1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>usb_free_coherent</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The Linux-USB Host Side API"><link rel="up" href="usbcore.html" title="Chapter&#160;5.&#160;USB Core APIs"><link rel="prev" href="API-usb-alloc-coherent.html" title="usb_alloc_coherent"><link rel="next" href="API-usb-buffer-map.html" title="usb_buffer_map"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">usb_free_coherent</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-usb-alloc-coherent.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;5.&#160;USB Core APIs</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-usb-buffer-map.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-usb-free-coherent"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>usb_free_coherent &#8212; 
2     free memory allocated with <code class="function">usb_alloc_coherent</code>
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <b class="fsfunc">usb_free_coherent </b>(</code></td><td>struct usb_device * <var class="pdparam">dev</var>, </td></tr><tr><td>&#160;</td><td>size_t <var class="pdparam">size</var>, </td></tr><tr><td>&#160;</td><td>void * <var class="pdparam">addr</var>, </td></tr><tr><td>&#160;</td><td>dma_addr_t <var class="pdparam">dma</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1116579572"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>dev</code></em></span></dt><dd><p>
4     device the buffer was used with
5    </p></dd><dt><span class="term"><em class="parameter"><code>size</code></em></span></dt><dd><p>
6     requested buffer size
7    </p></dd><dt><span class="term"><em class="parameter"><code>addr</code></em></span></dt><dd><p>
8     CPU address of buffer
9    </p></dd><dt><span class="term"><em class="parameter"><code>dma</code></em></span></dt><dd><p>
10     DMA address of buffer
11    </p></dd></dl></div></div><div class="refsect1"><a name="idp1116584236"></a><h2>Description</h2><p>
12   This reclaims an I/O buffer, letting it be reused.  The memory must have
13   been allocated using <code class="function">usb_alloc_coherent</code>, and the parameters must match
14   those provided in that allocation request.
15</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-usb-alloc-coherent.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="usbcore.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-usb-buffer-map.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">usb_alloc_coherent</span>&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">usb_buffer_map</span></td></tr></table></div></body></html>
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