diff mbox series

[v6,02/15] media: i2c: imx219: Add internal image sink pad

Message ID 20240301213231.10340-3-laurent.pinchart@ideasonboard.com (mailing list archive)
State New, archived
Headers show
Series media: Add driver for the Raspberry Pi <5 CSI-2 receiver | expand

Commit Message

Laurent Pinchart March 1, 2024, 9:32 p.m. UTC
Use the newly added internal pad API to expose the internal
configuration of the sensor to userspace in a standard manner. This also
paves the way for adding support for embedded data with an additional
internal pad.

To maintain compatibility with existing userspace that may operate on
pad 0 unconditionally, keep the source pad numbered 0 and number the
internal image pad 1.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/i2c/imx219.c | 169 +++++++++++++++++++++++++++++--------
 1 file changed, 133 insertions(+), 36 deletions(-)

Comments

Jacopo Mondi March 4, 2024, 9:13 a.m. UTC | #1
Hi Laurent

On Fri, Mar 01, 2024 at 11:32:17PM +0200, Laurent Pinchart wrote:
> Use the newly added internal pad API to expose the internal
> configuration of the sensor to userspace in a standard manner. This also
> paves the way for adding support for embedded data with an additional
> internal pad.
>
> To maintain compatibility with existing userspace that may operate on
> pad 0 unconditionally, keep the source pad numbered 0 and number the
> internal image pad 1.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  drivers/media/i2c/imx219.c | 169 +++++++++++++++++++++++++++++--------
>  1 file changed, 133 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> index 3878da50860e..817bf192e4d9 100644
> --- a/drivers/media/i2c/imx219.c
> +++ b/drivers/media/i2c/imx219.c
> @@ -140,6 +140,7 @@
>  #define IMX219_DEFAULT_LINK_FREQ_4LANE	363000000
>
>  /* IMX219 native and active pixel array size. */
> +#define IMX219_NATIVE_FORMAT		MEDIA_BUS_FMT_SRGGB10_1X10
>  #define IMX219_NATIVE_WIDTH		3296U
>  #define IMX219_NATIVE_HEIGHT		2480U
>  #define IMX219_PIXEL_ARRAY_LEFT		8U
> @@ -312,9 +313,15 @@ static const struct imx219_mode supported_modes[] = {
>  	},
>  };
>
> +enum imx219_pad_ids {
> +	IMX219_PAD_SOURCE,
> +	IMX219_PAD_IMAGE,

Feels a bit weird for the internal source pad to be named "Image" as
it will (if I understand correctly) host both the image and metadata
streams.

However, I have an hard time proposing a different name, but we should
find something that should be used in all drivers ported to this new
API.

Enough with bikeshedding anyway, this is a tiny detail.

> +	IMX219_NUM_PADS,
> +};
> +
>  struct imx219 {
>  	struct v4l2_subdev sd;
> -	struct media_pad pad;
> +	struct media_pad pads[IMX219_NUM_PADS];
>
>  	struct regmap *regmap;
>  	struct clk *xclk; /* system clock to IMX219 */
> @@ -374,7 +381,7 @@ static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
>  	int ret = 0;
>
>  	state = v4l2_subdev_get_locked_active_state(&imx219->sd);
> -	format = v4l2_subdev_state_get_format(state, 0);
> +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
>
>  	if (ctrl->id == V4L2_CID_VBLANK) {
>  		int exposure_max, exposure_def;
> @@ -593,8 +600,8 @@ static int imx219_set_framefmt(struct imx219 *imx219,
>  	u64 bin_h, bin_v;
>  	int ret = 0;
>
> -	format = v4l2_subdev_state_get_format(state, 0);
> -	crop = v4l2_subdev_state_get_crop(state, 0);
> +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
>
>  	switch (format->code) {
>  	case MEDIA_BUS_FMT_SRGGB8_1X8:
> @@ -764,10 +771,25 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
>  {
>  	struct imx219 *imx219 = to_imx219(sd);
>
> -	if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> -		return -EINVAL;
> +	if (code->pad == IMX219_PAD_IMAGE) {
> +		/* The internal image pad is hardwired to the native format. */
> +		if (code->index)
> +			return -EINVAL;
>
> -	code->code = imx219_get_format_code(imx219, imx219_mbus_formats[code->index * 4]);
> +		code->code = IMX219_NATIVE_FORMAT;

If you return 0 here you can spare the else {} branch. Same in the
function below.

> +	} else {
> +		/*
> +		 * On the source pad, the sensor supports multiple raw formats
> +		 * with different bit depths.
> +		 */
> +		u32 format;
> +
> +		if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> +			return -EINVAL;
> +
> +		format = imx219_mbus_formats[code->index * 4];
> +		code->code = imx219_get_format_code(imx219, format);
> +	}
>
>  	return 0;
>  }
> @@ -777,19 +799,25 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
>  				  struct v4l2_subdev_frame_size_enum *fse)
>  {
>  	struct imx219 *imx219 = to_imx219(sd);
> -	u32 code;
>
> -	if (fse->index >= ARRAY_SIZE(supported_modes))
> -		return -EINVAL;
> +	if (fse->pad == IMX219_PAD_IMAGE) {
> +		if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
> +			return -EINVAL;
>
> -	code = imx219_get_format_code(imx219, fse->code);
> -	if (fse->code != code)
> -		return -EINVAL;
> +		fse->min_width = IMX219_NATIVE_WIDTH;
> +		fse->max_width = IMX219_NATIVE_WIDTH;
> +		fse->min_height = IMX219_NATIVE_HEIGHT;
> +		fse->max_height = IMX219_NATIVE_HEIGHT;
> +	} else {
> +		if (fse->code != imx219_get_format_code(imx219, fse->code) ||
> +		    fse->index >= ARRAY_SIZE(supported_modes))
> +			return -EINVAL;
>
> -	fse->min_width = supported_modes[fse->index].width;
> -	fse->max_width = fse->min_width;
> -	fse->min_height = supported_modes[fse->index].height;
> -	fse->max_height = fse->min_height;
> +		fse->min_width = supported_modes[fse->index].width;
> +		fse->max_width = fse->min_width;
> +		fse->min_height = supported_modes[fse->index].height;
> +		fse->max_height = fse->min_height;
> +	}
>
>  	return 0;
>  }
> @@ -801,9 +829,17 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
>  	struct imx219 *imx219 = to_imx219(sd);
>  	const struct imx219_mode *mode;
>  	struct v4l2_mbus_framefmt *format;
> +	struct v4l2_rect *compose;
>  	struct v4l2_rect *crop;
>  	unsigned int bin_h, bin_v;
>
> +	/*
> +	 * The driver is mode-based, the format can be set on the source pad
> +	 * only.
> +	 */
> +	if (fmt->pad != IMX219_PAD_SOURCE)
> +		return v4l2_subdev_get_fmt(sd, state, fmt);
> +
>  	/*
>  	 * Adjust the requested format to match the closest mode. The Bayer
>  	 * order varies with flips.
> @@ -822,22 +858,51 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
>  	fmt->format.quantization = V4L2_QUANTIZATION_FULL_RANGE;
>  	fmt->format.xfer_func = V4L2_XFER_FUNC_NONE;
>
> -	format = v4l2_subdev_state_get_format(state, 0);
> +	/* Propagate the format through the sensor. */
> +
> +	/* The image pad models the pixel array, and thus has a fixed size. */
> +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_IMAGE);
>  	*format = fmt->format;

Is this assignment needed ?

Isn't 'fmt' meant to be applied at pad #0 ? Also, you overwrite the
code and size below, do the rest of the 'struct v4l2_mbus_framefmt'
fields apply to pad #1 (field, colorspace, quantization etc ? If pad
#1 represents the pixel array, I don't think they do).

Also, can't the pad #1 format be initialized by .init_state() and never
touched again ?


> +	format->code = IMX219_NATIVE_FORMAT;
> +	format->width = IMX219_NATIVE_WIDTH;
> +	format->height = IMX219_NATIVE_HEIGHT;
>
>  	/*
>  	 * Use binning to maximize the crop rectangle size, and centre it in the
>  	 * sensor.
>  	 */
> -	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / format->width, 2U);
> -	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / format->height, 2U);
> +	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / fmt->format.width, 2U);
> +	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / fmt->format.height, 2U);
>
> -	crop = v4l2_subdev_state_get_crop(state, 0);
> -	crop->width = format->width * bin_h;
> -	crop->height = format->height * bin_v;
> +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> +	crop->width = fmt->format.width * bin_h;
> +	crop->height = fmt->format.height * bin_v;
>  	crop->left = (IMX219_NATIVE_WIDTH - crop->width) / 2;
>  	crop->top = (IMX219_NATIVE_HEIGHT - crop->height) / 2;

This is no different than before, but I now wonder if VGA is actually
obtained by cropping down to 1280x960 and then by a 2x2 binning, or is
there a 4x4 binning mode. I presume this is correct though, as this has been
validated by many people.

>
> +	/*
> +	 * The compose rectangle models binning, its size is the sensor output
> +	 * size.
> +	 */
> +	compose = v4l2_subdev_state_get_compose(state, IMX219_PAD_IMAGE);
> +	compose->left = 0;
> +	compose->top = 0;
> +	compose->width = fmt->format.width;
> +	compose->height = fmt->format.height;
> +
> +	/*
> +	 * No mode use digital crop, the source pad crop rectangle size and
> +	 * format are thus identical to the image pad compose rectangle.
> +	 */
> +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE);
> +	crop->left = 0;
> +	crop->top = 0;
> +	crop->width = fmt->format.width;
> +	crop->height = fmt->format.height;
> +
> +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> +	*format = fmt->format;
> +
>  	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
>  		int exposure_max;
>  		int exposure_def;
> @@ -874,13 +939,13 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
>  				struct v4l2_subdev_state *state,
>  				struct v4l2_subdev_selection *sel)
>  {
> -	switch (sel->target) {
> -	case V4L2_SEL_TGT_CROP: {
> -		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> -		return 0;
> -	}
> +	struct v4l2_rect *compose;
>
> +	switch (sel->target) {
>  	case V4L2_SEL_TGT_NATIVE_SIZE:
> +		if (sel->pad != IMX219_PAD_IMAGE)
> +			return -EINVAL;
> +
>  		sel->r.top = 0;
>  		sel->r.left = 0;
>  		sel->r.width = IMX219_NATIVE_WIDTH;
> @@ -890,11 +955,35 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
>
>  	case V4L2_SEL_TGT_CROP_DEFAULT:
>  	case V4L2_SEL_TGT_CROP_BOUNDS:
> -		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> -		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> -		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> -		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> +		switch (sel->pad) {
> +		case IMX219_PAD_IMAGE:
> +			sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> +			sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> +			sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> +			sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> +			return 0;
>
> +		case IMX219_PAD_SOURCE:
> +			compose = v4l2_subdev_state_get_compose(state,
> +								IMX219_PAD_IMAGE);
> +			sel->r.top = 0;
> +			sel->r.left = 0;
> +			sel->r.width = compose->width;
> +			sel->r.height = compose->height;
> +			return 0;
> +		}
> +
> +		break;
> +
> +	case V4L2_SEL_TGT_CROP:
> +		sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
> +		return 0;
> +
> +	case V4L2_SEL_TGT_COMPOSE:
> +		if (sel->pad != IMX219_PAD_IMAGE)
> +			return -EINVAL;
> +
> +		sel->r = *v4l2_subdev_state_get_compose(state, sel->pad);
>  		return 0;

Do we need to support TGT_COMPOSE_BOUNDS for PAD_IMAGE ? I would have
suggested V4L2_SEL_TGT_COMPOSE_DEFAULT too, but according to the spec
it does not apply to subdevices.

>  	}
>
> @@ -906,7 +995,7 @@ static int imx219_init_state(struct v4l2_subdev *sd,
>  {
>  	struct v4l2_subdev_format fmt = {
>  		.which = V4L2_SUBDEV_FORMAT_TRY,
> -		.pad = 0,
> +		.pad = IMX219_PAD_SOURCE,
>  		.format = {
>  			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
>  			.width = supported_modes[0].width,

Why not intialize pad#1 format here an never touch it again ? Should
also the pad#1 crop and compose rectangles and pad#0 crop be
initialized here ?

> @@ -1174,10 +1263,18 @@ static int imx219_probe(struct i2c_client *client)
>  			    V4L2_SUBDEV_FL_HAS_EVENTS;
>  	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
>
> -	/* Initialize source pad */
> -	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
> +	/*
> +	 * Initialize the pads. To preserve backward compatibility with
> +	 * userspace that used the sensor before the introduction of the
> +	 * internal image pad, the external source pad is numbered 0 and the
> +	 * internal image pad numbered 1.
> +	 */
> +	imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> +	imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
> +					     | MEDIA_PAD_FL_INTERNAL;
>
> -	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
> +	ret = media_entity_pads_init(&imx219->sd.entity,
> +				     ARRAY_SIZE(imx219->pads), imx219->pads);
>  	if (ret) {
>  		dev_err(dev, "failed to init entity pads: %d\n", ret);
>  		goto error_handler_free;
> --
> Regards,
>
> Laurent Pinchart
>
>
Jacopo Mondi March 4, 2024, 9:38 a.m. UTC | #2
Hi Laurent

On Mon, Mar 04, 2024 at 10:13:47AM +0100, Jacopo Mondi wrote:
> Hi Laurent
>
> On Fri, Mar 01, 2024 at 11:32:17PM +0200, Laurent Pinchart wrote:
> > Use the newly added internal pad API to expose the internal
> > configuration of the sensor to userspace in a standard manner. This also
> > paves the way for adding support for embedded data with an additional
> > internal pad.
> >
> > To maintain compatibility with existing userspace that may operate on
> > pad 0 unconditionally, keep the source pad numbered 0 and number the
> > internal image pad 1.
> >
> > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > ---
> >  drivers/media/i2c/imx219.c | 169 +++++++++++++++++++++++++++++--------
> >  1 file changed, 133 insertions(+), 36 deletions(-)
> >
> > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > index 3878da50860e..817bf192e4d9 100644
> > --- a/drivers/media/i2c/imx219.c
> > +++ b/drivers/media/i2c/imx219.c
> > @@ -140,6 +140,7 @@
> >  #define IMX219_DEFAULT_LINK_FREQ_4LANE	363000000
> >
> >  /* IMX219 native and active pixel array size. */
> > +#define IMX219_NATIVE_FORMAT		MEDIA_BUS_FMT_SRGGB10_1X10
> >  #define IMX219_NATIVE_WIDTH		3296U
> >  #define IMX219_NATIVE_HEIGHT		2480U
> >  #define IMX219_PIXEL_ARRAY_LEFT		8U
> > @@ -312,9 +313,15 @@ static const struct imx219_mode supported_modes[] = {
> >  	},
> >  };
> >
> > +enum imx219_pad_ids {
> > +	IMX219_PAD_SOURCE,
> > +	IMX219_PAD_IMAGE,
>
> Feels a bit weird for the internal source pad to be named "Image" as
> it will (if I understand correctly) host both the image and metadata
> streams.
>
> However, I have an hard time proposing a different name, but we should
> find something that should be used in all drivers ported to this new
> API.
>
> Enough with bikeshedding anyway, this is a tiny detail.
>

Now that I've read 5/15 I now understand why this is called "IMAGE" :)

> > +	IMX219_NUM_PADS,
> > +};
> > +
> >  struct imx219 {
> >  	struct v4l2_subdev sd;
> > -	struct media_pad pad;
> > +	struct media_pad pads[IMX219_NUM_PADS];
> >
> >  	struct regmap *regmap;
> >  	struct clk *xclk; /* system clock to IMX219 */
> > @@ -374,7 +381,7 @@ static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
> >  	int ret = 0;
> >
> >  	state = v4l2_subdev_get_locked_active_state(&imx219->sd);
> > -	format = v4l2_subdev_state_get_format(state, 0);
> > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> >
> >  	if (ctrl->id == V4L2_CID_VBLANK) {
> >  		int exposure_max, exposure_def;
> > @@ -593,8 +600,8 @@ static int imx219_set_framefmt(struct imx219 *imx219,
> >  	u64 bin_h, bin_v;
> >  	int ret = 0;
> >
> > -	format = v4l2_subdev_state_get_format(state, 0);
> > -	crop = v4l2_subdev_state_get_crop(state, 0);
> > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> >
> >  	switch (format->code) {
> >  	case MEDIA_BUS_FMT_SRGGB8_1X8:
> > @@ -764,10 +771,25 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
> >  {
> >  	struct imx219 *imx219 = to_imx219(sd);
> >
> > -	if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > -		return -EINVAL;
> > +	if (code->pad == IMX219_PAD_IMAGE) {
> > +		/* The internal image pad is hardwired to the native format. */
> > +		if (code->index)
> > +			return -EINVAL;
> >
> > -	code->code = imx219_get_format_code(imx219, imx219_mbus_formats[code->index * 4]);
> > +		code->code = IMX219_NATIVE_FORMAT;
>
> If you return 0 here you can spare the else {} branch. Same in the
> function below.
>

You're reworking this in 5/15, so no need to change this and cause
rebase conflicts.

> > +	} else {
> > +		/*
> > +		 * On the source pad, the sensor supports multiple raw formats
> > +		 * with different bit depths.
> > +		 */
> > +		u32 format;
> > +
> > +		if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > +			return -EINVAL;
> > +
> > +		format = imx219_mbus_formats[code->index * 4];
> > +		code->code = imx219_get_format_code(imx219, format);
> > +	}
> >
> >  	return 0;
> >  }
> > @@ -777,19 +799,25 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> >  				  struct v4l2_subdev_frame_size_enum *fse)
> >  {
> >  	struct imx219 *imx219 = to_imx219(sd);
> > -	u32 code;
> >
> > -	if (fse->index >= ARRAY_SIZE(supported_modes))
> > -		return -EINVAL;
> > +	if (fse->pad == IMX219_PAD_IMAGE) {
> > +		if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
> > +			return -EINVAL;
> >
> > -	code = imx219_get_format_code(imx219, fse->code);
> > -	if (fse->code != code)
> > -		return -EINVAL;
> > +		fse->min_width = IMX219_NATIVE_WIDTH;
> > +		fse->max_width = IMX219_NATIVE_WIDTH;
> > +		fse->min_height = IMX219_NATIVE_HEIGHT;
> > +		fse->max_height = IMX219_NATIVE_HEIGHT;
> > +	} else {
> > +		if (fse->code != imx219_get_format_code(imx219, fse->code) ||
> > +		    fse->index >= ARRAY_SIZE(supported_modes))
> > +			return -EINVAL;
> >
> > -	fse->min_width = supported_modes[fse->index].width;
> > -	fse->max_width = fse->min_width;
> > -	fse->min_height = supported_modes[fse->index].height;
> > -	fse->max_height = fse->min_height;
> > +		fse->min_width = supported_modes[fse->index].width;
> > +		fse->max_width = fse->min_width;
> > +		fse->min_height = supported_modes[fse->index].height;
> > +		fse->max_height = fse->min_height;
> > +	}
> >
> >  	return 0;
> >  }
> > @@ -801,9 +829,17 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> >  	struct imx219 *imx219 = to_imx219(sd);
> >  	const struct imx219_mode *mode;
> >  	struct v4l2_mbus_framefmt *format;
> > +	struct v4l2_rect *compose;
> >  	struct v4l2_rect *crop;
> >  	unsigned int bin_h, bin_v;
> >
> > +	/*
> > +	 * The driver is mode-based, the format can be set on the source pad
> > +	 * only.
> > +	 */
> > +	if (fmt->pad != IMX219_PAD_SOURCE)
> > +		return v4l2_subdev_get_fmt(sd, state, fmt);
> > +
> >  	/*
> >  	 * Adjust the requested format to match the closest mode. The Bayer
> >  	 * order varies with flips.
> > @@ -822,22 +858,51 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> >  	fmt->format.quantization = V4L2_QUANTIZATION_FULL_RANGE;
> >  	fmt->format.xfer_func = V4L2_XFER_FUNC_NONE;
> >
> > -	format = v4l2_subdev_state_get_format(state, 0);
> > +	/* Propagate the format through the sensor. */
> > +
> > +	/* The image pad models the pixel array, and thus has a fixed size. */
> > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_IMAGE);
> >  	*format = fmt->format;
>
> Is this assignment needed ?
>
> Isn't 'fmt' meant to be applied at pad #0 ? Also, you overwrite the
> code and size below, do the rest of the 'struct v4l2_mbus_framefmt'
> fields apply to pad #1 (field, colorspace, quantization etc ? If pad
> #1 represents the pixel array, I don't think they do).
>
> Also, can't the pad #1 format be initialized by .init_state() and never
> touched again ?
>
>
> > +	format->code = IMX219_NATIVE_FORMAT;
> > +	format->width = IMX219_NATIVE_WIDTH;
> > +	format->height = IMX219_NATIVE_HEIGHT;
> >
> >  	/*
> >  	 * Use binning to maximize the crop rectangle size, and centre it in the
> >  	 * sensor.
> >  	 */
> > -	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / format->width, 2U);
> > -	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / format->height, 2U);
> > +	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / fmt->format.width, 2U);
> > +	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / fmt->format.height, 2U);
> >
> > -	crop = v4l2_subdev_state_get_crop(state, 0);
> > -	crop->width = format->width * bin_h;
> > -	crop->height = format->height * bin_v;
> > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > +	crop->width = fmt->format.width * bin_h;
> > +	crop->height = fmt->format.height * bin_v;
> >  	crop->left = (IMX219_NATIVE_WIDTH - crop->width) / 2;
> >  	crop->top = (IMX219_NATIVE_HEIGHT - crop->height) / 2;
>
> This is no different than before, but I now wonder if VGA is actually
> obtained by cropping down to 1280x960 and then by a 2x2 binning, or is
> there a 4x4 binning mode. I presume this is correct though, as this has been
> validated by many people.
>
> >
> > +	/*
> > +	 * The compose rectangle models binning, its size is the sensor output
> > +	 * size.
> > +	 */
> > +	compose = v4l2_subdev_state_get_compose(state, IMX219_PAD_IMAGE);
> > +	compose->left = 0;
> > +	compose->top = 0;
> > +	compose->width = fmt->format.width;
> > +	compose->height = fmt->format.height;
> > +
> > +	/*
> > +	 * No mode use digital crop, the source pad crop rectangle size and
> > +	 * format are thus identical to the image pad compose rectangle.
> > +	 */
> > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE);
> > +	crop->left = 0;
> > +	crop->top = 0;
> > +	crop->width = fmt->format.width;
> > +	crop->height = fmt->format.height;
> > +
> > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > +	*format = fmt->format;
> > +
> >  	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> >  		int exposure_max;
> >  		int exposure_def;
> > @@ -874,13 +939,13 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> >  				struct v4l2_subdev_state *state,
> >  				struct v4l2_subdev_selection *sel)
> >  {
> > -	switch (sel->target) {
> > -	case V4L2_SEL_TGT_CROP: {
> > -		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > -		return 0;
> > -	}
> > +	struct v4l2_rect *compose;
> >
> > +	switch (sel->target) {
> >  	case V4L2_SEL_TGT_NATIVE_SIZE:
> > +		if (sel->pad != IMX219_PAD_IMAGE)
> > +			return -EINVAL;
> > +
> >  		sel->r.top = 0;
> >  		sel->r.left = 0;
> >  		sel->r.width = IMX219_NATIVE_WIDTH;
> > @@ -890,11 +955,35 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> >
> >  	case V4L2_SEL_TGT_CROP_DEFAULT:
> >  	case V4L2_SEL_TGT_CROP_BOUNDS:
> > -		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > -		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > -		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > -		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > +		switch (sel->pad) {
> > +		case IMX219_PAD_IMAGE:
> > +			sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > +			sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > +			sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > +			sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > +			return 0;
> >
> > +		case IMX219_PAD_SOURCE:
> > +			compose = v4l2_subdev_state_get_compose(state,
> > +								IMX219_PAD_IMAGE);
> > +			sel->r.top = 0;
> > +			sel->r.left = 0;
> > +			sel->r.width = compose->width;
> > +			sel->r.height = compose->height;
> > +			return 0;
> > +		}
> > +
> > +		break;
> > +
> > +	case V4L2_SEL_TGT_CROP:
> > +		sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
> > +		return 0;
> > +
> > +	case V4L2_SEL_TGT_COMPOSE:
> > +		if (sel->pad != IMX219_PAD_IMAGE)
> > +			return -EINVAL;
> > +
> > +		sel->r = *v4l2_subdev_state_get_compose(state, sel->pad);
> >  		return 0;
>
> Do we need to support TGT_COMPOSE_BOUNDS for PAD_IMAGE ? I would have
> suggested V4L2_SEL_TGT_COMPOSE_DEFAULT too, but according to the spec
> it does not apply to subdevices.
>
> >  	}
> >
> > @@ -906,7 +995,7 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> >  {
> >  	struct v4l2_subdev_format fmt = {
> >  		.which = V4L2_SUBDEV_FORMAT_TRY,
> > -		.pad = 0,
> > +		.pad = IMX219_PAD_SOURCE,
> >  		.format = {
> >  			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
> >  			.width = supported_modes[0].width,
>
> Why not intialize pad#1 format here an never touch it again ? Should
> also the pad#1 crop and compose rectangles and pad#0 crop be
> initialized here ?
>
> > @@ -1174,10 +1263,18 @@ static int imx219_probe(struct i2c_client *client)
> >  			    V4L2_SUBDEV_FL_HAS_EVENTS;
> >  	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> >
> > -	/* Initialize source pad */
> > -	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
> > +	/*
> > +	 * Initialize the pads. To preserve backward compatibility with
> > +	 * userspace that used the sensor before the introduction of the
> > +	 * internal image pad, the external source pad is numbered 0 and the
> > +	 * internal image pad numbered 1.
> > +	 */
> > +	imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> > +	imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
> > +					     | MEDIA_PAD_FL_INTERNAL;
> >
> > -	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
> > +	ret = media_entity_pads_init(&imx219->sd.entity,
> > +				     ARRAY_SIZE(imx219->pads), imx219->pads);
> >  	if (ret) {
> >  		dev_err(dev, "failed to init entity pads: %d\n", ret);
> >  		goto error_handler_free;
> > --
> > Regards,
> >
> > Laurent Pinchart
> >
> >
>
Laurent Pinchart March 4, 2024, 3:14 p.m. UTC | #3
Hi Jacopo,

On Mon, Mar 04, 2024 at 10:38:12AM +0100, Jacopo Mondi wrote:
> On Mon, Mar 04, 2024 at 10:13:47AM +0100, Jacopo Mondi wrote:
> > On Fri, Mar 01, 2024 at 11:32:17PM +0200, Laurent Pinchart wrote:
> > > Use the newly added internal pad API to expose the internal
> > > configuration of the sensor to userspace in a standard manner. This also
> > > paves the way for adding support for embedded data with an additional
> > > internal pad.
> > >
> > > To maintain compatibility with existing userspace that may operate on
> > > pad 0 unconditionally, keep the source pad numbered 0 and number the
> > > internal image pad 1.
> > >
> > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > > ---
> > >  drivers/media/i2c/imx219.c | 169 +++++++++++++++++++++++++++++--------
> > >  1 file changed, 133 insertions(+), 36 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > > index 3878da50860e..817bf192e4d9 100644
> > > --- a/drivers/media/i2c/imx219.c
> > > +++ b/drivers/media/i2c/imx219.c
> > > @@ -140,6 +140,7 @@
> > >  #define IMX219_DEFAULT_LINK_FREQ_4LANE	363000000
> > >
> > >  /* IMX219 native and active pixel array size. */
> > > +#define IMX219_NATIVE_FORMAT		MEDIA_BUS_FMT_SRGGB10_1X10
> > >  #define IMX219_NATIVE_WIDTH		3296U
> > >  #define IMX219_NATIVE_HEIGHT		2480U
> > >  #define IMX219_PIXEL_ARRAY_LEFT		8U
> > > @@ -312,9 +313,15 @@ static const struct imx219_mode supported_modes[] = {
> > >  	},
> > >  };
> > >
> > > +enum imx219_pad_ids {
> > > +	IMX219_PAD_SOURCE,
> > > +	IMX219_PAD_IMAGE,
> >
> > Feels a bit weird for the internal source pad to be named "Image" as
> > it will (if I understand correctly) host both the image and metadata
> > streams.
> >
> > However, I have an hard time proposing a different name, but we should
> > find something that should be used in all drivers ported to this new
> > API.
> >
> > Enough with bikeshedding anyway, this is a tiny detail.
> 
> Now that I've read 5/15 I now understand why this is called "IMAGE" :)

:-)

> > > +	IMX219_NUM_PADS,
> > > +};
> > > +
> > >  struct imx219 {
> > >  	struct v4l2_subdev sd;
> > > -	struct media_pad pad;
> > > +	struct media_pad pads[IMX219_NUM_PADS];
> > >
> > >  	struct regmap *regmap;
> > >  	struct clk *xclk; /* system clock to IMX219 */
> > > @@ -374,7 +381,7 @@ static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
> > >  	int ret = 0;
> > >
> > >  	state = v4l2_subdev_get_locked_active_state(&imx219->sd);
> > > -	format = v4l2_subdev_state_get_format(state, 0);
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > >
> > >  	if (ctrl->id == V4L2_CID_VBLANK) {
> > >  		int exposure_max, exposure_def;
> > > @@ -593,8 +600,8 @@ static int imx219_set_framefmt(struct imx219 *imx219,
> > >  	u64 bin_h, bin_v;
> > >  	int ret = 0;
> > >
> > > -	format = v4l2_subdev_state_get_format(state, 0);
> > > -	crop = v4l2_subdev_state_get_crop(state, 0);
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > >
> > >  	switch (format->code) {
> > >  	case MEDIA_BUS_FMT_SRGGB8_1X8:
> > > @@ -764,10 +771,25 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
> > >  {
> > >  	struct imx219 *imx219 = to_imx219(sd);
> > >
> > > -	if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > -		return -EINVAL;
> > > +	if (code->pad == IMX219_PAD_IMAGE) {
> > > +		/* The internal image pad is hardwired to the native format. */
> > > +		if (code->index)
> > > +			return -EINVAL;
> > >
> > > -	code->code = imx219_get_format_code(imx219, imx219_mbus_formats[code->index * 4]);
> > > +		code->code = IMX219_NATIVE_FORMAT;
> >
> > If you return 0 here you can spare the else {} branch. Same in the
> > function below.
> >
> 
> You're reworking this in 5/15, so no need to change this and cause
> rebase conflicts.

It's true that I'm reworking it further in 05/15, but I think the change
here still makes sense, as it updates the driver to support the internal
pad properly. Beside, if I were to drop this change, then I would get a
rebase conflict :-)

> > > +	} else {
> > > +		/*
> > > +		 * On the source pad, the sensor supports multiple raw formats
> > > +		 * with different bit depths.
> > > +		 */
> > > +		u32 format;
> > > +
> > > +		if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > +			return -EINVAL;
> > > +
> > > +		format = imx219_mbus_formats[code->index * 4];
> > > +		code->code = imx219_get_format_code(imx219, format);
> > > +	}
> > >
> > >  	return 0;
> > >  }
> > > @@ -777,19 +799,25 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > >  				  struct v4l2_subdev_frame_size_enum *fse)
> > >  {
> > >  	struct imx219 *imx219 = to_imx219(sd);
> > > -	u32 code;
> > >
> > > -	if (fse->index >= ARRAY_SIZE(supported_modes))
> > > -		return -EINVAL;
> > > +	if (fse->pad == IMX219_PAD_IMAGE) {
> > > +		if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
> > > +			return -EINVAL;
> > >
> > > -	code = imx219_get_format_code(imx219, fse->code);
> > > -	if (fse->code != code)
> > > -		return -EINVAL;
> > > +		fse->min_width = IMX219_NATIVE_WIDTH;
> > > +		fse->max_width = IMX219_NATIVE_WIDTH;
> > > +		fse->min_height = IMX219_NATIVE_HEIGHT;
> > > +		fse->max_height = IMX219_NATIVE_HEIGHT;
> > > +	} else {
> > > +		if (fse->code != imx219_get_format_code(imx219, fse->code) ||
> > > +		    fse->index >= ARRAY_SIZE(supported_modes))
> > > +			return -EINVAL;
> > >
> > > -	fse->min_width = supported_modes[fse->index].width;
> > > -	fse->max_width = fse->min_width;
> > > -	fse->min_height = supported_modes[fse->index].height;
> > > -	fse->max_height = fse->min_height;
> > > +		fse->min_width = supported_modes[fse->index].width;
> > > +		fse->max_width = fse->min_width;
> > > +		fse->min_height = supported_modes[fse->index].height;
> > > +		fse->max_height = fse->min_height;
> > > +	}
> > >
> > >  	return 0;
> > >  }
> > > @@ -801,9 +829,17 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > >  	struct imx219 *imx219 = to_imx219(sd);
> > >  	const struct imx219_mode *mode;
> > >  	struct v4l2_mbus_framefmt *format;
> > > +	struct v4l2_rect *compose;
> > >  	struct v4l2_rect *crop;
> > >  	unsigned int bin_h, bin_v;
> > >
> > > +	/*
> > > +	 * The driver is mode-based, the format can be set on the source pad
> > > +	 * only.
> > > +	 */
> > > +	if (fmt->pad != IMX219_PAD_SOURCE)
> > > +		return v4l2_subdev_get_fmt(sd, state, fmt);
> > > +
> > >  	/*
> > >  	 * Adjust the requested format to match the closest mode. The Bayer
> > >  	 * order varies with flips.
> > > @@ -822,22 +858,51 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > >  	fmt->format.quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > >  	fmt->format.xfer_func = V4L2_XFER_FUNC_NONE;
> > >
> > > -	format = v4l2_subdev_state_get_format(state, 0);
> > > +	/* Propagate the format through the sensor. */
> > > +
> > > +	/* The image pad models the pixel array, and thus has a fixed size. */
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_IMAGE);
> > >  	*format = fmt->format;
> >
> > Is this assignment needed ?
> >
> > Isn't 'fmt' meant to be applied at pad #0 ? Also, you overwrite the
> > code and size below, do the rest of the 'struct v4l2_mbus_framefmt'
> > fields apply to pad #1 (field, colorspace, quantization etc ? If pad
> > #1 represents the pixel array, I don't think they do).

It's a shortcut to avoid setting field, colorspace, ycbcr_enc,
quantization and xfer_func manually, as there's set a few lines above in
fmt. I can set the fields manually if you prefer.

> > Also, can't the pad #1 format be initialized by .init_state() and never
> > touched again ?

They could, but then .init_state() couldn't be implemented by simply
calling imx219_set_pad_format(). I think it is clearer to store all the
format setting logic in one place, especially when adding support for
the embedded data stream.

> > > +	format->code = IMX219_NATIVE_FORMAT;
> > > +	format->width = IMX219_NATIVE_WIDTH;
> > > +	format->height = IMX219_NATIVE_HEIGHT;
> > >
> > >  	/*
> > >  	 * Use binning to maximize the crop rectangle size, and centre it in the
> > >  	 * sensor.
> > >  	 */
> > > -	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / format->width, 2U);
> > > -	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / format->height, 2U);
> > > +	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / fmt->format.width, 2U);
> > > +	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / fmt->format.height, 2U);
> > >
> > > -	crop = v4l2_subdev_state_get_crop(state, 0);
> > > -	crop->width = format->width * bin_h;
> > > -	crop->height = format->height * bin_v;
> > > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > > +	crop->width = fmt->format.width * bin_h;
> > > +	crop->height = fmt->format.height * bin_v;
> > >  	crop->left = (IMX219_NATIVE_WIDTH - crop->width) / 2;
> > >  	crop->top = (IMX219_NATIVE_HEIGHT - crop->height) / 2;
> >
> > This is no different than before, but I now wonder if VGA is actually
> > obtained by cropping down to 1280x960 and then by a 2x2 binning, or is
> > there a 4x4 binning mode. I presume this is correct though, as this has been
> > validated by many people.

It would be worth experimenting with the /4 binning mode.

> > > +	/*
> > > +	 * The compose rectangle models binning, its size is the sensor output
> > > +	 * size.
> > > +	 */
> > > +	compose = v4l2_subdev_state_get_compose(state, IMX219_PAD_IMAGE);
> > > +	compose->left = 0;
> > > +	compose->top = 0;
> > > +	compose->width = fmt->format.width;
> > > +	compose->height = fmt->format.height;
> > > +
> > > +	/*
> > > +	 * No mode use digital crop, the source pad crop rectangle size and
> > > +	 * format are thus identical to the image pad compose rectangle.
> > > +	 */
> > > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE);
> > > +	crop->left = 0;
> > > +	crop->top = 0;
> > > +	crop->width = fmt->format.width;
> > > +	crop->height = fmt->format.height;
> > > +
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > +	*format = fmt->format;
> > > +
> > >  	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> > >  		int exposure_max;
> > >  		int exposure_def;
> > > @@ -874,13 +939,13 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > >  				struct v4l2_subdev_state *state,
> > >  				struct v4l2_subdev_selection *sel)
> > >  {
> > > -	switch (sel->target) {
> > > -	case V4L2_SEL_TGT_CROP: {
> > > -		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > -		return 0;
> > > -	}
> > > +	struct v4l2_rect *compose;
> > >
> > > +	switch (sel->target) {
> > >  	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > +		if (sel->pad != IMX219_PAD_IMAGE)
> > > +			return -EINVAL;
> > > +
> > >  		sel->r.top = 0;
> > >  		sel->r.left = 0;
> > >  		sel->r.width = IMX219_NATIVE_WIDTH;
> > > @@ -890,11 +955,35 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > >
> > >  	case V4L2_SEL_TGT_CROP_DEFAULT:
> > >  	case V4L2_SEL_TGT_CROP_BOUNDS:
> > > -		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > -		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > -		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > -		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > +		switch (sel->pad) {
> > > +		case IMX219_PAD_IMAGE:
> > > +			sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > +			sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > +			sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > +			sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > +			return 0;
> > >
> > > +		case IMX219_PAD_SOURCE:
> > > +			compose = v4l2_subdev_state_get_compose(state,
> > > +								IMX219_PAD_IMAGE);
> > > +			sel->r.top = 0;
> > > +			sel->r.left = 0;
> > > +			sel->r.width = compose->width;
> > > +			sel->r.height = compose->height;
> > > +			return 0;
> > > +		}
> > > +
> > > +		break;
> > > +
> > > +	case V4L2_SEL_TGT_CROP:
> > > +		sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
> > > +		return 0;
> > > +
> > > +	case V4L2_SEL_TGT_COMPOSE:
> > > +		if (sel->pad != IMX219_PAD_IMAGE)
> > > +			return -EINVAL;
> > > +
> > > +		sel->r = *v4l2_subdev_state_get_compose(state, sel->pad);
> > >  		return 0;
> >
> > Do we need to support TGT_COMPOSE_BOUNDS for PAD_IMAGE ? I would have
> > suggested V4L2_SEL_TGT_COMPOSE_DEFAULT too, but according to the spec
> > it does not apply to subdevices.

Good question. V4L2_SEL_TGT_COMPOSE_BOUNDS is a bit under-documented for
V4L2 subdevs. I wonder if it wouldn't be simpler for drivers to not
implement it when the compose bounds are identical to the crop rectangle
size, as that could be considered a default ?

> > >  	}
> > >
> > > @@ -906,7 +995,7 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> > >  {
> > >  	struct v4l2_subdev_format fmt = {
> > >  		.which = V4L2_SUBDEV_FORMAT_TRY,
> > > -		.pad = 0,
> > > +		.pad = IMX219_PAD_SOURCE,
> > >  		.format = {
> > >  			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
> > >  			.width = supported_modes[0].width,
> >
> > Why not intialize pad#1 format here an never touch it again ? Should
> > also the pad#1 crop and compose rectangles and pad#0 crop be
> > initialized here ?

As written above, I think it's cleaner to have all the format-related
constraints in one place, especially with support for embedded data. It
may be a style preference, I'm not sure.

> > > @@ -1174,10 +1263,18 @@ static int imx219_probe(struct i2c_client *client)
> > >  			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > >  	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > >
> > > -	/* Initialize source pad */
> > > -	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > +	/*
> > > +	 * Initialize the pads. To preserve backward compatibility with
> > > +	 * userspace that used the sensor before the introduction of the
> > > +	 * internal image pad, the external source pad is numbered 0 and the
> > > +	 * internal image pad numbered 1.
> > > +	 */
> > > +	imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> > > +	imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
> > > +					     | MEDIA_PAD_FL_INTERNAL;
> > >
> > > -	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
> > > +	ret = media_entity_pads_init(&imx219->sd.entity,
> > > +				     ARRAY_SIZE(imx219->pads), imx219->pads);
> > >  	if (ret) {
> > >  		dev_err(dev, "failed to init entity pads: %d\n", ret);
> > >  		goto error_handler_free;
Jacopo Mondi March 4, 2024, 3:57 p.m. UTC | #4
Hi Laurent

On Mon, Mar 04, 2024 at 05:14:26PM +0200, Laurent Pinchart wrote:
> Hi Jacopo,
>
> On Mon, Mar 04, 2024 at 10:38:12AM +0100, Jacopo Mondi wrote:
> > On Mon, Mar 04, 2024 at 10:13:47AM +0100, Jacopo Mondi wrote:
> > > On Fri, Mar 01, 2024 at 11:32:17PM +0200, Laurent Pinchart wrote:
> > > > Use the newly added internal pad API to expose the internal
> > > > configuration of the sensor to userspace in a standard manner. This also
> > > > paves the way for adding support for embedded data with an additional
> > > > internal pad.
> > > >
> > > > To maintain compatibility with existing userspace that may operate on
> > > > pad 0 unconditionally, keep the source pad numbered 0 and number the
> > > > internal image pad 1.
> > > >
> > > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > > > ---
> > > >  drivers/media/i2c/imx219.c | 169 +++++++++++++++++++++++++++++--------
> > > >  1 file changed, 133 insertions(+), 36 deletions(-)
> > > >
> > > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > > > index 3878da50860e..817bf192e4d9 100644
> > > > --- a/drivers/media/i2c/imx219.c
> > > > +++ b/drivers/media/i2c/imx219.c
> > > > @@ -140,6 +140,7 @@
> > > >  #define IMX219_DEFAULT_LINK_FREQ_4LANE	363000000
> > > >
> > > >  /* IMX219 native and active pixel array size. */
> > > > +#define IMX219_NATIVE_FORMAT		MEDIA_BUS_FMT_SRGGB10_1X10
> > > >  #define IMX219_NATIVE_WIDTH		3296U
> > > >  #define IMX219_NATIVE_HEIGHT		2480U
> > > >  #define IMX219_PIXEL_ARRAY_LEFT		8U
> > > > @@ -312,9 +313,15 @@ static const struct imx219_mode supported_modes[] = {
> > > >  	},
> > > >  };
> > > >
> > > > +enum imx219_pad_ids {
> > > > +	IMX219_PAD_SOURCE,
> > > > +	IMX219_PAD_IMAGE,
> > >
> > > Feels a bit weird for the internal source pad to be named "Image" as
> > > it will (if I understand correctly) host both the image and metadata
> > > streams.
> > >
> > > However, I have an hard time proposing a different name, but we should
> > > find something that should be used in all drivers ported to this new
> > > API.
> > >
> > > Enough with bikeshedding anyway, this is a tiny detail.
> >
> > Now that I've read 5/15 I now understand why this is called "IMAGE" :)
>
> :-)
>
> > > > +	IMX219_NUM_PADS,
> > > > +};
> > > > +
> > > >  struct imx219 {
> > > >  	struct v4l2_subdev sd;
> > > > -	struct media_pad pad;
> > > > +	struct media_pad pads[IMX219_NUM_PADS];
> > > >
> > > >  	struct regmap *regmap;
> > > >  	struct clk *xclk; /* system clock to IMX219 */
> > > > @@ -374,7 +381,7 @@ static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
> > > >  	int ret = 0;
> > > >
> > > >  	state = v4l2_subdev_get_locked_active_state(&imx219->sd);
> > > > -	format = v4l2_subdev_state_get_format(state, 0);
> > > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > >
> > > >  	if (ctrl->id == V4L2_CID_VBLANK) {
> > > >  		int exposure_max, exposure_def;
> > > > @@ -593,8 +600,8 @@ static int imx219_set_framefmt(struct imx219 *imx219,
> > > >  	u64 bin_h, bin_v;
> > > >  	int ret = 0;
> > > >
> > > > -	format = v4l2_subdev_state_get_format(state, 0);
> > > > -	crop = v4l2_subdev_state_get_crop(state, 0);
> > > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > > >
> > > >  	switch (format->code) {
> > > >  	case MEDIA_BUS_FMT_SRGGB8_1X8:
> > > > @@ -764,10 +771,25 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
> > > >  {
> > > >  	struct imx219 *imx219 = to_imx219(sd);
> > > >
> > > > -	if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > > -		return -EINVAL;
> > > > +	if (code->pad == IMX219_PAD_IMAGE) {
> > > > +		/* The internal image pad is hardwired to the native format. */
> > > > +		if (code->index)
> > > > +			return -EINVAL;
> > > >
> > > > -	code->code = imx219_get_format_code(imx219, imx219_mbus_formats[code->index * 4]);
> > > > +		code->code = IMX219_NATIVE_FORMAT;
> > >
> > > If you return 0 here you can spare the else {} branch. Same in the
> > > function below.
> > >
> >
> > You're reworking this in 5/15, so no need to change this and cause
> > rebase conflicts.
>
> It's true that I'm reworking it further in 05/15, but I think the change
> here still makes sense, as it updates the driver to support the internal
> pad properly. Beside, if I were to drop this change, then I would get a
> rebase conflict :-)
>

I was suggesting to ignore my comment, not to drop the change ;)

> > > > +	} else {
> > > > +		/*
> > > > +		 * On the source pad, the sensor supports multiple raw formats
> > > > +		 * with different bit depths.
> > > > +		 */
> > > > +		u32 format;
> > > > +
> > > > +		if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > > +			return -EINVAL;
> > > > +
> > > > +		format = imx219_mbus_formats[code->index * 4];
> > > > +		code->code = imx219_get_format_code(imx219, format);
> > > > +	}
> > > >
> > > >  	return 0;
> > > >  }
> > > > @@ -777,19 +799,25 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > > >  				  struct v4l2_subdev_frame_size_enum *fse)
> > > >  {
> > > >  	struct imx219 *imx219 = to_imx219(sd);
> > > > -	u32 code;
> > > >
> > > > -	if (fse->index >= ARRAY_SIZE(supported_modes))
> > > > -		return -EINVAL;
> > > > +	if (fse->pad == IMX219_PAD_IMAGE) {
> > > > +		if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
> > > > +			return -EINVAL;
> > > >
> > > > -	code = imx219_get_format_code(imx219, fse->code);
> > > > -	if (fse->code != code)
> > > > -		return -EINVAL;
> > > > +		fse->min_width = IMX219_NATIVE_WIDTH;
> > > > +		fse->max_width = IMX219_NATIVE_WIDTH;
> > > > +		fse->min_height = IMX219_NATIVE_HEIGHT;
> > > > +		fse->max_height = IMX219_NATIVE_HEIGHT;
> > > > +	} else {
> > > > +		if (fse->code != imx219_get_format_code(imx219, fse->code) ||
> > > > +		    fse->index >= ARRAY_SIZE(supported_modes))
> > > > +			return -EINVAL;
> > > >
> > > > -	fse->min_width = supported_modes[fse->index].width;
> > > > -	fse->max_width = fse->min_width;
> > > > -	fse->min_height = supported_modes[fse->index].height;
> > > > -	fse->max_height = fse->min_height;
> > > > +		fse->min_width = supported_modes[fse->index].width;
> > > > +		fse->max_width = fse->min_width;
> > > > +		fse->min_height = supported_modes[fse->index].height;
> > > > +		fse->max_height = fse->min_height;
> > > > +	}
> > > >
> > > >  	return 0;
> > > >  }
> > > > @@ -801,9 +829,17 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > > >  	struct imx219 *imx219 = to_imx219(sd);
> > > >  	const struct imx219_mode *mode;
> > > >  	struct v4l2_mbus_framefmt *format;
> > > > +	struct v4l2_rect *compose;
> > > >  	struct v4l2_rect *crop;
> > > >  	unsigned int bin_h, bin_v;
> > > >
> > > > +	/*
> > > > +	 * The driver is mode-based, the format can be set on the source pad
> > > > +	 * only.
> > > > +	 */
> > > > +	if (fmt->pad != IMX219_PAD_SOURCE)
> > > > +		return v4l2_subdev_get_fmt(sd, state, fmt);
> > > > +
> > > >  	/*
> > > >  	 * Adjust the requested format to match the closest mode. The Bayer
> > > >  	 * order varies with flips.
> > > > @@ -822,22 +858,51 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > > >  	fmt->format.quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > >  	fmt->format.xfer_func = V4L2_XFER_FUNC_NONE;
> > > >
> > > > -	format = v4l2_subdev_state_get_format(state, 0);
> > > > +	/* Propagate the format through the sensor. */
> > > > +
> > > > +	/* The image pad models the pixel array, and thus has a fixed size. */
> > > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_IMAGE);
> > > >  	*format = fmt->format;
> > >
> > > Is this assignment needed ?
> > >
> > > Isn't 'fmt' meant to be applied at pad #0 ? Also, you overwrite the
> > > code and size below, do the rest of the 'struct v4l2_mbus_framefmt'
> > > fields apply to pad #1 (field, colorspace, quantization etc ? If pad
> > > #1 represents the pixel array, I don't think they do).
>
> It's a shortcut to avoid setting field, colorspace, ycbcr_enc,
> quantization and xfer_func manually, as there's set a few lines above in
> fmt. I can set the fields manually if you prefer.
>

Yes, and my question was related to the fact those information as
received from userspace might not be valid for pad #1, but as they are
corrected a few lines above, and are not different between pad #0 and
pad #1, I think the version you have is fine

> > > Also, can't the pad #1 format be initialized by .init_state() and never
> > > touched again ?
>
> They could, but then .init_state() couldn't be implemented by simply
> calling imx219_set_pad_format(). I think it is clearer to store all the
> format setting logic in one place, especially when adding support for
> the embedded data stream.
>

Ack then!

> > > > +	format->code = IMX219_NATIVE_FORMAT;
> > > > +	format->width = IMX219_NATIVE_WIDTH;
> > > > +	format->height = IMX219_NATIVE_HEIGHT;
> > > >
> > > >  	/*
> > > >  	 * Use binning to maximize the crop rectangle size, and centre it in the
> > > >  	 * sensor.
> > > >  	 */
> > > > -	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / format->width, 2U);
> > > > -	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / format->height, 2U);
> > > > +	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / fmt->format.width, 2U);
> > > > +	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / fmt->format.height, 2U);
> > > >
> > > > -	crop = v4l2_subdev_state_get_crop(state, 0);
> > > > -	crop->width = format->width * bin_h;
> > > > -	crop->height = format->height * bin_v;
> > > > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > > > +	crop->width = fmt->format.width * bin_h;
> > > > +	crop->height = fmt->format.height * bin_v;
> > > >  	crop->left = (IMX219_NATIVE_WIDTH - crop->width) / 2;
> > > >  	crop->top = (IMX219_NATIVE_HEIGHT - crop->height) / 2;
> > >
> > > This is no different than before, but I now wonder if VGA is actually
> > > obtained by cropping down to 1280x960 and then by a 2x2 binning, or is
> > > there a 4x4 binning mode. I presume this is correct though, as this has been
> > > validated by many people.
>
> It would be worth experimenting with the /4 binning mode.
>

Maybe not as part of this series

> > > > +	/*
> > > > +	 * The compose rectangle models binning, its size is the sensor output
> > > > +	 * size.
> > > > +	 */
> > > > +	compose = v4l2_subdev_state_get_compose(state, IMX219_PAD_IMAGE);
> > > > +	compose->left = 0;
> > > > +	compose->top = 0;
> > > > +	compose->width = fmt->format.width;
> > > > +	compose->height = fmt->format.height;
> > > > +
> > > > +	/*
> > > > +	 * No mode use digital crop, the source pad crop rectangle size and
> > > > +	 * format are thus identical to the image pad compose rectangle.
> > > > +	 */
> > > > +	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE);
> > > > +	crop->left = 0;
> > > > +	crop->top = 0;
> > > > +	crop->width = fmt->format.width;
> > > > +	crop->height = fmt->format.height;
> > > > +
> > > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > > +	*format = fmt->format;
> > > > +
> > > >  	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> > > >  		int exposure_max;
> > > >  		int exposure_def;
> > > > @@ -874,13 +939,13 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > > >  				struct v4l2_subdev_state *state,
> > > >  				struct v4l2_subdev_selection *sel)
> > > >  {
> > > > -	switch (sel->target) {
> > > > -	case V4L2_SEL_TGT_CROP: {
> > > > -		sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > > -		return 0;
> > > > -	}
> > > > +	struct v4l2_rect *compose;
> > > >
> > > > +	switch (sel->target) {
> > > >  	case V4L2_SEL_TGT_NATIVE_SIZE:
> > > > +		if (sel->pad != IMX219_PAD_IMAGE)
> > > > +			return -EINVAL;
> > > > +
> > > >  		sel->r.top = 0;
> > > >  		sel->r.left = 0;
> > > >  		sel->r.width = IMX219_NATIVE_WIDTH;
> > > > @@ -890,11 +955,35 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > > >
> > > >  	case V4L2_SEL_TGT_CROP_DEFAULT:
> > > >  	case V4L2_SEL_TGT_CROP_BOUNDS:
> > > > -		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > > -		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > > -		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > > -		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > > +		switch (sel->pad) {
> > > > +		case IMX219_PAD_IMAGE:
> > > > +			sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > > +			sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > > +			sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > > +			sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > > +			return 0;
> > > >
> > > > +		case IMX219_PAD_SOURCE:
> > > > +			compose = v4l2_subdev_state_get_compose(state,
> > > > +								IMX219_PAD_IMAGE);
> > > > +			sel->r.top = 0;
> > > > +			sel->r.left = 0;
> > > > +			sel->r.width = compose->width;
> > > > +			sel->r.height = compose->height;
> > > > +			return 0;
> > > > +		}
> > > > +
> > > > +		break;
> > > > +
> > > > +	case V4L2_SEL_TGT_CROP:
> > > > +		sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
> > > > +		return 0;
> > > > +
> > > > +	case V4L2_SEL_TGT_COMPOSE:
> > > > +		if (sel->pad != IMX219_PAD_IMAGE)
> > > > +			return -EINVAL;
> > > > +
> > > > +		sel->r = *v4l2_subdev_state_get_compose(state, sel->pad);
> > > >  		return 0;
> > >
> > > Do we need to support TGT_COMPOSE_BOUNDS for PAD_IMAGE ? I would have
> > > suggested V4L2_SEL_TGT_COMPOSE_DEFAULT too, but according to the spec
> > > it does not apply to subdevices.
>
> Good question. V4L2_SEL_TGT_COMPOSE_BOUNDS is a bit under-documented for
> V4L2 subdevs. I wonder if it wouldn't be simpler for drivers to not
> implement it when the compose bounds are identical to the crop rectangle
> size, as that could be considered a default ?
>

I'm fine with that, it should maybe be documented

> > > >  	}
> > > >
> > > > @@ -906,7 +995,7 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> > > >  {
> > > >  	struct v4l2_subdev_format fmt = {
> > > >  		.which = V4L2_SUBDEV_FORMAT_TRY,
> > > > -		.pad = 0,
> > > > +		.pad = IMX219_PAD_SOURCE,
> > > >  		.format = {
> > > >  			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
> > > >  			.width = supported_modes[0].width,
> > >
> > > Why not intialize pad#1 format here an never touch it again ? Should
> > > also the pad#1 crop and compose rectangles and pad#0 crop be
> > > initialized here ?
>
> As written above, I think it's cleaner to have all the format-related
> constraints in one place, especially with support for embedded data. It
> may be a style preference, I'm not sure.
>

Fine with me!

Thanks
  j

> > > > @@ -1174,10 +1263,18 @@ static int imx219_probe(struct i2c_client *client)
> > > >  			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > >  	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > >
> > > > -	/* Initialize source pad */
> > > > -	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > +	/*
> > > > +	 * Initialize the pads. To preserve backward compatibility with
> > > > +	 * userspace that used the sensor before the introduction of the
> > > > +	 * internal image pad, the external source pad is numbered 0 and the
> > > > +	 * internal image pad numbered 1.
> > > > +	 */
> > > > +	imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> > > > +	imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
> > > > +					     | MEDIA_PAD_FL_INTERNAL;
> > > >
> > > > -	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
> > > > +	ret = media_entity_pads_init(&imx219->sd.entity,
> > > > +				     ARRAY_SIZE(imx219->pads), imx219->pads);
> > > >  	if (ret) {
> > > >  		dev_err(dev, "failed to init entity pads: %d\n", ret);
> > > >  		goto error_handler_free;
>
> --
> Regards,
>
> Laurent Pinchart
>
diff mbox series

Patch

diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
index 3878da50860e..817bf192e4d9 100644
--- a/drivers/media/i2c/imx219.c
+++ b/drivers/media/i2c/imx219.c
@@ -140,6 +140,7 @@ 
 #define IMX219_DEFAULT_LINK_FREQ_4LANE	363000000
 
 /* IMX219 native and active pixel array size. */
+#define IMX219_NATIVE_FORMAT		MEDIA_BUS_FMT_SRGGB10_1X10
 #define IMX219_NATIVE_WIDTH		3296U
 #define IMX219_NATIVE_HEIGHT		2480U
 #define IMX219_PIXEL_ARRAY_LEFT		8U
@@ -312,9 +313,15 @@  static const struct imx219_mode supported_modes[] = {
 	},
 };
 
+enum imx219_pad_ids {
+	IMX219_PAD_SOURCE,
+	IMX219_PAD_IMAGE,
+	IMX219_NUM_PADS,
+};
+
 struct imx219 {
 	struct v4l2_subdev sd;
-	struct media_pad pad;
+	struct media_pad pads[IMX219_NUM_PADS];
 
 	struct regmap *regmap;
 	struct clk *xclk; /* system clock to IMX219 */
@@ -374,7 +381,7 @@  static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
 	int ret = 0;
 
 	state = v4l2_subdev_get_locked_active_state(&imx219->sd);
-	format = v4l2_subdev_state_get_format(state, 0);
+	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
 
 	if (ctrl->id == V4L2_CID_VBLANK) {
 		int exposure_max, exposure_def;
@@ -593,8 +600,8 @@  static int imx219_set_framefmt(struct imx219 *imx219,
 	u64 bin_h, bin_v;
 	int ret = 0;
 
-	format = v4l2_subdev_state_get_format(state, 0);
-	crop = v4l2_subdev_state_get_crop(state, 0);
+	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
+	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
 
 	switch (format->code) {
 	case MEDIA_BUS_FMT_SRGGB8_1X8:
@@ -764,10 +771,25 @@  static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
 {
 	struct imx219 *imx219 = to_imx219(sd);
 
-	if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
-		return -EINVAL;
+	if (code->pad == IMX219_PAD_IMAGE) {
+		/* The internal image pad is hardwired to the native format. */
+		if (code->index)
+			return -EINVAL;
 
-	code->code = imx219_get_format_code(imx219, imx219_mbus_formats[code->index * 4]);
+		code->code = IMX219_NATIVE_FORMAT;
+	} else {
+		/*
+		 * On the source pad, the sensor supports multiple raw formats
+		 * with different bit depths.
+		 */
+		u32 format;
+
+		if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
+			return -EINVAL;
+
+		format = imx219_mbus_formats[code->index * 4];
+		code->code = imx219_get_format_code(imx219, format);
+	}
 
 	return 0;
 }
@@ -777,19 +799,25 @@  static int imx219_enum_frame_size(struct v4l2_subdev *sd,
 				  struct v4l2_subdev_frame_size_enum *fse)
 {
 	struct imx219 *imx219 = to_imx219(sd);
-	u32 code;
 
-	if (fse->index >= ARRAY_SIZE(supported_modes))
-		return -EINVAL;
+	if (fse->pad == IMX219_PAD_IMAGE) {
+		if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
+			return -EINVAL;
 
-	code = imx219_get_format_code(imx219, fse->code);
-	if (fse->code != code)
-		return -EINVAL;
+		fse->min_width = IMX219_NATIVE_WIDTH;
+		fse->max_width = IMX219_NATIVE_WIDTH;
+		fse->min_height = IMX219_NATIVE_HEIGHT;
+		fse->max_height = IMX219_NATIVE_HEIGHT;
+	} else {
+		if (fse->code != imx219_get_format_code(imx219, fse->code) ||
+		    fse->index >= ARRAY_SIZE(supported_modes))
+			return -EINVAL;
 
-	fse->min_width = supported_modes[fse->index].width;
-	fse->max_width = fse->min_width;
-	fse->min_height = supported_modes[fse->index].height;
-	fse->max_height = fse->min_height;
+		fse->min_width = supported_modes[fse->index].width;
+		fse->max_width = fse->min_width;
+		fse->min_height = supported_modes[fse->index].height;
+		fse->max_height = fse->min_height;
+	}
 
 	return 0;
 }
@@ -801,9 +829,17 @@  static int imx219_set_pad_format(struct v4l2_subdev *sd,
 	struct imx219 *imx219 = to_imx219(sd);
 	const struct imx219_mode *mode;
 	struct v4l2_mbus_framefmt *format;
+	struct v4l2_rect *compose;
 	struct v4l2_rect *crop;
 	unsigned int bin_h, bin_v;
 
+	/*
+	 * The driver is mode-based, the format can be set on the source pad
+	 * only.
+	 */
+	if (fmt->pad != IMX219_PAD_SOURCE)
+		return v4l2_subdev_get_fmt(sd, state, fmt);
+
 	/*
 	 * Adjust the requested format to match the closest mode. The Bayer
 	 * order varies with flips.
@@ -822,22 +858,51 @@  static int imx219_set_pad_format(struct v4l2_subdev *sd,
 	fmt->format.quantization = V4L2_QUANTIZATION_FULL_RANGE;
 	fmt->format.xfer_func = V4L2_XFER_FUNC_NONE;
 
-	format = v4l2_subdev_state_get_format(state, 0);
+	/* Propagate the format through the sensor. */
+
+	/* The image pad models the pixel array, and thus has a fixed size. */
+	format = v4l2_subdev_state_get_format(state, IMX219_PAD_IMAGE);
 	*format = fmt->format;
+	format->code = IMX219_NATIVE_FORMAT;
+	format->width = IMX219_NATIVE_WIDTH;
+	format->height = IMX219_NATIVE_HEIGHT;
 
 	/*
 	 * Use binning to maximize the crop rectangle size, and centre it in the
 	 * sensor.
 	 */
-	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / format->width, 2U);
-	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / format->height, 2U);
+	bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / fmt->format.width, 2U);
+	bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / fmt->format.height, 2U);
 
-	crop = v4l2_subdev_state_get_crop(state, 0);
-	crop->width = format->width * bin_h;
-	crop->height = format->height * bin_v;
+	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
+	crop->width = fmt->format.width * bin_h;
+	crop->height = fmt->format.height * bin_v;
 	crop->left = (IMX219_NATIVE_WIDTH - crop->width) / 2;
 	crop->top = (IMX219_NATIVE_HEIGHT - crop->height) / 2;
 
+	/*
+	 * The compose rectangle models binning, its size is the sensor output
+	 * size.
+	 */
+	compose = v4l2_subdev_state_get_compose(state, IMX219_PAD_IMAGE);
+	compose->left = 0;
+	compose->top = 0;
+	compose->width = fmt->format.width;
+	compose->height = fmt->format.height;
+
+	/*
+	 * No mode use digital crop, the source pad crop rectangle size and
+	 * format are thus identical to the image pad compose rectangle.
+	 */
+	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE);
+	crop->left = 0;
+	crop->top = 0;
+	crop->width = fmt->format.width;
+	crop->height = fmt->format.height;
+
+	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
+	*format = fmt->format;
+
 	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
 		int exposure_max;
 		int exposure_def;
@@ -874,13 +939,13 @@  static int imx219_get_selection(struct v4l2_subdev *sd,
 				struct v4l2_subdev_state *state,
 				struct v4l2_subdev_selection *sel)
 {
-	switch (sel->target) {
-	case V4L2_SEL_TGT_CROP: {
-		sel->r = *v4l2_subdev_state_get_crop(state, 0);
-		return 0;
-	}
+	struct v4l2_rect *compose;
 
+	switch (sel->target) {
 	case V4L2_SEL_TGT_NATIVE_SIZE:
+		if (sel->pad != IMX219_PAD_IMAGE)
+			return -EINVAL;
+
 		sel->r.top = 0;
 		sel->r.left = 0;
 		sel->r.width = IMX219_NATIVE_WIDTH;
@@ -890,11 +955,35 @@  static int imx219_get_selection(struct v4l2_subdev *sd,
 
 	case V4L2_SEL_TGT_CROP_DEFAULT:
 	case V4L2_SEL_TGT_CROP_BOUNDS:
-		sel->r.top = IMX219_PIXEL_ARRAY_TOP;
-		sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
-		sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
-		sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
+		switch (sel->pad) {
+		case IMX219_PAD_IMAGE:
+			sel->r.top = IMX219_PIXEL_ARRAY_TOP;
+			sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
+			sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
+			sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
+			return 0;
 
+		case IMX219_PAD_SOURCE:
+			compose = v4l2_subdev_state_get_compose(state,
+								IMX219_PAD_IMAGE);
+			sel->r.top = 0;
+			sel->r.left = 0;
+			sel->r.width = compose->width;
+			sel->r.height = compose->height;
+			return 0;
+		}
+
+		break;
+
+	case V4L2_SEL_TGT_CROP:
+		sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
+		return 0;
+
+	case V4L2_SEL_TGT_COMPOSE:
+		if (sel->pad != IMX219_PAD_IMAGE)
+			return -EINVAL;
+
+		sel->r = *v4l2_subdev_state_get_compose(state, sel->pad);
 		return 0;
 	}
 
@@ -906,7 +995,7 @@  static int imx219_init_state(struct v4l2_subdev *sd,
 {
 	struct v4l2_subdev_format fmt = {
 		.which = V4L2_SUBDEV_FORMAT_TRY,
-		.pad = 0,
+		.pad = IMX219_PAD_SOURCE,
 		.format = {
 			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
 			.width = supported_modes[0].width,
@@ -1174,10 +1263,18 @@  static int imx219_probe(struct i2c_client *client)
 			    V4L2_SUBDEV_FL_HAS_EVENTS;
 	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
 
-	/* Initialize source pad */
-	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
+	/*
+	 * Initialize the pads. To preserve backward compatibility with
+	 * userspace that used the sensor before the introduction of the
+	 * internal image pad, the external source pad is numbered 0 and the
+	 * internal image pad numbered 1.
+	 */
+	imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
+	imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
+					     | MEDIA_PAD_FL_INTERNAL;
 
-	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
+	ret = media_entity_pads_init(&imx219->sd.entity,
+				     ARRAY_SIZE(imx219->pads), imx219->pads);
 	if (ret) {
 		dev_err(dev, "failed to init entity pads: %d\n", ret);
 		goto error_handler_free;