1<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>clk_round_rate</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="clk.html" title="Chapter 17. Clock Framework"><link rel="prev" href="API-devm-clk-put.html" title="devm_clk_put"><link rel="next" href="API-clk-set-rate.html" title="clk_set_rate"></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">clk_round_rate</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-devm-clk-put.html">Prev</a> </td><th width="60%" align="center">Chapter 17. Clock Framework</th><td width="20%" align="right"> <a accesskey="n" href="API-clk-set-rate.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-clk-round-rate"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>clk_round_rate — 
2     adjust a rate to the exact rate a clock can provide
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">long <b class="fsfunc">clk_round_rate </b>(</code></td><td>struct clk * <var class="pdparam">clk</var>, </td></tr><tr><td> </td><td>unsigned long <var class="pdparam">rate</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="id-1.19.23.5"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>clk</code></em></span></dt><dd><p>
4     clock source
5    </p></dd><dt><span class="term"><em class="parameter"><code>rate</code></em></span></dt><dd><p>
6     desired clock rate in Hz
7    </p></dd></dl></div></div><div class="refsect1"><a name="id-1.19.23.6"></a><h2>Description</h2><p>
8   This answers the question <span class="quote">“<span class="quote">if I were to pass <em class="parameter"><code>rate</code></em> to <code class="function"><a class="link" href="API-clk-set-rate.html" title="clk_set_rate">clk_set_rate</a></code>,
9   what clock rate would I end up with?</span>”</span> without changing the hardware
10   in any way.  In other words:
11   </p><p>
12
13   rate = clk_round_rate(clk, r);
14</p></div><div class="refsect1"><a name="id-1.19.23.7"></a><h2>and</h2><p>
15   </p><p>
16
17   clk_set_rate(clk, r);
18   rate = clk_get_rate(clk);
19   </p><p>
20
21   are equivalent except the former does not modify the clock hardware
22   in any way.
23   </p><p>
24
25   Returns rounded clock rate in Hz, or negative errno.
26</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-devm-clk-put.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="clk.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="API-clk-set-rate.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">devm_clk_put</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span class="phrase">clk_set_rate</span></td></tr></table></div></body></html>
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