Re: [PATCH v3 06/10] media: staging: rkisp1: add a helper function to enumerate supported mbus formats on capture

[Helen Koike <helen.koike@collabora.com>]

Hi Dafna,

Thanks for the patch.

On 7/23/20 10:20 AM, Dafna Hirschfeld wrote:
> Add a function 'rkisp1_cap_enum_mbus_codes' that receive
> a pointer to 'v4l2_subdev_mbus_code_enum' and returns the
> next supported mbus format of the capture. The function
> assumes that pixel formats with identical 'mbus' are grouped
> together in the hardcoded arrays, therefore the order of the
> entries in the array 'rkisp1_sp_fmts' are adjusted.
> This function is a helper for the media bus enumeration of
> the source pad of the resizer entity.
> 
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
> ---
>  drivers/staging/media/rkisp1/rkisp1-capture.c | 77 ++++++++++++-------
>  drivers/staging/media/rkisp1/rkisp1-common.h  |  8 ++
>  2 files changed, 58 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/staging/media/rkisp1/rkisp1-capture.c b/drivers/staging/media/rkisp1/rkisp1-capture.c
> index 5dd91b5f82a4..4dabd07a3da9 100644
> --- a/drivers/staging/media/rkisp1/rkisp1-capture.c
> +++ b/drivers/staging/media/rkisp1/rkisp1-capture.c
> @@ -112,6 +112,13 @@ static const struct rkisp1_capture_fmt_cfg rkisp1_mp_fmts[] = {

I would also add a comment in the beginning of this array saying that mbus
should be grouped together for the sake of enum.

>  		.write_format = RKISP1_MI_CTRL_MP_WRITE_YUV_PLA_OR_RAW8,
>  		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
>  	},
> +	/* yuv400 */
> +	{
> +		.fourcc = V4L2_PIX_FMT_GREY,
> +		.uv_swap = 0,
> +		.write_format = RKISP1_MI_CTRL_MP_WRITE_YUVINT,
> +		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> +	},
>  	/* yuv420 */
>  	{
>  		.fourcc = V4L2_PIX_FMT_NV21,
> @@ -144,13 +151,6 @@ static const struct rkisp1_capture_fmt_cfg rkisp1_mp_fmts[] = {
>  		.write_format = RKISP1_MI_CTRL_MP_WRITE_YUV_PLA_OR_RAW8,
>  		.mbus = MEDIA_BUS_FMT_YUYV8_1_5X8,
>  	},
> -	/* yuv400 */
> -	{
> -		.fourcc = V4L2_PIX_FMT_GREY,
> -		.uv_swap = 0,
> -		.write_format = RKISP1_MI_CTRL_MP_WRITE_YUVINT,
> -		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> -	},
>  	/* raw */
>  	{
>  		.fourcc = V4L2_PIX_FMT_SRGGB8,
> @@ -236,6 +236,26 @@ static const struct rkisp1_capture_fmt_cfg rkisp1_sp_fmts[] = {
>  		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_YUV422,
>  		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
>  	},
> +	/* yuv400 */
> +	{
> +		.fourcc = V4L2_PIX_FMT_GREY,
> +		.uv_swap = 0,
> +		.write_format = RKISP1_MI_CTRL_SP_WRITE_INT,
> +		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_YUV400,
> +		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> +	},
> +	/* rgb */
> +	{
> +		.fourcc = V4L2_PIX_FMT_XBGR32,
> +		.write_format = RKISP1_MI_CTRL_SP_WRITE_PLA,
> +		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_RGB888,
> +		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> +	}, {
> +		.fourcc = V4L2_PIX_FMT_RGB565,
> +		.write_format = RKISP1_MI_CTRL_SP_WRITE_PLA,
> +		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_RGB565,
> +		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> +	},
>  	/* yuv420 */
>  	{
>  		.fourcc = V4L2_PIX_FMT_NV21,
> @@ -274,26 +294,6 @@ static const struct rkisp1_capture_fmt_cfg rkisp1_sp_fmts[] = {
>  		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_YUV420,
>  		.mbus = MEDIA_BUS_FMT_YUYV8_1_5X8,
>  	},
> -	/* yuv400 */
> -	{
> -		.fourcc = V4L2_PIX_FMT_GREY,
> -		.uv_swap = 0,
> -		.write_format = RKISP1_MI_CTRL_SP_WRITE_INT,
> -		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_YUV400,
> -		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> -	},
> -	/* rgb */
> -	{
> -		.fourcc = V4L2_PIX_FMT_XBGR32,
> -		.write_format = RKISP1_MI_CTRL_SP_WRITE_PLA,
> -		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_RGB888,
> -		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> -	}, {
> -		.fourcc = V4L2_PIX_FMT_RGB565,
> -		.write_format = RKISP1_MI_CTRL_SP_WRITE_PLA,
> -		.output_format = RKISP1_MI_CTRL_SP_OUTPUT_RGB565,
> -		.mbus = MEDIA_BUS_FMT_YUYV8_2X8,
> -	},
>  };
>  
>  static const struct rkisp1_capture_config rkisp1_capture_config_mp = {
> @@ -334,6 +334,29 @@ rkisp1_vdev_to_node(struct video_device *vdev)
>  	return container_of(vdev, struct rkisp1_vdev_node, vdev);
>  }
>  
> +int rkisp1_cap_enum_mbus_codes(struct rkisp1_capture *cap,
> +			       struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	const struct rkisp1_capture_fmt_cfg *fmts = cap->config->fmts;
> +	u32 curr_mbus = fmts[0].mbus;

Maybe you could use code->code as the current, since in case of error
-EINVAL should be returned and this value should be ignored iirc.

> +	int i, n = 0;

unsigned

> +
> +	if (code->index == 0) {

if (!code->index)

> +		code->code = fmts[0].mbus;
> +		return 0;
> +	}
> +
> +	for (i = 1; i < cap->config->fmt_size; i++)
> +		if (fmts[i].mbus != curr_mbus) {

You can decrease one indentation level with:

		if (fmts[i].mbus == curr_mbus)
				continue;

Regards,
Helen

> +			curr_mbus = fmts[i].mbus;
> +			if (++n == code->index) {
> +				code->code = curr_mbus;
> +				return 0;
> +			}
> +		}
> +	return -EINVAL;
> +}
> +
>  /* ----------------------------------------------------------------------------
>   * Stream operations for self-picture path (sp) and main-picture path (mp)
>   */
> diff --git a/drivers/staging/media/rkisp1/rkisp1-common.h b/drivers/staging/media/rkisp1/rkisp1-common.h
> index 3dc51d703f73..73e1963cc47a 100644
> --- a/drivers/staging/media/rkisp1/rkisp1-common.h
> +++ b/drivers/staging/media/rkisp1/rkisp1-common.h
> @@ -297,6 +297,14 @@ static inline u32 rkisp1_read(struct rkisp1_device *rkisp1, unsigned int addr)
>  	return readl(rkisp1->base_addr + addr);
>  }
>  
> +/*
> + * rkisp1_cap_enum_mbus_codes - A helper function that return the i'th supported mbus code
> + *				of the capture entity. This is used to enumerate the supported
> + *				mbus codes on the source pad of the resizer.
> + */
> +int rkisp1_cap_enum_mbus_codes(struct rkisp1_capture *cap,
> +			       struct v4l2_subdev_mbus_code_enum *code);
> +
>  void rkisp1_sd_adjust_crop_rect(struct v4l2_rect *crop,
>  				const struct v4l2_rect *bounds);
>  
>