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-rw-r--r--Documentation/DocBook/media/v4l/io.xml26
1 files changed, 19 insertions, 7 deletions
diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml
index 1c17f802b471..7bbc2a48911e 100644
--- a/Documentation/DocBook/media/v4l/io.xml
+++ b/Documentation/DocBook/media/v4l/io.xml
@@ -841,15 +841,15 @@ is the file descriptor associated with a DMABUF buffer.</entry>
<entry>__u32</entry>
<entry><structfield>reserved2</structfield></entry>
<entry></entry>
- <entry>A place holder for future extensions. Applications
-should set this to 0.</entry>
+ <entry>A place holder for future extensions. Drivers and applications
+must set this to 0.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>reserved</structfield></entry>
<entry></entry>
- <entry>A place holder for future extensions. Applications
-should set this to 0.</entry>
+ <entry>A place holder for future extensions. Drivers and applications
+must set this to 0.</entry>
</row>
</tbody>
</tgroup>
@@ -930,8 +930,8 @@ should set this to 0.</entry>
<entry>__u32</entry>
<entry><structfield>reserved[11]</structfield></entry>
<entry></entry>
- <entry>Reserved for future use. Should be zeroed by an
- application.</entry>
+ <entry>Reserved for future use. Should be zeroed by drivers and
+ applications.</entry>
</row>
</tbody>
</tgroup>
@@ -1129,6 +1129,18 @@ 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. Due to hardware
+limitations, the last buffer may be empty. In this case the driver will set the
+<structfield>bytesused</structfield> field to 0, regardless of the format. Any
+Any subsequent call to the <link linkend="vidioc-qbuf">VIDIOC_DQBUF</link> ioctl
+will 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
@@ -1155,7 +1167,7 @@ in which case caches have not been used.</entry>
<entry>The buffer timestamp has been taken from the
<constant>CLOCK_MONOTONIC</constant> clock. To access the
same clock outside V4L2, use
- <function>clock_gettime(2)</function> .</entry>
+ <function>clock_gettime(2)</function>.</entry>
</row>
<row>
<entry><constant>V4L2_BUF_FLAG_TIMESTAMP_COPY</constant></entry>