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-rw-r--r--Documentation/DocBook/media/v4l/vidioc-querybuf.xml11
1 files changed, 7 insertions, 4 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-querybuf.xml b/Documentation/DocBook/media/v4l/vidioc-querybuf.xml
index 6e414d7b6df..a597155c052 100644
--- a/Documentation/DocBook/media/v4l/vidioc-querybuf.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-querybuf.xml
@@ -48,8 +48,8 @@
<refsect1>
<title>Description</title>
- <para>This ioctl is part of the <link linkend="mmap">memory
-mapping</link> I/O method. It can be used to query the status of a
+ <para>This ioctl is part of the <link linkend="mmap">streaming
+</link> I/O method. It can be used to query the status of a
buffer at any time after buffers have been allocated with the
&VIDIOC-REQBUFS; ioctl.</para>
@@ -71,6 +71,7 @@ the structure.</para>
<para>In the <structfield>flags</structfield> field the
<constant>V4L2_BUF_FLAG_MAPPED</constant>,
+<constant>V4L2_BUF_FLAG_PREPARED</constant>,
<constant>V4L2_BUF_FLAG_QUEUED</constant> and
<constant>V4L2_BUF_FLAG_DONE</constant> flags will be valid. The
<structfield>memory</structfield> field will be set to the current
@@ -79,8 +80,10 @@ contains the offset of the buffer from the start of the device memory,
the <structfield>length</structfield> field its size. For the multi-planar API,
fields <structfield>m.mem_offset</structfield> and
<structfield>length</structfield> in the <structfield>m.planes</structfield>
-array elements will be used instead. The driver may or may not set the remaining
-fields and flags, they are meaningless in this context.</para>
+array elements will be used instead and the <structfield>length</structfield>
+field of &v4l2-buffer; is set to the number of filled-in array elements.
+The driver may or may not set the remaining fields and flags, they are
+meaningless in this context.</para>
<para>The <structname>v4l2_buffer</structname> structure is
specified in <xref linkend="buffer" />.</para>