glfs/multimedia/libdriv/alsa/driver/alsa-driver-config.xml

<sect2>
<title>Configuring alsa-driver</title>

<sect3><title>Config files</title>

<para><userinput>/etc/modules.conf</userinput> and 
<userinput>/etc/asound.state</userinput></para>

</sect3>

<sect3><title>Configuration Information</title>

<para>To configure the alsa drivers, you need to add some lines to
<filename>/etc/modules.conf</filename>:</para>

<para><screen><userinput>cat &gt;&gt; /etc/modules.conf &lt;&lt; "EOF"</userinput>
alias char-major-14 soundcore
alias char-major-116 snd

alias snd-card-0 snd-&lt;soundcard-name&gt;

alias sound-slot-0 snd-card-0

alias sound-service-0-0 snd-mixer-oss
alias sound-service-0-1 snd-seq-oss
alias sound-service-0-3 snd-pcm-oss
alias sound-service-0-8 snd-seq-midi
<userinput>EOF</userinput></screen></para>

<para>&lt;soundcard-name&gt; needs to be replaced with the driver relevant
to your soundcard.  If you have more than one soundcard, you can add
additional sections by repeating the above but changing the first 0 to 1 and
so on.</para>

<para>After editing <filename>/etc/modules.conf</filename> you need to run
<filename>depmod</filename>.  If the drivers you have compiled are for the
version of the kernel you are currently running, simply run
<screen><userinput>depmod</userinput></screen>  If you are compiling 
drivers for a different kernel version to that which you are running, you 
will need to use a line along the lines of:
<screen><userinput>depmod -a 2.4.19 -F /boot/System.map-2.4.19</userinput></screen></para>

<para>Probably the easiest way to store mixer levels is to set and retrieve
them using a bootscript.  It is possible to do this with a
<userinput>post-install</userinput> line in
<filename>/etc/modules.conf</filename> but this is left as an exercise for
those readers who wish to do this.</para>

<para>The alsa-drivers package installs a script as
<filename>/etc/rc.d/init.d/alsasound</filename>.  While it is possible to use
this script, it contains a lot of extraneous detail which isn't needed on an
LFS system and so we create our own script
<filename>/etc/rc.d/init.d/alsa</filename>.</para>

<para>To create the alsa script, do the following:</para>

<para><screen><userinput>cat &gt; /etc/rc.d/init.d/alsa &lt;&lt; "EOF"</userinput>
#!/bin/sh
# Begin $rc_base/init.d/alsa

# Based on sysklogd script from LFS-3.1 and earlier.
# Rewritten by Gerard Beekmans  - gerard@linuxfromscratch.org
# ALSA specific parts by Mark Hymers - markh@linuxfromscratch.org
# Stores mixer settings in the default location: /etc/asound.state

source /etc/sysconfig/rc
source $rc_functions

case "$1" in
    start)
        echo -n "Starting alsa...    Restoring volumes..."
        loadproc /usr/sbin/alsactl restore
        #echo -n "                    Loading MIDI font..."
        #loadproc sfxload /path/to/soundfont
        ;;

    stop)
        echo -n "Stopping alsa...    Saving volumes......"
        loadproc /usr/sbin/alsactl store
        #echo -n "            Removing MIDI font.........."
        #loadproc sfxload -i
        ;;

    restart)
        $0 stop
        /usr/bin/sleep 1
        $0 start
        ;;

    *)
        echo "Usage: $0 {start|stop|restart}"
        exit 1
        ;;

esac

# End $rc_base/init.d/alsa
<userinput>EOF
chmod 755 /etc/rc.d/init.d/alsa</userinput></screen></para>

<para>You can then create the appropriate symlinks:
<screen><userinput>cd /etc/rc.d/init.d &amp;&amp;
ln -sf ../init.d/alsa ../rc0.d/K35alsa &amp;&amp;
ln -sf ../init.d/alsa ../rc1.d/K35alsa &amp;&amp;
ln -sf ../init.d/alsa ../rc2.d/S40alsa &amp;&amp;
ln -sf ../init.d/alsa ../rc3.d/S40alsa &amp;&amp;
ln -sf ../init.d/alsa ../rc4.d/S40alsa &amp;&amp;
ln -sf ../init.d/alsa ../rc5.d/S40alsa &amp;&amp;
ln -sf ../init.d/alsa ../rc6.d/K35alsa</userinput></screen></para>

<para>Note that all channels of your soundcard are muted by default. You can
use the <filename>alsamixer</filename> program from alsa-utils (or any other
OSS mixer) to change this.</para>

<para>Also, the first time the above script is run, it will complain that
there is no state in <filename>/etc/asound.state</filename>.  You can
prevent this by running the following commands after installing alsa-utils:
<screen><userinput>touch /etc/asound.state &amp;&amp;
alsactl store</userinput></screen></para>

<para>A final note is that the lines loading <filename>sfxload</filename>
are commented out.  They are there as an example of other things you may
wish to do in the startup script.  <filename>sfxload</filename> is a
seperate package of interest to SoundBlaster AWE and Live! users.  It is
designed for loading "sound-fonts" (which are used for MIDI output).  You
may wish to delete these lines and add your own or, if you have the relevant
soundcard, install <filename>sfxload</filename> and uncomment them.</para>

</sect3>

</sect2>