On 8/15/19 10:12 AM, Alexandre Courbot wrote:
> On Mon, Aug 12, 2019 at 8:07 PM Hans Verkuil <[email protected]> wrote:
>>
>> Add this new V4L2_DEC_CMD_FLUSH decoder command and document it.
>>
>> Signed-off-by: Hans Verkuil <[email protected]>
>> ---
>> Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst | 11 ++++++++++-
>> Documentation/media/videodev2.h.rst.exceptions | 1 +
>> include/uapi/linux/videodev2.h | 1 +
>> 3 files changed, 12 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
>> b/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
>> index 57f0066f4cff..0bffef6058f7 100644
>> --- a/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
>> +++ b/Documentation/media/uapi/v4l/vidioc-decoder-cmd.rst
>> @@ -208,7 +208,16 @@ introduced in Linux 3.3. They are, however, mandatory
>> for stateful mem2mem decod
>> been started yet, the driver will return an ``EPERM`` error code.
>> When
>> the decoder is already running, this command does nothing. No
>> flags are defined for this command.
>> -
>> + * - ``V4L2_DEC_CMD_FLUSH``
>> + - 4
>> + - Flush any held capture buffers. Only valid for stateless decoders,
>> + and only if ``V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF`` was set.
>> + This command is typically used when the application reached the
>> + end of the stream and the last output buffer had the
>> + ``V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF`` flag set. This would prevent
>> + dequeueing the last capture buffer containing the last decoded frame.
>> + So this command can be used to explicitly flush that last decoded
>> + frame.
>
> I'm a bit confused here, isn't this command referred to as
> V4L2_DEC_CMD_STOP in the previous patch?
That was a typo in the previous patch. It really is FLUSH.
Regards,
Hans
>
>
>>
>> Return Value
>> ============
>> diff --git a/Documentation/media/videodev2.h.rst.exceptions
>> b/Documentation/media/videodev2.h.rst.exceptions
>> index adeb6b7a15cb..a79028e4d929 100644
>> --- a/Documentation/media/videodev2.h.rst.exceptions
>> +++ b/Documentation/media/videodev2.h.rst.exceptions
>> @@ -434,6 +434,7 @@ replace define V4L2_DEC_CMD_START decoder-cmds
>> replace define V4L2_DEC_CMD_STOP decoder-cmds
>> replace define V4L2_DEC_CMD_PAUSE decoder-cmds
>> replace define V4L2_DEC_CMD_RESUME decoder-cmds
>> +replace define V4L2_DEC_CMD_FLUSH decoder-cmds
>>
>> replace define V4L2_DEC_CMD_START_MUTE_AUDIO decoder-cmds
>> replace define V4L2_DEC_CMD_PAUSE_TO_BLACK decoder-cmds
>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>> index 4fa9f543742d..91a79e16089c 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -1978,6 +1978,7 @@ struct v4l2_encoder_cmd {
>> #define V4L2_DEC_CMD_STOP (1)
>> #define V4L2_DEC_CMD_PAUSE (2)
>> #define V4L2_DEC_CMD_RESUME (3)
>> +#define V4L2_DEC_CMD_FLUSH (4)
>>
>> /* Flags for V4L2_DEC_CMD_START */
>> #define V4L2_DEC_CMD_START_MUTE_AUDIO (1 << 0)
>> --
>> 2.20.1
>>
