1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>snd_ctl_make_virtual_master</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The ALSA Driver API"><link rel="up" href="ch03s03.html" title="Virtual Master Control API"><link rel="prev" href="ch03s03.html" title="Virtual Master Control API"><link rel="next" href="API-snd-ctl-add-vmaster-hook.html" title="snd_ctl_add_vmaster_hook"></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">snd_ctl_make_virtual_master</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch03s03.html">Prev</a>&#160;</td><th width="60%" align="center">Virtual Master Control API</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-snd-ctl-add-vmaster-hook.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-snd-ctl-make-virtual-master"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>snd_ctl_make_virtual_master &#8212; 
2  Create a virtual master control
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">struct snd_kcontrol * <b class="fsfunc">snd_ctl_make_virtual_master </b>(</code></td><td>char * <var class="pdparam">name</var>, </td></tr><tr><td>&#160;</td><td>const unsigned int * <var class="pdparam">tlv</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1094816572"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>name</code></em></span></dt><dd><p>
4     name string of the control element to create
5    </p></dd><dt><span class="term"><em class="parameter"><code>tlv</code></em></span></dt><dd><p>
6     optional TLV int array for dB information
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1094819244"></a><h2>Description</h2><p>
8   Creates a virtual master control with the given name string.
9   </p><p>
10
11   After creating a vmaster element, you can add the slave controls
12   via <code class="function">snd_ctl_add_slave</code> or <code class="function">snd_ctl_add_slave_uncached</code>.
13   </p><p>
14
15   The optional argument <em class="parameter"><code>tlv</code></em> can be used to specify the TLV information
16   for dB scale of the master control.  It should be a single element
17   with #SNDRV_CTL_TLVT_DB_SCALE, #SNDRV_CTL_TLV_DB_MINMAX or
18   #SNDRV_CTL_TLVT_DB_MINMAX_MUTE type, and should be the max 0dB.
19</p></div><div class="refsect1"><a name="idp1094821612"></a><h2>Return</h2><p>
20   The created control element, or <code class="constant">NULL</code> for errors (ENOMEM).
21</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch03s03.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="ch03s03.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-snd-ctl-add-vmaster-hook.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Virtual Master Control API&#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">snd_ctl_add_vmaster_hook</span></td></tr></table></div></body></html>
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