<refentry id="vidioc-enum-dv-timings"> <refmeta> <refentrytitle>ioctl VIDIOC_ENUM_DV_TIMINGS</refentrytitle> &manvol; </refmeta> <refnamediv> <refname>VIDIOC_ENUM_DV_TIMINGS</refname> <refpurpose>Enumerate supported Digital Video timings</refpurpose> </refnamediv> <refsynopsisdiv> <funcsynopsis> <funcprototype> <funcdef>int <function>ioctl</function></funcdef> <paramdef>int <parameter>fd</parameter></paramdef> <paramdef>int <parameter>request</parameter></paramdef> <paramdef>struct v4l2_enum_dv_timings *<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_ENUM_DV_TIMINGS</para> </listitem> </varlistentry> <varlistentry> <term><parameter>argp</parameter></term> <listitem> <para></para> </listitem> </varlistentry> </variablelist> </refsect1> <refsect1> <title>Description</title> <note> <title>Experimental</title> <para>This is an <link linkend="experimental"> experimental </link> interface and may change in the future.</para> </note> <para>While some DV receivers or transmitters support a wide range of timings, others support only a limited number of timings. With this ioctl applications can enumerate a list of known supported timings. Call &VIDIOC-DV-TIMINGS-CAP; to check if it also supports other standards or even custom timings that are not in this list.</para> <para>To query the available timings, applications initialize the <structfield>index</structfield> field and zero the reserved array of &v4l2-enum-dv-timings; and call the <constant>VIDIOC_ENUM_DV_TIMINGS</constant> ioctl with a pointer to this structure. Drivers fill the rest of the structure or return an &EINVAL; when the index is out of bounds. To enumerate all supported DV timings, applications shall begin at index zero, incrementing by one until the driver returns <errorcode>EINVAL</errorcode>. Note that drivers may enumerate a different set of DV timings after switching the video input or output.</para> <table pgwide="1" frame="none" id="v4l2-enum-dv-timings"> <title>struct <structname>v4l2_enum_dv_timings</structname></title> <tgroup cols="3"> &cs-str; <tbody valign="top"> <row> <entry>__u32</entry> <entry><structfield>index</structfield></entry> <entry>Number of the DV timings, set by the application.</entry> </row> <row> <entry>__u32</entry> <entry><structfield>reserved</structfield>[3]</entry> <entry>Reserved for future extensions. Drivers must set the array to zero.</entry> </row> <row> <entry>&v4l2-dv-timings;</entry> <entry><structfield>timings</structfield></entry> <entry>The timings.</entry> </row> </tbody> </tgroup> </table> </refsect1> <refsect1> &return-value; <variablelist> <varlistentry> <term><errorcode>EINVAL</errorcode></term> <listitem> <para>The &v4l2-enum-dv-timings; <structfield>index</structfield> is out of bounds.</para> </listitem> </varlistentry> <varlistentry> <term><errorcode>ENODATA</errorcode></term> <listitem> <para>Digital video presets are not supported for this input or output.</para> </listitem> </varlistentry> </variablelist> </refsect1> </refentry> <!-- Local Variables: mode: sgml sgml-parent-document: "v4l2.sgml" indent-tabs-mode: nil End: -->