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| author | Guennadi Liakhovetski <g.liakhovetski@gmx.de> | 2011-09-28 13:10:58 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2011-11-03 21:28:27 +0100 |
| commit | 55093284fb6f9009a339e522773417bdd54ec144 (patch) | |
| tree | c9c91afddcec2fd5890e003e19558f7aa2018979 /Documentation/DocBook/media/v4l/io.xml | |
| parent | [media] V4L: videobuf2: update buffer state on VIDIOC_QBUF (diff) | |
| download | linux-55093284fb6f9009a339e522773417bdd54ec144.tar.xz linux-55093284fb6f9009a339e522773417bdd54ec144.zip | |
[media] V4L: document the new VIDIOC_CREATE_BUFS and VIDIOC_PREPARE_BUF ioctl()s
[mchehab@redhat.com: remove emacs format crap at the end of the new files]
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'Documentation/DocBook/media/v4l/io.xml')
| -rw-r--r-- | Documentation/DocBook/media/v4l/io.xml | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml index c57d1ec6291c..3f47df1aa54a 100644 --- a/Documentation/DocBook/media/v4l/io.xml +++ b/Documentation/DocBook/media/v4l/io.xml @@ -927,6 +927,33 @@ ioctl is called.</entry> Applications set or clear this flag before calling the <constant>VIDIOC_QBUF</constant> ioctl.</entry> </row> + <row> + <entry><constant>V4L2_BUF_FLAG_PREPARED</constant></entry> + <entry>0x0400</entry> + <entry>The buffer has been prepared for I/O and can be queued by the +application. Drivers set or clear this flag when the +<link linkend="vidioc-querybuf">VIDIOC_QUERYBUF</link>, <link + linkend="vidioc-qbuf">VIDIOC_PREPARE_BUF</link>, <link + linkend="vidioc-qbuf">VIDIOC_QBUF</link> or <link + linkend="vidioc-qbuf">VIDIOC_DQBUF</link> ioctl is called.</entry> + </row> + <row> + <entry><constant>V4L2_BUF_FLAG_NO_CACHE_INVALIDATE</constant></entry> + <entry>0x0400</entry> + <entry>Caches do not have to be invalidated for this buffer. +Typically applications shall use this flag if the data captured in the buffer +is not going to be touched by the CPU, instead the buffer will, probably, be +passed on to a DMA-capable hardware unit for further processing or output. +</entry> + </row> + <row> + <entry><constant>V4L2_BUF_FLAG_NO_CACHE_CLEAN</constant></entry> + <entry>0x0800</entry> + <entry>Caches do not have to be cleaned for this buffer. +Typically applications shall use this flag for output buffers if the data +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> </tbody> </tgroup> </table> |