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Diffstat (limited to 'Documentation/DocBook/v4l/vidioc-streamon.xml')
-rw-r--r-- | Documentation/DocBook/v4l/vidioc-streamon.xml | 115 |
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diff --git a/Documentation/DocBook/v4l/vidioc-streamon.xml b/Documentation/DocBook/v4l/vidioc-streamon.xml deleted file mode 100644 index 75ed39bf4d2b..000000000000 --- a/Documentation/DocBook/v4l/vidioc-streamon.xml +++ /dev/null @@ -1,115 +0,0 @@ -<refentry id="vidioc-streamon"> - <refmeta> - <refentrytitle>ioctl VIDIOC_STREAMON, VIDIOC_STREAMOFF</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_STREAMON</refname> - <refname>VIDIOC_STREAMOFF</refname> - <refpurpose>Start or stop streaming I/O</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>const int *<parameter>argp</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Arguments</title> - - <variablelist> - <varlistentry> - <term><parameter>fd</parameter></term> - <listitem> - <para>&fd;</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>request</parameter></term> - <listitem> - <para>VIDIOC_STREAMON, VIDIOC_STREAMOFF</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>The <constant>VIDIOC_STREAMON</constant> and -<constant>VIDIOC_STREAMOFF</constant> ioctl start and stop the capture -or output process during streaming (<link linkend="mmap">memory -mapping</link> or <link linkend="userp">user pointer</link>) I/O.</para> - - <para>Specifically the capture hardware is disabled and no input -buffers are filled (if there are any empty buffers in the incoming -queue) until <constant>VIDIOC_STREAMON</constant> has been called. -Accordingly the output hardware is disabled, no video signal is -produced until <constant>VIDIOC_STREAMON</constant> has been called. -The ioctl will succeed only when at least one output buffer is in the -incoming queue.</para> - - <para>The <constant>VIDIOC_STREAMOFF</constant> ioctl, apart of -aborting or finishing any DMA in progress, unlocks any user pointer -buffers locked in physical memory, and it removes all buffers from the -incoming and outgoing queues. That means all images captured but not -dequeued yet will be lost, likewise all images enqueued for output but -not transmitted yet. I/O returns to the same state as after calling -&VIDIOC-REQBUFS; and can be restarted accordingly.</para> - - <para>Both ioctls take a pointer to an integer, the desired buffer or -stream type. This is the same as &v4l2-requestbuffers; -<structfield>type</structfield>.</para> - - <para>Note applications can be preempted for unknown periods right -before or after the <constant>VIDIOC_STREAMON</constant> or -<constant>VIDIOC_STREAMOFF</constant> calls, there is no notion of -starting or stopping "now". Buffer timestamps can be used to -synchronize with other events.</para> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>Streaming I/O is not supported, the buffer -<structfield>type</structfield> is not supported, or no buffers have -been allocated (memory mapping) or enqueued (output) yet.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EPIPE</errorcode></term> - <listitem> - <para>The driver implements <link - linkend="pad-level-formats">pad-level format configuration</link> and - the pipeline configuration is invalid. - </para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> - -<!-- -Local Variables: -mode: sgml -sgml-parent-document: "v4l2.sgml" -indent-tabs-mode: nil -End: ---> |