1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>uart_get_baud_rate</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="uart16x50.html" title="Chapter&#160;6.&#160;16x50 UART Driver"><link rel="prev" href="API-uart-update-timeout.html" title="uart_update_timeout"><link rel="next" href="API-uart-get-divisor.html" title="uart_get_divisor"></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">uart_get_baud_rate</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-uart-update-timeout.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;6.&#160;16x50 UART Driver</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-uart-get-divisor.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-uart-get-baud-rate"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>uart_get_baud_rate &#8212; 
2     return baud rate for a particular port
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">unsigned int <b class="fsfunc">uart_get_baud_rate </b>(</code></td><td>struct uart_port * <var class="pdparam">port</var>, </td></tr><tr><td>&#160;</td><td>struct ktermios * <var class="pdparam">termios</var>, </td></tr><tr><td>&#160;</td><td>struct ktermios * <var class="pdparam">old</var>, </td></tr><tr><td>&#160;</td><td>unsigned int <var class="pdparam">min</var>, </td></tr><tr><td>&#160;</td><td>unsigned int <var class="pdparam">max</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1113776372"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>port</code></em></span></dt><dd><p>
4     uart_port structure describing the port in question.
5    </p></dd><dt><span class="term"><em class="parameter"><code>termios</code></em></span></dt><dd><p>
6     desired termios settings.
7    </p></dd><dt><span class="term"><em class="parameter"><code>old</code></em></span></dt><dd><p>
8     old termios (or NULL)
9    </p></dd><dt><span class="term"><em class="parameter"><code>min</code></em></span></dt><dd><p>
10     minimum acceptable baud rate
11    </p></dd><dt><span class="term"><em class="parameter"><code>max</code></em></span></dt><dd><p>
12     maximum acceptable baud rate
13    </p></dd></dl></div></div><div class="refsect1"><a name="idp1113782092"></a><h2>Description</h2><p>
14   Decode the termios structure into a numeric baud rate,
15   taking account of the magic 38400 baud rate (with spd_*
16   flags), and mapping the <code class="constant">B0</code> rate to 9600 baud.
17   </p><p>
18
19   If the new baud rate is invalid, try the old termios setting.
20   If it's still invalid, we try 9600 baud.
21   </p><p>
22
23   Update the <em class="parameter"><code>termios</code></em> structure to reflect the baud rate
24   we're actually going to be using. Don't do this for the case
25   where B0 is requested (<span class="quote">&#8220;<span class="quote">hang up</span>&#8221;</span>).
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-uart-update-timeout.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="uart16x50.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-uart-get-divisor.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">uart_update_timeout</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">uart_get_divisor</span></td></tr></table></div></body></html>
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