1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>subsys_virtual_register</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux Device Drivers"><link rel="up" href="ch02s02.html" title="Device Drivers Base"><link rel="prev" href="API-subsys-system-register.html" title="subsys_system_register"><link rel="next" href="ch02s03.html" title="Device Drivers DMA Management"></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">subsys_virtual_register</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-subsys-system-register.html">Prev</a>&#160;</td><th width="60%" align="center">Device Drivers Base</th><td width="20%" align="right">&#160;<a accesskey="n" href="ch02s03.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-subsys-virtual-register"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>subsys_virtual_register &#8212; 
2     register a subsystem at /sys/devices/virtual/
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">subsys_virtual_register </b>(</code></td><td>struct bus_type * <var class="pdparam">subsys</var>, </td></tr><tr><td>&#160;</td><td>const struct attribute_group ** <var class="pdparam">groups</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1110132860"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>subsys</code></em></span></dt><dd><p>
4     virtual subsystem
5    </p></dd><dt><span class="term"><em class="parameter"><code>groups</code></em></span></dt><dd><p>
6     default attributes for the root device
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1110135516"></a><h2>Description</h2><p>
8   All 'virtual' subsystems have a /sys/devices/system/&lt;name&gt; root device
9   with the name of the subystem.  The root device can carry subsystem-wide
10   attributes.  All registered devices are below this single root device.
11   There's no restriction on device naming.  This is for kernel software
12   constructs which need sysfs interface.
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