1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>usb_reset_configuration</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-set-interface.html" title="usb_set_interface"><link rel="next" href="API-usb-driver-set-configuration.html" title="usb_driver_set_configuration"></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_reset_configuration</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-usb-set-interface.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-driver-set-configuration.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-usb-reset-configuration"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>usb_reset_configuration &#8212; 
2     lightweight device reset
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">int <b class="fsfunc">usb_reset_configuration </b>(</code></td><td>struct usb_device * <var class="pdparam">dev</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1116280172"></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     the device whose configuration is being reset
5    </p></dd></dl></div></div><div class="refsect1"><a name="idp1116281764"></a><h2>Description</h2><p>
6   This issues a standard SET_CONFIGURATION request to the device using
7   the current configuration.  The effect is to reset most USB-related
8   state in the device, including interface altsettings (reset to zero),
9   endpoint halts (cleared), and endpoint state (only for bulk and interrupt
10   endpoints).  Other usbcore state is unchanged, including bindings of
11   usb device drivers to interfaces.
12   </p><p>
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14   Because this affects multiple interfaces, avoid using this with composite
15   (multi-interface) devices.  Instead, the driver for each interface may
16   use <code class="function">usb_set_interface</code> on the interfaces it claims.  Be careful though;
17   some devices don't support the SET_INTERFACE request, and others won't
18   reset all the interface state (notably endpoint state).  Resetting the whole
19   configuration would affect other drivers' interfaces.
20   </p><p>
21
22   The caller must own the device lock.
23</p></div><div class="refsect1"><a name="idp1116283812"></a><h2>Return</h2><p>
24   Zero on success, else a negative error code.
25</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-set-interface.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-driver-set-configuration.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">usb_set_interface</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_driver_set_configuration</span></td></tr></table></div></body></html>
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