Hi Laurent

On Thu, Mar 28, 2019 at 09:07:17AM +0200, Laurent Pinchart wrote:
> The V4L2 API is missing the 16-bit RGB555 formats for the RGBA, RGBX,
> ABGR, XBGR, BGRA and BGRX component orders. Add them, using the same
> 4CCs as DRM.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> ---
>  .../media/uapi/v4l/pixfmt-packed-rgb.rst      | 138 ++++++++++++++++++
>  include/uapi/linux/videodev2.h                |   6 +
>  2 files changed, 144 insertions(+)
>
> diff --git a/Documentation/media/uapi/v4l/pixfmt-packed-rgb.rst b/Documentation/media/uapi/v4l/pixfmt-packed-rgb.rst
> index b475cbba492f..9a9c1993b0fd 100644
> --- a/Documentation/media/uapi/v4l/pixfmt-packed-rgb.rst
> +++ b/Documentation/media/uapi/v4l/pixfmt-packed-rgb.rst
> @@ -323,6 +323,144 @@ next to each other in memory.
>        - g\ :sub:`4`
>        - g\ :sub:`3`
>        -
> +    * .. _V4L2-PIX-FMT-RGBA555:
> +
> +      - ``V4L2_PIX_FMT_RGBA555``
> +      - 'RA15'
> +
> +      - g\ :sub:`1`
> +      - g\ :sub:`0`
> +      - b\ :sub:`4`
> +      - b\ :sub:`3`
> +      - b\ :sub:`2`
> +      - b\ :sub:`1`
> +      - b\ :sub:`0`
> +      - a
> +
> +      - r\ :sub:`4`
> +      - r\ :sub:`3`
> +      - r\ :sub:`2`
> +      - r\ :sub:`1`
> +      - r\ :sub:`0`
> +      - g\ :sub:`4`
> +      - g\ :sub:`3`
> +      - g\ :sub:`2`
> +      -
> +    * .. _V4L2-PIX-FMT-RGBX555:
> +
> +      - ``V4L2_PIX_FMT_RGBX555``
> +      - 'RX15'
> +
> +      - g\ :sub:`1`
> +      - g\ :sub:`0`
> +      - b\ :sub:`4`
> +      - b\ :sub:`3`
> +      - b\ :sub:`2`
> +      - b\ :sub:`1`
> +      - b\ :sub:`0`
> +      -
> +
> +      - r\ :sub:`4`
> +      - r\ :sub:`3`
> +      - r\ :sub:`2`
> +      - r\ :sub:`1`
> +      - r\ :sub:`0`
> +      - g\ :sub:`4`
> +      - g\ :sub:`3`
> +      - g\ :sub:`2`
> +      -
> +    * .. _V4L2-PIX-FMT-ABGR555:
> +
> +      - ``V4L2_PIX_FMT_ABGR555``
> +      - 'AB15'
> +
> +      - g\ :sub:`2`
> +      - g\ :sub:`1`
> +      - g\ :sub:`0`
> +      - r\ :sub:`4`
> +      - r\ :sub:`3`
> +      - r\ :sub:`2`
> +      - r\ :sub:`1`
> +      - r\ :sub:`0`
> +
> +      - a
> +      - b\ :sub:`4`
> +      - b\ :sub:`3`
> +      - b\ :sub:`2`
> +      - b\ :sub:`1`
> +      - b\ :sub:`0`
> +      - g\ :sub:`4`
> +      - g\ :sub:`3`
> +      -
> +    * .. _V4L2-PIX-FMT-XBGR555:
> +
> +      - ``V4L2_PIX_FMT_XBGR555``
> +      - 'XB15'
> +
> +      - g\ :sub:`2`
> +      - g\ :sub:`1`
> +      - g\ :sub:`0`
> +      - r\ :sub:`4`
> +      - r\ :sub:`3`
> +      - r\ :sub:`2`
> +      - r\ :sub:`1`
> +      - r\ :sub:`0`
> +
> +      -
> +      - b\ :sub:`4`
> +      - b\ :sub:`3`
> +      - b\ :sub:`2`
> +      - b\ :sub:`1`
> +      - b\ :sub:`0`
> +      - g\ :sub:`4`
> +      - g\ :sub:`3`
> +      -
> +    * .. _V4L2-PIX-FMT-BGRA555:
> +
> +      - ``V4L2_PIX_FMT_BGRA555``
> +      - 'BA15'
> +
> +      - g\ :sub:`2`
> +      - g\ :sub:`1`
> +      - g\ :sub:`0`
> +      - r\ :sub:`4`
> +      - r\ :sub:`3`
> +      - r\ :sub:`2`
> +      - r\ :sub:`1`
> +      - r\ :sub:`0`
> +      - a
> +
> +      - b\ :sub:`4`
> +      - b\ :sub:`3`
> +      - b\ :sub:`2`
> +      - b\ :sub:`1`
> +      - b\ :sub:`0`
> +      - g\ :sub:`4`
> +      - g\ :sub:`3`
> +      -
> +    * .. _V4L2-PIX-FMT-BGRX555:
> +
> +      - ``V4L2_PIX_FMT_BGRX555``
> +      - 'BX15'
> +
> +      - g\ :sub:`2`
> +      - g\ :sub:`1`
> +      - g\ :sub:`0`
> +      - r\ :sub:`4`
> +      - r\ :sub:`3`
> +      - r\ :sub:`2`
> +      - r\ :sub:`1`
> +      - r\ :sub:`0`
> +      -
> +
> +      - b\ :sub:`4`
> +      - b\ :sub:`3`
> +      - b\ :sub:`2`
> +      - b\ :sub:`1`
> +      - b\ :sub:`0`
> +      - g\ :sub:`4`
> +      - g\ :sub:`3`
> +      -

I see the last 4 formats are identical in their components
disposition. Is this intended?

                   B1                          B0
          b7                   b0   b7                  b0
ABGR555 | g2 g1 g0 b4 b3 b2 b1 b0 | a r4 r3 r2 r1 r0 g4 g3 |
XBGR555 | g2 g1 g0 b4 b3 b2 b1 b0 | x r4 r3 r2 r1 r0 g4 g3 |
BGRA555 | g2 g1 g0 b4 b3 b2 b1 b0 | a r4 r3 r2 r1 r0 g4 g3 |
BGRX555 | g2 g1 g0 b4 b3 b2 b1 b0 | x r4 r3 r2 r1 r0 g4 g3 |

If there is any correlation with the naming scheme (but I think
there's not, at least not a strict one) 'a' and 'x' of BGR* formats
should be in the most significant bit of Byte 1.

Thanks
  j

>      * .. _V4L2-PIX-FMT-RGB565:
>
>        - ``V4L2_PIX_FMT_RGB565``
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index df9fa78a6ab7..fb6f01a7c91c 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -523,6 +523,12 @@ struct v4l2_pix_format {
>  #define V4L2_PIX_FMT_RGB555  v4l2_fourcc('R', 'G', 'B', 'O') /* 16  RGB-5-5-5     */
>  #define V4L2_PIX_FMT_ARGB555 v4l2_fourcc('A', 'R', '1', '5') /* 16  ARGB-1-5-5-5  */
>  #define V4L2_PIX_FMT_XRGB555 v4l2_fourcc('X', 'R', '1', '5') /* 16  XRGB-1-5-5-5  */
> +#define V4L2_PIX_FMT_RGBA555 v4l2_fourcc('R', 'A', '1', '5') /* 16  RGBA-5-5-5-1  */
> +#define V4L2_PIX_FMT_RGBX555 v4l2_fourcc('R', 'X', '1', '5') /* 16  RGBX-5-5-5-1  */
> +#define V4L2_PIX_FMT_ABGR555 v4l2_fourcc('A', 'B', '1', '5') /* 16  ABGR-1-5-5-5  */
> +#define V4L2_PIX_FMT_XBGR555 v4l2_fourcc('X', 'B', '1', '5') /* 16  XBGR-1-5-5-5  */
> +#define V4L2_PIX_FMT_BGRA555 v4l2_fourcc('B', 'A', '1', '5') /* 16  BGRA-5-5-5-1  */
> +#define V4L2_PIX_FMT_BGRX555 v4l2_fourcc('B', 'X', '1', '5') /* 16  BGRX-5-5-5-1  */
>  #define V4L2_PIX_FMT_RGB565  v4l2_fourcc('R', 'G', 'B', 'P') /* 16  RGB-5-6-5     */
>  #define V4L2_PIX_FMT_RGB555X v4l2_fourcc('R', 'G', 'B', 'Q') /* 16  RGB-5-5-5 BE  */
>  #define V4L2_PIX_FMT_ARGB555X v4l2_fourcc_be('A', 'R', '1', '5') /* 16  ARGB-5-5-5 BE */
> --
> Regards,
>
> Laurent Pinchart
>