Am Montag, den 13.04.2015, 14:42 +0900 schrieb Pawel Osciak: > Hi, > Thanks for working on this! > > On Wed, Mar 25, 2015 at 2:46 AM, Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> wrote: > > From: Peter Seiderer <ps.report@xxxxxxx> > > > > This v4l2_buffer flag can be used by drivers to mark a capture buffer > > as the last generated buffer, for example after a V4L2_DEC_CMD_STOP > > command was issued. > > The DocBook is updated to mention mem2mem codecs and the mem2mem draining flow > > signals in the VIDIOC_DECODER_CMD V4L2_DEC_CMD_STOP and VIDIOC_ENCODER_CMD > > V4L2_ENC_CMD_STOP documentation. > > > > Signed-off-by: Peter Seiderer <ps.report@xxxxxxx> > > Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> > > --- > > Changes since v3: > > - Added DocBook update mentioning V4L2_BUF_FLAG_LAST in the encoder/decoder > > stop command documentation. > > --- > > Documentation/DocBook/media/v4l/io.xml | 10 ++++++++++ > > Documentation/DocBook/media/v4l/vidioc-decoder-cmd.xml | 6 +++++- > > Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml | 5 ++++- > > include/trace/events/v4l2.h | 3 ++- > > include/uapi/linux/videodev2.h | 2 ++ > > 5 files changed, 23 insertions(+), 3 deletions(-) > > > > diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml > > index 1c17f80..f3b8bc0 100644 > > --- a/Documentation/DocBook/media/v4l/io.xml > > +++ b/Documentation/DocBook/media/v4l/io.xml > > @@ -1129,6 +1129,16 @@ in this buffer has not been created by the CPU but by some DMA-capable unit, > > in which case caches have not been used.</entry> > > </row> > > <row> > > + <entry><constant>V4L2_BUF_FLAG_LAST</constant></entry> > > + <entry>0x00100000</entry> > > + <entry>Last buffer produced by the hardware. mem2mem codec drivers > > +set this flag on the capture queue for the last buffer when the > > +<link linkend="vidioc-querybuf">VIDIOC_QUERYBUF</link> or > > +<link linkend="vidioc-qbuf">VIDIOC_DQBUF</link> ioctl is called. After the > > +queue is drained, the <link linkend="vidioc-qbuf">VIDIOC_DQBUF</link> ioctl will > > Perhaps just s/After the queue is drained, the/Any subsequent/ ? This > would make it more clear I feel. > DQBUF of LAST is the end of draining. Concise, I like it. > > +not block anymore, but return an &EPIPE;.</entry> > > + </row> > > + <row> > > <entry><constant>V4L2_BUF_FLAG_TIMESTAMP_MASK</constant></entry> > > <entry>0x0000e000</entry> > > <entry>Mask for timestamp types below. To test the > > diff --git a/Documentation/DocBook/media/v4l/vidioc-decoder-cmd.xml b/Documentation/DocBook/media/v4l/vidioc-decoder-cmd.xml > > index 9215627..cbb7135 100644 > > --- a/Documentation/DocBook/media/v4l/vidioc-decoder-cmd.xml > > +++ b/Documentation/DocBook/media/v4l/vidioc-decoder-cmd.xml > > @@ -197,7 +197,11 @@ be muted when playing back at a non-standard speed. > > this command does nothing. This command has two flags: > > if <constant>V4L2_DEC_CMD_STOP_TO_BLACK</constant> is set, then the decoder will > > set the picture to black after it stopped decoding. Otherwise the last image will > > -repeat. If <constant>V4L2_DEC_CMD_STOP_IMMEDIATELY</constant> is set, then the decoder > > +repeat. mem2mem decoders will stop producing new frames altogether. They will send > > +a <constant>V4L2_EVENT_EOS</constant> event after the last frame was decoded and > > s/was decoded/has been decoded and all frames are ready to be dequeued/ Yes. > > +will set the <constant>V4L2_BUF_FLAG_LAST</constant> buffer flag when there will > > +be no new buffers produced to dequeue. > > To make the timing description more explicit, s/when there will be no > new buffers produced to dequeue./on the final buffer being dequeued/ > perhaps? > EOS indicates "no more buffers will be produced and all are ready to > be dequeued", while LAST indicates "final buffer being dequeued". Yes. > > +If <constant>V4L2_DEC_CMD_STOP_IMMEDIATELY</constant> is set, then the decoder > > stops immediately (ignoring the <structfield>pts</structfield> value), otherwise it > > will keep decoding until timestamp >= pts or until the last of the pending data from > > its internal buffers was decoded. > > diff --git a/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml b/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml > > index 0619ca5..e9cf601 100644 > > --- a/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml > > +++ b/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml > > @@ -129,7 +129,10 @@ this command.</entry> > > encoding will continue until the end of the current <wordasword>Group > > Of Pictures</wordasword>, otherwise encoding will stop immediately. > > When the encoder is already stopped, this command does > > -nothing.</entry> > > +nothing. mem2mem encoders will send a <constant>V4L2_EVENT_EOS</constant> event > > +after the last frame was encoded and will set the > > +<constant>V4L2_BUF_FLAG_LAST</constant> buffer flag on the capture queue when > > +there will be no new buffers produced to dequeue</entry> > > I'd propose the same here. And yes. Thanks, I'll make those changes. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
