Re: [PATCH v4 3/3] media: i2c: imx471: Add Sony IMX471 image sensor driver

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Kate,

Thanks for the update. I think we're nearly there.

Please also run

	$ ./scripts/checkpatch.pl --strict --max-line-length=80

on this.

Also see my commens below...

On Tue, Jun 09, 2026 at 08:49:26PM +0800, Kate Hsuan wrote:
> Add a new driver for Sony imx471 camera sensor. It is based on
> Jimmy Su <jimmy.su@intel.com> implementation and the driver can be found
> in the following URL.
> https://github.com/intel/ipu6-drivers/commits/master/drivers/media/i2c/imx471.c
> 
> This sensor can be found on Lenovo X1 Carbon G14, X9-14 and X9-15 laptops
> and it is a part of IPU7 solution. The driver was tested on Lenovo X1
> Carbon G14, X9-14 and X9-15 laptops.
> 
> Signed-off-by: Kate Hsuan <hpa@redhat.com>
> ---
>  MAINTAINERS                |   6 +
>  drivers/media/i2c/Kconfig  |  10 +
>  drivers/media/i2c/Makefile |   1 +
>  drivers/media/i2c/imx471.c | 949 +++++++++++++++++++++++++++++++++++++
>  4 files changed, 966 insertions(+)
>  create mode 100644 drivers/media/i2c/imx471.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 9ec290e38b44..f4bb6b528fa1 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -24963,6 +24963,12 @@ T:	git git://linuxtv.org/media.git
>  F:	Documentation/devicetree/bindings/media/i2c/sony,imx415.yaml
>  F:	drivers/media/i2c/imx415.c
>  
> +SONY IMX471 SENSOR DRIVER
> +M:	Kate Hsuan <hpa@redhat.com>
> +L:	linux-media@vger.kernel.org
> +S:	Maintained
> +F:	drivers/media/i2c/imx471.c
> +
>  SONY MEMORYSTICK SUBSYSTEM
>  M:	Maxim Levitsky <maximlevitsky@gmail.com>
>  M:	Alex Dubov <oakad@yahoo.com>
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 8f2ba4121586..e1143579ae3d 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -287,6 +287,16 @@ config VIDEO_IMX415
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called imx415.
>  
> +config VIDEO_IMX471
> +	tristate "Sony IMX471 sensor support"
> +	select V4L2_CCI_I2C
> +	help
> +	  This is a Video4Linux2 sensor driver for the Sony
> +	  IMX471 camera.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called imx471.
> +
>  config VIDEO_MAX9271_LIB
>  	tristate
>  
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index 90b276a7417a..f5c9fa93dc47 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -61,6 +61,7 @@ obj-$(CONFIG_VIDEO_IMX335) += imx335.o
>  obj-$(CONFIG_VIDEO_IMX355) += imx355.o
>  obj-$(CONFIG_VIDEO_IMX412) += imx412.o
>  obj-$(CONFIG_VIDEO_IMX415) += imx415.o
> +obj-$(CONFIG_VIDEO_IMX471) += imx471.o
>  obj-$(CONFIG_VIDEO_IR_I2C) += ir-kbd-i2c.o
>  obj-$(CONFIG_VIDEO_ISL7998X) += isl7998x.o
>  obj-$(CONFIG_VIDEO_KS0127) += ks0127.o
> diff --git a/drivers/media/i2c/imx471.c b/drivers/media/i2c/imx471.c
> new file mode 100644
> index 000000000000..4d570cf7a91d
> --- /dev/null
> +++ b/drivers/media/i2c/imx471.c
> @@ -0,0 +1,949 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * imx471.c - imx471 sensor driver
> + *
> + * Copyright (C) 2025 Intel Corporation
> + * Copyright (C) 2026 Kate Hsuan <hpa@redhat.com>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/unaligned.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>
> +
> +#define IMX471_REG_MODE_SELECT			CCI_REG8(0x0100)
> +#define IMX471_MODE_STANDBY			0x00
> +#define IMX471_MODE_STREAMING			0x01
> +
> +/* Chip ID */
> +#define IMX471_REG_CHIP_ID			CCI_REG16(0x0016)
> +#define IMX471_CHIP_ID				0x0471
> +
> +/* V_TIMING internal */
> +#define IMX471_REG_FLL				CCI_REG16(0x0340)
> +#define IMX471_FLL_MAX				0xffff
> +
> +/* Exposure control */
> +#define IMX471_REG_EXPOSURE			CCI_REG16(0x0202)
> +#define IMX471_EXPOSURE_MIN			1
> +#define IMX471_EXPOSURE_STEP			1
> +#define IMX471_EXPOSURE_DEFAULT			1270
> +
> +/* Default exposure margin */
> +#define IMX471_EXPOSURE_MARGIN			18
> +
> +/* Analog gain control */
> +#define IMX471_REG_ANALOG_GAIN			CCI_REG16(0x0204)
> +#define IMX471_ANA_GAIN_MIN			0
> +#define IMX471_ANA_GAIN_MAX			800
> +#define IMX471_ANA_GAIN_STEP			1
> +#define IMX471_ANA_GAIN_DEFAULT			0
> +
> +/* Digital gain control */
> +#define IMX471_REG_DPGA_USE_GLOBAL_GAIN		CCI_REG16(0x3ff9)
> +#define IMX471_REG_DIG_GAIN_GLOBAL		CCI_REG16(0x020e)
> +#define IMX471_DGTL_GAIN_MIN			256
> +#define IMX471_DGTL_GAIN_MAX			4095
> +#define IMX471_DGTL_GAIN_STEP			1
> +#define IMX471_DGTL_GAIN_DEFAULT		256
> +
> +/* HFLIP and VFLIP control */
> +#define IMX471_REG_ORIENTATION			CCI_REG8(0x0101)
> +#define IMX471_HFLIP_BIT			BIT(0)
> +#define IMX471_VFLIP_BIT			BIT(1)
> +
> +/* Test Pattern Control */
> +#define IMX471_REG_TEST_PATTERN			CCI_REG8(0x0600)
> +#define IMX471_TEST_PATTERN_DISABLED		0
> +#define IMX471_TEST_PATTERN_SOLID_COLOR		1
> +#define IMX471_TEST_PATTERN_COLOR_BARS		2
> +#define IMX471_TEST_PATTERN_GRAY_COLOR_BARS	3
> +#define IMX471_TEST_PATTERN_PN9			4
> +
> +/* default link frequency and external clock */
> +#define IMX471_LINK_FREQ_DEFAULT		200000000LL
> +#define IMX471_EXT_CLK				19200000
> +#define IMX471_LINK_FREQ_INDEX			0
> +
> +/* IMX471 native and active pixel array size */
> +#define IMX471_NATIVE_WIDTH			4672
> +#define IMX471_NATIVE_HEIGHT			3512
> +#define IMX471_PIXEL_ARRAY_LEFT			8
> +#define IMX471_PIXEL_ARRAY_TOP			8
> +#define IMX471_PIXEL_ARRAY_WIDTH		4656
> +#define IMX471_PIXEL_ARRAY_HEIGHT		3496
> +
> +#define IMX471_REG_EXCK_FREQ			CCI_REG16(0x0136)
> +#define IMX471_EXCK_FREQ(n)			((n) * 256)	/* n in MHz */
> +
> +#define IMX471_REG_CSI_DATA_FORMAT		CCI_REG16(0x0112)
> +#define IMX471_CSI_DATA_FORMAT_RAW10		0x0a0a
> +
> +#define IMX471_REG_CSI_LANE_MODE		CCI_REG8(0x0114)
> +#define IMX471_CSI_2_LANE_MODE			1
> +#define IMX471_CSI_4_LANE_MODE			3
> +
> +#define IMX471_REG_X_ADD_STA			CCI_REG16(0x0344)
> +#define IMX471_REG_Y_ADD_STA			CCI_REG16(0x0346)
> +#define IMX471_REG_X_ADD_END			CCI_REG16(0x0348)
> +#define IMX471_REG_Y_ADD_END			CCI_REG16(0x034a)
> +#define IMX471_REG_X_OUTPUT_SIZE		CCI_REG16(0x034c)
> +#define IMX471_REG_Y_OUTPUT_SIZE		CCI_REG16(0x034e)
> +#define IMX471_REG_X_EVEN_INC			CCI_REG8(0x0381)
> +#define IMX471_REG_X_ODD_INC			CCI_REG8(0x0383)
> +#define IMX471_REG_Y_EVEN_INC			CCI_REG8(0x0385)
> +#define IMX471_REG_Y_ODD_INC			CCI_REG8(0x0387)
> +
> +#define IMX471_REG_DIG_CROP_X_OFFSET		CCI_REG16(0x0408)
> +#define IMX471_REG_DIG_CROP_Y_OFFSET		CCI_REG16(0x040a)
> +#define IMX471_REG_DIG_CROP_WIDTH		CCI_REG16(0x040c)
> +#define IMX471_REG_DIG_CROP_HEIGHT		CCI_REG16(0x040e)
> +
> +#define to_imx471(_sd) container_of_const(_sd, struct imx471, sd)
> +
> +static const char * const imx471_supply_name[] = {
> +	"avdd",
> +};
> +
> +struct imx471_mode {
> +	u32 width;
> +	u32 height;
> +
> +	/* V-timing */
> +	u32 fll_def;
> +	u32 fll_min;
> +
> +	/* H-timing */
> +	u32 llp;
> +
> +	u32 link_freq_index;
> +
> +	const struct cci_reg_sequence *default_mode_regs;
> +	unsigned int default_mode_regs_length;
> +};
> +
> +struct imx471 {
> +	struct v4l2_subdev sd;
> +	struct media_pad pad;
> +
> +	struct v4l2_ctrl_handler ctrl_handler;
> +	struct v4l2_ctrl *pixel_rate;
> +	struct v4l2_ctrl *vblank;
> +	struct v4l2_ctrl *hblank;
> +	struct v4l2_ctrl *vflip;
> +	struct v4l2_ctrl *hflip;
> +	struct v4l2_ctrl *exposure;
> +
> +	struct gpio_desc *reset_gpio;
> +	struct regulator_bulk_data supplies[ARRAY_SIZE(imx471_supply_name)];
> +	struct clk *img_clk;
> +
> +	struct device *dev;
> +	struct regmap *regmap;
> +};
> +
> +static const struct cci_reg_sequence imx471_global_regs[] = {
> +	{ IMX471_REG_EXCK_FREQ, IMX471_EXCK_FREQ(19.2) },
> +	{ CCI_REG8(0x3c7e), 0x08 },
> +	{ CCI_REG8(0x3c7f), 0x05 },
> +	{ CCI_REG8(0x3e35), 0x00 },
> +	{ CCI_REG8(0x3e36), 0x00 },
> +	{ CCI_REG8(0x3e37), 0x00 },
> +	{ CCI_REG8(0x3f7f), 0x01 },
> +	{ CCI_REG8(0x4431), 0x04 },
> +	{ CCI_REG8(0x531c), 0x01 },
> +	{ CCI_REG8(0x531d), 0x02 },
> +	{ CCI_REG8(0x531e), 0x04 },
> +	{ CCI_REG8(0x5928), 0x00 },
> +	{ CCI_REG8(0x5929), 0x2f },
> +	{ CCI_REG8(0x592a), 0x00 },
> +	{ CCI_REG8(0x592b), 0x85 },
> +	{ CCI_REG8(0x592c), 0x00 },
> +	{ CCI_REG8(0x592d), 0x32 },
> +	{ CCI_REG8(0x592e), 0x00 },
> +	{ CCI_REG8(0x592f), 0x88 },
> +	{ CCI_REG8(0x5930), 0x00 },
> +	{ CCI_REG8(0x5931), 0x3d },
> +	{ CCI_REG8(0x5932), 0x00 },
> +	{ CCI_REG8(0x5933), 0x93 },
> +	{ CCI_REG8(0x5938), 0x00 },
> +	{ CCI_REG8(0x5939), 0x24 },
> +	{ CCI_REG8(0x593a), 0x00 },
> +	{ CCI_REG8(0x593b), 0x7a },
> +	{ CCI_REG8(0x593c), 0x00 },
> +	{ CCI_REG8(0x593d), 0x24 },
> +	{ CCI_REG8(0x593e), 0x00 },
> +	{ CCI_REG8(0x593f), 0x7a },
> +	{ CCI_REG8(0x5940), 0x00 },
> +	{ CCI_REG8(0x5941), 0x2f },
> +	{ CCI_REG8(0x5942), 0x00 },
> +	{ CCI_REG8(0x5943), 0x85 },
> +	{ CCI_REG8(0x5f0e), 0x6e },
> +	{ CCI_REG8(0x5f11), 0xc6 },
> +	{ CCI_REG8(0x5f17), 0x5e },
> +	{ CCI_REG8(0x7990), 0x01 },
> +	{ CCI_REG8(0x7993), 0x5d },
> +	{ CCI_REG8(0x7994), 0x5d },
> +	{ CCI_REG8(0x7995), 0xa1 },
> +	{ CCI_REG8(0x799a), 0x01 },
> +	{ CCI_REG8(0x799d), 0x00 },
> +	{ CCI_REG8(0x8169), 0x01 },
> +	{ CCI_REG8(0x8359), 0x01 },
> +	{ CCI_REG8(0x9302), 0x1e },
> +	{ CCI_REG8(0x9306), 0x1f },
> +	{ CCI_REG8(0x930a), 0x26 },
> +	{ CCI_REG8(0x930e), 0x23 },
> +	{ CCI_REG8(0x9312), 0x23 },
> +	{ CCI_REG8(0x9316), 0x2c },
> +	{ CCI_REG8(0x9317), 0x19 },
> +	{ CCI_REG8(0xb046), 0x01 },
> +	{ CCI_REG8(0xb048), 0x01 },
> +};
> +
> +static const struct cci_reg_sequence mode_1928x1088_regs[] = {
> +	{ IMX471_REG_X_ADD_STA, 8 },
> +	{ IMX471_REG_Y_ADD_STA, 408 },
> +	{ IMX471_REG_X_ADD_END, 4647 },
> +	{ IMX471_REG_Y_ADD_END, 3051 },
> +	{ IMX471_REG_X_EVEN_INC, 1 },
> +	{ IMX471_REG_X_ODD_INC, 1 },
> +	{ IMX471_REG_Y_EVEN_INC, 1 },
> +	{ IMX471_REG_Y_ODD_INC, 1 },
> +	{ CCI_REG8(0x0900), 0x01 },
> +	{ CCI_REG8(0x0901), 0x22 },
> +	{ CCI_REG8(0x0902), 0x08 },

I believe these registers have names, too.

> +	{ IMX471_REG_DIG_CROP_X_OFFSET, 208 },
> +	{ IMX471_REG_DIG_CROP_Y_OFFSET, 108 },
> +	{ IMX471_REG_DIG_CROP_WIDTH, 1928 },
> +	{ IMX471_REG_DIG_CROP_HEIGHT, 1088 },
> +	{ IMX471_REG_X_OUTPUT_SIZE, 1928 },
> +	{ IMX471_REG_Y_OUTPUT_SIZE, 1088 },
> +	{ CCI_REG8(0x0301), 0x06 },
> +	{ CCI_REG8(0x0303), 0x02 },
> +	{ CCI_REG8(0x0305), 0x02 },
> +	{ CCI_REG8(0x0306), 0x00 },
> +	{ CCI_REG8(0x0307), 0x79 },
> +	{ CCI_REG8(0x030b), 0x01 },
> +	{ CCI_REG8(0x030d), 0x02 },
> +	{ CCI_REG8(0x030e), 0x00 },
> +	{ CCI_REG8(0x030f), 0x53 },
> +	{ CCI_REG8(0x0310), 0x01 },

Ditto.

> +	{ IMX471_REG_EXPOSURE, IMX471_EXPOSURE_DEFAULT },
> +	{ CCI_REG8(0x3f4c), 0x81 },
> +	{ CCI_REG8(0x3f4d), 0x81 },
> +	{ CCI_REG8(0x3f78), 0x01 },
> +	{ CCI_REG8(0x3f79), 0x31 },
> +	{ CCI_REG8(0x3ffe), 0x00 },
> +	{ CCI_REG8(0x3fff), 0x8a },
> +	{ CCI_REG8(0x5f0a), 0xb6 },
> +};
> +
> +static const char * const imx471_test_pattern_menu[] = {
> +	"Disabled",
> +	"Solid Colour",
> +	"Eight Vertical Colour Bars",
> +	"Colour Bars With Fade to Grey",
> +	"Pseudorandom Sequence (PN9)",
> +};
> +
> +static const s64 link_freq_menu_items[] = {
> +	IMX471_LINK_FREQ_DEFAULT,
> +};
> +
> +/*
> + * The Bayer formats for the flipping.
> + * - no flip
> + * - h flip
> + * - v flip
> + * - h and v flips
> + */
> +static const u32 imx471_hv_flips_bayer_order[] = {
> +	MEDIA_BUS_FMT_SRGGB10_1X10,
> +	MEDIA_BUS_FMT_SGRBG10_1X10,
> +	MEDIA_BUS_FMT_SGBRG10_1X10,
> +	MEDIA_BUS_FMT_SBGGR10_1X10,
> +};
> +
> +static const struct imx471_mode imx471_modes[] = {
> +	{
> +		.width = 1928,
> +		.height = 1088,
> +		.fll_def = 1308,
> +		.fll_min = 1308,
> +		.llp = 2328,
> +		.link_freq_index = IMX471_LINK_FREQ_INDEX,
> +		.default_mode_regs = mode_1928x1088_regs,
> +		.default_mode_regs_length = ARRAY_SIZE(mode_1928x1088_regs),
> +	},
> +};
> +
> +static int imx471_get_regulators(struct device *dev, struct imx471 *sensor)
> +{
> +	for (unsigned int i = 0; i < ARRAY_SIZE(imx471_supply_name); i++)
> +		sensor->supplies[i].supply = imx471_supply_name[i];
> +
> +	return devm_regulator_bulk_get(dev, ARRAY_SIZE(imx471_supply_name),
> +				       sensor->supplies);
> +}
> +
> +static int imx471_set_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct imx471 *sensor = container_of_const(ctrl->handler,
> +						   struct imx471,
> +						   ctrl_handler);
> +	struct v4l2_subdev_state *state =
> +			v4l2_subdev_get_locked_active_state(&sensor->sd);
> +	const struct v4l2_mbus_framefmt *format =
> +			v4l2_subdev_state_get_format(state, 0);
> +	s64 exposure_max;
> +	int ret;
> +
> +	if (ctrl->id == V4L2_CID_VBLANK) {

You can declare exposure_max here.

> +		exposure_max =
> +			format->height + ctrl->val - IMX471_EXPOSURE_MARGIN;
> +		ret = __v4l2_ctrl_modify_range(sensor->exposure,
> +					       sensor->exposure->minimum,
> +					       exposure_max,
> +					       sensor->exposure->step,
> +					       exposure_max);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	/* V4L2 controls values will be applied only when power is already up */
> +	if (!pm_runtime_get_if_in_use(sensor->dev))
> +		return 0;
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_ANALOGUE_GAIN:
> +		ret = cci_write(sensor->regmap, IMX471_REG_ANALOG_GAIN,
> +				ctrl->val, NULL);
> +		break;
> +	case V4L2_CID_DIGITAL_GAIN:
> +		ret = cci_write(sensor->regmap, IMX471_REG_DIG_GAIN_GLOBAL,
> +				ctrl->val, NULL);
> +		break;
> +	case V4L2_CID_EXPOSURE:
> +		ret = cci_write(sensor->regmap, IMX471_REG_EXPOSURE,
> +				ctrl->val, &ret);
> +		break;
> +	case V4L2_CID_VBLANK:
> +		/* Update FLL that meets expected vertical blanking */
> +		ret = cci_write(sensor->regmap, IMX471_REG_FLL,
> +				format->height + ctrl->val, &ret);
> +		break;
> +	case V4L2_CID_TEST_PATTERN:
> +		ret = cci_write(sensor->regmap, IMX471_REG_TEST_PATTERN,
> +				ctrl->val, NULL);
> +		break;
> +	case V4L2_CID_HFLIP:
> +	case V4L2_CID_VFLIP:
> +		ret = cci_write(sensor->regmap, IMX471_REG_ORIENTATION,
> +				sensor->hflip->val | sensor->vflip->val << 1, NULL);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +		dev_info(sensor->dev, "ctrl(id:0x%x,val:0x%x) is not handled",
> +			 ctrl->id, ctrl->val);
> +		break;
> +	}
> +
> +	pm_runtime_put(sensor->dev);
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_ctrl_ops imx471_ctrl_ops = {
> +	.s_ctrl = imx471_set_ctrl,
> +};
> +
> +static u32 imx471_get_format_code(struct imx471 *sensor)
> +{
> +	unsigned int i;
> +
> +	i = (sensor->vflip->val ? 2 : 0) | (sensor->hflip->val ? 1 : 0);
> +
> +	return imx471_hv_flips_bayer_order[i];
> +}
> +
> +static int imx471_enum_mbus_code(struct v4l2_subdev *sd,
> +				 struct v4l2_subdev_state *sd_state,
> +				 struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	struct imx471 *sensor = to_imx471(sd);
> +
> +	if (code->index >= (ARRAY_SIZE(imx471_hv_flips_bayer_order) / 4))
> +		return -EINVAL;
> +
> +	code->code = imx471_get_format_code(sensor);
> +
> +	return 0;
> +}
> +
> +static int imx471_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(imx471_modes))
> +		return -EINVAL;
> +
> +	fse->min_width = imx471_modes[fse->index].width;
> +	fse->max_width = fse->min_width;
> +	fse->min_height = imx471_modes[fse->index].height;
> +	fse->max_height = fse->min_height;
> +
> +	return 0;
> +}
> +
> +static void imx471_update_pad_format(struct imx471 *sensor,
> +				     const struct imx471_mode *mode,
> +				     struct v4l2_subdev_format *fmt)
> +{
> +	fmt->format.code = imx471_get_format_code(sensor);
> +	fmt->format.width = mode->width;
> +	fmt->format.height = mode->height;
> +	fmt->format.field = V4L2_FIELD_NONE;
> +}
> +
> +static int imx471_set_pad_format(struct v4l2_subdev *sd,
> +				 struct v4l2_subdev_state *sd_state,
> +				 struct v4l2_subdev_format *fmt)
> +{
> +	struct imx471 *sensor = to_imx471(sd);
> +	const struct imx471_mode *mode;
> +	u64 pixel_rate;
> +	int h_blank;
> +	int ret;
> +
> +	mode = v4l2_find_nearest_size(imx471_modes,
> +				      ARRAY_SIZE(imx471_modes),
> +				      width, height,
> +				      fmt->format.width, fmt->format.height);

Fits on fewer lines.

> +
> +	imx471_update_pad_format(sensor, mode, fmt);
> +
> +	*v4l2_subdev_state_get_format(sd_state, fmt->pad) = fmt->format;
> +
> +	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> +		return 0;
> +
> +	if (media_entity_is_streaming(&sensor->sd.entity))
> +		return -EBUSY;
> +
> +	pixel_rate = div_u64(IMX471_LINK_FREQ_DEFAULT * 2 * 4, 10);
> +	ret = __v4l2_ctrl_modify_range(sensor->pixel_rate,
> +				       V4L2_CID_PIXEL_RATE,
> +				       pixel_rate, 1, pixel_rate);
> +	if (ret)
> +		return ret;
> +
> +	ret = __v4l2_ctrl_modify_range(sensor->vblank,
> +				       mode->fll_min - mode->height,
> +				       IMX471_FLL_MAX - mode->height,
> +				       1,
> +				       mode->fll_def - mode->height);
> +	if (ret)
> +		return ret;
> +
> +	h_blank = mode->llp - mode->width;
> +	/*
> +	 * Currently hblank is not changeable.
> +	 * So FPS control is done only by vblank.
> +	 */
> +	return __v4l2_ctrl_modify_range(sensor->hblank, h_blank,
> +					h_blank, 1, h_blank);
> +}
> +
> +static int imx471_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, sel->pad);
> +		break;
> +
> +	case V4L2_SEL_TGT_NATIVE_SIZE:
> +		sel->r.top = 0;
> +		sel->r.left = 0;
> +		sel->r.width = IMX471_NATIVE_WIDTH;
> +		sel->r.height = IMX471_NATIVE_HEIGHT;
> +		return 0;
> +
> +	case V4L2_SEL_TGT_CROP_DEFAULT:
> +	case V4L2_SEL_TGT_CROP_BOUNDS:
> +		sel->r.top = IMX471_PIXEL_ARRAY_TOP;
> +		sel->r.left = IMX471_PIXEL_ARRAY_LEFT;
> +		sel->r.width = IMX471_PIXEL_ARRAY_WIDTH;
> +		sel->r.height = IMX471_PIXEL_ARRAY_HEIGHT;
> +		return 0;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int imx471_init_state(struct v4l2_subdev *sd,
> +			     struct v4l2_subdev_state *sd_state)
> +{
> +	struct v4l2_subdev_format fmt = {
> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
> +		.format = {
> +			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
> +			.width = imx471_modes[0].width,
> +			.height = imx471_modes[0].height,
> +		},
> +	};
> +
> +	return imx471_set_pad_format(sd, sd_state, &fmt);
> +}
> +
> +static int imx471_identify_module(struct imx471 *sensor)
> +{
> +	int ret;
> +	u64 val;
> +
> +	ret = cci_read(sensor->regmap, IMX471_REG_CHIP_ID, &val, NULL);
> +	if (ret)
> +		return dev_err_probe(sensor->dev, ret,
> +				     "failed to read chip id\n");
> +
> +	if (val != IMX471_CHIP_ID)
> +		return dev_err_probe(sensor->dev, -EIO,
> +				     "chip id mismatch: %x!=%llx\n",
> +				     IMX471_CHIP_ID, val);
> +
> +	return 0;
> +}
> +
> +static int imx471_power_off(struct device *dev)
> +{
> +	struct v4l2_subdev *sd = dev_get_drvdata(dev);
> +	struct imx471 *sensor = to_imx471(sd);
> +
> +	clk_disable_unprepare(sensor->img_clk);
> +	gpiod_set_value_cansleep(sensor->reset_gpio, 1);
> +
> +	regulator_bulk_disable(ARRAY_SIZE(imx471_supply_name), sensor->supplies);
> +
> +	return 0;
> +}
> +
> +static int imx471_power_on(struct device *dev)
> +{
> +	struct v4l2_subdev *sd = dev_get_drvdata(dev);
> +	struct imx471 *sensor = to_imx471(sd);
> +	int ret;
> +
> +	ret = regulator_bulk_enable(ARRAY_SIZE(imx471_supply_name), sensor->supplies);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to enable regulators: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(sensor->img_clk);
> +	if (ret < 0) {
> +		regulator_bulk_disable(ARRAY_SIZE(imx471_supply_name), sensor->supplies);
> +		dev_err(dev, "failed to enable imaging clock: %d", ret);
> +		return ret;
> +	}
> +
> +	gpiod_set_value_cansleep(sensor->reset_gpio, 0);
> +
> +	usleep_range(10000, 15000);
> +
> +	return 0;
> +}
> +
> +static int imx471_enable_stream(struct v4l2_subdev *sd,
> +				struct v4l2_subdev_state *state,
> +				u32 pad, u64 streams_mask)
> +{
> +	struct imx471 *sensor = to_imx471(sd);
> +	const struct imx471_mode *mode;
> +	struct v4l2_mbus_framefmt *fmt;
> +	int ret;
> +
> +	ret = pm_runtime_resume_and_get(sensor->dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = imx471_identify_module(sensor);
> +	if (ret)
> +		return ret;
> +
> +	ret = cci_multi_reg_write(sensor->regmap, imx471_global_regs,
> +				  ARRAY_SIZE(imx471_global_regs), NULL);
> +	if (ret) {
> +		dev_err(sensor->dev, "failed to set global settings: %d", ret);
> +		goto error_powerdown;
> +	}
> +
> +	state = v4l2_subdev_get_locked_active_state(&sensor->sd);
> +	fmt = v4l2_subdev_state_get_format(state, 0);
> +	mode = v4l2_find_nearest_size(imx471_modes, ARRAY_SIZE(imx471_modes),
> +				      width, height, fmt->width, fmt->height);
> +
> +	ret = cci_multi_reg_write(sensor->regmap, mode->default_mode_regs,
> +				  mode->default_mode_regs_length, NULL);
> +	if (ret) {
> +		dev_err(sensor->dev, "failed to set mode: %d", ret);
> +		goto error_powerdown;
> +	}
> +
> +	ret = cci_write(sensor->regmap, IMX471_REG_DPGA_USE_GLOBAL_GAIN, 1, NULL);
> +	if (ret)
> +		goto error_powerdown;
> +
> +	ret = __v4l2_ctrl_handler_setup(&sensor->ctrl_handler);
> +	if (ret)
> +		goto error_powerdown;
> +
> +	ret = cci_write(sensor->regmap, IMX471_REG_MODE_SELECT,
> +			IMX471_MODE_STREAMING, NULL);
> +	if (ret)
> +		goto error_powerdown;
> +
> +	__v4l2_ctrl_grab(sensor->vflip, true);
> +	__v4l2_ctrl_grab(sensor->hflip, true);
> +
> +	return ret;
> +
> +error_powerdown:
> +	pm_runtime_put(sensor->dev);
> +
> +	return ret;
> +}
> +
> +static int imx471_disable_stream(struct v4l2_subdev *sd,
> +				 struct v4l2_subdev_state *state,
> +				 u32 pad, u64 streams_mask)
> +{
> +	struct imx471 *sensor = to_imx471(sd);
> +	int ret;
> +
> +	ret = cci_write(sensor->regmap, IMX471_REG_MODE_SELECT,
> +			IMX471_MODE_STANDBY, NULL);
> +	pm_runtime_put(sensor->dev);
> +
> +	if (ret)
> +		dev_err(sensor->dev,
> +			"failed to disable stream with return value: %d\n",
> +			ret);
> +
> +	__v4l2_ctrl_grab(sensor->vflip, false);
> +	__v4l2_ctrl_grab(sensor->hflip, false);
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops imx471_video_ops = {
> +	.s_stream = v4l2_subdev_s_stream_helper,
> +};
> +
> +static const struct v4l2_subdev_pad_ops imx471_pad_ops = {
> +	.enum_mbus_code = imx471_enum_mbus_code,
> +	.get_fmt = v4l2_subdev_get_fmt,
> +	.set_fmt = imx471_set_pad_format,
> +	.get_selection = imx471_get_selection,
> +	.enum_frame_size = imx471_enum_frame_size,
> +	.enable_streams = imx471_enable_stream,
> +	.disable_streams = imx471_disable_stream,
> +};
> +
> +static const struct v4l2_subdev_ops imx471_subdev_ops = {
> +	.video = &imx471_video_ops,
> +	.pad = &imx471_pad_ops,
> +};
> +
> +static const struct v4l2_subdev_internal_ops imx471_internal_ops = {
> +	.init_state = imx471_init_state,
> +};
> +
> +static int imx471_init_controls(struct imx471 *sensor)
> +{
> +	const struct imx471_mode *mode = &imx471_modes[0];
> +	struct v4l2_fwnode_device_properties props;
> +	struct v4l2_ctrl_handler *ctrl_hdlr;
> +	struct v4l2_ctrl *link_freq;
> +	s64 exposure_max, hblank;
> +	u64 pixel_rate;
> +	int ret;
> +
> +	ctrl_hdlr = &sensor->ctrl_handler;

You can initialise this in declaration.

> +	v4l2_ctrl_handler_init(ctrl_hdlr, 12);

Initialising the handler allocates memory so pelase move under
v4l2_fwnode_device_parse() below.

> +
> +	ret = v4l2_fwnode_device_parse(sensor->dev, &props);
> +	if (ret) {
> +		dev_err(sensor->dev, "failed to parse fwnode: %d", ret);
> +		return ret;
> +	}
> +
> +	v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &imx471_ctrl_ops, &props);
> +
> +	link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> +					   &imx471_ctrl_ops,
> +					   V4L2_CID_LINK_FREQ,
> +					   ARRAY_SIZE(link_freq_menu_items) - 1,
> +					   0,
> +					   link_freq_menu_items);
> +
> +	/* pixel_rate = link_freq * 2 * nr_of_lanes / bits_per_sample */
> +	pixel_rate = div_u64(IMX471_LINK_FREQ_DEFAULT * 2 * 4, 10);
> +
> +	sensor->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops,
> +					       V4L2_CID_PIXEL_RATE, pixel_rate,
> +					       pixel_rate, 1, pixel_rate);
> +
> +	sensor->vblank = v4l2_ctrl_new_std(ctrl_hdlr,
> +					   &imx471_ctrl_ops,
> +					   V4L2_CID_VBLANK,
> +					   mode->fll_min - mode->height,
> +					   IMX471_FLL_MAX - mode->height,
> +					   1,
> +					   mode->fll_def - mode->height);
> +
> +	hblank = mode->llp - mode->width;
> +	sensor->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops,
> +					   V4L2_CID_HBLANK, hblank, hblank,
> +					   1, hblank);
> +
> +	/* fll >= exposure time + adjust parameter (default value is 18) */
> +	exposure_max = mode->fll_def - IMX471_EXPOSURE_MARGIN;
> +	sensor->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops,
> +					     V4L2_CID_EXPOSURE,
> +					     IMX471_EXPOSURE_MIN, exposure_max,
> +					     IMX471_EXPOSURE_STEP,
> +					     IMX471_EXPOSURE_DEFAULT);
> +
> +	v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
> +			  IMX471_ANA_GAIN_MIN, IMX471_ANA_GAIN_MAX,
> +			  IMX471_ANA_GAIN_STEP, IMX471_ANA_GAIN_DEFAULT);
> +
> +	v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> +			  IMX471_DGTL_GAIN_MIN, IMX471_DGTL_GAIN_MAX,
> +			  IMX471_DGTL_GAIN_STEP, IMX471_DGTL_GAIN_DEFAULT);
> +
> +	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &imx471_ctrl_ops,
> +				     V4L2_CID_TEST_PATTERN,
> +				     ARRAY_SIZE(imx471_test_pattern_menu) - 1,
> +				     0, 0, imx471_test_pattern_menu);
> +
> +	sensor->hflip = v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops,
> +					  V4L2_CID_HFLIP, 0, 1, 1, 0);
> +
> +	sensor->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &imx471_ctrl_ops,
> +					  V4L2_CID_VFLIP, 0, 1, 1, 0);
> +
> +	if (ctrl_hdlr->error) {
> +		dev_err(sensor->dev, "%s control init failed: %d",
> +			__func__, ctrl_hdlr->error);
> +		goto error;
> +	}
> +
> +	link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +	sensor->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +	sensor->hflip->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;
> +	sensor->vflip->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;
> +
> +	sensor->sd.ctrl_handler = ctrl_hdlr;
> +
> +	return 0;
> +
> +error:
> +	v4l2_ctrl_handler_free(ctrl_hdlr);
> +
> +	return ctrl_hdlr->error;
> +}
> +
> +static int imx471_check_hwcfg(struct imx471 *sensor)
> +{
> +	struct v4l2_fwnode_endpoint bus_cfg = {
> +		.bus_type = V4L2_MBUS_CSI2_DPHY,
> +	};
> +	struct fwnode_handle *ep, *fwnode = dev_fwnode(sensor->dev);
> +	unsigned long link_freq_bitmap;
> +	struct clk *clk;
> +	int ret;
> +
> +	clk = devm_v4l2_sensor_clk_get(sensor->dev, NULL);
> +	if (IS_ERR(clk))
> +		return dev_err_probe(sensor->dev, PTR_ERR(clk),
> +				     "can't get clock frequency\n");
> +
> +	if (clk_get_rate(clk) != IMX471_EXT_CLK)
> +		return dev_err_probe(sensor->dev, -EINVAL,
> +				     "external clock %lu is not supported\n",
> +				     clk_get_rate(clk));
> +
> +	ep = fwnode_graph_get_endpoint_by_id(fwnode, 0, 0, 0);
> +	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
> +	fwnode_handle_put(ep);
> +	if (ret)
> +		return dev_err_probe(sensor->dev, ret,
> +				     "parsing endpoint failed");
> +
> +	ret = v4l2_link_freq_to_bitmap(sensor->dev, bus_cfg.link_frequencies,
> +				       bus_cfg.nr_of_link_frequencies,
> +				       link_freq_menu_items,
> +				       ARRAY_SIZE(link_freq_menu_items),
> +				       &link_freq_bitmap);
> +
> +	v4l2_fwnode_endpoint_free(&bus_cfg);
> +
> +	return ret;
> +}
> +
> +static int imx471_probe(struct i2c_client *client)
> +{
> +	struct imx471 *sensor;
> +	int ret;
> +
> +	sensor = devm_kzalloc(&client->dev, sizeof(*sensor), GFP_KERNEL);
> +	if (!sensor)
> +		return dev_err_probe(&client->dev, -ENOMEM,
> +				     "failed to allocate memory\n");
> +
> +	sensor->dev = &client->dev;
> +
> +	ret = imx471_check_hwcfg(sensor);
> +	if (ret)
> +		return dev_err_probe(sensor->dev, ret,
> +				     "failed to check hwcfg: %d\n", ret);
> +
> +	ret = imx471_get_regulators(sensor->dev, sensor);
> +	if (ret)
> +		return dev_err_probe(sensor->dev, ret,
> +				     "failed to get regulators\n");
> +
> +	sensor->reset_gpio = devm_gpiod_get_optional(sensor->dev, "reset",
> +						     GPIOD_OUT_HIGH);
> +	if (IS_ERR(sensor->reset_gpio))
> +		return dev_err_probe(sensor->dev, PTR_ERR(sensor->reset_gpio),
> +				     "failed to get reset gpio\n");
> +
> +	sensor->img_clk = devm_clk_get_optional(sensor->dev, NULL);
> +	if (IS_ERR(sensor->img_clk))
> +		return dev_err_probe(sensor->dev, PTR_ERR(sensor->img_clk),
> +				     "failed to get imaging clock\n");
> +
> +	v4l2_i2c_subdev_init(&sensor->sd, client, &imx471_subdev_ops);
> +
> +	sensor->regmap = devm_cci_regmap_init_i2c(client, 16);
> +	if (IS_ERR(sensor->regmap))
> +		return dev_err_probe(sensor->dev, PTR_ERR(sensor->regmap),
> +				     "failed to initialize CCI\n");
> +
> +	ret = imx471_power_on(sensor->dev);
> +	if (ret)
> +		return dev_err_probe(sensor->dev, ret,
> +				     "failed to power on\n");
> +
> +	ret = imx471_identify_module(sensor);
> +	if (ret) {
> +		dev_err_probe(sensor->dev, ret, "failed to find sensor: %d", ret);
> +		goto error_power_off;
> +	}
> +
> +	ret = imx471_init_controls(sensor);
> +	if (ret) {
> +		dev_err_probe(sensor->dev, ret, "failed to init controls: %d", ret);
> +		goto error_power_off;
> +	}
> +
> +	sensor->sd.internal_ops = &imx471_internal_ops;
> +	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	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_probe(sensor->dev, ret, "failed to init entity pads: %d", ret);
> +		goto error_v4l2_ctrl_handler_free;
> +	}
> +
> +	sensor->sd.state_lock = sensor->ctrl_handler.lock;
> +	ret = v4l2_subdev_init_finalize(&sensor->sd);
> +	if (ret < 0) {
> +		dev_err_probe(sensor->dev, ret, "failed to init subdev: %d", ret);
> +		goto error_media_entity_pm;
> +	}
> +
> +	pm_runtime_set_active(sensor->dev);
> +	pm_runtime_enable(sensor->dev);
> +
> +	ret = v4l2_async_register_subdev_sensor(&sensor->sd);
> +	if (ret < 0)
> +		goto error_v4l2_subdev_cleanup;
> +
> +	pm_runtime_idle(sensor->dev);
> +
> +	return 0;
> +
> +error_v4l2_subdev_cleanup:
> +	pm_runtime_disable(sensor->dev);
> +	pm_runtime_set_suspended(sensor->dev);
> +	v4l2_subdev_cleanup(&sensor->sd);
> +
> +error_media_entity_pm:
> +	media_entity_cleanup(&sensor->sd.entity);
> +
> +error_v4l2_ctrl_handler_free:
> +	v4l2_ctrl_handler_free(sensor->sd.ctrl_handler);
> +
> +error_power_off:
> +	imx471_power_off(sensor->dev);
> +
> +	return ret;
> +}
> +
> +static void imx471_remove(struct i2c_client *client)
> +{
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +
> +	v4l2_async_unregister_subdev(sd);
> +	v4l2_subdev_cleanup(sd);
> +	media_entity_cleanup(&sd->entity);
> +	v4l2_ctrl_handler_free(sd->ctrl_handler);
> +
> +	pm_runtime_disable(&client->dev);
> +
> +	if (!pm_runtime_status_suspended(&client->dev)) {
> +		imx471_power_off(&client->dev);
> +		pm_runtime_set_suspended(&client->dev);
> +	}
> +}
> +
> +static DEFINE_RUNTIME_DEV_PM_OPS(imx471_pm_ops, imx471_power_off,
> +				 imx471_power_on, NULL);
> +
> +static const struct acpi_device_id imx471_acpi_ids[] __maybe_unused = {
> +	{ "SONY471A" },
> +	{ "TBE20A0" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(acpi, imx471_acpi_ids);
> +
> +static struct i2c_driver imx471_i2c_driver = {
> +	.driver = {
> +		.name = "imx471",
> +		.acpi_match_table = ACPI_PTR(imx471_acpi_ids),
> +		.pm = pm_sleep_ptr(&imx471_pm_ops),
> +	},
> +	.probe = imx471_probe,
> +	.remove = imx471_remove,
> +};
> +module_i2c_driver(imx471_i2c_driver);
> +
> +MODULE_AUTHOR("Jimmy Su <jimmy.su@intel.com>");
> +MODULE_AUTHOR("Serin Yeh <serin.yeh@intel.com>");
> +MODULE_AUTHOR("Kate Hsuan <hpa@redhat.com>");
> +MODULE_DESCRIPTION("Sony imx471 sensor driver");
> +MODULE_LICENSE("GPL");

-- 
Kind regards,

Sakari Ailus