[v4,3/5] media: mali-c55: Add Mali-C55 ISP driver

Commit Message

Dan Scally April 18, 2024, 9:08 a.m. UTC

Add a driver for Arm's Mali-C55 Image Signal Processor. The driver is
V4L2 and Media Controller compliant and creates subdevices to manage
the ISP itself, its internal test pattern generator as well as the
crop, scaler and output format functionality for each of its two
output devices.

Acked-by: Nayden Kanchev <[e-mail]>
Signed-off-by: Jacopo Mondi <[e-mail]>
Signed-off-by: Daniel Scally <[e-mail]>
---
Changes in v4:

	- Reworked mali_c55_update_bits() to internally perform the bit-shift
	- Reworked the resizer to allow cropping during streaming
	- Fixed a bug in NV12 output

Changes in v3:

	- Mostly minor fixes suggested by Sakari
	- Fixed the sequencing of vb2 buffers to be synchronised across the two
	  capture devices.

Changes in v2:

	- Clock handling
	- Fixed the warnings raised by the kernel test robot

 drivers/media/platform/Kconfig                |   1 +
 drivers/media/platform/Makefile               |   1 +
 drivers/media/platform/arm/Kconfig            |   5 +
 drivers/media/platform/arm/Makefile           |   2 +
 drivers/media/platform/arm/mali-c55/Kconfig   |  18 +
 drivers/media/platform/arm/mali-c55/Makefile  |   9 +
 .../platform/arm/mali-c55/mali-c55-capture.c  | 955 ++++++++++++++++++
 .../platform/arm/mali-c55/mali-c55-common.h   | 266 +++++
 .../platform/arm/mali-c55/mali-c55-core.c     | 748 ++++++++++++++
 .../platform/arm/mali-c55/mali-c55-isp.c      | 701 +++++++++++++
 .../arm/mali-c55/mali-c55-registers.h         | 180 ++++
 .../arm/mali-c55/mali-c55-resizer-coefs.h     | 382 +++++++
 .../platform/arm/mali-c55/mali-c55-resizer.c  | 740 ++++++++++++++
 .../platform/arm/mali-c55/mali-c55-tpg.c      | 424 ++++++++
 14 files changed, 4432 insertions(+)
 create mode 100644 drivers/media/platform/arm/Kconfig
 create mode 100644 drivers/media/platform/arm/Makefile
 create mode 100644 drivers/media/platform/arm/mali-c55/Kconfig
 create mode 100644 drivers/media/platform/arm/mali-c55/Makefile
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-capture.c
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-common.h
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-core.c
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-isp.c
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-registers.h
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
 create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-tpg.c

Comments

Sakari Ailus May 23, 2024, 8:03 a.m. UTC | #1

Hi Daniel,

Thanks for the update. A few more comments below...

On Thu, Apr 18, 2024 at 10:08:23AM +0100, Daniel Scally wrote:
> Add a driver for Arm's Mali-C55 Image Signal Processor. The driver is
> V4L2 and Media Controller compliant and creates subdevices to manage
> the ISP itself, its internal test pattern generator as well as the
> crop, scaler and output format functionality for each of its two
> output devices.
> 
> Acked-by: Nayden Kanchev <[e-mail]>
> Signed-off-by: Jacopo Mondi <[e-mail]>
> Signed-off-by: Daniel Scally <[e-mail]>
> ---
> Changes in v4:
> 
> 	- Reworked mali_c55_update_bits() to internally perform the bit-shift
> 	- Reworked the resizer to allow cropping during streaming
> 	- Fixed a bug in NV12 output
> 
> Changes in v3:
> 
> 	- Mostly minor fixes suggested by Sakari
> 	- Fixed the sequencing of vb2 buffers to be synchronised across the two
> 	  capture devices.
> 
> Changes in v2:
> 
> 	- Clock handling
> 	- Fixed the warnings raised by the kernel test robot
> 
>  drivers/media/platform/Kconfig                |   1 +
>  drivers/media/platform/Makefile               |   1 +
>  drivers/media/platform/arm/Kconfig            |   5 +
>  drivers/media/platform/arm/Makefile           |   2 +
>  drivers/media/platform/arm/mali-c55/Kconfig   |  18 +
>  drivers/media/platform/arm/mali-c55/Makefile  |   9 +
>  .../platform/arm/mali-c55/mali-c55-capture.c  | 955 ++++++++++++++++++
>  .../platform/arm/mali-c55/mali-c55-common.h   | 266 +++++
>  .../platform/arm/mali-c55/mali-c55-core.c     | 748 ++++++++++++++
>  .../platform/arm/mali-c55/mali-c55-isp.c      | 701 +++++++++++++
>  .../arm/mali-c55/mali-c55-registers.h         | 180 ++++
>  .../arm/mali-c55/mali-c55-resizer-coefs.h     | 382 +++++++
>  .../platform/arm/mali-c55/mali-c55-resizer.c  | 740 ++++++++++++++
>  .../platform/arm/mali-c55/mali-c55-tpg.c      | 424 ++++++++
>  14 files changed, 4432 insertions(+)
>  create mode 100644 drivers/media/platform/arm/Kconfig
>  create mode 100644 drivers/media/platform/arm/Makefile
>  create mode 100644 drivers/media/platform/arm/mali-c55/Kconfig
>  create mode 100644 drivers/media/platform/arm/mali-c55/Makefile
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-capture.c
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-common.h
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-core.c
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-isp.c
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-registers.h
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
>  create mode 100644 drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
> 
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index 91e54215de3a..cd92c024e039 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -65,6 +65,7 @@ config VIDEO_MUX
>  source "drivers/media/platform/allegro-dvt/Kconfig"
>  source "drivers/media/platform/amlogic/Kconfig"
>  source "drivers/media/platform/amphion/Kconfig"
> +source "drivers/media/platform/arm/Kconfig"
>  source "drivers/media/platform/aspeed/Kconfig"
>  source "drivers/media/platform/atmel/Kconfig"
>  source "drivers/media/platform/cadence/Kconfig"
> diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
> index 3296ec1ebe16..ea6624c62559 100644
> --- a/drivers/media/platform/Makefile
> +++ b/drivers/media/platform/Makefile
> @@ -8,6 +8,7 @@
>  obj-y += allegro-dvt/
>  obj-y += amlogic/
>  obj-y += amphion/
> +obj-y += arm/
>  obj-y += aspeed/
>  obj-y += atmel/
>  obj-y += cadence/
> diff --git a/drivers/media/platform/arm/Kconfig b/drivers/media/platform/arm/Kconfig
> new file mode 100644
> index 000000000000..4f0764c329c7
> --- /dev/null
> +++ b/drivers/media/platform/arm/Kconfig
> @@ -0,0 +1,5 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +
> +comment "ARM media platform drivers"
> +
> +source "drivers/media/platform/arm/mali-c55/Kconfig"
> diff --git a/drivers/media/platform/arm/Makefile b/drivers/media/platform/arm/Makefile
> new file mode 100644
> index 000000000000..8cc4918725ef
> --- /dev/null
> +++ b/drivers/media/platform/arm/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +obj-y += mali-c55/
> diff --git a/drivers/media/platform/arm/mali-c55/Kconfig b/drivers/media/platform/arm/mali-c55/Kconfig
> new file mode 100644
> index 000000000000..602085e28b01
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/Kconfig
> @@ -0,0 +1,18 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config VIDEO_MALI_C55
> +	tristate "ARM Mali-C55 Image Signal Processor driver"
> +	depends on V4L_PLATFORM_DRIVERS
> +	depends on VIDEO_DEV && OF
> +	depends on ARCH_VEXPRESS || COMPILE_TEST
> +	select MEDIA_CONTROLLER
> +	select VIDEO_V4L2_SUBDEV_API
> +	select VIDEOBUF2_DMA_CONTIG
> +	select VIDEOBUF2_VMALLOC
> +	select V4L2_FWNODE
> +	select GENERIC_PHY_MIPI_DPHY
> +	default n
> +	help
> +	  Enable this to support Arm's Mali-C55 Image Signal Processor.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called mali-c55.
> diff --git a/drivers/media/platform/arm/mali-c55/Makefile b/drivers/media/platform/arm/mali-c55/Makefile
> new file mode 100644
> index 000000000000..77dcb2fbf0f4
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/Makefile
> @@ -0,0 +1,9 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +mali-c55-y := mali-c55-capture.o \
> +	      mali-c55-core.o \
> +	      mali-c55-isp.o \
> +	      mali-c55-tpg.o \
> +	      mali-c55-resizer.o
> +
> +obj-$(CONFIG_VIDEO_MALI_C55) += mali-c55.o
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-capture.c b/drivers/media/platform/arm/mali-c55/mali-c55-capture.c
> new file mode 100644
> index 000000000000..4fcd52437b36
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-capture.c
> @@ -0,0 +1,955 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ARM Mali-C55 ISP Driver - Video capture devices
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#include <linux/cleanup.h>
> +#include <linux/minmax.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/string.h>
> +#include <linux/videodev2.h>
> +
> +#include <media/v4l2-dev.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-subdev.h>
> +#include <media/videobuf2-core.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "mali-c55-common.h"
> +#include "mali-c55-registers.h"
> +
> +/*
> + * The Mali-C55 ISP has up to two output pipes; known as full resolution and
> + * down scaled. The register space for these is laid out identically, but offset
> + * by 372 bytes.
> + */
> +#define MALI_C55_CAP_DEV_FR_REG_OFFSET		0x0
> +#define MALI_C55_CAP_DEV_DS_REG_OFFSET		0x174
> +
> +static const struct mali_c55_fmt mali_c55_fmts[] = {
> +	/*
> +	 * This table is missing some entries which need further work or
> +	 * investigation:
> +	 *
> +	 * Base mode 1 is a backwards V4L2_PIX_FMT_XRGB32 with no V4L2 equivalent
> +	 * Base mode 5 is "Generic Data"
> +	 * Base mode 8 is a backwards V4L2_PIX_FMT_XYUV32 - no V4L2 equivalent
> +	 * Base mode 9 seems to have no V4L2 equivalent
> +	 * Base mode 17, 19 and 20 describe formats which seem to have no V4L2
> +	 * equivalent
> +	 */
> +	{
> +		.fourcc = V4L2_PIX_FMT_ARGB2101010,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_RGB121212_1X36,
> +			MEDIA_BUS_FMT_RGB202020_1X60,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_A2R10G10B10,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_RGB565,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_RGB121212_1X36,
> +			MEDIA_BUS_FMT_RGB202020_1X60,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_RGB565,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_BGR24,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_RGB121212_1X36,
> +			MEDIA_BUS_FMT_RGB202020_1X60,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_RGB24,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_YUYV,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_YUV10_1X30,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_YUY2,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_UYVY,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_YUV10_1X30,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_UYVY,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_Y210,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_YUV10_1X30,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_Y210,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	/*
> +	 * This is something of a hack, the ISP thinks it's running NV12M but
> +	 * by setting uv_plane = 0 we simply discard that planes and only output
> +	 * the Y-plane.
> +	 */
> +	{
> +		.fourcc = V4L2_PIX_FMT_GREY,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_YUV10_1X30,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_NV12_21,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_NV12M,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_YUV10_1X30,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_NV12_21,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT1
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_NV21M,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_YUV10_1X30,
> +		},
> +		.is_raw = false,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_NV12_21,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT2
> +		}
> +	},
> +	/*
> +	 * RAW uncompressed formats are all packed in 16 bpp.
> +	 * TODO: Expand this list to encompass all possible RAW formats.
> +	 */
> +	{
> +		.fourcc = V4L2_PIX_FMT_SRGGB12,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_SRGGB12_1X12,
> +		},
> +		.is_raw = true,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_RAW16,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_SBGGR12,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_SBGGR12_1X12,
> +		},
> +		.is_raw = true,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_RAW16,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_SGBRG12,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_SGBRG12_1X12,
> +		},
> +		.is_raw = true,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_RAW16,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +	{
> +		.fourcc = V4L2_PIX_FMT_SGRBG12,
> +		.mbus_codes = {
> +			MEDIA_BUS_FMT_SGRBG12_1X12,
> +		},
> +		.is_raw = true,
> +		.registers = {
> +			.base_mode = MALI_C55_OUTPUT_RAW16,
> +			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
> +		}
> +	},
> +};
> +
> +static bool mali_c55_mbus_code_can_produce_fmt(const struct mali_c55_fmt *fmt,
> +					       u32 code)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(fmt->mbus_codes); i++) {
> +		if (fmt->mbus_codes[i] == code)
> +			return true;
> +	}
> +
> +	return false;
> +}
> +
> +bool mali_c55_format_is_raw(unsigned int mbus_code)
> +{
> +	for (unsigned int i = 0; i < ARRAY_SIZE(mali_c55_fmts); i++) {

You oculd declare i outside the loop. Or declare it inside the loop in
functions above and below. Up to you. But consistency would be nice.

> +		if (mali_c55_fmts[i].mbus_codes[0] == mbus_code)
> +			return mali_c55_fmts[i].is_raw;
> +	}
> +
> +	return false;
> +}
> +
> +static const struct mali_c55_fmt *mali_c55_format_from_pix(const u32 pixelformat)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55_fmts); i++) {
> +		if (mali_c55_fmts[i].fourcc == pixelformat)
> +			return &mali_c55_fmts[i];
> +	}
> +
> +	/*
> +	 * If we find no matching pixelformat, we'll just default to the first
> +	 * one for now.
> +	 */
> +
> +	return &mali_c55_fmts[0];
> +}
> +
> +static const char * const capture_device_names[] = {
> +	"mali-c55 fr",
> +	"mali-c55 ds",
> +	"mali-c55 3a stats",
> +	"mali-c55 params",
> +};
> +
> +static const char *mali_c55_cap_dev_to_name(struct mali_c55_cap_dev *cap)
> +{
> +	if (cap->reg_offset == MALI_C55_CAP_DEV_FR_REG_OFFSET)
> +		return capture_device_names[0];
> +	else if (cap->reg_offset == MALI_C55_CAP_DEV_DS_REG_OFFSET)

Useless use of else.

> +		return capture_device_names[1];
> +
> +	return "params/stat not supported yet";
> +}
> +
> +static int mali_c55_link_validate(struct media_link *link)
> +{
> +	struct video_device *vdev =
> +		media_entity_to_video_device(link->sink->entity);
> +	struct mali_c55_cap_dev *cap_dev = video_get_drvdata(vdev);
> +	struct v4l2_subdev *sd =
> +		media_entity_to_v4l2_subdev(link->source->entity);
> +	const struct v4l2_pix_format_mplane *pix_mp;
> +	const struct mali_c55_fmt *cap_fmt;
> +	struct v4l2_subdev_format sd_fmt = {
> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
> +		.pad = link->source->index,
> +	};
> +	int ret;
> +
> +	ret = v4l2_subdev_call(sd, pad, get_fmt, NULL, &sd_fmt);
> +	if (ret)
> +		return ret;
> +
> +	pix_mp = &cap_dev->mode.pix_mp;
> +	cap_fmt = cap_dev->mode.capture_fmt;
> +
> +	if (sd_fmt.format.width != pix_mp->width ||
> +	    sd_fmt.format.height != pix_mp->height) {
> +		dev_dbg(cap_dev->mali_c55->dev,
> +			"link '%s':%u -> '%s':%u not valid: %ux%u != %ux%u\n",
> +			link->source->entity->name, link->source->index,
> +			link->sink->entity->name, link->sink->index,
> +			sd_fmt.format.width, sd_fmt.format.height,
> +			pix_mp->width, pix_mp->height);
> +		return -EPIPE;
> +	}
> +
> +	if (!mali_c55_mbus_code_can_produce_fmt(cap_fmt, sd_fmt.format.code)) {
> +		dev_dbg(cap_dev->mali_c55->dev,
> +			"link '%s':%u -> '%s':%u not valid: mbus_code 0x%04x cannot produce pixel format %p4cc\n",
> +			link->source->entity->name, link->source->index,
> +			link->sink->entity->name, link->sink->index,
> +			sd_fmt.format.code, &pix_mp->pixelformat);
> +		return -EPIPE;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct media_entity_operations mali_c55_media_ops = {
> +	.link_validate = mali_c55_link_validate,
> +};
> +
> +static int mali_c55_vb2_queue_setup(struct vb2_queue *q, unsigned int *num_buffers,
> +				    unsigned int *num_planes, unsigned int sizes[],
> +				    struct device *alloc_devs[])
> +{
> +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> +	unsigned int i;
> +
> +	if (*num_planes) {
> +		if (*num_planes != cap_dev->mode.pix_mp.num_planes)
> +			return -EINVAL;
> +
> +		for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++)
> +			if (sizes[i] < cap_dev->mode.pix_mp.plane_fmt[i].sizeimage)
> +				return -EINVAL;
> +	} else {
> +		*num_planes = cap_dev->mode.pix_mp.num_planes;
> +		for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++)
> +			sizes[i] = cap_dev->mode.pix_mp.plane_fmt[i].sizeimage;
> +	}
> +
> +	return 0;
> +}
> +
> +static void mali_c55_buf_queue(struct vb2_buffer *vb)
> +{
> +	struct mali_c55_cap_dev *cap_dev = vb2_get_drv_priv(vb->vb2_queue);
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct mali_c55_buffer *buf = container_of(vbuf,
> +						   struct mali_c55_buffer, vb);
> +	unsigned int i;
> +
> +	buf->plane_done[MALI_C55_PLANE_Y] = false;
> +
> +	/*
> +	 * If we're in a single-plane format we flag the other plane as done
> +	 * already so it's dequeued appropriately later
> +	 */
> +	buf->plane_done[MALI_C55_PLANE_UV] = cap_dev->mode.pix_mp.num_planes <= 1;
> +
> +	for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++) {
> +		unsigned long size = cap_dev->mode.pix_mp.plane_fmt[i].sizeimage;
> +
> +		vb2_set_plane_payload(vb, i, size);
> +	}
> +
> +	spin_lock(&cap_dev->buffers.lock);
> +	list_add_tail(&buf->queue, &cap_dev->buffers.queue);
> +	spin_unlock(&cap_dev->buffers.lock);
> +}
> +
> +static int mali_c55_buf_init(struct vb2_buffer *vb)
> +{
> +	struct mali_c55_cap_dev *cap_dev = vb2_get_drv_priv(vb->vb2_queue);
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct mali_c55_buffer *buf = container_of(vbuf,
> +						   struct mali_c55_buffer, vb);
> +	unsigned int i;
> +
> +	for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++)
> +		buf->addrs[i] = vb2_dma_contig_plane_dma_addr(vb, i);
> +
> +	return 0;
> +}
> +
> +void mali_c55_set_next_buffer(struct mali_c55_cap_dev *cap_dev)
> +{
> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> +
> +	guard(spinlock)(&cap_dev->buffers.lock);
> +
> +	cap_dev->buffers.curr = cap_dev->buffers.next;
> +	cap_dev->buffers.next = NULL;
> +
> +	if (!list_empty(&cap_dev->buffers.queue)) {
> +		struct v4l2_pix_format_mplane *pix_mp;
> +		const struct v4l2_format_info *info;
> +		u32 *addrs;
> +
> +		pix_mp = &cap_dev->mode.pix_mp;
> +		info = v4l2_format_info(pix_mp->pixelformat);
> +
> +		mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
> +				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x01);
> +		if (cap_dev->mode.capture_fmt->registers.uv_plane)
> +			mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
> +				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x01);
> +
> +		cap_dev->buffers.next = list_first_entry(&cap_dev->buffers.queue,
> +							 struct mali_c55_buffer,
> +							 queue);
> +		list_del(&cap_dev->buffers.next->queue);
> +
> +		addrs = cap_dev->buffers.next->addrs;
> +		mali_c55_write(mali_c55,
> +			MALI_C55_REG_Y_WRITER_BANKS_BASE(cap_dev->reg_offset),
> +			addrs[MALI_C55_PLANE_Y]);
> +		mali_c55_write(mali_c55,
> +			MALI_C55_REG_UV_WRITER_BANKS_BASE(cap_dev->reg_offset),
> +			addrs[MALI_C55_PLANE_UV]);
> +		mali_c55_write(mali_c55,
> +			MALI_C55_REG_Y_WRITER_OFFSET(cap_dev->reg_offset),
> +			pix_mp->width * info->bpp[MALI_C55_PLANE_Y]);
> +		mali_c55_write(mali_c55,
> +			MALI_C55_REG_UV_WRITER_OFFSET(cap_dev->reg_offset),
> +			pix_mp->width * info->bpp[MALI_C55_PLANE_UV]
> +			/ info->hdiv);
> +	} else {
> +		/*
> +		 * If we underflow then we can tell the ISP that we don't want
> +		 * to write out the next frame.
> +		 */
> +		mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
> +				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
> +		mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
> +				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
> +	}
> +}
> +
> +static void mali_c55_handle_buffer(struct mali_c55_buffer *curr_buf,
> +				   unsigned int framecount)
> +{
> +	curr_buf->vb.vb2_buf.timestamp = ktime_get_boottime_ns();
> +	curr_buf->vb.field = V4L2_FIELD_NONE;
> +	curr_buf->vb.sequence = framecount;
> +	vb2_buffer_done(&curr_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
> +}
> +
> +/**
> + * mali_c55_set_plane_done - mark the plane as written and process the buffer if
> + *			     both planes are finished.
> + * @cap_dev:  pointer to the fr or ds pipe output
> + * @plane:    the plane to mark as completed
> + *
> + * The Mali C55 ISP has muliplanar outputs for some formats that come with two
> + * separate "buffer write completed" interrupts - we need to flag each plane's
> + * completion and check whether both planes are done - if so, complete the buf
> + * in vb2.
> + */
> +void mali_c55_set_plane_done(struct mali_c55_cap_dev *cap_dev,
> +			     enum mali_c55_planes plane)
> +{
> +	struct mali_c55_isp *isp = &cap_dev->mali_c55->isp;
> +	struct mali_c55_buffer *curr_buf;
> +
> +	guard(spinlock)(&cap_dev->buffers.lock);
> +	curr_buf = cap_dev->buffers.curr;
> +
> +	/*
> +	 * This _should_ never happen. If no buffer was available from vb2 then
> +	 * we tell the ISP not to bother writing the next frame, which means the
> +	 * interrupts that call this function should never trigger. If it does
> +	 * happen then one of our assumptions is horribly wrong - complain
> +	 * loudly and do nothing.
> +	 */
> +	if (!curr_buf) {
> +		dev_err(cap_dev->mali_c55->dev, "%s null buffer in %s()\n",
> +			mali_c55_cap_dev_to_name(cap_dev), __func__);
> +		return;
> +	}
> +
> +	/* If the other plane is also done... */
> +	if (curr_buf->plane_done[~plane & 1]) {
> +		mali_c55_handle_buffer(curr_buf, isp->frame_sequence);
> +		cap_dev->buffers.curr = NULL;
> +	} else {
> +		curr_buf->plane_done[plane] = true;
> +	}
> +}
> +
> +static void mali_c55_cap_dev_stream_disable(struct mali_c55_cap_dev *cap_dev)
> +{
> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> +
> +	mali_c55_update_bits(mali_c55,
> +			     MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
> +			     MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
> +	mali_c55_update_bits(mali_c55,
> +			     MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
> +			     MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
> +}
> +
> +static void mali_c55_cap_dev_stream_enable(struct mali_c55_cap_dev *cap_dev)
> +{
> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> +
> +	/*
> +	 * The Mali ISP can hold up to 5 buffer addresses and simply cycle
> +	 * through them, but it's not clear to me that the vb2 queue _guarantees_
> +	 * it will queue buffers to the driver in a fixed order, and ensuring
> +	 * we call vb2_buffer_done() for the right buffer seems to me to add
> +	 * pointless complexity given in multi-context mode we'd need to
> +	 * re-write those registers every frame anyway...so we tell the ISP to
> +	 * use a single register and update it for each frame.
> +	 */
> +	mali_c55_update_bits(mali_c55,
> +			MALI_C55_REG_Y_WRITER_BANKS_CONFIG(cap_dev->reg_offset),
> +			MALI_C55_REG_Y_WRITER_MAX_BANKS_MASK, 0);
> +	mali_c55_update_bits(mali_c55,
> +			MALI_C55_REG_UV_WRITER_BANKS_CONFIG(cap_dev->reg_offset),
> +			MALI_C55_REG_UV_WRITER_MAX_BANKS_MASK, 0);
> +
> +	/*
> +	 * We only queue a buffer in the streamon path if this is the first of
> +	 * the capture devices to start streaming. If the ISP is already running
> +	 * then we rely on the ISP_START interrupt to queue the first buffer for
> +	 * this capture device.
> +	 */
> +	if (mali_c55->pipe.start_count == 1)
> +		mali_c55_set_next_buffer(cap_dev);
> +}
> +
> +static void mali_c55_cap_dev_return_buffers(struct mali_c55_cap_dev *cap_dev,
> +					    enum vb2_buffer_state state)
> +{
> +	struct mali_c55_buffer *buf, *tmp;
> +
> +	guard(spinlock)(&cap_dev->buffers.lock);
> +
> +	if (cap_dev->buffers.curr) {
> +		vb2_buffer_done(&cap_dev->buffers.curr->vb.vb2_buf,
> +				state);
> +		cap_dev->buffers.curr = NULL;
> +	}
> +
> +	if (cap_dev->buffers.next) {
> +		vb2_buffer_done(&cap_dev->buffers.next->vb.vb2_buf,
> +				state);
> +		cap_dev->buffers.next = NULL;
> +	}
> +
> +	list_for_each_entry_safe(buf, tmp, &cap_dev->buffers.queue, queue) {
> +		list_del(&buf->queue);
> +		vb2_buffer_done(&buf->vb.vb2_buf, state);
> +	}
> +}
> +
> +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
> +{
> +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> +	struct mali_c55_isp *isp = &mali_c55->isp;
> +	int ret;
> +
> +	guard(mutex)(&isp->lock);
> +
> +	ret = pm_runtime_resume_and_get(mali_c55->dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = video_device_pipeline_start(&cap_dev->vdev,
> +					  &cap_dev->mali_c55->pipe);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
> +			mali_c55_cap_dev_to_name(cap_dev));
> +		goto err_pm_put;
> +	}
> +
> +	mali_c55_cap_dev_stream_enable(cap_dev);
> +	mali_c55_rzr_start_stream(rzr);
> +
> +	/*
> +	 * We only start the ISP if we're the only capture device that's
> +	 * streaming. Otherwise, it'll already be active.
> +	 */
> +	if (mali_c55->pipe.start_count == 1) {

Do you start streaming on the sensor when the first video node does?

This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
streaming on the sensor once all video nodes of the pipeline have been
started.

> +		ret = mali_c55_isp_s_stream(isp, true);
> +		if (ret)
> +			goto err_disable_cap_dev;
> +	}
> +
> +	return 0;
> +
> +err_disable_cap_dev:
> +	mali_c55_cap_dev_stream_disable(cap_dev);
> +	video_device_pipeline_stop(&cap_dev->vdev);
> +err_pm_put:
> +	pm_runtime_put(mali_c55->dev);
> +	mali_c55_cap_dev_return_buffers(cap_dev, VB2_BUF_STATE_QUEUED);
> +
> +	return ret;
> +}
> +
> +static void mali_c55_vb2_stop_streaming(struct vb2_queue *q)
> +{
> +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> +	struct mali_c55_isp *isp = &mali_c55->isp;
> +
> +	guard(mutex)(&isp->lock);
> +
> +	/*
> +	 * If one of the other capture nodes is streaming, we shouldn't
> +	 * disable the ISP here.
> +	 */
> +	if (mali_c55->pipe.start_count == 1)
> +		mali_c55_isp_s_stream(&mali_c55->isp, false);
> +
> +	mali_c55_rzr_stop_stream(rzr);
> +	mali_c55_cap_dev_stream_disable(cap_dev);
> +	mali_c55_cap_dev_return_buffers(cap_dev, VB2_BUF_STATE_ERROR);
> +	video_device_pipeline_stop(&cap_dev->vdev);
> +	pm_runtime_put(mali_c55->dev);
> +}
> +
> +static const struct vb2_ops mali_c55_vb2_ops = {
> +	.queue_setup		= &mali_c55_vb2_queue_setup,
> +	.buf_queue		= &mali_c55_buf_queue,
> +	.buf_init		= &mali_c55_buf_init,
> +	.wait_prepare		= vb2_ops_wait_prepare,
> +	.wait_finish		= vb2_ops_wait_finish,
> +	.start_streaming	= &mali_c55_vb2_start_streaming,
> +	.stop_streaming		= &mali_c55_vb2_stop_streaming,
> +};
> +
> +static const struct v4l2_file_operations mali_c55_v4l2_fops = {
> +	.owner = THIS_MODULE,
> +	.unlocked_ioctl = video_ioctl2,
> +	.open = v4l2_fh_open,
> +	.release = vb2_fop_release,
> +	.poll = vb2_fop_poll,
> +	.mmap = vb2_fop_mmap,
> +};
> +
> +static void mali_c55_try_fmt(struct v4l2_pix_format_mplane *pix_mp)
> +{
> +	const struct mali_c55_fmt *capture_format;
> +	const struct v4l2_format_info *info;
> +	struct v4l2_plane_pix_format *plane;
> +	unsigned int i;
> +
> +	capture_format = mali_c55_format_from_pix(pix_mp->pixelformat);
> +	pix_mp->pixelformat = capture_format->fourcc;
> +
> +	pix_mp->width = clamp(pix_mp->width, MALI_C55_MIN_WIDTH,
> +			      MALI_C55_MAX_WIDTH);
> +	pix_mp->height = clamp(pix_mp->height, MALI_C55_MIN_HEIGHT,
> +			       MALI_C55_MAX_HEIGHT);
> +
> +	pix_mp->field = V4L2_FIELD_NONE;
> +	pix_mp->colorspace = V4L2_COLORSPACE_DEFAULT;
> +	pix_mp->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
> +	pix_mp->quantization = V4L2_QUANTIZATION_DEFAULT;
> +
> +	info = v4l2_format_info(pix_mp->pixelformat);
> +	pix_mp->num_planes = info->mem_planes;
> +	memset(pix_mp->plane_fmt, 0, sizeof(pix_mp->plane_fmt));
> +
> +	pix_mp->plane_fmt[0].bytesperline = info->bpp[0] * pix_mp->width;
> +	pix_mp->plane_fmt[0].sizeimage = info->bpp[0] * pix_mp->width
> +				       * pix_mp->height;
> +
> +	for (i = 1; i < info->comp_planes; i++) {
> +		plane = &pix_mp->plane_fmt[i];
> +
> +		plane->bytesperline = DIV_ROUND_UP(info->bpp[i] * pix_mp->width,
> +						   info->hdiv);
> +		plane->sizeimage = DIV_ROUND_UP(
> +					plane->bytesperline * pix_mp->height,
> +					info->vdiv);
> +	}
> +
> +	if (info->mem_planes == 1) {
> +		for (i = 1; i < info->comp_planes; i++) {
> +			plane = &pix_mp->plane_fmt[i];
> +			pix_mp->plane_fmt[0].sizeimage += plane->sizeimage;
> +		}
> +	}
> +}
> +
> +static int mali_c55_try_fmt_vid_cap_mplane(struct file *file, void *fh,
> +					   struct v4l2_format *f)
> +{
> +	mali_c55_try_fmt(&f->fmt.pix_mp);
> +
> +	return 0;
> +}
> +
> +static void mali_c55_set_format(struct mali_c55_cap_dev *cap_dev,
> +				struct v4l2_pix_format_mplane *pix_mp)
> +{
> +	const struct mali_c55_fmt *capture_format;
> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> +	const struct v4l2_format_info *info;
> +
> +	mali_c55_try_fmt(pix_mp);
> +	capture_format = mali_c55_format_from_pix(pix_mp->pixelformat);
> +	info = v4l2_format_info(pix_mp->pixelformat);
> +	if (WARN_ON(!info))
> +		return;
> +
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
> +		       capture_format->registers.base_mode);
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_ACTIVE_OUT_Y_SIZE(cap_dev->reg_offset),
> +		       MALI_C55_REG_ACTIVE_OUT_SIZE_W(pix_mp->width) |
> +		       MALI_C55_REG_ACTIVE_OUT_SIZE_H(pix_mp->height));
> +
> +	if (info->mem_planes > 1) {
> +		mali_c55_write(mali_c55,
> +			       MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
> +			       capture_format->registers.base_mode);
> +		mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
> +				MALI_C55_WRITER_SUBMODE_MASK,
> +				capture_format->registers.uv_plane);
> +
> +		mali_c55_write(mali_c55,
> +			MALI_C55_REG_ACTIVE_OUT_UV_SIZE(cap_dev->reg_offset),
> +			MALI_C55_REG_ACTIVE_OUT_SIZE_W(pix_mp->width) |
> +			MALI_C55_REG_ACTIVE_OUT_SIZE_H(pix_mp->height));
> +	}
> +
> +	if (info->pixel_enc == V4L2_PIXEL_ENC_YUV) {
> +		/*
> +		 * TODO: Figure out the colour matrix coefficients and calculate
> +		 * and write them here.
> +		 */
> +
> +		mali_c55_write(mali_c55,
> +			       MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
> +			       MALI_C55_CS_CONV_MATRIX_MASK);
> +
> +		if (info->hdiv > 1)
> +			mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
> +				MALI_C55_CS_CONV_HORZ_DOWNSAMPLE_MASK, 0x01);
> +		if (info->vdiv > 1)
> +			mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
> +				MALI_C55_CS_CONV_VERT_DOWNSAMPLE_MASK, 0x01);
> +		if (info->hdiv > 1 || info->vdiv > 1)
> +			mali_c55_update_bits(mali_c55,
> +				MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
> +				MALI_C55_CS_CONV_FILTER_MASK, 0x01);
> +	}
> +
> +	cap_dev->mode.pix_mp = *pix_mp;
> +	cap_dev->mode.capture_fmt = capture_format;
> +}
> +
> +static int mali_c55_s_fmt_vid_cap_mplane(struct file *file, void *fh,
> +					 struct v4l2_format *f)
> +{
> +	struct mali_c55_cap_dev *cap_dev = video_drvdata(file);
> +
> +	if (vb2_is_busy(&cap_dev->queue))
> +		return -EBUSY;
> +
> +	mali_c55_set_format(cap_dev, &f->fmt.pix_mp);
> +
> +	return 0;
> +}
> +
> +static int mali_c55_g_fmt_vid_cap_mplane(struct file *file, void *fh,
> +					 struct v4l2_format *f)
> +{
> +	struct mali_c55_cap_dev *cap_dev = video_drvdata(file);
> +
> +	f->fmt.pix_mp = cap_dev->mode.pix_mp;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_enum_fmt_vid_cap_mplane(struct file *file, void *fh,
> +					    struct v4l2_fmtdesc *f)
> +{
> +	struct mali_c55_cap_dev *cap_dev = video_drvdata(file);
> +	unsigned int j = 0;
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55_fmts); i++) {
> +		if (f->mbus_code &&
> +		    !mali_c55_mbus_code_can_produce_fmt(&mali_c55_fmts[i],
> +						       f->mbus_code))
> +			continue;
> +
> +		/* Downscale pipe can't output RAW formats */
> +		if (mali_c55_fmts[i].is_raw &&
> +		    cap_dev->reg_offset == MALI_C55_CAP_DEV_DS_REG_OFFSET)
> +			continue;
> +
> +		if (j++ == f->index) {
> +			f->pixelformat = mali_c55_fmts[i].fourcc;
> +			return 0;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int mali_c55_querycap(struct file *file, void *fh,
> +			     struct v4l2_capability *cap)
> +{
> +	strscpy(cap->driver, MALI_C55_DRIVER_NAME, sizeof(cap->driver));
> +	strscpy(cap->card, "ARM Mali-C55 ISP", sizeof(cap->card));
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_ioctl_ops mali_c55_v4l2_ioctl_ops = {
> +	.vidioc_reqbufs = vb2_ioctl_reqbufs,
> +	.vidioc_querybuf = vb2_ioctl_querybuf,
> +	.vidioc_create_bufs = vb2_ioctl_create_bufs,
> +	.vidioc_qbuf = vb2_ioctl_qbuf,
> +	.vidioc_expbuf = vb2_ioctl_expbuf,
> +	.vidioc_dqbuf = vb2_ioctl_dqbuf,
> +	.vidioc_prepare_buf = vb2_ioctl_prepare_buf,
> +	.vidioc_streamon = vb2_ioctl_streamon,
> +	.vidioc_streamoff = vb2_ioctl_streamoff,
> +	.vidioc_try_fmt_vid_cap_mplane = mali_c55_try_fmt_vid_cap_mplane,
> +	.vidioc_s_fmt_vid_cap_mplane = mali_c55_s_fmt_vid_cap_mplane,
> +	.vidioc_g_fmt_vid_cap_mplane = mali_c55_g_fmt_vid_cap_mplane,
> +	.vidioc_enum_fmt_vid_cap = mali_c55_enum_fmt_vid_cap_mplane,
> +	.vidioc_querycap = mali_c55_querycap,
> +	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
> +	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
> +};
> +
> +int mali_c55_register_capture_devs(struct mali_c55 *mali_c55)
> +{
> +	struct v4l2_pix_format_mplane pix_mp;
> +	struct mali_c55_cap_dev *cap_dev;
> +	struct video_device *vdev;
> +	struct vb2_queue *vb2q;
> +	unsigned int i;
> +	int ret;
> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55->cap_devs); i++) {
> +		cap_dev = &mali_c55->cap_devs[i];
> +		vdev = &cap_dev->vdev;
> +		vb2q = &cap_dev->queue;
> +
> +		/*
> +		 * The downscale output pipe is an optional block within the ISP
> +		 * so we need to check whether it's actually been fitted or not.
> +		 */
> +
> +		if (i == MALI_C55_CAP_DEV_DS &&
> +		    !(mali_c55->capabilities & MALI_C55_GPS_DS_PIPE_FITTED))
> +			continue;
> +
> +		cap_dev->mali_c55 = mali_c55;
> +		mutex_init(&cap_dev->lock);
> +		INIT_LIST_HEAD(&cap_dev->buffers.queue);
> +
> +		switch (i) {
> +		case MALI_C55_CAP_DEV_FR:
> +			cap_dev->rzr = &mali_c55->resizers[MALI_C55_RZR_FR];
> +			cap_dev->reg_offset = MALI_C55_CAP_DEV_FR_REG_OFFSET;
> +			break;
> +		case MALI_C55_CAP_DEV_DS:
> +			cap_dev->rzr = &mali_c55->resizers[MALI_C55_RZR_DS];
> +			cap_dev->reg_offset = MALI_C55_CAP_DEV_DS_REG_OFFSET;
> +			break;
> +		default:
> +			mutex_destroy(&cap_dev->lock);
> +			ret = -EINVAL;
> +			goto err_destroy_mutex;
> +		}
> +
> +		cap_dev->pad.flags = MEDIA_PAD_FL_SINK;
> +		ret = media_entity_pads_init(&cap_dev->vdev.entity, 1, &cap_dev->pad);
> +		if (ret) {
> +			mutex_destroy(&cap_dev->lock);
> +			goto err_destroy_mutex;
> +		}
> +
> +		vb2q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
> +		vb2q->io_modes = VB2_MMAP | VB2_DMABUF;
> +		vb2q->drv_priv = cap_dev;
> +		vb2q->mem_ops = &vb2_dma_contig_memops;
> +		vb2q->ops = &mali_c55_vb2_ops;
> +		vb2q->buf_struct_size = sizeof(struct mali_c55_buffer);
> +		vb2q->min_queued_buffers = 1;
> +		vb2q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> +		vb2q->lock = &cap_dev->lock;
> +		vb2q->dev = mali_c55->dev;
> +
> +		ret = vb2_queue_init(vb2q);
> +		if (ret) {
> +			dev_err(mali_c55->dev, "%s vb2 queue init failed\n",
> +				mali_c55_cap_dev_to_name(cap_dev));
> +			goto err_cleanup_media_entity;
> +		}
> +
> +		strscpy(cap_dev->vdev.name, capture_device_names[i],
> +			sizeof(cap_dev->vdev.name));
> +		vdev->release = video_device_release_empty;
> +		vdev->fops = &mali_c55_v4l2_fops;
> +		vdev->ioctl_ops = &mali_c55_v4l2_ioctl_ops;
> +		vdev->lock = &cap_dev->lock;
> +		vdev->v4l2_dev = &mali_c55->v4l2_dev;
> +		vdev->queue = &cap_dev->queue;
> +		vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE_MPLANE |
> +				    V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
> +		vdev->entity.ops = &mali_c55_media_ops;
> +		video_set_drvdata(vdev, cap_dev);
> +
> +		memset(&pix_mp, 0, sizeof(pix_mp));
> +		pix_mp.pixelformat = V4L2_PIX_FMT_RGB565;
> +		pix_mp.width = MALI_C55_DEFAULT_WIDTH;
> +		pix_mp.height = MALI_C55_DEFAULT_HEIGHT;
> +		mali_c55_set_format(cap_dev, &pix_mp);
> +
> +		ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
> +		if (ret) {
> +			dev_err(mali_c55->dev,
> +				"%s failed to register video device\n",
> +				mali_c55_cap_dev_to_name(cap_dev));
> +			goto err_release_vb2q;
> +		}
> +	}
> +
> +	return 0;
> +
> +err_release_vb2q:
> +	vb2_queue_release(vb2q);
> +err_cleanup_media_entity:
> +	media_entity_cleanup(&cap_dev->vdev.entity);
> +err_destroy_mutex:
> +	mutex_destroy(&cap_dev->lock);
> +	mali_c55_unregister_capture_devs(mali_c55);
> +
> +	return ret;
> +}
> +
> +void mali_c55_unregister_capture_devs(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_cap_dev *cap_dev;
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55->cap_devs); i++) {
> +		cap_dev = &mali_c55->cap_devs[i];
> +
> +		if (!video_is_registered(&cap_dev->vdev))
> +			continue;
> +
> +		vb2_video_unregister_device(&cap_dev->vdev);
> +		media_entity_cleanup(&cap_dev->vdev.entity);
> +		mutex_destroy(&cap_dev->lock);
> +	}
> +}
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-common.h b/drivers/media/platform/arm/mali-c55/mali-c55-common.h
> new file mode 100644
> index 000000000000..3c4e3f13961b
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-common.h
> @@ -0,0 +1,266 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * ARM Mali-C55 ISP Driver - Common definitions
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#ifndef _MALI_C55_COMMON_H
> +#define _MALI_C55_COMMON_H
> +
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/list.h>
> +#include <linux/mutex.h>
> +#include <linux/scatterlist.h>
> +#include <linux/videodev2.h>
> +
> +#include <media/media-device.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-dev.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-subdev.h>
> +#include <media/videobuf2-core.h>
> +#include <media/videobuf2-v4l2.h>
> +
> +#define MALI_C55_DRIVER_NAME		"mali-c55"
> +
> +/* min and max values for the image sizes */
> +#define MALI_C55_MIN_WIDTH		640U
> +#define MALI_C55_MIN_HEIGHT		480U
> +#define MALI_C55_MAX_WIDTH		8192U
> +#define MALI_C55_MAX_HEIGHT		8192U
> +#define MALI_C55_DEFAULT_WIDTH		1920U
> +#define MALI_C55_DEFAULT_HEIGHT		1080U
> +
> +#define MALI_C55_DEFAULT_MEDIA_BUS_FMT	MEDIA_BUS_FMT_RGB121212_1X36
> +
> +struct mali_c55;
> +struct mali_c55_cap_dev;
> +struct platform_device;
> +
> +static const char * const mali_c55_clk_names[] = {
> +	"aclk",
> +	"hclk",
> +};
> +
> +enum mali_c55_interrupts {
> +	MALI_C55_IRQ_ISP_START,
> +	MALI_C55_IRQ_ISP_DONE,
> +	MALI_C55_IRQ_MCM_ERROR,
> +	MALI_C55_IRQ_BROKEN_FRAME_ERROR,
> +	MALI_C55_IRQ_MET_AF_DONE,
> +	MALI_C55_IRQ_MET_AEXP_DONE,
> +	MALI_C55_IRQ_MET_AWB_DONE,
> +	MALI_C55_IRQ_AEXP_1024_DONE,
> +	MALI_C55_IRQ_IRIDIX_MET_DONE,
> +	MALI_C55_IRQ_LUT_INIT_DONE,
> +	MALI_C55_IRQ_FR_Y_DONE,
> +	MALI_C55_IRQ_FR_UV_DONE,
> +	MALI_C55_IRQ_DS_Y_DONE,
> +	MALI_C55_IRQ_DS_UV_DONE,
> +	MALI_C55_IRQ_LINEARIZATION_DONE,
> +	MALI_C55_IRQ_RAW_FRONTEND_DONE,
> +	MALI_C55_IRQ_NOISE_REDUCTION_DONE,
> +	MALI_C55_IRQ_IRIDIX_DONE,
> +	MALI_C55_IRQ_BAYER2RGB_DONE,
> +	MALI_C55_IRQ_WATCHDOG_TIMER,
> +	MALI_C55_IRQ_FRAME_COLLISION,
> +	MALI_C55_IRQ_UNUSED,
> +	MALI_C55_IRQ_DMA_ERROR,
> +	MALI_C55_IRQ_INPUT_STOPPED,
> +	MALI_C55_IRQ_MET_AWB_TARGET1_HIT,
> +	MALI_C55_IRQ_MET_AWB_TARGET2_HIT,
> +	MALI_C55_NUM_IRQ_BITS
> +};
> +
> +enum mali_c55_isp_pads {
> +	MALI_C55_ISP_PAD_SINK_VIDEO,
> +	MALI_C55_ISP_PAD_SOURCE,
> +	MALI_C55_ISP_PAD_SOURCE_BYPASS,
> +	MALI_C55_ISP_NUM_PADS,
> +};
> +
> +struct mali_c55_tpg {
> +	struct mali_c55 *mali_c55;
> +	struct v4l2_subdev sd;
> +	struct media_pad pad;
> +	struct mutex lock;
> +	struct mali_c55_tpg_ctrls {
> +		struct v4l2_ctrl_handler handler;
> +		struct v4l2_ctrl *test_pattern;
> +		struct v4l2_ctrl *hblank;
> +		struct v4l2_ctrl *vblank;
> +	} ctrls;
> +};
> +
> +struct mali_c55_isp {
> +	struct mali_c55 *mali_c55;
> +	struct v4l2_subdev sd;
> +	struct media_pad pads[MALI_C55_ISP_NUM_PADS];
> +	struct v4l2_subdev *source;
> +	struct v4l2_async_notifier notifier;
> +	struct mutex lock;
> +	unsigned int frame_sequence;
> +};
> +
> +enum mali_c55_resizer_ids {
> +	MALI_C55_RZR_FR,
> +	MALI_C55_RZR_DS,
> +	MALI_C55_NUM_RZRS,
> +};
> +
> +enum mali_c55_rzr_pads {
> +	MALI_C55_RZR_SINK_PAD,
> +	MALI_C55_RZR_SOURCE_PAD,
> +	MALI_C55_RZR_SINK_BYPASS_PAD,
> +	MALI_C55_RZR_NUM_PADS
> +};
> +
> +struct mali_c55_resizer {
> +	struct mali_c55 *mali_c55;
> +	struct mali_c55_cap_dev *cap_dev;
> +	enum mali_c55_resizer_ids id;
> +	struct v4l2_subdev sd;
> +	struct media_pad pads[MALI_C55_RZR_NUM_PADS];
> +	unsigned int num_routes;
> +	bool streaming;
> +};
> +
> +enum mali_c55_cap_devs {
> +	MALI_C55_CAP_DEV_FR,
> +	MALI_C55_CAP_DEV_DS,
> +	MALI_C55_NUM_CAP_DEVS
> +};
> +
> +struct mali_c55_fmt {
> +	u32 fourcc;
> +	unsigned int mbus_codes[2];
> +	bool is_raw;
> +	struct mali_c55_fmt_registers {
> +		unsigned int base_mode;
> +		unsigned int uv_plane;
> +	} registers;
> +};
> +
> +enum mali_c55_isp_bayer_order {
> +	MALI_C55_BAYER_ORDER_RGGB,
> +	MALI_C55_BAYER_ORDER_GRBG,
> +	MALI_C55_BAYER_ORDER_GBRG,
> +	MALI_C55_BAYER_ORDER_BGGR
> +};
> +
> +struct mali_c55_isp_fmt {
> +	u32 code;
> +	u8 bitwidth;
> +	enum v4l2_pixel_encoding encoding;
> +	enum mali_c55_isp_bayer_order order;
> +};
> +
> +enum mali_c55_planes {
> +	MALI_C55_PLANE_Y,
> +	MALI_C55_PLANE_UV,
> +	MALI_C55_NUM_PLANES
> +};
> +
> +struct mali_c55_buffer {
> +	struct vb2_v4l2_buffer vb;
> +	bool plane_done[MALI_C55_NUM_PLANES];
> +	struct list_head queue;
> +	u32 addrs[MALI_C55_NUM_PLANES];
> +};
> +
> +struct mali_c55_cap_dev {
> +	struct mali_c55 *mali_c55;
> +	struct mali_c55_resizer *rzr;
> +	struct video_device vdev;
> +	struct media_pad pad;
> +	struct vb2_queue queue;
> +	struct mutex lock;
> +	unsigned int reg_offset;
> +
> +	struct mali_c55_mode {
> +		const struct mali_c55_fmt *capture_fmt;
> +		struct v4l2_pix_format_mplane pix_mp;
> +	} mode;
> +
> +	struct {
> +		spinlock_t lock;
> +		struct list_head queue;
> +		struct mali_c55_buffer *curr;
> +		struct mali_c55_buffer *next;
> +	} buffers;
> +
> +	bool streaming;
> +};
> +
> +enum mali_c55_config_spaces {
> +	MALI_C55_CONFIG_PING,
> +	MALI_C55_CONFIG_PONG,
> +	MALI_C55_NUM_CONFIG_SPACES
> +};
> +
> +struct mali_c55_ctx {
> +	struct mali_c55 *mali_c55;
> +	void *registers;
> +	phys_addr_t base;
> +	spinlock_t lock;
> +	struct list_head list;
> +};
> +
> +struct mali_c55 {
> +	struct device *dev;
> +	struct resource *res;
> +	void __iomem *base;
> +	struct dma_chan *channel;
> +	struct clk_bulk_data clks[ARRAY_SIZE(mali_c55_clk_names)];
> +
> +	u16 capabilities;
> +	struct media_device media_dev;
> +	struct v4l2_device v4l2_dev;
> +	struct media_pipeline pipe;
> +
> +	struct mali_c55_tpg tpg;
> +	struct mali_c55_isp isp;
> +	struct mali_c55_resizer resizers[MALI_C55_NUM_RZRS];
> +	struct mali_c55_cap_dev cap_devs[MALI_C55_NUM_CAP_DEVS];
> +
> +	struct list_head contexts;
> +	enum mali_c55_config_spaces next_config;
> +};
> +
> +void mali_c55_write(struct mali_c55 *mali_c55, unsigned int addr, u32 val);
> +u32 mali_c55_read(struct mali_c55 *mali_c55, unsigned int addr,
> +		  bool force_hardware);
> +void mali_c55_update_bits(struct mali_c55 *mali_c55, unsigned int addr,
> +			  u32 mask, u32 val);
> +int mali_c55_config_write(struct mali_c55_ctx *ctx,
> +			  enum mali_c55_config_spaces cfg_space);
> +
> +int mali_c55_register_isp(struct mali_c55 *mali_c55);
> +int mali_c55_register_tpg(struct mali_c55 *mali_c55);
> +void mali_c55_unregister_tpg(struct mali_c55 *mali_c55);
> +void mali_c55_unregister_isp(struct mali_c55 *mali_c55);
> +int mali_c55_register_resizers(struct mali_c55 *mali_c55);
> +void mali_c55_unregister_resizers(struct mali_c55 *mali_c55);
> +int mali_c55_register_capture_devs(struct mali_c55 *mali_c55);
> +void mali_c55_unregister_capture_devs(struct mali_c55 *mali_c55);
> +struct mali_c55_ctx *mali_c55_get_active_context(struct mali_c55 *mali_c55);
> +void mali_c55_set_plane_done(struct mali_c55_cap_dev *cap_dev,
> +			     enum mali_c55_planes plane);
> +void mali_c55_set_next_buffer(struct mali_c55_cap_dev *cap_dev);
> +void mali_c55_isp_queue_event_sof(struct mali_c55 *mali_c55);
> +
> +bool mali_c55_format_is_raw(unsigned int mbus_code);
> +void mali_c55_rzr_start_stream(struct mali_c55_resizer *rzr);
> +void mali_c55_rzr_stop_stream(struct mali_c55_resizer *rzr);
> +int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable);
> +
> +const struct mali_c55_isp_fmt *
> +mali_c55_isp_fmt_next(const struct mali_c55_isp_fmt *fmt);
> +bool mali_c55_isp_is_format_supported(unsigned int mbus_code);
> +#define for_each_mali_isp_fmt(fmt)\
> +	for ((fmt) = NULL; ((fmt) = mali_c55_isp_fmt_next((fmt)));)

I think this would look nicer written as

	for (fmt = mali_c55_isp_fmt_next(NULL); ;
	     fmt = mali_c55_isp_fmt_next(fmt))

Up to you.

> +
> +#endif /* _MALI_C55_COMMON_H */
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-core.c b/drivers/media/platform/arm/mali-c55/mali-c55-core.c
> new file mode 100644
> index 000000000000..b30274556e75
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-core.c
> @@ -0,0 +1,748 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ARM Mali-C55 ISP Driver - Core driver code
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/cleanup.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dmaengine.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/iopoll.h>
> +#include <linux/ioport.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/of.h>
> +#include <linux/of_reserved_mem.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/scatterlist.h>
> +#include <linux/string.h>
> +
> +#include <media/media-entity.h>
> +#include <media/v4l2-device.h>
> +#include <media/videobuf2-dma-contig.h>
> +
> +#include "mali-c55-common.h"
> +#include "mali-c55-registers.h"
> +
> +static const char * const mali_c55_interrupt_names[] = {
> +	[MALI_C55_IRQ_ISP_START] = "ISP start",
> +	[MALI_C55_IRQ_ISP_DONE] = "ISP done",
> +	[MALI_C55_IRQ_MCM_ERROR] = "Multi-context management error",
> +	[MALI_C55_IRQ_BROKEN_FRAME_ERROR] = "Broken frame error",
> +	[MALI_C55_IRQ_MET_AF_DONE] = "AF metering done",
> +	[MALI_C55_IRQ_MET_AEXP_DONE] = "AEXP metering done",
> +	[MALI_C55_IRQ_MET_AWB_DONE] = "AWB metering done",
> +	[MALI_C55_IRQ_AEXP_1024_DONE] = "AEXP 1024-bit histogram done",
> +	[MALI_C55_IRQ_IRIDIX_MET_DONE] = "Iridix metering done",
> +	[MALI_C55_IRQ_LUT_INIT_DONE] = "LUT memory init done",
> +	[MALI_C55_IRQ_FR_Y_DONE] = "Full resolution Y plane DMA done",
> +	[MALI_C55_IRQ_FR_UV_DONE] = "Full resolution U/V plane DMA done",
> +	[MALI_C55_IRQ_DS_Y_DONE] = "Downscale Y plane DMA done",
> +	[MALI_C55_IRQ_DS_UV_DONE] = "Downscale U/V plane DMA done",
> +	[MALI_C55_IRQ_LINEARIZATION_DONE] = "Linearisation done",
> +	[MALI_C55_IRQ_RAW_FRONTEND_DONE] = "Raw frontend processing done",
> +	[MALI_C55_IRQ_NOISE_REDUCTION_DONE] = "Noise reduction done",
> +	[MALI_C55_IRQ_IRIDIX_DONE] = "Iridix done",
> +	[MALI_C55_IRQ_BAYER2RGB_DONE] = "Bayer to RGB conversion done",
> +	[MALI_C55_IRQ_WATCHDOG_TIMER] = "Watchdog timer timed out",
> +	[MALI_C55_IRQ_FRAME_COLLISION] = "Frame collision error",
> +	[MALI_C55_IRQ_UNUSED] = "IRQ bit unused",
> +	[MALI_C55_IRQ_DMA_ERROR] = "DMA error",
> +	[MALI_C55_IRQ_INPUT_STOPPED] = "Input port safely stopped",
> +	[MALI_C55_IRQ_MET_AWB_TARGET1_HIT] = "AWB metering target 1 address hit",
> +	[MALI_C55_IRQ_MET_AWB_TARGET2_HIT] = "AWB metering target 2 address hit"
> +};
> +
> +static unsigned int config_space_addrs[] = {
> +	[MALI_C55_CONFIG_PING] = 0x0AB6C,
> +	[MALI_C55_CONFIG_PONG] = 0x22B2C,
> +};
> +
> +/* System IO
> + *
> + * The Mali-C55 ISP has up to two configuration register spaces (called 'ping'
> + * and 'pong'), with the  expectation that the 'active' space will be left
> + * untouched whilst a frame is being processed and the 'inactive' space
> + * configured ready to be passed during the blanking period before the next
> + * frame processing starts. These spaces should ideally be set via DMA transfer
> + * from a buffer rather than through individual register set operations. There
> + * is also a shared global register space which should be set normally. Of
> + * course, the ISP might be included in a system which lacks a suitable DMA
> + * engine, and the second configuration space might not be fitted at all, which
> + * means we need to support four scenarios:
> + *
> + * 1. Multi config space, with DMA engine.
> + * 2. Multi config space, no DMA engine.
> + * 3. Single config space, with DMA engine.
> + * 4. Single config space, no DMA engine.
> + *
> + * The first case is very easy, but the rest present annoying problems. The best
> + * way to solve them seems to be simply to replicate the concept of DMAing over
> + * the configuration buffer even if there's no DMA engine on the board, for
> + * which we rely on memcpy. To facilitate this any read/write call that is made
> + * to an address within those config spaces should infact be directed to a
> + * buffer that was allocated to hold them rather than the IO memory itself. The
> + * actual copy of that buffer to IO mem will happen on interrupt.
> + */
> +
> +void mali_c55_write(struct mali_c55 *mali_c55, unsigned int addr, u32 val)
> +{
> +	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
> +
> +	if (addr >= MALI_C55_REG_CONFIG_SPACES_OFFSET) {
> +		spin_lock(&ctx->lock);
> +		addr = (addr - MALI_C55_REG_CONFIG_SPACES_OFFSET) / 4;
> +		((u32 *)ctx->registers)[addr] = val;
> +		spin_unlock(&ctx->lock);
> +
> +		return;
> +	}
> +
> +	writel(val, mali_c55->base + addr);
> +}
> +
> +u32 mali_c55_read(struct mali_c55 *mali_c55, unsigned int addr,
> +		  bool force_hardware)
> +{
> +	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
> +	u32 val;
> +
> +	if (addr >= MALI_C55_REG_CONFIG_SPACES_OFFSET && !force_hardware) {
> +		spin_lock(&ctx->lock);
> +		addr = (addr - MALI_C55_REG_CONFIG_SPACES_OFFSET) / 4;
> +		val = ((u32 *)ctx->registers)[addr];
> +		spin_unlock(&ctx->lock);
> +
> +		return val;
> +	}
> +
> +	return readl(mali_c55->base + addr);
> +}
> +
> +void mali_c55_update_bits(struct mali_c55 *mali_c55, unsigned int addr,
> +			  u32 mask, u32 val)
> +{
> +	u32 orig, tmp;
> +
> +	orig = mali_c55_read(mali_c55, addr, false);
> +
> +	tmp = orig & ~mask;
> +	tmp |= (val << (ffs(mask) - 1)) & mask;
> +
> +	if (tmp != orig)
> +		mali_c55_write(mali_c55, addr, tmp);
> +}
> +
> +static int mali_c55_dma_xfer(struct mali_c55_ctx *ctx, dma_addr_t src,
> +			     dma_addr_t dst, enum dma_data_direction dir)
> +{
> +	struct mali_c55 *mali_c55 = ctx->mali_c55;
> +	struct dma_async_tx_descriptor *tx;
> +	enum dma_status status;
> +	dma_cookie_t cookie;
> +
> +	tx = dmaengine_prep_dma_memcpy(mali_c55->channel, dst, src,
> +				       MALI_C55_CONFIG_SPACE_SIZE, 0);
> +	if (!tx) {
> +		dev_err(mali_c55->dev, "failed to prep DMA memcpy\n");
> +		return -EIO;
> +	}
> +
> +	cookie = dmaengine_submit(tx);
> +	if (dma_submit_error(cookie)) {
> +		dev_err(mali_c55->dev, "error submitting dma transfer\n");
> +		return -EIO;
> +	}
> +
> +	status = dma_sync_wait(mali_c55->channel, cookie);
> +	if (status != DMA_COMPLETE) {
> +		dev_err(mali_c55->dev, "dma transfer failed\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static int mali_c55_dma_read(struct mali_c55_ctx *ctx,
> +			     enum mali_c55_config_spaces cfg_space)
> +{
> +	struct mali_c55 *mali_c55 = ctx->mali_c55;
> +	struct device *dma_dev = mali_c55->channel->device->dev;
> +	dma_addr_t src = ctx->base + config_space_addrs[cfg_space];
> +	dma_addr_t dst;
> +	int ret;
> +
> +	guard(spinlock)(&ctx->lock);
> +
> +	dst = dma_map_single(dma_dev, ctx->registers,
> +			     MALI_C55_CONFIG_SPACE_SIZE, DMA_FROM_DEVICE);
> +	if (dma_mapping_error(dma_dev, dst)) {
> +		dev_err(mali_c55->dev, "failed to map DMA addr\n");
> +		return -EIO;
> +	}
> +
> +	ret = mali_c55_dma_xfer(ctx, src, dst, DMA_FROM_DEVICE);
> +	dma_unmap_single(dma_dev, dst, MALI_C55_CONFIG_SPACE_SIZE,
> +			 DMA_FROM_DEVICE);
> +
> +	return ret;
> +}
> +
> +static int mali_c55_dma_write(struct mali_c55_ctx *ctx,
> +		       enum mali_c55_config_spaces cfg_space)
> +{
> +	struct mali_c55 *mali_c55 = ctx->mali_c55;
> +	struct device *dma_dev = mali_c55->channel->device->dev;
> +	dma_addr_t dst = ctx->base + config_space_addrs[cfg_space];
> +	dma_addr_t src;
> +	int ret;
> +
> +	guard(spinlock)(&ctx->lock);
> +
> +	src = dma_map_single(dma_dev, ctx->registers,
> +			     MALI_C55_CONFIG_SPACE_SIZE, DMA_TO_DEVICE);
> +	if (dma_mapping_error(dma_dev, src)) {
> +		dev_err(mali_c55->dev, "failed to map DMA addr\n");
> +		return -EIO;
> +	}
> +
> +	ret = mali_c55_dma_xfer(ctx, src, dst, DMA_TO_DEVICE);
> +	dma_unmap_single(dma_dev, src, MALI_C55_CONFIG_SPACE_SIZE,
> +			 DMA_TO_DEVICE);
> +
> +	return ret;
> +}
> +
> +static int mali_c55_config_read(struct mali_c55_ctx *ctx,
> +				enum mali_c55_config_spaces cfg_space)
> +{
> +	struct mali_c55 *mali_c55 = ctx->mali_c55;
> +
> +	if (mali_c55->channel) {
> +		return mali_c55_dma_read(ctx, cfg_space);
> +	} else {
> +		memcpy_fromio(ctx->registers,
> +			      mali_c55->base + config_space_addrs[cfg_space],
> +			      MALI_C55_CONFIG_SPACE_SIZE);
> +		return 0;
> +	}
> +}
> +
> +int mali_c55_config_write(struct mali_c55_ctx *ctx,
> +			  enum mali_c55_config_spaces cfg_space)
> +{
> +	struct mali_c55 *mali_c55 = ctx->mali_c55;
> +
> +	if (mali_c55->channel) {
> +		return mali_c55_dma_write(ctx, cfg_space);
> +	} else {
> +		memcpy_toio(mali_c55->base + config_space_addrs[cfg_space],
> +			    ctx->registers, MALI_C55_CONFIG_SPACE_SIZE);
> +		return 0;
> +	}
> +}
> +
> +struct mali_c55_ctx *mali_c55_get_active_context(struct mali_c55 *mali_c55)
> +{

It might be useful to check you're holding the mutex or spinlock used to
serialise access to the list. I don't think you acquire it e.g. when
calling isp_start.

> +	return list_first_entry(&mali_c55->contexts, struct mali_c55_ctx, list);
> +}
> +
> +static void mali_c55_remove_links(struct mali_c55 *mali_c55)
> +{
> +	unsigned int i;
> +
> +	media_entity_remove_links(&mali_c55->tpg.sd.entity);
> +	media_entity_remove_links(&mali_c55->isp.sd.entity);
> +
> +	for (i = 0; i < MALI_C55_NUM_RZRS; i++)
> +		media_entity_remove_links(&mali_c55->resizers[i].sd.entity);
> +
> +	for (i = 0; i < MALI_C55_NUM_CAP_DEVS; i++)
> +		media_entity_remove_links(&mali_c55->cap_devs[i].vdev.entity);
> +}
> +
> +static int mali_c55_create_links(struct mali_c55 *mali_c55)
> +{
> +	int ret;
> +
> +	/* Test pattern generator to ISP */
> +	ret = media_create_pad_link(&mali_c55->tpg.sd.entity, 0,
> +				    &mali_c55->isp.sd.entity,
> +				    MALI_C55_ISP_PAD_SINK_VIDEO, 0);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "failed to link TPG and ISP\n");
> +		goto err_remove_links;
> +	}
> +
> +	/* Full resolution resizer pipe. */
> +	ret = media_create_pad_link(&mali_c55->isp.sd.entity,
> +			MALI_C55_ISP_PAD_SOURCE,
> +			&mali_c55->resizers[MALI_C55_RZR_FR].sd.entity,
> +			MALI_C55_RZR_SINK_PAD,
> +			MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "failed to link ISP and FR resizer\n");
> +		goto err_remove_links;
> +	}
> +
> +	/* Full resolution bypass. */
> +	ret = media_create_pad_link(&mali_c55->isp.sd.entity,
> +				    MALI_C55_ISP_PAD_SOURCE_BYPASS,
> +				    &mali_c55->resizers[MALI_C55_RZR_FR].sd.entity,
> +				    MALI_C55_RZR_SINK_BYPASS_PAD,
> +				    MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "failed to link ISP and FR resizer\n");
> +		goto err_remove_links;
> +	}
> +
> +	/* Resizer pipe to video capture nodes. */
> +	ret = media_create_pad_link(&mali_c55->resizers[0].sd.entity,
> +			MALI_C55_RZR_SOURCE_PAD,
> +			&mali_c55->cap_devs[MALI_C55_CAP_DEV_FR].vdev.entity,
> +			0, MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
> +	if (ret) {
> +		dev_err(mali_c55->dev,
> +			"failed to link FR resizer and video device\n");
> +		goto err_remove_links;
> +	}
> +
> +	/* The downscale pipe is an optional hardware block */
> +	if (mali_c55->capabilities & MALI_C55_GPS_DS_PIPE_FITTED) {
> +		ret = media_create_pad_link(&mali_c55->isp.sd.entity,
> +			MALI_C55_ISP_PAD_SOURCE,
> +			&mali_c55->resizers[MALI_C55_RZR_DS].sd.entity,
> +			MALI_C55_RZR_SINK_PAD,
> +			MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
> +		if (ret) {
> +			dev_err(mali_c55->dev,
> +				"failed to link ISP and DS resizer\n");
> +			goto err_remove_links;
> +		}
> +
> +		ret = media_create_pad_link(&mali_c55->resizers[1].sd.entity,
> +			MALI_C55_RZR_SOURCE_PAD,
> +			&mali_c55->cap_devs[MALI_C55_CAP_DEV_DS].vdev.entity,
> +			0, MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
> +		if (ret) {
> +			dev_err(mali_c55->dev,
> +				"failed to link DS resizer and video device\n");
> +			goto err_remove_links;
> +		}
> +	}
> +
> +	return 0;
> +
> +err_remove_links:
> +	mali_c55_remove_links(mali_c55);
> +	return ret;
> +}
> +
> +static void mali_c55_unregister_entities(struct mali_c55 *mali_c55)
> +{
> +	mali_c55_unregister_tpg(mali_c55);
> +	mali_c55_unregister_isp(mali_c55);
> +	mali_c55_unregister_resizers(mali_c55);
> +	mali_c55_unregister_capture_devs(mali_c55);
> +}
> +
> +static int mali_c55_register_entities(struct mali_c55 *mali_c55)
> +{
> +	int ret;
> +
> +	ret = mali_c55_register_tpg(mali_c55);
> +	if (ret)
> +		return ret;
> +
> +	ret = mali_c55_register_isp(mali_c55);
> +	if (ret)
> +		goto err_unregister_entities;
> +
> +	ret = mali_c55_register_resizers(mali_c55);
> +	if (ret)
> +		goto err_unregister_entities;
> +
> +	ret = mali_c55_register_capture_devs(mali_c55);
> +	if (ret)
> +		goto err_unregister_entities;
> +
> +	ret = mali_c55_create_links(mali_c55);
> +	if (ret)
> +		goto err_unregister_entities;
> +
> +	return 0;
> +
> +err_unregister_entities:
> +	mali_c55_unregister_entities(mali_c55);
> +
> +	return ret;
> +}
> +
> +static u32 mali_c55_check_hwcfg(struct mali_c55 *mali_c55)
> +{
> +	u32 product, version, revision, capabilities;
> +
> +	product = mali_c55_read(mali_c55, MALI_C55_REG_PRODUCT, false);
> +	version = mali_c55_read(mali_c55, MALI_C55_REG_VERSION, false);
> +	revision = mali_c55_read(mali_c55, MALI_C55_REG_REVISION, false);
> +
> +	dev_info(mali_c55->dev, "Detected Mali-C55 ISP %u.%u.%u\n",
> +		 product, version, revision);
> +
> +	capabilities = mali_c55_read(mali_c55,
> +				     MALI_C55_REG_GLOBAL_PARAMETER_STATUS,
> +				     false);
> +	mali_c55->capabilities = (capabilities & 0xffff);
> +
> +	/* TODO: Might as well start some debugfs */
> +	dev_info(mali_c55->dev, "Mali-C55 capabilities: 0x%04x\n", capabilities);
> +	return version;
> +}
> +
> +static void mali_c55_swap_next_config(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
> +	u32 curr_config, next_config;
> +
> +	curr_config = mali_c55_read(mali_c55, MALI_C55_REG_PING_PONG_READ, false);
> +	curr_config = (curr_config & MALI_C55_REG_PING_PONG_READ_MASK) >> 2;

It'd be nice to have a name for 2.

> +	next_config = ~curr_config & 1;

Maybe:

	next_config = curr_config ^ 1;

> +
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_MCU_CONFIG,
> +			     MALI_C55_REG_MCU_CONFIG_WRITE_MASK, next_config);
> +	mali_c55_config_write(ctx, next_config ?
> +			      MALI_C55_CONFIG_PING : MALI_C55_CONFIG_PONG);
> +}
> +
> +static irqreturn_t mali_c55_isr(int irq, void *context)
> +{
> +	struct device *dev = context;
> +	struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
> +	u32 interrupt_status;
> +	unsigned int i, j;
> +
> +	interrupt_status = mali_c55_read(mali_c55,
> +					 MALI_C55_REG_INTERRUPT_STATUS_VECTOR,
> +					 false);
> +	if (!interrupt_status)
> +		return IRQ_NONE;
> +
> +	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_CLEAR_VECTOR,
> +		       interrupt_status);
> +	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_CLEAR, 0);
> +	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_CLEAR, 1);
> +
> +	for (i = 0; i < MALI_C55_NUM_IRQ_BITS; i++) {
> +		if (!(interrupt_status & (1 << i)))
> +			continue;
> +
> +		switch (i) {
> +		case MALI_C55_IRQ_ISP_START:
> +			mali_c55_isp_queue_event_sof(mali_c55);
> +
> +			for (j = i; j < MALI_C55_NUM_CAP_DEVS; j++)
> +				mali_c55_set_next_buffer(&mali_c55->cap_devs[j]);
> +
> +			mali_c55_swap_next_config(mali_c55);
> +
> +			break;
> +		case MALI_C55_IRQ_ISP_DONE:
> +			/*
> +			 * TODO: Where the ISP has no Pong config fitted, we'd
> +			 * have to do the mali_c55_swap_next_config() call here.
> +			 */
> +			mali_c55->isp.frame_sequence++;
> +			break;
> +		case MALI_C55_IRQ_FR_Y_DONE:
> +			mali_c55_set_plane_done(
> +				&mali_c55->cap_devs[MALI_C55_CAP_DEV_FR],
> +				MALI_C55_PLANE_Y);
> +			break;
> +		case MALI_C55_IRQ_FR_UV_DONE:
> +			mali_c55_set_plane_done(
> +				&mali_c55->cap_devs[MALI_C55_CAP_DEV_FR],
> +				MALI_C55_PLANE_UV);
> +			break;
> +		case MALI_C55_IRQ_DS_Y_DONE:
> +			mali_c55_set_plane_done(
> +				&mali_c55->cap_devs[MALI_C55_CAP_DEV_DS],
> +				MALI_C55_PLANE_Y);
> +			break;
> +		case MALI_C55_IRQ_DS_UV_DONE:
> +			mali_c55_set_plane_done(
> +				&mali_c55->cap_devs[MALI_C55_CAP_DEV_DS],
> +				MALI_C55_PLANE_UV);
> +			break;
> +		default:
> +			/*
> +			 * Only the above interrupts are currently unmasked. If
> +			 * we receive anything else here then something weird
> +			 * has gone on.
> +			 */
> +			dev_err(dev, "masked interrupt %s triggered\n",
> +				mali_c55_interrupt_names[i]);
> +		}
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int mali_c55_init_context(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_ctx *ctx;
> +	int ret;
> +
> +	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx) {
> +		dev_err(mali_c55->dev, "failed to allocate new context\n");
> +		return -ENOMEM;
> +	}
> +
> +	ctx->base = mali_c55->res->start;
> +	ctx->mali_c55 = mali_c55;
> +
> +	ctx->registers = kzalloc(MALI_C55_CONFIG_SPACE_SIZE,
> +				 GFP_KERNEL | GFP_DMA);
> +	if (!ctx->registers) {
> +		ret = -ENOMEM;
> +		goto err_free_ctx;
> +	}
> +
> +	/*
> +	 * The allocated memory is empty, we need to load the default
> +	 * register settings. We just read Ping; it's identical to Pong.
> +	 */
> +	ret = mali_c55_config_read(ctx, MALI_C55_CONFIG_PING);
> +	if (ret)
> +		goto err_free_registers;
> +
> +	list_add_tail(&ctx->list, &mali_c55->contexts);
> +
> +	return 0;
> +
> +err_free_registers:
> +	kfree(ctx->registers);
> +err_free_ctx:
> +	kfree(ctx);
> +
> +	return ret;
> +}
> +
> +static int mali_c55_runtime_resume(struct device *dev)
> +{
> +	struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = clk_bulk_prepare_enable(ARRAY_SIZE(mali_c55->clks),
> +				      mali_c55->clks);
> +	if (ret)
> +		dev_err(mali_c55->dev, "failed to enable clocks\n");
> +
> +	return ret;
> +}
> +
> +static int mali_c55_runtime_suspend(struct device *dev)
> +{
> +	struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
> +
> +	clk_bulk_disable_unprepare(ARRAY_SIZE(mali_c55->clks), mali_c55->clks);
> +	return 0;
> +}
> +
> +static const struct dev_pm_ops mali_c55_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> +				pm_runtime_force_resume)
> +	SET_RUNTIME_PM_OPS(mali_c55_runtime_suspend, mali_c55_runtime_resume,
> +			   NULL)
> +};
> +
> +static int mali_c55_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct mali_c55 *mali_c55;
> +	dma_cap_mask_t mask;
> +	u32 version;
> +	int ret;
> +	u32 val;
> +
> +	mali_c55 = devm_kzalloc(dev, sizeof(*mali_c55), GFP_KERNEL);
> +	if (!mali_c55)
> +		return dev_err_probe(dev, -ENOMEM,
> +				     "failed to allocate memory\n");
> +
> +	mali_c55->dev = dev;
> +	platform_set_drvdata(pdev, mali_c55);
> +
> +	mali_c55->base = devm_platform_get_and_ioremap_resource(pdev, 0,
> +								&mali_c55->res);
> +	if (IS_ERR(mali_c55->base))
> +		return dev_err_probe(dev, PTR_ERR(mali_c55->base),
> +				     "failed to map IO memory\n");
> +
> +	ret = platform_get_irq(pdev, 0);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "failed to get interrupt num\n");
> +
> +	ret = devm_request_threaded_irq(&pdev->dev, ret, NULL,
> +					mali_c55_isr, IRQF_ONESHOT,
> +					dev_driver_string(&pdev->dev),
> +					&pdev->dev);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to request irq\n");
> +
> +	for (unsigned int i = 0; i < ARRAY_SIZE(mali_c55_clk_names); i++)
> +		mali_c55->clks[i].id = mali_c55_clk_names[i];
> +
> +	ret = devm_clk_bulk_get(dev, ARRAY_SIZE(mali_c55->clks), mali_c55->clks);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to acquire clocks\n");
> +
> +	pm_runtime_enable(&pdev->dev);
> +
> +	ret = pm_runtime_resume_and_get(&pdev->dev);
> +	if (ret)
> +		goto err_pm_runtime_disable;
> +
> +	of_reserved_mem_device_init(dev);
> +	version = mali_c55_check_hwcfg(mali_c55);
> +	vb2_dma_contig_set_max_seg_size(dev, UINT_MAX);
> +
> +	/* Use "software only" context management. */
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_MCU_CONFIG,
> +			     MALI_C55_REG_MCU_CONFIG_OVERRIDE_MASK,
> +			     MALI_C55_REG_MCU_CONFIG_OVERRIDE_MASK);
> +
> +	dma_cap_zero(mask);
> +	dma_cap_set(DMA_MEMCPY, mask);
> +
> +	/*
> +	 * No error check, because we will just fallback on memcpy if there is
> +	 * no usable DMA channel on the system.
> +	 */
> +	mali_c55->channel = dma_request_channel(mask, NULL, NULL);
> +
> +	INIT_LIST_HEAD(&mali_c55->contexts);
> +	ret = mali_c55_init_context(mali_c55);
> +	if (ret)
> +		goto err_release_dma_channel;
> +
> +	mali_c55->media_dev.dev = dev;
> +	strscpy(mali_c55->media_dev.model, "ARM Mali-C55 ISP",
> +		sizeof(mali_c55->media_dev.model));
> +	mali_c55->media_dev.hw_revision = version;
> +
> +	media_device_init(&mali_c55->media_dev);
> +	ret = media_device_register(&mali_c55->media_dev);
> +	if (ret)
> +		goto err_cleanup_media_device;
> +
> +	mali_c55->v4l2_dev.mdev = &mali_c55->media_dev;
> +	ret = v4l2_device_register(dev, &mali_c55->v4l2_dev);
> +	if (ret) {
> +		dev_err(dev, "failed to register V4L2 device\n");
> +		goto err_unregister_media_device;
> +	};
> +
> +	ret = mali_c55_register_entities(mali_c55);
> +	if (ret) {
> +		dev_err(dev, "failed to register entities\n");
> +		goto err_unregister_v4l2_device;
> +	}
> +
> +	/* Set safe stop to ensure we're in a non-streaming state */
> +	mali_c55_write(mali_c55, MALI_C55_REG_INPUT_MODE_REQUEST,
> +		       MALI_C55_INPUT_SAFE_STOP);
> +	readl_poll_timeout(mali_c55->base + MALI_C55_REG_MODE_STATUS,
> +			   val, !val, 10 * USEC_PER_MSEC, 250 * USEC_PER_MSEC);
> +
> +	/*
> +	 * For now, few of the ISP's features are supported (pretty much just
> +	 * debayering and the colour space conversion). Flag the others as being
> +	 * bypassed so that they don't interfere.
> +	 *
> +	 * TODO: Support more features!
> +	 */
> +	mali_c55_write(mali_c55, 0x18eac, 0x3c);
> +	mali_c55_write(mali_c55, 0x18eb0, 0xf);
> +	mali_c55_write(mali_c55, 0x18eb8, 0x3);
> +	mali_c55_write(mali_c55, 0x18ebc, 0x7b);
> +	mali_c55_write(mali_c55, 0x18ec0, 0x38);
> +	mali_c55_write(mali_c55, MALI_C55_REG_FR_BYPASS, 0xf);
> +	mali_c55_write(mali_c55, MALI_C55_REG_DS_BYPASS, 0xf);
> +
> +	/*
> +	 * We're ready to process interrupts. Clear any that are set and then
> +	 * unmask them for processing.
> +	 */
> +	mali_c55_write(mali_c55, 0x30, 0xffffffff);
> +	mali_c55_write(mali_c55, 0x34, 0xffffffff);
> +	mali_c55_write(mali_c55, 0x40, 0x01);
> +	mali_c55_write(mali_c55, 0x40, 0x00);
> +	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_MASK_VECTOR, 0x39fc3fc);
> +
> +	pm_runtime_put(&pdev->dev);
> +
> +	return 0;
> +
> +err_unregister_v4l2_device:
> +	v4l2_device_unregister(&mali_c55->v4l2_dev);
> +err_unregister_media_device:
> +	media_device_unregister(&mali_c55->media_dev);
> +err_cleanup_media_device:
> +	media_device_cleanup(&mali_c55->media_dev);
> +err_release_dma_channel:
> +	dma_release_channel(mali_c55->channel);
> +err_pm_runtime_disable:
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return ret;
> +}
> +
> +static void mali_c55_remove(struct platform_device *pdev)
> +{
> +	struct mali_c55 *mali_c55 = platform_get_drvdata(pdev);
> +	struct mali_c55_ctx *ctx, *tmp;
> +
> +	list_for_each_entry_safe(ctx, tmp, &mali_c55->contexts, list) {
> +		list_del(&ctx->list);
> +		kfree(ctx->registers);
> +		kfree(ctx);
> +	}
> +
> +	mali_c55_remove_links(mali_c55);
> +	mali_c55_unregister_entities(mali_c55);
> +	v4l2_device_put(&mali_c55->v4l2_dev);
> +	media_device_unregister(&mali_c55->media_dev);
> +	media_device_cleanup(&mali_c55->media_dev);
> +	dma_release_channel(mali_c55->channel);
> +}
> +
> +static const struct of_device_id mali_c55_of_match[] = {
> +	{
> +		.compatible = "arm,mali-c55",
> +	},

Fits on a single line.

> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, mali_c55_of_match);
> +
> +static struct platform_driver mali_c55_driver = {
> +	.driver = {
> +		.name = "mali-c55",
> +		.of_match_table = of_match_ptr(mali_c55_of_match),
> +		.pm = &mali_c55_pm_ops,
> +	},
> +	.probe = mali_c55_probe,
> +	.remove_new = mali_c55_remove,
> +};
> +
> +module_platform_driver(mali_c55_driver);
> +MODULE_AUTHOR("Daniel Scally <[e-mail]>");
> +MODULE_AUTHOR("Jacopo Mondi <[e-mail]>");
> +MODULE_DESCRIPTION("ARM Mali-C55 ISP platform driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-isp.c b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
> new file mode 100644
> index 000000000000..a41b02882c50
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
> @@ -0,0 +1,701 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ARM Mali-C55 ISP Driver - Image signal processor
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/iopoll.h>
> +#include <linux/property.h>
> +#include <linux/string.h>
> +
> +#include <media/media-entity.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-mc.h>
> +#include <media/v4l2-subdev.h>
> +
> +#include "mali-c55-common.h"
> +#include "mali-c55-registers.h"
> +
> +static const struct mali_c55_isp_fmt mali_c55_isp_fmts[] = {
> +	{
> +		.code = MEDIA_BUS_FMT_SRGGB8_1X8,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
> +		.order = MALI_C55_BAYER_ORDER_RGGB,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGRBG8_1X8,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
> +		.order = MALI_C55_BAYER_ORDER_GRBG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGBRG8_1X8,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
> +		.order = MALI_C55_BAYER_ORDER_GBRG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SBGGR8_1X8,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
> +		.order = MALI_C55_BAYER_ORDER_BGGR,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SRGGB10_1X10,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
> +		.order = MALI_C55_BAYER_ORDER_RGGB,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
> +		.order = MALI_C55_BAYER_ORDER_GRBG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGBRG10_1X10,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
> +		.order = MALI_C55_BAYER_ORDER_GBRG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SBGGR10_1X10,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
> +		.order = MALI_C55_BAYER_ORDER_BGGR,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SRGGB12_1X12,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
> +		.order = MALI_C55_BAYER_ORDER_RGGB,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGRBG12_1X12,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
> +		.order = MALI_C55_BAYER_ORDER_GRBG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGBRG12_1X12,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
> +		.order = MALI_C55_BAYER_ORDER_GBRG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SBGGR12_1X12,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
> +		.order = MALI_C55_BAYER_ORDER_BGGR,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SRGGB14_1X14,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
> +		.order = MALI_C55_BAYER_ORDER_RGGB,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGRBG14_1X14,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
> +		.order = MALI_C55_BAYER_ORDER_GRBG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGBRG14_1X14,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
> +		.order = MALI_C55_BAYER_ORDER_GBRG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SBGGR14_1X14,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
> +		.order = MALI_C55_BAYER_ORDER_BGGR,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SRGGB16_1X16,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
> +		.order = MALI_C55_BAYER_ORDER_RGGB,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGRBG16_1X16,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
> +		.order = MALI_C55_BAYER_ORDER_GRBG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SGBRG16_1X16,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
> +		.order = MALI_C55_BAYER_ORDER_GBRG,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_SBGGR16_1X16,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
> +		.order = MALI_C55_BAYER_ORDER_BGGR,
> +		.encoding = V4L2_PIXEL_ENC_BAYER,
> +	},
> +	{
> +		.code = MEDIA_BUS_FMT_RGB202020_1X60,
> +		.bitwidth = MALI_C55_INPUT_WIDTH_20BIT,
> +		.order = 0, /* Not relevant for this format */
> +		.encoding = V4L2_PIXEL_ENC_RGB,
> +	}
> +	/*
> +	 * TODO: Support MEDIA_BUS_FMT_YUV20_1X60 here. This is so that we can
> +	 * also support YUV input from a sensor passed-through to the output. At
> +	 * present we have no mechanism to test that though so it may have to
> +	 * wait a while...
> +	 */
> +};
> +
> +const struct mali_c55_isp_fmt *
> +mali_c55_isp_fmt_next(const struct mali_c55_isp_fmt *fmt)
> +{
> +	if (!fmt)
> +		fmt = &mali_c55_isp_fmts[0];
> +	else
> +		fmt++;
> +
> +	for (; fmt < &mali_c55_isp_fmts[ARRAY_SIZE(mali_c55_isp_fmts)]; fmt++)
> +		return fmt;
> +
> +	return NULL;
> +}
> +
> +bool mali_c55_isp_is_format_supported(unsigned int mbus_code)
> +{
> +	const struct mali_c55_isp_fmt *isp_fmt;
> +
> +	for_each_mali_isp_fmt(isp_fmt) {
> +		if (isp_fmt->code == mbus_code)
> +			return true;
> +	}
> +
> +	return false;
> +}
> +
> +static const struct mali_c55_isp_fmt *
> +mali_c55_isp_get_mbus_config_by_code(u32 code)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55_isp_fmts); i++) {
> +		if (mali_c55_isp_fmts[i].code == code)
> +			return &mali_c55_isp_fmts[i];
> +	}
> +
> +	return NULL;
> +}
> +
> +static void mali_c55_isp_stop(struct mali_c55 *mali_c55)
> +{
> +	u32 val;
> +
> +	mali_c55_write(mali_c55, MALI_C55_REG_INPUT_MODE_REQUEST, MALI_C55_INPUT_SAFE_STOP);
> +	readl_poll_timeout(mali_c55->base + MALI_C55_REG_MODE_STATUS,
> +			   val, !val, 10 * USEC_PER_MSEC, 250 * USEC_PER_MSEC);
> +}
> +
> +static int mali_c55_isp_start(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
> +	const struct mali_c55_isp_fmt *cfg;
> +	struct v4l2_mbus_framefmt *format;
> +	struct v4l2_subdev_state *state;
> +	struct v4l2_rect *crop;
> +	struct v4l2_subdev *sd;
> +	u32 val;
> +	int ret;
> +
> +	sd = &mali_c55->isp.sd;
> +
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_MCU_CONFIG,
> +			     MALI_C55_REG_MCU_CONFIG_WRITE_MASK, 0x01);
> +
> +	/* Apply input windowing */
> +	state = v4l2_subdev_get_locked_active_state(sd);
> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
> +	format = v4l2_subdev_state_get_format(state,
> +					      MALI_C55_ISP_PAD_SINK_VIDEO);
> +	cfg = mali_c55_isp_get_mbus_config_by_code(format->code);
> +
> +	mali_c55_write(mali_c55, MALI_C55_REG_HC_START,
> +		       MALI_C55_HC_START(crop->left));
> +	mali_c55_write(mali_c55, MALI_C55_REG_HC_SIZE,
> +		       MALI_C55_HC_SIZE(crop->width));
> +	mali_c55_write(mali_c55, MALI_C55_REG_VC_START_SIZE,
> +		       MALI_C55_VC_START(crop->top) |
> +		       MALI_C55_VC_SIZE(crop->height));
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_BASE_ADDR,
> +			     MALI_C55_REG_ACTIVE_WIDTH_MASK, format->width);
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_BASE_ADDR,
> +			     MALI_C55_REG_ACTIVE_HEIGHT_MASK, format->height);
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_BAYER_ORDER,
> +			     MALI_C55_BAYER_ORDER_MASK, cfg->order);
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_INPUT_WIDTH,
> +			     MALI_C55_INPUT_WIDTH_MASK, cfg->bitwidth);
> +
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
> +			     MALI_C55_ISP_RAW_BYPASS_BYPASS_MASK,
> +			     cfg->encoding == V4L2_PIXEL_ENC_RGB ?
> +			     MALI_C55_ISP_RAW_BYPASS_BYPASS_MASK : 0x00);
> +
> +	ret = mali_c55_config_write(ctx, MALI_C55_CONFIG_PING);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "failed to DMA config\n");
> +		return ret;
> +	}
> +
> +	mali_c55_write(mali_c55, MALI_C55_REG_INPUT_MODE_REQUEST,
> +		       MALI_C55_INPUT_SAFE_START);
> +	readl_poll_timeout(mali_c55->base + MALI_C55_REG_MODE_STATUS,
> +			   val, !val, 10 * USEC_PER_MSEC, 250 * USEC_PER_MSEC);
> +
> +	return 0;
> +}
> +
> +int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable)

Have you considered {enable,disable}_streams? All new drivers should use
these instead of s_stream() now.

> +{
> +	struct mali_c55 *mali_c55 = isp->mali_c55;
> +	struct media_pad *source_pad;
> +	struct media_pad *sink_pad;
> +	int ret;
> +
> +	if (!enable) {
> +		if (isp->source)
> +			v4l2_subdev_call(isp->source, video, s_stream, false);
> +		isp->source = NULL;
> +
> +		mali_c55_isp_stop(mali_c55);
> +
> +		return 0;
> +	}
> +
> +	sink_pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
> +	source_pad = media_pad_remote_pad_unique(sink_pad);
> +	if (IS_ERR(source_pad)) {
> +		dev_err(mali_c55->dev, "Failed to get source for ISP\n");
> +		return PTR_ERR(source_pad);
> +	}
> +
> +	isp->source = media_entity_to_v4l2_subdev(source_pad->entity);
> +
> +	isp->frame_sequence = 0;
> +	ret = mali_c55_isp_start(mali_c55);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "Failed to start ISP\n");
> +		isp->source = NULL;
> +		return ret;
> +	}
> +
> +	ret = v4l2_subdev_call(isp->source, video, s_stream, true);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "Failed to start ISP source\n");
> +		mali_c55_isp_stop(mali_c55);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int mali_c55_isp_enum_mbus_code(struct v4l2_subdev *sd,
> +				       struct v4l2_subdev_state *state,
> +				       struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	/*
> +	 * Only the internal RGB processed format is allowed on the regular
> +	 * processing source pad.
> +	 */
> +	if (code->pad == MALI_C55_ISP_PAD_SOURCE) {
> +		if (code->index)
> +			return -EINVAL;
> +
> +		code->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +		return 0;
> +	}
> +
> +	/* On the sink and bypass pads all the supported formats are allowed. */
> +	if (code->index >= ARRAY_SIZE(mali_c55_isp_fmts))
> +		return -EINVAL;
> +
> +	code->code = mali_c55_isp_fmts[code->index].code;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_isp_enum_frame_size(struct v4l2_subdev *sd,
> +					struct v4l2_subdev_state *state,
> +					struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	const struct mali_c55_isp_fmt *cfg;
> +
> +	if (fse->index > 0)
> +		return -EINVAL;
> +
> +	/*
> +	 * Only the internal RGB processed format is allowed on the regular
> +	 * processing source pad.
> +	 *
> +	 * On the sink and bypass pads all the supported formats are allowed.
> +	 */
> +	if (fse->pad == MALI_C55_ISP_PAD_SOURCE) {
> +		if (fse->code != MEDIA_BUS_FMT_RGB121212_1X36)
> +			return -EINVAL;
> +	} else {
> +		cfg = mali_c55_isp_get_mbus_config_by_code(fse->code);
> +		if (!cfg)
> +			return -EINVAL;
> +	}
> +
> +	fse->min_width = MALI_C55_MIN_WIDTH;
> +	fse->min_height = MALI_C55_MIN_HEIGHT;
> +	fse->max_width = MALI_C55_MAX_WIDTH;
> +	fse->max_height = MALI_C55_MAX_HEIGHT;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_isp_set_fmt(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *state,
> +				struct v4l2_subdev_format *format)
> +{
> +	struct v4l2_mbus_framefmt *fmt = &format->format;
> +	const struct mali_c55_isp_fmt *cfg;
> +	struct v4l2_mbus_framefmt *src_fmt;
> +	struct v4l2_rect *crop;
> +
> +	/*
> +	 * Disallow set_fmt on the source pads; format is fixed and the sizes
> +	 * are the result of applying the sink crop rectangle to the sink
> +	 * format.
> +	 */
> +	if (format->pad)
> +		return v4l2_subdev_get_fmt(sd, state, format);
> +
> +	cfg = mali_c55_isp_get_mbus_config_by_code(fmt->code);
> +	if (!cfg)
> +		fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
> +	fmt->field = V4L2_FIELD_NONE;
> +
> +	/*
> +	 * Clamp sizes in the accepted limits and clamp the crop rectangle in
> +	 * the new sizes.
> +	 */
> +	clamp_t(unsigned int, fmt->width,
> +		MALI_C55_MIN_WIDTH, MALI_C55_MAX_WIDTH);
> +	clamp_t(unsigned int, fmt->width,
> +		MALI_C55_MIN_HEIGHT, MALI_C55_MAX_HEIGHT);
> +
> +	*v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SINK_VIDEO) = *fmt;

Over 80 for no apparent reason.

> +
> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
> +	crop->left = 0;
> +	crop->top = 0;
> +	crop->width = fmt->width;
> +	crop->height = fmt->height;
> +
> +	/*
> +	 * Propagate format to source pads. On the 'regular' output pad use
> +	 * the internal RGB processed format, while on the bypass pad simply
> +	 * replicate the ISP sink format. The sizes on both pads are the same as
> +	 * the ISP sink crop rectangle.
> +	 */
> +	src_fmt = v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SOURCE);
> +	src_fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +	src_fmt->width = crop->width;
> +	src_fmt->height = crop->height;
> +
> +	src_fmt = v4l2_subdev_state_get_format(state,
> +					       MALI_C55_ISP_PAD_SOURCE_BYPASS);
> +	src_fmt->code = fmt->code;
> +	src_fmt->width = crop->width;
> +	src_fmt->height = crop->height;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_isp_get_selection(struct v4l2_subdev *sd,
> +				      struct v4l2_subdev_state *state,
> +				      struct v4l2_subdev_selection *sel)
> +{
> +	if (sel->pad || sel->target != V4L2_SEL_TGT_CROP)
> +		return -EINVAL;
> +
> +	sel->r = *v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
> +
> +	return 0;
> +}
> +
> +static int mali_c55_isp_set_selection(struct v4l2_subdev *sd,
> +				      struct v4l2_subdev_state *state,
> +				      struct v4l2_subdev_selection *sel)
> +{
> +	struct v4l2_mbus_framefmt *src_fmt;
> +	struct v4l2_mbus_framefmt *fmt;
> +	struct v4l2_rect *crop;
> +
> +	if (sel->pad || sel->target != V4L2_SEL_TGT_CROP)
> +		return -EINVAL;
> +
> +	fmt = v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SINK_VIDEO);
> +
> +	clamp_t(unsigned int, sel->r.left, 0, fmt->width);
> +	clamp_t(unsigned int, sel->r.top, 0, fmt->height);
> +	clamp_t(unsigned int, sel->r.width, MALI_C55_MIN_WIDTH,
> +		fmt->width - sel->r.left);
> +	clamp_t(unsigned int, sel->r.height, MALI_C55_MIN_HEIGHT,
> +		fmt->height - sel->r.top);
> +
> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
> +	*crop = sel->r;
> +
> +	/* Propagate the crop rectangle sizes to the source pad format. */
> +	src_fmt = v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SOURCE);
> +	src_fmt->width = crop->width;
> +	src_fmt->height = crop->height;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_pad_ops mali_c55_isp_pad_ops = {
> +	.enum_mbus_code		= mali_c55_isp_enum_mbus_code,
> +	.enum_frame_size	= mali_c55_isp_enum_frame_size,
> +	.get_fmt		= v4l2_subdev_get_fmt,
> +	.set_fmt		= mali_c55_isp_set_fmt,
> +	.get_selection		= mali_c55_isp_get_selection,
> +	.set_selection		= mali_c55_isp_set_selection,
> +	.link_validate		= v4l2_subdev_link_validate_default,
> +};
> +
> +void mali_c55_isp_queue_event_sof(struct mali_c55 *mali_c55)
> +{
> +	struct v4l2_event event = {
> +		.type = V4L2_EVENT_FRAME_SYNC,
> +	};
> +
> +	event.u.frame_sync.frame_sequence = mali_c55->isp.frame_sequence;
> +	v4l2_event_queue(mali_c55->isp.sd.devnode, &event);
> +}
> +
> +static int
> +mali_c55_isp_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
> +			     struct v4l2_event_subscription *sub)
> +{
> +	if (sub->type != V4L2_EVENT_FRAME_SYNC)
> +		return -EINVAL;
> +
> +	/* V4L2_EVENT_FRAME_SYNC doesn't require an id, so zero should be set */
> +	if (sub->id != 0)
> +		return -EINVAL;
> +
> +	return v4l2_event_subscribe(fh, sub, 0, NULL);
> +}
> +
> +static const struct v4l2_subdev_core_ops mali_c55_isp_core_ops = {
> +	.subscribe_event = mali_c55_isp_subscribe_event,
> +	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
> +};
> +
> +static const struct v4l2_subdev_ops mali_c55_isp_ops = {
> +	.pad	= &mali_c55_isp_pad_ops,
> +	.core	= &mali_c55_isp_core_ops,
> +};
> +
> +static int mali_c55_isp_init_state(struct v4l2_subdev *sd,
> +				   struct v4l2_subdev_state *sd_state)
> +{
> +	struct v4l2_mbus_framefmt *sink_fmt, *src_fmt;
> +	struct v4l2_rect *in_crop;
> +
> +	sink_fmt = v4l2_subdev_state_get_format(sd_state,
> +						MALI_C55_ISP_PAD_SINK_VIDEO);
> +	src_fmt = v4l2_subdev_state_get_format(sd_state,
> +					       MALI_C55_ISP_PAD_SOURCE);
> +	in_crop = v4l2_subdev_state_get_crop(sd_state,
> +					     MALI_C55_ISP_PAD_SINK_VIDEO);
> +
> +	sink_fmt->width = MALI_C55_DEFAULT_WIDTH;
> +	sink_fmt->height = MALI_C55_DEFAULT_HEIGHT;
> +	sink_fmt->field = V4L2_FIELD_NONE;
> +	sink_fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
> +
> +	*v4l2_subdev_state_get_format(sd_state,
> +			      MALI_C55_ISP_PAD_SOURCE_BYPASS) = *sink_fmt;
> +
> +	src_fmt->width = MALI_C55_DEFAULT_WIDTH;
> +	src_fmt->height = MALI_C55_DEFAULT_HEIGHT;
> +	src_fmt->field = V4L2_FIELD_NONE;
> +	src_fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +
> +	in_crop->top = 0;
> +	in_crop->left = 0;
> +	in_crop->width = MALI_C55_DEFAULT_WIDTH;
> +	in_crop->height = MALI_C55_DEFAULT_HEIGHT;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_internal_ops mali_c55_isp_internal_ops = {
> +	.init_state = mali_c55_isp_init_state,
> +};
> +
> +static const struct media_entity_operations mali_c55_isp_media_ops = {
> +	.link_validate		= v4l2_subdev_link_validate,
> +};
> +
> +static int mali_c55_isp_notifier_bound(struct v4l2_async_notifier *notifier,
> +				       struct v4l2_subdev *subdev,
> +				       struct v4l2_async_connection *asc)
> +{
> +	struct mali_c55_isp *isp = container_of(notifier,
> +						struct mali_c55_isp, notifier);
> +	struct mali_c55 *mali_c55 = isp->mali_c55;
> +	struct media_pad *pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
> +	int ret;
> +
> +	/*
> +	 * By default we'll flag this link enabled and the TPG disabled, but
> +	 * no immutable flag because we need to be able to switch between the
> +	 * two.
> +	 */
> +	ret = v4l2_create_fwnode_links_to_pad(subdev, pad,
> +					      MEDIA_LNK_FL_ENABLED);
> +	if (ret)
> +		dev_err(mali_c55->dev, "failed to create link for %s\n",
> +			subdev->name);
> +
> +	return ret;
> +}
> +
> +static int mali_c55_isp_notifier_complete(struct v4l2_async_notifier *notifier)
> +{
> +	struct mali_c55_isp *isp = container_of(notifier,
> +						struct mali_c55_isp, notifier);
> +	struct mali_c55 *mali_c55 = isp->mali_c55;
> +
> +	return v4l2_device_register_subdev_nodes(&mali_c55->v4l2_dev);
> +}
> +
> +static const struct v4l2_async_notifier_operations mali_c55_isp_notifier_ops = {
> +	.bound = mali_c55_isp_notifier_bound,
> +	.complete = mali_c55_isp_notifier_complete,
> +};
> +
> +static int mali_c55_isp_parse_endpoint(struct mali_c55_isp *isp)
> +{
> +	struct mali_c55 *mali_c55 = isp->mali_c55;
> +	struct v4l2_async_connection *asc;
> +	struct fwnode_handle *ep;
> +	int ret;
> +
> +	v4l2_async_nf_init(&isp->notifier, &mali_c55->v4l2_dev);
> +
> +	/*
> +	 * The ISP should have a single endpoint pointing to some flavour of
> +	 * CSI-2 receiver...but for now at least we do want everything to work
> +	 * normally even with no sensors connected, as we have the TPG. If we
> +	 * don't find a sensor just warn and return success.
> +	 */
> +	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(mali_c55->dev),
> +					     0, 0, 0);
> +	if (!ep) {
> +		dev_warn(mali_c55->dev, "no local endpoint found\n");
> +		return 0;
> +	}
> +
> +	asc = v4l2_async_nf_add_fwnode_remote(&isp->notifier, ep,
> +					      struct v4l2_async_connection);
> +	if (IS_ERR(asc)) {
> +		dev_err(mali_c55->dev, "failed to add remote fwnode\n");
> +		ret = PTR_ERR(asc);
> +		goto err_put_ep;
> +	}
> +
> +	isp->notifier.ops = &mali_c55_isp_notifier_ops;
> +	ret = v4l2_async_nf_register(&isp->notifier);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "failed to register notifier\n");
> +		goto err_cleanup_nf;
> +	}
> +
> +	fwnode_handle_put(ep);
> +
> +	return 0;
> +
> +err_cleanup_nf:
> +	v4l2_async_nf_cleanup(&isp->notifier);
> +err_put_ep:
> +	fwnode_handle_put(ep);
> +
> +	return ret;
> +}
> +
> +int mali_c55_register_isp(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_isp *isp = &mali_c55->isp;
> +	struct v4l2_subdev *sd = &isp->sd;
> +	int ret;
> +
> +	isp->mali_c55 = mali_c55;
> +
> +	v4l2_subdev_init(sd, &mali_c55_isp_ops);
> +	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
> +	sd->entity.ops = &mali_c55_isp_media_ops;
> +	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_ISP;
> +	sd->owner = THIS_MODULE;

The owner will be set by v4l2_device_register_subdev() after
aa7b148855e8265c4f72ae0305842efdda72680b. You can drop this assignment.

Same for the other call sites.

> +	sd->internal_ops = &mali_c55_isp_internal_ops;
> +	strscpy(sd->name, MALI_C55_DRIVER_NAME " isp", sizeof(sd->name));
> +
> +	isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO].flags = MEDIA_PAD_FL_SINK;
> +	isp->pads[MALI_C55_ISP_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> +	isp->pads[MALI_C55_ISP_PAD_SOURCE_BYPASS].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&sd->entity, MALI_C55_ISP_NUM_PADS,
> +				     isp->pads);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_subdev_init_finalize(sd);
> +	if (ret)
> +		goto err_cleanup_media_entity;
> +
> +	ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
> +	if (ret)
> +		goto err_cleanup_subdev;
> +
> +	ret = mali_c55_isp_parse_endpoint(isp);
> +	if (ret)
> +		goto err_cleanup_subdev;
> +
> +	mutex_init(&isp->lock);
> +
> +	return 0;
> +
> +err_cleanup_subdev:
> +	v4l2_subdev_cleanup(sd);
> +err_cleanup_media_entity:
> +	media_entity_cleanup(&sd->entity);
> +	isp->mali_c55 = NULL;
> +
> +	return ret;
> +}
> +
> +void mali_c55_unregister_isp(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_isp *isp = &mali_c55->isp;
> +
> +	if (!isp->mali_c55)
> +		return;
> +
> +	mutex_destroy(&isp->lock);
> +	v4l2_async_nf_unregister(&isp->notifier);

You're missing v4l2_async_nf_cleanup().

> +	v4l2_device_unregister_subdev(&isp->sd);
> +	v4l2_subdev_cleanup(&isp->sd);
> +	media_entity_cleanup(&isp->sd.entity);
> +}
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-registers.h b/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
> new file mode 100644
> index 000000000000..9636f08544fa
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
> @@ -0,0 +1,180 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * ARM Mali-C55 ISP Driver - Register definitions
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#ifndef _MALI_C55_REGISTERS_H
> +#define _MALI_C55_REGISTERS_H
> +
> +#include <linux/bits.h>
> +
> +/* ISP Common 0x00000 - 0x000ff */
> +
> +#define MALI_C55_REG_API				0x00000
> +#define MALI_C55_REG_PRODUCT				0x00004
> +#define MALI_C55_REG_VERSION				0x00008
> +#define MALI_C55_REG_REVISION				0x0000c
> +#define MALI_C55_REG_PULSE_MODE				0x0003c
> +#define MALI_C55_REG_INPUT_MODE_REQUEST			0x0009c
> +#define MALI_C55_INPUT_SAFE_STOP			0x00
> +#define MALI_C55_INPUT_SAFE_START			0x01
> +#define MALI_C55_REG_MODE_STATUS			0x000a0
> +#define MALI_C55_REG_INTERRUPT_MASK_VECTOR		0x00030
> +#define MALI_C55_INTERRUPT_MASK_ALL			GENMASK(31, 0)
> +
> +#define MALI_C55_REG_GLOBAL_MONITOR			0x00050
> +
> +#define MALI_C55_REG_GEN_VIDEO				0x00080
> +#define MALI_C55_REG_GEN_VIDEO_ON_MASK			BIT(0)
> +#define MALI_C55_REG_GEN_VIDEO_MULTI_MASK		BIT(1)
> +#define MALI_C55_REG_GEN_PREFETCH_MASK			GENMASK(31, 16)
> +
> +#define MALI_C55_REG_MCU_CONFIG				0x00020
> +#define MALI_C55_REG_MCU_CONFIG_OVERRIDE_MASK		BIT(0)
> +#define MALI_C55_REG_MCU_CONFIG_WRITE_MASK		BIT(1)
> +#define MALI_C55_REG_MCU_CONFIG_WRITE_PING		BIT(1)
> +#define MALI_C55_REG_MCU_CONFIG_WRITE_PONG		0x00
> +#define MALI_C55_REG_MULTI_CONTEXT_MODE_MASK		BIT(8)
> +#define MALI_C55_REG_PING_PONG_READ			0x00024
> +#define MALI_C55_REG_PING_PONG_READ_MASK		BIT(2)
> +
> +#define MALI_C55_REG_INTERRUPT_CLEAR_VECTOR		0x00034
> +#define MALI_C55_REG_INTERRUPT_CLEAR			0x00040
> +#define MALI_C55_REG_INTERRUPT_STATUS_VECTOR		0x00044
> +#define MALI_C55_REG_GLOBAL_PARAMETER_STATUS		0x00068
> +#define MALI_C55_GPS_PONG_FITTED			BIT(0)
> +#define MALI_C55_GPS_WDR_FITTED				BIT(1)
> +#define MALI_C55_GPS_COMPRESSION_FITTED			BIT(2)
> +#define MALI_C55_GPS_TEMPER_FITTED			BIT(3)
> +#define MALI_C55_GPS_SINTER_LITE_FITTED			BIT(4)
> +#define MALI_C55_GPS_SINTER_FITTED			BIT(5)
> +#define MALI_C55_GPS_IRIDIX_LTM_FITTED			BIT(6)
> +#define MALI_C55_GPS_IRIDIX_GTM_FITTED			BIT(7)
> +#define MALI_C55_GPS_CNR_FITTED				BIT(8)
> +#define MALI_C55_GPS_FRSCALER_FITTED			BIT(9)
> +#define MALI_C55_GPS_DS_PIPE_FITTED			BIT(10)
> +
> +#define MALI_C55_REG_BLANKING				0x00084
> +#define MALI_C55_REG_HBLANK_MASK			GENMASK(15, 0)
> +#define MALI_C55_REG_VBLANK_MASK			GENMASK(31, 16)
> +
> +#define MALI_C55_REG_HC_START				0x00088
> +#define MALI_C55_HC_START(h)				(((h) & 0xffff) << 16)
> +#define MALI_C55_REG_HC_SIZE				0x0008c
> +#define MALI_C55_HC_SIZE(h)				((h) & 0xffff)
> +#define MALI_C55_REG_VC_START_SIZE			0x00094
> +#define MALI_C55_VC_START(v)				((v) & 0xffff)
> +#define MALI_C55_VC_SIZE(v)				(((v) & 0xffff) << 16)
> +
> +/* Ping/Pong Configuration Space */
> +#define MALI_C55_REG_BASE_ADDR				0x18e88
> +#define MALI_C55_REG_FR_BYPASS				0x18ec4
> +#define MALI_C55_REG_DS_BYPASS				0x18ec8
> +#define MALI_C55_BYPASS_CROP				BIT(0)
> +#define MALI_C55_BYPASS_SCALER				BIT(1)
> +#define MALI_C55_BYPASS_GAMMA_RGB			BIT(2)
> +#define MALI_C55_BYPASS_SHARPEN				BIT(3)
> +#define MALI_C55_BYPASS_CS_CONV				BIT(4)
> +#define MALI_C55_REG_ISP_RAW_BYPASS			0x18ecc
> +#define MALI_C55_ISP_RAW_BYPASS_BYPASS_MASK		BIT(0)
> +#define MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK		GENMASK(9, 8)
> +#define MALI_C55_ISP_RAW_BYPASS_RAW_FR_BYPASS		2
> +#define MALI_C55_ISP_RAW_BYPASS_RGB_FR_BYPASS		1
> +#define MALI_C55_ISP_RAW_BYPASS_DS_PIPE_DISABLE		BIT(1)
> +#define MALI_C55_ISP_RAW_BYPASS_RAW_BYPASS		BIT(0)
> +
> +#define MALI_C55_REG_ACTIVE_WIDTH_MASK			0xffff
> +#define MALI_C55_REG_ACTIVE_HEIGHT_MASK			0xffff0000
> +#define MALI_C55_REG_BAYER_ORDER			0x18e8c
> +#define MALI_C55_BAYER_ORDER_MASK			GENMASK(1, 0)
> +#define MALI_C55_REG_TPG_CH0				0x18ed8
> +#define MALI_C55_TEST_PATTERN_ON_OFF			BIT(0)
> +#define MALI_C55_TEST_PATTERN_RGB_MASK			BIT(1)
> +#define MALI_C55_REG_TPG_R_BACKGROUND			0x18ee0
> +#define MALI_C55_REG_TPG_G_BACKGROUND			0x18ee4
> +#define MALI_C55_REG_TPG_B_BACKGROUND			0x18ee8
> +#define MALI_C55_TPG_BACKGROUND_MAX			0xfffff
> +#define MALI_C55_REG_INPUT_WIDTH			0x18f98
> +#define MALI_C55_INPUT_WIDTH_MASK			GENMASK(18, 16)
> +#define MALI_C55_INPUT_WIDTH_8BIT			0
> +#define MALI_C55_INPUT_WIDTH_10BIT			1
> +#define MALI_C55_INPUT_WIDTH_12BIT			2
> +#define MALI_C55_INPUT_WIDTH_14BIT			3
> +#define MALI_C55_INPUT_WIDTH_16BIT			4
> +#define MALI_C55_INPUT_WIDTH_20BIT			5
> +#define MALI_C55_REG_SPACE_SIZE				0x4000
> +#define MALI_C55_REG_CONFIG_SPACES_OFFSET		0x0ab6c
> +#define MALI_C55_CONFIG_SPACE_SIZE			0x1231c
> +
> +#define MALI_C55_REG_CS_CONV_CONFIG(offset)		(0x1c098 + (offset))
> +#define MALI_C55_CS_CONV_MATRIX_MASK			BIT(0)
> +#define MALI_C55_CS_CONV_FILTER_MASK			BIT(1)
> +#define MALI_C55_CS_CONV_HORZ_DOWNSAMPLE_MASK		BIT(2)
> +#define MALI_C55_CS_CONV_VERT_DOWNSAMPLE_MASK		BIT(3)
> +#define MALI_C55_REG_Y_WRITER_MODE(offset)		(0x1c0ec + (offset))
> +#define MALI_C55_REG_UV_WRITER_MODE(offset)		(0x1c144 + (offset))
> +#define MALI_C55_WRITER_MODE_MASK			GENMASK(4, 0)
> +#define MALI_C55_WRITER_SUBMODE_MASK			GENMASK(7, 6)
> +#define MALI_C55_WRITER_FRAME_WRITE_MASK		BIT(9)
> +#define MALI_C55_REG_ACTIVE_OUT_Y_SIZE(offset)		(0x1c0f0 + (offset))
> +#define MALI_C55_REG_ACTIVE_OUT_UV_SIZE(offset)		(0x1c148 + (offset))
> +#define MALI_C55_REG_ACTIVE_OUT_SIZE_W(w)		((w) << 0)
> +#define MALI_C55_REG_ACTIVE_OUT_SIZE_H(h)		((h) << 16)
> +#define MALI_C55_REG_Y_WRITER_BANKS_BASE(offset)	(0x1c0f4 + (offset))
> +#define MALI_C55_REG_Y_WRITER_BANKS_CONFIG(offset)	(0x1c108 + (offset))
> +#define MALI_C55_REG_Y_WRITER_MAX_BANKS_MASK		GENMASK(2, 0)
> +#define MALI_C55_REG_Y_WRITER_BANKS_RESTART		BIT(3)
> +#define MALI_C55_REG_Y_WRITER_OFFSET(offset)		(0x1c10c + (offset))
> +#define MALI_C55_REG_UV_WRITER_BANKS_BASE(offset)	(0x1c14c + (offset))
> +#define MALI_C55_REG_UV_WRITER_BANKS_CONFIG(offset)	(0x1c160 + (offset))
> +#define MALI_C55_REG_UV_WRITER_MAX_BANKS_MASK		GENMASK(2, 0)
> +#define MALI_C55_REG_UV_WRITER_BANKS_RESTART		BIT(3)
> +#define MALI_C55_REG_UV_WRITER_OFFSET(offset)		(0x1c164 + (offset))
> +
> +#define MALI_C55_REG_TEST_GEN_CH0_OFF_ON
> +#define MALI_C55_REG_TEST_GEN_CH0_PATTERN_TYPE		0x18edc
> +
> +#define MALI_C55_REG_CROP_EN(offset)			(0x1c028 + (offset))
> +#define MALI_C55_CROP_ENABLE				BIT(0)
> +#define MALI_C55_REG_CROP_X_START(offset)		(0x1c02c + (offset))
> +#define MALI_C55_REG_CROP_Y_START(offset)		(0x1c030 + (offset))
> +#define MALI_C55_REG_CROP_X_SIZE(offset)		(0x1c034 + (offset))
> +#define MALI_C55_REG_CROP_Y_SIZE(offset)		(0x1c038 + (offset))
> +#define MALI_C55_REG_SCALER_TIMEOUT_EN(offset)		(0x1c040 + (offset))
> +#define MALI_C55_SCALER_TIMEOUT_EN			BIT(4)
> +#define MALI_C55_SCALER_TIMEOUT(t)			((t) << 16)
> +#define MALI_C55_REG_SCALER_IN_WIDTH(offset)		(0x1c044 + (offset))
> +#define MALI_C55_REG_SCALER_IN_HEIGHT(offset)		(0x1c048 + (offset))
> +#define MALI_C55_REG_SCALER_OUT_WIDTH(offset)		(0x1c04c + (offset))
> +#define MALI_C55_REG_SCALER_OUT_HEIGHT(offset)		(0x1c050 + (offset))
> +#define MALI_C55_REG_SCALER_HFILT_TINC(offset)		(0x1c054 + (offset))
> +#define MALI_C55_REG_SCALER_HFILT_COEF(offset)		(0x1c058 + (offset))
> +#define MALI_C55_REG_SCALER_VFILT_TINC(offset)		(0x1c05c + (offset))
> +#define MALI_C55_REG_SCALER_VFILT_COEF(offset)		(0x1c060 + (offset))
> +
> +/* Output DMA Writer */
> +
> +#define MALI_C55_OUTPUT_DISABLED		0
> +#define MALI_C55_OUTPUT_RGB32			1
> +#define MALI_C55_OUTPUT_A2R10G10B10		2
> +#define MALI_C55_OUTPUT_RGB565			3
> +#define MALI_C55_OUTPUT_RGB24			4
> +#define MALI_C55_OUTPUT_GEN32			5
> +#define MALI_C55_OUTPUT_RAW16			6
> +#define MALI_C55_OUTPUT_AYUV			8
> +#define MALI_C55_OUTPUT_Y410			9
> +#define MALI_C55_OUTPUT_YUY2			10
> +#define MALI_C55_OUTPUT_UYVY			11
> +#define MALI_C55_OUTPUT_Y210			12
> +#define MALI_C55_OUTPUT_NV12_21			13
> +#define MALI_C55_OUTPUT_YUV_420_422		17
> +#define MALI_C55_OUTPUT_P210_P010		19
> +#define MALI_C55_OUTPUT_YUV422			20
> +
> +#define MALI_C55_OUTPUT_PLANE_ALT0		0
> +#define MALI_C55_OUTPUT_PLANE_ALT1		1
> +#define MALI_C55_OUTPUT_PLANE_ALT2		2
> +
> +#endif /* _MALI_C55_REGISTERS_H */
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h b/drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h
> new file mode 100644
> index 000000000000..eea473c36922
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h
> @@ -0,0 +1,382 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * ARM Mali-C55 ISP Driver - Resizer Coefficients
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#ifndef _MALI_C55_RESIZER_COEFS_H
> +#define _MALI_C55_RESIZER_COEFS_H
> +
> +#include "mali-c55-common.h"
> +
> +#define MALI_C55_RESIZER_COEFS_NUM_BANKS	8
> +#define MALI_C55_RESIZER_COEFS_NUM_ENTRIES	64
> +
> +static const unsigned int mali_c55_scaler_h_filter_coefficients[8][64] = {
> +	{	/* Bank 0 */
> +		0x24fc0000, 0x0000fc24, 0x27fc0000, 0x0000fc21,
> +		0x28fc0000, 0x0000fd1f, 0x2cfb0000, 0x0000fd1c,
> +		0x2efb0000, 0x0000fd1a, 0x30fb0000, 0x0000fe17,
> +		0x32fb0000, 0x0000fe15, 0x35fb0000, 0x0000fe12,
> +		0x35fc0000, 0x0000ff10, 0x37fc0000, 0x0000ff0e,
> +		0x39fc0000, 0x0000ff0c, 0x3afd0000, 0x0000ff0a,
> +		0x3afe0000, 0x00000008, 0x3cfe0000, 0x00000006,
> +		0x3dff0000, 0x00000004, 0x3d000000, 0x00000003,
> +		0x3c020000, 0x00000002, 0x3d030000, 0x00000000,
> +		0x3d040000, 0x000000ff, 0x3c060000, 0x000000fe,
> +		0x3a080000, 0x000000fe, 0x3a0aff00, 0x000000fd,
> +		0x390cff00, 0x000000fc, 0x370eff00, 0x000000fc,
> +		0x3510ff00, 0x000000fc, 0x3512fe00, 0x000000fb,
> +		0x3215fe00, 0x000000fb, 0x3017fe00, 0x000000fb,
> +		0x2e1afd00, 0x000000fb, 0x2c1cfd00, 0x000000fb,
> +		0x281ffd00, 0x000000fc, 0x2721fc00, 0x000000fc,
> +	},
> +	{	/* Bank 1 */
> +		0x25fb0000, 0x0000fb25, 0x27fb0000, 0x0000fb23,
> +		0x29fb0000, 0x0000fb21, 0x2afc0000, 0x0000fb1f,
> +		0x2cfc0000, 0x0000fb1d, 0x2efc0000, 0x0000fb1b,
> +		0x2ffd0000, 0x0000fb19, 0x2ffe0000, 0x0000fc17,
> +		0x31fe0000, 0x0000fc15, 0x32ff0000, 0x0000fc13,
> +		0x3400ff00, 0x0000fc11, 0x3301ff00, 0x0000fd10,
> +		0x3402ff00, 0x0000fd0e, 0x3503ff00, 0x0000fd0c,
> +		0x3505ff00, 0x0000fd0a, 0x3506fe00, 0x0000fe09,
> +		0x3607fe00, 0x0000fe07, 0x3509fe00, 0x0000fe06,
> +		0x350afd00, 0x0000ff05, 0x350cfd00, 0x0000ff03,
> +		0x340efd00, 0x0000ff02, 0x3310fd00, 0x0000ff01,
> +		0x3411fc00, 0x0000ff00, 0x3213fc00, 0x000000ff,
> +		0x3115fc00, 0x000000fe, 0x2f17fc00, 0x000000fe,
> +		0x2f19fb00, 0x000000fd, 0x2e1bfb00, 0x000000fc,
> +		0x2c1dfb00, 0x000000fc, 0x2a1ffb00, 0x000000fc,
> +		0x2921fb00, 0x000000fb, 0x2723fb00, 0x000000fb,
> +	},
> +	{	/* Bank 2 */
> +		0x1f010000, 0x0000011f, 0x21010000, 0x0000001e,
> +		0x21020000, 0x0000001d, 0x22020000, 0x0000001c,
> +		0x23030000, 0x0000ff1b, 0x2404ff00, 0x0000ff1a,
> +		0x2504ff00, 0x0000ff19, 0x2505ff00, 0x0000ff18,
> +		0x2606ff00, 0x0000fe17, 0x2607ff00, 0x0000fe16,
> +		0x2708ff00, 0x0000fe14, 0x2709ff00, 0x0000fe13,
> +		0x270aff00, 0x0000fe12, 0x280bfe00, 0x0000fe11,
> +		0x280cfe00, 0x0000fe10, 0x280dfe00, 0x0000fe0f,
> +		0x280efe00, 0x0000fe0e, 0x280ffe00, 0x0000fe0d,
> +		0x2810fe00, 0x0000fe0c, 0x2811fe00, 0x0000fe0b,
> +		0x2712fe00, 0x0000ff0a, 0x2713fe00, 0x0000ff09,
> +		0x2714fe00, 0x0000ff08, 0x2616fe00, 0x0000ff07,
> +		0x2617fe00, 0x0000ff06, 0x2518ff00, 0x0000ff05,
> +		0x2519ff00, 0x0000ff04, 0x241aff00, 0x0000ff04,
> +		0x231bff00, 0x00000003, 0x221c0000, 0x00000002,
> +		0x211d0000, 0x00000002, 0x211e0000, 0x00000001,
> +	},
> +	{	/* Bank 3 */
> +		0x1b06ff00, 0x00ff061b, 0x1b07ff00, 0x00ff061a,
> +		0x1c07ff00, 0x00ff051a, 0x1c08ff00, 0x00ff0519,
> +		0x1c09ff00, 0x00ff0419, 0x1d09ff00, 0x00ff0418,
> +		0x1e0aff00, 0x00ff0317, 0x1e0aff00, 0x00ff0317,
> +		0x1e0bff00, 0x00ff0316, 0x1f0cff00, 0x00ff0215,
> +		0x1e0cff00, 0x00000215, 0x1e0dff00, 0x00000214,
> +		0x1e0e0000, 0x00000113, 0x1e0e0000, 0x00000113,
> +		0x1e0f0000, 0x00000112, 0x1f100000, 0x00000011,
> +		0x20100000, 0x00000010, 0x1f110000, 0x00000010,
> +		0x1e120100, 0x0000000f, 0x1e130100, 0x0000000e,
> +		0x1e130100, 0x0000000e, 0x1e140200, 0x0000ff0d,
> +		0x1e150200, 0x0000ff0c, 0x1f1502ff, 0x0000ff0c,
> +		0x1e1603ff, 0x0000ff0b, 0x1e1703ff, 0x0000ff0a,
> +		0x1e1703ff, 0x0000ff0a, 0x1d1804ff, 0x0000ff09,
> +		0x1c1904ff, 0x0000ff09, 0x1c1905ff, 0x0000ff08,
> +		0x1c1a05ff, 0x0000ff07, 0x1b1a06ff, 0x0000ff07,
> +	},
> +	{	/* Bank 4 */
> +		0x17090000, 0x00000917, 0x18090000, 0x00000916,
> +		0x170a0100, 0x00000816, 0x170a0100, 0x00000816,
> +		0x180b0100, 0x00000715, 0x180b0100, 0x00000715,
> +		0x170c0100, 0x00000715, 0x190c0100, 0x00000614,
> +		0x180d0100, 0x00000614, 0x190d0200, 0x00000513,
> +		0x180e0200, 0x00000513, 0x180e0200, 0x00000513,
> +		0x1a0e0200, 0x00000412, 0x190f0200, 0x00000412,
> +		0x190f0300, 0x00000411, 0x18100300, 0x00000411,
> +		0x1a100300, 0x00000310, 0x18110400, 0x00000310,
> +		0x19110400, 0x0000030f, 0x19120400, 0x0000020f,
> +		0x1a120400, 0x0000020e, 0x18130500, 0x0000020e,
> +		0x18130500, 0x0000020e, 0x19130500, 0x0000020d,
> +		0x18140600, 0x0000010d, 0x19140600, 0x0000010c,
> +		0x17150700, 0x0000010c, 0x18150700, 0x0000010b,
> +		0x18150700, 0x0000010b, 0x17160800, 0x0000010a,
> +		0x17160800, 0x0000010a, 0x18160900, 0x00000009,
> +	},
> +	{	/* Bank 5 */
> +		0x120b0300, 0x00030b12, 0x120c0300, 0x00030b11,
> +		0x110c0400, 0x00030b11, 0x110c0400, 0x00030b11,
> +		0x130c0400, 0x00020a11, 0x120d0400, 0x00020a11,
> +		0x110d0500, 0x00020a11, 0x110d0500, 0x00020a11,
> +		0x130d0500, 0x00010911, 0x130e0500, 0x00010910,
> +		0x120e0600, 0x00010910, 0x120e0600, 0x00010910,
> +		0x130e0600, 0x00010810, 0x120f0600, 0x00010810,
> +		0x120f0700, 0x00000810, 0x130f0700, 0x0000080f,
> +		0x140f0700, 0x0000070f, 0x130f0800, 0x0000070f,
> +		0x12100800, 0x0000070f, 0x12100801, 0x0000060f,
> +		0x13100801, 0x0000060e, 0x12100901, 0x0000060e,
> +		0x12100901, 0x0000060e, 0x13100901, 0x0000050e,
> +		0x13110901, 0x0000050d, 0x11110a02, 0x0000050d,
> +		0x11110a02, 0x0000050d, 0x12110a02, 0x0000040d,
> +		0x13110a02, 0x0000040c, 0x11110b03, 0x0000040c,
> +		0x11110b03, 0x0000040c, 0x12110b03, 0x0000030c,
> +	},
> +	{	/* Bank 6 */
> +		0x0b0a0805, 0x00080a0c, 0x0b0a0805, 0x00080a0c,
> +		0x0c0a0805, 0x00080a0b, 0x0c0a0805, 0x00080a0b,
> +		0x0d0a0805, 0x00070a0b, 0x0d0a0805, 0x00070a0b,
> +		0x0d0a0805, 0x00070a0b, 0x0c0a0806, 0x00070a0b,
> +		0x0b0b0806, 0x00070a0b, 0x0c0b0806, 0x0007090b,
> +		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
> +		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
> +		0x0b0b0906, 0x0007090b, 0x0c0b0906, 0x0006090b,
> +		0x0c0b0906, 0x0006090b, 0x0c0b0906, 0x0006090b,
> +		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
> +		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
> +		0x0b0b0907, 0x0006090b, 0x0c0b0907, 0x0006080b,
> +		0x0b0b0a07, 0x0006080b, 0x0c0b0a07, 0x0006080a,
> +		0x0d0b0a07, 0x0005080a, 0x0d0b0a07, 0x0005080a,
> +		0x0d0b0a07, 0x0005080a, 0x0c0b0a08, 0x0005080a,
> +		0x0c0b0a08, 0x0005080a, 0x0c0b0a08, 0x0005080a,
> +	},
> +	{	/* Bank 7 */
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
> +	}
> +};
> +
> +static const unsigned int mali_c55_scaler_v_filter_coefficients[8][64] = {
> +	{	/* Bank 0 */
> +		0x2424fc00, 0x000000fc, 0x2721fc00, 0x000000fc,
> +		0x281ffd00, 0x000000fc, 0x2c1cfd00, 0x000000fb,
> +		0x2e1afd00, 0x000000fb, 0x3017fe00, 0x000000fb,
> +		0x3215fe00, 0x000000fb, 0x3512fe00, 0x000000fb,
> +		0x3510ff00, 0x000000fc, 0x370eff00, 0x000000fc,
> +		0x390cff00, 0x000000fc, 0x3a0aff00, 0x000000fd,
> +		0x3a080000, 0x000000fe, 0x3c060000, 0x000000fe,
> +		0x3d040000, 0x000000ff, 0x3d030000, 0x00000000,
> +		0x3c020000, 0x00000002, 0x3d000000, 0x00000003,
> +		0x3dff0000, 0x00000004, 0x3cfe0000, 0x00000006,
> +		0x3afe0000, 0x00000008, 0x3afd0000, 0x0000ff0a,
> +		0x39fc0000, 0x0000ff0c, 0x37fc0000, 0x0000ff0e,
> +		0x35fc0000, 0x0000ff10, 0x35fb0000, 0x0000fe12,
> +		0x32fb0000, 0x0000fe15, 0x30fb0000, 0x0000fe17,
> +		0x2efb0000, 0x0000fd1a, 0x2cfb0000, 0x0000fd1c,
> +		0x28fc0000, 0x0000fd1f, 0x27fc0000, 0x0000fc21,
> +	},
> +	{	/* Bank 1 */
> +		0x2525fb00, 0x000000fb, 0x2723fb00, 0x000000fb,
> +		0x2921fb00, 0x000000fb, 0x2a1ffb00, 0x000000fc,
> +		0x2c1dfb00, 0x000000fc, 0x2e1bfb00, 0x000000fc,
> +		0x2f19fb00, 0x000000fd, 0x2f17fc00, 0x000000fe,
> +		0x3115fc00, 0x000000fe, 0x3213fc00, 0x000000ff,
> +		0x3411fc00, 0x0000ff00, 0x3310fd00, 0x0000ff01,
> +		0x340efd00, 0x0000ff02, 0x350cfd00, 0x0000ff03,
> +		0x350afd00, 0x0000ff05, 0x3509fe00, 0x0000fe06,
> +		0x3607fe00, 0x0000fe07, 0x3506fe00, 0x0000fe09,
> +		0x3505ff00, 0x0000fd0a, 0x3503ff00, 0x0000fd0c,
> +		0x3402ff00, 0x0000fd0e, 0x3301ff00, 0x0000fd10,
> +		0x3400ff00, 0x0000fc11, 0x32ff0000, 0x0000fc13,
> +		0x31fe0000, 0x0000fc15, 0x2ffe0000, 0x0000fc17,
> +		0x2ffd0000, 0x0000fb19, 0x2efc0000, 0x0000fb1b,
> +		0x2cfc0000, 0x0000fb1d, 0x2afc0000, 0x0000fb1f,
> +		0x29fb0000, 0x0000fb21, 0x27fb0000, 0x0000fb23,
> +	},
> +	{	/* Bank 2 */
> +		0x1f1f0100, 0x00000001, 0x211e0000, 0x00000001,
> +		0x211d0000, 0x00000002, 0x221c0000, 0x00000002,
> +		0x231bff00, 0x00000003, 0x241aff00, 0x0000ff04,
> +		0x2519ff00, 0x0000ff04, 0x2518ff00, 0x0000ff05,
> +		0x2617fe00, 0x0000ff06, 0x2616fe00, 0x0000ff07,
> +		0x2714fe00, 0x0000ff08, 0x2713fe00, 0x0000ff09,
> +		0x2712fe00, 0x0000ff0a, 0x2811fe00, 0x0000fe0b,
> +		0x2810fe00, 0x0000fe0c, 0x280ffe00, 0x0000fe0d,
> +		0x280efe00, 0x0000fe0e, 0x280dfe00, 0x0000fe0f,
> +		0x280cfe00, 0x0000fe10, 0x280bfe00, 0x0000fe11,
> +		0x270aff00, 0x0000fe12, 0x2709ff00, 0x0000fe13,
> +		0x2708ff00, 0x0000fe14, 0x2607ff00, 0x0000fe16,
> +		0x2606ff00, 0x0000fe17, 0x2505ff00, 0x0000ff18,
> +		0x2504ff00, 0x0000ff19, 0x2404ff00, 0x0000ff1a,
> +		0x23030000, 0x0000ff1b, 0x22020000, 0x0000001c,
> +		0x21020000, 0x0000001d, 0x21010000, 0x0000001e,
> +	},
> +	{	/* Bank 3 */
> +		0x1b1b06ff, 0x0000ff06, 0x1b1a06ff, 0x0000ff07,
> +		0x1c1a05ff, 0x0000ff07, 0x1c1905ff, 0x0000ff08,
> +		0x1c1904ff, 0x0000ff09, 0x1d1804ff, 0x0000ff09,
> +		0x1e1703ff, 0x0000ff0a, 0x1e1703ff, 0x0000ff0a,
> +		0x1e1603ff, 0x0000ff0b, 0x1f1502ff, 0x0000ff0c,
> +		0x1e150200, 0x0000ff0c, 0x1e140200, 0x0000ff0d,
> +		0x1e130100, 0x0000000e, 0x1e130100, 0x0000000e,
> +		0x1e120100, 0x0000000f, 0x1f110000, 0x00000010,
> +		0x20100000, 0x00000010, 0x1f100000, 0x00000011,
> +		0x1e0f0000, 0x00000112, 0x1e0e0000, 0x00000113,
> +		0x1e0e0000, 0x00000113, 0x1e0dff00, 0x00000214,
> +		0x1e0cff00, 0x00000215, 0x1f0cff00, 0x00ff0215,
> +		0x1e0bff00, 0x00ff0316, 0x1e0aff00, 0x00ff0317,
> +		0x1e0aff00, 0x00ff0317, 0x1d09ff00, 0x00ff0418,
> +		0x1c09ff00, 0x00ff0419, 0x1c08ff00, 0x00ff0519,
> +		0x1c07ff00, 0x00ff051a, 0x1b07ff00, 0x00ff061a,
> +	},
> +	{	/* Bank 4 */
> +		0x17170900, 0x00000009, 0x18160900, 0x00000009,
> +		0x17160800, 0x0000010a, 0x17160800, 0x0000010a,
> +		0x18150700, 0x0000010b, 0x18150700, 0x0000010b,
> +		0x17150700, 0x0000010c, 0x19140600, 0x0000010c,
> +		0x18140600, 0x0000010d, 0x19130500, 0x0000020d,
> +		0x18130500, 0x0000020e, 0x18130500, 0x0000020e,
> +		0x1a120400, 0x0000020e, 0x19120400, 0x0000020f,
> +		0x19110400, 0x0000030f, 0x18110400, 0x00000310,
> +		0x1a100300, 0x00000310, 0x18100300, 0x00000411,
> +		0x190f0300, 0x00000411, 0x190f0200, 0x00000412,
> +		0x1a0e0200, 0x00000412, 0x180e0200, 0x00000513,
> +		0x180e0200, 0x00000513, 0x190d0200, 0x00000513,
> +		0x180d0100, 0x00000614, 0x190c0100, 0x00000614,
> +		0x170c0100, 0x00000715, 0x180b0100, 0x00000715,
> +		0x180b0100, 0x00000715, 0x170a0100, 0x00000816,
> +		0x170a0100, 0x00000816, 0x18090000, 0x00000916,
> +	},
> +	{	/* Bank 5 */
> +		0x12120b03, 0x0000030b, 0x12110b03, 0x0000030c,
> +		0x11110b03, 0x0000040c, 0x11110b03, 0x0000040c,
> +		0x13110a02, 0x0000040c, 0x12110a02, 0x0000040d,
> +		0x11110a02, 0x0000050d, 0x11110a02, 0x0000050d,
> +		0x13110901, 0x0000050d, 0x13100901, 0x0000050e,
> +		0x12100901, 0x0000060e, 0x12100901, 0x0000060e,
> +		0x13100801, 0x0000060e, 0x12100801, 0x0000060f,
> +		0x12100800, 0x0000070f, 0x130f0800, 0x0000070f,
> +		0x140f0700, 0x0000070f, 0x130f0700, 0x0000080f,
> +		0x120f0700, 0x00000810, 0x120f0600, 0x00010810,
> +		0x130e0600, 0x00010810, 0x120e0600, 0x00010910,
> +		0x120e0600, 0x00010910, 0x130e0500, 0x00010910,
> +		0x130d0500, 0x00010911, 0x110d0500, 0x00020a11,
> +		0x110d0500, 0x00020a11, 0x120d0400, 0x00020a11,
> +		0x130c0400, 0x00020a11, 0x110c0400, 0x00030b11,
> +		0x110c0400, 0x00030b11, 0x120c0300, 0x00030b11,
> +	},
> +	{	/* Bank 6 */
> +		0x0b0c0a08, 0x0005080a, 0x0b0c0a08, 0x0005080a,
> +		0x0c0b0a08, 0x0005080a, 0x0c0b0a08, 0x0005080a,
> +		0x0d0b0a07, 0x0005080a, 0x0d0b0a07, 0x0005080a,
> +		0x0d0b0a07, 0x0005080a, 0x0c0b0a07, 0x0006080a,
> +		0x0b0b0a07, 0x0006080b, 0x0c0b0907, 0x0006080b,
> +		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
> +		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
> +		0x0b0b0907, 0x0006090b, 0x0c0b0906, 0x0006090b,
> +		0x0c0b0906, 0x0006090b, 0x0c0b0906, 0x0006090b,
> +		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
> +		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
> +		0x0b0b0906, 0x0007090b, 0x0c0b0806, 0x0007090b,
> +		0x0b0b0806, 0x00070a0b, 0x0c0a0806, 0x00070a0b,
> +		0x0d0a0805, 0x00070a0b, 0x0d0a0805, 0x00070a0b,
> +		0x0d0a0805, 0x00070a0b, 0x0c0a0805, 0x00080a0b,
> +		0x0c0a0805, 0x00080a0b, 0x0c0a0805, 0x00080a0b,
> +	},
> +	{	/* Bank 7 */
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
> +	}
> +};
> +
> +struct mali_c55_resizer_coef_bank {
> +	unsigned int bank;
> +	unsigned int top;
> +	unsigned int bottom;
> +};
> +
> +static const struct mali_c55_resizer_coef_bank mali_c55_coefficient_banks[] = {
> +	{
> +		.bank = 0,
> +		.top = 1000,
> +		.bottom = 770,
> +	},
> +	{
> +		.bank = 1,
> +		.top = 769,
> +		.bottom = 600,
> +	},
> +	{
> +		.bank = 2,
> +		.top = 599,
> +		.bottom = 460,
> +	},
> +	{
> +		.bank = 3,
> +		.top = 459,
> +		.bottom = 354,
> +	},
> +	{
> +		.bank = 4,
> +		.top = 353,
> +		.bottom = 273,
> +	},
> +	{
> +		.bank = 5,
> +		.top = 272,
> +		.bottom = 210,
> +	},
> +	{
> +		.bank = 6,
> +		.top = 209,
> +		.bottom = 162,
> +	},
> +	{
> +		.bank = 7,
> +		.top = 161,
> +		.bottom = 125,
> +	},
> +};
> +
> +static unsigned int mali_c55_calculate_bank_num(struct mali_c55 *mali_c55,
> +						unsigned int crop,
> +						unsigned int scale)
> +{
> +	unsigned int tmp;
> +	unsigned int i;
> +
> +	tmp = (scale * 1000) / crop;

This looks like something that can overflow. Can it?

> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55_coefficient_banks); i++) {
> +		if (tmp >= mali_c55_coefficient_banks[i].bottom &&
> +		    tmp <= mali_c55_coefficient_banks[i].top)
> +			return mali_c55_coefficient_banks[i].bank;
> +	}
> +
> +	/*
> +	 * We shouldn't ever get here, in theory. As we have no good choices
> +	 * simply warn the user and use the first bank of coefficients.
> +	 */
> +	dev_warn(mali_c55->dev, "scaling factor outside defined bounds\n");
> +	return 0;
> +}
> +
> +#endif /* _MALI_C55_RESIZER_COEFS_H */
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c b/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
> new file mode 100644
> index 000000000000..8e0669a5f391
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
> @@ -0,0 +1,740 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ARM Mali-C55 ISP Driver - Image signal processor
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#include <linux/math.h>
> +#include <linux/minmax.h>
> +
> +#include <media/media-entity.h>
> +#include <media/v4l2-subdev.h>
> +
> +#include "mali-c55-common.h"
> +#include "mali-c55-registers.h"
> +#include "mali-c55-resizer-coefs.h"
> +
> +/* Scaling factor in Q4.20 format. */
> +#define MALI_C55_RZR_SCALER_FACTOR	1048576

(1U << 20)

?

> +
> +static const u32 rzr_non_bypass_src_fmts[] = {
> +	MEDIA_BUS_FMT_RGB121212_1X36,
> +	MEDIA_BUS_FMT_YUV10_1X30
> +};
> +
> +static const char * const mali_c55_resizer_names[] = {
> +	[MALI_C55_RZR_FR] = "resizer fr",
> +	[MALI_C55_RZR_DS] = "resizer ds",
> +};
> +
> +static int mali_c55_rzr_program_crop(struct mali_c55_resizer *rzr,
> +				     struct v4l2_subdev_state *state)
> +{
> +	unsigned int reg_offset = rzr->cap_dev->reg_offset;
> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
> +	struct v4l2_mbus_framefmt *fmt;
> +	struct v4l2_rect *crop;
> +
> +	/* Verify if crop should be enabled. */
> +	fmt = v4l2_subdev_state_get_format(state, MALI_C55_RZR_SINK_PAD, 0);
> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD, 0);
> +
> +	if (fmt->width == crop->width && fmt->height == crop->height)
> +		return MALI_C55_BYPASS_CROP;
> +
> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_X_START(reg_offset),
> +		       crop->left);
> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_Y_START(reg_offset),
> +		       crop->top);
> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_X_SIZE(reg_offset),
> +		       crop->width);
> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_Y_SIZE(reg_offset),
> +		       crop->height);
> +
> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_EN(reg_offset),
> +		       MALI_C55_CROP_ENABLE);
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_program_resizer(struct mali_c55_resizer *rzr,
> +					struct v4l2_subdev_state *state)
> +{
> +	unsigned int reg_offset = rzr->cap_dev->reg_offset;
> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
> +	struct v4l2_rect *crop, *scale;
> +	unsigned int h_bank, v_bank;
> +	u64 h_scale, v_scale;
> +
> +	/* Verify if scaling should be enabled. */
> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD, 0);
> +	scale = v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD, 0);
> +
> +	if (crop->width == scale->width && crop->height == scale->height)
> +		return MALI_C55_BYPASS_SCALER;
> +
> +	/* Program the V/H scaling factor in Q4.20 format. */
> +	h_scale = crop->width * MALI_C55_RZR_SCALER_FACTOR;
> +	v_scale = crop->height * MALI_C55_RZR_SCALER_FACTOR;
> +
> +	do_div(h_scale, scale->width);
> +	do_div(v_scale, scale->height);
> +
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_IN_WIDTH(reg_offset),
> +		       crop->width);
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_IN_HEIGHT(reg_offset),
> +		       crop->height);
> +
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_OUT_WIDTH(reg_offset),
> +		       scale->width);
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_OUT_HEIGHT(reg_offset),
> +		       scale->height);
> +
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_HFILT_TINC(reg_offset),
> +		       h_scale);
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_VFILT_TINC(reg_offset),
> +		       v_scale);
> +
> +	h_bank = mali_c55_calculate_bank_num(mali_c55, crop->width,
> +					     scale->width);
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_HFILT_COEF(reg_offset),
> +		       h_bank);
> +
> +	v_bank = mali_c55_calculate_bank_num(mali_c55, crop->height,
> +					     scale->height);
> +	mali_c55_write(mali_c55,
> +		       MALI_C55_REG_SCALER_VFILT_COEF(reg_offset),
> +		       v_bank);
> +
> +	return 0;
> +}
> +
> +static void mali_c55_rzr_program(struct mali_c55_resizer *rzr,
> +				 struct v4l2_subdev_state *state)
> +{
> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
> +	u32 bypass = 0;
> +
> +	/* Verify if cropping and scaling should be enabled. */
> +	bypass |= mali_c55_rzr_program_crop(rzr, state);
> +	bypass |= mali_c55_rzr_program_resizer(rzr, state);
> +
> +	mali_c55_update_bits(mali_c55, rzr->id == MALI_C55_RZR_FR ?
> +			     MALI_C55_REG_FR_BYPASS : MALI_C55_REG_DS_BYPASS,
> +			     MALI_C55_BYPASS_CROP | MALI_C55_BYPASS_SCALER,
> +			     bypass);
> +}
> +
> +/*
> + * Inspect the routing table to know which of the two (mutually exclusive)
> + * routes is enabled and return the sink pad id of the active route.
> + */
> +static unsigned int mali_c55_rzr_get_active_sink(struct v4l2_subdev_state *state)
> +{
> +	struct v4l2_subdev_krouting *routing = &state->routing;
> +	struct v4l2_subdev_route *route;
> +
> +	/* A single route is enabled at a time. */
> +	for_each_active_route(routing, route)
> +		return route->sink_pad;
> +
> +	return MALI_C55_RZR_SINK_PAD;
> +}
> +
> +static int __mali_c55_rzr_set_routing(struct v4l2_subdev *sd,
> +				      struct v4l2_subdev_state *state,
> +				      struct v4l2_subdev_krouting *routing)
> +{
> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
> +						    sd);
> +	unsigned int active_sink = UINT_MAX;
> +	struct v4l2_rect *crop, *compose;
> +	struct v4l2_subdev_route *route;
> +	unsigned int active_routes = 0;
> +	struct v4l2_mbus_framefmt *fmt;
> +	int ret;
> +
> +	ret = v4l2_subdev_routing_validate(sd, routing, 0);
> +	if (ret)
> +		return ret;
> +
> +	/* Only a single route can be enabled at a time. */
> +	for_each_active_route(routing, route) {
> +		if (++active_routes > 1) {
> +			dev_err(rzr->mali_c55->dev,
> +				"Only one route can be active");
> +			return -EINVAL;
> +		}
> +
> +		active_sink = route->sink_pad;
> +	}
> +	if (active_sink == UINT_MAX) {
> +		dev_err(rzr->mali_c55->dev, "One route has to be active");
> +		return -EINVAL;
> +	}
> +
> +	ret = v4l2_subdev_set_routing(sd, state, routing);
> +	if (ret) {
> +		dev_err(rzr->mali_c55->dev, "Failed to set routing\n");
> +		return ret;
> +	}
> +
> +	fmt = v4l2_subdev_state_get_format(state, active_sink, 0);
> +	crop = v4l2_subdev_state_get_crop(state, active_sink, 0);
> +	compose = v4l2_subdev_state_get_compose(state, active_sink, 0);
> +
> +	fmt->width = MALI_C55_DEFAULT_WIDTH;
> +	fmt->height = MALI_C55_DEFAULT_HEIGHT;
> +	fmt->colorspace = V4L2_COLORSPACE_SRGB;
> +	fmt->field = V4L2_FIELD_NONE;
> +
> +	if (active_sink == MALI_C55_RZR_SINK_PAD) {
> +		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +
> +		crop->left = crop->top = 0;
> +		crop->width = MALI_C55_DEFAULT_WIDTH;
> +		crop->height = MALI_C55_DEFAULT_HEIGHT;
> +
> +		*compose = *crop;
> +	} else {
> +		fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
> +	}
> +
> +	/* Propagate the format to the source pad */
> +	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD, 0) = *fmt;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_enum_mbus_code(struct v4l2_subdev *sd,
> +				       struct v4l2_subdev_state *state,
> +				       struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	struct v4l2_mbus_framefmt *sink_fmt;
> +	const struct mali_c55_isp_fmt *fmt;
> +	unsigned int index = 0;
> +	u32 sink_pad;
> +
> +	switch (code->pad) {
> +	case MALI_C55_RZR_SINK_PAD:
> +		if (code->index)
> +			return -EINVAL;
> +
> +		code->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +
> +		return 0;
> +	case MALI_C55_RZR_SOURCE_PAD:
> +		sink_pad = mali_c55_rzr_get_active_sink(state);
> +		sink_fmt = v4l2_subdev_state_get_format(state, sink_pad, 0);
> +
> +		/*
> +		 * If the active route is from the Bypass sink pad, then the
> +		 * source pad is a simple passthrough of the sink format.
> +		 */
> +
> +		if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
> +			if (code->index)
> +				return -EINVAL;
> +
> +			code->code = sink_fmt->code;
> +			return 0;
> +		}
> +
> +		/*
> +		 * If the active route is from the non-bypass sink then we can
> +		 * select either RGB or conversion to YUV.
> +		 */
> +
> +		if (code->index >= ARRAY_SIZE(rzr_non_bypass_src_fmts))
> +			return -EINVAL;
> +
> +		code->code = rzr_non_bypass_src_fmts[code->index];
> +
> +		return 0;
> +	case MALI_C55_RZR_SINK_BYPASS_PAD:
> +		for_each_mali_isp_fmt(fmt) {
> +			if (index++ == code->index) {
> +				code->code = fmt->code;
> +				return 0;
> +			}
> +		}
> +
> +		break;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int mali_c55_rzr_enum_frame_size(struct v4l2_subdev *sd,
> +					struct v4l2_subdev_state *state,
> +					struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	if (fse->index)
> +		return -EINVAL;
> +
> +	fse->max_width = MALI_C55_MAX_WIDTH;
> +	fse->max_height = MALI_C55_MAX_HEIGHT;
> +	fse->min_width = MALI_C55_MIN_WIDTH;
> +	fse->min_height = MALI_C55_MIN_HEIGHT;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_set_sink_fmt(struct v4l2_subdev *sd,
> +				     struct v4l2_subdev_state *state,
> +				     struct v4l2_subdev_format *format)
> +{
> +	struct v4l2_mbus_framefmt *fmt = &format->format;
> +	struct v4l2_rect *rect;
> +	unsigned int sink_pad;
> +
> +	/*
> +	 * Clamp to min/max and then reset crop and compose rectangles to the
> +	 * newly applied size.
> +	 */
> +	clamp_t(unsigned int, fmt->width,
> +		MALI_C55_MIN_WIDTH, MALI_C55_MAX_WIDTH);
> +	clamp_t(unsigned int, fmt->height,
> +		MALI_C55_MIN_HEIGHT, MALI_C55_MAX_HEIGHT);
> +
> +	sink_pad = mali_c55_rzr_get_active_sink(state);
> +	if (sink_pad == MALI_C55_RZR_SINK_PAD) {
> +		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +
> +		rect = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD);
> +		rect->left = 0;
> +		rect->top = 0;
> +		rect->width = fmt->width;
> +		rect->height = fmt->height;
> +
> +		rect = v4l2_subdev_state_get_compose(state,
> +						     MALI_C55_RZR_SINK_PAD);
> +		rect->left = 0;
> +		rect->top = 0;
> +		rect->width = fmt->width;
> +		rect->height = fmt->height;
> +	} else {
> +		/*
> +		 * Make sure the media bus code is one of the supported
> +		 * ISP input media bus codes.
> +		 */
> +		if (!mali_c55_isp_is_format_supported(fmt->code))
> +			fmt->code = MALI_C55_DEFAULT_MEDIA_BUS_FMT;
> +	}
> +
> +	*v4l2_subdev_state_get_format(state, sink_pad, 0) = *fmt;
> +	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD, 0) = *fmt;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_set_source_fmt(struct v4l2_subdev *sd,
> +				       struct v4l2_subdev_state *state,
> +				       struct v4l2_subdev_format *format)
> +{
> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
> +						    sd);
> +	struct v4l2_mbus_framefmt *fmt = &format->format;
> +	struct v4l2_mbus_framefmt *sink_fmt;
> +	struct v4l2_rect *crop, *compose;
> +	unsigned int sink_pad;
> +	unsigned int i;
> +
> +	sink_pad = mali_c55_rzr_get_active_sink(state);
> +	sink_fmt = v4l2_subdev_state_get_format(state, sink_pad, 0);
> +	crop = v4l2_subdev_state_get_crop(state, sink_pad, 0);
> +	compose = v4l2_subdev_state_get_compose(state, sink_pad, 0);
> +
> +	/* FR Bypass pipe. */
> +
> +	if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
> +		/*
> +		 * Format on the source pad is the same as the one on the
> +		 * sink pad.
> +		 */
> +		fmt->code = sink_fmt->code;
> +
> +		/* RAW bypass disables scaling and cropping. */
> +		crop->top = compose->top = 0;
> +		crop->left = compose->left = 0;
> +		fmt->width = crop->width = compose->width = sink_fmt->width;
> +		fmt->height = crop->height = compose->height = sink_fmt->height;
> +
> +		*v4l2_subdev_state_get_format(state,
> +					      MALI_C55_RZR_SOURCE_PAD) = *fmt;
> +
> +		return 0;
> +	}
> +
> +	/* Regular processing pipe. */
> +
> +	for (i = 0; i < ARRAY_SIZE(rzr_non_bypass_src_fmts); i++) {
> +		if (fmt->code == rzr_non_bypass_src_fmts[i])
> +			break;
> +	}
> +
> +	if (i == ARRAY_SIZE(rzr_non_bypass_src_fmts)) {
> +		dev_dbg(rzr->mali_c55->dev,
> +			"Unsupported mbus code 0x%x: using default\n",
> +			fmt->code);
> +		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
> +	}
> +
> +	/*
> +	 * The source pad format size comes directly from the sink pad
> +	 * compose rectangle.
> +	 */
> +	fmt->width = compose->width;
> +	fmt->height = compose->height;
> +
> +	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD) = *fmt;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_set_fmt(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *state,
> +				struct v4l2_subdev_format *format)
> +{
> +	/*
> +	 * On sink pads fmt is either fixed for the 'regular' processing
> +	 * pad or a RAW format or 20-bit wide RGB/YUV format for the FR bypass
> +	 * pad.
> +	 *
> +	 * On source pad sizes are the result of crop+compose on the sink
> +	 * pad sizes, while the format depends on the active route.
> +	 */
> +
> +	if (format->pad != MALI_C55_RZR_SOURCE_PAD)
> +		return mali_c55_rzr_set_sink_fmt(sd, state, format);
> +
> +	return mali_c55_rzr_set_source_fmt(sd, state, format);
> +}
> +
> +static int mali_c55_rzr_get_selection(struct v4l2_subdev *sd,
> +				      struct v4l2_subdev_state *state,
> +				      struct v4l2_subdev_selection *sel)
> +{
> +	if (sel->pad != MALI_C55_RZR_SINK_PAD)
> +		return -EINVAL;
> +
> +	if (sel->target != V4L2_SEL_TGT_CROP &&
> +	    sel->target != V4L2_SEL_TGT_COMPOSE)
> +		return -EINVAL;
> +
> +	sel->r = sel->target == V4L2_SEL_TGT_CROP
> +	       ? *v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD)
> +	       : *v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD);
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_set_selection(struct v4l2_subdev *sd,
> +				      struct v4l2_subdev_state *state,
> +				      struct v4l2_subdev_selection *sel)
> +{
> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
> +						    sd);
> +	struct v4l2_mbus_framefmt *source_fmt;
> +	struct v4l2_mbus_framefmt *sink_fmt;
> +	struct v4l2_rect *crop, *compose;
> +
> +	if (sel->pad != MALI_C55_RZR_SINK_PAD)
> +		return -EINVAL;
> +
> +	if (sel->target != V4L2_SEL_TGT_CROP &&
> +	    sel->target != V4L2_SEL_TGT_COMPOSE)
> +		return -EINVAL;
> +
> +	source_fmt = v4l2_subdev_state_get_format(state,
> +						  MALI_C55_RZR_SOURCE_PAD);
> +	sink_fmt = v4l2_subdev_state_get_format(state, MALI_C55_RZR_SINK_PAD);
> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD);
> +	compose = v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD);
> +
> +	/* RAW bypass disables crop/scaling. */
> +	if (mali_c55_format_is_raw(source_fmt->code)) {
> +		crop->top = compose->top = 0;
> +		crop->left = compose->left = 0;
> +		crop->width = compose->width = sink_fmt->width;
> +		crop->height = compose->height = sink_fmt->height;
> +
> +		sel->r = sel->target == V4L2_SEL_TGT_CROP ? *crop : *compose;
> +
> +		return 0;
> +	}
> +
> +	/* During streaming, it is allowed to only change the crop rectangle. */
> +	if (rzr->streaming && sel->target != V4L2_SEL_TGT_CROP)
> +		return -EINVAL;
> +
> +	 /*
> +	  * Update the desired target and then clamp the crop rectangle to the
> +	  * sink format sizes and the compose size to the crop sizes.
> +	  */
> +	if (sel->target == V4L2_SEL_TGT_CROP)
> +		*crop = sel->r;
> +	else
> +		*compose = sel->r;
> +
> +	clamp_t(unsigned int, crop->left, 0,  sink_fmt->width);
> +	clamp_t(unsigned int, crop->top, 0,  sink_fmt->height);
> +	clamp_t(unsigned int, crop->width, MALI_C55_MIN_WIDTH,
> +		sink_fmt->width - crop->left);
> +	clamp_t(unsigned int, crop->height, MALI_C55_MIN_HEIGHT,
> +		sink_fmt->height - crop->top);
> +
> +	if (rzr->streaming) {
> +		/*
> +		 * Apply at runtime a crop rectangle on the resizer's sink only
> +		 * if it doesn't require re-programming the scaler output sizes
> +		 * as it would require changing the output buffer sizes as well.
> +		 */
> +		if (sel->r.width < compose->width ||
> +		    sel->r.height < compose->height)
> +			return -EINVAL;
> +
> +		*crop = sel->r;
> +		mali_c55_rzr_program(rzr, state);
> +
> +		return 0;
> +	}
> +
> +	compose->left = 0;
> +	compose->top = 0;
> +	clamp_t(unsigned int, compose->left, 0,  sink_fmt->width);
> +	clamp_t(unsigned int, compose->top, 0,  sink_fmt->height);
> +	clamp_t(unsigned int, compose->width, crop->width / 8, crop->width);
> +	clamp_t(unsigned int, compose->height, crop->height / 8, crop->height);
> +
> +	sel->r = sel->target == V4L2_SEL_TGT_CROP ? *crop : *compose;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_rzr_set_routing(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_state *state,
> +				    enum v4l2_subdev_format_whence which,
> +				    struct v4l2_subdev_krouting *routing)
> +{
> +	if (which == V4L2_SUBDEV_FORMAT_ACTIVE &&
> +	    media_entity_is_streaming(&sd->entity))
> +		return -EBUSY;
> +
> +	return __mali_c55_rzr_set_routing(sd, state, routing);
> +}
> +
> +static const struct v4l2_subdev_pad_ops mali_c55_resizer_pad_ops = {
> +	.enum_mbus_code		= mali_c55_rzr_enum_mbus_code,
> +	.enum_frame_size	= mali_c55_rzr_enum_frame_size,
> +	.get_fmt		= v4l2_subdev_get_fmt,
> +	.set_fmt		= mali_c55_rzr_set_fmt,
> +	.get_selection		= mali_c55_rzr_get_selection,
> +	.set_selection		= mali_c55_rzr_set_selection,
> +	.set_routing		= mali_c55_rzr_set_routing,
> +};
> +
> +void mali_c55_rzr_start_stream(struct mali_c55_resizer *rzr)
> +{
> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
> +	struct v4l2_subdev *sd = &rzr->sd;
> +	struct v4l2_subdev_state *state;
> +	unsigned int sink_pad;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> +	sink_pad = mali_c55_rzr_get_active_sink(state);
> +	if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
> +		/* Bypass FR pipe processing if the bypass route is active. */
> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
> +				     MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK,
> +				     MALI_C55_ISP_RAW_BYPASS_RAW_FR_BYPASS);
> +		goto unlock_state;
> +	}
> +
> +	/* Disable bypass and use regular processing. */
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
> +			     MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK, 0);
> +	mali_c55_rzr_program(rzr, state);
> +
> +unlock_state:
> +	rzr->streaming = true;
> +	v4l2_subdev_unlock_state(state);
> +}
> +
> +void mali_c55_rzr_stop_stream(struct mali_c55_resizer *rzr)
> +{
> +	struct v4l2_subdev *sd = &rzr->sd;
> +	struct v4l2_subdev_state *state;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +	rzr->streaming = false;
> +	v4l2_subdev_unlock_state(state);
> +}
> +
> +static const struct v4l2_subdev_ops mali_c55_resizer_ops = {
> +	.pad	= &mali_c55_resizer_pad_ops,
> +};
> +
> +static int mali_c55_rzr_init_state(struct v4l2_subdev *sd,
> +				   struct v4l2_subdev_state *state)
> +{
> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
> +						    sd);
> +	struct v4l2_subdev_krouting routing = { };
> +	struct v4l2_subdev_route *routes;
> +	unsigned int i;
> +	int ret;
> +
> +	routes = kcalloc(rzr->num_routes, sizeof(*routes), GFP_KERNEL);
> +	if (!routes)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < rzr->num_routes; ++i) {
> +		struct v4l2_subdev_route *route = &routes[i];
> +
> +		route->sink_pad = i
> +				? MALI_C55_RZR_SINK_BYPASS_PAD
> +				: MALI_C55_RZR_SINK_PAD;
> +		route->source_pad = MALI_C55_RZR_SOURCE_PAD;
> +		if (route->sink_pad != MALI_C55_RZR_SINK_BYPASS_PAD)
> +			route->flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE;
> +	}
> +
> +	routing.num_routes = rzr->num_routes;
> +	routing.routes = routes;
> +
> +	ret = __mali_c55_rzr_set_routing(sd, state, &routing);
> +	kfree(routes);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_subdev_internal_ops mali_c55_resizer_internal_ops = {
> +	.init_state = mali_c55_rzr_init_state,
> +};
> +
> +static void mali_c55_resizer_program_coefficients(struct mali_c55 *mali_c55,
> +						  unsigned int index)
> +{
> +	unsigned int scaler_filt_coefmem_addrs[][2] = {

This should be const.

> +		[MALI_C55_RZR_FR] = {
> +			0x034A8, /* hfilt */
> +			0x044A8  /* vfilt */
> +		},
> +		[MALI_C55_RZR_DS] = {
> +			0x014A8, /* hfilt */
> +			0x024A8  /* vfilt */
> +		},
> +	};
> +	unsigned int haddr = scaler_filt_coefmem_addrs[index][0];
> +	unsigned int vaddr = scaler_filt_coefmem_addrs[index][1];
> +	unsigned int i, j;
> +
> +	for (i = 0; i < MALI_C55_RESIZER_COEFS_NUM_BANKS; i++) {
> +		for (j = 0; j < MALI_C55_RESIZER_COEFS_NUM_ENTRIES; j++) {
> +			mali_c55_write(mali_c55, haddr,
> +				mali_c55_scaler_h_filter_coefficients[i][j]);
> +			mali_c55_write(mali_c55, vaddr,
> +				mali_c55_scaler_v_filter_coefficients[i][j]);
> +
> +			haddr += 4;
> +			vaddr += 4;

sizeof(u32) ?

Up to you.

> +		}
> +	}
> +}
> +
> +int mali_c55_register_resizers(struct mali_c55 *mali_c55)
> +{
> +	unsigned int i;
> +	int ret;
> +
> +	for (i = 0; i < MALI_C55_NUM_RZRS; ++i) {
> +		struct mali_c55_resizer *rzr = &mali_c55->resizers[i];
> +		struct v4l2_subdev *sd = &rzr->sd;
> +		unsigned int num_pads = MALI_C55_RZR_NUM_PADS;
> +
> +		rzr->id = i;
> +		rzr->streaming = false;
> +
> +		if (rzr->id == MALI_C55_RZR_FR)
> +			rzr->cap_dev = &mali_c55->cap_devs[MALI_C55_CAP_DEV_FR];
> +		else
> +			rzr->cap_dev = &mali_c55->cap_devs[MALI_C55_CAP_DEV_DS];
> +
> +		mali_c55_resizer_program_coefficients(mali_c55, i);
> +
> +		v4l2_subdev_init(sd, &mali_c55_resizer_ops);
> +		sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE
> +			  | V4L2_SUBDEV_FL_STREAMS;

"|" should be aligned with beginning of the rvalue, i.e. "V" of
V4L2_SUBDEV_FL_HAS_DEVNODE.

> +		sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
> +		sd->owner = THIS_MODULE;
> +		sd->internal_ops = &mali_c55_resizer_internal_ops;
> +		snprintf(sd->name, ARRAY_SIZE(sd->name), "%s %s",
> +			 MALI_C55_DRIVER_NAME, mali_c55_resizer_names[i]);
> +
> +		rzr->pads[MALI_C55_RZR_SINK_PAD].flags = MEDIA_PAD_FL_SINK;
> +		rzr->pads[MALI_C55_RZR_SOURCE_PAD].flags = MEDIA_PAD_FL_SOURCE;
> +
> +		/* Only the FR pipe has a bypass pad. */
> +		if (rzr->id == MALI_C55_RZR_FR) {
> +			rzr->pads[MALI_C55_RZR_SINK_BYPASS_PAD].flags =
> +							MEDIA_PAD_FL_SINK;
> +			rzr->num_routes = 2;
> +		} else {
> +			num_pads -= 1;
> +			rzr->num_routes = 1;
> +		}
> +
> +		ret = media_entity_pads_init(&sd->entity, num_pads, rzr->pads);
> +		if (ret)
> +			return ret;
> +
> +		ret = v4l2_subdev_init_finalize(sd);
> +		if (ret)
> +			goto err_cleanup;
> +
> +		ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
> +		if (ret)
> +			goto err_cleanup;
> +
> +		rzr->mali_c55 = mali_c55;
> +	}
> +
> +	return 0;
> +
> +err_cleanup:
> +	for (; i >= 0; --i) {
> +		struct mali_c55_resizer *rzr = &mali_c55->resizers[i];
> +		struct v4l2_subdev *sd = &rzr->sd;
> +
> +		v4l2_subdev_cleanup(sd);
> +		media_entity_cleanup(&sd->entity);
> +	}
> +
> +	return ret;
> +}
> +
> +void mali_c55_unregister_resizers(struct mali_c55 *mali_c55)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < MALI_C55_NUM_RZRS; i++) {
> +		struct mali_c55_resizer *resizer = &mali_c55->resizers[i];
> +
> +		if (!resizer->mali_c55)
> +			continue;
> +
> +		v4l2_device_unregister_subdev(&resizer->sd);
> +		v4l2_subdev_cleanup(&resizer->sd);
> +		media_entity_cleanup(&resizer->sd.entity);
> +	}
> +}
> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c b/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
> new file mode 100644
> index 000000000000..042851a4b42d
> --- /dev/null
> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
> @@ -0,0 +1,424 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ARM Mali-C55 ISP Driver - Test pattern generator
> + *
> + * Copyright (C) 2024 Ideas on Board Oy
> + */
> +
> +#include <linux/minmax.h>
> +#include <linux/string.h>
> +
> +#include <media/media-entity.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-subdev.h>
> +
> +#include "mali-c55-common.h"
> +#include "mali-c55-registers.h"
> +
> +#define MALI_C55_TPG_SRC_PAD		0
> +#define MALI_C55_TPG_FIXED_HBLANK	0x20
> +#define MALI_C55_TPG_MAX_VBLANK		0xFFFF
> +#define MALI_C55_TPG_PIXEL_RATE		100000000
> +
> +static const char * const mali_c55_tpg_test_pattern_menu[] = {
> +	"Flat field",
> +	"Horizontal gradient",
> +	"Vertical gradient",
> +	"Vertical bars",
> +	"Arbitrary rectangle",
> +	"White frame on black field"
> +};
> +
> +static const u32 mali_c55_tpg_mbus_codes[] = {
> +	MEDIA_BUS_FMT_SRGGB16_1X16,
> +	/*
> +	 * This is a lie. In RGB mode the Test Pattern Generator actually output
> +	 * 16-bits-per-colour data. However, RGB data follows one of the Bypass
> +	 * paths which has a 12-bit limit at the insertion point, meaning it
> +	 * would be truncated there to match the internal 12-bit format that
> +	 * would be output from the debayering block. The same is true of RGB
> +	 * data output by a sensor and streamed to the ISP's input port, however
> +	 * in that case the ISP's input port requires that data be converted to
> +	 * a 20-bit MSB aligned format. Given:
> +	 *
> +	 *	1. Our chosen topology represents the TPG as a subdevice
> +	 *	   linked to the ISP's input port.
> +	 *	2. We need to restrict the ISP's sink pad to only accepting that
> +	 *	   20-bit RGB format from sensors / CSI-2 receivers.
> +	 *	3. All the data ultimately ends up in the same format anyway and
> +	 *	   these data from the TPG are purely internal to the ISP
> +	 *
> +	 * It seems best to reduce the programming complexity by simply
> +	 * pretending that the TPG outputs data in the same format that the ISP
> +	 * input port requires, even though it doesn't really.
> +	 */
> +	MEDIA_BUS_FMT_RGB202020_1X60,
> +};
> +
> +static void __mali_c55_tpg_calc_vblank(struct v4l2_mbus_framefmt *format,
> +				       int *def_vblank, int *min_vblank)
> +{
> +	unsigned int hts;
> +	int tgt_fps;
> +	int vblank;
> +
> +	hts = format->width + MALI_C55_TPG_FIXED_HBLANK;
> +
> +	/*
> +	 * The ISP has minimum vertical blanking requirements that must be
> +	 * adhered to by the TPG. The minimum is a function of the Iridix blocks
> +	 * clocking requirements and the width of the image and horizontal
> +	 * blanking, but if we assume the worst case iVariance and sVariance
> +	 * values then it boils down to the below.
> +	 */
> +	*min_vblank = 15 + (120500 / hts);
> +
> +	/*
> +	 * We need to set a sensible default vblank for whatever format height
> +	 * we happen to be given from set_fmt(). This function just targets
> +	 * an even multiple of 15fps. If we can't get 15fps, let's target 5fps.
> +	 * If we can't get 5fps we'll take whatever the minimum vblank gives us.
> +	 */
> +	tgt_fps = MALI_C55_TPG_PIXEL_RATE / hts / (format->height + *min_vblank);
> +
> +	if (tgt_fps < 5)
> +		vblank = *min_vblank;
> +	else
> +		vblank = MALI_C55_TPG_PIXEL_RATE / hts
> +		       / max(rounddown(tgt_fps, 15), 5);
> +
> +	*def_vblank = ALIGN_DOWN(vblank, 2) - format->height;
> +}
> +
> +static int mali_c55_tpg_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct mali_c55_tpg *tpg = container_of(ctrl->handler,
> +						struct mali_c55_tpg,
> +						ctrls.handler);
> +	struct mali_c55 *mali_c55 = container_of(tpg, struct mali_c55, tpg);
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_TEST_PATTERN:
> +		mali_c55_write(mali_c55, MALI_C55_REG_TEST_GEN_CH0_PATTERN_TYPE,
> +			       ctrl->val);
> +		break;
> +	case V4L2_CID_VBLANK:
> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_BLANKING,
> +				     MALI_C55_REG_VBLANK_MASK, ctrl->val);
> +		break;
> +	default:
> +		dev_err(mali_c55->dev, "invalid V4L2 control ID\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_ctrl_ops mali_c55_tpg_ctrl_ops = {
> +	.s_ctrl = &mali_c55_tpg_s_ctrl,
> +};
> +
> +static void mali_c55_tpg_configure(struct mali_c55 *mali_c55,
> +				   struct v4l2_subdev *sd)
> +{
> +	struct v4l2_subdev_state *state;
> +	struct v4l2_mbus_framefmt *fmt;
> +
> +	/*
> +	 * hblank needs setting, but is a read-only control and thus won't be
> +	 * called during __v4l2_ctrl_handler_setup(). Do it here instead.
> +	 */
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_BLANKING,
> +			     MALI_C55_REG_HBLANK_MASK,
> +			     MALI_C55_TPG_FIXED_HBLANK);
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
> +			     MALI_C55_REG_GEN_VIDEO_MULTI_MASK, 0x01);
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +	fmt = v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD);
> +
> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
> +			     MALI_C55_TEST_PATTERN_RGB_MASK,
> +			     fmt->code == MEDIA_BUS_FMT_RGB202020_1X60 ?
> +					  0x01 : 0x0);
> +
> +	v4l2_subdev_unlock_state(state);
> +}
> +
> +static int mali_c55_tpg_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct mali_c55_tpg *tpg = container_of(sd, struct mali_c55_tpg, sd);
> +	struct mali_c55 *mali_c55 = container_of(tpg, struct mali_c55, tpg);
> +
> +	if (!enable) {
> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
> +				     MALI_C55_TEST_PATTERN_ON_OFF, 0x00);
> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
> +				     MALI_C55_REG_GEN_VIDEO_ON_MASK, 0x00);
> +	} else {
> +		/*
> +		 * One might reasonably expect the framesize to be set here
> +		 * given it's configurable in .set_fmt(), but it's done in the
> +		 * ISP subdevice's .s_stream() instead, as the same register is
> +		 * also used to indicate the size of the data coming from the
> +		 * sensor.
> +		 */
> +		mali_c55_tpg_configure(mali_c55, sd);
> +		__v4l2_ctrl_handler_setup(sd->ctrl_handler);
> +
> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
> +				     MALI_C55_TEST_PATTERN_ON_OFF,
> +				     MALI_C55_TEST_PATTERN_ON_OFF);
> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
> +				     MALI_C55_REG_GEN_VIDEO_ON_MASK,
> +				     MALI_C55_REG_GEN_VIDEO_ON_MASK);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops mali_c55_tpg_video_ops = {
> +	.s_stream = &mali_c55_tpg_s_stream,
> +};
> +
> +static int mali_c55_tpg_enum_mbus_code(struct v4l2_subdev *sd,
> +				       struct v4l2_subdev_state *state,
> +				       struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	if (code->pad >= sd->entity.num_pads)
> +		return -EINVAL;

This check is done by the framework, you can drop it here.

> +
> +	if (code->index >= ARRAY_SIZE(mali_c55_tpg_mbus_codes))
> +		return -EINVAL;
> +
> +	code->code = mali_c55_tpg_mbus_codes[code->index];
> +
> +	return 0;
> +}
> +
> +static int mali_c55_tpg_enum_frame_size(struct v4l2_subdev *sd,
> +					struct v4l2_subdev_state *state,
> +					struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	if (fse->index > 0 || fse->pad > sd->entity.num_pads)
> +		return -EINVAL;
> +
> +	fse->min_width = MALI_C55_MIN_WIDTH;
> +	fse->max_width = MALI_C55_MAX_WIDTH;
> +	fse->min_height = MALI_C55_MIN_HEIGHT;
> +	fse->max_height = MALI_C55_MAX_HEIGHT;
> +
> +	return 0;
> +}
> +
> +static int mali_c55_tpg_set_fmt(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *state,
> +				struct v4l2_subdev_format *format)
> +{
> +	struct mali_c55_tpg *tpg = container_of(sd, struct mali_c55_tpg, sd);
> +	struct v4l2_mbus_framefmt *fmt = &format->format;
> +	int vblank_def, vblank_min;
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(mali_c55_tpg_mbus_codes); i++) {
> +		if (fmt->code == mali_c55_tpg_mbus_codes[i])
> +			break;
> +	}
> +
> +	if (i == ARRAY_SIZE(mali_c55_tpg_mbus_codes))
> +		fmt->code = MEDIA_BUS_FMT_SRGGB16_1X16;
> +
> +	/*
> +	 * The TPG says that the test frame timing generation logic expects a
> +	 * minimum framesize of 4x4 pixels, but given the rest of the ISP can't
> +	 * handle anything smaller than 128x128 it seems pointless to allow a
> +	 * smaller frame.
> +	 */
> +	clamp_t(unsigned int, fmt->width, MALI_C55_MIN_WIDTH,
> +		MALI_C55_MAX_WIDTH);
> +	clamp_t(unsigned int, fmt->height, MALI_C55_MIN_HEIGHT,
> +		MALI_C55_MAX_HEIGHT);
> +
> +	*v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD) = *fmt;
> +

Shouldn't the controls below only be changed for the active format?

> +	__mali_c55_tpg_calc_vblank(fmt, &vblank_def, &vblank_min);
> +	__v4l2_ctrl_modify_range(tpg->ctrls.vblank, vblank_min,
> +				 MALI_C55_TPG_MAX_VBLANK, 1, vblank_def);
> +	__v4l2_ctrl_s_ctrl(tpg->ctrls.vblank, vblank_def);
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_pad_ops mali_c55_tpg_pad_ops = {
> +	.enum_mbus_code		= mali_c55_tpg_enum_mbus_code,
> +	.enum_frame_size	= mali_c55_tpg_enum_frame_size,
> +	.get_fmt		= v4l2_subdev_get_fmt,
> +	.set_fmt		= mali_c55_tpg_set_fmt,
> +};
> +
> +static const struct v4l2_subdev_ops mali_c55_tpg_ops = {
> +	.video	= &mali_c55_tpg_video_ops,
> +	.pad	= &mali_c55_tpg_pad_ops,
> +};
> +
> +static int mali_c55_tpg_init_state(struct v4l2_subdev *sd,
> +				   struct v4l2_subdev_state *sd_state)
> +{
> +	struct v4l2_mbus_framefmt *fmt;
> +
> +	fmt = v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);

Can be assigned in the declaration.

> +
> +	fmt->width = MALI_C55_DEFAULT_WIDTH;
> +	fmt->height = MALI_C55_DEFAULT_HEIGHT;
> +	fmt->field = V4L2_FIELD_NONE;
> +	fmt->code = MEDIA_BUS_FMT_SRGGB16_1X16;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_internal_ops mali_c55_tpg_internal_ops = {
> +	.init_state = mali_c55_tpg_init_state,
> +};
> +
> +static int mali_c55_tpg_init_controls(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_tpg_ctrls *ctrls = &mali_c55->tpg.ctrls;
> +	struct v4l2_subdev *sd = &mali_c55->tpg.sd;
> +	struct v4l2_mbus_framefmt *format;
> +	struct v4l2_subdev_state *state;
> +	int vblank_def, vblank_min;
> +	int ret;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +	format = v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD);
> +
> +	ret = v4l2_ctrl_handler_init(&ctrls->handler, 1);
> +	if (ret)
> +		goto err_unlock;
> +
> +	ctrls->test_pattern = v4l2_ctrl_new_std_menu_items(&ctrls->handler,
> +				&mali_c55_tpg_ctrl_ops, V4L2_CID_TEST_PATTERN,
> +				ARRAY_SIZE(mali_c55_tpg_test_pattern_menu) - 1,
> +				0, 3, mali_c55_tpg_test_pattern_menu);
> +
> +	/*
> +	 * We fix hblank at the minimum allowed value and control framerate
> +	 * solely through the vblank control.
> +	 */
> +	ctrls->hblank = v4l2_ctrl_new_std(&ctrls->handler,
> +				&mali_c55_tpg_ctrl_ops,
> +				V4L2_CID_HBLANK, MALI_C55_TPG_FIXED_HBLANK,
> +				MALI_C55_TPG_FIXED_HBLANK, 1,
> +				MALI_C55_TPG_FIXED_HBLANK);
> +	if (ctrls->hblank)
> +		ctrls->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> +	__mali_c55_tpg_calc_vblank(format, &vblank_def, &vblank_min);
> +	ctrls->vblank = v4l2_ctrl_new_std(&ctrls->handler,
> +					  &mali_c55_tpg_ctrl_ops,
> +					  V4L2_CID_VBLANK, vblank_min,
> +					  MALI_C55_TPG_MAX_VBLANK, 1,
> +					  vblank_def);
> +
> +	if (ctrls->handler.error) {
> +		dev_err(mali_c55->dev, "Error during v4l2 controls init\n");
> +		ret = ctrls->handler.error;
> +		goto err_free_handler;
> +	}
> +
> +	ctrls->handler.lock = &mali_c55->tpg.lock;
> +	mali_c55->tpg.sd.ctrl_handler = &ctrls->handler;
> +
> +	v4l2_subdev_unlock_state(state);
> +
> +	return 0;
> +
> +err_free_handler:
> +	v4l2_ctrl_handler_free(&ctrls->handler);
> +err_unlock:
> +	v4l2_subdev_unlock_state(state);
> +	return ret;
> +}
> +
> +int mali_c55_register_tpg(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_tpg *tpg = &mali_c55->tpg;
> +	struct v4l2_subdev *sd = &tpg->sd;
> +	struct media_pad *pad = &tpg->pad;
> +	int ret;
> +
> +	mutex_init(&tpg->lock);
> +
> +	v4l2_subdev_init(sd, &mali_c55_tpg_ops);
> +	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	sd->entity.function = MEDIA_ENT_F_CAM_SENSOR;
> +	sd->owner = THIS_MODULE;
> +	sd->internal_ops = &mali_c55_tpg_internal_ops;
> +	strscpy(sd->name, MALI_C55_DRIVER_NAME " tpg", sizeof(sd->name));
> +
> +	pad->flags = MEDIA_PAD_FL_SOURCE | MEDIA_PAD_FL_MUST_CONNECT;
> +	ret = media_entity_pads_init(&sd->entity, 1, pad);
> +	if (ret) {
> +		dev_err(mali_c55->dev,
> +			"Failed to initialize media entity pads\n");
> +		goto err_destroy_mutex;
> +	}
> +
> +	ret = v4l2_subdev_init_finalize(sd);
> +	if (ret)
> +		goto err_cleanup_media_entity;
> +
> +	ret = mali_c55_tpg_init_controls(mali_c55);
> +	if (ret) {
> +		dev_err(mali_c55->dev,
> +			"Error initialising controls\n");
> +		goto err_cleanup_subdev;
> +	}
> +
> +	ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
> +	if (ret) {
> +		dev_err(mali_c55->dev, "Failed to register tpg subdev\n");
> +		goto err_free_ctrl_handler;
> +	}
> +
> +	/*
> +	 * By default the colour settings lead to a very dim image that is
> +	 * nearly indistinguishable from black on some monitor settings. Ramp
> +	 * them up a bit so the image is brighter.
> +	 */
> +	mali_c55_write(mali_c55, MALI_C55_REG_TPG_R_BACKGROUND,
> +		       MALI_C55_TPG_BACKGROUND_MAX);
> +	mali_c55_write(mali_c55, MALI_C55_REG_TPG_G_BACKGROUND,
> +		       MALI_C55_TPG_BACKGROUND_MAX);
> +	mali_c55_write(mali_c55, MALI_C55_REG_TPG_B_BACKGROUND,
> +		       MALI_C55_TPG_BACKGROUND_MAX);
> +
> +	tpg->mali_c55 = mali_c55;
> +
> +	return 0;
> +
> +err_free_ctrl_handler:
> +	v4l2_ctrl_handler_free(&tpg->ctrls.handler);
> +err_cleanup_subdev:
> +	v4l2_subdev_cleanup(sd);
> +err_cleanup_media_entity:
> +	media_entity_cleanup(&sd->entity);
> +err_destroy_mutex:
> +	mutex_destroy(&tpg->lock);
> +
> +	return ret;
> +}
> +
> +void mali_c55_unregister_tpg(struct mali_c55 *mali_c55)
> +{
> +	struct mali_c55_tpg *tpg = &mali_c55->tpg;
> +
> +	if (!tpg->mali_c55)
> +		return;
> +
> +	v4l2_device_unregister_subdev(&tpg->sd);
> +	v4l2_subdev_cleanup(&tpg->sd);
> +	media_entity_cleanup(&tpg->sd.entity);
> +	v4l2_ctrl_handler_free(&tpg->ctrls.handler);
> +	mutex_destroy(&tpg->lock);
> +}

Jacopo Mondi May 23, 2024, 9:48 a.m. UTC | #2

Hi Sakari

On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
> Hi Daniel,

[snip]

>
> > +
> > +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
> > +{
> > +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> > +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> > +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> > +	struct mali_c55_isp *isp = &mali_c55->isp;
> > +	int ret;
> > +
> > +	guard(mutex)(&isp->lock);
> > +
> > +	ret = pm_runtime_resume_and_get(mali_c55->dev);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = video_device_pipeline_start(&cap_dev->vdev,
> > +					  &cap_dev->mali_c55->pipe);
> > +	if (ret) {
> > +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
> > +			mali_c55_cap_dev_to_name(cap_dev));
> > +		goto err_pm_put;
> > +	}
> > +
> > +	mali_c55_cap_dev_stream_enable(cap_dev);
> > +	mali_c55_rzr_start_stream(rzr);
> > +
> > +	/*
> > +	 * We only start the ISP if we're the only capture device that's
> > +	 * streaming. Otherwise, it'll already be active.
> > +	 */
> > +	if (mali_c55->pipe.start_count == 1) {
>
> Do you start streaming on the sensor when the first video node does?
>
> This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
> streaming on the sensor once all video nodes of the pipeline have been
> started.
>

How would you ever know which nodes will be started ?

Laurent Pinchart May 23, 2024, 9:49 a.m. UTC | #3

On Thu, May 23, 2024 at 11:48:02AM +0200, Jacopo Mondi wrote:
> On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
> > Hi Daniel,
> 
> [snip]
> 
> > > +
> > > +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
> > > +{
> > > +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> > > +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> > > +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> > > +	struct mali_c55_isp *isp = &mali_c55->isp;
> > > +	int ret;
> > > +
> > > +	guard(mutex)(&isp->lock);
> > > +
> > > +	ret = pm_runtime_resume_and_get(mali_c55->dev);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ret = video_device_pipeline_start(&cap_dev->vdev,
> > > +					  &cap_dev->mali_c55->pipe);
> > > +	if (ret) {
> > > +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
> > > +			mali_c55_cap_dev_to_name(cap_dev));
> > > +		goto err_pm_put;
> > > +	}
> > > +
> > > +	mali_c55_cap_dev_stream_enable(cap_dev);
> > > +	mali_c55_rzr_start_stream(rzr);
> > > +
> > > +	/*
> > > +	 * We only start the ISP if we're the only capture device that's
> > > +	 * streaming. Otherwise, it'll already be active.
> > > +	 */
> > > +	if (mali_c55->pipe.start_count == 1) {
> >
> > Do you start streaming on the sensor when the first video node does?
> >
> > This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
> > streaming on the sensor once all video nodes of the pipeline have been
> > started.
> 
> How would you ever know which nodes will be started ?

That can be done with link setup. Any video device that has an active
link to the ISP would need to be started.

Dan Scally May 23, 2024, 11:22 a.m. UTC | #4

Hello

On 23/05/2024 10:49, Laurent Pinchart wrote:
> On Thu, May 23, 2024 at 11:48:02AM +0200, Jacopo Mondi wrote:
>> On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
>>> Hi Daniel,
>> [snip]
>>
>>>> +
>>>> +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
>>>> +{
>>>> +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
>>>> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
>>>> +	struct mali_c55_resizer *rzr = cap_dev->rzr;
>>>> +	struct mali_c55_isp *isp = &mali_c55->isp;
>>>> +	int ret;
>>>> +
>>>> +	guard(mutex)(&isp->lock);
>>>> +
>>>> +	ret = pm_runtime_resume_and_get(mali_c55->dev);
>>>> +	if (ret)
>>>> +		return ret;
>>>> +
>>>> +	ret = video_device_pipeline_start(&cap_dev->vdev,
>>>> +					  &cap_dev->mali_c55->pipe);
>>>> +	if (ret) {
>>>> +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
>>>> +			mali_c55_cap_dev_to_name(cap_dev));
>>>> +		goto err_pm_put;
>>>> +	}
>>>> +
>>>> +	mali_c55_cap_dev_stream_enable(cap_dev);
>>>> +	mali_c55_rzr_start_stream(rzr);
>>>> +
>>>> +	/*
>>>> +	 * We only start the ISP if we're the only capture device that's
>>>> +	 * streaming. Otherwise, it'll already be active.
>>>> +	 */
>>>> +	if (mali_c55->pipe.start_count == 1) {
>>> Do you start streaming on the sensor when the first video node does?
>>>
>>> This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
>>> streaming on the sensor once all video nodes of the pipeline have been
>>> started.
>> How would you ever know which nodes will be started ?
> That can be done with link setup. Any video device that has an active
> link to the ISP would need to be started.


So if you don't want to stream data from one of the two capture nodes, you'd need to disable the 
link between it and the resizer? That seems quite clunky. Does it matter if one of them starts a 
frame or two later? As opposed to both of them starting in sync a frame or two later?

>

Dan Scally May 23, 2024, 1:44 p.m. UTC | #5

Hi Sakari - thanks for the review. Snipping some bits for which I have no comment...

On 23/05/2024 09:03, Sakari Ailus wrote:

<snip>
>> +
>> +static unsigned int mali_c55_calculate_bank_num(struct mali_c55 *mali_c55,
>> +						unsigned int crop,
>> +						unsigned int scale)
>> +{
>> +	unsigned int tmp;
>> +	unsigned int i;
>> +
>> +	tmp = (scale * 1000) / crop;
> This looks like something that can overflow. Can it?


Shouldn't be able to; maximum scale width is 8192.

>
>> +
>> +	for (i = 0; i < ARRAY_SIZE(mali_c55_coefficient_banks); i++) {
>> +		if (tmp >= mali_c55_coefficient_banks[i].bottom &&
>> +		    tmp <= mali_c55_coefficient_banks[i].top)
>> +			return mali_c55_coefficient_banks[i].bank;
>> +	}
>> +
>> +	/*
>> +	 * We shouldn't ever get here, in theory. As we have no good choices
>> +	 * simply warn the user and use the first bank of coefficients.
>> +	 */
>> +	dev_warn(mali_c55->dev, "scaling factor outside defined bounds\n");
>> +	return 0;
>> +}
>> +
>> +#endif /* _MALI_C55_RESIZER_COEFS_H */
>> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c b/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
>> new file mode 100644
>> index 000000000000..8e0669a5f391
>> --- /dev/null
>> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
>> @@ -0,0 +1,740 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * ARM Mali-C55 ISP Driver - Image signal processor
>> + *
>> + * Copyright (C) 2024 Ideas on Board Oy
>> + */
>> +
>> +#include <linux/math.h>
>> +#include <linux/minmax.h>
>> +
>> +#include <media/media-entity.h>
>> +#include <media/v4l2-subdev.h>
>> +
>> +#include "mali-c55-common.h"
>> +#include "mali-c55-registers.h"
>> +#include "mali-c55-resizer-coefs.h"
>> +
>> +/* Scaling factor in Q4.20 format. */
>> +#define MALI_C55_RZR_SCALER_FACTOR	1048576
> (1U << 20)
>
> ?
>
>> +
>> +static const u32 rzr_non_bypass_src_fmts[] = {
>> +	MEDIA_BUS_FMT_RGB121212_1X36,
>> +	MEDIA_BUS_FMT_YUV10_1X30
>> +};
>> +
>> +static const char * const mali_c55_resizer_names[] = {
>> +	[MALI_C55_RZR_FR] = "resizer fr",
>> +	[MALI_C55_RZR_DS] = "resizer ds",
>> +};
>> +
>> +static int mali_c55_rzr_program_crop(struct mali_c55_resizer *rzr,
>> +				     struct v4l2_subdev_state *state)
>> +{
>> +	unsigned int reg_offset = rzr->cap_dev->reg_offset;
>> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
>> +	struct v4l2_mbus_framefmt *fmt;
>> +	struct v4l2_rect *crop;
>> +
>> +	/* Verify if crop should be enabled. */
>> +	fmt = v4l2_subdev_state_get_format(state, MALI_C55_RZR_SINK_PAD, 0);
>> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD, 0);
>> +
>> +	if (fmt->width == crop->width && fmt->height == crop->height)
>> +		return MALI_C55_BYPASS_CROP;
>> +
>> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_X_START(reg_offset),
>> +		       crop->left);
>> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_Y_START(reg_offset),
>> +		       crop->top);
>> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_X_SIZE(reg_offset),
>> +		       crop->width);
>> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_Y_SIZE(reg_offset),
>> +		       crop->height);
>> +
>> +	mali_c55_write(mali_c55, MALI_C55_REG_CROP_EN(reg_offset),
>> +		       MALI_C55_CROP_ENABLE);
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_program_resizer(struct mali_c55_resizer *rzr,
>> +					struct v4l2_subdev_state *state)
>> +{
>> +	unsigned int reg_offset = rzr->cap_dev->reg_offset;
>> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
>> +	struct v4l2_rect *crop, *scale;
>> +	unsigned int h_bank, v_bank;
>> +	u64 h_scale, v_scale;
>> +
>> +	/* Verify if scaling should be enabled. */
>> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD, 0);
>> +	scale = v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD, 0);
>> +
>> +	if (crop->width == scale->width && crop->height == scale->height)
>> +		return MALI_C55_BYPASS_SCALER;
>> +
>> +	/* Program the V/H scaling factor in Q4.20 format. */
>> +	h_scale = crop->width * MALI_C55_RZR_SCALER_FACTOR;
>> +	v_scale = crop->height * MALI_C55_RZR_SCALER_FACTOR;
>> +
>> +	do_div(h_scale, scale->width);
>> +	do_div(v_scale, scale->height);
>> +
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_IN_WIDTH(reg_offset),
>> +		       crop->width);
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_IN_HEIGHT(reg_offset),
>> +		       crop->height);
>> +
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_OUT_WIDTH(reg_offset),
>> +		       scale->width);
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_OUT_HEIGHT(reg_offset),
>> +		       scale->height);
>> +
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_HFILT_TINC(reg_offset),
>> +		       h_scale);
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_VFILT_TINC(reg_offset),
>> +		       v_scale);
>> +
>> +	h_bank = mali_c55_calculate_bank_num(mali_c55, crop->width,
>> +					     scale->width);
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_HFILT_COEF(reg_offset),
>> +		       h_bank);
>> +
>> +	v_bank = mali_c55_calculate_bank_num(mali_c55, crop->height,
>> +					     scale->height);
>> +	mali_c55_write(mali_c55,
>> +		       MALI_C55_REG_SCALER_VFILT_COEF(reg_offset),
>> +		       v_bank);
>> +
>> +	return 0;
>> +}
>> +
>> +static void mali_c55_rzr_program(struct mali_c55_resizer *rzr,
>> +				 struct v4l2_subdev_state *state)
>> +{
>> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
>> +	u32 bypass = 0;
>> +
>> +	/* Verify if cropping and scaling should be enabled. */
>> +	bypass |= mali_c55_rzr_program_crop(rzr, state);
>> +	bypass |= mali_c55_rzr_program_resizer(rzr, state);
>> +
>> +	mali_c55_update_bits(mali_c55, rzr->id == MALI_C55_RZR_FR ?
>> +			     MALI_C55_REG_FR_BYPASS : MALI_C55_REG_DS_BYPASS,
>> +			     MALI_C55_BYPASS_CROP | MALI_C55_BYPASS_SCALER,
>> +			     bypass);
>> +}
>> +
>> +/*
>> + * Inspect the routing table to know which of the two (mutually exclusive)
>> + * routes is enabled and return the sink pad id of the active route.
>> + */
>> +static unsigned int mali_c55_rzr_get_active_sink(struct v4l2_subdev_state *state)
>> +{
>> +	struct v4l2_subdev_krouting *routing = &state->routing;
>> +	struct v4l2_subdev_route *route;
>> +
>> +	/* A single route is enabled at a time. */
>> +	for_each_active_route(routing, route)
>> +		return route->sink_pad;
>> +
>> +	return MALI_C55_RZR_SINK_PAD;
>> +}
>> +
>> +static int __mali_c55_rzr_set_routing(struct v4l2_subdev *sd,
>> +				      struct v4l2_subdev_state *state,
>> +				      struct v4l2_subdev_krouting *routing)
>> +{
>> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
>> +						    sd);
>> +	unsigned int active_sink = UINT_MAX;
>> +	struct v4l2_rect *crop, *compose;
>> +	struct v4l2_subdev_route *route;
>> +	unsigned int active_routes = 0;
>> +	struct v4l2_mbus_framefmt *fmt;
>> +	int ret;
>> +
>> +	ret = v4l2_subdev_routing_validate(sd, routing, 0);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/* Only a single route can be enabled at a time. */
>> +	for_each_active_route(routing, route) {
>> +		if (++active_routes > 1) {
>> +			dev_err(rzr->mali_c55->dev,
>> +				"Only one route can be active");
>> +			return -EINVAL;
>> +		}
>> +
>> +		active_sink = route->sink_pad;
>> +	}
>> +	if (active_sink == UINT_MAX) {
>> +		dev_err(rzr->mali_c55->dev, "One route has to be active");
>> +		return -EINVAL;
>> +	}
>> +
>> +	ret = v4l2_subdev_set_routing(sd, state, routing);
>> +	if (ret) {
>> +		dev_err(rzr->mali_c55->dev, "Failed to set routing\n");
>> +		return ret;
>> +	}
>> +
>> +	fmt = v4l2_subdev_state_get_format(state, active_sink, 0);
>> +	crop = v4l2_subdev_state_get_crop(state, active_sink, 0);
>> +	compose = v4l2_subdev_state_get_compose(state, active_sink, 0);
>> +
>> +	fmt->width = MALI_C55_DEFAULT_WIDTH;
>> +	fmt->height = MALI_C55_DEFAULT_HEIGHT;
>> +	fmt->colorspace = V4L2_COLORSPACE_SRGB;
>> +	fmt->field = V4L2_FIELD_NONE;
>> +
>> +	if (active_sink == MALI_C55_RZR_SINK_PAD) {
>> +		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
>> +
>> +		crop->left = crop->top = 0;
>> +		crop->width = MALI_C55_DEFAULT_WIDTH;
>> +		crop->height = MALI_C55_DEFAULT_HEIGHT;
>> +
>> +		*compose = *crop;
>> +	} else {
>> +		fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
>> +	}
>> +
>> +	/* Propagate the format to the source pad */
>> +	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD, 0) = *fmt;
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_enum_mbus_code(struct v4l2_subdev *sd,
>> +				       struct v4l2_subdev_state *state,
>> +				       struct v4l2_subdev_mbus_code_enum *code)
>> +{
>> +	struct v4l2_mbus_framefmt *sink_fmt;
>> +	const struct mali_c55_isp_fmt *fmt;
>> +	unsigned int index = 0;
>> +	u32 sink_pad;
>> +
>> +	switch (code->pad) {
>> +	case MALI_C55_RZR_SINK_PAD:
>> +		if (code->index)
>> +			return -EINVAL;
>> +
>> +		code->code = MEDIA_BUS_FMT_RGB121212_1X36;
>> +
>> +		return 0;
>> +	case MALI_C55_RZR_SOURCE_PAD:
>> +		sink_pad = mali_c55_rzr_get_active_sink(state);
>> +		sink_fmt = v4l2_subdev_state_get_format(state, sink_pad, 0);
>> +
>> +		/*
>> +		 * If the active route is from the Bypass sink pad, then the
>> +		 * source pad is a simple passthrough of the sink format.
>> +		 */
>> +
>> +		if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
>> +			if (code->index)
>> +				return -EINVAL;
>> +
>> +			code->code = sink_fmt->code;
>> +			return 0;
>> +		}
>> +
>> +		/*
>> +		 * If the active route is from the non-bypass sink then we can
>> +		 * select either RGB or conversion to YUV.
>> +		 */
>> +
>> +		if (code->index >= ARRAY_SIZE(rzr_non_bypass_src_fmts))
>> +			return -EINVAL;
>> +
>> +		code->code = rzr_non_bypass_src_fmts[code->index];
>> +
>> +		return 0;
>> +	case MALI_C55_RZR_SINK_BYPASS_PAD:
>> +		for_each_mali_isp_fmt(fmt) {
>> +			if (index++ == code->index) {
>> +				code->code = fmt->code;
>> +				return 0;
>> +			}
>> +		}
>> +
>> +		break;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static int mali_c55_rzr_enum_frame_size(struct v4l2_subdev *sd,
>> +					struct v4l2_subdev_state *state,
>> +					struct v4l2_subdev_frame_size_enum *fse)
>> +{
>> +	if (fse->index)
>> +		return -EINVAL;
>> +
>> +	fse->max_width = MALI_C55_MAX_WIDTH;
>> +	fse->max_height = MALI_C55_MAX_HEIGHT;
>> +	fse->min_width = MALI_C55_MIN_WIDTH;
>> +	fse->min_height = MALI_C55_MIN_HEIGHT;
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_set_sink_fmt(struct v4l2_subdev *sd,
>> +				     struct v4l2_subdev_state *state,
>> +				     struct v4l2_subdev_format *format)
>> +{
>> +	struct v4l2_mbus_framefmt *fmt = &format->format;
>> +	struct v4l2_rect *rect;
>> +	unsigned int sink_pad;
>> +
>> +	/*
>> +	 * Clamp to min/max and then reset crop and compose rectangles to the
>> +	 * newly applied size.
>> +	 */
>> +	clamp_t(unsigned int, fmt->width,
>> +		MALI_C55_MIN_WIDTH, MALI_C55_MAX_WIDTH);
>> +	clamp_t(unsigned int, fmt->height,
>> +		MALI_C55_MIN_HEIGHT, MALI_C55_MAX_HEIGHT);
>> +
>> +	sink_pad = mali_c55_rzr_get_active_sink(state);
>> +	if (sink_pad == MALI_C55_RZR_SINK_PAD) {
>> +		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
>> +
>> +		rect = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD);
>> +		rect->left = 0;
>> +		rect->top = 0;
>> +		rect->width = fmt->width;
>> +		rect->height = fmt->height;
>> +
>> +		rect = v4l2_subdev_state_get_compose(state,
>> +						     MALI_C55_RZR_SINK_PAD);
>> +		rect->left = 0;
>> +		rect->top = 0;
>> +		rect->width = fmt->width;
>> +		rect->height = fmt->height;
>> +	} else {
>> +		/*
>> +		 * Make sure the media bus code is one of the supported
>> +		 * ISP input media bus codes.
>> +		 */
>> +		if (!mali_c55_isp_is_format_supported(fmt->code))
>> +			fmt->code = MALI_C55_DEFAULT_MEDIA_BUS_FMT;
>> +	}
>> +
>> +	*v4l2_subdev_state_get_format(state, sink_pad, 0) = *fmt;
>> +	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD, 0) = *fmt;
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_set_source_fmt(struct v4l2_subdev *sd,
>> +				       struct v4l2_subdev_state *state,
>> +				       struct v4l2_subdev_format *format)
>> +{
>> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
>> +						    sd);
>> +	struct v4l2_mbus_framefmt *fmt = &format->format;
>> +	struct v4l2_mbus_framefmt *sink_fmt;
>> +	struct v4l2_rect *crop, *compose;
>> +	unsigned int sink_pad;
>> +	unsigned int i;
>> +
>> +	sink_pad = mali_c55_rzr_get_active_sink(state);
>> +	sink_fmt = v4l2_subdev_state_get_format(state, sink_pad, 0);
>> +	crop = v4l2_subdev_state_get_crop(state, sink_pad, 0);
>> +	compose = v4l2_subdev_state_get_compose(state, sink_pad, 0);
>> +
>> +	/* FR Bypass pipe. */
>> +
>> +	if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
>> +		/*
>> +		 * Format on the source pad is the same as the one on the
>> +		 * sink pad.
>> +		 */
>> +		fmt->code = sink_fmt->code;
>> +
>> +		/* RAW bypass disables scaling and cropping. */
>> +		crop->top = compose->top = 0;
>> +		crop->left = compose->left = 0;
>> +		fmt->width = crop->width = compose->width = sink_fmt->width;
>> +		fmt->height = crop->height = compose->height = sink_fmt->height;
>> +
>> +		*v4l2_subdev_state_get_format(state,
>> +					      MALI_C55_RZR_SOURCE_PAD) = *fmt;
>> +
>> +		return 0;
>> +	}
>> +
>> +	/* Regular processing pipe. */
>> +
>> +	for (i = 0; i < ARRAY_SIZE(rzr_non_bypass_src_fmts); i++) {
>> +		if (fmt->code == rzr_non_bypass_src_fmts[i])
>> +			break;
>> +	}
>> +
>> +	if (i == ARRAY_SIZE(rzr_non_bypass_src_fmts)) {
>> +		dev_dbg(rzr->mali_c55->dev,
>> +			"Unsupported mbus code 0x%x: using default\n",
>> +			fmt->code);
>> +		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
>> +	}
>> +
>> +	/*
>> +	 * The source pad format size comes directly from the sink pad
>> +	 * compose rectangle.
>> +	 */
>> +	fmt->width = compose->width;
>> +	fmt->height = compose->height;
>> +
>> +	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD) = *fmt;
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_set_fmt(struct v4l2_subdev *sd,
>> +				struct v4l2_subdev_state *state,
>> +				struct v4l2_subdev_format *format)
>> +{
>> +	/*
>> +	 * On sink pads fmt is either fixed for the 'regular' processing
>> +	 * pad or a RAW format or 20-bit wide RGB/YUV format for the FR bypass
>> +	 * pad.
>> +	 *
>> +	 * On source pad sizes are the result of crop+compose on the sink
>> +	 * pad sizes, while the format depends on the active route.
>> +	 */
>> +
>> +	if (format->pad != MALI_C55_RZR_SOURCE_PAD)
>> +		return mali_c55_rzr_set_sink_fmt(sd, state, format);
>> +
>> +	return mali_c55_rzr_set_source_fmt(sd, state, format);
>> +}
>> +
>> +static int mali_c55_rzr_get_selection(struct v4l2_subdev *sd,
>> +				      struct v4l2_subdev_state *state,
>> +				      struct v4l2_subdev_selection *sel)
>> +{
>> +	if (sel->pad != MALI_C55_RZR_SINK_PAD)
>> +		return -EINVAL;
>> +
>> +	if (sel->target != V4L2_SEL_TGT_CROP &&
>> +	    sel->target != V4L2_SEL_TGT_COMPOSE)
>> +		return -EINVAL;
>> +
>> +	sel->r = sel->target == V4L2_SEL_TGT_CROP
>> +	       ? *v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD)
>> +	       : *v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD);
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_set_selection(struct v4l2_subdev *sd,
>> +				      struct v4l2_subdev_state *state,
>> +				      struct v4l2_subdev_selection *sel)
>> +{
>> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
>> +						    sd);
>> +	struct v4l2_mbus_framefmt *source_fmt;
>> +	struct v4l2_mbus_framefmt *sink_fmt;
>> +	struct v4l2_rect *crop, *compose;
>> +
>> +	if (sel->pad != MALI_C55_RZR_SINK_PAD)
>> +		return -EINVAL;
>> +
>> +	if (sel->target != V4L2_SEL_TGT_CROP &&
>> +	    sel->target != V4L2_SEL_TGT_COMPOSE)
>> +		return -EINVAL;
>> +
>> +	source_fmt = v4l2_subdev_state_get_format(state,
>> +						  MALI_C55_RZR_SOURCE_PAD);
>> +	sink_fmt = v4l2_subdev_state_get_format(state, MALI_C55_RZR_SINK_PAD);
>> +	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD);
>> +	compose = v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD);
>> +
>> +	/* RAW bypass disables crop/scaling. */
>> +	if (mali_c55_format_is_raw(source_fmt->code)) {
>> +		crop->top = compose->top = 0;
>> +		crop->left = compose->left = 0;
>> +		crop->width = compose->width = sink_fmt->width;
>> +		crop->height = compose->height = sink_fmt->height;
>> +
>> +		sel->r = sel->target == V4L2_SEL_TGT_CROP ? *crop : *compose;
>> +
>> +		return 0;
>> +	}
>> +
>> +	/* During streaming, it is allowed to only change the crop rectangle. */
>> +	if (rzr->streaming && sel->target != V4L2_SEL_TGT_CROP)
>> +		return -EINVAL;
>> +
>> +	 /*
>> +	  * Update the desired target and then clamp the crop rectangle to the
>> +	  * sink format sizes and the compose size to the crop sizes.
>> +	  */
>> +	if (sel->target == V4L2_SEL_TGT_CROP)
>> +		*crop = sel->r;
>> +	else
>> +		*compose = sel->r;
>> +
>> +	clamp_t(unsigned int, crop->left, 0,  sink_fmt->width);
>> +	clamp_t(unsigned int, crop->top, 0,  sink_fmt->height);
>> +	clamp_t(unsigned int, crop->width, MALI_C55_MIN_WIDTH,
>> +		sink_fmt->width - crop->left);
>> +	clamp_t(unsigned int, crop->height, MALI_C55_MIN_HEIGHT,
>> +		sink_fmt->height - crop->top);
>> +
>> +	if (rzr->streaming) {
>> +		/*
>> +		 * Apply at runtime a crop rectangle on the resizer's sink only
>> +		 * if it doesn't require re-programming the scaler output sizes
>> +		 * as it would require changing the output buffer sizes as well.
>> +		 */
>> +		if (sel->r.width < compose->width ||
>> +		    sel->r.height < compose->height)
>> +			return -EINVAL;
>> +
>> +		*crop = sel->r;
>> +		mali_c55_rzr_program(rzr, state);
>> +
>> +		return 0;
>> +	}
>> +
>> +	compose->left = 0;
>> +	compose->top = 0;
>> +	clamp_t(unsigned int, compose->left, 0,  sink_fmt->width);
>> +	clamp_t(unsigned int, compose->top, 0,  sink_fmt->height);
>> +	clamp_t(unsigned int, compose->width, crop->width / 8, crop->width);
>> +	clamp_t(unsigned int, compose->height, crop->height / 8, crop->height);
>> +
>> +	sel->r = sel->target == V4L2_SEL_TGT_CROP ? *crop : *compose;
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_rzr_set_routing(struct v4l2_subdev *sd,
>> +				    struct v4l2_subdev_state *state,
>> +				    enum v4l2_subdev_format_whence which,
>> +				    struct v4l2_subdev_krouting *routing)
>> +{
>> +	if (which == V4L2_SUBDEV_FORMAT_ACTIVE &&
>> +	    media_entity_is_streaming(&sd->entity))
>> +		return -EBUSY;
>> +
>> +	return __mali_c55_rzr_set_routing(sd, state, routing);
>> +}
>> +
>> +static const struct v4l2_subdev_pad_ops mali_c55_resizer_pad_ops = {
>> +	.enum_mbus_code		= mali_c55_rzr_enum_mbus_code,
>> +	.enum_frame_size	= mali_c55_rzr_enum_frame_size,
>> +	.get_fmt		= v4l2_subdev_get_fmt,
>> +	.set_fmt		= mali_c55_rzr_set_fmt,
>> +	.get_selection		= mali_c55_rzr_get_selection,
>> +	.set_selection		= mali_c55_rzr_set_selection,
>> +	.set_routing		= mali_c55_rzr_set_routing,
>> +};
>> +
>> +void mali_c55_rzr_start_stream(struct mali_c55_resizer *rzr)
>> +{
>> +	struct mali_c55 *mali_c55 = rzr->mali_c55;
>> +	struct v4l2_subdev *sd = &rzr->sd;
>> +	struct v4l2_subdev_state *state;
>> +	unsigned int sink_pad;
>> +
>> +	state = v4l2_subdev_lock_and_get_active_state(sd);
>> +
>> +	sink_pad = mali_c55_rzr_get_active_sink(state);
>> +	if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
>> +		/* Bypass FR pipe processing if the bypass route is active. */
>> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
>> +				     MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK,
>> +				     MALI_C55_ISP_RAW_BYPASS_RAW_FR_BYPASS);
>> +		goto unlock_state;
>> +	}
>> +
>> +	/* Disable bypass and use regular processing. */
>> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
>> +			     MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK, 0);
>> +	mali_c55_rzr_program(rzr, state);
>> +
>> +unlock_state:
>> +	rzr->streaming = true;
>> +	v4l2_subdev_unlock_state(state);
>> +}
>> +
>> +void mali_c55_rzr_stop_stream(struct mali_c55_resizer *rzr)
>> +{
>> +	struct v4l2_subdev *sd = &rzr->sd;
>> +	struct v4l2_subdev_state *state;
>> +
>> +	state = v4l2_subdev_lock_and_get_active_state(sd);
>> +	rzr->streaming = false;
>> +	v4l2_subdev_unlock_state(state);
>> +}
>> +
>> +static const struct v4l2_subdev_ops mali_c55_resizer_ops = {
>> +	.pad	= &mali_c55_resizer_pad_ops,
>> +};
>> +
>> +static int mali_c55_rzr_init_state(struct v4l2_subdev *sd,
>> +				   struct v4l2_subdev_state *state)
>> +{
>> +	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
>> +						    sd);
>> +	struct v4l2_subdev_krouting routing = { };
>> +	struct v4l2_subdev_route *routes;
>> +	unsigned int i;
>> +	int ret;
>> +
>> +	routes = kcalloc(rzr->num_routes, sizeof(*routes), GFP_KERNEL);
>> +	if (!routes)
>> +		return -ENOMEM;
>> +
>> +	for (i = 0; i < rzr->num_routes; ++i) {
>> +		struct v4l2_subdev_route *route = &routes[i];
>> +
>> +		route->sink_pad = i
>> +				? MALI_C55_RZR_SINK_BYPASS_PAD
>> +				: MALI_C55_RZR_SINK_PAD;
>> +		route->source_pad = MALI_C55_RZR_SOURCE_PAD;
>> +		if (route->sink_pad != MALI_C55_RZR_SINK_BYPASS_PAD)
>> +			route->flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE;
>> +	}
>> +
>> +	routing.num_routes = rzr->num_routes;
>> +	routing.routes = routes;
>> +
>> +	ret = __mali_c55_rzr_set_routing(sd, state, &routing);
>> +	kfree(routes);
>> +
>> +	return ret;
>> +}
>> +
>> +static const struct v4l2_subdev_internal_ops mali_c55_resizer_internal_ops = {
>> +	.init_state = mali_c55_rzr_init_state,
>> +};
>> +
>> +static void mali_c55_resizer_program_coefficients(struct mali_c55 *mali_c55,
>> +						  unsigned int index)
>> +{
>> +	unsigned int scaler_filt_coefmem_addrs[][2] = {
> This should be const.
>
>> +		[MALI_C55_RZR_FR] = {
>> +			0x034A8, /* hfilt */
>> +			0x044A8  /* vfilt */
>> +		},
>> +		[MALI_C55_RZR_DS] = {
>> +			0x014A8, /* hfilt */
>> +			0x024A8  /* vfilt */
>> +		},
>> +	};
>> +	unsigned int haddr = scaler_filt_coefmem_addrs[index][0];
>> +	unsigned int vaddr = scaler_filt_coefmem_addrs[index][1];
>> +	unsigned int i, j;
>> +
>> +	for (i = 0; i < MALI_C55_RESIZER_COEFS_NUM_BANKS; i++) {
>> +		for (j = 0; j < MALI_C55_RESIZER_COEFS_NUM_ENTRIES; j++) {
>> +			mali_c55_write(mali_c55, haddr,
>> +				mali_c55_scaler_h_filter_coefficients[i][j]);
>> +			mali_c55_write(mali_c55, vaddr,
>> +				mali_c55_scaler_v_filter_coefficients[i][j]);
>> +
>> +			haddr += 4;
>> +			vaddr += 4;
> sizeof(u32) ?
>
> Up to you.


I think I'll keep it if it's all the same to you

>
>> +		}
>> +	}
>> +}
>> +
>> +int mali_c55_register_resizers(struct mali_c55 *mali_c55)
>> +{
>> +	unsigned int i;
>> +	int ret;
>> +
>> +	for (i = 0; i < MALI_C55_NUM_RZRS; ++i) {
>> +		struct mali_c55_resizer *rzr = &mali_c55->resizers[i];
>> +		struct v4l2_subdev *sd = &rzr->sd;
>> +		unsigned int num_pads = MALI_C55_RZR_NUM_PADS;
>> +
>> +		rzr->id = i;
>> +		rzr->streaming = false;
>> +
>> +		if (rzr->id == MALI_C55_RZR_FR)
>> +			rzr->cap_dev = &mali_c55->cap_devs[MALI_C55_CAP_DEV_FR];
>> +		else
>> +			rzr->cap_dev = &mali_c55->cap_devs[MALI_C55_CAP_DEV_DS];
>> +
>> +		mali_c55_resizer_program_coefficients(mali_c55, i);
>> +
>> +		v4l2_subdev_init(sd, &mali_c55_resizer_ops);
>> +		sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE
>> +			  | V4L2_SUBDEV_FL_STREAMS;
> "|" should be aligned with beginning of the rvalue, i.e. "V" of
> V4L2_SUBDEV_FL_HAS_DEVNODE.
>
>> +		sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
>> +		sd->owner = THIS_MODULE;
>> +		sd->internal_ops = &mali_c55_resizer_internal_ops;
>> +		snprintf(sd->name, ARRAY_SIZE(sd->name), "%s %s",
>> +			 MALI_C55_DRIVER_NAME, mali_c55_resizer_names[i]);
>> +
>> +		rzr->pads[MALI_C55_RZR_SINK_PAD].flags = MEDIA_PAD_FL_SINK;
>> +		rzr->pads[MALI_C55_RZR_SOURCE_PAD].flags = MEDIA_PAD_FL_SOURCE;
>> +
>> +		/* Only the FR pipe has a bypass pad. */
>> +		if (rzr->id == MALI_C55_RZR_FR) {
>> +			rzr->pads[MALI_C55_RZR_SINK_BYPASS_PAD].flags =
>> +							MEDIA_PAD_FL_SINK;
>> +			rzr->num_routes = 2;
>> +		} else {
>> +			num_pads -= 1;
>> +			rzr->num_routes = 1;
>> +		}
>> +
>> +		ret = media_entity_pads_init(&sd->entity, num_pads, rzr->pads);
>> +		if (ret)
>> +			return ret;
>> +
>> +		ret = v4l2_subdev_init_finalize(sd);
>> +		if (ret)
>> +			goto err_cleanup;
>> +
>> +		ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
>> +		if (ret)
>> +			goto err_cleanup;
>> +
>> +		rzr->mali_c55 = mali_c55;
>> +	}
>> +
>> +	return 0;
>> +
>> +err_cleanup:
>> +	for (; i >= 0; --i) {
>> +		struct mali_c55_resizer *rzr = &mali_c55->resizers[i];
>> +		struct v4l2_subdev *sd = &rzr->sd;
>> +
>> +		v4l2_subdev_cleanup(sd);
>> +		media_entity_cleanup(&sd->entity);
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>> +void mali_c55_unregister_resizers(struct mali_c55 *mali_c55)
>> +{
>> +	unsigned int i;
>> +
>> +	for (i = 0; i < MALI_C55_NUM_RZRS; i++) {
>> +		struct mali_c55_resizer *resizer = &mali_c55->resizers[i];
>> +
>> +		if (!resizer->mali_c55)
>> +			continue;
>> +
>> +		v4l2_device_unregister_subdev(&resizer->sd);
>> +		v4l2_subdev_cleanup(&resizer->sd);
>> +		media_entity_cleanup(&resizer->sd.entity);
>> +	}
>> +}
>> diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c b/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
>> new file mode 100644
>> index 000000000000..042851a4b42d
>> --- /dev/null
>> +++ b/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
>> @@ -0,0 +1,424 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * ARM Mali-C55 ISP Driver - Test pattern generator
>> + *
>> + * Copyright (C) 2024 Ideas on Board Oy
>> + */
>> +
>> +#include <linux/minmax.h>
>> +#include <linux/string.h>
>> +
>> +#include <media/media-entity.h>
>> +#include <media/v4l2-ctrls.h>
>> +#include <media/v4l2-subdev.h>
>> +
>> +#include "mali-c55-common.h"
>> +#include "mali-c55-registers.h"
>> +
>> +#define MALI_C55_TPG_SRC_PAD		0
>> +#define MALI_C55_TPG_FIXED_HBLANK	0x20
>> +#define MALI_C55_TPG_MAX_VBLANK		0xFFFF
>> +#define MALI_C55_TPG_PIXEL_RATE		100000000
>> +
>> +static const char * const mali_c55_tpg_test_pattern_menu[] = {
>> +	"Flat field",
>> +	"Horizontal gradient",
>> +	"Vertical gradient",
>> +	"Vertical bars",
>> +	"Arbitrary rectangle",
>> +	"White frame on black field"
>> +};
>> +
>> +static const u32 mali_c55_tpg_mbus_codes[] = {
>> +	MEDIA_BUS_FMT_SRGGB16_1X16,
>> +	/*
>> +	 * This is a lie. In RGB mode the Test Pattern Generator actually output
>> +	 * 16-bits-per-colour data. However, RGB data follows one of the Bypass
>> +	 * paths which has a 12-bit limit at the insertion point, meaning it
>> +	 * would be truncated there to match the internal 12-bit format that
>> +	 * would be output from the debayering block. The same is true of RGB
>> +	 * data output by a sensor and streamed to the ISP's input port, however
>> +	 * in that case the ISP's input port requires that data be converted to
>> +	 * a 20-bit MSB aligned format. Given:
>> +	 *
>> +	 *	1. Our chosen topology represents the TPG as a subdevice
>> +	 *	   linked to the ISP's input port.
>> +	 *	2. We need to restrict the ISP's sink pad to only accepting that
>> +	 *	   20-bit RGB format from sensors / CSI-2 receivers.
>> +	 *	3. All the data ultimately ends up in the same format anyway and
>> +	 *	   these data from the TPG are purely internal to the ISP
>> +	 *
>> +	 * It seems best to reduce the programming complexity by simply
>> +	 * pretending that the TPG outputs data in the same format that the ISP
>> +	 * input port requires, even though it doesn't really.
>> +	 */
>> +	MEDIA_BUS_FMT_RGB202020_1X60,
>> +};
>> +
>> +static void __mali_c55_tpg_calc_vblank(struct v4l2_mbus_framefmt *format,
>> +				       int *def_vblank, int *min_vblank)
>> +{
>> +	unsigned int hts;
>> +	int tgt_fps;
>> +	int vblank;
>> +
>> +	hts = format->width + MALI_C55_TPG_FIXED_HBLANK;
>> +
>> +	/*
>> +	 * The ISP has minimum vertical blanking requirements that must be
>> +	 * adhered to by the TPG. The minimum is a function of the Iridix blocks
>> +	 * clocking requirements and the width of the image and horizontal
>> +	 * blanking, but if we assume the worst case iVariance and sVariance
>> +	 * values then it boils down to the below.
>> +	 */
>> +	*min_vblank = 15 + (120500 / hts);
>> +
>> +	/*
>> +	 * We need to set a sensible default vblank for whatever format height
>> +	 * we happen to be given from set_fmt(). This function just targets
>> +	 * an even multiple of 15fps. If we can't get 15fps, let's target 5fps.
>> +	 * If we can't get 5fps we'll take whatever the minimum vblank gives us.
>> +	 */
>> +	tgt_fps = MALI_C55_TPG_PIXEL_RATE / hts / (format->height + *min_vblank);
>> +
>> +	if (tgt_fps < 5)
>> +		vblank = *min_vblank;
>> +	else
>> +		vblank = MALI_C55_TPG_PIXEL_RATE / hts
>> +		       / max(rounddown(tgt_fps, 15), 5);
>> +
>> +	*def_vblank = ALIGN_DOWN(vblank, 2) - format->height;
>> +}
>> +
>> +static int mali_c55_tpg_s_ctrl(struct v4l2_ctrl *ctrl)
>> +{
>> +	struct mali_c55_tpg *tpg = container_of(ctrl->handler,
>> +						struct mali_c55_tpg,
>> +						ctrls.handler);
>> +	struct mali_c55 *mali_c55 = container_of(tpg, struct mali_c55, tpg);
>> +
>> +	switch (ctrl->id) {
>> +	case V4L2_CID_TEST_PATTERN:
>> +		mali_c55_write(mali_c55, MALI_C55_REG_TEST_GEN_CH0_PATTERN_TYPE,
>> +			       ctrl->val);
>> +		break;
>> +	case V4L2_CID_VBLANK:
>> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_BLANKING,
>> +				     MALI_C55_REG_VBLANK_MASK, ctrl->val);
>> +		break;
>> +	default:
>> +		dev_err(mali_c55->dev, "invalid V4L2 control ID\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct v4l2_ctrl_ops mali_c55_tpg_ctrl_ops = {
>> +	.s_ctrl = &mali_c55_tpg_s_ctrl,
>> +};
>> +
>> +static void mali_c55_tpg_configure(struct mali_c55 *mali_c55,
>> +				   struct v4l2_subdev *sd)
>> +{
>> +	struct v4l2_subdev_state *state;
>> +	struct v4l2_mbus_framefmt *fmt;
>> +
>> +	/*
>> +	 * hblank needs setting, but is a read-only control and thus won't be
>> +	 * called during __v4l2_ctrl_handler_setup(). Do it here instead.
>> +	 */
>> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_BLANKING,
>> +			     MALI_C55_REG_HBLANK_MASK,
>> +			     MALI_C55_TPG_FIXED_HBLANK);
>> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
>> +			     MALI_C55_REG_GEN_VIDEO_MULTI_MASK, 0x01);
>> +
>> +	state = v4l2_subdev_lock_and_get_active_state(sd);
>> +	fmt = v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD);
>> +
>> +	mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
>> +			     MALI_C55_TEST_PATTERN_RGB_MASK,
>> +			     fmt->code == MEDIA_BUS_FMT_RGB202020_1X60 ?
>> +					  0x01 : 0x0);
>> +
>> +	v4l2_subdev_unlock_state(state);
>> +}
>> +
>> +static int mali_c55_tpg_s_stream(struct v4l2_subdev *sd, int enable)
>> +{
>> +	struct mali_c55_tpg *tpg = container_of(sd, struct mali_c55_tpg, sd);
>> +	struct mali_c55 *mali_c55 = container_of(tpg, struct mali_c55, tpg);
>> +
>> +	if (!enable) {
>> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
>> +				     MALI_C55_TEST_PATTERN_ON_OFF, 0x00);
>> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
>> +				     MALI_C55_REG_GEN_VIDEO_ON_MASK, 0x00);
>> +	} else {
>> +		/*
>> +		 * One might reasonably expect the framesize to be set here
>> +		 * given it's configurable in .set_fmt(), but it's done in the
>> +		 * ISP subdevice's .s_stream() instead, as the same register is
>> +		 * also used to indicate the size of the data coming from the
>> +		 * sensor.
>> +		 */
>> +		mali_c55_tpg_configure(mali_c55, sd);
>> +		__v4l2_ctrl_handler_setup(sd->ctrl_handler);
>> +
>> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
>> +				     MALI_C55_TEST_PATTERN_ON_OFF,
>> +				     MALI_C55_TEST_PATTERN_ON_OFF);
>> +		mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
>> +				     MALI_C55_REG_GEN_VIDEO_ON_MASK,
>> +				     MALI_C55_REG_GEN_VIDEO_ON_MASK);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct v4l2_subdev_video_ops mali_c55_tpg_video_ops = {
>> +	.s_stream = &mali_c55_tpg_s_stream,
>> +};
>> +
>> +static int mali_c55_tpg_enum_mbus_code(struct v4l2_subdev *sd,
>> +				       struct v4l2_subdev_state *state,
>> +				       struct v4l2_subdev_mbus_code_enum *code)
>> +{
>> +	if (code->pad >= sd->entity.num_pads)
>> +		return -EINVAL;
> This check is done by the framework, you can drop it here.
>
>> +
>> +	if (code->index >= ARRAY_SIZE(mali_c55_tpg_mbus_codes))
>> +		return -EINVAL;
>> +
>> +	code->code = mali_c55_tpg_mbus_codes[code->index];
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_tpg_enum_frame_size(struct v4l2_subdev *sd,
>> +					struct v4l2_subdev_state *state,
>> +					struct v4l2_subdev_frame_size_enum *fse)
>> +{
>> +	if (fse->index > 0 || fse->pad > sd->entity.num_pads)
>> +		return -EINVAL;
>> +
>> +	fse->min_width = MALI_C55_MIN_WIDTH;
>> +	fse->max_width = MALI_C55_MAX_WIDTH;
>> +	fse->min_height = MALI_C55_MIN_HEIGHT;
>> +	fse->max_height = MALI_C55_MAX_HEIGHT;
>> +
>> +	return 0;
>> +}
>> +
>> +static int mali_c55_tpg_set_fmt(struct v4l2_subdev *sd,
>> +				struct v4l2_subdev_state *state,
>> +				struct v4l2_subdev_format *format)
>> +{
>> +	struct mali_c55_tpg *tpg = container_of(sd, struct mali_c55_tpg, sd);
>> +	struct v4l2_mbus_framefmt *fmt = &format->format;
>> +	int vblank_def, vblank_min;
>> +	unsigned int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(mali_c55_tpg_mbus_codes); i++) {
>> +		if (fmt->code == mali_c55_tpg_mbus_codes[i])
>> +			break;
>> +	}
>> +
>> +	if (i == ARRAY_SIZE(mali_c55_tpg_mbus_codes))
>> +		fmt->code = MEDIA_BUS_FMT_SRGGB16_1X16;
>> +
>> +	/*
>> +	 * The TPG says that the test frame timing generation logic expects a
>> +	 * minimum framesize of 4x4 pixels, but given the rest of the ISP can't
>> +	 * handle anything smaller than 128x128 it seems pointless to allow a
>> +	 * smaller frame.
>> +	 */
>> +	clamp_t(unsigned int, fmt->width, MALI_C55_MIN_WIDTH,
>> +		MALI_C55_MAX_WIDTH);
>> +	clamp_t(unsigned int, fmt->height, MALI_C55_MIN_HEIGHT,
>> +		MALI_C55_MAX_HEIGHT);
>> +
>> +	*v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD) = *fmt;
>> +
> Shouldn't the controls below only be changed for the active format?


Yes! Thank you

>
>> +	__mali_c55_tpg_calc_vblank(fmt, &vblank_def, &vblank_min);
>> +	__v4l2_ctrl_modify_range(tpg->ctrls.vblank, vblank_min,
>> +				 MALI_C55_TPG_MAX_VBLANK, 1, vblank_def);
>> +	__v4l2_ctrl_s_ctrl(tpg->ctrls.vblank, vblank_def);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct v4l2_subdev_pad_ops mali_c55_tpg_pad_ops = {
>> +	.enum_mbus_code		= mali_c55_tpg_enum_mbus_code,
>> +	.enum_frame_size	= mali_c55_tpg_enum_frame_size,
>> +	.get_fmt		= v4l2_subdev_get_fmt,
>> +	.set_fmt		= mali_c55_tpg_set_fmt,
>> +};
>> +
>> +static const struct v4l2_subdev_ops mali_c55_tpg_ops = {
>> +	.video	= &mali_c55_tpg_video_ops,
>> +	.pad	= &mali_c55_tpg_pad_ops,
>> +};
>> +
>> +static int mali_c55_tpg_init_state(struct v4l2_subdev *sd,
>> +				   struct v4l2_subdev_state *sd_state)
>> +{
>> +	struct v4l2_mbus_framefmt *fmt;
>> +
>> +	fmt = v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);
> Can be assigned in the declaration.


How would you make it fit that way?

>
>> +
>> +	fmt->width = MALI_C55_DEFAULT_WIDTH;
>> +	fmt->height = MALI_C55_DEFAULT_HEIGHT;
>> +	fmt->field = V4L2_FIELD_NONE;
>> +	fmt->code = MEDIA_BUS_FMT_SRGGB16_1X16;
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct v4l2_subdev_internal_ops mali_c55_tpg_internal_ops = {
>> +	.init_state = mali_c55_tpg_init_state,
>> +};
>> +
>> +static int mali_c55_tpg_init_controls(struct mali_c55 *mali_c55)
>> +{
>> +	struct mali_c55_tpg_ctrls *ctrls = &mali_c55->tpg.ctrls;
>> +	struct v4l2_subdev *sd = &mali_c55->tpg.sd;
>> +	struct v4l2_mbus_framefmt *format;
>> +	struct v4l2_subdev_state *state;
>> +	int vblank_def, vblank_min;
>> +	int ret;
>> +
>> +	state = v4l2_subdev_lock_and_get_active_state(sd);
>> +	format = v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD);
>> +
>> +	ret = v4l2_ctrl_handler_init(&ctrls->handler, 1);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ctrls->test_pattern = v4l2_ctrl_new_std_menu_items(&ctrls->handler,
>> +				&mali_c55_tpg_ctrl_ops, V4L2_CID_TEST_PATTERN,
>> +				ARRAY_SIZE(mali_c55_tpg_test_pattern_menu) - 1,
>> +				0, 3, mali_c55_tpg_test_pattern_menu);
>> +
>> +	/*
>> +	 * We fix hblank at the minimum allowed value and control framerate
>> +	 * solely through the vblank control.
>> +	 */
>> +	ctrls->hblank = v4l2_ctrl_new_std(&ctrls->handler,
>> +				&mali_c55_tpg_ctrl_ops,
>> +				V4L2_CID_HBLANK, MALI_C55_TPG_FIXED_HBLANK,
>> +				MALI_C55_TPG_FIXED_HBLANK, 1,
>> +				MALI_C55_TPG_FIXED_HBLANK);
>> +	if (ctrls->hblank)
>> +		ctrls->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
>> +
>> +	__mali_c55_tpg_calc_vblank(format, &vblank_def, &vblank_min);
>> +	ctrls->vblank = v4l2_ctrl_new_std(&ctrls->handler,
>> +					  &mali_c55_tpg_ctrl_ops,
>> +					  V4L2_CID_VBLANK, vblank_min,
>> +					  MALI_C55_TPG_MAX_VBLANK, 1,
>> +					  vblank_def);
>> +
>> +	if (ctrls->handler.error) {
>> +		dev_err(mali_c55->dev, "Error during v4l2 controls init\n");
>> +		ret = ctrls->handler.error;
>> +		goto err_free_handler;
>> +	}
>> +
>> +	ctrls->handler.lock = &mali_c55->tpg.lock;
>> +	mali_c55->tpg.sd.ctrl_handler = &ctrls->handler;
>> +
>> +	v4l2_subdev_unlock_state(state);
>> +
>> +	return 0;
>> +
>> +err_free_handler:
>> +	v4l2_ctrl_handler_free(&ctrls->handler);
>> +err_unlock:
>> +	v4l2_subdev_unlock_state(state);
>> +	return ret;
>> +}
>> +
>> +int mali_c55_register_tpg(struct mali_c55 *mali_c55)
>> +{
>> +	struct mali_c55_tpg *tpg = &mali_c55->tpg;
>> +	struct v4l2_subdev *sd = &tpg->sd;
>> +	struct media_pad *pad = &tpg->pad;
>> +	int ret;
>> +
>> +	mutex_init(&tpg->lock);
>> +
>> +	v4l2_subdev_init(sd, &mali_c55_tpg_ops);
>> +	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
>> +	sd->entity.function = MEDIA_ENT_F_CAM_SENSOR;
>> +	sd->owner = THIS_MODULE;
>> +	sd->internal_ops = &mali_c55_tpg_internal_ops;
>> +	strscpy(sd->name, MALI_C55_DRIVER_NAME " tpg", sizeof(sd->name));
>> +
>> +	pad->flags = MEDIA_PAD_FL_SOURCE | MEDIA_PAD_FL_MUST_CONNECT;
>> +	ret = media_entity_pads_init(&sd->entity, 1, pad);
>> +	if (ret) {
>> +		dev_err(mali_c55->dev,
>> +			"Failed to initialize media entity pads\n");
>> +		goto err_destroy_mutex;
>> +	}
>> +
>> +	ret = v4l2_subdev_init_finalize(sd);
>> +	if (ret)
>> +		goto err_cleanup_media_entity;
>> +
>> +	ret = mali_c55_tpg_init_controls(mali_c55);
>> +	if (ret) {
>> +		dev_err(mali_c55->dev,
>> +			"Error initialising controls\n");
>> +		goto err_cleanup_subdev;
>> +	}
>> +
>> +	ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
>> +	if (ret) {
>> +		dev_err(mali_c55->dev, "Failed to register tpg subdev\n");
>> +		goto err_free_ctrl_handler;
>> +	}
>> +
>> +	/*
>> +	 * By default the colour settings lead to a very dim image that is
>> +	 * nearly indistinguishable from black on some monitor settings. Ramp
>> +	 * them up a bit so the image is brighter.
>> +	 */
>> +	mali_c55_write(mali_c55, MALI_C55_REG_TPG_R_BACKGROUND,
>> +		       MALI_C55_TPG_BACKGROUND_MAX);
>> +	mali_c55_write(mali_c55, MALI_C55_REG_TPG_G_BACKGROUND,
>> +		       MALI_C55_TPG_BACKGROUND_MAX);
>> +	mali_c55_write(mali_c55, MALI_C55_REG_TPG_B_BACKGROUND,
>> +		       MALI_C55_TPG_BACKGROUND_MAX);
>> +
>> +	tpg->mali_c55 = mali_c55;
>> +
>> +	return 0;
>> +
>> +err_free_ctrl_handler:
>> +	v4l2_ctrl_handler_free(&tpg->ctrls.handler);
>> +err_cleanup_subdev:
>> +	v4l2_subdev_cleanup(sd);
>> +err_cleanup_media_entity:
>> +	media_entity_cleanup(&sd->entity);
>> +err_destroy_mutex:
>> +	mutex_destroy(&tpg->lock);
>> +
>> +	return ret;
>> +}
>> +
>> +void mali_c55_unregister_tpg(struct mali_c55 *mali_c55)
>> +{
>> +	struct mali_c55_tpg *tpg = &mali_c55->tpg;
>> +
>> +	if (!tpg->mali_c55)
>> +		return;
>> +
>> +	v4l2_device_unregister_subdev(&tpg->sd);
>> +	v4l2_subdev_cleanup(&tpg->sd);
>> +	media_entity_cleanup(&tpg->sd.entity);
>> +	v4l2_ctrl_handler_free(&tpg->ctrls.handler);
>> +	mutex_destroy(&tpg->lock);
>> +}

Dan Scally May 23, 2024, 2:27 p.m. UTC | #6

Hi Sakari - sorry, one part I missed...

On 23/05/2024 09:03, Sakari Ailus wrote:
>> +
>> +int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable)
> Have you considered {enable,disable}_streams? All new drivers should use
> these instead of s_stream() now.


Although named s_stream this is actually a purely internal function - it's not exposed as part of 
the subdev video ops. The resizer subdevices similarly don't expose an .s_stream() operation, 
they're simply started in the callpath of mali_c55_vb2_start_streaming(). I'll split the stop 
functionality into mali_c55_isp_stop_stream() and rename this mali_c55_isp_start_stream() to make 
that less confusing.


The TPG subdevice on the other hand does expose an .s_stream() operation, since the intention was to 
model it exactly like a connected external subdevice. I can switch to the .enable_streams() 
operation there.

>
>> +{
>> +	struct mali_c55 *mali_c55 = isp->mali_c55;
>> +	struct media_pad *source_pad;
>> +	struct media_pad *sink_pad;
>> +	int ret;
>> +
>> +	if (!enable) {
>> +		if (isp->source)
>> +			v4l2_subdev_call(isp->source, video, s_stream, false);
>> +		isp->source = NULL;
>> +
>> +		mali_c55_isp_stop(mali_c55);
>> +
>> +		return 0;
>> +	}
>> +
>> +	sink_pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
>> +	source_pad = media_pad_remote_pad_unique(sink_pad);
>> +	if (IS_ERR(source_pad)) {
>> +		dev_err(mali_c55->dev, "Failed to get source for ISP\n");
>> +		return PTR_ERR(source_pad);
>> +	}
>> +
>> +	isp->source = media_entity_to_v4l2_subdev(source_pad->entity);
>> +
>> +	isp->frame_sequence = 0;
>> +	ret = mali_c55_isp_start(mali_c55);
>> +	if (ret) {
>> +		dev_err(mali_c55->dev, "Failed to start ISP\n");
>> +		isp->source = NULL;
>> +		return ret;
>> +	}
>> +
>> +	ret = v4l2_subdev_call(isp->source, video, s_stream, true);
>> +	if (ret) {
>> +		dev_err(mali_c55->dev, "Failed to start ISP source\n");
>> +		mali_c55_isp_stop(mali_c55);
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +

Sakari Ailus May 23, 2024, 5:53 p.m. UTC | #7

Hi Dan,

On Thu, May 23, 2024 at 02:44:06PM +0100, Dan Scally wrote:
> Hi Sakari - thanks for the review. Snipping some bits for which I have no comment...
> 
> On 23/05/2024 09:03, Sakari Ailus wrote:
> 
> <snip>
> > > +
> > > +static unsigned int mali_c55_calculate_bank_num(struct mali_c55 *mali_c55,
> > > +						unsigned int crop,
> > > +						unsigned int scale)
> > > +{
> > > +	unsigned int tmp;
> > > +	unsigned int i;
> > > +
> > > +	tmp = (scale * 1000) / crop;
> > This looks like something that can overflow. Can it?
> 
> 
> Shouldn't be able to; maximum scale width is 8192.

Ok.

1000U in that case?

> > > +	for (i = 0; i < MALI_C55_RESIZER_COEFS_NUM_BANKS; i++) {
> > > +		for (j = 0; j < MALI_C55_RESIZER_COEFS_NUM_ENTRIES; j++) {
> > > +			mali_c55_write(mali_c55, haddr,
> > > +				mali_c55_scaler_h_filter_coefficients[i][j]);
> > > +			mali_c55_write(mali_c55, vaddr,
> > > +				mali_c55_scaler_v_filter_coefficients[i][j]);
> > > +
> > > +			haddr += 4;
> > > +			vaddr += 4;
> > sizeof(u32) ?
> > 
> > Up to you.
> 
> 
> I think I'll keep it if it's all the same to you

Well, not the same but I'll let you decide. :-)

...

> > > +static int mali_c55_tpg_init_state(struct v4l2_subdev *sd,
> > > +				   struct v4l2_subdev_state *sd_state)
> > > +{
> > > +	struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +	fmt = v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);
> > Can be assigned in the declaration.
> 
> 
> How would you make it fit that way?

	struct v4l2_mbus_framefmt *fmt =
		v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);

Sakari Ailus May 23, 2024, 8:57 p.m. UTC | #8

Hi Dan,

On Thu, May 23, 2024 at 03:27:36PM +0100, Dan Scally wrote:
> Hi Sakari - sorry, one part I missed...
> 
> On 23/05/2024 09:03, Sakari Ailus wrote:
> > > +
> > > +int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable)
> > Have you considered {enable,disable}_streams? All new drivers should use
> > these instead of s_stream() now.
> 
> 
> Although named s_stream this is actually a purely internal function - it's
> not exposed as part of the subdev video ops. The resizer subdevices
> similarly don't expose an .s_stream() operation, they're simply started in
> the callpath of mali_c55_vb2_start_streaming(). I'll split the stop
> functionality into mali_c55_isp_stop_stream() and rename this
> mali_c55_isp_start_stream() to make that less confusing.

Ack. But this might require some rework, depending on based on what
streaming is actually started. I'm referring to the discussion elsewhere
in the same thread.

> 
> 
> The TPG subdevice on the other hand does expose an .s_stream() operation,
> since the intention was to model it exactly like a connected external
> subdevice. I can switch to the .enable_streams() operation there.

Sounds good.

> 
> > 
> > > +{
> > > +	struct mali_c55 *mali_c55 = isp->mali_c55;
> > > +	struct media_pad *source_pad;
> > > +	struct media_pad *sink_pad;
> > > +	int ret;
> > > +
> > > +	if (!enable) {
> > > +		if (isp->source)
> > > +			v4l2_subdev_call(isp->source, video, s_stream, false);

This call could be v4l2_subdev_disable_streams().

> > > +		isp->source = NULL;
> > > +
> > > +		mali_c55_isp_stop(mali_c55);
> > > +
> > > +		return 0;
> > > +	}
> > > +
> > > +	sink_pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
> > > +	source_pad = media_pad_remote_pad_unique(sink_pad);
> > > +	if (IS_ERR(source_pad)) {
> > > +		dev_err(mali_c55->dev, "Failed to get source for ISP\n");
> > > +		return PTR_ERR(source_pad);
> > > +	}
> > > +
> > > +	isp->source = media_entity_to_v4l2_subdev(source_pad->entity);
> > > +
> > > +	isp->frame_sequence = 0;
> > > +	ret = mali_c55_isp_start(mali_c55);
> > > +	if (ret) {
> > > +		dev_err(mali_c55->dev, "Failed to start ISP\n");
> > > +		isp->source = NULL;
> > > +		return ret;
> > > +	}
> > > +
> > > +	ret = v4l2_subdev_call(isp->source, video, s_stream, true);

And this could be v4l2_subdev_enable_streams() as well.

> > > +	if (ret) {
> > > +		dev_err(mali_c55->dev, "Failed to start ISP source\n");
> > > +		mali_c55_isp_stop(mali_c55);
> > > +		return ret;
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +

Sakari Ailus May 23, 2024, 9:01 p.m. UTC | #9

Hi Dan,

On Thu, May 23, 2024 at 12:22:45PM +0100, Dan Scally wrote:
> Hello
> 
> On 23/05/2024 10:49, Laurent Pinchart wrote:
> > On Thu, May 23, 2024 at 11:48:02AM +0200, Jacopo Mondi wrote:
> > > On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
> > > > Hi Daniel,
> > > [snip]
> > > 
> > > > > +
> > > > > +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
> > > > > +{
> > > > > +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> > > > > +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> > > > > +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> > > > > +	struct mali_c55_isp *isp = &mali_c55->isp;
> > > > > +	int ret;
> > > > > +
> > > > > +	guard(mutex)(&isp->lock);
> > > > > +
> > > > > +	ret = pm_runtime_resume_and_get(mali_c55->dev);
> > > > > +	if (ret)
> > > > > +		return ret;
> > > > > +
> > > > > +	ret = video_device_pipeline_start(&cap_dev->vdev,
> > > > > +					  &cap_dev->mali_c55->pipe);
> > > > > +	if (ret) {
> > > > > +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
> > > > > +			mali_c55_cap_dev_to_name(cap_dev));
> > > > > +		goto err_pm_put;
> > > > > +	}
> > > > > +
> > > > > +	mali_c55_cap_dev_stream_enable(cap_dev);
> > > > > +	mali_c55_rzr_start_stream(rzr);
> > > > > +
> > > > > +	/*
> > > > > +	 * We only start the ISP if we're the only capture device that's
> > > > > +	 * streaming. Otherwise, it'll already be active.
> > > > > +	 */
> > > > > +	if (mali_c55->pipe.start_count == 1) {
> > > > Do you start streaming on the sensor when the first video node does?
> > > > 
> > > > This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
> > > > streaming on the sensor once all video nodes of the pipeline have been
> > > > started.
> > > How would you ever know which nodes will be started ?
> > That can be done with link setup. Any video device that has an active
> > link to the ISP would need to be started.
> 
> 
> So if you don't want to stream data from one of the two capture nodes, you'd
> need to disable the link between it and the resizer? That seems quite
> clunky. Does it matter if one of them starts a frame or two later? As
> opposed to both of them starting in sync a frame or two later?

Video frames on a given queue are lost due to the driver implementation.
I might consider that to be a driver bug.

It's also true that some use cases could also benefit from the behaviour
but on regular CSI-2 receivers that's probably quite rare. We'd need
additional APIs to be able to convey the desired behaviour to the drivers.

Dan Scally May 24, 2024, 8:37 a.m. UTC | #10

Good morning Sakari

On 23/05/2024 22:01, Sakari Ailus wrote:
> Hi Dan,
>
> On Thu, May 23, 2024 at 12:22:45PM +0100, Dan Scally wrote:
>> Hello
>>
>> On 23/05/2024 10:49, Laurent Pinchart wrote:
>>> On Thu, May 23, 2024 at 11:48:02AM +0200, Jacopo Mondi wrote:
>>>> On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
>>>>> Hi Daniel,
>>>> [snip]
>>>>
>>>>>> +
>>>>>> +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
>>>>>> +{
>>>>>> +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
>>>>>> +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
>>>>>> +	struct mali_c55_resizer *rzr = cap_dev->rzr;
>>>>>> +	struct mali_c55_isp *isp = &mali_c55->isp;
>>>>>> +	int ret;
>>>>>> +
>>>>>> +	guard(mutex)(&isp->lock);
>>>>>> +
>>>>>> +	ret = pm_runtime_resume_and_get(mali_c55->dev);
>>>>>> +	if (ret)
>>>>>> +		return ret;
>>>>>> +
>>>>>> +	ret = video_device_pipeline_start(&cap_dev->vdev,
>>>>>> +					  &cap_dev->mali_c55->pipe);
>>>>>> +	if (ret) {
>>>>>> +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
>>>>>> +			mali_c55_cap_dev_to_name(cap_dev));
>>>>>> +		goto err_pm_put;
>>>>>> +	}
>>>>>> +
>>>>>> +	mali_c55_cap_dev_stream_enable(cap_dev);
>>>>>> +	mali_c55_rzr_start_stream(rzr);
>>>>>> +
>>>>>> +	/*
>>>>>> +	 * We only start the ISP if we're the only capture device that's
>>>>>> +	 * streaming. Otherwise, it'll already be active.
>>>>>> +	 */
>>>>>> +	if (mali_c55->pipe.start_count == 1) {
>>>>> Do you start streaming on the sensor when the first video node does?
>>>>>
>>>>> This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
>>>>> streaming on the sensor once all video nodes of the pipeline have been
>>>>> started.
>>>> How would you ever know which nodes will be started ?
>>> That can be done with link setup. Any video device that has an active
>>> link to the ISP would need to be started.
>>
>> So if you don't want to stream data from one of the two capture nodes, you'd
>> need to disable the link between it and the resizer? That seems quite
>> clunky. Does it matter if one of them starts a frame or two later? As
>> opposed to both of them starting in sync a frame or two later?
> Video frames on a given queue are lost due to the driver implementation.
> I might consider that to be a driver bug.


This seems a bit odd to me; I think that the implication is when you **queue** a buffer to the 
driver you're targeting a specific frame from the sensor...is that right? What about if you want to 
start streaming on the second capture node at some later point, after the first had already been 
started? I think we'd be in the same situation there, with the already started capture node getting 
buffers filled after the second had had buffers queued, but before you could start it.


>
> It's also true that some use cases could also benefit from the behaviour
> but on regular CSI-2 receivers that's probably quite rare. We'd need
> additional APIs to be able to convey the desired behaviour to the drivers.
>

Dan Scally May 24, 2024, 9:04 a.m. UTC | #11

Hi Sakari

On 23/05/2024 18:53, Sakari Ailus wrote:
> Hi Dan,
>
> On Thu, May 23, 2024 at 02:44:06PM +0100, Dan Scally wrote:
>> Hi Sakari - thanks for the review. Snipping some bits for which I have no comment...
>>
>> On 23/05/2024 09:03, Sakari Ailus wrote:
>>
>> <snip>
>>>> +
>>>> +static unsigned int mali_c55_calculate_bank_num(struct mali_c55 *mali_c55,
>>>> +						unsigned int crop,
>>>> +						unsigned int scale)
>>>> +{
>>>> +	unsigned int tmp;
>>>> +	unsigned int i;
>>>> +
>>>> +	tmp = (scale * 1000) / crop;
>>> This looks like something that can overflow. Can it?
>>
>> Shouldn't be able to; maximum scale width is 8192.
> Ok.
>
> 1000U in that case?


Done

>
>>>> +	for (i = 0; i < MALI_C55_RESIZER_COEFS_NUM_BANKS; i++) {
>>>> +		for (j = 0; j < MALI_C55_RESIZER_COEFS_NUM_ENTRIES; j++) {
>>>> +			mali_c55_write(mali_c55, haddr,
>>>> +				mali_c55_scaler_h_filter_coefficients[i][j]);
>>>> +			mali_c55_write(mali_c55, vaddr,
>>>> +				mali_c55_scaler_v_filter_coefficients[i][j]);
>>>> +
>>>> +			haddr += 4;
>>>> +			vaddr += 4;
>>> sizeof(u32) ?
>>>
>>> Up to you.
>>
>> I think I'll keep it if it's all the same to you
> Well, not the same but I'll let you decide. :-)


OK you're right, the sizeof() is better

>
> ...
>
>>>> +static int mali_c55_tpg_init_state(struct v4l2_subdev *sd,
>>>> +				   struct v4l2_subdev_state *sd_state)
>>>> +{
>>>> +	struct v4l2_mbus_framefmt *fmt;
>>>> +
>>>> +	fmt = v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);
>>> Can be assigned in the declaration.
>>
>> How would you make it fit that way?
> 	struct v4l2_mbus_framefmt *fmt =
> 		v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);


Done - thank you!

>

Dan Scally May 24, 2024, 10:31 a.m. UTC | #12

Hi Sakari

On 23/05/2024 21:57, Sakari Ailus wrote:
> Hi Dan,
>
> On Thu, May 23, 2024 at 03:27:36PM +0100, Dan Scally wrote:
>> Hi Sakari - sorry, one part I missed...
>>
>> On 23/05/2024 09:03, Sakari Ailus wrote:
>>>> +
>>>> +int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable)
>>> Have you considered {enable,disable}_streams? All new drivers should use
>>> these instead of s_stream() now.
>>
>> Although named s_stream this is actually a purely internal function - it's
>> not exposed as part of the subdev video ops. The resizer subdevices
>> similarly don't expose an .s_stream() operation, they're simply started in
>> the callpath of mali_c55_vb2_start_streaming(). I'll split the stop
>> functionality into mali_c55_isp_stop_stream() and rename this
>> mali_c55_isp_start_stream() to make that less confusing.
> Ack. But this might require some rework, depending on based on what
> streaming is actually started. I'm referring to the discussion elsewhere
> in the same thread.
>
>>
>> The TPG subdevice on the other hand does expose an .s_stream() operation,
>> since the intention was to model it exactly like a connected external
>> subdevice. I can switch to the .enable_streams() operation there.
> Sounds good.


Actually, not sure about this...the TPG just has a single source pad, so there's no _routing_ to set 
and as far as I can tell that means there's also no _streams_ to set since they depend on the 
routing - v4l2_subdev_enable_streams() checks the state's stream_configs to make sure the stream 
you're asking to enable exists, and those stream_configs get created when routing is created - so I  
think for now that the TPG has to stay as .s_stream().


In the isp subdevice I can switch to v4l2_subdev_[enable|disable]_streams() and let it fallback to 
.s_stream() for the tpg - that part's fine.


Dan

>>>> +{
>>>> +	struct mali_c55 *mali_c55 = isp->mali_c55;
>>>> +	struct media_pad *source_pad;
>>>> +	struct media_pad *sink_pad;
>>>> +	int ret;
>>>> +
>>>> +	if (!enable) {
>>>> +		if (isp->source)
>>>> +			v4l2_subdev_call(isp->source, video, s_stream, false);
> This call could be v4l2_subdev_disable_streams().
>
>>>> +		isp->source = NULL;
>>>> +
>>>> +		mali_c55_isp_stop(mali_c55);
>>>> +
>>>> +		return 0;
>>>> +	}
>>>> +
>>>> +	sink_pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
>>>> +	source_pad = media_pad_remote_pad_unique(sink_pad);
>>>> +	if (IS_ERR(source_pad)) {
>>>> +		dev_err(mali_c55->dev, "Failed to get source for ISP\n");
>>>> +		return PTR_ERR(source_pad);
>>>> +	}
>>>> +
>>>> +	isp->source = media_entity_to_v4l2_subdev(source_pad->entity);
>>>> +
>>>> +	isp->frame_sequence = 0;
>>>> +	ret = mali_c55_isp_start(mali_c55);
>>>> +	if (ret) {
>>>> +		dev_err(mali_c55->dev, "Failed to start ISP\n");
>>>> +		isp->source = NULL;
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	ret = v4l2_subdev_call(isp->source, video, s_stream, true);
> And this could be v4l2_subdev_enable_streams() as well.
>
>>>> +	if (ret) {
>>>> +		dev_err(mali_c55->dev, "Failed to start ISP source\n");
>>>> +		mali_c55_isp_stop(mali_c55);
>>>> +		return ret;
>>>> +	}
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +

Sakari Ailus May 26, 2024, 3:42 p.m. UTC | #13

Hi Dan,

On Fri, May 24, 2024 at 09:37:04AM +0100, Dan Scally wrote:
> Good morning Sakari
> 
> On 23/05/2024 22:01, Sakari Ailus wrote:
> > Hi Dan,
> > 
> > On Thu, May 23, 2024 at 12:22:45PM +0100, Dan Scally wrote:
> > > Hello
> > > 
> > > On 23/05/2024 10:49, Laurent Pinchart wrote:
> > > > On Thu, May 23, 2024 at 11:48:02AM +0200, Jacopo Mondi wrote:
> > > > > On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
> > > > > > Hi Daniel,
> > > > > [snip]
> > > > > 
> > > > > > > +
> > > > > > > +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
> > > > > > > +{
> > > > > > > +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> > > > > > > +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> > > > > > > +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> > > > > > > +	struct mali_c55_isp *isp = &mali_c55->isp;
> > > > > > > +	int ret;
> > > > > > > +
> > > > > > > +	guard(mutex)(&isp->lock);
> > > > > > > +
> > > > > > > +	ret = pm_runtime_resume_and_get(mali_c55->dev);
> > > > > > > +	if (ret)
> > > > > > > +		return ret;
> > > > > > > +
> > > > > > > +	ret = video_device_pipeline_start(&cap_dev->vdev,
> > > > > > > +					  &cap_dev->mali_c55->pipe);
> > > > > > > +	if (ret) {
> > > > > > > +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
> > > > > > > +			mali_c55_cap_dev_to_name(cap_dev));
> > > > > > > +		goto err_pm_put;
> > > > > > > +	}
> > > > > > > +
> > > > > > > +	mali_c55_cap_dev_stream_enable(cap_dev);
> > > > > > > +	mali_c55_rzr_start_stream(rzr);
> > > > > > > +
> > > > > > > +	/*
> > > > > > > +	 * We only start the ISP if we're the only capture device that's
> > > > > > > +	 * streaming. Otherwise, it'll already be active.
> > > > > > > +	 */
> > > > > > > +	if (mali_c55->pipe.start_count == 1) {
> > > > > > Do you start streaming on the sensor when the first video node does?
> > > > > > 
> > > > > > This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
> > > > > > streaming on the sensor once all video nodes of the pipeline have been
> > > > > > started.
> > > > > How would you ever know which nodes will be started ?
> > > > That can be done with link setup. Any video device that has an active
> > > > link to the ISP would need to be started.
> > > 
> > > So if you don't want to stream data from one of the two capture nodes, you'd
> > > need to disable the link between it and the resizer? That seems quite
> > > clunky. Does it matter if one of them starts a frame or two later? As
> > > opposed to both of them starting in sync a frame or two later?
> > Video frames on a given queue are lost due to the driver implementation.
> > I might consider that to be a driver bug.
> 
> 
> This seems a bit odd to me; I think that the implication is when you
> **queue** a buffer to the driver you're targeting a specific frame from the
> sensor...is that right? What about if you want to start streaming on the

The behaviour there without the request API is somewhat driver specific.
Most driver's don't use it.

> second capture node at some later point, after the first had already been
> started? I think we'd be in the same situation there, with the already
> started capture node getting buffers filled after the second had had buffers
> queued, but before you could start it.

In that case you'd  start both queues but of course you can queue buffers
just to the first node before you need anything from the second one
(assuming this is supported by the driver).

> 
> 
> > 
> > It's also true that some use cases could also benefit from the behaviour
> > but on regular CSI-2 receivers that's probably quite rare. We'd need
> > additional APIs to be able to convey the desired behaviour to the drivers.
> >

Sakari Ailus May 27, 2024, 7:55 a.m. UTC | #14

Hi Dan,

On Fri, May 24, 2024 at 11:31:28AM +0100, Dan Scally wrote:
> Hi Sakari
> 
> On 23/05/2024 21:57, Sakari Ailus wrote:
> > Hi Dan,
> > 
> > On Thu, May 23, 2024 at 03:27:36PM +0100, Dan Scally wrote:
> > > Hi Sakari - sorry, one part I missed...
> > > 
> > > On 23/05/2024 09:03, Sakari Ailus wrote:
> > > > > +
> > > > > +int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable)
> > > > Have you considered {enable,disable}_streams? All new drivers should use
> > > > these instead of s_stream() now.
> > > 
> > > Although named s_stream this is actually a purely internal function - it's
> > > not exposed as part of the subdev video ops. The resizer subdevices
> > > similarly don't expose an .s_stream() operation, they're simply started in
> > > the callpath of mali_c55_vb2_start_streaming(). I'll split the stop
> > > functionality into mali_c55_isp_stop_stream() and rename this
> > > mali_c55_isp_start_stream() to make that less confusing.
> > Ack. But this might require some rework, depending on based on what
> > streaming is actually started. I'm referring to the discussion elsewhere
> > in the same thread.
> > 
> > > 
> > > The TPG subdevice on the other hand does expose an .s_stream() operation,
> > > since the intention was to model it exactly like a connected external
> > > subdevice. I can switch to the .enable_streams() operation there.
> > Sounds good.
> 
> 
> Actually, not sure about this...the TPG just has a single source pad, so
> there's no _routing_ to set and as far as I can tell that means there's also
> no _streams_ to set since they depend on the routing -
> v4l2_subdev_enable_streams() checks the state's stream_configs to make sure
> the stream you're asking to enable exists, and those stream_configs get
> created when routing is created - so I  think for now that the TPG has to
> stay as .s_stream().

With Tomi's patches
<URL:https://lore.kernel.org/linux-media/[e-mail]/>
you no longer need routes to use {enable,disable}_streams.

> 
> 
> In the isp subdevice I can switch to v4l2_subdev_[enable|disable]_streams()
> and let it fallback to .s_stream() for the tpg - that part's fine.

Laurent Pinchart May 29, 2024, 8:28 p.m. UTC | #15

On Sun, May 26, 2024 at 03:42:54PM +0000, Sakari Ailus wrote:
> On Fri, May 24, 2024 at 09:37:04AM +0100, Dan Scally wrote:
> > On 23/05/2024 22:01, Sakari Ailus wrote:
> > > On Thu, May 23, 2024 at 12:22:45PM +0100, Dan Scally wrote:
> > > > On 23/05/2024 10:49, Laurent Pinchart wrote:
> > > > > On Thu, May 23, 2024 at 11:48:02AM +0200, Jacopo Mondi wrote:
> > > > > > On Thu, May 23, 2024 at 08:03:49AM GMT, Sakari Ailus wrote:
> > > > > > > Hi Daniel,
> > > > > > [snip]
> > > > > > 
> > > > > > > > +
> > > > > > > > +static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
> > > > > > > > +{
> > > > > > > > +	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
> > > > > > > > +	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
> > > > > > > > +	struct mali_c55_resizer *rzr = cap_dev->rzr;
> > > > > > > > +	struct mali_c55_isp *isp = &mali_c55->isp;
> > > > > > > > +	int ret;
> > > > > > > > +
> > > > > > > > +	guard(mutex)(&isp->lock);
> > > > > > > > +
> > > > > > > > +	ret = pm_runtime_resume_and_get(mali_c55->dev);
> > > > > > > > +	if (ret)
> > > > > > > > +		return ret;
> > > > > > > > +
> > > > > > > > +	ret = video_device_pipeline_start(&cap_dev->vdev,
> > > > > > > > +					  &cap_dev->mali_c55->pipe);
> > > > > > > > +	if (ret) {
> > > > > > > > +		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
> > > > > > > > +			mali_c55_cap_dev_to_name(cap_dev));
> > > > > > > > +		goto err_pm_put;
> > > > > > > > +	}
> > > > > > > > +
> > > > > > > > +	mali_c55_cap_dev_stream_enable(cap_dev);
> > > > > > > > +	mali_c55_rzr_start_stream(rzr);
> > > > > > > > +
> > > > > > > > +	/*
> > > > > > > > +	 * We only start the ISP if we're the only capture device that's
> > > > > > > > +	 * streaming. Otherwise, it'll already be active.
> > > > > > > > +	 */
> > > > > > > > +	if (mali_c55->pipe.start_count == 1) {
> > > > > > >
> > > > > > > Do you start streaming on the sensor when the first video node does?
> > > > > > > 
> > > > > > > This means that frames may be lost. E.g. the IPU6 ISYS driver only starts
> > > > > > > streaming on the sensor once all video nodes of the pipeline have been
> > > > > > > started.
> > > > > >
> > > > > > How would you ever know which nodes will be started ?
> > > > >
> > > > > That can be done with link setup. Any video device that has an active
> > > > > link to the ISP would need to be started.
> > > > 
> > > > So if you don't want to stream data from one of the two capture nodes, you'd
> > > > need to disable the link between it and the resizer? That seems quite
> > > > clunky.

Why so ? I think it's a neat solution to communicate userspace's
expected behaviour to the driver.

> > > > Does it matter if one of them starts a frame or two later? As
> > > > opposed to both of them starting in sync a frame or two later?
> > >
> > > Video frames on a given queue are lost due to the driver implementation.
> > > I might consider that to be a driver bug.
> > 
> > This seems a bit odd to me; I think that the implication is when you
> > **queue** a buffer to the driver you're targeting a specific frame from the
> > sensor...is that right? What about if you want to start streaming on the
> 
> The behaviour there without the request API is somewhat driver specific.
> Most driver's don't use it.

I agree. If we want some of the outputs to be optional, we need the
request API. Without it, all video devices that are started (or I'd like
to say included in the pipeline) will need buffers, and I think they
should start at the same time.

> > second capture node at some later point, after the first had already been
> > started? I think we'd be in the same situation there, with the already
> > started capture node getting buffers filled after the second had had buffers
> > queued, but before you could start it.
> 
> In that case you'd  start both queues but of course you can queue buffers
> just to the first node before you need anything from the second one
> (assuming this is supported by the driver).
> 
> > > It's also true that some use cases could also benefit from the behaviour
> > > but on regular CSI-2 receivers that's probably quite rare. We'd need
> > > additional APIs to be able to convey the desired behaviour to the drivers.

Patch

diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index 91e54215de3a..cd92c024e039 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -65,6 +65,7 @@  config VIDEO_MUX
 source "drivers/media/platform/allegro-dvt/Kconfig"
 source "drivers/media/platform/amlogic/Kconfig"
 source "drivers/media/platform/amphion/Kconfig"
+source "drivers/media/platform/arm/Kconfig"
 source "drivers/media/platform/aspeed/Kconfig"
 source "drivers/media/platform/atmel/Kconfig"
 source "drivers/media/platform/cadence/Kconfig"
diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile
index 3296ec1ebe16..ea6624c62559 100644
--- a/drivers/media/platform/Makefile
+++ b/drivers/media/platform/Makefile
@@ -8,6 +8,7 @@ 
 obj-y += allegro-dvt/
 obj-y += amlogic/
 obj-y += amphion/
+obj-y += arm/
 obj-y += aspeed/
 obj-y += atmel/
 obj-y += cadence/
diff --git a/drivers/media/platform/arm/Kconfig b/drivers/media/platform/arm/Kconfig
new file mode 100644
index 000000000000..4f0764c329c7
--- /dev/null
+++ b/drivers/media/platform/arm/Kconfig
@@ -0,0 +1,5 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+
+comment "ARM media platform drivers"
+
+source "drivers/media/platform/arm/mali-c55/Kconfig"
diff --git a/drivers/media/platform/arm/Makefile b/drivers/media/platform/arm/Makefile
new file mode 100644
index 000000000000..8cc4918725ef
--- /dev/null
+++ b/drivers/media/platform/arm/Makefile
@@ -0,0 +1,2 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+obj-y += mali-c55/
diff --git a/drivers/media/platform/arm/mali-c55/Kconfig b/drivers/media/platform/arm/mali-c55/Kconfig
new file mode 100644
index 000000000000..602085e28b01
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/Kconfig
@@ -0,0 +1,18 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+config VIDEO_MALI_C55
+	tristate "ARM Mali-C55 Image Signal Processor driver"
+	depends on V4L_PLATFORM_DRIVERS
+	depends on VIDEO_DEV && OF
+	depends on ARCH_VEXPRESS || COMPILE_TEST
+	select MEDIA_CONTROLLER
+	select VIDEO_V4L2_SUBDEV_API
+	select VIDEOBUF2_DMA_CONTIG
+	select VIDEOBUF2_VMALLOC
+	select V4L2_FWNODE
+	select GENERIC_PHY_MIPI_DPHY
+	default n
+	help
+	  Enable this to support Arm's Mali-C55 Image Signal Processor.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called mali-c55.
diff --git a/drivers/media/platform/arm/mali-c55/Makefile b/drivers/media/platform/arm/mali-c55/Makefile
new file mode 100644
index 000000000000..77dcb2fbf0f4
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/Makefile
@@ -0,0 +1,9 @@ 
+# SPDX-License-Identifier: GPL-2.0
+
+mali-c55-y := mali-c55-capture.o \
+	      mali-c55-core.o \
+	      mali-c55-isp.o \
+	      mali-c55-tpg.o \
+	      mali-c55-resizer.o
+
+obj-$(CONFIG_VIDEO_MALI_C55) += mali-c55.o
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-capture.c b/drivers/media/platform/arm/mali-c55/mali-c55-capture.c
new file mode 100644
index 000000000000..4fcd52437b36
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-capture.c
@@ -0,0 +1,955 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Mali-C55 ISP Driver - Video capture devices
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#include <linux/cleanup.h>
+#include <linux/minmax.h>
+#include <linux/pm_runtime.h>
+#include <linux/string.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-dev.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-subdev.h>
+#include <media/videobuf2-core.h>
+#include <media/videobuf2-dma-contig.h>
+
+#include "mali-c55-common.h"
+#include "mali-c55-registers.h"
+
+/*
+ * The Mali-C55 ISP has up to two output pipes; known as full resolution and
+ * down scaled. The register space for these is laid out identically, but offset
+ * by 372 bytes.
+ */
+#define MALI_C55_CAP_DEV_FR_REG_OFFSET		0x0
+#define MALI_C55_CAP_DEV_DS_REG_OFFSET		0x174
+
+static const struct mali_c55_fmt mali_c55_fmts[] = {
+	/*
+	 * This table is missing some entries which need further work or
+	 * investigation:
+	 *
+	 * Base mode 1 is a backwards V4L2_PIX_FMT_XRGB32 with no V4L2 equivalent
+	 * Base mode 5 is "Generic Data"
+	 * Base mode 8 is a backwards V4L2_PIX_FMT_XYUV32 - no V4L2 equivalent
+	 * Base mode 9 seems to have no V4L2 equivalent
+	 * Base mode 17, 19 and 20 describe formats which seem to have no V4L2
+	 * equivalent
+	 */
+	{
+		.fourcc = V4L2_PIX_FMT_ARGB2101010,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_RGB121212_1X36,
+			MEDIA_BUS_FMT_RGB202020_1X60,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_A2R10G10B10,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_RGB565,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_RGB121212_1X36,
+			MEDIA_BUS_FMT_RGB202020_1X60,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_RGB565,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_BGR24,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_RGB121212_1X36,
+			MEDIA_BUS_FMT_RGB202020_1X60,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_RGB24,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_YUYV,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_YUV10_1X30,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_YUY2,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_UYVY,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_YUV10_1X30,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_UYVY,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_Y210,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_YUV10_1X30,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_Y210,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	/*
+	 * This is something of a hack, the ISP thinks it's running NV12M but
+	 * by setting uv_plane = 0 we simply discard that planes and only output
+	 * the Y-plane.
+	 */
+	{
+		.fourcc = V4L2_PIX_FMT_GREY,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_YUV10_1X30,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_NV12_21,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_NV12M,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_YUV10_1X30,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_NV12_21,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT1
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_NV21M,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_YUV10_1X30,
+		},
+		.is_raw = false,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_NV12_21,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT2
+		}
+	},
+	/*
+	 * RAW uncompressed formats are all packed in 16 bpp.
+	 * TODO: Expand this list to encompass all possible RAW formats.
+	 */
+	{
+		.fourcc = V4L2_PIX_FMT_SRGGB12,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_SRGGB12_1X12,
+		},
+		.is_raw = true,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_RAW16,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_SBGGR12,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_SBGGR12_1X12,
+		},
+		.is_raw = true,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_RAW16,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_SGBRG12,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_SGBRG12_1X12,
+		},
+		.is_raw = true,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_RAW16,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+	{
+		.fourcc = V4L2_PIX_FMT_SGRBG12,
+		.mbus_codes = {
+			MEDIA_BUS_FMT_SGRBG12_1X12,
+		},
+		.is_raw = true,
+		.registers = {
+			.base_mode = MALI_C55_OUTPUT_RAW16,
+			.uv_plane = MALI_C55_OUTPUT_PLANE_ALT0
+		}
+	},
+};
+
+static bool mali_c55_mbus_code_can_produce_fmt(const struct mali_c55_fmt *fmt,
+					       u32 code)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(fmt->mbus_codes); i++) {
+		if (fmt->mbus_codes[i] == code)
+			return true;
+	}
+
+	return false;
+}
+
+bool mali_c55_format_is_raw(unsigned int mbus_code)
+{
+	for (unsigned int i = 0; i < ARRAY_SIZE(mali_c55_fmts); i++) {
+		if (mali_c55_fmts[i].mbus_codes[0] == mbus_code)
+			return mali_c55_fmts[i].is_raw;
+	}
+
+	return false;
+}
+
+static const struct mali_c55_fmt *mali_c55_format_from_pix(const u32 pixelformat)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55_fmts); i++) {
+		if (mali_c55_fmts[i].fourcc == pixelformat)
+			return &mali_c55_fmts[i];
+	}
+
+	/*
+	 * If we find no matching pixelformat, we'll just default to the first
+	 * one for now.
+	 */
+
+	return &mali_c55_fmts[0];
+}
+
+static const char * const capture_device_names[] = {
+	"mali-c55 fr",
+	"mali-c55 ds",
+	"mali-c55 3a stats",
+	"mali-c55 params",
+};
+
+static const char *mali_c55_cap_dev_to_name(struct mali_c55_cap_dev *cap)
+{
+	if (cap->reg_offset == MALI_C55_CAP_DEV_FR_REG_OFFSET)
+		return capture_device_names[0];
+	else if (cap->reg_offset == MALI_C55_CAP_DEV_DS_REG_OFFSET)
+		return capture_device_names[1];
+
+	return "params/stat not supported yet";
+}
+
+static int mali_c55_link_validate(struct media_link *link)
+{
+	struct video_device *vdev =
+		media_entity_to_video_device(link->sink->entity);
+	struct mali_c55_cap_dev *cap_dev = video_get_drvdata(vdev);
+	struct v4l2_subdev *sd =
+		media_entity_to_v4l2_subdev(link->source->entity);
+	const struct v4l2_pix_format_mplane *pix_mp;
+	const struct mali_c55_fmt *cap_fmt;
+	struct v4l2_subdev_format sd_fmt = {
+		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
+		.pad = link->source->index,
+	};
+	int ret;
+
+	ret = v4l2_subdev_call(sd, pad, get_fmt, NULL, &sd_fmt);
+	if (ret)
+		return ret;
+
+	pix_mp = &cap_dev->mode.pix_mp;
+	cap_fmt = cap_dev->mode.capture_fmt;
+
+	if (sd_fmt.format.width != pix_mp->width ||
+	    sd_fmt.format.height != pix_mp->height) {
+		dev_dbg(cap_dev->mali_c55->dev,
+			"link '%s':%u -> '%s':%u not valid: %ux%u != %ux%u\n",
+			link->source->entity->name, link->source->index,
+			link->sink->entity->name, link->sink->index,
+			sd_fmt.format.width, sd_fmt.format.height,
+			pix_mp->width, pix_mp->height);
+		return -EPIPE;
+	}
+
+	if (!mali_c55_mbus_code_can_produce_fmt(cap_fmt, sd_fmt.format.code)) {
+		dev_dbg(cap_dev->mali_c55->dev,
+			"link '%s':%u -> '%s':%u not valid: mbus_code 0x%04x cannot produce pixel format %p4cc\n",
+			link->source->entity->name, link->source->index,
+			link->sink->entity->name, link->sink->index,
+			sd_fmt.format.code, &pix_mp->pixelformat);
+		return -EPIPE;
+	}
+
+	return 0;
+}
+
+static const struct media_entity_operations mali_c55_media_ops = {
+	.link_validate = mali_c55_link_validate,
+};
+
+static int mali_c55_vb2_queue_setup(struct vb2_queue *q, unsigned int *num_buffers,
+				    unsigned int *num_planes, unsigned int sizes[],
+				    struct device *alloc_devs[])
+{
+	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
+	unsigned int i;
+
+	if (*num_planes) {
+		if (*num_planes != cap_dev->mode.pix_mp.num_planes)
+			return -EINVAL;
+
+		for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++)
+			if (sizes[i] < cap_dev->mode.pix_mp.plane_fmt[i].sizeimage)
+				return -EINVAL;
+	} else {
+		*num_planes = cap_dev->mode.pix_mp.num_planes;
+		for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++)
+			sizes[i] = cap_dev->mode.pix_mp.plane_fmt[i].sizeimage;
+	}
+
+	return 0;
+}
+
+static void mali_c55_buf_queue(struct vb2_buffer *vb)
+{
+	struct mali_c55_cap_dev *cap_dev = vb2_get_drv_priv(vb->vb2_queue);
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct mali_c55_buffer *buf = container_of(vbuf,
+						   struct mali_c55_buffer, vb);
+	unsigned int i;
+
+	buf->plane_done[MALI_C55_PLANE_Y] = false;
+
+	/*
+	 * If we're in a single-plane format we flag the other plane as done
+	 * already so it's dequeued appropriately later
+	 */
+	buf->plane_done[MALI_C55_PLANE_UV] = cap_dev->mode.pix_mp.num_planes <= 1;
+
+	for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++) {
+		unsigned long size = cap_dev->mode.pix_mp.plane_fmt[i].sizeimage;
+
+		vb2_set_plane_payload(vb, i, size);
+	}
+
+	spin_lock(&cap_dev->buffers.lock);
+	list_add_tail(&buf->queue, &cap_dev->buffers.queue);
+	spin_unlock(&cap_dev->buffers.lock);
+}
+
+static int mali_c55_buf_init(struct vb2_buffer *vb)
+{
+	struct mali_c55_cap_dev *cap_dev = vb2_get_drv_priv(vb->vb2_queue);
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct mali_c55_buffer *buf = container_of(vbuf,
+						   struct mali_c55_buffer, vb);
+	unsigned int i;
+
+	for (i = 0; i < cap_dev->mode.pix_mp.num_planes; i++)
+		buf->addrs[i] = vb2_dma_contig_plane_dma_addr(vb, i);
+
+	return 0;
+}
+
+void mali_c55_set_next_buffer(struct mali_c55_cap_dev *cap_dev)
+{
+	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
+
+	guard(spinlock)(&cap_dev->buffers.lock);
+
+	cap_dev->buffers.curr = cap_dev->buffers.next;
+	cap_dev->buffers.next = NULL;
+
+	if (!list_empty(&cap_dev->buffers.queue)) {
+		struct v4l2_pix_format_mplane *pix_mp;
+		const struct v4l2_format_info *info;
+		u32 *addrs;
+
+		pix_mp = &cap_dev->mode.pix_mp;
+		info = v4l2_format_info(pix_mp->pixelformat);
+
+		mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
+				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x01);
+		if (cap_dev->mode.capture_fmt->registers.uv_plane)
+			mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
+				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x01);
+
+		cap_dev->buffers.next = list_first_entry(&cap_dev->buffers.queue,
+							 struct mali_c55_buffer,
+							 queue);
+		list_del(&cap_dev->buffers.next->queue);
+
+		addrs = cap_dev->buffers.next->addrs;
+		mali_c55_write(mali_c55,
+			MALI_C55_REG_Y_WRITER_BANKS_BASE(cap_dev->reg_offset),
+			addrs[MALI_C55_PLANE_Y]);
+		mali_c55_write(mali_c55,
+			MALI_C55_REG_UV_WRITER_BANKS_BASE(cap_dev->reg_offset),
+			addrs[MALI_C55_PLANE_UV]);
+		mali_c55_write(mali_c55,
+			MALI_C55_REG_Y_WRITER_OFFSET(cap_dev->reg_offset),
+			pix_mp->width * info->bpp[MALI_C55_PLANE_Y]);
+		mali_c55_write(mali_c55,
+			MALI_C55_REG_UV_WRITER_OFFSET(cap_dev->reg_offset),
+			pix_mp->width * info->bpp[MALI_C55_PLANE_UV]
+			/ info->hdiv);
+	} else {
+		/*
+		 * If we underflow then we can tell the ISP that we don't want
+		 * to write out the next frame.
+		 */
+		mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
+				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
+		mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
+				MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
+	}
+}
+
+static void mali_c55_handle_buffer(struct mali_c55_buffer *curr_buf,
+				   unsigned int framecount)
+{
+	curr_buf->vb.vb2_buf.timestamp = ktime_get_boottime_ns();
+	curr_buf->vb.field = V4L2_FIELD_NONE;
+	curr_buf->vb.sequence = framecount;
+	vb2_buffer_done(&curr_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
+}
+
+/**
+ * mali_c55_set_plane_done - mark the plane as written and process the buffer if
+ *			     both planes are finished.
+ * @cap_dev:  pointer to the fr or ds pipe output
+ * @plane:    the plane to mark as completed
+ *
+ * The Mali C55 ISP has muliplanar outputs for some formats that come with two
+ * separate "buffer write completed" interrupts - we need to flag each plane's
+ * completion and check whether both planes are done - if so, complete the buf
+ * in vb2.
+ */
+void mali_c55_set_plane_done(struct mali_c55_cap_dev *cap_dev,
+			     enum mali_c55_planes plane)
+{
+	struct mali_c55_isp *isp = &cap_dev->mali_c55->isp;
+	struct mali_c55_buffer *curr_buf;
+
+	guard(spinlock)(&cap_dev->buffers.lock);
+	curr_buf = cap_dev->buffers.curr;
+
+	/*
+	 * This _should_ never happen. If no buffer was available from vb2 then
+	 * we tell the ISP not to bother writing the next frame, which means the
+	 * interrupts that call this function should never trigger. If it does
+	 * happen then one of our assumptions is horribly wrong - complain
+	 * loudly and do nothing.
+	 */
+	if (!curr_buf) {
+		dev_err(cap_dev->mali_c55->dev, "%s null buffer in %s()\n",
+			mali_c55_cap_dev_to_name(cap_dev), __func__);
+		return;
+	}
+
+	/* If the other plane is also done... */
+	if (curr_buf->plane_done[~plane & 1]) {
+		mali_c55_handle_buffer(curr_buf, isp->frame_sequence);
+		cap_dev->buffers.curr = NULL;
+	} else {
+		curr_buf->plane_done[plane] = true;
+	}
+}
+
+static void mali_c55_cap_dev_stream_disable(struct mali_c55_cap_dev *cap_dev)
+{
+	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
+
+	mali_c55_update_bits(mali_c55,
+			     MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
+			     MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
+	mali_c55_update_bits(mali_c55,
+			     MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
+			     MALI_C55_WRITER_FRAME_WRITE_MASK, 0x00);
+}
+
+static void mali_c55_cap_dev_stream_enable(struct mali_c55_cap_dev *cap_dev)
+{
+	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
+
+	/*
+	 * The Mali ISP can hold up to 5 buffer addresses and simply cycle
+	 * through them, but it's not clear to me that the vb2 queue _guarantees_
+	 * it will queue buffers to the driver in a fixed order, and ensuring
+	 * we call vb2_buffer_done() for the right buffer seems to me to add
+	 * pointless complexity given in multi-context mode we'd need to
+	 * re-write those registers every frame anyway...so we tell the ISP to
+	 * use a single register and update it for each frame.
+	 */
+	mali_c55_update_bits(mali_c55,
+			MALI_C55_REG_Y_WRITER_BANKS_CONFIG(cap_dev->reg_offset),
+			MALI_C55_REG_Y_WRITER_MAX_BANKS_MASK, 0);
+	mali_c55_update_bits(mali_c55,
+			MALI_C55_REG_UV_WRITER_BANKS_CONFIG(cap_dev->reg_offset),
+			MALI_C55_REG_UV_WRITER_MAX_BANKS_MASK, 0);
+
+	/*
+	 * We only queue a buffer in the streamon path if this is the first of
+	 * the capture devices to start streaming. If the ISP is already running
+	 * then we rely on the ISP_START interrupt to queue the first buffer for
+	 * this capture device.
+	 */
+	if (mali_c55->pipe.start_count == 1)
+		mali_c55_set_next_buffer(cap_dev);
+}
+
+static void mali_c55_cap_dev_return_buffers(struct mali_c55_cap_dev *cap_dev,
+					    enum vb2_buffer_state state)
+{
+	struct mali_c55_buffer *buf, *tmp;
+
+	guard(spinlock)(&cap_dev->buffers.lock);
+
+	if (cap_dev->buffers.curr) {
+		vb2_buffer_done(&cap_dev->buffers.curr->vb.vb2_buf,
+				state);
+		cap_dev->buffers.curr = NULL;
+	}
+
+	if (cap_dev->buffers.next) {
+		vb2_buffer_done(&cap_dev->buffers.next->vb.vb2_buf,
+				state);
+		cap_dev->buffers.next = NULL;
+	}
+
+	list_for_each_entry_safe(buf, tmp, &cap_dev->buffers.queue, queue) {
+		list_del(&buf->queue);
+		vb2_buffer_done(&buf->vb.vb2_buf, state);
+	}
+}
+
+static int mali_c55_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
+{
+	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
+	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
+	struct mali_c55_resizer *rzr = cap_dev->rzr;
+	struct mali_c55_isp *isp = &mali_c55->isp;
+	int ret;
+
+	guard(mutex)(&isp->lock);
+
+	ret = pm_runtime_resume_and_get(mali_c55->dev);
+	if (ret)
+		return ret;
+
+	ret = video_device_pipeline_start(&cap_dev->vdev,
+					  &cap_dev->mali_c55->pipe);
+	if (ret) {
+		dev_err(mali_c55->dev, "%s failed to start media pipeline\n",
+			mali_c55_cap_dev_to_name(cap_dev));
+		goto err_pm_put;
+	}
+
+	mali_c55_cap_dev_stream_enable(cap_dev);
+	mali_c55_rzr_start_stream(rzr);
+
+	/*
+	 * We only start the ISP if we're the only capture device that's
+	 * streaming. Otherwise, it'll already be active.
+	 */
+	if (mali_c55->pipe.start_count == 1) {
+		ret = mali_c55_isp_s_stream(isp, true);
+		if (ret)
+			goto err_disable_cap_dev;
+	}
+
+	return 0;
+
+err_disable_cap_dev:
+	mali_c55_cap_dev_stream_disable(cap_dev);
+	video_device_pipeline_stop(&cap_dev->vdev);
+err_pm_put:
+	pm_runtime_put(mali_c55->dev);
+	mali_c55_cap_dev_return_buffers(cap_dev, VB2_BUF_STATE_QUEUED);
+
+	return ret;
+}
+
+static void mali_c55_vb2_stop_streaming(struct vb2_queue *q)
+{
+	struct mali_c55_cap_dev *cap_dev = q->drv_priv;
+	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
+	struct mali_c55_resizer *rzr = cap_dev->rzr;
+	struct mali_c55_isp *isp = &mali_c55->isp;
+
+	guard(mutex)(&isp->lock);
+
+	/*
+	 * If one of the other capture nodes is streaming, we shouldn't
+	 * disable the ISP here.
+	 */
+	if (mali_c55->pipe.start_count == 1)
+		mali_c55_isp_s_stream(&mali_c55->isp, false);
+
+	mali_c55_rzr_stop_stream(rzr);
+	mali_c55_cap_dev_stream_disable(cap_dev);
+	mali_c55_cap_dev_return_buffers(cap_dev, VB2_BUF_STATE_ERROR);
+	video_device_pipeline_stop(&cap_dev->vdev);
+	pm_runtime_put(mali_c55->dev);
+}
+
+static const struct vb2_ops mali_c55_vb2_ops = {
+	.queue_setup		= &mali_c55_vb2_queue_setup,
+	.buf_queue		= &mali_c55_buf_queue,
+	.buf_init		= &mali_c55_buf_init,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+	.start_streaming	= &mali_c55_vb2_start_streaming,
+	.stop_streaming		= &mali_c55_vb2_stop_streaming,
+};
+
+static const struct v4l2_file_operations mali_c55_v4l2_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = video_ioctl2,
+	.open = v4l2_fh_open,
+	.release = vb2_fop_release,
+	.poll = vb2_fop_poll,
+	.mmap = vb2_fop_mmap,
+};
+
+static void mali_c55_try_fmt(struct v4l2_pix_format_mplane *pix_mp)
+{
+	const struct mali_c55_fmt *capture_format;
+	const struct v4l2_format_info *info;
+	struct v4l2_plane_pix_format *plane;
+	unsigned int i;
+
+	capture_format = mali_c55_format_from_pix(pix_mp->pixelformat);
+	pix_mp->pixelformat = capture_format->fourcc;
+
+	pix_mp->width = clamp(pix_mp->width, MALI_C55_MIN_WIDTH,
+			      MALI_C55_MAX_WIDTH);
+	pix_mp->height = clamp(pix_mp->height, MALI_C55_MIN_HEIGHT,
+			       MALI_C55_MAX_HEIGHT);
+
+	pix_mp->field = V4L2_FIELD_NONE;
+	pix_mp->colorspace = V4L2_COLORSPACE_DEFAULT;
+	pix_mp->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
+	pix_mp->quantization = V4L2_QUANTIZATION_DEFAULT;
+
+	info = v4l2_format_info(pix_mp->pixelformat);
+	pix_mp->num_planes = info->mem_planes;
+	memset(pix_mp->plane_fmt, 0, sizeof(pix_mp->plane_fmt));
+
+	pix_mp->plane_fmt[0].bytesperline = info->bpp[0] * pix_mp->width;
+	pix_mp->plane_fmt[0].sizeimage = info->bpp[0] * pix_mp->width
+				       * pix_mp->height;
+
+	for (i = 1; i < info->comp_planes; i++) {
+		plane = &pix_mp->plane_fmt[i];
+
+		plane->bytesperline = DIV_ROUND_UP(info->bpp[i] * pix_mp->width,
+						   info->hdiv);
+		plane->sizeimage = DIV_ROUND_UP(
+					plane->bytesperline * pix_mp->height,
+					info->vdiv);
+	}
+
+	if (info->mem_planes == 1) {
+		for (i = 1; i < info->comp_planes; i++) {
+			plane = &pix_mp->plane_fmt[i];
+			pix_mp->plane_fmt[0].sizeimage += plane->sizeimage;
+		}
+	}
+}
+
+static int mali_c55_try_fmt_vid_cap_mplane(struct file *file, void *fh,
+					   struct v4l2_format *f)
+{
+	mali_c55_try_fmt(&f->fmt.pix_mp);
+
+	return 0;
+}
+
+static void mali_c55_set_format(struct mali_c55_cap_dev *cap_dev,
+				struct v4l2_pix_format_mplane *pix_mp)
+{
+	const struct mali_c55_fmt *capture_format;
+	struct mali_c55 *mali_c55 = cap_dev->mali_c55;
+	const struct v4l2_format_info *info;
+
+	mali_c55_try_fmt(pix_mp);
+	capture_format = mali_c55_format_from_pix(pix_mp->pixelformat);
+	info = v4l2_format_info(pix_mp->pixelformat);
+	if (WARN_ON(!info))
+		return;
+
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_Y_WRITER_MODE(cap_dev->reg_offset),
+		       capture_format->registers.base_mode);
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_ACTIVE_OUT_Y_SIZE(cap_dev->reg_offset),
+		       MALI_C55_REG_ACTIVE_OUT_SIZE_W(pix_mp->width) |
+		       MALI_C55_REG_ACTIVE_OUT_SIZE_H(pix_mp->height));
+
+	if (info->mem_planes > 1) {
+		mali_c55_write(mali_c55,
+			       MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
+			       capture_format->registers.base_mode);
+		mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_UV_WRITER_MODE(cap_dev->reg_offset),
+				MALI_C55_WRITER_SUBMODE_MASK,
+				capture_format->registers.uv_plane);
+
+		mali_c55_write(mali_c55,
+			MALI_C55_REG_ACTIVE_OUT_UV_SIZE(cap_dev->reg_offset),
+			MALI_C55_REG_ACTIVE_OUT_SIZE_W(pix_mp->width) |
+			MALI_C55_REG_ACTIVE_OUT_SIZE_H(pix_mp->height));
+	}
+
+	if (info->pixel_enc == V4L2_PIXEL_ENC_YUV) {
+		/*
+		 * TODO: Figure out the colour matrix coefficients and calculate
+		 * and write them here.
+		 */
+
+		mali_c55_write(mali_c55,
+			       MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
+			       MALI_C55_CS_CONV_MATRIX_MASK);
+
+		if (info->hdiv > 1)
+			mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
+				MALI_C55_CS_CONV_HORZ_DOWNSAMPLE_MASK, 0x01);
+		if (info->vdiv > 1)
+			mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
+				MALI_C55_CS_CONV_VERT_DOWNSAMPLE_MASK, 0x01);
+		if (info->hdiv > 1 || info->vdiv > 1)
+			mali_c55_update_bits(mali_c55,
+				MALI_C55_REG_CS_CONV_CONFIG(cap_dev->reg_offset),
+				MALI_C55_CS_CONV_FILTER_MASK, 0x01);
+	}
+
+	cap_dev->mode.pix_mp = *pix_mp;
+	cap_dev->mode.capture_fmt = capture_format;
+}
+
+static int mali_c55_s_fmt_vid_cap_mplane(struct file *file, void *fh,
+					 struct v4l2_format *f)
+{
+	struct mali_c55_cap_dev *cap_dev = video_drvdata(file);
+
+	if (vb2_is_busy(&cap_dev->queue))
+		return -EBUSY;
+
+	mali_c55_set_format(cap_dev, &f->fmt.pix_mp);
+
+	return 0;
+}
+
+static int mali_c55_g_fmt_vid_cap_mplane(struct file *file, void *fh,
+					 struct v4l2_format *f)
+{
+	struct mali_c55_cap_dev *cap_dev = video_drvdata(file);
+
+	f->fmt.pix_mp = cap_dev->mode.pix_mp;
+
+	return 0;
+}
+
+static int mali_c55_enum_fmt_vid_cap_mplane(struct file *file, void *fh,
+					    struct v4l2_fmtdesc *f)
+{
+	struct mali_c55_cap_dev *cap_dev = video_drvdata(file);
+	unsigned int j = 0;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55_fmts); i++) {
+		if (f->mbus_code &&
+		    !mali_c55_mbus_code_can_produce_fmt(&mali_c55_fmts[i],
+						       f->mbus_code))
+			continue;
+
+		/* Downscale pipe can't output RAW formats */
+		if (mali_c55_fmts[i].is_raw &&
+		    cap_dev->reg_offset == MALI_C55_CAP_DEV_DS_REG_OFFSET)
+			continue;
+
+		if (j++ == f->index) {
+			f->pixelformat = mali_c55_fmts[i].fourcc;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int mali_c55_querycap(struct file *file, void *fh,
+			     struct v4l2_capability *cap)
+{
+	strscpy(cap->driver, MALI_C55_DRIVER_NAME, sizeof(cap->driver));
+	strscpy(cap->card, "ARM Mali-C55 ISP", sizeof(cap->card));
+
+	return 0;
+}
+
+static const struct v4l2_ioctl_ops mali_c55_v4l2_ioctl_ops = {
+	.vidioc_reqbufs = vb2_ioctl_reqbufs,
+	.vidioc_querybuf = vb2_ioctl_querybuf,
+	.vidioc_create_bufs = vb2_ioctl_create_bufs,
+	.vidioc_qbuf = vb2_ioctl_qbuf,
+	.vidioc_expbuf = vb2_ioctl_expbuf,
+	.vidioc_dqbuf = vb2_ioctl_dqbuf,
+	.vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+	.vidioc_streamon = vb2_ioctl_streamon,
+	.vidioc_streamoff = vb2_ioctl_streamoff,
+	.vidioc_try_fmt_vid_cap_mplane = mali_c55_try_fmt_vid_cap_mplane,
+	.vidioc_s_fmt_vid_cap_mplane = mali_c55_s_fmt_vid_cap_mplane,
+	.vidioc_g_fmt_vid_cap_mplane = mali_c55_g_fmt_vid_cap_mplane,
+	.vidioc_enum_fmt_vid_cap = mali_c55_enum_fmt_vid_cap_mplane,
+	.vidioc_querycap = mali_c55_querycap,
+	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+};
+
+int mali_c55_register_capture_devs(struct mali_c55 *mali_c55)
+{
+	struct v4l2_pix_format_mplane pix_mp;
+	struct mali_c55_cap_dev *cap_dev;
+	struct video_device *vdev;
+	struct vb2_queue *vb2q;
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55->cap_devs); i++) {
+		cap_dev = &mali_c55->cap_devs[i];
+		vdev = &cap_dev->vdev;
+		vb2q = &cap_dev->queue;
+
+		/*
+		 * The downscale output pipe is an optional block within the ISP
+		 * so we need to check whether it's actually been fitted or not.
+		 */
+
+		if (i == MALI_C55_CAP_DEV_DS &&
+		    !(mali_c55->capabilities & MALI_C55_GPS_DS_PIPE_FITTED))
+			continue;
+
+		cap_dev->mali_c55 = mali_c55;
+		mutex_init(&cap_dev->lock);
+		INIT_LIST_HEAD(&cap_dev->buffers.queue);
+
+		switch (i) {
+		case MALI_C55_CAP_DEV_FR:
+			cap_dev->rzr = &mali_c55->resizers[MALI_C55_RZR_FR];
+			cap_dev->reg_offset = MALI_C55_CAP_DEV_FR_REG_OFFSET;
+			break;
+		case MALI_C55_CAP_DEV_DS:
+			cap_dev->rzr = &mali_c55->resizers[MALI_C55_RZR_DS];
+			cap_dev->reg_offset = MALI_C55_CAP_DEV_DS_REG_OFFSET;
+			break;
+		default:
+			mutex_destroy(&cap_dev->lock);
+			ret = -EINVAL;
+			goto err_destroy_mutex;
+		}
+
+		cap_dev->pad.flags = MEDIA_PAD_FL_SINK;
+		ret = media_entity_pads_init(&cap_dev->vdev.entity, 1, &cap_dev->pad);
+		if (ret) {
+			mutex_destroy(&cap_dev->lock);
+			goto err_destroy_mutex;
+		}
+
+		vb2q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+		vb2q->io_modes = VB2_MMAP | VB2_DMABUF;
+		vb2q->drv_priv = cap_dev;
+		vb2q->mem_ops = &vb2_dma_contig_memops;
+		vb2q->ops = &mali_c55_vb2_ops;
+		vb2q->buf_struct_size = sizeof(struct mali_c55_buffer);
+		vb2q->min_queued_buffers = 1;
+		vb2q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+		vb2q->lock = &cap_dev->lock;
+		vb2q->dev = mali_c55->dev;
+
+		ret = vb2_queue_init(vb2q);
+		if (ret) {
+			dev_err(mali_c55->dev, "%s vb2 queue init failed\n",
+				mali_c55_cap_dev_to_name(cap_dev));
+			goto err_cleanup_media_entity;
+		}
+
+		strscpy(cap_dev->vdev.name, capture_device_names[i],
+			sizeof(cap_dev->vdev.name));
+		vdev->release = video_device_release_empty;
+		vdev->fops = &mali_c55_v4l2_fops;
+		vdev->ioctl_ops = &mali_c55_v4l2_ioctl_ops;
+		vdev->lock = &cap_dev->lock;
+		vdev->v4l2_dev = &mali_c55->v4l2_dev;
+		vdev->queue = &cap_dev->queue;
+		vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE_MPLANE |
+				    V4L2_CAP_STREAMING | V4L2_CAP_IO_MC;
+		vdev->entity.ops = &mali_c55_media_ops;
+		video_set_drvdata(vdev, cap_dev);
+
+		memset(&pix_mp, 0, sizeof(pix_mp));
+		pix_mp.pixelformat = V4L2_PIX_FMT_RGB565;
+		pix_mp.width = MALI_C55_DEFAULT_WIDTH;
+		pix_mp.height = MALI_C55_DEFAULT_HEIGHT;
+		mali_c55_set_format(cap_dev, &pix_mp);
+
+		ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
+		if (ret) {
+			dev_err(mali_c55->dev,
+				"%s failed to register video device\n",
+				mali_c55_cap_dev_to_name(cap_dev));
+			goto err_release_vb2q;
+		}
+	}
+
+	return 0;
+
+err_release_vb2q:
+	vb2_queue_release(vb2q);
+err_cleanup_media_entity:
+	media_entity_cleanup(&cap_dev->vdev.entity);
+err_destroy_mutex:
+	mutex_destroy(&cap_dev->lock);
+	mali_c55_unregister_capture_devs(mali_c55);
+
+	return ret;
+}
+
+void mali_c55_unregister_capture_devs(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_cap_dev *cap_dev;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55->cap_devs); i++) {
+		cap_dev = &mali_c55->cap_devs[i];
+
+		if (!video_is_registered(&cap_dev->vdev))
+			continue;
+
+		vb2_video_unregister_device(&cap_dev->vdev);
+		media_entity_cleanup(&cap_dev->vdev.entity);
+		mutex_destroy(&cap_dev->lock);
+	}
+}
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-common.h b/drivers/media/platform/arm/mali-c55/mali-c55-common.h
new file mode 100644
index 000000000000..3c4e3f13961b
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-common.h
@@ -0,0 +1,266 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM Mali-C55 ISP Driver - Common definitions
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#ifndef _MALI_C55_COMMON_H
+#define _MALI_C55_COMMON_H
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/scatterlist.h>
+#include <linux/videodev2.h>
+
+#include <media/media-device.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+#include <media/videobuf2-core.h>
+#include <media/videobuf2-v4l2.h>
+
+#define MALI_C55_DRIVER_NAME		"mali-c55"
+
+/* min and max values for the image sizes */
+#define MALI_C55_MIN_WIDTH		640U
+#define MALI_C55_MIN_HEIGHT		480U
+#define MALI_C55_MAX_WIDTH		8192U
+#define MALI_C55_MAX_HEIGHT		8192U
+#define MALI_C55_DEFAULT_WIDTH		1920U
+#define MALI_C55_DEFAULT_HEIGHT		1080U
+
+#define MALI_C55_DEFAULT_MEDIA_BUS_FMT	MEDIA_BUS_FMT_RGB121212_1X36
+
+struct mali_c55;
+struct mali_c55_cap_dev;
+struct platform_device;
+
+static const char * const mali_c55_clk_names[] = {
+	"aclk",
+	"hclk",
+};
+
+enum mali_c55_interrupts {
+	MALI_C55_IRQ_ISP_START,
+	MALI_C55_IRQ_ISP_DONE,
+	MALI_C55_IRQ_MCM_ERROR,
+	MALI_C55_IRQ_BROKEN_FRAME_ERROR,
+	MALI_C55_IRQ_MET_AF_DONE,
+	MALI_C55_IRQ_MET_AEXP_DONE,
+	MALI_C55_IRQ_MET_AWB_DONE,
+	MALI_C55_IRQ_AEXP_1024_DONE,
+	MALI_C55_IRQ_IRIDIX_MET_DONE,
+	MALI_C55_IRQ_LUT_INIT_DONE,
+	MALI_C55_IRQ_FR_Y_DONE,
+	MALI_C55_IRQ_FR_UV_DONE,
+	MALI_C55_IRQ_DS_Y_DONE,
+	MALI_C55_IRQ_DS_UV_DONE,
+	MALI_C55_IRQ_LINEARIZATION_DONE,
+	MALI_C55_IRQ_RAW_FRONTEND_DONE,
+	MALI_C55_IRQ_NOISE_REDUCTION_DONE,
+	MALI_C55_IRQ_IRIDIX_DONE,
+	MALI_C55_IRQ_BAYER2RGB_DONE,
+	MALI_C55_IRQ_WATCHDOG_TIMER,
+	MALI_C55_IRQ_FRAME_COLLISION,
+	MALI_C55_IRQ_UNUSED,
+	MALI_C55_IRQ_DMA_ERROR,
+	MALI_C55_IRQ_INPUT_STOPPED,
+	MALI_C55_IRQ_MET_AWB_TARGET1_HIT,
+	MALI_C55_IRQ_MET_AWB_TARGET2_HIT,
+	MALI_C55_NUM_IRQ_BITS
+};
+
+enum mali_c55_isp_pads {
+	MALI_C55_ISP_PAD_SINK_VIDEO,
+	MALI_C55_ISP_PAD_SOURCE,
+	MALI_C55_ISP_PAD_SOURCE_BYPASS,
+	MALI_C55_ISP_NUM_PADS,
+};
+
+struct mali_c55_tpg {
+	struct mali_c55 *mali_c55;
+	struct v4l2_subdev sd;
+	struct media_pad pad;
+	struct mutex lock;
+	struct mali_c55_tpg_ctrls {
+		struct v4l2_ctrl_handler handler;
+		struct v4l2_ctrl *test_pattern;
+		struct v4l2_ctrl *hblank;
+		struct v4l2_ctrl *vblank;
+	} ctrls;
+};
+
+struct mali_c55_isp {
+	struct mali_c55 *mali_c55;
+	struct v4l2_subdev sd;
+	struct media_pad pads[MALI_C55_ISP_NUM_PADS];
+	struct v4l2_subdev *source;
+	struct v4l2_async_notifier notifier;
+	struct mutex lock;
+	unsigned int frame_sequence;
+};
+
+enum mali_c55_resizer_ids {
+	MALI_C55_RZR_FR,
+	MALI_C55_RZR_DS,
+	MALI_C55_NUM_RZRS,
+};
+
+enum mali_c55_rzr_pads {
+	MALI_C55_RZR_SINK_PAD,
+	MALI_C55_RZR_SOURCE_PAD,
+	MALI_C55_RZR_SINK_BYPASS_PAD,
+	MALI_C55_RZR_NUM_PADS
+};
+
+struct mali_c55_resizer {
+	struct mali_c55 *mali_c55;
+	struct mali_c55_cap_dev *cap_dev;
+	enum mali_c55_resizer_ids id;
+	struct v4l2_subdev sd;
+	struct media_pad pads[MALI_C55_RZR_NUM_PADS];
+	unsigned int num_routes;
+	bool streaming;
+};
+
+enum mali_c55_cap_devs {
+	MALI_C55_CAP_DEV_FR,
+	MALI_C55_CAP_DEV_DS,
+	MALI_C55_NUM_CAP_DEVS
+};
+
+struct mali_c55_fmt {
+	u32 fourcc;
+	unsigned int mbus_codes[2];
+	bool is_raw;
+	struct mali_c55_fmt_registers {
+		unsigned int base_mode;
+		unsigned int uv_plane;
+	} registers;
+};
+
+enum mali_c55_isp_bayer_order {
+	MALI_C55_BAYER_ORDER_RGGB,
+	MALI_C55_BAYER_ORDER_GRBG,
+	MALI_C55_BAYER_ORDER_GBRG,
+	MALI_C55_BAYER_ORDER_BGGR
+};
+
+struct mali_c55_isp_fmt {
+	u32 code;
+	u8 bitwidth;
+	enum v4l2_pixel_encoding encoding;
+	enum mali_c55_isp_bayer_order order;
+};
+
+enum mali_c55_planes {
+	MALI_C55_PLANE_Y,
+	MALI_C55_PLANE_UV,
+	MALI_C55_NUM_PLANES
+};
+
+struct mali_c55_buffer {
+	struct vb2_v4l2_buffer vb;
+	bool plane_done[MALI_C55_NUM_PLANES];
+	struct list_head queue;
+	u32 addrs[MALI_C55_NUM_PLANES];
+};
+
+struct mali_c55_cap_dev {
+	struct mali_c55 *mali_c55;
+	struct mali_c55_resizer *rzr;
+	struct video_device vdev;
+	struct media_pad pad;
+	struct vb2_queue queue;
+	struct mutex lock;
+	unsigned int reg_offset;
+
+	struct mali_c55_mode {
+		const struct mali_c55_fmt *capture_fmt;
+		struct v4l2_pix_format_mplane pix_mp;
+	} mode;
+
+	struct {
+		spinlock_t lock;
+		struct list_head queue;
+		struct mali_c55_buffer *curr;
+		struct mali_c55_buffer *next;
+	} buffers;
+
+	bool streaming;
+};
+
+enum mali_c55_config_spaces {
+	MALI_C55_CONFIG_PING,
+	MALI_C55_CONFIG_PONG,
+	MALI_C55_NUM_CONFIG_SPACES
+};
+
+struct mali_c55_ctx {
+	struct mali_c55 *mali_c55;
+	void *registers;
+	phys_addr_t base;
+	spinlock_t lock;
+	struct list_head list;
+};
+
+struct mali_c55 {
+	struct device *dev;
+	struct resource *res;
+	void __iomem *base;
+	struct dma_chan *channel;
+	struct clk_bulk_data clks[ARRAY_SIZE(mali_c55_clk_names)];
+
+	u16 capabilities;
+	struct media_device media_dev;
+	struct v4l2_device v4l2_dev;
+	struct media_pipeline pipe;
+
+	struct mali_c55_tpg tpg;
+	struct mali_c55_isp isp;
+	struct mali_c55_resizer resizers[MALI_C55_NUM_RZRS];
+	struct mali_c55_cap_dev cap_devs[MALI_C55_NUM_CAP_DEVS];
+
+	struct list_head contexts;
+	enum mali_c55_config_spaces next_config;
+};
+
+void mali_c55_write(struct mali_c55 *mali_c55, unsigned int addr, u32 val);
+u32 mali_c55_read(struct mali_c55 *mali_c55, unsigned int addr,
+		  bool force_hardware);
+void mali_c55_update_bits(struct mali_c55 *mali_c55, unsigned int addr,
+			  u32 mask, u32 val);
+int mali_c55_config_write(struct mali_c55_ctx *ctx,
+			  enum mali_c55_config_spaces cfg_space);
+
+int mali_c55_register_isp(struct mali_c55 *mali_c55);
+int mali_c55_register_tpg(struct mali_c55 *mali_c55);
+void mali_c55_unregister_tpg(struct mali_c55 *mali_c55);
+void mali_c55_unregister_isp(struct mali_c55 *mali_c55);
+int mali_c55_register_resizers(struct mali_c55 *mali_c55);
+void mali_c55_unregister_resizers(struct mali_c55 *mali_c55);
+int mali_c55_register_capture_devs(struct mali_c55 *mali_c55);
+void mali_c55_unregister_capture_devs(struct mali_c55 *mali_c55);
+struct mali_c55_ctx *mali_c55_get_active_context(struct mali_c55 *mali_c55);
+void mali_c55_set_plane_done(struct mali_c55_cap_dev *cap_dev,
+			     enum mali_c55_planes plane);
+void mali_c55_set_next_buffer(struct mali_c55_cap_dev *cap_dev);
+void mali_c55_isp_queue_event_sof(struct mali_c55 *mali_c55);
+
+bool mali_c55_format_is_raw(unsigned int mbus_code);
+void mali_c55_rzr_start_stream(struct mali_c55_resizer *rzr);
+void mali_c55_rzr_stop_stream(struct mali_c55_resizer *rzr);
+int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable);
+
+const struct mali_c55_isp_fmt *
+mali_c55_isp_fmt_next(const struct mali_c55_isp_fmt *fmt);
+bool mali_c55_isp_is_format_supported(unsigned int mbus_code);
+#define for_each_mali_isp_fmt(fmt)\
+	for ((fmt) = NULL; ((fmt) = mali_c55_isp_fmt_next((fmt)));)
+
+#endif /* _MALI_C55_COMMON_H */
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-core.c b/drivers/media/platform/arm/mali-c55/mali-c55-core.c
new file mode 100644
index 000000000000..b30274556e75
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-core.c
@@ -0,0 +1,748 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Mali-C55 ISP Driver - Core driver code
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/ioport.h>
+#include <linux/mod_devicetable.h>
+#include <linux/of.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/scatterlist.h>
+#include <linux/string.h>
+
+#include <media/media-entity.h>
+#include <media/v4l2-device.h>
+#include <media/videobuf2-dma-contig.h>
+
+#include "mali-c55-common.h"
+#include "mali-c55-registers.h"
+
+static const char * const mali_c55_interrupt_names[] = {
+	[MALI_C55_IRQ_ISP_START] = "ISP start",
+	[MALI_C55_IRQ_ISP_DONE] = "ISP done",
+	[MALI_C55_IRQ_MCM_ERROR] = "Multi-context management error",
+	[MALI_C55_IRQ_BROKEN_FRAME_ERROR] = "Broken frame error",
+	[MALI_C55_IRQ_MET_AF_DONE] = "AF metering done",
+	[MALI_C55_IRQ_MET_AEXP_DONE] = "AEXP metering done",
+	[MALI_C55_IRQ_MET_AWB_DONE] = "AWB metering done",
+	[MALI_C55_IRQ_AEXP_1024_DONE] = "AEXP 1024-bit histogram done",
+	[MALI_C55_IRQ_IRIDIX_MET_DONE] = "Iridix metering done",
+	[MALI_C55_IRQ_LUT_INIT_DONE] = "LUT memory init done",
+	[MALI_C55_IRQ_FR_Y_DONE] = "Full resolution Y plane DMA done",
+	[MALI_C55_IRQ_FR_UV_DONE] = "Full resolution U/V plane DMA done",
+	[MALI_C55_IRQ_DS_Y_DONE] = "Downscale Y plane DMA done",
+	[MALI_C55_IRQ_DS_UV_DONE] = "Downscale U/V plane DMA done",
+	[MALI_C55_IRQ_LINEARIZATION_DONE] = "Linearisation done",
+	[MALI_C55_IRQ_RAW_FRONTEND_DONE] = "Raw frontend processing done",
+	[MALI_C55_IRQ_NOISE_REDUCTION_DONE] = "Noise reduction done",
+	[MALI_C55_IRQ_IRIDIX_DONE] = "Iridix done",
+	[MALI_C55_IRQ_BAYER2RGB_DONE] = "Bayer to RGB conversion done",
+	[MALI_C55_IRQ_WATCHDOG_TIMER] = "Watchdog timer timed out",
+	[MALI_C55_IRQ_FRAME_COLLISION] = "Frame collision error",
+	[MALI_C55_IRQ_UNUSED] = "IRQ bit unused",
+	[MALI_C55_IRQ_DMA_ERROR] = "DMA error",
+	[MALI_C55_IRQ_INPUT_STOPPED] = "Input port safely stopped",
+	[MALI_C55_IRQ_MET_AWB_TARGET1_HIT] = "AWB metering target 1 address hit",
+	[MALI_C55_IRQ_MET_AWB_TARGET2_HIT] = "AWB metering target 2 address hit"
+};
+
+static unsigned int config_space_addrs[] = {
+	[MALI_C55_CONFIG_PING] = 0x0AB6C,
+	[MALI_C55_CONFIG_PONG] = 0x22B2C,
+};
+
+/* System IO
+ *
+ * The Mali-C55 ISP has up to two configuration register spaces (called 'ping'
+ * and 'pong'), with the  expectation that the 'active' space will be left
+ * untouched whilst a frame is being processed and the 'inactive' space
+ * configured ready to be passed during the blanking period before the next
+ * frame processing starts. These spaces should ideally be set via DMA transfer
+ * from a buffer rather than through individual register set operations. There
+ * is also a shared global register space which should be set normally. Of
+ * course, the ISP might be included in a system which lacks a suitable DMA
+ * engine, and the second configuration space might not be fitted at all, which
+ * means we need to support four scenarios:
+ *
+ * 1. Multi config space, with DMA engine.
+ * 2. Multi config space, no DMA engine.
+ * 3. Single config space, with DMA engine.
+ * 4. Single config space, no DMA engine.
+ *
+ * The first case is very easy, but the rest present annoying problems. The best
+ * way to solve them seems to be simply to replicate the concept of DMAing over
+ * the configuration buffer even if there's no DMA engine on the board, for
+ * which we rely on memcpy. To facilitate this any read/write call that is made
+ * to an address within those config spaces should infact be directed to a
+ * buffer that was allocated to hold them rather than the IO memory itself. The
+ * actual copy of that buffer to IO mem will happen on interrupt.
+ */
+
+void mali_c55_write(struct mali_c55 *mali_c55, unsigned int addr, u32 val)
+{
+	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
+
+	if (addr >= MALI_C55_REG_CONFIG_SPACES_OFFSET) {
+		spin_lock(&ctx->lock);
+		addr = (addr - MALI_C55_REG_CONFIG_SPACES_OFFSET) / 4;
+		((u32 *)ctx->registers)[addr] = val;
+		spin_unlock(&ctx->lock);
+
+		return;
+	}
+
+	writel(val, mali_c55->base + addr);
+}
+
+u32 mali_c55_read(struct mali_c55 *mali_c55, unsigned int addr,
+		  bool force_hardware)
+{
+	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
+	u32 val;
+
+	if (addr >= MALI_C55_REG_CONFIG_SPACES_OFFSET && !force_hardware) {
+		spin_lock(&ctx->lock);
+		addr = (addr - MALI_C55_REG_CONFIG_SPACES_OFFSET) / 4;
+		val = ((u32 *)ctx->registers)[addr];
+		spin_unlock(&ctx->lock);
+
+		return val;
+	}
+
+	return readl(mali_c55->base + addr);
+}
+
+void mali_c55_update_bits(struct mali_c55 *mali_c55, unsigned int addr,
+			  u32 mask, u32 val)
+{
+	u32 orig, tmp;
+
+	orig = mali_c55_read(mali_c55, addr, false);
+
+	tmp = orig & ~mask;
+	tmp |= (val << (ffs(mask) - 1)) & mask;
+
+	if (tmp != orig)
+		mali_c55_write(mali_c55, addr, tmp);
+}
+
+static int mali_c55_dma_xfer(struct mali_c55_ctx *ctx, dma_addr_t src,
+			     dma_addr_t dst, enum dma_data_direction dir)
+{
+	struct mali_c55 *mali_c55 = ctx->mali_c55;
+	struct dma_async_tx_descriptor *tx;
+	enum dma_status status;
+	dma_cookie_t cookie;
+
+	tx = dmaengine_prep_dma_memcpy(mali_c55->channel, dst, src,
+				       MALI_C55_CONFIG_SPACE_SIZE, 0);
+	if (!tx) {
+		dev_err(mali_c55->dev, "failed to prep DMA memcpy\n");
+		return -EIO;
+	}
+
+	cookie = dmaengine_submit(tx);
+	if (dma_submit_error(cookie)) {
+		dev_err(mali_c55->dev, "error submitting dma transfer\n");
+		return -EIO;
+	}
+
+	status = dma_sync_wait(mali_c55->channel, cookie);
+	if (status != DMA_COMPLETE) {
+		dev_err(mali_c55->dev, "dma transfer failed\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int mali_c55_dma_read(struct mali_c55_ctx *ctx,
+			     enum mali_c55_config_spaces cfg_space)
+{
+	struct mali_c55 *mali_c55 = ctx->mali_c55;
+	struct device *dma_dev = mali_c55->channel->device->dev;
+	dma_addr_t src = ctx->base + config_space_addrs[cfg_space];
+	dma_addr_t dst;
+	int ret;
+
+	guard(spinlock)(&ctx->lock);
+
+	dst = dma_map_single(dma_dev, ctx->registers,
+			     MALI_C55_CONFIG_SPACE_SIZE, DMA_FROM_DEVICE);
+	if (dma_mapping_error(dma_dev, dst)) {
+		dev_err(mali_c55->dev, "failed to map DMA addr\n");
+		return -EIO;
+	}
+
+	ret = mali_c55_dma_xfer(ctx, src, dst, DMA_FROM_DEVICE);
+	dma_unmap_single(dma_dev, dst, MALI_C55_CONFIG_SPACE_SIZE,
+			 DMA_FROM_DEVICE);
+
+	return ret;
+}
+
+static int mali_c55_dma_write(struct mali_c55_ctx *ctx,
+		       enum mali_c55_config_spaces cfg_space)
+{
+	struct mali_c55 *mali_c55 = ctx->mali_c55;
+	struct device *dma_dev = mali_c55->channel->device->dev;
+	dma_addr_t dst = ctx->base + config_space_addrs[cfg_space];
+	dma_addr_t src;
+	int ret;
+
+	guard(spinlock)(&ctx->lock);
+
+	src = dma_map_single(dma_dev, ctx->registers,
+			     MALI_C55_CONFIG_SPACE_SIZE, DMA_TO_DEVICE);
+	if (dma_mapping_error(dma_dev, src)) {
+		dev_err(mali_c55->dev, "failed to map DMA addr\n");
+		return -EIO;
+	}
+
+	ret = mali_c55_dma_xfer(ctx, src, dst, DMA_TO_DEVICE);
+	dma_unmap_single(dma_dev, src, MALI_C55_CONFIG_SPACE_SIZE,
+			 DMA_TO_DEVICE);
+
+	return ret;
+}
+
+static int mali_c55_config_read(struct mali_c55_ctx *ctx,
+				enum mali_c55_config_spaces cfg_space)
+{
+	struct mali_c55 *mali_c55 = ctx->mali_c55;
+
+	if (mali_c55->channel) {
+		return mali_c55_dma_read(ctx, cfg_space);
+	} else {
+		memcpy_fromio(ctx->registers,
+			      mali_c55->base + config_space_addrs[cfg_space],
+			      MALI_C55_CONFIG_SPACE_SIZE);
+		return 0;
+	}
+}
+
+int mali_c55_config_write(struct mali_c55_ctx *ctx,
+			  enum mali_c55_config_spaces cfg_space)
+{
+	struct mali_c55 *mali_c55 = ctx->mali_c55;
+
+	if (mali_c55->channel) {
+		return mali_c55_dma_write(ctx, cfg_space);
+	} else {
+		memcpy_toio(mali_c55->base + config_space_addrs[cfg_space],
+			    ctx->registers, MALI_C55_CONFIG_SPACE_SIZE);
+		return 0;
+	}
+}
+
+struct mali_c55_ctx *mali_c55_get_active_context(struct mali_c55 *mali_c55)
+{
+	return list_first_entry(&mali_c55->contexts, struct mali_c55_ctx, list);
+}
+
+static void mali_c55_remove_links(struct mali_c55 *mali_c55)
+{
+	unsigned int i;
+
+	media_entity_remove_links(&mali_c55->tpg.sd.entity);
+	media_entity_remove_links(&mali_c55->isp.sd.entity);
+
+	for (i = 0; i < MALI_C55_NUM_RZRS; i++)
+		media_entity_remove_links(&mali_c55->resizers[i].sd.entity);
+
+	for (i = 0; i < MALI_C55_NUM_CAP_DEVS; i++)
+		media_entity_remove_links(&mali_c55->cap_devs[i].vdev.entity);
+}
+
+static int mali_c55_create_links(struct mali_c55 *mali_c55)
+{
+	int ret;
+
+	/* Test pattern generator to ISP */
+	ret = media_create_pad_link(&mali_c55->tpg.sd.entity, 0,
+				    &mali_c55->isp.sd.entity,
+				    MALI_C55_ISP_PAD_SINK_VIDEO, 0);
+	if (ret) {
+		dev_err(mali_c55->dev, "failed to link TPG and ISP\n");
+		goto err_remove_links;
+	}
+
+	/* Full resolution resizer pipe. */
+	ret = media_create_pad_link(&mali_c55->isp.sd.entity,
+			MALI_C55_ISP_PAD_SOURCE,
+			&mali_c55->resizers[MALI_C55_RZR_FR].sd.entity,
+			MALI_C55_RZR_SINK_PAD,
+			MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+	if (ret) {
+		dev_err(mali_c55->dev, "failed to link ISP and FR resizer\n");
+		goto err_remove_links;
+	}
+
+	/* Full resolution bypass. */
+	ret = media_create_pad_link(&mali_c55->isp.sd.entity,
+				    MALI_C55_ISP_PAD_SOURCE_BYPASS,
+				    &mali_c55->resizers[MALI_C55_RZR_FR].sd.entity,
+				    MALI_C55_RZR_SINK_BYPASS_PAD,
+				    MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+	if (ret) {
+		dev_err(mali_c55->dev, "failed to link ISP and FR resizer\n");
+		goto err_remove_links;
+	}
+
+	/* Resizer pipe to video capture nodes. */
+	ret = media_create_pad_link(&mali_c55->resizers[0].sd.entity,
+			MALI_C55_RZR_SOURCE_PAD,
+			&mali_c55->cap_devs[MALI_C55_CAP_DEV_FR].vdev.entity,
+			0, MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+	if (ret) {
+		dev_err(mali_c55->dev,
+			"failed to link FR resizer and video device\n");
+		goto err_remove_links;
+	}
+
+	/* The downscale pipe is an optional hardware block */
+	if (mali_c55->capabilities & MALI_C55_GPS_DS_PIPE_FITTED) {
+		ret = media_create_pad_link(&mali_c55->isp.sd.entity,
+			MALI_C55_ISP_PAD_SOURCE,
+			&mali_c55->resizers[MALI_C55_RZR_DS].sd.entity,
+			MALI_C55_RZR_SINK_PAD,
+			MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+		if (ret) {
+			dev_err(mali_c55->dev,
+				"failed to link ISP and DS resizer\n");
+			goto err_remove_links;
+		}
+
+		ret = media_create_pad_link(&mali_c55->resizers[1].sd.entity,
+			MALI_C55_RZR_SOURCE_PAD,
+			&mali_c55->cap_devs[MALI_C55_CAP_DEV_DS].vdev.entity,
+			0, MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+		if (ret) {
+			dev_err(mali_c55->dev,
+				"failed to link DS resizer and video device\n");
+			goto err_remove_links;
+		}
+	}
+
+	return 0;
+
+err_remove_links:
+	mali_c55_remove_links(mali_c55);
+	return ret;
+}
+
+static void mali_c55_unregister_entities(struct mali_c55 *mali_c55)
+{
+	mali_c55_unregister_tpg(mali_c55);
+	mali_c55_unregister_isp(mali_c55);
+	mali_c55_unregister_resizers(mali_c55);
+	mali_c55_unregister_capture_devs(mali_c55);
+}
+
+static int mali_c55_register_entities(struct mali_c55 *mali_c55)
+{
+	int ret;
+
+	ret = mali_c55_register_tpg(mali_c55);
+	if (ret)
+		return ret;
+
+	ret = mali_c55_register_isp(mali_c55);
+	if (ret)
+		goto err_unregister_entities;
+
+	ret = mali_c55_register_resizers(mali_c55);
+	if (ret)
+		goto err_unregister_entities;
+
+	ret = mali_c55_register_capture_devs(mali_c55);
+	if (ret)
+		goto err_unregister_entities;
+
+	ret = mali_c55_create_links(mali_c55);
+	if (ret)
+		goto err_unregister_entities;
+
+	return 0;
+
+err_unregister_entities:
+	mali_c55_unregister_entities(mali_c55);
+
+	return ret;
+}
+
+static u32 mali_c55_check_hwcfg(struct mali_c55 *mali_c55)
+{
+	u32 product, version, revision, capabilities;
+
+	product = mali_c55_read(mali_c55, MALI_C55_REG_PRODUCT, false);
+	version = mali_c55_read(mali_c55, MALI_C55_REG_VERSION, false);
+	revision = mali_c55_read(mali_c55, MALI_C55_REG_REVISION, false);
+
+	dev_info(mali_c55->dev, "Detected Mali-C55 ISP %u.%u.%u\n",
+		 product, version, revision);
+
+	capabilities = mali_c55_read(mali_c55,
+				     MALI_C55_REG_GLOBAL_PARAMETER_STATUS,
+				     false);
+	mali_c55->capabilities = (capabilities & 0xffff);
+
+	/* TODO: Might as well start some debugfs */
+	dev_info(mali_c55->dev, "Mali-C55 capabilities: 0x%04x\n", capabilities);
+	return version;
+}
+
+static void mali_c55_swap_next_config(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
+	u32 curr_config, next_config;
+
+	curr_config = mali_c55_read(mali_c55, MALI_C55_REG_PING_PONG_READ, false);
+	curr_config = (curr_config & MALI_C55_REG_PING_PONG_READ_MASK) >> 2;
+	next_config = ~curr_config & 1;
+
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_MCU_CONFIG,
+			     MALI_C55_REG_MCU_CONFIG_WRITE_MASK, next_config);
+	mali_c55_config_write(ctx, next_config ?
+			      MALI_C55_CONFIG_PING : MALI_C55_CONFIG_PONG);
+}
+
+static irqreturn_t mali_c55_isr(int irq, void *context)
+{
+	struct device *dev = context;
+	struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
+	u32 interrupt_status;
+	unsigned int i, j;
+
+	interrupt_status = mali_c55_read(mali_c55,
+					 MALI_C55_REG_INTERRUPT_STATUS_VECTOR,
+					 false);
+	if (!interrupt_status)
+		return IRQ_NONE;
+
+	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_CLEAR_VECTOR,
+		       interrupt_status);
+	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_CLEAR, 0);
+	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_CLEAR, 1);
+
+	for (i = 0; i < MALI_C55_NUM_IRQ_BITS; i++) {
+		if (!(interrupt_status & (1 << i)))
+			continue;
+
+		switch (i) {
+		case MALI_C55_IRQ_ISP_START:
+			mali_c55_isp_queue_event_sof(mali_c55);
+
+			for (j = i; j < MALI_C55_NUM_CAP_DEVS; j++)
+				mali_c55_set_next_buffer(&mali_c55->cap_devs[j]);
+
+			mali_c55_swap_next_config(mali_c55);
+
+			break;
+		case MALI_C55_IRQ_ISP_DONE:
+			/*
+			 * TODO: Where the ISP has no Pong config fitted, we'd
+			 * have to do the mali_c55_swap_next_config() call here.
+			 */
+			mali_c55->isp.frame_sequence++;
+			break;
+		case MALI_C55_IRQ_FR_Y_DONE:
+			mali_c55_set_plane_done(
+				&mali_c55->cap_devs[MALI_C55_CAP_DEV_FR],
+				MALI_C55_PLANE_Y);
+			break;
+		case MALI_C55_IRQ_FR_UV_DONE:
+			mali_c55_set_plane_done(
+				&mali_c55->cap_devs[MALI_C55_CAP_DEV_FR],
+				MALI_C55_PLANE_UV);
+			break;
+		case MALI_C55_IRQ_DS_Y_DONE:
+			mali_c55_set_plane_done(
+				&mali_c55->cap_devs[MALI_C55_CAP_DEV_DS],
+				MALI_C55_PLANE_Y);
+			break;
+		case MALI_C55_IRQ_DS_UV_DONE:
+			mali_c55_set_plane_done(
+				&mali_c55->cap_devs[MALI_C55_CAP_DEV_DS],
+				MALI_C55_PLANE_UV);
+			break;
+		default:
+			/*
+			 * Only the above interrupts are currently unmasked. If
+			 * we receive anything else here then something weird
+			 * has gone on.
+			 */
+			dev_err(dev, "masked interrupt %s triggered\n",
+				mali_c55_interrupt_names[i]);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int mali_c55_init_context(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_ctx *ctx;
+	int ret;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx) {
+		dev_err(mali_c55->dev, "failed to allocate new context\n");
+		return -ENOMEM;
+	}
+
+	ctx->base = mali_c55->res->start;
+	ctx->mali_c55 = mali_c55;
+
+	ctx->registers = kzalloc(MALI_C55_CONFIG_SPACE_SIZE,
+				 GFP_KERNEL | GFP_DMA);
+	if (!ctx->registers) {
+		ret = -ENOMEM;
+		goto err_free_ctx;
+	}
+
+	/*
+	 * The allocated memory is empty, we need to load the default
+	 * register settings. We just read Ping; it's identical to Pong.
+	 */
+	ret = mali_c55_config_read(ctx, MALI_C55_CONFIG_PING);
+	if (ret)
+		goto err_free_registers;
+
+	list_add_tail(&ctx->list, &mali_c55->contexts);
+
+	return 0;
+
+err_free_registers:
+	kfree(ctx->registers);
+err_free_ctx:
+	kfree(ctx);
+
+	return ret;
+}
+
+static int mali_c55_runtime_resume(struct device *dev)
+{
+	struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_bulk_prepare_enable(ARRAY_SIZE(mali_c55->clks),
+				      mali_c55->clks);
+	if (ret)
+		dev_err(mali_c55->dev, "failed to enable clocks\n");
+
+	return ret;
+}
+
+static int mali_c55_runtime_suspend(struct device *dev)
+{
+	struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
+
+	clk_bulk_disable_unprepare(ARRAY_SIZE(mali_c55->clks), mali_c55->clks);
+	return 0;
+}
+
+static const struct dev_pm_ops mali_c55_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(mali_c55_runtime_suspend, mali_c55_runtime_resume,
+			   NULL)
+};
+
+static int mali_c55_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mali_c55 *mali_c55;
+	dma_cap_mask_t mask;
+	u32 version;
+	int ret;
+	u32 val;
+
+	mali_c55 = devm_kzalloc(dev, sizeof(*mali_c55), GFP_KERNEL);
+	if (!mali_c55)
+		return dev_err_probe(dev, -ENOMEM,
+				     "failed to allocate memory\n");
+
+	mali_c55->dev = dev;
+	platform_set_drvdata(pdev, mali_c55);
+
+	mali_c55->base = devm_platform_get_and_ioremap_resource(pdev, 0,
+								&mali_c55->res);
+	if (IS_ERR(mali_c55->base))
+		return dev_err_probe(dev, PTR_ERR(mali_c55->base),
+				     "failed to map IO memory\n");
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to get interrupt num\n");
+
+	ret = devm_request_threaded_irq(&pdev->dev, ret, NULL,
+					mali_c55_isr, IRQF_ONESHOT,
+					dev_driver_string(&pdev->dev),
+					&pdev->dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to request irq\n");
+
+	for (unsigned int i = 0; i < ARRAY_SIZE(mali_c55_clk_names); i++)
+		mali_c55->clks[i].id = mali_c55_clk_names[i];
+
+	ret = devm_clk_bulk_get(dev, ARRAY_SIZE(mali_c55->clks), mali_c55->clks);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to acquire clocks\n");
+
+	pm_runtime_enable(&pdev->dev);
+
+	ret = pm_runtime_resume_and_get(&pdev->dev);
+	if (ret)
+		goto err_pm_runtime_disable;
+
+	of_reserved_mem_device_init(dev);
+	version = mali_c55_check_hwcfg(mali_c55);
+	vb2_dma_contig_set_max_seg_size(dev, UINT_MAX);
+
+	/* Use "software only" context management. */
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_MCU_CONFIG,
+			     MALI_C55_REG_MCU_CONFIG_OVERRIDE_MASK,
+			     MALI_C55_REG_MCU_CONFIG_OVERRIDE_MASK);
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_MEMCPY, mask);
+
+	/*
+	 * No error check, because we will just fallback on memcpy if there is
+	 * no usable DMA channel on the system.
+	 */
+	mali_c55->channel = dma_request_channel(mask, NULL, NULL);
+
+	INIT_LIST_HEAD(&mali_c55->contexts);
+	ret = mali_c55_init_context(mali_c55);
+	if (ret)
+		goto err_release_dma_channel;
+
+	mali_c55->media_dev.dev = dev;
+	strscpy(mali_c55->media_dev.model, "ARM Mali-C55 ISP",
+		sizeof(mali_c55->media_dev.model));
+	mali_c55->media_dev.hw_revision = version;
+
+	media_device_init(&mali_c55->media_dev);
+	ret = media_device_register(&mali_c55->media_dev);
+	if (ret)
+		goto err_cleanup_media_device;
+
+	mali_c55->v4l2_dev.mdev = &mali_c55->media_dev;
+	ret = v4l2_device_register(dev, &mali_c55->v4l2_dev);
+	if (ret) {
+		dev_err(dev, "failed to register V4L2 device\n");
+		goto err_unregister_media_device;
+	};
+
+	ret = mali_c55_register_entities(mali_c55);
+	if (ret) {
+		dev_err(dev, "failed to register entities\n");
+		goto err_unregister_v4l2_device;
+	}
+
+	/* Set safe stop to ensure we're in a non-streaming state */
+	mali_c55_write(mali_c55, MALI_C55_REG_INPUT_MODE_REQUEST,
+		       MALI_C55_INPUT_SAFE_STOP);
+	readl_poll_timeout(mali_c55->base + MALI_C55_REG_MODE_STATUS,
+			   val, !val, 10 * USEC_PER_MSEC, 250 * USEC_PER_MSEC);
+
+	/*
+	 * For now, few of the ISP's features are supported (pretty much just
+	 * debayering and the colour space conversion). Flag the others as being
+	 * bypassed so that they don't interfere.
+	 *
+	 * TODO: Support more features!
+	 */
+	mali_c55_write(mali_c55, 0x18eac, 0x3c);
+	mali_c55_write(mali_c55, 0x18eb0, 0xf);
+	mali_c55_write(mali_c55, 0x18eb8, 0x3);
+	mali_c55_write(mali_c55, 0x18ebc, 0x7b);
+	mali_c55_write(mali_c55, 0x18ec0, 0x38);
+	mali_c55_write(mali_c55, MALI_C55_REG_FR_BYPASS, 0xf);
+	mali_c55_write(mali_c55, MALI_C55_REG_DS_BYPASS, 0xf);
+
+	/*
+	 * We're ready to process interrupts. Clear any that are set and then
+	 * unmask them for processing.
+	 */
+	mali_c55_write(mali_c55, 0x30, 0xffffffff);
+	mali_c55_write(mali_c55, 0x34, 0xffffffff);
+	mali_c55_write(mali_c55, 0x40, 0x01);
+	mali_c55_write(mali_c55, 0x40, 0x00);
+	mali_c55_write(mali_c55, MALI_C55_REG_INTERRUPT_MASK_VECTOR, 0x39fc3fc);
+
+	pm_runtime_put(&pdev->dev);
+
+	return 0;
+
+err_unregister_v4l2_device:
+	v4l2_device_unregister(&mali_c55->v4l2_dev);
+err_unregister_media_device:
+	media_device_unregister(&mali_c55->media_dev);
+err_cleanup_media_device:
+	media_device_cleanup(&mali_c55->media_dev);
+err_release_dma_channel:
+	dma_release_channel(mali_c55->channel);
+err_pm_runtime_disable:
+	pm_runtime_disable(&pdev->dev);
+
+	return ret;
+}
+
+static void mali_c55_remove(struct platform_device *pdev)
+{
+	struct mali_c55 *mali_c55 = platform_get_drvdata(pdev);
+	struct mali_c55_ctx *ctx, *tmp;
+
+	list_for_each_entry_safe(ctx, tmp, &mali_c55->contexts, list) {
+		list_del(&ctx->list);
+		kfree(ctx->registers);
+		kfree(ctx);
+	}
+
+	mali_c55_remove_links(mali_c55);
+	mali_c55_unregister_entities(mali_c55);
+	v4l2_device_put(&mali_c55->v4l2_dev);
+	media_device_unregister(&mali_c55->media_dev);
+	media_device_cleanup(&mali_c55->media_dev);
+	dma_release_channel(mali_c55->channel);
+}
+
+static const struct of_device_id mali_c55_of_match[] = {
+	{
+		.compatible = "arm,mali-c55",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mali_c55_of_match);
+
+static struct platform_driver mali_c55_driver = {
+	.driver = {
+		.name = "mali-c55",
+		.of_match_table = of_match_ptr(mali_c55_of_match),
+		.pm = &mali_c55_pm_ops,
+	},
+	.probe = mali_c55_probe,
+	.remove_new = mali_c55_remove,
+};
+
+module_platform_driver(mali_c55_driver);
+MODULE_AUTHOR("Daniel Scally <[e-mail]>");
+MODULE_AUTHOR("Jacopo Mondi <[e-mail]>");
+MODULE_DESCRIPTION("ARM Mali-C55 ISP platform driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-isp.c b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
new file mode 100644
index 000000000000..a41b02882c50
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
@@ -0,0 +1,701 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Mali-C55 ISP Driver - Image signal processor
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <linux/property.h>
+#include <linux/string.h>
+
+#include <media/media-entity.h>
+#include <media/v4l2-common.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-mc.h>
+#include <media/v4l2-subdev.h>
+
+#include "mali-c55-common.h"
+#include "mali-c55-registers.h"
+
+static const struct mali_c55_isp_fmt mali_c55_isp_fmts[] = {
+	{
+		.code = MEDIA_BUS_FMT_SRGGB8_1X8,
+		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
+		.order = MALI_C55_BAYER_ORDER_RGGB,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGRBG8_1X8,
+		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
+		.order = MALI_C55_BAYER_ORDER_GRBG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGBRG8_1X8,
+		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
+		.order = MALI_C55_BAYER_ORDER_GBRG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SBGGR8_1X8,
+		.bitwidth = MALI_C55_INPUT_WIDTH_8BIT,
+		.order = MALI_C55_BAYER_ORDER_BGGR,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SRGGB10_1X10,
+		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
+		.order = MALI_C55_BAYER_ORDER_RGGB,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
+		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
+		.order = MALI_C55_BAYER_ORDER_GRBG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGBRG10_1X10,
+		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
+		.order = MALI_C55_BAYER_ORDER_GBRG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SBGGR10_1X10,
+		.bitwidth = MALI_C55_INPUT_WIDTH_10BIT,
+		.order = MALI_C55_BAYER_ORDER_BGGR,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SRGGB12_1X12,
+		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
+		.order = MALI_C55_BAYER_ORDER_RGGB,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGRBG12_1X12,
+		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
+		.order = MALI_C55_BAYER_ORDER_GRBG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGBRG12_1X12,
+		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
+		.order = MALI_C55_BAYER_ORDER_GBRG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SBGGR12_1X12,
+		.bitwidth = MALI_C55_INPUT_WIDTH_12BIT,
+		.order = MALI_C55_BAYER_ORDER_BGGR,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SRGGB14_1X14,
+		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
+		.order = MALI_C55_BAYER_ORDER_RGGB,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGRBG14_1X14,
+		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
+		.order = MALI_C55_BAYER_ORDER_GRBG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGBRG14_1X14,
+		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
+		.order = MALI_C55_BAYER_ORDER_GBRG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SBGGR14_1X14,
+		.bitwidth = MALI_C55_INPUT_WIDTH_14BIT,
+		.order = MALI_C55_BAYER_ORDER_BGGR,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SRGGB16_1X16,
+		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
+		.order = MALI_C55_BAYER_ORDER_RGGB,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGRBG16_1X16,
+		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
+		.order = MALI_C55_BAYER_ORDER_GRBG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SGBRG16_1X16,
+		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
+		.order = MALI_C55_BAYER_ORDER_GBRG,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_SBGGR16_1X16,
+		.bitwidth = MALI_C55_INPUT_WIDTH_16BIT,
+		.order = MALI_C55_BAYER_ORDER_BGGR,
+		.encoding = V4L2_PIXEL_ENC_BAYER,
+	},
+	{
+		.code = MEDIA_BUS_FMT_RGB202020_1X60,
+		.bitwidth = MALI_C55_INPUT_WIDTH_20BIT,
+		.order = 0, /* Not relevant for this format */
+		.encoding = V4L2_PIXEL_ENC_RGB,
+	}
+	/*
+	 * TODO: Support MEDIA_BUS_FMT_YUV20_1X60 here. This is so that we can
+	 * also support YUV input from a sensor passed-through to the output. At
+	 * present we have no mechanism to test that though so it may have to
+	 * wait a while...
+	 */
+};
+
+const struct mali_c55_isp_fmt *
+mali_c55_isp_fmt_next(const struct mali_c55_isp_fmt *fmt)
+{
+	if (!fmt)
+		fmt = &mali_c55_isp_fmts[0];
+	else
+		fmt++;
+
+	for (; fmt < &mali_c55_isp_fmts[ARRAY_SIZE(mali_c55_isp_fmts)]; fmt++)
+		return fmt;
+
+	return NULL;
+}
+
+bool mali_c55_isp_is_format_supported(unsigned int mbus_code)
+{
+	const struct mali_c55_isp_fmt *isp_fmt;
+
+	for_each_mali_isp_fmt(isp_fmt) {
+		if (isp_fmt->code == mbus_code)
+			return true;
+	}
+
+	return false;
+}
+
+static const struct mali_c55_isp_fmt *
+mali_c55_isp_get_mbus_config_by_code(u32 code)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55_isp_fmts); i++) {
+		if (mali_c55_isp_fmts[i].code == code)
+			return &mali_c55_isp_fmts[i];
+	}
+
+	return NULL;
+}
+
+static void mali_c55_isp_stop(struct mali_c55 *mali_c55)
+{
+	u32 val;
+
+	mali_c55_write(mali_c55, MALI_C55_REG_INPUT_MODE_REQUEST, MALI_C55_INPUT_SAFE_STOP);
+	readl_poll_timeout(mali_c55->base + MALI_C55_REG_MODE_STATUS,
+			   val, !val, 10 * USEC_PER_MSEC, 250 * USEC_PER_MSEC);
+}
+
+static int mali_c55_isp_start(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_ctx *ctx = mali_c55_get_active_context(mali_c55);
+	const struct mali_c55_isp_fmt *cfg;
+	struct v4l2_mbus_framefmt *format;
+	struct v4l2_subdev_state *state;
+	struct v4l2_rect *crop;
+	struct v4l2_subdev *sd;
+	u32 val;
+	int ret;
+
+	sd = &mali_c55->isp.sd;
+
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_MCU_CONFIG,
+			     MALI_C55_REG_MCU_CONFIG_WRITE_MASK, 0x01);
+
+	/* Apply input windowing */
+	state = v4l2_subdev_get_locked_active_state(sd);
+	crop = v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
+	format = v4l2_subdev_state_get_format(state,
+					      MALI_C55_ISP_PAD_SINK_VIDEO);
+	cfg = mali_c55_isp_get_mbus_config_by_code(format->code);
+
+	mali_c55_write(mali_c55, MALI_C55_REG_HC_START,
+		       MALI_C55_HC_START(crop->left));
+	mali_c55_write(mali_c55, MALI_C55_REG_HC_SIZE,
+		       MALI_C55_HC_SIZE(crop->width));
+	mali_c55_write(mali_c55, MALI_C55_REG_VC_START_SIZE,
+		       MALI_C55_VC_START(crop->top) |
+		       MALI_C55_VC_SIZE(crop->height));
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_BASE_ADDR,
+			     MALI_C55_REG_ACTIVE_WIDTH_MASK, format->width);
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_BASE_ADDR,
+			     MALI_C55_REG_ACTIVE_HEIGHT_MASK, format->height);
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_BAYER_ORDER,
+			     MALI_C55_BAYER_ORDER_MASK, cfg->order);
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_INPUT_WIDTH,
+			     MALI_C55_INPUT_WIDTH_MASK, cfg->bitwidth);
+
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
+			     MALI_C55_ISP_RAW_BYPASS_BYPASS_MASK,
+			     cfg->encoding == V4L2_PIXEL_ENC_RGB ?
+			     MALI_C55_ISP_RAW_BYPASS_BYPASS_MASK : 0x00);
+
+	ret = mali_c55_config_write(ctx, MALI_C55_CONFIG_PING);
+	if (ret) {
+		dev_err(mali_c55->dev, "failed to DMA config\n");
+		return ret;
+	}
+
+	mali_c55_write(mali_c55, MALI_C55_REG_INPUT_MODE_REQUEST,
+		       MALI_C55_INPUT_SAFE_START);
+	readl_poll_timeout(mali_c55->base + MALI_C55_REG_MODE_STATUS,
+			   val, !val, 10 * USEC_PER_MSEC, 250 * USEC_PER_MSEC);
+
+	return 0;
+}
+
+int mali_c55_isp_s_stream(struct mali_c55_isp *isp, int enable)
+{
+	struct mali_c55 *mali_c55 = isp->mali_c55;
+	struct media_pad *source_pad;
+	struct media_pad *sink_pad;
+	int ret;
+
+	if (!enable) {
+		if (isp->source)
+			v4l2_subdev_call(isp->source, video, s_stream, false);
+		isp->source = NULL;
+
+		mali_c55_isp_stop(mali_c55);
+
+		return 0;
+	}
+
+	sink_pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
+	source_pad = media_pad_remote_pad_unique(sink_pad);
+	if (IS_ERR(source_pad)) {
+		dev_err(mali_c55->dev, "Failed to get source for ISP\n");
+		return PTR_ERR(source_pad);
+	}
+
+	isp->source = media_entity_to_v4l2_subdev(source_pad->entity);
+
+	isp->frame_sequence = 0;
+	ret = mali_c55_isp_start(mali_c55);
+	if (ret) {
+		dev_err(mali_c55->dev, "Failed to start ISP\n");
+		isp->source = NULL;
+		return ret;
+	}
+
+	ret = v4l2_subdev_call(isp->source, video, s_stream, true);
+	if (ret) {
+		dev_err(mali_c55->dev, "Failed to start ISP source\n");
+		mali_c55_isp_stop(mali_c55);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int mali_c55_isp_enum_mbus_code(struct v4l2_subdev *sd,
+				       struct v4l2_subdev_state *state,
+				       struct v4l2_subdev_mbus_code_enum *code)
+{
+	/*
+	 * Only the internal RGB processed format is allowed on the regular
+	 * processing source pad.
+	 */
+	if (code->pad == MALI_C55_ISP_PAD_SOURCE) {
+		if (code->index)
+			return -EINVAL;
+
+		code->code = MEDIA_BUS_FMT_RGB121212_1X36;
+		return 0;
+	}
+
+	/* On the sink and bypass pads all the supported formats are allowed. */
+	if (code->index >= ARRAY_SIZE(mali_c55_isp_fmts))
+		return -EINVAL;
+
+	code->code = mali_c55_isp_fmts[code->index].code;
+
+	return 0;
+}
+
+static int mali_c55_isp_enum_frame_size(struct v4l2_subdev *sd,
+					struct v4l2_subdev_state *state,
+					struct v4l2_subdev_frame_size_enum *fse)
+{
+	const struct mali_c55_isp_fmt *cfg;
+
+	if (fse->index > 0)
+		return -EINVAL;
+
+	/*
+	 * Only the internal RGB processed format is allowed on the regular
+	 * processing source pad.
+	 *
+	 * On the sink and bypass pads all the supported formats are allowed.
+	 */
+	if (fse->pad == MALI_C55_ISP_PAD_SOURCE) {
+		if (fse->code != MEDIA_BUS_FMT_RGB121212_1X36)
+			return -EINVAL;
+	} else {
+		cfg = mali_c55_isp_get_mbus_config_by_code(fse->code);
+		if (!cfg)
+			return -EINVAL;
+	}
+
+	fse->min_width = MALI_C55_MIN_WIDTH;
+	fse->min_height = MALI_C55_MIN_HEIGHT;
+	fse->max_width = MALI_C55_MAX_WIDTH;
+	fse->max_height = MALI_C55_MAX_HEIGHT;
+
+	return 0;
+}
+
+static int mali_c55_isp_set_fmt(struct v4l2_subdev *sd,
+				struct v4l2_subdev_state *state,
+				struct v4l2_subdev_format *format)
+{
+	struct v4l2_mbus_framefmt *fmt = &format->format;
+	const struct mali_c55_isp_fmt *cfg;
+	struct v4l2_mbus_framefmt *src_fmt;
+	struct v4l2_rect *crop;
+
+	/*
+	 * Disallow set_fmt on the source pads; format is fixed and the sizes
+	 * are the result of applying the sink crop rectangle to the sink
+	 * format.
+	 */
+	if (format->pad)
+		return v4l2_subdev_get_fmt(sd, state, format);
+
+	cfg = mali_c55_isp_get_mbus_config_by_code(fmt->code);
+	if (!cfg)
+		fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
+	fmt->field = V4L2_FIELD_NONE;
+
+	/*
+	 * Clamp sizes in the accepted limits and clamp the crop rectangle in
+	 * the new sizes.
+	 */
+	clamp_t(unsigned int, fmt->width,
+		MALI_C55_MIN_WIDTH, MALI_C55_MAX_WIDTH);
+	clamp_t(unsigned int, fmt->width,
+		MALI_C55_MIN_HEIGHT, MALI_C55_MAX_HEIGHT);
+
+	*v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SINK_VIDEO) = *fmt;
+
+	crop = v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
+	crop->left = 0;
+	crop->top = 0;
+	crop->width = fmt->width;
+	crop->height = fmt->height;
+
+	/*
+	 * Propagate format to source pads. On the 'regular' output pad use
+	 * the internal RGB processed format, while on the bypass pad simply
+	 * replicate the ISP sink format. The sizes on both pads are the same as
+	 * the ISP sink crop rectangle.
+	 */
+	src_fmt = v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SOURCE);
+	src_fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
+	src_fmt->width = crop->width;
+	src_fmt->height = crop->height;
+
+	src_fmt = v4l2_subdev_state_get_format(state,
+					       MALI_C55_ISP_PAD_SOURCE_BYPASS);
+	src_fmt->code = fmt->code;
+	src_fmt->width = crop->width;
+	src_fmt->height = crop->height;
+
+	return 0;
+}
+
+static int mali_c55_isp_get_selection(struct v4l2_subdev *sd,
+				      struct v4l2_subdev_state *state,
+				      struct v4l2_subdev_selection *sel)
+{
+	if (sel->pad || sel->target != V4L2_SEL_TGT_CROP)
+		return -EINVAL;
+
+	sel->r = *v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
+
+	return 0;
+}
+
+static int mali_c55_isp_set_selection(struct v4l2_subdev *sd,
+				      struct v4l2_subdev_state *state,
+				      struct v4l2_subdev_selection *sel)
+{
+	struct v4l2_mbus_framefmt *src_fmt;
+	struct v4l2_mbus_framefmt *fmt;
+	struct v4l2_rect *crop;
+
+	if (sel->pad || sel->target != V4L2_SEL_TGT_CROP)
+		return -EINVAL;
+
+	fmt = v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SINK_VIDEO);
+
+	clamp_t(unsigned int, sel->r.left, 0, fmt->width);
+	clamp_t(unsigned int, sel->r.top, 0, fmt->height);
+	clamp_t(unsigned int, sel->r.width, MALI_C55_MIN_WIDTH,
+		fmt->width - sel->r.left);
+	clamp_t(unsigned int, sel->r.height, MALI_C55_MIN_HEIGHT,
+		fmt->height - sel->r.top);
+
+	crop = v4l2_subdev_state_get_crop(state, MALI_C55_ISP_PAD_SINK_VIDEO);
+	*crop = sel->r;
+
+	/* Propagate the crop rectangle sizes to the source pad format. */
+	src_fmt = v4l2_subdev_state_get_format(state, MALI_C55_ISP_PAD_SOURCE);
+	src_fmt->width = crop->width;
+	src_fmt->height = crop->height;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_pad_ops mali_c55_isp_pad_ops = {
+	.enum_mbus_code		= mali_c55_isp_enum_mbus_code,
+	.enum_frame_size	= mali_c55_isp_enum_frame_size,
+	.get_fmt		= v4l2_subdev_get_fmt,
+	.set_fmt		= mali_c55_isp_set_fmt,
+	.get_selection		= mali_c55_isp_get_selection,
+	.set_selection		= mali_c55_isp_set_selection,
+	.link_validate		= v4l2_subdev_link_validate_default,
+};
+
+void mali_c55_isp_queue_event_sof(struct mali_c55 *mali_c55)
+{
+	struct v4l2_event event = {
+		.type = V4L2_EVENT_FRAME_SYNC,
+	};
+
+	event.u.frame_sync.frame_sequence = mali_c55->isp.frame_sequence;
+	v4l2_event_queue(mali_c55->isp.sd.devnode, &event);
+}
+
+static int
+mali_c55_isp_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
+			     struct v4l2_event_subscription *sub)
+{
+	if (sub->type != V4L2_EVENT_FRAME_SYNC)
+		return -EINVAL;
+
+	/* V4L2_EVENT_FRAME_SYNC doesn't require an id, so zero should be set */
+	if (sub->id != 0)
+		return -EINVAL;
+
+	return v4l2_event_subscribe(fh, sub, 0, NULL);
+}
+
+static const struct v4l2_subdev_core_ops mali_c55_isp_core_ops = {
+	.subscribe_event = mali_c55_isp_subscribe_event,
+	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
+};
+
+static const struct v4l2_subdev_ops mali_c55_isp_ops = {
+	.pad	= &mali_c55_isp_pad_ops,
+	.core	= &mali_c55_isp_core_ops,
+};
+
+static int mali_c55_isp_init_state(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_state *sd_state)
+{
+	struct v4l2_mbus_framefmt *sink_fmt, *src_fmt;
+	struct v4l2_rect *in_crop;
+
+	sink_fmt = v4l2_subdev_state_get_format(sd_state,
+						MALI_C55_ISP_PAD_SINK_VIDEO);
+	src_fmt = v4l2_subdev_state_get_format(sd_state,
+					       MALI_C55_ISP_PAD_SOURCE);
+	in_crop = v4l2_subdev_state_get_crop(sd_state,
+					     MALI_C55_ISP_PAD_SINK_VIDEO);
+
+	sink_fmt->width = MALI_C55_DEFAULT_WIDTH;
+	sink_fmt->height = MALI_C55_DEFAULT_HEIGHT;
+	sink_fmt->field = V4L2_FIELD_NONE;
+	sink_fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
+
+	*v4l2_subdev_state_get_format(sd_state,
+			      MALI_C55_ISP_PAD_SOURCE_BYPASS) = *sink_fmt;
+
+	src_fmt->width = MALI_C55_DEFAULT_WIDTH;
+	src_fmt->height = MALI_C55_DEFAULT_HEIGHT;
+	src_fmt->field = V4L2_FIELD_NONE;
+	src_fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
+
+	in_crop->top = 0;
+	in_crop->left = 0;
+	in_crop->width = MALI_C55_DEFAULT_WIDTH;
+	in_crop->height = MALI_C55_DEFAULT_HEIGHT;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_internal_ops mali_c55_isp_internal_ops = {
+	.init_state = mali_c55_isp_init_state,
+};
+
+static const struct media_entity_operations mali_c55_isp_media_ops = {
+	.link_validate		= v4l2_subdev_link_validate,
+};
+
+static int mali_c55_isp_notifier_bound(struct v4l2_async_notifier *notifier,
+				       struct v4l2_subdev *subdev,
+				       struct v4l2_async_connection *asc)
+{
+	struct mali_c55_isp *isp = container_of(notifier,
+						struct mali_c55_isp, notifier);
+	struct mali_c55 *mali_c55 = isp->mali_c55;
+	struct media_pad *pad = &isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO];
+	int ret;
+
+	/*
+	 * By default we'll flag this link enabled and the TPG disabled, but
+	 * no immutable flag because we need to be able to switch between the
+	 * two.
+	 */
+	ret = v4l2_create_fwnode_links_to_pad(subdev, pad,
+					      MEDIA_LNK_FL_ENABLED);
+	if (ret)
+		dev_err(mali_c55->dev, "failed to create link for %s\n",
+			subdev->name);
+
+	return ret;
+}
+
+static int mali_c55_isp_notifier_complete(struct v4l2_async_notifier *notifier)
+{
+	struct mali_c55_isp *isp = container_of(notifier,
+						struct mali_c55_isp, notifier);
+	struct mali_c55 *mali_c55 = isp->mali_c55;
+
+	return v4l2_device_register_subdev_nodes(&mali_c55->v4l2_dev);
+}
+
+static const struct v4l2_async_notifier_operations mali_c55_isp_notifier_ops = {
+	.bound = mali_c55_isp_notifier_bound,
+	.complete = mali_c55_isp_notifier_complete,
+};
+
+static int mali_c55_isp_parse_endpoint(struct mali_c55_isp *isp)
+{
+	struct mali_c55 *mali_c55 = isp->mali_c55;
+	struct v4l2_async_connection *asc;
+	struct fwnode_handle *ep;
+	int ret;
+
+	v4l2_async_nf_init(&isp->notifier, &mali_c55->v4l2_dev);
+
+	/*
+	 * The ISP should have a single endpoint pointing to some flavour of
+	 * CSI-2 receiver...but for now at least we do want everything to work
+	 * normally even with no sensors connected, as we have the TPG. If we
+	 * don't find a sensor just warn and return success.
+	 */
+	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(mali_c55->dev),
+					     0, 0, 0);
+	if (!ep) {
+		dev_warn(mali_c55->dev, "no local endpoint found\n");
+		return 0;
+	}
+
+	asc = v4l2_async_nf_add_fwnode_remote(&isp->notifier, ep,
+					      struct v4l2_async_connection);
+	if (IS_ERR(asc)) {
+		dev_err(mali_c55->dev, "failed to add remote fwnode\n");
+		ret = PTR_ERR(asc);
+		goto err_put_ep;
+	}
+
+	isp->notifier.ops = &mali_c55_isp_notifier_ops;
+	ret = v4l2_async_nf_register(&isp->notifier);
+	if (ret) {
+		dev_err(mali_c55->dev, "failed to register notifier\n");
+		goto err_cleanup_nf;
+	}
+
+	fwnode_handle_put(ep);
+
+	return 0;
+
+err_cleanup_nf:
+	v4l2_async_nf_cleanup(&isp->notifier);
+err_put_ep:
+	fwnode_handle_put(ep);
+
+	return ret;
+}
+
+int mali_c55_register_isp(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_isp *isp = &mali_c55->isp;
+	struct v4l2_subdev *sd = &isp->sd;
+	int ret;
+
+	isp->mali_c55 = mali_c55;
+
+	v4l2_subdev_init(sd, &mali_c55_isp_ops);
+	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
+	sd->entity.ops = &mali_c55_isp_media_ops;
+	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_ISP;
+	sd->owner = THIS_MODULE;
+	sd->internal_ops = &mali_c55_isp_internal_ops;
+	strscpy(sd->name, MALI_C55_DRIVER_NAME " isp", sizeof(sd->name));
+
+	isp->pads[MALI_C55_ISP_PAD_SINK_VIDEO].flags = MEDIA_PAD_FL_SINK;
+	isp->pads[MALI_C55_ISP_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
+	isp->pads[MALI_C55_ISP_PAD_SOURCE_BYPASS].flags = MEDIA_PAD_FL_SOURCE;
+
+	ret = media_entity_pads_init(&sd->entity, MALI_C55_ISP_NUM_PADS,
+				     isp->pads);
+	if (ret)
+		return ret;
+
+	ret = v4l2_subdev_init_finalize(sd);
+	if (ret)
+		goto err_cleanup_media_entity;
+
+	ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
+	if (ret)
+		goto err_cleanup_subdev;
+
+	ret = mali_c55_isp_parse_endpoint(isp);
+	if (ret)
+		goto err_cleanup_subdev;
+
+	mutex_init(&isp->lock);
+
+	return 0;
+
+err_cleanup_subdev:
+	v4l2_subdev_cleanup(sd);
+err_cleanup_media_entity:
+	media_entity_cleanup(&sd->entity);
+	isp->mali_c55 = NULL;
+
+	return ret;
+}
+
+void mali_c55_unregister_isp(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_isp *isp = &mali_c55->isp;
+
+	if (!isp->mali_c55)
+		return;
+
+	mutex_destroy(&isp->lock);
+	v4l2_async_nf_unregister(&isp->notifier);
+	v4l2_device_unregister_subdev(&isp->sd);
+	v4l2_subdev_cleanup(&isp->sd);
+	media_entity_cleanup(&isp->sd.entity);
+}
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-registers.h b/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
new file mode 100644
index 000000000000..9636f08544fa
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
@@ -0,0 +1,180 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM Mali-C55 ISP Driver - Register definitions
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#ifndef _MALI_C55_REGISTERS_H
+#define _MALI_C55_REGISTERS_H
+
+#include <linux/bits.h>
+
+/* ISP Common 0x00000 - 0x000ff */
+
+#define MALI_C55_REG_API				0x00000
+#define MALI_C55_REG_PRODUCT				0x00004
+#define MALI_C55_REG_VERSION				0x00008
+#define MALI_C55_REG_REVISION				0x0000c
+#define MALI_C55_REG_PULSE_MODE				0x0003c
+#define MALI_C55_REG_INPUT_MODE_REQUEST			0x0009c
+#define MALI_C55_INPUT_SAFE_STOP			0x00
+#define MALI_C55_INPUT_SAFE_START			0x01
+#define MALI_C55_REG_MODE_STATUS			0x000a0
+#define MALI_C55_REG_INTERRUPT_MASK_VECTOR		0x00030
+#define MALI_C55_INTERRUPT_MASK_ALL			GENMASK(31, 0)
+
+#define MALI_C55_REG_GLOBAL_MONITOR			0x00050
+
+#define MALI_C55_REG_GEN_VIDEO				0x00080
+#define MALI_C55_REG_GEN_VIDEO_ON_MASK			BIT(0)
+#define MALI_C55_REG_GEN_VIDEO_MULTI_MASK		BIT(1)
+#define MALI_C55_REG_GEN_PREFETCH_MASK			GENMASK(31, 16)
+
+#define MALI_C55_REG_MCU_CONFIG				0x00020
+#define MALI_C55_REG_MCU_CONFIG_OVERRIDE_MASK		BIT(0)
+#define MALI_C55_REG_MCU_CONFIG_WRITE_MASK		BIT(1)
+#define MALI_C55_REG_MCU_CONFIG_WRITE_PING		BIT(1)
+#define MALI_C55_REG_MCU_CONFIG_WRITE_PONG		0x00
+#define MALI_C55_REG_MULTI_CONTEXT_MODE_MASK		BIT(8)
+#define MALI_C55_REG_PING_PONG_READ			0x00024
+#define MALI_C55_REG_PING_PONG_READ_MASK		BIT(2)
+
+#define MALI_C55_REG_INTERRUPT_CLEAR_VECTOR		0x00034
+#define MALI_C55_REG_INTERRUPT_CLEAR			0x00040
+#define MALI_C55_REG_INTERRUPT_STATUS_VECTOR		0x00044
+#define MALI_C55_REG_GLOBAL_PARAMETER_STATUS		0x00068
+#define MALI_C55_GPS_PONG_FITTED			BIT(0)
+#define MALI_C55_GPS_WDR_FITTED				BIT(1)
+#define MALI_C55_GPS_COMPRESSION_FITTED			BIT(2)
+#define MALI_C55_GPS_TEMPER_FITTED			BIT(3)
+#define MALI_C55_GPS_SINTER_LITE_FITTED			BIT(4)
+#define MALI_C55_GPS_SINTER_FITTED			BIT(5)
+#define MALI_C55_GPS_IRIDIX_LTM_FITTED			BIT(6)
+#define MALI_C55_GPS_IRIDIX_GTM_FITTED			BIT(7)
+#define MALI_C55_GPS_CNR_FITTED				BIT(8)
+#define MALI_C55_GPS_FRSCALER_FITTED			BIT(9)
+#define MALI_C55_GPS_DS_PIPE_FITTED			BIT(10)
+
+#define MALI_C55_REG_BLANKING				0x00084
+#define MALI_C55_REG_HBLANK_MASK			GENMASK(15, 0)
+#define MALI_C55_REG_VBLANK_MASK			GENMASK(31, 16)
+
+#define MALI_C55_REG_HC_START				0x00088
+#define MALI_C55_HC_START(h)				(((h) & 0xffff) << 16)
+#define MALI_C55_REG_HC_SIZE				0x0008c
+#define MALI_C55_HC_SIZE(h)				((h) & 0xffff)
+#define MALI_C55_REG_VC_START_SIZE			0x00094
+#define MALI_C55_VC_START(v)				((v) & 0xffff)
+#define MALI_C55_VC_SIZE(v)				(((v) & 0xffff) << 16)
+
+/* Ping/Pong Configuration Space */
+#define MALI_C55_REG_BASE_ADDR				0x18e88
+#define MALI_C55_REG_FR_BYPASS				0x18ec4
+#define MALI_C55_REG_DS_BYPASS				0x18ec8
+#define MALI_C55_BYPASS_CROP				BIT(0)
+#define MALI_C55_BYPASS_SCALER				BIT(1)
+#define MALI_C55_BYPASS_GAMMA_RGB			BIT(2)
+#define MALI_C55_BYPASS_SHARPEN				BIT(3)
+#define MALI_C55_BYPASS_CS_CONV				BIT(4)
+#define MALI_C55_REG_ISP_RAW_BYPASS			0x18ecc
+#define MALI_C55_ISP_RAW_BYPASS_BYPASS_MASK		BIT(0)
+#define MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK		GENMASK(9, 8)
+#define MALI_C55_ISP_RAW_BYPASS_RAW_FR_BYPASS		2
+#define MALI_C55_ISP_RAW_BYPASS_RGB_FR_BYPASS		1
+#define MALI_C55_ISP_RAW_BYPASS_DS_PIPE_DISABLE		BIT(1)
+#define MALI_C55_ISP_RAW_BYPASS_RAW_BYPASS		BIT(0)
+
+#define MALI_C55_REG_ACTIVE_WIDTH_MASK			0xffff
+#define MALI_C55_REG_ACTIVE_HEIGHT_MASK			0xffff0000
+#define MALI_C55_REG_BAYER_ORDER			0x18e8c
+#define MALI_C55_BAYER_ORDER_MASK			GENMASK(1, 0)
+#define MALI_C55_REG_TPG_CH0				0x18ed8
+#define MALI_C55_TEST_PATTERN_ON_OFF			BIT(0)
+#define MALI_C55_TEST_PATTERN_RGB_MASK			BIT(1)
+#define MALI_C55_REG_TPG_R_BACKGROUND			0x18ee0
+#define MALI_C55_REG_TPG_G_BACKGROUND			0x18ee4
+#define MALI_C55_REG_TPG_B_BACKGROUND			0x18ee8
+#define MALI_C55_TPG_BACKGROUND_MAX			0xfffff
+#define MALI_C55_REG_INPUT_WIDTH			0x18f98
+#define MALI_C55_INPUT_WIDTH_MASK			GENMASK(18, 16)
+#define MALI_C55_INPUT_WIDTH_8BIT			0
+#define MALI_C55_INPUT_WIDTH_10BIT			1
+#define MALI_C55_INPUT_WIDTH_12BIT			2
+#define MALI_C55_INPUT_WIDTH_14BIT			3
+#define MALI_C55_INPUT_WIDTH_16BIT			4
+#define MALI_C55_INPUT_WIDTH_20BIT			5
+#define MALI_C55_REG_SPACE_SIZE				0x4000
+#define MALI_C55_REG_CONFIG_SPACES_OFFSET		0x0ab6c
+#define MALI_C55_CONFIG_SPACE_SIZE			0x1231c
+
+#define MALI_C55_REG_CS_CONV_CONFIG(offset)		(0x1c098 + (offset))
+#define MALI_C55_CS_CONV_MATRIX_MASK			BIT(0)
+#define MALI_C55_CS_CONV_FILTER_MASK			BIT(1)
+#define MALI_C55_CS_CONV_HORZ_DOWNSAMPLE_MASK		BIT(2)
+#define MALI_C55_CS_CONV_VERT_DOWNSAMPLE_MASK		BIT(3)
+#define MALI_C55_REG_Y_WRITER_MODE(offset)		(0x1c0ec + (offset))
+#define MALI_C55_REG_UV_WRITER_MODE(offset)		(0x1c144 + (offset))
+#define MALI_C55_WRITER_MODE_MASK			GENMASK(4, 0)
+#define MALI_C55_WRITER_SUBMODE_MASK			GENMASK(7, 6)
+#define MALI_C55_WRITER_FRAME_WRITE_MASK		BIT(9)
+#define MALI_C55_REG_ACTIVE_OUT_Y_SIZE(offset)		(0x1c0f0 + (offset))
+#define MALI_C55_REG_ACTIVE_OUT_UV_SIZE(offset)		(0x1c148 + (offset))
+#define MALI_C55_REG_ACTIVE_OUT_SIZE_W(w)		((w) << 0)
+#define MALI_C55_REG_ACTIVE_OUT_SIZE_H(h)		((h) << 16)
+#define MALI_C55_REG_Y_WRITER_BANKS_BASE(offset)	(0x1c0f4 + (offset))
+#define MALI_C55_REG_Y_WRITER_BANKS_CONFIG(offset)	(0x1c108 + (offset))
+#define MALI_C55_REG_Y_WRITER_MAX_BANKS_MASK		GENMASK(2, 0)
+#define MALI_C55_REG_Y_WRITER_BANKS_RESTART		BIT(3)
+#define MALI_C55_REG_Y_WRITER_OFFSET(offset)		(0x1c10c + (offset))
+#define MALI_C55_REG_UV_WRITER_BANKS_BASE(offset)	(0x1c14c + (offset))
+#define MALI_C55_REG_UV_WRITER_BANKS_CONFIG(offset)	(0x1c160 + (offset))
+#define MALI_C55_REG_UV_WRITER_MAX_BANKS_MASK		GENMASK(2, 0)
+#define MALI_C55_REG_UV_WRITER_BANKS_RESTART		BIT(3)
+#define MALI_C55_REG_UV_WRITER_OFFSET(offset)		(0x1c164 + (offset))
+
+#define MALI_C55_REG_TEST_GEN_CH0_OFF_ON
+#define MALI_C55_REG_TEST_GEN_CH0_PATTERN_TYPE		0x18edc
+
+#define MALI_C55_REG_CROP_EN(offset)			(0x1c028 + (offset))
+#define MALI_C55_CROP_ENABLE				BIT(0)
+#define MALI_C55_REG_CROP_X_START(offset)		(0x1c02c + (offset))
+#define MALI_C55_REG_CROP_Y_START(offset)		(0x1c030 + (offset))
+#define MALI_C55_REG_CROP_X_SIZE(offset)		(0x1c034 + (offset))
+#define MALI_C55_REG_CROP_Y_SIZE(offset)		(0x1c038 + (offset))
+#define MALI_C55_REG_SCALER_TIMEOUT_EN(offset)		(0x1c040 + (offset))
+#define MALI_C55_SCALER_TIMEOUT_EN			BIT(4)
+#define MALI_C55_SCALER_TIMEOUT(t)			((t) << 16)
+#define MALI_C55_REG_SCALER_IN_WIDTH(offset)		(0x1c044 + (offset))
+#define MALI_C55_REG_SCALER_IN_HEIGHT(offset)		(0x1c048 + (offset))
+#define MALI_C55_REG_SCALER_OUT_WIDTH(offset)		(0x1c04c + (offset))
+#define MALI_C55_REG_SCALER_OUT_HEIGHT(offset)		(0x1c050 + (offset))
+#define MALI_C55_REG_SCALER_HFILT_TINC(offset)		(0x1c054 + (offset))
+#define MALI_C55_REG_SCALER_HFILT_COEF(offset)		(0x1c058 + (offset))
+#define MALI_C55_REG_SCALER_VFILT_TINC(offset)		(0x1c05c + (offset))
+#define MALI_C55_REG_SCALER_VFILT_COEF(offset)		(0x1c060 + (offset))
+
+/* Output DMA Writer */
+
+#define MALI_C55_OUTPUT_DISABLED		0
+#define MALI_C55_OUTPUT_RGB32			1
+#define MALI_C55_OUTPUT_A2R10G10B10		2
+#define MALI_C55_OUTPUT_RGB565			3
+#define MALI_C55_OUTPUT_RGB24			4
+#define MALI_C55_OUTPUT_GEN32			5
+#define MALI_C55_OUTPUT_RAW16			6
+#define MALI_C55_OUTPUT_AYUV			8
+#define MALI_C55_OUTPUT_Y410			9
+#define MALI_C55_OUTPUT_YUY2			10
+#define MALI_C55_OUTPUT_UYVY			11
+#define MALI_C55_OUTPUT_Y210			12
+#define MALI_C55_OUTPUT_NV12_21			13
+#define MALI_C55_OUTPUT_YUV_420_422		17
+#define MALI_C55_OUTPUT_P210_P010		19
+#define MALI_C55_OUTPUT_YUV422			20
+
+#define MALI_C55_OUTPUT_PLANE_ALT0		0
+#define MALI_C55_OUTPUT_PLANE_ALT1		1
+#define MALI_C55_OUTPUT_PLANE_ALT2		2
+
+#endif /* _MALI_C55_REGISTERS_H */
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h b/drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h
new file mode 100644
index 000000000000..eea473c36922
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-resizer-coefs.h
@@ -0,0 +1,382 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM Mali-C55 ISP Driver - Resizer Coefficients
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#ifndef _MALI_C55_RESIZER_COEFS_H
+#define _MALI_C55_RESIZER_COEFS_H
+
+#include "mali-c55-common.h"
+
+#define MALI_C55_RESIZER_COEFS_NUM_BANKS	8
+#define MALI_C55_RESIZER_COEFS_NUM_ENTRIES	64
+
+static const unsigned int mali_c55_scaler_h_filter_coefficients[8][64] = {
+	{	/* Bank 0 */
+		0x24fc0000, 0x0000fc24, 0x27fc0000, 0x0000fc21,
+		0x28fc0000, 0x0000fd1f, 0x2cfb0000, 0x0000fd1c,
+		0x2efb0000, 0x0000fd1a, 0x30fb0000, 0x0000fe17,
+		0x32fb0000, 0x0000fe15, 0x35fb0000, 0x0000fe12,
+		0x35fc0000, 0x0000ff10, 0x37fc0000, 0x0000ff0e,
+		0x39fc0000, 0x0000ff0c, 0x3afd0000, 0x0000ff0a,
+		0x3afe0000, 0x00000008, 0x3cfe0000, 0x00000006,
+		0x3dff0000, 0x00000004, 0x3d000000, 0x00000003,
+		0x3c020000, 0x00000002, 0x3d030000, 0x00000000,
+		0x3d040000, 0x000000ff, 0x3c060000, 0x000000fe,
+		0x3a080000, 0x000000fe, 0x3a0aff00, 0x000000fd,
+		0x390cff00, 0x000000fc, 0x370eff00, 0x000000fc,
+		0x3510ff00, 0x000000fc, 0x3512fe00, 0x000000fb,
+		0x3215fe00, 0x000000fb, 0x3017fe00, 0x000000fb,
+		0x2e1afd00, 0x000000fb, 0x2c1cfd00, 0x000000fb,
+		0x281ffd00, 0x000000fc, 0x2721fc00, 0x000000fc,
+	},
+	{	/* Bank 1 */
+		0x25fb0000, 0x0000fb25, 0x27fb0000, 0x0000fb23,
+		0x29fb0000, 0x0000fb21, 0x2afc0000, 0x0000fb1f,
+		0x2cfc0000, 0x0000fb1d, 0x2efc0000, 0x0000fb1b,
+		0x2ffd0000, 0x0000fb19, 0x2ffe0000, 0x0000fc17,
+		0x31fe0000, 0x0000fc15, 0x32ff0000, 0x0000fc13,
+		0x3400ff00, 0x0000fc11, 0x3301ff00, 0x0000fd10,
+		0x3402ff00, 0x0000fd0e, 0x3503ff00, 0x0000fd0c,
+		0x3505ff00, 0x0000fd0a, 0x3506fe00, 0x0000fe09,
+		0x3607fe00, 0x0000fe07, 0x3509fe00, 0x0000fe06,
+		0x350afd00, 0x0000ff05, 0x350cfd00, 0x0000ff03,
+		0x340efd00, 0x0000ff02, 0x3310fd00, 0x0000ff01,
+		0x3411fc00, 0x0000ff00, 0x3213fc00, 0x000000ff,
+		0x3115fc00, 0x000000fe, 0x2f17fc00, 0x000000fe,
+		0x2f19fb00, 0x000000fd, 0x2e1bfb00, 0x000000fc,
+		0x2c1dfb00, 0x000000fc, 0x2a1ffb00, 0x000000fc,
+		0x2921fb00, 0x000000fb, 0x2723fb00, 0x000000fb,
+	},
+	{	/* Bank 2 */
+		0x1f010000, 0x0000011f, 0x21010000, 0x0000001e,
+		0x21020000, 0x0000001d, 0x22020000, 0x0000001c,
+		0x23030000, 0x0000ff1b, 0x2404ff00, 0x0000ff1a,
+		0x2504ff00, 0x0000ff19, 0x2505ff00, 0x0000ff18,
+		0x2606ff00, 0x0000fe17, 0x2607ff00, 0x0000fe16,
+		0x2708ff00, 0x0000fe14, 0x2709ff00, 0x0000fe13,
+		0x270aff00, 0x0000fe12, 0x280bfe00, 0x0000fe11,
+		0x280cfe00, 0x0000fe10, 0x280dfe00, 0x0000fe0f,
+		0x280efe00, 0x0000fe0e, 0x280ffe00, 0x0000fe0d,
+		0x2810fe00, 0x0000fe0c, 0x2811fe00, 0x0000fe0b,
+		0x2712fe00, 0x0000ff0a, 0x2713fe00, 0x0000ff09,
+		0x2714fe00, 0x0000ff08, 0x2616fe00, 0x0000ff07,
+		0x2617fe00, 0x0000ff06, 0x2518ff00, 0x0000ff05,
+		0x2519ff00, 0x0000ff04, 0x241aff00, 0x0000ff04,
+		0x231bff00, 0x00000003, 0x221c0000, 0x00000002,
+		0x211d0000, 0x00000002, 0x211e0000, 0x00000001,
+	},
+	{	/* Bank 3 */
+		0x1b06ff00, 0x00ff061b, 0x1b07ff00, 0x00ff061a,
+		0x1c07ff00, 0x00ff051a, 0x1c08ff00, 0x00ff0519,
+		0x1c09ff00, 0x00ff0419, 0x1d09ff00, 0x00ff0418,
+		0x1e0aff00, 0x00ff0317, 0x1e0aff00, 0x00ff0317,
+		0x1e0bff00, 0x00ff0316, 0x1f0cff00, 0x00ff0215,
+		0x1e0cff00, 0x00000215, 0x1e0dff00, 0x00000214,
+		0x1e0e0000, 0x00000113, 0x1e0e0000, 0x00000113,
+		0x1e0f0000, 0x00000112, 0x1f100000, 0x00000011,
+		0x20100000, 0x00000010, 0x1f110000, 0x00000010,
+		0x1e120100, 0x0000000f, 0x1e130100, 0x0000000e,
+		0x1e130100, 0x0000000e, 0x1e140200, 0x0000ff0d,
+		0x1e150200, 0x0000ff0c, 0x1f1502ff, 0x0000ff0c,
+		0x1e1603ff, 0x0000ff0b, 0x1e1703ff, 0x0000ff0a,
+		0x1e1703ff, 0x0000ff0a, 0x1d1804ff, 0x0000ff09,
+		0x1c1904ff, 0x0000ff09, 0x1c1905ff, 0x0000ff08,
+		0x1c1a05ff, 0x0000ff07, 0x1b1a06ff, 0x0000ff07,
+	},
+	{	/* Bank 4 */
+		0x17090000, 0x00000917, 0x18090000, 0x00000916,
+		0x170a0100, 0x00000816, 0x170a0100, 0x00000816,
+		0x180b0100, 0x00000715, 0x180b0100, 0x00000715,
+		0x170c0100, 0x00000715, 0x190c0100, 0x00000614,
+		0x180d0100, 0x00000614, 0x190d0200, 0x00000513,
+		0x180e0200, 0x00000513, 0x180e0200, 0x00000513,
+		0x1a0e0200, 0x00000412, 0x190f0200, 0x00000412,
+		0x190f0300, 0x00000411, 0x18100300, 0x00000411,
+		0x1a100300, 0x00000310, 0x18110400, 0x00000310,
+		0x19110400, 0x0000030f, 0x19120400, 0x0000020f,
+		0x1a120400, 0x0000020e, 0x18130500, 0x0000020e,
+		0x18130500, 0x0000020e, 0x19130500, 0x0000020d,
+		0x18140600, 0x0000010d, 0x19140600, 0x0000010c,
+		0x17150700, 0x0000010c, 0x18150700, 0x0000010b,
+		0x18150700, 0x0000010b, 0x17160800, 0x0000010a,
+		0x17160800, 0x0000010a, 0x18160900, 0x00000009,
+	},
+	{	/* Bank 5 */
+		0x120b0300, 0x00030b12, 0x120c0300, 0x00030b11,
+		0x110c0400, 0x00030b11, 0x110c0400, 0x00030b11,
+		0x130c0400, 0x00020a11, 0x120d0400, 0x00020a11,
+		0x110d0500, 0x00020a11, 0x110d0500, 0x00020a11,
+		0x130d0500, 0x00010911, 0x130e0500, 0x00010910,
+		0x120e0600, 0x00010910, 0x120e0600, 0x00010910,
+		0x130e0600, 0x00010810, 0x120f0600, 0x00010810,
+		0x120f0700, 0x00000810, 0x130f0700, 0x0000080f,
+		0x140f0700, 0x0000070f, 0x130f0800, 0x0000070f,
+		0x12100800, 0x0000070f, 0x12100801, 0x0000060f,
+		0x13100801, 0x0000060e, 0x12100901, 0x0000060e,
+		0x12100901, 0x0000060e, 0x13100901, 0x0000050e,
+		0x13110901, 0x0000050d, 0x11110a02, 0x0000050d,
+		0x11110a02, 0x0000050d, 0x12110a02, 0x0000040d,
+		0x13110a02, 0x0000040c, 0x11110b03, 0x0000040c,
+		0x11110b03, 0x0000040c, 0x12110b03, 0x0000030c,
+	},
+	{	/* Bank 6 */
+		0x0b0a0805, 0x00080a0c, 0x0b0a0805, 0x00080a0c,
+		0x0c0a0805, 0x00080a0b, 0x0c0a0805, 0x00080a0b,
+		0x0d0a0805, 0x00070a0b, 0x0d0a0805, 0x00070a0b,
+		0x0d0a0805, 0x00070a0b, 0x0c0a0806, 0x00070a0b,
+		0x0b0b0806, 0x00070a0b, 0x0c0b0806, 0x0007090b,
+		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
+		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
+		0x0b0b0906, 0x0007090b, 0x0c0b0906, 0x0006090b,
+		0x0c0b0906, 0x0006090b, 0x0c0b0906, 0x0006090b,
+		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
+		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
+		0x0b0b0907, 0x0006090b, 0x0c0b0907, 0x0006080b,
+		0x0b0b0a07, 0x0006080b, 0x0c0b0a07, 0x0006080a,
+		0x0d0b0a07, 0x0005080a, 0x0d0b0a07, 0x0005080a,
+		0x0d0b0a07, 0x0005080a, 0x0c0b0a08, 0x0005080a,
+		0x0c0b0a08, 0x0005080a, 0x0c0b0a08, 0x0005080a,
+	},
+	{	/* Bank 7 */
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+		0x0909090a, 0x00090909, 0x0909090a, 0x00090909,
+	}
+};
+
+static const unsigned int mali_c55_scaler_v_filter_coefficients[8][64] = {
+	{	/* Bank 0 */
+		0x2424fc00, 0x000000fc, 0x2721fc00, 0x000000fc,
+		0x281ffd00, 0x000000fc, 0x2c1cfd00, 0x000000fb,
+		0x2e1afd00, 0x000000fb, 0x3017fe00, 0x000000fb,
+		0x3215fe00, 0x000000fb, 0x3512fe00, 0x000000fb,
+		0x3510ff00, 0x000000fc, 0x370eff00, 0x000000fc,
+		0x390cff00, 0x000000fc, 0x3a0aff00, 0x000000fd,
+		0x3a080000, 0x000000fe, 0x3c060000, 0x000000fe,
+		0x3d040000, 0x000000ff, 0x3d030000, 0x00000000,
+		0x3c020000, 0x00000002, 0x3d000000, 0x00000003,
+		0x3dff0000, 0x00000004, 0x3cfe0000, 0x00000006,
+		0x3afe0000, 0x00000008, 0x3afd0000, 0x0000ff0a,
+		0x39fc0000, 0x0000ff0c, 0x37fc0000, 0x0000ff0e,
+		0x35fc0000, 0x0000ff10, 0x35fb0000, 0x0000fe12,
+		0x32fb0000, 0x0000fe15, 0x30fb0000, 0x0000fe17,
+		0x2efb0000, 0x0000fd1a, 0x2cfb0000, 0x0000fd1c,
+		0x28fc0000, 0x0000fd1f, 0x27fc0000, 0x0000fc21,
+	},
+	{	/* Bank 1 */
+		0x2525fb00, 0x000000fb, 0x2723fb00, 0x000000fb,
+		0x2921fb00, 0x000000fb, 0x2a1ffb00, 0x000000fc,
+		0x2c1dfb00, 0x000000fc, 0x2e1bfb00, 0x000000fc,
+		0x2f19fb00, 0x000000fd, 0x2f17fc00, 0x000000fe,
+		0x3115fc00, 0x000000fe, 0x3213fc00, 0x000000ff,
+		0x3411fc00, 0x0000ff00, 0x3310fd00, 0x0000ff01,
+		0x340efd00, 0x0000ff02, 0x350cfd00, 0x0000ff03,
+		0x350afd00, 0x0000ff05, 0x3509fe00, 0x0000fe06,
+		0x3607fe00, 0x0000fe07, 0x3506fe00, 0x0000fe09,
+		0x3505ff00, 0x0000fd0a, 0x3503ff00, 0x0000fd0c,
+		0x3402ff00, 0x0000fd0e, 0x3301ff00, 0x0000fd10,
+		0x3400ff00, 0x0000fc11, 0x32ff0000, 0x0000fc13,
+		0x31fe0000, 0x0000fc15, 0x2ffe0000, 0x0000fc17,
+		0x2ffd0000, 0x0000fb19, 0x2efc0000, 0x0000fb1b,
+		0x2cfc0000, 0x0000fb1d, 0x2afc0000, 0x0000fb1f,
+		0x29fb0000, 0x0000fb21, 0x27fb0000, 0x0000fb23,
+	},
+	{	/* Bank 2 */
+		0x1f1f0100, 0x00000001, 0x211e0000, 0x00000001,
+		0x211d0000, 0x00000002, 0x221c0000, 0x00000002,
+		0x231bff00, 0x00000003, 0x241aff00, 0x0000ff04,
+		0x2519ff00, 0x0000ff04, 0x2518ff00, 0x0000ff05,
+		0x2617fe00, 0x0000ff06, 0x2616fe00, 0x0000ff07,
+		0x2714fe00, 0x0000ff08, 0x2713fe00, 0x0000ff09,
+		0x2712fe00, 0x0000ff0a, 0x2811fe00, 0x0000fe0b,
+		0x2810fe00, 0x0000fe0c, 0x280ffe00, 0x0000fe0d,
+		0x280efe00, 0x0000fe0e, 0x280dfe00, 0x0000fe0f,
+		0x280cfe00, 0x0000fe10, 0x280bfe00, 0x0000fe11,
+		0x270aff00, 0x0000fe12, 0x2709ff00, 0x0000fe13,
+		0x2708ff00, 0x0000fe14, 0x2607ff00, 0x0000fe16,
+		0x2606ff00, 0x0000fe17, 0x2505ff00, 0x0000ff18,
+		0x2504ff00, 0x0000ff19, 0x2404ff00, 0x0000ff1a,
+		0x23030000, 0x0000ff1b, 0x22020000, 0x0000001c,
+		0x21020000, 0x0000001d, 0x21010000, 0x0000001e,
+	},
+	{	/* Bank 3 */
+		0x1b1b06ff, 0x0000ff06, 0x1b1a06ff, 0x0000ff07,
+		0x1c1a05ff, 0x0000ff07, 0x1c1905ff, 0x0000ff08,
+		0x1c1904ff, 0x0000ff09, 0x1d1804ff, 0x0000ff09,
+		0x1e1703ff, 0x0000ff0a, 0x1e1703ff, 0x0000ff0a,
+		0x1e1603ff, 0x0000ff0b, 0x1f1502ff, 0x0000ff0c,
+		0x1e150200, 0x0000ff0c, 0x1e140200, 0x0000ff0d,
+		0x1e130100, 0x0000000e, 0x1e130100, 0x0000000e,
+		0x1e120100, 0x0000000f, 0x1f110000, 0x00000010,
+		0x20100000, 0x00000010, 0x1f100000, 0x00000011,
+		0x1e0f0000, 0x00000112, 0x1e0e0000, 0x00000113,
+		0x1e0e0000, 0x00000113, 0x1e0dff00, 0x00000214,
+		0x1e0cff00, 0x00000215, 0x1f0cff00, 0x00ff0215,
+		0x1e0bff00, 0x00ff0316, 0x1e0aff00, 0x00ff0317,
+		0x1e0aff00, 0x00ff0317, 0x1d09ff00, 0x00ff0418,
+		0x1c09ff00, 0x00ff0419, 0x1c08ff00, 0x00ff0519,
+		0x1c07ff00, 0x00ff051a, 0x1b07ff00, 0x00ff061a,
+	},
+	{	/* Bank 4 */
+		0x17170900, 0x00000009, 0x18160900, 0x00000009,
+		0x17160800, 0x0000010a, 0x17160800, 0x0000010a,
+		0x18150700, 0x0000010b, 0x18150700, 0x0000010b,
+		0x17150700, 0x0000010c, 0x19140600, 0x0000010c,
+		0x18140600, 0x0000010d, 0x19130500, 0x0000020d,
+		0x18130500, 0x0000020e, 0x18130500, 0x0000020e,
+		0x1a120400, 0x0000020e, 0x19120400, 0x0000020f,
+		0x19110400, 0x0000030f, 0x18110400, 0x00000310,
+		0x1a100300, 0x00000310, 0x18100300, 0x00000411,
+		0x190f0300, 0x00000411, 0x190f0200, 0x00000412,
+		0x1a0e0200, 0x00000412, 0x180e0200, 0x00000513,
+		0x180e0200, 0x00000513, 0x190d0200, 0x00000513,
+		0x180d0100, 0x00000614, 0x190c0100, 0x00000614,
+		0x170c0100, 0x00000715, 0x180b0100, 0x00000715,
+		0x180b0100, 0x00000715, 0x170a0100, 0x00000816,
+		0x170a0100, 0x00000816, 0x18090000, 0x00000916,
+	},
+	{	/* Bank 5 */
+		0x12120b03, 0x0000030b, 0x12110b03, 0x0000030c,
+		0x11110b03, 0x0000040c, 0x11110b03, 0x0000040c,
+		0x13110a02, 0x0000040c, 0x12110a02, 0x0000040d,
+		0x11110a02, 0x0000050d, 0x11110a02, 0x0000050d,
+		0x13110901, 0x0000050d, 0x13100901, 0x0000050e,
+		0x12100901, 0x0000060e, 0x12100901, 0x0000060e,
+		0x13100801, 0x0000060e, 0x12100801, 0x0000060f,
+		0x12100800, 0x0000070f, 0x130f0800, 0x0000070f,
+		0x140f0700, 0x0000070f, 0x130f0700, 0x0000080f,
+		0x120f0700, 0x00000810, 0x120f0600, 0x00010810,
+		0x130e0600, 0x00010810, 0x120e0600, 0x00010910,
+		0x120e0600, 0x00010910, 0x130e0500, 0x00010910,
+		0x130d0500, 0x00010911, 0x110d0500, 0x00020a11,
+		0x110d0500, 0x00020a11, 0x120d0400, 0x00020a11,
+		0x130c0400, 0x00020a11, 0x110c0400, 0x00030b11,
+		0x110c0400, 0x00030b11, 0x120c0300, 0x00030b11,
+	},
+	{	/* Bank 6 */
+		0x0b0c0a08, 0x0005080a, 0x0b0c0a08, 0x0005080a,
+		0x0c0b0a08, 0x0005080a, 0x0c0b0a08, 0x0005080a,
+		0x0d0b0a07, 0x0005080a, 0x0d0b0a07, 0x0005080a,
+		0x0d0b0a07, 0x0005080a, 0x0c0b0a07, 0x0006080a,
+		0x0b0b0a07, 0x0006080b, 0x0c0b0907, 0x0006080b,
+		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
+		0x0b0b0907, 0x0006090b, 0x0b0b0907, 0x0006090b,
+		0x0b0b0907, 0x0006090b, 0x0c0b0906, 0x0006090b,
+		0x0c0b0906, 0x0006090b, 0x0c0b0906, 0x0006090b,
+		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
+		0x0b0b0906, 0x0007090b, 0x0b0b0906, 0x0007090b,
+		0x0b0b0906, 0x0007090b, 0x0c0b0806, 0x0007090b,
+		0x0b0b0806, 0x00070a0b, 0x0c0a0806, 0x00070a0b,
+		0x0d0a0805, 0x00070a0b, 0x0d0a0805, 0x00070a0b,
+		0x0d0a0805, 0x00070a0b, 0x0c0a0805, 0x00080a0b,
+		0x0c0a0805, 0x00080a0b, 0x0c0a0805, 0x00080a0b,
+	},
+	{	/* Bank 7 */
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+		0x09090909, 0x000a0909, 0x09090909, 0x000a0909,
+	}
+};
+
+struct mali_c55_resizer_coef_bank {
+	unsigned int bank;
+	unsigned int top;
+	unsigned int bottom;
+};
+
+static const struct mali_c55_resizer_coef_bank mali_c55_coefficient_banks[] = {
+	{
+		.bank = 0,
+		.top = 1000,
+		.bottom = 770,
+	},
+	{
+		.bank = 1,
+		.top = 769,
+		.bottom = 600,
+	},
+	{
+		.bank = 2,
+		.top = 599,
+		.bottom = 460,
+	},
+	{
+		.bank = 3,
+		.top = 459,
+		.bottom = 354,
+	},
+	{
+		.bank = 4,
+		.top = 353,
+		.bottom = 273,
+	},
+	{
+		.bank = 5,
+		.top = 272,
+		.bottom = 210,
+	},
+	{
+		.bank = 6,
+		.top = 209,
+		.bottom = 162,
+	},
+	{
+		.bank = 7,
+		.top = 161,
+		.bottom = 125,
+	},
+};
+
+static unsigned int mali_c55_calculate_bank_num(struct mali_c55 *mali_c55,
+						unsigned int crop,
+						unsigned int scale)
+{
+	unsigned int tmp;
+	unsigned int i;
+
+	tmp = (scale * 1000) / crop;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55_coefficient_banks); i++) {
+		if (tmp >= mali_c55_coefficient_banks[i].bottom &&
+		    tmp <= mali_c55_coefficient_banks[i].top)
+			return mali_c55_coefficient_banks[i].bank;
+	}
+
+	/*
+	 * We shouldn't ever get here, in theory. As we have no good choices
+	 * simply warn the user and use the first bank of coefficients.
+	 */
+	dev_warn(mali_c55->dev, "scaling factor outside defined bounds\n");
+	return 0;
+}
+
+#endif /* _MALI_C55_RESIZER_COEFS_H */
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c b/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
new file mode 100644
index 000000000000..8e0669a5f391
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-resizer.c
@@ -0,0 +1,740 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Mali-C55 ISP Driver - Image signal processor
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#include <linux/math.h>
+#include <linux/minmax.h>
+
+#include <media/media-entity.h>
+#include <media/v4l2-subdev.h>
+
+#include "mali-c55-common.h"
+#include "mali-c55-registers.h"
+#include "mali-c55-resizer-coefs.h"
+
+/* Scaling factor in Q4.20 format. */
+#define MALI_C55_RZR_SCALER_FACTOR	1048576
+
+static const u32 rzr_non_bypass_src_fmts[] = {
+	MEDIA_BUS_FMT_RGB121212_1X36,
+	MEDIA_BUS_FMT_YUV10_1X30
+};
+
+static const char * const mali_c55_resizer_names[] = {
+	[MALI_C55_RZR_FR] = "resizer fr",
+	[MALI_C55_RZR_DS] = "resizer ds",
+};
+
+static int mali_c55_rzr_program_crop(struct mali_c55_resizer *rzr,
+				     struct v4l2_subdev_state *state)
+{
+	unsigned int reg_offset = rzr->cap_dev->reg_offset;
+	struct mali_c55 *mali_c55 = rzr->mali_c55;
+	struct v4l2_mbus_framefmt *fmt;
+	struct v4l2_rect *crop;
+
+	/* Verify if crop should be enabled. */
+	fmt = v4l2_subdev_state_get_format(state, MALI_C55_RZR_SINK_PAD, 0);
+	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD, 0);
+
+	if (fmt->width == crop->width && fmt->height == crop->height)
+		return MALI_C55_BYPASS_CROP;
+
+	mali_c55_write(mali_c55, MALI_C55_REG_CROP_X_START(reg_offset),
+		       crop->left);
+	mali_c55_write(mali_c55, MALI_C55_REG_CROP_Y_START(reg_offset),
+		       crop->top);
+	mali_c55_write(mali_c55, MALI_C55_REG_CROP_X_SIZE(reg_offset),
+		       crop->width);
+	mali_c55_write(mali_c55, MALI_C55_REG_CROP_Y_SIZE(reg_offset),
+		       crop->height);
+
+	mali_c55_write(mali_c55, MALI_C55_REG_CROP_EN(reg_offset),
+		       MALI_C55_CROP_ENABLE);
+
+	return 0;
+}
+
+static int mali_c55_rzr_program_resizer(struct mali_c55_resizer *rzr,
+					struct v4l2_subdev_state *state)
+{
+	unsigned int reg_offset = rzr->cap_dev->reg_offset;
+	struct mali_c55 *mali_c55 = rzr->mali_c55;
+	struct v4l2_rect *crop, *scale;
+	unsigned int h_bank, v_bank;
+	u64 h_scale, v_scale;
+
+	/* Verify if scaling should be enabled. */
+	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD, 0);
+	scale = v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD, 0);
+
+	if (crop->width == scale->width && crop->height == scale->height)
+		return MALI_C55_BYPASS_SCALER;
+
+	/* Program the V/H scaling factor in Q4.20 format. */
+	h_scale = crop->width * MALI_C55_RZR_SCALER_FACTOR;
+	v_scale = crop->height * MALI_C55_RZR_SCALER_FACTOR;
+
+	do_div(h_scale, scale->width);
+	do_div(v_scale, scale->height);
+
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_IN_WIDTH(reg_offset),
+		       crop->width);
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_IN_HEIGHT(reg_offset),
+		       crop->height);
+
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_OUT_WIDTH(reg_offset),
+		       scale->width);
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_OUT_HEIGHT(reg_offset),
+		       scale->height);
+
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_HFILT_TINC(reg_offset),
+		       h_scale);
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_VFILT_TINC(reg_offset),
+		       v_scale);
+
+	h_bank = mali_c55_calculate_bank_num(mali_c55, crop->width,
+					     scale->width);
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_HFILT_COEF(reg_offset),
+		       h_bank);
+
+	v_bank = mali_c55_calculate_bank_num(mali_c55, crop->height,
+					     scale->height);
+	mali_c55_write(mali_c55,
+		       MALI_C55_REG_SCALER_VFILT_COEF(reg_offset),
+		       v_bank);
+
+	return 0;
+}
+
+static void mali_c55_rzr_program(struct mali_c55_resizer *rzr,
+				 struct v4l2_subdev_state *state)
+{
+	struct mali_c55 *mali_c55 = rzr->mali_c55;
+	u32 bypass = 0;
+
+	/* Verify if cropping and scaling should be enabled. */
+	bypass |= mali_c55_rzr_program_crop(rzr, state);
+	bypass |= mali_c55_rzr_program_resizer(rzr, state);
+
+	mali_c55_update_bits(mali_c55, rzr->id == MALI_C55_RZR_FR ?
+			     MALI_C55_REG_FR_BYPASS : MALI_C55_REG_DS_BYPASS,
+			     MALI_C55_BYPASS_CROP | MALI_C55_BYPASS_SCALER,
+			     bypass);
+}
+
+/*
+ * Inspect the routing table to know which of the two (mutually exclusive)
+ * routes is enabled and return the sink pad id of the active route.
+ */
+static unsigned int mali_c55_rzr_get_active_sink(struct v4l2_subdev_state *state)
+{
+	struct v4l2_subdev_krouting *routing = &state->routing;
+	struct v4l2_subdev_route *route;
+
+	/* A single route is enabled at a time. */
+	for_each_active_route(routing, route)
+		return route->sink_pad;
+
+	return MALI_C55_RZR_SINK_PAD;
+}
+
+static int __mali_c55_rzr_set_routing(struct v4l2_subdev *sd,
+				      struct v4l2_subdev_state *state,
+				      struct v4l2_subdev_krouting *routing)
+{
+	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
+						    sd);
+	unsigned int active_sink = UINT_MAX;
+	struct v4l2_rect *crop, *compose;
+	struct v4l2_subdev_route *route;
+	unsigned int active_routes = 0;
+	struct v4l2_mbus_framefmt *fmt;
+	int ret;
+
+	ret = v4l2_subdev_routing_validate(sd, routing, 0);
+	if (ret)
+		return ret;
+
+	/* Only a single route can be enabled at a time. */
+	for_each_active_route(routing, route) {
+		if (++active_routes > 1) {
+			dev_err(rzr->mali_c55->dev,
+				"Only one route can be active");
+			return -EINVAL;
+		}
+
+		active_sink = route->sink_pad;
+	}
+	if (active_sink == UINT_MAX) {
+		dev_err(rzr->mali_c55->dev, "One route has to be active");
+		return -EINVAL;
+	}
+
+	ret = v4l2_subdev_set_routing(sd, state, routing);
+	if (ret) {
+		dev_err(rzr->mali_c55->dev, "Failed to set routing\n");
+		return ret;
+	}
+
+	fmt = v4l2_subdev_state_get_format(state, active_sink, 0);
+	crop = v4l2_subdev_state_get_crop(state, active_sink, 0);
+	compose = v4l2_subdev_state_get_compose(state, active_sink, 0);
+
+	fmt->width = MALI_C55_DEFAULT_WIDTH;
+	fmt->height = MALI_C55_DEFAULT_HEIGHT;
+	fmt->colorspace = V4L2_COLORSPACE_SRGB;
+	fmt->field = V4L2_FIELD_NONE;
+
+	if (active_sink == MALI_C55_RZR_SINK_PAD) {
+		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
+
+		crop->left = crop->top = 0;
+		crop->width = MALI_C55_DEFAULT_WIDTH;
+		crop->height = MALI_C55_DEFAULT_HEIGHT;
+
+		*compose = *crop;
+	} else {
+		fmt->code = MEDIA_BUS_FMT_SRGGB12_1X12;
+	}
+
+	/* Propagate the format to the source pad */
+	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD, 0) = *fmt;
+
+	return 0;
+}
+
+static int mali_c55_rzr_enum_mbus_code(struct v4l2_subdev *sd,
+				       struct v4l2_subdev_state *state,
+				       struct v4l2_subdev_mbus_code_enum *code)
+{
+	struct v4l2_mbus_framefmt *sink_fmt;
+	const struct mali_c55_isp_fmt *fmt;
+	unsigned int index = 0;
+	u32 sink_pad;
+
+	switch (code->pad) {
+	case MALI_C55_RZR_SINK_PAD:
+		if (code->index)
+			return -EINVAL;
+
+		code->code = MEDIA_BUS_FMT_RGB121212_1X36;
+
+		return 0;
+	case MALI_C55_RZR_SOURCE_PAD:
+		sink_pad = mali_c55_rzr_get_active_sink(state);
+		sink_fmt = v4l2_subdev_state_get_format(state, sink_pad, 0);
+
+		/*
+		 * If the active route is from the Bypass sink pad, then the
+		 * source pad is a simple passthrough of the sink format.
+		 */
+
+		if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
+			if (code->index)
+				return -EINVAL;
+
+			code->code = sink_fmt->code;
+			return 0;
+		}
+
+		/*
+		 * If the active route is from the non-bypass sink then we can
+		 * select either RGB or conversion to YUV.
+		 */
+
+		if (code->index >= ARRAY_SIZE(rzr_non_bypass_src_fmts))
+			return -EINVAL;
+
+		code->code = rzr_non_bypass_src_fmts[code->index];
+
+		return 0;
+	case MALI_C55_RZR_SINK_BYPASS_PAD:
+		for_each_mali_isp_fmt(fmt) {
+			if (index++ == code->index) {
+				code->code = fmt->code;
+				return 0;
+			}
+		}
+
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int mali_c55_rzr_enum_frame_size(struct v4l2_subdev *sd,
+					struct v4l2_subdev_state *state,
+					struct v4l2_subdev_frame_size_enum *fse)
+{
+	if (fse->index)
+		return -EINVAL;
+
+	fse->max_width = MALI_C55_MAX_WIDTH;
+	fse->max_height = MALI_C55_MAX_HEIGHT;
+	fse->min_width = MALI_C55_MIN_WIDTH;
+	fse->min_height = MALI_C55_MIN_HEIGHT;
+
+	return 0;
+}
+
+static int mali_c55_rzr_set_sink_fmt(struct v4l2_subdev *sd,
+				     struct v4l2_subdev_state *state,
+				     struct v4l2_subdev_format *format)
+{
+	struct v4l2_mbus_framefmt *fmt = &format->format;
+	struct v4l2_rect *rect;
+	unsigned int sink_pad;
+
+	/*
+	 * Clamp to min/max and then reset crop and compose rectangles to the
+	 * newly applied size.
+	 */
+	clamp_t(unsigned int, fmt->width,
+		MALI_C55_MIN_WIDTH, MALI_C55_MAX_WIDTH);
+	clamp_t(unsigned int, fmt->height,
+		MALI_C55_MIN_HEIGHT, MALI_C55_MAX_HEIGHT);
+
+	sink_pad = mali_c55_rzr_get_active_sink(state);
+	if (sink_pad == MALI_C55_RZR_SINK_PAD) {
+		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
+
+		rect = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD);
+		rect->left = 0;
+		rect->top = 0;
+		rect->width = fmt->width;
+		rect->height = fmt->height;
+
+		rect = v4l2_subdev_state_get_compose(state,
+						     MALI_C55_RZR_SINK_PAD);
+		rect->left = 0;
+		rect->top = 0;
+		rect->width = fmt->width;
+		rect->height = fmt->height;
+	} else {
+		/*
+		 * Make sure the media bus code is one of the supported
+		 * ISP input media bus codes.
+		 */
+		if (!mali_c55_isp_is_format_supported(fmt->code))
+			fmt->code = MALI_C55_DEFAULT_MEDIA_BUS_FMT;
+	}
+
+	*v4l2_subdev_state_get_format(state, sink_pad, 0) = *fmt;
+	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD, 0) = *fmt;
+
+	return 0;
+}
+
+static int mali_c55_rzr_set_source_fmt(struct v4l2_subdev *sd,
+				       struct v4l2_subdev_state *state,
+				       struct v4l2_subdev_format *format)
+{
+	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
+						    sd);
+	struct v4l2_mbus_framefmt *fmt = &format->format;
+	struct v4l2_mbus_framefmt *sink_fmt;
+	struct v4l2_rect *crop, *compose;
+	unsigned int sink_pad;
+	unsigned int i;
+
+	sink_pad = mali_c55_rzr_get_active_sink(state);
+	sink_fmt = v4l2_subdev_state_get_format(state, sink_pad, 0);
+	crop = v4l2_subdev_state_get_crop(state, sink_pad, 0);
+	compose = v4l2_subdev_state_get_compose(state, sink_pad, 0);
+
+	/* FR Bypass pipe. */
+
+	if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
+		/*
+		 * Format on the source pad is the same as the one on the
+		 * sink pad.
+		 */
+		fmt->code = sink_fmt->code;
+
+		/* RAW bypass disables scaling and cropping. */
+		crop->top = compose->top = 0;
+		crop->left = compose->left = 0;
+		fmt->width = crop->width = compose->width = sink_fmt->width;
+		fmt->height = crop->height = compose->height = sink_fmt->height;
+
+		*v4l2_subdev_state_get_format(state,
+					      MALI_C55_RZR_SOURCE_PAD) = *fmt;
+
+		return 0;
+	}
+
+	/* Regular processing pipe. */
+
+	for (i = 0; i < ARRAY_SIZE(rzr_non_bypass_src_fmts); i++) {
+		if (fmt->code == rzr_non_bypass_src_fmts[i])
+			break;
+	}
+
+	if (i == ARRAY_SIZE(rzr_non_bypass_src_fmts)) {
+		dev_dbg(rzr->mali_c55->dev,
+			"Unsupported mbus code 0x%x: using default\n",
+			fmt->code);
+		fmt->code = MEDIA_BUS_FMT_RGB121212_1X36;
+	}
+
+	/*
+	 * The source pad format size comes directly from the sink pad
+	 * compose rectangle.
+	 */
+	fmt->width = compose->width;
+	fmt->height = compose->height;
+
+	*v4l2_subdev_state_get_format(state, MALI_C55_RZR_SOURCE_PAD) = *fmt;
+
+	return 0;
+}
+
+static int mali_c55_rzr_set_fmt(struct v4l2_subdev *sd,
+				struct v4l2_subdev_state *state,
+				struct v4l2_subdev_format *format)
+{
+	/*
+	 * On sink pads fmt is either fixed for the 'regular' processing
+	 * pad or a RAW format or 20-bit wide RGB/YUV format for the FR bypass
+	 * pad.
+	 *
+	 * On source pad sizes are the result of crop+compose on the sink
+	 * pad sizes, while the format depends on the active route.
+	 */
+
+	if (format->pad != MALI_C55_RZR_SOURCE_PAD)
+		return mali_c55_rzr_set_sink_fmt(sd, state, format);
+
+	return mali_c55_rzr_set_source_fmt(sd, state, format);
+}
+
+static int mali_c55_rzr_get_selection(struct v4l2_subdev *sd,
+				      struct v4l2_subdev_state *state,
+				      struct v4l2_subdev_selection *sel)
+{
+	if (sel->pad != MALI_C55_RZR_SINK_PAD)
+		return -EINVAL;
+
+	if (sel->target != V4L2_SEL_TGT_CROP &&
+	    sel->target != V4L2_SEL_TGT_COMPOSE)
+		return -EINVAL;
+
+	sel->r = sel->target == V4L2_SEL_TGT_CROP
+	       ? *v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD)
+	       : *v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD);
+
+	return 0;
+}
+
+static int mali_c55_rzr_set_selection(struct v4l2_subdev *sd,
+				      struct v4l2_subdev_state *state,
+				      struct v4l2_subdev_selection *sel)
+{
+	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
+						    sd);
+	struct v4l2_mbus_framefmt *source_fmt;
+	struct v4l2_mbus_framefmt *sink_fmt;
+	struct v4l2_rect *crop, *compose;
+
+	if (sel->pad != MALI_C55_RZR_SINK_PAD)
+		return -EINVAL;
+
+	if (sel->target != V4L2_SEL_TGT_CROP &&
+	    sel->target != V4L2_SEL_TGT_COMPOSE)
+		return -EINVAL;
+
+	source_fmt = v4l2_subdev_state_get_format(state,
+						  MALI_C55_RZR_SOURCE_PAD);
+	sink_fmt = v4l2_subdev_state_get_format(state, MALI_C55_RZR_SINK_PAD);
+	crop = v4l2_subdev_state_get_crop(state, MALI_C55_RZR_SINK_PAD);
+	compose = v4l2_subdev_state_get_compose(state, MALI_C55_RZR_SINK_PAD);
+
+	/* RAW bypass disables crop/scaling. */
+	if (mali_c55_format_is_raw(source_fmt->code)) {
+		crop->top = compose->top = 0;
+		crop->left = compose->left = 0;
+		crop->width = compose->width = sink_fmt->width;
+		crop->height = compose->height = sink_fmt->height;
+
+		sel->r = sel->target == V4L2_SEL_TGT_CROP ? *crop : *compose;
+
+		return 0;
+	}
+
+	/* During streaming, it is allowed to only change the crop rectangle. */
+	if (rzr->streaming && sel->target != V4L2_SEL_TGT_CROP)
+		return -EINVAL;
+
+	 /*
+	  * Update the desired target and then clamp the crop rectangle to the
+	  * sink format sizes and the compose size to the crop sizes.
+	  */
+	if (sel->target == V4L2_SEL_TGT_CROP)
+		*crop = sel->r;
+	else
+		*compose = sel->r;
+
+	clamp_t(unsigned int, crop->left, 0,  sink_fmt->width);
+	clamp_t(unsigned int, crop->top, 0,  sink_fmt->height);
+	clamp_t(unsigned int, crop->width, MALI_C55_MIN_WIDTH,
+		sink_fmt->width - crop->left);
+	clamp_t(unsigned int, crop->height, MALI_C55_MIN_HEIGHT,
+		sink_fmt->height - crop->top);
+
+	if (rzr->streaming) {
+		/*
+		 * Apply at runtime a crop rectangle on the resizer's sink only
+		 * if it doesn't require re-programming the scaler output sizes
+		 * as it would require changing the output buffer sizes as well.
+		 */
+		if (sel->r.width < compose->width ||
+		    sel->r.height < compose->height)
+			return -EINVAL;
+
+		*crop = sel->r;
+		mali_c55_rzr_program(rzr, state);
+
+		return 0;
+	}
+
+	compose->left = 0;
+	compose->top = 0;
+	clamp_t(unsigned int, compose->left, 0,  sink_fmt->width);
+	clamp_t(unsigned int, compose->top, 0,  sink_fmt->height);
+	clamp_t(unsigned int, compose->width, crop->width / 8, crop->width);
+	clamp_t(unsigned int, compose->height, crop->height / 8, crop->height);
+
+	sel->r = sel->target == V4L2_SEL_TGT_CROP ? *crop : *compose;
+
+	return 0;
+}
+
+static int mali_c55_rzr_set_routing(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_state *state,
+				    enum v4l2_subdev_format_whence which,
+				    struct v4l2_subdev_krouting *routing)
+{
+	if (which == V4L2_SUBDEV_FORMAT_ACTIVE &&
+	    media_entity_is_streaming(&sd->entity))
+		return -EBUSY;
+
+	return __mali_c55_rzr_set_routing(sd, state, routing);
+}
+
+static const struct v4l2_subdev_pad_ops mali_c55_resizer_pad_ops = {
+	.enum_mbus_code		= mali_c55_rzr_enum_mbus_code,
+	.enum_frame_size	= mali_c55_rzr_enum_frame_size,
+	.get_fmt		= v4l2_subdev_get_fmt,
+	.set_fmt		= mali_c55_rzr_set_fmt,
+	.get_selection		= mali_c55_rzr_get_selection,
+	.set_selection		= mali_c55_rzr_set_selection,
+	.set_routing		= mali_c55_rzr_set_routing,
+};
+
+void mali_c55_rzr_start_stream(struct mali_c55_resizer *rzr)
+{
+	struct mali_c55 *mali_c55 = rzr->mali_c55;
+	struct v4l2_subdev *sd = &rzr->sd;
+	struct v4l2_subdev_state *state;
+	unsigned int sink_pad;
+
+	state = v4l2_subdev_lock_and_get_active_state(sd);
+
+	sink_pad = mali_c55_rzr_get_active_sink(state);
+	if (sink_pad == MALI_C55_RZR_SINK_BYPASS_PAD) {
+		/* Bypass FR pipe processing if the bypass route is active. */
+		mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
+				     MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK,
+				     MALI_C55_ISP_RAW_BYPASS_RAW_FR_BYPASS);
+		goto unlock_state;
+	}
+
+	/* Disable bypass and use regular processing. */
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_ISP_RAW_BYPASS,
+			     MALI_C55_ISP_RAW_BYPASS_FR_BYPASS_MASK, 0);
+	mali_c55_rzr_program(rzr, state);
+
+unlock_state:
+	rzr->streaming = true;
+	v4l2_subdev_unlock_state(state);
+}
+
+void mali_c55_rzr_stop_stream(struct mali_c55_resizer *rzr)
+{
+	struct v4l2_subdev *sd = &rzr->sd;
+	struct v4l2_subdev_state *state;
+
+	state = v4l2_subdev_lock_and_get_active_state(sd);
+	rzr->streaming = false;
+	v4l2_subdev_unlock_state(state);
+}
+
+static const struct v4l2_subdev_ops mali_c55_resizer_ops = {
+	.pad	= &mali_c55_resizer_pad_ops,
+};
+
+static int mali_c55_rzr_init_state(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_state *state)
+{
+	struct mali_c55_resizer *rzr = container_of(sd, struct mali_c55_resizer,
+						    sd);
+	struct v4l2_subdev_krouting routing = { };
+	struct v4l2_subdev_route *routes;
+	unsigned int i;
+	int ret;
+
+	routes = kcalloc(rzr->num_routes, sizeof(*routes), GFP_KERNEL);
+	if (!routes)
+		return -ENOMEM;
+
+	for (i = 0; i < rzr->num_routes; ++i) {
+		struct v4l2_subdev_route *route = &routes[i];
+
+		route->sink_pad = i
+				? MALI_C55_RZR_SINK_BYPASS_PAD
+				: MALI_C55_RZR_SINK_PAD;
+		route->source_pad = MALI_C55_RZR_SOURCE_PAD;
+		if (route->sink_pad != MALI_C55_RZR_SINK_BYPASS_PAD)
+			route->flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE;
+	}
+
+	routing.num_routes = rzr->num_routes;
+	routing.routes = routes;
+
+	ret = __mali_c55_rzr_set_routing(sd, state, &routing);
+	kfree(routes);
+
+	return ret;
+}
+
+static const struct v4l2_subdev_internal_ops mali_c55_resizer_internal_ops = {
+	.init_state = mali_c55_rzr_init_state,
+};
+
+static void mali_c55_resizer_program_coefficients(struct mali_c55 *mali_c55,
+						  unsigned int index)
+{
+	unsigned int scaler_filt_coefmem_addrs[][2] = {
+		[MALI_C55_RZR_FR] = {
+			0x034A8, /* hfilt */
+			0x044A8  /* vfilt */
+		},
+		[MALI_C55_RZR_DS] = {
+			0x014A8, /* hfilt */
+			0x024A8  /* vfilt */
+		},
+	};
+	unsigned int haddr = scaler_filt_coefmem_addrs[index][0];
+	unsigned int vaddr = scaler_filt_coefmem_addrs[index][1];
+	unsigned int i, j;
+
+	for (i = 0; i < MALI_C55_RESIZER_COEFS_NUM_BANKS; i++) {
+		for (j = 0; j < MALI_C55_RESIZER_COEFS_NUM_ENTRIES; j++) {
+			mali_c55_write(mali_c55, haddr,
+				mali_c55_scaler_h_filter_coefficients[i][j]);
+			mali_c55_write(mali_c55, vaddr,
+				mali_c55_scaler_v_filter_coefficients[i][j]);
+
+			haddr += 4;
+			vaddr += 4;
+		}
+	}
+}
+
+int mali_c55_register_resizers(struct mali_c55 *mali_c55)
+{
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < MALI_C55_NUM_RZRS; ++i) {
+		struct mali_c55_resizer *rzr = &mali_c55->resizers[i];
+		struct v4l2_subdev *sd = &rzr->sd;
+		unsigned int num_pads = MALI_C55_RZR_NUM_PADS;
+
+		rzr->id = i;
+		rzr->streaming = false;
+
+		if (rzr->id == MALI_C55_RZR_FR)
+			rzr->cap_dev = &mali_c55->cap_devs[MALI_C55_CAP_DEV_FR];
+		else
+			rzr->cap_dev = &mali_c55->cap_devs[MALI_C55_CAP_DEV_DS];
+
+		mali_c55_resizer_program_coefficients(mali_c55, i);
+
+		v4l2_subdev_init(sd, &mali_c55_resizer_ops);
+		sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE
+			  | V4L2_SUBDEV_FL_STREAMS;
+		sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
+		sd->owner = THIS_MODULE;
+		sd->internal_ops = &mali_c55_resizer_internal_ops;
+		snprintf(sd->name, ARRAY_SIZE(sd->name), "%s %s",
+			 MALI_C55_DRIVER_NAME, mali_c55_resizer_names[i]);
+
+		rzr->pads[MALI_C55_RZR_SINK_PAD].flags = MEDIA_PAD_FL_SINK;
+		rzr->pads[MALI_C55_RZR_SOURCE_PAD].flags = MEDIA_PAD_FL_SOURCE;
+
+		/* Only the FR pipe has a bypass pad. */
+		if (rzr->id == MALI_C55_RZR_FR) {
+			rzr->pads[MALI_C55_RZR_SINK_BYPASS_PAD].flags =
+							MEDIA_PAD_FL_SINK;
+			rzr->num_routes = 2;
+		} else {
+			num_pads -= 1;
+			rzr->num_routes = 1;
+		}
+
+		ret = media_entity_pads_init(&sd->entity, num_pads, rzr->pads);
+		if (ret)
+			return ret;
+
+		ret = v4l2_subdev_init_finalize(sd);
+		if (ret)
+			goto err_cleanup;
+
+		ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
+		if (ret)
+			goto err_cleanup;
+
+		rzr->mali_c55 = mali_c55;
+	}
+
+	return 0;
+
+err_cleanup:
+	for (; i >= 0; --i) {
+		struct mali_c55_resizer *rzr = &mali_c55->resizers[i];
+		struct v4l2_subdev *sd = &rzr->sd;
+
+		v4l2_subdev_cleanup(sd);
+		media_entity_cleanup(&sd->entity);
+	}
+
+	return ret;
+}
+
+void mali_c55_unregister_resizers(struct mali_c55 *mali_c55)
+{
+	unsigned int i;
+
+	for (i = 0; i < MALI_C55_NUM_RZRS; i++) {
+		struct mali_c55_resizer *resizer = &mali_c55->resizers[i];
+
+		if (!resizer->mali_c55)
+			continue;
+
+		v4l2_device_unregister_subdev(&resizer->sd);
+		v4l2_subdev_cleanup(&resizer->sd);
+		media_entity_cleanup(&resizer->sd.entity);
+	}
+}
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c b/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
new file mode 100644
index 000000000000..042851a4b42d
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-tpg.c
@@ -0,0 +1,424 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Mali-C55 ISP Driver - Test pattern generator
+ *
+ * Copyright (C) 2024 Ideas on Board Oy
+ */
+
+#include <linux/minmax.h>
+#include <linux/string.h>
+
+#include <media/media-entity.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-subdev.h>
+
+#include "mali-c55-common.h"
+#include "mali-c55-registers.h"
+
+#define MALI_C55_TPG_SRC_PAD		0
+#define MALI_C55_TPG_FIXED_HBLANK	0x20
+#define MALI_C55_TPG_MAX_VBLANK		0xFFFF
+#define MALI_C55_TPG_PIXEL_RATE		100000000
+
+static const char * const mali_c55_tpg_test_pattern_menu[] = {
+	"Flat field",
+	"Horizontal gradient",
+	"Vertical gradient",
+	"Vertical bars",
+	"Arbitrary rectangle",
+	"White frame on black field"
+};
+
+static const u32 mali_c55_tpg_mbus_codes[] = {
+	MEDIA_BUS_FMT_SRGGB16_1X16,
+	/*
+	 * This is a lie. In RGB mode the Test Pattern Generator actually output
+	 * 16-bits-per-colour data. However, RGB data follows one of the Bypass
+	 * paths which has a 12-bit limit at the insertion point, meaning it
+	 * would be truncated there to match the internal 12-bit format that
+	 * would be output from the debayering block. The same is true of RGB
+	 * data output by a sensor and streamed to the ISP's input port, however
+	 * in that case the ISP's input port requires that data be converted to
+	 * a 20-bit MSB aligned format. Given:
+	 *
+	 *	1. Our chosen topology represents the TPG as a subdevice
+	 *	   linked to the ISP's input port.
+	 *	2. We need to restrict the ISP's sink pad to only accepting that
+	 *	   20-bit RGB format from sensors / CSI-2 receivers.
+	 *	3. All the data ultimately ends up in the same format anyway and
+	 *	   these data from the TPG are purely internal to the ISP
+	 *
+	 * It seems best to reduce the programming complexity by simply
+	 * pretending that the TPG outputs data in the same format that the ISP
+	 * input port requires, even though it doesn't really.
+	 */
+	MEDIA_BUS_FMT_RGB202020_1X60,
+};
+
+static void __mali_c55_tpg_calc_vblank(struct v4l2_mbus_framefmt *format,
+				       int *def_vblank, int *min_vblank)
+{
+	unsigned int hts;
+	int tgt_fps;
+	int vblank;
+
+	hts = format->width + MALI_C55_TPG_FIXED_HBLANK;
+
+	/*
+	 * The ISP has minimum vertical blanking requirements that must be
+	 * adhered to by the TPG. The minimum is a function of the Iridix blocks
+	 * clocking requirements and the width of the image and horizontal
+	 * blanking, but if we assume the worst case iVariance and sVariance
+	 * values then it boils down to the below.
+	 */
+	*min_vblank = 15 + (120500 / hts);
+
+	/*
+	 * We need to set a sensible default vblank for whatever format height
+	 * we happen to be given from set_fmt(). This function just targets
+	 * an even multiple of 15fps. If we can't get 15fps, let's target 5fps.
+	 * If we can't get 5fps we'll take whatever the minimum vblank gives us.
+	 */
+	tgt_fps = MALI_C55_TPG_PIXEL_RATE / hts / (format->height + *min_vblank);
+
+	if (tgt_fps < 5)
+		vblank = *min_vblank;
+	else
+		vblank = MALI_C55_TPG_PIXEL_RATE / hts
+		       / max(rounddown(tgt_fps, 15), 5);
+
+	*def_vblank = ALIGN_DOWN(vblank, 2) - format->height;
+}
+
+static int mali_c55_tpg_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct mali_c55_tpg *tpg = container_of(ctrl->handler,
+						struct mali_c55_tpg,
+						ctrls.handler);
+	struct mali_c55 *mali_c55 = container_of(tpg, struct mali_c55, tpg);
+
+	switch (ctrl->id) {
+	case V4L2_CID_TEST_PATTERN:
+		mali_c55_write(mali_c55, MALI_C55_REG_TEST_GEN_CH0_PATTERN_TYPE,
+			       ctrl->val);
+		break;
+	case V4L2_CID_VBLANK:
+		mali_c55_update_bits(mali_c55, MALI_C55_REG_BLANKING,
+				     MALI_C55_REG_VBLANK_MASK, ctrl->val);
+		break;
+	default:
+		dev_err(mali_c55->dev, "invalid V4L2 control ID\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static const struct v4l2_ctrl_ops mali_c55_tpg_ctrl_ops = {
+	.s_ctrl = &mali_c55_tpg_s_ctrl,
+};
+
+static void mali_c55_tpg_configure(struct mali_c55 *mali_c55,
+				   struct v4l2_subdev *sd)
+{
+	struct v4l2_subdev_state *state;
+	struct v4l2_mbus_framefmt *fmt;
+
+	/*
+	 * hblank needs setting, but is a read-only control and thus won't be
+	 * called during __v4l2_ctrl_handler_setup(). Do it here instead.
+	 */
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_BLANKING,
+			     MALI_C55_REG_HBLANK_MASK,
+			     MALI_C55_TPG_FIXED_HBLANK);
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
+			     MALI_C55_REG_GEN_VIDEO_MULTI_MASK, 0x01);
+
+	state = v4l2_subdev_lock_and_get_active_state(sd);
+	fmt = v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD);
+
+	mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
+			     MALI_C55_TEST_PATTERN_RGB_MASK,
+			     fmt->code == MEDIA_BUS_FMT_RGB202020_1X60 ?
+					  0x01 : 0x0);
+
+	v4l2_subdev_unlock_state(state);
+}
+
+static int mali_c55_tpg_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct mali_c55_tpg *tpg = container_of(sd, struct mali_c55_tpg, sd);
+	struct mali_c55 *mali_c55 = container_of(tpg, struct mali_c55, tpg);
+
+	if (!enable) {
+		mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
+				     MALI_C55_TEST_PATTERN_ON_OFF, 0x00);
+		mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
+				     MALI_C55_REG_GEN_VIDEO_ON_MASK, 0x00);
+	} else {
+		/*
+		 * One might reasonably expect the framesize to be set here
+		 * given it's configurable in .set_fmt(), but it's done in the
+		 * ISP subdevice's .s_stream() instead, as the same register is
+		 * also used to indicate the size of the data coming from the
+		 * sensor.
+		 */
+		mali_c55_tpg_configure(mali_c55, sd);
+		__v4l2_ctrl_handler_setup(sd->ctrl_handler);
+
+		mali_c55_update_bits(mali_c55, MALI_C55_REG_TPG_CH0,
+				     MALI_C55_TEST_PATTERN_ON_OFF,
+				     MALI_C55_TEST_PATTERN_ON_OFF);
+		mali_c55_update_bits(mali_c55, MALI_C55_REG_GEN_VIDEO,
+				     MALI_C55_REG_GEN_VIDEO_ON_MASK,
+				     MALI_C55_REG_GEN_VIDEO_ON_MASK);
+	}
+
+	return 0;
+}
+
+static const struct v4l2_subdev_video_ops mali_c55_tpg_video_ops = {
+	.s_stream = &mali_c55_tpg_s_stream,
+};
+
+static int mali_c55_tpg_enum_mbus_code(struct v4l2_subdev *sd,
+				       struct v4l2_subdev_state *state,
+				       struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->pad >= sd->entity.num_pads)
+		return -EINVAL;
+
+	if (code->index >= ARRAY_SIZE(mali_c55_tpg_mbus_codes))
+		return -EINVAL;
+
+	code->code = mali_c55_tpg_mbus_codes[code->index];
+
+	return 0;
+}
+
+static int mali_c55_tpg_enum_frame_size(struct v4l2_subdev *sd,
+					struct v4l2_subdev_state *state,
+					struct v4l2_subdev_frame_size_enum *fse)
+{
+	if (fse->index > 0 || fse->pad > sd->entity.num_pads)
+		return -EINVAL;
+
+	fse->min_width = MALI_C55_MIN_WIDTH;
+	fse->max_width = MALI_C55_MAX_WIDTH;
+	fse->min_height = MALI_C55_MIN_HEIGHT;
+	fse->max_height = MALI_C55_MAX_HEIGHT;
+
+	return 0;
+}
+
+static int mali_c55_tpg_set_fmt(struct v4l2_subdev *sd,
+				struct v4l2_subdev_state *state,
+				struct v4l2_subdev_format *format)
+{
+	struct mali_c55_tpg *tpg = container_of(sd, struct mali_c55_tpg, sd);
+	struct v4l2_mbus_framefmt *fmt = &format->format;
+	int vblank_def, vblank_min;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(mali_c55_tpg_mbus_codes); i++) {
+		if (fmt->code == mali_c55_tpg_mbus_codes[i])
+			break;
+	}
+
+	if (i == ARRAY_SIZE(mali_c55_tpg_mbus_codes))
+		fmt->code = MEDIA_BUS_FMT_SRGGB16_1X16;
+
+	/*
+	 * The TPG says that the test frame timing generation logic expects a
+	 * minimum framesize of 4x4 pixels, but given the rest of the ISP can't
+	 * handle anything smaller than 128x128 it seems pointless to allow a
+	 * smaller frame.
+	 */
+	clamp_t(unsigned int, fmt->width, MALI_C55_MIN_WIDTH,
+		MALI_C55_MAX_WIDTH);
+	clamp_t(unsigned int, fmt->height, MALI_C55_MIN_HEIGHT,
+		MALI_C55_MAX_HEIGHT);
+
+	*v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD) = *fmt;
+
+	__mali_c55_tpg_calc_vblank(fmt, &vblank_def, &vblank_min);
+	__v4l2_ctrl_modify_range(tpg->ctrls.vblank, vblank_min,
+				 MALI_C55_TPG_MAX_VBLANK, 1, vblank_def);
+	__v4l2_ctrl_s_ctrl(tpg->ctrls.vblank, vblank_def);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_pad_ops mali_c55_tpg_pad_ops = {
+	.enum_mbus_code		= mali_c55_tpg_enum_mbus_code,
+	.enum_frame_size	= mali_c55_tpg_enum_frame_size,
+	.get_fmt		= v4l2_subdev_get_fmt,
+	.set_fmt		= mali_c55_tpg_set_fmt,
+};
+
+static const struct v4l2_subdev_ops mali_c55_tpg_ops = {
+	.video	= &mali_c55_tpg_video_ops,
+	.pad	= &mali_c55_tpg_pad_ops,
+};
+
+static int mali_c55_tpg_init_state(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_state *sd_state)
+{
+	struct v4l2_mbus_framefmt *fmt;
+
+	fmt = v4l2_subdev_state_get_format(sd_state, MALI_C55_TPG_SRC_PAD);
+
+	fmt->width = MALI_C55_DEFAULT_WIDTH;
+	fmt->height = MALI_C55_DEFAULT_HEIGHT;
+	fmt->field = V4L2_FIELD_NONE;
+	fmt->code = MEDIA_BUS_FMT_SRGGB16_1X16;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_internal_ops mali_c55_tpg_internal_ops = {
+	.init_state = mali_c55_tpg_init_state,
+};
+
+static int mali_c55_tpg_init_controls(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_tpg_ctrls *ctrls = &mali_c55->tpg.ctrls;
+	struct v4l2_subdev *sd = &mali_c55->tpg.sd;
+	struct v4l2_mbus_framefmt *format;
+	struct v4l2_subdev_state *state;
+	int vblank_def, vblank_min;
+	int ret;
+
+	state = v4l2_subdev_lock_and_get_active_state(sd);
+	format = v4l2_subdev_state_get_format(state, MALI_C55_TPG_SRC_PAD);
+
+	ret = v4l2_ctrl_handler_init(&ctrls->handler, 1);
+	if (ret)
+		goto err_unlock;
+
+	ctrls->test_pattern = v4l2_ctrl_new_std_menu_items(&ctrls->handler,
+				&mali_c55_tpg_ctrl_ops, V4L2_CID_TEST_PATTERN,
+				ARRAY_SIZE(mali_c55_tpg_test_pattern_menu) - 1,
+				0, 3, mali_c55_tpg_test_pattern_menu);
+
+	/*
+	 * We fix hblank at the minimum allowed value and control framerate
+	 * solely through the vblank control.
+	 */
+	ctrls->hblank = v4l2_ctrl_new_std(&ctrls->handler,
+				&mali_c55_tpg_ctrl_ops,
+				V4L2_CID_HBLANK, MALI_C55_TPG_FIXED_HBLANK,
+				MALI_C55_TPG_FIXED_HBLANK, 1,
+				MALI_C55_TPG_FIXED_HBLANK);
+	if (ctrls->hblank)
+		ctrls->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
+	__mali_c55_tpg_calc_vblank(format, &vblank_def, &vblank_min);
+	ctrls->vblank = v4l2_ctrl_new_std(&ctrls->handler,
+					  &mali_c55_tpg_ctrl_ops,
+					  V4L2_CID_VBLANK, vblank_min,
+					  MALI_C55_TPG_MAX_VBLANK, 1,
+					  vblank_def);
+
+	if (ctrls->handler.error) {
+		dev_err(mali_c55->dev, "Error during v4l2 controls init\n");
+		ret = ctrls->handler.error;
+		goto err_free_handler;
+	}
+
+	ctrls->handler.lock = &mali_c55->tpg.lock;
+	mali_c55->tpg.sd.ctrl_handler = &ctrls->handler;
+
+	v4l2_subdev_unlock_state(state);
+
+	return 0;
+
+err_free_handler:
+	v4l2_ctrl_handler_free(&ctrls->handler);
+err_unlock:
+	v4l2_subdev_unlock_state(state);
+	return ret;
+}
+
+int mali_c55_register_tpg(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_tpg *tpg = &mali_c55->tpg;
+	struct v4l2_subdev *sd = &tpg->sd;
+	struct media_pad *pad = &tpg->pad;
+	int ret;
+
+	mutex_init(&tpg->lock);
+
+	v4l2_subdev_init(sd, &mali_c55_tpg_ops);
+	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	sd->entity.function = MEDIA_ENT_F_CAM_SENSOR;
+	sd->owner = THIS_MODULE;
+	sd->internal_ops = &mali_c55_tpg_internal_ops;
+	strscpy(sd->name, MALI_C55_DRIVER_NAME " tpg", sizeof(sd->name));
+
+	pad->flags = MEDIA_PAD_FL_SOURCE | MEDIA_PAD_FL_MUST_CONNECT;
+	ret = media_entity_pads_init(&sd->entity, 1, pad);
+	if (ret) {
+		dev_err(mali_c55->dev,
+			"Failed to initialize media entity pads\n");
+		goto err_destroy_mutex;
+	}
+
+	ret = v4l2_subdev_init_finalize(sd);
+	if (ret)
+		goto err_cleanup_media_entity;
+
+	ret = mali_c55_tpg_init_controls(mali_c55);
+	if (ret) {
+		dev_err(mali_c55->dev,
+			"Error initialising controls\n");
+		goto err_cleanup_subdev;
+	}
+
+	ret = v4l2_device_register_subdev(&mali_c55->v4l2_dev, sd);
+	if (ret) {
+		dev_err(mali_c55->dev, "Failed to register tpg subdev\n");
+		goto err_free_ctrl_handler;
+	}
+
+	/*
+	 * By default the colour settings lead to a very dim image that is
+	 * nearly indistinguishable from black on some monitor settings. Ramp
+	 * them up a bit so the image is brighter.
+	 */
+	mali_c55_write(mali_c55, MALI_C55_REG_TPG_R_BACKGROUND,
+		       MALI_C55_TPG_BACKGROUND_MAX);
+	mali_c55_write(mali_c55, MALI_C55_REG_TPG_G_BACKGROUND,
+		       MALI_C55_TPG_BACKGROUND_MAX);
+	mali_c55_write(mali_c55, MALI_C55_REG_TPG_B_BACKGROUND,
+		       MALI_C55_TPG_BACKGROUND_MAX);
+
+	tpg->mali_c55 = mali_c55;
+
+	return 0;
+
+err_free_ctrl_handler:
+	v4l2_ctrl_handler_free(&tpg->ctrls.handler);
+err_cleanup_subdev:
+	v4l2_subdev_cleanup(sd);
+err_cleanup_media_entity:
+	media_entity_cleanup(&sd->entity);
+err_destroy_mutex:
+	mutex_destroy(&tpg->lock);
+
+	return ret;
+}
+
+void mali_c55_unregister_tpg(struct mali_c55 *mali_c55)
+{
+	struct mali_c55_tpg *tpg = &mali_c55->tpg;
+
+	if (!tpg->mali_c55)
+		return;
+
+	v4l2_device_unregister_subdev(&tpg->sd);
+	v4l2_subdev_cleanup(&tpg->sd);
+	media_entity_cleanup(&tpg->sd.entity);
+	v4l2_ctrl_handler_free(&tpg->ctrls.handler);
+	mutex_destroy(&tpg->lock);
+}