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Diffstat (limited to 'kernel/Documentation/DocBook/media/v4l/vidioc-querystd.xml')
-rw-r--r-- | kernel/Documentation/DocBook/media/v4l/vidioc-querystd.xml | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/kernel/Documentation/DocBook/media/v4l/vidioc-querystd.xml b/kernel/Documentation/DocBook/media/v4l/vidioc-querystd.xml new file mode 100644 index 000000000..222348542 --- /dev/null +++ b/kernel/Documentation/DocBook/media/v4l/vidioc-querystd.xml @@ -0,0 +1,75 @@ +<refentry id="vidioc-querystd"> + <refmeta> + <refentrytitle>ioctl VIDIOC_QUERYSTD</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>VIDIOC_QUERYSTD</refname> + <refpurpose>Sense the video standard received by the current +input</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcprototype> + <funcdef>int <function>ioctl</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>request</parameter></paramdef> + <paramdef>v4l2_std_id *<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_QUERYSTD</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + + <para>The hardware may be able to detect the current video +standard automatically. To do so, applications call <constant> +VIDIOC_QUERYSTD</constant> with a pointer to a &v4l2-std-id; type. The +driver stores here a set of candidates, this can be a single flag or a +set of supported standards if for example the hardware can only +distinguish between 50 and 60 Hz systems. If no signal was detected, +then the driver will return V4L2_STD_UNKNOWN. When detection is not +possible or fails, the set must contain all standards supported by the +current video input or output.</para> + + </refsect1> + + <refsect1> + &return-value; + <variablelist> + <varlistentry> + <term><errorcode>ENODATA</errorcode></term> + <listitem> + <para>Standard video timings are not supported for this input or output.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> |