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<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968" /><title>class_find_device</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /><link rel="home" href="index.html" title="Linux Device Drivers" /><link rel="up" href="ch02.html#id3048322" title="Device Drivers Base" /><link rel="prev" href="re205.html" title="class_for_each_device" /><link rel="next" href="re207.html" title="class_compat_register" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span>class_find_device</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="re205.html">Prev</a> </td><th width="60%" align="center">Device Drivers Base</th><td width="20%" align="right"> <a accesskey="n" href="re207.html">Next</a></td></tr></table><hr /></div><div class="refentry" title="class_find_device"><a id="API-class-find-device"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>class_find_device —
device iterator for locating a particular device
</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">struct device * <b class="fsfunc">class_find_device </b>(</code></td><td>struct class * <var class="pdparam">class</var>, </td></tr><tr><td> </td><td>struct device * <var class="pdparam">start</var>, </td></tr><tr><td> </td><td>void * <var class="pdparam">data</var>, </td></tr><tr><td> </td><td>int (*<var class="pdparam">match</var>)
<code>(</code>struct device *, void *<code>)</code><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1" title="Arguments"><a id="id3054686"></a><h2>Arguments</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>class</code></em></span></dt><dd><p>
the class we're iterating
</p></dd><dt><span class="term"><em class="parameter"><code>start</code></em></span></dt><dd><p>
Device to begin with
</p></dd><dt><span class="term"><em class="parameter"><code>data</code></em></span></dt><dd><p>
data for the match function
</p></dd><dt><span class="term"><em class="parameter"><code>match</code></em></span></dt><dd><p>
function to check device
</p></dd></dl></div></div><div class="refsect1" title="Description"><a id="id3054765"></a><h2>Description</h2><p>
This is similar to the <code class="function">class_for_each_dev</code> function above, but it
returns a reference to a device that is 'found' for later use, as
determined by the <em class="parameter"><code>match</code></em> callback.
</p><p>
The callback should return 0 if the device doesn't match and non-zero
if it does. If the callback returns non-zero, this function will
return to the caller and not iterate over any more devices.
</p><p>
Note, you will need to drop the reference with <code class="function">put_device</code> after use.
</p><p>
<em class="parameter"><code>fn</code></em> is allowed to do anything including calling back into class
code. There's no locking restriction.
</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="re205.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02.html#id3048322">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="re207.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span>class_for_each_device</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span>class_compat_register</span></td></tr></table></div></body></html>
