1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>blk_pm_runtime_init</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The Linux Kernel API"><link rel="up" href="blkdev.html" title="Chapter&#160;14.&#160;Block Devices"><link rel="prev" href="API-blk-start-plug.html" title="blk_start_plug"><link rel="next" href="API-blk-pre-runtime-suspend.html" title="blk_pre_runtime_suspend"></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">blk_pm_runtime_init</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-blk-start-plug.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;14.&#160;Block Devices</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-blk-pre-runtime-suspend.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-blk-pm-runtime-init"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>blk_pm_runtime_init &#8212; 
2     Block layer runtime PM initialization routine
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">blk_pm_runtime_init </b>(</code></td><td>struct request_queue * <var class="pdparam">q</var>, </td></tr><tr><td>&#160;</td><td>struct device * <var class="pdparam">dev</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1128153772"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>q</code></em></span></dt><dd><p>
4     the queue of the device
5    </p></dd><dt><span class="term"><em class="parameter"><code>dev</code></em></span></dt><dd><p>
6     the device the queue belongs to
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1128156388"></a><h2>Description</h2><p>
8   Initialize runtime-PM-related fields for <em class="parameter"><code>q</code></em> and start auto suspend for
9   <em class="parameter"><code>dev</code></em>. Drivers that want to take advantage of request-based runtime PM
10   should call this function after <em class="parameter"><code>dev</code></em> has been initialized, and its
11   request queue <em class="parameter"><code>q</code></em> has been allocated, and runtime PM for it can not happen
12   yet(either due to disabled/forbidden or its usage_count &gt; 0). In most
13   cases, driver should call this function before any I/O has taken place.
14   </p><p>
15
16   This function takes care of setting up using auto suspend for the device,
17   the autosuspend delay is set to -1 to make runtime suspend impossible
18   until an updated value is either set by user or by driver. Drivers do
19   not need to touch other autosuspend settings.
20   </p><p>
21
22   The block layer runtime PM is request based, so only works for drivers
23   that use request as their IO unit instead of those directly use bio's.
24</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-blk-start-plug.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="blkdev.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-blk-pre-runtime-suspend.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">blk_start_plug</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">blk_pre_runtime_suspend</span></td></tr></table></div></body></html>
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