1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>reciprocal_scale</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="ch01s09.html" title="Kernel utility functions"><link rel="prev" href="API-might-sleep.html" title="might_sleep"><link rel="next" href="API-kstrtoul.html" title="kstrtoul"></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">reciprocal_scale</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-might-sleep.html">Prev</a>&#160;</td><th width="60%" align="center">Kernel utility functions</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-kstrtoul.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-reciprocal-scale"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>reciprocal_scale &#8212; 
2     "scale" a value into range [0, ep_ro)
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">u32 <b class="fsfunc">reciprocal_scale </b>(</code></td><td>u32 <var class="pdparam">val</var>, </td></tr><tr><td>&#160;</td><td>u32 <var class="pdparam">ep_ro</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1108321148"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>val</code></em></span></dt><dd><p>
4     value
5    </p></dd><dt><span class="term"><em class="parameter"><code>ep_ro</code></em></span></dt><dd><p>
6     right open interval endpoint
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1108323764"></a><h2>Description</h2><p>
8   Perform a <span class="quote">&#8220;<span class="quote">reciprocal multiplication</span>&#8221;</span> in order to <span class="quote">&#8220;<span class="quote">scale</span>&#8221;</span> a value into
9   range [0, ep_ro), where the upper interval endpoint is right-open.
10   This is useful, e.g. for accessing a index of an array containing
11   ep_ro elements, for example. Think of it as sort of modulus, only that
12   the result isn't that of modulo. ;) Note that if initial input is a
13   small value, then result will return 0.
14</p></div><div class="refsect1"><a name="idp1108325188"></a><h2>Return</h2><p>
15   a result based on val in interval [0, ep_ro).
16</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-might-sleep.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="ch01s09.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-kstrtoul.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">might_sleep</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">kstrtoul</span></td></tr></table></div></body></html>
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