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Diffstat (limited to 'Documentation/DocBook/v4l/vidioc-enumoutput.xml')
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diff --git a/Documentation/DocBook/v4l/vidioc-enumoutput.xml b/Documentation/DocBook/v4l/vidioc-enumoutput.xml new file mode 100644 index 000000000000..e8d16dcd50cf --- /dev/null +++ b/Documentation/DocBook/v4l/vidioc-enumoutput.xml @@ -0,0 +1,172 @@ +<refentry id="vidioc-enumoutput"> + <refmeta> + <refentrytitle>ioctl VIDIOC_ENUMOUTPUT</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>VIDIOC_ENUMOUTPUT</refname> + <refpurpose>Enumerate video outputs</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_output *<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_ENUMOUTPUT</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + + <para>To query the attributes of a video outputs applications +initialize the <structfield>index</structfield> field of &v4l2-output; +and call the <constant>VIDIOC_ENUMOUTPUT</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 +outputs applications shall begin at index zero, incrementing by one +until the driver returns <errorcode>EINVAL</errorcode>.</para> + + <table frame="none" pgwide="1" id="v4l2-output"> + <title>struct <structname>v4l2_output</structname></title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>index</structfield></entry> + <entry>Identifies the output, set by the +application.</entry> + </row> + <row> + <entry>__u8</entry> + <entry><structfield>name</structfield>[32]</entry> + <entry>Name of the video output, a NUL-terminated ASCII +string, for example: "Vout". This information is intended for the +user, preferably the connector label on the device itself.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>type</structfield></entry> + <entry>Type of the output, see <xref + linkend="output-type" />.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>audioset</structfield></entry> + <entry><para>Drivers can enumerate up to 32 video and +audio outputs. This field shows which audio outputs were +selectable as the current output if this was the currently selected +video output. It is a bit mask. The LSB corresponds to audio output 0, +the MSB to output 31. Any number of bits can be set, or +none.</para><para>When the driver does not enumerate audio outputs no +bits must be set. Applications shall not interpret this as lack of +audio support. Drivers may automatically select audio outputs without +enumerating them.</para><para>For details on audio outputs and how to +select the current output see <xref linkend="audio" />.</para></entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>modulator</structfield></entry> + <entry>Output devices can have zero or more RF modulators. +When the <structfield>type</structfield> is +<constant>V4L2_OUTPUT_TYPE_MODULATOR</constant> this is an RF +connector and this field identifies the modulator. It corresponds to +&v4l2-modulator; field <structfield>index</structfield>. For details +on modulators see <xref linkend="tuner" />.</entry> + </row> + <row> + <entry>&v4l2-std-id;</entry> + <entry><structfield>std</structfield></entry> + <entry>Every video output supports one or more different +video standards. This field is a set of all supported standards. For +details on video standards and how to switch see <xref + linkend="standard" />.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[4]</entry> + <entry>Reserved for future extensions. Drivers must set +the array to zero.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table frame="none" pgwide="1" id="output-type"> + <title>Output Type</title> + <tgroup cols="3"> + &cs-def; + <tbody valign="top"> + <row> + <entry><constant>V4L2_OUTPUT_TYPE_MODULATOR</constant></entry> + <entry>1</entry> + <entry>This output is an analog TV modulator.</entry> + </row> + <row> + <entry><constant>V4L2_OUTPUT_TYPE_ANALOG</constant></entry> + <entry>2</entry> + <entry>Analog baseband output, for example Composite / +CVBS, S-Video, RGB.</entry> + </row> + <row> + <entry><constant>V4L2_OUTPUT_TYPE_ANALOGVGAOVERLAY</constant></entry> + <entry>3</entry> + <entry>[?]</entry> + </row> + </tbody> + </tgroup> + </table> + + </refsect1> + <refsect1> + &return-value; + + <variablelist> + <varlistentry> + <term><errorcode>EINVAL</errorcode></term> + <listitem> + <para>The &v4l2-output; <structfield>index</structfield> +is out of bounds.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> + +<!-- +Local Variables: +mode: sgml +sgml-parent-document: "v4l2.sgml" +indent-tabs-mode: nil +End: +--> |