[v2,2/2] media: i2c: Add driver for ST VD56G3 camera sensor

Add V4L2 sub-device driver for STMicroelectronics VD56G3 camera sensor.
This is a 1.5 M pixel global shutter image sensor with an active array
size of 1124 x 1364 (portrait orientation).

The driver supports Mono (VD56G3) and Color (VD66GY) variants.

Signed-off-by: Sylvain Petinot <sylvain.petinot@foss.st.com>
---
 drivers/media/i2c/Kconfig     |   11 +
 drivers/media/i2c/Makefile    |    1 +
 drivers/media/i2c/st-vd56g3.c | 1608 +++++++++++++++++++++++++++++++++
 3 files changed, 1620 insertions(+)
 create mode 100644 drivers/media/i2c/st-vd56g3.c

Hi Sylvain,

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

On Tue, May 21, 2024 at 06:29:50PM +0200, Sylvain Petinot wrote:
> Add V4L2 sub-device driver for STMicroelectronics VD56G3 camera sensor.
> This is a 1.5 M pixel global shutter image sensor with an active array
> size of 1124 x 1364 (portrait orientation).
> 
> The driver supports Mono (VD56G3) and Color (VD66GY) variants.
> 
> Signed-off-by: Sylvain Petinot <sylvain.petinot@foss.st.com>
> ---
>  drivers/media/i2c/Kconfig     |   11 +
>  drivers/media/i2c/Makefile    |    1 +
>  drivers/media/i2c/st-vd56g3.c | 1608 +++++++++++++++++++++++++++++++++
>  3 files changed, 1620 insertions(+)
>  create mode 100644 drivers/media/i2c/st-vd56g3.c
> 
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index c6d3ee472d81..c3d3cbdfcb3b 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -659,6 +659,17 @@ config VIDEO_S5K6A3
>  	  This is a V4L2 sensor driver for Samsung S5K6A3 raw
>  	  camera sensor.
>  
> +config VIDEO_ST_VD56G3
> +	tristate "ST VD56G3 sensor support"
> +	select V4L2_CCI_I2C
> +	depends on OF && GPIOLIB
> +	help
> +	  This is a Video4Linux2 sensor driver for the ST VD56G3
> +	  camera sensor.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called st-vd56g3.
> +
>  config VIDEO_ST_VGXY61
>  	tristate "ST VGXY61 sensor support"
>  	select V4L2_CCI_I2C
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index dfbe6448b549..b469cf0f8113 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -124,6 +124,7 @@ obj-$(CONFIG_VIDEO_SAA717X) += saa717x.o
>  obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o
>  obj-$(CONFIG_VIDEO_SONY_BTF_MPX) += sony-btf-mpx.o
>  obj-$(CONFIG_VIDEO_ST_MIPID02) += st-mipid02.o
> +obj-$(CONFIG_VIDEO_ST_VD56G3) += st-vd56g3.o
>  obj-$(CONFIG_VIDEO_ST_VGXY61) += st-vgxy61.o
>  obj-$(CONFIG_VIDEO_TC358743) += tc358743.o
>  obj-$(CONFIG_VIDEO_TC358746) += tc358746.o
> diff --git a/drivers/media/i2c/st-vd56g3.c b/drivers/media/i2c/st-vd56g3.c
> new file mode 100644
> index 000000000000..1e4329502230
> --- /dev/null
> +++ b/drivers/media/i2c/st-vd56g3.c
> @@ -0,0 +1,1608 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * A V4L2 driver for ST VD56G3 (Mono) and VD66GY (RGB) global shutter cameras.
> + * Copyright (C) 2024, STMicroelectronics SA
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/units.h>
> +
> +#include <asm/unaligned.h>
> +
> +#include <media/mipi-csi2.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-cci.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-subdev.h>
> +
> +/* Register Map */
> +#define VD56G3_REG_MODEL_ID				CCI_REG16_LE(0x0000)
> +#define VD56G3_MODEL_ID					0x5603
> +#define VD56G3_REG_REVISION				CCI_REG16_LE(0x0002)
> +#define VD56G3_REVISION_CUT3				0x31
> +#define VD56G3_REG_OPTICAL_REVISION			CCI_REG8(0x001a)
> +#define VD56G3_OPTICAL_REVISION_MONO			0
> +#define VD56G3_OPTICAL_REVISION_BAYER			1
> +#define VD56G3_REG_SYSTEM_FSM				CCI_REG8(0x0028)
> +#define VD56G3_SYSTEM_FSM_READY_TO_BOOT			0x01
> +#define VD56G3_SYSTEM_FSM_SW_STBY			0x02
> +#define VD56G3_SYSTEM_FSM_STREAMING			0x03
> +#define VD56G3_REG_APPLIED_COARSE_EXPOSURE		CCI_REG16_LE(0x0064)
> +#define VD56G3_REG_APPLIED_ANALOG_GAIN			CCI_REG8(0x0068)
> +#define VD56G3_REG_APPLIED_DIGITAL_GAIN			CCI_REG16_LE(0x006a)
> +#define VD56G3_REG_BOOT					CCI_REG8(0x0200)
> +#define VD56G3_CMD_ACK					0
> +#define VD56G3_CMD_BOOT					1
> +#define VD56G3_REG_STBY					CCI_REG8(0x0201)
> +#define VD56G3_CMD_START_STREAM				1
> +#define VD56G3_REG_STREAMING				CCI_REG8(0x0202)
> +#define VD56G3_CMD_STOP_STREAM				1
> +#define VD56G3_REG_EXT_CLOCK				CCI_REG32_LE(0x0220)
> +#define VD56G3_REG_CLK_PLL_PREDIV			CCI_REG8(0x0224)
> +#define VD56G3_REG_CLK_SYS_PLL_MULT			CCI_REG8(0x0226)
> +#define VD56G3_REG_ORIENTATION				CCI_REG8(0x0302)
> +#define VD56G3_REG_FORMAT_CTRL				CCI_REG8(0x030a)
> +#define VD56G3_REG_OIF_CTRL				CCI_REG16_LE(0x030c)
> +#define VD56G3_REG_OIF_IMG_CTRL				CCI_REG8(0x030f)
> +#define VD56G3_REG_OIF_CSI_BITRATE			CCI_REG16_LE(0x0312)
> +#define VD56G3_REG_DUSTER_CTRL				CCI_REG8(0x0318)
> +#define VD56G3_DUSTER_DISABLE				0
> +#define VD56G3_DUSTER_ENABLE_DEF_MODULES		0x13
> +#define VD56G3_REG_ISL_ENABLE				CCI_REG8(0x0333)
> +#define VD56G3_REG_DARKCAL_CTRL				CCI_REG8(0x0340)
> +#define VD56G3_DARKCAL_ENABLE				1
> +#define VD56G3_DARKCAL_DISABLE_DARKAVG			2
> +#define VD56G3_REG_PATGEN_CTRL				CCI_REG16_LE(0x0400)
> +#define VD56G3_PATGEN_ENABLE				1
> +#define VD56G3_PATGEN_TYPE_SHIFT			4
> +#define VD56G3_REG_AE_COLDSTART_COARSE_EXPOSURE		CCI_REG16_LE(0x042a)
> +#define VD56G3_REG_AE_COLDSTART_ANALOG_GAIN		CCI_REG8(0x042c)
> +#define VD56G3_REG_AE_COLDSTART_DIGITAL_GAIN		CCI_REG16_LE(0x042e)
> +#define VD56G3_REG_AE_ROI_START_H			CCI_REG16_LE(0x0432)
> +#define VD56G3_REG_AE_ROI_START_V			CCI_REG16_LE(0x0434)
> +#define VD56G3_REG_AE_ROI_END_H				CCI_REG16_LE(0x0436)
> +#define VD56G3_REG_AE_ROI_END_V				CCI_REG16_LE(0x0438)
> +#define VD56G3_REG_AE_COMPENSATION			CCI_REG16_LE(0x043a)
> +#define VD56G3_REG_EXP_MODE				CCI_REG8(0x044c)
> +#define VD56G3_EXP_MODE_AUTO				0
> +#define VD56G3_EXP_MODE_FREEZE				1
> +#define VD56G3_EXP_MODE_MANUAL				2
> +#define VD56G3_REG_MANUAL_ANALOG_GAIN			CCI_REG8(0x044d)
> +#define VD56G3_REG_MANUAL_COARSE_EXPOSURE		CCI_REG16_LE(0x044e)
> +#define VD56G3_REG_MANUAL_DIGITAL_GAIN_CH0		CCI_REG16_LE(0x0450)
> +#define VD56G3_REG_MANUAL_DIGITAL_GAIN_CH1		CCI_REG16_LE(0x0452)
> +#define VD56G3_REG_MANUAL_DIGITAL_GAIN_CH2		CCI_REG16_LE(0x0454)
> +#define VD56G3_REG_MANUAL_DIGITAL_GAIN_CH3		CCI_REG16_LE(0x0456)
> +#define VD56G3_REG_FRAME_LENGTH				CCI_REG16_LE(0x0458)
> +#define VD56G3_REG_Y_START				CCI_REG16_LE(0x045a)
> +#define VD56G3_REG_Y_END				CCI_REG16_LE(0x045c)
> +#define VD56G3_REG_OUT_ROI_X_START			CCI_REG16_LE(0x045e)
> +#define VD56G3_REG_OUT_ROI_X_END			CCI_REG16_LE(0x0460)
> +#define VD56G3_REG_OUT_ROI_Y_START			CCI_REG16_LE(0x0462)
> +#define VD56G3_REG_OUT_ROI_Y_END			CCI_REG16_LE(0x0464)
> +#define VD56G3_REG_GPIO_0_CTRL				CCI_REG8(0x0467)
> +#define VD56G3_GPIOX_GPIO_IN				0x01
> +#define VD56G3_GPIOX_STROBE_MODE			0x02
> +#define VD56G3_REG_READOUT_CTRL				CCI_REG8(0x047e)
> +#define READOUT_NORMAL					0x00
> +#define READOUT_DIGITAL_BINNING_X2			0x01
> +
> +/*
> + * The VD56G3 pixel array is organized as follows:
> + *
> + * +--------------------------------+
> + * |                                | \
> + * |   +------------------------+   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   |   Default resolution   |   |  | Native height (1364)

What's outside the default resolution? It doesn't appear the driver would
allow capturing pixels out side this area.

> + * |   |      1120 x 1360       |   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   |                        |   |  |
> + * |   +------------------------+   |  |
> + * |                                | /
> + * +--------------------------------+
> + *   <----------------------------->
> + *                     \-------------------  Native width (1124)
> + *
> + * The native resolution is 1124x1364.
> + * The recommended/default resolution is 1120x1360 (multiple of 16).
> + */
> +#define VD56G3_NATIVE_WIDTH				1124
> +#define VD56G3_NATIVE_HEIGHT				1364
> +#define VD56G3_DEFAULT_WIDTH				1120
> +#define VD56G3_DEFAULT_HEIGHT				1360
> +#define VD56G3_DEFAULT_MODE				1
> +
> +/* PLL settings */
> +#define VD56G3_TARGET_PLL				804000000UL
> +#define VD56G3_VT_CLOCK_DIV				5
> +
> +/* Line length and Frame length (settings are for standard 10bits ADC mode) */
> +#define VD56G3_LINE_LENGTH_MIN				1236
> +#define VD56G3_VBLANK_MIN				110
> +#define VD56G3_FRAME_LENGTH_DEF_60FPS			2168
> +
> +/* Exposure settings */
> +#define VD56G3_EXPOSURE_MARGIN				75
> +#define VD56G3_EXPOSURE_DEFAULT				1420
> +
> +/* Output Interface settings */
> +#define VD56G3_MAX_CSI_DATA_LANES			2
> +#define VD56G3_LINK_FREQ_DEF_1LANE			750000000UL
> +#define VD56G3_LINK_FREQ_DEF_2LANES			402000000UL
> +
> +/* GPIOs */
> +#define VD56G3_NB_GPIOS					8
> +
> +/* regulator supplies */
> +static const char *const vd56g3_supply_names[] = {
> +	"vcore",
> +	"vddio",
> +	"vana",
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Models (VD56G3: Mono, VD66GY: Bayer RGB), Modes and formats
> + */
> +
> +enum vd56g3_models {
> +	VD56G3_MODEL_VD56G3,
> +	VD56G3_MODEL_VD66GY,
> +};
> +
> +struct vd56g3_mode {
> +	u32 width;
> +	u32 height;
> +};
> +
> +static const struct vd56g3_mode vd56g3_supported_modes[] = {
> +	{
> +		.width = VD56G3_NATIVE_WIDTH,
> +		.height = VD56G3_NATIVE_HEIGHT,
> +	},
> +	{
> +		.width = VD56G3_DEFAULT_WIDTH,
> +		.height = VD56G3_DEFAULT_HEIGHT,
> +	},
> +	{
> +		.width = 1024,
> +		.height = 1280,
> +	},
> +	{
> +		.width = 1024,
> +		.height = 768,
> +	},
> +	{
> +		.width = 768,
> +		.height = 1024,
> +	},
> +	{
> +		.width = 720,
> +		.height = 1280,
> +	},
> +	{
> +		.width = 640,
> +		.height = 480,
> +	},
> +	{
> +		.width = 480,
> +		.height = 640,
> +	},
> +	{
> +		.width = 320,
> +		.height = 240,
> +	},
> +};
> +
> +/*
> + * Sensor support 8bits and 10bits output in both variants
> + *  - Monochrome
> + *  - RGB (with all H/V flip variations)
> + */
> +static const unsigned int vd56g3_mbus_codes[2][5] = {
> +	{
> +		MEDIA_BUS_FMT_Y8_1X8,
> +		MEDIA_BUS_FMT_SGRBG8_1X8,
> +		MEDIA_BUS_FMT_SRGGB8_1X8,
> +		MEDIA_BUS_FMT_SBGGR8_1X8,
> +		MEDIA_BUS_FMT_SGBRG8_1X8,
> +	},
> +	{
> +		MEDIA_BUS_FMT_Y10_1X10,
> +		MEDIA_BUS_FMT_SGRBG10_1X10,
> +		MEDIA_BUS_FMT_SRGGB10_1X10,
> +		MEDIA_BUS_FMT_SBGGR10_1X10,
> +		MEDIA_BUS_FMT_SGBRG10_1X10,
> +	},
> +};
> +
> +enum vd56g3_expo_state {
> +	VD56G3_EXPO_AUTO,
> +	VD56G3_EXPO_AUTO_FREEZE,
> +	VD56G3_EXPO_MANUAL
> +};
> +
> +struct vd56g3 {
> +	struct i2c_client *i2c_client;
> +	struct v4l2_subdev sd;
> +	struct media_pad pad;
> +	struct regulator_bulk_data supplies[ARRAY_SIZE(vd56g3_supply_names)];
> +	struct gpio_desc *reset_gpio;
> +	struct clk *xclk;
> +	struct regmap *regmap;
> +	u32 xclk_freq;
> +	u32 pll_prediv;
> +	u32 pll_mult;
> +	u32 pixel_clock;
> +	u16 oif_ctrl;
> +	u8 nb_of_lane;
> +	u32 gpios[VD56G3_NB_GPIOS];
> +	unsigned long ext_leds_mask;
> +	bool is_mono;
> +	struct v4l2_ctrl_handler ctrl_handler;
> +	struct v4l2_ctrl *hblank_ctrl;
> +	struct v4l2_ctrl *vblank_ctrl;
> +	struct {
> +		struct v4l2_ctrl *hflip_ctrl;
> +		struct v4l2_ctrl *vflip_ctrl;
> +	};
> +	struct v4l2_ctrl *patgen_ctrl;
> +	struct {
> +		struct v4l2_ctrl *ae_ctrl;
> +		struct v4l2_ctrl *expo_ctrl;
> +		struct v4l2_ctrl *again_ctrl;
> +		struct v4l2_ctrl *dgain_ctrl;
> +	};
> +	struct v4l2_ctrl *ae_lock_ctrl;
> +	struct v4l2_ctrl *ae_bias_ctrl;
> +	struct v4l2_ctrl *led_ctrl;
> +	bool streaming;
> +};
> +
> +static inline struct vd56g3 *to_vd56g3(struct v4l2_subdev *sd)
> +{
> +	return container_of_const(sd, struct vd56g3, sd);
> +}
> +
> +static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
> +{
> +	return &container_of_const(ctrl->handler, struct vd56g3, ctrl_handler)
> +			->sd;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Additional i2c register helpers
> + */
> +
> +static int vd56g3_poll_reg(struct vd56g3 *sensor, u32 reg, u8 poll_val,
> +			   int *err)
> +{
> +	unsigned int val = 0;
> +	int ret;
> +
> +	if (err && *err)
> +		return *err;
> +
> +	ret = regmap_read_poll_timeout(sensor->regmap, CCI_REG_ADDR(reg), val,
> +				       (val == poll_val), 2000,
> +				       500 * USEC_PER_MSEC);
> +
> +	if (ret && err)
> +		*err = ret;
> +
> +	return ret;
> +}
> +
> +static int vd56g3_wait_state(struct vd56g3 *sensor, int state, int *err)
> +{
> +	return vd56g3_poll_reg(sensor, VD56G3_REG_SYSTEM_FSM, state, err);
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Controls: definitions, helpers and handlers
> + */
> +
> +static const char *const vd56g3_tp_menu[] = { "Disabled", "Solid", "Colorbar",
> +					      "Gradbar",  "Hgrey", "Vgrey",
> +					      "Dgrey",	  "PN28" };
> +
> +static const s64 vd56g3_ev_bias_qmenu[] = { -4000, -3500, -3000, -2500, -2000,
> +					    -1500, -1000, -500,	 0,	500,
> +					    1000,  1500,  2000,	 2500,	3000,
> +					    3500,  4000 };
> +
> +static const s64 vd56g3_link_freq_1lane[] = { VD56G3_LINK_FREQ_DEF_1LANE };
> +
> +static const s64 vd56g3_link_freq_2lanes[] = { VD56G3_LINK_FREQ_DEF_2LANES };
> +
> +static u8 vd56g3_get_bpp(__u32 code)
> +{
> +	switch (code) {
> +	case MEDIA_BUS_FMT_Y8_1X8:
> +	case MEDIA_BUS_FMT_SGRBG8_1X8:
> +	case MEDIA_BUS_FMT_SRGGB8_1X8:
> +	case MEDIA_BUS_FMT_SBGGR8_1X8:
> +	case MEDIA_BUS_FMT_SGBRG8_1X8:
> +	default:
> +		return 8;
> +	case MEDIA_BUS_FMT_Y10_1X10:
> +	case MEDIA_BUS_FMT_SGRBG10_1X10:
> +	case MEDIA_BUS_FMT_SRGGB10_1X10:
> +	case MEDIA_BUS_FMT_SBGGR10_1X10:
> +	case MEDIA_BUS_FMT_SGBRG10_1X10:
> +		return 10;
> +	}
> +}
> +
> +static u8 vd56g3_get_datatype(__u32 code)
> +{
> +	switch (code) {
> +	case MEDIA_BUS_FMT_Y8_1X8:
> +	case MEDIA_BUS_FMT_SGRBG8_1X8:
> +	case MEDIA_BUS_FMT_SRGGB8_1X8:
> +	case MEDIA_BUS_FMT_SBGGR8_1X8:
> +	case MEDIA_BUS_FMT_SGBRG8_1X8:
> +	default:
> +		return MIPI_CSI2_DT_RAW8;
> +	case MEDIA_BUS_FMT_Y10_1X10:
> +	case MEDIA_BUS_FMT_SGRBG10_1X10:
> +	case MEDIA_BUS_FMT_SRGGB10_1X10:
> +	case MEDIA_BUS_FMT_SBGGR10_1X10:
> +	case MEDIA_BUS_FMT_SGBRG10_1X10:
> +		return MIPI_CSI2_DT_RAW10;
> +	}
> +}
> +
> +static int vd56g3_read_expo_cluster(struct vd56g3 *sensor, bool force_cur_val)
> +{
> +	u64 exposure = 0;
> +	u64 again = 0;
> +	u64 dgain = 0;
> +	int ret = 0;
> +
> +	/*
> +	 * When 'force_cur_val' is enabled, save the ctrl value in 'cur.val'
> +	 * instead of the normal 'val', this is used during poweroff to cache
> +	 * volatile ctrls and enable coldstart.
> +	 */
> +	cci_read(sensor->regmap, VD56G3_REG_APPLIED_COARSE_EXPOSURE, &exposure,
> +		 &ret);
> +	cci_read(sensor->regmap, VD56G3_REG_APPLIED_ANALOG_GAIN, &again, &ret);
> +	cci_read(sensor->regmap, VD56G3_REG_APPLIED_DIGITAL_GAIN, &dgain, &ret);
> +	if (ret)
> +		return ret;
> +
> +	if (force_cur_val) {
> +		sensor->expo_ctrl->cur.val = exposure;
> +		sensor->again_ctrl->cur.val = again;
> +		sensor->dgain_ctrl->cur.val = dgain;
> +	} else {
> +		sensor->expo_ctrl->val = exposure;
> +		sensor->again_ctrl->val = again;
> +		sensor->dgain_ctrl->val = dgain;
> +	}
> +
> +	return ret;
> +}
> +
> +static int vd56g3_update_patgen(struct vd56g3 *sensor, u32 patgen_index)
> +{
> +	u32 pattern = patgen_index <= 3 ? patgen_index : patgen_index + 12;
> +	u16 patgen = pattern << VD56G3_PATGEN_TYPE_SHIFT;
> +	u8 duster = VD56G3_DUSTER_ENABLE_DEF_MODULES;
> +	u8 darkcal = VD56G3_DARKCAL_ENABLE;
> +	int ret = 0;
> +
> +	if (patgen_index) {
> +		patgen |= VD56G3_PATGEN_ENABLE;
> +		duster = VD56G3_DUSTER_DISABLE;
> +		darkcal = VD56G3_DARKCAL_DISABLE_DARKAVG;
> +	}
> +
> +	cci_write(sensor->regmap, VD56G3_REG_DUSTER_CTRL, duster, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_DARKCAL_CTRL, darkcal, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_PATGEN_CTRL, patgen, &ret);
> +
> +	return ret;
> +}
> +
> +static int vd56g3_update_expo_cluster(struct vd56g3 *sensor, bool is_auto)
> +{
> +	enum vd56g3_expo_state expo_state = is_auto ? VD56G3_EXP_MODE_AUTO :
> +						      VD56G3_EXP_MODE_MANUAL;
> +	int ret = 0;
> +
> +	if (sensor->ae_ctrl->is_new)
> +		cci_write(sensor->regmap, VD56G3_REG_EXP_MODE, expo_state,
> +			  &ret);
> +
> +	/* In Auto expo, set coldstart parameters */
> +	if (is_auto && sensor->ae_ctrl->is_new) {
> +		cci_write(sensor->regmap,
> +			  VD56G3_REG_AE_COLDSTART_COARSE_EXPOSURE,
> +			  sensor->expo_ctrl->val, &ret);
> +		cci_write(sensor->regmap, VD56G3_REG_AE_COLDSTART_ANALOG_GAIN,
> +			  sensor->again_ctrl->val, &ret);
> +		cci_write(sensor->regmap, VD56G3_REG_AE_COLDSTART_DIGITAL_GAIN,
> +			  sensor->dgain_ctrl->val, &ret);
> +	}
> +
> +	/* In Manual expo, set exposure, analog and digital gains */
> +	if (!is_auto && sensor->expo_ctrl->is_new)
> +		cci_write(sensor->regmap, VD56G3_REG_MANUAL_COARSE_EXPOSURE,
> +			  sensor->expo_ctrl->val, &ret);
> +
> +	if (!is_auto && sensor->again_ctrl->is_new)
> +		cci_write(sensor->regmap, VD56G3_REG_MANUAL_ANALOG_GAIN,
> +			  sensor->again_ctrl->val, &ret);
> +
> +	if (!is_auto && sensor->dgain_ctrl->is_new) {
> +		cci_write(sensor->regmap, VD56G3_REG_MANUAL_DIGITAL_GAIN_CH0,
> +			  sensor->dgain_ctrl->val, &ret);
> +		cci_write(sensor->regmap, VD56G3_REG_MANUAL_DIGITAL_GAIN_CH1,
> +			  sensor->dgain_ctrl->val, &ret);
> +		cci_write(sensor->regmap, VD56G3_REG_MANUAL_DIGITAL_GAIN_CH2,
> +			  sensor->dgain_ctrl->val, &ret);
> +		cci_write(sensor->regmap, VD56G3_REG_MANUAL_DIGITAL_GAIN_CH3,
> +			  sensor->dgain_ctrl->val, &ret);
> +	}
> +
> +	return ret;
> +}
> +
> +static int vd56g3_lock_exposure(struct vd56g3 *sensor, u32 lock_val)
> +{
> +	bool ae_lock = lock_val & V4L2_LOCK_EXPOSURE;
> +	enum vd56g3_expo_state expo_state = ae_lock ? VD56G3_EXP_MODE_FREEZE :
> +						      VD56G3_EXP_MODE_AUTO;
> +	int ret = 0;
> +
> +	if (sensor->ae_ctrl->val == V4L2_EXPOSURE_AUTO)
> +		cci_write(sensor->regmap, VD56G3_REG_EXP_MODE, expo_state,

You can return cci_write's return value here.

> +			  &ret);
> +
> +	return ret;

And return 0 here.

> +}
> +
> +static int vd56g3_write_gpiox(struct vd56g3 *sensor, unsigned long gpio_mask)
> +{
> +	unsigned long io;
> +	u32 gpio_val;
> +	int ret = 0;
> +
> +	for_each_set_bit(io, &gpio_mask, VD56G3_NB_GPIOS) {
> +		gpio_val = sensor->gpios[io];
> +
> +		if (gpio_val == VD56G3_GPIOX_STROBE_MODE &&
> +		    sensor->led_ctrl->val == V4L2_FLASH_LED_MODE_NONE)
> +			gpio_val = VD56G3_GPIOX_GPIO_IN;
> +
> +		cci_write(sensor->regmap, VD56G3_REG_GPIO_0_CTRL + io, gpio_val,
> +			  &ret);
> +	}
> +
> +	return ret;
> +}
> +
> +static int vd56g3_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +	struct i2c_client *client = v4l2_get_subdevdata(sd);
> +	int ret = 0;
> +
> +	/* Interact with HW only when it is powered ON */
> +	if (!pm_runtime_get_if_in_use(&client->dev))
> +		return 0;
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_EXPOSURE_AUTO:
> +		ret = vd56g3_read_expo_cluster(sensor, false);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +		break;
> +	}
> +
> +	pm_runtime_mark_last_busy(&client->dev);
> +	pm_runtime_put_autosuspend(&client->dev);

This should be __pm_runtime_put_autosuspend(). pm_runtime_put_autosuspend()
will be re-purposed soon to include marking the last busy timestamp.

Same elsewhere in the driver.

> +
> +	return ret;
> +}
> +
> +static int vd56g3_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +	struct i2c_client *client = v4l2_get_subdevdata(sd);
> +	struct v4l2_subdev_state *state;
> +	const struct v4l2_rect *crop;
> +	unsigned int frame_length = 0;
> +	unsigned int expo_max;
> +	unsigned int ae_compensation;
> +	bool is_auto = false;
> +	int ret;
> +
> +	state = v4l2_subdev_get_locked_active_state(sd);
> +	crop = v4l2_subdev_state_get_crop(state, 0);
> +
> +	if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
> +		return 0;
> +
> +	/* Update controls state, range, etc. whatever the state of the HW */
> +	switch (ctrl->id) {
> +	case V4L2_CID_VBLANK:
> +		frame_length = crop->height + ctrl->val;
> +		expo_max = frame_length - VD56G3_EXPOSURE_MARGIN;
> +		__v4l2_ctrl_modify_range(sensor->expo_ctrl, 0, expo_max, 1,
> +					 VD56G3_EXPOSURE_DEFAULT);

__v4l2_ctrl_modify_range() may fail. Please handle the possible error.

> +		break;
> +	case V4L2_CID_EXPOSURE_AUTO:
> +		is_auto = (ctrl->val == V4L2_EXPOSURE_AUTO);
> +		__v4l2_ctrl_grab(sensor->ae_lock_ctrl, !is_auto);
> +		__v4l2_ctrl_grab(sensor->ae_bias_ctrl, !is_auto);
> +		break;
> +	default:
> +		break;

You could omit default here.

> +	}
> +
> +	/* Interact with HW only when it is powered ON */
> +	if (!pm_runtime_get_if_in_use(&client->dev))
> +		return 0;
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_HFLIP:
> +		ret = cci_write(sensor->regmap, VD56G3_REG_ORIENTATION,
> +				sensor->hflip_ctrl->val |
> +					(sensor->vflip_ctrl->val << 1),
> +				NULL);
> +		break;
> +	case V4L2_CID_TEST_PATTERN:
> +		ret = vd56g3_update_patgen(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_EXPOSURE_AUTO:
> +		ret = vd56g3_update_expo_cluster(sensor, is_auto);
> +		break;
> +	case V4L2_CID_3A_LOCK:
> +		ret = vd56g3_lock_exposure(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_AUTO_EXPOSURE_BIAS:
> +		ae_compensation =
> +			DIV_ROUND_CLOSEST((int)vd56g3_ev_bias_qmenu[ctrl->val] *
> +					  256, 1000);
> +		ret = cci_write(sensor->regmap, VD56G3_REG_AE_COMPENSATION,
> +				ae_compensation, NULL);
> +		break;
> +	case V4L2_CID_VBLANK:
> +		ret = cci_write(sensor->regmap, VD56G3_REG_FRAME_LENGTH,
> +				frame_length, NULL);
> +		break;
> +	case V4L2_CID_FLASH_LED_MODE:
> +		ret = vd56g3_write_gpiox(sensor, sensor->ext_leds_mask);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +		break;
> +	}
> +
> +	pm_runtime_mark_last_busy(&client->dev);
> +	pm_runtime_put_autosuspend(&client->dev);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_ctrl_ops vd56g3_ctrl_ops = {
> +	.g_volatile_ctrl = vd56g3_g_volatile_ctrl,
> +	.s_ctrl = vd56g3_s_ctrl,
> +};
> +
> +static int vd56g3_update_controls(struct vd56g3 *sensor)
> +{
> +	struct v4l2_subdev_state *state;
> +	const struct v4l2_rect *crop;
> +	unsigned int hblank;
> +	unsigned int vblank_min, vblank, vblank_max;
> +	unsigned int frame_length;
> +	unsigned int expo_max;
> +	int ret;
> +
> +	state = v4l2_subdev_get_locked_active_state(&sensor->sd);
> +	crop = v4l2_subdev_state_get_crop(state, 0);
> +	hblank = VD56G3_LINE_LENGTH_MIN - crop->width;
> +	vblank_min = VD56G3_VBLANK_MIN;
> +	vblank = VD56G3_FRAME_LENGTH_DEF_60FPS - crop->height;
> +	vblank_max = 0xffff - crop->height;

How about adding a corresponding FRAME_LENGTH_MAX macro for 0xffff?

> +	frame_length = crop->height + vblank;
> +	expo_max = frame_length - VD56G3_EXPOSURE_MARGIN;
> +
> +	/* Update blanking and exposure (ranges + values) */
> +	ret = __v4l2_ctrl_modify_range(sensor->hblank_ctrl, hblank, hblank, 1,
> +				       hblank);
> +	if (ret)
> +		return ret;
> +
> +	ret = __v4l2_ctrl_modify_range(sensor->vblank_ctrl, vblank_min,
> +				       vblank_max, 1, vblank);
> +	if (ret)
> +		return ret;
> +
> +	ret = __v4l2_ctrl_s_ctrl(sensor->vblank_ctrl, vblank);
> +	if (ret)
> +		return ret;
> +
> +	ret = __v4l2_ctrl_modify_range(sensor->expo_ctrl, 0, expo_max, 1,
> +				       VD56G3_EXPOSURE_DEFAULT);
> +	if (ret)
> +		return ret;
> +
> +	return __v4l2_ctrl_s_ctrl(sensor->expo_ctrl, VD56G3_EXPOSURE_DEFAULT);
> +}
> +
> +static int vd56g3_init_controls(struct vd56g3 *sensor)
> +{
> +	const struct v4l2_ctrl_ops *ops = &vd56g3_ctrl_ops;
> +	struct v4l2_ctrl_handler *hdl = &sensor->ctrl_handler;
> +	struct v4l2_ctrl *ctrl;
> +	int ret;
> +
> +	v4l2_ctrl_handler_init(hdl, 25);
> +
> +	/* Horizontal & vertical flips modify bayer code on RGB variant */
> +	sensor->hflip_ctrl =
> +		v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HFLIP, 0, 1, 1, 0);
> +	if (sensor->hflip_ctrl)
> +		sensor->hflip_ctrl->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;
> +
> +	sensor->vflip_ctrl =
> +		v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VFLIP, 0, 1, 1, 0);
> +	if (sensor->vflip_ctrl)
> +		sensor->vflip_ctrl->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;
> +
> +	sensor->patgen_ctrl =
> +		v4l2_ctrl_new_std_menu_items(hdl, ops, V4L2_CID_TEST_PATTERN,
> +					     ARRAY_SIZE(vd56g3_tp_menu) - 1, 0,
> +					     0, vd56g3_tp_menu);
> +
> +	ctrl = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
> +				      ARRAY_SIZE(vd56g3_link_freq_1lane) - 1, 0,
> +				      (sensor->nb_of_lane == 2) ?
> +					      vd56g3_link_freq_2lanes :
> +					      vd56g3_link_freq_1lane);
> +	if (ctrl)
> +		ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> +	ctrl = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_PIXEL_RATE,
> +				 sensor->pixel_clock, sensor->pixel_clock, 1,
> +				 sensor->pixel_clock);
> +	if (ctrl)
> +		ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> +	sensor->ae_ctrl = v4l2_ctrl_new_std_menu(hdl, ops,
> +						 V4L2_CID_EXPOSURE_AUTO,
> +						 V4L2_EXPOSURE_MANUAL, 0,
> +						 V4L2_EXPOSURE_AUTO);
> +
> +	sensor->ae_lock_ctrl = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_3A_LOCK, 0,
> +						 GENMASK(2, 0), 0, 0);
> +
> +	sensor->ae_bias_ctrl =
> +		v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_AUTO_EXPOSURE_BIAS,
> +				       ARRAY_SIZE(vd56g3_ev_bias_qmenu) - 1,
> +				       ARRAY_SIZE(vd56g3_ev_bias_qmenu) / 2,
> +				       vd56g3_ev_bias_qmenu);
> +
> +	/*
> +	 * Analog gain [1, 8] is computed with the following logic :
> +	 * 32/(32 - again_reg), with again_reg in the range [0:28]
> +	 * Digital gain [1.00, 8.00] is coded as a Fixed Point 5.8
> +	 */
> +	sensor->again_ctrl = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_ANALOGUE_GAIN,
> +					       0, 28, 1, 0);
> +	sensor->dgain_ctrl = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_DIGITAL_GAIN,
> +					       0x100, 0x800, 1, 0x100);
> +
> +	/*
> +	 * Set the exposure, horizontal and vertical blanking ctrls
> +	 * to hardcoded values, they will be updated in vd56g3_update_controls.
> +	 * Exposure being in an auto-cluster, set a significant value here.
> +	 */
> +	sensor->expo_ctrl = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
> +					      VD56G3_EXPOSURE_DEFAULT,
> +					      VD56G3_EXPOSURE_DEFAULT, 1,
> +					      VD56G3_EXPOSURE_DEFAULT);
> +	sensor->hblank_ctrl =
> +		v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HBLANK, 1, 1, 1, 1);
> +	if (sensor->hblank_ctrl)
> +		sensor->hblank_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +	sensor->vblank_ctrl =
> +		v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VBLANK, 1, 1, 1, 1);
> +
> +	/* Additional control based on device tree properties */
> +	if (sensor->ext_leds_mask)
> +		sensor->led_ctrl =
> +			v4l2_ctrl_new_std_menu(hdl, ops,
> +					       V4L2_CID_FLASH_LED_MODE,
> +					       V4L2_FLASH_LED_MODE_FLASH, 0,
> +					       V4L2_FLASH_LED_MODE_NONE);
> +
> +	if (hdl->error) {
> +		ret = hdl->error;
> +		goto free_ctrls;
> +	}
> +
> +	v4l2_ctrl_cluster(2, &sensor->hflip_ctrl);
> +	v4l2_ctrl_auto_cluster(4, &sensor->ae_ctrl, V4L2_EXPOSURE_MANUAL, true);
> +
> +	sensor->sd.ctrl_handler = hdl;
> +
> +	return 0;
> +
> +free_ctrls:
> +	v4l2_ctrl_handler_free(hdl);
> +
> +	return ret;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Videos ops
> + */
> +
> +static int vd56g3_stream_on(struct vd56g3 *sensor,
> +			    struct v4l2_subdev_state *state)
> +{
> +	const struct v4l2_mbus_framefmt *format;
> +	const struct v4l2_rect *crop;
> +	unsigned int csi_mbps = ((sensor->nb_of_lane == 2) ?
> +					 VD56G3_LINK_FREQ_DEF_2LANES :
> +					 VD56G3_LINK_FREQ_DEF_1LANE) * 2 / MEGA;
> +	unsigned int binning;
> +	int ret = 0;
> +
> +	format = v4l2_subdev_state_get_format(state, 0);
> +	crop = v4l2_subdev_state_get_crop(state, 0);

You could do the assignments in variable declaration.

> +
> +	/* configure clocks */
> +	cci_write(sensor->regmap, VD56G3_REG_EXT_CLOCK, sensor->xclk_freq,
> +		  &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_CLK_PLL_PREDIV, sensor->pll_prediv,
> +		  &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_CLK_SYS_PLL_MULT, sensor->pll_mult,
> +		  &ret);
> +
> +	/* configure output */
> +	cci_write(sensor->regmap, VD56G3_REG_FORMAT_CTRL,
> +		  vd56g3_get_bpp(format->code), &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OIF_CTRL, sensor->oif_ctrl, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OIF_CSI_BITRATE, csi_mbps, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OIF_IMG_CTRL,
> +		  vd56g3_get_datatype(format->code), &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_ISL_ENABLE, 0, &ret);
> +
> +	/* configure binning mode */
> +	switch (crop->width / format->width) {
> +	case 1:
> +	default:
> +		binning = READOUT_NORMAL;
> +		break;
> +	case 2:
> +		binning = READOUT_DIGITAL_BINNING_X2;
> +		break;
> +	}
> +	cci_write(sensor->regmap, VD56G3_REG_READOUT_CTRL, binning, &ret);
> +
> +	/* configure ROIs */
> +	cci_write(sensor->regmap, VD56G3_REG_Y_START, crop->top, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_Y_END,
> +		  crop->top + crop->height - 1, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OUT_ROI_X_START, crop->left, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OUT_ROI_X_END,
> +		  crop->left + crop->width - 1, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OUT_ROI_Y_START, 0, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_OUT_ROI_Y_END, crop->height - 1,
> +		  &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_AE_ROI_START_H, crop->left, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_AE_ROI_END_H,
> +		  crop->left + crop->width - 1, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_AE_ROI_START_V, 0, &ret);
> +	cci_write(sensor->regmap, VD56G3_REG_AE_ROI_END_V, crop->height - 1,
> +		  &ret);
> +	if (ret)
> +		return ret;
> +
> +	/* Setup default GPIO values; could be overridden by V4L2 ctrl setup */
> +	ret = vd56g3_write_gpiox(sensor, GENMASK(VD56G3_NB_GPIOS - 1, 0));
> +	if (ret)
> +		return ret;
> +
> +	/* Apply settings from V4L2 ctrls */
> +	ret = __v4l2_ctrl_handler_setup(&sensor->ctrl_handler);
> +	if (ret)
> +		return ret;
> +
> +	/* start streaming */
> +	cci_write(sensor->regmap, VD56G3_REG_STBY, VD56G3_CMD_START_STREAM,
> +		  &ret);
> +	vd56g3_poll_reg(sensor, VD56G3_REG_STBY, VD56G3_CMD_ACK, &ret);
> +	vd56g3_wait_state(sensor, VD56G3_SYSTEM_FSM_STREAMING, &ret);
> +
> +	return ret;
> +}
> +
> +static int vd56g3_stream_off(struct vd56g3 *sensor)
> +{
> +	int ret;
> +
> +	/* Retrieve Expo cluster to enable coldstart of AE */
> +	ret = vd56g3_read_expo_cluster(sensor, true);
> +
> +	cci_write(sensor->regmap, VD56G3_REG_STREAMING, VD56G3_CMD_STOP_STREAM,
> +		  &ret);
> +	vd56g3_poll_reg(sensor, VD56G3_REG_STREAMING, VD56G3_CMD_ACK, &ret);
> +	vd56g3_wait_state(sensor, VD56G3_SYSTEM_FSM_SW_STBY, &ret);
> +
> +	return ret;
> +}
> +
> +static int vd56g3_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +	struct i2c_client *client = v4l2_get_subdevdata(sd);
> +	struct v4l2_subdev_state *state;
> +	int ret = 0;
> +
> +	state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> +	if (enable) {
> +		ret = pm_runtime_resume_and_get(&client->dev);
> +		if (ret < 0)
> +			goto unlock;
> +		ret = vd56g3_stream_on(sensor, state);
> +		if (ret) {
> +			dev_err(&client->dev, "Failed to start streaming\n");
> +			pm_runtime_put_sync(&client->dev);
> +		}
> +	} else {
> +		vd56g3_stream_off(sensor);
> +		pm_runtime_mark_last_busy(&client->dev);
> +		pm_runtime_put_autosuspend(&client->dev);
> +	}
> +
> +	if (!ret) {
> +		sensor->streaming = enable;
> +
> +		/* some controls are locked during streaming */
> +		__v4l2_ctrl_grab(sensor->hflip_ctrl, enable);
> +		__v4l2_ctrl_grab(sensor->vflip_ctrl, enable);
> +		__v4l2_ctrl_grab(sensor->patgen_ctrl, enable);
> +	}
> +
> +unlock:
> +	v4l2_subdev_unlock_state(state);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_subdev_video_ops vd56g3_video_ops = {
> +	.s_stream = vd56g3_s_stream,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Pad ops
> + */
> +
> +/* Media bus code is dependent of :
> + *      - 8bits or 10bits output
> + *      - variant : Mono or RGB
> + *      - H/V flips parameters in case of RGB
> + */
> +static u32 vd56g3_get_mbus_code(struct vd56g3 *sensor, u32 code)
> +{
> +	unsigned int i_bpp;
> +	unsigned int j;
> +
> +	for (i_bpp = 0; i_bpp < ARRAY_SIZE(vd56g3_mbus_codes); i_bpp++) {
> +		for (j = 0; j < ARRAY_SIZE(vd56g3_mbus_codes[i_bpp]); j++) {
> +			if (vd56g3_mbus_codes[i_bpp][j] == code)
> +				goto endloops;
> +		}
> +	}
> +
> +endloops:
> +	if (i_bpp >= ARRAY_SIZE(vd56g3_mbus_codes))
> +		i_bpp = 0;
> +
> +	if (sensor->is_mono)
> +		j = 0;
> +	else
> +		j = 1 + (sensor->hflip_ctrl->val ? 1 : 0) +
> +		    (sensor->vflip_ctrl->val ? 2 : 0);
> +
> +	return vd56g3_mbus_codes[i_bpp][j];
> +}
> +
> +static int vd56g3_enum_mbus_code(struct v4l2_subdev *sd,
> +				 struct v4l2_subdev_state *sd_state,
> +				 struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +
> +	if (code->index >= ARRAY_SIZE(vd56g3_mbus_codes))
> +		return -EINVAL;
> +
> +	code->code =
> +		vd56g3_get_mbus_code(sensor, vd56g3_mbus_codes[code->index][0]);
> +
> +	return 0;
> +}
> +
> +static int vd56g3_enum_frame_size(struct v4l2_subdev *sd,
> +				  struct v4l2_subdev_state *sd_state,
> +				  struct v4l2_subdev_frame_size_enum *fse)
> +{
> +	if (fse->index >= ARRAY_SIZE(vd56g3_supported_modes))
> +		return -EINVAL;
> +
> +	fse->min_width = vd56g3_supported_modes[fse->index].width;
> +	fse->max_width = fse->min_width;
> +	fse->min_height = vd56g3_supported_modes[fse->index].height;
> +	fse->max_height = fse->min_height;
> +
> +	return 0;
> +}
> +
> +static void vd56g3_update_img_pad_format(struct vd56g3 *sensor,
> +					 const struct vd56g3_mode *mode,
> +					 u32 mbus_code,
> +					 struct v4l2_mbus_framefmt *mbus_fmt)
> +{
> +	mbus_fmt->width = mode->width;
> +	mbus_fmt->height = mode->height;
> +	mbus_fmt->code = vd56g3_get_mbus_code(sensor, mbus_code);
> +	mbus_fmt->colorspace = V4L2_COLORSPACE_RAW;
> +	mbus_fmt->field = V4L2_FIELD_NONE;
> +	mbus_fmt->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
> +	mbus_fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> +	mbus_fmt->xfer_func = V4L2_XFER_FUNC_NONE;
> +}
> +
> +static int vd56g3_set_pad_fmt(struct v4l2_subdev *sd,
> +			      struct v4l2_subdev_state *sd_state,
> +			      struct v4l2_subdev_format *sd_fmt)
> +{
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +	const struct vd56g3_mode *new_mode;
> +	struct v4l2_rect pad_crop;
> +	unsigned int binning;
> +	int ret = 0;
> +
> +	if (sensor->streaming)
> +		return -EBUSY;

Setting the try format should be possible during streaming.

> +
> +	new_mode = v4l2_find_nearest_size(vd56g3_supported_modes,
> +					  ARRAY_SIZE(vd56g3_supported_modes),
> +					  width, height, sd_fmt->format.width,
> +					  sd_fmt->format.height);
> +
> +	vd56g3_update_img_pad_format(sensor, new_mode, sd_fmt->format.code,
> +				     &sd_fmt->format);
> +
> +	/* Compute crop rectangle (maximized via binning) */
> +	binning = min(VD56G3_NATIVE_WIDTH / sd_fmt->format.width,
> +		      VD56G3_NATIVE_HEIGHT / sd_fmt->format.height);
> +	binning = min(binning, 2U);
> +	pad_crop.width = sd_fmt->format.width * binning;
> +	pad_crop.height = sd_fmt->format.height * binning;
> +	pad_crop.left = (VD56G3_NATIVE_WIDTH - pad_crop.width) / 2;
> +	pad_crop.top = (VD56G3_NATIVE_HEIGHT - pad_crop.height) / 2;
> +
> +	/* Update active state's format and crop */
> +	if (sd_fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> +		ret = vd56g3_update_controls(sensor);
> +
> +	if (!ret) {
> +		*v4l2_subdev_state_get_format(sd_state, sd_fmt->pad) =
> +			sd_fmt->format;
> +		*v4l2_subdev_state_get_crop(sd_state, sd_fmt->pad) = pad_crop;
> +	}
> +
> +	return ret;
> +}
> +
> +static int vd56g3_get_selection(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *sd_state,
> +				struct v4l2_subdev_selection *sel)
> +{
> +	switch (sel->target) {
> +	case V4L2_SEL_TGT_CROP:
> +		sel->r = *v4l2_subdev_state_get_crop(sd_state, 0);
> +		break;
> +	case V4L2_SEL_TGT_NATIVE_SIZE:
> +	case V4L2_SEL_TGT_CROP_DEFAULT:
> +	case V4L2_SEL_TGT_CROP_BOUNDS:
> +		sel->r.top = 0;
> +		sel->r.left = 0;
> +		sel->r.width = VD56G3_NATIVE_WIDTH;
> +		sel->r.height = VD56G3_NATIVE_HEIGHT;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int vd56g3_init_state(struct v4l2_subdev *sd,
> +			     struct v4l2_subdev_state *sd_state)
> +{
> +	unsigned int def_mode = VD56G3_DEFAULT_MODE;
> +	struct v4l2_subdev_format fmt = {
> +		.which = V4L2_SUBDEV_FORMAT_TRY,
> +		.pad = 0,
> +		.format = {
> +			.code = vd56g3_mbus_codes[0][0],
> +			.width = vd56g3_supported_modes[def_mode].width,
> +			.height = vd56g3_supported_modes[def_mode].height,
> +		},
> +	};
> +
> +	vd56g3_set_pad_fmt(sd, sd_state, &fmt);

I think you could just return what vd56g3_set_pad_fmt did -- it's zero
(after fixing the streaming check in it).

> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_core_ops vd56g3_core_ops = {
> +	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
> +	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
> +};
> +
> +static const struct v4l2_subdev_pad_ops vd56g3_pad_ops = {
> +	.enum_mbus_code = vd56g3_enum_mbus_code,
> +	.enum_frame_size = vd56g3_enum_frame_size,
> +	.get_fmt = v4l2_subdev_get_fmt,
> +	.set_fmt = vd56g3_set_pad_fmt,
> +	.get_selection = vd56g3_get_selection,
> +};
> +
> +static const struct v4l2_subdev_ops vd56g3_subdev_ops = {
> +	.core = &vd56g3_core_ops,
> +	.video = &vd56g3_video_ops,
> +	.pad = &vd56g3_pad_ops,
> +};
> +
> +static const struct media_entity_operations vd56g3_subdev_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static const struct v4l2_subdev_internal_ops vd56g3_internal_ops = {
> +	.init_state = vd56g3_init_state,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Power management
> + */
> +
> +static int vd56g3_power_on(struct vd56g3 *sensor)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	int ret;
> +
> +	/* power on */
> +	ret = regulator_bulk_enable(ARRAY_SIZE(sensor->supplies),
> +				    sensor->supplies);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to enable regulators %d", ret);
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(sensor->xclk);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to enable clock %d", ret);
> +		goto disable_reg;
> +	}
> +
> +	gpiod_set_value_cansleep(sensor->reset_gpio, 0);
> +	usleep_range(3500, 4000);
> +	ret = vd56g3_wait_state(sensor, VD56G3_SYSTEM_FSM_READY_TO_BOOT, NULL);
> +	if (ret) {
> +		dev_err(&client->dev, "Sensor reset failed %d\n", ret);
> +		goto disable_clock;
> +	}
> +
> +	/* boot sensor */
> +	cci_write(sensor->regmap, VD56G3_REG_BOOT, VD56G3_CMD_BOOT, &ret);
> +	vd56g3_poll_reg(sensor, VD56G3_REG_BOOT, VD56G3_CMD_ACK, &ret);
> +	vd56g3_wait_state(sensor, VD56G3_SYSTEM_FSM_SW_STBY, &ret);
> +	if (ret) {
> +		dev_err(&client->dev, "sensor boot failed %d", ret);
> +		goto disable_clock;
> +	}
> +
> +	return 0;
> +
> +disable_clock:
> +	clk_disable_unprepare(sensor->xclk);
> +	gpiod_set_value_cansleep(sensor->reset_gpio, 1);
> +disable_reg:
> +	regulator_bulk_disable(ARRAY_SIZE(sensor->supplies), sensor->supplies);
> +
> +	return ret;
> +}
> +
> +static int vd56g3_power_off(struct vd56g3 *sensor)
> +{
> +	clk_disable_unprepare(sensor->xclk);
> +	gpiod_set_value_cansleep(sensor->reset_gpio, 1);
> +	regulator_bulk_disable(ARRAY_SIZE(sensor->supplies), sensor->supplies);
> +	return 0;

You can make the return type void.

Do you need two pairs of functions doing the same, or could you call
vd56g3_runtime_resume and vd56g3_runtime_suspend from driver's probe and
remove functions, too?

> +}
> +
> +static int vd56g3_runtime_resume(struct device *dev)
> +{
> +	struct v4l2_subdev *sd = dev_get_drvdata(dev);
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +	struct i2c_client *client = sensor->i2c_client;
> +	int ret;
> +
> +	ret = vd56g3_power_on(sensor);
> +	if (ret)
> +		dev_err(&client->dev, "Failed to power on %d", ret);

You seem to be printing more precise messages in vd56g3_power_on() already.

> +
> +	return ret;
> +}
> +
> +static int vd56g3_runtime_suspend(struct device *dev)
> +{
> +	struct v4l2_subdev *sd = dev_get_drvdata(dev);
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +
> +	return vd56g3_power_off(sensor);
> +}
> +
> +static const struct dev_pm_ops vd56g3_pm_ops = {
> +	SET_RUNTIME_PM_OPS(vd56g3_runtime_suspend, vd56g3_runtime_resume, NULL)
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Probe and initialization
> + */
> +
> +static int vd56g3_check_csi_conf(struct vd56g3 *sensor,
> +				 struct fwnode_handle *endpoint)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct v4l2_fwnode_endpoint ep = { .bus_type = V4L2_MBUS_CSI2_DPHY };
> +	u32 phy_data_lanes[VD56G3_MAX_CSI_DATA_LANES] = { ~0, ~0 };
> +	u8 n_lanes;
> +	u64 frequency;
> +	int p, l;
> +	int ret = 0;
> +
> +	ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &ep);
> +	if (ret)
> +		return -EINVAL;
> +
> +	/* Check lanes number */
> +	n_lanes = ep.bus.mipi_csi2.num_data_lanes;
> +	if (n_lanes != 1 && n_lanes != 2) {
> +		dev_err(&client->dev, "Invalid data lane number %d\n", n_lanes);
> +		ret = -EINVAL;
> +		goto done;
> +	}
> +	sensor->nb_of_lane = n_lanes;
> +
> +	/* Clock lane must be first */
> +	if (ep.bus.mipi_csi2.clock_lane != 0) {
> +		dev_err(&client->dev, "Clk lane must be mapped to lane 0\n");
> +		ret = -EINVAL;
> +		goto done;
> +	}
> +
> +	/* Prepare Output Interface conf based on lane settings

/*
 * Multi-line
 * comment.
 */

> +	 * logical to physical lane conversion (+ pad remaining slots)
> +	 */
> +	for (l = 0; l < n_lanes; l++)
> +		phy_data_lanes[ep.bus.mipi_csi2.data_lanes[l] - 1] = l;
> +	for (p = 0; p < VD56G3_MAX_CSI_DATA_LANES; p++) {
> +		if (phy_data_lanes[p] != ~0)
> +			continue;
> +		phy_data_lanes[p] = l;
> +		l++;
> +	}
> +	sensor->oif_ctrl = n_lanes |
> +			   (ep.bus.mipi_csi2.lane_polarities[0] << 3) |
> +			   ((phy_data_lanes[0]) << 4) |
> +			   (ep.bus.mipi_csi2.lane_polarities[1] << 6) |
> +			   ((phy_data_lanes[1]) << 7) |
> +			   (ep.bus.mipi_csi2.lane_polarities[2] << 9);
> +
> +	/* Check link frequency */
> +	if (!ep.nr_of_link_frequencies) {
> +		dev_err(&client->dev, "link-frequency not found in DT\n");
> +		ret = -EINVAL;
> +		goto done;
> +	}
> +	frequency = (n_lanes == 2) ? VD56G3_LINK_FREQ_DEF_2LANES :
> +				     VD56G3_LINK_FREQ_DEF_1LANE;
> +	if (ep.nr_of_link_frequencies != 1 ||
> +	    ep.link_frequencies[0] != frequency) {
> +		dev_err(&client->dev, "Link frequency not supported: %lld\n",
> +			ep.link_frequencies[0]);
> +		ret = -EINVAL;
> +		goto done;
> +	}
> +
> +done:
> +	v4l2_fwnode_endpoint_free(&ep);
> +	return ret;
> +}
> +
> +static int vd56g3_parse_dt_gpios_array(struct vd56g3 *sensor, char *prop_name,
> +				       u32 *array, int *nb)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct device_node *np = client->dev.of_node;
> +	unsigned int i;
> +
> +	*nb = of_property_read_variable_u32_array(np, prop_name, array, 0,
> +						  VD56G3_NB_GPIOS);
> +
> +	if (*nb == -EINVAL) {
> +		*nb = 0;
> +		return *nb;
> +	} else if (*nb < 0) {
> +		dev_err(&client->dev, "Failed to read %s prop\n", prop_name);
> +		return *nb;
> +	}
> +
> +	for (i = 0; i < *nb; i++) {
> +		if (array[i] >= VD56G3_NB_GPIOS) {
> +			dev_err(&client->dev, "Invalid GPIO : %d\n", array[i]);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int vd56g3_parse_dt_gpios(struct vd56g3 *sensor)
> +{
> +	u32 led_gpios[VD56G3_NB_GPIOS];
> +	int nb_gpios_leds;
> +	unsigned int i;
> +	int ret;
> +
> +	/* Initialize GPIOs to default */
> +	for (i = 0; i < VD56G3_NB_GPIOS; i++)
> +		sensor->gpios[i] = VD56G3_GPIOX_GPIO_IN;
> +	sensor->ext_leds_mask = 0;
> +
> +	/* Take into account optional 'st,leds' output for GPIOs */
> +	ret = vd56g3_parse_dt_gpios_array(sensor, "st,leds", led_gpios,
> +					  &nb_gpios_leds);
> +	if (ret)
> +		return ret;
> +	for (i = 0; i < nb_gpios_leds; i++) {
> +		sensor->gpios[led_gpios[i]] = VD56G3_GPIOX_STROBE_MODE;
> +		set_bit(led_gpios[i], &sensor->ext_leds_mask);
> +	}
> +
> +	return 0;
> +}
> +
> +static int vd56g3_parse_dt(struct vd56g3 *sensor)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct device *dev = &client->dev;
> +	struct fwnode_handle *endpoint;
> +	int ret;
> +
> +	endpoint = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
> +	if (!endpoint) {
> +		dev_err(dev, "endpoint node not found\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = vd56g3_check_csi_conf(sensor, endpoint);
> +	fwnode_handle_put(endpoint);
> +	if (ret)
> +		return ret;
> +
> +	return vd56g3_parse_dt_gpios(sensor);
> +}
> +
> +static int vd56g3_get_regulators(struct vd56g3 *sensor)
> +{
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(sensor->supplies); i++)
> +		sensor->supplies[i].supply = vd56g3_supply_names[i];
> +
> +	return devm_regulator_bulk_get(&sensor->i2c_client->dev,
> +				       ARRAY_SIZE(sensor->supplies),
> +				       sensor->supplies);
> +}
> +
> +static int vd56g3_prepare_clock_tree(struct vd56g3 *sensor)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	const unsigned int predivs[] = { 1, 2, 4 };
> +	u32 pll_out;
> +	int i;
> +
> +	/* External clock must be in [6Mhz-27Mhz] */
> +	if (sensor->xclk_freq < 6 * HZ_PER_MHZ ||
> +	    sensor->xclk_freq > 27 * HZ_PER_MHZ) {
> +		dev_err(&client->dev,
> +			"Only 6Mhz-27Mhz clock range supported. Provided %lu MHz\n",
> +			sensor->xclk_freq / HZ_PER_MHZ);
> +		return -EINVAL;
> +	}
> +
> +	/* PLL input should be in [6Mhz-12Mhz[ */
> +	for (i = 0; i < ARRAY_SIZE(predivs); i++) {
> +		sensor->pll_prediv = predivs[i];
> +		if (sensor->xclk_freq / sensor->pll_prediv < 12 * HZ_PER_MHZ)
> +			break;
> +	}
> +
> +	/* PLL output clock must be as close as possible to 804Mhz */
> +	sensor->pll_mult = (VD56G3_TARGET_PLL * sensor->pll_prediv +
> +			    sensor->xclk_freq / 2) /
> +			   sensor->xclk_freq;
> +	pll_out = sensor->xclk_freq * sensor->pll_mult / sensor->pll_prediv;
> +
> +	/* Target Pixel Clock for standard 10bit ADC mode : 160.8Mhz */
> +	sensor->pixel_clock = pll_out / VD56G3_VT_CLOCK_DIV;
> +
> +	return 0;
> +}
> +
> +static int vd56g3_detect(struct vd56g3 *sensor)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct device *dev = &client->dev;
> +	unsigned int model;
> +	u64 model_id = 0;
> +	u64 device_revision = 0;
> +	u64 optical_revision = 0;
> +	int ret = 0;
> +
> +	model = (uintptr_t)device_get_match_data(dev);
> +
> +	cci_read(sensor->regmap, VD56G3_REG_MODEL_ID, &model_id, &ret);
> +	if (ret)
> +		return ret;

As you're calling cci_read() and then checking ret, I'd assing ret here the
usual way (and below, too).

> +
> +	if (model_id != VD56G3_MODEL_ID) {
> +		dev_err(&client->dev, "Unsupported sensor id %x",
> +			(u16)model_id);
> +		return -ENODEV;
> +	}
> +
> +	cci_read(sensor->regmap, VD56G3_REG_REVISION, &device_revision, &ret);
> +	if (ret)
> +		return ret;
> +
> +	if ((device_revision >> 8) != VD56G3_REVISION_CUT3) {
> +		dev_err(&client->dev, "Unsupported Cut version %x",
> +			(u16)device_revision);
> +		return -ENODEV;
> +	}
> +
> +	cci_read(sensor->regmap, VD56G3_REG_OPTICAL_REVISION, &optical_revision,
> +		 &ret);
> +	if (ret)
> +		return ret;
> +
> +	sensor->is_mono =
> +		((optical_revision & 1) == VD56G3_OPTICAL_REVISION_MONO);
> +	if ((sensor->is_mono && model == VD56G3_MODEL_VD66GY) ||
> +	    (!sensor->is_mono && model == VD56G3_MODEL_VD56G3)) {
> +		dev_err(&client->dev,
> +			"Found %s sensor, while %s model is defined in DT",
> +			(sensor->is_mono) ? "Mono" : "Bayer",
> +			(model == VD56G3_MODEL_VD56G3) ? "vd56g3" : "vd66gy");
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int vd56g3_subdev_init(struct vd56g3 *sensor)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	int ret;
> +
> +	/* Init sub device */
> +	v4l2_i2c_subdev_init(&sensor->sd, client, &vd56g3_subdev_ops);
> +	sensor->sd.internal_ops = &vd56g3_internal_ops;
> +	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> +	sensor->sd.entity.ops = &vd56g3_subdev_entity_ops;
> +
> +	/* Init source pad */
> +	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
> +	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> +	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to init media entity : %d", ret);
> +		return ret;
> +	}
> +
> +	/* Init controls */
> +	ret = vd56g3_init_controls(sensor);
> +	if (ret) {
> +		dev_err(&client->dev, "Controls initialization failed %d", ret);
> +		goto err_media;
> +	}
> +
> +	/* Init vd56g3 struct : default resolution + raw8 */
> +	sensor->sd.state_lock = sensor->ctrl_handler.lock;
> +	ret = v4l2_subdev_init_finalize(&sensor->sd);
> +	if (ret) {
> +		dev_err(&client->dev, "subdev init error: %d", ret);
> +		goto err_ctrls;
> +	}
> +
> +	return vd56g3_update_controls(sensor);
> +
> +err_ctrls:
> +	v4l2_ctrl_handler_free(sensor->sd.ctrl_handler);
> +
> +err_media:
> +	media_entity_cleanup(&sensor->sd.entity);

Newline here?

> +	return ret;
> +}
> +
> +static void vd56g3_subdev_cleanup(struct vd56g3 *sensor)
> +{
> +	v4l2_async_unregister_subdev(&sensor->sd);
> +	v4l2_subdev_cleanup(&sensor->sd);
> +	media_entity_cleanup(&sensor->sd.entity);
> +	v4l2_ctrl_handler_free(sensor->sd.ctrl_handler);
> +}
> +
> +static int vd56g3_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct vd56g3 *sensor;
> +	int ret;
> +
> +	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
> +	if (!sensor)
> +		return -ENOMEM;
> +
> +	sensor->i2c_client = client;
> +
> +	ret = vd56g3_parse_dt(sensor);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to parse Device Tree.");
> +
> +	/* Get (and check) resources : power regs, ext clock, reset gpio */
> +	ret = vd56g3_get_regulators(sensor);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to get regulators.");
> +
> +	sensor->xclk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(sensor->xclk))
> +		return dev_err_probe(dev, PTR_ERR(sensor->xclk),
> +				     "Failed to get xclk.");
> +	sensor->xclk_freq = clk_get_rate(sensor->xclk);
> +	ret = vd56g3_prepare_clock_tree(sensor);
> +	if (ret)
> +		return ret;
> +
> +	sensor->reset_gpio =
> +		devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(sensor->reset_gpio))
> +		return dev_err_probe(dev, PTR_ERR(sensor->reset_gpio),
> +				     "Failed to get reset gpio.");
> +
> +	sensor->regmap = devm_cci_regmap_init_i2c(client, 16);
> +	if (IS_ERR(sensor->regmap))
> +		return dev_err_probe(dev, PTR_ERR(sensor->regmap),
> +				     "Failed to init regmap.");
> +
> +	/* Power ON */
> +	ret = vd56g3_power_on(sensor);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Sensor power on failed.");
> +
> +	/* Enable PM runtime with autosuspend (sensor being ON, set active) */
> +	pm_runtime_set_active(dev);
> +	pm_runtime_get_noresume(dev);
> +	pm_runtime_enable(dev);
> +	pm_runtime_set_autosuspend_delay(dev, 1000);
> +	pm_runtime_use_autosuspend(dev);
> +
> +	/* Check HW model/version */
> +	ret = vd56g3_detect(sensor);
> +	if (ret) {
> +		dev_err(&client->dev, "Sensor detect failed : %d", ret);
> +		goto err_power_off;
> +	}
> +
> +	/* Initialize, then register V4L2 subdev */
> +	ret = vd56g3_subdev_init(sensor);
> +	if (ret) {
> +		dev_err(&client->dev, "V4l2 init failed : %d", ret);
> +		goto err_power_off;
> +	}
> +
> +	ret = v4l2_async_register_subdev(&sensor->sd);
> +	if (ret) {
> +		dev_err(&client->dev, "async subdev register failed %d", ret);
> +		goto err_subdev;
> +	}
> +
> +	/* Sensor could now be powered off (after the autosuspend delay) */
> +	pm_runtime_mark_last_busy(dev);
> +	pm_runtime_put_autosuspend(dev);
> +
> +	dev_dbg(&client->dev, "Successfully probe %s sensor",
> +		(sensor->is_mono) ? "vd56g3" : "vd66gy");
> +
> +	return 0;
> +
> +err_subdev:
> +	vd56g3_subdev_cleanup(sensor);
> +err_power_off:
> +	pm_runtime_disable(dev);
> +	pm_runtime_put_noidle(dev);
> +	vd56g3_power_off(sensor);

A newline here?

> +	return ret;
> +}
> +
> +static void vd56g3_remove(struct i2c_client *client)
> +{
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct vd56g3 *sensor = to_vd56g3(sd);
> +
> +	vd56g3_subdev_cleanup(sensor);
> +
> +	pm_runtime_disable(&client->dev);
> +	if (!pm_runtime_status_suspended(&client->dev))
> +		vd56g3_power_off(sensor);
> +	pm_runtime_set_suspended(&client->dev);
> +}
> +
> +static const struct of_device_id vd56g3_dt_ids[] = {
> +	{ .compatible = "st,st-vd56g3", .data = (void *)VD56G3_MODEL_VD56G3 },
> +	{ .compatible = "st,st-vd66gy", .data = (void *)VD56G3_MODEL_VD66GY },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, vd56g3_dt_ids);
> +
> +static struct i2c_driver vd56g3_i2c_driver = {
> +	.driver = {
> +		.name  = "st-vd56g3",
> +		.of_match_table = vd56g3_dt_ids,
> +		.pm = &vd56g3_pm_ops,
> +	},
> +	.probe = vd56g3_probe,
> +	.remove = vd56g3_remove,
> +};
> +
> +module_i2c_driver(vd56g3_i2c_driver);
> +
> +MODULE_AUTHOR("Benjamin Mugnier <benjamin.mugnier@foss.st.com>");
> +MODULE_AUTHOR("Mickael Guene <mickael.guene@st.com>");
> +MODULE_AUTHOR("Sylvain Petinot <sylvain.petinot@foss.st.com>");
> +MODULE_DESCRIPTION("ST VD56G3 sensor driver");
> +MODULE_LICENSE("GPL");