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-rw-r--r--Documentation/DocBook/media/v4l/compat.xml20
-rw-r--r--Documentation/DocBook/media/v4l/func-poll.xml35
-rw-r--r--Documentation/DocBook/media/v4l/v4l2.xml11
-rw-r--r--Documentation/DocBook/media/v4l/vidioc-subdev-g-selection.xml2
4 files changed, 56 insertions, 12 deletions
diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml
index 7aa7c5d41e3b..07ffc76553ba 100644
--- a/Documentation/DocBook/media/v4l/compat.xml
+++ b/Documentation/DocBook/media/v4l/compat.xml
@@ -2546,6 +2546,26 @@ fields changed from _s32 to _u32.
</section>
<section>
+ <title>V4L2 in Linux 3.16</title>
+ <orderedlist>
+ <listitem>
+ <para>Added event V4L2_EVENT_SOURCE_CHANGE.
+ </para>
+ </listitem>
+ </orderedlist>
+ </section>
+
+ <section>
+ <title>V4L2 in Linux 3.17</title>
+ <orderedlist>
+ <listitem>
+ <para>Extended &v4l2-pix-format;. Added format flags.
+ </para>
+ </listitem>
+ <listitem>
+ <para>Added compound control types and &VIDIOC-QUERY-EXT-CTRL;.
+ </para>
+ </listitem>
<title>V4L2 in Linux 3.18</title>
<orderedlist>
<listitem>
diff --git a/Documentation/DocBook/media/v4l/func-poll.xml b/Documentation/DocBook/media/v4l/func-poll.xml
index 85cad8bff5ba..4c73f115219b 100644
--- a/Documentation/DocBook/media/v4l/func-poll.xml
+++ b/Documentation/DocBook/media/v4l/func-poll.xml
@@ -29,9 +29,12 @@ can suspend execution until the driver has captured data or is ready
to accept data for output.</para>
<para>When streaming I/O has been negotiated this function waits
-until a buffer has been filled or displayed and can be dequeued with
-the &VIDIOC-DQBUF; ioctl. When buffers are already in the outgoing
-queue of the driver the function returns immediately.</para>
+until a buffer has been filled by the capture device and can be dequeued
+with the &VIDIOC-DQBUF; ioctl. For output devices this function waits
+until the device is ready to accept a new buffer to be queued up with
+the &VIDIOC-QBUF; ioctl for display. When buffers are already in the outgoing
+queue of the driver (capture) or the incoming queue isn't full (display)
+the function returns immediately.</para>
<para>On success <function>poll()</function> returns the number of
file descriptors that have been selected (that is, file descriptors
@@ -44,10 +47,22 @@ Capture devices set the <constant>POLLIN</constant> and
flags. When the function timed out it returns a value of zero, on
failure it returns <returnvalue>-1</returnvalue> and the
<varname>errno</varname> variable is set appropriately. When the
-application did not call &VIDIOC-QBUF; or &VIDIOC-STREAMON; yet the
+application did not call &VIDIOC-STREAMON; the
<function>poll()</function> function succeeds, but sets the
<constant>POLLERR</constant> flag in the
-<structfield>revents</structfield> field.</para>
+<structfield>revents</structfield> field. When the
+application has called &VIDIOC-STREAMON; for a capture device but hasn't
+yet called &VIDIOC-QBUF;, the <function>poll()</function> function
+succeeds and sets the <constant>POLLERR</constant> flag in the
+<structfield>revents</structfield> field. For output devices this
+same situation will cause <function>poll()</function> to succeed
+as well, but it sets the <constant>POLLOUT</constant> and
+<constant>POLLWRNORM</constant> flags in the <structfield>revents</structfield>
+field.</para>
+
+ <para>If an event occurred (see &VIDIOC-DQEVENT;) then
+<constant>POLLPRI</constant> will be set in the <structfield>revents</structfield>
+field and <function>poll()</function> will return.</para>
<para>When use of the <function>read()</function> function has
been negotiated and the driver does not capture yet, the
@@ -58,10 +73,18 @@ continuously (as opposed to, for example, still images) the function
may return immediately.</para>
<para>When use of the <function>write()</function> function has
-been negotiated the <function>poll</function> function just waits
+been negotiated and the driver does not stream yet, the
+<function>poll</function> function starts streaming. When that fails
+it returns a <constant>POLLERR</constant> as above. Otherwise it waits
until the driver is ready for a non-blocking
<function>write()</function> call.</para>
+ <para>If the caller is only interested in events (just
+<constant>POLLPRI</constant> is set in the <structfield>events</structfield>
+field), then <function>poll()</function> will <emphasis>not</emphasis>
+start streaming if the driver does not stream yet. This makes it
+possible to just poll for events and not for buffers.</para>
+
<para>All drivers implementing the <function>read()</function> or
<function>write()</function> function or streaming I/O must also
support the <function>poll()</function> function.</para>
diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml
index f2f81f06a17b..7cfe618f754d 100644
--- a/Documentation/DocBook/media/v4l/v4l2.xml
+++ b/Documentation/DocBook/media/v4l/v4l2.xml
@@ -152,10 +152,11 @@ structs, ioctls) must be noted in more detail in the history chapter
applications. -->
<revision>
- <revnumber>3.16</revnumber>
- <date>2014-05-27</date>
- <authorinitials>lp</authorinitials>
- <revremark>Extended &v4l2-pix-format;. Added format flags.
+ <revnumber>3.17</revnumber>
+ <date>2014-08-04</date>
+ <authorinitials>lp, hv</authorinitials>
+ <revremark>Extended &v4l2-pix-format;. Added format flags. Added compound control types
+and VIDIOC_QUERY_EXT_CTRL.
</revremark>
</revision>
@@ -538,7 +539,7 @@ and discussions on the V4L mailing list.</revremark>
</partinfo>
<title>Video for Linux Two API Specification</title>
- <subtitle>Revision 3.14</subtitle>
+ <subtitle>Revision 3.17</subtitle>
<chapter id="common">
&sub-common;
diff --git a/Documentation/DocBook/media/v4l/vidioc-subdev-g-selection.xml b/Documentation/DocBook/media/v4l/vidioc-subdev-g-selection.xml
index 1ba9e999af3f..c62a7360719b 100644
--- a/Documentation/DocBook/media/v4l/vidioc-subdev-g-selection.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-subdev-g-selection.xml
@@ -119,7 +119,7 @@
</row>
<row>
<entry>&v4l2-rect;</entry>
- <entry><structfield>rect</structfield></entry>
+ <entry><structfield>r</structfield></entry>
<entry>Selection rectangle, in pixels.</entry>
</row>
<row>