Re: [PATCH v7 05/15] media: i2c: imx219: Add embedded data support

[Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>]

On 28/03/2024 23:49, Laurent Pinchart wrote:
> Hi Tomi,
>
> On Wed, Mar 27, 2024 at 12:51:11PM +0200, Tomi Valkeinen wrote:
> > On 25/03/2024 00:08, Laurent Pinchart wrote:
> > > The IMX219 generates embedded data unconditionally. Report it as an
> > > additional stream, with a new internal embedded data pad, and update
> > > subdev operations accordingly.
> > >
> > > Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > > ---
> > > Changes since v6:
> > >
> > > - Get format from IMX219_STREAM_IMAGE in imx219_set_ctrl()
> > > - Fix mbus code for second stream in imx219_get_frame_desc()
> > > - Set V4L2_SUBDEV_ROUTE_FL_IMMUTABLE flag on route
> > > ---
> > >    drivers/media/i2c/imx219.c | 188 +++++++++++++++++++++++++++++++------
> > >    1 file changed, 160 insertions(+), 28 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > > index fa64bc402c9a..86a0ebf6d65f 100644
> > > --- a/drivers/media/i2c/imx219.c
> > > +++ b/drivers/media/i2c/imx219.c
> > > @@ -149,6 +149,9 @@
> > >    #define IMX219_PIXEL_ARRAY_WIDTH	3280U
> > >    #define IMX219_PIXEL_ARRAY_HEIGHT	2464U
> > >    
> > > +/* Embedded metadata stream height */
> > > +#define IMX219_EMBEDDED_DATA_HEIGHT	2U
> > > +
> > >    /* Mode : resolution and related config&values */
> > >    struct imx219_mode {
> > >    	/* Frame width */
> > > @@ -317,9 +320,15 @@ static const struct imx219_mode supported_modes[] = {
> > >    enum imx219_pad_ids {
> > >    	IMX219_PAD_SOURCE,
> > >    	IMX219_PAD_IMAGE,
> > > +	IMX219_PAD_EDATA,
> > >    	IMX219_NUM_PADS,
> > >    };
> > >    
> > > +enum imx219_stream_ids {
> > > +	IMX219_STREAM_IMAGE,
> > > +	IMX219_STREAM_EDATA,
> > > +};
> > > +
> > >    struct imx219 {
> > >    	struct v4l2_subdev sd;
> > >    	struct media_pad pads[IMX219_NUM_PADS];
> > > @@ -382,7 +391,8 @@ 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, IMX219_PAD_SOURCE);
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +					      IMX219_STREAM_IMAGE);
> >
> > As mentioned in the previous mail, all these lines could be in a
> > separate patch, they are not related to embedded data support.
>
> Done.
>
> > >    	if (ctrl->id == V4L2_CID_VBLANK) {
> > >    		int exposure_max, exposure_def;
> > > @@ -610,6 +620,25 @@ static unsigned int imx219_format_bpp(u32 code)
> > >    	}
> > >    }
> > >    
> > > +/* Return the embedded data format corresponding to an image format. */
> > > +static u32 imx219_format_edata(u32 code)
> > > +{
> > > +	switch (code) {
> > > +	case MEDIA_BUS_FMT_SRGGB8_1X8:
> > > +	case MEDIA_BUS_FMT_SGRBG8_1X8:
> > > +	case MEDIA_BUS_FMT_SGBRG8_1X8:
> > > +	case MEDIA_BUS_FMT_SBGGR8_1X8:
> > > +		return MEDIA_BUS_FMT_META_8;
> > > +
> > > +	case MEDIA_BUS_FMT_SRGGB10_1X10:
> > > +	case MEDIA_BUS_FMT_SGRBG10_1X10:
> > > +	case MEDIA_BUS_FMT_SGBRG10_1X10:
> > > +	case MEDIA_BUS_FMT_SBGGR10_1X10:
> > > +	default:
> > > +		return MEDIA_BUS_FMT_META_10;
> > > +	}
> > > +}
> >
> > You could also switch based on imx219_format_bpp().
>
> Is that better ? I can also get rid of the function and do this in its
> single caller:
>
>          ed_format->code = imx219_format_bpp(format->code) == 10
>                          ? MEDIA_BUS_FMT_META_10 : MEDIA_BUS_FMT_META_8;
>
> but a helper function probably makes things a bit more readable. Let me
> know what you prefer.

Helper is good. My thinking was that as we pick the META format based 
not on the pixel format as such, but on the bpp, using 
imx219_format_bpp() would be clearer. Up to you.

> > >    static int imx219_set_framefmt(struct imx219 *imx219,
> > >    			       struct v4l2_subdev_state *state)
> > >    {
> > > @@ -619,7 +648,8 @@ static int imx219_set_framefmt(struct imx219 *imx219,
> > >    	u64 bin_h, bin_v;
> > >    	int ret = 0;
> > >    
> > > -	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +					      IMX219_STREAM_IMAGE);
> > >    	crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > >    	bpp = imx219_format_bpp(format->code);
> > >    
> > > @@ -774,17 +804,33 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
> > >    {
> > >    	struct imx219 *imx219 = to_imx219(sd);
> > >    
> > > -	if (code->pad == IMX219_PAD_IMAGE) {
> > > +	switch (code->pad) {
> > > +	case IMX219_PAD_IMAGE:
> > >    		/* The internal image pad is hardwired to the native format. */
> > > -		if (code->index)
> > > +		if (code->index > 0)
> >
> > Was there something wrong with if (code->index)? I don't mind the
> > change, but it's not related to adding embedded data support.
>
> I find it more explicit, I read it as "if the code index is higher than
> the number of supported values" instead of "if the code has an index".
>
> > Also, you added the line in patch 2, so you could change it already in
> > there.
>
> I'll change it there.
>
> > Normally it wouldn't matter that much, but I think it makes sense trying
> > to make the imx219 patches as clean as possible, as they'll be used for
> > reference.
>
> Yes, I noticed an unusual amount of nit-picking :-)

Thank you!

> > >    			return -EINVAL;
> > >    
> > >    		code->code = IMX219_NATIVE_FORMAT;
> > > -	} else {
> > > -		/*
> > > -		 * On the source pad, the sensor supports multiple raw formats
> > > -		 * with different bit depths.
> > > -		 */
> > > +		return 0;
> > > +
> > > +	case IMX219_PAD_EDATA:
> > > +		if (code->index > 0)
> > > +			return -EINVAL;
> > > +
> > > +		code->code = MEDIA_BUS_FMT_CCS_EMBEDDED;
> > > +		return 0;
> > > +
> > > +	case IMX219_PAD_SOURCE:
> > > +	default:
> > > +		break;
> > > +	}
> > > +
> > > +	/*
> > > +	 * On the source pad, the sensor supports multiple image raw formats
> > > +	 * with different bit depths. The embedded data format bit depth
> > > +	 * follows the image stream.
> > > +	 */
> > > +	if (code->stream == IMX219_STREAM_IMAGE) {
> > >    		u32 format;
> >
> > It seems we get these constructs quite often:
> >
> > 	switch (pad) {
> > 	case IMX219_PAD_IMAGE:
> > 		return;
> > 	case IMX219_PAD_EDATA:
> > 		return;
> > 	case IMX219_PAD_SOURCE:
> > 	default:
> > 		break;
> > 	}
> >
> > 	if (stream == IMX219_STREAM_IMAGE) {
> > 	} else {
> > 	}
> >
> > I wonder would it be better to make a macro that combines the pad and
> > stream numbers, and then one could do:
> >
> > 	switch (padstream) {
> > 		case IMX219_PADSTREAM_IMAGE:
> > 		case IMX219_PADSTREAM_EDATA:
> > 		case IMX219_PADSTREAM_SOURCE_IMAGE:
> > 		case IMX219_PADSTREAM_SOURCE_EDATA:
> > 	}
>
> I could also write
>
> 	if (code->pad == IMX219_PAD_IMAGE) {
> 		...
> 	} else if (code->pad == IMX219_PAD_EDATA) {
> 		...
> 	} else if (code->stream == IMX219_STREAM_IMAGE) {
> 		...
> 	} else {
> 		...
> 	}
>
> I'm not entirely sure it would be significantly more readable. I don't
> mind changing the code if anyone has a clear preference, but I'd like to
> avoid going back and forth. Maybe Sakari and you can decide ?

I don't have any clear preference. None of the options look 
significantly better than the others, and none look perfect =).

 Tomi

> > >    
> > >    		if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > @@ -792,6 +838,15 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
> > >    
> > >    		format = imx219_mbus_formats[code->index * 4];
> > >    		code->code = imx219_get_format_code(imx219, format);
> > > +	} else {
> > > +		struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +		if (code->index > 0)
> > > +			return -EINVAL;
> > > +
> > > +		fmt = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +						   IMX219_STREAM_EDATA);
> > > +		code->code = fmt->code;
> > >    	}
> > >    
> > >    	return 0;
> > > @@ -803,7 +858,8 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > >    {
> > >    	struct imx219 *imx219 = to_imx219(sd);
> > >    
> > > -	if (fse->pad == IMX219_PAD_IMAGE) {
> > > +	switch (fse->pad) {
> > > +	case IMX219_PAD_IMAGE:
> > >    		if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
> > >    			return -EINVAL;
> > >    
> > > @@ -811,7 +867,24 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > >    		fse->max_width = IMX219_NATIVE_WIDTH;
> > >    		fse->min_height = IMX219_NATIVE_HEIGHT;
> > >    		fse->max_height = IMX219_NATIVE_HEIGHT;
> > > -	} else {
> > > +		return 0;
> > > +
> > > +	case IMX219_PAD_EDATA:
> > > +		if (fse->code != MEDIA_BUS_FMT_CCS_EMBEDDED || fse->index > 0)
> > > +			return -EINVAL;
> > > +
> > > +		fse->min_width = IMX219_NATIVE_WIDTH;
> > > +		fse->max_width = IMX219_NATIVE_WIDTH;
> > > +		fse->min_height = IMX219_EMBEDDED_DATA_HEIGHT;
> > > +		fse->max_height = IMX219_EMBEDDED_DATA_HEIGHT;
> > > +		return 0;
> > > +
> > > +	case IMX219_PAD_SOURCE:
> > > +	default:
> > > +		break;
> > > +	}
> > > +
> > > +	if (fse->stream == IMX219_STREAM_IMAGE) {
> > >    		if (fse->code != imx219_get_format_code(imx219, fse->code) ||
> > >    		    fse->index >= ARRAY_SIZE(supported_modes))
> > >    			return -EINVAL;
> > > @@ -820,6 +893,21 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > >    		fse->max_width = fse->min_width;
> > >    		fse->min_height = supported_modes[fse->index].height;
> > >    		fse->max_height = fse->min_height;
> > > +	} else {
> > > +		struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +		fmt = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +						   IMX219_STREAM_EDATA);
> > > +		if (fse->code != fmt->code)
> > > +			return -EINVAL;
> > > +
> > > +		if (fse->index)
> > > +			return -EINVAL;
> > > +
> > > +		fse->min_width = fmt->width;
> > > +		fse->max_width = fmt->width;
> > > +		fse->min_height = IMX219_EMBEDDED_DATA_HEIGHT;
> > > +		fse->max_height = IMX219_EMBEDDED_DATA_HEIGHT;
> > >    	}
> > >    
> > >    	return 0;
> > > @@ -831,6 +919,7 @@ 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 *ed_format;
> > >    	struct v4l2_mbus_framefmt *format;
> > >    	struct v4l2_rect *compose;
> > >    	struct v4l2_rect *crop;
> > > @@ -838,9 +927,9 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > >    
> > >    	/*
> > >    	 * The driver is mode-based, the format can be set on the source pad
> > > -	 * only.
> > > +	 * only, and only for the image streeam.
> > >    	 */
> > > -	if (fmt->pad != IMX219_PAD_SOURCE)
> > > +	if (fmt->pad != IMX219_PAD_SOURCE || fmt->stream != IMX219_STREAM_IMAGE)
> > >    		return v4l2_subdev_get_fmt(sd, state, fmt);
> > >    
> > >    	/*
> > > @@ -897,15 +986,31 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > >    	 * 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 = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE,
> > > +					  IMX219_STREAM_IMAGE);
> > >    	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 = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +					      IMX219_STREAM_IMAGE);
> > >    	*format = fmt->format;
> > >    
> > > +	/*
> > > +	 * Finally, update the formats on the sink and source sides of the
> > > +	 * embedded data stream.
> > > +	 */
> > > +	ed_format = v4l2_subdev_state_get_format(state, IMX219_PAD_EDATA);
> > > +	ed_format->code = imx219_format_edata(format->code);
> > > +	ed_format->width = format->width;
> > > +	ed_format->height = IMX219_EMBEDDED_DATA_HEIGHT;
> > > +	ed_format->field = V4L2_FIELD_NONE;
> > > +
> > > +	format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +					      IMX219_STREAM_EDATA);
> > > +	*format = *ed_format;
> > > +
> > >    	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> > >    		int exposure_max;
> > >    		int exposure_def;
> > > @@ -944,6 +1049,13 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > >    {
> > >    	struct v4l2_rect *compose;
> > >    
> > > +	/*
> > > +	 * The embedded data stream doesn't support selection rectangles,
> > > +	 * neither on the embedded data pad nor on the source pad.
> > > +	 */
> > > +	if (sel->pad == IMX219_PAD_EDATA || sel->stream != 0)
> > > +		return -EINVAL;
> > > +
> > >    	switch (sel->target) {
> > >    	case V4L2_SEL_TGT_NATIVE_SIZE:
> > >    		if (sel->pad != IMX219_PAD_IMAGE)
> > > @@ -996,12 +1108,19 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > >    static int imx219_init_state(struct v4l2_subdev *sd,
> > >    			     struct v4l2_subdev_state *state)
> > >    {
> > > -	struct v4l2_subdev_route routes[1] = {
> > > +	struct v4l2_subdev_route routes[2] = {
> > >    		{
> > >    			.sink_pad = IMX219_PAD_IMAGE,
> > >    			.sink_stream = 0,
> > >    			.source_pad = IMX219_PAD_SOURCE,
> > > -			.source_stream = 0,
> > > +			.source_stream = IMX219_STREAM_IMAGE,
> > > +			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE |
> > > +				 V4L2_SUBDEV_ROUTE_FL_IMMUTABLE,
> > > +		}, {
> > > +			.sink_pad = IMX219_PAD_EDATA,
> > > +			.sink_stream = 0,
> > > +			.source_pad = IMX219_PAD_SOURCE,
> > > +			.source_stream = IMX219_STREAM_EDATA,
> > >    			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE |
> > >    				 V4L2_SUBDEV_ROUTE_FL_IMMUTABLE,
> > >    		},
> > > @@ -1014,7 +1133,7 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> > >    	struct v4l2_subdev_format fmt = {
> > >    		.which = V4L2_SUBDEV_FORMAT_TRY,
> > >    		.pad = IMX219_PAD_SOURCE,
> > > -		.stream = 0,
> > > +		.stream = IMX219_STREAM_IMAGE,
> > >    		.format = {
> > >    			.code = MEDIA_BUS_FMT_SRGGB10_1X10,
> > >    			.width = supported_modes[0].width,
> > > @@ -1027,6 +1146,10 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> > >    	if (ret)
> > >    		return ret;
> > >    
> > > +	/*
> > > +	 * Set the image stream format on the source pad. This will be
> > > +	 * propagated to all formats and selection rectangles internally.
> > > +	 */
> > >    	imx219_set_pad_format(sd, state, &fmt);
> > >    
> > >    	return 0;
> > > @@ -1035,29 +1158,36 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> > >    static int imx219_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad,
> > >    				 struct v4l2_mbus_frame_desc *fd)
> > >    {
> > > -	const struct v4l2_mbus_framefmt *fmt;
> > >    	struct v4l2_subdev_state *state;
> > > -	u32 code;
> > > +	u32 img_code;
> > > +	u32 ed_code;
> > >    
> > >    	if (pad != IMX219_PAD_SOURCE)
> > >    		return -EINVAL;
> > >    
> > >    	state = v4l2_subdev_lock_and_get_active_state(sd);
> > > -	fmt = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE, 0);
> > > -	code = fmt->code;
> > > +	img_code = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +						IMX219_STREAM_IMAGE)->code;
> > > +	ed_code = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE,
> > > +					       IMX219_STREAM_EDATA)->code;
> > >    	v4l2_subdev_unlock_state(state);
> > >    
> > >    	fd->type = V4L2_MBUS_FRAME_DESC_TYPE_CSI2;
> > > -	fd->num_entries = 1;
> > > +	fd->num_entries = 2;
> > >    
> > >    	memset(fd->entry, 0, sizeof(fd->entry));
> > >    
> > > -	fd->entry[0].pixelcode = code;
> > > -	fd->entry[0].stream = 0;
> > > +	fd->entry[0].pixelcode = img_code;
> > > +	fd->entry[0].stream = IMX219_STREAM_IMAGE;
> > >    	fd->entry[0].bus.csi2.vc = 0;
> > > -	fd->entry[0].bus.csi2.dt = imx219_format_bpp(code) == 8
> > > +	fd->entry[0].bus.csi2.dt = imx219_format_bpp(img_code) == 8
> > >    				 ? MIPI_CSI2_DT_RAW8 : MIPI_CSI2_DT_RAW10;
> > >    
> > > +	fd->entry[1].pixelcode = ed_code;
> > > +	fd->entry[1].stream = IMX219_STREAM_EDATA;
> > > +	fd->entry[1].bus.csi2.vc = 0;
> > > +	fd->entry[1].bus.csi2.dt = MIPI_CSI2_DT_EMBEDDED_8B;
> > > +
> > >    	return 0;
> > >    }
> > >    
> > > @@ -1321,12 +1451,14 @@ static int imx219_probe(struct i2c_client *client)
> > >    	/*
> > >    	 * 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.
> > > +	 * internal pads, the external source pad is numbered 0 and the internal
> > > +	 * image and embedded data pads numbered 1 and 2 respectively.
> > >    	 */
> > >    	imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> > >    	imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
> > >    					     | MEDIA_PAD_FL_INTERNAL;
> > > +	imx219->pads[IMX219_PAD_EDATA].flags = MEDIA_PAD_FL_SINK
> > > +					     | MEDIA_PAD_FL_INTERNAL;
> > >    
> > >    	ret = media_entity_pads_init(&imx219->sd.entity,
> > >    				     ARRAY_SIZE(imx219->pads), imx219->pads);