Mauro Carvalho Chehab | 8e080c2 | 2009-09-13 22:16:04 -0300 | [diff] [blame] | 1 | <refentry id="vidioc-s-hw-freq-seek"> |
| 2 | <refmeta> |
| 3 | <refentrytitle>ioctl VIDIOC_S_HW_FREQ_SEEK</refentrytitle> |
| 4 | &manvol; |
| 5 | </refmeta> |
| 6 | |
| 7 | <refnamediv> |
| 8 | <refname>VIDIOC_S_HW_FREQ_SEEK</refname> |
| 9 | <refpurpose>Perform a hardware frequency seek</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 v4l2_hw_freq_seek |
| 19 | *<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_S_HW_FREQ_SEEK</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>Start a hardware frequency seek from the current frequency. |
| 53 | To do this applications initialize the <structfield>tuner</structfield>, |
| 54 | <structfield>type</structfield>, <structfield>seek_upward</structfield> and |
| 55 | <structfield>wrap_around</structfield> fields, and zero out the |
| 56 | <structfield>reserved</structfield> array of a &v4l2-hw-freq-seek; and |
| 57 | call the <constant>VIDIOC_S_HW_FREQ_SEEK</constant> ioctl with a pointer |
| 58 | to this structure.</para> |
| 59 | |
| 60 | <para>This ioctl is supported if the <constant>V4L2_CAP_HW_FREQ_SEEK</constant> capability is set.</para> |
| 61 | |
| 62 | <table pgwide="1" frame="none" id="v4l2-hw-freq-seek"> |
| 63 | <title>struct <structname>v4l2_hw_freq_seek</structname></title> |
| 64 | <tgroup cols="3"> |
| 65 | &cs-str; |
| 66 | <tbody valign="top"> |
| 67 | <row> |
| 68 | <entry>__u32</entry> |
| 69 | <entry><structfield>tuner</structfield></entry> |
| 70 | <entry>The tuner index number. This is the |
| 71 | same value as in the &v4l2-input; <structfield>tuner</structfield> |
| 72 | field and the &v4l2-tuner; <structfield>index</structfield> field.</entry> |
| 73 | </row> |
| 74 | <row> |
| 75 | <entry>&v4l2-tuner-type;</entry> |
| 76 | <entry><structfield>type</structfield></entry> |
| 77 | <entry>The tuner type. This is the same value as in the |
| 78 | &v4l2-tuner; <structfield>type</structfield> field.</entry> |
| 79 | </row> |
| 80 | <row> |
| 81 | <entry>__u32</entry> |
| 82 | <entry><structfield>seek_upward</structfield></entry> |
| 83 | <entry>If non-zero, seek upward from the current frequency, else seek downward.</entry> |
| 84 | </row> |
| 85 | <row> |
| 86 | <entry>__u32</entry> |
| 87 | <entry><structfield>wrap_around</structfield></entry> |
| 88 | <entry>If non-zero, wrap around when at the end of the frequency range, else stop seeking.</entry> |
| 89 | </row> |
| 90 | <row> |
| 91 | <entry>__u32</entry> |
| 92 | <entry><structfield>reserved</structfield>[8]</entry> |
| 93 | <entry>Reserved for future extensions. Drivers and |
| 94 | applications must set the array to zero.</entry> |
| 95 | </row> |
| 96 | </tbody> |
| 97 | </tgroup> |
| 98 | </table> |
| 99 | </refsect1> |
| 100 | |
| 101 | <refsect1> |
| 102 | &return-value; |
| 103 | |
| 104 | <variablelist> |
| 105 | <varlistentry> |
| 106 | <term><errorcode>EINVAL</errorcode></term> |
| 107 | <listitem> |
| 108 | <para>The <structfield>tuner</structfield> index is out of |
| 109 | bounds or the value in the <structfield>type</structfield> field is |
| 110 | wrong.</para> |
| 111 | </listitem> |
| 112 | </varlistentry> |
| 113 | <varlistentry> |
| 114 | <term><errorcode>EAGAIN</errorcode></term> |
| 115 | <listitem> |
| 116 | <para>The ioctl timed-out. Try again.</para> |
| 117 | </listitem> |
| 118 | </varlistentry> |
| 119 | </variablelist> |
| 120 | </refsect1> |
| 121 | </refentry> |
| 122 | |
| 123 | <!-- |
| 124 | Local Variables: |
| 125 | mode: sgml |
| 126 | sgml-parent-document: "v4l2.sgml" |
| 127 | indent-tabs-mode: nil |
| 128 | End: |
| 129 | --> |