Re: [PATCH v2 02/10] media: Add Y012 video format

[Nicolas Dufresne]

Le mercredi 01 février 2023 à 14:02 +0800, Ming Qian a écrit :
> Y012 is a luma-only formats with 12-bits per pixel,
> expanded to 16bits.
> Data in the 12 high bits, zeros in the 4 low bits,
> arranged in little endian order.
> 
> Signed-off-by: Ming Qian <ming.qian@xxxxxxx>
> ---
>  .../userspace-api/media/v4l/pixfmt-yuv-luma.rst       | 11 +++++++++++
>  drivers/media/v4l2-core/v4l2-ioctl.c                  |  1 +
>  include/uapi/linux/videodev2.h                        |  1 +
>  3 files changed, 13 insertions(+)
> 
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
> index 6a387f9df3ba..3ffa29000238 100644
> --- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
> @@ -103,6 +103,17 @@ are often referred to as greyscale formats.
>        - ...
>        - ...
>  
> +    * .. _V4L2-PIX-FMT-Y012:

Why the 0, can't this be name Y12 (just like Y14) ?

> +
> +      - ``V4L2_PIX_FMT_Y012``
> +      - 'Y012'
> +
> +      - Y'\ :sub:`0`\ [3:0] `0000`
> +      - Y'\ :sub:`0`\ [11:4]
> +      - ...
> +      - ...
> +      - ...
> +
>      * .. _V4L2-PIX-FMT-Y14:
>  
>        - ``V4L2_PIX_FMT_Y14``
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 067dbdd0a9ef..0ee730aa6cc7 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1303,6 +1303,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
>  	case V4L2_PIX_FMT_Y6:		descr = "6-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y10:		descr = "10-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y12:		descr = "12-bit Greyscale"; break;
> +	case V4L2_PIX_FMT_Y012:		descr = "12-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y14:		descr = "14-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y16:		descr = "16-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y16_BE:	descr = "16-bit Greyscale BE"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 5448aa3b7858..3d8f89bff33c 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -583,6 +583,7 @@ struct v4l2_pix_format {
>  #define V4L2_PIX_FMT_Y6      v4l2_fourcc('Y', '0', '6', ' ') /*  6  Greyscale     */
>  #define V4L2_PIX_FMT_Y10     v4l2_fourcc('Y', '1', '0', ' ') /* 10  Greyscale     */
>  #define V4L2_PIX_FMT_Y12     v4l2_fourcc('Y', '1', '2', ' ') /* 12  Greyscale     */
> +#define V4L2_PIX_FMT_Y012    v4l2_fourcc('Y', '0', '1', '2') /* 12  Greyscale     */
>  #define V4L2_PIX_FMT_Y14     v4l2_fourcc('Y', '1', '4', ' ') /* 14  Greyscale     */
>  #define V4L2_PIX_FMT_Y16     v4l2_fourcc('Y', '1', '6', ' ') /* 16  Greyscale     */
>  #define V4L2_PIX_FMT_Y16_BE  v4l2_fourcc_be('Y', '1', '6', ' ') /* 16  Greyscale BE  */