1<refentry id="vidioc-g-dv-preset">
2  <refmeta>
3    <refentrytitle>ioctl VIDIOC_G_DV_PRESET, VIDIOC_S_DV_PRESET</refentrytitle>
4    &manvol;
5  </refmeta>
6
7  <refnamediv>
8    <refname>VIDIOC_G_DV_PRESET</refname>
9    <refname>VIDIOC_S_DV_PRESET</refname>
10    <refpurpose>Query or select the DV preset of the current input or output</refpurpose>
11  </refnamediv>
12
13  <refsynopsisdiv>
14    <funcsynopsis>
15      <funcprototype>
16	<funcdef>int <function>ioctl</function></funcdef>
17	<paramdef>int <parameter>fd</parameter></paramdef>
18	<paramdef>int <parameter>request</parameter></paramdef>
19	<paramdef>struct v4l2_dv_preset *<parameter>argp</parameter></paramdef>
20      </funcprototype>
21    </funcsynopsis>
22  </refsynopsisdiv>
23
24  <refsect1>
25    <title>Arguments</title>
26
27    <variablelist>
28      <varlistentry>
29	<term><parameter>fd</parameter></term>
30	<listitem>
31	  <para>&fd;</para>
32	</listitem>
33      </varlistentry>
34      <varlistentry>
35	<term><parameter>request</parameter></term>
36	<listitem>
37	  <para>VIDIOC_G_DV_PRESET, VIDIOC_S_DV_PRESET</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    <para>To query and select the current DV preset, applications
52use the <constant>VIDIOC_G_DV_PRESET</constant> and <constant>VIDIOC_S_DV_PRESET</constant>
53ioctls which take a pointer to a &v4l2-dv-preset; type as argument.
54Applications must zero the reserved array in &v4l2-dv-preset;.
55<constant>VIDIOC_G_DV_PRESET</constant> returns a dv preset in the field
56<structfield>preset</structfield> of &v4l2-dv-preset;.</para>
57
58    <para><constant>VIDIOC_S_DV_PRESET</constant> accepts a pointer to a &v4l2-dv-preset;
59that has the preset value to be set. Applications must zero the reserved array in &v4l2-dv-preset;.
60If the preset is not supported, it returns an &EINVAL; </para>
61  </refsect1>
62
63  <refsect1>
64    &return-value;
65
66    <variablelist>
67      <varlistentry>
68	<term><errorcode>EINVAL</errorcode></term>
69	<listitem>
70	  <para>This ioctl is not supported, or the
71<constant>VIDIOC_S_DV_PRESET</constant>,<constant>VIDIOC_S_DV_PRESET</constant> parameter was unsuitable.</para>
72	</listitem>
73      </varlistentry>
74      <varlistentry>
75	<term><errorcode>EBUSY</errorcode></term>
76	<listitem>
77	  <para>The device is busy and therefore can not change the preset.</para>
78	</listitem>
79      </varlistentry>
80    </variablelist>
81
82    <table pgwide="1" frame="none" id="v4l2-dv-preset">
83      <title>struct <structname>v4l2_dv_preset</structname></title>
84      <tgroup cols="3">
85	&cs-str;
86	<tbody valign="top">
87	  <row>
88	    <entry>__u32</entry>
89	    <entry><structfield>preset</structfield></entry>
90	    <entry>Preset value to represent the digital video timings</entry>
91	  </row>
92	  <row>
93	    <entry>__u32</entry>
94	    <entry><structfield>reserved[4]</structfield></entry>
95	    <entry>Reserved fields for future use</entry>
96	  </row>
97	</tbody>
98      </tgroup>
99    </table>
100  </refsect1>
101  <refsect1>
102    &return-value;
103  </refsect1>
104</refentry>
105