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[1/2] drm/bridge: add Silicon Image SiI9234 driver

Message ID 1501746323-5254-2-git-send-email-m.purski@samsung.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Maciej Purski Aug. 3, 2017, 7:45 a.m. UTC
SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
It is controlled via I2C bus. Its interaction with other
devices in video pipeline is performed mainly on HW level.
The only interaction it does on device driver level is
filtering-out unsupported video modes, it exposes drm_bridge
interface to perform this operation.

This patch is based on the code refactored by Tomasz Stanislawski
<t.stanislaws@samsung.com>, which was initially developed by:
Adam Hampson <ahampson@sta.samsung.com>
Erik Gilling <konkers@android.com>
Shankar Bandal <shankar.b@samsung.com>
Dharam Kumar <dharam.kr@samsung.com>

Signed-off-by: Maciej Purski <m.purski@samsung.com>
---
 .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
 drivers/gpu/drm/bridge/Kconfig                     |    8 +
 drivers/gpu/drm/bridge/Makefile                    |    1 +
 drivers/gpu/drm/bridge/sii9234.c                   | 1019 ++++++++++++++++++++
 4 files changed, 1048 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/sii9234.txt
 create mode 100644 drivers/gpu/drm/bridge/sii9234.c

Comments

Laurent Pinchart Aug. 3, 2017, 10:24 a.m. UTC | #1
Hi Maciej,

Thank you for the patch.

On Thursday 03 Aug 2017 09:45:22 Maciej Purski wrote:
> SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
> It is controlled via I2C bus. Its interaction with other
> devices in video pipeline is performed mainly on HW level.
> The only interaction it does on device driver level is
> filtering-out unsupported video modes, it exposes drm_bridge
> interface to perform this operation.
> 
> This patch is based on the code refactored by Tomasz Stanislawski
> <t.stanislaws@samsung.com>, which was initially developed by:
> Adam Hampson <ahampson@sta.samsung.com>
> Erik Gilling <konkers@android.com>
> Shankar Bandal <shankar.b@samsung.com>
> Dharam Kumar <dharam.kr@samsung.com>
> 
> Signed-off-by: Maciej Purski <m.purski@samsung.com>
> ---
>  .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
>  drivers/gpu/drm/bridge/Kconfig                     |    8 +
>  drivers/gpu/drm/bridge/Makefile                    |    1 +
>  drivers/gpu/drm/bridge/sii9234.c                   | 1019 +++++++++++++++++
>  4 files changed, 1048 insertions(+)
>  create mode 100644
> Documentation/devicetree/bindings/display/bridge/sii9234.txt create mode
> 100644 drivers/gpu/drm/bridge/sii9234.c
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> b/Documentation/devicetree/bindings/display/bridge/sii9234.txt new file
> mode 100644
> index 0000000..2cdf286
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt

DT reviewers might ask you to submit DT bindings as a separate patch.

> @@ -0,0 +1,20 @@
> +SiI9234 Mobile HD Link Transmitter
> +
> +Required properties:
> +- compatible : "sil,sii9234".
> +- reg : I2C address for TPI interface, use 0x39
> +- vcc-supply : regulator that supplies the chip

Is there a single power supply only ? Transceivers usually have at least one 
digital and one analog power supply.

> +- interrupts, interrupt-parent: interrupt specifier of INT pin
> +- reset-gpios: gpio specifier of RESET pin

Is this mandatory to connect the reset pin to the SoC ?

You should use the OF graph DT bindings (a.k.a. ports) to describe the data 
connections with the rest of the system. I'm not familiar with this chip, but 
I assume it should have one input port connected to the SoC and one output 
port connected to an HDMI connector DT node.

> +Additional compatible properties are also allowed.

How so ? :-)

> +
> +Example:
> +	sii9234@39 {
> +		compatible = "sil,sii9234";
> +		reg = <0x39>;
> +		vcc-supply = <&vsil>;
> +		reset-gpios = <&gpf3 4 GPIO_ACTIVE_HIGH>;
> +		interrupt-parent = <&gpf3>;
> +		interrupts = <5 IRQ_TYPE_LEVEL_HIGH>;
> +	};
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index adf9ae0..f5784e5 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -100,6 +100,14 @@ config DRM_TI_TFP410
>  	---help---
>  	  Texas Instruments TFP410 DVI/HDMI Transmitter driver
> 
> +config DRM_SII9234
> +	tristate "Silicon Image SII9234 Driver"
> +	depends on I2C

You can depend on OF too as the driver doesn't currently support any other 
method.

> +	help
> +	  Say Y here if you want support for the MHL interface.
> +	  It is an I2C driver, that detects connection of MHL bridge
> +	  and starts encapsulation of HDMI signal.
> +
>  source "drivers/gpu/drm/bridge/analogix/Kconfig"
> 
>  source "drivers/gpu/drm/bridge/adv7511/Kconfig"
> diff --git a/drivers/gpu/drm/bridge/Makefile
> b/drivers/gpu/drm/bridge/Makefile index defcf1e..e3d5eb0 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -6,6 +6,7 @@ obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
>  obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
>  obj-$(CONFIG_DRM_SIL_SII8620) += sil-sii8620.o
>  obj-$(CONFIG_DRM_SII902X) += sii902x.o
> +obj-$(CONFIG_DRM_SII9234) += sii9234.o
>  obj-$(CONFIG_DRM_TOSHIBA_TC358767) += tc358767.o
>  obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
>  obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
> diff --git a/drivers/gpu/drm/bridge/sii9234.c
> b/drivers/gpu/drm/bridge/sii9234.c new file mode 100644
> index 0000000..9c436e7
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/sii9234.c
> @@ -0,0 +1,1019 @@
> +/*
> + * Copyright (C) 2014 Samsung Electronics
> + *
> + * Author: Tomasz Stanislawski <t.stanislaws@samsung.com>
> + *
> + * Based on sii9234 driver created by:
> + *    Adam Hampson <ahampson@sta.samsung.com>
> + *    Erik Gilling <konkers@android.com>
> + *    Shankar Bandal <shankar.b@samsung.com>
> + *    Dharam Kumar <dharam.kr@samsung.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program
> + *
> + */
> +#include <drm/bridge/mhl.h>
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_edid.h>
> +
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/gpio.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/wait.h>
> +#include <linux/file.h>
> +#include <linux/uaccess.h>
> +#include <linux/proc_fs.h>
> +#include <linux/extcon.h>
> +#include <linux/of.h>
> +#include <linux/of_gpio.h>
> +#include <linux/extcon.h>
> +#include <linux/regulator/machine.h>

Could you please order these alphabetically ?

> +
> +/* MHL Tx registers and bits */
> +#define MHL_TX_SRST                     0x05
> +#define MHL_TX_SYSSTAT_REG              0x09
> +#define MHL_TX_INTR1_REG                0x71
> +#define MHL_TX_INTR4_REG                0x74
> +#define MHL_TX_INTR1_ENABLE_REG         0x75
> +#define MHL_TX_INTR4_ENABLE_REG         0x78
> +#define MHL_TX_INT_CTRL_REG             0x79
> +#define MHL_TX_TMDS_CCTRL               0x80
> +#define MHL_TX_DISC_CTRL1_REG           0x90
> +#define MHL_TX_DISC_CTRL2_REG           0x91
> +#define MHL_TX_DISC_CTRL3_REG           0x92
> +#define MHL_TX_DISC_CTRL4_REG		0x93
> +#define MHL_TX_DISC_CTRL5_REG           0x94
> +#define MHL_TX_DISC_CTRL6_REG           0x95
> +#define MHL_TX_DISC_CTRL7_REG           0x96
> +#define MHL_TX_DISC_CTRL8_REG		0x97
> +#define MHL_TX_STAT2_REG                0x99
> +#define MHL_TX_MHLTX_CTL1_REG           0xA0
> +#define MHL_TX_MHLTX_CTL2_REG           0xA1
> +#define MHL_TX_MHLTX_CTL4_REG           0xA3
> +#define MHL_TX_MHLTX_CTL6_REG           0xA5
> +#define MHL_TX_MHLTX_CTL7_REG           0xA6
> +
> +
> +#define RSEN_STATUS			BIT(2)
> +#define HPD_CHANGE_INT			BIT(6)
> +#define RSEN_CHANGE_INT			BIT(5)
> +#define RGND_READY_INT			BIT(6)
> +#define VBUS_LOW_INT			BIT(5)
> +#define CBUS_LKOUT_INT			BIT(4)
> +#define MHL_DISC_FAIL_INT		BIT(3)
> +#define MHL_EST_INT			BIT(2)
> +#define HPD_CHANGE_INT_MASK		BIT(6)
> +#define RSEN_CHANGE_INT_MASK		BIT(5)
> +
> +#define RGND_READY_MASK			BIT(6)
> +#define CBUS_LKOUT_MASK			BIT(4)
> +#define MHL_DISC_FAIL_MASK		BIT(3)
> +#define MHL_EST_MASK			BIT(2)
> +
> +#define SKIP_GND			BIT(6)
> +
> +#define ATT_THRESH_SHIFT		0x04
> +#define ATT_THRESH_MASK			(0x03 << ATT_THRESH_SHIFT)
> +#define USB_D_OEN			BIT(3)
> +#define DEGLITCH_TIME_MASK		0x07
> +#define DEGLITCH_TIME_2MS		0
> +#define DEGLITCH_TIME_4MS		1
> +#define DEGLITCH_TIME_8MS		2
> +#define DEGLITCH_TIME_16MS		3
> +#define DEGLITCH_TIME_40MS		4
> +#define DEGLITCH_TIME_50MS		5
> +#define DEGLITCH_TIME_60MS		6
> +#define DEGLITCH_TIME_128MS		7
> +
> +#define USB_D_OVR			BIT(7)
> +#define USB_ID_OVR			BIT(6)
> +#define DVRFLT_SEL			BIT(5)
> +#define BLOCK_RGND_INT			BIT(4)
> +#define SKIP_DEG			BIT(3)
> +#define CI2CA_POL			BIT(2)
> +#define CI2CA_WKUP			BIT(1)
> +#define SINGLE_ATT			BIT(0)
> +
> +#define USB_D_ODN			BIT(5)
> +#define VBUS_CHECK			BIT(2)
> +#define RGND_INTP_MASK			0x03
> +#define RGND_INTP_OPEN			0
> +#define RGND_INTP_2K			1
> +#define RGND_INTP_1K			2
> +#define RGND_INTP_SHORT			3
> +
> +
> +/* HDMI registers */
> +#define HDMI_RX_TMDS0_CCTRL1_REG	0x10
> +#define HDMI_RX_TMDS_CLK_EN_REG		0x11
> +#define HDMI_RX_TMDS_CH_EN_REG		0x12
> +#define HDMI_RX_PLL_CALREFSEL_REG	0x17
> +#define HDMI_RX_PLL_VCOCAL_REG		0x1A
> +#define HDMI_RX_EQ_DATA0_REG		0x22
> +#define HDMI_RX_EQ_DATA1_REG		0x23
> +#define HDMI_RX_EQ_DATA2_REG		0x24
> +#define HDMI_RX_EQ_DATA3_REG		0x25
> +#define HDMI_RX_EQ_DATA4_REG		0x26
> +#define HDMI_RX_TMDS_ZONE_CTRL_REG	0x4C
> +#define HDMI_RX_TMDS_MODE_CTRL_REG	0x4D
> +
> +/* CBUS registers */
> +#define CBUS_INT_STATUS_1_REG		0x08
> +#define CBUS_INTR1_ENABLE_REG		0x09
> +#define CBUS_MSC_REQ_ABORT_REASON_REG	0x0D
> +#define SET_HPD_DOWNSTREAM		(1<<6)
> +#define CBUS_INT_STATUS_2_REG		0x1E
> +#define CBUS_INTR2_ENABLE_REG		0x1F
> +#define CBUS_LINK_CONTROL_2_REG		0x31
> +#define CBUS_DEVCAP_DEV_STATE		0x80
> +#define CBUS_DEVCAP_MHL_VERSION		0x81
> +#define CBUS_DEVCAP_DEV_CAT		0x82
> +#define CBUS_DEVCAP_ADOPTER_ID_H	0x83
> +#define CBUS_DEVCAP_ADOPTER_ID_L	0x84
> +#define CBUS_DEVCAP_VID_LINK_MODE	0x85
> +#define CBUS_DEVCAP_AUD_LINK_MODE	0x86
> +#define CBUS_DEVCAP_VIDEO_TYPE		0x87
> +#define CBUS_DEVCAP_LOG_DEV_MAP		0x88
> +#define CBUS_DEVCAP_BANDWIDTH		0x89
> +#define CBUS_DEVCAP_DEV_FEATURE_FLAG	0x8A
> +#define CBUS_DEVCAP_DEVICE_ID_H		0x8B
> +#define CBUS_DEVCAP_DEVICE_ID_L		0x8C
> +#define CBUS_DEVCAP_SCRATCHPAD_SIZE	0x8D
> +#define CBUS_DEVCAP_INT_STAT_SIZE	0x8E
> +#define CBUS_DEVCAP_RESERVED		0x8F
> +#define CBUS_MHL_STATUS_REG_0		0xB0
> +#define CBUS_MHL_STATUS_REG_1		0xB1
> +
> +/* TPI registers */
> +#define TPI_DPD_REG			0x3D
> +
> +/* timeouts */
> +#define T_SRC_VBUS_CBUS_TO_STABLE	200
> +#define T_SRC_CBUS_FLOAT		100
> +#define T_SRC_CBUS_DEGLITCH		2
> +#define T_SRC_RXSENSE_DEGLITCH		110
> +#define MHL1_MAX_CLK			75000
> +
> +enum sii9234_state {
> +	ST_OFF,
> +	ST_D3,
> +	ST_RGND_INIT,
> +	ST_RGND_1K,
> +	ST_RSEN_HIGH,
> +	ST_MHL_ESTABLISHED,
> +	ST_FAILURE_DISCOVERY,
> +	ST_FAILURE,
> +};
> +
> +struct sii9234 {
> +	struct i2c_client *client[4];
> +	struct drm_bridge bridge;
> +	struct device *dev;
> +	struct gpio_desc *gpio_reset;
> +	int i2c_error;
> +	struct regulator *vcc_supply;
> +
> +	enum sii9234_state state;
> +	struct mutex lock;
> +};
> +
> +enum sii9234_client_id {
> +	I2C_MHL,
> +	I2C_TPI,
> +	I2C_HDMI,
> +	I2C_CBUS,
> +};
> +
> +static char *sii9234_client_name[] = {
> +	[I2C_MHL] = "MHL",
> +	[I2C_TPI] = "TPI",
> +	[I2C_HDMI] = "HDMI",
> +	[I2C_CBUS] = "CBUS",
> +};
> +
> +static int sii9234_writeb(struct sii9234 *ctx, int id, int offset,
> +			    int value)
> +{
> +	int ret;
> +	struct i2c_client *client = ctx->client[id];
> +
> +	if (ctx->i2c_error)
> +		return ctx->i2c_error;
> +
> +	ret = i2c_smbus_write_byte_data(client, offset, value);
> +	if (ret < 0)
> +		dev_err(ctx->dev, "writeb: %4s[0x%02x] <- 0x%02x\n",
> +			sii9234_client_name[id], offset, value);
> +	ctx->i2c_error = ret;
> +	return ret;
> +}
> +
> +static int sii9234_writebm(struct sii9234 *ctx, int id, int offset,
> +			    int value, int mask)
> +{
> +	int ret;
> +	struct i2c_client *client = ctx->client[id];
> +
> +	if (ctx->i2c_error)
> +		return ctx->i2c_error;
> +
> +	ret = i2c_smbus_write_byte(client, offset);
> +	if (ret < 0) {
> +		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
> +			sii9234_client_name[id], offset, value);
> +		ctx->i2c_error = ret;
> +		return ret;
> +	}
> +
> +	ret = i2c_smbus_read_byte(client);
> +	if (ret < 0) {
> +		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
> +			sii9234_client_name[id], offset, value);
> +		ctx->i2c_error = ret;
> +		return ret;
> +	}
> +
> +	value = (value & mask) | (ret & ~mask);
> +
> +	ret = i2c_smbus_write_byte_data(client, offset, value);
> +	if (ret < 0) {
> +		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
> +			sii9234_client_name[id], offset, value);
> +		ctx->i2c_error = ret;
> +	}
> +	return ret;
> +}
> +
> +static int sii9234_readb(struct sii9234 *ctx, int id, int offset)
> +{
> +	int ret;
> +	struct i2c_client *client = ctx->client[id];
> +
> +	if (ctx->i2c_error)
> +		return ctx->i2c_error;
> +
> +	ret = i2c_smbus_write_byte(client, offset);
> +	if (ret < 0) {
> +		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
> +			sii9234_client_name[id], offset);
> +		ctx->i2c_error = ret;
> +		return ret;
> +	}
> +
> +	ret = i2c_smbus_read_byte(client);
> +	if (ret < 0) {
> +		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
> +			sii9234_client_name[id], offset);
> +		ctx->i2c_error = ret;
> +	}
> +
> +	return ret;
> +}
> +
> +static int sii9234_clear_error(struct sii9234 *ctx)
> +{
> +	int ret = ctx->i2c_error;
> +
> +	ctx->i2c_error = 0;
> +	return ret;
> +}
> +
> +#define mhl_tx_writeb(sii9234, offset, value) \
> +	sii9234_writeb(sii9234, I2C_MHL, offset, value)
> +#define mhl_tx_writebm(sii9234, offset, value, mask) \
> +	sii9234_writebm(sii9234, I2C_MHL, offset, value, mask)
> +#define mhl_tx_readb(sii9234, offset) \
> +	sii9234_readb(sii9234, I2C_MHL, offset)
> +#define cbus_writeb(sii9234, offset, value) \
> +	sii9234_writeb(sii9234, I2C_CBUS, offset, value)
> +#define cbus_writebm(sii9234, offset, value, mask) \
> +	sii9234_writebm(sii9234, I2C_CBUS, offset, value, mask)
> +#define cbus_readb(sii9234, offset) \
> +	sii9234_readb(sii9234, I2C_CBUS, offset)
> +#define hdmi_writeb(sii9234, offset, value) \
> +	sii9234_writeb(sii9234, I2C_HDMI, offset, value)
> +#define hdmi_writebm(sii9234, offset, value, mask) \
> +	sii9234_writebm(sii9234, I2C_HDMI, offset, value, mask)
> +#define hdmi_readb(sii9234, offset) \
> +	sii9234_readb(sii9234, I2C_HDMI, offset)
> +#define tpi_writeb(sii9234, offset, value) \
> +	sii9234_writeb(sii9234, I2C_TPI, offset, value)
> +#define tpi_writebm(sii9234, offset, value, mask) \
> +	sii9234_writebm(sii9234, I2C_TPI, offset, value, mask)
> +#define tpi_readb(sii9234, offset) \
> +	sii9234_readb(sii9234, I2C_TPI, offset)
> +
> +static u8 sii9234_tmds_control(struct sii9234 *ctx, bool enable)
> +{
> +	mhl_tx_writebm(ctx, MHL_TX_TMDS_CCTRL, enable ? ~0 : 0, 0x10);
> +	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, enable ? ~0 : 0, 0x30);
> +	return sii9234_clear_error(ctx);
> +}
> +
> +static int sii9234_cbus_reset(struct sii9234 *ctx)
> +{
> +	int i;

i is never negative, you can make it an unsigned int.

> +
> +	/* Reset CBUS */
> +	mhl_tx_writebm(ctx, MHL_TX_SRST, ~0, 1 << 3);
> +	/* CBUS deglitch - 2ms */
> +	msleep(T_SRC_CBUS_DEGLITCH);
> +	mhl_tx_writebm(ctx, MHL_TX_SRST, 0, 1 << 3);
> +
> +	for (i = 0; i < 4; i++) {
> +		/* Enable WRITE_STAT interrupt for writes to all
> +		 * 4 MSC Status registers.
> +		 */
> +		cbus_writeb(ctx, 0xE0 + i, 0xF2);
> +		/* Enable SET_INT interrupt for writes to all
> +		 * 4 MSC Interrupt registers.
> +		 */
> +		cbus_writeb(ctx, 0xF0 + i, 0xF2);
> +	}
> +
> +	return sii9234_clear_error(ctx);
> +}
> +
> +/* require to chek mhl imformation of samsung in cbus_init_register*/

You need a space before */, here and everywhere else in the driver.

> +static int sii9234_cbus_init(struct sii9234 *ctx)
> +{
> +	cbus_writeb(ctx, 0x07, 0xF2);
> +	cbus_writeb(ctx, 0x40, 0x03);
> +	cbus_writeb(ctx, 0x42, 0x06);
> +	cbus_writeb(ctx, 0x36, 0x0C);
> +	cbus_writeb(ctx, 0x3D, 0xFD);
> +	cbus_writeb(ctx, 0x1C, 0x01);
> +	cbus_writeb(ctx, 0x1D, 0x0F);
> +	cbus_writeb(ctx, 0x44, 0x02);
> +	/* Setup our devcap */
> +	/* To meet cts 6.3.10.1 spec */
> +	cbus_writeb(ctx, CBUS_DEVCAP_DEV_STATE, 0x00);
> +	/* mhl version 1.1 */
> +	cbus_writeb(ctx, CBUS_DEVCAP_MHL_VERSION, 0x11);
> +	cbus_writeb(ctx, CBUS_DEVCAP_DEV_CAT, 0x02);
> +	cbus_writeb(ctx, CBUS_DEVCAP_ADOPTER_ID_H, 0x01);
> +	cbus_writeb(ctx, CBUS_DEVCAP_ADOPTER_ID_L, 0x41);
> +	/* YCbCr444, RGB444 */
> +	cbus_writeb(ctx, CBUS_DEVCAP_VID_LINK_MODE, 0x03);
> +	cbus_writeb(ctx, CBUS_DEVCAP_VIDEO_TYPE, 0);
> +	cbus_writeb(ctx, CBUS_DEVCAP_LOG_DEV_MAP, 0x80);
> +	cbus_writeb(ctx, CBUS_DEVCAP_BANDWIDTH, 0x0F);
> +	cbus_writeb(ctx, CBUS_DEVCAP_DEV_FEATURE_FLAG, 0x07);
> +	cbus_writeb(ctx, CBUS_DEVCAP_DEVICE_ID_H, 0x0);
> +	cbus_writeb(ctx, CBUS_DEVCAP_DEVICE_ID_L, 0x0);
> +	cbus_writeb(ctx, CBUS_DEVCAP_SCRATCHPAD_SIZE, 0x10);
> +	cbus_writeb(ctx, CBUS_DEVCAP_INT_STAT_SIZE, 0x33);
> +	cbus_writeb(ctx, CBUS_DEVCAP_RESERVED, 0);
> +	cbus_writebm(ctx, 0x31, 0x0C, 0x0C);
> +	cbus_writeb(ctx, 0x30, 0x01);
> +	cbus_writebm(ctx, 0x3C, 0x30, 0x38);
> +	cbus_writebm(ctx, 0x22, 0x0D, 0x0F);
> +	cbus_writebm(ctx, 0x2E, 0x15, 0x15);
> +	cbus_writeb(ctx, CBUS_INTR1_ENABLE_REG, 0);
> +	cbus_writeb(ctx, CBUS_INTR2_ENABLE_REG, 0);
> +
> +	return sii9234_clear_error(ctx);
> +}
> +
> +static void force_usb_id_switch_open(struct sii9234 *ctx)
> +{
> +	/*Disable CBUS discovery */

You need a space after /*, here and everywhere else in the driver.

> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0, 0x01);
> +	/*Force USB ID switch to open */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
> +	/*Force upstream HPD to 0 when not in MHL mode. */
> +	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x30);
> +}
> +
> +static void release_usb_id_switch_open(struct sii9234 *ctx)
> +{
> +	msleep(T_SRC_CBUS_FLOAT);
> +	/* clear USB ID switch to open */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0, USB_ID_OVR);
> +	/* Enable CBUS discovery */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 0x01);
> +}
> +
> +static int sii9234_power_init(struct sii9234 *ctx)
> +{
> +	/* Force the SiI9234 into the D0 state. */
> +	tpi_writeb(ctx, TPI_DPD_REG, 0x3F);
> +	/* Enable TxPLL Clock */
> +	hdmi_writeb(ctx, HDMI_RX_TMDS_CLK_EN_REG, 0x01);
> +	/* Enable Tx Clock Path & Equalizer */
> +	hdmi_writeb(ctx, HDMI_RX_TMDS_CH_EN_REG, 0x15);
> +	/* Power Up TMDS */
> +	mhl_tx_writeb(ctx, 0x08, 0x35);
> +	return sii9234_clear_error(ctx);
> +}
> +
> +static int sii9234_hdmi_init(struct sii9234 *ctx)
> +{
> +	/* Analog PLL Control bits 5:4 = 2b00 as per char. team. */
> +	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);

No magic value, please define macros for register bits.

> +	/* PLL Calrefsel */

All those comments won't be needed once you replace numerical values with 
explicitly named macros.

> +	hdmi_writeb(ctx, HDMI_RX_PLL_CALREFSEL_REG, 0x03);
> +	/* VCO Cal */
> +	hdmi_writeb(ctx, HDMI_RX_PLL_VCOCAL_REG, 0x20);
> +	/* Auto EQ */
> +	hdmi_writeb(ctx, HDMI_RX_EQ_DATA0_REG, 0x8A);
> +	/* Auto EQ */
> +	hdmi_writeb(ctx, HDMI_RX_EQ_DATA1_REG, 0x6A);
> +	/* Auto EQ */
> +	hdmi_writeb(ctx, HDMI_RX_EQ_DATA2_REG, 0xAA);
> +	/* Auto EQ */
> +	hdmi_writeb(ctx, HDMI_RX_EQ_DATA3_REG, 0xCA);
> +	/* Auto EQ */
> +	hdmi_writeb(ctx, HDMI_RX_EQ_DATA4_REG, 0xEA);
> +	/* Manual zone */
> +	hdmi_writeb(ctx, HDMI_RX_TMDS_ZONE_CTRL_REG, 0xA0);
> +	/* PLL Mode Value */
> +	hdmi_writeb(ctx, HDMI_RX_TMDS_MODE_CTRL_REG, 0x00);
> +	mhl_tx_writeb(ctx, MHL_TX_TMDS_CCTRL, 0x34);
> +	hdmi_writeb(ctx, 0x45, 0x44);
> +	/* Rx PLL BW ~ 4MHz */
> +	hdmi_writeb(ctx, 0x31, 0x0A);
> +	/* Analog PLL Control * bits 5:4 = 2b00 as per char. team. */
> +	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
> +
> +	return sii9234_clear_error(ctx);
> +}
> +
> +static int sii9234_mhl_tx_ctl_int(struct sii9234 *ctx)
> +{
> +	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0xD0);
> +	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL2_REG, 0xFC);
> +	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL4_REG, 0xEB);
> +	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL7_REG, 0x0C);
> +	return sii9234_clear_error(ctx);
> +}
> +
> +static int sii9234_reset(struct sii9234 *ctx)
> +{
> +	int ret;
> +
> +	sii9234_clear_error(ctx);
> +
> +	ret = sii9234_power_init(ctx);
> +	if (ret < 0)
> +		return ret;
> +	ret = sii9234_cbus_reset(ctx);
> +	if (ret < 0)
> +		return ret;
> +	ret = sii9234_hdmi_init(ctx);
> +	if (ret < 0)
> +		return ret;
> +	ret = sii9234_mhl_tx_ctl_int(ctx);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Enable HDCP Compliance safety */
> +	mhl_tx_writeb(ctx, 0x2B, 0x01);
> +	/* CBUS discovery cycle time for each drive and float = 150us */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0x04, 0x06);
> +	/* Clear bit 6 (reg_skip_rgnd) */
> +	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL2_REG, (1 << 7) /* Reserved */
> +		| 2 << ATT_THRESH_SHIFT | DEGLITCH_TIME_50MS);
> +	/* Changed from 66 to 65 for 94[1:0] = 01 = 5k reg_cbusmhl_pup_sel */
> +	/* 1.8V CBUS VTH & GND threshold */
> +	/*To meet CTS 3.3.7.2 spec */
> +	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
> +	/* set bit 2 and 3, which is Initiator Timeout */
> +	cbus_writebm(ctx, CBUS_LINK_CONTROL_2_REG, ~0, 0x0C);
> +	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL6_REG, 0xA0);
> +	/* RGND & single discovery attempt (RGND blocking) */
> +	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL6_REG, BLOCK_RGND_INT |
> +			       DVRFLT_SEL | SINGLE_ATT);
> +	/* Use VBUS path of discovery state machine */
> +	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL8_REG, 0);
> +	/* 0x92[3] sets the CBUS / ID switch */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
> +	/* To allow RGND engine to operate correctly.
> +	 * When moving the chip from D2 to D0 (power up, init regs)
> +	 * the values should be
> +	 * 94[1:0] = 01  reg_cbusmhl_pup_sel[1:0] should be set for 5k
> +	 * 93[7:6] = 10  reg_cbusdisc_pup_sel[1:0] should be
> +	 * set for 10k (default)
> +	 * 93[5:4] = 00  reg_cbusidle_pup_sel[1:0] = open (default)
> +	 */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
> +	/* change from CC to 8C to match 5K */
> +	/*To meet CTS 3.3.72 spec */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
> +	/* Configure the interrupt as active high */
> +	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x06);
> +
> +	msleep(25);
> +
> +	/* release usb_id switch */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0,  USB_ID_OVR);
> +	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL1_REG, 0x27);
> +
> +	ret = sii9234_clear_error(ctx);
> +	if (ret < 0)
> +		return ret;
> +	ret = sii9234_cbus_init(ctx);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Enable Auto soft reset on SCDT = 0 */
> +	mhl_tx_writeb(ctx, 0x05, 0x04);
> +	/* HDMI Transcode mode enable */
> +	mhl_tx_writeb(ctx, 0x0D, 0x1C);
> +	mhl_tx_writeb(ctx, MHL_TX_INTR4_ENABLE_REG,
> +			       RGND_READY_MASK | CBUS_LKOUT_MASK |
> +			       MHL_DISC_FAIL_MASK | MHL_EST_MASK);
> +	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG, 0x60);
> +
> +	/* this point is very importand before megsure RGND impedance */

s/megsure/measuring/

> +	force_usb_id_switch_open(ctx);
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, 0, 0xF0);
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL5_REG, 0, 0x03);
> +	release_usb_id_switch_open(ctx);
> +	/*end of this */

End of what ?

> +
> +	/* Force upstream HPD to 0 when not in MHL mode */
> +	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 1 << 5);
> +	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, ~0, 1 << 4);
> +
> +	return sii9234_clear_error(ctx);
> +}
> +
> +static int sii9234_goto_d3(struct sii9234 *ctx)
> +{
> +	int ret;
> +
> +	dev_dbg(ctx->dev, "sii9234: detection started d3\n");
> +
> +	ret = sii9234_reset(ctx);
> +	if (ret < 0)
> +		goto exit;
> +
> +	hdmi_writeb(ctx, 0x01, 0x03);
> +	tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
> +	/* I2C above is expected to fail because power goes down */
> +	sii9234_clear_error(ctx);
> +
> +	ctx->state = ST_D3;
> +
> +	return 0;
> + exit:
> +	dev_err(ctx->dev, "%s failed\n", __func__);
> +	return -1;
> +}
> +
> +#define sii9234_hw_on(sii9234) \
> +	regulator_enable((sii9234)->vcc_supply)
> +
> +static void sii9234_hw_off(struct sii9234 *ctx)
> +{
> +	gpiod_set_value(ctx->gpio_reset, 0);
> +	usleep_range(10000, 20000);
> +	gpiod_set_value(ctx->gpio_reset, 1);
> +	regulator_disable(ctx->vcc_supply);
> +	gpiod_set_value(ctx->gpio_reset, 0);
> +}
> +
> +static void sii9234_hw_reset(struct sii9234 *ctx)
> +{
> +	gpiod_set_value(ctx->gpio_reset, 0);
> +	usleep_range(10000, 20000);
> +	gpiod_set_value(ctx->gpio_reset, 1);
> +}
> +
> +static void sii9234_cable_in(struct sii9234 *ctx)
> +{
> +	int ret;
> +
> +	mutex_lock(&ctx->lock);
> +	if (ctx->state != ST_OFF)
> +		goto unlock;
> +	ret = sii9234_hw_on(ctx);
> +	if (ret < 0)
> +		goto unlock;
> +
> +	sii9234_hw_reset(ctx);
> +	sii9234_goto_d3(ctx);
> +	enable_irq(to_i2c_client(ctx->dev)->irq);

That looks like a hack. You should enable/disable IRQs in the SII9234, there 
should be no need to enable/disable them in the SoC IRQ controller. If there's 
really a need to do so, you should document why.

> +
> +unlock:
> +	mutex_unlock(&ctx->lock);
> +}
> +
> +static void sii9234_cable_out(struct sii9234 *ctx)
> +{
> +	mutex_lock(&ctx->lock);
> +
> +	if (ctx->state == ST_OFF)
> +		goto unlock;
> +
> +	disable_irq(to_i2c_client(ctx->dev)->irq);
> +	tpi_writeb(ctx, TPI_DPD_REG, 0);
> +	/*turn on&off hpd festure for only QCT HDMI */

Some of your comments start with a capitalized word, others don't. I'd 
capitalize them all for consistency.

> +	sii9234_hw_off(ctx);
> +
> +	ctx->state = ST_OFF;
> +
> +unlock:
> +	mutex_unlock(&ctx->lock);
> +}
> +
> +static enum sii9234_state sii9234_rgnd_ready_irq(struct sii9234 *ctx)
> +{
> +	int value;
> +
> +	if (ctx->state == ST_D3) {
> +		int ret;
> +
> +		dev_dbg(ctx->dev, "RGND_READY_INT\n");
> +		sii9234_hw_reset(ctx);
> +
> +		ret = sii9234_reset(ctx);
> +		if (ret < 0) {
> +			dev_err(ctx->dev, "sii9234_reset() failed\n");
> +			return ST_FAILURE;
> +		}
> +
> +		return ST_RGND_INIT;
> +	}
> +
> +	/* got interrupt in inappropriate state */
> +	if (ctx->state != ST_RGND_INIT)
> +		return ST_FAILURE;
> +
> +	value = mhl_tx_readb(ctx, MHL_TX_STAT2_REG);
> +	if (sii9234_clear_error(ctx))
> +		return ST_FAILURE;
> +
> +	if ((value & RGND_INTP_MASK) != RGND_INTP_1K) {
> +		dev_warn(ctx->dev, "RGND is not 1k\n");
> +		return ST_RGND_INIT;
> +	}
> +	dev_dbg(ctx->dev, "RGND 1K!!\n");
> +	/* After applying RGND patch, there is some issue
> +	 * about discovry failure
> +	 * This point is add to fix that problem
> +	 */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
> +	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, 0x05);
> +	if (sii9234_clear_error(ctx))
> +		return ST_FAILURE;
> +
> +	usleep_range(T_SRC_VBUS_CBUS_TO_STABLE * USEC_PER_MSEC,
> +		     T_SRC_VBUS_CBUS_TO_STABLE * USEC_PER_MSEC);
> +
> +	return ST_RGND_1K;
> +}
> +
> +static enum sii9234_state sii9234_mhl_established(struct sii9234 *ctx)
> +{
> +	dev_dbg(ctx->dev, "mhl est interrupt\n");
> +
> +	/* discovery override */
> +	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0x10);
> +	/* increase DDC translation layer timer (byte mode) */
> +	cbus_writeb(ctx, 0x07, 0x32);
> +	cbus_writebm(ctx, 0x44, ~0, 1 << 1);
> +	/* Keep the discovery enabled. Need RGND interrupt */
> +	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 1);
> +	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG,
> +	       RSEN_CHANGE_INT_MASK | HPD_CHANGE_INT_MASK);
> +
> +	if (sii9234_clear_error(ctx))
> +		return ST_FAILURE;
> +
> +	return ST_MHL_ESTABLISHED;
> +}
> +
> +static enum sii9234_state sii9234_hpd_change(struct sii9234 *ctx)
> +{
> +	int value;
> +
> +	value = cbus_readb(ctx, CBUS_MSC_REQ_ABORT_REASON_REG);
> +	if (sii9234_clear_error(ctx))
> +		return ST_FAILURE;
> +
> +	if (value & SET_HPD_DOWNSTREAM) {
> +		dev_info(ctx->dev, "HPD High\n");

You don't want to spam the kernel log every time a cable is plugged or 
unplugged. Use dev_dbg() if you want to keep those messages for debugging, or 
remove them altogether.

> +		/* Downstream HPD High, Enable TMDS */
> +		sii9234_tmds_control(ctx, true);
> +		/*turn on&off hpd festure for only QCT HDMI */

I'm not sure what the comment relates to as there's no line of code after it.

> +	} else {
> +		dev_info(ctx->dev, "HPD Low\n");
> +		/* Downstream HPD Low, Disable TMDS */
> +		sii9234_tmds_control(ctx, false);
> +	}
> +
> +	return ctx->state;
> +}
> +
> +static enum sii9234_state sii9234_rsen_change(struct sii9234 *ctx)
> +{
> +	int value;
> +
> +	/* work_around code to handle worng interrupt */

s/worng/wrong/

> +	if (ctx->state != ST_RGND_1K) {
> +		dev_err(ctx->dev, "RSEN_HIGH without RGND_1K\n");
> +		return ST_FAILURE;
> +	}
> +	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
> +	if (value < 0)
> +		return ST_FAILURE;
> +
> +	if (value & RSEN_STATUS) {
> +		dev_info(ctx->dev, "MHL cable connected.. RSEN High\n");
> +		return ST_RSEN_HIGH;
> +	}
> +	dev_info(ctx->dev, "RSEN lost\n");

Ditto, dev_dbg()

> +	/* Once RSEN loss is confirmed,we need to check
> +	 * based on cable status and chip power status,whether
> +	 * it is SINK Loss(HDMI cable not connected, TV Off)
> +	 * or MHL cable disconnection
> +	 * TODO: Define the below mhl_disconnection()
> +	 */
> +	msleep(T_SRC_RXSENSE_DEGLITCH);
> +	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
> +	if (value < 0)
> +		return ST_FAILURE;
> +	dev_dbg(ctx->dev, "sys_stat: %x\n", value);
> +
> +	if (value & RSEN_STATUS) {
> +		dev_info(ctx->dev, "RSEN recovery\n");
> +		return ST_RSEN_HIGH;
> +	}
> +	dev_info(ctx->dev, "RSEN Really LOW\n");

Same here, and everywhere else in the driver.

> +	/*To meet CTS 3.3.22.2 spec */
> +	sii9234_tmds_control(ctx, false);
> +	force_usb_id_switch_open(ctx);
> +	release_usb_id_switch_open(ctx);
> +
> +	return ST_FAILURE;
> +}
> +
> +static irqreturn_t sii9234_irq_thread(int irq, void *data)
> +{
> +	struct sii9234 *ctx = data;
> +	int intr1, intr4;
> +	int intr1_en, intr4_en;
> +	int cbus_intr1, cbus_intr2;
> +
> +	dev_dbg(ctx->dev, "%s\n", __func__);
> +
> +	msleep(30);

If this is really needed you should add a comment to explain why.

> +	mutex_lock(&ctx->lock);
> +
> +	intr1 = mhl_tx_readb(ctx, MHL_TX_INTR1_REG);
> +	intr4 = mhl_tx_readb(ctx, MHL_TX_INTR4_REG);
> +	intr1_en = mhl_tx_readb(ctx, MHL_TX_INTR1_ENABLE_REG);
> +	intr4_en = mhl_tx_readb(ctx, MHL_TX_INTR4_ENABLE_REG);
> +	cbus_intr1 = cbus_readb(ctx, CBUS_INT_STATUS_1_REG);
> +	cbus_intr2 = cbus_readb(ctx, CBUS_INT_STATUS_2_REG);
> +
> +	if (sii9234_clear_error(ctx))
> +		goto done;
> +
> +	dev_dbg(ctx->dev, "irq %02x/%02x %02x/%02x %02x/%02x\n",
> +		 intr1, intr1_en, intr4, intr4_en, cbus_intr1, cbus_intr2);
> +
> +	if (intr4 & RGND_READY_INT)
> +		ctx->state = sii9234_rgnd_ready_irq(ctx);
> +	if (intr1 & RSEN_CHANGE_INT)
> +		ctx->state = sii9234_rsen_change(ctx);
> +	if (intr4 & MHL_EST_INT)
> +		ctx->state = sii9234_mhl_established(ctx);
> +	if (intr1 & HPD_CHANGE_INT)
> +		ctx->state = sii9234_hpd_change(ctx);
> +	if (intr4 & CBUS_LKOUT_INT)
> +		ctx->state = ST_FAILURE;
> +	if (intr4 & MHL_DISC_FAIL_INT)
> +		ctx->state = ST_FAILURE_DISCOVERY;
> +
> + done:
> +	/* clean interrupt status and pending flags */
> +	mhl_tx_writeb(ctx, MHL_TX_INTR1_REG, intr1);
> +	mhl_tx_writeb(ctx, MHL_TX_INTR4_REG, intr4);
> +	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_0, 0xFF);
> +	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_1, 0xFF);
> +	cbus_writeb(ctx, CBUS_INT_STATUS_1_REG, cbus_intr1);
> +	cbus_writeb(ctx, CBUS_INT_STATUS_2_REG, cbus_intr2);
> +
> +	sii9234_clear_error(ctx);
> +
> +	if (ctx->state == ST_FAILURE) {
> +		dev_info(ctx->dev, "try to reset after failure\n");
> +		sii9234_hw_reset(ctx);
> +		sii9234_goto_d3(ctx);
> +	}
> +
> +	if (ctx->state == ST_FAILURE_DISCOVERY) {
> +		dev_err(ctx->dev, "discovery failed, no power for MHL?\n");
> +		tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
> +		ctx->state = ST_D3;
> +	}
> +
> +	mutex_unlock(&ctx->lock);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +
> +static int sii9234_init_resources(struct sii9234 *ctx,
> +	struct i2c_client *client)
> +{
> +	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
> +
> +	if (!ctx->dev->of_node) {
> +		dev_err(ctx->dev, "not DT device\n");
> +		return -ENODEV;
> +	}
> +
> +	ctx->gpio_reset = devm_gpiod_get(ctx->dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(ctx->gpio_reset)) {
> +		dev_err(ctx->dev, "failed to get reset gpio from DT\n");
> +		return PTR_ERR(ctx->gpio_reset);
> +	}
> +
> +	ctx->vcc_supply = devm_regulator_get(ctx->dev, "vcc");
> +	if (IS_ERR(ctx->vcc_supply)) {
> +		dev_err(ctx->dev, "failed to acquire regulator vcc\n");
> +		return PTR_ERR(ctx->vcc_supply);
> +	}
> +
> +	ctx->client[I2C_MHL] = client;
> +
> +	ctx->client[I2C_TPI] = i2c_new_dummy(adapter, 0x7A >> 1);

Please define macros for the secondary I2C addresses instead of using 
numerical values directly.

> +	if (!ctx->client[I2C_TPI]) {
> +		dev_err(ctx->dev, "failed to create TPI client\n");
> +		return -ENODEV;
> +	}
> +
> +	ctx->client[I2C_HDMI] = i2c_new_dummy(adapter, 0x92 >> 1);
> +	if (!ctx->client[I2C_HDMI]) {
> +		dev_err(ctx->dev, "failed to create HDMI RX client\n");
> +		goto fail_tpi;
> +	}
> +
> +	ctx->client[I2C_CBUS] = i2c_new_dummy(adapter, 0xC8 >> 1);
> +	if (!ctx->client[I2C_CBUS]) {
> +		dev_err(ctx->dev, "failed to create CBUS client\n");
> +		goto fail_hdmi;
> +	}
> +
> +	return 0;
> +
> +fail_hdmi:
> +	i2c_unregister_device(ctx->client[I2C_HDMI]);
> +fail_tpi:
> +	i2c_unregister_device(ctx->client[I2C_TPI]);
> +
> +	return -ENODEV;
> +}
> +
> +static void sii9234_deinit_resources(struct sii9234 *ctx)
> +{
> +	i2c_unregister_device(ctx->client[I2C_CBUS]);
> +	i2c_unregister_device(ctx->client[I2C_HDMI]);
> +	i2c_unregister_device(ctx->client[I2C_TPI]);
> +}
> +
> +static inline struct sii9234 *bridge_to_sii9234(struct drm_bridge *bridge)
> +{
> +	return container_of(bridge, struct sii9234, bridge);
> +}
> +
> +static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
> +					const struct drm_display_mode *mode)
> +{
> +	struct sii9234 *ctx = bridge_to_sii9234(bridge);
> +
> +	if (mode->clock > MHL1_MAX_CLK)
> +		return MODE_CLOCK_HIGH;
> +
> +	return MODE_OK;
> +}
> +
> +static const struct drm_bridge_funcs sii9234_bridge_funcs = {
> +	.mode_valid = sii9234_mode_valid,
> +};
> +
> +static int sii9234_mhl_tx_i2c_probe(struct i2c_client *client,
> +					      const struct i2c_device_id *id)
> +{
> +	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
> +	struct sii9234 *ctx;
> +	struct device *dev = &client->dev;
> +	int ret;
> +
> +	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx)
> +		return -ENOMEM;
> +
> +	ctx->dev = dev;
> +
> +	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
> +		dev_err(dev, "I2C adapter lacks SMBUS feature\n");
> +		return -EIO;
> +	}
> +
> +	mutex_init(&ctx->lock);
> +
> +	ret = sii9234_init_resources(ctx, client);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "failed to initialize sii9234 
resources\n");

No need for an error message here as all error paths in 
sii9234_init_resources() print a message already.

> +		return ret;
> +	}
> +	ret = sii9234_hw_on(ctx);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to enable power\n");
> +		goto err_resource;
> +	}
> +	sii9234_hw_reset(ctx);
> +
> +	if (!client->irq) {
> +		dev_err(dev, "no irq provided\n");
> +		return -EINVAL;

No need for clean up in the error path ? You can just move this check with the 
I2C functionality check to avoid the need to clean up.

> +	}
> +	irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
> +	ret = devm_request_threaded_irq(dev, client->irq, NULL,
> +					sii9234_irq_thread,
> +					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> +					"sii9234", ctx);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to install IRQ handler\n");
> +		return ret;
> +	}
> +
> +	i2c_set_clientdata(client, ctx);
> +
> +	ctx->bridge.funcs = &sii9234_bridge_funcs;
> +	ctx->bridge.of_node = dev->of_node;
> +	drm_bridge_add(&ctx->bridge);
> +
> +	sii9234_cable_in(ctx);
> +
> +	return 0;
> +
> +err_resource:
> +	sii9234_deinit_resources(ctx);
> +
> +	return ret;
> +}
> +
> +static int sii9234_mhl_tx_i2c_remove(struct i2c_client *client)
> +{
> +	struct sii9234 *ctx = i2c_get_clientdata(client);
> +
> +	sii9234_cable_out(ctx);
> +	drm_bridge_remove(&ctx->bridge);
> +	sii9234_deinit_resources(ctx);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id sii9234_dt_match[] = {
> +	{ .compatible = "sil,sii9234" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, sii9234_dt_match);
> +
> +static const struct i2c_device_id sii9234_id[] = {
> +	{ "SII9234", 0 },
> +	{ },
> +};
> +

Nitpicking, I'd move this blank line after MODULE_DEVICE_TABLE(i2c, 
sii9234_id);

> +MODULE_DEVICE_TABLE(i2c, sii9234_id);
> +static struct i2c_driver sii9234_driver = {
> +	.driver = {
> +		.name	= "sii9234",
> +		.owner	= THIS_MODULE,
> +		.of_match_table = of_match_ptr(sii9234_dt_match),

As the driver requires OF support the of_match_ptr() macro isn't needed.

> +	},
> +	.probe		= sii9234_mhl_tx_i2c_probe,
> +	.remove		= sii9234_mhl_tx_i2c_remove,
> +	.id_table = sii9234_id,
> +};
> +
> +module_i2c_driver(sii9234_driver);
> +MODULE_LICENSE("GPL");
kernel test robot Aug. 3, 2017, 7:36 p.m. UTC | #2
Hi Maciej,

[auto build test WARNING on drm/drm-next]
[also build test WARNING on v4.13-rc3 next-20170803]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Maciej-Purski/add-Silicon-Image-SiI9234-driver/20170803-200255
base:   git://people.freedesktop.org/~airlied/linux.git drm-next


coccinelle warnings: (new ones prefixed by >>)

>> drivers/gpu/drm/bridge/sii9234.c:1010:3-8: No need to set .owner here. The core will do it.

Please review and possibly fold the followup patch.

---
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https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
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Marek Szyprowski Aug. 4, 2017, 6:55 a.m. UTC | #3
Hi Laurent,

Thanks for your detailed comments. Maciej resurrected some orphaned code,
which is still useful today (Tomasz has left Samsung a few years ago).
I'm not sure we will be able to answer all your questions without deep
investigation, especially about the driver operation details, but we
will try.

On 2017-08-03 12:24, Laurent Pinchart wrote:
> Hi Maciej,
>
> Thank you for the patch.
>
> On Thursday 03 Aug 2017 09:45:22 Maciej Purski wrote:
>> SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
>> It is controlled via I2C bus. Its interaction with other
>> devices in video pipeline is performed mainly on HW level.
>> The only interaction it does on device driver level is
>> filtering-out unsupported video modes, it exposes drm_bridge
>> interface to perform this operation.
>>
>> This patch is based on the code refactored by Tomasz Stanislawski
>> <t.stanislaws@samsung.com>, which was initially developed by:
>> Adam Hampson <ahampson@sta.samsung.com>
>> Erik Gilling <konkers@android.com>
>> Shankar Bandal <shankar.b@samsung.com>
>> Dharam Kumar <dharam.kr@samsung.com>
>>
>> Signed-off-by: Maciej Purski <m.purski@samsung.com>
>> ---
>>   .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
>>   drivers/gpu/drm/bridge/Kconfig                     |    8 +
>>   drivers/gpu/drm/bridge/Makefile                    |    1 +
>>   drivers/gpu/drm/bridge/sii9234.c                   | 1019 +++++++++++++++++
>>   4 files changed, 1048 insertions(+)
>>   create mode 100644
>> Documentation/devicetree/bindings/display/bridge/sii9234.txt create mode
>> 100644 drivers/gpu/drm/bridge/sii9234.c
>>
>> diff --git a/Documentation/devicetree/bindings/display/bridge/sii9234.txt
>> b/Documentation/devicetree/bindings/display/bridge/sii9234.txt new file
>> mode 100644
>> index 0000000..2cdf286
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> DT reviewers might ask you to submit DT bindings as a separate patch.
>
>> @@ -0,0 +1,20 @@
>> +SiI9234 Mobile HD Link Transmitter
>> +
>> +Required properties:
>> +- compatible : "sil,sii9234".
>> +- reg : I2C address for TPI interface, use 0x39
>> +- vcc-supply : regulator that supplies the chip
> Is there a single power supply only ? Transceivers usually have at least one
> digital and one analog power supply.

Acording to the schematic there are four power supplies used for SII9234 
MHL chip in
Trats2 board: VSIL_1.2A, VSIL_1.2C, VCC_3.3V_MHL and VCC_1.8V_MHL. First 
two are
derived directly from VSIL_1.2 signal, which is modeled as a fixed 
regulator. The
latter two are derived directly from VBAT using some level converter, 
which is
controlled by the same GPIO pin as VSIL fixed regulator. Any idea how 
this should
be represented better in device tree instead of having single vcc-supply?

>
>> +- interrupts, interrupt-parent: interrupt specifier of INT pin
>> +- reset-gpios: gpio specifier of RESET pin
> Is this mandatory to connect the reset pin to the SoC ?

IMHO yes, the chip has to be reset during the initialization procedure 
and doesn't
work properly without reset.

> > [...] 

Best regards
Laurent Pinchart Aug. 10, 2017, 2:51 p.m. UTC | #4
Hi Marek,

On Friday 04 Aug 2017 08:55:55 Marek Szyprowski wrote:
> Hi Laurent,
> 
> Thanks for your detailed comments. Maciej resurrected some orphaned code,
> which is still useful today (Tomasz has left Samsung a few years ago).
> I'm not sure we will be able to answer all your questions without deep
> investigation, especially about the driver operation details, but we
> will try.

Thank you.

> On 2017-08-03 12:24, Laurent Pinchart wrote:
> > On Thursday 03 Aug 2017 09:45:22 Maciej Purski wrote:
> >> SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
> >> It is controlled via I2C bus. Its interaction with other
> >> devices in video pipeline is performed mainly on HW level.
> >> The only interaction it does on device driver level is
> >> filtering-out unsupported video modes, it exposes drm_bridge
> >> interface to perform this operation.
> >> 
> >> This patch is based on the code refactored by Tomasz Stanislawski
> >> <t.stanislaws@samsung.com>, which was initially developed by:
> >> Adam Hampson <ahampson@sta.samsung.com>
> >> Erik Gilling <konkers@android.com>
> >> Shankar Bandal <shankar.b@samsung.com>
> >> Dharam Kumar <dharam.kr@samsung.com>
> >> 
> >> Signed-off-by: Maciej Purski <m.purski@samsung.com>
> >> ---
> >> 
> >>   .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
> >>   drivers/gpu/drm/bridge/Kconfig                     |    8 +
> >>   drivers/gpu/drm/bridge/Makefile                    |    1 +
> >>   drivers/gpu/drm/bridge/sii9234.c                   | 1019 +++++++++++++
> >>   4 files changed, 1048 insertions(+)
> >>   create mode 100644
> >> 
> >> Documentation/devicetree/bindings/display/bridge/sii9234.txt create mode
> >> 100644 drivers/gpu/drm/bridge/sii9234.c
> >> 
> >> diff --git a/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> >> b/Documentation/devicetree/bindings/display/bridge/sii9234.txt new file
> >> mode 100644
> >> index 0000000..2cdf286
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> > 
> > DT reviewers might ask you to submit DT bindings as a separate patch.
> > 
> >> @@ -0,0 +1,20 @@
> >> +SiI9234 Mobile HD Link Transmitter
> >> +
> >> +Required properties:
> >> +- compatible : "sil,sii9234".
> >> +- reg : I2C address for TPI interface, use 0x39
> >> +- vcc-supply : regulator that supplies the chip
> > 
> > Is there a single power supply only ? Transceivers usually have at least
> > one digital and one analog power supply.
> 
> Acording to the schematic there are four power supplies used for SII9234
> MHL chip in Trats2 board: VSIL_1.2A, VSIL_1.2C, VCC_3.3V_MHL and
> VCC_1.8V_MHL. First two are derived directly from VSIL_1.2 signal, which is
> modeled as a fixed regulator. The latter two are derived directly from VBAT
> using some level converter, which is controlled by the same GPIO pin as VSIL
> fixed regulator. Any idea how this should be represented better in device
> tree instead of having single vcc-supply?

Without access to the documentation I can only guess, but it looks like 
VSIL_1.2A and VSIL_1.2C are supposed to be powered from the same power supply 
rail, possibly with different filters. I think they can be grouped together 
from a DT binding point of view. The last two supplies seem independent. We 
should thus probably model this as three separate supplies.

It would be useful to check in the SII9234 datasheet what power sequence the 
chip expects. Is there any chance you could find that document ?

> >> +- interrupts, interrupt-parent: interrupt specifier of INT pin
> >> +- reset-gpios: gpio specifier of RESET pin
> > 
> > Is this mandatory to connect the reset pin to the SoC ?
> 
> IMHO yes, the chip has to be reset during the initialization procedure
> and doesn't work properly without reset.

OK, I have no issue making the property mandatory then.
Marek Szyprowski Aug. 11, 2017, 7 a.m. UTC | #5
Hi Laurent,

On 2017-08-10 16:51, Laurent Pinchart wrote:
> Hi Marek,
>
> On Friday 04 Aug 2017 08:55:55 Marek Szyprowski wrote:
>> Hi Laurent,
>>
>> Thanks for your detailed comments. Maciej resurrected some orphaned code,
>> which is still useful today (Tomasz has left Samsung a few years ago).
>> I'm not sure we will be able to answer all your questions without deep
>> investigation, especially about the driver operation details, but we
>> will try.
> Thank you.
>
>> On 2017-08-03 12:24, Laurent Pinchart wrote:
>>> On Thursday 03 Aug 2017 09:45:22 Maciej Purski wrote:
>>>> SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
>>>> It is controlled via I2C bus. Its interaction with other
>>>> devices in video pipeline is performed mainly on HW level.
>>>> The only interaction it does on device driver level is
>>>> filtering-out unsupported video modes, it exposes drm_bridge
>>>> interface to perform this operation.
>>>>
>>>> This patch is based on the code refactored by Tomasz Stanislawski
>>>> <t.stanislaws@samsung.com>, which was initially developed by:
>>>> Adam Hampson <ahampson@sta.samsung.com>
>>>> Erik Gilling <konkers@android.com>
>>>> Shankar Bandal <shankar.b@samsung.com>
>>>> Dharam Kumar <dharam.kr@samsung.com>
>>>>
>>>> Signed-off-by: Maciej Purski <m.purski@samsung.com>
>>>> ---
>>>>
>>>>    .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
>>>>    drivers/gpu/drm/bridge/Kconfig                     |    8 +
>>>>    drivers/gpu/drm/bridge/Makefile                    |    1 +
>>>>    drivers/gpu/drm/bridge/sii9234.c                   | 1019 +++++++++++++
>>>>    4 files changed, 1048 insertions(+)
>>>>    create mode 100644
>>>>
>>>> Documentation/devicetree/bindings/display/bridge/sii9234.txt create mode
>>>> 100644 drivers/gpu/drm/bridge/sii9234.c
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/display/bridge/sii9234.txt
>>>> b/Documentation/devicetree/bindings/display/bridge/sii9234.txt new file
>>>> mode 100644
>>>> index 0000000..2cdf286
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
>>> DT reviewers might ask you to submit DT bindings as a separate patch.
>>>
>>>> @@ -0,0 +1,20 @@
>>>> +SiI9234 Mobile HD Link Transmitter
>>>> +
>>>> +Required properties:
>>>> +- compatible : "sil,sii9234".
>>>> +- reg : I2C address for TPI interface, use 0x39
>>>> +- vcc-supply : regulator that supplies the chip
>>> Is there a single power supply only ? Transceivers usually have at least
>>> one digital and one analog power supply.
>> Acording to the schematic there are four power supplies used for SII9234
>> MHL chip in Trats2 board: VSIL_1.2A, VSIL_1.2C, VCC_3.3V_MHL and
>> VCC_1.8V_MHL. First two are derived directly from VSIL_1.2 signal, which is
>> modeled as a fixed regulator. The latter two are derived directly from VBAT
>> using some level converter, which is controlled by the same GPIO pin as VSIL
>> fixed regulator. Any idea how this should be represented better in device
>> tree instead of having single vcc-supply?
> Without access to the documentation I can only guess, but it looks like
> VSIL_1.2A and VSIL_1.2C are supposed to be powered from the same power supply
> rail, possibly with different filters. I think they can be grouped together
> from a DT binding point of view. The last two supplies seem independent. We
> should thus probably model this as three separate supplies.

Okay, I see no problem adding support for all those three supplies, but 
I was
wondering how to model them in the device tree, because from the software
perspective ALL power supplies needed by this chip are enabled by a single
GPIO line switch.

I see 3 possible solutions:
1. Keep only single vcc supply for now and use fixed gpio regulator for it
as a provider. Add a comment that it fact it provides 3 different power 
signals.
2. Extend fixed gpio regulator driver and bindings so it will be possible to
have more than one fixed regulator controlled by the same gpio pin.
3. Model VCC_3.3V_MHL and VCC_1.8V_MHL providers as "vctrl-regulator" and
use this VSIL_1.2 as control voltage for them.

Which one do you prefer?

> It would be useful to check in the SII9234 datasheet what power sequence the
> chip expects. Is there any chance you could find that document ?

We have access only to the parts of the SII9234 documentation now and 
there is no
such information there.

>>>> +- interrupts, interrupt-parent: interrupt specifier of INT pin
>>>> +- reset-gpios: gpio specifier of RESET pin
>>> Is this mandatory to connect the reset pin to the SoC ?
>> IMHO yes, the chip has to be reset during the initialization procedure
>> and doesn't work properly without reset.
> OK, I have no issue making the property mandatory then.

Best regards
Laurent Pinchart Aug. 11, 2017, 8:59 a.m. UTC | #6
Hi Marek,

(CC'ing Mark Brown)

On Friday 11 Aug 2017 09:00:00 Marek Szyprowski wrote:
> On 2017-08-10 16:51, Laurent Pinchart wrote:
> > On Friday 04 Aug 2017 08:55:55 Marek Szyprowski wrote:
> >> Hi Laurent,
> >> 
> >> Thanks for your detailed comments. Maciej resurrected some orphaned code,
> >> which is still useful today (Tomasz has left Samsung a few years ago).
> >> I'm not sure we will be able to answer all your questions without deep
> >> investigation, especially about the driver operation details, but we
> >> will try.
> > 
> > Thank you.
> > 
> >> On 2017-08-03 12:24, Laurent Pinchart wrote:
> >>> On Thursday 03 Aug 2017 09:45:22 Maciej Purski wrote:
> >>>> SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
> >>>> It is controlled via I2C bus. Its interaction with other
> >>>> devices in video pipeline is performed mainly on HW level.
> >>>> The only interaction it does on device driver level is
> >>>> filtering-out unsupported video modes, it exposes drm_bridge
> >>>> interface to perform this operation.
> >>>> 
> >>>> This patch is based on the code refactored by Tomasz Stanislawski
> >>>> <t.stanislaws@samsung.com>, which was initially developed by:
> >>>> Adam Hampson <ahampson@sta.samsung.com>
> >>>> Erik Gilling <konkers@android.com>
> >>>> Shankar Bandal <shankar.b@samsung.com>
> >>>> Dharam Kumar <dharam.kr@samsung.com>
> >>>> 
> >>>> Signed-off-by: Maciej Purski <m.purski@samsung.com>
> >>>> ---
> >>>> 
> >>>>    .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
> >>>>    drivers/gpu/drm/bridge/Kconfig                     |    8 +
> >>>>    drivers/gpu/drm/bridge/Makefile                    |    1 +
> >>>>    drivers/gpu/drm/bridge/sii9234.c                   | 1019 ++++++++++
> >>>>    4 files changed, 1048 insertions(+)
> >>>>    create mode 100644
> >>>> 
> >>>> Documentation/devicetree/bindings/display/bridge/sii9234.txt create
> >>>> mode
> >>>> 100644 drivers/gpu/drm/bridge/sii9234.c
> >>>> 
> >>>> diff --git
> >>>> a/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> >>>> b/Documentation/devicetree/bindings/display/bridge/sii9234.txt new file
> >>>> mode 100644
> >>>> index 0000000..2cdf286
> >>>> --- /dev/null
> >>>> +++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> >>> 
> >>> DT reviewers might ask you to submit DT bindings as a separate patch.
> >>> 
> >>>> @@ -0,0 +1,20 @@
> >>>> +SiI9234 Mobile HD Link Transmitter
> >>>> +
> >>>> +Required properties:
> >>>> +- compatible : "sil,sii9234".
> >>>> +- reg : I2C address for TPI interface, use 0x39
> >>>> +- vcc-supply : regulator that supplies the chip
> >>> 
> >>> Is there a single power supply only ? Transceivers usually have at least
> >>> one digital and one analog power supply.
> >> 
> >> Acording to the schematic there are four power supplies used for SII9234
> >> MHL chip in Trats2 board: VSIL_1.2A, VSIL_1.2C, VCC_3.3V_MHL and
> >> VCC_1.8V_MHL. First two are derived directly from VSIL_1.2 signal, which
> >> is modeled as a fixed regulator. The latter two are derived directly from
> >> VBAT using some level converter, which is controlled by the same GPIO pin
> >> as VSIL fixed regulator. Any idea how this should be represented better
> >> in device tree instead of having single vcc-supply?
> > 
> > Without access to the documentation I can only guess, but it looks like
> > VSIL_1.2A and VSIL_1.2C are supposed to be powered from the same power
> > supply rail, possibly with different filters. I think they can be grouped
> > together from a DT binding point of view. The last two supplies seem
> > independent. We should thus probably model this as three separate
> > supplies.
> 
> Okay, I see no problem adding support for all those three supplies, but
> I was wondering how to model them in the device tree, because from the
> software perspective ALL power supplies needed by this chip are enabled by a
> single GPIO line switch.
> 
> I see 3 possible solutions:
> 1. Keep only single vcc supply for now and use fixed gpio regulator for it
> as a provider. Add a comment that it fact it provides 3 different power
> signals.
> 2. Extend fixed gpio regulator driver and bindings so it will be possible to
> have more than one fixed regulator controlled by the same gpio pin.
> 3. Model VCC_3.3V_MHL and VCC_1.8V_MHL providers as "vctrl-regulator" and
> use this VSIL_1.2 as control voltage for them.
> 
> Which one do you prefer?

2 would be best I think, but that's more work. Mark, what do you think ?

> > It would be useful to check in the SII9234 datasheet what power sequence
> > the chip expects. Is there any chance you could find that document ?
> 
> We have access only to the parts of the SII9234 documentation now and
> there is no
> such information there.
> 
> >>>> +- interrupts, interrupt-parent: interrupt specifier of INT pin
> >>>> +- reset-gpios: gpio specifier of RESET pin
> >>> 
> >>> Is this mandatory to connect the reset pin to the SoC ?
> >> 
> >> IMHO yes, the chip has to be reset during the initialization procedure
> >> and doesn't work properly without reset.
> > 
> > OK, I have no issue making the property mandatory then.
> 
> Best regards
Laurent Pinchart Aug. 11, 2017, 9 a.m. UTC | #7
Hi Marek,

(now CC'ing Mark Brown with his correct e-mail address)

On Friday 11 Aug 2017 09:00:00 Marek Szyprowski wrote:
> On 2017-08-10 16:51, Laurent Pinchart wrote:
> > On Friday 04 Aug 2017 08:55:55 Marek Szyprowski wrote:
> >> Hi Laurent,
> >> 
> >> Thanks for your detailed comments. Maciej resurrected some orphaned code,
> >> which is still useful today (Tomasz has left Samsung a few years ago).
> >> I'm not sure we will be able to answer all your questions without deep
> >> investigation, especially about the driver operation details, but we
> >> will try.
> > 
> > Thank you.
> > 
> >> On 2017-08-03 12:24, Laurent Pinchart wrote:
> >>> On Thursday 03 Aug 2017 09:45:22 Maciej Purski wrote:
> >>>> SiI9234 transmitter converts eTMDS/HDMI signal to MHL 1.0.
> >>>> It is controlled via I2C bus. Its interaction with other
> >>>> devices in video pipeline is performed mainly on HW level.
> >>>> The only interaction it does on device driver level is
> >>>> filtering-out unsupported video modes, it exposes drm_bridge
> >>>> interface to perform this operation.
> >>>> 
> >>>> This patch is based on the code refactored by Tomasz Stanislawski
> >>>> <t.stanislaws@samsung.com>, which was initially developed by:
> >>>> Adam Hampson <ahampson@sta.samsung.com>
> >>>> Erik Gilling <konkers@android.com>
> >>>> Shankar Bandal <shankar.b@samsung.com>
> >>>> Dharam Kumar <dharam.kr@samsung.com>
> >>>> 
> >>>> Signed-off-by: Maciej Purski <m.purski@samsung.com>
> >>>> ---
> >>>> 
> >>>>    .../devicetree/bindings/display/bridge/sii9234.txt |   20 +
> >>>>    drivers/gpu/drm/bridge/Kconfig                     |    8 +
> >>>>    drivers/gpu/drm/bridge/Makefile                    |    1 +
> >>>>    drivers/gpu/drm/bridge/sii9234.c                   | 1019 ++++++++++
> >>>>    4 files changed, 1048 insertions(+)
> >>>>    create mode 100644
> >>>> 
> >>>> Documentation/devicetree/bindings/display/bridge/sii9234.txt create
> >>>> mode
> >>>> 100644 drivers/gpu/drm/bridge/sii9234.c
> >>>> 
> >>>> diff --git
> >>>> a/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> >>>> b/Documentation/devicetree/bindings/display/bridge/sii9234.txt new file
> >>>> mode 100644
> >>>> index 0000000..2cdf286
> >>>> --- /dev/null
> >>>> +++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
> >>> 
> >>> DT reviewers might ask you to submit DT bindings as a separate patch.
> >>> 
> >>>> @@ -0,0 +1,20 @@
> >>>> +SiI9234 Mobile HD Link Transmitter
> >>>> +
> >>>> +Required properties:
> >>>> +- compatible : "sil,sii9234".
> >>>> +- reg : I2C address for TPI interface, use 0x39
> >>>> +- vcc-supply : regulator that supplies the chip
> >>> 
> >>> Is there a single power supply only ? Transceivers usually have at least
> >>> one digital and one analog power supply.
> >> 
> >> Acording to the schematic there are four power supplies used for SII9234
> >> MHL chip in Trats2 board: VSIL_1.2A, VSIL_1.2C, VCC_3.3V_MHL and
> >> VCC_1.8V_MHL. First two are derived directly from VSIL_1.2 signal, which
> >> is modeled as a fixed regulator. The latter two are derived directly from
> >> VBAT using some level converter, which is controlled by the same GPIO pin
> >> as VSIL fixed regulator. Any idea how this should be represented better
> >> in device tree instead of having single vcc-supply?
> > 
> > Without access to the documentation I can only guess, but it looks like
> > VSIL_1.2A and VSIL_1.2C are supposed to be powered from the same power
> > supply rail, possibly with different filters. I think they can be grouped
> > together from a DT binding point of view. The last two supplies seem
> > independent. We should thus probably model this as three separate
> > supplies.
> 
> Okay, I see no problem adding support for all those three supplies, but
> I was wondering how to model them in the device tree, because from the
> software perspective ALL power supplies needed by this chip are enabled by a
> single GPIO line switch.
> 
> I see 3 possible solutions:
> 1. Keep only single vcc supply for now and use fixed gpio regulator for it
> as a provider. Add a comment that it fact it provides 3 different power
> signals.
> 2. Extend fixed gpio regulator driver and bindings so it will be possible to
> have more than one fixed regulator controlled by the same gpio pin.
> 3. Model VCC_3.3V_MHL and VCC_1.8V_MHL providers as "vctrl-regulator" and
> use this VSIL_1.2 as control voltage for them.
> 
> Which one do you prefer?

2 would be best I think, but that's more work. Mark, what do you think ?

> > It would be useful to check in the SII9234 datasheet what power sequence
> > the chip expects. Is there any chance you could find that document ?
> 
> We have access only to the parts of the SII9234 documentation now and
> there is no
> such information there.
> 
> >>>> +- interrupts, interrupt-parent: interrupt specifier of INT pin
> >>>> +- reset-gpios: gpio specifier of RESET pin
> >>> 
> >>> Is this mandatory to connect the reset pin to the SoC ?
> >> 
> >> IMHO yes, the chip has to be reset during the initialization procedure
> >> and doesn't work properly without reset.
> > 
> > OK, I have no issue making the property mandatory then.
> 
> Best regards
kernel test robot Aug. 12, 2017, 10:43 p.m. UTC | #8
Hi Maciej,

[auto build test ERROR on drm/drm-next]
[also build test ERROR on v4.13-rc4 next-20170811]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Maciej-Purski/add-Silicon-Image-SiI9234-driver/20170803-200255
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
config: i386-randconfig-h0-08130402 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All errors (new ones prefixed by >>):

   drivers/gpu//drm/bridge/sii9234.c: In function 'sii9234_mode_valid':
   drivers/gpu//drm/bridge/sii9234.c:909:18: warning: unused variable 'ctx' [-Wunused-variable]
     struct sii9234 *ctx = bridge_to_sii9234(bridge);
                     ^~~
   drivers/gpu//drm/bridge/sii9234.c: In function 'sii9234_mhl_tx_i2c_probe':
>> drivers/gpu//drm/bridge/sii9234.c:971:13: error: 'struct drm_bridge' has no member named 'of_node'
     ctx->bridge.of_node = dev->of_node;
                ^
   In file included from include/uapi/linux/stddef.h:1:0,
                    from include/linux/stddef.h:4,
                    from include/uapi/linux/posix_types.h:4,
                    from include/uapi/linux/types.h:13,
                    from include/linux/types.h:5,
                    from include/drm/bridge/mhl.h:18,
                    from drivers/gpu//drm/bridge/sii9234.c:26:
   drivers/gpu//drm/bridge/sii9234.c: At top level:
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'strcpy' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:390:2: note: in expansion of macro 'if'
     if (p_size == (size_t)-1 && q_size == (size_t)-1)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'kmemdup' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:380:2: note: in expansion of macro 'if'
     if (p_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'kmemdup' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:378:2: note: in expansion of macro 'if'
     if (__builtin_constant_p(size) && p_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr_inv' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:369:2: note: in expansion of macro 'if'
     if (p_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr_inv' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:367:2: note: in expansion of macro 'if'
     if (__builtin_constant_p(size) && p_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:358:2: note: in expansion of macro 'if'
     if (p_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memchr' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:356:2: note: in expansion of macro 'if'
     if (__builtin_constant_p(size) && p_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memcmp' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:348:2: note: in expansion of macro 'if'
     if (p_size < size || q_size < size)
     ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memcmp' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:345:3: note: in expansion of macro 'if'
      if (q_size < size)
      ^~
   include/linux/compiler.h:162:4: warning: '______f' is static but declared in inline function 'memcmp' which is not static
       ______f = {     \
       ^
   include/linux/compiler.h:154:23: note: in expansion of macro '__trace_if'
    #define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
                          ^~~~~~~~~~
   include/linux/string.h:343:3: note: in expansion of macro 'if'
      if (p_size < size)
      ^~

vim +971 drivers/gpu//drm/bridge/sii9234.c

   905	
   906	static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
   907						const struct drm_display_mode *mode)
   908	{
 > 909		struct sii9234 *ctx = bridge_to_sii9234(bridge);
   910	
   911		if (mode->clock > MHL1_MAX_CLK)
   912			return MODE_CLOCK_HIGH;
   913	
   914		return MODE_OK;
   915	}
   916	
   917	static const struct drm_bridge_funcs sii9234_bridge_funcs = {
   918		.mode_valid = sii9234_mode_valid,
   919	};
   920	
   921	static int sii9234_mhl_tx_i2c_probe(struct i2c_client *client,
   922						      const struct i2c_device_id *id)
   923	{
   924		struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
   925		struct sii9234 *ctx;
   926		struct device *dev = &client->dev;
   927		int ret;
   928	
   929		ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
   930		if (!ctx)
   931			return -ENOMEM;
   932	
   933		ctx->dev = dev;
   934	
   935		if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
   936			dev_err(dev, "I2C adapter lacks SMBUS feature\n");
   937			return -EIO;
   938		}
   939	
   940		mutex_init(&ctx->lock);
   941	
   942		ret = sii9234_init_resources(ctx, client);
   943		if (ret < 0) {
   944			dev_err(&client->dev, "failed to initialize sii9234 resources\n");
   945			return ret;
   946		}
   947		ret = sii9234_hw_on(ctx);
   948		if (ret) {
   949			dev_err(&client->dev, "failed to enable power\n");
   950			goto err_resource;
   951		}
   952		sii9234_hw_reset(ctx);
   953	
   954		if (!client->irq) {
   955			dev_err(dev, "no irq provided\n");
   956			return -EINVAL;
   957		}
   958		irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
   959		ret = devm_request_threaded_irq(dev, client->irq, NULL,
   960						sii9234_irq_thread,
   961						IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
   962						"sii9234", ctx);
   963		if (ret < 0) {
   964			dev_err(dev, "failed to install IRQ handler\n");
   965			return ret;
   966		}
   967	
   968		i2c_set_clientdata(client, ctx);
   969	
   970		ctx->bridge.funcs = &sii9234_bridge_funcs;
 > 971		ctx->bridge.of_node = dev->of_node;
   972		drm_bridge_add(&ctx->bridge);
   973	
   974		sii9234_cable_in(ctx);
   975	
   976		return 0;
   977	
   978	err_resource:
   979		sii9234_deinit_resources(ctx);
   980	
   981		return ret;
   982	}
   983	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Mark Brown Aug. 14, 2017, 4:35 p.m. UTC | #9
On Fri, Aug 11, 2017 at 12:00:43PM +0300, Laurent Pinchart wrote:

> (now CC'ing Mark Brown with his correct e-mail address)

This is a *lot* of quoted discussion...

> > Okay, I see no problem adding support for all those three supplies, but
> > I was wondering how to model them in the device tree, because from the
> > software perspective ALL power supplies needed by this chip are enabled by a
> > single GPIO line switch.

> > I see 3 possible solutions:
> > 1. Keep only single vcc supply for now and use fixed gpio regulator for it
> > as a provider. Add a comment that it fact it provides 3 different power
> > signals.
> > 2. Extend fixed gpio regulator driver and bindings so it will be possible to
> > have more than one fixed regulator controlled by the same gpio pin.
> > 3. Model VCC_3.3V_MHL and VCC_1.8V_MHL providers as "vctrl-regulator" and
> > use this VSIL_1.2 as control voltage for them.

> > Which one do you prefer?

> 2 would be best I think, but that's more work. Mark, what do you think ?

Just model them all individually and let the regulator framework sort it
out.  It's got the concept of shared GPIO enables already so you should
be able to just describe the system directly and the framework will
figure things out, and even if it didn't there should be no need to
change any of the bindings here.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/display/bridge/sii9234.txt b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
new file mode 100644
index 0000000..2cdf286
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/sii9234.txt
@@ -0,0 +1,20 @@ 
+SiI9234 Mobile HD Link Transmitter
+
+Required properties:
+- compatible : "sil,sii9234".
+- reg : I2C address for TPI interface, use 0x39
+- vcc-supply : regulator that supplies the chip
+- interrupts, interrupt-parent: interrupt specifier of INT pin
+- reset-gpios: gpio specifier of RESET pin
+
+Additional compatible properties are also allowed.
+
+Example:
+	sii9234@39 {
+		compatible = "sil,sii9234";
+		reg = <0x39>;
+		vcc-supply = <&vsil>;
+		reset-gpios = <&gpf3 4 GPIO_ACTIVE_HIGH>;
+		interrupt-parent = <&gpf3>;
+		interrupts = <5 IRQ_TYPE_LEVEL_HIGH>;
+	};
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index adf9ae0..f5784e5 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -100,6 +100,14 @@  config DRM_TI_TFP410
 	---help---
 	  Texas Instruments TFP410 DVI/HDMI Transmitter driver
 
+config DRM_SII9234
+	tristate "Silicon Image SII9234 Driver"
+	depends on I2C
+	help
+	  Say Y here if you want support for the MHL interface.
+	  It is an I2C driver, that detects connection of MHL bridge
+	  and starts encapsulation of HDMI signal.
+
 source "drivers/gpu/drm/bridge/analogix/Kconfig"
 
 source "drivers/gpu/drm/bridge/adv7511/Kconfig"
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index defcf1e..e3d5eb0 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -6,6 +6,7 @@  obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
 obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
 obj-$(CONFIG_DRM_SIL_SII8620) += sil-sii8620.o
 obj-$(CONFIG_DRM_SII902X) += sii902x.o
+obj-$(CONFIG_DRM_SII9234) += sii9234.o
 obj-$(CONFIG_DRM_TOSHIBA_TC358767) += tc358767.o
 obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
 obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
diff --git a/drivers/gpu/drm/bridge/sii9234.c b/drivers/gpu/drm/bridge/sii9234.c
new file mode 100644
index 0000000..9c436e7
--- /dev/null
+++ b/drivers/gpu/drm/bridge/sii9234.c
@@ -0,0 +1,1019 @@ 
+/*
+ * Copyright (C) 2014 Samsung Electronics
+ *
+ * Author: Tomasz Stanislawski <t.stanislaws@samsung.com>
+ *
+ * Based on sii9234 driver created by:
+ *    Adam Hampson <ahampson@sta.samsung.com>
+ *    Erik Gilling <konkers@android.com>
+ *    Shankar Bandal <shankar.b@samsung.com>
+ *    Dharam Kumar <dharam.kr@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program
+ *
+ */
+#include <drm/bridge/mhl.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_edid.h>
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/file.h>
+#include <linux/uaccess.h>
+#include <linux/proc_fs.h>
+#include <linux/extcon.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/extcon.h>
+#include <linux/regulator/machine.h>
+
+/* MHL Tx registers and bits */
+#define MHL_TX_SRST                     0x05
+#define MHL_TX_SYSSTAT_REG              0x09
+#define MHL_TX_INTR1_REG                0x71
+#define MHL_TX_INTR4_REG                0x74
+#define MHL_TX_INTR1_ENABLE_REG         0x75
+#define MHL_TX_INTR4_ENABLE_REG         0x78
+#define MHL_TX_INT_CTRL_REG             0x79
+#define MHL_TX_TMDS_CCTRL               0x80
+#define MHL_TX_DISC_CTRL1_REG           0x90
+#define MHL_TX_DISC_CTRL2_REG           0x91
+#define MHL_TX_DISC_CTRL3_REG           0x92
+#define MHL_TX_DISC_CTRL4_REG		0x93
+#define MHL_TX_DISC_CTRL5_REG           0x94
+#define MHL_TX_DISC_CTRL6_REG           0x95
+#define MHL_TX_DISC_CTRL7_REG           0x96
+#define MHL_TX_DISC_CTRL8_REG		0x97
+#define MHL_TX_STAT2_REG                0x99
+#define MHL_TX_MHLTX_CTL1_REG           0xA0
+#define MHL_TX_MHLTX_CTL2_REG           0xA1
+#define MHL_TX_MHLTX_CTL4_REG           0xA3
+#define MHL_TX_MHLTX_CTL6_REG           0xA5
+#define MHL_TX_MHLTX_CTL7_REG           0xA6
+
+
+#define RSEN_STATUS			BIT(2)
+#define HPD_CHANGE_INT			BIT(6)
+#define RSEN_CHANGE_INT			BIT(5)
+#define RGND_READY_INT			BIT(6)
+#define VBUS_LOW_INT			BIT(5)
+#define CBUS_LKOUT_INT			BIT(4)
+#define MHL_DISC_FAIL_INT		BIT(3)
+#define MHL_EST_INT			BIT(2)
+#define HPD_CHANGE_INT_MASK		BIT(6)
+#define RSEN_CHANGE_INT_MASK		BIT(5)
+
+#define RGND_READY_MASK			BIT(6)
+#define CBUS_LKOUT_MASK			BIT(4)
+#define MHL_DISC_FAIL_MASK		BIT(3)
+#define MHL_EST_MASK			BIT(2)
+
+#define SKIP_GND			BIT(6)
+
+#define ATT_THRESH_SHIFT		0x04
+#define ATT_THRESH_MASK			(0x03 << ATT_THRESH_SHIFT)
+#define USB_D_OEN			BIT(3)
+#define DEGLITCH_TIME_MASK		0x07
+#define DEGLITCH_TIME_2MS		0
+#define DEGLITCH_TIME_4MS		1
+#define DEGLITCH_TIME_8MS		2
+#define DEGLITCH_TIME_16MS		3
+#define DEGLITCH_TIME_40MS		4
+#define DEGLITCH_TIME_50MS		5
+#define DEGLITCH_TIME_60MS		6
+#define DEGLITCH_TIME_128MS		7
+
+#define USB_D_OVR			BIT(7)
+#define USB_ID_OVR			BIT(6)
+#define DVRFLT_SEL			BIT(5)
+#define BLOCK_RGND_INT			BIT(4)
+#define SKIP_DEG			BIT(3)
+#define CI2CA_POL			BIT(2)
+#define CI2CA_WKUP			BIT(1)
+#define SINGLE_ATT			BIT(0)
+
+#define USB_D_ODN			BIT(5)
+#define VBUS_CHECK			BIT(2)
+#define RGND_INTP_MASK			0x03
+#define RGND_INTP_OPEN			0
+#define RGND_INTP_2K			1
+#define RGND_INTP_1K			2
+#define RGND_INTP_SHORT			3
+
+
+/* HDMI registers */
+#define HDMI_RX_TMDS0_CCTRL1_REG	0x10
+#define HDMI_RX_TMDS_CLK_EN_REG		0x11
+#define HDMI_RX_TMDS_CH_EN_REG		0x12
+#define HDMI_RX_PLL_CALREFSEL_REG	0x17
+#define HDMI_RX_PLL_VCOCAL_REG		0x1A
+#define HDMI_RX_EQ_DATA0_REG		0x22
+#define HDMI_RX_EQ_DATA1_REG		0x23
+#define HDMI_RX_EQ_DATA2_REG		0x24
+#define HDMI_RX_EQ_DATA3_REG		0x25
+#define HDMI_RX_EQ_DATA4_REG		0x26
+#define HDMI_RX_TMDS_ZONE_CTRL_REG	0x4C
+#define HDMI_RX_TMDS_MODE_CTRL_REG	0x4D
+
+/* CBUS registers */
+#define CBUS_INT_STATUS_1_REG		0x08
+#define CBUS_INTR1_ENABLE_REG		0x09
+#define CBUS_MSC_REQ_ABORT_REASON_REG	0x0D
+#define SET_HPD_DOWNSTREAM		(1<<6)
+#define CBUS_INT_STATUS_2_REG		0x1E
+#define CBUS_INTR2_ENABLE_REG		0x1F
+#define CBUS_LINK_CONTROL_2_REG		0x31
+#define CBUS_DEVCAP_DEV_STATE		0x80
+#define CBUS_DEVCAP_MHL_VERSION		0x81
+#define CBUS_DEVCAP_DEV_CAT		0x82
+#define CBUS_DEVCAP_ADOPTER_ID_H	0x83
+#define CBUS_DEVCAP_ADOPTER_ID_L	0x84
+#define CBUS_DEVCAP_VID_LINK_MODE	0x85
+#define CBUS_DEVCAP_AUD_LINK_MODE	0x86
+#define CBUS_DEVCAP_VIDEO_TYPE		0x87
+#define CBUS_DEVCAP_LOG_DEV_MAP		0x88
+#define CBUS_DEVCAP_BANDWIDTH		0x89
+#define CBUS_DEVCAP_DEV_FEATURE_FLAG	0x8A
+#define CBUS_DEVCAP_DEVICE_ID_H		0x8B
+#define CBUS_DEVCAP_DEVICE_ID_L		0x8C
+#define CBUS_DEVCAP_SCRATCHPAD_SIZE	0x8D
+#define CBUS_DEVCAP_INT_STAT_SIZE	0x8E
+#define CBUS_DEVCAP_RESERVED		0x8F
+#define CBUS_MHL_STATUS_REG_0		0xB0
+#define CBUS_MHL_STATUS_REG_1		0xB1
+
+/* TPI registers */
+#define TPI_DPD_REG			0x3D
+
+/* timeouts */
+#define T_SRC_VBUS_CBUS_TO_STABLE	200
+#define T_SRC_CBUS_FLOAT		100
+#define T_SRC_CBUS_DEGLITCH		2
+#define T_SRC_RXSENSE_DEGLITCH		110
+#define MHL1_MAX_CLK			75000
+
+enum sii9234_state {
+	ST_OFF,
+	ST_D3,
+	ST_RGND_INIT,
+	ST_RGND_1K,
+	ST_RSEN_HIGH,
+	ST_MHL_ESTABLISHED,
+	ST_FAILURE_DISCOVERY,
+	ST_FAILURE,
+};
+
+struct sii9234 {
+	struct i2c_client *client[4];
+	struct drm_bridge bridge;
+	struct device *dev;
+	struct gpio_desc *gpio_reset;
+	int i2c_error;
+	struct regulator *vcc_supply;
+
+	enum sii9234_state state;
+	struct mutex lock;
+};
+
+enum sii9234_client_id {
+	I2C_MHL,
+	I2C_TPI,
+	I2C_HDMI,
+	I2C_CBUS,
+};
+
+static char *sii9234_client_name[] = {
+	[I2C_MHL] = "MHL",
+	[I2C_TPI] = "TPI",
+	[I2C_HDMI] = "HDMI",
+	[I2C_CBUS] = "CBUS",
+};
+
+static int sii9234_writeb(struct sii9234 *ctx, int id, int offset,
+			    int value)
+{
+	int ret;
+	struct i2c_client *client = ctx->client[id];
+
+	if (ctx->i2c_error)
+		return ctx->i2c_error;
+
+	ret = i2c_smbus_write_byte_data(client, offset, value);
+	if (ret < 0)
+		dev_err(ctx->dev, "writeb: %4s[0x%02x] <- 0x%02x\n",
+			sii9234_client_name[id], offset, value);
+	ctx->i2c_error = ret;
+	return ret;
+}
+
+static int sii9234_writebm(struct sii9234 *ctx, int id, int offset,
+			    int value, int mask)
+{
+	int ret;
+	struct i2c_client *client = ctx->client[id];
+
+	if (ctx->i2c_error)
+		return ctx->i2c_error;
+
+	ret = i2c_smbus_write_byte(client, offset);
+	if (ret < 0) {
+		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
+			sii9234_client_name[id], offset, value);
+		ctx->i2c_error = ret;
+		return ret;
+	}
+
+	ret = i2c_smbus_read_byte(client);
+	if (ret < 0) {
+		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
+			sii9234_client_name[id], offset, value);
+		ctx->i2c_error = ret;
+		return ret;
+	}
+
+	value = (value & mask) | (ret & ~mask);
+
+	ret = i2c_smbus_write_byte_data(client, offset, value);
+	if (ret < 0) {
+		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
+			sii9234_client_name[id], offset, value);
+		ctx->i2c_error = ret;
+	}
+	return ret;
+}
+
+static int sii9234_readb(struct sii9234 *ctx, int id, int offset)
+{
+	int ret;
+	struct i2c_client *client = ctx->client[id];
+
+	if (ctx->i2c_error)
+		return ctx->i2c_error;
+
+	ret = i2c_smbus_write_byte(client, offset);
+	if (ret < 0) {
+		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
+			sii9234_client_name[id], offset);
+		ctx->i2c_error = ret;
+		return ret;
+	}
+
+	ret = i2c_smbus_read_byte(client);
+	if (ret < 0) {
+		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
+			sii9234_client_name[id], offset);
+		ctx->i2c_error = ret;
+	}
+
+	return ret;
+}
+
+static int sii9234_clear_error(struct sii9234 *ctx)
+{
+	int ret = ctx->i2c_error;
+
+	ctx->i2c_error = 0;
+	return ret;
+}
+
+#define mhl_tx_writeb(sii9234, offset, value) \
+	sii9234_writeb(sii9234, I2C_MHL, offset, value)
+#define mhl_tx_writebm(sii9234, offset, value, mask) \
+	sii9234_writebm(sii9234, I2C_MHL, offset, value, mask)
+#define mhl_tx_readb(sii9234, offset) \
+	sii9234_readb(sii9234, I2C_MHL, offset)
+#define cbus_writeb(sii9234, offset, value) \
+	sii9234_writeb(sii9234, I2C_CBUS, offset, value)
+#define cbus_writebm(sii9234, offset, value, mask) \
+	sii9234_writebm(sii9234, I2C_CBUS, offset, value, mask)
+#define cbus_readb(sii9234, offset) \
+	sii9234_readb(sii9234, I2C_CBUS, offset)
+#define hdmi_writeb(sii9234, offset, value) \
+	sii9234_writeb(sii9234, I2C_HDMI, offset, value)
+#define hdmi_writebm(sii9234, offset, value, mask) \
+	sii9234_writebm(sii9234, I2C_HDMI, offset, value, mask)
+#define hdmi_readb(sii9234, offset) \
+	sii9234_readb(sii9234, I2C_HDMI, offset)
+#define tpi_writeb(sii9234, offset, value) \
+	sii9234_writeb(sii9234, I2C_TPI, offset, value)
+#define tpi_writebm(sii9234, offset, value, mask) \
+	sii9234_writebm(sii9234, I2C_TPI, offset, value, mask)
+#define tpi_readb(sii9234, offset) \
+	sii9234_readb(sii9234, I2C_TPI, offset)
+
+static u8 sii9234_tmds_control(struct sii9234 *ctx, bool enable)
+{
+	mhl_tx_writebm(ctx, MHL_TX_TMDS_CCTRL, enable ? ~0 : 0, 0x10);
+	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, enable ? ~0 : 0, 0x30);
+	return sii9234_clear_error(ctx);
+}
+
+static int sii9234_cbus_reset(struct sii9234 *ctx)
+{
+	int i;
+
+	/* Reset CBUS */
+	mhl_tx_writebm(ctx, MHL_TX_SRST, ~0, 1 << 3);
+	/* CBUS deglitch - 2ms */
+	msleep(T_SRC_CBUS_DEGLITCH);
+	mhl_tx_writebm(ctx, MHL_TX_SRST, 0, 1 << 3);
+
+	for (i = 0; i < 4; i++) {
+		/* Enable WRITE_STAT interrupt for writes to all
+		 * 4 MSC Status registers.
+		 */
+		cbus_writeb(ctx, 0xE0 + i, 0xF2);
+		/* Enable SET_INT interrupt for writes to all
+		 * 4 MSC Interrupt registers.
+		 */
+		cbus_writeb(ctx, 0xF0 + i, 0xF2);
+	}
+
+	return sii9234_clear_error(ctx);
+}
+
+/* require to chek mhl imformation of samsung in cbus_init_register*/
+static int sii9234_cbus_init(struct sii9234 *ctx)
+{
+	cbus_writeb(ctx, 0x07, 0xF2);
+	cbus_writeb(ctx, 0x40, 0x03);
+	cbus_writeb(ctx, 0x42, 0x06);
+	cbus_writeb(ctx, 0x36, 0x0C);
+	cbus_writeb(ctx, 0x3D, 0xFD);
+	cbus_writeb(ctx, 0x1C, 0x01);
+	cbus_writeb(ctx, 0x1D, 0x0F);
+	cbus_writeb(ctx, 0x44, 0x02);
+	/* Setup our devcap */
+	/* To meet cts 6.3.10.1 spec */
+	cbus_writeb(ctx, CBUS_DEVCAP_DEV_STATE, 0x00);
+	/* mhl version 1.1 */
+	cbus_writeb(ctx, CBUS_DEVCAP_MHL_VERSION, 0x11);
+	cbus_writeb(ctx, CBUS_DEVCAP_DEV_CAT, 0x02);
+	cbus_writeb(ctx, CBUS_DEVCAP_ADOPTER_ID_H, 0x01);
+	cbus_writeb(ctx, CBUS_DEVCAP_ADOPTER_ID_L, 0x41);
+	/* YCbCr444, RGB444 */
+	cbus_writeb(ctx, CBUS_DEVCAP_VID_LINK_MODE, 0x03);
+	cbus_writeb(ctx, CBUS_DEVCAP_VIDEO_TYPE, 0);
+	cbus_writeb(ctx, CBUS_DEVCAP_LOG_DEV_MAP, 0x80);
+	cbus_writeb(ctx, CBUS_DEVCAP_BANDWIDTH, 0x0F);
+	cbus_writeb(ctx, CBUS_DEVCAP_DEV_FEATURE_FLAG, 0x07);
+	cbus_writeb(ctx, CBUS_DEVCAP_DEVICE_ID_H, 0x0);
+	cbus_writeb(ctx, CBUS_DEVCAP_DEVICE_ID_L, 0x0);
+	cbus_writeb(ctx, CBUS_DEVCAP_SCRATCHPAD_SIZE, 0x10);
+	cbus_writeb(ctx, CBUS_DEVCAP_INT_STAT_SIZE, 0x33);
+	cbus_writeb(ctx, CBUS_DEVCAP_RESERVED, 0);
+	cbus_writebm(ctx, 0x31, 0x0C, 0x0C);
+	cbus_writeb(ctx, 0x30, 0x01);
+	cbus_writebm(ctx, 0x3C, 0x30, 0x38);
+	cbus_writebm(ctx, 0x22, 0x0D, 0x0F);
+	cbus_writebm(ctx, 0x2E, 0x15, 0x15);
+	cbus_writeb(ctx, CBUS_INTR1_ENABLE_REG, 0);
+	cbus_writeb(ctx, CBUS_INTR2_ENABLE_REG, 0);
+
+	return sii9234_clear_error(ctx);
+}
+
+static void force_usb_id_switch_open(struct sii9234 *ctx)
+{
+	/*Disable CBUS discovery */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0, 0x01);
+	/*Force USB ID switch to open */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
+	/*Force upstream HPD to 0 when not in MHL mode. */
+	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x30);
+}
+
+static void release_usb_id_switch_open(struct sii9234 *ctx)
+{
+	msleep(T_SRC_CBUS_FLOAT);
+	/* clear USB ID switch to open */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0, USB_ID_OVR);
+	/* Enable CBUS discovery */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 0x01);
+}
+
+static int sii9234_power_init(struct sii9234 *ctx)
+{
+	/* Force the SiI9234 into the D0 state. */
+	tpi_writeb(ctx, TPI_DPD_REG, 0x3F);
+	/* Enable TxPLL Clock */
+	hdmi_writeb(ctx, HDMI_RX_TMDS_CLK_EN_REG, 0x01);
+	/* Enable Tx Clock Path & Equalizer */
+	hdmi_writeb(ctx, HDMI_RX_TMDS_CH_EN_REG, 0x15);
+	/* Power Up TMDS */
+	mhl_tx_writeb(ctx, 0x08, 0x35);
+	return sii9234_clear_error(ctx);
+}
+
+static int sii9234_hdmi_init(struct sii9234 *ctx)
+{
+	/* Analog PLL Control bits 5:4 = 2b00 as per char. team. */
+	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
+	/* PLL Calrefsel */
+	hdmi_writeb(ctx, HDMI_RX_PLL_CALREFSEL_REG, 0x03);
+	/* VCO Cal */
+	hdmi_writeb(ctx, HDMI_RX_PLL_VCOCAL_REG, 0x20);
+	/* Auto EQ */
+	hdmi_writeb(ctx, HDMI_RX_EQ_DATA0_REG, 0x8A);
+	/* Auto EQ */
+	hdmi_writeb(ctx, HDMI_RX_EQ_DATA1_REG, 0x6A);
+	/* Auto EQ */
+	hdmi_writeb(ctx, HDMI_RX_EQ_DATA2_REG, 0xAA);
+	/* Auto EQ */
+	hdmi_writeb(ctx, HDMI_RX_EQ_DATA3_REG, 0xCA);
+	/* Auto EQ */
+	hdmi_writeb(ctx, HDMI_RX_EQ_DATA4_REG, 0xEA);
+	/* Manual zone */
+	hdmi_writeb(ctx, HDMI_RX_TMDS_ZONE_CTRL_REG, 0xA0);
+	/* PLL Mode Value */
+	hdmi_writeb(ctx, HDMI_RX_TMDS_MODE_CTRL_REG, 0x00);
+	mhl_tx_writeb(ctx, MHL_TX_TMDS_CCTRL, 0x34);
+	hdmi_writeb(ctx, 0x45, 0x44);
+	/* Rx PLL BW ~ 4MHz */
+	hdmi_writeb(ctx, 0x31, 0x0A);
+	/* Analog PLL Control * bits 5:4 = 2b00 as per char. team. */
+	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
+
+	return sii9234_clear_error(ctx);
+}
+
+static int sii9234_mhl_tx_ctl_int(struct sii9234 *ctx)
+{
+	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0xD0);
+	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL2_REG, 0xFC);
+	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL4_REG, 0xEB);
+	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL7_REG, 0x0C);
+	return sii9234_clear_error(ctx);
+}
+
+static int sii9234_reset(struct sii9234 *ctx)
+{
+	int ret;
+
+	sii9234_clear_error(ctx);
+
+	ret = sii9234_power_init(ctx);
+	if (ret < 0)
+		return ret;
+	ret = sii9234_cbus_reset(ctx);
+	if (ret < 0)
+		return ret;
+	ret = sii9234_hdmi_init(ctx);
+	if (ret < 0)
+		return ret;
+	ret = sii9234_mhl_tx_ctl_int(ctx);
+	if (ret < 0)
+		return ret;
+
+	/* Enable HDCP Compliance safety */
+	mhl_tx_writeb(ctx, 0x2B, 0x01);
+	/* CBUS discovery cycle time for each drive and float = 150us */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0x04, 0x06);
+	/* Clear bit 6 (reg_skip_rgnd) */
+	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL2_REG, (1 << 7) /* Reserved */
+		| 2 << ATT_THRESH_SHIFT | DEGLITCH_TIME_50MS);
+	/* Changed from 66 to 65 for 94[1:0] = 01 = 5k reg_cbusmhl_pup_sel */
+	/* 1.8V CBUS VTH & GND threshold */
+	/*To meet CTS 3.3.7.2 spec */
+	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
+	/* set bit 2 and 3, which is Initiator Timeout */
+	cbus_writebm(ctx, CBUS_LINK_CONTROL_2_REG, ~0, 0x0C);
+	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL6_REG, 0xA0);
+	/* RGND & single discovery attempt (RGND blocking) */
+	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL6_REG, BLOCK_RGND_INT |
+			       DVRFLT_SEL | SINGLE_ATT);
+	/* Use VBUS path of discovery state machine */
+	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL8_REG, 0);
+	/* 0x92[3] sets the CBUS / ID switch */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
+	/* To allow RGND engine to operate correctly.
+	 * When moving the chip from D2 to D0 (power up, init regs)
+	 * the values should be
+	 * 94[1:0] = 01  reg_cbusmhl_pup_sel[1:0] should be set for 5k
+	 * 93[7:6] = 10  reg_cbusdisc_pup_sel[1:0] should be
+	 * set for 10k (default)
+	 * 93[5:4] = 00  reg_cbusidle_pup_sel[1:0] = open (default)
+	 */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
+	/* change from CC to 8C to match 5K */
+	/*To meet CTS 3.3.72 spec */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
+	/* Configure the interrupt as active high */
+	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x06);
+
+	msleep(25);
+
+	/* release usb_id switch */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0,  USB_ID_OVR);
+	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL1_REG, 0x27);
+
+	ret = sii9234_clear_error(ctx);
+	if (ret < 0)
+		return ret;
+	ret = sii9234_cbus_init(ctx);
+	if (ret < 0)
+		return ret;
+
+	/* Enable Auto soft reset on SCDT = 0 */
+	mhl_tx_writeb(ctx, 0x05, 0x04);
+	/* HDMI Transcode mode enable */
+	mhl_tx_writeb(ctx, 0x0D, 0x1C);
+	mhl_tx_writeb(ctx, MHL_TX_INTR4_ENABLE_REG,
+			       RGND_READY_MASK | CBUS_LKOUT_MASK |
+			       MHL_DISC_FAIL_MASK | MHL_EST_MASK);
+	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG, 0x60);
+
+	/* this point is very importand before megsure RGND impedance */
+	force_usb_id_switch_open(ctx);
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, 0, 0xF0);
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL5_REG, 0, 0x03);
+	release_usb_id_switch_open(ctx);
+	/*end of this */
+
+	/* Force upstream HPD to 0 when not in MHL mode */
+	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 1 << 5);
+	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, ~0, 1 << 4);
+
+	return sii9234_clear_error(ctx);
+}
+
+static int sii9234_goto_d3(struct sii9234 *ctx)
+{
+	int ret;
+
+	dev_dbg(ctx->dev, "sii9234: detection started d3\n");
+
+	ret = sii9234_reset(ctx);
+	if (ret < 0)
+		goto exit;
+
+	hdmi_writeb(ctx, 0x01, 0x03);
+	tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
+	/* I2C above is expected to fail because power goes down */
+	sii9234_clear_error(ctx);
+
+	ctx->state = ST_D3;
+
+	return 0;
+ exit:
+	dev_err(ctx->dev, "%s failed\n", __func__);
+	return -1;
+}
+
+#define sii9234_hw_on(sii9234) \
+	regulator_enable((sii9234)->vcc_supply)
+
+static void sii9234_hw_off(struct sii9234 *ctx)
+{
+	gpiod_set_value(ctx->gpio_reset, 0);
+	usleep_range(10000, 20000);
+	gpiod_set_value(ctx->gpio_reset, 1);
+	regulator_disable(ctx->vcc_supply);
+	gpiod_set_value(ctx->gpio_reset, 0);
+}
+
+static void sii9234_hw_reset(struct sii9234 *ctx)
+{
+	gpiod_set_value(ctx->gpio_reset, 0);
+	usleep_range(10000, 20000);
+	gpiod_set_value(ctx->gpio_reset, 1);
+}
+
+static void sii9234_cable_in(struct sii9234 *ctx)
+{
+	int ret;
+
+	mutex_lock(&ctx->lock);
+	if (ctx->state != ST_OFF)
+		goto unlock;
+	ret = sii9234_hw_on(ctx);
+	if (ret < 0)
+		goto unlock;
+
+	sii9234_hw_reset(ctx);
+	sii9234_goto_d3(ctx);
+	enable_irq(to_i2c_client(ctx->dev)->irq);
+
+unlock:
+	mutex_unlock(&ctx->lock);
+}
+
+static void sii9234_cable_out(struct sii9234 *ctx)
+{
+	mutex_lock(&ctx->lock);
+
+	if (ctx->state == ST_OFF)
+		goto unlock;
+
+	disable_irq(to_i2c_client(ctx->dev)->irq);
+	tpi_writeb(ctx, TPI_DPD_REG, 0);
+	/*turn on&off hpd festure for only QCT HDMI */
+	sii9234_hw_off(ctx);
+
+	ctx->state = ST_OFF;
+
+unlock:
+	mutex_unlock(&ctx->lock);
+}
+
+static enum sii9234_state sii9234_rgnd_ready_irq(struct sii9234 *ctx)
+{
+	int value;
+
+	if (ctx->state == ST_D3) {
+		int ret;
+
+		dev_dbg(ctx->dev, "RGND_READY_INT\n");
+		sii9234_hw_reset(ctx);
+
+		ret = sii9234_reset(ctx);
+		if (ret < 0) {
+			dev_err(ctx->dev, "sii9234_reset() failed\n");
+			return ST_FAILURE;
+		}
+
+		return ST_RGND_INIT;
+	}
+
+	/* got interrupt in inappropriate state */
+	if (ctx->state != ST_RGND_INIT)
+		return ST_FAILURE;
+
+	value = mhl_tx_readb(ctx, MHL_TX_STAT2_REG);
+	if (sii9234_clear_error(ctx))
+		return ST_FAILURE;
+
+	if ((value & RGND_INTP_MASK) != RGND_INTP_1K) {
+		dev_warn(ctx->dev, "RGND is not 1k\n");
+		return ST_RGND_INIT;
+	}
+	dev_dbg(ctx->dev, "RGND 1K!!\n");
+	/* After applying RGND patch, there is some issue
+	 * about discovry failure
+	 * This point is add to fix that problem
+	 */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
+	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, 0x05);
+	if (sii9234_clear_error(ctx))
+		return ST_FAILURE;
+
+	usleep_range(T_SRC_VBUS_CBUS_TO_STABLE * USEC_PER_MSEC,
+		     T_SRC_VBUS_CBUS_TO_STABLE * USEC_PER_MSEC);
+
+	return ST_RGND_1K;
+}
+
+static enum sii9234_state sii9234_mhl_established(struct sii9234 *ctx)
+{
+	dev_dbg(ctx->dev, "mhl est interrupt\n");
+
+	/* discovery override */
+	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0x10);
+	/* increase DDC translation layer timer (byte mode) */
+	cbus_writeb(ctx, 0x07, 0x32);
+	cbus_writebm(ctx, 0x44, ~0, 1 << 1);
+	/* Keep the discovery enabled. Need RGND interrupt */
+	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 1);
+	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG,
+	       RSEN_CHANGE_INT_MASK | HPD_CHANGE_INT_MASK);
+
+	if (sii9234_clear_error(ctx))
+		return ST_FAILURE;
+
+	return ST_MHL_ESTABLISHED;
+}
+
+static enum sii9234_state sii9234_hpd_change(struct sii9234 *ctx)
+{
+	int value;
+
+	value = cbus_readb(ctx, CBUS_MSC_REQ_ABORT_REASON_REG);
+	if (sii9234_clear_error(ctx))
+		return ST_FAILURE;
+
+	if (value & SET_HPD_DOWNSTREAM) {
+		dev_info(ctx->dev, "HPD High\n");
+		/* Downstream HPD High, Enable TMDS */
+		sii9234_tmds_control(ctx, true);
+		/*turn on&off hpd festure for only QCT HDMI */
+	} else {
+		dev_info(ctx->dev, "HPD Low\n");
+		/* Downstream HPD Low, Disable TMDS */
+		sii9234_tmds_control(ctx, false);
+	}
+
+	return ctx->state;
+}
+
+static enum sii9234_state sii9234_rsen_change(struct sii9234 *ctx)
+{
+	int value;
+
+	/* work_around code to handle worng interrupt */
+	if (ctx->state != ST_RGND_1K) {
+		dev_err(ctx->dev, "RSEN_HIGH without RGND_1K\n");
+		return ST_FAILURE;
+	}
+	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
+	if (value < 0)
+		return ST_FAILURE;
+
+	if (value & RSEN_STATUS) {
+		dev_info(ctx->dev, "MHL cable connected.. RSEN High\n");
+		return ST_RSEN_HIGH;
+	}
+	dev_info(ctx->dev, "RSEN lost\n");
+	/* Once RSEN loss is confirmed,we need to check
+	 * based on cable status and chip power status,whether
+	 * it is SINK Loss(HDMI cable not connected, TV Off)
+	 * or MHL cable disconnection
+	 * TODO: Define the below mhl_disconnection()
+	 */
+	msleep(T_SRC_RXSENSE_DEGLITCH);
+	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
+	if (value < 0)
+		return ST_FAILURE;
+	dev_dbg(ctx->dev, "sys_stat: %x\n", value);
+
+	if (value & RSEN_STATUS) {
+		dev_info(ctx->dev, "RSEN recovery\n");
+		return ST_RSEN_HIGH;
+	}
+	dev_info(ctx->dev, "RSEN Really LOW\n");
+	/*To meet CTS 3.3.22.2 spec */
+	sii9234_tmds_control(ctx, false);
+	force_usb_id_switch_open(ctx);
+	release_usb_id_switch_open(ctx);
+
+	return ST_FAILURE;
+}
+
+static irqreturn_t sii9234_irq_thread(int irq, void *data)
+{
+	struct sii9234 *ctx = data;
+	int intr1, intr4;
+	int intr1_en, intr4_en;
+	int cbus_intr1, cbus_intr2;
+
+	dev_dbg(ctx->dev, "%s\n", __func__);
+
+	msleep(30);
+
+	mutex_lock(&ctx->lock);
+
+	intr1 = mhl_tx_readb(ctx, MHL_TX_INTR1_REG);
+	intr4 = mhl_tx_readb(ctx, MHL_TX_INTR4_REG);
+	intr1_en = mhl_tx_readb(ctx, MHL_TX_INTR1_ENABLE_REG);
+	intr4_en = mhl_tx_readb(ctx, MHL_TX_INTR4_ENABLE_REG);
+	cbus_intr1 = cbus_readb(ctx, CBUS_INT_STATUS_1_REG);
+	cbus_intr2 = cbus_readb(ctx, CBUS_INT_STATUS_2_REG);
+
+	if (sii9234_clear_error(ctx))
+		goto done;
+
+	dev_dbg(ctx->dev, "irq %02x/%02x %02x/%02x %02x/%02x\n",
+		 intr1, intr1_en, intr4, intr4_en, cbus_intr1, cbus_intr2);
+
+	if (intr4 & RGND_READY_INT)
+		ctx->state = sii9234_rgnd_ready_irq(ctx);
+	if (intr1 & RSEN_CHANGE_INT)
+		ctx->state = sii9234_rsen_change(ctx);
+	if (intr4 & MHL_EST_INT)
+		ctx->state = sii9234_mhl_established(ctx);
+	if (intr1 & HPD_CHANGE_INT)
+		ctx->state = sii9234_hpd_change(ctx);
+	if (intr4 & CBUS_LKOUT_INT)
+		ctx->state = ST_FAILURE;
+	if (intr4 & MHL_DISC_FAIL_INT)
+		ctx->state = ST_FAILURE_DISCOVERY;
+
+ done:
+	/* clean interrupt status and pending flags */
+	mhl_tx_writeb(ctx, MHL_TX_INTR1_REG, intr1);
+	mhl_tx_writeb(ctx, MHL_TX_INTR4_REG, intr4);
+	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_0, 0xFF);
+	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_1, 0xFF);
+	cbus_writeb(ctx, CBUS_INT_STATUS_1_REG, cbus_intr1);
+	cbus_writeb(ctx, CBUS_INT_STATUS_2_REG, cbus_intr2);
+
+	sii9234_clear_error(ctx);
+
+	if (ctx->state == ST_FAILURE) {
+		dev_info(ctx->dev, "try to reset after failure\n");
+		sii9234_hw_reset(ctx);
+		sii9234_goto_d3(ctx);
+	}
+
+	if (ctx->state == ST_FAILURE_DISCOVERY) {
+		dev_err(ctx->dev, "discovery failed, no power for MHL?\n");
+		tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
+		ctx->state = ST_D3;
+	}
+
+	mutex_unlock(&ctx->lock);
+
+	return IRQ_HANDLED;
+}
+
+
+static int sii9234_init_resources(struct sii9234 *ctx,
+	struct i2c_client *client)
+{
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+
+	if (!ctx->dev->of_node) {
+		dev_err(ctx->dev, "not DT device\n");
+		return -ENODEV;
+	}
+
+	ctx->gpio_reset = devm_gpiod_get(ctx->dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(ctx->gpio_reset)) {
+		dev_err(ctx->dev, "failed to get reset gpio from DT\n");
+		return PTR_ERR(ctx->gpio_reset);
+	}
+
+	ctx->vcc_supply = devm_regulator_get(ctx->dev, "vcc");
+	if (IS_ERR(ctx->vcc_supply)) {
+		dev_err(ctx->dev, "failed to acquire regulator vcc\n");
+		return PTR_ERR(ctx->vcc_supply);
+	}
+
+	ctx->client[I2C_MHL] = client;
+
+	ctx->client[I2C_TPI] = i2c_new_dummy(adapter, 0x7A >> 1);
+	if (!ctx->client[I2C_TPI]) {
+		dev_err(ctx->dev, "failed to create TPI client\n");
+		return -ENODEV;
+	}
+
+	ctx->client[I2C_HDMI] = i2c_new_dummy(adapter, 0x92 >> 1);
+	if (!ctx->client[I2C_HDMI]) {
+		dev_err(ctx->dev, "failed to create HDMI RX client\n");
+		goto fail_tpi;
+	}
+
+	ctx->client[I2C_CBUS] = i2c_new_dummy(adapter, 0xC8 >> 1);
+	if (!ctx->client[I2C_CBUS]) {
+		dev_err(ctx->dev, "failed to create CBUS client\n");
+		goto fail_hdmi;
+	}
+
+	return 0;
+
+fail_hdmi:
+	i2c_unregister_device(ctx->client[I2C_HDMI]);
+fail_tpi:
+	i2c_unregister_device(ctx->client[I2C_TPI]);
+
+	return -ENODEV;
+}
+
+static void sii9234_deinit_resources(struct sii9234 *ctx)
+{
+	i2c_unregister_device(ctx->client[I2C_CBUS]);
+	i2c_unregister_device(ctx->client[I2C_HDMI]);
+	i2c_unregister_device(ctx->client[I2C_TPI]);
+}
+
+static inline struct sii9234 *bridge_to_sii9234(struct drm_bridge *bridge)
+{
+	return container_of(bridge, struct sii9234, bridge);
+}
+
+static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
+					const struct drm_display_mode *mode)
+{
+	struct sii9234 *ctx = bridge_to_sii9234(bridge);
+
+	if (mode->clock > MHL1_MAX_CLK)
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
+static const struct drm_bridge_funcs sii9234_bridge_funcs = {
+	.mode_valid = sii9234_mode_valid,
+};
+
+static int sii9234_mhl_tx_i2c_probe(struct i2c_client *client,
+					      const struct i2c_device_id *id)
+{
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+	struct sii9234 *ctx;
+	struct device *dev = &client->dev;
+	int ret;
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->dev = dev;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
+		dev_err(dev, "I2C adapter lacks SMBUS feature\n");
+		return -EIO;
+	}
+
+	mutex_init(&ctx->lock);
+
+	ret = sii9234_init_resources(ctx, client);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to initialize sii9234 resources\n");
+		return ret;
+	}
+	ret = sii9234_hw_on(ctx);
+	if (ret) {
+		dev_err(&client->dev, "failed to enable power\n");
+		goto err_resource;
+	}
+	sii9234_hw_reset(ctx);
+
+	if (!client->irq) {
+		dev_err(dev, "no irq provided\n");
+		return -EINVAL;
+	}
+	irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
+	ret = devm_request_threaded_irq(dev, client->irq, NULL,
+					sii9234_irq_thread,
+					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+					"sii9234", ctx);
+	if (ret < 0) {
+		dev_err(dev, "failed to install IRQ handler\n");
+		return ret;
+	}
+
+	i2c_set_clientdata(client, ctx);
+
+	ctx->bridge.funcs = &sii9234_bridge_funcs;
+	ctx->bridge.of_node = dev->of_node;
+	drm_bridge_add(&ctx->bridge);
+
+	sii9234_cable_in(ctx);
+
+	return 0;
+
+err_resource:
+	sii9234_deinit_resources(ctx);
+
+	return ret;
+}
+
+static int sii9234_mhl_tx_i2c_remove(struct i2c_client *client)
+{
+	struct sii9234 *ctx = i2c_get_clientdata(client);
+
+	sii9234_cable_out(ctx);
+	drm_bridge_remove(&ctx->bridge);
+	sii9234_deinit_resources(ctx);
+
+	return 0;
+}
+
+static const struct of_device_id sii9234_dt_match[] = {
+	{ .compatible = "sil,sii9234" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, sii9234_dt_match);
+
+static const struct i2c_device_id sii9234_id[] = {
+	{ "SII9234", 0 },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(i2c, sii9234_id);
+static struct i2c_driver sii9234_driver = {
+	.driver = {
+		.name	= "sii9234",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(sii9234_dt_match),
+	},
+	.probe		= sii9234_mhl_tx_i2c_probe,
+	.remove		= sii9234_mhl_tx_i2c_remove,
+	.id_table = sii9234_id,
+};
+
+module_i2c_driver(sii9234_driver);
+MODULE_LICENSE("GPL");