On 8/14/19 2:53 PM, Paul Kocialkowski wrote:
> Hi,
>
> On Mon 12 Aug 19, 13:05, Hans Verkuil wrote:
>> From: Maxime Jourdan <[email protected]>
>>
>> Add an enum_fmt format flag to specifically tag coded formats where
>> dynamic resolution switching is supported by the device.
>>
>> This is useful for some codec drivers that can support dynamic
>> resolution switching for one or more of their listed coded formats. It
>> allows userspace to know whether it should extract the video parameters
>> itself, or if it can rely on the device to send V4L2_EVENT_SOURCE_CHANGE
>> when such changes are detected.
>
> Makes sense and looks good to me:
> Reviewed-by: Paul Kocialkowski <[email protected]>
>
> The docs aren't saying that this only applies to stateful decoders, but I
> think
> it is quite clear that this can't apply to stateless decoders.
>
> Cheers,
>
> Paul
>
>> Signed-off-by: Maxime Jourdan <[email protected]>
>> Signed-off-by: Hans Verkuil <[email protected]>
>> [[email protected]: added flag to videodev2.h.rst.exceptions]
>> [[email protected]: updated commit text: 'one or more' instead of
>> 'all']
>> Acked-by: Tomasz Figa <[email protected]>
>> ---
>> Documentation/media/uapi/v4l/vidioc-enum-fmt.rst | 8 ++++++++
>> Documentation/media/videodev2.h.rst.exceptions | 1 +
>> include/uapi/linux/videodev2.h | 1 +
>> 3 files changed, 10 insertions(+)
>>
>> diff --git a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
>> b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
>> index ebc05ce74bdf..719f1ed64f7d 100644
>> --- a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
>> +++ b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
>> @@ -135,6 +135,14 @@ one until ``EINVAL`` is returned.
>> between frames/fields. This flag can only be used in combination with
>> the ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to compressed
>> formats only. This flag is valid for stateful decoders only.
>> + * - ``V4L2_FMT_FLAG_DYN_RESOLUTION``
>> + - 0x0008
>> + - Dynamic resolution switching is supported by the device for this
>> + compressed bytestream format (aka coded format). It will notify the user
>> + via the event ``V4L2_EVENT_SOURCE_CHANGE`` when changes in the video
>> + parameters are detected. This flag can only be used in combination
>> + with the ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to
>> + compressed formats only.
I added "It is also only applies to stateful codecs." at the end of this
paragraph.
Regards,
Hans
>>
>>
>> Return Value
>> diff --git a/Documentation/media/videodev2.h.rst.exceptions
>> b/Documentation/media/videodev2.h.rst.exceptions
>> index a0640b6d0f68..adeb6b7a15cb 100644
>> --- a/Documentation/media/videodev2.h.rst.exceptions
>> +++ b/Documentation/media/videodev2.h.rst.exceptions
>> @@ -181,6 +181,7 @@ replace define V4L2_PIX_FMT_FLAG_PREMUL_ALPHA
>> reserved-formats
>> replace define V4L2_FMT_FLAG_COMPRESSED fmtdesc-flags
>> replace define V4L2_FMT_FLAG_EMULATED fmtdesc-flags
>> replace define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM fmtdesc-flags
>> +replace define V4L2_FMT_FLAG_DYN_RESOLUTION fmtdesc-flags
>>
>> # V4L2 timecode types
>> replace define V4L2_TC_TYPE_24FPS timecode-type
>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>> index 67077d52c59d..530638dffd93 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -777,6 +777,7 @@ struct v4l2_fmtdesc {
>> #define V4L2_FMT_FLAG_COMPRESSED 0x0001
>> #define V4L2_FMT_FLAG_EMULATED 0x0002
>> #define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM 0x0004
>> +#define V4L2_FMT_FLAG_DYN_RESOLUTION 0x0008
>>
>> /* Frame Size and frame rate enumeration */
>> /*
>> --
>> 2.20.1
>>
>
