Based on kernel version 3.0.4. Page generated on 2011-10-03 22:07 EST.
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>, 55 <structfield>spacing</structfield> and 56 <structfield>wrap_around</structfield> fields, and zero out the 57 <structfield>reserved</structfield> array of a &v4l2-hw-freq-seek; and 58 call the <constant>VIDIOC_S_HW_FREQ_SEEK</constant> ioctl with a pointer 59 to this structure.</para> 60 61 <para>This ioctl is supported if the <constant>V4L2_CAP_HW_FREQ_SEEK</constant> capability is set.</para> 62 63 <table pgwide="1" frame="none" id="v4l2-hw-freq-seek"> 64 <title>struct <structname>v4l2_hw_freq_seek</structname></title> 65 <tgroup cols="3"> 66 &cs-str; 67 <tbody valign="top"> 68 <row> 69 <entry>__u32</entry> 70 <entry><structfield>tuner</structfield></entry> 71 <entry>The tuner index number. This is the 72 same value as in the &v4l2-input; <structfield>tuner</structfield> 73 field and the &v4l2-tuner; <structfield>index</structfield> field.</entry> 74 </row> 75 <row> 76 <entry>&v4l2-tuner-type;</entry> 77 <entry><structfield>type</structfield></entry> 78 <entry>The tuner type. This is the same value as in the 79 &v4l2-tuner; <structfield>type</structfield> field.</entry> 80 </row> 81 <row> 82 <entry>__u32</entry> 83 <entry><structfield>seek_upward</structfield></entry> 84 <entry>If non-zero, seek upward from the current frequency, else seek downward.</entry> 85 </row> 86 <row> 87 <entry>__u32</entry> 88 <entry><structfield>wrap_around</structfield></entry> 89 <entry>If non-zero, wrap around when at the end of the frequency range, else stop seeking.</entry> 90 </row> 91 <row> 92 <entry>__u32</entry> 93 <entry><structfield>spacing</structfield></entry> 94 <entry>If non-zero, defines the hardware seek resolution in Hz. The driver selects the nearest value that is supported by the device. If spacing is zero a reasonable default value is used.</entry> 95 </row> 96 <row> 97 <entry>__u32</entry> 98 <entry><structfield>reserved</structfield>[7]</entry> 99 <entry>Reserved for future extensions. Drivers and 100 applications must set the array to zero.</entry> 101 </row> 102 </tbody> 103 </tgroup> 104 </table> 105 </refsect1> 106 107 <refsect1> 108 &return-value; 109 110 <variablelist> 111 <varlistentry> 112 <term><errorcode>EINVAL</errorcode></term> 113 <listitem> 114 <para>The <structfield>tuner</structfield> index is out of 115 bounds or the value in the <structfield>type</structfield> field is 116 wrong.</para> 117 </listitem> 118 </varlistentry> 119 <varlistentry> 120 <term><errorcode>EAGAIN</errorcode></term> 121 <listitem> 122 <para>The ioctl timed-out. Try again.</para> 123 </listitem> 124 </varlistentry> 125 </variablelist> 126 </refsect1> 127 </refentry> 128 129 <!-- 130 Local Variables: 131 mode: sgml 132 sgml-parent-document: "v4l2.sgml" 133 indent-tabs-mode: nil 134 End: 135 -->
