Re: [PATCH v6 07/11] media: cedrus: Specify H264 startcode and decoding mode

From: Hans Verkuil
Date: Fri Aug 16 2019 - 03:38:28 EST


On 8/14/19 9:59 PM, Ezequiel Garcia wrote:
> The cedrus VPU is slice-based and expects V4L2_PIX_FMT_H264_SLICE
> buffers to contain H264 slices with no start code.
>
> Expose this to userspace with the newly added menu control.
>
> These two controls are specified as mandatory for applications,
> but we mark them as non-required on the driver side for
> backwards compatibility.
>
> Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> ---
> Changes in v6:
> * Adjust to control renames.
> Changes in v5:
> * Clarify commit log.
> Changes in v4:
> * New patch.
> ---
> drivers/staging/media/sunxi/cedrus/cedrus.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c b/drivers/staging/media/sunxi/cedrus/cedrus.c
> index 7bdc413bf727..69a836aa11ef 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
> @@ -77,6 +77,26 @@ static const struct cedrus_control cedrus_controls[] = {
> .codec = CEDRUS_CODEC_H264,
> .required = true,
> },
> + {
> + .cfg = {
> + .id = V4L2_CID_MPEG_VIDEO_H264_DECODE_MODE,
> + .max = V4L2_MPEG_VIDEO_H264_DECODE_MODE_SLICE_BASED,
> + .def = V4L2_MPEG_VIDEO_H264_DECODE_MODE_SLICE_BASED,
> + .menu_skip_mask = BIT(V4L2_MPEG_VIDEO_H264_DECODE_MODE_FRAME_BASED),

You don't need this: DECODE_MODE_FRAME_BASED > DECODE_MODE_SLICE_BASED (the max
value). So no need to set the skip_mask since it is out of range.

> + },
> + .codec = CEDRUS_CODEC_H264,
> + .required = false,
> + },
> + {
> + .cfg = {
> + .id = V4L2_CID_MPEG_VIDEO_H264_START_CODE,
> + .max = V4L2_MPEG_VIDEO_H264_START_CODE_NONE,
> + .def = V4L2_MPEG_VIDEO_H264_START_CODE_NONE,
> + .menu_skip_mask = BIT(V4L2_MPEG_VIDEO_H264_START_CODE_ANNEX_B),

Ditto.

Regards,

Hans

> + },
> + .codec = CEDRUS_CODEC_H264,
> + .required = false,
> + },
> };
>
> #define CEDRUS_CONTROLS_COUNT ARRAY_SIZE(cedrus_controls)
>