Re: [PATCH v5 04/14] staging: media: starfive: Add a params sink pad and a scd source pad for ISP

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hello Changhuang,

Thank you for the patch.

On Tue, Jul 09, 2024 at 01:38:14AM -0700, Changhuang Liang wrote:
> StarFive ISP can use params sink pad to transmit ISP parameters and use
> scd source pad to capture statistics collection data.
> 
> Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
> ---
>  .../staging/media/starfive/camss/stf-isp.c    | 77 +++++++++++++++++--
>  .../staging/media/starfive/camss/stf-isp.h    |  2 +
>  2 files changed, 71 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/staging/media/starfive/camss/stf-isp.c b/drivers/staging/media/starfive/camss/stf-isp.c
> index 4e6e26736852..0ebffd09842a 100644
> --- a/drivers/staging/media/starfive/camss/stf-isp.c
> +++ b/drivers/staging/media/starfive/camss/stf-isp.c
> @@ -21,13 +21,23 @@ static const struct stf_isp_format isp_formats_sink[] = {
>  	{ MEDIA_BUS_FMT_SBGGR10_1X10, 10 },
>  };
>  
> +static const struct stf_isp_format isp_formats_sink_params[] = {
> +	{ MEDIA_BUS_FMT_METADATA_FIXED },
> +};
> +
>  static const struct stf_isp_format isp_formats_source[] = {
>  	{ MEDIA_BUS_FMT_YUYV8_1_5X8, 8 },
>  };
>  
> +static const struct stf_isp_format isp_formats_source_scd[] = {
> +	{ MEDIA_BUS_FMT_METADATA_FIXED },
> +};
> +
>  static const struct stf_isp_format_table isp_formats_st7110[] = {
>  	{ isp_formats_sink, ARRAY_SIZE(isp_formats_sink) },
> +	{ isp_formats_sink_params, ARRAY_SIZE(isp_formats_sink_params) },
>  	{ isp_formats_source, ARRAY_SIZE(isp_formats_source) },
> +	{ isp_formats_source_scd, ARRAY_SIZE(isp_formats_source_scd) },
>  };
>  
>  static const struct stf_isp_format *
> @@ -93,13 +103,19 @@ static void isp_try_format(struct stf_isp_dev *isp_dev,
>  
>  	formats = &isp_dev->formats[pad];
>  
> -	fmt->width = clamp_t(u32, fmt->width, STFCAMSS_FRAME_MIN_WIDTH,
> -			     STFCAMSS_FRAME_MAX_WIDTH);
> -	fmt->height = clamp_t(u32, fmt->height, STFCAMSS_FRAME_MIN_HEIGHT,
> -			      STFCAMSS_FRAME_MAX_HEIGHT);
> -	fmt->height &= ~0x1;
> +	if (pad != STF_ISP_PAD_SRC_SCD && pad != STF_ISP_PAD_SINK_PARAMS) {
> +		fmt->width = clamp_t(u32, fmt->width, STFCAMSS_FRAME_MIN_WIDTH,
> +				     STFCAMSS_FRAME_MAX_WIDTH);
> +		fmt->height = clamp_t(u32, fmt->height, STFCAMSS_FRAME_MIN_HEIGHT,
> +				      STFCAMSS_FRAME_MAX_HEIGHT);
> +		fmt->height &= ~0x1;
> +		fmt->colorspace = V4L2_COLORSPACE_SRGB;
> +	} else {
> +		fmt->width = 1;
> +		fmt->height = 1;

You should set fmt->colorspace here too. I think you can set it to 0.

> +	}
> +
>  	fmt->field = V4L2_FIELD_NONE;
> -	fmt->colorspace = V4L2_COLORSPACE_SRGB;
>  	fmt->flags = 0;
>  
>  	if (!stf_g_fmt_by_mcode(formats, fmt->code))
> @@ -119,7 +135,7 @@ static int isp_enum_mbus_code(struct v4l2_subdev *sd,
>  
>  		formats = &isp_dev->formats[code->pad];
>  		code->code = formats->fmts[code->index].code;
> -	} else {
> +	} else if (code->pad == STF_ISP_PAD_SRC) {
>  		struct v4l2_mbus_framefmt *sink_fmt;
>  
>  		if (code->index >= ARRAY_SIZE(isp_formats_source))
> @@ -131,6 +147,10 @@ static int isp_enum_mbus_code(struct v4l2_subdev *sd,
>  		code->code = sink_fmt->code;
>  		if (!code->code)
>  			return -EINVAL;
> +	} else {
> +		if (code->index > 0)
> +			return -EINVAL;
> +		code->code = MEDIA_BUS_FMT_METADATA_FIXED;
>  	}
>  	code->flags = 0;
>  
> @@ -151,6 +171,9 @@ static int isp_set_format(struct v4l2_subdev *sd,
>  	isp_try_format(isp_dev, state, fmt->pad, &fmt->format);
>  	*format = fmt->format;
>  
> +	if (fmt->pad == STF_ISP_PAD_SRC_SCD || fmt->pad == STF_ISP_PAD_SINK_PARAMS)
> +		return 0;
> +
>  	isp_dev->current_fmt = stf_g_fmt_by_mcode(&isp_dev->formats[fmt->pad],
>  						  fmt->format.code);
>  
> @@ -202,6 +225,9 @@ static int isp_get_selection(struct v4l2_subdev *sd,
>  	struct v4l2_subdev_format fmt = { 0 };
>  	struct v4l2_rect *rect;
>  
> +	if (sel->pad == STF_ISP_PAD_SRC_SCD || sel->pad == STF_ISP_PAD_SINK_PARAMS)
> +		return -EINVAL;
> +
>  	switch (sel->target) {
>  	case V4L2_SEL_TGT_CROP_BOUNDS:
>  		if (sel->pad == STF_ISP_PAD_SINK) {
> @@ -239,6 +265,9 @@ static int isp_set_selection(struct v4l2_subdev *sd,
>  	struct stf_isp_dev *isp_dev = v4l2_get_subdevdata(sd);
>  	struct v4l2_rect *rect;
>  
> +	if (sel->pad == STF_ISP_PAD_SRC_SCD || sel->pad == STF_ISP_PAD_SINK_PARAMS)
> +		return -EINVAL;
> +
>  	if (sel->target != V4L2_SEL_TGT_CROP)
>  		return -EINVAL;
>  
> @@ -296,8 +325,38 @@ static int isp_init_formats(struct v4l2_subdev *sd,

While at it, you could rename the function to isp_init_state().

>  			.height = 1080
>  		}
>  	};
> +	struct v4l2_subdev_format format_params = {
> +		.pad = STF_ISP_PAD_SINK_PARAMS,
> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,

That's not quite right, as the .init_state() handler is used to
initialized both the TRY and ACTIVE states. As the "which" field is
currently ignored through the driver the code should behave correctly
(as far as I can tell), but you may want at some point to initialize the
formats and selection rectangles directly in this function instead of
calling isp_set_format().

> +		.format = {
> +			.code = MEDIA_BUS_FMT_METADATA_FIXED,
> +			.width = 1,
> +			.height = 1

According to
https://docs.kernel.org/userspace-api/media/v4l/subdev-formats.html#metadata-formats,
width and height should be set to 0 for MEDIA_BUS_FMT_METADATA_FIXED.

> +		}
> +	};
> +	struct v4l2_subdev_format format_scd = {
> +		.pad = STF_ISP_PAD_SRC_SCD,
> +		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
> +		.format = {
> +			.code = MEDIA_BUS_FMT_METADATA_FIXED,
> +			.width = 1,
> +			.height = 1
> +		}
> +	};
> +	int ret;
> +
> +	/* Init for STF_ISP_PAD_SINK and STF_ISP_PAD_SRC pad */
> +	ret = isp_set_format(sd, sd_state, &format);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Init for STF_ISP_PAD_SINK_PARAMS pad */
> +	ret = isp_set_format(sd, sd_state, &format_params);
> +	if (ret < 0)
> +		return ret;
>  
> -	return isp_set_format(sd, sd_state, &format);
> +	/* Init for STF_ISP_PAD_SRC_SCD pad */
> +	return isp_set_format(sd, sd_state, &format_scd);
>  }
>  
>  static const struct v4l2_subdev_video_ops isp_video_ops = {
> @@ -338,7 +397,9 @@ int stf_isp_register(struct stf_isp_dev *isp_dev, struct v4l2_device *v4l2_dev)
>  	v4l2_set_subdevdata(sd, isp_dev);
>  
>  	pads[STF_ISP_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> +	pads[STF_ISP_PAD_SINK_PARAMS].flags = MEDIA_PAD_FL_SINK;
>  	pads[STF_ISP_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
> +	pads[STF_ISP_PAD_SRC_SCD].flags = MEDIA_PAD_FL_SOURCE;
>  
>  	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_ISP;
>  	sd->entity.ops = &isp_media_ops;
> diff --git a/drivers/staging/media/starfive/camss/stf-isp.h b/drivers/staging/media/starfive/camss/stf-isp.h
> index 955cbb048363..bc7e7b0736fa 100644
> --- a/drivers/staging/media/starfive/camss/stf-isp.h
> +++ b/drivers/staging/media/starfive/camss/stf-isp.h
> @@ -392,7 +392,9 @@
>  /* pad id for media framework */
>  enum stf_isp_pad_id {
>  	STF_ISP_PAD_SINK = 0,
> +	STF_ISP_PAD_SINK_PARAMS,
>  	STF_ISP_PAD_SRC,
> +	STF_ISP_PAD_SRC_SCD,
>  	STF_ISP_PAD_MAX
>  };
>  

-- 
Regards,

Laurent Pinchart