<?xml version="1.0" encoding="ANSI_X3.4-1968" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968" /><title>ioctl VIDIOC_S_HW_FREQ_SEEK</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /><link rel="home" href="index.html" title="LINUX MEDIA INFRASTRUCTURE API" /><link rel="up" href="apa.html" title="Appendix A. Function Reference" /><link rel="prev" href="re59.html" title="ioctl VIDIOC_REQBUFS" /><link rel="next" href="re61.html" title="ioctl VIDIOC_STREAMON, VIDIOC_STREAMOFF" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">ioctl VIDIOC_S_HW_FREQ_SEEK</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="re59.html">Prev</a> </td><th width="60%" align="center">Appendix A. Function Reference</th><td width="20%" align="right"> <a accesskey="n" href="re61.html">Next</a></td></tr></table><hr /></div><div class="refentry" title="ioctl VIDIOC_S_HW_FREQ_SEEK"><a id="vidioc-s-hw-freq-seek"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>VIDIOC_S_HW_FREQ_SEEK — Perform a hardware frequency seek</p></div><div class="refsynopsisdiv" title="Synopsis"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" class="funcprototype-table"><tr><td><code class="funcdef">int <b class="fsfunc">ioctl</b>(</code></td><td>int <var class="pdparam">fd</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">request</var>, </td></tr><tr><td> </td><td>struct v4l2_hw_freq_seek *<var class="pdparam">argp</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1" title="Arguments"><a id="id2927394"></a><h2>Arguments</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>fd</code></em></span></dt><dd><p>File descriptor returned by <a class="link" href="re64.html" title="V4L2 open()"><code class="function">open()</code></a>.</p></dd><dt><span class="term"><em class="parameter"><code>request</code></em></span></dt><dd><p>VIDIOC_S_HW_FREQ_SEEK</p></dd><dt><span class="term"><em class="parameter"><code>argp</code></em></span></dt><dd><p></p></dd></dl></div></div><div class="refsect1" title="Description"><a id="id2927462"></a><h2>Description</h2><p>Start a hardware frequency seek from the current frequency. To do this applications initialize the <em class="structfield"><code>tuner</code></em>, <em class="structfield"><code>type</code></em>, <em class="structfield"><code>seek_upward</code></em> and <em class="structfield"><code>wrap_around</code></em> fields, and zero out the <em class="structfield"><code>reserved</code></em> array of a struct <a class="link" href="re60.html#v4l2-hw-freq-seek" title="Table A.73. struct v4l2_hw_freq_seek">v4l2_hw_freq_seek</a> and call the <code class="constant">VIDIOC_S_HW_FREQ_SEEK</code> ioctl with a pointer to this structure.</p><p>This ioctl is supported if the <code class="constant">V4L2_CAP_HW_FREQ_SEEK</code> capability is set.</p><div class="table"><a id="v4l2-hw-freq-seek"></a><p class="title"><b>Table A.73. struct <span class="structname">v4l2_hw_freq_seek</span></b></p><div class="table-contents"><table summary="struct v4l2_hw_freq_seek" width="100%" border="0"><colgroup><col /><col /><col /></colgroup><tbody valign="top"><tr><td valign="top">__u32</td><td valign="top"><em class="structfield"><code>tuner</code></em></td><td valign="top">The tuner index number. This is the same value as in the struct <a class="link" href="re31.html#v4l2-input" title="Table A.22. struct v4l2_input">v4l2_input</a> <em class="structfield"><code>tuner</code></em> field and the struct <a class="link" href="re51.html#v4l2-tuner" title="Table A.60. struct v4l2_tuner">v4l2_tuner</a> <em class="structfield"><code>index</code></em> field.</td></tr><tr><td valign="top">enum <a class="link" href="re51.html#v4l2-tuner-type" title="Table A.61. enum v4l2_tuner_type">v4l2_tuner_type</a></td><td valign="top"><em class="structfield"><code>type</code></em></td><td valign="top">The tuner type. This is the same value as in the struct <a class="link" href="re51.html#v4l2-tuner" title="Table A.60. struct v4l2_tuner">v4l2_tuner</a> <em class="structfield"><code>type</code></em> field.</td></tr><tr><td valign="top">__u32</td><td valign="top"><em class="structfield"><code>seek_upward</code></em></td><td valign="top">If non-zero, seek upward from the current frequency, else seek downward.</td></tr><tr><td valign="top">__u32</td><td valign="top"><em class="structfield"><code>wrap_around</code></em></td><td valign="top">If non-zero, wrap around when at the end of the frequency range, else stop seeking.</td></tr><tr><td valign="top">__u32</td><td valign="top"><em class="structfield"><code>reserved</code></em>[8]</td><td valign="top">Reserved for future extensions. Drivers and applications must set the array to zero.</td></tr></tbody></table></div></div><br class="table-break" /></div><div class="refsect1" title="Return Value"><a id="id2927686"></a><h2>Return Value</h2><p>On success <span class="returnvalue">0</span> is returned, on error <span class="returnvalue">-1</span> and the <code class="varname">errno</code> variable is set appropriately:</p><div class="variablelist"><dl><dt><span class="term"><span class="errorcode">EINVAL</span></span></dt><dd><p>The <em class="structfield"><code>tuner</code></em> index is out of bounds or the value in the <em class="structfield"><code>type</code></em> field is wrong.</p></dd><dt><span class="term"><span class="errorcode">EAGAIN</span></span></dt><dd><p>The ioctl timed-out. Try again.</p></dd></dl></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="re59.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="apa.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="re61.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ioctl VIDIOC_REQBUFS </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> ioctl VIDIOC_STREAMON, VIDIOC_STREAMOFF</td></tr></table></div></body></html>
