Hello, Thank you for review. Please refer to comments below.
On 04/05/2012 04:58 PM, Rémi Denis-Courmont wrote:
Le jeudi 5 avril 2012 16:59:59 Tomasz Stanislawski, vous avez écrit :
This patch adds description and usage examples for importing DMABUF file descriptor in V4L2.
Signed-off-by: Tomasz Stanislawski t.stanislaws@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com
Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/io.xml | 177 ++++++++++++++++++++ .../DocBook/media/v4l/vidioc-create-bufs.xml | 1 + Documentation/DocBook/media/v4l/vidioc-qbuf.xml | 15 ++ Documentation/DocBook/media/v4l/vidioc-reqbufs.xml | 8 +- 5 files changed, 203 insertions(+), 2 deletions(-)
[snip]
<example>
<title>Initiating streaming I/O with DMABUF file descriptors</title><programlisting>+&v4l2-requestbuffers; reqbuf;
+memset (&reqbuf, 0, sizeof (reqbuf)); +reqbuf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; +reqbuf.memory = V4L2_MEMORY_DMABUF;
+if (ioctl (fd, &VIDIOC-REQBUFS;, &reqbuf) == -1) {
- if (errno == EINVAL)
printf ("Video capturing or user pointer streaming is notsupported\n");
User pointer??
Right. I will fix this copy & paste error.
- else
perror ("VIDIOC_REQBUFS");- exit (EXIT_FAILURE);
+}
</programlisting></example>
[snip]
- <para>To start and stop capturing or output applications call the
+&VIDIOC-STREAMON; and &VIDIOC-STREAMOFF; ioctl. Note +<constant>VIDIOC_STREAMOFF</constant> removes all buffers from both queues and +unlocks/unpins all buffers as a side effect. Since there is no notion of doing +anything "now" on a multitasking system, if an application needs to synchronize +with another event it should examine the &v4l2-buffer; +<structfield>timestamp</structfield> of captured buffers, or set the field +before enqueuing buffers for output.</para>
- <para>Drivers implementing user pointer I/O must support the
User pointer again??
Yes. Another C&P mistake. Thanks for noticing it.
Regards, Tomasz Stanislawski