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+<refentry id="media-ioc-setup-link">
+ <refmeta>
+ <refentrytitle>ioctl MEDIA_IOC_SETUP_LINK</refentrytitle>
+ &manvol;
+ </refmeta>
+
+ <refnamediv>
+ <refname>MEDIA_IOC_SETUP_LINK</refname>
+ <refpurpose>Modify the properties of a link</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 media_link_desc *<parameter>argp</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Arguments</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><parameter>fd</parameter></term>
+ <listitem>
+ <para>File descriptor returned by
+ <link linkend='media-func-open'><function>open()</function></link>.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>request</parameter></term>
+ <listitem>
+ <para>MEDIA_IOC_SETUP_LINK</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>argp</parameter></term>
+ <listitem>
+ <para></para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>To change link properties applications fill a &media-link-desc; with
+ link identification information (source and sink pad) and the new requested
+ link flags. They then call the MEDIA_IOC_SETUP_LINK ioctl with a pointer to
+ that structure.</para>
+ <para>The only configurable property is the <constant>ENABLED</constant>
+ link flag to enable/disable a link. Links marked with the
+ <constant>IMMUTABLE</constant> link flag can not be enabled or disabled.
+ </para>
+ <para>Link configuration has no side effect on other links. If an enabled
+ link at the sink pad prevents the link from being enabled, the driver
+ returns with an &EBUSY;.</para>
+ <para>Only links marked with the <constant>DYNAMIC</constant> link flag can
+ be enabled/disabled while streaming media data. Attempting to enable or
+ disable a streaming non-dynamic link will return an &EBUSY;.</para>
+ <para>If the specified link can't be found the driver returns with an
+ &EINVAL;.</para>
+ </refsect1>
+
+ <refsect1>
+ &return-value;
+
+ <variablelist>
+ <varlistentry>
+ <term><errorcode>EINVAL</errorcode></term>
+ <listitem>
+ <para>The &media-link-desc; references a non-existing link, or the
+ link is immutable and an attempt to modify its configuration was made.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+</refentry>