allocated per-node
>   - only the required stream is started, if the route exists and is
>     enabled
> - Prefix the macros with UNICAM_ to not have too generic names
> - Drop colorspace support
>
> Changes since v1:
>
> - Replace the unicam_{info,debug,error} macros with dev_*()
> ---
>  MAINTAINERS                                   |    1 +
>  drivers/media/platform/Kconfig                |    1 +
>  drivers/media/platform/Makefile               |    1 +
>  drivers/media/platform/broadcom/Kconfig       |   23 +
>  drivers/media/platform/broadcom/Makefile      |    3 +
>  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
>  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
>  7 files changed, 2891 insertions(+)
>  create mode 100644 drivers/media/platform/broadcom/Kconfig
>  create mode 100644 drivers/media/platform/broadcom/Makefile
>  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
>  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e50a59654e6e..cc350729f467 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4002,6 +4002,7 @@ M:        Raspberry Pi Kernel Maintenance <[e-mail]>
>  L:     [e-mail]
>  S:     Maintained
>  F:     Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> +F:     drivers/media/platform/bcm2835/
>
>  BROADCOM BCM47XX MIPS ARCHITECTURE
>  M:     Hauke Mehrtens <[e-mail]>
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index 91e54215de3a..2d79bfc68c15 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
>  source "drivers/media/platform/amphion/Kconfig"
>  source "drivers/media/platform/aspeed/Kconfig"
>  source "drivers/media/platform/atmel/Kconfig"
> +source "drivers/media/platform/broadcom/Kconfig"
>  source "drivers/media/platform/cadence/Kconfig"
>  source "drivers/media/platform/chips-media/Kconfig"
>  source "drivers/media/platform/intel/Kconfig"
> diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> index 3296ec1ebe16..da17301f7439 100644
> --- a/drivers/media/platform/Makefile
> +++ b/drivers/media/platform/Makefile
> @@ -10,6 +10,7 @@ obj-y += amlogic/
>  obj-y += amphion/
>  obj-y += aspeed/
>  obj-y += atmel/
> +obj-y += broadcom/
>  obj-y += cadence/
>  obj-y += chips-media/
>  obj-y += intel/
> diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> new file mode 100644
> index 000000000000..cc2c9afcc948
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/Kconfig
> @@ -0,0 +1,23 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +config VIDEO_BCM2835_UNICAM
> +       tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> +       depends on ARCH_BCM2835 || COMPILE_TEST
> +       depends on PM
> +       depends on VIDEO_DEV
> +       select MEDIA_CONTROLLER
> +       select V4L2_FWNODE
> +       select VIDEO_V4L2_SUBDEV_API
> +       select VIDEOBUF2_DMA_CONTIG
> +       help
> +         Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> +         This is a V4L2 driver that controls the CSI-2 receiver directly,
> +         independently from the VC4 firmware.
> +
> +         This driver is mutually exclusive with the use of bcm2835-camera. The
> +         firmware will disable all access to the peripheral from within the
> +         firmware if it finds a DT node using it, and bcm2835-camera will
> +         therefore fail to probe.
> +
> +         To compile this driver as a module, choose M here. The module will be
> +         called bcm2835-unicam.
> diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> new file mode 100644
> index 000000000000..03d2045aba2e
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> new file mode 100644
> index 000000000000..84775fd2fac5
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> @@ -0,0 +1,255 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +/*
> + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> + * Dave Stevenson <[e-mail]>
> + */
> +
> +#ifndef VC4_REGS_UNICAM_H
> +#define VC4_REGS_UNICAM_H
> +
> +#include <linux/bits.h>
> +
> +/*
> + * The following values are taken from files found within the code drop
> + * made by Broadcom for the BCM21553 Graphics Driver, predominantly in
> + * brcm_usrlib/dag/vmcsx/vcinclude/hardware_vc4.h.
> + * They have been modified to be only the register offset.
> + */
> +#define UNICAM_CTRL            0x000
> +#define UNICAM_STA             0x004
> +#define UNICAM_ANA             0x008
> +#define UNICAM_PRI             0x00c
> +#define UNICAM_CLK             0x010
> +#define UNICAM_CLT             0x014
> +#define UNICAM_DAT0            0x018
> +#define UNICAM_DAT1            0x01c
> +#define UNICAM_DAT2            0x020
> +#define UNICAM_DAT3            0x024
> +#define UNICAM_DLT             0x028
> +#define UNICAM_CMP0            0x02c
> +#define UNICAM_CMP1            0x030
> +#define UNICAM_CAP0            0x034
> +#define UNICAM_CAP1            0x038
> +#define UNICAM_ICTL            0x100
> +#define UNICAM_ISTA            0x104
> +#define UNICAM_IDI0            0x108
> +#define UNICAM_IPIPE           0x10c
> +#define UNICAM_IBSA0           0x110
> +#define UNICAM_IBEA0           0x114
> +#define UNICAM_IBLS            0x118
> +#define UNICAM_IBWP            0x11c
> +#define UNICAM_IHWIN           0x120
> +#define UNICAM_IHSTA           0x124
> +#define UNICAM_IVWIN           0x128
> +#define UNICAM_IVSTA           0x12c
> +#define UNICAM_ICC             0x130
> +#define UNICAM_ICS             0x134
> +#define UNICAM_IDC             0x138
> +#define UNICAM_IDPO            0x13c
> +#define UNICAM_IDCA            0x140
> +#define UNICAM_IDCD            0x144
> +#define UNICAM_IDS             0x148
> +#define UNICAM_DCS             0x200
> +#define UNICAM_DBSA0           0x204
> +#define UNICAM_DBEA0           0x208
> +#define UNICAM_DBWP            0x20c
> +#define UNICAM_DBCTL           0x300
> +#define UNICAM_IBSA1           0x304
> +#define UNICAM_IBEA1           0x308
> +#define UNICAM_IDI1            0x30c
> +#define UNICAM_DBSA1           0x310
> +#define UNICAM_DBEA1           0x314
> +#define UNICAM_MISC            0x400
> +
> +/*
> + * The following bitmasks are from the kernel released by Broadcom
> + * for Android - https://android.googlesource.com/kernel/bcm/
> + * The Rhea, Hawaii, and Java chips all contain the same VideoCore4
> + * Unicam block as BCM2835, as defined in eg
> + * arch/arm/mach-rhea/include/mach/rdb_A0/brcm_rdb_cam.h and similar.
> + * Values reworked to use the kernel BIT and GENMASK macros.
> + *
> + * Some of the bit mnenomics have been amended to match the datasheet.
> + */
> +/* UNICAM_CTRL Register */
> +#define UNICAM_CPE             BIT(0)
> +#define UNICAM_MEM             BIT(1)
> +#define UNICAM_CPR             BIT(2)
> +#define UNICAM_CPM_MASK                GENMASK(3, 3)
> +#define UNICAM_CPM_CSI2                0
> +#define UNICAM_CPM_CCP2                1
> +#define UNICAM_SOE             BIT(4)
> +#define UNICAM_DCM_MASK                GENMASK(5, 5)
> +#define UNICAM_DCM_STROBE      0
> +#define UNICAM_DCM_DATA                1
> +#define UNICAM_SLS             BIT(6)
> +#define UNICAM_PFT_MASK                GENMASK(11, 8)
> +#define UNICAM_OET_MASK                GENMASK(20, 12)
> +
> +/* UNICAM_STA Register */
> +#define UNICAM_SYN             BIT(0)
> +#define UNICAM_CS              BIT(1)
> +#define UNICAM_SBE             BIT(2)
> +#define UNICAM_PBE             BIT(3)
> +#define UNICAM_HOE             BIT(4)
> +#define UNICAM_PLE             BIT(5)
> +#define UNICAM_SSC             BIT(6)
> +#define UNICAM_CRCE            BIT(7)
> +#define UNICAM_OES             BIT(8)
> +#define UNICAM_IFO             BIT(9)
> +#define UNICAM_OFO             BIT(10)
> +#define UNICAM_BFO             BIT(11)
> +#define UNICAM_DL              BIT(12)
> +#define UNICAM_PS              BIT(13)
> +#define UNICAM_IS              BIT(14)
> +#define UNICAM_PI0             BIT(15)
> +#define UNICAM_PI1             BIT(16)
> +#define UNICAM_FSI_S           BIT(17)
> +#define UNICAM_FEI_S           BIT(18)
> +#define UNICAM_LCI_S           BIT(19)
> +#define UNICAM_BUF0_RDY                BIT(20)
> +#define UNICAM_BUF0_NO         BIT(21)
> +#define UNICAM_BUF1_RDY                BIT(22)
> +#define UNICAM_BUF1_NO         BIT(23)
> +#define UNICAM_DI              BIT(24)
> +
> +#define UNICAM_STA_MASK_ALL \
> +               (UNICAM_DL | \
> +               UNICAM_SBE | \
> +               UNICAM_PBE | \
> +               UNICAM_HOE | \
> +               UNICAM_PLE | \
> +               UNICAM_SSC | \
> +               UNICAM_CRCE | \
> +               UNICAM_IFO | \
> +               UNICAM_OFO | \
> +               UNICAM_PS | \
> +               UNICAM_PI0 | \
> +               UNICAM_PI1)
> +
> +/* UNICAM_ANA Register */
> +#define UNICAM_APD             BIT(0)
> +#define UNICAM_BPD             BIT(1)
> +#define UNICAM_AR              BIT(2)
> +#define UNICAM_DDL             BIT(3)
> +#define UNICAM_CTATADJ_MASK    GENMASK(7, 4)
> +#define UNICAM_PTATADJ_MASK    GENMASK(11, 8)
> +
> +/* UNICAM_PRI Register */
> +#define UNICAM_PE              BIT(0)
> +#define UNICAM_PT_MASK         GENMASK(2, 1)
> +#define UNICAM_NP_MASK         GENMASK(7, 4)
> +#define UNICAM_PP_MASK         GENMASK(11, 8)
> +#define UNICAM_BS_MASK         GENMASK(15, 12)
> +#define UNICAM_BL_MASK         GENMASK(17, 16)
> +
> +/* UNICAM_CLK Register */
> +#define UNICAM_CLE             BIT(0)
> +#define UNICAM_CLPD            BIT(1)
> +#define UNICAM_CLLPE           BIT(2)
> +#define UNICAM_CLHSE           BIT(3)
> +#define UNICAM_CLTRE           BIT(4)
> +#define UNICAM_CLAC_MASK       GENMASK(8, 5)
> +#define UNICAM_CLSTE           BIT(29)
> +
> +/* UNICAM_CLT Register */
> +#define UNICAM_CLT1_MASK       GENMASK(7, 0)
> +#define UNICAM_CLT2_MASK       GENMASK(15, 8)
> +
> +/* UNICAM_DATn Registers */
> +#define UNICAM_DLE             BIT(0)
> +#define UNICAM_DLPD            BIT(1)
> +#define UNICAM_DLLPE           BIT(2)
> +#define UNICAM_DLHSE           BIT(3)
> +#define UNICAM_DLTRE           BIT(4)
> +#define UNICAM_DLSM            BIT(5)
> +#define UNICAM_DLFO            BIT(28)
> +#define UNICAM_DLSTE           BIT(29)
> +
> +#define UNICAM_DAT_MASK_ALL    (UNICAM_DLSTE | UNICAM_DLFO)
> +
> +/* UNICAM_DLT Register */
> +#define UNICAM_DLT1_MASK       GENMASK(7, 0)
> +#define UNICAM_DLT2_MASK       GENMASK(15, 8)
> +#define UNICAM_DLT3_MASK       GENMASK(23, 16)
> +
> +/* UNICAM_ICTL Register */
> +#define UNICAM_FSIE            BIT(0)
> +#define UNICAM_FEIE            BIT(1)
> +#define UNICAM_IBOB            BIT(2)
> +#define UNICAM_FCM             BIT(3)
> +#define UNICAM_TFC             BIT(4)
> +#define UNICAM_LIP_MASK                GENMASK(6, 5)
> +#define UNICAM_LCIE_MASK       GENMASK(28, 16)
> +
> +/* UNICAM_IDI0/1 Register */
> +#define UNICAM_ID0_MASK                GENMASK(7, 0)
> +#define UNICAM_ID1_MASK                GENMASK(15, 8)
> +#define UNICAM_ID2_MASK                GENMASK(23, 16)
> +#define UNICAM_ID3_MASK                GENMASK(31, 24)
> +
> +/* UNICAM_ISTA Register */
> +#define UNICAM_FSI             BIT(0)
> +#define UNICAM_FEI             BIT(1)
> +#define UNICAM_LCI             BIT(2)
> +
> +#define UNICAM_ISTA_MASK_ALL   (UNICAM_FSI | UNICAM_FEI | UNICAM_LCI)
> +
> +/* UNICAM_IPIPE Register */
> +#define UNICAM_PUM_MASK                GENMASK(2, 0)
> +/* Unpacking modes */
> +#define UNICAM_PUM_NONE                0
> +#define UNICAM_PUM_UNPACK6     1
> +#define UNICAM_PUM_UNPACK7     2
> +#define UNICAM_PUM_UNPACK8     3
> +#define UNICAM_PUM_UNPACK10    4
> +#define UNICAM_PUM_UNPACK12    5
> +#define UNICAM_PUM_UNPACK14    6
> +#define UNICAM_PUM_UNPACK16    7
> +#define UNICAM_DDM_MASK                GENMASK(6, 3)
> +#define UNICAM_PPM_MASK                GENMASK(9, 7)
> +/* Packing modes */
> +#define UNICAM_PPM_NONE                0
> +#define UNICAM_PPM_PACK8       1
> +#define UNICAM_PPM_PACK10      2
> +#define UNICAM_PPM_PACK12      3
> +#define UNICAM_PPM_PACK14      4
> +#define UNICAM_PPM_PACK16      5
> +#define UNICAM_DEM_MASK                GENMASK(11, 10)
> +#define UNICAM_DEBL_MASK       GENMASK(14, 12)
> +#define UNICAM_ICM_MASK                GENMASK(16, 15)
> +#define UNICAM_IDM_MASK                GENMASK(17, 17)
> +
> +/* UNICAM_ICC Register */
> +#define UNICAM_ICFL_MASK       GENMASK(4, 0)
> +#define UNICAM_ICFH_MASK       GENMASK(9, 5)
> +#define UNICAM_ICST_MASK       GENMASK(12, 10)
> +#define UNICAM_ICLT_MASK       GENMASK(15, 13)
> +#define UNICAM_ICLL_MASK       GENMASK(31, 16)
> +
> +/* UNICAM_DCS Register */
> +#define UNICAM_DIE             BIT(0)
> +#define UNICAM_DIM             BIT(1)
> +#define UNICAM_DBOB            BIT(3)
> +#define UNICAM_FDE             BIT(4)
> +#define UNICAM_LDP             BIT(5)
> +#define UNICAM_EDL_MASK                GENMASK(15, 8)
> +
> +/* UNICAM_DBCTL Register */
> +#define UNICAM_DBEN            BIT(0)
> +#define UNICAM_BUF0_IE         BIT(1)
> +#define UNICAM_BUF1_IE         BIT(2)
> +
> +/* UNICAM_CMP[0,1] register */
> +#define UNICAM_PCE             BIT(31)
> +#define UNICAM_GI              BIT(9)
> +#define UNICAM_CPH             BIT(8)
> +#define UNICAM_PCVC_MASK       GENMASK(7, 6)
> +#define UNICAM_PCDT_MASK       GENMASK(5, 0)
> +
> +/* UNICAM_MISC register */
> +#define UNICAM_FL0             BIT(6)
> +#define UNICAM_FL1             BIT(9)
> +
> +#endif
> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> new file mode 100644
> index 000000000000..716c89b8a217
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> @@ -0,0 +1,2607 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * BCM283x / BCM271x Unicam Capture Driver
> + *
> + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> + *
> + * Dave Stevenson <[e-mail]>
> + *
> + * Based on TI am437x driver by
> + *   Benoit Parrot <[e-mail]>
> + *   Lad, Prabhakar <[e-mail]>
> + *
> + * and TI CAL camera interface driver by
> + *    Benoit Parrot <[e-mail]>
> + *
> + *
> + * There are two camera drivers in the kernel for BCM283x - this one and
> + * bcm2835-camera (currently in staging).
> + *
> + * This driver directly controls the Unicam peripheral - there is no
> + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> + * and writes it into SDRAM. The only potential processing options are to
> + * repack Bayer data into an alternate format, and applying windowing. The
> + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> + * where the relevant formats are defined, and will automatically configure the
> + * repacking as required. Support for windowing may be added later.
> + *
> + * It should be possible to connect this driver to any sensor with a suitable
> + * output interface and V4L2 subdevice driver.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +#include <linux/videodev2.h>
> +
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-dev.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-mc.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "bcm2835-unicam-regs.h"
> +
> +#define UNICAM_MODULE_NAME             "unicam"
> +
> +/*
> + * Unicam must request a minimum of 250Mhz from the VPU clock.
> + * Otherwise the input FIFOs overrun and cause image corruption.
> + */
> +#define UNICAM_MIN_VPU_CLOCK_RATE      (250 * 1000 * 1000)
> +
> +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> +#define UNICAM_DMA_BPL_ALIGNMENT       16
> +
> +/*
> + * The image stride is stored in a 16 bit register, and needs to be aligned to
> + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> + * constraint on its input, set the image stride alignment to 32 bytes here as
> + * well to avoid incompatible configurations.
> + */
> +#define UNICAM_IMAGE_BPL_ALIGNMENT     32
> +#define UNICAM_IMAGE_MAX_BPL           ((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
> +
> +/*
> + * Max width is therefore determined by the max stride divided by the number of
> + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> + * so adopt a square image for want of anything better.
> + */
> +#define UNICAM_IMAGE_MIN_WIDTH         16
> +#define UNICAM_IMAGE_MIN_HEIGHT                16
> +#define UNICAM_IMAGE_MAX_WIDTH         (UNICAM_IMAGE_MAX_BPL / 4)
> +#define UNICAM_IMAGE_MAX_HEIGHT                UNICAM_IMAGE_MAX_WIDTH
> +
> +/*
> + * There's no intrinsic limits on the width and height for embedded dat. Use
> + * the same maximum values as for the image, to avoid overflows in the image
> + * size computation.
> + */
> +#define UNICAM_META_MIN_WIDTH          1
> +#define UNICAM_META_MIN_HEIGHT         1
> +#define UNICAM_META_MAX_WIDTH          UNICAM_IMAGE_MAX_WIDTH
> +#define UNICAM_META_MAX_HEIGHT         UNICAM_IMAGE_MAX_HEIGHT
> +
> +/*
> + * Size of the dummy buffer. Can be any size really, but the DMA
> + * allocation works in units of page sizes.
> + */
> +#define UNICAM_DUMMY_BUF_SIZE          PAGE_SIZE
> +
> +#define UNICAM_SD_PAD_SINK             0
> +#define UNICAM_SD_PAD_SOURCE_IMAGE     1
> +#define UNICAM_SD_PAD_SOURCE_METADATA  2
> +#define UNICAM_SD_NUM_PADS             (1 + UNICAM_SD_PAD_SOURCE_METADATA)
> +
> +enum unicam_node_type {
> +       UNICAM_IMAGE_NODE,
> +       UNICAM_METADATA_NODE,
> +       UNICAM_MAX_NODES
> +};
> +
> +/*
> + * struct unicam_format_info - Unicam media bus format information
> + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> + * out to 16bpp. 0 if n/a.
> + * @code: V4L2 media bus format code.
> + * @depth: Bits per pixel as delivered from the source.
> + * @csi_dt: CSI data type.
> + * @metadata_fmt: This format only applies to the metadata pad.
> + */
> +struct unicam_format_info {
> +       u32     fourcc;
> +       u32     unpacked_fourcc;
> +       u32     code;
> +       u8      depth;
> +       u8      csi_dt;
> +       bool    metadata_fmt;
> +};
> +
> +struct unicam_buffer {
> +       struct vb2_v4l2_buffer vb;
> +       struct list_head list;
> +       dma_addr_t dma_addr;
> +       unsigned int size;
> +};
> +
> +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> +{
> +       return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> +}
> +
> +struct unicam_node {
> +       bool registered;
> +       bool streaming;
> +       unsigned int id;
> +
> +       /* Pointer to the current v4l2_buffer */
> +       struct unicam_buffer *cur_frm;
> +       /* Pointer to the next v4l2_buffer */
> +       struct unicam_buffer *next_frm;
> +       /* video capture */
> +       const struct unicam_format_info *fmtinfo;
> +       /* Used to store current pixel format */
> +       struct v4l2_format fmt;
> +       /* Buffer queue used in video-buf */
> +       struct vb2_queue buffer_queue;
> +       /* Queue of filled frames */
> +       struct list_head dma_queue;
> +       /* IRQ lock for DMA queue */
> +       spinlock_t dma_queue_lock;
> +       /* lock used to access this structure */
> +       struct mutex lock;
> +       /* Identifies video device for this channel */
> +       struct video_device video_dev;
> +       /* Pointer to the parent handle */
> +       struct unicam_device *dev;
> +       struct media_pad pad;
> +       /*
> +        * Dummy buffer intended to be used by unicam
> +        * if we have no other queued buffers to swap to.
> +        */
> +       struct unicam_buffer dummy_buf;
> +       void *dummy_buf_cpu_addr;
> +};
> +
> +struct unicam_device {
> +       struct kref kref;
> +
> +       /* peripheral base address */
> +       void __iomem *base;
> +       /* clock gating base address */
> +       void __iomem *clk_gate_base;
> +       /* lp clock handle */
> +       struct clk *clock;
> +       /* vpu clock handle */
> +       struct clk *vpu_clock;
> +       /* V4l2 device */
> +       struct v4l2_device v4l2_dev;
> +       struct media_device mdev;
> +
> +       /* parent device */
> +       struct device *dev;
> +       /* subdevice async Notifier */
> +       struct v4l2_async_notifier notifier;
> +       unsigned int sequence;
> +
> +       /* Sensor node */
> +       struct {
> +               struct v4l2_subdev *subdev;
> +               struct media_pad *pad;
> +       } sensor;
> +
> +       /* Internal subdev */
> +       struct {
> +               struct v4l2_subdev sd;
> +               struct media_pad pads[UNICAM_SD_NUM_PADS];
> +               bool streaming;
> +       } subdev;
> +
> +       enum v4l2_mbus_type bus_type;
> +       /*
> +        * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> +        * bus.mipi_csi1.strobe for CCP2.
> +        */
> +       unsigned int bus_flags;
> +       unsigned int max_data_lanes;
> +       unsigned int active_data_lanes;
> +
> +       struct media_pipeline pipe;
> +
> +       struct unicam_node node[UNICAM_MAX_NODES];
> +};
> +
> +static inline struct unicam_device *
> +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> +{
> +       return container_of(notifier, struct unicam_device, notifier);
> +}
> +
> +static inline struct unicam_device *
> +sd_to_unicam_device(struct v4l2_subdev *sd)
> +{
> +       return container_of(sd, struct unicam_device, subdev.sd);
> +}
> +
> +static void unicam_release(struct kref *kref)
> +{
> +       struct unicam_device *unicam =
> +               container_of(kref, struct unicam_device, kref);
> +
> +       if (unicam->mdev.dev)
> +               media_device_cleanup(&unicam->mdev);
> +
> +       kfree(unicam);
> +}
> +
> +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> +{
> +       kref_get(&unicam->kref);
> +       return unicam;
> +}
> +
> +static void unicam_put(struct unicam_device *unicam)
> +{
> +       kref_put(&unicam->kref, unicam_release);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Misc helper functions
> + */
> +
> +static inline bool unicam_sd_pad_is_source(u32 pad)
> +{
> +       /* Camera RX has 1 sink pad, and N source pads */
> +       return pad != UNICAM_SD_PAD_SINK;
> +}
> +
> +static inline bool is_metadata_node(struct unicam_node *node)
> +{
> +       return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> +}
> +
> +static inline bool is_image_node(struct unicam_node *node)
> +{
> +       return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Format data table and helper functions
> + */
> +
> +static const struct v4l2_mbus_framefmt unicam_default_image_format = {
> +       .width = 640,
> +       .height = 480,
> +       .code = MEDIA_BUS_FMT_UYVY8_1X16,
> +       .field = V4L2_FIELD_NONE,
> +       .colorspace = V4L2_COLORSPACE_SRGB,
> +       .ycbcr_enc = V4L2_YCBCR_ENC_601,
> +       .quantization = V4L2_QUANTIZATION_LIM_RANGE,
> +       .xfer_func = V4L2_XFER_FUNC_SRGB,
> +       .flags = 0,
> +};
> +
> +static const struct v4l2_mbus_framefmt unicam_default_meta_format = {
> +       .width = 640,
> +       .height = 2,
> +       .code = MEDIA_BUS_FMT_META_8,
> +       .field = V4L2_FIELD_NONE,
> +};
> +
> +static const struct unicam_format_info unicam_image_formats[] = {
> +       /* YUV Formats */
> +       {
> +               .fourcc         = V4L2_PIX_FMT_YUYV,
> +               .code           = MEDIA_BUS_FMT_YUYV8_1X16,
> +               .depth          = 16,
> +               .csi_dt         = 0x1e,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_UYVY,
> +               .code           = MEDIA_BUS_FMT_UYVY8_1X16,
> +               .depth          = 16,
> +               .csi_dt         = 0x1e,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_YVYU,
> +               .code           = MEDIA_BUS_FMT_YVYU8_1X16,
> +               .depth          = 16,
> +               .csi_dt         = 0x1e,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_VYUY,
> +               .code           = MEDIA_BUS_FMT_VYUY8_1X16,
> +               .depth          = 16,
> +               .csi_dt         = 0x1e,
> +       }, {
> +       /* RGB Formats */
> +               .fourcc         = V4L2_PIX_FMT_RGB565, /* gggbbbbb rrrrrggg */
> +               .code           = MEDIA_BUS_FMT_RGB565_1X16,
> +               .depth          = 16,
> +               .csi_dt         = 0x22,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_RGB24, /* rgb */
> +               .code           = MEDIA_BUS_FMT_RGB888_1X24,
> +               .depth          = 24,
> +               .csi_dt         = 0x24,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_BGR24, /* bgr */
> +               .code           = MEDIA_BUS_FMT_BGR888_1X24,
> +               .depth          = 24,
> +               .csi_dt         = 0x24,
> +       }, {
> +       /* Bayer Formats */
> +               .fourcc         = V4L2_PIX_FMT_SBGGR8,
> +               .code           = MEDIA_BUS_FMT_SBGGR8_1X8,
> +               .depth          = 8,
> +               .csi_dt         = 0x2a,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGBRG8,
> +               .code           = MEDIA_BUS_FMT_SGBRG8_1X8,
> +               .depth          = 8,
> +               .csi_dt         = 0x2a,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGRBG8,
> +               .code           = MEDIA_BUS_FMT_SGRBG8_1X8,
> +               .depth          = 8,
> +               .csi_dt         = 0x2a,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SRGGB8,
> +               .code           = MEDIA_BUS_FMT_SRGGB8_1X8,
> +               .depth          = 8,
> +               .csi_dt         = 0x2a,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SBGGR10P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SBGGR10,
> +               .code           = MEDIA_BUS_FMT_SBGGR10_1X10,
> +               .depth          = 10,
> +               .csi_dt         = 0x2b,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGBRG10P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SGBRG10,
> +               .code           = MEDIA_BUS_FMT_SGBRG10_1X10,
> +               .depth          = 10,
> +               .csi_dt         = 0x2b,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGRBG10P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SGRBG10,
> +               .code           = MEDIA_BUS_FMT_SGRBG10_1X10,
> +               .depth          = 10,
> +               .csi_dt         = 0x2b,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SRGGB10P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SRGGB10,
> +               .code           = MEDIA_BUS_FMT_SRGGB10_1X10,
> +               .depth          = 10,
> +               .csi_dt         = 0x2b,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SBGGR12P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SBGGR12,
> +               .code           = MEDIA_BUS_FMT_SBGGR12_1X12,
> +               .depth          = 12,
> +               .csi_dt         = 0x2c,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGBRG12P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SGBRG12,
> +               .code           = MEDIA_BUS_FMT_SGBRG12_1X12,
> +               .depth          = 12,
> +               .csi_dt         = 0x2c,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGRBG12P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SGRBG12,
> +               .code           = MEDIA_BUS_FMT_SGRBG12_1X12,
> +               .depth          = 12,
> +               .csi_dt         = 0x2c,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SRGGB12P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SRGGB12,
> +               .code           = MEDIA_BUS_FMT_SRGGB12_1X12,
> +               .depth          = 12,
> +               .csi_dt         = 0x2c,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SBGGR14P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SBGGR14,
> +               .code           = MEDIA_BUS_FMT_SBGGR14_1X14,
> +               .depth          = 14,
> +               .csi_dt         = 0x2d,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGBRG14P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SGBRG14,
> +               .code           = MEDIA_BUS_FMT_SGBRG14_1X14,
> +               .depth          = 14,
> +               .csi_dt         = 0x2d,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SGRBG14P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SGRBG14,
> +               .code           = MEDIA_BUS_FMT_SGRBG14_1X14,
> +               .depth          = 14,
> +               .csi_dt         = 0x2d,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_SRGGB14P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_SRGGB14,
> +               .code           = MEDIA_BUS_FMT_SRGGB14_1X14,
> +               .depth          = 14,
> +               .csi_dt         = 0x2d,
> +       }, {
> +       /* 16 bit Bayer formats could be supported. */
> +
> +       /* Greyscale formats */
> +               .fourcc         = V4L2_PIX_FMT_GREY,
> +               .code           = MEDIA_BUS_FMT_Y8_1X8,
> +               .depth          = 8,
> +               .csi_dt         = 0x2a,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_Y10P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_Y10,
> +               .code           = MEDIA_BUS_FMT_Y10_1X10,
> +               .depth          = 10,
> +               .csi_dt         = 0x2b,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_Y12P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_Y12,
> +               .code           = MEDIA_BUS_FMT_Y12_1X12,
> +               .depth          = 12,
> +               .csi_dt         = 0x2c,
> +       }, {
> +               .fourcc         = V4L2_PIX_FMT_Y14P,
> +               .unpacked_fourcc = V4L2_PIX_FMT_Y14,
> +               .code           = MEDIA_BUS_FMT_Y14_1X14,
> +               .depth          = 14,
> +               .csi_dt         = 0x2d,
> +       },
> +};
> +
> +static const struct unicam_format_info unicam_meta_formats[] = {
> +       {
> +               .fourcc         = V4L2_META_FMT_GENERIC_8,
> +               .code           = MEDIA_BUS_FMT_META_8,
> +               .depth          = 8,
> +               .metadata_fmt   = true,
> +       }, {
> +               .fourcc         = V4L2_META_FMT_GENERIC_CSI2_10,
> +               .code           = MEDIA_BUS_FMT_META_10,
> +               .depth          = 10,
> +               .metadata_fmt   = true,
> +       }, {
> +               .fourcc         = V4L2_META_FMT_GENERIC_CSI2_12,
> +               .code           = MEDIA_BUS_FMT_META_12,
> +               .depth          = 12,
> +               .metadata_fmt   = true,
> +       }, {
> +               .fourcc         = V4L2_META_FMT_GENERIC_CSI2_14,
> +               .code           = MEDIA_BUS_FMT_META_14,
> +               .depth          = 14,
> +               .metadata_fmt   = true,
> +       },
> +};
> +
> +/* Format setup functions */
> +static const struct unicam_format_info *
> +unicam_find_format_by_code(u32 code, u32 pad)
> +{
> +       const struct unicam_format_info *formats;
> +       unsigned int num_formats;
> +       unsigned int i;
> +
> +       if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +               formats = unicam_image_formats;
> +               num_formats = ARRAY_SIZE(unicam_image_formats);
> +       } else {
> +               formats = unicam_meta_formats;
> +               num_formats = ARRAY_SIZE(unicam_meta_formats);
> +       }
> +
> +       for (i = 0; i < num_formats; i++) {
> +               if (formats[i].code == code)
> +                       return &formats[i];
> +       }
> +
> +       return NULL;
> +}
> +
> +static const struct unicam_format_info *
> +unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
> +{
> +       const struct unicam_format_info *formats;
> +       unsigned int num_formats;
> +       unsigned int i;
> +
> +       if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +               formats = unicam_image_formats;
> +               num_formats = ARRAY_SIZE(unicam_image_formats);
> +       } else {
> +               formats = unicam_meta_formats;
> +               num_formats = ARRAY_SIZE(unicam_meta_formats);
> +       }
> +
> +       for (i = 0; i < num_formats; ++i) {
> +               if (formats[i].fourcc == fourcc)
> +                       return &formats[i];
> +       }
> +
> +       return NULL;
> +}
> +
> +static void unicam_calc_image_size_bpl(struct unicam_device *unicam,
> +                                      const struct unicam_format_info *fmtinfo,
> +                                      struct v4l2_pix_format *pix)
> +{
> +       u32 min_bpl;
> +
> +       v4l_bound_align_image(&pix->width, UNICAM_IMAGE_MIN_WIDTH,
> +                             UNICAM_IMAGE_MAX_WIDTH, 2,
> +                             &pix->height, UNICAM_IMAGE_MIN_HEIGHT,
> +                             UNICAM_IMAGE_MAX_HEIGHT, 0, 0);
> +
> +       /* Unpacking always goes to 16bpp */
> +       if (pix->pixelformat == fmtinfo->unpacked_fourcc)
> +               min_bpl = pix->width * 2;
> +       else
> +               min_bpl = pix->width * fmtinfo->depth / 8;
> +       min_bpl = ALIGN(min_bpl, UNICAM_IMAGE_BPL_ALIGNMENT);
> +
> +       pix->bytesperline = ALIGN(pix->bytesperline, UNICAM_IMAGE_BPL_ALIGNMENT);
> +       pix->bytesperline = clamp_t(unsigned int, pix->bytesperline, min_bpl,
> +                                   UNICAM_IMAGE_MAX_BPL);
> +
> +       pix->sizeimage = pix->height * pix->bytesperline;
> +}
> +
> +static void unicam_calc_meta_size_bpl(struct unicam_device *unicam,
> +                                     const struct unicam_format_info *fmtinfo,
> +                                     struct v4l2_meta_format *meta)
> +{
> +       v4l_bound_align_image(&meta->width, UNICAM_META_MIN_WIDTH,
> +                             UNICAM_META_MAX_WIDTH, 0,
> +                             &meta->height, UNICAM_META_MIN_HEIGHT,
> +                             UNICAM_META_MAX_HEIGHT, 0, 0);
> +
> +       meta->bytesperline = ALIGN(meta->width * fmtinfo->depth / 8,
> +                                  UNICAM_DMA_BPL_ALIGNMENT);
> +       meta->buffersize = meta->height * meta->bytesperline;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Hardware handling
> + */
> +
> +static inline void unicam_clk_write(struct unicam_device *unicam, u32 val)
> +{
> +       /* Pass the CM_PASSWORD along with the value. */
> +       writel(val | 0x5a000000, unicam->clk_gate_base);
> +}
> +
> +static inline u32 unicam_reg_read(struct unicam_device *unicam, u32 offset)
> +{
> +       return readl(unicam->base + offset);
> +}
> +
> +static inline void unicam_reg_write(struct unicam_device *unicam, u32 offset, u32 val)
> +{
> +       writel(val, unicam->base + offset);
> +}
> +
> +static inline int unicam_get_field(u32 value, u32 mask)
> +{
> +       return (value & mask) >> __ffs(mask);
> +}
> +
> +static inline void unicam_set_field(u32 *valp, u32 field, u32 mask)
> +{
> +       u32 val = *valp;
> +
> +       val &= ~mask;
> +       val |= (field << __ffs(mask)) & mask;
> +       *valp = val;
> +}
> +
> +static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offset,
> +                                         u32 field, u32 mask)
> +{
> +       u32 val = unicam_reg_read(unicam, offset);
> +
> +       unicam_set_field(&val, field, mask);
> +       unicam_reg_write(unicam, offset, val);
> +}
> +
> +static void unicam_wr_dma_addr(struct unicam_node *node,
> +                              struct unicam_buffer *buf)
> +{
> +       dma_addr_t endaddr = buf->dma_addr + buf->size;
> +
> +       if (node->id == UNICAM_IMAGE_NODE) {
> +               unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
> +               unicam_reg_write(node->dev, UNICAM_IBEA0, endaddr);
> +       } else {
> +               unicam_reg_write(node->dev, UNICAM_DBSA0, buf->dma_addr);
> +               unicam_reg_write(node->dev, UNICAM_DBEA0, endaddr);
> +       }
> +}
> +
> +static unsigned int unicam_get_lines_done(struct unicam_device *unicam)
> +{
> +       struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +       unsigned int stride = node->fmt.fmt.pix.bytesperline;
> +       struct unicam_buffer *frm = node->cur_frm;
> +       dma_addr_t cur_addr;
> +
> +       if (!frm)
> +               return 0;
> +
> +       cur_addr = unicam_reg_read(unicam, UNICAM_IBWP);
> +       return (unsigned int)(cur_addr - frm->dma_addr) / stride;
> +}
> +
> +static void unicam_schedule_next_buffer(struct unicam_node *node)
> +{
> +       struct unicam_buffer *buf;
> +
> +       buf = list_first_entry(&node->dma_queue, struct unicam_buffer, list);
> +       node->next_frm = buf;
> +       list_del(&buf->list);
> +
> +       unicam_wr_dma_addr(node, buf);
> +}
> +
> +static void unicam_schedule_dummy_buffer(struct unicam_node *node)
> +{
> +       int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
> +
> +       dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
> +
> +       unicam_wr_dma_addr(node, &node->dummy_buf);
> +
> +       node->next_frm = NULL;
> +}
> +
> +static void unicam_process_buffer_complete(struct unicam_node *node,
> +                                          unsigned int sequence)
> +{
> +       node->cur_frm->vb.field = node->fmt.fmt.pix.field;
> +       node->cur_frm->vb.sequence = sequence;
> +
> +       vb2_buffer_done(&node->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
> +}
> +
> +static void unicam_queue_event_sof(struct unicam_device *unicam)
> +{
> +       struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +
> +       struct v4l2_event event = {
> +               .type = V4L2_EVENT_FRAME_SYNC,
> +               .u.frame_sync.frame_sequence = unicam->sequence,
> +       };
> +
> +       v4l2_event_queue(&node->video_dev, &event);
> +}
> +
> +static irqreturn_t unicam_isr(int irq, void *dev)
> +{
> +       struct unicam_device *unicam = dev;
> +       unsigned int lines_done = unicam_get_lines_done(dev);
> +       unsigned int sequence = unicam->sequence;
> +       unsigned int i;
> +       u32 ista, sta;
> +       bool fe;
> +       u64 ts;
> +
> +       sta = unicam_reg_read(unicam, UNICAM_STA);
> +       /* Write value back to clear the interrupts */
> +       unicam_reg_write(unicam, UNICAM_STA, sta);
> +
> +       ista = unicam_reg_read(unicam, UNICAM_ISTA);
> +       /* Write value back to clear the interrupts */
> +       unicam_reg_write(unicam, UNICAM_ISTA, ista);
> +
> +       dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> +               ista, sta, sequence, lines_done);
> +
> +       if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> +               return IRQ_HANDLED;
> +
> +       /*
> +        * Look for either the Frame End interrupt or the Packet Capture status
> +        * to signal a frame end.
> +        */
> +       fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> +
> +       /*
> +        * We must run the frame end handler first. If we have a valid next_frm
> +        * and we get a simultaneout FE + FS interrupt, running the FS handler
> +        * first would null out the next_frm ptr and we would have lost the
> +        * buffer forever.
> +        */
> +       if (fe) {
> +               /*
> +                * Ensure we have swapped buffers already as we can't
> +                * stop the peripheral. If no buffer is available, use a
> +                * dummy buffer to dump out frames until we get a new buffer
> +                * to use.
> +                */
> +               for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +                       if (!unicam->node[i].streaming)
> +                               continue;
> +
> +                       /*
> +                        * If cur_frm == next_frm, it means we have not had
> +                        * a chance to swap buffers, likely due to having
> +                        * multiple interrupts occurring simultaneously (like FE
> +                        * + FS + LS). In this case, we cannot signal the buffer
> +                        * as complete, as the HW will reuse that buffer.
> +                        */
> +                       if (unicam->node[i].cur_frm &&
> +                           unicam->node[i].cur_frm != unicam->node[i].next_frm)
> +                               unicam_process_buffer_complete(&unicam->node[i],
> +                                                              sequence);
> +                       unicam->node[i].cur_frm = unicam->node[i].next_frm;
> +               }
> +               unicam->sequence++;
> +       }
> +
> +       if (ista & UNICAM_FSI) {
> +               /*
> +                * Timestamp is to be when the first data byte was captured,
> +                * aka frame start.
> +                */
> +               ts = ktime_get_ns();
> +               for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +                       if (!unicam->node[i].streaming)
> +                               continue;
> +
> +                       if (unicam->node[i].cur_frm)
> +                               unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> +                                                               ts;
> +                       else
> +                               dev_dbg(unicam->v4l2_dev.dev,
> +                                       "ISR: [%d] Dropping frame, buffer not available at FS\n",
> +                                       i);
> +                       /*
> +                        * Set the next frame output to go to a dummy frame
> +                        * if we have not managed to obtain another frame
> +                        * from the queue.
> +                        */
> +                       unicam_schedule_dummy_buffer(&unicam->node[i]);
> +               }
> +
> +               unicam_queue_event_sof(unicam);
> +       }
> +
> +       /*
> +        * Cannot swap buffer at frame end, there may be a race condition
> +        * where the HW does not actually swap it if the new frame has
> +        * already started.
> +        */
> +       if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> +               for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +                       if (!unicam->node[i].streaming)
> +                               continue;
> +
> +                       spin_lock(&unicam->node[i].dma_queue_lock);
> +                       if (!list_empty(&unicam->node[i].dma_queue) &&
> +                           !unicam->node[i].next_frm)
> +                               unicam_schedule_next_buffer(&unicam->node[i]);
> +                       spin_unlock(&unicam->node[i].dma_queue_lock);
> +               }
> +       }
> +
> +       if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> +               /* Switch out of trigger mode if selected */
> +               unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> +               unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> +       }
> +       return IRQ_HANDLED;
> +}
> +
> +static void unicam_set_packing_config(struct unicam_device *unicam)
> +{
> +       struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +       u32 pack, unpack;
> +       u32 val;
> +
> +       if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> +               unpack = UNICAM_PUM_NONE;
> +               pack = UNICAM_PPM_NONE;
> +       } else {
> +               switch (node->fmtinfo->depth) {
> +               case 8:
> +                       unpack = UNICAM_PUM_UNPACK8;
> +                       break;
> +               case 10:
> +                       unpack = UNICAM_PUM_UNPACK10;
> +                       break;
> +               case 12:
> +                       unpack = UNICAM_PUM_UNPACK12;
> +                       break;
> +               case 14:
> +                       unpack = UNICAM_PUM_UNPACK14;
> +                       break;
> +               case 16:
> +                       unpack = UNICAM_PUM_UNPACK16;
> +                       break;
> +               default:
> +                       unpack = UNICAM_PUM_NONE;
> +                       break;
> +               }
> +
> +               /* Repacking is always to 16bpp */
> +               pack = UNICAM_PPM_PACK16;
> +       }
> +
> +       val = 0;
> +       unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> +       unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> +       unicam_reg_write(unicam, UNICAM_IPIPE, val);
> +}
> +
> +static void unicam_cfg_image_id(struct unicam_device *unicam)
> +{
> +       struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +
> +       if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +               /* CSI2 mode, hardcode VC 0 for now. */
> +               unicam_reg_write(unicam, UNICAM_IDI0,
> +                                (0 << 6) | node->fmtinfo->csi_dt);
> +       } else {
> +               /* CCP2 mode */
> +               unicam_reg_write(unicam, UNICAM_IDI0,
> +                                0x80 | node->fmtinfo->csi_dt);
> +       }
> +}
> +
> +static void unicam_enable_ed(struct unicam_device *unicam)
> +{
> +       u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> +
> +       unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> +       /* Do not wrap at the end of the embedded data buffer */
> +       unicam_set_field(&val, 0, UNICAM_DBOB);
> +
> +       unicam_reg_write(unicam, UNICAM_DCS, val);
> +}
> +
> +static void unicam_start_rx(struct unicam_device *unicam,
> +                           struct unicam_buffer *buf)
> +{
> +       struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +       int line_int_freq = node->fmt.fmt.pix.height >> 2;
> +       unsigned int i;
> +       u32 val;
> +
> +       if (line_int_freq < 128)
> +               line_int_freq = 128;
> +
> +       /* Enable lane clocks */
> +       val = 1;
> +       for (i = 0; i < unicam->active_data_lanes; i++)
> +               val = val << 2 | 1;
> +       unicam_clk_write(unicam, val);
> +
> +       /* Basic init */
> +       unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> +
> +       /* Enable analogue control, and leave in reset. */
> +       val = UNICAM_AR;
> +       unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> +       unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> +       unicam_reg_write(unicam, UNICAM_ANA, val);
> +       usleep_range(1000, 2000);
> +
> +       /* Come out of reset */
> +       unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> +
> +       /* Peripheral reset */
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> +
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> +
> +       /* Enable Rx control. */
> +       val = unicam_reg_read(unicam, UNICAM_CTRL);
> +       if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +               unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> +               unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> +       } else {
> +               unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> +               unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> +       }
> +       /* Packet framer timeout */
> +       unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> +       unicam_set_field(&val, 128, UNICAM_OET_MASK);
> +       unicam_reg_write(unicam, UNICAM_CTRL, val);
> +
> +       unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> +       unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> +
> +       /* AXI bus access QoS setup */
> +       val = unicam_reg_read(unicam, UNICAM_PRI);
> +       unicam_set_field(&val, 0, UNICAM_BL_MASK);
> +       unicam_set_field(&val, 0, UNICAM_BS_MASK);
> +       unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> +       unicam_set_field(&val, 8, UNICAM_NP_MASK);
> +       unicam_set_field(&val, 2, UNICAM_PT_MASK);
> +       unicam_set_field(&val, 1, UNICAM_PE);
> +       unicam_reg_write(unicam, UNICAM_PRI, val);
> +
> +       unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> +
> +       /* Always start in trigger frame capture mode (UNICAM_FCM set) */
> +       val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> +       unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> +       unicam_reg_write(unicam, UNICAM_ICTL, val);
> +       unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> +       unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> +
> +       /* tclk_term_en */
> +       unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> +       /* tclk_settle */
> +       unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> +       /* td_term_en */
> +       unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> +       /* ths_settle */
> +       unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> +       /* trx_enable */
> +       unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> +
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> +
> +       /* Packet compare setup - required to avoid missing frame ends */
> +       val = 0;
> +       unicam_set_field(&val, 1, UNICAM_PCE);
> +       unicam_set_field(&val, 1, UNICAM_GI);
> +       unicam_set_field(&val, 1, UNICAM_CPH);
> +       unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> +       unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> +       unicam_reg_write(unicam, UNICAM_CMP0, val);
> +
> +       /* Enable clock lane and set up terminations */
> +       val = 0;
> +       if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +               /* CSI2 */
> +               unicam_set_field(&val, 1, UNICAM_CLE);
> +               unicam_set_field(&val, 1, UNICAM_CLLPE);
> +               if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> +                       unicam_set_field(&val, 1, UNICAM_CLTRE);
> +                       unicam_set_field(&val, 1, UNICAM_CLHSE);
> +               }
> +       } else {
> +               /* CCP2 */
> +               unicam_set_field(&val, 1, UNICAM_CLE);
> +               unicam_set_field(&val, 1, UNICAM_CLHSE);
> +               unicam_set_field(&val, 1, UNICAM_CLTRE);
> +       }
> +       unicam_reg_write(unicam, UNICAM_CLK, val);
> +
> +       /*
> +        * Enable required data lanes with appropriate terminations.
> +        * The same value needs to be written to UNICAM_DATn registers for
> +        * the active lanes, and 0 for inactive ones.
> +        */
> +       val = 0;
> +       if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +               /* CSI2 */
> +               unicam_set_field(&val, 1, UNICAM_DLE);
> +               unicam_set_field(&val, 1, UNICAM_DLLPE);
> +               if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> +                       unicam_set_field(&val, 1, UNICAM_DLTRE);
> +                       unicam_set_field(&val, 1, UNICAM_DLHSE);
> +               }
> +       } else {
> +               /* CCP2 */
> +               unicam_set_field(&val, 1, UNICAM_DLE);
> +               unicam_set_field(&val, 1, UNICAM_DLHSE);
> +               unicam_set_field(&val, 1, UNICAM_DLTRE);
> +       }
> +       unicam_reg_write(unicam, UNICAM_DAT0, val);
> +
> +       if (unicam->active_data_lanes == 1)
> +               val = 0;
> +       unicam_reg_write(unicam, UNICAM_DAT1, val);
> +
> +       if (unicam->max_data_lanes > 2) {
> +               /*
> +                * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> +                * instance supports more than 2 data lanes.
> +                */
> +               if (unicam->active_data_lanes == 2)
> +                       val = 0;
> +               unicam_reg_write(unicam, UNICAM_DAT2, val);
> +
> +               if (unicam->active_data_lanes == 3)
> +                       val = 0;
> +               unicam_reg_write(unicam, UNICAM_DAT3, val);
> +       }
> +
> +       unicam_reg_write(unicam, UNICAM_IBLS,
> +                        node->fmt.fmt.pix.bytesperline);
> +       unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> +       unicam_set_packing_config(unicam);
> +       unicam_cfg_image_id(unicam);
> +
> +       val = unicam_reg_read(unicam, UNICAM_MISC);
> +       unicam_set_field(&val, 1, UNICAM_FL0);
> +       unicam_set_field(&val, 1, UNICAM_FL1);
> +       unicam_reg_write(unicam, UNICAM_MISC, val);
> +
> +       /* Enable peripheral */
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> +
> +       /* Load image pointers */
> +       unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> +
> +       /*
> +        * Enable trigger only for the first frame to
> +        * sync correctly to the FS from the source.
> +        */
> +       unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> +}
> +
> +static void unicam_start_metadata(struct unicam_device *unicam,
> +                                 struct unicam_buffer *buf)
> +{
> +       struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
> +
> +       unicam_enable_ed(unicam);
> +       unicam_wr_dma_addr(node, buf);
> +       unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
> +}
> +
> +static void unicam_disable(struct unicam_device *unicam)
> +{
> +       /* Analogue lane control disable */
> +       unicam_reg_write_field(unicam, UNICAM_ANA, 1, UNICAM_DDL);
> +
> +       /* Stop the output engine */
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_SOE);
> +
> +       /* Disable the data lanes. */
> +       unicam_reg_write(unicam, UNICAM_DAT0, 0);
> +       unicam_reg_write(unicam, UNICAM_DAT1, 0);
> +
> +       if (unicam->max_data_lanes > 2) {
> +               unicam_reg_write(unicam, UNICAM_DAT2, 0);
> +               unicam_reg_write(unicam, UNICAM_DAT3, 0);
> +       }
> +
> +       /* Peripheral reset */
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> +       usleep_range(50, 100);
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> +
> +       /* Disable peripheral */
> +       unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> +
> +       /* Clear ED setup */
> +       unicam_reg_write(unicam, UNICAM_DCS, 0);
> +
> +       /* Disable all lane clocks */
> +       unicam_clk_write(unicam, 0);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * V4L2 subdev operations
> + */
> +
> +static int __unicam_subdev_set_routing(struct v4l2_subdev *sd,
> +                                      struct v4l2_subdev_state *state,
> +                                      struct v4l2_subdev_krouting *routing)
> +{
> +       struct v4l2_subdev_route *route;
> +       int ret;
> +
> +       ret = v4l2_subdev_routing_validate(sd, routing,
> +                                          V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
> +       if (ret)
> +               return ret;
> +
> +       ret = v4l2_subdev_set_routing(sd, state, routing);
> +       if (ret)
> +               return ret;
> +
> +       for_each_active_route(&state->routing, route) {
> +               const struct v4l2_mbus_framefmt *def_fmt;
> +               struct v4l2_mbus_framefmt *fmt;
> +
> +               if (route->source_pad == UNICAM_SD_PAD_SOURCE_IMAGE)
> +                       def_fmt = &unicam_default_image_format;
> +               else
> +                       def_fmt = &unicam_default_meta_format;
> +
> +               fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
> +                                                  route->sink_stream);
> +               *fmt = *def_fmt;
> +               fmt = v4l2_subdev_state_get_format(state, route->source_pad,
> +                                                  route->source_stream);
> +               *fmt = *def_fmt;
> +       }
> +
> +       return 0;
> +}
> +
> +static int unicam_subdev_init_state(struct v4l2_subdev *sd,
> +                                   struct v4l2_subdev_state *state)
> +{
> +       struct v4l2_subdev_route routes[] = {
> +               {
> +                       .sink_pad = UNICAM_SD_PAD_SINK,
> +                       .sink_stream = 0,
> +                       .source_pad = UNICAM_SD_PAD_SOURCE_IMAGE,
> +                       .source_stream = 0,
> +                       .flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
> +               },
> +       };
> +
> +       struct v4l2_subdev_krouting routing = {
> +               .len_routes = ARRAY_SIZE(routes),
> +               .num_routes = ARRAY_SIZE(routes),
> +               .routes = routes,
> +       };
> +
> +       /* Initialize routing to single route to the fist source pad. */
> +       return __unicam_subdev_set_routing(sd, state, &routing);
> +}
> +
> +static int unicam_subdev_enum_mbus_code(struct v4l2_subdev *sd,
> +                                       struct v4l2_subdev_state *state,
> +                                       struct v4l2_subdev_mbus_code_enum *code)
> +{
> +       u32 pad, stream;
> +       int ret;
> +
> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +                                                   code->pad, code->stream,
> +                                                   &pad, &stream);
> +       if (ret)
> +               return ret;
> +
> +       if (unicam_sd_pad_is_source(code->pad)) {
> +               /* No transcoding, source and sink codes must match. */
> +               const struct v4l2_mbus_framefmt *fmt;
> +
> +               fmt = v4l2_subdev_state_get_format(state, pad, stream);
> +               if (!fmt)
> +                       return -EINVAL;
> +
> +               if (code->index > 0)
> +                       return -EINVAL;
> +
> +               code->code = fmt->code;
> +       } else {
> +               const struct unicam_format_info *formats;
> +               unsigned int num_formats;
> +
> +               if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +                       formats = unicam_image_formats;
> +                       num_formats = ARRAY_SIZE(unicam_image_formats);
> +               } else {
> +                       formats = unicam_meta_formats;
> +                       num_formats = ARRAY_SIZE(unicam_meta_formats);
> +               }
> +
> +               if (code->index >= num_formats)
> +                       return -EINVAL;
> +
> +               code->code = formats[code->index].code;
> +       }
> +
> +       return 0;
> +}
> +
> +static int unicam_subdev_enum_frame_size(struct v4l2_subdev *sd,
> +                                        struct v4l2_subdev_state *state,
> +                                        struct v4l2_subdev_frame_size_enum *fse)
> +{
> +       u32 pad, stream;
> +       int ret;
> +
> +       if (fse->index > 0)
> +               return -EINVAL;
> +
> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing, fse->pad,
> +                                                   fse->stream, &pad,
> +                                                   &stream);
> +       if (ret)
> +               return ret;
> +
> +       if (unicam_sd_pad_is_source(fse->pad)) {
> +               /* No transcoding, source and sink formats must match. */
> +               const struct v4l2_mbus_framefmt *fmt;
> +
> +               fmt = v4l2_subdev_state_get_format(state, pad, stream);
> +               if (!fmt)
> +                       return -EINVAL;
> +
> +               if (fse->code != fmt->code)
> +                       return -EINVAL;
> +
> +               fse->min_width = fmt->width;
> +               fse->max_width = fmt->width;
> +               fse->min_height = fmt->height;
> +               fse->max_height = fmt->height;
> +       } else {
> +               const struct unicam_format_info *fmtinfo;
> +
> +               fmtinfo = unicam_find_format_by_code(fse->code, pad);
> +               if (!fmtinfo)
> +                       return -EINVAL;
> +
> +               if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +                       fse->min_width = UNICAM_IMAGE_MIN_WIDTH;
> +                       fse->max_width = UNICAM_IMAGE_MAX_WIDTH;
> +                       fse->min_height = UNICAM_IMAGE_MIN_HEIGHT;
> +                       fse->max_height = UNICAM_IMAGE_MAX_HEIGHT;
> +               } else {
> +                       fse->min_width = UNICAM_META_MIN_WIDTH;
> +                       fse->max_width = UNICAM_META_MAX_WIDTH;
> +                       fse->min_height = UNICAM_META_MIN_HEIGHT;
> +                       fse->max_height = UNICAM_META_MAX_HEIGHT;
> +               }
> +       }
> +
> +       return 0;
> +}
> +
> +static int unicam_subdev_set_format(struct v4l2_subdev *sd,
> +                                   struct v4l2_subdev_state *state,
> +                                   struct v4l2_subdev_format *format)
> +{
> +       struct unicam_device *unicam = sd_to_unicam_device(sd);
> +       struct v4l2_mbus_framefmt *sink_format, *source_format;
> +       const struct unicam_format_info *fmtinfo;
> +       u32 source_pad, source_stream;
> +       int ret;
> +
> +       if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
> +           unicam->subdev.streaming)
> +               return -EBUSY;
> +
> +       /* No transcoding, source and sink formats must match. */
> +       if (unicam_sd_pad_is_source(format->pad))
> +               return v4l2_subdev_get_fmt(sd, state, format);
> +
> +       /*
> +        * Allowed formats for the stream on the sink pad depend on what source
> +        * pad the stream is routed to. Find the corresponding source pad and
> +        * use it to validate the media bus code.
> +        */
> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +                                                   format->pad, format->stream,
> +                                                   &source_pad, &source_stream);
> +       if (ret)
> +               return ret;
> +
> +       fmtinfo = unicam_find_format_by_code(format->format.code, source_pad);
> +       if (!fmtinfo) {
> +               fmtinfo = source_pad == UNICAM_SD_PAD_SOURCE_IMAGE
> +                       ? &unicam_image_formats[0] : &unicam_meta_formats[0];
> +               format->format.code = fmtinfo->code;
> +       }
> +
> +       if (source_pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +               format->format.width = clamp_t(unsigned int,
> +                                              format->format.width,
> +                                              UNICAM_IMAGE_MIN_WIDTH,
> +                                              UNICAM_IMAGE_MAX_WIDTH);
> +               format->format.height = clamp_t(unsigned int,
> +                                               format->format.height,
> +                                               UNICAM_IMAGE_MIN_HEIGHT,
> +                                               UNICAM_IMAGE_MAX_HEIGHT);
> +               format->format.field = V4L2_FIELD_NONE;
> +       } else {
> +               format->format.width = clamp_t(unsigned int,
> +                                              format->format.width,
> +                                              UNICAM_META_MIN_WIDTH,
> +                                              UNICAM_META_MAX_WIDTH);
> +               format->format.height = clamp_t(unsigned int,
> +                                               format->format.height,
> +                                               UNICAM_META_MIN_HEIGHT,
> +                                               UNICAM_META_MAX_HEIGHT);
> +               format->format.field = V4L2_FIELD_NONE;
> +
> +               /* Colorspace don't apply to metadata. */
> +               format->format.colorspace = 0;
> +               format->format.ycbcr_enc = 0;
> +               format->format.quantization = 0;
> +               format->format.xfer_func = 0;
> +       }
> +
> +       sink_format = v4l2_subdev_state_get_format(state, format->pad,
> +                                                  format->stream);
> +       source_format = v4l2_subdev_state_get_format(state, source_pad,
> +                                                    source_stream);
> +       *sink_format = format->format;
> +       *source_format = format->format;
> +
> +       return 0;
> +}
> +
> +static int unicam_subdev_set_routing(struct v4l2_subdev *sd,
> +                                    struct v4l2_subdev_state *state,
> +                                    enum v4l2_subdev_format_whence which,
> +                                    struct v4l2_subdev_krouting *routing)
> +{
> +       struct unicam_device *unicam = sd_to_unicam_device(sd);
> +
> +       if (which == V4L2_SUBDEV_FORMAT_ACTIVE && unicam->subdev.streaming)
> +               return -EBUSY;
> +
> +       return __unicam_subdev_set_routing(sd, state, routing);
> +}
> +
> +static int unicam_sd_enable_streams(struct v4l2_subdev *sd,
> +                                   struct v4l2_subdev_state *state, u32 pad,
> +                                   u64 streams_mask)
> +{
> +       struct unicam_device *unicam = sd_to_unicam_device(sd);
> +       u32 other_pad, other_stream;
> +       int ret;
> +
> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> +                                                   &other_pad, &other_stream);
> +       if (ret)
> +               return ret;
> +
> +       unicam->sequence = 0;
> +
> +       ret = v4l2_subdev_enable_streams(unicam->sensor.subdev,
> +                                        unicam->sensor.pad->index,
> +                                        BIT(other_stream));
> +       if (ret) {
> +               dev_err(unicam->dev, "stream on failed in subdev\n");
> +               return ret;
> +       }
> +
> +       unicam->subdev.streaming = true;
> +
> +       return 0;
> +}
> +
> +static int unicam_sd_disable_streams(struct v4l2_subdev *sd,
> +                                    struct v4l2_subdev_state *state, u32 pad,
> +                                    u64 streams_mask)
> +{
> +       struct unicam_device *unicam = sd_to_unicam_device(sd);
> +       u32 other_pad, other_stream;
> +       int ret;
> +
> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> +                                                   &other_pad, &other_stream);
> +       if (ret)
> +               return ret;
> +
> +       v4l2_subdev_disable_streams(unicam->sensor.subdev,
> +                                   unicam->sensor.pad->index,
> +                                   BIT(other_stream));
> +
> +       unicam->subdev.streaming = false;
> +
> +       return 0;
> +}
> +
> +static const struct v4l2_subdev_pad_ops unicam_subdev_pad_ops = {
> +       .enum_mbus_code         = unicam_subdev_enum_mbus_code,
> +       .enum_frame_size        = unicam_subdev_enum_frame_size,
> +       .get_fmt                = v4l2_subdev_get_fmt,
> +       .set_fmt                = unicam_subdev_set_format,
> +       .set_routing            = unicam_subdev_set_routing,
> +       .enable_streams         = unicam_sd_enable_streams,
> +       .disable_streams        = unicam_sd_disable_streams,
> +};
> +
> +static const struct v4l2_subdev_ops unicam_subdev_ops = {
> +       .pad                    = &unicam_subdev_pad_ops,
> +};
> +
> +static const struct v4l2_subdev_internal_ops unicam_subdev_internal_ops = {
> +       .init_state             = unicam_subdev_init_state,
> +};
> +
> +static const struct media_entity_operations unicam_subdev_media_ops = {
> +       .link_validate          = v4l2_subdev_link_validate,
> +       .has_pad_interdep       = v4l2_subdev_has_pad_interdep,
> +};
> +
> +static int unicam_subdev_init(struct unicam_device *unicam)
> +{
> +       struct v4l2_subdev *sd = &unicam->subdev.sd;
> +       int ret;
> +
> +       v4l2_subdev_init(sd, &unicam_subdev_ops);
> +       sd->internal_ops = &unicam_subdev_internal_ops;
> +       v4l2_set_subdevdata(sd, unicam);
> +
> +       sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> +       sd->entity.ops = &unicam_subdev_media_ops;
> +       sd->dev = unicam->dev;
> +       sd->owner = THIS_MODULE;
> +       sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
> +
> +       strscpy(sd->name, "unicam", sizeof(sd->name));
> +
> +       unicam->subdev.pads[UNICAM_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> +       unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_IMAGE].flags = MEDIA_PAD_FL_SOURCE;
> +       unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_METADATA].flags = MEDIA_PAD_FL_SOURCE;
> +
> +       ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(unicam->subdev.pads),
> +                                    unicam->subdev.pads);
> +       if (ret) {
> +               dev_err(unicam->dev, "Failed to initialize media entity: %d\n",
> +                       ret);
> +               return ret;
> +       }
> +
> +       ret = v4l2_subdev_init_finalize(sd);
> +       if (ret) {
> +               dev_err(unicam->dev, "Failed to initialize subdev: %d\n", ret);
> +               goto err_entity;
> +       }
> +
> +       ret = v4l2_device_register_subdev(&unicam->v4l2_dev, sd);
> +       if (ret) {
> +               dev_err(unicam->dev, "Failed to register subdev: %d\n", ret);
> +               goto err_subdev;
> +       }
> +
> +       return 0;
> +
> +err_subdev:
> +       v4l2_subdev_cleanup(sd);
> +err_entity:
> +       media_entity_cleanup(&sd->entity);
> +       return ret;
> +}
> +
> +static void unicam_subdev_cleanup(struct unicam_device *unicam)
> +{
> +       v4l2_subdev_cleanup(&unicam->subdev.sd);
> +       media_entity_cleanup(&unicam->subdev.sd.entity);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Videobuf2 queue operations
> + */
> +
> +static int unicam_queue_setup(struct vb2_queue *vq,
> +                             unsigned int *nbuffers,
> +                             unsigned int *nplanes,
> +                             unsigned int sizes[],
> +                             struct device *alloc_devs[])
> +{
> +       struct unicam_node *node = vb2_get_drv_priv(vq);
> +       u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> +                : node->fmt.fmt.meta.buffersize;
> +
> +       if (vq->num_buffers + *nbuffers < 3)
> +               *nbuffers = 3 - vq->num_buffers;
> +
> +       if (*nplanes) {
> +               if (sizes[0] < size) {
> +                       dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> +                               sizes[0], size);
> +                       return -EINVAL;
> +               }
> +               size = sizes[0];
> +       }
> +
> +       *nplanes = 1;
> +       sizes[0] = size;
> +
> +       return 0;
> +}hgjk
> +
> +static int unicam_buffer_prepare(struct vb2_buffer *vb)


> +{
> +       struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> +       struct unicam_buffer *buf = to_unicam_buffer(vb);
> +       u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> +                : node->fmt.fmt.meta.buffersize;
> +
> +       if (vb2_plane_size(vb, 0) < size) {
> +               dev_dbg(node->dev->dev,
> +                       "data will not fit into plane (%lu < %u)\n",
> +                       vb2_plane_size(vb, 0), size);
> +               return -EINVAL;
> +       }
> +
> +       buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> +       buf->size = size;
> +
> +       vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> +
> +       return 0;
> +}
> +
> +static void unicam_return_buffers(struct unicam_node *node,
> +                                 enum vb2_buffer_state state)
> +{
> +       struct unicam_buffer *buf, *tmp;
> +
> +       list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> +               list_del(&buf->list);
> +               vb2_buffer_done(&buf->vb.vb2_buf, state);
> +       }
> +
> +       if (node->cur_frm)
> +               vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> +                               state);
> +       if (node->next_frm && node->cur_frm != node->next_frm)
> +               vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> +                               state);
> +
> +       node->cur_frm = NULL;
> +       node->next_frm = NULL;
> +}
> +
> +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> +{
> +       struct unicam_node *node = vb2_get_drv_priv(vq);
> +       struct unicam_device *unicam = node->dev;
> +       struct v4l2_subdev_state *state;
> +       struct unicam_buffer *buf;
> +       unsigned long flags;
> +       int ret;
> +       u32 pad, stream;
> +       u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +                                            : UNICAM_SD_PAD_SOURCE_METADATA;
> +
> +       /* Look for the route for the given pad and stream. */
> +       state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +                                                   remote_pad, 0,
> +                                                   &pad, &stream);
> +       v4l2_subdev_unlock_state(state);
> +
> +       if (ret)
> +               goto err_return_buffers;
> +
> +       dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> +               unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> +               is_metadata_node(node) ? "metadata" : "image");
> +
> +       /* The metadata node can't be started alone. */
> +       if (is_metadata_node(node)) {
> +               if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> +                       dev_err(unicam->dev,
> +                               "Can't start metadata without image\n");
> +                       ret = -EINVAL;
> +                       goto err_return_buffers;
> +               }

There's a slight change of behaviour in this function when compared to
the downstream/BSP non-streams enabled driver.

In the BSP driver, if the embedded data node has been enabled, we wait
for both image and embedded data nodes to have start_streaming()
called before starting the sensor (see
https://github.com/raspberrypi/linux/blob/c04af98514c26014a4f29ec87b3ece95626059bd/drivers/media/platform/bcm2835/bcm2835-unicam.c#L2559).
This is also the same for the Pi 5 CFE driver.

With the logic in this function, we only wait for start_streaming() on
the image node then start the sensor streaming immediately.  When
start_streaming() for the embedded data node is subsequently called,
we end up with the first N buffers missing and/or invalid as the HW
channel is enabled while the sensor is streaming.  I noticed this when
using libcamera where we start image then embedded node.  If I flip
things around (start embedded first then image), everything works as
expected.

Could we add back the test to ensure all nodes are streaming before
starting the sensor?

Regards,
Naush

> +
> +               spin_lock_irqsave(&node->dma_queue_lock, flags);
> +               buf = list_first_entry(&node->dma_queue,
> +                                      struct unicam_buffer, list);
> +               dev_dbg(unicam->dev, "buffer %p\n", buf);
> +               node->cur_frm = buf;
> +               node->next_frm = buf;
> +               list_del(&buf->list);
> +               spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> +
> +               unicam_start_metadata(unicam, buf);
> +               node->streaming = true;
> +               return 0;
> +       }
> +
> +       ret = pm_runtime_resume_and_get(unicam->dev);
> +       if (ret < 0) {
> +               dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> +               goto err_return_buffers;
> +       }
> +
> +       ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> +       if (ret < 0) {
> +               dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> +               goto err_pm_put;
> +       }
> +
> +       spin_lock_irqsave(&node->dma_queue_lock, flags);
> +       buf = list_first_entry(&node->dma_queue,
> +                              struct unicam_buffer, list);
> +       dev_dbg(unicam->dev, "buffer %p\n", buf);
> +       node->cur_frm = buf;
> +       node->next_frm = buf;
> +       list_del(&buf->list);
> +       spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> +
> +       unicam_start_rx(unicam, buf);
> +
> +       ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> +       if (ret < 0) {
> +               dev_err(unicam->dev, "stream on failed in subdev\n");
> +               goto error_pipeline;
> +       }
> +
> +       node->streaming = true;
> +
> +       return 0;
> +
> +error_pipeline:
> +       video_device_pipeline_stop(&node->video_dev);
> +err_pm_put:
> +       pm_runtime_put_sync(unicam->dev);
> +err_return_buffers:
> +       unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> +       return ret;
> +}
> +
> +static void unicam_stop_streaming(struct vb2_queue *vq)
> +{
> +       struct unicam_node *node = vb2_get_drv_priv(vq);
> +       struct unicam_device *unicam = node->dev;
> +       u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +                                                  : UNICAM_SD_PAD_SOURCE_METADATA;
> +
> +       node->streaming = false;
> +
> +       v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> +                                   BIT(0));
> +
> +       /* We can stream only with the image node. */
> +       if (is_metadata_node(node)) {
> +               /*
> +                * Allow the hardware to spin in the dummy buffer.
> +                * This is only really needed if the embedded data pad is
> +                * disabled before the image pad.
> +                */
> +               unicam_wr_dma_addr(node, &node->dummy_buf);
> +               goto dequeue_buffers;
> +       }
> +
> +       unicam_disable(unicam);
> +
> +       video_device_pipeline_stop(&node->video_dev);
> +       pm_runtime_put(unicam->dev);
> +
> +dequeue_buffers:
> +       /* Clear all queued buffers for the node */
> +       unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> +}
> +
> +static void unicam_buffer_queue(struct vb2_buffer *vb)
> +{
> +       struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> +       struct unicam_buffer *buf = to_unicam_buffer(vb);
> +
> +       spin_lock_irq(&node->dma_queue_lock);
> +       list_add_tail(&buf->list, &node->dma_queue);
> +       spin_unlock_irq(&node->dma_queue_lock);
> +}
> +
> +static const struct vb2_ops unicam_video_qops = {
> +       .queue_setup            = unicam_queue_setup,
> +       .wait_prepare           = vb2_ops_wait_prepare,
> +       .wait_finish            = vb2_ops_wait_finish,
> +       .buf_prepare            = unicam_buffer_prepare,
> +       .start_streaming        = unicam_start_streaming,
> +       .stop_streaming         = unicam_stop_streaming,
> +       .buf_queue              = unicam_buffer_queue,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + *  V4L2 video device operations
> + */
> +
> +static int unicam_querycap(struct file *file, void *priv,
> +                          struct v4l2_capability *cap)
> +{
> +       strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> +       strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> +
> +       cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> +
> +       return 0;
> +}
> +
> +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> +                              struct v4l2_fmtdesc *f)
> +{
> +       unsigned int index;
> +       unsigned int i;
> +
> +       for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> +               if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> +                       continue;
> +
> +               if (index == f->index) {
> +                       f->pixelformat = unicam_image_formats[i].fourcc;
> +                       return 0;
> +               }
> +
> +               index++;
> +
> +               if (!unicam_image_formats[i].unpacked_fourcc)
> +                       continue;
> +
> +               if (index == f->index) {
> +                       f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> +                       return 0;
> +               }
> +
> +               index++;
> +       }
> +
> +       return -EINVAL;
> +}
> +
> +static int unicam_g_fmt_vid(struct file *file, void *priv,
> +                           struct v4l2_format *f)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +
> +       *f = node->fmt;
> +
> +       return 0;
> +}
> +
> +static const struct unicam_format_info *
> +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> +{
> +       const struct unicam_format_info *fmtinfo;
> +
> +       /*
> +        * Default to the first format if the requested pixel format code isn't
> +        * supported.
> +        */
> +       fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> +                                              UNICAM_SD_PAD_SOURCE_IMAGE);
> +       if (!fmtinfo) {
> +               fmtinfo = &unicam_image_formats[0];
> +               pix->pixelformat = fmtinfo->fourcc;
> +       }
> +
> +       unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> +
> +       if (pix->field == V4L2_FIELD_ANY)
> +               pix->field = V4L2_FIELD_NONE;
> +
> +       return fmtinfo;
> +}
> +
> +static int unicam_try_fmt_vid(struct file *file, void *priv,
> +                             struct v4l2_format *f)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +
> +       __unicam_try_fmt_vid(node, &f->fmt.pix);
> +       return 0;
> +}
> +
> +static int unicam_s_fmt_vid(struct file *file, void *priv,
> +                           struct v4l2_format *f)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +
> +       if (vb2_is_busy(&node->buffer_queue))
> +               return -EBUSY;
> +
> +       node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> +       node->fmt = *f;
> +
> +       return 0;
> +}
> +
> +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> +                               struct v4l2_fmtdesc *f)
> +{
> +       unsigned int i, index;
> +
> +       for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> +               if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
> +                       continue;
> +               if (!unicam_meta_formats[i].metadata_fmt)
> +                       continue;
> +
> +               if (index == f->index) {
> +                       f->pixelformat = unicam_meta_formats[i].fourcc;
> +                       f->type = V4L2_BUF_TYPE_META_CAPTURE;
> +                       return 0;
> +               }
> +               index++;
> +       }
> +
> +       return -EINVAL;
> +}
> +
> +static int unicam_g_fmt_meta(struct file *file, void *priv,
> +                            struct v4l2_format *f)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +
> +       f->fmt.meta = node->fmt.fmt.meta;
> +
> +       return 0;
> +}
> +
> +static const struct unicam_format_info *
> +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> +{
> +       const struct unicam_format_info *fmtinfo;
> +
> +       /*
> +        * Default to the first format if the requested pixel format code isn't
> +        * supported.
> +        */
> +       fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> +                                              UNICAM_SD_PAD_SOURCE_METADATA);
> +       if (!fmtinfo) {
> +               fmtinfo = &unicam_meta_formats[0];
> +               meta->dataformat = fmtinfo->fourcc;
> +       }
> +
> +       unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> +
> +       return fmtinfo;
> +}
> +
> +static int unicam_try_fmt_meta(struct file *file, void *priv,
> +                              struct v4l2_format *f)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +
> +       __unicam_try_fmt_vid(node, &f->fmt.pix);
> +       return 0;
> +}
> +
> +static int unicam_s_fmt_meta(struct file *file, void *priv,
> +                            struct v4l2_format *f)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +
> +       if (vb2_is_busy(&node->buffer_queue))
> +               return -EBUSY;
> +
> +       node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> +       node->fmt = *f;
> +
> +       return 0;
> +}
> +
> +static int unicam_enum_framesizes(struct file *file, void *fh,
> +                                 struct v4l2_frmsizeenum *fsize)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +       int ret = -EINVAL;
> +
> +       if (fsize->index > 0)
> +               return ret;
> +
> +       if (is_image_node(node)) {
> +               if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> +                                                 UNICAM_SD_PAD_SOURCE_IMAGE))
> +                       return ret;
> +
> +               fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> +               fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> +               fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> +               fsize->stepwise.step_width = 1;
> +               fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> +               fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> +               fsize->stepwise.step_height = 1;
> +       } else {
> +               if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> +                                                 UNICAM_SD_PAD_SOURCE_METADATA))
> +                       return ret;
> +
> +               fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> +               fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> +               fsize->stepwise.step_width = 1;
> +               fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> +               fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> +               fsize->stepwise.step_height = 1;
> +       }
> +
> +       return 0;
> +}
> +
> +static int unicam_log_status(struct file *file, void *fh)
> +{
> +       struct unicam_node *node = video_drvdata(file);
> +       struct unicam_device *unicam = node->dev;
> +       u32 reg;
> +
> +       /* status for sub devices */
> +       v4l2_device_call_all(&unicam->v4l2_dev, 0, core, log_status);
> +
> +       dev_info(unicam->dev, "-----Receiver status-----\n");
> +       dev_info(unicam->dev, "V4L2 width/height:   %ux%u\n",
> +                node->fmt.fmt.pix.width, node->fmt.fmt.pix.height);
> +       dev_info(unicam->dev, "Mediabus format:     %08x\n",
> +                node->fmtinfo->code);
> +       dev_info(unicam->dev, "V4L2 format:         %08x\n",
> +                node->fmt.fmt.pix.pixelformat);
> +       reg = unicam_reg_read(unicam, UNICAM_IPIPE);
> +       dev_info(unicam->dev, "Unpacking/packing:   %u / %u\n",
> +                unicam_get_field(reg, UNICAM_PUM_MASK),
> +                unicam_get_field(reg, UNICAM_PPM_MASK));
> +       dev_info(unicam->dev, "----Live data----\n");
> +       dev_info(unicam->dev, "Programmed stride:   %4u\n",
> +                unicam_reg_read(unicam, UNICAM_IBLS));
> +       dev_info(unicam->dev, "Detected resolution: %ux%u\n",
> +                unicam_reg_read(unicam, UNICAM_IHSTA),
> +                unicam_reg_read(unicam, UNICAM_IVSTA));
> +       dev_info(unicam->dev, "Write pointer:       %08x\n",
> +                unicam_reg_read(unicam, UNICAM_IBWP));
> +
> +       return 0;
> +}
> +
> +static int unicam_subscribe_event(struct v4l2_fh *fh,
> +                                 const struct v4l2_event_subscription *sub)
> +{
> +       switch (sub->type) {
> +       case V4L2_EVENT_FRAME_SYNC:
> +               return v4l2_event_subscribe(fh, sub, 2, NULL);
> +       default:
> +               return -EINVAL;
> +       }
> +}
> +
> +static const struct v4l2_ioctl_ops unicam_ioctl_ops = {
> +       .vidioc_querycap                = unicam_querycap,
> +
> +       .vidioc_enum_fmt_vid_cap        = unicam_enum_fmt_vid,
> +       .vidioc_g_fmt_vid_cap           = unicam_g_fmt_vid,
> +       .vidioc_try_fmt_vid_cap         = unicam_try_fmt_vid,
> +       .vidioc_s_fmt_vid_cap           = unicam_s_fmt_vid,
> +
> +       .vidioc_enum_fmt_meta_cap       = unicam_enum_fmt_meta,
> +       .vidioc_g_fmt_meta_cap          = unicam_g_fmt_meta,
> +       .vidioc_try_fmt_meta_cap        = unicam_try_fmt_meta,
> +       .vidioc_s_fmt_meta_cap          = unicam_s_fmt_meta,
> +
> +       .vidioc_enum_framesizes         = unicam_enum_framesizes,
> +
> +       .vidioc_reqbufs                 = vb2_ioctl_reqbufs,
> +       .vidioc_create_bufs             = vb2_ioctl_create_bufs,
> +       .vidioc_prepare_buf             = vb2_ioctl_prepare_buf,
> +       .vidioc_querybuf                = vb2_ioctl_querybuf,
> +       .vidioc_qbuf                    = vb2_ioctl_qbuf,
> +       .vidioc_dqbuf                   = vb2_ioctl_dqbuf,
> +       .vidioc_expbuf                  = vb2_ioctl_expbuf,
> +       .vidioc_streamon                = vb2_ioctl_streamon,
> +       .vidioc_streamoff               = vb2_ioctl_streamoff,
> +
> +       .vidioc_log_status              = unicam_log_status,
> +       .vidioc_subscribe_event         = unicam_subscribe_event,
> +       .vidioc_unsubscribe_event       = v4l2_event_unsubscribe,
> +};
> +
> +/* unicam capture driver file operations */
> +static const struct v4l2_file_operations unicam_fops = {
> +       .owner          = THIS_MODULE,
> +       .open           = v4l2_fh_open,
> +       .release        = vb2_fop_release,
> +       .poll           = vb2_fop_poll,
> +       .unlocked_ioctl = video_ioctl2,
> +       .mmap           = vb2_fop_mmap,
> +};
> +
> +static int unicam_video_link_validate(struct media_link *link)
> +{
> +       struct video_device *vdev =
> +               media_entity_to_video_device(link->sink->entity);
> +       struct v4l2_subdev *sd =
> +               media_entity_to_v4l2_subdev(link->source->entity);
> +       struct unicam_node *node = video_get_drvdata(vdev);
> +       const u32 pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +                     : UNICAM_SD_PAD_SOURCE_METADATA;
> +       const struct v4l2_mbus_framefmt *format;
> +       struct v4l2_subdev_state *state;
> +       int ret = 0;
> +
> +       state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> +       format = v4l2_subdev_state_get_format(state, pad, 0);
> +       if (!format) {
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       if (is_image_node(node)) {
> +               const struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> +
> +               if (node->fmtinfo->code != format->code ||
> +                   fmt->height != format->height ||
> +                   fmt->width != format->width ||
> +                   fmt->field != format->field) {
> +                       dev_dbg(node->dev->dev,
> +                               "image: (%u x %u) 0x%08x %s != (%u x %u) 0x%08x %s\n",
> +                               fmt->width, fmt->height, node->fmtinfo->code,
> +                               v4l2_field_names[fmt->field],
> +                               format->width, format->height, format->code,
> +                               v4l2_field_names[format->field]);
> +                       ret = -EPIPE;
> +               };
> +       } else {
> +               const struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> +
> +               if (node->fmtinfo->code != format->code ||
> +                   fmt->height != format->height ||
> +                   fmt->width != format->width) {
> +                       dev_dbg(node->dev->dev,
> +                               "meta: (%u x %u) 0x%04x != (%u x %u) 0x%04x\n",
> +                               fmt->width, fmt->height, node->fmtinfo->code,
> +                               format->width, format->height, format->code);
> +                       ret = -EPIPE;
> +               };
> +       }
> +
> +out:
> +       v4l2_subdev_unlock_state(state);
> +       return ret;
> +}
> +
> +static const struct media_entity_operations unicam_video_media_ops = {
> +       .link_validate = unicam_video_link_validate,
> +};
> +
> +static void unicam_node_release(struct video_device *vdev)
> +{
> +       struct unicam_node *node = video_get_drvdata(vdev);
> +
> +       unicam_put(node->dev);
> +}
> +
> +static void unicam_set_default_format(struct unicam_node *node)
> +{
> +       if (is_image_node(node)) {
> +               struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> +
> +               node->fmtinfo = &unicam_image_formats[0];
> +               node->fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +
> +               v4l2_fill_pix_format(fmt, &unicam_default_image_format);
> +               fmt->pixelformat = node->fmtinfo->fourcc;
> +               unicam_calc_image_size_bpl(node->dev, node->fmtinfo, fmt);
> +       } else {
> +               struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> +
> +               node->fmtinfo = &unicam_meta_formats[0];
> +               node->fmt.type = V4L2_BUF_TYPE_META_CAPTURE;
> +
> +               fmt->dataformat = node->fmtinfo->fourcc;
> +               fmt->width = unicam_default_meta_format.width;
> +               fmt->height = unicam_default_meta_format.height;
> +               unicam_calc_meta_size_bpl(node->dev, node->fmtinfo, fmt);
> +       }
> +}
> +
> +static int unicam_register_node(struct unicam_device *unicam,
> +                               enum unicam_node_type type)
> +{
> +       const u32 pad_index = type == UNICAM_IMAGE_NODE
> +                           ? UNICAM_SD_PAD_SOURCE_IMAGE
> +                           : UNICAM_SD_PAD_SOURCE_METADATA;
> +       struct unicam_node *node = &unicam->node[type];
> +       struct video_device *vdev = &node->video_dev;
> +       struct vb2_queue *q = &node->buffer_queue;
> +       int ret;
> +
> +       node->dev = unicam_get(unicam);
> +       node->id = type;
> +
> +       spin_lock_init(&node->dma_queue_lock);
> +       mutex_init(&node->lock);
> +
> +       INIT_LIST_HEAD(&node->dma_queue);
> +
> +       /* Initialize the videobuf2 queue. */
> +       q->type = type == UNICAM_IMAGE_NODE ? V4L2_BUF_TYPE_VIDEO_CAPTURE
> +                                           : V4L2_BUF_TYPE_META_CAPTURE;
> +       q->io_modes = VB2_MMAP | VB2_DMABUF;
> +       q->drv_priv = node;
> +       q->ops = &unicam_video_qops;
> +       q->mem_ops = &vb2_dma_contig_memops;
> +       q->buf_struct_size = sizeof(struct unicam_buffer);
> +       q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> +       q->lock = &node->lock;
> +       q->min_queued_buffers = 1;
> +       q->dev = unicam->dev;
> +
> +       ret = vb2_queue_init(q);
> +       if (ret) {
> +               dev_err(unicam->dev, "vb2_queue_init() failed\n");
> +               goto err_unicam_put;
> +       }
> +
> +       /* Initialize the video device. */
> +       vdev->release = unicam_node_release;
> +       vdev->fops = &unicam_fops;
> +       vdev->ioctl_ops = &unicam_ioctl_ops;
> +       vdev->v4l2_dev = &unicam->v4l2_dev;
> +       vdev->vfl_dir = VFL_DIR_RX;
> +       vdev->queue = q;
> +       vdev->lock = &node->lock;
> +       vdev->device_caps = type == UNICAM_IMAGE_NODE
> +                         ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_META_CAPTURE;
> +       vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
> +       vdev->entity.ops = &unicam_video_media_ops;
> +
> +       snprintf(vdev->name, sizeof(vdev->name), "%s-%s", UNICAM_MODULE_NAME,
> +                type == UNICAM_IMAGE_NODE ? "image" : "embedded");
> +
> +       video_set_drvdata(vdev, node);
> +
> +       if (type == UNICAM_IMAGE_NODE)
> +               vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
> +
> +       node->pad.flags = MEDIA_PAD_FL_SINK;
> +
> +       ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
> +       if (ret)
> +               goto err_unicam_put;
> +
> +       node->dummy_buf.size = UNICAM_DUMMY_BUF_SIZE;
> +       node->dummy_buf_cpu_addr = dma_alloc_coherent(unicam->dev,
> +                                                     node->dummy_buf.size,
> +                                                     &node->dummy_buf.dma_addr,
> +                                                     GFP_KERNEL);
> +       if (!node->dummy_buf_cpu_addr) {
> +               dev_err(unicam->dev, "Unable to allocate dummy buffer.\n");
> +               ret = -ENOMEM;
> +               goto err_entity_cleanup;
> +       }
> +
> +       unicam_set_default_format(node);
> +
> +       ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> +       if (ret) {
> +               dev_err(unicam->dev, "Unable to register video device %s\n",
> +                       vdev->name);
> +               goto err_dma_free;
> +       }
> +
> +       node->registered = true;
> +
> +       ret = media_create_pad_link(&unicam->subdev.sd.entity,
> +                                   pad_index,
> +                                   &node->video_dev.entity,
> +                                   0,
> +                                   MEDIA_LNK_FL_ENABLED |
> +                                   MEDIA_LNK_FL_IMMUTABLE);
> +       if (ret) {
> +               /*
> +                * No need for cleanup, the caller will unregister the
> +                * video device, which will drop the reference on the
> +                * device and trigger the cleanup.
> +                */
> +               dev_err(unicam->dev, "Unable to create pad link for %s\n",
> +                       unicam->sensor.subdev->name);
> +               return ret;
> +       }
> +
> +       return 0;
> +
> +err_dma_free:
> +       dma_free_coherent(unicam->dev, node->dummy_buf.size,
> +                         node->dummy_buf_cpu_addr,
> +                         node->dummy_buf.dma_addr);
> +err_entity_cleanup:
> +       media_entity_cleanup(&vdev->entity);
> +err_unicam_put:
> +       unicam_put(unicam);
> +       return ret;
> +}
> +
> +static void unicam_unregister_nodes(struct unicam_device *unicam)
> +{
> +       unsigned int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +               struct unicam_node *node = &unicam->node[i];
> +
> +               if (node->dummy_buf_cpu_addr)
> +                       dma_free_coherent(unicam->dev, node->dummy_buf.size,
> +                                         node->dummy_buf_cpu_addr,
> +                                         node->dummy_buf.dma_addr);
> +
> +               if (node->registered) {
> +                       video_unregister_device(&node->video_dev);
> +                       node->registered = false;
> +               }
> +       }
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Power management
> + */
> +
> +static int unicam_runtime_resume(struct device *dev)
> +{
> +       struct unicam_device *unicam = dev_get_drvdata(dev);
> +       int ret;
> +
> +       ret = clk_set_min_rate(unicam->vpu_clock, UNICAM_MIN_VPU_CLOCK_RATE);
> +       if (ret) {
> +               dev_err(unicam->dev, "failed to set up VPU clock\n");
> +               return ret;
> +       }
> +
> +       ret = clk_prepare_enable(unicam->vpu_clock);
> +       if (ret) {
> +               dev_err(unicam->dev, "Failed to enable VPU clock: %d\n", ret);
> +               goto err_vpu_clock;
> +       }
> +
> +       ret = clk_set_rate(unicam->clock, 100 * 1000 * 1000);
> +       if (ret) {
> +               dev_err(unicam->dev, "failed to set up CSI clock\n");
> +               goto err_vpu_prepare;
> +       }
> +
> +       ret = clk_prepare_enable(unicam->clock);
> +       if (ret) {
> +               dev_err(unicam->dev, "Failed to enable CSI clock: %d\n", ret);
> +               goto err_vpu_prepare;
> +       }
> +
> +       return 0;
> +
> +err_vpu_prepare:
> +       clk_disable_unprepare(unicam->vpu_clock);
> +err_vpu_clock:
> +       if (clk_set_min_rate(unicam->vpu_clock, 0))
> +               dev_err(unicam->dev, "failed to reset the VPU clock\n");
> +
> +       return ret;
> +}
> +
> +static int unicam_runtime_suspend(struct device *dev)
> +{
> +       struct unicam_device *unicam = dev_get_drvdata(dev);
> +
> +       clk_disable_unprepare(unicam->clock);
> +
> +       if (clk_set_min_rate(unicam->vpu_clock, 0))
> +               dev_err(unicam->dev, "failed to reset the VPU clock\n");
> +
> +       clk_disable_unprepare(unicam->vpu_clock);
> +
> +       return 0;
> +}
> +
> +static const struct dev_pm_ops unicam_pm_ops = {
> +       RUNTIME_PM_OPS(unicam_runtime_suspend, unicam_runtime_resume, NULL)
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * V4L2 async notifier
> + */
> +
> +static int unicam_async_bound(struct v4l2_async_notifier *notifier,
> +                             struct v4l2_subdev *subdev,
> +                             struct v4l2_async_connection *asc)
> +{
> +       struct unicam_device *unicam = notifier_to_unicam_device(notifier);
> +       struct media_pad *sink = &unicam->subdev.pads[UNICAM_SD_PAD_SINK];
> +       struct media_pad *source;
> +       int ret;
> +
> +       dev_dbg(unicam->dev, "Using sensor %s for capture\n",
> +               subdev->name);
> +
> +       ret = v4l2_create_fwnode_links_to_pad(subdev, sink, MEDIA_LNK_FL_ENABLED |
> +                                             MEDIA_LNK_FL_IMMUTABLE);
> +       if (ret)
> +               return ret;
> +
> +       source = media_pad_remote_pad_unique(sink);
> +       if (!source) {
> +               dev_err(unicam->dev, "No connected sensor pad\n");
> +               return -ENOTCONN;
> +       }
> +
> +       unicam->sensor.subdev = subdev;
> +       unicam->sensor.pad = source;
> +
> +       return 0;
> +}
> +
> +static int unicam_async_complete(struct v4l2_async_notifier *notifier)
> +{
> +       struct unicam_device *unicam = notifier_to_unicam_device(notifier);
> +       int ret;
> +
> +       ret = unicam_register_node(unicam, UNICAM_IMAGE_NODE);
> +       if (ret) {
> +               dev_err(unicam->dev, "Unable to register image video device.\n");
> +               goto unregister;
> +       }
> +
> +       ret = unicam_register_node(unicam, UNICAM_METADATA_NODE);
> +       if (ret) {
> +               dev_err(unicam->dev, "Unable to register metadata video device.\n");
> +               goto unregister;
> +       }
> +
> +       ret = v4l2_device_register_subdev_nodes(&unicam->v4l2_dev);
> +       if (ret) {
> +               dev_err(unicam->dev, "Unable to register subdev nodes.\n");
> +               goto unregister;
> +       }
> +
> +       return 0;
> +
> +unregister:
> +       unicam_unregister_nodes(unicam);
> +       unicam_put(unicam);
> +
> +       return ret;
> +}
> +
> +static const struct v4l2_async_notifier_operations unicam_async_ops = {
> +       .bound = unicam_async_bound,
> +       .complete = unicam_async_complete,
> +};
> +
> +static int unicam_async_nf_init(struct unicam_device *unicam)
> +{
> +       struct v4l2_fwnode_endpoint ep = { };
> +       struct fwnode_handle *ep_handle;
> +       struct v4l2_async_connection *asc;
> +       int ret;
> +
> +       ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
> +                                  &unicam->max_data_lanes);
> +       if (ret < 0) {
> +               dev_err(unicam->dev, "Missing %s DT property\n",
> +                       "brcm,num-data-lanes");
> +               return -EINVAL;
> +       }
> +
> +       /* Get and parse the local endpoint. */
> +       ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
> +                                                   FWNODE_GRAPH_ENDPOINT_NEXT);
> +       if (!ep_handle) {
> +               dev_err(unicam->dev, "No endpoint found\n");
> +               return -ENODEV;
> +       }
> +
> +       ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
> +       if (ret) {
> +               dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
> +               goto error;
> +       }
> +
> +       unicam->bus_type = ep.bus_type;
> +
> +       switch (ep.bus_type) {
> +       case V4L2_MBUS_CSI2_DPHY: {
> +               unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
> +
> +               if (num_data_lanes != 1 && num_data_lanes != 2 &&
> +                   num_data_lanes != 4) {
> +                       dev_err(unicam->dev, "%u data lanes not supported\n",
> +                               num_data_lanes);
> +                       goto error;
> +               }
> +
> +               if (num_data_lanes > unicam->max_data_lanes) {
> +                       dev_err(unicam->dev,
> +                               "Endpoint uses %u data lanes when %u are supported\n",
> +                               num_data_lanes, unicam->max_data_lanes);
> +                       goto error;
> +               }
> +
> +               unicam->active_data_lanes = num_data_lanes;
> +               unicam->bus_flags = ep.bus.mipi_csi2.flags;
> +               break;
> +       }
> +
> +       case V4L2_MBUS_CCP2:
> +               unicam->max_data_lanes = 1;
> +               unicam->active_data_lanes = 1;
> +               unicam->bus_flags = ep.bus.mipi_csi1.strobe;
> +               break;
> +
> +       default:
> +               /* Unsupported bus type */
> +               dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
> +               goto error;
> +       }
> +
> +       /* Initialize and register the async notifier. */
> +       v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
> +
> +       asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
> +                                             struct v4l2_async_connection);
> +       fwnode_handle_put(ep_handle);
> +       ep_handle = NULL;
> +
> +       if (IS_ERR(asc)) {
> +               ret = PTR_ERR(asc);
> +               dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
> +                       ret);
> +               goto error;
> +       }
> +
> +       unicam->notifier.ops = &unicam_async_ops;
> +
> +       ret = v4l2_async_nf_register(&unicam->notifier);
> +       if (ret) {
> +               dev_err(unicam->dev, "Error registering device notifier: %d\n",
> +                       ret);
> +               goto error;
> +       }
> +
> +       return 0;
> +
> +error:
> +       fwnode_handle_put(ep_handle);
> +       return ret;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Probe & remove
> + */
> +
> +static int unicam_media_init(struct unicam_device *unicam)
> +{
> +       int ret;
> +
> +       unicam->mdev.dev = unicam->dev;
> +       strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
> +               sizeof(unicam->mdev.model));
> +       strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));
> +       unicam->mdev.hw_revision = 0;
> +
> +       media_device_init(&unicam->mdev);
> +
> +       unicam->v4l2_dev.mdev = &unicam->mdev;
> +
> +       ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
> +       if (ret < 0) {
> +               dev_err(unicam->dev, "Unable to register v4l2 device\n");
> +               goto err_media_cleanup;
> +       }
> +
> +       ret = media_device_register(&unicam->mdev);
> +       if (ret < 0) {
> +               dev_err(unicam->dev,
> +                       "Unable to register media-controller device\n");
> +               goto err_v4l2_unregister;
> +       }
> +
> +       return 0;
> +
> +err_v4l2_unregister:
> +       v4l2_device_unregister(&unicam->v4l2_dev);
> +err_media_cleanup:
> +       media_device_cleanup(&unicam->mdev);
> +       return ret;
> +}
> +
> +static int unicam_probe(struct platform_device *pdev)
> +{
> +       struct unicam_device *unicam;
> +       int ret;
> +
> +       unicam = kzalloc(sizeof(*unicam), GFP_KERNEL);
> +       if (!unicam)
> +               return -ENOMEM;
> +
> +       kref_init(&unicam->kref);
> +       unicam->dev = &pdev->dev;
> +       platform_set_drvdata(pdev, unicam);
> +
> +       unicam->base = devm_platform_ioremap_resource_byname(pdev, "unicam");
> +       if (IS_ERR(unicam->base)) {
> +               ret = PTR_ERR(unicam->base);
> +               goto err_unicam_put;
> +       }
> +
> +       unicam->clk_gate_base = devm_platform_ioremap_resource_byname(pdev, "cmi");
> +       if (IS_ERR(unicam->clk_gate_base)) {
> +               ret = PTR_ERR(unicam->clk_gate_base);
> +               goto err_unicam_put;
> +       }
> +
> +       unicam->clock = devm_clk_get(&pdev->dev, "lp");
> +       if (IS_ERR(unicam->clock)) {
> +               dev_err(unicam->dev, "Failed to get lp clock\n");
> +               ret = PTR_ERR(unicam->clock);
> +               goto err_unicam_put;
> +       }
> +
> +       unicam->vpu_clock = devm_clk_get(&pdev->dev, "vpu");
> +       if (IS_ERR(unicam->vpu_clock)) {
> +               dev_err(unicam->dev, "Failed to get vpu clock\n");
> +               ret = PTR_ERR(unicam->vpu_clock);
> +               goto err_unicam_put;
> +       }
> +
> +       ret = platform_get_irq(pdev, 0);
> +       if (ret <= 0) {
> +               dev_err(&pdev->dev, "No IRQ resource\n");
> +               ret = -EINVAL;
> +               goto err_unicam_put;
> +       }
> +
> +       ret = devm_request_irq(&pdev->dev, ret, unicam_isr, 0,
> +                              "unicam_capture0", unicam);
> +       if (ret) {
> +               dev_err(&pdev->dev, "Unable to request interrupt\n");
> +               ret = -EINVAL;
> +               goto err_unicam_put;
> +       }
> +
> +       /* Enable the block power domain. */
> +       pm_runtime_enable(&pdev->dev);
> +
> +       ret = unicam_media_init(unicam);
> +       if (ret)
> +               goto err_pm_runtime;
> +
> +       ret = unicam_subdev_init(unicam);
> +       if (ret)
> +               goto err_media_unregister;
> +
> +       ret = unicam_async_nf_init(unicam);
> +       if (ret)
> +               goto err_subdev_unregister;
> +
> +       return 0;
> +
> +err_subdev_unregister:
> +       unicam_subdev_cleanup(unicam);
> +err_media_unregister:
> +       media_device_unregister(&unicam->mdev);
> +err_pm_runtime:
> +       pm_runtime_disable(&pdev->dev);
> +err_unicam_put:
> +       unicam_put(unicam);
> +
> +       return ret;
> +}
> +
> +static int unicam_remove(struct platform_device *pdev)
> +{
> +       struct unicam_device *unicam = platform_get_drvdata(pdev);
> +
> +       unicam_unregister_nodes(unicam);
> +       v4l2_device_unregister(&unicam->v4l2_dev);
> +       media_device_unregister(&unicam->mdev);
> +       v4l2_async_nf_unregister(&unicam->notifier);
> +
> +       unicam_subdev_cleanup(unicam);
> +
> +       unicam_put(unicam);
> +
> +       pm_runtime_disable(&pdev->dev);
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id unicam_of_match[] = {
> +       { .compatible = "brcm,bcm2835-unicam", },
> +       { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, unicam_of_match);
> +
> +static struct platform_driver unicam_driver = {
> +       .probe          = unicam_probe,
> +       .remove         = unicam_remove,
> +       .driver = {
> +               .name   = UNICAM_MODULE_NAME,
> +               .pm     = pm_ptr(&unicam_pm_ops),
> +               .of_match_table = of_match_ptr(unicam_of_match),
> +       },
> +};
> +
> +module_platform_driver(unicam_driver);
> +
> +MODULE_AUTHOR("Dave Stevenson <[e-mail]>");
> +MODULE_DESCRIPTION("BCM2835 Unicam driver");
> +MODULE_LICENSE("GPL");

> --
> Regards,
>
> Laurent Pinchart
>

Laurent Pinchart March 21, 2024, 7:57 p.m. UTC | #8

Hi Naush,

On Wed, Mar 20, 2024 at 12:30:36PM +0000, Naushir Patuck wrote:
> On Fri, 1 Mar 2024 at 21:32, Laurent Pinchart wrote:
> >
> > From: Dave Stevenson <[e-mail]>
> >
> > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > It is represented as two video device nodes: unicam-image and
> > unicam-embedded which are connected to an internal subdev (named
> > unicam-subdev) in order to manage streams routing.
> >
> > Signed-off-by: Dave Stevenson <[e-mail]>
> > Co-developed-by: Naushir Patuck <[e-mail]>
> > Signed-off-by: Naushir Patuck <[e-mail]>
> > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > Co-developed-by: Laurent Pinchart <[e-mail]>
> > Signed-off-by: Laurent Pinchart <[e-mail]>
> > ---

[snip]

> > ---
> >  MAINTAINERS                                   |    1 +
> >  drivers/media/platform/Kconfig                |    1 +
> >  drivers/media/platform/Makefile               |    1 +
> >  drivers/media/platform/broadcom/Kconfig       |   23 +
> >  drivers/media/platform/broadcom/Makefile      |    3 +
> >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> >  7 files changed, 2891 insertions(+)
> >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> >  create mode 100644 drivers/media/platform/broadcom/Makefile
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c

[snip]

> > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > new file mode 100644
> > index 000000000000..716c89b8a217
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > @@ -0,0 +1,2607 @@

[snip]

> > +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> > +{
> > +       struct unicam_node *node = vb2_get_drv_priv(vq);
> > +       struct unicam_device *unicam = node->dev;
> > +       struct v4l2_subdev_state *state;
> > +       struct unicam_buffer *buf;
> > +       unsigned long flags;
> > +       int ret;
> > +       u32 pad, stream;
> > +       u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> > +                                            : UNICAM_SD_PAD_SOURCE_METADATA;
> > +
> > +       /* Look for the route for the given pad and stream. */
> > +       state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> > +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> > +                                                   remote_pad, 0,
> > +                                                   &pad, &stream);
> > +       v4l2_subdev_unlock_state(state);
> > +
> > +       if (ret)
> > +               goto err_return_buffers;
> > +
> > +       dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> > +               unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> > +               is_metadata_node(node) ? "metadata" : "image");
> > +
> > +       /* The metadata node can't be started alone. */
> > +       if (is_metadata_node(node)) {
> > +               if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> > +                       dev_err(unicam->dev,
> > +                               "Can't start metadata without image\n");
> > +                       ret = -EINVAL;
> > +                       goto err_return_buffers;
> > +               }
> 
> There's a slight change of behaviour in this function when compared to
> the downstream/BSP non-streams enabled driver.
> 
> In the BSP driver, if the embedded data node has been enabled, we wait
> for both image and embedded data nodes to have start_streaming()
> called before starting the sensor (see
> https://github.com/raspberrypi/linux/blob/c04af98514c26014a4f29ec87b3ece95626059bd/drivers/media/platform/bcm2835/bcm2835-unicam.c#L2559).
> This is also the same for the Pi 5 CFE driver.
> 
> With the logic in this function, we only wait for start_streaming() on
> the image node then start the sensor streaming immediately.  When
> start_streaming() for the embedded data node is subsequently called,
> we end up with the first N buffers missing and/or invalid as the HW
> channel is enabled while the sensor is streaming.  I noticed this when
> using libcamera where we start image then embedded node.  If I flip
> things around (start embedded first then image), everything works as
> expected.
> 
> Could we add back the test to ensure all nodes are streaming before
> starting the sensor?

Yes, I don't think the current implementation is good. I'm not sure why
the logic got changed, but I'll address it in the next version.

> > +
> > +               spin_lock_irqsave(&node->dma_queue_lock, flags);
> > +               buf = list_first_entry(&node->dma_queue,
> > +                                      struct unicam_buffer, list);
> > +               dev_dbg(unicam->dev, "buffer %p\n", buf);
> > +               node->cur_frm = buf;
> > +               node->next_frm = buf;
> > +               list_del(&buf->list);
> > +               spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > +
> > +               unicam_start_metadata(unicam, buf);
> > +               node->streaming = true;
> > +               return 0;
> > +       }
> > +
> > +       ret = pm_runtime_resume_and_get(unicam->dev);
> > +       if (ret < 0) {
> > +               dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> > +               goto err_return_buffers;
> > +       }
> > +
> > +       ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> > +       if (ret < 0) {
> > +               dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> > +               goto err_pm_put;
> > +       }
> > +
> > +       spin_lock_irqsave(&node->dma_queue_lock, flags);
> > +       buf = list_first_entry(&node->dma_queue,
> > +                              struct unicam_buffer, list);
> > +       dev_dbg(unicam->dev, "buffer %p\n", buf);
> > +       node->cur_frm = buf;
> > +       node->next_frm = buf;
> > +       list_del(&buf->list);
> > +       spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> > +
> > +       unicam_start_rx(unicam, buf);
> > +
> > +       ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> > +       if (ret < 0) {
> > +               dev_err(unicam->dev, "stream on failed in subdev\n");
> > +               goto error_pipeline;
> > +       }
> > +
> > +       node->streaming = true;
> > +
> > +       return 0;
> > +
> > +error_pipeline:
> > +       video_device_pipeline_stop(&node->video_dev);
> > +err_pm_put:
> > +       pm_runtime_put_sync(unicam->dev);
> > +err_return_buffers:
> > +       unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> > +       return ret;
> > +}

[snip]

Jean-Michel Hautbois March 22, 2024, 8:40 a.m. UTC | #9

Hi Laurent, Naush,

On 21/03/2024 20:57, Laurent Pinchart wrote:
> Hi Naush,
> 
> On Wed, Mar 20, 2024 at 12:30:36PM +0000, Naushir Patuck wrote:
>> On Fri, 1 Mar 2024 at 21:32, Laurent Pinchart wrote:
>>>
>>> From: Dave Stevenson <[e-mail]>
>>>
>>> Add a driver for the Unicam camera receiver block on BCM283x processors.
>>> It is represented as two video device nodes: unicam-image and
>>> unicam-embedded which are connected to an internal subdev (named
>>> unicam-subdev) in order to manage streams routing.
>>>
>>> Signed-off-by: Dave Stevenson <[e-mail]>
>>> Co-developed-by: Naushir Patuck <[e-mail]>
>>> Signed-off-by: Naushir Patuck <[e-mail]>
>>> Co-developed-by: Jean-Michel Hautbois <[e-mail]>
>>> Signed-off-by: Jean-Michel Hautbois <[e-mail]>
>>> Co-developed-by: Laurent Pinchart <[e-mail]>
>>> Signed-off-by: Laurent Pinchart <[e-mail]>
>>> ---
> 
> [snip]
> 
>>> ---
>>>   MAINTAINERS                                   |    1 +
>>>   drivers/media/platform/Kconfig                |    1 +
>>>   drivers/media/platform/Makefile               |    1 +
>>>   drivers/media/platform/broadcom/Kconfig       |   23 +
>>>   drivers/media/platform/broadcom/Makefile      |    3 +
>>>   .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
>>>   .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
>>>   7 files changed, 2891 insertions(+)
>>>   create mode 100644 drivers/media/platform/broadcom/Kconfig
>>>   create mode 100644 drivers/media/platform/broadcom/Makefile
>>>   create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
>>>   create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> 
> [snip]
> 
>>> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
>>> new file mode 100644
>>> index 000000000000..716c89b8a217
>>> --- /dev/null
>>> +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
>>> @@ -0,0 +1,2607 @@
> 
> [snip]
> 
>>> +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
>>> +{
>>> +       struct unicam_node *node = vb2_get_drv_priv(vq);
>>> +       struct unicam_device *unicam = node->dev;
>>> +       struct v4l2_subdev_state *state;
>>> +       struct unicam_buffer *buf;
>>> +       unsigned long flags;
>>> +       int ret;
>>> +       u32 pad, stream;
>>> +       u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
>>> +                                            : UNICAM_SD_PAD_SOURCE_METADATA;
>>> +
>>> +       /* Look for the route for the given pad and stream. */
>>> +       state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
>>> +       ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
>>> +                                                   remote_pad, 0,
>>> +                                                   &pad, &stream);
>>> +       v4l2_subdev_unlock_state(state);
>>> +
>>> +       if (ret)
>>> +               goto err_return_buffers;
>>> +
>>> +       dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
>>> +               unicam->subdev.sd.name, pad, stream, remote_pad, 0,
>>> +               is_metadata_node(node) ? "metadata" : "image");
>>> +
>>> +       /* The metadata node can't be started alone. */
>>> +       if (is_metadata_node(node)) {
>>> +               if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
>>> +                       dev_err(unicam->dev,
>>> +                               "Can't start metadata without image\n");
>>> +                       ret = -EINVAL;
>>> +                       goto err_return_buffers;
>>> +               }
>>
>> There's a slight change of behaviour in this function when compared to
>> the downstream/BSP non-streams enabled driver.
>>
>> In the BSP driver, if the embedded data node has been enabled, we wait
>> for both image and embedded data nodes to have start_streaming()
>> called before starting the sensor (see
>> https://github.com/raspberrypi/linux/blob/c04af98514c26014a4f29ec87b3ece95626059bd/drivers/media/platform/bcm2835/bcm2835-unicam.c#L2559).
>> This is also the same for the Pi 5 CFE driver.
>>
>> With the logic in this function, we only wait for start_streaming() on
>> the image node then start the sensor streaming immediately.  When
>> start_streaming() for the embedded data node is subsequently called,
>> we end up with the first N buffers missing and/or invalid as the HW
>> channel is enabled while the sensor is streaming.  I noticed this when
>> using libcamera where we start image then embedded node.  If I flip
>> things around (start embedded first then image), everything works as
>> expected.
>>
>> Could we add back the test to ensure all nodes are streaming before
>> starting the sensor?
> 
> Yes, I don't think the current implementation is good. I'm not sure why
> the logic got changed, but I'll address it in the next version.
> 

I think I did it in v4. The aim of this change was to be able to start 
streaming on the image node even if the metadata node is not started. 
The opposite was not to be possible, so if the metadata node is started, 
then the image node must be started for streaming to begin. The 
downstream logic is that both nodes must always be started, but at the 
time of v4, not everything was ready for this, if I remember correctly.

JM

>>> +
>>> +               spin_lock_irqsave(&node->dma_queue_lock, flags);
>>> +               buf = list_first_entry(&node->dma_queue,
>>> +                                      struct unicam_buffer, list);
>>> +               dev_dbg(unicam->dev, "buffer %p\n", buf);
>>> +               node->cur_frm = buf;
>>> +               node->next_frm = buf;
>>> +               list_del(&buf->list);
>>> +               spin_unlock_irqrestore(&node->dma_queue_lock, flags);
>>> +
>>> +               unicam_start_metadata(unicam, buf);
>>> +               node->streaming = true;
>>> +               return 0;
>>> +       }
>>> +
>>> +       ret = pm_runtime_resume_and_get(unicam->dev);
>>> +       if (ret < 0) {
>>> +               dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
>>> +               goto err_return_buffers;
>>> +       }
>>> +
>>> +       ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
>>> +       if (ret < 0) {
>>> +               dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
>>> +               goto err_pm_put;
>>> +       }
>>> +
>>> +       spin_lock_irqsave(&node->dma_queue_lock, flags);
>>> +       buf = list_first_entry(&node->dma_queue,
>>> +                              struct unicam_buffer, list);
>>> +       dev_dbg(unicam->dev, "buffer %p\n", buf);
>>> +       node->cur_frm = buf;
>>> +       node->next_frm = buf;
>>> +       list_del(&buf->list);
>>> +       spin_unlock_irqrestore(&node->dma_queue_lock, flags);
>>> +
>>> +       unicam_start_rx(unicam, buf);
>>> +
>>> +       ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
>>> +       if (ret < 0) {
>>> +               dev_err(unicam->dev, "stream on failed in subdev\n");
>>> +               goto error_pipeline;
>>> +       }
>>> +
>>> +       node->streaming = true;
>>> +
>>> +       return 0;
>>> +
>>> +error_pipeline:
>>> +       video_device_pipeline_stop(&node->video_dev);
>>> +err_pm_put:
>>> +       pm_runtime_put_sync(unicam->dev);
>>> +err_return_buffers:
>>> +       unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
>>> +       return ret;
>>> +}
> 
> [snip]
>

Sakari Ailus March 25, 2024, 6:36 p.m. UTC | #10

Hi Laurent,

On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> From: Dave Stevenson <[e-mail]>
> 
> Add a driver for the Unicam camera receiver block on BCM283x processors.
> It is represented as two video device nodes: unicam-image and
> unicam-embedded which are connected to an internal subdev (named
> unicam-subdev) in order to manage streams routing.
> 
> Signed-off-by: Dave Stevenson <[e-mail]>
> Co-developed-by: Naushir Patuck <[e-mail]>
> Signed-off-by: Naushir Patuck <[e-mail]>
> Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> Co-developed-by: Laurent Pinchart <[e-mail]>
> Signed-off-by: Laurent Pinchart <[e-mail]>

Thanks for submitting this, it's the cleanest and neatest Unicom driver
I've ever seen!

Some mostly unimportant comments below, however the bus-type issue needs to
be addressed.

> ---
> Changes since v5:
> 
> - Move to drivers/media/platform/broadcom/
> - Port to the upstream V4L2 streams API
> - Rebase on latest metadata API proposal
> - Add missing error message
> - Drop unneeded documentation block for unicam_isr()
> - Drop unneeded dev_dbg() and dev_err() messages
> - Drop unneeded streams_mask and fmt checks
> - Drop unused unicam_sd_pad_is_sink()
> - Drop unneeded includes
> - Drop v4l2_ctrl_subscribe_event() call
> - Use pm_runtime_resume_and_get()
> - Indentation and line wrap fixes
> - Let the framework set bus_info
> - Use v4l2_fwnode_endpoint_parse()
> - Fix media device cleanup
> - Drop lane reordering checks
> - Fix subdev state locking
> - Drop extra debug messages
> - Move clock handling to runtime PM handlers
> - Reorder functions
> - Rename init functions for more clarity
> - Initialize runtime PM earlier
> - Clarify error messages
> - Simplify subdev init with local variable
> - Fix subdev cleanup
> - Fix typos and indentation
> - Don't initialize local variables needlessly
> - Simplify num lanes check
> - Fix metadata handling in subdev set_fmt
> - Drop manual fallback to .s_stream()
> - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> - Simplify unicam_set_default_format()
> - Fix default format settings
> - Add busy check in unicam_s_fmt_meta()
> - Add missing \n at end of format strings
> - Fix metadata handling in subdev set_fmt
> - Fix locking when starting streaming
> - Return buffers from start streaming fails
> - Fix format validation for metadata node
> - Use video_device_pipeline_{start,stop}() helpers
> - Simplify format enumeration
> - Drop unset variable
> - Update MAINTAINERS entry
> - Update to the upstream v4l2_async_nf API
> - Update to the latest subdev routing API
> - Update to the latest subdev state API
> - Move from subdev .init_cfg() to .init_state()
> - Update to the latest videobuf2 API
> - Fix v4l2_subdev_enable_streams() error check
> - Use correct pad for the connected subdev
> - Return buffers to vb2 when start streaming fails
> - Improve debugging in start streaming handler
> - Simplify DMA address management
> - Drop comment about bcm2835-camera driver
> - Clarify comments that explain min/max sizes
> - Pass v4l2_pix_format to unicam_try_fmt()
> - Drop unneeded local variables
> - Rename image-related constants and functions
> - Turn unicam_fmt.metadata_fmt into bool
> - Rename unicam_fmt to unicam_format_info
> - Rename unicam_format_info variables to fmtinfo
> - Rename unicam_node.v_fmt to fmt
> - Add metadata formats for RAW10, RAW12 and RAW14
> - Make metadata formats line-based
> - Validate format on metadata video device
> - Add Co-devlopped-by tags
> 
> Changes since v3:
> 
> - Add the vendor prefix for DT name
> - Use the reg-names in DT parsing
> - Remove MAINTAINERS entry
> 
> Changes since v2:
> 
> - Change code organization
> - Remove unused variables
> - Correct the fmt_meta functions
> - Rewrite the start/stop streaming
>   - You can now start the image node alone, but not the metadata one
>   - The buffers are allocated per-node
>   - only the required stream is started, if the route exists and is
>     enabled
> - Prefix the macros with UNICAM_ to not have too generic names
> - Drop colorspace support
> 
> Changes since v1:
> 
> - Replace the unicam_{info,debug,error} macros with dev_*()
> ---
>  MAINTAINERS                                   |    1 +
>  drivers/media/platform/Kconfig                |    1 +
>  drivers/media/platform/Makefile               |    1 +
>  drivers/media/platform/broadcom/Kconfig       |   23 +
>  drivers/media/platform/broadcom/Makefile      |    3 +
>  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
>  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
>  7 files changed, 2891 insertions(+)
>  create mode 100644 drivers/media/platform/broadcom/Kconfig
>  create mode 100644 drivers/media/platform/broadcom/Makefile
>  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
>  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e50a59654e6e..cc350729f467 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4002,6 +4002,7 @@ M:	Raspberry Pi Kernel Maintenance <[e-mail]>
>  L:	[e-mail]
>  S:	Maintained
>  F:	Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> +F:	drivers/media/platform/bcm2835/
>  
>  BROADCOM BCM47XX MIPS ARCHITECTURE
>  M:	Hauke Mehrtens <[e-mail]>
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index 91e54215de3a..2d79bfc68c15 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
>  source "drivers/media/platform/amphion/Kconfig"
>  source "drivers/media/platform/aspeed/Kconfig"
>  source "drivers/media/platform/atmel/Kconfig"
> +source "drivers/media/platform/broadcom/Kconfig"
>  source "drivers/media/platform/cadence/Kconfig"
>  source "drivers/media/platform/chips-media/Kconfig"
>  source "drivers/media/platform/intel/Kconfig"
> diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> index 3296ec1ebe16..da17301f7439 100644
> --- a/drivers/media/platform/Makefile
> +++ b/drivers/media/platform/Makefile
> @@ -10,6 +10,7 @@ obj-y += amlogic/
>  obj-y += amphion/
>  obj-y += aspeed/
>  obj-y += atmel/
> +obj-y += broadcom/
>  obj-y += cadence/
>  obj-y += chips-media/
>  obj-y += intel/
> diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> new file mode 100644
> index 000000000000..cc2c9afcc948
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/Kconfig
> @@ -0,0 +1,23 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +config VIDEO_BCM2835_UNICAM
> +	tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> +	depends on ARCH_BCM2835 || COMPILE_TEST
> +	depends on PM
> +	depends on VIDEO_DEV
> +	select MEDIA_CONTROLLER
> +	select V4L2_FWNODE
> +	select VIDEO_V4L2_SUBDEV_API
> +	select VIDEOBUF2_DMA_CONTIG
> +	help
> +	  Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> +	  This is a V4L2 driver that controls the CSI-2 receiver directly,
> +	  independently from the VC4 firmware.
> +
> +	  This driver is mutually exclusive with the use of bcm2835-camera. The
> +	  firmware will disable all access to the peripheral from within the
> +	  firmware if it finds a DT node using it, and bcm2835-camera will
> +	  therefore fail to probe.
> +
> +	  To compile this driver as a module, choose M here. The module will be
> +	  called bcm2835-unicam.
> diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> new file mode 100644
> index 000000000000..03d2045aba2e
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> new file mode 100644
> index 000000000000..84775fd2fac5
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> @@ -0,0 +1,255 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +/*
> + * Copyright (C) 2017-2020 Raspberry Pi Trading.

Anything up to 2024?


> + * Dave Stevenson <[e-mail]>
> + */
> +
> +#ifndef VC4_REGS_UNICAM_H
> +#define VC4_REGS_UNICAM_H
> +
> +#include <linux/bits.h>
> +
> +/*
> + * The following values are taken from files found within the code drop
> + * made by Broadcom for the BCM21553 Graphics Driver, predominantly in
> + * brcm_usrlib/dag/vmcsx/vcinclude/hardware_vc4.h.
> + * They have been modified to be only the register offset.
> + */
> +#define UNICAM_CTRL		0x000
> +#define UNICAM_STA		0x004
> +#define UNICAM_ANA		0x008
> +#define UNICAM_PRI		0x00c
> +#define UNICAM_CLK		0x010
> +#define UNICAM_CLT		0x014
> +#define UNICAM_DAT0		0x018
> +#define UNICAM_DAT1		0x01c
> +#define UNICAM_DAT2		0x020
> +#define UNICAM_DAT3		0x024
> +#define UNICAM_DLT		0x028
> +#define UNICAM_CMP0		0x02c
> +#define UNICAM_CMP1		0x030
> +#define UNICAM_CAP0		0x034
> +#define UNICAM_CAP1		0x038
> +#define UNICAM_ICTL		0x100
> +#define UNICAM_ISTA		0x104
> +#define UNICAM_IDI0		0x108
> +#define UNICAM_IPIPE		0x10c
> +#define UNICAM_IBSA0		0x110
> +#define UNICAM_IBEA0		0x114
> +#define UNICAM_IBLS		0x118
> +#define UNICAM_IBWP		0x11c
> +#define UNICAM_IHWIN		0x120
> +#define UNICAM_IHSTA		0x124
> +#define UNICAM_IVWIN		0x128
> +#define UNICAM_IVSTA		0x12c
> +#define UNICAM_ICC		0x130
> +#define UNICAM_ICS		0x134
> +#define UNICAM_IDC		0x138
> +#define UNICAM_IDPO		0x13c
> +#define UNICAM_IDCA		0x140
> +#define UNICAM_IDCD		0x144
> +#define UNICAM_IDS		0x148
> +#define UNICAM_DCS		0x200
> +#define UNICAM_DBSA0		0x204
> +#define UNICAM_DBEA0		0x208
> +#define UNICAM_DBWP		0x20c
> +#define UNICAM_DBCTL		0x300
> +#define UNICAM_IBSA1		0x304
> +#define UNICAM_IBEA1		0x308
> +#define UNICAM_IDI1		0x30c
> +#define UNICAM_DBSA1		0x310
> +#define UNICAM_DBEA1		0x314
> +#define UNICAM_MISC		0x400
> +
> +/*
> + * The following bitmasks are from the kernel released by Broadcom
> + * for Android - https://android.googlesource.com/kernel/bcm/
> + * The Rhea, Hawaii, and Java chips all contain the same VideoCore4
> + * Unicam block as BCM2835, as defined in eg
> + * arch/arm/mach-rhea/include/mach/rdb_A0/brcm_rdb_cam.h and similar.
> + * Values reworked to use the kernel BIT and GENMASK macros.
> + *
> + * Some of the bit mnenomics have been amended to match the datasheet.
> + */
> +/* UNICAM_CTRL Register */
> +#define UNICAM_CPE		BIT(0)
> +#define UNICAM_MEM		BIT(1)
> +#define UNICAM_CPR		BIT(2)
> +#define UNICAM_CPM_MASK		GENMASK(3, 3)
> +#define UNICAM_CPM_CSI2		0
> +#define UNICAM_CPM_CCP2		1
> +#define UNICAM_SOE		BIT(4)
> +#define UNICAM_DCM_MASK		GENMASK(5, 5)
> +#define UNICAM_DCM_STROBE	0
> +#define UNICAM_DCM_DATA		1
> +#define UNICAM_SLS		BIT(6)
> +#define UNICAM_PFT_MASK		GENMASK(11, 8)
> +#define UNICAM_OET_MASK		GENMASK(20, 12)
> +
> +/* UNICAM_STA Register */
> +#define UNICAM_SYN		BIT(0)
> +#define UNICAM_CS		BIT(1)
> +#define UNICAM_SBE		BIT(2)
> +#define UNICAM_PBE		BIT(3)
> +#define UNICAM_HOE		BIT(4)
> +#define UNICAM_PLE		BIT(5)
> +#define UNICAM_SSC		BIT(6)
> +#define UNICAM_CRCE		BIT(7)
> +#define UNICAM_OES		BIT(8)
> +#define UNICAM_IFO		BIT(9)
> +#define UNICAM_OFO		BIT(10)
> +#define UNICAM_BFO		BIT(11)
> +#define UNICAM_DL		BIT(12)
> +#define UNICAM_PS		BIT(13)
> +#define UNICAM_IS		BIT(14)
> +#define UNICAM_PI0		BIT(15)
> +#define UNICAM_PI1		BIT(16)
> +#define UNICAM_FSI_S		BIT(17)
> +#define UNICAM_FEI_S		BIT(18)
> +#define UNICAM_LCI_S		BIT(19)
> +#define UNICAM_BUF0_RDY		BIT(20)
> +#define UNICAM_BUF0_NO		BIT(21)
> +#define UNICAM_BUF1_RDY		BIT(22)
> +#define UNICAM_BUF1_NO		BIT(23)
> +#define UNICAM_DI		BIT(24)
> +
> +#define UNICAM_STA_MASK_ALL \
> +		(UNICAM_DL | \
> +		UNICAM_SBE | \

This and the lines below should start at right of the opening parenthesis,
not at it.

> +		UNICAM_PBE | \
> +		UNICAM_HOE | \
> +		UNICAM_PLE | \
> +		UNICAM_SSC | \
> +		UNICAM_CRCE | \
> +		UNICAM_IFO | \
> +		UNICAM_OFO | \
> +		UNICAM_PS | \
> +		UNICAM_PI0 | \
> +		UNICAM_PI1)
> +
> +/* UNICAM_ANA Register */
> +#define UNICAM_APD		BIT(0)
> +#define UNICAM_BPD		BIT(1)
> +#define UNICAM_AR		BIT(2)
> +#define UNICAM_DDL		BIT(3)
> +#define UNICAM_CTATADJ_MASK	GENMASK(7, 4)
> +#define UNICAM_PTATADJ_MASK	GENMASK(11, 8)
> +
> +/* UNICAM_PRI Register */
> +#define UNICAM_PE		BIT(0)
> +#define UNICAM_PT_MASK		GENMASK(2, 1)
> +#define UNICAM_NP_MASK		GENMASK(7, 4)
> +#define UNICAM_PP_MASK		GENMASK(11, 8)
> +#define UNICAM_BS_MASK		GENMASK(15, 12)
> +#define UNICAM_BL_MASK		GENMASK(17, 16)
> +
> +/* UNICAM_CLK Register */
> +#define UNICAM_CLE		BIT(0)
> +#define UNICAM_CLPD		BIT(1)
> +#define UNICAM_CLLPE		BIT(2)
> +#define UNICAM_CLHSE		BIT(3)
> +#define UNICAM_CLTRE		BIT(4)
> +#define UNICAM_CLAC_MASK	GENMASK(8, 5)
> +#define UNICAM_CLSTE		BIT(29)
> +
> +/* UNICAM_CLT Register */
> +#define UNICAM_CLT1_MASK	GENMASK(7, 0)
> +#define UNICAM_CLT2_MASK	GENMASK(15, 8)
> +
> +/* UNICAM_DATn Registers */
> +#define UNICAM_DLE		BIT(0)
> +#define UNICAM_DLPD		BIT(1)
> +#define UNICAM_DLLPE		BIT(2)
> +#define UNICAM_DLHSE		BIT(3)
> +#define UNICAM_DLTRE		BIT(4)
> +#define UNICAM_DLSM		BIT(5)
> +#define UNICAM_DLFO		BIT(28)
> +#define UNICAM_DLSTE		BIT(29)
> +
> +#define UNICAM_DAT_MASK_ALL	(UNICAM_DLSTE | UNICAM_DLFO)
> +
> +/* UNICAM_DLT Register */
> +#define UNICAM_DLT1_MASK	GENMASK(7, 0)
> +#define UNICAM_DLT2_MASK	GENMASK(15, 8)
> +#define UNICAM_DLT3_MASK	GENMASK(23, 16)
> +
> +/* UNICAM_ICTL Register */
> +#define UNICAM_FSIE		BIT(0)
> +#define UNICAM_FEIE		BIT(1)
> +#define UNICAM_IBOB		BIT(2)
> +#define UNICAM_FCM		BIT(3)
> +#define UNICAM_TFC		BIT(4)
> +#define UNICAM_LIP_MASK		GENMASK(6, 5)
> +#define UNICAM_LCIE_MASK	GENMASK(28, 16)
> +
> +/* UNICAM_IDI0/1 Register */
> +#define UNICAM_ID0_MASK		GENMASK(7, 0)
> +#define UNICAM_ID1_MASK		GENMASK(15, 8)
> +#define UNICAM_ID2_MASK		GENMASK(23, 16)
> +#define UNICAM_ID3_MASK		GENMASK(31, 24)
> +
> +/* UNICAM_ISTA Register */
> +#define UNICAM_FSI		BIT(0)
> +#define UNICAM_FEI		BIT(1)
> +#define UNICAM_LCI		BIT(2)
> +
> +#define UNICAM_ISTA_MASK_ALL	(UNICAM_FSI | UNICAM_FEI | UNICAM_LCI)
> +
> +/* UNICAM_IPIPE Register */
> +#define UNICAM_PUM_MASK		GENMASK(2, 0)
> +/* Unpacking modes */
> +#define UNICAM_PUM_NONE		0
> +#define UNICAM_PUM_UNPACK6	1
> +#define UNICAM_PUM_UNPACK7	2
> +#define UNICAM_PUM_UNPACK8	3
> +#define UNICAM_PUM_UNPACK10	4
> +#define UNICAM_PUM_UNPACK12	5
> +#define UNICAM_PUM_UNPACK14	6
> +#define UNICAM_PUM_UNPACK16	7
> +#define UNICAM_DDM_MASK		GENMASK(6, 3)
> +#define UNICAM_PPM_MASK		GENMASK(9, 7)
> +/* Packing modes */
> +#define UNICAM_PPM_NONE		0
> +#define UNICAM_PPM_PACK8	1
> +#define UNICAM_PPM_PACK10	2
> +#define UNICAM_PPM_PACK12	3
> +#define UNICAM_PPM_PACK14	4
> +#define UNICAM_PPM_PACK16	5
> +#define UNICAM_DEM_MASK		GENMASK(11, 10)
> +#define UNICAM_DEBL_MASK	GENMASK(14, 12)
> +#define UNICAM_ICM_MASK		GENMASK(16, 15)
> +#define UNICAM_IDM_MASK		GENMASK(17, 17)
> +
> +/* UNICAM_ICC Register */
> +#define UNICAM_ICFL_MASK	GENMASK(4, 0)
> +#define UNICAM_ICFH_MASK	GENMASK(9, 5)
> +#define UNICAM_ICST_MASK	GENMASK(12, 10)
> +#define UNICAM_ICLT_MASK	GENMASK(15, 13)
> +#define UNICAM_ICLL_MASK	GENMASK(31, 16)
> +
> +/* UNICAM_DCS Register */
> +#define UNICAM_DIE		BIT(0)
> +#define UNICAM_DIM		BIT(1)
> +#define UNICAM_DBOB		BIT(3)
> +#define UNICAM_FDE		BIT(4)
> +#define UNICAM_LDP		BIT(5)
> +#define UNICAM_EDL_MASK		GENMASK(15, 8)
> +
> +/* UNICAM_DBCTL Register */
> +#define UNICAM_DBEN		BIT(0)
> +#define UNICAM_BUF0_IE		BIT(1)
> +#define UNICAM_BUF1_IE		BIT(2)
> +
> +/* UNICAM_CMP[0,1] register */
> +#define UNICAM_PCE		BIT(31)
> +#define UNICAM_GI		BIT(9)
> +#define UNICAM_CPH		BIT(8)
> +#define UNICAM_PCVC_MASK	GENMASK(7, 6)
> +#define UNICAM_PCDT_MASK	GENMASK(5, 0)
> +
> +/* UNICAM_MISC register */
> +#define UNICAM_FL0		BIT(6)
> +#define UNICAM_FL1		BIT(9)
> +
> +#endif
> diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> new file mode 100644
> index 000000000000..716c89b8a217
> --- /dev/null
> +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> @@ -0,0 +1,2607 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * BCM283x / BCM271x Unicam Capture Driver
> + *
> + * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
> + *
> + * Dave Stevenson <[e-mail]>
> + *
> + * Based on TI am437x driver by
> + *   Benoit Parrot <[e-mail]>
> + *   Lad, Prabhakar <[e-mail]>
> + *
> + * and TI CAL camera interface driver by
> + *    Benoit Parrot <[e-mail]>
> + *
> + *
> + * There are two camera drivers in the kernel for BCM283x - this one and
> + * bcm2835-camera (currently in staging).
> + *
> + * This driver directly controls the Unicam peripheral - there is no
> + * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
> + * and writes it into SDRAM. The only potential processing options are to
> + * repack Bayer data into an alternate format, and applying windowing. The
> + * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
> + * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
> + * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
> + * where the relevant formats are defined, and will automatically configure the
> + * repacking as required. Support for windowing may be added later.
> + *
> + * It should be possible to connect this driver to any sensor with a suitable
> + * output interface and V4L2 subdevice driver.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +#include <linux/videodev2.h>
> +
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-dev.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-mc.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "bcm2835-unicam-regs.h"
> +
> +#define UNICAM_MODULE_NAME		"unicam"
> +
> +/*
> + * Unicam must request a minimum of 250Mhz from the VPU clock.
> + * Otherwise the input FIFOs overrun and cause image corruption.
> + */
> +#define UNICAM_MIN_VPU_CLOCK_RATE	(250 * 1000 * 1000)
> +
> +/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
> +#define UNICAM_DMA_BPL_ALIGNMENT	16
> +
> +/*
> + * The image stride is stored in a 16 bit register, and needs to be aligned to
> + * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
> + * constraint on its input, set the image stride alignment to 32 bytes here as
> + * well to avoid incompatible configurations.
> + */
> +#define UNICAM_IMAGE_BPL_ALIGNMENT	32
> +#define UNICAM_IMAGE_MAX_BPL		((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)

Bit shifted values should be unsigned.

> +
> +/*
> + * Max width is therefore determined by the max stride divided by the number of
> + * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
> + * so adopt a square image for want of anything better.
> + */
> +#define UNICAM_IMAGE_MIN_WIDTH		16
> +#define UNICAM_IMAGE_MIN_HEIGHT		16
> +#define UNICAM_IMAGE_MAX_WIDTH		(UNICAM_IMAGE_MAX_BPL / 4)
> +#define UNICAM_IMAGE_MAX_HEIGHT		UNICAM_IMAGE_MAX_WIDTH
> +
> +/*
> + * There's no intrinsic limits on the width and height for embedded dat. Use
> + * the same maximum values as for the image, to avoid overflows in the image
> + * size computation.
> + */
> +#define UNICAM_META_MIN_WIDTH		1
> +#define UNICAM_META_MIN_HEIGHT		1
> +#define UNICAM_META_MAX_WIDTH		UNICAM_IMAGE_MAX_WIDTH
> +#define UNICAM_META_MAX_HEIGHT		UNICAM_IMAGE_MAX_HEIGHT
> +
> +/*
> + * Size of the dummy buffer. Can be any size really, but the DMA
> + * allocation works in units of page sizes.
> + */
> +#define UNICAM_DUMMY_BUF_SIZE		PAGE_SIZE
> +
> +#define UNICAM_SD_PAD_SINK		0
> +#define UNICAM_SD_PAD_SOURCE_IMAGE	1
> +#define UNICAM_SD_PAD_SOURCE_METADATA	2
> +#define UNICAM_SD_NUM_PADS		(1 + UNICAM_SD_PAD_SOURCE_METADATA)
> +
> +enum unicam_node_type {
> +	UNICAM_IMAGE_NODE,
> +	UNICAM_METADATA_NODE,
> +	UNICAM_MAX_NODES
> +};
> +
> +/*
> + * struct unicam_format_info - Unicam media bus format information
> + * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
> + * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
> + * out to 16bpp. 0 if n/a.
> + * @code: V4L2 media bus format code.
> + * @depth: Bits per pixel as delivered from the source.
> + * @csi_dt: CSI data type.
> + * @metadata_fmt: This format only applies to the metadata pad.
> + */
> +struct unicam_format_info {
> +	u32	fourcc;
> +	u32	unpacked_fourcc;
> +	u32	code;
> +	u8	depth;
> +	u8	csi_dt;
> +	bool	metadata_fmt;
> +};
> +
> +struct unicam_buffer {
> +	struct vb2_v4l2_buffer vb;
> +	struct list_head list;
> +	dma_addr_t dma_addr;
> +	unsigned int size;
> +};
> +
> +static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
> +{
> +	return container_of(vb, struct unicam_buffer, vb.vb2_buf);
> +}
> +
> +struct unicam_node {
> +	bool registered;
> +	bool streaming;
> +	unsigned int id;
> +
> +	/* Pointer to the current v4l2_buffer */
> +	struct unicam_buffer *cur_frm;
> +	/* Pointer to the next v4l2_buffer */
> +	struct unicam_buffer *next_frm;
> +	/* video capture */
> +	const struct unicam_format_info *fmtinfo;
> +	/* Used to store current pixel format */
> +	struct v4l2_format fmt;
> +	/* Buffer queue used in video-buf */
> +	struct vb2_queue buffer_queue;
> +	/* Queue of filled frames */
> +	struct list_head dma_queue;
> +	/* IRQ lock for DMA queue */
> +	spinlock_t dma_queue_lock;
> +	/* lock used to access this structure */
> +	struct mutex lock;
> +	/* Identifies video device for this channel */
> +	struct video_device video_dev;
> +	/* Pointer to the parent handle */
> +	struct unicam_device *dev;
> +	struct media_pad pad;
> +	/*
> +	 * Dummy buffer intended to be used by unicam
> +	 * if we have no other queued buffers to swap to.
> +	 */
> +	struct unicam_buffer dummy_buf;
> +	void *dummy_buf_cpu_addr;
> +};
> +
> +struct unicam_device {
> +	struct kref kref;
> +
> +	/* peripheral base address */
> +	void __iomem *base;
> +	/* clock gating base address */
> +	void __iomem *clk_gate_base;
> +	/* lp clock handle */
> +	struct clk *clock;
> +	/* vpu clock handle */
> +	struct clk *vpu_clock;
> +	/* V4l2 device */
> +	struct v4l2_device v4l2_dev;
> +	struct media_device mdev;
> +
> +	/* parent device */
> +	struct device *dev;
> +	/* subdevice async Notifier */
> +	struct v4l2_async_notifier notifier;
> +	unsigned int sequence;
> +
> +	/* Sensor node */
> +	struct {
> +		struct v4l2_subdev *subdev;
> +		struct media_pad *pad;
> +	} sensor;
> +
> +	/* Internal subdev */
> +	struct {
> +		struct v4l2_subdev sd;
> +		struct media_pad pads[UNICAM_SD_NUM_PADS];
> +		bool streaming;
> +	} subdev;
> +
> +	enum v4l2_mbus_type bus_type;
> +	/*
> +	 * Stores bus.mipi_csi2.flags for CSI2 sensors, or
> +	 * bus.mipi_csi1.strobe for CCP2.
> +	 */
> +	unsigned int bus_flags;
> +	unsigned int max_data_lanes;
> +	unsigned int active_data_lanes;
> +
> +	struct media_pipeline pipe;
> +
> +	struct unicam_node node[UNICAM_MAX_NODES];
> +};
> +
> +static inline struct unicam_device *
> +notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
> +{
> +	return container_of(notifier, struct unicam_device, notifier);
> +}
> +
> +static inline struct unicam_device *
> +sd_to_unicam_device(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct unicam_device, subdev.sd);
> +}
> +
> +static void unicam_release(struct kref *kref)
> +{
> +	struct unicam_device *unicam =
> +		container_of(kref, struct unicam_device, kref);
> +
> +	if (unicam->mdev.dev)
> +		media_device_cleanup(&unicam->mdev);
> +
> +	kfree(unicam);
> +}
> +
> +static struct unicam_device *unicam_get(struct unicam_device *unicam)
> +{
> +	kref_get(&unicam->kref);

A newline here would be nice.

> +	return unicam;
> +}
> +
> +static void unicam_put(struct unicam_device *unicam)
> +{
> +	kref_put(&unicam->kref, unicam_release);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Misc helper functions
> + */
> +
> +static inline bool unicam_sd_pad_is_source(u32 pad)
> +{
> +	/* Camera RX has 1 sink pad, and N source pads */
> +	return pad != UNICAM_SD_PAD_SINK;
> +}
> +
> +static inline bool is_metadata_node(struct unicam_node *node)
> +{
> +	return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
> +}
> +
> +static inline bool is_image_node(struct unicam_node *node)
> +{
> +	return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Format data table and helper functions
> + */
> +
> +static const struct v4l2_mbus_framefmt unicam_default_image_format = {
> +	.width = 640,
> +	.height = 480,
> +	.code = MEDIA_BUS_FMT_UYVY8_1X16,
> +	.field = V4L2_FIELD_NONE,
> +	.colorspace = V4L2_COLORSPACE_SRGB,
> +	.ycbcr_enc = V4L2_YCBCR_ENC_601,
> +	.quantization = V4L2_QUANTIZATION_LIM_RANGE,
> +	.xfer_func = V4L2_XFER_FUNC_SRGB,
> +	.flags = 0,
> +};
> +
> +static const struct v4l2_mbus_framefmt unicam_default_meta_format = {
> +	.width = 640,
> +	.height = 2,
> +	.code = MEDIA_BUS_FMT_META_8,
> +	.field = V4L2_FIELD_NONE,
> +};
> +
> +static const struct unicam_format_info unicam_image_formats[] = {
> +	/* YUV Formats */
> +	{
> +		.fourcc		= V4L2_PIX_FMT_YUYV,
> +		.code		= MEDIA_BUS_FMT_YUYV8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_UYVY,
> +		.code		= MEDIA_BUS_FMT_UYVY8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_YVYU,
> +		.code		= MEDIA_BUS_FMT_YVYU8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_VYUY,
> +		.code		= MEDIA_BUS_FMT_VYUY8_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x1e,
> +	}, {
> +	/* RGB Formats */
> +		.fourcc		= V4L2_PIX_FMT_RGB565, /* gggbbbbb rrrrrggg */
> +		.code		= MEDIA_BUS_FMT_RGB565_1X16,
> +		.depth		= 16,
> +		.csi_dt		= 0x22,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_RGB24, /* rgb */
> +		.code		= MEDIA_BUS_FMT_RGB888_1X24,
> +		.depth		= 24,
> +		.csi_dt		= 0x24,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_BGR24, /* bgr */
> +		.code		= MEDIA_BUS_FMT_BGR888_1X24,
> +		.depth		= 24,
> +		.csi_dt		= 0x24,
> +	}, {
> +	/* Bayer Formats */
> +		.fourcc		= V4L2_PIX_FMT_SBGGR8,
> +		.code		= MEDIA_BUS_FMT_SBGGR8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG8,
> +		.code		= MEDIA_BUS_FMT_SGBRG8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG8,
> +		.code		= MEDIA_BUS_FMT_SGRBG8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB8,
> +		.code		= MEDIA_BUS_FMT_SRGGB8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SBGGR10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR10,
> +		.code		= MEDIA_BUS_FMT_SBGGR10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG10,
> +		.code		= MEDIA_BUS_FMT_SGBRG10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG10,
> +		.code		= MEDIA_BUS_FMT_SGRBG10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB10,
> +		.code		= MEDIA_BUS_FMT_SRGGB10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SBGGR12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR12,
> +		.code		= MEDIA_BUS_FMT_SBGGR12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG12,
> +		.code		= MEDIA_BUS_FMT_SGBRG12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG12,
> +		.code		= MEDIA_BUS_FMT_SGRBG12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB12,
> +		.code		= MEDIA_BUS_FMT_SRGGB12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SBGGR14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR14,
> +		.code		= MEDIA_BUS_FMT_SBGGR14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGBRG14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG14,
> +		.code		= MEDIA_BUS_FMT_SGBRG14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SGRBG14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG14,
> +		.code		= MEDIA_BUS_FMT_SGRBG14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_SRGGB14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB14,
> +		.code		= MEDIA_BUS_FMT_SRGGB14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	}, {
> +	/* 16 bit Bayer formats could be supported. */
> +
> +	/* Greyscale formats */
> +		.fourcc		= V4L2_PIX_FMT_GREY,
> +		.code		= MEDIA_BUS_FMT_Y8_1X8,
> +		.depth		= 8,
> +		.csi_dt		= 0x2a,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_Y10P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_Y10,
> +		.code		= MEDIA_BUS_FMT_Y10_1X10,
> +		.depth		= 10,
> +		.csi_dt		= 0x2b,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_Y12P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_Y12,
> +		.code		= MEDIA_BUS_FMT_Y12_1X12,
> +		.depth		= 12,
> +		.csi_dt		= 0x2c,
> +	}, {
> +		.fourcc		= V4L2_PIX_FMT_Y14P,
> +		.unpacked_fourcc = V4L2_PIX_FMT_Y14,
> +		.code		= MEDIA_BUS_FMT_Y14_1X14,
> +		.depth		= 14,
> +		.csi_dt		= 0x2d,
> +	},
> +};
> +
> +static const struct unicam_format_info unicam_meta_formats[] = {
> +	{
> +		.fourcc		= V4L2_META_FMT_GENERIC_8,
> +		.code		= MEDIA_BUS_FMT_META_8,
> +		.depth		= 8,
> +		.metadata_fmt	= true,
> +	}, {
> +		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_10,
> +		.code		= MEDIA_BUS_FMT_META_10,
> +		.depth		= 10,
> +		.metadata_fmt	= true,
> +	}, {
> +		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_12,
> +		.code		= MEDIA_BUS_FMT_META_12,
> +		.depth		= 12,
> +		.metadata_fmt	= true,
> +	}, {
> +		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_14,
> +		.code		= MEDIA_BUS_FMT_META_14,
> +		.depth		= 14,
> +		.metadata_fmt	= true,
> +	},
> +};
> +
> +/* Format setup functions */
> +static const struct unicam_format_info *
> +unicam_find_format_by_code(u32 code, u32 pad)
> +{
> +	const struct unicam_format_info *formats;
> +	unsigned int num_formats;
> +	unsigned int i;
> +
> +	if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +		formats = unicam_image_formats;
> +		num_formats = ARRAY_SIZE(unicam_image_formats);
> +	} else {
> +		formats = unicam_meta_formats;
> +		num_formats = ARRAY_SIZE(unicam_meta_formats);
> +	}
> +
> +	for (i = 0; i < num_formats; i++) {
> +		if (formats[i].code == code)
> +			return &formats[i];
> +	}
> +
> +	return NULL;
> +}
> +
> +static const struct unicam_format_info *
> +unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
> +{
> +	const struct unicam_format_info *formats;
> +	unsigned int num_formats;
> +	unsigned int i;
> +
> +	if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +		formats = unicam_image_formats;
> +		num_formats = ARRAY_SIZE(unicam_image_formats);
> +	} else {
> +		formats = unicam_meta_formats;
> +		num_formats = ARRAY_SIZE(unicam_meta_formats);
> +	}
> +
> +	for (i = 0; i < num_formats; ++i) {
> +		if (formats[i].fourcc == fourcc)
> +			return &formats[i];
> +	}
> +
> +	return NULL;
> +}
> +
> +static void unicam_calc_image_size_bpl(struct unicam_device *unicam,
> +				       const struct unicam_format_info *fmtinfo,
> +				       struct v4l2_pix_format *pix)
> +{
> +	u32 min_bpl;
> +
> +	v4l_bound_align_image(&pix->width, UNICAM_IMAGE_MIN_WIDTH,
> +			      UNICAM_IMAGE_MAX_WIDTH, 2,
> +			      &pix->height, UNICAM_IMAGE_MIN_HEIGHT,
> +			      UNICAM_IMAGE_MAX_HEIGHT, 0, 0);
> +
> +	/* Unpacking always goes to 16bpp */
> +	if (pix->pixelformat == fmtinfo->unpacked_fourcc)
> +		min_bpl = pix->width * 2;
> +	else
> +		min_bpl = pix->width * fmtinfo->depth / 8;
> +	min_bpl = ALIGN(min_bpl, UNICAM_IMAGE_BPL_ALIGNMENT);
> +
> +	pix->bytesperline = ALIGN(pix->bytesperline, UNICAM_IMAGE_BPL_ALIGNMENT);
> +	pix->bytesperline = clamp_t(unsigned int, pix->bytesperline, min_bpl,
> +				    UNICAM_IMAGE_MAX_BPL);
> +
> +	pix->sizeimage = pix->height * pix->bytesperline;
> +}
> +
> +static void unicam_calc_meta_size_bpl(struct unicam_device *unicam,
> +				      const struct unicam_format_info *fmtinfo,
> +				      struct v4l2_meta_format *meta)
> +{
> +	v4l_bound_align_image(&meta->width, UNICAM_META_MIN_WIDTH,
> +			      UNICAM_META_MAX_WIDTH, 0,
> +			      &meta->height, UNICAM_META_MIN_HEIGHT,
> +			      UNICAM_META_MAX_HEIGHT, 0, 0);
> +
> +	meta->bytesperline = ALIGN(meta->width * fmtinfo->depth / 8,
> +				   UNICAM_DMA_BPL_ALIGNMENT);
> +	meta->buffersize = meta->height * meta->bytesperline;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Hardware handling
> + */
> +
> +static inline void unicam_clk_write(struct unicam_device *unicam, u32 val)
> +{
> +	/* Pass the CM_PASSWORD along with the value. */
> +	writel(val | 0x5a000000, unicam->clk_gate_base);
> +}
> +
> +static inline u32 unicam_reg_read(struct unicam_device *unicam, u32 offset)
> +{
> +	return readl(unicam->base + offset);
> +}
> +
> +static inline void unicam_reg_write(struct unicam_device *unicam, u32 offset, u32 val)
> +{
> +	writel(val, unicam->base + offset);
> +}
> +
> +static inline int unicam_get_field(u32 value, u32 mask)
> +{
> +	return (value & mask) >> __ffs(mask);
> +}
> +
> +static inline void unicam_set_field(u32 *valp, u32 field, u32 mask)
> +{
> +	u32 val = *valp;
> +
> +	val &= ~mask;
> +	val |= (field << __ffs(mask)) & mask;
> +	*valp = val;
> +}
> +
> +static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offset,
> +					  u32 field, u32 mask)
> +{
> +	u32 val = unicam_reg_read(unicam, offset);
> +
> +	unicam_set_field(&val, field, mask);
> +	unicam_reg_write(unicam, offset, val);
> +}
> +
> +static void unicam_wr_dma_addr(struct unicam_node *node,
> +			       struct unicam_buffer *buf)
> +{
> +	dma_addr_t endaddr = buf->dma_addr + buf->size;
> +
> +	if (node->id == UNICAM_IMAGE_NODE) {
> +		unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
> +		unicam_reg_write(node->dev, UNICAM_IBEA0, endaddr);
> +	} else {
> +		unicam_reg_write(node->dev, UNICAM_DBSA0, buf->dma_addr);
> +		unicam_reg_write(node->dev, UNICAM_DBEA0, endaddr);
> +	}
> +}
> +
> +static unsigned int unicam_get_lines_done(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +	unsigned int stride = node->fmt.fmt.pix.bytesperline;
> +	struct unicam_buffer *frm = node->cur_frm;
> +	dma_addr_t cur_addr;
> +
> +	if (!frm)
> +		return 0;
> +
> +	cur_addr = unicam_reg_read(unicam, UNICAM_IBWP);
> +	return (unsigned int)(cur_addr - frm->dma_addr) / stride;
> +}
> +
> +static void unicam_schedule_next_buffer(struct unicam_node *node)
> +{
> +	struct unicam_buffer *buf;
> +
> +	buf = list_first_entry(&node->dma_queue, struct unicam_buffer, list);
> +	node->next_frm = buf;
> +	list_del(&buf->list);
> +
> +	unicam_wr_dma_addr(node, buf);
> +}
> +
> +static void unicam_schedule_dummy_buffer(struct unicam_node *node)
> +{
> +	int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
> +
> +	dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
> +
> +	unicam_wr_dma_addr(node, &node->dummy_buf);
> +
> +	node->next_frm = NULL;
> +}
> +
> +static void unicam_process_buffer_complete(struct unicam_node *node,
> +					   unsigned int sequence)
> +{
> +	node->cur_frm->vb.field = node->fmt.fmt.pix.field;
> +	node->cur_frm->vb.sequence = sequence;
> +
> +	vb2_buffer_done(&node->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
> +}
> +
> +static void unicam_queue_event_sof(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +

Extra newline.

> +	struct v4l2_event event = {
> +		.type = V4L2_EVENT_FRAME_SYNC,
> +		.u.frame_sync.frame_sequence = unicam->sequence,
> +	};
> +
> +	v4l2_event_queue(&node->video_dev, &event);
> +}
> +
> +static irqreturn_t unicam_isr(int irq, void *dev)
> +{
> +	struct unicam_device *unicam = dev;
> +	unsigned int lines_done = unicam_get_lines_done(dev);
> +	unsigned int sequence = unicam->sequence;
> +	unsigned int i;
> +	u32 ista, sta;
> +	bool fe;
> +	u64 ts;
> +
> +	sta = unicam_reg_read(unicam, UNICAM_STA);
> +	/* Write value back to clear the interrupts */
> +	unicam_reg_write(unicam, UNICAM_STA, sta);
> +
> +	ista = unicam_reg_read(unicam, UNICAM_ISTA);
> +	/* Write value back to clear the interrupts */
> +	unicam_reg_write(unicam, UNICAM_ISTA, ista);
> +
> +	dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> +		ista, sta, sequence, lines_done);
> +
> +	if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> +		return IRQ_HANDLED;
> +
> +	/*
> +	 * Look for either the Frame End interrupt or the Packet Capture status
> +	 * to signal a frame end.
> +	 */
> +	fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> +
> +	/*
> +	 * We must run the frame end handler first. If we have a valid next_frm
> +	 * and we get a simultaneout FE + FS interrupt, running the FS handler
> +	 * first would null out the next_frm ptr and we would have lost the
> +	 * buffer forever.
> +	 */
> +	if (fe) {
> +		/*
> +		 * Ensure we have swapped buffers already as we can't
> +		 * stop the peripheral. If no buffer is available, use a
> +		 * dummy buffer to dump out frames until we get a new buffer
> +		 * to use.
> +		 */
> +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +			if (!unicam->node[i].streaming)
> +				continue;
> +
> +			/*
> +			 * If cur_frm == next_frm, it means we have not had
> +			 * a chance to swap buffers, likely due to having
> +			 * multiple interrupts occurring simultaneously (like FE
> +			 * + FS + LS). In this case, we cannot signal the buffer
> +			 * as complete, as the HW will reuse that buffer.
> +			 */
> +			if (unicam->node[i].cur_frm &&
> +			    unicam->node[i].cur_frm != unicam->node[i].next_frm)
> +				unicam_process_buffer_complete(&unicam->node[i],
> +							       sequence);
> +			unicam->node[i].cur_frm = unicam->node[i].next_frm;
> +		}
> +		unicam->sequence++;

Does access to this data need to be serialised somehow.

> +	}
> +
> +	if (ista & UNICAM_FSI) {
> +		/*
> +		 * Timestamp is to be when the first data byte was captured,
> +		 * aka frame start.
> +		 */
> +		ts = ktime_get_ns();
> +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +			if (!unicam->node[i].streaming)
> +				continue;
> +
> +			if (unicam->node[i].cur_frm)
> +				unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> +								ts;
> +			else
> +				dev_dbg(unicam->v4l2_dev.dev,
> +					"ISR: [%d] Dropping frame, buffer not available at FS\n",
> +					i);
> +			/*
> +			 * Set the next frame output to go to a dummy frame
> +			 * if we have not managed to obtain another frame
> +			 * from the queue.
> +			 */
> +			unicam_schedule_dummy_buffer(&unicam->node[i]);
> +		}
> +
> +		unicam_queue_event_sof(unicam);
> +	}
> +
> +	/*
> +	 * Cannot swap buffer at frame end, there may be a race condition
> +	 * where the HW does not actually swap it if the new frame has
> +	 * already started.
> +	 */
> +	if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +			if (!unicam->node[i].streaming)
> +				continue;
> +
> +			spin_lock(&unicam->node[i].dma_queue_lock);
> +			if (!list_empty(&unicam->node[i].dma_queue) &&
> +			    !unicam->node[i].next_frm)
> +				unicam_schedule_next_buffer(&unicam->node[i]);
> +			spin_unlock(&unicam->node[i].dma_queue_lock);
> +		}
> +	}
> +
> +	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> +		/* Switch out of trigger mode if selected */
> +		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> +		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> +	}
> +	return IRQ_HANDLED;
> +}
> +
> +static void unicam_set_packing_config(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +	u32 pack, unpack;
> +	u32 val;
> +
> +	if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> +		unpack = UNICAM_PUM_NONE;
> +		pack = UNICAM_PPM_NONE;
> +	} else {
> +		switch (node->fmtinfo->depth) {
> +		case 8:
> +			unpack = UNICAM_PUM_UNPACK8;
> +			break;
> +		case 10:
> +			unpack = UNICAM_PUM_UNPACK10;
> +			break;
> +		case 12:
> +			unpack = UNICAM_PUM_UNPACK12;
> +			break;
> +		case 14:
> +			unpack = UNICAM_PUM_UNPACK14;
> +			break;
> +		case 16:
> +			unpack = UNICAM_PUM_UNPACK16;
> +			break;
> +		default:
> +			unpack = UNICAM_PUM_NONE;
> +			break;
> +		}
> +
> +		/* Repacking is always to 16bpp */
> +		pack = UNICAM_PPM_PACK16;

Also 8-bit data?

> +	}
> +
> +	val = 0;

You could do initialisation in declaration.

> +	unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> +	unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> +	unicam_reg_write(unicam, UNICAM_IPIPE, val);
> +}
> +
> +static void unicam_cfg_image_id(struct unicam_device *unicam)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		/* CSI2 mode, hardcode VC 0 for now. */
> +		unicam_reg_write(unicam, UNICAM_IDI0,
> +				 (0 << 6) | node->fmtinfo->csi_dt);
> +	} else {
> +		/* CCP2 mode */
> +		unicam_reg_write(unicam, UNICAM_IDI0,
> +				 0x80 | node->fmtinfo->csi_dt);
> +	}
> +}
> +
> +static void unicam_enable_ed(struct unicam_device *unicam)
> +{
> +	u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> +
> +	unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> +	/* Do not wrap at the end of the embedded data buffer */
> +	unicam_set_field(&val, 0, UNICAM_DBOB);
> +
> +	unicam_reg_write(unicam, UNICAM_DCS, val);
> +}
> +
> +static void unicam_start_rx(struct unicam_device *unicam,
> +			    struct unicam_buffer *buf)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> +	int line_int_freq = node->fmt.fmt.pix.height >> 2;
> +	unsigned int i;
> +	u32 val;
> +
> +	if (line_int_freq < 128)
> +		line_int_freq = 128;

	line_int_freq = max(line_int_freq, 128);

> +
> +	/* Enable lane clocks */
> +	val = 1;

Initialise in the loop initialisation below, I'd say.

> +	for (i = 0; i < unicam->active_data_lanes; i++)
> +		val = val << 2 | 1;
> +	unicam_clk_write(unicam, val);
> +
> +	/* Basic init */
> +	unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> +
> +	/* Enable analogue control, and leave in reset. */
> +	val = UNICAM_AR;
> +	unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> +	unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> +	unicam_reg_write(unicam, UNICAM_ANA, val);
> +	usleep_range(1000, 2000);
> +
> +	/* Come out of reset */
> +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> +
> +	/* Peripheral reset */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> +
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> +
> +	/* Enable Rx control. */
> +	val = unicam_reg_read(unicam, UNICAM_CTRL);
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> +		unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> +	} else {
> +		unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> +		unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> +	}
> +	/* Packet framer timeout */
> +	unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> +	unicam_set_field(&val, 128, UNICAM_OET_MASK);
> +	unicam_reg_write(unicam, UNICAM_CTRL, val);
> +
> +	unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> +	unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> +
> +	/* AXI bus access QoS setup */
> +	val = unicam_reg_read(unicam, UNICAM_PRI);
> +	unicam_set_field(&val, 0, UNICAM_BL_MASK);
> +	unicam_set_field(&val, 0, UNICAM_BS_MASK);
> +	unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> +	unicam_set_field(&val, 8, UNICAM_NP_MASK);
> +	unicam_set_field(&val, 2, UNICAM_PT_MASK);
> +	unicam_set_field(&val, 1, UNICAM_PE);
> +	unicam_reg_write(unicam, UNICAM_PRI, val);
> +
> +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> +
> +	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
> +	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> +	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> +	unicam_reg_write(unicam, UNICAM_ICTL, val);
> +	unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> +	unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> +
> +	/* tclk_term_en */
> +	unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> +	/* tclk_settle */
> +	unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> +	/* td_term_en */
> +	unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> +	/* ths_settle */
> +	unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> +	/* trx_enable */
> +	unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> +
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> +
> +	/* Packet compare setup - required to avoid missing frame ends */
> +	val = 0;
> +	unicam_set_field(&val, 1, UNICAM_PCE);
> +	unicam_set_field(&val, 1, UNICAM_GI);
> +	unicam_set_field(&val, 1, UNICAM_CPH);
> +	unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> +	unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> +	unicam_reg_write(unicam, UNICAM_CMP0, val);
> +
> +	/* Enable clock lane and set up terminations */
> +	val = 0;
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		/* CSI2 */
> +		unicam_set_field(&val, 1, UNICAM_CLE);
> +		unicam_set_field(&val, 1, UNICAM_CLLPE);
> +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> +			unicam_set_field(&val, 1, UNICAM_CLTRE);
> +			unicam_set_field(&val, 1, UNICAM_CLHSE);
> +		}
> +	} else {
> +		/* CCP2 */
> +		unicam_set_field(&val, 1, UNICAM_CLE);
> +		unicam_set_field(&val, 1, UNICAM_CLHSE);
> +		unicam_set_field(&val, 1, UNICAM_CLTRE);
> +	}
> +	unicam_reg_write(unicam, UNICAM_CLK, val);
> +
> +	/*
> +	 * Enable required data lanes with appropriate terminations.
> +	 * The same value needs to be written to UNICAM_DATn registers for
> +	 * the active lanes, and 0 for inactive ones.
> +	 */
> +	val = 0;
> +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> +		/* CSI2 */
> +		unicam_set_field(&val, 1, UNICAM_DLE);
> +		unicam_set_field(&val, 1, UNICAM_DLLPE);
> +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> +			unicam_set_field(&val, 1, UNICAM_DLTRE);
> +			unicam_set_field(&val, 1, UNICAM_DLHSE);
> +		}
> +	} else {
> +		/* CCP2 */
> +		unicam_set_field(&val, 1, UNICAM_DLE);
> +		unicam_set_field(&val, 1, UNICAM_DLHSE);
> +		unicam_set_field(&val, 1, UNICAM_DLTRE);
> +	}
> +	unicam_reg_write(unicam, UNICAM_DAT0, val);
> +
> +	if (unicam->active_data_lanes == 1)
> +		val = 0;
> +	unicam_reg_write(unicam, UNICAM_DAT1, val);
> +
> +	if (unicam->max_data_lanes > 2) {
> +		/*
> +		 * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> +		 * instance supports more than 2 data lanes.
> +		 */
> +		if (unicam->active_data_lanes == 2)
> +			val = 0;
> +		unicam_reg_write(unicam, UNICAM_DAT2, val);
> +
> +		if (unicam->active_data_lanes == 3)
> +			val = 0;
> +		unicam_reg_write(unicam, UNICAM_DAT3, val);
> +	}
> +
> +	unicam_reg_write(unicam, UNICAM_IBLS,
> +			 node->fmt.fmt.pix.bytesperline);
> +	unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> +	unicam_set_packing_config(unicam);
> +	unicam_cfg_image_id(unicam);
> +
> +	val = unicam_reg_read(unicam, UNICAM_MISC);
> +	unicam_set_field(&val, 1, UNICAM_FL0);
> +	unicam_set_field(&val, 1, UNICAM_FL1);
> +	unicam_reg_write(unicam, UNICAM_MISC, val);
> +
> +	/* Enable peripheral */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> +
> +	/* Load image pointers */
> +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> +
> +	/*
> +	 * Enable trigger only for the first frame to
> +	 * sync correctly to the FS from the source.
> +	 */
> +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> +}
> +
> +static void unicam_start_metadata(struct unicam_device *unicam,
> +				  struct unicam_buffer *buf)
> +{
> +	struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
> +
> +	unicam_enable_ed(unicam);
> +	unicam_wr_dma_addr(node, buf);
> +	unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
> +}
> +
> +static void unicam_disable(struct unicam_device *unicam)
> +{
> +	/* Analogue lane control disable */
> +	unicam_reg_write_field(unicam, UNICAM_ANA, 1, UNICAM_DDL);
> +
> +	/* Stop the output engine */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_SOE);
> +
> +	/* Disable the data lanes. */
> +	unicam_reg_write(unicam, UNICAM_DAT0, 0);
> +	unicam_reg_write(unicam, UNICAM_DAT1, 0);
> +
> +	if (unicam->max_data_lanes > 2) {
> +		unicam_reg_write(unicam, UNICAM_DAT2, 0);
> +		unicam_reg_write(unicam, UNICAM_DAT3, 0);
> +	}
> +
> +	/* Peripheral reset */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> +	usleep_range(50, 100);
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> +
> +	/* Disable peripheral */
> +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> +
> +	/* Clear ED setup */
> +	unicam_reg_write(unicam, UNICAM_DCS, 0);
> +
> +	/* Disable all lane clocks */
> +	unicam_clk_write(unicam, 0);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * V4L2 subdev operations
> + */
> +
> +static int __unicam_subdev_set_routing(struct v4l2_subdev *sd,
> +				       struct v4l2_subdev_state *state,
> +				       struct v4l2_subdev_krouting *routing)
> +{
> +	struct v4l2_subdev_route *route;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_validate(sd, routing,
> +					   V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_subdev_set_routing(sd, state, routing);
> +	if (ret)
> +		return ret;
> +
> +	for_each_active_route(&state->routing, route) {
> +		const struct v4l2_mbus_framefmt *def_fmt;
> +		struct v4l2_mbus_framefmt *fmt;
> +
> +		if (route->source_pad == UNICAM_SD_PAD_SOURCE_IMAGE)
> +			def_fmt = &unicam_default_image_format;
> +		else
> +			def_fmt = &unicam_default_meta_format;
> +
> +		fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
> +						   route->sink_stream);
> +		*fmt = *def_fmt;
> +		fmt = v4l2_subdev_state_get_format(state, route->source_pad,
> +						   route->source_stream);
> +		*fmt = *def_fmt;
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_init_state(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state)
> +{
> +	struct v4l2_subdev_route routes[] = {
> +		{
> +			.sink_pad = UNICAM_SD_PAD_SINK,
> +			.sink_stream = 0,
> +			.source_pad = UNICAM_SD_PAD_SOURCE_IMAGE,
> +			.source_stream = 0,
> +			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
> +		},
> +	};
> +
> +	struct v4l2_subdev_krouting routing = {
> +		.len_routes = ARRAY_SIZE(routes),
> +		.num_routes = ARRAY_SIZE(routes),
> +		.routes = routes,
> +	};
> +
> +	/* Initialize routing to single route to the fist source pad. */
> +	return __unicam_subdev_set_routing(sd, state, &routing);
> +}
> +
> +static int unicam_subdev_enum_mbus_code(struct v4l2_subdev *sd,
> +					struct v4l2_subdev_state *state,
> +					struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	u32 pad, stream;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +						    code->pad, code->stream,
> +						    &pad, &stream);
> +	if (ret)
> +		return ret;
> +
> +	if (unicam_sd_pad_is_source(code->pad)) {
> +		/* No transcoding, source and sink codes must match. */
> +		const struct v4l2_mbus_framefmt *fmt;
> +
> +		fmt = v4l2_subdev_state_get_format(state, pad, stream);
> +		if (!fmt)
> +			return -EINVAL;
> +
> +		if (code->index > 0)
> +			return -EINVAL;
> +
> +		code->code = fmt->code;
> +	} else {
> +		const struct unicam_format_info *formats;
> +		unsigned int num_formats;
> +
> +		if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +			formats = unicam_image_formats;
> +			num_formats = ARRAY_SIZE(unicam_image_formats);
> +		} else {
> +			formats = unicam_meta_formats;
> +			num_formats = ARRAY_SIZE(unicam_meta_formats);
> +		}
> +
> +		if (code->index >= num_formats)
> +			return -EINVAL;
> +
> +		code->code = formats[code->index].code;
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_enum_frame_size(struct v4l2_subdev *sd,
> +					 struct v4l2_subdev_state *state,
> +					 struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	u32 pad, stream;
> +	int ret;
> +
> +	if (fse->index > 0)
> +		return -EINVAL;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, fse->pad,
> +						    fse->stream, &pad,
> +						    &stream);
> +	if (ret)
> +		return ret;
> +
> +	if (unicam_sd_pad_is_source(fse->pad)) {
> +		/* No transcoding, source and sink formats must match. */
> +		const struct v4l2_mbus_framefmt *fmt;
> +
> +		fmt = v4l2_subdev_state_get_format(state, pad, stream);
> +		if (!fmt)
> +			return -EINVAL;
> +
> +		if (fse->code != fmt->code)
> +			return -EINVAL;
> +
> +		fse->min_width = fmt->width;
> +		fse->max_width = fmt->width;
> +		fse->min_height = fmt->height;
> +		fse->max_height = fmt->height;
> +	} else {
> +		const struct unicam_format_info *fmtinfo;
> +
> +		fmtinfo = unicam_find_format_by_code(fse->code, pad);
> +		if (!fmtinfo)
> +			return -EINVAL;
> +
> +		if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +			fse->min_width = UNICAM_IMAGE_MIN_WIDTH;
> +			fse->max_width = UNICAM_IMAGE_MAX_WIDTH;
> +			fse->min_height = UNICAM_IMAGE_MIN_HEIGHT;
> +			fse->max_height = UNICAM_IMAGE_MAX_HEIGHT;
> +		} else {
> +			fse->min_width = UNICAM_META_MIN_WIDTH;
> +			fse->max_width = UNICAM_META_MAX_WIDTH;
> +			fse->min_height = UNICAM_META_MIN_HEIGHT;
> +			fse->max_height = UNICAM_META_MAX_HEIGHT;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_set_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +	struct v4l2_mbus_framefmt *sink_format, *source_format;
> +	const struct unicam_format_info *fmtinfo;
> +	u32 source_pad, source_stream;
> +	int ret;
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
> +	    unicam->subdev.streaming)
> +		return -EBUSY;
> +
> +	/* No transcoding, source and sink formats must match. */
> +	if (unicam_sd_pad_is_source(format->pad))
> +		return v4l2_subdev_get_fmt(sd, state, format);
> +
> +	/*
> +	 * Allowed formats for the stream on the sink pad depend on what source
> +	 * pad the stream is routed to. Find the corresponding source pad and
> +	 * use it to validate the media bus code.
> +	 */
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +						    format->pad, format->stream,
> +						    &source_pad, &source_stream);
> +	if (ret)
> +		return ret;
> +
> +	fmtinfo = unicam_find_format_by_code(format->format.code, source_pad);
> +	if (!fmtinfo) {
> +		fmtinfo = source_pad == UNICAM_SD_PAD_SOURCE_IMAGE
> +			? &unicam_image_formats[0] : &unicam_meta_formats[0];
> +		format->format.code = fmtinfo->code;
> +	}
> +
> +	if (source_pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
> +		format->format.width = clamp_t(unsigned int,
> +					       format->format.width,
> +					       UNICAM_IMAGE_MIN_WIDTH,
> +					       UNICAM_IMAGE_MAX_WIDTH);
> +		format->format.height = clamp_t(unsigned int,
> +						format->format.height,
> +						UNICAM_IMAGE_MIN_HEIGHT,
> +						UNICAM_IMAGE_MAX_HEIGHT);
> +		format->format.field = V4L2_FIELD_NONE;
> +	} else {
> +		format->format.width = clamp_t(unsigned int,
> +					       format->format.width,
> +					       UNICAM_META_MIN_WIDTH,
> +					       UNICAM_META_MAX_WIDTH);
> +		format->format.height = clamp_t(unsigned int,
> +						format->format.height,
> +						UNICAM_META_MIN_HEIGHT,
> +						UNICAM_META_MAX_HEIGHT);
> +		format->format.field = V4L2_FIELD_NONE;
> +
> +		/* Colorspace don't apply to metadata. */
> +		format->format.colorspace = 0;
> +		format->format.ycbcr_enc = 0;
> +		format->format.quantization = 0;
> +		format->format.xfer_func = 0;
> +	}
> +
> +	sink_format = v4l2_subdev_state_get_format(state, format->pad,
> +						   format->stream);
> +	source_format = v4l2_subdev_state_get_format(state, source_pad,
> +						     source_stream);
> +	*sink_format = format->format;
> +	*source_format = format->format;
> +
> +	return 0;
> +}
> +
> +static int unicam_subdev_set_routing(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *state,
> +				     enum v4l2_subdev_format_whence which,
> +				     struct v4l2_subdev_krouting *routing)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +
> +	if (which == V4L2_SUBDEV_FORMAT_ACTIVE && unicam->subdev.streaming)
> +		return -EBUSY;
> +
> +	return __unicam_subdev_set_routing(sd, state, routing);
> +}
> +
> +static int unicam_sd_enable_streams(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state, u32 pad,
> +				    u64 streams_mask)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +	u32 other_pad, other_stream;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> +						    &other_pad, &other_stream);
> +	if (ret)
> +		return ret;
> +
> +	unicam->sequence = 0;
> +
> +	ret = v4l2_subdev_enable_streams(unicam->sensor.subdev,
> +					 unicam->sensor.pad->index,
> +					 BIT(other_stream));
> +	if (ret) {
> +		dev_err(unicam->dev, "stream on failed in subdev\n");
> +		return ret;
> +	}
> +
> +	unicam->subdev.streaming = true;
> +
> +	return 0;
> +}
> +
> +static int unicam_sd_disable_streams(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *state, u32 pad,
> +				     u64 streams_mask)
> +{
> +	struct unicam_device *unicam = sd_to_unicam_device(sd);
> +	u32 other_pad, other_stream;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
> +						    &other_pad, &other_stream);
> +	if (ret)
> +		return ret;
> +
> +	v4l2_subdev_disable_streams(unicam->sensor.subdev,
> +				    unicam->sensor.pad->index,
> +				    BIT(other_stream));
> +
> +	unicam->subdev.streaming = false;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_pad_ops unicam_subdev_pad_ops = {
> +	.enum_mbus_code		= unicam_subdev_enum_mbus_code,
> +	.enum_frame_size	= unicam_subdev_enum_frame_size,
> +	.get_fmt		= v4l2_subdev_get_fmt,
> +	.set_fmt		= unicam_subdev_set_format,
> +	.set_routing		= unicam_subdev_set_routing,
> +	.enable_streams		= unicam_sd_enable_streams,
> +	.disable_streams	= unicam_sd_disable_streams,
> +};
> +
> +static const struct v4l2_subdev_ops unicam_subdev_ops = {
> +	.pad			= &unicam_subdev_pad_ops,
> +};
> +
> +static const struct v4l2_subdev_internal_ops unicam_subdev_internal_ops = {
> +	.init_state		= unicam_subdev_init_state,
> +};
> +
> +static const struct media_entity_operations unicam_subdev_media_ops = {
> +	.link_validate		= v4l2_subdev_link_validate,
> +	.has_pad_interdep	= v4l2_subdev_has_pad_interdep,
> +};
> +
> +static int unicam_subdev_init(struct unicam_device *unicam)
> +{
> +	struct v4l2_subdev *sd = &unicam->subdev.sd;
> +	int ret;
> +
> +	v4l2_subdev_init(sd, &unicam_subdev_ops);
> +	sd->internal_ops = &unicam_subdev_internal_ops;
> +	v4l2_set_subdevdata(sd, unicam);
> +
> +	sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> +	sd->entity.ops = &unicam_subdev_media_ops;
> +	sd->dev = unicam->dev;
> +	sd->owner = THIS_MODULE;
> +	sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
> +
> +	strscpy(sd->name, "unicam", sizeof(sd->name));
> +
> +	unicam->subdev.pads[UNICAM_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> +	unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_IMAGE].flags = MEDIA_PAD_FL_SOURCE;
> +	unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_METADATA].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(unicam->subdev.pads),
> +				     unicam->subdev.pads);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to initialize media entity: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	ret = v4l2_subdev_init_finalize(sd);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to initialize subdev: %d\n", ret);
> +		goto err_entity;
> +	}
> +
> +	ret = v4l2_device_register_subdev(&unicam->v4l2_dev, sd);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to register subdev: %d\n", ret);
> +		goto err_subdev;
> +	}
> +
> +	return 0;
> +
> +err_subdev:
> +	v4l2_subdev_cleanup(sd);
> +err_entity:
> +	media_entity_cleanup(&sd->entity);
> +	return ret;
> +}
> +
> +static void unicam_subdev_cleanup(struct unicam_device *unicam)
> +{
> +	v4l2_subdev_cleanup(&unicam->subdev.sd);
> +	media_entity_cleanup(&unicam->subdev.sd.entity);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Videobuf2 queue operations
> + */
> +
> +static int unicam_queue_setup(struct vb2_queue *vq,
> +			      unsigned int *nbuffers,
> +			      unsigned int *nplanes,
> +			      unsigned int sizes[],
> +			      struct device *alloc_devs[])
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vq);
> +	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> +		 : node->fmt.fmt.meta.buffersize;
> +
> +	if (vq->num_buffers + *nbuffers < 3)
> +		*nbuffers = 3 - vq->num_buffers;
> +
> +	if (*nplanes) {
> +		if (sizes[0] < size) {
> +			dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
> +				sizes[0], size);
> +			return -EINVAL;
> +		}
> +		size = sizes[0];
> +	}
> +
> +	*nplanes = 1;
> +	sizes[0] = size;
> +
> +	return 0;
> +}
> +
> +static int unicam_buffer_prepare(struct vb2_buffer *vb)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> +	struct unicam_buffer *buf = to_unicam_buffer(vb);
> +	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
> +		 : node->fmt.fmt.meta.buffersize;
> +
> +	if (vb2_plane_size(vb, 0) < size) {
> +		dev_dbg(node->dev->dev,
> +			"data will not fit into plane (%lu < %u)\n",
> +			vb2_plane_size(vb, 0), size);
> +		return -EINVAL;
> +	}
> +
> +	buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
> +	buf->size = size;
> +
> +	vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
> +
> +	return 0;
> +}
> +
> +static void unicam_return_buffers(struct unicam_node *node,
> +				  enum vb2_buffer_state state)
> +{
> +	struct unicam_buffer *buf, *tmp;
> +
> +	list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
> +		list_del(&buf->list);
> +		vb2_buffer_done(&buf->vb.vb2_buf, state);
> +	}
> +
> +	if (node->cur_frm)
> +		vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
> +				state);
> +	if (node->next_frm && node->cur_frm != node->next_frm)
> +		vb2_buffer_done(&node->next_frm->vb.vb2_buf,
> +				state);
> +
> +	node->cur_frm = NULL;
> +	node->next_frm = NULL;
> +}
> +
> +static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vq);
> +	struct unicam_device *unicam = node->dev;
> +	struct v4l2_subdev_state *state;
> +	struct unicam_buffer *buf;
> +	unsigned long flags;
> +	int ret;
> +	u32 pad, stream;
> +	u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +					     : UNICAM_SD_PAD_SOURCE_METADATA;
> +
> +	/* Look for the route for the given pad and stream. */
> +	state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
> +	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
> +						    remote_pad, 0,
> +						    &pad, &stream);
> +	v4l2_subdev_unlock_state(state);
> +
> +	if (ret)
> +		goto err_return_buffers;
> +
> +	dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
> +		unicam->subdev.sd.name, pad, stream, remote_pad, 0,
> +		is_metadata_node(node) ? "metadata" : "image");
> +
> +	/* The metadata node can't be started alone. */
> +	if (is_metadata_node(node)) {
> +		if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
> +			dev_err(unicam->dev,
> +				"Can't start metadata without image\n");
> +			ret = -EINVAL;
> +			goto err_return_buffers;
> +		}
> +
> +		spin_lock_irqsave(&node->dma_queue_lock, flags);
> +		buf = list_first_entry(&node->dma_queue,
> +				       struct unicam_buffer, list);
> +		dev_dbg(unicam->dev, "buffer %p\n", buf);
> +		node->cur_frm = buf;
> +		node->next_frm = buf;
> +		list_del(&buf->list);
> +		spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> +
> +		unicam_start_metadata(unicam, buf);
> +		node->streaming = true;
> +		return 0;
> +	}
> +
> +	ret = pm_runtime_resume_and_get(unicam->dev);
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
> +		goto err_return_buffers;
> +	}
> +
> +	ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
> +	if (ret < 0) {
> +		dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
> +		goto err_pm_put;
> +	}
> +
> +	spin_lock_irqsave(&node->dma_queue_lock, flags);
> +	buf = list_first_entry(&node->dma_queue,
> +			       struct unicam_buffer, list);
> +	dev_dbg(unicam->dev, "buffer %p\n", buf);
> +	node->cur_frm = buf;
> +	node->next_frm = buf;
> +	list_del(&buf->list);
> +	spin_unlock_irqrestore(&node->dma_queue_lock, flags);
> +
> +	unicam_start_rx(unicam, buf);
> +
> +	ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "stream on failed in subdev\n");
> +		goto error_pipeline;
> +	}
> +
> +	node->streaming = true;
> +
> +	return 0;
> +
> +error_pipeline:
> +	video_device_pipeline_stop(&node->video_dev);
> +err_pm_put:
> +	pm_runtime_put_sync(unicam->dev);
> +err_return_buffers:
> +	unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
> +	return ret;
> +}
> +
> +static void unicam_stop_streaming(struct vb2_queue *vq)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vq);
> +	struct unicam_device *unicam = node->dev;
> +	u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +						   : UNICAM_SD_PAD_SOURCE_METADATA;
> +
> +	node->streaming = false;
> +
> +	v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
> +				    BIT(0));
> +
> +	/* We can stream only with the image node. */
> +	if (is_metadata_node(node)) {
> +		/*
> +		 * Allow the hardware to spin in the dummy buffer.
> +		 * This is only really needed if the embedded data pad is
> +		 * disabled before the image pad.
> +		 */
> +		unicam_wr_dma_addr(node, &node->dummy_buf);
> +		goto dequeue_buffers;
> +	}
> +
> +	unicam_disable(unicam);
> +
> +	video_device_pipeline_stop(&node->video_dev);
> +	pm_runtime_put(unicam->dev);
> +
> +dequeue_buffers:
> +	/* Clear all queued buffers for the node */
> +	unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
> +}
> +
> +static void unicam_buffer_queue(struct vb2_buffer *vb)
> +{
> +	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
> +	struct unicam_buffer *buf = to_unicam_buffer(vb);
> +
> +	spin_lock_irq(&node->dma_queue_lock);
> +	list_add_tail(&buf->list, &node->dma_queue);
> +	spin_unlock_irq(&node->dma_queue_lock);
> +}
> +
> +static const struct vb2_ops unicam_video_qops = {
> +	.queue_setup		= unicam_queue_setup,
> +	.wait_prepare		= vb2_ops_wait_prepare,
> +	.wait_finish		= vb2_ops_wait_finish,
> +	.buf_prepare		= unicam_buffer_prepare,
> +	.start_streaming	= unicam_start_streaming,
> +	.stop_streaming		= unicam_stop_streaming,
> +	.buf_queue		= unicam_buffer_queue,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + *  V4L2 video device operations
> + */
> +
> +static int unicam_querycap(struct file *file, void *priv,
> +			   struct v4l2_capability *cap)
> +{
> +	strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
> +	strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
> +
> +	cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
> +
> +	return 0;
> +}
> +
> +static int unicam_enum_fmt_vid(struct file *file, void  *priv,
> +			       struct v4l2_fmtdesc *f)
> +{
> +	unsigned int index;
> +	unsigned int i;
> +
> +	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
> +		if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
> +			continue;
> +
> +		if (index == f->index) {
> +			f->pixelformat = unicam_image_formats[i].fourcc;
> +			return 0;
> +		}
> +
> +		index++;
> +
> +		if (!unicam_image_formats[i].unpacked_fourcc)
> +			continue;
> +
> +		if (index == f->index) {
> +			f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
> +			return 0;
> +		}
> +
> +		index++;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int unicam_g_fmt_vid(struct file *file, void *priv,
> +			    struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	*f = node->fmt;
> +
> +	return 0;
> +}
> +
> +static const struct unicam_format_info *
> +__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
> +{
> +	const struct unicam_format_info *fmtinfo;
> +
> +	/*
> +	 * Default to the first format if the requested pixel format code isn't
> +	 * supported.
> +	 */
> +	fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
> +					       UNICAM_SD_PAD_SOURCE_IMAGE);
> +	if (!fmtinfo) {
> +		fmtinfo = &unicam_image_formats[0];
> +		pix->pixelformat = fmtinfo->fourcc;
> +	}
> +
> +	unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
> +
> +	if (pix->field == V4L2_FIELD_ANY)
> +		pix->field = V4L2_FIELD_NONE;
> +
> +	return fmtinfo;
> +}
> +
> +static int unicam_try_fmt_vid(struct file *file, void *priv,
> +			      struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	__unicam_try_fmt_vid(node, &f->fmt.pix);
> +	return 0;
> +}
> +
> +static int unicam_s_fmt_vid(struct file *file, void *priv,
> +			    struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	if (vb2_is_busy(&node->buffer_queue))
> +		return -EBUSY;
> +
> +	node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
> +	node->fmt = *f;
> +
> +	return 0;
> +}
> +
> +static int unicam_enum_fmt_meta(struct file *file, void *priv,
> +				struct v4l2_fmtdesc *f)
> +{
> +	unsigned int i, index;
> +
> +	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
> +		if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
> +			continue;
> +		if (!unicam_meta_formats[i].metadata_fmt)
> +			continue;
> +
> +		if (index == f->index) {
> +			f->pixelformat = unicam_meta_formats[i].fourcc;
> +			f->type = V4L2_BUF_TYPE_META_CAPTURE;
> +			return 0;
> +		}
> +		index++;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int unicam_g_fmt_meta(struct file *file, void *priv,
> +			     struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	f->fmt.meta = node->fmt.fmt.meta;
> +
> +	return 0;
> +}
> +
> +static const struct unicam_format_info *
> +__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
> +{
> +	const struct unicam_format_info *fmtinfo;
> +
> +	/*
> +	 * Default to the first format if the requested pixel format code isn't
> +	 * supported.
> +	 */
> +	fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
> +					       UNICAM_SD_PAD_SOURCE_METADATA);
> +	if (!fmtinfo) {
> +		fmtinfo = &unicam_meta_formats[0];
> +		meta->dataformat = fmtinfo->fourcc;
> +	}
> +
> +	unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
> +
> +	return fmtinfo;
> +}
> +
> +static int unicam_try_fmt_meta(struct file *file, void *priv,
> +			       struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	__unicam_try_fmt_vid(node, &f->fmt.pix);
> +	return 0;
> +}
> +
> +static int unicam_s_fmt_meta(struct file *file, void *priv,
> +			     struct v4l2_format *f)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +
> +	if (vb2_is_busy(&node->buffer_queue))
> +		return -EBUSY;
> +
> +	node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
> +	node->fmt = *f;
> +
> +	return 0;
> +}
> +
> +static int unicam_enum_framesizes(struct file *file, void *fh,
> +				  struct v4l2_frmsizeenum *fsize)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +	int ret = -EINVAL;
> +
> +	if (fsize->index > 0)
> +		return ret;
> +
> +	if (is_image_node(node)) {
> +		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> +						  UNICAM_SD_PAD_SOURCE_IMAGE))
> +			return ret;
> +
> +		fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
> +		fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
> +		fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
> +		fsize->stepwise.step_width = 1;
> +		fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
> +		fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
> +		fsize->stepwise.step_height = 1;
> +	} else {
> +		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
> +						  UNICAM_SD_PAD_SOURCE_METADATA))
> +			return ret;
> +
> +		fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
> +		fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
> +		fsize->stepwise.step_width = 1;
> +		fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
> +		fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
> +		fsize->stepwise.step_height = 1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int unicam_log_status(struct file *file, void *fh)
> +{
> +	struct unicam_node *node = video_drvdata(file);
> +	struct unicam_device *unicam = node->dev;
> +	u32 reg;
> +
> +	/* status for sub devices */
> +	v4l2_device_call_all(&unicam->v4l2_dev, 0, core, log_status);
> +
> +	dev_info(unicam->dev, "-----Receiver status-----\n");
> +	dev_info(unicam->dev, "V4L2 width/height:   %ux%u\n",
> +		 node->fmt.fmt.pix.width, node->fmt.fmt.pix.height);
> +	dev_info(unicam->dev, "Mediabus format:     %08x\n",
> +		 node->fmtinfo->code);
> +	dev_info(unicam->dev, "V4L2 format:         %08x\n",
> +		 node->fmt.fmt.pix.pixelformat);
> +	reg = unicam_reg_read(unicam, UNICAM_IPIPE);
> +	dev_info(unicam->dev, "Unpacking/packing:   %u / %u\n",
> +		 unicam_get_field(reg, UNICAM_PUM_MASK),
> +		 unicam_get_field(reg, UNICAM_PPM_MASK));
> +	dev_info(unicam->dev, "----Live data----\n");
> +	dev_info(unicam->dev, "Programmed stride:   %4u\n",
> +		 unicam_reg_read(unicam, UNICAM_IBLS));
> +	dev_info(unicam->dev, "Detected resolution: %ux%u\n",
> +		 unicam_reg_read(unicam, UNICAM_IHSTA),
> +		 unicam_reg_read(unicam, UNICAM_IVSTA));
> +	dev_info(unicam->dev, "Write pointer:       %08x\n",
> +		 unicam_reg_read(unicam, UNICAM_IBWP));
> +
> +	return 0;
> +}
> +
> +static int unicam_subscribe_event(struct v4l2_fh *fh,
> +				  const struct v4l2_event_subscription *sub)
> +{
> +	switch (sub->type) {
> +	case V4L2_EVENT_FRAME_SYNC:
> +		return v4l2_event_subscribe(fh, sub, 2, NULL);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const struct v4l2_ioctl_ops unicam_ioctl_ops = {
> +	.vidioc_querycap		= unicam_querycap,
> +
> +	.vidioc_enum_fmt_vid_cap	= unicam_enum_fmt_vid,
> +	.vidioc_g_fmt_vid_cap		= unicam_g_fmt_vid,
> +	.vidioc_try_fmt_vid_cap		= unicam_try_fmt_vid,
> +	.vidioc_s_fmt_vid_cap		= unicam_s_fmt_vid,
> +
> +	.vidioc_enum_fmt_meta_cap	= unicam_enum_fmt_meta,
> +	.vidioc_g_fmt_meta_cap		= unicam_g_fmt_meta,
> +	.vidioc_try_fmt_meta_cap	= unicam_try_fmt_meta,
> +	.vidioc_s_fmt_meta_cap		= unicam_s_fmt_meta,
> +
> +	.vidioc_enum_framesizes		= unicam_enum_framesizes,
> +
> +	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
> +	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
> +	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
> +	.vidioc_querybuf		= vb2_ioctl_querybuf,
> +	.vidioc_qbuf			= vb2_ioctl_qbuf,
> +	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
> +	.vidioc_expbuf			= vb2_ioctl_expbuf,
> +	.vidioc_streamon		= vb2_ioctl_streamon,
> +	.vidioc_streamoff		= vb2_ioctl_streamoff,
> +
> +	.vidioc_log_status		= unicam_log_status,
> +	.vidioc_subscribe_event		= unicam_subscribe_event,
> +	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
> +};
> +
> +/* unicam capture driver file operations */
> +static const struct v4l2_file_operations unicam_fops = {
> +	.owner		= THIS_MODULE,
> +	.open           = v4l2_fh_open,
> +	.release        = vb2_fop_release,
> +	.poll		= vb2_fop_poll,
> +	.unlocked_ioctl = video_ioctl2,
> +	.mmap           = vb2_fop_mmap,
> +};
> +
> +static int unicam_video_link_validate(struct media_link *link)
> +{
> +	struct video_device *vdev =
> +		media_entity_to_video_device(link->sink->entity);
> +	struct v4l2_subdev *sd =
> +		media_entity_to_v4l2_subdev(link->source->entity);
> +	struct unicam_node *node = video_get_drvdata(vdev);
> +	const u32 pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
> +		      : UNICAM_SD_PAD_SOURCE_METADATA;
> +	const struct v4l2_mbus_framefmt *format;
> +	struct v4l2_subdev_state *state;
> +	int ret = 0;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> +	format = v4l2_subdev_state_get_format(state, pad, 0);
> +	if (!format) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (is_image_node(node)) {
> +		const struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> +
> +		if (node->fmtinfo->code != format->code ||
> +		    fmt->height != format->height ||
> +		    fmt->width != format->width ||
> +		    fmt->field != format->field) {
> +			dev_dbg(node->dev->dev,
> +				"image: (%u x %u) 0x%08x %s != (%u x %u) 0x%08x %s\n",
> +				fmt->width, fmt->height, node->fmtinfo->code,
> +				v4l2_field_names[fmt->field],
> +				format->width, format->height, format->code,
> +				v4l2_field_names[format->field]);
> +			ret = -EPIPE;
> +		};
> +	} else {
> +		const struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> +
> +		if (node->fmtinfo->code != format->code ||
> +		    fmt->height != format->height ||
> +		    fmt->width != format->width) {
> +			dev_dbg(node->dev->dev,
> +				"meta: (%u x %u) 0x%04x != (%u x %u) 0x%04x\n",
> +				fmt->width, fmt->height, node->fmtinfo->code,
> +				format->width, format->height, format->code);
> +			ret = -EPIPE;
> +		};
> +	}
> +
> +out:
> +	v4l2_subdev_unlock_state(state);
> +	return ret;
> +}
> +
> +static const struct media_entity_operations unicam_video_media_ops = {
> +	.link_validate = unicam_video_link_validate,
> +};
> +
> +static void unicam_node_release(struct video_device *vdev)
> +{
> +	struct unicam_node *node = video_get_drvdata(vdev);
> +
> +	unicam_put(node->dev);
> +}
> +
> +static void unicam_set_default_format(struct unicam_node *node)
> +{
> +	if (is_image_node(node)) {
> +		struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
> +
> +		node->fmtinfo = &unicam_image_formats[0];
> +		node->fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +
> +		v4l2_fill_pix_format(fmt, &unicam_default_image_format);
> +		fmt->pixelformat = node->fmtinfo->fourcc;
> +		unicam_calc_image_size_bpl(node->dev, node->fmtinfo, fmt);
> +	} else {
> +		struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
> +
> +		node->fmtinfo = &unicam_meta_formats[0];
> +		node->fmt.type = V4L2_BUF_TYPE_META_CAPTURE;
> +
> +		fmt->dataformat = node->fmtinfo->fourcc;
> +		fmt->width = unicam_default_meta_format.width;
> +		fmt->height = unicam_default_meta_format.height;
> +		unicam_calc_meta_size_bpl(node->dev, node->fmtinfo, fmt);
> +	}
> +}
> +
> +static int unicam_register_node(struct unicam_device *unicam,
> +				enum unicam_node_type type)
> +{
> +	const u32 pad_index = type == UNICAM_IMAGE_NODE
> +			    ? UNICAM_SD_PAD_SOURCE_IMAGE
> +			    : UNICAM_SD_PAD_SOURCE_METADATA;
> +	struct unicam_node *node = &unicam->node[type];
> +	struct video_device *vdev = &node->video_dev;
> +	struct vb2_queue *q = &node->buffer_queue;
> +	int ret;
> +
> +	node->dev = unicam_get(unicam);
> +	node->id = type;
> +
> +	spin_lock_init(&node->dma_queue_lock);
> +	mutex_init(&node->lock);
> +
> +	INIT_LIST_HEAD(&node->dma_queue);
> +
> +	/* Initialize the videobuf2 queue. */
> +	q->type = type == UNICAM_IMAGE_NODE ? V4L2_BUF_TYPE_VIDEO_CAPTURE
> +					    : V4L2_BUF_TYPE_META_CAPTURE;
> +	q->io_modes = VB2_MMAP | VB2_DMABUF;
> +	q->drv_priv = node;
> +	q->ops = &unicam_video_qops;
> +	q->mem_ops = &vb2_dma_contig_memops;
> +	q->buf_struct_size = sizeof(struct unicam_buffer);
> +	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> +	q->lock = &node->lock;
> +	q->min_queued_buffers = 1;
> +	q->dev = unicam->dev;
> +
> +	ret = vb2_queue_init(q);
> +	if (ret) {
> +		dev_err(unicam->dev, "vb2_queue_init() failed\n");
> +		goto err_unicam_put;
> +	}
> +
> +	/* Initialize the video device. */
> +	vdev->release = unicam_node_release;
> +	vdev->fops = &unicam_fops;
> +	vdev->ioctl_ops = &unicam_ioctl_ops;
> +	vdev->v4l2_dev = &unicam->v4l2_dev;
> +	vdev->vfl_dir = VFL_DIR_RX;
> +	vdev->queue = q;
> +	vdev->lock = &node->lock;
> +	vdev->device_caps = type == UNICAM_IMAGE_NODE
> +			  ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_META_CAPTURE;
> +	vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
> +	vdev->entity.ops = &unicam_video_media_ops;
> +
> +	snprintf(vdev->name, sizeof(vdev->name), "%s-%s", UNICAM_MODULE_NAME,
> +		 type == UNICAM_IMAGE_NODE ? "image" : "embedded");
> +
> +	video_set_drvdata(vdev, node);
> +
> +	if (type == UNICAM_IMAGE_NODE)
> +		vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
> +
> +	node->pad.flags = MEDIA_PAD_FL_SINK;
> +
> +	ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
> +	if (ret)
> +		goto err_unicam_put;
> +
> +	node->dummy_buf.size = UNICAM_DUMMY_BUF_SIZE;
> +	node->dummy_buf_cpu_addr = dma_alloc_coherent(unicam->dev,
> +						      node->dummy_buf.size,
> +						      &node->dummy_buf.dma_addr,
> +						      GFP_KERNEL);
> +	if (!node->dummy_buf_cpu_addr) {
> +		dev_err(unicam->dev, "Unable to allocate dummy buffer.\n");
> +		ret = -ENOMEM;
> +		goto err_entity_cleanup;
> +	}
> +
> +	unicam_set_default_format(node);
> +
> +	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register video device %s\n",
> +			vdev->name);
> +		goto err_dma_free;
> +	}
> +
> +	node->registered = true;
> +
> +	ret = media_create_pad_link(&unicam->subdev.sd.entity,
> +				    pad_index,
> +				    &node->video_dev.entity,
> +				    0,
> +				    MEDIA_LNK_FL_ENABLED |
> +				    MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret) {
> +		/*
> +		 * No need for cleanup, the caller will unregister the
> +		 * video device, which will drop the reference on the
> +		 * device and trigger the cleanup.
> +		 */
> +		dev_err(unicam->dev, "Unable to create pad link for %s\n",
> +			unicam->sensor.subdev->name);
> +		return ret;
> +	}
> +
> +	return 0;
> +
> +err_dma_free:
> +	dma_free_coherent(unicam->dev, node->dummy_buf.size,
> +			  node->dummy_buf_cpu_addr,
> +			  node->dummy_buf.dma_addr);
> +err_entity_cleanup:
> +	media_entity_cleanup(&vdev->entity);
> +err_unicam_put:
> +	unicam_put(unicam);
> +	return ret;
> +}
> +
> +static void unicam_unregister_nodes(struct unicam_device *unicam)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> +		struct unicam_node *node = &unicam->node[i];
> +
> +		if (node->dummy_buf_cpu_addr)
> +			dma_free_coherent(unicam->dev, node->dummy_buf.size,
> +					  node->dummy_buf_cpu_addr,
> +					  node->dummy_buf.dma_addr);
> +
> +		if (node->registered) {
> +			video_unregister_device(&node->video_dev);
> +			node->registered = false;
> +		}
> +	}
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Power management
> + */
> +
> +static int unicam_runtime_resume(struct device *dev)
> +{
> +	struct unicam_device *unicam = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = clk_set_min_rate(unicam->vpu_clock, UNICAM_MIN_VPU_CLOCK_RATE);
> +	if (ret) {
> +		dev_err(unicam->dev, "failed to set up VPU clock\n");
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(unicam->vpu_clock);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to enable VPU clock: %d\n", ret);
> +		goto err_vpu_clock;
> +	}
> +
> +	ret = clk_set_rate(unicam->clock, 100 * 1000 * 1000);
> +	if (ret) {
> +		dev_err(unicam->dev, "failed to set up CSI clock\n");
> +		goto err_vpu_prepare;
> +	}
> +
> +	ret = clk_prepare_enable(unicam->clock);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to enable CSI clock: %d\n", ret);
> +		goto err_vpu_prepare;
> +	}
> +
> +	return 0;
> +
> +err_vpu_prepare:
> +	clk_disable_unprepare(unicam->vpu_clock);
> +err_vpu_clock:
> +	if (clk_set_min_rate(unicam->vpu_clock, 0))
> +		dev_err(unicam->dev, "failed to reset the VPU clock\n");
> +
> +	return ret;
> +}
> +
> +static int unicam_runtime_suspend(struct device *dev)
> +{
> +	struct unicam_device *unicam = dev_get_drvdata(dev);
> +
> +	clk_disable_unprepare(unicam->clock);
> +
> +	if (clk_set_min_rate(unicam->vpu_clock, 0))
> +		dev_err(unicam->dev, "failed to reset the VPU clock\n");
> +
> +	clk_disable_unprepare(unicam->vpu_clock);
> +
> +	return 0;
> +}
> +
> +static const struct dev_pm_ops unicam_pm_ops = {
> +	RUNTIME_PM_OPS(unicam_runtime_suspend, unicam_runtime_resume, NULL)
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * V4L2 async notifier
> + */
> +
> +static int unicam_async_bound(struct v4l2_async_notifier *notifier,
> +			      struct v4l2_subdev *subdev,
> +			      struct v4l2_async_connection *asc)
> +{
> +	struct unicam_device *unicam = notifier_to_unicam_device(notifier);
> +	struct media_pad *sink = &unicam->subdev.pads[UNICAM_SD_PAD_SINK];
> +	struct media_pad *source;
> +	int ret;
> +
> +	dev_dbg(unicam->dev, "Using sensor %s for capture\n",
> +		subdev->name);
> +
> +	ret = v4l2_create_fwnode_links_to_pad(subdev, sink, MEDIA_LNK_FL_ENABLED |
> +					      MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret)
> +		return ret;
> +
> +	source = media_pad_remote_pad_unique(sink);
> +	if (!source) {
> +		dev_err(unicam->dev, "No connected sensor pad\n");
> +		return -ENOTCONN;
> +	}
> +
> +	unicam->sensor.subdev = subdev;
> +	unicam->sensor.pad = source;
> +
> +	return 0;
> +}
> +
> +static int unicam_async_complete(struct v4l2_async_notifier *notifier)
> +{
> +	struct unicam_device *unicam = notifier_to_unicam_device(notifier);
> +	int ret;
> +
> +	ret = unicam_register_node(unicam, UNICAM_IMAGE_NODE);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register image video device.\n");
> +		goto unregister;
> +	}
> +
> +	ret = unicam_register_node(unicam, UNICAM_METADATA_NODE);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register metadata video device.\n");
> +		goto unregister;
> +	}
> +
> +	ret = v4l2_device_register_subdev_nodes(&unicam->v4l2_dev);
> +	if (ret) {
> +		dev_err(unicam->dev, "Unable to register subdev nodes.\n");
> +		goto unregister;
> +	}
> +
> +	return 0;
> +
> +unregister:
> +	unicam_unregister_nodes(unicam);
> +	unicam_put(unicam);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_async_notifier_operations unicam_async_ops = {
> +	.bound = unicam_async_bound,
> +	.complete = unicam_async_complete,
> +};
> +
> +static int unicam_async_nf_init(struct unicam_device *unicam)
> +{
> +	struct v4l2_fwnode_endpoint ep = { };

If the bus-type property is mandatory and you have no stated defaults
anywhere, this is fine. I.e. all the relevant properties would need to be
mandatory.

> +	struct fwnode_handle *ep_handle;
> +	struct v4l2_async_connection *asc;
> +	int ret;
> +
> +	ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
> +				   &unicam->max_data_lanes);
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "Missing %s DT property\n",
> +			"brcm,num-data-lanes");
> +		return -EINVAL;
> +	}
> +
> +	/* Get and parse the local endpoint. */
> +	ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
> +						    FWNODE_GRAPH_ENDPOINT_NEXT);
> +	if (!ep_handle) {
> +		dev_err(unicam->dev, "No endpoint found\n");
> +		return -ENODEV;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
> +	if (ret) {
> +		dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
> +		goto error;
> +	}
> +
> +	unicam->bus_type = ep.bus_type;
> +
> +	switch (ep.bus_type) {
> +	case V4L2_MBUS_CSI2_DPHY: {
> +		unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
> +
> +		if (num_data_lanes != 1 && num_data_lanes != 2 &&
> +		    num_data_lanes != 4) {
> +			dev_err(unicam->dev, "%u data lanes not supported\n",
> +				num_data_lanes);
> +			goto error;
> +		}
> +
> +		if (num_data_lanes > unicam->max_data_lanes) {
> +			dev_err(unicam->dev,
> +				"Endpoint uses %u data lanes when %u are supported\n",
> +				num_data_lanes, unicam->max_data_lanes);
> +			goto error;
> +		}
> +
> +		unicam->active_data_lanes = num_data_lanes;
> +		unicam->bus_flags = ep.bus.mipi_csi2.flags;
> +		break;
> +	}
> +
> +	case V4L2_MBUS_CCP2:
> +		unicam->max_data_lanes = 1;
> +		unicam->active_data_lanes = 1;
> +		unicam->bus_flags = ep.bus.mipi_csi1.strobe;
> +		break;
> +
> +	default:
> +		/* Unsupported bus type */
> +		dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
> +		goto error;
> +	}
> +
> +	/* Initialize and register the async notifier. */
> +	v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
> +
> +	asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
> +					      struct v4l2_async_connection);
> +	fwnode_handle_put(ep_handle);
> +	ep_handle = NULL;
> +
> +	if (IS_ERR(asc)) {
> +		ret = PTR_ERR(asc);
> +		dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
> +			ret);
> +		goto error;
> +	}
> +
> +	unicam->notifier.ops = &unicam_async_ops;
> +
> +	ret = v4l2_async_nf_register(&unicam->notifier);
> +	if (ret) {
> +		dev_err(unicam->dev, "Error registering device notifier: %d\n",
> +			ret);
> +		goto error;
> +	}
> +
> +	return 0;
> +
> +error:
> +	fwnode_handle_put(ep_handle);
> +	return ret;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Probe & remove
> + */
> +
> +static int unicam_media_init(struct unicam_device *unicam)
> +{
> +	int ret;
> +
> +	unicam->mdev.dev = unicam->dev;
> +	strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
> +		sizeof(unicam->mdev.model));
> +	strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));

Isn't the field already zeroed?

> +	unicam->mdev.hw_revision = 0;
> +
> +	media_device_init(&unicam->mdev);
> +
> +	unicam->v4l2_dev.mdev = &unicam->mdev;
> +
> +	ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
> +	if (ret < 0) {
> +		dev_err(unicam->dev, "Unable to register v4l2 device\n");
> +		goto err_media_cleanup;
> +	}
> +
> +	ret = media_device_register(&unicam->mdev);
> +	if (ret < 0) {
> +		dev_err(unicam->dev,
> +			"Unable to register media-controller device\n");
> +		goto err_v4l2_unregister;
> +	}
> +
> +	return 0;
> +
> +err_v4l2_unregister:
> +	v4l2_device_unregister(&unicam->v4l2_dev);
> +err_media_cleanup:
> +	media_device_cleanup(&unicam->mdev);
> +	return ret;
> +}
> +
> +static int unicam_probe(struct platform_device *pdev)
> +{
> +	struct unicam_device *unicam;
> +	int ret;
> +
> +	unicam = kzalloc(sizeof(*unicam), GFP_KERNEL);
> +	if (!unicam)
> +		return -ENOMEM;
> +
> +	kref_init(&unicam->kref);
> +	unicam->dev = &pdev->dev;
> +	platform_set_drvdata(pdev, unicam);
> +
> +	unicam->base = devm_platform_ioremap_resource_byname(pdev, "unicam");
> +	if (IS_ERR(unicam->base)) {
> +		ret = PTR_ERR(unicam->base);
> +		goto err_unicam_put;
> +	}
> +
> +	unicam->clk_gate_base = devm_platform_ioremap_resource_byname(pdev, "cmi");
> +	if (IS_ERR(unicam->clk_gate_base)) {
> +		ret = PTR_ERR(unicam->clk_gate_base);
> +		goto err_unicam_put;
> +	}
> +
> +	unicam->clock = devm_clk_get(&pdev->dev, "lp");
> +	if (IS_ERR(unicam->clock)) {
> +		dev_err(unicam->dev, "Failed to get lp clock\n");
> +		ret = PTR_ERR(unicam->clock);
> +		goto err_unicam_put;
> +	}
> +
> +	unicam->vpu_clock = devm_clk_get(&pdev->dev, "vpu");
> +	if (IS_ERR(unicam->vpu_clock)) {
> +		dev_err(unicam->dev, "Failed to get vpu clock\n");
> +		ret = PTR_ERR(unicam->vpu_clock);
> +		goto err_unicam_put;
> +	}
> +
> +	ret = platform_get_irq(pdev, 0);
> +	if (ret <= 0) {
> +		dev_err(&pdev->dev, "No IRQ resource\n");
> +		ret = -EINVAL;
> +		goto err_unicam_put;
> +	}
> +
> +	ret = devm_request_irq(&pdev->dev, ret, unicam_isr, 0,
> +			       "unicam_capture0", unicam);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Unable to request interrupt\n");
> +		ret = -EINVAL;
> +		goto err_unicam_put;
> +	}
> +
> +	/* Enable the block power domain. */
> +	pm_runtime_enable(&pdev->dev);
> +
> +	ret = unicam_media_init(unicam);
> +	if (ret)
> +		goto err_pm_runtime;
> +
> +	ret = unicam_subdev_init(unicam);
> +	if (ret)
> +		goto err_media_unregister;
> +
> +	ret = unicam_async_nf_init(unicam);
> +	if (ret)
> +		goto err_subdev_unregister;
> +
> +	return 0;
> +
> +err_subdev_unregister:
> +	unicam_subdev_cleanup(unicam);
> +err_media_unregister:
> +	media_device_unregister(&unicam->mdev);
> +err_pm_runtime:
> +	pm_runtime_disable(&pdev->dev);
> +err_unicam_put:
> +	unicam_put(unicam);
> +
> +	return ret;
> +}
> +
> +static int unicam_remove(struct platform_device *pdev)
> +{
> +	struct unicam_device *unicam = platform_get_drvdata(pdev);
> +
> +	unicam_unregister_nodes(unicam);
> +	v4l2_device_unregister(&unicam->v4l2_dev);
> +	media_device_unregister(&unicam->mdev);
> +	v4l2_async_nf_unregister(&unicam->notifier);
> +
> +	unicam_subdev_cleanup(unicam);
> +
> +	unicam_put(unicam);
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id unicam_of_match[] = {
> +	{ .compatible = "brcm,bcm2835-unicam", },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, unicam_of_match);
> +
> +static struct platform_driver unicam_driver = {
> +	.probe		= unicam_probe,
> +	.remove		= unicam_remove,
> +	.driver = {
> +		.name	= UNICAM_MODULE_NAME,
> +		.pm	= pm_ptr(&unicam_pm_ops),
> +		.of_match_table = of_match_ptr(unicam_of_match),
> +	},
> +};
> +
> +module_platform_driver(unicam_driver);
> +
> +MODULE_AUTHOR("Dave Stevenson <[e-mail]>");
> +MODULE_DESCRIPTION("BCM2835 Unicam driver");
> +MODULE_LICENSE("GPL");

Laurent Pinchart March 26, 2024, 1:37 a.m. UTC | #11

Hi Sakari,

On Mon, Mar 25, 2024 at 06:36:49PM +0000, Sakari Ailus wrote:
> On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > From: Dave Stevenson <[e-mail]>
> > 
> > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > It is represented as two video device nodes: unicam-image and
> > unicam-embedded which are connected to an internal subdev (named
> > unicam-subdev) in order to manage streams routing.
> > 
> > Signed-off-by: Dave Stevenson <[e-mail]>
> > Co-developed-by: Naushir Patuck <[e-mail]>
> > Signed-off-by: Naushir Patuck <[e-mail]>
> > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > Co-developed-by: Laurent Pinchart <[e-mail]>
> > Signed-off-by: Laurent Pinchart <[e-mail]>
> 
> Thanks for submitting this, it's the cleanest and neatest Unicom driver

Unicam, or if you insist Unicorn, but not Unicom :-)

> I've ever seen!
> 
> Some mostly unimportant comments below, however the bus-type issue needs to
> be addressed.
> 
> > ---
> > Changes since v5:
> > 
> > - Move to drivers/media/platform/broadcom/
> > - Port to the upstream V4L2 streams API
> > - Rebase on latest metadata API proposal
> > - Add missing error message
> > - Drop unneeded documentation block for unicam_isr()
> > - Drop unneeded dev_dbg() and dev_err() messages
> > - Drop unneeded streams_mask and fmt checks
> > - Drop unused unicam_sd_pad_is_sink()
> > - Drop unneeded includes
> > - Drop v4l2_ctrl_subscribe_event() call
> > - Use pm_runtime_resume_and_get()
> > - Indentation and line wrap fixes
> > - Let the framework set bus_info
> > - Use v4l2_fwnode_endpoint_parse()
> > - Fix media device cleanup
> > - Drop lane reordering checks
> > - Fix subdev state locking
> > - Drop extra debug messages
> > - Move clock handling to runtime PM handlers
> > - Reorder functions
> > - Rename init functions for more clarity
> > - Initialize runtime PM earlier
> > - Clarify error messages
> > - Simplify subdev init with local variable
> > - Fix subdev cleanup
> > - Fix typos and indentation
> > - Don't initialize local variables needlessly
> > - Simplify num lanes check
> > - Fix metadata handling in subdev set_fmt
> > - Drop manual fallback to .s_stream()
> > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > - Simplify unicam_set_default_format()
> > - Fix default format settings
> > - Add busy check in unicam_s_fmt_meta()
> > - Add missing \n at end of format strings
> > - Fix metadata handling in subdev set_fmt
> > - Fix locking when starting streaming
> > - Return buffers from start streaming fails
> > - Fix format validation for metadata node
> > - Use video_device_pipeline_{start,stop}() helpers
> > - Simplify format enumeration
> > - Drop unset variable
> > - Update MAINTAINERS entry
> > - Update to the upstream v4l2_async_nf API
> > - Update to the latest subdev routing API
> > - Update to the latest subdev state API
> > - Move from subdev .init_cfg() to .init_state()
> > - Update to the latest videobuf2 API
> > - Fix v4l2_subdev_enable_streams() error check
> > - Use correct pad for the connected subdev
> > - Return buffers to vb2 when start streaming fails
> > - Improve debugging in start streaming handler
> > - Simplify DMA address management
> > - Drop comment about bcm2835-camera driver
> > - Clarify comments that explain min/max sizes
> > - Pass v4l2_pix_format to unicam_try_fmt()
> > - Drop unneeded local variables
> > - Rename image-related constants and functions
> > - Turn unicam_fmt.metadata_fmt into bool
> > - Rename unicam_fmt to unicam_format_info
> > - Rename unicam_format_info variables to fmtinfo
> > - Rename unicam_node.v_fmt to fmt
> > - Add metadata formats for RAW10, RAW12 and RAW14
> > - Make metadata formats line-based
> > - Validate format on metadata video device
> > - Add Co-devlopped-by tags
> > 
> > Changes since v3:
> > 
> > - Add the vendor prefix for DT name
> > - Use the reg-names in DT parsing
> > - Remove MAINTAINERS entry
> > 
> > Changes since v2:
> > 
> > - Change code organization
> > - Remove unused variables
> > - Correct the fmt_meta functions
> > - Rewrite the start/stop streaming
> >   - You can now start the image node alone, but not the metadata one
> >   - The buffers are allocated per-node
> >   - only the required stream is started, if the route exists and is
> >     enabled
> > - Prefix the macros with UNICAM_ to not have too generic names
> > - Drop colorspace support
> > 
> > Changes since v1:
> > 
> > - Replace the unicam_{info,debug,error} macros with dev_*()
> > ---
> >  MAINTAINERS                                   |    1 +
> >  drivers/media/platform/Kconfig                |    1 +
> >  drivers/media/platform/Makefile               |    1 +
> >  drivers/media/platform/broadcom/Kconfig       |   23 +
> >  drivers/media/platform/broadcom/Makefile      |    3 +
> >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> >  7 files changed, 2891 insertions(+)
> >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> >  create mode 100644 drivers/media/platform/broadcom/Makefile
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > 
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index e50a59654e6e..cc350729f467 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -4002,6 +4002,7 @@ M:	Raspberry Pi Kernel Maintenance <[e-mail]>
> >  L:	[e-mail]
> >  S:	Maintained
> >  F:	Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > +F:	drivers/media/platform/bcm2835/
> >  
> >  BROADCOM BCM47XX MIPS ARCHITECTURE
> >  M:	Hauke Mehrtens <[e-mail]>
> > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > index 91e54215de3a..2d79bfc68c15 100644
> > --- a/drivers/media/platform/Kconfig
> > +++ b/drivers/media/platform/Kconfig
> > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> >  source "drivers/media/platform/amphion/Kconfig"
> >  source "drivers/media/platform/aspeed/Kconfig"
> >  source "drivers/media/platform/atmel/Kconfig"
> > +source "drivers/media/platform/broadcom/Kconfig"
> >  source "drivers/media/platform/cadence/Kconfig"
> >  source "drivers/media/platform/chips-media/Kconfig"
> >  source "drivers/media/platform/intel/Kconfig"
> > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > index 3296ec1ebe16..da17301f7439 100644
> > --- a/drivers/media/platform/Makefile
> > +++ b/drivers/media/platform/Makefile
> > @@ -10,6 +10,7 @@ obj-y += amlogic/
> >  obj-y += amphion/
> >  obj-y += aspeed/
> >  obj-y += atmel/
> > +obj-y += broadcom/
> >  obj-y += cadence/
> >  obj-y += chips-media/
> >  obj-y += intel/
> > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > new file mode 100644
> > index 000000000000..cc2c9afcc948
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/Kconfig
> > @@ -0,0 +1,23 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +config VIDEO_BCM2835_UNICAM
> > +	tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > +	depends on ARCH_BCM2835 || COMPILE_TEST
> > +	depends on PM
> > +	depends on VIDEO_DEV
> > +	select MEDIA_CONTROLLER
> > +	select V4L2_FWNODE
> > +	select VIDEO_V4L2_SUBDEV_API
> > +	select VIDEOBUF2_DMA_CONTIG
> > +	help
> > +	  Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > +	  This is a V4L2 driver that controls the CSI-2 receiver directly,
> > +	  independently from the VC4 firmware.
> > +
> > +	  This driver is mutually exclusive with the use of bcm2835-camera. The
> > +	  firmware will disable all access to the peripheral from within the
> > +	  firmware if it finds a DT node using it, and bcm2835-camera will
> > +	  therefore fail to probe.
> > +
> > +	  To compile this driver as a module, choose M here. The module will be
> > +	  called bcm2835-unicam.
> > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > new file mode 100644
> > index 000000000000..03d2045aba2e
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/Makefile
> > @@ -0,0 +1,3 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +
> > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > new file mode 100644
> > index 000000000000..84775fd2fac5
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > @@ -0,0 +1,255 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +
> > +/*
> > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> 
> Anything up to 2024?

Not really. The registers haven't really changed :-) I'll update the
copyright in the .c file though.

> > + * Dave Stevenson <[e-mail]>
> > + */

[snip]

> > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > new file mode 100644
> > index 000000000000..716c89b8a217
> > --- /dev/null
> > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > @@ -0,0 +1,2607 @@

[snip]

> > +static irqreturn_t unicam_isr(int irq, void *dev)
> > +{
> > +	struct unicam_device *unicam = dev;
> > +	unsigned int lines_done = unicam_get_lines_done(dev);
> > +	unsigned int sequence = unicam->sequence;
> > +	unsigned int i;
> > +	u32 ista, sta;
> > +	bool fe;
> > +	u64 ts;
> > +
> > +	sta = unicam_reg_read(unicam, UNICAM_STA);
> > +	/* Write value back to clear the interrupts */
> > +	unicam_reg_write(unicam, UNICAM_STA, sta);
> > +
> > +	ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > +	/* Write value back to clear the interrupts */
> > +	unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > +
> > +	dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > +		ista, sta, sequence, lines_done);
> > +
> > +	if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > +		return IRQ_HANDLED;
> > +
> > +	/*
> > +	 * Look for either the Frame End interrupt or the Packet Capture status
> > +	 * to signal a frame end.
> > +	 */
> > +	fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > +
> > +	/*
> > +	 * We must run the frame end handler first. If we have a valid next_frm
> > +	 * and we get a simultaneout FE + FS interrupt, running the FS handler
> > +	 * first would null out the next_frm ptr and we would have lost the
> > +	 * buffer forever.
> > +	 */
> > +	if (fe) {
> > +		/*
> > +		 * Ensure we have swapped buffers already as we can't
> > +		 * stop the peripheral. If no buffer is available, use a
> > +		 * dummy buffer to dump out frames until we get a new buffer
> > +		 * to use.
> > +		 */
> > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +			if (!unicam->node[i].streaming)
> > +				continue;
> > +
> > +			/*
> > +			 * If cur_frm == next_frm, it means we have not had
> > +			 * a chance to swap buffers, likely due to having
> > +			 * multiple interrupts occurring simultaneously (like FE
> > +			 * + FS + LS). In this case, we cannot signal the buffer
> > +			 * as complete, as the HW will reuse that buffer.
> > +			 */
> > +			if (unicam->node[i].cur_frm &&
> > +			    unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > +				unicam_process_buffer_complete(&unicam->node[i],
> > +							       sequence);
> > +			unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > +		}
> > +		unicam->sequence++;
> 
> Does access to this data need to be serialised somehow.

Given that it's only accessed from the interrupt handler (beside
start_streaming time, before starting the hardware), I don't think so.

> > +	}
> > +
> > +	if (ista & UNICAM_FSI) {
> > +		/*
> > +		 * Timestamp is to be when the first data byte was captured,
> > +		 * aka frame start.
> > +		 */
> > +		ts = ktime_get_ns();
> > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +			if (!unicam->node[i].streaming)
> > +				continue;
> > +
> > +			if (unicam->node[i].cur_frm)
> > +				unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > +								ts;
> > +			else
> > +				dev_dbg(unicam->v4l2_dev.dev,
> > +					"ISR: [%d] Dropping frame, buffer not available at FS\n",
> > +					i);
> > +			/*
> > +			 * Set the next frame output to go to a dummy frame
> > +			 * if we have not managed to obtain another frame
> > +			 * from the queue.
> > +			 */
> > +			unicam_schedule_dummy_buffer(&unicam->node[i]);
> > +		}
> > +
> > +		unicam_queue_event_sof(unicam);
> > +	}
> > +
> > +	/*
> > +	 * Cannot swap buffer at frame end, there may be a race condition
> > +	 * where the HW does not actually swap it if the new frame has
> > +	 * already started.
> > +	 */
> > +	if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > +			if (!unicam->node[i].streaming)
> > +				continue;
> > +
> > +			spin_lock(&unicam->node[i].dma_queue_lock);
> > +			if (!list_empty(&unicam->node[i].dma_queue) &&
> > +			    !unicam->node[i].next_frm)
> > +				unicam_schedule_next_buffer(&unicam->node[i]);
> > +			spin_unlock(&unicam->node[i].dma_queue_lock);
> > +		}
> > +	}
> > +
> > +	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > +		/* Switch out of trigger mode if selected */
> > +		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > +		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > +	}
> > +	return IRQ_HANDLED;
> > +}
> > +
> > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > +{
> > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +	u32 pack, unpack;
> > +	u32 val;
> > +
> > +	if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > +		unpack = UNICAM_PUM_NONE;
> > +		pack = UNICAM_PPM_NONE;
> > +	} else {
> > +		switch (node->fmtinfo->depth) {
> > +		case 8:
> > +			unpack = UNICAM_PUM_UNPACK8;
> > +			break;
> > +		case 10:
> > +			unpack = UNICAM_PUM_UNPACK10;
> > +			break;
> > +		case 12:
> > +			unpack = UNICAM_PUM_UNPACK12;
> > +			break;
> > +		case 14:
> > +			unpack = UNICAM_PUM_UNPACK14;
> > +			break;
> > +		case 16:
> > +			unpack = UNICAM_PUM_UNPACK16;
> > +			break;
> > +		default:
> > +			unpack = UNICAM_PUM_NONE;
> > +			break;
> > +		}
> > +
> > +		/* Repacking is always to 16bpp */
> > +		pack = UNICAM_PPM_PACK16;
> 
> Also 8-bit data?

Not that I know of. The 8-bit entries in unicam_image_formats have no
.unpacked_fourcc field, so the condition in the if above will always be
true for those as they can only be selected by setting the pixel format
to fmtinfo->fourcc.

> > +	}
> > +
> > +	val = 0;
> 
> You could do initialisation in declaration.

Yes, but I think it's more readable to keep all the code that affects
the 'val' variable together.

> > +	unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> > +	unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> > +	unicam_reg_write(unicam, UNICAM_IPIPE, val);
> > +}
> > +
> > +static void unicam_cfg_image_id(struct unicam_device *unicam)
> > +{
> > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +
> > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +		/* CSI2 mode, hardcode VC 0 for now. */
> > +		unicam_reg_write(unicam, UNICAM_IDI0,
> > +				 (0 << 6) | node->fmtinfo->csi_dt);
> > +	} else {
> > +		/* CCP2 mode */
> > +		unicam_reg_write(unicam, UNICAM_IDI0,
> > +				 0x80 | node->fmtinfo->csi_dt);
> > +	}
> > +}
> > +
> > +static void unicam_enable_ed(struct unicam_device *unicam)
> > +{
> > +	u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> > +
> > +	unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> > +	/* Do not wrap at the end of the embedded data buffer */
> > +	unicam_set_field(&val, 0, UNICAM_DBOB);
> > +
> > +	unicam_reg_write(unicam, UNICAM_DCS, val);
> > +}
> > +
> > +static void unicam_start_rx(struct unicam_device *unicam,
> > +			    struct unicam_buffer *buf)
> > +{
> > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > +	int line_int_freq = node->fmt.fmt.pix.height >> 2;
> > +	unsigned int i;
> > +	u32 val;
> > +
> > +	if (line_int_freq < 128)
> > +		line_int_freq = 128;
> 
> 	line_int_freq = max(line_int_freq, 128);
Ack.

> > +
> > +	/* Enable lane clocks */
> > +	val = 1;
> 
> Initialise in the loop initialisation below, I'd say.

How about

	val = 0x55 & GENMASK(unicam->pipe.num_data_lanes * 2 - 1, 0);

?

> > +	for (i = 0; i < unicam->active_data_lanes; i++)
> > +		val = val << 2 | 1;
> > +	unicam_clk_write(unicam, val);
> > +
> > +	/* Basic init */
> > +	unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> > +
> > +	/* Enable analogue control, and leave in reset. */
> > +	val = UNICAM_AR;
> > +	unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> > +	unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> > +	unicam_reg_write(unicam, UNICAM_ANA, val);
> > +	usleep_range(1000, 2000);
> > +
> > +	/* Come out of reset */
> > +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> > +
> > +	/* Peripheral reset */
> > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > +
> > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > +
> > +	/* Enable Rx control. */
> > +	val = unicam_reg_read(unicam, UNICAM_CTRL);
> > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +		unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> > +		unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> > +	} else {
> > +		unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> > +		unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> > +	}
> > +	/* Packet framer timeout */
> > +	unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> > +	unicam_set_field(&val, 128, UNICAM_OET_MASK);
> > +	unicam_reg_write(unicam, UNICAM_CTRL, val);
> > +
> > +	unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> > +	unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> > +
> > +	/* AXI bus access QoS setup */
> > +	val = unicam_reg_read(unicam, UNICAM_PRI);
> > +	unicam_set_field(&val, 0, UNICAM_BL_MASK);
> > +	unicam_set_field(&val, 0, UNICAM_BS_MASK);
> > +	unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> > +	unicam_set_field(&val, 8, UNICAM_NP_MASK);
> > +	unicam_set_field(&val, 2, UNICAM_PT_MASK);
> > +	unicam_set_field(&val, 1, UNICAM_PE);
> > +	unicam_reg_write(unicam, UNICAM_PRI, val);
> > +
> > +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> > +
> > +	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
> > +	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> > +	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> > +	unicam_reg_write(unicam, UNICAM_ICTL, val);
> > +	unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> > +	unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> > +
> > +	/* tclk_term_en */
> > +	unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> > +	/* tclk_settle */
> > +	unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> > +	/* td_term_en */
> > +	unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> > +	/* ths_settle */
> > +	unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> > +	/* trx_enable */
> > +	unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> > +
> > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> > +
> > +	/* Packet compare setup - required to avoid missing frame ends */
> > +	val = 0;
> > +	unicam_set_field(&val, 1, UNICAM_PCE);
> > +	unicam_set_field(&val, 1, UNICAM_GI);
> > +	unicam_set_field(&val, 1, UNICAM_CPH);
> > +	unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> > +	unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> > +	unicam_reg_write(unicam, UNICAM_CMP0, val);
> > +
> > +	/* Enable clock lane and set up terminations */
> > +	val = 0;
> > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +		/* CSI2 */
> > +		unicam_set_field(&val, 1, UNICAM_CLE);
> > +		unicam_set_field(&val, 1, UNICAM_CLLPE);
> > +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > +			unicam_set_field(&val, 1, UNICAM_CLTRE);
> > +			unicam_set_field(&val, 1, UNICAM_CLHSE);
> > +		}
> > +	} else {
> > +		/* CCP2 */
> > +		unicam_set_field(&val, 1, UNICAM_CLE);
> > +		unicam_set_field(&val, 1, UNICAM_CLHSE);
> > +		unicam_set_field(&val, 1, UNICAM_CLTRE);
> > +	}
> > +	unicam_reg_write(unicam, UNICAM_CLK, val);
> > +
> > +	/*
> > +	 * Enable required data lanes with appropriate terminations.
> > +	 * The same value needs to be written to UNICAM_DATn registers for
> > +	 * the active lanes, and 0 for inactive ones.
> > +	 */
> > +	val = 0;
> > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > +		/* CSI2 */
> > +		unicam_set_field(&val, 1, UNICAM_DLE);
> > +		unicam_set_field(&val, 1, UNICAM_DLLPE);
> > +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > +			unicam_set_field(&val, 1, UNICAM_DLTRE);
> > +			unicam_set_field(&val, 1, UNICAM_DLHSE);
> > +		}
> > +	} else {
> > +		/* CCP2 */
> > +		unicam_set_field(&val, 1, UNICAM_DLE);
> > +		unicam_set_field(&val, 1, UNICAM_DLHSE);
> > +		unicam_set_field(&val, 1, UNICAM_DLTRE);
> > +	}
> > +	unicam_reg_write(unicam, UNICAM_DAT0, val);
> > +
> > +	if (unicam->active_data_lanes == 1)
> > +		val = 0;
> > +	unicam_reg_write(unicam, UNICAM_DAT1, val);
> > +
> > +	if (unicam->max_data_lanes > 2) {
> > +		/*
> > +		 * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> > +		 * instance supports more than 2 data lanes.
> > +		 */
> > +		if (unicam->active_data_lanes == 2)
> > +			val = 0;
> > +		unicam_reg_write(unicam, UNICAM_DAT2, val);
> > +
> > +		if (unicam->active_data_lanes == 3)
> > +			val = 0;
> > +		unicam_reg_write(unicam, UNICAM_DAT3, val);
> > +	}
> > +
> > +	unicam_reg_write(unicam, UNICAM_IBLS,
> > +			 node->fmt.fmt.pix.bytesperline);
> > +	unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> > +	unicam_set_packing_config(unicam);
> > +	unicam_cfg_image_id(unicam);
> > +
> > +	val = unicam_reg_read(unicam, UNICAM_MISC);
> > +	unicam_set_field(&val, 1, UNICAM_FL0);
> > +	unicam_set_field(&val, 1, UNICAM_FL1);
> > +	unicam_reg_write(unicam, UNICAM_MISC, val);
> > +
> > +	/* Enable peripheral */
> > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> > +
> > +	/* Load image pointers */
> > +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> > +
> > +	/*
> > +	 * Enable trigger only for the first frame to
> > +	 * sync correctly to the FS from the source.
> > +	 */
> > +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > +}

[snip]

> > +static int unicam_async_nf_init(struct unicam_device *unicam)
> > +{
> > +	struct v4l2_fwnode_endpoint ep = { };
> 
> If the bus-type property is mandatory and you have no stated defaults
> anywhere, this is fine. I.e. all the relevant properties would need to be
> mandatory.

They are, as far as I can tell (well, the clock-noncontinuous property
is not mandatory, but that's expected as it's a flag).

> > +	struct fwnode_handle *ep_handle;
> > +	struct v4l2_async_connection *asc;
> > +	int ret;
> > +
> > +	ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
> > +				   &unicam->max_data_lanes);
> > +	if (ret < 0) {
> > +		dev_err(unicam->dev, "Missing %s DT property\n",
> > +			"brcm,num-data-lanes");
> > +		return -EINVAL;
> > +	}
> > +
> > +	/* Get and parse the local endpoint. */
> > +	ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
> > +						    FWNODE_GRAPH_ENDPOINT_NEXT);
> > +	if (!ep_handle) {
> > +		dev_err(unicam->dev, "No endpoint found\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
> > +	if (ret) {
> > +		dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
> > +		goto error;
> > +	}
> > +
> > +	unicam->bus_type = ep.bus_type;
> > +
> > +	switch (ep.bus_type) {
> > +	case V4L2_MBUS_CSI2_DPHY: {
> > +		unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
> > +
> > +		if (num_data_lanes != 1 && num_data_lanes != 2 &&
> > +		    num_data_lanes != 4) {
> > +			dev_err(unicam->dev, "%u data lanes not supported\n",
> > +				num_data_lanes);
> > +			goto error;
> > +		}
> > +
> > +		if (num_data_lanes > unicam->max_data_lanes) {
> > +			dev_err(unicam->dev,
> > +				"Endpoint uses %u data lanes when %u are supported\n",
> > +				num_data_lanes, unicam->max_data_lanes);
> > +			goto error;
> > +		}
> > +
> > +		unicam->active_data_lanes = num_data_lanes;
> > +		unicam->bus_flags = ep.bus.mipi_csi2.flags;
> > +		break;
> > +	}
> > +
> > +	case V4L2_MBUS_CCP2:
> > +		unicam->max_data_lanes = 1;
> > +		unicam->active_data_lanes = 1;
> > +		unicam->bus_flags = ep.bus.mipi_csi1.strobe;
> > +		break;
> > +
> > +	default:
> > +		/* Unsupported bus type */
> > +		dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
> > +		goto error;
> > +	}
> > +
> > +	/* Initialize and register the async notifier. */
> > +	v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
> > +
> > +	asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
> > +					      struct v4l2_async_connection);
> > +	fwnode_handle_put(ep_handle);
> > +	ep_handle = NULL;
> > +
> > +	if (IS_ERR(asc)) {
> > +		ret = PTR_ERR(asc);
> > +		dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
> > +			ret);
> > +		goto error;
> > +	}
> > +
> > +	unicam->notifier.ops = &unicam_async_ops;
> > +
> > +	ret = v4l2_async_nf_register(&unicam->notifier);
> > +	if (ret) {
> > +		dev_err(unicam->dev, "Error registering device notifier: %d\n",
> > +			ret);
> > +		goto error;
> > +	}
> > +
> > +	return 0;
> > +
> > +error:
> > +	fwnode_handle_put(ep_handle);
> > +	return ret;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Probe & remove
> > + */
> > +
> > +static int unicam_media_init(struct unicam_device *unicam)
> > +{
> > +	int ret;
> > +
> > +	unicam->mdev.dev = unicam->dev;
> > +	strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
> > +		sizeof(unicam->mdev.model));
> > +	strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));
> 
> Isn't the field already zeroed?

Indeed. I'll drop this.

> 
> > +	unicam->mdev.hw_revision = 0;
> > +
> > +	media_device_init(&unicam->mdev);
> > +
> > +	unicam->v4l2_dev.mdev = &unicam->mdev;
> > +
> > +	ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
> > +	if (ret < 0) {
> > +		dev_err(unicam->dev, "Unable to register v4l2 device\n");
> > +		goto err_media_cleanup;
> > +	}
> > +
> > +	ret = media_device_register(&unicam->mdev);
> > +	if (ret < 0) {
> > +		dev_err(unicam->dev,
> > +			"Unable to register media-controller device\n");
> > +		goto err_v4l2_unregister;
> > +	}
> > +
> > +	return 0;
> > +
> > +err_v4l2_unregister:
> > +	v4l2_device_unregister(&unicam->v4l2_dev);
> > +err_media_cleanup:
> > +	media_device_cleanup(&unicam->mdev);
> > +	return ret;
> > +}

[snip]

Laurent Pinchart March 26, 2024, 1:50 a.m. UTC | #12

On Tue, Mar 26, 2024 at 03:37:09AM +0200, Laurent Pinchart wrote:
> Hi Sakari,
> 
> On Mon, Mar 25, 2024 at 06:36:49PM +0000, Sakari Ailus wrote:
> > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > From: Dave Stevenson <[e-mail]>
> > > 
> > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > It is represented as two video device nodes: unicam-image and
> > > unicam-embedded which are connected to an internal subdev (named
> > > unicam-subdev) in order to manage streams routing.
> > > 
> > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > 
> > Thanks for submitting this, it's the cleanest and neatest Unicom driver
> 
> Unicam, or if you insist Unicorn, but not Unicom :-)
> 
> > I've ever seen!
> > 
> > Some mostly unimportant comments below, however the bus-type issue needs to
> > be addressed.
> > 
> > > ---
> > > Changes since v5:
> > > 
> > > - Move to drivers/media/platform/broadcom/
> > > - Port to the upstream V4L2 streams API
> > > - Rebase on latest metadata API proposal
> > > - Add missing error message
> > > - Drop unneeded documentation block for unicam_isr()
> > > - Drop unneeded dev_dbg() and dev_err() messages
> > > - Drop unneeded streams_mask and fmt checks
> > > - Drop unused unicam_sd_pad_is_sink()
> > > - Drop unneeded includes
> > > - Drop v4l2_ctrl_subscribe_event() call
> > > - Use pm_runtime_resume_and_get()
> > > - Indentation and line wrap fixes
> > > - Let the framework set bus_info
> > > - Use v4l2_fwnode_endpoint_parse()
> > > - Fix media device cleanup
> > > - Drop lane reordering checks
> > > - Fix subdev state locking
> > > - Drop extra debug messages
> > > - Move clock handling to runtime PM handlers
> > > - Reorder functions
> > > - Rename init functions for more clarity
> > > - Initialize runtime PM earlier
> > > - Clarify error messages
> > > - Simplify subdev init with local variable
> > > - Fix subdev cleanup
> > > - Fix typos and indentation
> > > - Don't initialize local variables needlessly
> > > - Simplify num lanes check
> > > - Fix metadata handling in subdev set_fmt
> > > - Drop manual fallback to .s_stream()
> > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > - Simplify unicam_set_default_format()
> > > - Fix default format settings
> > > - Add busy check in unicam_s_fmt_meta()
> > > - Add missing \n at end of format strings
> > > - Fix metadata handling in subdev set_fmt
> > > - Fix locking when starting streaming
> > > - Return buffers from start streaming fails
> > > - Fix format validation for metadata node
> > > - Use video_device_pipeline_{start,stop}() helpers
> > > - Simplify format enumeration
> > > - Drop unset variable
> > > - Update MAINTAINERS entry
> > > - Update to the upstream v4l2_async_nf API
> > > - Update to the latest subdev routing API
> > > - Update to the latest subdev state API
> > > - Move from subdev .init_cfg() to .init_state()
> > > - Update to the latest videobuf2 API
> > > - Fix v4l2_subdev_enable_streams() error check
> > > - Use correct pad for the connected subdev
> > > - Return buffers to vb2 when start streaming fails
> > > - Improve debugging in start streaming handler
> > > - Simplify DMA address management
> > > - Drop comment about bcm2835-camera driver
> > > - Clarify comments that explain min/max sizes
> > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > - Drop unneeded local variables
> > > - Rename image-related constants and functions
> > > - Turn unicam_fmt.metadata_fmt into bool
> > > - Rename unicam_fmt to unicam_format_info
> > > - Rename unicam_format_info variables to fmtinfo
> > > - Rename unicam_node.v_fmt to fmt
> > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > - Make metadata formats line-based
> > > - Validate format on metadata video device
> > > - Add Co-devlopped-by tags
> > > 
> > > Changes since v3:
> > > 
> > > - Add the vendor prefix for DT name
> > > - Use the reg-names in DT parsing
> > > - Remove MAINTAINERS entry
> > > 
> > > Changes since v2:
> > > 
> > > - Change code organization
> > > - Remove unused variables
> > > - Correct the fmt_meta functions
> > > - Rewrite the start/stop streaming
> > >   - You can now start the image node alone, but not the metadata one
> > >   - The buffers are allocated per-node
> > >   - only the required stream is started, if the route exists and is
> > >     enabled
> > > - Prefix the macros with UNICAM_ to not have too generic names
> > > - Drop colorspace support
> > > 
> > > Changes since v1:
> > > 
> > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > ---
> > >  MAINTAINERS                                   |    1 +
> > >  drivers/media/platform/Kconfig                |    1 +
> > >  drivers/media/platform/Makefile               |    1 +
> > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > >  7 files changed, 2891 insertions(+)
> > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > > 
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index e50a59654e6e..cc350729f467 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -4002,6 +4002,7 @@ M:	Raspberry Pi Kernel Maintenance <[e-mail]>
> > >  L:	[e-mail]
> > >  S:	Maintained
> > >  F:	Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > > +F:	drivers/media/platform/bcm2835/
> > >  
> > >  BROADCOM BCM47XX MIPS ARCHITECTURE
> > >  M:	Hauke Mehrtens <[e-mail]>
> > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > index 91e54215de3a..2d79bfc68c15 100644
> > > --- a/drivers/media/platform/Kconfig
> > > +++ b/drivers/media/platform/Kconfig
> > > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> > >  source "drivers/media/platform/amphion/Kconfig"
> > >  source "drivers/media/platform/aspeed/Kconfig"
> > >  source "drivers/media/platform/atmel/Kconfig"
> > > +source "drivers/media/platform/broadcom/Kconfig"
> > >  source "drivers/media/platform/cadence/Kconfig"
> > >  source "drivers/media/platform/chips-media/Kconfig"
> > >  source "drivers/media/platform/intel/Kconfig"
> > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > > index 3296ec1ebe16..da17301f7439 100644
> > > --- a/drivers/media/platform/Makefile
> > > +++ b/drivers/media/platform/Makefile
> > > @@ -10,6 +10,7 @@ obj-y += amlogic/
> > >  obj-y += amphion/
> > >  obj-y += aspeed/
> > >  obj-y += atmel/
> > > +obj-y += broadcom/
> > >  obj-y += cadence/
> > >  obj-y += chips-media/
> > >  obj-y += intel/
> > > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > > new file mode 100644
> > > index 000000000000..cc2c9afcc948
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/Kconfig
> > > @@ -0,0 +1,23 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +config VIDEO_BCM2835_UNICAM
> > > +	tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > > +	depends on ARCH_BCM2835 || COMPILE_TEST
> > > +	depends on PM
> > > +	depends on VIDEO_DEV
> > > +	select MEDIA_CONTROLLER
> > > +	select V4L2_FWNODE
> > > +	select VIDEO_V4L2_SUBDEV_API
> > > +	select VIDEOBUF2_DMA_CONTIG
> > > +	help
> > > +	  Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > > +	  This is a V4L2 driver that controls the CSI-2 receiver directly,
> > > +	  independently from the VC4 firmware.
> > > +
> > > +	  This driver is mutually exclusive with the use of bcm2835-camera. The
> > > +	  firmware will disable all access to the peripheral from within the
> > > +	  firmware if it finds a DT node using it, and bcm2835-camera will
> > > +	  therefore fail to probe.
> > > +
> > > +	  To compile this driver as a module, choose M here. The module will be
> > > +	  called bcm2835-unicam.
> > > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > > new file mode 100644
> > > index 000000000000..03d2045aba2e
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/Makefile
> > > @@ -0,0 +1,3 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > new file mode 100644
> > > index 000000000000..84775fd2fac5
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > @@ -0,0 +1,255 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +
> > > +/*
> > > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> > 
> > Anything up to 2024?
> 
> Not really. The registers haven't really changed :-) I'll update the
> copyright in the .c file though.
> 
> > > + * Dave Stevenson <[e-mail]>
> > > + */
> 
> [snip]
> 
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > new file mode 100644
> > > index 000000000000..716c89b8a217
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > @@ -0,0 +1,2607 @@
> 
> [snip]
> 
> > > +static irqreturn_t unicam_isr(int irq, void *dev)
> > > +{
> > > +	struct unicam_device *unicam = dev;
> > > +	unsigned int lines_done = unicam_get_lines_done(dev);
> > > +	unsigned int sequence = unicam->sequence;
> > > +	unsigned int i;
> > > +	u32 ista, sta;
> > > +	bool fe;
> > > +	u64 ts;
> > > +
> > > +	sta = unicam_reg_read(unicam, UNICAM_STA);
> > > +	/* Write value back to clear the interrupts */
> > > +	unicam_reg_write(unicam, UNICAM_STA, sta);
> > > +
> > > +	ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > > +	/* Write value back to clear the interrupts */
> > > +	unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > > +
> > > +	dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > > +		ista, sta, sequence, lines_done);
> > > +
> > > +	if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > > +		return IRQ_HANDLED;
> > > +
> > > +	/*
> > > +	 * Look for either the Frame End interrupt or the Packet Capture status
> > > +	 * to signal a frame end.
> > > +	 */
> > > +	fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > > +
> > > +	/*
> > > +	 * We must run the frame end handler first. If we have a valid next_frm
> > > +	 * and we get a simultaneout FE + FS interrupt, running the FS handler
> > > +	 * first would null out the next_frm ptr and we would have lost the
> > > +	 * buffer forever.
> > > +	 */
> > > +	if (fe) {
> > > +		/*
> > > +		 * Ensure we have swapped buffers already as we can't
> > > +		 * stop the peripheral. If no buffer is available, use a
> > > +		 * dummy buffer to dump out frames until we get a new buffer
> > > +		 * to use.
> > > +		 */
> > > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +			if (!unicam->node[i].streaming)
> > > +				continue;
> > > +
> > > +			/*
> > > +			 * If cur_frm == next_frm, it means we have not had
> > > +			 * a chance to swap buffers, likely due to having
> > > +			 * multiple interrupts occurring simultaneously (like FE
> > > +			 * + FS + LS). In this case, we cannot signal the buffer
> > > +			 * as complete, as the HW will reuse that buffer.
> > > +			 */
> > > +			if (unicam->node[i].cur_frm &&
> > > +			    unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > > +				unicam_process_buffer_complete(&unicam->node[i],
> > > +							       sequence);
> > > +			unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > > +		}
> > > +		unicam->sequence++;
> > 
> > Does access to this data need to be serialised somehow.
> 
> Given that it's only accessed from the interrupt handler (beside
> start_streaming time, before starting the hardware), I don't think so.
> 
> > > +	}
> > > +
> > > +	if (ista & UNICAM_FSI) {
> > > +		/*
> > > +		 * Timestamp is to be when the first data byte was captured,
> > > +		 * aka frame start.
> > > +		 */
> > > +		ts = ktime_get_ns();
> > > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +			if (!unicam->node[i].streaming)
> > > +				continue;
> > > +
> > > +			if (unicam->node[i].cur_frm)
> > > +				unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > > +								ts;
> > > +			else
> > > +				dev_dbg(unicam->v4l2_dev.dev,
> > > +					"ISR: [%d] Dropping frame, buffer not available at FS\n",
> > > +					i);
> > > +			/*
> > > +			 * Set the next frame output to go to a dummy frame
> > > +			 * if we have not managed to obtain another frame
> > > +			 * from the queue.
> > > +			 */
> > > +			unicam_schedule_dummy_buffer(&unicam->node[i]);
> > > +		}
> > > +
> > > +		unicam_queue_event_sof(unicam);
> > > +	}
> > > +
> > > +	/*
> > > +	 * Cannot swap buffer at frame end, there may be a race condition
> > > +	 * where the HW does not actually swap it if the new frame has
> > > +	 * already started.
> > > +	 */
> > > +	if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +			if (!unicam->node[i].streaming)
> > > +				continue;
> > > +
> > > +			spin_lock(&unicam->node[i].dma_queue_lock);
> > > +			if (!list_empty(&unicam->node[i].dma_queue) &&
> > > +			    !unicam->node[i].next_frm)
> > > +				unicam_schedule_next_buffer(&unicam->node[i]);
> > > +			spin_unlock(&unicam->node[i].dma_queue_lock);
> > > +		}
> > > +	}
> > > +
> > > +	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > > +		/* Switch out of trigger mode if selected */
> > > +		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > +		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > > +	}
> > > +	return IRQ_HANDLED;
> > > +}
> > > +
> > > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > > +{
> > > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +	u32 pack, unpack;
> > > +	u32 val;
> > > +
> > > +	if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > > +		unpack = UNICAM_PUM_NONE;
> > > +		pack = UNICAM_PPM_NONE;
> > > +	} else {
> > > +		switch (node->fmtinfo->depth) {
> > > +		case 8:
> > > +			unpack = UNICAM_PUM_UNPACK8;
> > > +			break;
> > > +		case 10:
> > > +			unpack = UNICAM_PUM_UNPACK10;
> > > +			break;
> > > +		case 12:
> > > +			unpack = UNICAM_PUM_UNPACK12;
> > > +			break;
> > > +		case 14:
> > > +			unpack = UNICAM_PUM_UNPACK14;
> > > +			break;
> > > +		case 16:
> > > +			unpack = UNICAM_PUM_UNPACK16;
> > > +			break;
> > > +		default:
> > > +			unpack = UNICAM_PUM_NONE;
> > > +			break;
> > > +		}
> > > +
> > > +		/* Repacking is always to 16bpp */
> > > +		pack = UNICAM_PPM_PACK16;
> > 
> > Also 8-bit data?
> 
> Not that I know of. The 8-bit entries in unicam_image_formats have no
> .unpacked_fourcc field, so the condition in the if above will always be
> true for those as they can only be selected by setting the pixel format
> to fmtinfo->fourcc.
> 
> > > +	}
> > > +
> > > +	val = 0;
> > 
> > You could do initialisation in declaration.
> 
> Yes, but I think it's more readable to keep all the code that affects
> the 'val' variable together.
> 
> > > +	unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> > > +	unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> > > +	unicam_reg_write(unicam, UNICAM_IPIPE, val);
> > > +}
> > > +
> > > +static void unicam_cfg_image_id(struct unicam_device *unicam)
> > > +{
> > > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +
> > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +		/* CSI2 mode, hardcode VC 0 for now. */
> > > +		unicam_reg_write(unicam, UNICAM_IDI0,
> > > +				 (0 << 6) | node->fmtinfo->csi_dt);
> > > +	} else {
> > > +		/* CCP2 mode */
> > > +		unicam_reg_write(unicam, UNICAM_IDI0,
> > > +				 0x80 | node->fmtinfo->csi_dt);
> > > +	}
> > > +}
> > > +
> > > +static void unicam_enable_ed(struct unicam_device *unicam)
> > > +{
> > > +	u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> > > +
> > > +	unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> > > +	/* Do not wrap at the end of the embedded data buffer */
> > > +	unicam_set_field(&val, 0, UNICAM_DBOB);
> > > +
> > > +	unicam_reg_write(unicam, UNICAM_DCS, val);
> > > +}
> > > +
> > > +static void unicam_start_rx(struct unicam_device *unicam,
> > > +			    struct unicam_buffer *buf)
> > > +{
> > > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +	int line_int_freq = node->fmt.fmt.pix.height >> 2;
> > > +	unsigned int i;
> > > +	u32 val;
> > > +
> > > +	if (line_int_freq < 128)
> > > +		line_int_freq = 128;
> > 
> > 	line_int_freq = max(line_int_freq, 128);
> Ack.
> 
> > > +
> > > +	/* Enable lane clocks */
> > > +	val = 1;
> > 
> > Initialise in the loop initialisation below, I'd say.
> 
> How about
> 
> 	val = 0x55 & GENMASK(unicam->pipe.num_data_lanes * 2 - 1, 0);

I meant

 	val = 0x155 & GENMASK(unicam->pipe.num_data_lanes * 2 + 1, 0);

Maybe a comment would be useful ?

	/*
	 * Enable lane clocks. The register is structured as follows:
	 *
	 * [9:8] - DAT3
	 * [7:6] - DAT2
	 * [5:4] - DAT1
	 * [3:2] - DAT0
	 * [1:0] - CLK
	 *
	 * Enabled lane must be set to b01, and disabled lanes to b00. The clock
	 * lane is always enabled.
	 */
	val = 0x155 & GENMASK(unicam->pipe.num_data_lanes * 2 + 1, 0);

> > > +	for (i = 0; i < unicam->active_data_lanes; i++)
> > > +		val = val << 2 | 1;
> > > +	unicam_clk_write(unicam, val);
> > > +
> > > +	/* Basic init */
> > > +	unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> > > +
> > > +	/* Enable analogue control, and leave in reset. */
> > > +	val = UNICAM_AR;
> > > +	unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> > > +	unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> > > +	unicam_reg_write(unicam, UNICAM_ANA, val);
> > > +	usleep_range(1000, 2000);
> > > +
> > > +	/* Come out of reset */
> > > +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> > > +
> > > +	/* Peripheral reset */
> > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > > +
> > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > > +
> > > +	/* Enable Rx control. */
> > > +	val = unicam_reg_read(unicam, UNICAM_CTRL);
> > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +		unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> > > +		unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> > > +	} else {
> > > +		unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> > > +		unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> > > +	}
> > > +	/* Packet framer timeout */
> > > +	unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> > > +	unicam_set_field(&val, 128, UNICAM_OET_MASK);
> > > +	unicam_reg_write(unicam, UNICAM_CTRL, val);
> > > +
> > > +	unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> > > +	unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> > > +
> > > +	/* AXI bus access QoS setup */
> > > +	val = unicam_reg_read(unicam, UNICAM_PRI);
> > > +	unicam_set_field(&val, 0, UNICAM_BL_MASK);
> > > +	unicam_set_field(&val, 0, UNICAM_BS_MASK);
> > > +	unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> > > +	unicam_set_field(&val, 8, UNICAM_NP_MASK);
> > > +	unicam_set_field(&val, 2, UNICAM_PT_MASK);
> > > +	unicam_set_field(&val, 1, UNICAM_PE);
> > > +	unicam_reg_write(unicam, UNICAM_PRI, val);
> > > +
> > > +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> > > +
> > > +	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
> > > +	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> > > +	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> > > +	unicam_reg_write(unicam, UNICAM_ICTL, val);
> > > +	unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> > > +	unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> > > +
> > > +	/* tclk_term_en */
> > > +	unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> > > +	/* tclk_settle */
> > > +	unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> > > +	/* td_term_en */
> > > +	unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> > > +	/* ths_settle */
> > > +	unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> > > +	/* trx_enable */
> > > +	unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> > > +
> > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> > > +
> > > +	/* Packet compare setup - required to avoid missing frame ends */
> > > +	val = 0;
> > > +	unicam_set_field(&val, 1, UNICAM_PCE);
> > > +	unicam_set_field(&val, 1, UNICAM_GI);
> > > +	unicam_set_field(&val, 1, UNICAM_CPH);
> > > +	unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> > > +	unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> > > +	unicam_reg_write(unicam, UNICAM_CMP0, val);
> > > +
> > > +	/* Enable clock lane and set up terminations */
> > > +	val = 0;
> > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +		/* CSI2 */
> > > +		unicam_set_field(&val, 1, UNICAM_CLE);
> > > +		unicam_set_field(&val, 1, UNICAM_CLLPE);
> > > +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > > +			unicam_set_field(&val, 1, UNICAM_CLTRE);
> > > +			unicam_set_field(&val, 1, UNICAM_CLHSE);
> > > +		}
> > > +	} else {
> > > +		/* CCP2 */
> > > +		unicam_set_field(&val, 1, UNICAM_CLE);
> > > +		unicam_set_field(&val, 1, UNICAM_CLHSE);
> > > +		unicam_set_field(&val, 1, UNICAM_CLTRE);
> > > +	}
> > > +	unicam_reg_write(unicam, UNICAM_CLK, val);
> > > +
> > > +	/*
> > > +	 * Enable required data lanes with appropriate terminations.
> > > +	 * The same value needs to be written to UNICAM_DATn registers for
> > > +	 * the active lanes, and 0 for inactive ones.
> > > +	 */
> > > +	val = 0;
> > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > +		/* CSI2 */
> > > +		unicam_set_field(&val, 1, UNICAM_DLE);
> > > +		unicam_set_field(&val, 1, UNICAM_DLLPE);
> > > +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > > +			unicam_set_field(&val, 1, UNICAM_DLTRE);
> > > +			unicam_set_field(&val, 1, UNICAM_DLHSE);
> > > +		}
> > > +	} else {
> > > +		/* CCP2 */
> > > +		unicam_set_field(&val, 1, UNICAM_DLE);
> > > +		unicam_set_field(&val, 1, UNICAM_DLHSE);
> > > +		unicam_set_field(&val, 1, UNICAM_DLTRE);
> > > +	}
> > > +	unicam_reg_write(unicam, UNICAM_DAT0, val);
> > > +
> > > +	if (unicam->active_data_lanes == 1)
> > > +		val = 0;
> > > +	unicam_reg_write(unicam, UNICAM_DAT1, val);
> > > +
> > > +	if (unicam->max_data_lanes > 2) {
> > > +		/*
> > > +		 * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> > > +		 * instance supports more than 2 data lanes.
> > > +		 */
> > > +		if (unicam->active_data_lanes == 2)
> > > +			val = 0;
> > > +		unicam_reg_write(unicam, UNICAM_DAT2, val);
> > > +
> > > +		if (unicam->active_data_lanes == 3)
> > > +			val = 0;
> > > +		unicam_reg_write(unicam, UNICAM_DAT3, val);
> > > +	}
> > > +
> > > +	unicam_reg_write(unicam, UNICAM_IBLS,
> > > +			 node->fmt.fmt.pix.bytesperline);
> > > +	unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> > > +	unicam_set_packing_config(unicam);
> > > +	unicam_cfg_image_id(unicam);
> > > +
> > > +	val = unicam_reg_read(unicam, UNICAM_MISC);
> > > +	unicam_set_field(&val, 1, UNICAM_FL0);
> > > +	unicam_set_field(&val, 1, UNICAM_FL1);
> > > +	unicam_reg_write(unicam, UNICAM_MISC, val);
> > > +
> > > +	/* Enable peripheral */
> > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> > > +
> > > +	/* Load image pointers */
> > > +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> > > +
> > > +	/*
> > > +	 * Enable trigger only for the first frame to
> > > +	 * sync correctly to the FS from the source.
> > > +	 */
> > > +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > +}
> 
> [snip]
> 
> > > +static int unicam_async_nf_init(struct unicam_device *unicam)
> > > +{
> > > +	struct v4l2_fwnode_endpoint ep = { };
> > 
> > If the bus-type property is mandatory and you have no stated defaults
> > anywhere, this is fine. I.e. all the relevant properties would need to be
> > mandatory.
> 
> They are, as far as I can tell (well, the clock-noncontinuous property
> is not mandatory, but that's expected as it's a flag).
> 
> > > +	struct fwnode_handle *ep_handle;
> > > +	struct v4l2_async_connection *asc;
> > > +	int ret;
> > > +
> > > +	ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
> > > +				   &unicam->max_data_lanes);
> > > +	if (ret < 0) {
> > > +		dev_err(unicam->dev, "Missing %s DT property\n",
> > > +			"brcm,num-data-lanes");
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	/* Get and parse the local endpoint. */
> > > +	ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
> > > +						    FWNODE_GRAPH_ENDPOINT_NEXT);
> > > +	if (!ep_handle) {
> > > +		dev_err(unicam->dev, "No endpoint found\n");
> > > +		return -ENODEV;
> > > +	}
> > > +
> > > +	ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
> > > +	if (ret) {
> > > +		dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
> > > +		goto error;
> > > +	}
> > > +
> > > +	unicam->bus_type = ep.bus_type;
> > > +
> > > +	switch (ep.bus_type) {
> > > +	case V4L2_MBUS_CSI2_DPHY: {
> > > +		unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
> > > +
> > > +		if (num_data_lanes != 1 && num_data_lanes != 2 &&
> > > +		    num_data_lanes != 4) {
> > > +			dev_err(unicam->dev, "%u data lanes not supported\n",
> > > +				num_data_lanes);
> > > +			goto error;
> > > +		}
> > > +
> > > +		if (num_data_lanes > unicam->max_data_lanes) {
> > > +			dev_err(unicam->dev,
> > > +				"Endpoint uses %u data lanes when %u are supported\n",
> > > +				num_data_lanes, unicam->max_data_lanes);
> > > +			goto error;
> > > +		}
> > > +
> > > +		unicam->active_data_lanes = num_data_lanes;
> > > +		unicam->bus_flags = ep.bus.mipi_csi2.flags;
> > > +		break;
> > > +	}
> > > +
> > > +	case V4L2_MBUS_CCP2:
> > > +		unicam->max_data_lanes = 1;
> > > +		unicam->active_data_lanes = 1;
> > > +		unicam->bus_flags = ep.bus.mipi_csi1.strobe;
> > > +		break;
> > > +
> > > +	default:
> > > +		/* Unsupported bus type */
> > > +		dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
> > > +		goto error;
> > > +	}
> > > +
> > > +	/* Initialize and register the async notifier. */
> > > +	v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
> > > +
> > > +	asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
> > > +					      struct v4l2_async_connection);
> > > +	fwnode_handle_put(ep_handle);
> > > +	ep_handle = NULL;
> > > +
> > > +	if (IS_ERR(asc)) {
> > > +		ret = PTR_ERR(asc);
> > > +		dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
> > > +			ret);
> > > +		goto error;
> > > +	}
> > > +
> > > +	unicam->notifier.ops = &unicam_async_ops;
> > > +
> > > +	ret = v4l2_async_nf_register(&unicam->notifier);
> > > +	if (ret) {
> > > +		dev_err(unicam->dev, "Error registering device notifier: %d\n",
> > > +			ret);
> > > +		goto error;
> > > +	}
> > > +
> > > +	return 0;
> > > +
> > > +error:
> > > +	fwnode_handle_put(ep_handle);
> > > +	return ret;
> > > +}
> > > +
> > > +/* -----------------------------------------------------------------------------
> > > + * Probe & remove
> > > + */
> > > +
> > > +static int unicam_media_init(struct unicam_device *unicam)
> > > +{
> > > +	int ret;
> > > +
> > > +	unicam->mdev.dev = unicam->dev;
> > > +	strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
> > > +		sizeof(unicam->mdev.model));
> > > +	strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));
> > 
> > Isn't the field already zeroed?
> 
> Indeed. I'll drop this.
> 
> > 
> > > +	unicam->mdev.hw_revision = 0;
> > > +
> > > +	media_device_init(&unicam->mdev);
> > > +
> > > +	unicam->v4l2_dev.mdev = &unicam->mdev;
> > > +
> > > +	ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
> > > +	if (ret < 0) {
> > > +		dev_err(unicam->dev, "Unable to register v4l2 device\n");
> > > +		goto err_media_cleanup;
> > > +	}
> > > +
> > > +	ret = media_device_register(&unicam->mdev);
> > > +	if (ret < 0) {
> > > +		dev_err(unicam->dev,
> > > +			"Unable to register media-controller device\n");
> > > +		goto err_v4l2_unregister;
> > > +	}
> > > +
> > > +	return 0;
> > > +
> > > +err_v4l2_unregister:
> > > +	v4l2_device_unregister(&unicam->v4l2_dev);
> > > +err_media_cleanup:
> > > +	media_device_cleanup(&unicam->mdev);
> > > +	return ret;
> > > +}
> 
> [snip]

Dave Stevenson March 26, 2024, 3:23 p.m. UTC | #13

Hi Sakari & Laurent

On Tue, 26 Mar 2024 at 01:37, Laurent Pinchart
<[e-mail]> wrote:
>
> Hi Sakari,
>
> On Mon, Mar 25, 2024 at 06:36:49PM +0000, Sakari Ailus wrote:
> > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > From: Dave Stevenson <[e-mail]>
> > >
> > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > It is represented as two video device nodes: unicam-image and
> > > unicam-embedded which are connected to an internal subdev (named
> > > unicam-subdev) in order to manage streams routing.
> > >
> > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > Signed-off-by: Laurent Pinchart <[e-mail]>
> >
> > Thanks for submitting this, it's the cleanest and neatest Unicom driver
>
> Unicam, or if you insist Unicorn, but not Unicom :-)
>
> > I've ever seen!
> >
> > Some mostly unimportant comments below, however the bus-type issue needs to
> > be addressed.
> >
> > > ---
> > > Changes since v5:
> > >
> > > - Move to drivers/media/platform/broadcom/
> > > - Port to the upstream V4L2 streams API
> > > - Rebase on latest metadata API proposal
> > > - Add missing error message
> > > - Drop unneeded documentation block for unicam_isr()
> > > - Drop unneeded dev_dbg() and dev_err() messages
> > > - Drop unneeded streams_mask and fmt checks
> > > - Drop unused unicam_sd_pad_is_sink()
> > > - Drop unneeded includes
> > > - Drop v4l2_ctrl_subscribe_event() call
> > > - Use pm_runtime_resume_and_get()
> > > - Indentation and line wrap fixes
> > > - Let the framework set bus_info
> > > - Use v4l2_fwnode_endpoint_parse()
> > > - Fix media device cleanup
> > > - Drop lane reordering checks
> > > - Fix subdev state locking
> > > - Drop extra debug messages
> > > - Move clock handling to runtime PM handlers
> > > - Reorder functions
> > > - Rename init functions for more clarity
> > > - Initialize runtime PM earlier
> > > - Clarify error messages
> > > - Simplify subdev init with local variable
> > > - Fix subdev cleanup
> > > - Fix typos and indentation
> > > - Don't initialize local variables needlessly
> > > - Simplify num lanes check
> > > - Fix metadata handling in subdev set_fmt
> > > - Drop manual fallback to .s_stream()
> > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > - Simplify unicam_set_default_format()
> > > - Fix default format settings
> > > - Add busy check in unicam_s_fmt_meta()
> > > - Add missing \n at end of format strings
> > > - Fix metadata handling in subdev set_fmt
> > > - Fix locking when starting streaming
> > > - Return buffers from start streaming fails
> > > - Fix format validation for metadata node
> > > - Use video_device_pipeline_{start,stop}() helpers
> > > - Simplify format enumeration
> > > - Drop unset variable
> > > - Update MAINTAINERS entry
> > > - Update to the upstream v4l2_async_nf API
> > > - Update to the latest subdev routing API
> > > - Update to the latest subdev state API
> > > - Move from subdev .init_cfg() to .init_state()
> > > - Update to the latest videobuf2 API
> > > - Fix v4l2_subdev_enable_streams() error check
> > > - Use correct pad for the connected subdev
> > > - Return buffers to vb2 when start streaming fails
> > > - Improve debugging in start streaming handler
> > > - Simplify DMA address management
> > > - Drop comment about bcm2835-camera driver
> > > - Clarify comments that explain min/max sizes
> > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > - Drop unneeded local variables
> > > - Rename image-related constants and functions
> > > - Turn unicam_fmt.metadata_fmt into bool
> > > - Rename unicam_fmt to unicam_format_info
> > > - Rename unicam_format_info variables to fmtinfo
> > > - Rename unicam_node.v_fmt to fmt
> > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > - Make metadata formats line-based
> > > - Validate format on metadata video device
> > > - Add Co-devlopped-by tags
> > >
> > > Changes since v3:
> > >
> > > - Add the vendor prefix for DT name
> > > - Use the reg-names in DT parsing
> > > - Remove MAINTAINERS entry
> > >
> > > Changes since v2:
> > >
> > > - Change code organization
> > > - Remove unused variables
> > > - Correct the fmt_meta functions
> > > - Rewrite the start/stop streaming
> > >   - You can now start the image node alone, but not the metadata one
> > >   - The buffers are allocated per-node
> > >   - only the required stream is started, if the route exists and is
> > >     enabled
> > > - Prefix the macros with UNICAM_ to not have too generic names
> > > - Drop colorspace support
> > >
> > > Changes since v1:
> > >
> > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > ---
> > >  MAINTAINERS                                   |    1 +
> > >  drivers/media/platform/Kconfig                |    1 +
> > >  drivers/media/platform/Makefile               |    1 +
> > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > >  7 files changed, 2891 insertions(+)
> > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index e50a59654e6e..cc350729f467 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -4002,6 +4002,7 @@ M:    Raspberry Pi Kernel Maintenance <[e-mail]>
> > >  L: [e-mail]
> > >  S: Maintained
> > >  F: Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > > +F: drivers/media/platform/bcm2835/
> > >
> > >  BROADCOM BCM47XX MIPS ARCHITECTURE
> > >  M: Hauke Mehrtens <[e-mail]>
> > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > index 91e54215de3a..2d79bfc68c15 100644
> > > --- a/drivers/media/platform/Kconfig
> > > +++ b/drivers/media/platform/Kconfig
> > > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> > >  source "drivers/media/platform/amphion/Kconfig"
> > >  source "drivers/media/platform/aspeed/Kconfig"
> > >  source "drivers/media/platform/atmel/Kconfig"
> > > +source "drivers/media/platform/broadcom/Kconfig"
> > >  source "drivers/media/platform/cadence/Kconfig"
> > >  source "drivers/media/platform/chips-media/Kconfig"
> > >  source "drivers/media/platform/intel/Kconfig"
> > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > > index 3296ec1ebe16..da17301f7439 100644
> > > --- a/drivers/media/platform/Makefile
> > > +++ b/drivers/media/platform/Makefile
> > > @@ -10,6 +10,7 @@ obj-y += amlogic/
> > >  obj-y += amphion/
> > >  obj-y += aspeed/
> > >  obj-y += atmel/
> > > +obj-y += broadcom/
> > >  obj-y += cadence/
> > >  obj-y += chips-media/
> > >  obj-y += intel/
> > > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > > new file mode 100644
> > > index 000000000000..cc2c9afcc948
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/Kconfig
> > > @@ -0,0 +1,23 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +config VIDEO_BCM2835_UNICAM
> > > +   tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > > +   depends on ARCH_BCM2835 || COMPILE_TEST
> > > +   depends on PM
> > > +   depends on VIDEO_DEV
> > > +   select MEDIA_CONTROLLER
> > > +   select V4L2_FWNODE
> > > +   select VIDEO_V4L2_SUBDEV_API
> > > +   select VIDEOBUF2_DMA_CONTIG
> > > +   help
> > > +     Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > > +     This is a V4L2 driver that controls the CSI-2 receiver directly,
> > > +     independently from the VC4 firmware.
> > > +
> > > +     This driver is mutually exclusive with the use of bcm2835-camera. The
> > > +     firmware will disable all access to the peripheral from within the
> > > +     firmware if it finds a DT node using it, and bcm2835-camera will
> > > +     therefore fail to probe.
> > > +
> > > +     To compile this driver as a module, choose M here. The module will be
> > > +     called bcm2835-unicam.
> > > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > > new file mode 100644
> > > index 000000000000..03d2045aba2e
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/Makefile
> > > @@ -0,0 +1,3 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > new file mode 100644
> > > index 000000000000..84775fd2fac5
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > @@ -0,0 +1,255 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > +
> > > +/*
> > > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> >
> > Anything up to 2024?
>
> Not really. The registers haven't really changed :-) I'll update the
> copyright in the .c file though.
>
> > > + * Dave Stevenson <[e-mail]>
> > > + */
>
> [snip]
>
> > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > new file mode 100644
> > > index 000000000000..716c89b8a217
> > > --- /dev/null
> > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > @@ -0,0 +1,2607 @@
>
> [snip]
>
> > > +static irqreturn_t unicam_isr(int irq, void *dev)
> > > +{
> > > +   struct unicam_device *unicam = dev;
> > > +   unsigned int lines_done = unicam_get_lines_done(dev);
> > > +   unsigned int sequence = unicam->sequence;
> > > +   unsigned int i;
> > > +   u32 ista, sta;
> > > +   bool fe;
> > > +   u64 ts;
> > > +
> > > +   sta = unicam_reg_read(unicam, UNICAM_STA);
> > > +   /* Write value back to clear the interrupts */
> > > +   unicam_reg_write(unicam, UNICAM_STA, sta);
> > > +
> > > +   ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > > +   /* Write value back to clear the interrupts */
> > > +   unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > > +
> > > +   dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > > +           ista, sta, sequence, lines_done);
> > > +
> > > +   if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > > +           return IRQ_HANDLED;
> > > +
> > > +   /*
> > > +    * Look for either the Frame End interrupt or the Packet Capture status
> > > +    * to signal a frame end.
> > > +    */
> > > +   fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > > +
> > > +   /*
> > > +    * We must run the frame end handler first. If we have a valid next_frm
> > > +    * and we get a simultaneout FE + FS interrupt, running the FS handler
> > > +    * first would null out the next_frm ptr and we would have lost the
> > > +    * buffer forever.
> > > +    */
> > > +   if (fe) {
> > > +           /*
> > > +            * Ensure we have swapped buffers already as we can't
> > > +            * stop the peripheral. If no buffer is available, use a
> > > +            * dummy buffer to dump out frames until we get a new buffer
> > > +            * to use.
> > > +            */
> > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +                   if (!unicam->node[i].streaming)
> > > +                           continue;
> > > +
> > > +                   /*
> > > +                    * If cur_frm == next_frm, it means we have not had
> > > +                    * a chance to swap buffers, likely due to having
> > > +                    * multiple interrupts occurring simultaneously (like FE
> > > +                    * + FS + LS). In this case, we cannot signal the buffer
> > > +                    * as complete, as the HW will reuse that buffer.
> > > +                    */
> > > +                   if (unicam->node[i].cur_frm &&
> > > +                       unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > > +                           unicam_process_buffer_complete(&unicam->node[i],
> > > +                                                          sequence);
> > > +                   unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > > +           }
> > > +           unicam->sequence++;
> >
> > Does access to this data need to be serialised somehow.
>
> Given that it's only accessed from the interrupt handler (beside
> start_streaming time, before starting the hardware), I don't think so.
>
> > > +   }
> > > +
> > > +   if (ista & UNICAM_FSI) {
> > > +           /*
> > > +            * Timestamp is to be when the first data byte was captured,
> > > +            * aka frame start.
> > > +            */
> > > +           ts = ktime_get_ns();
> > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +                   if (!unicam->node[i].streaming)
> > > +                           continue;
> > > +
> > > +                   if (unicam->node[i].cur_frm)
> > > +                           unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > > +                                                           ts;
> > > +                   else
> > > +                           dev_dbg(unicam->v4l2_dev.dev,
> > > +                                   "ISR: [%d] Dropping frame, buffer not available at FS\n",
> > > +                                   i);
> > > +                   /*
> > > +                    * Set the next frame output to go to a dummy frame
> > > +                    * if we have not managed to obtain another frame
> > > +                    * from the queue.
> > > +                    */
> > > +                   unicam_schedule_dummy_buffer(&unicam->node[i]);
> > > +           }
> > > +
> > > +           unicam_queue_event_sof(unicam);
> > > +   }
> > > +
> > > +   /*
> > > +    * Cannot swap buffer at frame end, there may be a race condition
> > > +    * where the HW does not actually swap it if the new frame has
> > > +    * already started.
> > > +    */
> > > +   if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > +                   if (!unicam->node[i].streaming)
> > > +                           continue;
> > > +
> > > +                   spin_lock(&unicam->node[i].dma_queue_lock);
> > > +                   if (!list_empty(&unicam->node[i].dma_queue) &&
> > > +                       !unicam->node[i].next_frm)
> > > +                           unicam_schedule_next_buffer(&unicam->node[i]);
> > > +                   spin_unlock(&unicam->node[i].dma_queue_lock);
> > > +           }
> > > +   }
> > > +
> > > +   if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > > +           /* Switch out of trigger mode if selected */
> > > +           unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > +           unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > > +   }
> > > +   return IRQ_HANDLED;
> > > +}
> > > +
> > > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > > +{
> > > +   struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > +   u32 pack, unpack;
> > > +   u32 val;
> > > +
> > > +   if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > > +           unpack = UNICAM_PUM_NONE;
> > > +           pack = UNICAM_PPM_NONE;
> > > +   } else {
> > > +           switch (node->fmtinfo->depth) {
> > > +           case 8:
> > > +                   unpack = UNICAM_PUM_UNPACK8;
> > > +                   break;
> > > +           case 10:
> > > +                   unpack = UNICAM_PUM_UNPACK10;
> > > +                   break;
> > > +           case 12:
> > > +                   unpack = UNICAM_PUM_UNPACK12;
> > > +                   break;
> > > +           case 14:
> > > +                   unpack = UNICAM_PUM_UNPACK14;
> > > +                   break;
> > > +           case 16:
> > > +                   unpack = UNICAM_PUM_UNPACK16;
> > > +                   break;
> > > +           default:
> > > +                   unpack = UNICAM_PUM_NONE;
> > > +                   break;
> > > +           }
> > > +
> > > +           /* Repacking is always to 16bpp */
> > > +           pack = UNICAM_PPM_PACK16;
> >
> > Also 8-bit data?
>
> Not that I know of. The 8-bit entries in unicam_image_formats have no
> .unpacked_fourcc field, so the condition in the if above will always be
> true for those as they can only be selected by setting the pixel format
> to fmtinfo->fourcc.

Correct.
The unpacking / packing doesn't bit shift, hence 10P can be unpacked
to 10, 12P to 12, and 14P to 14, but there is no 8bit unpacked into
the LSBs of 16 bit words defined as a V4L2 format.

You can configure packing to produce 10P, 12P, etc, but without the
bitshift it has no real use.

MSBs get dropped if you try packing to a smaller bit depth than the
source, so packing to 8 bit from any other depth results in unusable
output.

If being really critical, then there is no point in having the case 8
and case 16 in this switch as they will never be selected.

  Dave

> > > +   }
<snip>

Laurent Pinchart March 26, 2024, 4:42 p.m. UTC | #14

Hi Dave,

On Tue, Mar 26, 2024 at 03:23:42PM +0000, Dave Stevenson wrote:
> On Tue, 26 Mar 2024 at 01:37, Laurent Pinchart wrote:
> > On Mon, Mar 25, 2024 at 06:36:49PM +0000, Sakari Ailus wrote:
> > > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > > From: Dave Stevenson <[e-mail]>
> > > >
> > > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > > It is represented as two video device nodes: unicam-image and
> > > > unicam-embedded which are connected to an internal subdev (named
> > > > unicam-subdev) in order to manage streams routing.
> > > >
> > > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > >
> > > Thanks for submitting this, it's the cleanest and neatest Unicom driver
> >
> > Unicam, or if you insist Unicorn, but not Unicom :-)
> >
> > > I've ever seen!
> > >
> > > Some mostly unimportant comments below, however the bus-type issue needs to
> > > be addressed.
> > >
> > > > ---
> > > > Changes since v5:
> > > >
> > > > - Move to drivers/media/platform/broadcom/
> > > > - Port to the upstream V4L2 streams API
> > > > - Rebase on latest metadata API proposal
> > > > - Add missing error message
> > > > - Drop unneeded documentation block for unicam_isr()
> > > > - Drop unneeded dev_dbg() and dev_err() messages
> > > > - Drop unneeded streams_mask and fmt checks
> > > > - Drop unused unicam_sd_pad_is_sink()
> > > > - Drop unneeded includes
> > > > - Drop v4l2_ctrl_subscribe_event() call
> > > > - Use pm_runtime_resume_and_get()
> > > > - Indentation and line wrap fixes
> > > > - Let the framework set bus_info
> > > > - Use v4l2_fwnode_endpoint_parse()
> > > > - Fix media device cleanup
> > > > - Drop lane reordering checks
> > > > - Fix subdev state locking
> > > > - Drop extra debug messages
> > > > - Move clock handling to runtime PM handlers
> > > > - Reorder functions
> > > > - Rename init functions for more clarity
> > > > - Initialize runtime PM earlier
> > > > - Clarify error messages
> > > > - Simplify subdev init with local variable
> > > > - Fix subdev cleanup
> > > > - Fix typos and indentation
> > > > - Don't initialize local variables needlessly
> > > > - Simplify num lanes check
> > > > - Fix metadata handling in subdev set_fmt
> > > > - Drop manual fallback to .s_stream()
> > > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > > - Simplify unicam_set_default_format()
> > > > - Fix default format settings
> > > > - Add busy check in unicam_s_fmt_meta()
> > > > - Add missing \n at end of format strings
> > > > - Fix metadata handling in subdev set_fmt
> > > > - Fix locking when starting streaming
> > > > - Return buffers from start streaming fails
> > > > - Fix format validation for metadata node
> > > > - Use video_device_pipeline_{start,stop}() helpers
> > > > - Simplify format enumeration
> > > > - Drop unset variable
> > > > - Update MAINTAINERS entry
> > > > - Update to the upstream v4l2_async_nf API
> > > > - Update to the latest subdev routing API
> > > > - Update to the latest subdev state API
> > > > - Move from subdev .init_cfg() to .init_state()
> > > > - Update to the latest videobuf2 API
> > > > - Fix v4l2_subdev_enable_streams() error check
> > > > - Use correct pad for the connected subdev
> > > > - Return buffers to vb2 when start streaming fails
> > > > - Improve debugging in start streaming handler
> > > > - Simplify DMA address management
> > > > - Drop comment about bcm2835-camera driver
> > > > - Clarify comments that explain min/max sizes
> > > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > > - Drop unneeded local variables
> > > > - Rename image-related constants and functions
> > > > - Turn unicam_fmt.metadata_fmt into bool
> > > > - Rename unicam_fmt to unicam_format_info
> > > > - Rename unicam_format_info variables to fmtinfo
> > > > - Rename unicam_node.v_fmt to fmt
> > > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > > - Make metadata formats line-based
> > > > - Validate format on metadata video device
> > > > - Add Co-devlopped-by tags
> > > >
> > > > Changes since v3:
> > > >
> > > > - Add the vendor prefix for DT name
> > > > - Use the reg-names in DT parsing
> > > > - Remove MAINTAINERS entry
> > > >
> > > > Changes since v2:
> > > >
> > > > - Change code organization
> > > > - Remove unused variables
> > > > - Correct the fmt_meta functions
> > > > - Rewrite the start/stop streaming
> > > >   - You can now start the image node alone, but not the metadata one
> > > >   - The buffers are allocated per-node
> > > >   - only the required stream is started, if the route exists and is
> > > >     enabled
> > > > - Prefix the macros with UNICAM_ to not have too generic names
> > > > - Drop colorspace support
> > > >
> > > > Changes since v1:
> > > >
> > > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > > ---
> > > >  MAINTAINERS                                   |    1 +
> > > >  drivers/media/platform/Kconfig                |    1 +
> > > >  drivers/media/platform/Makefile               |    1 +
> > > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > > >  7 files changed, 2891 insertions(+)
> > > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > > >
> > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > index e50a59654e6e..cc350729f467 100644
> > > > --- a/MAINTAINERS
> > > > +++ b/MAINTAINERS
> > > > @@ -4002,6 +4002,7 @@ M:    Raspberry Pi Kernel Maintenance <[e-mail]>
> > > >  L: [e-mail]
> > > >  S: Maintained
> > > >  F: Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > > > +F: drivers/media/platform/bcm2835/
> > > >
> > > >  BROADCOM BCM47XX MIPS ARCHITECTURE
> > > >  M: Hauke Mehrtens <[e-mail]>
> > > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > > index 91e54215de3a..2d79bfc68c15 100644
> > > > --- a/drivers/media/platform/Kconfig
> > > > +++ b/drivers/media/platform/Kconfig
> > > > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> > > >  source "drivers/media/platform/amphion/Kconfig"
> > > >  source "drivers/media/platform/aspeed/Kconfig"
> > > >  source "drivers/media/platform/atmel/Kconfig"
> > > > +source "drivers/media/platform/broadcom/Kconfig"
> > > >  source "drivers/media/platform/cadence/Kconfig"
> > > >  source "drivers/media/platform/chips-media/Kconfig"
> > > >  source "drivers/media/platform/intel/Kconfig"
> > > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > > > index 3296ec1ebe16..da17301f7439 100644
> > > > --- a/drivers/media/platform/Makefile
> > > > +++ b/drivers/media/platform/Makefile
> > > > @@ -10,6 +10,7 @@ obj-y += amlogic/
> > > >  obj-y += amphion/
> > > >  obj-y += aspeed/
> > > >  obj-y += atmel/
> > > > +obj-y += broadcom/
> > > >  obj-y += cadence/
> > > >  obj-y += chips-media/
> > > >  obj-y += intel/
> > > > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > > > new file mode 100644
> > > > index 000000000000..cc2c9afcc948
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/Kconfig
> > > > @@ -0,0 +1,23 @@
> > > > +# SPDX-License-Identifier: GPL-2.0
> > > > +
> > > > +config VIDEO_BCM2835_UNICAM
> > > > +   tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > > > +   depends on ARCH_BCM2835 || COMPILE_TEST
> > > > +   depends on PM
> > > > +   depends on VIDEO_DEV
> > > > +   select MEDIA_CONTROLLER
> > > > +   select V4L2_FWNODE
> > > > +   select VIDEO_V4L2_SUBDEV_API
> > > > +   select VIDEOBUF2_DMA_CONTIG
> > > > +   help
> > > > +     Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > > > +     This is a V4L2 driver that controls the CSI-2 receiver directly,
> > > > +     independently from the VC4 firmware.
> > > > +
> > > > +     This driver is mutually exclusive with the use of bcm2835-camera. The
> > > > +     firmware will disable all access to the peripheral from within the
> > > > +     firmware if it finds a DT node using it, and bcm2835-camera will
> > > > +     therefore fail to probe.
> > > > +
> > > > +     To compile this driver as a module, choose M here. The module will be
> > > > +     called bcm2835-unicam.
> > > > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > > > new file mode 100644
> > > > index 000000000000..03d2045aba2e
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/Makefile
> > > > @@ -0,0 +1,3 @@
> > > > +# SPDX-License-Identifier: GPL-2.0
> > > > +
> > > > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > new file mode 100644
> > > > index 000000000000..84775fd2fac5
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > @@ -0,0 +1,255 @@
> > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > +
> > > > +/*
> > > > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> > >
> > > Anything up to 2024?
> >
> > Not really. The registers haven't really changed :-) I'll update the
> > copyright in the .c file though.
> >
> > > > + * Dave Stevenson <[e-mail]>
> > > > + */
> >
> > [snip]
> >
> > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > new file mode 100644
> > > > index 000000000000..716c89b8a217
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > @@ -0,0 +1,2607 @@
> >
> > [snip]
> >
> > > > +static irqreturn_t unicam_isr(int irq, void *dev)
> > > > +{
> > > > +   struct unicam_device *unicam = dev;
> > > > +   unsigned int lines_done = unicam_get_lines_done(dev);
> > > > +   unsigned int sequence = unicam->sequence;
> > > > +   unsigned int i;
> > > > +   u32 ista, sta;
> > > > +   bool fe;
> > > > +   u64 ts;
> > > > +
> > > > +   sta = unicam_reg_read(unicam, UNICAM_STA);
> > > > +   /* Write value back to clear the interrupts */
> > > > +   unicam_reg_write(unicam, UNICAM_STA, sta);
> > > > +
> > > > +   ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > > > +   /* Write value back to clear the interrupts */
> > > > +   unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > > > +
> > > > +   dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > > > +           ista, sta, sequence, lines_done);
> > > > +
> > > > +   if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > > > +           return IRQ_HANDLED;
> > > > +
> > > > +   /*
> > > > +    * Look for either the Frame End interrupt or the Packet Capture status
> > > > +    * to signal a frame end.
> > > > +    */
> > > > +   fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > > > +
> > > > +   /*
> > > > +    * We must run the frame end handler first. If we have a valid next_frm
> > > > +    * and we get a simultaneout FE + FS interrupt, running the FS handler
> > > > +    * first would null out the next_frm ptr and we would have lost the
> > > > +    * buffer forever.
> > > > +    */
> > > > +   if (fe) {
> > > > +           /*
> > > > +            * Ensure we have swapped buffers already as we can't
> > > > +            * stop the peripheral. If no buffer is available, use a
> > > > +            * dummy buffer to dump out frames until we get a new buffer
> > > > +            * to use.
> > > > +            */
> > > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > +                   if (!unicam->node[i].streaming)
> > > > +                           continue;
> > > > +
> > > > +                   /*
> > > > +                    * If cur_frm == next_frm, it means we have not had
> > > > +                    * a chance to swap buffers, likely due to having
> > > > +                    * multiple interrupts occurring simultaneously (like FE
> > > > +                    * + FS + LS). In this case, we cannot signal the buffer
> > > > +                    * as complete, as the HW will reuse that buffer.
> > > > +                    */
> > > > +                   if (unicam->node[i].cur_frm &&
> > > > +                       unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > > > +                           unicam_process_buffer_complete(&unicam->node[i],
> > > > +                                                          sequence);
> > > > +                   unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > > > +           }
> > > > +           unicam->sequence++;
> > >
> > > Does access to this data need to be serialised somehow.
> >
> > Given that it's only accessed from the interrupt handler (beside
> > start_streaming time, before starting the hardware), I don't think so.
> >
> > > > +   }
> > > > +
> > > > +   if (ista & UNICAM_FSI) {
> > > > +           /*
> > > > +            * Timestamp is to be when the first data byte was captured,
> > > > +            * aka frame start.
> > > > +            */
> > > > +           ts = ktime_get_ns();
> > > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > +                   if (!unicam->node[i].streaming)
> > > > +                           continue;
> > > > +
> > > > +                   if (unicam->node[i].cur_frm)
> > > > +                           unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > > > +                                                           ts;
> > > > +                   else
> > > > +                           dev_dbg(unicam->v4l2_dev.dev,
> > > > +                                   "ISR: [%d] Dropping frame, buffer not available at FS\n",
> > > > +                                   i);
> > > > +                   /*
> > > > +                    * Set the next frame output to go to a dummy frame
> > > > +                    * if we have not managed to obtain another frame
> > > > +                    * from the queue.
> > > > +                    */
> > > > +                   unicam_schedule_dummy_buffer(&unicam->node[i]);
> > > > +           }
> > > > +
> > > > +           unicam_queue_event_sof(unicam);
> > > > +   }
> > > > +
> > > > +   /*
> > > > +    * Cannot swap buffer at frame end, there may be a race condition
> > > > +    * where the HW does not actually swap it if the new frame has
> > > > +    * already started.
> > > > +    */
> > > > +   if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > +                   if (!unicam->node[i].streaming)
> > > > +                           continue;
> > > > +
> > > > +                   spin_lock(&unicam->node[i].dma_queue_lock);
> > > > +                   if (!list_empty(&unicam->node[i].dma_queue) &&
> > > > +                       !unicam->node[i].next_frm)
> > > > +                           unicam_schedule_next_buffer(&unicam->node[i]);
> > > > +                   spin_unlock(&unicam->node[i].dma_queue_lock);
> > > > +           }
> > > > +   }
> > > > +
> > > > +   if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > > > +           /* Switch out of trigger mode if selected */
> > > > +           unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > > +           unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > > > +   }
> > > > +   return IRQ_HANDLED;
> > > > +}
> > > > +
> > > > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > > > +{
> > > > +   struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > > +   u32 pack, unpack;
> > > > +   u32 val;
> > > > +
> > > > +   if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > > > +           unpack = UNICAM_PUM_NONE;
> > > > +           pack = UNICAM_PPM_NONE;
> > > > +   } else {
> > > > +           switch (node->fmtinfo->depth) {
> > > > +           case 8:
> > > > +                   unpack = UNICAM_PUM_UNPACK8;
> > > > +                   break;
> > > > +           case 10:
> > > > +                   unpack = UNICAM_PUM_UNPACK10;
> > > > +                   break;
> > > > +           case 12:
> > > > +                   unpack = UNICAM_PUM_UNPACK12;
> > > > +                   break;
> > > > +           case 14:
> > > > +                   unpack = UNICAM_PUM_UNPACK14;
> > > > +                   break;
> > > > +           case 16:
> > > > +                   unpack = UNICAM_PUM_UNPACK16;
> > > > +                   break;
> > > > +           default:
> > > > +                   unpack = UNICAM_PUM_NONE;
> > > > +                   break;
> > > > +           }
> > > > +
> > > > +           /* Repacking is always to 16bpp */
> > > > +           pack = UNICAM_PPM_PACK16;
> > >
> > > Also 8-bit data?
> >
> > Not that I know of. The 8-bit entries in unicam_image_formats have no
> > .unpacked_fourcc field, so the condition in the if above will always be
> > true for those as they can only be selected by setting the pixel format
> > to fmtinfo->fourcc.
> 
> Correct.
> The unpacking / packing doesn't bit shift, hence 10P can be unpacked
> to 10, 12P to 12, and 14P to 14, but there is no 8bit unpacked into
> the LSBs of 16 bit words defined as a V4L2 format.
> 
> You can configure packing to produce 10P, 12P, etc, but without the
> bitshift it has no real use.
> 
> MSBs get dropped if you try packing to a smaller bit depth than the
> source, so packing to 8 bit from any other depth results in unusable
> output.
> 
> If being really critical, then there is no point in having the case 8
> and case 16 in this switch as they will never be selected.

As we have space to spare in the unicam_format_info structure due to
padding, I'll move the unpack value there and drop the switch.

> > > > +   }
>
> <snip>

Dave Stevenson March 26, 2024, 5:01 p.m. UTC | #15

On Tue, 26 Mar 2024 at 16:42, Laurent Pinchart
<[e-mail]> wrote:
>
> Hi Dave,
>
> On Tue, Mar 26, 2024 at 03:23:42PM +0000, Dave Stevenson wrote:
> > On Tue, 26 Mar 2024 at 01:37, Laurent Pinchart wrote:
> > > On Mon, Mar 25, 2024 at 06:36:49PM +0000, Sakari Ailus wrote:
> > > > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > > > From: Dave Stevenson <[e-mail]>
> > > > >
> > > > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > > > It is represented as two video device nodes: unicam-image and
> > > > > unicam-embedded which are connected to an internal subdev (named
> > > > > unicam-subdev) in order to manage streams routing.
> > > > >
> > > > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > > >
> > > > Thanks for submitting this, it's the cleanest and neatest Unicom driver
> > >
> > > Unicam, or if you insist Unicorn, but not Unicom :-)
> > >
> > > > I've ever seen!
> > > >
> > > > Some mostly unimportant comments below, however the bus-type issue needs to
> > > > be addressed.
> > > >
> > > > > ---
> > > > > Changes since v5:
> > > > >
> > > > > - Move to drivers/media/platform/broadcom/
> > > > > - Port to the upstream V4L2 streams API
> > > > > - Rebase on latest metadata API proposal
> > > > > - Add missing error message
> > > > > - Drop unneeded documentation block for unicam_isr()
> > > > > - Drop unneeded dev_dbg() and dev_err() messages
> > > > > - Drop unneeded streams_mask and fmt checks
> > > > > - Drop unused unicam_sd_pad_is_sink()
> > > > > - Drop unneeded includes
> > > > > - Drop v4l2_ctrl_subscribe_event() call
> > > > > - Use pm_runtime_resume_and_get()
> > > > > - Indentation and line wrap fixes
> > > > > - Let the framework set bus_info
> > > > > - Use v4l2_fwnode_endpoint_parse()
> > > > > - Fix media device cleanup
> > > > > - Drop lane reordering checks
> > > > > - Fix subdev state locking
> > > > > - Drop extra debug messages
> > > > > - Move clock handling to runtime PM handlers
> > > > > - Reorder functions
> > > > > - Rename init functions for more clarity
> > > > > - Initialize runtime PM earlier
> > > > > - Clarify error messages
> > > > > - Simplify subdev init with local variable
> > > > > - Fix subdev cleanup
> > > > > - Fix typos and indentation
> > > > > - Don't initialize local variables needlessly
> > > > > - Simplify num lanes check
> > > > > - Fix metadata handling in subdev set_fmt
> > > > > - Drop manual fallback to .s_stream()
> > > > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > > > - Simplify unicam_set_default_format()
> > > > > - Fix default format settings
> > > > > - Add busy check in unicam_s_fmt_meta()
> > > > > - Add missing \n at end of format strings
> > > > > - Fix metadata handling in subdev set_fmt
> > > > > - Fix locking when starting streaming
> > > > > - Return buffers from start streaming fails
> > > > > - Fix format validation for metadata node
> > > > > - Use video_device_pipeline_{start,stop}() helpers
> > > > > - Simplify format enumeration
> > > > > - Drop unset variable
> > > > > - Update MAINTAINERS entry
> > > > > - Update to the upstream v4l2_async_nf API
> > > > > - Update to the latest subdev routing API
> > > > > - Update to the latest subdev state API
> > > > > - Move from subdev .init_cfg() to .init_state()
> > > > > - Update to the latest videobuf2 API
> > > > > - Fix v4l2_subdev_enable_streams() error check
> > > > > - Use correct pad for the connected subdev
> > > > > - Return buffers to vb2 when start streaming fails
> > > > > - Improve debugging in start streaming handler
> > > > > - Simplify DMA address management
> > > > > - Drop comment about bcm2835-camera driver
> > > > > - Clarify comments that explain min/max sizes
> > > > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > > > - Drop unneeded local variables
> > > > > - Rename image-related constants and functions
> > > > > - Turn unicam_fmt.metadata_fmt into bool
> > > > > - Rename unicam_fmt to unicam_format_info
> > > > > - Rename unicam_format_info variables to fmtinfo
> > > > > - Rename unicam_node.v_fmt to fmt
> > > > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > > > - Make metadata formats line-based
> > > > > - Validate format on metadata video device
> > > > > - Add Co-devlopped-by tags
> > > > >
> > > > > Changes since v3:
> > > > >
> > > > > - Add the vendor prefix for DT name
> > > > > - Use the reg-names in DT parsing
> > > > > - Remove MAINTAINERS entry
> > > > >
> > > > > Changes since v2:
> > > > >
> > > > > - Change code organization
> > > > > - Remove unused variables
> > > > > - Correct the fmt_meta functions
> > > > > - Rewrite the start/stop streaming
> > > > >   - You can now start the image node alone, but not the metadata one
> > > > >   - The buffers are allocated per-node
> > > > >   - only the required stream is started, if the route exists and is
> > > > >     enabled
> > > > > - Prefix the macros with UNICAM_ to not have too generic names
> > > > > - Drop colorspace support
> > > > >
> > > > > Changes since v1:
> > > > >
> > > > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > > > ---
> > > > >  MAINTAINERS                                   |    1 +
> > > > >  drivers/media/platform/Kconfig                |    1 +
> > > > >  drivers/media/platform/Makefile               |    1 +
> > > > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > > > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > > > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > > > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > > > >  7 files changed, 2891 insertions(+)
> > > > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > > > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > >
> > > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > > index e50a59654e6e..cc350729f467 100644
> > > > > --- a/MAINTAINERS
> > > > > +++ b/MAINTAINERS
> > > > > @@ -4002,6 +4002,7 @@ M:    Raspberry Pi Kernel Maintenance <[e-mail]>
> > > > >  L: [e-mail]
> > > > >  S: Maintained
> > > > >  F: Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > > > > +F: drivers/media/platform/bcm2835/
> > > > >
> > > > >  BROADCOM BCM47XX MIPS ARCHITECTURE
> > > > >  M: Hauke Mehrtens <[e-mail]>
> > > > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > > > index 91e54215de3a..2d79bfc68c15 100644
> > > > > --- a/drivers/media/platform/Kconfig
> > > > > +++ b/drivers/media/platform/Kconfig
> > > > > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> > > > >  source "drivers/media/platform/amphion/Kconfig"
> > > > >  source "drivers/media/platform/aspeed/Kconfig"
> > > > >  source "drivers/media/platform/atmel/Kconfig"
> > > > > +source "drivers/media/platform/broadcom/Kconfig"
> > > > >  source "drivers/media/platform/cadence/Kconfig"
> > > > >  source "drivers/media/platform/chips-media/Kconfig"
> > > > >  source "drivers/media/platform/intel/Kconfig"
> > > > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > > > > index 3296ec1ebe16..da17301f7439 100644
> > > > > --- a/drivers/media/platform/Makefile
> > > > > +++ b/drivers/media/platform/Makefile
> > > > > @@ -10,6 +10,7 @@ obj-y += amlogic/
> > > > >  obj-y += amphion/
> > > > >  obj-y += aspeed/
> > > > >  obj-y += atmel/
> > > > > +obj-y += broadcom/
> > > > >  obj-y += cadence/
> > > > >  obj-y += chips-media/
> > > > >  obj-y += intel/
> > > > > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > > > > new file mode 100644
> > > > > index 000000000000..cc2c9afcc948
> > > > > --- /dev/null
> > > > > +++ b/drivers/media/platform/broadcom/Kconfig
> > > > > @@ -0,0 +1,23 @@
> > > > > +# SPDX-License-Identifier: GPL-2.0
> > > > > +
> > > > > +config VIDEO_BCM2835_UNICAM
> > > > > +   tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > > > > +   depends on ARCH_BCM2835 || COMPILE_TEST
> > > > > +   depends on PM
> > > > > +   depends on VIDEO_DEV
> > > > > +   select MEDIA_CONTROLLER
> > > > > +   select V4L2_FWNODE
> > > > > +   select VIDEO_V4L2_SUBDEV_API
> > > > > +   select VIDEOBUF2_DMA_CONTIG
> > > > > +   help
> > > > > +     Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > > > > +     This is a V4L2 driver that controls the CSI-2 receiver directly,
> > > > > +     independently from the VC4 firmware.
> > > > > +
> > > > > +     This driver is mutually exclusive with the use of bcm2835-camera. The
> > > > > +     firmware will disable all access to the peripheral from within the
> > > > > +     firmware if it finds a DT node using it, and bcm2835-camera will
> > > > > +     therefore fail to probe.
> > > > > +
> > > > > +     To compile this driver as a module, choose M here. The module will be
> > > > > +     called bcm2835-unicam.
> > > > > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > > > > new file mode 100644
> > > > > index 000000000000..03d2045aba2e
> > > > > --- /dev/null
> > > > > +++ b/drivers/media/platform/broadcom/Makefile
> > > > > @@ -0,0 +1,3 @@
> > > > > +# SPDX-License-Identifier: GPL-2.0
> > > > > +
> > > > > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > > new file mode 100644
> > > > > index 000000000000..84775fd2fac5
> > > > > --- /dev/null
> > > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > > @@ -0,0 +1,255 @@
> > > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > > +
> > > > > +/*
> > > > > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> > > >
> > > > Anything up to 2024?
> > >
> > > Not really. The registers haven't really changed :-) I'll update the
> > > copyright in the .c file though.
> > >
> > > > > + * Dave Stevenson <[e-mail]>
> > > > > + */
> > >
> > > [snip]
> > >
> > > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > > new file mode 100644
> > > > > index 000000000000..716c89b8a217
> > > > > --- /dev/null
> > > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > > @@ -0,0 +1,2607 @@
> > >
> > > [snip]
> > >
> > > > > +static irqreturn_t unicam_isr(int irq, void *dev)
> > > > > +{
> > > > > +   struct unicam_device *unicam = dev;
> > > > > +   unsigned int lines_done = unicam_get_lines_done(dev);
> > > > > +   unsigned int sequence = unicam->sequence;
> > > > > +   unsigned int i;
> > > > > +   u32 ista, sta;
> > > > > +   bool fe;
> > > > > +   u64 ts;
> > > > > +
> > > > > +   sta = unicam_reg_read(unicam, UNICAM_STA);
> > > > > +   /* Write value back to clear the interrupts */
> > > > > +   unicam_reg_write(unicam, UNICAM_STA, sta);
> > > > > +
> > > > > +   ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > > > > +   /* Write value back to clear the interrupts */
> > > > > +   unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > > > > +
> > > > > +   dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > > > > +           ista, sta, sequence, lines_done);
> > > > > +
> > > > > +   if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > > > > +           return IRQ_HANDLED;
> > > > > +
> > > > > +   /*
> > > > > +    * Look for either the Frame End interrupt or the Packet Capture status
> > > > > +    * to signal a frame end.
> > > > > +    */
> > > > > +   fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > > > > +
> > > > > +   /*
> > > > > +    * We must run the frame end handler first. If we have a valid next_frm
> > > > > +    * and we get a simultaneout FE + FS interrupt, running the FS handler
> > > > > +    * first would null out the next_frm ptr and we would have lost the
> > > > > +    * buffer forever.
> > > > > +    */
> > > > > +   if (fe) {
> > > > > +           /*
> > > > > +            * Ensure we have swapped buffers already as we can't
> > > > > +            * stop the peripheral. If no buffer is available, use a
> > > > > +            * dummy buffer to dump out frames until we get a new buffer
> > > > > +            * to use.
> > > > > +            */
> > > > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > > +                   if (!unicam->node[i].streaming)
> > > > > +                           continue;
> > > > > +
> > > > > +                   /*
> > > > > +                    * If cur_frm == next_frm, it means we have not had
> > > > > +                    * a chance to swap buffers, likely due to having
> > > > > +                    * multiple interrupts occurring simultaneously (like FE
> > > > > +                    * + FS + LS). In this case, we cannot signal the buffer
> > > > > +                    * as complete, as the HW will reuse that buffer.
> > > > > +                    */
> > > > > +                   if (unicam->node[i].cur_frm &&
> > > > > +                       unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > > > > +                           unicam_process_buffer_complete(&unicam->node[i],
> > > > > +                                                          sequence);
> > > > > +                   unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > > > > +           }
> > > > > +           unicam->sequence++;
> > > >
> > > > Does access to this data need to be serialised somehow.
> > >
> > > Given that it's only accessed from the interrupt handler (beside
> > > start_streaming time, before starting the hardware), I don't think so.
> > >
> > > > > +   }
> > > > > +
> > > > > +   if (ista & UNICAM_FSI) {
> > > > > +           /*
> > > > > +            * Timestamp is to be when the first data byte was captured,
> > > > > +            * aka frame start.
> > > > > +            */
> > > > > +           ts = ktime_get_ns();
> > > > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > > +                   if (!unicam->node[i].streaming)
> > > > > +                           continue;
> > > > > +
> > > > > +                   if (unicam->node[i].cur_frm)
> > > > > +                           unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > > > > +                                                           ts;
> > > > > +                   else
> > > > > +                           dev_dbg(unicam->v4l2_dev.dev,
> > > > > +                                   "ISR: [%d] Dropping frame, buffer not available at FS\n",
> > > > > +                                   i);
> > > > > +                   /*
> > > > > +                    * Set the next frame output to go to a dummy frame
> > > > > +                    * if we have not managed to obtain another frame
> > > > > +                    * from the queue.
> > > > > +                    */
> > > > > +                   unicam_schedule_dummy_buffer(&unicam->node[i]);
> > > > > +           }
> > > > > +
> > > > > +           unicam_queue_event_sof(unicam);
> > > > > +   }
> > > > > +
> > > > > +   /*
> > > > > +    * Cannot swap buffer at frame end, there may be a race condition
> > > > > +    * where the HW does not actually swap it if the new frame has
> > > > > +    * already started.
> > > > > +    */
> > > > > +   if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > > > > +           for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > > +                   if (!unicam->node[i].streaming)
> > > > > +                           continue;
> > > > > +
> > > > > +                   spin_lock(&unicam->node[i].dma_queue_lock);
> > > > > +                   if (!list_empty(&unicam->node[i].dma_queue) &&
> > > > > +                       !unicam->node[i].next_frm)
> > > > > +                           unicam_schedule_next_buffer(&unicam->node[i]);
> > > > > +                   spin_unlock(&unicam->node[i].dma_queue_lock);
> > > > > +           }
> > > > > +   }
> > > > > +
> > > > > +   if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > > > > +           /* Switch out of trigger mode if selected */
> > > > > +           unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > > > +           unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > > > > +   }
> > > > > +   return IRQ_HANDLED;
> > > > > +}
> > > > > +
> > > > > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > > > > +{
> > > > > +   struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > > > +   u32 pack, unpack;
> > > > > +   u32 val;
> > > > > +
> > > > > +   if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > > > > +           unpack = UNICAM_PUM_NONE;
> > > > > +           pack = UNICAM_PPM_NONE;
> > > > > +   } else {
> > > > > +           switch (node->fmtinfo->depth) {
> > > > > +           case 8:
> > > > > +                   unpack = UNICAM_PUM_UNPACK8;
> > > > > +                   break;
> > > > > +           case 10:
> > > > > +                   unpack = UNICAM_PUM_UNPACK10;
> > > > > +                   break;
> > > > > +           case 12:
> > > > > +                   unpack = UNICAM_PUM_UNPACK12;
> > > > > +                   break;
> > > > > +           case 14:
> > > > > +                   unpack = UNICAM_PUM_UNPACK14;
> > > > > +                   break;
> > > > > +           case 16:
> > > > > +                   unpack = UNICAM_PUM_UNPACK16;
> > > > > +                   break;
> > > > > +           default:
> > > > > +                   unpack = UNICAM_PUM_NONE;
> > > > > +                   break;
> > > > > +           }
> > > > > +
> > > > > +           /* Repacking is always to 16bpp */
> > > > > +           pack = UNICAM_PPM_PACK16;
> > > >
> > > > Also 8-bit data?
> > >
> > > Not that I know of. The 8-bit entries in unicam_image_formats have no
> > > .unpacked_fourcc field, so the condition in the if above will always be
> > > true for those as they can only be selected by setting the pixel format
> > > to fmtinfo->fourcc.
> >
> > Correct.
> > The unpacking / packing doesn't bit shift, hence 10P can be unpacked
> > to 10, 12P to 12, and 14P to 14, but there is no 8bit unpacked into
> > the LSBs of 16 bit words defined as a V4L2 format.
> >
> > You can configure packing to produce 10P, 12P, etc, but without the
> > bitshift it has no real use.
> >
> > MSBs get dropped if you try packing to a smaller bit depth than the
> > source, so packing to 8 bit from any other depth results in unusable
> > output.
> >
> > If being really critical, then there is no point in having the case 8
> > and case 16 in this switch as they will never be selected.
>
> As we have space to spare in the unicam_format_info structure due to
> padding, I'll move the unpack value there and drop the switch.

As it ends up being a 1:1 mapping, that would work.

Originally I believed unicam did the bit-shifting which made offering
the flexibility useful, but that proved to be wrong.

  Dave

> > > > > +   }
> >
> > <snip>
>
> --
> Regards,
>
> Laurent Pinchart

Sakari Ailus March 26, 2024, 10:23 p.m. UTC | #16

Hi Laurent,

On Tue, Mar 26, 2024 at 03:50:28AM +0200, Laurent Pinchart wrote:
> On Tue, Mar 26, 2024 at 03:37:09AM +0200, Laurent Pinchart wrote:
> > Hi Sakari,
> > 
> > On Mon, Mar 25, 2024 at 06:36:49PM +0000, Sakari Ailus wrote:
> > > On Fri, Mar 01, 2024 at 11:32:24PM +0200, Laurent Pinchart wrote:
> > > > From: Dave Stevenson <[e-mail]>
> > > > 
> > > > Add a driver for the Unicam camera receiver block on BCM283x processors.
> > > > It is represented as two video device nodes: unicam-image and
> > > > unicam-embedded which are connected to an internal subdev (named
> > > > unicam-subdev) in order to manage streams routing.
> > > > 
> > > > Signed-off-by: Dave Stevenson <[e-mail]>
> > > > Co-developed-by: Naushir Patuck <[e-mail]>
> > > > Signed-off-by: Naushir Patuck <[e-mail]>
> > > > Co-developed-by: Jean-Michel Hautbois <[e-mail]>
> > > > Signed-off-by: Jean-Michel Hautbois <[e-mail]>
> > > > Co-developed-by: Laurent Pinchart <[e-mail]>
> > > > Signed-off-by: Laurent Pinchart <[e-mail]>
> > > 
> > > Thanks for submitting this, it's the cleanest and neatest Unicom driver
> > 
> > Unicam, or if you insist Unicorn, but not Unicom :-)

A Unicorn driver? Hmm. Maybe Unicam is indeed the best choice here?

> > 
> > > I've ever seen!
> > > 
> > > Some mostly unimportant comments below, however the bus-type issue needs to
> > > be addressed.
> > > 
> > > > ---
> > > > Changes since v5:
> > > > 
> > > > - Move to drivers/media/platform/broadcom/
> > > > - Port to the upstream V4L2 streams API
> > > > - Rebase on latest metadata API proposal
> > > > - Add missing error message
> > > > - Drop unneeded documentation block for unicam_isr()
> > > > - Drop unneeded dev_dbg() and dev_err() messages
> > > > - Drop unneeded streams_mask and fmt checks
> > > > - Drop unused unicam_sd_pad_is_sink()
> > > > - Drop unneeded includes
> > > > - Drop v4l2_ctrl_subscribe_event() call
> > > > - Use pm_runtime_resume_and_get()
> > > > - Indentation and line wrap fixes
> > > > - Let the framework set bus_info
> > > > - Use v4l2_fwnode_endpoint_parse()
> > > > - Fix media device cleanup
> > > > - Drop lane reordering checks
> > > > - Fix subdev state locking
> > > > - Drop extra debug messages
> > > > - Move clock handling to runtime PM handlers
> > > > - Reorder functions
> > > > - Rename init functions for more clarity
> > > > - Initialize runtime PM earlier
> > > > - Clarify error messages
> > > > - Simplify subdev init with local variable
> > > > - Fix subdev cleanup
> > > > - Fix typos and indentation
> > > > - Don't initialize local variables needlessly
> > > > - Simplify num lanes check
> > > > - Fix metadata handling in subdev set_fmt
> > > > - Drop manual fallback to .s_stream()
> > > > - Pass v4l2_pix_format to unicam_calc_format_size_bpl()
> > > > - Simplify unicam_set_default_format()
> > > > - Fix default format settings
> > > > - Add busy check in unicam_s_fmt_meta()
> > > > - Add missing \n at end of format strings
> > > > - Fix metadata handling in subdev set_fmt
> > > > - Fix locking when starting streaming
> > > > - Return buffers from start streaming fails
> > > > - Fix format validation for metadata node
> > > > - Use video_device_pipeline_{start,stop}() helpers
> > > > - Simplify format enumeration
> > > > - Drop unset variable
> > > > - Update MAINTAINERS entry
> > > > - Update to the upstream v4l2_async_nf API
> > > > - Update to the latest subdev routing API
> > > > - Update to the latest subdev state API
> > > > - Move from subdev .init_cfg() to .init_state()
> > > > - Update to the latest videobuf2 API
> > > > - Fix v4l2_subdev_enable_streams() error check
> > > > - Use correct pad for the connected subdev
> > > > - Return buffers to vb2 when start streaming fails
> > > > - Improve debugging in start streaming handler
> > > > - Simplify DMA address management
> > > > - Drop comment about bcm2835-camera driver
> > > > - Clarify comments that explain min/max sizes
> > > > - Pass v4l2_pix_format to unicam_try_fmt()
> > > > - Drop unneeded local variables
> > > > - Rename image-related constants and functions
> > > > - Turn unicam_fmt.metadata_fmt into bool
> > > > - Rename unicam_fmt to unicam_format_info
> > > > - Rename unicam_format_info variables to fmtinfo
> > > > - Rename unicam_node.v_fmt to fmt
> > > > - Add metadata formats for RAW10, RAW12 and RAW14
> > > > - Make metadata formats line-based
> > > > - Validate format on metadata video device
> > > > - Add Co-devlopped-by tags
> > > > 
> > > > Changes since v3:
> > > > 
> > > > - Add the vendor prefix for DT name
> > > > - Use the reg-names in DT parsing
> > > > - Remove MAINTAINERS entry
> > > > 
> > > > Changes since v2:
> > > > 
> > > > - Change code organization
> > > > - Remove unused variables
> > > > - Correct the fmt_meta functions
> > > > - Rewrite the start/stop streaming
> > > >   - You can now start the image node alone, but not the metadata one
> > > >   - The buffers are allocated per-node
> > > >   - only the required stream is started, if the route exists and is
> > > >     enabled
> > > > - Prefix the macros with UNICAM_ to not have too generic names
> > > > - Drop colorspace support
> > > > 
> > > > Changes since v1:
> > > > 
> > > > - Replace the unicam_{info,debug,error} macros with dev_*()
> > > > ---
> > > >  MAINTAINERS                                   |    1 +
> > > >  drivers/media/platform/Kconfig                |    1 +
> > > >  drivers/media/platform/Makefile               |    1 +
> > > >  drivers/media/platform/broadcom/Kconfig       |   23 +
> > > >  drivers/media/platform/broadcom/Makefile      |    3 +
> > > >  .../platform/broadcom/bcm2835-unicam-regs.h   |  255 ++
> > > >  .../media/platform/broadcom/bcm2835-unicam.c  | 2607 +++++++++++++++++
> > > >  7 files changed, 2891 insertions(+)
> > > >  create mode 100644 drivers/media/platform/broadcom/Kconfig
> > > >  create mode 100644 drivers/media/platform/broadcom/Makefile
> > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > >  create mode 100644 drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > 
> > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > index e50a59654e6e..cc350729f467 100644
> > > > --- a/MAINTAINERS
> > > > +++ b/MAINTAINERS
> > > > @@ -4002,6 +4002,7 @@ M:	Raspberry Pi Kernel Maintenance <[e-mail]>
> > > >  L:	[e-mail]
> > > >  S:	Maintained
> > > >  F:	Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
> > > > +F:	drivers/media/platform/bcm2835/
> > > >  
> > > >  BROADCOM BCM47XX MIPS ARCHITECTURE
> > > >  M:	Hauke Mehrtens <[e-mail]>
> > > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> > > > index 91e54215de3a..2d79bfc68c15 100644
> > > > --- a/drivers/media/platform/Kconfig
> > > > +++ b/drivers/media/platform/Kconfig
> > > > @@ -67,6 +67,7 @@ source "drivers/media/platform/amlogic/Kconfig"
> > > >  source "drivers/media/platform/amphion/Kconfig"
> > > >  source "drivers/media/platform/aspeed/Kconfig"
> > > >  source "drivers/media/platform/atmel/Kconfig"
> > > > +source "drivers/media/platform/broadcom/Kconfig"
> > > >  source "drivers/media/platform/cadence/Kconfig"
> > > >  source "drivers/media/platform/chips-media/Kconfig"
> > > >  source "drivers/media/platform/intel/Kconfig"
> > > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> > > > index 3296ec1ebe16..da17301f7439 100644
> > > > --- a/drivers/media/platform/Makefile
> > > > +++ b/drivers/media/platform/Makefile
> > > > @@ -10,6 +10,7 @@ obj-y += amlogic/
> > > >  obj-y += amphion/
> > > >  obj-y += aspeed/
> > > >  obj-y += atmel/
> > > > +obj-y += broadcom/
> > > >  obj-y += cadence/
> > > >  obj-y += chips-media/
> > > >  obj-y += intel/
> > > > diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
> > > > new file mode 100644
> > > > index 000000000000..cc2c9afcc948
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/Kconfig
> > > > @@ -0,0 +1,23 @@
> > > > +# SPDX-License-Identifier: GPL-2.0
> > > > +
> > > > +config VIDEO_BCM2835_UNICAM
> > > > +	tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
> > > > +	depends on ARCH_BCM2835 || COMPILE_TEST
> > > > +	depends on PM
> > > > +	depends on VIDEO_DEV
> > > > +	select MEDIA_CONTROLLER
> > > > +	select V4L2_FWNODE
> > > > +	select VIDEO_V4L2_SUBDEV_API
> > > > +	select VIDEOBUF2_DMA_CONTIG
> > > > +	help
> > > > +	  Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
> > > > +	  This is a V4L2 driver that controls the CSI-2 receiver directly,
> > > > +	  independently from the VC4 firmware.
> > > > +
> > > > +	  This driver is mutually exclusive with the use of bcm2835-camera. The
> > > > +	  firmware will disable all access to the peripheral from within the
> > > > +	  firmware if it finds a DT node using it, and bcm2835-camera will
> > > > +	  therefore fail to probe.
> > > > +
> > > > +	  To compile this driver as a module, choose M here. The module will be
> > > > +	  called bcm2835-unicam.
> > > > diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
> > > > new file mode 100644
> > > > index 000000000000..03d2045aba2e
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/Makefile
> > > > @@ -0,0 +1,3 @@
> > > > +# SPDX-License-Identifier: GPL-2.0
> > > > +
> > > > +obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
> > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > new file mode 100644
> > > > index 000000000000..84775fd2fac5
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
> > > > @@ -0,0 +1,255 @@
> > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > +
> > > > +/*
> > > > + * Copyright (C) 2017-2020 Raspberry Pi Trading.
> > > 
> > > Anything up to 2024?
> > 
> > Not really. The registers haven't really changed :-) I'll update the
> > copyright in the .c file though.
> > 
> > > > + * Dave Stevenson <[e-mail]>
> > > > + */
> > 
> > [snip]
> > 
> > > > diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > new file mode 100644
> > > > index 000000000000..716c89b8a217
> > > > --- /dev/null
> > > > +++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
> > > > @@ -0,0 +1,2607 @@
> > 
> > [snip]
> > 
> > > > +static irqreturn_t unicam_isr(int irq, void *dev)
> > > > +{
> > > > +	struct unicam_device *unicam = dev;
> > > > +	unsigned int lines_done = unicam_get_lines_done(dev);
> > > > +	unsigned int sequence = unicam->sequence;
> > > > +	unsigned int i;
> > > > +	u32 ista, sta;
> > > > +	bool fe;
> > > > +	u64 ts;
> > > > +
> > > > +	sta = unicam_reg_read(unicam, UNICAM_STA);
> > > > +	/* Write value back to clear the interrupts */
> > > > +	unicam_reg_write(unicam, UNICAM_STA, sta);
> > > > +
> > > > +	ista = unicam_reg_read(unicam, UNICAM_ISTA);
> > > > +	/* Write value back to clear the interrupts */
> > > > +	unicam_reg_write(unicam, UNICAM_ISTA, ista);
> > > > +
> > > > +	dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
> > > > +		ista, sta, sequence, lines_done);
> > > > +
> > > > +	if (!(sta & (UNICAM_IS | UNICAM_PI0)))
> > > > +		return IRQ_HANDLED;
> > > > +
> > > > +	/*
> > > > +	 * Look for either the Frame End interrupt or the Packet Capture status
> > > > +	 * to signal a frame end.
> > > > +	 */
> > > > +	fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
> > > > +
> > > > +	/*
> > > > +	 * We must run the frame end handler first. If we have a valid next_frm
> > > > +	 * and we get a simultaneout FE + FS interrupt, running the FS handler
> > > > +	 * first would null out the next_frm ptr and we would have lost the
> > > > +	 * buffer forever.
> > > > +	 */
> > > > +	if (fe) {
> > > > +		/*
> > > > +		 * Ensure we have swapped buffers already as we can't
> > > > +		 * stop the peripheral. If no buffer is available, use a
> > > > +		 * dummy buffer to dump out frames until we get a new buffer
> > > > +		 * to use.
> > > > +		 */
> > > > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > +			if (!unicam->node[i].streaming)
> > > > +				continue;
> > > > +
> > > > +			/*
> > > > +			 * If cur_frm == next_frm, it means we have not had
> > > > +			 * a chance to swap buffers, likely due to having
> > > > +			 * multiple interrupts occurring simultaneously (like FE
> > > > +			 * + FS + LS). In this case, we cannot signal the buffer
> > > > +			 * as complete, as the HW will reuse that buffer.
> > > > +			 */
> > > > +			if (unicam->node[i].cur_frm &&
> > > > +			    unicam->node[i].cur_frm != unicam->node[i].next_frm)
> > > > +				unicam_process_buffer_complete(&unicam->node[i],
> > > > +							       sequence);
> > > > +			unicam->node[i].cur_frm = unicam->node[i].next_frm;
> > > > +		}
> > > > +		unicam->sequence++;
> > > 
> > > Does access to this data need to be serialised somehow.
> > 
> > Given that it's only accessed from the interrupt handler (beside
> > start_streaming time, before starting the hardware), I don't think so.

Ack. I guess a memory barrier would be theoretically needed although in
practice other locks will be taken so you might not have issues.

> > 
> > > > +	}
> > > > +
> > > > +	if (ista & UNICAM_FSI) {
> > > > +		/*
> > > > +		 * Timestamp is to be when the first data byte was captured,
> > > > +		 * aka frame start.
> > > > +		 */
> > > > +		ts = ktime_get_ns();
> > > > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > +			if (!unicam->node[i].streaming)
> > > > +				continue;
> > > > +
> > > > +			if (unicam->node[i].cur_frm)
> > > > +				unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
> > > > +								ts;
> > > > +			else
> > > > +				dev_dbg(unicam->v4l2_dev.dev,
> > > > +					"ISR: [%d] Dropping frame, buffer not available at FS\n",
> > > > +					i);
> > > > +			/*
> > > > +			 * Set the next frame output to go to a dummy frame
> > > > +			 * if we have not managed to obtain another frame
> > > > +			 * from the queue.
> > > > +			 */
> > > > +			unicam_schedule_dummy_buffer(&unicam->node[i]);
> > > > +		}
> > > > +
> > > > +		unicam_queue_event_sof(unicam);
> > > > +	}
> > > > +
> > > > +	/*
> > > > +	 * Cannot swap buffer at frame end, there may be a race condition
> > > > +	 * where the HW does not actually swap it if the new frame has
> > > > +	 * already started.
> > > > +	 */
> > > > +	if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
> > > > +		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
> > > > +			if (!unicam->node[i].streaming)
> > > > +				continue;
> > > > +
> > > > +			spin_lock(&unicam->node[i].dma_queue_lock);
> > > > +			if (!list_empty(&unicam->node[i].dma_queue) &&
> > > > +			    !unicam->node[i].next_frm)
> > > > +				unicam_schedule_next_buffer(&unicam->node[i]);
> > > > +			spin_unlock(&unicam->node[i].dma_queue_lock);
> > > > +		}
> > > > +	}
> > > > +
> > > > +	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
> > > > +		/* Switch out of trigger mode if selected */
> > > > +		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > > +		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
> > > > +	}
> > > > +	return IRQ_HANDLED;
> > > > +}
> > > > +
> > > > +static void unicam_set_packing_config(struct unicam_device *unicam)
> > > > +{
> > > > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > > +	u32 pack, unpack;
> > > > +	u32 val;
> > > > +
> > > > +	if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
> > > > +		unpack = UNICAM_PUM_NONE;
> > > > +		pack = UNICAM_PPM_NONE;
> > > > +	} else {
> > > > +		switch (node->fmtinfo->depth) {
> > > > +		case 8:
> > > > +			unpack = UNICAM_PUM_UNPACK8;
> > > > +			break;
> > > > +		case 10:
> > > > +			unpack = UNICAM_PUM_UNPACK10;
> > > > +			break;
> > > > +		case 12:
> > > > +			unpack = UNICAM_PUM_UNPACK12;
> > > > +			break;
> > > > +		case 14:
> > > > +			unpack = UNICAM_PUM_UNPACK14;
> > > > +			break;
> > > > +		case 16:
> > > > +			unpack = UNICAM_PUM_UNPACK16;
> > > > +			break;
> > > > +		default:
> > > > +			unpack = UNICAM_PUM_NONE;
> > > > +			break;
> > > > +		}
> > > > +
> > > > +		/* Repacking is always to 16bpp */
> > > > +		pack = UNICAM_PPM_PACK16;
> > > 
> > > Also 8-bit data?
> > 
> > Not that I know of. The 8-bit entries in unicam_image_formats have no
> > .unpacked_fourcc field, so the condition in the if above will always be
> > true for those as they can only be selected by setting the pixel format
> > to fmtinfo->fourcc.

Ok.

> > 
> > > > +	}
> > > > +
> > > > +	val = 0;
> > > 
> > > You could do initialisation in declaration.
> > 
> > Yes, but I think it's more readable to keep all the code that affects
> > the 'val' variable together.

If wal was a bit more descriptive name this would be a non-issue. Up to
you.

> > 
> > > > +	unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
> > > > +	unicam_set_field(&val, pack, UNICAM_PPM_MASK);
> > > > +	unicam_reg_write(unicam, UNICAM_IPIPE, val);
> > > > +}
> > > > +
> > > > +static void unicam_cfg_image_id(struct unicam_device *unicam)
> > > > +{
> > > > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > > +
> > > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > > +		/* CSI2 mode, hardcode VC 0 for now. */
> > > > +		unicam_reg_write(unicam, UNICAM_IDI0,
> > > > +				 (0 << 6) | node->fmtinfo->csi_dt);
> > > > +	} else {
> > > > +		/* CCP2 mode */
> > > > +		unicam_reg_write(unicam, UNICAM_IDI0,
> > > > +				 0x80 | node->fmtinfo->csi_dt);
> > > > +	}
> > > > +}
> > > > +
> > > > +static void unicam_enable_ed(struct unicam_device *unicam)
> > > > +{
> > > > +	u32 val = unicam_reg_read(unicam, UNICAM_DCS);
> > > > +
> > > > +	unicam_set_field(&val, 2, UNICAM_EDL_MASK);
> > > > +	/* Do not wrap at the end of the embedded data buffer */
> > > > +	unicam_set_field(&val, 0, UNICAM_DBOB);
> > > > +
> > > > +	unicam_reg_write(unicam, UNICAM_DCS, val);
> > > > +}
> > > > +
> > > > +static void unicam_start_rx(struct unicam_device *unicam,
> > > > +			    struct unicam_buffer *buf)
> > > > +{
> > > > +	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
> > > > +	int line_int_freq = node->fmt.fmt.pix.height >> 2;
> > > > +	unsigned int i;
> > > > +	u32 val;
> > > > +
> > > > +	if (line_int_freq < 128)
> > > > +		line_int_freq = 128;
> > > 
> > > 	line_int_freq = max(line_int_freq, 128);
> > Ack.
> > 
> > > > +
> > > > +	/* Enable lane clocks */
> > > > +	val = 1;
> > > 
> > > Initialise in the loop initialisation below, I'd say.
> > 
> > How about
> > 
> > 	val = 0x55 & GENMASK(unicam->pipe.num_data_lanes * 2 - 1, 0);
> 
> I meant
> 
>  	val = 0x155 & GENMASK(unicam->pipe.num_data_lanes * 2 + 1, 0);
> 
> Maybe a comment would be useful ?
> 
> 	/*
> 	 * Enable lane clocks. The register is structured as follows:
> 	 *
> 	 * [9:8] - DAT3
> 	 * [7:6] - DAT2
> 	 * [5:4] - DAT1
> 	 * [3:2] - DAT0
> 	 * [1:0] - CLK
> 	 *
> 	 * Enabled lane must be set to b01, and disabled lanes to b00. The clock
> 	 * lane is always enabled.
> 	 */
> 	val = 0x155 & GENMASK(unicam->pipe.num_data_lanes * 2 + 1, 0);

Seems good to me.

> 
> > > > +	for (i = 0; i < unicam->active_data_lanes; i++)
> > > > +		val = val << 2 | 1;
> > > > +	unicam_clk_write(unicam, val);
> > > > +
> > > > +	/* Basic init */
> > > > +	unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
> > > > +
> > > > +	/* Enable analogue control, and leave in reset. */
> > > > +	val = UNICAM_AR;
> > > > +	unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
> > > > +	unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
> > > > +	unicam_reg_write(unicam, UNICAM_ANA, val);
> > > > +	usleep_range(1000, 2000);
> > > > +
> > > > +	/* Come out of reset */
> > > > +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
> > > > +
> > > > +	/* Peripheral reset */
> > > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
> > > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
> > > > +
> > > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
> > > > +
> > > > +	/* Enable Rx control. */
> > > > +	val = unicam_reg_read(unicam, UNICAM_CTRL);
> > > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > > +		unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
> > > > +		unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
> > > > +	} else {
> > > > +		unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
> > > > +		unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
> > > > +	}
> > > > +	/* Packet framer timeout */
> > > > +	unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
> > > > +	unicam_set_field(&val, 128, UNICAM_OET_MASK);
> > > > +	unicam_reg_write(unicam, UNICAM_CTRL, val);
> > > > +
> > > > +	unicam_reg_write(unicam, UNICAM_IHWIN, 0);
> > > > +	unicam_reg_write(unicam, UNICAM_IVWIN, 0);
> > > > +
> > > > +	/* AXI bus access QoS setup */
> > > > +	val = unicam_reg_read(unicam, UNICAM_PRI);
> > > > +	unicam_set_field(&val, 0, UNICAM_BL_MASK);
> > > > +	unicam_set_field(&val, 0, UNICAM_BS_MASK);
> > > > +	unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
> > > > +	unicam_set_field(&val, 8, UNICAM_NP_MASK);
> > > > +	unicam_set_field(&val, 2, UNICAM_PT_MASK);
> > > > +	unicam_set_field(&val, 1, UNICAM_PE);
> > > > +	unicam_reg_write(unicam, UNICAM_PRI, val);
> > > > +
> > > > +	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
> > > > +
> > > > +	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
> > > > +	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
> > > > +	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
> > > > +	unicam_reg_write(unicam, UNICAM_ICTL, val);
> > > > +	unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
> > > > +	unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
> > > > +
> > > > +	/* tclk_term_en */
> > > > +	unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
> > > > +	/* tclk_settle */
> > > > +	unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
> > > > +	/* td_term_en */
> > > > +	unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
> > > > +	/* ths_settle */
> > > > +	unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
> > > > +	/* trx_enable */
> > > > +	unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
> > > > +
> > > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
> > > > +
> > > > +	/* Packet compare setup - required to avoid missing frame ends */
> > > > +	val = 0;
> > > > +	unicam_set_field(&val, 1, UNICAM_PCE);
> > > > +	unicam_set_field(&val, 1, UNICAM_GI);
> > > > +	unicam_set_field(&val, 1, UNICAM_CPH);
> > > > +	unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
> > > > +	unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
> > > > +	unicam_reg_write(unicam, UNICAM_CMP0, val);
> > > > +
> > > > +	/* Enable clock lane and set up terminations */
> > > > +	val = 0;
> > > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > > +		/* CSI2 */
> > > > +		unicam_set_field(&val, 1, UNICAM_CLE);
> > > > +		unicam_set_field(&val, 1, UNICAM_CLLPE);
> > > > +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > > > +			unicam_set_field(&val, 1, UNICAM_CLTRE);
> > > > +			unicam_set_field(&val, 1, UNICAM_CLHSE);
> > > > +		}
> > > > +	} else {
> > > > +		/* CCP2 */
> > > > +		unicam_set_field(&val, 1, UNICAM_CLE);
> > > > +		unicam_set_field(&val, 1, UNICAM_CLHSE);
> > > > +		unicam_set_field(&val, 1, UNICAM_CLTRE);
> > > > +	}
> > > > +	unicam_reg_write(unicam, UNICAM_CLK, val);
> > > > +
> > > > +	/*
> > > > +	 * Enable required data lanes with appropriate terminations.
> > > > +	 * The same value needs to be written to UNICAM_DATn registers for
> > > > +	 * the active lanes, and 0 for inactive ones.
> > > > +	 */
> > > > +	val = 0;
> > > > +	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
> > > > +		/* CSI2 */
> > > > +		unicam_set_field(&val, 1, UNICAM_DLE);
> > > > +		unicam_set_field(&val, 1, UNICAM_DLLPE);
> > > > +		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
> > > > +			unicam_set_field(&val, 1, UNICAM_DLTRE);
> > > > +			unicam_set_field(&val, 1, UNICAM_DLHSE);
> > > > +		}
> > > > +	} else {
> > > > +		/* CCP2 */
> > > > +		unicam_set_field(&val, 1, UNICAM_DLE);
> > > > +		unicam_set_field(&val, 1, UNICAM_DLHSE);
> > > > +		unicam_set_field(&val, 1, UNICAM_DLTRE);
> > > > +	}
> > > > +	unicam_reg_write(unicam, UNICAM_DAT0, val);
> > > > +
> > > > +	if (unicam->active_data_lanes == 1)
> > > > +		val = 0;
> > > > +	unicam_reg_write(unicam, UNICAM_DAT1, val);
> > > > +
> > > > +	if (unicam->max_data_lanes > 2) {
> > > > +		/*
> > > > +		 * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
> > > > +		 * instance supports more than 2 data lanes.
> > > > +		 */
> > > > +		if (unicam->active_data_lanes == 2)
> > > > +			val = 0;
> > > > +		unicam_reg_write(unicam, UNICAM_DAT2, val);
> > > > +
> > > > +		if (unicam->active_data_lanes == 3)
> > > > +			val = 0;
> > > > +		unicam_reg_write(unicam, UNICAM_DAT3, val);
> > > > +	}
> > > > +
> > > > +	unicam_reg_write(unicam, UNICAM_IBLS,
> > > > +			 node->fmt.fmt.pix.bytesperline);
> > > > +	unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
> > > > +	unicam_set_packing_config(unicam);
> > > > +	unicam_cfg_image_id(unicam);
> > > > +
> > > > +	val = unicam_reg_read(unicam, UNICAM_MISC);
> > > > +	unicam_set_field(&val, 1, UNICAM_FL0);
> > > > +	unicam_set_field(&val, 1, UNICAM_FL1);
> > > > +	unicam_reg_write(unicam, UNICAM_MISC, val);
> > > > +
> > > > +	/* Enable peripheral */
> > > > +	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
> > > > +
> > > > +	/* Load image pointers */
> > > > +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
> > > > +
> > > > +	/*
> > > > +	 * Enable trigger only for the first frame to
> > > > +	 * sync correctly to the FS from the source.
> > > > +	 */
> > > > +	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
> > > > +}
> > 
> > [snip]
> > 
> > > > +static int unicam_async_nf_init(struct unicam_device *unicam)
> > > > +{
> > > > +	struct v4l2_fwnode_endpoint ep = { };
> > > 
> > > If the bus-type property is mandatory and you have no stated defaults
> > > anywhere, this is fine. I.e. all the relevant properties would need to be

Actually this is a non-issue nowadays: bus in struct v4l2_fwnode_endpoint
is no longer a union.

> > > mandatory.
> > 
> > They are, as far as I can tell (well, the clock-noncontinuous property
> > is not mandatory, but that's expected as it's a flag).
> > 
> > > > +	struct fwnode_handle *ep_handle;
> > > > +	struct v4l2_async_connection *asc;
> > > > +	int ret;
> > > > +
> > > > +	ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
> > > > +				   &unicam->max_data_lanes);
> > > > +	if (ret < 0) {
> > > > +		dev_err(unicam->dev, "Missing %s DT property\n",
> > > > +			"brcm,num-data-lanes");
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	/* Get and parse the local endpoint. */
> > > > +	ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
> > > > +						    FWNODE_GRAPH_ENDPOINT_NEXT);
> > > > +	if (!ep_handle) {
> > > > +		dev_err(unicam->dev, "No endpoint found\n");
> > > > +		return -ENODEV;
> > > > +	}
> > > > +
> > > > +	ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
> > > > +	if (ret) {
> > > > +		dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
> > > > +		goto error;
> > > > +	}
> > > > +
> > > > +	unicam->bus_type = ep.bus_type;
> > > > +
> > > > +	switch (ep.bus_type) {
> > > > +	case V4L2_MBUS_CSI2_DPHY: {
> > > > +		unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
> > > > +
> > > > +		if (num_data_lanes != 1 && num_data_lanes != 2 &&
> > > > +		    num_data_lanes != 4) {
> > > > +			dev_err(unicam->dev, "%u data lanes not supported\n",
> > > > +				num_data_lanes);
> > > > +			goto error;
> > > > +		}
> > > > +
> > > > +		if (num_data_lanes > unicam->max_data_lanes) {
> > > > +			dev_err(unicam->dev,
> > > > +				"Endpoint uses %u data lanes when %u are supported\n",
> > > > +				num_data_lanes, unicam->max_data_lanes);
> > > > +			goto error;
> > > > +		}
> > > > +
> > > > +		unicam->active_data_lanes = num_data_lanes;
> > > > +		unicam->bus_flags = ep.bus.mipi_csi2.flags;
> > > > +		break;
> > > > +	}
> > > > +
> > > > +	case V4L2_MBUS_CCP2:
> > > > +		unicam->max_data_lanes = 1;
> > > > +		unicam->active_data_lanes = 1;
> > > > +		unicam->bus_flags = ep.bus.mipi_csi1.strobe;
> > > > +		break;
> > > > +
> > > > +	default:
> > > > +		/* Unsupported bus type */
> > > > +		dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
> > > > +		goto error;
> > > > +	}
> > > > +
> > > > +	/* Initialize and register the async notifier. */
> > > > +	v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
> > > > +
> > > > +	asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
> > > > +					      struct v4l2_async_connection);
> > > > +	fwnode_handle_put(ep_handle);
> > > > +	ep_handle = NULL;
> > > > +
> > > > +	if (IS_ERR(asc)) {
> > > > +		ret = PTR_ERR(asc);
> > > > +		dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
> > > > +			ret);
> > > > +		goto error;
> > > > +	}
> > > > +
> > > > +	unicam->notifier.ops = &unicam_async_ops;
> > > > +
> > > > +	ret = v4l2_async_nf_register(&unicam->notifier);
> > > > +	if (ret) {
> > > > +		dev_err(unicam->dev, "Error registering device notifier: %d\n",
> > > > +			ret);
> > > > +		goto error;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +
> > > > +error:
> > > > +	fwnode_handle_put(ep_handle);
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +/* -----------------------------------------------------------------------------
> > > > + * Probe & remove
> > > > + */
> > > > +
> > > > +static int unicam_media_init(struct unicam_device *unicam)
> > > > +{
> > > > +	int ret;
> > > > +
> > > > +	unicam->mdev.dev = unicam->dev;
> > > > +	strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
> > > > +		sizeof(unicam->mdev.model));
> > > > +	strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));
> > > 
> > > Isn't the field already zeroed?
> > 
> > Indeed. I'll drop this.
> > 
> > > 
> > > > +	unicam->mdev.hw_revision = 0;
> > > > +
> > > > +	media_device_init(&unicam->mdev);
> > > > +
> > > > +	unicam->v4l2_dev.mdev = &unicam->mdev;
> > > > +
> > > > +	ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
> > > > +	if (ret < 0) {
> > > > +		dev_err(unicam->dev, "Unable to register v4l2 device\n");
> > > > +		goto err_media_cleanup;
> > > > +	}
> > > > +
> > > > +	ret = media_device_register(&unicam->mdev);
> > > > +	if (ret < 0) {
> > > > +		dev_err(unicam->dev,
> > > > +			"Unable to register media-controller device\n");
> > > > +		goto err_v4l2_unregister;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +
> > > > +err_v4l2_unregister:
> > > > +	v4l2_device_unregister(&unicam->v4l2_dev);
> > > > +err_media_cleanup:
> > > > +	media_device_cleanup(&unicam->mdev);
> > > > +	return ret;
> > > > +}
> > 
> > [snip]
>

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index e50a59654e6e..cc350729f467 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4002,6 +4002,7 @@  M:	Raspberry Pi Kernel Maintenance <[e-mail]>
 L:	[e-mail]
 S:	Maintained
 F:	Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml
+F:	drivers/media/platform/bcm2835/
 
 BROADCOM BCM47XX MIPS ARCHITECTURE
 M:	Hauke Mehrtens <[e-mail]>
diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index 91e54215de3a..2d79bfc68c15 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -67,6 +67,7 @@  source "drivers/media/platform/amlogic/Kconfig"
 source "drivers/media/platform/amphion/Kconfig"
 source "drivers/media/platform/aspeed/Kconfig"
 source "drivers/media/platform/atmel/Kconfig"
+source "drivers/media/platform/broadcom/Kconfig"
 source "drivers/media/platform/cadence/Kconfig"
 source "drivers/media/platform/chips-media/Kconfig"
 source "drivers/media/platform/intel/Kconfig"
diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
index 3296ec1ebe16..da17301f7439 100644
--- a/drivers/media/platform/Makefile
+++ b/drivers/media/platform/Makefile
@@ -10,6 +10,7 @@  obj-y += amlogic/
 obj-y += amphion/
 obj-y += aspeed/
 obj-y += atmel/
+obj-y += broadcom/
 obj-y += cadence/
 obj-y += chips-media/
 obj-y += intel/
diff --git a/drivers/media/platform/broadcom/Kconfig b/drivers/media/platform/broadcom/Kconfig
new file mode 100644
index 000000000000..cc2c9afcc948
--- /dev/null
+++ b/drivers/media/platform/broadcom/Kconfig
@@ -0,0 +1,23 @@ 
+# SPDX-License-Identifier: GPL-2.0
+
+config VIDEO_BCM2835_UNICAM
+	tristate "Broadcom BCM283x/BCM271x Unicam video capture driver"
+	depends on ARCH_BCM2835 || COMPILE_TEST
+	depends on PM
+	depends on VIDEO_DEV
+	select MEDIA_CONTROLLER
+	select V4L2_FWNODE
+	select VIDEO_V4L2_SUBDEV_API
+	select VIDEOBUF2_DMA_CONTIG
+	help
+	  Say Y here to enable support for the BCM283x/BCM271x CSI-2 receiver.
+	  This is a V4L2 driver that controls the CSI-2 receiver directly,
+	  independently from the VC4 firmware.
+
+	  This driver is mutually exclusive with the use of bcm2835-camera. The
+	  firmware will disable all access to the peripheral from within the
+	  firmware if it finds a DT node using it, and bcm2835-camera will
+	  therefore fail to probe.
+
+	  To compile this driver as a module, choose M here. The module will be
+	  called bcm2835-unicam.
diff --git a/drivers/media/platform/broadcom/Makefile b/drivers/media/platform/broadcom/Makefile
new file mode 100644
index 000000000000..03d2045aba2e
--- /dev/null
+++ b/drivers/media/platform/broadcom/Makefile
@@ -0,0 +1,3 @@ 
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_VIDEO_BCM2835_UNICAM) += bcm2835-unicam.o
diff --git a/drivers/media/platform/broadcom/bcm2835-unicam-regs.h b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
new file mode 100644
index 000000000000..84775fd2fac5
--- /dev/null
+++ b/drivers/media/platform/broadcom/bcm2835-unicam-regs.h
@@ -0,0 +1,255 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/*
+ * Copyright (C) 2017-2020 Raspberry Pi Trading.
+ * Dave Stevenson <[e-mail]>
+ */
+
+#ifndef VC4_REGS_UNICAM_H
+#define VC4_REGS_UNICAM_H
+
+#include <linux/bits.h>
+
+/*
+ * The following values are taken from files found within the code drop
+ * made by Broadcom for the BCM21553 Graphics Driver, predominantly in
+ * brcm_usrlib/dag/vmcsx/vcinclude/hardware_vc4.h.
+ * They have been modified to be only the register offset.
+ */
+#define UNICAM_CTRL		0x000
+#define UNICAM_STA		0x004
+#define UNICAM_ANA		0x008
+#define UNICAM_PRI		0x00c
+#define UNICAM_CLK		0x010
+#define UNICAM_CLT		0x014
+#define UNICAM_DAT0		0x018
+#define UNICAM_DAT1		0x01c
+#define UNICAM_DAT2		0x020
+#define UNICAM_DAT3		0x024
+#define UNICAM_DLT		0x028
+#define UNICAM_CMP0		0x02c
+#define UNICAM_CMP1		0x030
+#define UNICAM_CAP0		0x034
+#define UNICAM_CAP1		0x038
+#define UNICAM_ICTL		0x100
+#define UNICAM_ISTA		0x104
+#define UNICAM_IDI0		0x108
+#define UNICAM_IPIPE		0x10c
+#define UNICAM_IBSA0		0x110
+#define UNICAM_IBEA0		0x114
+#define UNICAM_IBLS		0x118
+#define UNICAM_IBWP		0x11c
+#define UNICAM_IHWIN		0x120
+#define UNICAM_IHSTA		0x124
+#define UNICAM_IVWIN		0x128
+#define UNICAM_IVSTA		0x12c
+#define UNICAM_ICC		0x130
+#define UNICAM_ICS		0x134
+#define UNICAM_IDC		0x138
+#define UNICAM_IDPO		0x13c
+#define UNICAM_IDCA		0x140
+#define UNICAM_IDCD		0x144
+#define UNICAM_IDS		0x148
+#define UNICAM_DCS		0x200
+#define UNICAM_DBSA0		0x204
+#define UNICAM_DBEA0		0x208
+#define UNICAM_DBWP		0x20c
+#define UNICAM_DBCTL		0x300
+#define UNICAM_IBSA1		0x304
+#define UNICAM_IBEA1		0x308
+#define UNICAM_IDI1		0x30c
+#define UNICAM_DBSA1		0x310
+#define UNICAM_DBEA1		0x314
+#define UNICAM_MISC		0x400
+
+/*
+ * The following bitmasks are from the kernel released by Broadcom
+ * for Android - https://android.googlesource.com/kernel/bcm/
+ * The Rhea, Hawaii, and Java chips all contain the same VideoCore4
+ * Unicam block as BCM2835, as defined in eg
+ * arch/arm/mach-rhea/include/mach/rdb_A0/brcm_rdb_cam.h and similar.
+ * Values reworked to use the kernel BIT and GENMASK macros.
+ *
+ * Some of the bit mnenomics have been amended to match the datasheet.
+ */
+/* UNICAM_CTRL Register */
+#define UNICAM_CPE		BIT(0)
+#define UNICAM_MEM		BIT(1)
+#define UNICAM_CPR		BIT(2)
+#define UNICAM_CPM_MASK		GENMASK(3, 3)
+#define UNICAM_CPM_CSI2		0
+#define UNICAM_CPM_CCP2		1
+#define UNICAM_SOE		BIT(4)
+#define UNICAM_DCM_MASK		GENMASK(5, 5)
+#define UNICAM_DCM_STROBE	0
+#define UNICAM_DCM_DATA		1
+#define UNICAM_SLS		BIT(6)
+#define UNICAM_PFT_MASK		GENMASK(11, 8)
+#define UNICAM_OET_MASK		GENMASK(20, 12)
+
+/* UNICAM_STA Register */
+#define UNICAM_SYN		BIT(0)
+#define UNICAM_CS		BIT(1)
+#define UNICAM_SBE		BIT(2)
+#define UNICAM_PBE		BIT(3)
+#define UNICAM_HOE		BIT(4)
+#define UNICAM_PLE		BIT(5)
+#define UNICAM_SSC		BIT(6)
+#define UNICAM_CRCE		BIT(7)
+#define UNICAM_OES		BIT(8)
+#define UNICAM_IFO		BIT(9)
+#define UNICAM_OFO		BIT(10)
+#define UNICAM_BFO		BIT(11)
+#define UNICAM_DL		BIT(12)
+#define UNICAM_PS		BIT(13)
+#define UNICAM_IS		BIT(14)
+#define UNICAM_PI0		BIT(15)
+#define UNICAM_PI1		BIT(16)
+#define UNICAM_FSI_S		BIT(17)
+#define UNICAM_FEI_S		BIT(18)
+#define UNICAM_LCI_S		BIT(19)
+#define UNICAM_BUF0_RDY		BIT(20)
+#define UNICAM_BUF0_NO		BIT(21)
+#define UNICAM_BUF1_RDY		BIT(22)
+#define UNICAM_BUF1_NO		BIT(23)
+#define UNICAM_DI		BIT(24)
+
+#define UNICAM_STA_MASK_ALL \
+		(UNICAM_DL | \
+		UNICAM_SBE | \
+		UNICAM_PBE | \
+		UNICAM_HOE | \
+		UNICAM_PLE | \
+		UNICAM_SSC | \
+		UNICAM_CRCE | \
+		UNICAM_IFO | \
+		UNICAM_OFO | \
+		UNICAM_PS | \
+		UNICAM_PI0 | \
+		UNICAM_PI1)
+
+/* UNICAM_ANA Register */
+#define UNICAM_APD		BIT(0)
+#define UNICAM_BPD		BIT(1)
+#define UNICAM_AR		BIT(2)
+#define UNICAM_DDL		BIT(3)
+#define UNICAM_CTATADJ_MASK	GENMASK(7, 4)
+#define UNICAM_PTATADJ_MASK	GENMASK(11, 8)
+
+/* UNICAM_PRI Register */
+#define UNICAM_PE		BIT(0)
+#define UNICAM_PT_MASK		GENMASK(2, 1)
+#define UNICAM_NP_MASK		GENMASK(7, 4)
+#define UNICAM_PP_MASK		GENMASK(11, 8)
+#define UNICAM_BS_MASK		GENMASK(15, 12)
+#define UNICAM_BL_MASK		GENMASK(17, 16)
+
+/* UNICAM_CLK Register */
+#define UNICAM_CLE		BIT(0)
+#define UNICAM_CLPD		BIT(1)
+#define UNICAM_CLLPE		BIT(2)
+#define UNICAM_CLHSE		BIT(3)
+#define UNICAM_CLTRE		BIT(4)
+#define UNICAM_CLAC_MASK	GENMASK(8, 5)
+#define UNICAM_CLSTE		BIT(29)
+
+/* UNICAM_CLT Register */
+#define UNICAM_CLT1_MASK	GENMASK(7, 0)
+#define UNICAM_CLT2_MASK	GENMASK(15, 8)
+
+/* UNICAM_DATn Registers */
+#define UNICAM_DLE		BIT(0)
+#define UNICAM_DLPD		BIT(1)
+#define UNICAM_DLLPE		BIT(2)
+#define UNICAM_DLHSE		BIT(3)
+#define UNICAM_DLTRE		BIT(4)
+#define UNICAM_DLSM		BIT(5)
+#define UNICAM_DLFO		BIT(28)
+#define UNICAM_DLSTE		BIT(29)
+
+#define UNICAM_DAT_MASK_ALL	(UNICAM_DLSTE | UNICAM_DLFO)
+
+/* UNICAM_DLT Register */
+#define UNICAM_DLT1_MASK	GENMASK(7, 0)
+#define UNICAM_DLT2_MASK	GENMASK(15, 8)
+#define UNICAM_DLT3_MASK	GENMASK(23, 16)
+
+/* UNICAM_ICTL Register */
+#define UNICAM_FSIE		BIT(0)
+#define UNICAM_FEIE		BIT(1)
+#define UNICAM_IBOB		BIT(2)
+#define UNICAM_FCM		BIT(3)
+#define UNICAM_TFC		BIT(4)
+#define UNICAM_LIP_MASK		GENMASK(6, 5)
+#define UNICAM_LCIE_MASK	GENMASK(28, 16)
+
+/* UNICAM_IDI0/1 Register */
+#define UNICAM_ID0_MASK		GENMASK(7, 0)
+#define UNICAM_ID1_MASK		GENMASK(15, 8)
+#define UNICAM_ID2_MASK		GENMASK(23, 16)
+#define UNICAM_ID3_MASK		GENMASK(31, 24)
+
+/* UNICAM_ISTA Register */
+#define UNICAM_FSI		BIT(0)
+#define UNICAM_FEI		BIT(1)
+#define UNICAM_LCI		BIT(2)
+
+#define UNICAM_ISTA_MASK_ALL	(UNICAM_FSI | UNICAM_FEI | UNICAM_LCI)
+
+/* UNICAM_IPIPE Register */
+#define UNICAM_PUM_MASK		GENMASK(2, 0)
+/* Unpacking modes */
+#define UNICAM_PUM_NONE		0
+#define UNICAM_PUM_UNPACK6	1
+#define UNICAM_PUM_UNPACK7	2
+#define UNICAM_PUM_UNPACK8	3
+#define UNICAM_PUM_UNPACK10	4
+#define UNICAM_PUM_UNPACK12	5
+#define UNICAM_PUM_UNPACK14	6
+#define UNICAM_PUM_UNPACK16	7
+#define UNICAM_DDM_MASK		GENMASK(6, 3)
+#define UNICAM_PPM_MASK		GENMASK(9, 7)
+/* Packing modes */
+#define UNICAM_PPM_NONE		0
+#define UNICAM_PPM_PACK8	1
+#define UNICAM_PPM_PACK10	2
+#define UNICAM_PPM_PACK12	3
+#define UNICAM_PPM_PACK14	4
+#define UNICAM_PPM_PACK16	5
+#define UNICAM_DEM_MASK		GENMASK(11, 10)
+#define UNICAM_DEBL_MASK	GENMASK(14, 12)
+#define UNICAM_ICM_MASK		GENMASK(16, 15)
+#define UNICAM_IDM_MASK		GENMASK(17, 17)
+
+/* UNICAM_ICC Register */
+#define UNICAM_ICFL_MASK	GENMASK(4, 0)
+#define UNICAM_ICFH_MASK	GENMASK(9, 5)
+#define UNICAM_ICST_MASK	GENMASK(12, 10)
+#define UNICAM_ICLT_MASK	GENMASK(15, 13)
+#define UNICAM_ICLL_MASK	GENMASK(31, 16)
+
+/* UNICAM_DCS Register */
+#define UNICAM_DIE		BIT(0)
+#define UNICAM_DIM		BIT(1)
+#define UNICAM_DBOB		BIT(3)
+#define UNICAM_FDE		BIT(4)
+#define UNICAM_LDP		BIT(5)
+#define UNICAM_EDL_MASK		GENMASK(15, 8)
+
+/* UNICAM_DBCTL Register */
+#define UNICAM_DBEN		BIT(0)
+#define UNICAM_BUF0_IE		BIT(1)
+#define UNICAM_BUF1_IE		BIT(2)
+
+/* UNICAM_CMP[0,1] register */
+#define UNICAM_PCE		BIT(31)
+#define UNICAM_GI		BIT(9)
+#define UNICAM_CPH		BIT(8)
+#define UNICAM_PCVC_MASK	GENMASK(7, 6)
+#define UNICAM_PCDT_MASK	GENMASK(5, 0)
+
+/* UNICAM_MISC register */
+#define UNICAM_FL0		BIT(6)
+#define UNICAM_FL1		BIT(9)
+
+#endif
diff --git a/drivers/media/platform/broadcom/bcm2835-unicam.c b/drivers/media/platform/broadcom/bcm2835-unicam.c
new file mode 100644
index 000000000000..716c89b8a217
--- /dev/null
+++ b/drivers/media/platform/broadcom/bcm2835-unicam.c
@@ -0,0 +1,2607 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * BCM283x / BCM271x Unicam Capture Driver
+ *
+ * Copyright (C) 2017-2020 - Raspberry Pi (Trading) Ltd.
+ *
+ * Dave Stevenson <[e-mail]>
+ *
+ * Based on TI am437x driver by
+ *   Benoit Parrot <[e-mail]>
+ *   Lad, Prabhakar <[e-mail]>
+ *
+ * and TI CAL camera interface driver by
+ *    Benoit Parrot <[e-mail]>
+ *
+ *
+ * There are two camera drivers in the kernel for BCM283x - this one and
+ * bcm2835-camera (currently in staging).
+ *
+ * This driver directly controls the Unicam peripheral - there is no
+ * involvement with the VideoCore firmware. Unicam receives CSI-2 or CCP2 data
+ * and writes it into SDRAM. The only potential processing options are to
+ * repack Bayer data into an alternate format, and applying windowing. The
+ * repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P to
+ * V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12, but
+ * not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both formats
+ * where the relevant formats are defined, and will automatically configure the
+ * repacking as required. Support for windowing may be added later.
+ *
+ * It should be possible to connect this driver to any sensor with a suitable
+ * output interface and V4L2 subdevice driver.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-async.h>
+#include <media/v4l2-common.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-mc.h>
+#include <media/videobuf2-dma-contig.h>
+
+#include "bcm2835-unicam-regs.h"
+
+#define UNICAM_MODULE_NAME		"unicam"
+
+/*
+ * Unicam must request a minimum of 250Mhz from the VPU clock.
+ * Otherwise the input FIFOs overrun and cause image corruption.
+ */
+#define UNICAM_MIN_VPU_CLOCK_RATE	(250 * 1000 * 1000)
+
+/* Unicam has an internal DMA alignment constraint of 16 bytes for each line. */
+#define UNICAM_DMA_BPL_ALIGNMENT	16
+
+/*
+ * The image stride is stored in a 16 bit register, and needs to be aligned to
+ * the DMA constraint. As the ISP in the same SoC has a 32 bytes alignment
+ * constraint on its input, set the image stride alignment to 32 bytes here as
+ * well to avoid incompatible configurations.
+ */
+#define UNICAM_IMAGE_BPL_ALIGNMENT	32
+#define UNICAM_IMAGE_MAX_BPL		((1 << 16) - UNICAM_IMAGE_BPL_ALIGNMENT)
+
+/*
+ * Max width is therefore determined by the max stride divided by the number of
+ * bits per pixel. Take 32bpp as a worst case. No imposed limit on the height,
+ * so adopt a square image for want of anything better.
+ */
+#define UNICAM_IMAGE_MIN_WIDTH		16
+#define UNICAM_IMAGE_MIN_HEIGHT		16
+#define UNICAM_IMAGE_MAX_WIDTH		(UNICAM_IMAGE_MAX_BPL / 4)
+#define UNICAM_IMAGE_MAX_HEIGHT		UNICAM_IMAGE_MAX_WIDTH
+
+/*
+ * There's no intrinsic limits on the width and height for embedded dat. Use
+ * the same maximum values as for the image, to avoid overflows in the image
+ * size computation.
+ */
+#define UNICAM_META_MIN_WIDTH		1
+#define UNICAM_META_MIN_HEIGHT		1
+#define UNICAM_META_MAX_WIDTH		UNICAM_IMAGE_MAX_WIDTH
+#define UNICAM_META_MAX_HEIGHT		UNICAM_IMAGE_MAX_HEIGHT
+
+/*
+ * Size of the dummy buffer. Can be any size really, but the DMA
+ * allocation works in units of page sizes.
+ */
+#define UNICAM_DUMMY_BUF_SIZE		PAGE_SIZE
+
+#define UNICAM_SD_PAD_SINK		0
+#define UNICAM_SD_PAD_SOURCE_IMAGE	1
+#define UNICAM_SD_PAD_SOURCE_METADATA	2
+#define UNICAM_SD_NUM_PADS		(1 + UNICAM_SD_PAD_SOURCE_METADATA)
+
+enum unicam_node_type {
+	UNICAM_IMAGE_NODE,
+	UNICAM_METADATA_NODE,
+	UNICAM_MAX_NODES
+};
+
+/*
+ * struct unicam_format_info - Unicam media bus format information
+ * @fourcc: V4L2 pixel format FCC identifier. 0 if n/a.
+ * @unpacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
+ * out to 16bpp. 0 if n/a.
+ * @code: V4L2 media bus format code.
+ * @depth: Bits per pixel as delivered from the source.
+ * @csi_dt: CSI data type.
+ * @metadata_fmt: This format only applies to the metadata pad.
+ */
+struct unicam_format_info {
+	u32	fourcc;
+	u32	unpacked_fourcc;
+	u32	code;
+	u8	depth;
+	u8	csi_dt;
+	bool	metadata_fmt;
+};
+
+struct unicam_buffer {
+	struct vb2_v4l2_buffer vb;
+	struct list_head list;
+	dma_addr_t dma_addr;
+	unsigned int size;
+};
+
+static inline struct unicam_buffer *to_unicam_buffer(struct vb2_buffer *vb)
+{
+	return container_of(vb, struct unicam_buffer, vb.vb2_buf);
+}
+
+struct unicam_node {
+	bool registered;
+	bool streaming;
+	unsigned int id;
+
+	/* Pointer to the current v4l2_buffer */
+	struct unicam_buffer *cur_frm;
+	/* Pointer to the next v4l2_buffer */
+	struct unicam_buffer *next_frm;
+	/* video capture */
+	const struct unicam_format_info *fmtinfo;
+	/* Used to store current pixel format */
+	struct v4l2_format fmt;
+	/* Buffer queue used in video-buf */
+	struct vb2_queue buffer_queue;
+	/* Queue of filled frames */
+	struct list_head dma_queue;
+	/* IRQ lock for DMA queue */
+	spinlock_t dma_queue_lock;
+	/* lock used to access this structure */
+	struct mutex lock;
+	/* Identifies video device for this channel */
+	struct video_device video_dev;
+	/* Pointer to the parent handle */
+	struct unicam_device *dev;
+	struct media_pad pad;
+	/*
+	 * Dummy buffer intended to be used by unicam
+	 * if we have no other queued buffers to swap to.
+	 */
+	struct unicam_buffer dummy_buf;
+	void *dummy_buf_cpu_addr;
+};
+
+struct unicam_device {
+	struct kref kref;
+
+	/* peripheral base address */
+	void __iomem *base;
+	/* clock gating base address */
+	void __iomem *clk_gate_base;
+	/* lp clock handle */
+	struct clk *clock;
+	/* vpu clock handle */
+	struct clk *vpu_clock;
+	/* V4l2 device */
+	struct v4l2_device v4l2_dev;
+	struct media_device mdev;
+
+	/* parent device */
+	struct device *dev;
+	/* subdevice async Notifier */
+	struct v4l2_async_notifier notifier;
+	unsigned int sequence;
+
+	/* Sensor node */
+	struct {
+		struct v4l2_subdev *subdev;
+		struct media_pad *pad;
+	} sensor;
+
+	/* Internal subdev */
+	struct {
+		struct v4l2_subdev sd;
+		struct media_pad pads[UNICAM_SD_NUM_PADS];
+		bool streaming;
+	} subdev;
+
+	enum v4l2_mbus_type bus_type;
+	/*
+	 * Stores bus.mipi_csi2.flags for CSI2 sensors, or
+	 * bus.mipi_csi1.strobe for CCP2.
+	 */
+	unsigned int bus_flags;
+	unsigned int max_data_lanes;
+	unsigned int active_data_lanes;
+
+	struct media_pipeline pipe;
+
+	struct unicam_node node[UNICAM_MAX_NODES];
+};
+
+static inline struct unicam_device *
+notifier_to_unicam_device(struct v4l2_async_notifier *notifier)
+{
+	return container_of(notifier, struct unicam_device, notifier);
+}
+
+static inline struct unicam_device *
+sd_to_unicam_device(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct unicam_device, subdev.sd);
+}
+
+static void unicam_release(struct kref *kref)
+{
+	struct unicam_device *unicam =
+		container_of(kref, struct unicam_device, kref);
+
+	if (unicam->mdev.dev)
+		media_device_cleanup(&unicam->mdev);
+
+	kfree(unicam);
+}
+
+static struct unicam_device *unicam_get(struct unicam_device *unicam)
+{
+	kref_get(&unicam->kref);
+	return unicam;
+}
+
+static void unicam_put(struct unicam_device *unicam)
+{
+	kref_put(&unicam->kref, unicam_release);
+}
+
+/* -----------------------------------------------------------------------------
+ * Misc helper functions
+ */
+
+static inline bool unicam_sd_pad_is_source(u32 pad)
+{
+	/* Camera RX has 1 sink pad, and N source pads */
+	return pad != UNICAM_SD_PAD_SINK;
+}
+
+static inline bool is_metadata_node(struct unicam_node *node)
+{
+	return node->video_dev.device_caps & V4L2_CAP_META_CAPTURE;
+}
+
+static inline bool is_image_node(struct unicam_node *node)
+{
+	return node->video_dev.device_caps & V4L2_CAP_VIDEO_CAPTURE;
+}
+
+/* -----------------------------------------------------------------------------
+ * Format data table and helper functions
+ */
+
+static const struct v4l2_mbus_framefmt unicam_default_image_format = {
+	.width = 640,
+	.height = 480,
+	.code = MEDIA_BUS_FMT_UYVY8_1X16,
+	.field = V4L2_FIELD_NONE,
+	.colorspace = V4L2_COLORSPACE_SRGB,
+	.ycbcr_enc = V4L2_YCBCR_ENC_601,
+	.quantization = V4L2_QUANTIZATION_LIM_RANGE,
+	.xfer_func = V4L2_XFER_FUNC_SRGB,
+	.flags = 0,
+};
+
+static const struct v4l2_mbus_framefmt unicam_default_meta_format = {
+	.width = 640,
+	.height = 2,
+	.code = MEDIA_BUS_FMT_META_8,
+	.field = V4L2_FIELD_NONE,
+};
+
+static const struct unicam_format_info unicam_image_formats[] = {
+	/* YUV Formats */
+	{
+		.fourcc		= V4L2_PIX_FMT_YUYV,
+		.code		= MEDIA_BUS_FMT_YUYV8_1X16,
+		.depth		= 16,
+		.csi_dt		= 0x1e,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_UYVY,
+		.code		= MEDIA_BUS_FMT_UYVY8_1X16,
+		.depth		= 16,
+		.csi_dt		= 0x1e,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_YVYU,
+		.code		= MEDIA_BUS_FMT_YVYU8_1X16,
+		.depth		= 16,
+		.csi_dt		= 0x1e,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_VYUY,
+		.code		= MEDIA_BUS_FMT_VYUY8_1X16,
+		.depth		= 16,
+		.csi_dt		= 0x1e,
+	}, {
+	/* RGB Formats */
+		.fourcc		= V4L2_PIX_FMT_RGB565, /* gggbbbbb rrrrrggg */
+		.code		= MEDIA_BUS_FMT_RGB565_1X16,
+		.depth		= 16,
+		.csi_dt		= 0x22,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_RGB24, /* rgb */
+		.code		= MEDIA_BUS_FMT_RGB888_1X24,
+		.depth		= 24,
+		.csi_dt		= 0x24,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_BGR24, /* bgr */
+		.code		= MEDIA_BUS_FMT_BGR888_1X24,
+		.depth		= 24,
+		.csi_dt		= 0x24,
+	}, {
+	/* Bayer Formats */
+		.fourcc		= V4L2_PIX_FMT_SBGGR8,
+		.code		= MEDIA_BUS_FMT_SBGGR8_1X8,
+		.depth		= 8,
+		.csi_dt		= 0x2a,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGBRG8,
+		.code		= MEDIA_BUS_FMT_SGBRG8_1X8,
+		.depth		= 8,
+		.csi_dt		= 0x2a,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGRBG8,
+		.code		= MEDIA_BUS_FMT_SGRBG8_1X8,
+		.depth		= 8,
+		.csi_dt		= 0x2a,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SRGGB8,
+		.code		= MEDIA_BUS_FMT_SRGGB8_1X8,
+		.depth		= 8,
+		.csi_dt		= 0x2a,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SBGGR10P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR10,
+		.code		= MEDIA_BUS_FMT_SBGGR10_1X10,
+		.depth		= 10,
+		.csi_dt		= 0x2b,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGBRG10P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG10,
+		.code		= MEDIA_BUS_FMT_SGBRG10_1X10,
+		.depth		= 10,
+		.csi_dt		= 0x2b,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGRBG10P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG10,
+		.code		= MEDIA_BUS_FMT_SGRBG10_1X10,
+		.depth		= 10,
+		.csi_dt		= 0x2b,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SRGGB10P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB10,
+		.code		= MEDIA_BUS_FMT_SRGGB10_1X10,
+		.depth		= 10,
+		.csi_dt		= 0x2b,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SBGGR12P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR12,
+		.code		= MEDIA_BUS_FMT_SBGGR12_1X12,
+		.depth		= 12,
+		.csi_dt		= 0x2c,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGBRG12P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG12,
+		.code		= MEDIA_BUS_FMT_SGBRG12_1X12,
+		.depth		= 12,
+		.csi_dt		= 0x2c,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGRBG12P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG12,
+		.code		= MEDIA_BUS_FMT_SGRBG12_1X12,
+		.depth		= 12,
+		.csi_dt		= 0x2c,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SRGGB12P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB12,
+		.code		= MEDIA_BUS_FMT_SRGGB12_1X12,
+		.depth		= 12,
+		.csi_dt		= 0x2c,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SBGGR14P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SBGGR14,
+		.code		= MEDIA_BUS_FMT_SBGGR14_1X14,
+		.depth		= 14,
+		.csi_dt		= 0x2d,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGBRG14P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SGBRG14,
+		.code		= MEDIA_BUS_FMT_SGBRG14_1X14,
+		.depth		= 14,
+		.csi_dt		= 0x2d,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SGRBG14P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SGRBG14,
+		.code		= MEDIA_BUS_FMT_SGRBG14_1X14,
+		.depth		= 14,
+		.csi_dt		= 0x2d,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_SRGGB14P,
+		.unpacked_fourcc = V4L2_PIX_FMT_SRGGB14,
+		.code		= MEDIA_BUS_FMT_SRGGB14_1X14,
+		.depth		= 14,
+		.csi_dt		= 0x2d,
+	}, {
+	/* 16 bit Bayer formats could be supported. */
+
+	/* Greyscale formats */
+		.fourcc		= V4L2_PIX_FMT_GREY,
+		.code		= MEDIA_BUS_FMT_Y8_1X8,
+		.depth		= 8,
+		.csi_dt		= 0x2a,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_Y10P,
+		.unpacked_fourcc = V4L2_PIX_FMT_Y10,
+		.code		= MEDIA_BUS_FMT_Y10_1X10,
+		.depth		= 10,
+		.csi_dt		= 0x2b,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_Y12P,
+		.unpacked_fourcc = V4L2_PIX_FMT_Y12,
+		.code		= MEDIA_BUS_FMT_Y12_1X12,
+		.depth		= 12,
+		.csi_dt		= 0x2c,
+	}, {
+		.fourcc		= V4L2_PIX_FMT_Y14P,
+		.unpacked_fourcc = V4L2_PIX_FMT_Y14,
+		.code		= MEDIA_BUS_FMT_Y14_1X14,
+		.depth		= 14,
+		.csi_dt		= 0x2d,
+	},
+};
+
+static const struct unicam_format_info unicam_meta_formats[] = {
+	{
+		.fourcc		= V4L2_META_FMT_GENERIC_8,
+		.code		= MEDIA_BUS_FMT_META_8,
+		.depth		= 8,
+		.metadata_fmt	= true,
+	}, {
+		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_10,
+		.code		= MEDIA_BUS_FMT_META_10,
+		.depth		= 10,
+		.metadata_fmt	= true,
+	}, {
+		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_12,
+		.code		= MEDIA_BUS_FMT_META_12,
+		.depth		= 12,
+		.metadata_fmt	= true,
+	}, {
+		.fourcc		= V4L2_META_FMT_GENERIC_CSI2_14,
+		.code		= MEDIA_BUS_FMT_META_14,
+		.depth		= 14,
+		.metadata_fmt	= true,
+	},
+};
+
+/* Format setup functions */
+static const struct unicam_format_info *
+unicam_find_format_by_code(u32 code, u32 pad)
+{
+	const struct unicam_format_info *formats;
+	unsigned int num_formats;
+	unsigned int i;
+
+	if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
+		formats = unicam_image_formats;
+		num_formats = ARRAY_SIZE(unicam_image_formats);
+	} else {
+		formats = unicam_meta_formats;
+		num_formats = ARRAY_SIZE(unicam_meta_formats);
+	}
+
+	for (i = 0; i < num_formats; i++) {
+		if (formats[i].code == code)
+			return &formats[i];
+	}
+
+	return NULL;
+}
+
+static const struct unicam_format_info *
+unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
+{
+	const struct unicam_format_info *formats;
+	unsigned int num_formats;
+	unsigned int i;
+
+	if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
+		formats = unicam_image_formats;
+		num_formats = ARRAY_SIZE(unicam_image_formats);
+	} else {
+		formats = unicam_meta_formats;
+		num_formats = ARRAY_SIZE(unicam_meta_formats);
+	}
+
+	for (i = 0; i < num_formats; ++i) {
+		if (formats[i].fourcc == fourcc)
+			return &formats[i];
+	}
+
+	return NULL;
+}
+
+static void unicam_calc_image_size_bpl(struct unicam_device *unicam,
+				       const struct unicam_format_info *fmtinfo,
+				       struct v4l2_pix_format *pix)
+{
+	u32 min_bpl;
+
+	v4l_bound_align_image(&pix->width, UNICAM_IMAGE_MIN_WIDTH,
+			      UNICAM_IMAGE_MAX_WIDTH, 2,
+			      &pix->height, UNICAM_IMAGE_MIN_HEIGHT,
+			      UNICAM_IMAGE_MAX_HEIGHT, 0, 0);
+
+	/* Unpacking always goes to 16bpp */
+	if (pix->pixelformat == fmtinfo->unpacked_fourcc)
+		min_bpl = pix->width * 2;
+	else
+		min_bpl = pix->width * fmtinfo->depth / 8;
+	min_bpl = ALIGN(min_bpl, UNICAM_IMAGE_BPL_ALIGNMENT);
+
+	pix->bytesperline = ALIGN(pix->bytesperline, UNICAM_IMAGE_BPL_ALIGNMENT);
+	pix->bytesperline = clamp_t(unsigned int, pix->bytesperline, min_bpl,
+				    UNICAM_IMAGE_MAX_BPL);
+
+	pix->sizeimage = pix->height * pix->bytesperline;
+}
+
+static void unicam_calc_meta_size_bpl(struct unicam_device *unicam,
+				      const struct unicam_format_info *fmtinfo,
+				      struct v4l2_meta_format *meta)
+{
+	v4l_bound_align_image(&meta->width, UNICAM_META_MIN_WIDTH,
+			      UNICAM_META_MAX_WIDTH, 0,
+			      &meta->height, UNICAM_META_MIN_HEIGHT,
+			      UNICAM_META_MAX_HEIGHT, 0, 0);
+
+	meta->bytesperline = ALIGN(meta->width * fmtinfo->depth / 8,
+				   UNICAM_DMA_BPL_ALIGNMENT);
+	meta->buffersize = meta->height * meta->bytesperline;
+}
+
+/* -----------------------------------------------------------------------------
+ * Hardware handling
+ */
+
+static inline void unicam_clk_write(struct unicam_device *unicam, u32 val)
+{
+	/* Pass the CM_PASSWORD along with the value. */
+	writel(val | 0x5a000000, unicam->clk_gate_base);
+}
+
+static inline u32 unicam_reg_read(struct unicam_device *unicam, u32 offset)
+{
+	return readl(unicam->base + offset);
+}
+
+static inline void unicam_reg_write(struct unicam_device *unicam, u32 offset, u32 val)
+{
+	writel(val, unicam->base + offset);
+}
+
+static inline int unicam_get_field(u32 value, u32 mask)
+{
+	return (value & mask) >> __ffs(mask);
+}
+
+static inline void unicam_set_field(u32 *valp, u32 field, u32 mask)
+{
+	u32 val = *valp;
+
+	val &= ~mask;
+	val |= (field << __ffs(mask)) & mask;
+	*valp = val;
+}
+
+static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offset,
+					  u32 field, u32 mask)
+{
+	u32 val = unicam_reg_read(unicam, offset);
+
+	unicam_set_field(&val, field, mask);
+	unicam_reg_write(unicam, offset, val);
+}
+
+static void unicam_wr_dma_addr(struct unicam_node *node,
+			       struct unicam_buffer *buf)
+{
+	dma_addr_t endaddr = buf->dma_addr + buf->size;
+
+	if (node->id == UNICAM_IMAGE_NODE) {
+		unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
+		unicam_reg_write(node->dev, UNICAM_IBEA0, endaddr);
+	} else {
+		unicam_reg_write(node->dev, UNICAM_DBSA0, buf->dma_addr);
+		unicam_reg_write(node->dev, UNICAM_DBEA0, endaddr);
+	}
+}
+
+static unsigned int unicam_get_lines_done(struct unicam_device *unicam)
+{
+	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
+	unsigned int stride = node->fmt.fmt.pix.bytesperline;
+	struct unicam_buffer *frm = node->cur_frm;
+	dma_addr_t cur_addr;
+
+	if (!frm)
+		return 0;
+
+	cur_addr = unicam_reg_read(unicam, UNICAM_IBWP);
+	return (unsigned int)(cur_addr - frm->dma_addr) / stride;
+}
+
+static void unicam_schedule_next_buffer(struct unicam_node *node)
+{
+	struct unicam_buffer *buf;
+
+	buf = list_first_entry(&node->dma_queue, struct unicam_buffer, list);
+	node->next_frm = buf;
+	list_del(&buf->list);
+
+	unicam_wr_dma_addr(node, buf);
+}
+
+static void unicam_schedule_dummy_buffer(struct unicam_node *node)
+{
+	int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
+
+	dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
+
+	unicam_wr_dma_addr(node, &node->dummy_buf);
+
+	node->next_frm = NULL;
+}
+
+static void unicam_process_buffer_complete(struct unicam_node *node,
+					   unsigned int sequence)
+{
+	node->cur_frm->vb.field = node->fmt.fmt.pix.field;
+	node->cur_frm->vb.sequence = sequence;
+
+	vb2_buffer_done(&node->cur_frm->vb.vb2_buf, VB2_BUF_STATE_DONE);
+}
+
+static void unicam_queue_event_sof(struct unicam_device *unicam)
+{
+	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
+
+	struct v4l2_event event = {
+		.type = V4L2_EVENT_FRAME_SYNC,
+		.u.frame_sync.frame_sequence = unicam->sequence,
+	};
+
+	v4l2_event_queue(&node->video_dev, &event);
+}
+
+static irqreturn_t unicam_isr(int irq, void *dev)
+{
+	struct unicam_device *unicam = dev;
+	unsigned int lines_done = unicam_get_lines_done(dev);
+	unsigned int sequence = unicam->sequence;
+	unsigned int i;
+	u32 ista, sta;
+	bool fe;
+	u64 ts;
+
+	sta = unicam_reg_read(unicam, UNICAM_STA);
+	/* Write value back to clear the interrupts */
+	unicam_reg_write(unicam, UNICAM_STA, sta);
+
+	ista = unicam_reg_read(unicam, UNICAM_ISTA);
+	/* Write value back to clear the interrupts */
+	unicam_reg_write(unicam, UNICAM_ISTA, ista);
+
+	dev_dbg(unicam->dev, "ISR: ISTA: 0x%X, STA: 0x%X, sequence %d, lines done %d\n",
+		ista, sta, sequence, lines_done);
+
+	if (!(sta & (UNICAM_IS | UNICAM_PI0)))
+		return IRQ_HANDLED;
+
+	/*
+	 * Look for either the Frame End interrupt or the Packet Capture status
+	 * to signal a frame end.
+	 */
+	fe = ista & UNICAM_FEI || sta & UNICAM_PI0;
+
+	/*
+	 * We must run the frame end handler first. If we have a valid next_frm
+	 * and we get a simultaneout FE + FS interrupt, running the FS handler
+	 * first would null out the next_frm ptr and we would have lost the
+	 * buffer forever.
+	 */
+	if (fe) {
+		/*
+		 * Ensure we have swapped buffers already as we can't
+		 * stop the peripheral. If no buffer is available, use a
+		 * dummy buffer to dump out frames until we get a new buffer
+		 * to use.
+		 */
+		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
+			if (!unicam->node[i].streaming)
+				continue;
+
+			/*
+			 * If cur_frm == next_frm, it means we have not had
+			 * a chance to swap buffers, likely due to having
+			 * multiple interrupts occurring simultaneously (like FE
+			 * + FS + LS). In this case, we cannot signal the buffer
+			 * as complete, as the HW will reuse that buffer.
+			 */
+			if (unicam->node[i].cur_frm &&
+			    unicam->node[i].cur_frm != unicam->node[i].next_frm)
+				unicam_process_buffer_complete(&unicam->node[i],
+							       sequence);
+			unicam->node[i].cur_frm = unicam->node[i].next_frm;
+		}
+		unicam->sequence++;
+	}
+
+	if (ista & UNICAM_FSI) {
+		/*
+		 * Timestamp is to be when the first data byte was captured,
+		 * aka frame start.
+		 */
+		ts = ktime_get_ns();
+		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
+			if (!unicam->node[i].streaming)
+				continue;
+
+			if (unicam->node[i].cur_frm)
+				unicam->node[i].cur_frm->vb.vb2_buf.timestamp =
+								ts;
+			else
+				dev_dbg(unicam->v4l2_dev.dev,
+					"ISR: [%d] Dropping frame, buffer not available at FS\n",
+					i);
+			/*
+			 * Set the next frame output to go to a dummy frame
+			 * if we have not managed to obtain another frame
+			 * from the queue.
+			 */
+			unicam_schedule_dummy_buffer(&unicam->node[i]);
+		}
+
+		unicam_queue_event_sof(unicam);
+	}
+
+	/*
+	 * Cannot swap buffer at frame end, there may be a race condition
+	 * where the HW does not actually swap it if the new frame has
+	 * already started.
+	 */
+	if (ista & (UNICAM_FSI | UNICAM_LCI) && !fe) {
+		for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
+			if (!unicam->node[i].streaming)
+				continue;
+
+			spin_lock(&unicam->node[i].dma_queue_lock);
+			if (!list_empty(&unicam->node[i].dma_queue) &&
+			    !unicam->node[i].next_frm)
+				unicam_schedule_next_buffer(&unicam->node[i]);
+			spin_unlock(&unicam->node[i].dma_queue_lock);
+		}
+	}
+
+	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
+		/* Switch out of trigger mode if selected */
+		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
+		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
+	}
+	return IRQ_HANDLED;
+}
+
+static void unicam_set_packing_config(struct unicam_device *unicam)
+{
+	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
+	u32 pack, unpack;
+	u32 val;
+
+	if (node->fmt.fmt.pix.pixelformat == node->fmtinfo->fourcc) {
+		unpack = UNICAM_PUM_NONE;
+		pack = UNICAM_PPM_NONE;
+	} else {
+		switch (node->fmtinfo->depth) {
+		case 8:
+			unpack = UNICAM_PUM_UNPACK8;
+			break;
+		case 10:
+			unpack = UNICAM_PUM_UNPACK10;
+			break;
+		case 12:
+			unpack = UNICAM_PUM_UNPACK12;
+			break;
+		case 14:
+			unpack = UNICAM_PUM_UNPACK14;
+			break;
+		case 16:
+			unpack = UNICAM_PUM_UNPACK16;
+			break;
+		default:
+			unpack = UNICAM_PUM_NONE;
+			break;
+		}
+
+		/* Repacking is always to 16bpp */
+		pack = UNICAM_PPM_PACK16;
+	}
+
+	val = 0;
+	unicam_set_field(&val, unpack, UNICAM_PUM_MASK);
+	unicam_set_field(&val, pack, UNICAM_PPM_MASK);
+	unicam_reg_write(unicam, UNICAM_IPIPE, val);
+}
+
+static void unicam_cfg_image_id(struct unicam_device *unicam)
+{
+	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
+
+	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
+		/* CSI2 mode, hardcode VC 0 for now. */
+		unicam_reg_write(unicam, UNICAM_IDI0,
+				 (0 << 6) | node->fmtinfo->csi_dt);
+	} else {
+		/* CCP2 mode */
+		unicam_reg_write(unicam, UNICAM_IDI0,
+				 0x80 | node->fmtinfo->csi_dt);
+	}
+}
+
+static void unicam_enable_ed(struct unicam_device *unicam)
+{
+	u32 val = unicam_reg_read(unicam, UNICAM_DCS);
+
+	unicam_set_field(&val, 2, UNICAM_EDL_MASK);
+	/* Do not wrap at the end of the embedded data buffer */
+	unicam_set_field(&val, 0, UNICAM_DBOB);
+
+	unicam_reg_write(unicam, UNICAM_DCS, val);
+}
+
+static void unicam_start_rx(struct unicam_device *unicam,
+			    struct unicam_buffer *buf)
+{
+	struct unicam_node *node = &unicam->node[UNICAM_IMAGE_NODE];
+	int line_int_freq = node->fmt.fmt.pix.height >> 2;
+	unsigned int i;
+	u32 val;
+
+	if (line_int_freq < 128)
+		line_int_freq = 128;
+
+	/* Enable lane clocks */
+	val = 1;
+	for (i = 0; i < unicam->active_data_lanes; i++)
+		val = val << 2 | 1;
+	unicam_clk_write(unicam, val);
+
+	/* Basic init */
+	unicam_reg_write(unicam, UNICAM_CTRL, UNICAM_MEM);
+
+	/* Enable analogue control, and leave in reset. */
+	val = UNICAM_AR;
+	unicam_set_field(&val, 7, UNICAM_CTATADJ_MASK);
+	unicam_set_field(&val, 7, UNICAM_PTATADJ_MASK);
+	unicam_reg_write(unicam, UNICAM_ANA, val);
+	usleep_range(1000, 2000);
+
+	/* Come out of reset */
+	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_AR);
+
+	/* Peripheral reset */
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
+
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
+
+	/* Enable Rx control. */
+	val = unicam_reg_read(unicam, UNICAM_CTRL);
+	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
+		unicam_set_field(&val, UNICAM_CPM_CSI2, UNICAM_CPM_MASK);
+		unicam_set_field(&val, UNICAM_DCM_STROBE, UNICAM_DCM_MASK);
+	} else {
+		unicam_set_field(&val, UNICAM_CPM_CCP2, UNICAM_CPM_MASK);
+		unicam_set_field(&val, unicam->bus_flags, UNICAM_DCM_MASK);
+	}
+	/* Packet framer timeout */
+	unicam_set_field(&val, 0xf, UNICAM_PFT_MASK);
+	unicam_set_field(&val, 128, UNICAM_OET_MASK);
+	unicam_reg_write(unicam, UNICAM_CTRL, val);
+
+	unicam_reg_write(unicam, UNICAM_IHWIN, 0);
+	unicam_reg_write(unicam, UNICAM_IVWIN, 0);
+
+	/* AXI bus access QoS setup */
+	val = unicam_reg_read(unicam, UNICAM_PRI);
+	unicam_set_field(&val, 0, UNICAM_BL_MASK);
+	unicam_set_field(&val, 0, UNICAM_BS_MASK);
+	unicam_set_field(&val, 0xe, UNICAM_PP_MASK);
+	unicam_set_field(&val, 8, UNICAM_NP_MASK);
+	unicam_set_field(&val, 2, UNICAM_PT_MASK);
+	unicam_set_field(&val, 1, UNICAM_PE);
+	unicam_reg_write(unicam, UNICAM_PRI, val);
+
+	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
+
+	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
+	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
+	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
+	unicam_reg_write(unicam, UNICAM_ICTL, val);
+	unicam_reg_write(unicam, UNICAM_STA, UNICAM_STA_MASK_ALL);
+	unicam_reg_write(unicam, UNICAM_ISTA, UNICAM_ISTA_MASK_ALL);
+
+	/* tclk_term_en */
+	unicam_reg_write_field(unicam, UNICAM_CLT, 2, UNICAM_CLT1_MASK);
+	/* tclk_settle */
+	unicam_reg_write_field(unicam, UNICAM_CLT, 6, UNICAM_CLT2_MASK);
+	/* td_term_en */
+	unicam_reg_write_field(unicam, UNICAM_DLT, 2, UNICAM_DLT1_MASK);
+	/* ths_settle */
+	unicam_reg_write_field(unicam, UNICAM_DLT, 6, UNICAM_DLT2_MASK);
+	/* trx_enable */
+	unicam_reg_write_field(unicam, UNICAM_DLT, 0, UNICAM_DLT3_MASK);
+
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_SOE);
+
+	/* Packet compare setup - required to avoid missing frame ends */
+	val = 0;
+	unicam_set_field(&val, 1, UNICAM_PCE);
+	unicam_set_field(&val, 1, UNICAM_GI);
+	unicam_set_field(&val, 1, UNICAM_CPH);
+	unicam_set_field(&val, 0, UNICAM_PCVC_MASK);
+	unicam_set_field(&val, 1, UNICAM_PCDT_MASK);
+	unicam_reg_write(unicam, UNICAM_CMP0, val);
+
+	/* Enable clock lane and set up terminations */
+	val = 0;
+	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
+		/* CSI2 */
+		unicam_set_field(&val, 1, UNICAM_CLE);
+		unicam_set_field(&val, 1, UNICAM_CLLPE);
+		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
+			unicam_set_field(&val, 1, UNICAM_CLTRE);
+			unicam_set_field(&val, 1, UNICAM_CLHSE);
+		}
+	} else {
+		/* CCP2 */
+		unicam_set_field(&val, 1, UNICAM_CLE);
+		unicam_set_field(&val, 1, UNICAM_CLHSE);
+		unicam_set_field(&val, 1, UNICAM_CLTRE);
+	}
+	unicam_reg_write(unicam, UNICAM_CLK, val);
+
+	/*
+	 * Enable required data lanes with appropriate terminations.
+	 * The same value needs to be written to UNICAM_DATn registers for
+	 * the active lanes, and 0 for inactive ones.
+	 */
+	val = 0;
+	if (unicam->bus_type == V4L2_MBUS_CSI2_DPHY) {
+		/* CSI2 */
+		unicam_set_field(&val, 1, UNICAM_DLE);
+		unicam_set_field(&val, 1, UNICAM_DLLPE);
+		if (!(unicam->bus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) {
+			unicam_set_field(&val, 1, UNICAM_DLTRE);
+			unicam_set_field(&val, 1, UNICAM_DLHSE);
+		}
+	} else {
+		/* CCP2 */
+		unicam_set_field(&val, 1, UNICAM_DLE);
+		unicam_set_field(&val, 1, UNICAM_DLHSE);
+		unicam_set_field(&val, 1, UNICAM_DLTRE);
+	}
+	unicam_reg_write(unicam, UNICAM_DAT0, val);
+
+	if (unicam->active_data_lanes == 1)
+		val = 0;
+	unicam_reg_write(unicam, UNICAM_DAT1, val);
+
+	if (unicam->max_data_lanes > 2) {
+		/*
+		 * Registers UNICAM_DAT2 and UNICAM_DAT3 only valid if the
+		 * instance supports more than 2 data lanes.
+		 */
+		if (unicam->active_data_lanes == 2)
+			val = 0;
+		unicam_reg_write(unicam, UNICAM_DAT2, val);
+
+		if (unicam->active_data_lanes == 3)
+			val = 0;
+		unicam_reg_write(unicam, UNICAM_DAT3, val);
+	}
+
+	unicam_reg_write(unicam, UNICAM_IBLS,
+			 node->fmt.fmt.pix.bytesperline);
+	unicam_wr_dma_addr(&unicam->node[UNICAM_IMAGE_NODE], buf);
+	unicam_set_packing_config(unicam);
+	unicam_cfg_image_id(unicam);
+
+	val = unicam_reg_read(unicam, UNICAM_MISC);
+	unicam_set_field(&val, 1, UNICAM_FL0);
+	unicam_set_field(&val, 1, UNICAM_FL1);
+	unicam_reg_write(unicam, UNICAM_MISC, val);
+
+	/* Enable peripheral */
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPE);
+
+	/* Load image pointers */
+	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_LIP_MASK);
+
+	/*
+	 * Enable trigger only for the first frame to
+	 * sync correctly to the FS from the source.
+	 */
+	unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
+}
+
+static void unicam_start_metadata(struct unicam_device *unicam,
+				  struct unicam_buffer *buf)
+{
+	struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
+
+	unicam_enable_ed(unicam);
+	unicam_wr_dma_addr(node, buf);
+	unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
+}
+
+static void unicam_disable(struct unicam_device *unicam)
+{
+	/* Analogue lane control disable */
+	unicam_reg_write_field(unicam, UNICAM_ANA, 1, UNICAM_DDL);
+
+	/* Stop the output engine */
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_SOE);
+
+	/* Disable the data lanes. */
+	unicam_reg_write(unicam, UNICAM_DAT0, 0);
+	unicam_reg_write(unicam, UNICAM_DAT1, 0);
+
+	if (unicam->max_data_lanes > 2) {
+		unicam_reg_write(unicam, UNICAM_DAT2, 0);
+		unicam_reg_write(unicam, UNICAM_DAT3, 0);
+	}
+
+	/* Peripheral reset */
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 1, UNICAM_CPR);
+	usleep_range(50, 100);
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPR);
+
+	/* Disable peripheral */
+	unicam_reg_write_field(unicam, UNICAM_CTRL, 0, UNICAM_CPE);
+
+	/* Clear ED setup */
+	unicam_reg_write(unicam, UNICAM_DCS, 0);
+
+	/* Disable all lane clocks */
+	unicam_clk_write(unicam, 0);
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 subdev operations
+ */
+
+static int __unicam_subdev_set_routing(struct v4l2_subdev *sd,
+				       struct v4l2_subdev_state *state,
+				       struct v4l2_subdev_krouting *routing)
+{
+	struct v4l2_subdev_route *route;
+	int ret;
+
+	ret = v4l2_subdev_routing_validate(sd, routing,
+					   V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
+	if (ret)
+		return ret;
+
+	ret = v4l2_subdev_set_routing(sd, state, routing);
+	if (ret)
+		return ret;
+
+	for_each_active_route(&state->routing, route) {
+		const struct v4l2_mbus_framefmt *def_fmt;
+		struct v4l2_mbus_framefmt *fmt;
+
+		if (route->source_pad == UNICAM_SD_PAD_SOURCE_IMAGE)
+			def_fmt = &unicam_default_image_format;
+		else
+			def_fmt = &unicam_default_meta_format;
+
+		fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
+						   route->sink_stream);
+		*fmt = *def_fmt;
+		fmt = v4l2_subdev_state_get_format(state, route->source_pad,
+						   route->source_stream);
+		*fmt = *def_fmt;
+	}
+
+	return 0;
+}
+
+static int unicam_subdev_init_state(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_state *state)
+{
+	struct v4l2_subdev_route routes[] = {
+		{
+			.sink_pad = UNICAM_SD_PAD_SINK,
+			.sink_stream = 0,
+			.source_pad = UNICAM_SD_PAD_SOURCE_IMAGE,
+			.source_stream = 0,
+			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+		},
+	};
+
+	struct v4l2_subdev_krouting routing = {
+		.len_routes = ARRAY_SIZE(routes),
+		.num_routes = ARRAY_SIZE(routes),
+		.routes = routes,
+	};
+
+	/* Initialize routing to single route to the fist source pad. */
+	return __unicam_subdev_set_routing(sd, state, &routing);
+}
+
+static int unicam_subdev_enum_mbus_code(struct v4l2_subdev *sd,
+					struct v4l2_subdev_state *state,
+					struct v4l2_subdev_mbus_code_enum *code)
+{
+	u32 pad, stream;
+	int ret;
+
+	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
+						    code->pad, code->stream,
+						    &pad, &stream);
+	if (ret)
+		return ret;
+
+	if (unicam_sd_pad_is_source(code->pad)) {
+		/* No transcoding, source and sink codes must match. */
+		const struct v4l2_mbus_framefmt *fmt;
+
+		fmt = v4l2_subdev_state_get_format(state, pad, stream);
+		if (!fmt)
+			return -EINVAL;
+
+		if (code->index > 0)
+			return -EINVAL;
+
+		code->code = fmt->code;
+	} else {
+		const struct unicam_format_info *formats;
+		unsigned int num_formats;
+
+		if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
+			formats = unicam_image_formats;
+			num_formats = ARRAY_SIZE(unicam_image_formats);
+		} else {
+			formats = unicam_meta_formats;
+			num_formats = ARRAY_SIZE(unicam_meta_formats);
+		}
+
+		if (code->index >= num_formats)
+			return -EINVAL;
+
+		code->code = formats[code->index].code;
+	}
+
+	return 0;
+}
+
+static int unicam_subdev_enum_frame_size(struct v4l2_subdev *sd,
+					 struct v4l2_subdev_state *state,
+					 struct v4l2_subdev_frame_size_enum *fse)
+{
+	u32 pad, stream;
+	int ret;
+
+	if (fse->index > 0)
+		return -EINVAL;
+
+	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, fse->pad,
+						    fse->stream, &pad,
+						    &stream);
+	if (ret)
+		return ret;
+
+	if (unicam_sd_pad_is_source(fse->pad)) {
+		/* No transcoding, source and sink formats must match. */
+		const struct v4l2_mbus_framefmt *fmt;
+
+		fmt = v4l2_subdev_state_get_format(state, pad, stream);
+		if (!fmt)
+			return -EINVAL;
+
+		if (fse->code != fmt->code)
+			return -EINVAL;
+
+		fse->min_width = fmt->width;
+		fse->max_width = fmt->width;
+		fse->min_height = fmt->height;
+		fse->max_height = fmt->height;
+	} else {
+		const struct unicam_format_info *fmtinfo;
+
+		fmtinfo = unicam_find_format_by_code(fse->code, pad);
+		if (!fmtinfo)
+			return -EINVAL;
+
+		if (pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
+			fse->min_width = UNICAM_IMAGE_MIN_WIDTH;
+			fse->max_width = UNICAM_IMAGE_MAX_WIDTH;
+			fse->min_height = UNICAM_IMAGE_MIN_HEIGHT;
+			fse->max_height = UNICAM_IMAGE_MAX_HEIGHT;
+		} else {
+			fse->min_width = UNICAM_META_MIN_WIDTH;
+			fse->max_width = UNICAM_META_MAX_WIDTH;
+			fse->min_height = UNICAM_META_MIN_HEIGHT;
+			fse->max_height = UNICAM_META_MAX_HEIGHT;
+		}
+	}
+
+	return 0;
+}
+
+static int unicam_subdev_set_format(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_state *state,
+				    struct v4l2_subdev_format *format)
+{
+	struct unicam_device *unicam = sd_to_unicam_device(sd);
+	struct v4l2_mbus_framefmt *sink_format, *source_format;
+	const struct unicam_format_info *fmtinfo;
+	u32 source_pad, source_stream;
+	int ret;
+
+	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
+	    unicam->subdev.streaming)
+		return -EBUSY;
+
+	/* No transcoding, source and sink formats must match. */
+	if (unicam_sd_pad_is_source(format->pad))
+		return v4l2_subdev_get_fmt(sd, state, format);
+
+	/*
+	 * Allowed formats for the stream on the sink pad depend on what source
+	 * pad the stream is routed to. Find the corresponding source pad and
+	 * use it to validate the media bus code.
+	 */
+	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
+						    format->pad, format->stream,
+						    &source_pad, &source_stream);
+	if (ret)
+		return ret;
+
+	fmtinfo = unicam_find_format_by_code(format->format.code, source_pad);
+	if (!fmtinfo) {
+		fmtinfo = source_pad == UNICAM_SD_PAD_SOURCE_IMAGE
+			? &unicam_image_formats[0] : &unicam_meta_formats[0];
+		format->format.code = fmtinfo->code;
+	}
+
+	if (source_pad == UNICAM_SD_PAD_SOURCE_IMAGE) {
+		format->format.width = clamp_t(unsigned int,
+					       format->format.width,
+					       UNICAM_IMAGE_MIN_WIDTH,
+					       UNICAM_IMAGE_MAX_WIDTH);
+		format->format.height = clamp_t(unsigned int,
+						format->format.height,
+						UNICAM_IMAGE_MIN_HEIGHT,
+						UNICAM_IMAGE_MAX_HEIGHT);
+		format->format.field = V4L2_FIELD_NONE;
+	} else {
+		format->format.width = clamp_t(unsigned int,
+					       format->format.width,
+					       UNICAM_META_MIN_WIDTH,
+					       UNICAM_META_MAX_WIDTH);
+		format->format.height = clamp_t(unsigned int,
+						format->format.height,
+						UNICAM_META_MIN_HEIGHT,
+						UNICAM_META_MAX_HEIGHT);
+		format->format.field = V4L2_FIELD_NONE;
+
+		/* Colorspace don't apply to metadata. */
+		format->format.colorspace = 0;
+		format->format.ycbcr_enc = 0;
+		format->format.quantization = 0;
+		format->format.xfer_func = 0;
+	}
+
+	sink_format = v4l2_subdev_state_get_format(state, format->pad,
+						   format->stream);
+	source_format = v4l2_subdev_state_get_format(state, source_pad,
+						     source_stream);
+	*sink_format = format->format;
+	*source_format = format->format;
+
+	return 0;
+}
+
+static int unicam_subdev_set_routing(struct v4l2_subdev *sd,
+				     struct v4l2_subdev_state *state,
+				     enum v4l2_subdev_format_whence which,
+				     struct v4l2_subdev_krouting *routing)
+{
+	struct unicam_device *unicam = sd_to_unicam_device(sd);
+
+	if (which == V4L2_SUBDEV_FORMAT_ACTIVE && unicam->subdev.streaming)
+		return -EBUSY;
+
+	return __unicam_subdev_set_routing(sd, state, routing);
+}
+
+static int unicam_sd_enable_streams(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_state *state, u32 pad,
+				    u64 streams_mask)
+{
+	struct unicam_device *unicam = sd_to_unicam_device(sd);
+	u32 other_pad, other_stream;
+	int ret;
+
+	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
+						    &other_pad, &other_stream);
+	if (ret)
+		return ret;
+
+	unicam->sequence = 0;
+
+	ret = v4l2_subdev_enable_streams(unicam->sensor.subdev,
+					 unicam->sensor.pad->index,
+					 BIT(other_stream));
+	if (ret) {
+		dev_err(unicam->dev, "stream on failed in subdev\n");
+		return ret;
+	}
+
+	unicam->subdev.streaming = true;
+
+	return 0;
+}
+
+static int unicam_sd_disable_streams(struct v4l2_subdev *sd,
+				     struct v4l2_subdev_state *state, u32 pad,
+				     u64 streams_mask)
+{
+	struct unicam_device *unicam = sd_to_unicam_device(sd);
+	u32 other_pad, other_stream;
+	int ret;
+
+	ret = v4l2_subdev_routing_find_opposite_end(&state->routing, pad, 0,
+						    &other_pad, &other_stream);
+	if (ret)
+		return ret;
+
+	v4l2_subdev_disable_streams(unicam->sensor.subdev,
+				    unicam->sensor.pad->index,
+				    BIT(other_stream));
+
+	unicam->subdev.streaming = false;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_pad_ops unicam_subdev_pad_ops = {
+	.enum_mbus_code		= unicam_subdev_enum_mbus_code,
+	.enum_frame_size	= unicam_subdev_enum_frame_size,
+	.get_fmt		= v4l2_subdev_get_fmt,
+	.set_fmt		= unicam_subdev_set_format,
+	.set_routing		= unicam_subdev_set_routing,
+	.enable_streams		= unicam_sd_enable_streams,
+	.disable_streams	= unicam_sd_disable_streams,
+};
+
+static const struct v4l2_subdev_ops unicam_subdev_ops = {
+	.pad			= &unicam_subdev_pad_ops,
+};
+
+static const struct v4l2_subdev_internal_ops unicam_subdev_internal_ops = {
+	.init_state		= unicam_subdev_init_state,
+};
+
+static const struct media_entity_operations unicam_subdev_media_ops = {
+	.link_validate		= v4l2_subdev_link_validate,
+	.has_pad_interdep	= v4l2_subdev_has_pad_interdep,
+};
+
+static int unicam_subdev_init(struct unicam_device *unicam)
+{
+	struct v4l2_subdev *sd = &unicam->subdev.sd;
+	int ret;
+
+	v4l2_subdev_init(sd, &unicam_subdev_ops);
+	sd->internal_ops = &unicam_subdev_internal_ops;
+	v4l2_set_subdevdata(sd, unicam);
+
+	sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+	sd->entity.ops = &unicam_subdev_media_ops;
+	sd->dev = unicam->dev;
+	sd->owner = THIS_MODULE;
+	sd->flags = V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
+
+	strscpy(sd->name, "unicam", sizeof(sd->name));
+
+	unicam->subdev.pads[UNICAM_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
+	unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_IMAGE].flags = MEDIA_PAD_FL_SOURCE;
+	unicam->subdev.pads[UNICAM_SD_PAD_SOURCE_METADATA].flags = MEDIA_PAD_FL_SOURCE;
+
+	ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(unicam->subdev.pads),
+				     unicam->subdev.pads);
+	if (ret) {
+		dev_err(unicam->dev, "Failed to initialize media entity: %d\n",
+			ret);
+		return ret;
+	}
+
+	ret = v4l2_subdev_init_finalize(sd);
+	if (ret) {
+		dev_err(unicam->dev, "Failed to initialize subdev: %d\n", ret);
+		goto err_entity;
+	}
+
+	ret = v4l2_device_register_subdev(&unicam->v4l2_dev, sd);
+	if (ret) {
+		dev_err(unicam->dev, "Failed to register subdev: %d\n", ret);
+		goto err_subdev;
+	}
+
+	return 0;
+
+err_subdev:
+	v4l2_subdev_cleanup(sd);
+err_entity:
+	media_entity_cleanup(&sd->entity);
+	return ret;
+}
+
+static void unicam_subdev_cleanup(struct unicam_device *unicam)
+{
+	v4l2_subdev_cleanup(&unicam->subdev.sd);
+	media_entity_cleanup(&unicam->subdev.sd.entity);
+}
+
+/* -----------------------------------------------------------------------------
+ * Videobuf2 queue operations
+ */
+
+static int unicam_queue_setup(struct vb2_queue *vq,
+			      unsigned int *nbuffers,
+			      unsigned int *nplanes,
+			      unsigned int sizes[],
+			      struct device *alloc_devs[])
+{
+	struct unicam_node *node = vb2_get_drv_priv(vq);
+	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
+		 : node->fmt.fmt.meta.buffersize;
+
+	if (vq->num_buffers + *nbuffers < 3)
+		*nbuffers = 3 - vq->num_buffers;
+
+	if (*nplanes) {
+		if (sizes[0] < size) {
+			dev_dbg(node->dev->dev, "sizes[0] %i < size %u\n",
+				sizes[0], size);
+			return -EINVAL;
+		}
+		size = sizes[0];
+	}
+
+	*nplanes = 1;
+	sizes[0] = size;
+
+	return 0;
+}
+
+static int unicam_buffer_prepare(struct vb2_buffer *vb)
+{
+	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
+	struct unicam_buffer *buf = to_unicam_buffer(vb);
+	u32 size = is_image_node(node) ? node->fmt.fmt.pix.sizeimage
+		 : node->fmt.fmt.meta.buffersize;
+
+	if (vb2_plane_size(vb, 0) < size) {
+		dev_dbg(node->dev->dev,
+			"data will not fit into plane (%lu < %u)\n",
+			vb2_plane_size(vb, 0), size);
+		return -EINVAL;
+	}
+
+	buf->dma_addr = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
+	buf->size = size;
+
+	vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
+
+	return 0;
+}
+
+static void unicam_return_buffers(struct unicam_node *node,
+				  enum vb2_buffer_state state)
+{
+	struct unicam_buffer *buf, *tmp;
+
+	list_for_each_entry_safe(buf, tmp, &node->dma_queue, list) {
+		list_del(&buf->list);
+		vb2_buffer_done(&buf->vb.vb2_buf, state);
+	}
+
+	if (node->cur_frm)
+		vb2_buffer_done(&node->cur_frm->vb.vb2_buf,
+				state);
+	if (node->next_frm && node->cur_frm != node->next_frm)
+		vb2_buffer_done(&node->next_frm->vb.vb2_buf,
+				state);
+
+	node->cur_frm = NULL;
+	node->next_frm = NULL;
+}
+
+static int unicam_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct unicam_node *node = vb2_get_drv_priv(vq);
+	struct unicam_device *unicam = node->dev;
+	struct v4l2_subdev_state *state;
+	struct unicam_buffer *buf;
+	unsigned long flags;
+	int ret;
+	u32 pad, stream;
+	u32 remote_pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
+					     : UNICAM_SD_PAD_SOURCE_METADATA;
+
+	/* Look for the route for the given pad and stream. */
+	state = v4l2_subdev_lock_and_get_active_state(&unicam->subdev.sd);
+	ret = v4l2_subdev_routing_find_opposite_end(&state->routing,
+						    remote_pad, 0,
+						    &pad, &stream);
+	v4l2_subdev_unlock_state(state);
+
+	if (ret)
+		goto err_return_buffers;
+
+	dev_dbg(unicam->dev, "Starting stream on %s: %u/%u -> %u/%u (%s)\n",
+		unicam->subdev.sd.name, pad, stream, remote_pad, 0,
+		is_metadata_node(node) ? "metadata" : "image");
+
+	/* The metadata node can't be started alone. */
+	if (is_metadata_node(node)) {
+		if (!unicam->node[UNICAM_IMAGE_NODE].streaming) {
+			dev_err(unicam->dev,
+				"Can't start metadata without image\n");
+			ret = -EINVAL;
+			goto err_return_buffers;
+		}
+
+		spin_lock_irqsave(&node->dma_queue_lock, flags);
+		buf = list_first_entry(&node->dma_queue,
+				       struct unicam_buffer, list);
+		dev_dbg(unicam->dev, "buffer %p\n", buf);
+		node->cur_frm = buf;
+		node->next_frm = buf;
+		list_del(&buf->list);
+		spin_unlock_irqrestore(&node->dma_queue_lock, flags);
+
+		unicam_start_metadata(unicam, buf);
+		node->streaming = true;
+		return 0;
+	}
+
+	ret = pm_runtime_resume_and_get(unicam->dev);
+	if (ret < 0) {
+		dev_err(unicam->dev, "PM runtime resume failed: %d\n", ret);
+		goto err_return_buffers;
+	}
+
+	ret = video_device_pipeline_start(&node->video_dev, &unicam->pipe);
+	if (ret < 0) {
+		dev_dbg(unicam->dev, "Failed to start media pipeline: %d\n", ret);
+		goto err_pm_put;
+	}
+
+	spin_lock_irqsave(&node->dma_queue_lock, flags);
+	buf = list_first_entry(&node->dma_queue,
+			       struct unicam_buffer, list);
+	dev_dbg(unicam->dev, "buffer %p\n", buf);
+	node->cur_frm = buf;
+	node->next_frm = buf;
+	list_del(&buf->list);
+	spin_unlock_irqrestore(&node->dma_queue_lock, flags);
+
+	unicam_start_rx(unicam, buf);
+
+	ret = v4l2_subdev_enable_streams(&unicam->subdev.sd, remote_pad, BIT(0));
+	if (ret < 0) {
+		dev_err(unicam->dev, "stream on failed in subdev\n");
+		goto error_pipeline;
+	}
+
+	node->streaming = true;
+
+	return 0;
+
+error_pipeline:
+	video_device_pipeline_stop(&node->video_dev);
+err_pm_put:
+	pm_runtime_put_sync(unicam->dev);
+err_return_buffers:
+	unicam_return_buffers(node, VB2_BUF_STATE_QUEUED);
+	return ret;
+}
+
+static void unicam_stop_streaming(struct vb2_queue *vq)
+{
+	struct unicam_node *node = vb2_get_drv_priv(vq);
+	struct unicam_device *unicam = node->dev;
+	u32 remote_pad_index = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
+						   : UNICAM_SD_PAD_SOURCE_METADATA;
+
+	node->streaming = false;
+
+	v4l2_subdev_disable_streams(&unicam->subdev.sd, remote_pad_index,
+				    BIT(0));
+
+	/* We can stream only with the image node. */
+	if (is_metadata_node(node)) {
+		/*
+		 * Allow the hardware to spin in the dummy buffer.
+		 * This is only really needed if the embedded data pad is
+		 * disabled before the image pad.
+		 */
+		unicam_wr_dma_addr(node, &node->dummy_buf);
+		goto dequeue_buffers;
+	}
+
+	unicam_disable(unicam);
+
+	video_device_pipeline_stop(&node->video_dev);
+	pm_runtime_put(unicam->dev);
+
+dequeue_buffers:
+	/* Clear all queued buffers for the node */
+	unicam_return_buffers(node, VB2_BUF_STATE_ERROR);
+}
+
+static void unicam_buffer_queue(struct vb2_buffer *vb)
+{
+	struct unicam_node *node = vb2_get_drv_priv(vb->vb2_queue);
+	struct unicam_buffer *buf = to_unicam_buffer(vb);
+
+	spin_lock_irq(&node->dma_queue_lock);
+	list_add_tail(&buf->list, &node->dma_queue);
+	spin_unlock_irq(&node->dma_queue_lock);
+}
+
+static const struct vb2_ops unicam_video_qops = {
+	.queue_setup		= unicam_queue_setup,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+	.buf_prepare		= unicam_buffer_prepare,
+	.start_streaming	= unicam_start_streaming,
+	.stop_streaming		= unicam_stop_streaming,
+	.buf_queue		= unicam_buffer_queue,
+};
+
+/* -----------------------------------------------------------------------------
+ *  V4L2 video device operations
+ */
+
+static int unicam_querycap(struct file *file, void *priv,
+			   struct v4l2_capability *cap)
+{
+	strscpy(cap->driver, UNICAM_MODULE_NAME, sizeof(cap->driver));
+	strscpy(cap->card, UNICAM_MODULE_NAME, sizeof(cap->card));
+
+	cap->capabilities |= V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_META_CAPTURE;
+
+	return 0;
+}
+
+static int unicam_enum_fmt_vid(struct file *file, void  *priv,
+			       struct v4l2_fmtdesc *f)
+{
+	unsigned int index;
+	unsigned int i;
+
+	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_image_formats); i++) {
+		if (f->mbus_code && unicam_image_formats[i].code != f->mbus_code)
+			continue;
+
+		if (index == f->index) {
+			f->pixelformat = unicam_image_formats[i].fourcc;
+			return 0;
+		}
+
+		index++;
+
+		if (!unicam_image_formats[i].unpacked_fourcc)
+			continue;
+
+		if (index == f->index) {
+			f->pixelformat = unicam_image_formats[i].unpacked_fourcc;
+			return 0;
+		}
+
+		index++;
+	}
+
+	return -EINVAL;
+}
+
+static int unicam_g_fmt_vid(struct file *file, void *priv,
+			    struct v4l2_format *f)
+{
+	struct unicam_node *node = video_drvdata(file);
+
+	*f = node->fmt;
+
+	return 0;
+}
+
+static const struct unicam_format_info *
+__unicam_try_fmt_vid(struct unicam_node *node, struct v4l2_pix_format *pix)
+{
+	const struct unicam_format_info *fmtinfo;
+
+	/*
+	 * Default to the first format if the requested pixel format code isn't
+	 * supported.
+	 */
+	fmtinfo = unicam_find_format_by_fourcc(pix->pixelformat,
+					       UNICAM_SD_PAD_SOURCE_IMAGE);
+	if (!fmtinfo) {
+		fmtinfo = &unicam_image_formats[0];
+		pix->pixelformat = fmtinfo->fourcc;
+	}
+
+	unicam_calc_image_size_bpl(node->dev, fmtinfo, pix);
+
+	if (pix->field == V4L2_FIELD_ANY)
+		pix->field = V4L2_FIELD_NONE;
+
+	return fmtinfo;
+}
+
+static int unicam_try_fmt_vid(struct file *file, void *priv,
+			      struct v4l2_format *f)
+{
+	struct unicam_node *node = video_drvdata(file);
+
+	__unicam_try_fmt_vid(node, &f->fmt.pix);
+	return 0;
+}
+
+static int unicam_s_fmt_vid(struct file *file, void *priv,
+			    struct v4l2_format *f)
+{
+	struct unicam_node *node = video_drvdata(file);
+
+	if (vb2_is_busy(&node->buffer_queue))
+		return -EBUSY;
+
+	node->fmtinfo = __unicam_try_fmt_vid(node, &f->fmt.pix);
+	node->fmt = *f;
+
+	return 0;
+}
+
+static int unicam_enum_fmt_meta(struct file *file, void *priv,
+				struct v4l2_fmtdesc *f)
+{
+	unsigned int i, index;
+
+	for (i = 0, index = 0; i < ARRAY_SIZE(unicam_meta_formats); i++) {
+		if (f->mbus_code && unicam_meta_formats[i].code != f->mbus_code)
+			continue;
+		if (!unicam_meta_formats[i].metadata_fmt)
+			continue;
+
+		if (index == f->index) {
+			f->pixelformat = unicam_meta_formats[i].fourcc;
+			f->type = V4L2_BUF_TYPE_META_CAPTURE;
+			return 0;
+		}
+		index++;
+	}
+
+	return -EINVAL;
+}
+
+static int unicam_g_fmt_meta(struct file *file, void *priv,
+			     struct v4l2_format *f)
+{
+	struct unicam_node *node = video_drvdata(file);
+
+	f->fmt.meta = node->fmt.fmt.meta;
+
+	return 0;
+}
+
+static const struct unicam_format_info *
+__unicam_try_fmt_meta(struct unicam_node *node, struct v4l2_meta_format *meta)
+{
+	const struct unicam_format_info *fmtinfo;
+
+	/*
+	 * Default to the first format if the requested pixel format code isn't
+	 * supported.
+	 */
+	fmtinfo = unicam_find_format_by_fourcc(meta->dataformat,
+					       UNICAM_SD_PAD_SOURCE_METADATA);
+	if (!fmtinfo) {
+		fmtinfo = &unicam_meta_formats[0];
+		meta->dataformat = fmtinfo->fourcc;
+	}
+
+	unicam_calc_meta_size_bpl(node->dev, fmtinfo, meta);
+
+	return fmtinfo;
+}
+
+static int unicam_try_fmt_meta(struct file *file, void *priv,
+			       struct v4l2_format *f)
+{
+	struct unicam_node *node = video_drvdata(file);
+
+	__unicam_try_fmt_vid(node, &f->fmt.pix);
+	return 0;
+}
+
+static int unicam_s_fmt_meta(struct file *file, void *priv,
+			     struct v4l2_format *f)
+{
+	struct unicam_node *node = video_drvdata(file);
+
+	if (vb2_is_busy(&node->buffer_queue))
+		return -EBUSY;
+
+	node->fmtinfo = __unicam_try_fmt_meta(node, &f->fmt.meta);
+	node->fmt = *f;
+
+	return 0;
+}
+
+static int unicam_enum_framesizes(struct file *file, void *fh,
+				  struct v4l2_frmsizeenum *fsize)
+{
+	struct unicam_node *node = video_drvdata(file);
+	int ret = -EINVAL;
+
+	if (fsize->index > 0)
+		return ret;
+
+	if (is_image_node(node)) {
+		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
+						  UNICAM_SD_PAD_SOURCE_IMAGE))
+			return ret;
+
+		fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
+		fsize->stepwise.min_width = UNICAM_IMAGE_MIN_WIDTH;
+		fsize->stepwise.max_width = UNICAM_IMAGE_MAX_WIDTH;
+		fsize->stepwise.step_width = 1;
+		fsize->stepwise.min_height = UNICAM_IMAGE_MIN_HEIGHT;
+		fsize->stepwise.max_height = UNICAM_IMAGE_MAX_HEIGHT;
+		fsize->stepwise.step_height = 1;
+	} else {
+		if (!unicam_find_format_by_fourcc(fsize->pixel_format,
+						  UNICAM_SD_PAD_SOURCE_METADATA))
+			return ret;
+
+		fsize->stepwise.min_width = UNICAM_META_MIN_WIDTH;
+		fsize->stepwise.max_width = UNICAM_META_MAX_WIDTH;
+		fsize->stepwise.step_width = 1;
+		fsize->stepwise.min_height = UNICAM_META_MIN_HEIGHT;
+		fsize->stepwise.max_height = UNICAM_META_MAX_HEIGHT;
+		fsize->stepwise.step_height = 1;
+	}
+
+	return 0;
+}
+
+static int unicam_log_status(struct file *file, void *fh)
+{
+	struct unicam_node *node = video_drvdata(file);
+	struct unicam_device *unicam = node->dev;
+	u32 reg;
+
+	/* status for sub devices */
+	v4l2_device_call_all(&unicam->v4l2_dev, 0, core, log_status);
+
+	dev_info(unicam->dev, "-----Receiver status-----\n");
+	dev_info(unicam->dev, "V4L2 width/height:   %ux%u\n",
+		 node->fmt.fmt.pix.width, node->fmt.fmt.pix.height);
+	dev_info(unicam->dev, "Mediabus format:     %08x\n",
+		 node->fmtinfo->code);
+	dev_info(unicam->dev, "V4L2 format:         %08x\n",
+		 node->fmt.fmt.pix.pixelformat);
+	reg = unicam_reg_read(unicam, UNICAM_IPIPE);
+	dev_info(unicam->dev, "Unpacking/packing:   %u / %u\n",
+		 unicam_get_field(reg, UNICAM_PUM_MASK),
+		 unicam_get_field(reg, UNICAM_PPM_MASK));
+	dev_info(unicam->dev, "----Live data----\n");
+	dev_info(unicam->dev, "Programmed stride:   %4u\n",
+		 unicam_reg_read(unicam, UNICAM_IBLS));
+	dev_info(unicam->dev, "Detected resolution: %ux%u\n",
+		 unicam_reg_read(unicam, UNICAM_IHSTA),
+		 unicam_reg_read(unicam, UNICAM_IVSTA));
+	dev_info(unicam->dev, "Write pointer:       %08x\n",
+		 unicam_reg_read(unicam, UNICAM_IBWP));
+
+	return 0;
+}
+
+static int unicam_subscribe_event(struct v4l2_fh *fh,
+				  const struct v4l2_event_subscription *sub)
+{
+	switch (sub->type) {
+	case V4L2_EVENT_FRAME_SYNC:
+		return v4l2_event_subscribe(fh, sub, 2, NULL);
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct v4l2_ioctl_ops unicam_ioctl_ops = {
+	.vidioc_querycap		= unicam_querycap,
+
+	.vidioc_enum_fmt_vid_cap	= unicam_enum_fmt_vid,
+	.vidioc_g_fmt_vid_cap		= unicam_g_fmt_vid,
+	.vidioc_try_fmt_vid_cap		= unicam_try_fmt_vid,
+	.vidioc_s_fmt_vid_cap		= unicam_s_fmt_vid,
+
+	.vidioc_enum_fmt_meta_cap	= unicam_enum_fmt_meta,
+	.vidioc_g_fmt_meta_cap		= unicam_g_fmt_meta,
+	.vidioc_try_fmt_meta_cap	= unicam_try_fmt_meta,
+	.vidioc_s_fmt_meta_cap		= unicam_s_fmt_meta,
+
+	.vidioc_enum_framesizes		= unicam_enum_framesizes,
+
+	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
+	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
+	.vidioc_querybuf		= vb2_ioctl_querybuf,
+	.vidioc_qbuf			= vb2_ioctl_qbuf,
+	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
+	.vidioc_expbuf			= vb2_ioctl_expbuf,
+	.vidioc_streamon		= vb2_ioctl_streamon,
+	.vidioc_streamoff		= vb2_ioctl_streamoff,
+
+	.vidioc_log_status		= unicam_log_status,
+	.vidioc_subscribe_event		= unicam_subscribe_event,
+	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
+};
+
+/* unicam capture driver file operations */
+static const struct v4l2_file_operations unicam_fops = {
+	.owner		= THIS_MODULE,
+	.open           = v4l2_fh_open,
+	.release        = vb2_fop_release,
+	.poll		= vb2_fop_poll,
+	.unlocked_ioctl = video_ioctl2,
+	.mmap           = vb2_fop_mmap,
+};
+
+static int unicam_video_link_validate(struct media_link *link)
+{
+	struct video_device *vdev =
+		media_entity_to_video_device(link->sink->entity);
+	struct v4l2_subdev *sd =
+		media_entity_to_v4l2_subdev(link->source->entity);
+	struct unicam_node *node = video_get_drvdata(vdev);
+	const u32 pad = is_image_node(node) ? UNICAM_SD_PAD_SOURCE_IMAGE
+		      : UNICAM_SD_PAD_SOURCE_METADATA;
+	const struct v4l2_mbus_framefmt *format;
+	struct v4l2_subdev_state *state;
+	int ret = 0;
+
+	state = v4l2_subdev_lock_and_get_active_state(sd);
+
+	format = v4l2_subdev_state_get_format(state, pad, 0);
+	if (!format) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (is_image_node(node)) {
+		const struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
+
+		if (node->fmtinfo->code != format->code ||
+		    fmt->height != format->height ||
+		    fmt->width != format->width ||
+		    fmt->field != format->field) {
+			dev_dbg(node->dev->dev,
+				"image: (%u x %u) 0x%08x %s != (%u x %u) 0x%08x %s\n",
+				fmt->width, fmt->height, node->fmtinfo->code,
+				v4l2_field_names[fmt->field],
+				format->width, format->height, format->code,
+				v4l2_field_names[format->field]);
+			ret = -EPIPE;
+		};
+	} else {
+		const struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
+
+		if (node->fmtinfo->code != format->code ||
+		    fmt->height != format->height ||
+		    fmt->width != format->width) {
+			dev_dbg(node->dev->dev,
+				"meta: (%u x %u) 0x%04x != (%u x %u) 0x%04x\n",
+				fmt->width, fmt->height, node->fmtinfo->code,
+				format->width, format->height, format->code);
+			ret = -EPIPE;
+		};
+	}
+
+out:
+	v4l2_subdev_unlock_state(state);
+	return ret;
+}
+
+static const struct media_entity_operations unicam_video_media_ops = {
+	.link_validate = unicam_video_link_validate,
+};
+
+static void unicam_node_release(struct video_device *vdev)
+{
+	struct unicam_node *node = video_get_drvdata(vdev);
+
+	unicam_put(node->dev);
+}
+
+static void unicam_set_default_format(struct unicam_node *node)
+{
+	if (is_image_node(node)) {
+		struct v4l2_pix_format *fmt = &node->fmt.fmt.pix;
+
+		node->fmtinfo = &unicam_image_formats[0];
+		node->fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+		v4l2_fill_pix_format(fmt, &unicam_default_image_format);
+		fmt->pixelformat = node->fmtinfo->fourcc;
+		unicam_calc_image_size_bpl(node->dev, node->fmtinfo, fmt);
+	} else {
+		struct v4l2_meta_format *fmt = &node->fmt.fmt.meta;
+
+		node->fmtinfo = &unicam_meta_formats[0];
+		node->fmt.type = V4L2_BUF_TYPE_META_CAPTURE;
+
+		fmt->dataformat = node->fmtinfo->fourcc;
+		fmt->width = unicam_default_meta_format.width;
+		fmt->height = unicam_default_meta_format.height;
+		unicam_calc_meta_size_bpl(node->dev, node->fmtinfo, fmt);
+	}
+}
+
+static int unicam_register_node(struct unicam_device *unicam,
+				enum unicam_node_type type)
+{
+	const u32 pad_index = type == UNICAM_IMAGE_NODE
+			    ? UNICAM_SD_PAD_SOURCE_IMAGE
+			    : UNICAM_SD_PAD_SOURCE_METADATA;
+	struct unicam_node *node = &unicam->node[type];
+	struct video_device *vdev = &node->video_dev;
+	struct vb2_queue *q = &node->buffer_queue;
+	int ret;
+
+	node->dev = unicam_get(unicam);
+	node->id = type;
+
+	spin_lock_init(&node->dma_queue_lock);
+	mutex_init(&node->lock);
+
+	INIT_LIST_HEAD(&node->dma_queue);
+
+	/* Initialize the videobuf2 queue. */
+	q->type = type == UNICAM_IMAGE_NODE ? V4L2_BUF_TYPE_VIDEO_CAPTURE
+					    : V4L2_BUF_TYPE_META_CAPTURE;
+	q->io_modes = VB2_MMAP | VB2_DMABUF;
+	q->drv_priv = node;
+	q->ops = &unicam_video_qops;
+	q->mem_ops = &vb2_dma_contig_memops;
+	q->buf_struct_size = sizeof(struct unicam_buffer);
+	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	q->lock = &node->lock;
+	q->min_queued_buffers = 1;
+	q->dev = unicam->dev;
+
+	ret = vb2_queue_init(q);
+	if (ret) {
+		dev_err(unicam->dev, "vb2_queue_init() failed\n");
+		goto err_unicam_put;
+	}
+
+	/* Initialize the video device. */
+	vdev->release = unicam_node_release;
+	vdev->fops = &unicam_fops;
+	vdev->ioctl_ops = &unicam_ioctl_ops;
+	vdev->v4l2_dev = &unicam->v4l2_dev;
+	vdev->vfl_dir = VFL_DIR_RX;
+	vdev->queue = q;
+	vdev->lock = &node->lock;
+	vdev->device_caps = type == UNICAM_IMAGE_NODE
+			  ? V4L2_CAP_VIDEO_CAPTURE : V4L2_CAP_META_CAPTURE;
+	vdev->device_caps |= V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
+	vdev->entity.ops = &unicam_video_media_ops;
+
+	snprintf(vdev->name, sizeof(vdev->name), "%s-%s", UNICAM_MODULE_NAME,
+		 type == UNICAM_IMAGE_NODE ? "image" : "embedded");
+
+	video_set_drvdata(vdev, node);
+
+	if (type == UNICAM_IMAGE_NODE)
+		vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
+
+	node->pad.flags = MEDIA_PAD_FL_SINK;
+
+	ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
+	if (ret)
+		goto err_unicam_put;
+
+	node->dummy_buf.size = UNICAM_DUMMY_BUF_SIZE;
+	node->dummy_buf_cpu_addr = dma_alloc_coherent(unicam->dev,
+						      node->dummy_buf.size,
+						      &node->dummy_buf.dma_addr,
+						      GFP_KERNEL);
+	if (!node->dummy_buf_cpu_addr) {
+		dev_err(unicam->dev, "Unable to allocate dummy buffer.\n");
+		ret = -ENOMEM;
+		goto err_entity_cleanup;
+	}
+
+	unicam_set_default_format(node);
+
+	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
+	if (ret) {
+		dev_err(unicam->dev, "Unable to register video device %s\n",
+			vdev->name);
+		goto err_dma_free;
+	}
+
+	node->registered = true;
+
+	ret = media_create_pad_link(&unicam->subdev.sd.entity,
+				    pad_index,
+				    &node->video_dev.entity,
+				    0,
+				    MEDIA_LNK_FL_ENABLED |
+				    MEDIA_LNK_FL_IMMUTABLE);
+	if (ret) {
+		/*
+		 * No need for cleanup, the caller will unregister the
+		 * video device, which will drop the reference on the
+		 * device and trigger the cleanup.
+		 */
+		dev_err(unicam->dev, "Unable to create pad link for %s\n",
+			unicam->sensor.subdev->name);
+		return ret;
+	}
+
+	return 0;
+
+err_dma_free:
+	dma_free_coherent(unicam->dev, node->dummy_buf.size,
+			  node->dummy_buf_cpu_addr,
+			  node->dummy_buf.dma_addr);
+err_entity_cleanup:
+	media_entity_cleanup(&vdev->entity);
+err_unicam_put:
+	unicam_put(unicam);
+	return ret;
+}
+
+static void unicam_unregister_nodes(struct unicam_device *unicam)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(unicam->node); i++) {
+		struct unicam_node *node = &unicam->node[i];
+
+		if (node->dummy_buf_cpu_addr)
+			dma_free_coherent(unicam->dev, node->dummy_buf.size,
+					  node->dummy_buf_cpu_addr,
+					  node->dummy_buf.dma_addr);
+
+		if (node->registered) {
+			video_unregister_device(&node->video_dev);
+			node->registered = false;
+		}
+	}
+}
+
+/* -----------------------------------------------------------------------------
+ * Power management
+ */
+
+static int unicam_runtime_resume(struct device *dev)
+{
+	struct unicam_device *unicam = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_set_min_rate(unicam->vpu_clock, UNICAM_MIN_VPU_CLOCK_RATE);
+	if (ret) {
+		dev_err(unicam->dev, "failed to set up VPU clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(unicam->vpu_clock);
+	if (ret) {
+		dev_err(unicam->dev, "Failed to enable VPU clock: %d\n", ret);
+		goto err_vpu_clock;
+	}
+
+	ret = clk_set_rate(unicam->clock, 100 * 1000 * 1000);
+	if (ret) {
+		dev_err(unicam->dev, "failed to set up CSI clock\n");
+		goto err_vpu_prepare;
+	}
+
+	ret = clk_prepare_enable(unicam->clock);
+	if (ret) {
+		dev_err(unicam->dev, "Failed to enable CSI clock: %d\n", ret);
+		goto err_vpu_prepare;
+	}
+
+	return 0;
+
+err_vpu_prepare:
+	clk_disable_unprepare(unicam->vpu_clock);
+err_vpu_clock:
+	if (clk_set_min_rate(unicam->vpu_clock, 0))
+		dev_err(unicam->dev, "failed to reset the VPU clock\n");
+
+	return ret;
+}
+
+static int unicam_runtime_suspend(struct device *dev)
+{
+	struct unicam_device *unicam = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(unicam->clock);
+
+	if (clk_set_min_rate(unicam->vpu_clock, 0))
+		dev_err(unicam->dev, "failed to reset the VPU clock\n");
+
+	clk_disable_unprepare(unicam->vpu_clock);
+
+	return 0;
+}
+
+static const struct dev_pm_ops unicam_pm_ops = {
+	RUNTIME_PM_OPS(unicam_runtime_suspend, unicam_runtime_resume, NULL)
+};
+
+/* -----------------------------------------------------------------------------
+ * V4L2 async notifier
+ */
+
+static int unicam_async_bound(struct v4l2_async_notifier *notifier,
+			      struct v4l2_subdev *subdev,
+			      struct v4l2_async_connection *asc)
+{
+	struct unicam_device *unicam = notifier_to_unicam_device(notifier);
+	struct media_pad *sink = &unicam->subdev.pads[UNICAM_SD_PAD_SINK];
+	struct media_pad *source;
+	int ret;
+
+	dev_dbg(unicam->dev, "Using sensor %s for capture\n",
+		subdev->name);
+
+	ret = v4l2_create_fwnode_links_to_pad(subdev, sink, MEDIA_LNK_FL_ENABLED |
+					      MEDIA_LNK_FL_IMMUTABLE);
+	if (ret)
+		return ret;
+
+	source = media_pad_remote_pad_unique(sink);
+	if (!source) {
+		dev_err(unicam->dev, "No connected sensor pad\n");
+		return -ENOTCONN;
+	}
+
+	unicam->sensor.subdev = subdev;
+	unicam->sensor.pad = source;
+
+	return 0;
+}
+
+static int unicam_async_complete(struct v4l2_async_notifier *notifier)
+{
+	struct unicam_device *unicam = notifier_to_unicam_device(notifier);
+	int ret;
+
+	ret = unicam_register_node(unicam, UNICAM_IMAGE_NODE);
+	if (ret) {
+		dev_err(unicam->dev, "Unable to register image video device.\n");
+		goto unregister;
+	}
+
+	ret = unicam_register_node(unicam, UNICAM_METADATA_NODE);
+	if (ret) {
+		dev_err(unicam->dev, "Unable to register metadata video device.\n");
+		goto unregister;
+	}
+
+	ret = v4l2_device_register_subdev_nodes(&unicam->v4l2_dev);
+	if (ret) {
+		dev_err(unicam->dev, "Unable to register subdev nodes.\n");
+		goto unregister;
+	}
+
+	return 0;
+
+unregister:
+	unicam_unregister_nodes(unicam);
+	unicam_put(unicam);
+
+	return ret;
+}
+
+static const struct v4l2_async_notifier_operations unicam_async_ops = {
+	.bound = unicam_async_bound,
+	.complete = unicam_async_complete,
+};
+
+static int unicam_async_nf_init(struct unicam_device *unicam)
+{
+	struct v4l2_fwnode_endpoint ep = { };
+	struct fwnode_handle *ep_handle;
+	struct v4l2_async_connection *asc;
+	int ret;
+
+	ret = of_property_read_u32(unicam->dev->of_node, "brcm,num-data-lanes",
+				   &unicam->max_data_lanes);
+	if (ret < 0) {
+		dev_err(unicam->dev, "Missing %s DT property\n",
+			"brcm,num-data-lanes");
+		return -EINVAL;
+	}
+
+	/* Get and parse the local endpoint. */
+	ep_handle = fwnode_graph_get_endpoint_by_id(dev_fwnode(unicam->dev), 0, 0,
+						    FWNODE_GRAPH_ENDPOINT_NEXT);
+	if (!ep_handle) {
+		dev_err(unicam->dev, "No endpoint found\n");
+		return -ENODEV;
+	}
+
+	ret = v4l2_fwnode_endpoint_parse(ep_handle, &ep);
+	if (ret) {
+		dev_err(unicam->dev, "Failed to parse endpoint: %d\n", ret);
+		goto error;
+	}
+
+	unicam->bus_type = ep.bus_type;
+
+	switch (ep.bus_type) {
+	case V4L2_MBUS_CSI2_DPHY: {
+		unsigned int num_data_lanes = ep.bus.mipi_csi2.num_data_lanes;
+
+		if (num_data_lanes != 1 && num_data_lanes != 2 &&
+		    num_data_lanes != 4) {
+			dev_err(unicam->dev, "%u data lanes not supported\n",
+				num_data_lanes);
+			goto error;
+		}
+
+		if (num_data_lanes > unicam->max_data_lanes) {
+			dev_err(unicam->dev,
+				"Endpoint uses %u data lanes when %u are supported\n",
+				num_data_lanes, unicam->max_data_lanes);
+			goto error;
+		}
+
+		unicam->active_data_lanes = num_data_lanes;
+		unicam->bus_flags = ep.bus.mipi_csi2.flags;
+		break;
+	}
+
+	case V4L2_MBUS_CCP2:
+		unicam->max_data_lanes = 1;
+		unicam->active_data_lanes = 1;
+		unicam->bus_flags = ep.bus.mipi_csi1.strobe;
+		break;
+
+	default:
+		/* Unsupported bus type */
+		dev_err(unicam->dev, "Unsupported bus type %u\n", ep.bus_type);
+		goto error;
+	}
+
+	/* Initialize and register the async notifier. */
+	v4l2_async_nf_init(&unicam->notifier, &unicam->v4l2_dev);
+
+	asc = v4l2_async_nf_add_fwnode_remote(&unicam->notifier, ep_handle,
+					      struct v4l2_async_connection);
+	fwnode_handle_put(ep_handle);
+	ep_handle = NULL;
+
+	if (IS_ERR(asc)) {
+		ret = PTR_ERR(asc);
+		dev_err(unicam->dev, "Failed to add entry to notifier: %d\n",
+			ret);
+		goto error;
+	}
+
+	unicam->notifier.ops = &unicam_async_ops;
+
+	ret = v4l2_async_nf_register(&unicam->notifier);
+	if (ret) {
+		dev_err(unicam->dev, "Error registering device notifier: %d\n",
+			ret);
+		goto error;
+	}
+
+	return 0;
+
+error:
+	fwnode_handle_put(ep_handle);
+	return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ * Probe & remove
+ */
+
+static int unicam_media_init(struct unicam_device *unicam)
+{
+	int ret;
+
+	unicam->mdev.dev = unicam->dev;
+	strscpy(unicam->mdev.model, UNICAM_MODULE_NAME,
+		sizeof(unicam->mdev.model));
+	strscpy(unicam->mdev.serial, "", sizeof(unicam->mdev.serial));
+	unicam->mdev.hw_revision = 0;
+
+	media_device_init(&unicam->mdev);
+
+	unicam->v4l2_dev.mdev = &unicam->mdev;
+
+	ret = v4l2_device_register(unicam->dev, &unicam->v4l2_dev);
+	if (ret < 0) {
+		dev_err(unicam->dev, "Unable to register v4l2 device\n");
+		goto err_media_cleanup;
+	}
+
+	ret = media_device_register(&unicam->mdev);
+	if (ret < 0) {
+		dev_err(unicam->dev,
+			"Unable to register media-controller device\n");
+		goto err_v4l2_unregister;
+	}
+
+	return 0;
+
+err_v4l2_unregister:
+	v4l2_device_unregister(&unicam->v4l2_dev);
+err_media_cleanup:
+	media_device_cleanup(&unicam->mdev);
+	return ret;
+}
+
+static int unicam_probe(struct platform_device *pdev)
+{
+	struct unicam_device *unicam;
+	int ret;
+
+	unicam = kzalloc(sizeof(*unicam), GFP_KERNEL);
+	if (!unicam)
+		return -ENOMEM;
+
+	kref_init(&unicam->kref);
+	unicam->dev = &pdev->dev;
+	platform_set_drvdata(pdev, unicam);
+
+	unicam->base = devm_platform_ioremap_resource_byname(pdev, "unicam");
+	if (IS_ERR(unicam->base)) {
+		ret = PTR_ERR(unicam->base);
+		goto err_unicam_put;
+	}
+
+	unicam->clk_gate_base = devm_platform_ioremap_resource_byname(pdev, "cmi");
+	if (IS_ERR(unicam->clk_gate_base)) {
+		ret = PTR_ERR(unicam->clk_gate_base);
+		goto err_unicam_put;
+	}
+
+	unicam->clock = devm_clk_get(&pdev->dev, "lp");
+	if (IS_ERR(unicam->clock)) {
+		dev_err(unicam->dev, "Failed to get lp clock\n");
+		ret = PTR_ERR(unicam->clock);
+		goto err_unicam_put;
+	}
+
+	unicam->vpu_clock = devm_clk_get(&pdev->dev, "vpu");
+	if (IS_ERR(unicam->vpu_clock)) {
+		dev_err(unicam->dev, "Failed to get vpu clock\n");
+		ret = PTR_ERR(unicam->vpu_clock);
+		goto err_unicam_put;
+	}
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret <= 0) {
+		dev_err(&pdev->dev, "No IRQ resource\n");
+		ret = -EINVAL;
+		goto err_unicam_put;
+	}
+
+	ret = devm_request_irq(&pdev->dev, ret, unicam_isr, 0,
+			       "unicam_capture0", unicam);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to request interrupt\n");
+		ret = -EINVAL;
+		goto err_unicam_put;
+	}
+
+	/* Enable the block power domain. */
+	pm_runtime_enable(&pdev->dev);
+
+	ret = unicam_media_init(unicam);
+	if (ret)
+		goto err_pm_runtime;
+
+	ret = unicam_subdev_init(unicam);
+	if (ret)
+		goto err_media_unregister;
+
+	ret = unicam_async_nf_init(unicam);
+	if (ret)
+		goto err_subdev_unregister;
+
+	return 0;
+
+err_subdev_unregister:
+	unicam_subdev_cleanup(unicam);
+err_media_unregister:
+	media_device_unregister(&unicam->mdev);
+err_pm_runtime:
+	pm_runtime_disable(&pdev->dev);
+err_unicam_put:
+	unicam_put(unicam);
+
+	return ret;
+}
+
+static int unicam_remove(struct platform_device *pdev)
+{
+	struct unicam_device *unicam = platform_get_drvdata(pdev);
+
+	unicam_unregister_nodes(unicam);
+	v4l2_device_unregister(&unicam->v4l2_dev);
+	media_device_unregister(&unicam->mdev);
+	v4l2_async_nf_unregister(&unicam->notifier);
+
+	unicam_subdev_cleanup(unicam);
+
+	unicam_put(unicam);
+
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static const struct of_device_id unicam_of_match[] = {
+	{ .compatible = "brcm,bcm2835-unicam", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, unicam_of_match);
+
+static struct platform_driver unicam_driver = {
+	.probe		= unicam_probe,
+	.remove		= unicam_remove,
+	.driver = {
+		.name	= UNICAM_MODULE_NAME,
+		.pm	= pm_ptr(&unicam_pm_ops),
+		.of_match_table = of_match_ptr(unicam_of_match),
+	},
+};
+
+module_platform_driver(unicam_driver);
+
+MODULE_AUTHOR("Dave Stevenson <[e-mail]>");
+MODULE_DESCRIPTION("BCM2835 Unicam driver");
+MODULE_LICENSE("GPL");