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Based on kernel version 3.16. Page generated on 2014-08-06 21:38 EST.

1	<refentry id="media-ioc-setup-link">
2	  <refmeta>
3	    <refentrytitle>ioctl MEDIA_IOC_SETUP_LINK</refentrytitle>
4	    &manvol;
5	  </refmeta>
6	
7	  <refnamediv>
8	    <refname>MEDIA_IOC_SETUP_LINK</refname>
9	    <refpurpose>Modify the properties of a link</refpurpose>
10	  </refnamediv>
11	
12	  <refsynopsisdiv>
13	    <funcsynopsis>
14	      <funcprototype>
15		<funcdef>int <function>ioctl</function></funcdef>
16		<paramdef>int <parameter>fd</parameter></paramdef>
17		<paramdef>int <parameter>request</parameter></paramdef>
18		<paramdef>struct media_link_desc *<parameter>argp</parameter></paramdef>
19	      </funcprototype>
20	    </funcsynopsis>
21	  </refsynopsisdiv>
22	
23	  <refsect1>
24	    <title>Arguments</title>
25	
26	    <variablelist>
27	      <varlistentry>
28		<term><parameter>fd</parameter></term>
29		<listitem>
30		  <para>File descriptor returned by
31		  <link linkend='media-func-open'><function>open()</function></link>.</para>
32		</listitem>
33	      </varlistentry>
34	      <varlistentry>
35		<term><parameter>request</parameter></term>
36		<listitem>
37		  <para>MEDIA_IOC_SETUP_LINK</para>
38		</listitem>
39	      </varlistentry>
40	      <varlistentry>
41		<term><parameter>argp</parameter></term>
42		<listitem>
43		  <para></para>
44		</listitem>
45	      </varlistentry>
46	    </variablelist>
47	  </refsect1>
48	
49	  <refsect1>
50	    <title>Description</title>
51	
52	    <para>To change link properties applications fill a &media-link-desc; with
53	    link identification information (source and sink pad) and the new requested
54	    link flags. They then call the MEDIA_IOC_SETUP_LINK ioctl with a pointer to
55	    that structure.</para>
56	    <para>The only configurable property is the <constant>ENABLED</constant>
57	    link flag to enable/disable a link. Links marked with the
58	    <constant>IMMUTABLE</constant> link flag can not be enabled or disabled.
59	    </para>
60	    <para>Link configuration has no side effect on other links. If an enabled
61	    link at the sink pad prevents the link from being enabled, the driver
62	    returns with an &EBUSY;.</para>
63	    <para>Only links marked with the <constant>DYNAMIC</constant> link flag can
64	    be enabled/disabled while streaming media data. Attempting to enable or
65	    disable a streaming non-dynamic link will return an &EBUSY;.</para>
66	    <para>If the specified link can't be found the driver returns with an
67	    &EINVAL;.</para>
68	  </refsect1>
69	
70	  <refsect1>
71	    &return-value;
72	
73	    <variablelist>
74	      <varlistentry>
75		<term><errorcode>EINVAL</errorcode></term>
76		<listitem>
77		  <para>The &media-link-desc; references a non-existing link, or the
78		  link is immutable and an attempt to modify its configuration was made.
79		  </para>
80		</listitem>
81	      </varlistentry>
82	    </variablelist>
83	  </refsect1>
84	</refentry>
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