doc/en/alsa-guide.xml

<?xml version='1.0' encoding="UTF-8"?>
<!DOCTYPE guide SYSTEM "/dtd/guide.dtd">

<guide link = "/doc/en/alsa-guide.xml">
<title>Gentoo Linux ALSA Guide</title>
<author title="Author"><mail link="zu@pandora.be">
        Vincent Verleye</mail>
</author>
<author title="Author"><mail link="g2boojum@gentoo.org">
        Grant Goodyear</mail>
</author>
<author title="Author"><mail link="agenkin@gentoo.org">
        Arcady Genkin</mail>
</author>
<author title="Editor"><mail link="zhen@gentoo.org">
        John P. Davis</mail>
</author>
<author title="Editor"><mail link="swift@gentoo.org">
    Sven Vermeulen</mail>
</author>

<license/>

<abstract>
This guide will show you how to set up the Advanced Linux Sound Architecture (ALSA) on Gentoo Linux.
In addition to the Gentoo Linux Desktop Configuration Guide, this guide is supposed to give you more information on this subject. </abstract>

<version>1.2</version>
<date>5 June 2003</date>

<chapter>
<title>Introduction</title>
<section>
        <title>What is ALSA?</title>
<body>
<p>
The Advanced Linux Sound Architecture (ALSA) is a project to improve the Linux sound subsystem by rewriting 
large chunks of it. 
It is anticipated that ALSA will make it into Linux kernel 2.6.x (or 3.x.x -- whichever comes first) as it becomes ready.
</p>

<p>
ALSA provides audio and MIDI functionality for Linux.
</p>
 
<p>
Quoted from <uri>http://www.alsa-project.org</uri>, ALSA has the following features:
<ul><li> Efficient support for all types of audio interfaces, from consumer soundcards to professional multichannel audio interfaces.</li>
    <li> Fully modularized sound drivers.</li>
    <li> SMP and thread-safe design.</li>
    <li> User space library (alsa-lib) to simplify application programming and provide higher level functionality.</li>
    <li> Support for the older OSS API, providing binary compatibility for most OSS programs.</li> 
</ul>
There's lots more to ALSA however, like support for Full Duplex playback and recording, multiple soundcard support,
hardware mixing of streams, extensive mixer capabilities (to support advanced features of new soundcards), ...  
</p>
</body>
</section>
<section>
        <title>Why use ALSA?</title>
<body>
<p>
If your soundcard is supported by the Linux kernel sound system or the commercial OSS/4Front sound driver system, 
which can be found in all 2.4.x Linux kernels, you could just aswell build <e>those modules</e> for use with your soundcard. 
If you want this, just read through the <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri>.
</p> 
<p>
However, those OSS/4Front drivers have some limitations -- being commercial is one. 
ALSA is an attempt to go beyond these limitations and to do so in an open source fashion. 
ALSA is a fully GPL and LGPL'ed sound driver system, that provides a professional quality system for recording, playback, 
and MIDI sequencing.
</p> 
</body>
</section>
<section>
        <title>What cards does ALSA support?</title>
<body>
<p>
ALSA tries to support as many (new) cards as possible by providing open-source drivers. 
However, some vendors may provide binary-only packages. 
</p>
<p>To know if your card is supported, you can find a Soundcard Matrix of supported and not-supported cards here: 
<uri>http://www.alsa-project.org/alsa-doc/</uri>.
</p>
</body>
</section>
</chapter>

<chapter>
<title>Installation</title>
<section>
        <title>Kernel modules</title>
<body>
<p>
Since we're still using 2.4.x kernel sources, we'll have to compile kernel modules and ALSA modules separately. People who are using a 2.5.x kernel can do this from within their kernel configuration, since the ALSA modules are included in the kernel sources and should be built there.
</p>
<p>
First we'll make sure that our kernel configuration is ready for use with ALSA. 
All you need in your kernel configuration is having Sound Card Support set to be built as a module (M). 
This will build <c>soundcore.o</c>.
</p>
<p>
<note>
Possibly, this will also work when you built Sound Card Support in the kernel (Y) instead of building it as a module (M).
However, the official ALSA documentation suggests building it as a module, since ALSA will try loading it.
</note>
</p>
<p>If you already have a working kernel configuration, make sure you remove all sound drivers (except for Sound Card Support).
If you wish to do this without having to reboot, you could do like this:
</p>
<pre>
# <c>cd /usr/src/linux</c>
# <c>cp .config ~/</c>
# <c>make mrproper</c>
# <c>cp ~/.config .</c>
# <c>make menuconfig</c>
</pre>
<p>
Now select <e>Sound Card Support</e> as Module (M) and deselect all other sound drivers.
Exit and say Y to save your kernel configuration.
After that, build the modules:
</p>
<pre>
# <c>make dep clean</c>
# <c>make modules modules_install</c>
</pre>
<p>
Before installing your new modules, this last line will delete all your previous modules, 
even the ones from a previous ALSA installation.
</p>
<p>
<impo>
This means, whenever you recompile your kernel later on, you MUST recompile <c>alsa-driver</c>.
</impo>
</p>
<p>
<note>However, there's no need to reinstall <c>nvidia-kernel</c>, the Nvidia drivers are in a separate directory 
in <path>/lib/modules/*/video</path> and won't get deleted by a <c>make modules modules_install</c>
</note>
</p>
</body>
</section>

<section>
        <title>ALSA modules</title>
<body>

<p>
Now it's time to install the ALSA drivers for your soundcard(s). If your soundcard is PCI, you can find out the name
and type of your soundcard by looking at the output of /proc/pci
<pre># <c>grep audio /proc/pci</c></pre>
</p>

<p>
<warn>
If you had a previous sound setup and there are still non-ALSA sound modules loaded, unload them <e>now</e>.
Check with <c>lsmod</c> and use <c>rmmod</c> to unload all sound-related modules on your system.
</warn>
</p>

<p>
We could simply do an <c>emerge alsa-driver</c> now, this would compile and install <e>all</e> ALSA sound drivers.
</p>
<p>
However, to save some time, lookup the <e>Module Name</e> of your soundcard(s) on the 
<uri link="http://www.alsa-project.org/alsa-doc">ALSA Soundcard Matrix</uri> by following the <e>Details</e> link in the <e>Driver and Docs</e> column in the row of the chipset of your soundcard. 
Mine is <c>snd-emu10k1</c>, since I have an SBlive! soundcard, with the <e>EMU10K1</e> chipset.
We'll set ALSA_CARDS environment to the value of the module name before emerging (but without the snd prefix), so emerge will only compile the drivers we need.
</p>

<p>
<pre>
# <c>env ALSA_CARDS='emu10k1' emerge alsa-driver</c> 
</pre>
</p>
<p>
<note>
You can also add this value in <path>/etc/make.conf</path>, so when you have to emerge the alsa-driver later on you can just run <c>emerge alsa-driver</c>.
For example, like this: <c>echo 'ALSA_CARDS="emu10k1"' >> /etc/make.conf</c>
</note>

<note>
When you want to install ALSA drivers for more than one soundcard, you could set ALSA_CARDS to a space-separated list
of drivers; like this: <c>env ALSA_CARDS='emu10k1 intel8x0 ens1370' emerge alsa-driver</c>
</note>

<note>If you want to have OSS compatibility, make sure to emerge <i>alsa-oss</i>, it is the ALSA/OSS compatibility
wrapper. </note>

</p>
<p>
After this, the ALSA modules should be installed on your system.
</p>
</body>
</section>
<section>
        <title>Configuration of ALSA</title>
<body>
<p>
Let's start configuring now to get ALSA working properly.
We'll need to edit some files, to let our system know about the freshly installed ALSA modules.
</p>

<p>
First, install <c>alsa-utils</c> on your system:
</p>

<pre caption = "Emerging alsa-utils">
# <i>emerge alsa-utils</i>
</pre>

<p>
Hereafter, we need to edit <path>/etc/modules.d/alsa</path>.
</p>
<warn>
There is no need to edit <path>/etc/modules.conf</path>. Instead, always edit files in <path>/etc/modules.d</path>.
</warn>
<p>
Check the ALSA portion <e>at the bottom of the file</e>. 
By tweaking this line you can specify the max number of soundcards you have (generally, just one).
</p>
<p>
<pre caption="At the bottom of /etc/modules.d/alsa">
# Set this to the correct number of cards.
<c>options snd cards_limit=1</c>
</pre>
</p>
<p>
Now we'll specify the sounddriver(s) ALSA should use. In the same file, edit like this:
<pre caption="In /etc/modules.d/alsa">
## and then run `update-modules' command.
## Read alsa-driver's INSTALL file in /usr/share/doc for more info.
##
##  ALSA portion
<c>alias snd-card-0 snd-emu10k1</c>
<c>## If you have more than one, add:
## alias snd-card-1 snd-intel8x0
## alias snd-card-2 snd-ens1370</c>
##  OSS/Free portion
## alias sound-slot-0 snd-card-0
## alias sound-slot-1 snd-card-1
##
</pre>
</p>
<p>
<note>
If you have more than one soundcard, adjust the <c>cards_limit</c> value and add more snd-card aliases to the file.
I don't have experience with this, but you can find examples for configurations with two or more soundcards in 
<uri link="http://www.alsa-project.org/alsa-doc/alsa-howto/c1660.htm">Chapter 6</uri>
of the <uri link="http://www.alsa-project.org/alsa-doc/alsa-howto/alsa-howto.html">ALSA Howto</uri>.
</note>
</p>
<p>
Last thing to do in this file, almost at the end, check if these lines are there and uncommented:
<pre caption="Near the end of /etc/modules.d/alsa">
alias /dev/mixer snd-mixer-oss
alias /dev/dsp snd-pcm-oss
alias /dev/midi snd-seq-oss
</pre>
</p>
<p>
Now double-check the file <path>/etc/modules.d/alsa</path> and when you're sure everyting is ok, run <c>update-modules</c>.
<pre>
# <c>update-modules</c>
</pre>
</p>
<note>
Running <c>update-modules</c> here will insert the data from <path>/etc/modules.d/alsa</path> into <path>/etc/modules.conf</path>
</note>
<p>
You should also verify that /etc/devfsd.conf has the alsa devices and permissions correctly registered.
</p>
<pre caption="/etc/devfsd.conf">
# ALSA/OSS stuff
# Comment/change these if you want to change the permissions on
# the audio devices
LOOKUP          snd          MODLOAD ACTION snd
LOOKUP          dsp          MODLOAD
LOOKUP          mixer        MODLOAD
LOOKUP          midi         MODLOAD
REGISTER        sound/.*     PERMISSIONS root.audio 660
REGISTER        snd/.*       PERMISSIONS root.audio 660
</pre>
<note>
Notice that devfsd.conf sets /dev/sound permissions to be root.audio. Thus, for non-root users to use audio they will have to be part of the audio group.
</note>
</body>
</section>
</chapter>
<chapter>
<title>Starting ALSA</title>
<section>
        <title>Adding alsasound to a runlevel</title>
<body>
<p>
First thing to do now, is to make ALSA startup at boottime. Like this:
<pre>
# <c>rc-update add alsasound boot</c>
</pre>
</p>
<p>
<warn>Note that the alsasound script should be added to the "boot" runlevel, not the "default" runlevel.</warn>
</p>
</body>
</section>
<section>
        <title>Running and unmuting</title>
<body>
<p>
Since we're Linux users, we don't want to reboot. So we'll start the alsasound script manually.
</p>
<pre>
# <c>/etc/init.d/alsasound start</c>
</pre>
<p>
ALSA is running now. If everything is ok, you should be able to see the ALSA modules loaded when running <c>lsmod</c>.
However, sound won't work yet, because the channels are still muted. We need <c>amixer</c> for this.
</p>
<pre caption = "Running amixer">
# <i>amixer</i>
</pre>
<p>
<warn>
You shouldn't get this, but <e>if</e> you get an error about "amixer: Mixer attach default error: No such file or directory", you should manually insmod
<c>snd-mixer-oss</c> and <c>snd-pcm-oss</c> once. After that run amixer again.
</warn>
</p>
<pre caption="only if you get an error when running amixer">
# <c>insmod snd-mixer-oss</c>
# <c>insmod snd-pcm-oss</c>
# <c>amixer</c>
</pre>
<p>
If you got this far, now unmute both Master and PCM channels.
</p>
<p>
<pre>
# <c>amixer set Master 100 unmute</c>
# <c>amixer set PCM 100 unmute</c>
# <c>aplay $KDEDIR/share/sounds/pop.wav</c> <codenote>(pop.wav is part of KDE)</codenote>
</pre>
</p>
We check to see if sound is working by using the aplay (alsa play) command. If you hear a pop, then sound is indeed working. 
Then, adjust the volume settings to your liking; the ncurses-based <c>alsamixer</c> is a great way to get them "just so". 
<p>
You may want to emerge <c>alsa-xmms</c> as that will provide ALSA support for XMMS.
</p>
When you reboot your system, the <e>alsasound</e> init script will properly save and restore your volume settings. 
</body>
</section>
</chapter>
<chapter>
<title>Final Notes</title>
<section>
        <title>After kernel-upgrades..</title>
<body>
<p>When you ever rebuild your kernel, or upgrade to another kernel, you'll have to rebuild the ALSA modules.</p>
<p>Although you might have installed <c>alsa-driver</c>, <c>alsa-libs</c> and <c>alsa-utils</c>, only the first will
have to be installed again, since it will put the alsa modules in 
<path>/lib/modules/*/kernel/sound/pci/</path>.</p>
<pre caption="needed after each kernel compile">
# <c>emerge alsa-driver</c>
</pre>
</body>
</section>
<section>
        <title>/etc/modules.autoload</title>
<body>
<p>You won't have to edit this file for use with ALSA. After our <c>rc-update add alsasound boot</c>, our system will
load the correct modules at startup.</p>
<p>It's not necessary to add <c>snd-pcm-oss</c> or <c>snd-mixer-oss</c> in this file. 
Check the <uri link="http://www.djcj.org/LAU/guide/alsbook/faq1.html">this FAQ</uri> for more info.</p>
</body>
</section>
<section>
        <title>More links..</title>
<body>
<p>
You could check these for additional info:
</p>
<p>
<ul>
<li><uri link="http://www.gentoo.org/doc/en/desktop.xml">The Gentoo Linux Desktop Configuration Guide</uri></li>
<li><uri link="http://www.alsa-project.org">ALSA Project Homepage</uri></li>
<li><uri link="http://www.alsa-project.org/documentation.php3">ALSA Users Documentation</uri></li>
<li><uri link="http://www.djcj.org">ALSA Howto's and FAQ's</uri></li>
<li><uri link="http://tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri></li>
<li><uri link="http://linux-sound.org/">Sound and MIDI Software For Linux</uri></li>
</ul>
</p>
</body>
</section>
</chapter>
</guide>
1	zhen	1.3	<?xml version='1.0' encoding="UTF-8"?>
2	drobbins	1.1	<!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
3
4	zhen	1.2	<guide link = "/doc/en/alsa-guide.xml">
5	drobbins	1.1	<title>Gentoo Linux ALSA Guide</title>
6			<author title="Author"><mail link="zu@pandora.be">
7			Vincent Verleye</mail>
8			</author>
9	peesh	1.10	<author title="Author"><mail link="g2boojum@gentoo.org">
10			Grant Goodyear</mail>
11			</author>
12			<author title="Author"><mail link="agenkin@gentoo.org">
13			Arcady Genkin</mail>
14			</author>
15	drobbins	1.1	<author title="Editor"><mail link="zhen@gentoo.org">
16			John P. Davis</mail>
17			</author>
18	swift	1.12	<author title="Editor"><mail link="swift@gentoo.org">
19			Sven Vermeulen</mail>
20			</author>
21	drobbins	1.1
22	swift	1.11	<license/>
23
24	drobbins	1.1	<abstract>
25			This guide will show you how to set up the Advanced Linux Sound Architecture (ALSA) on Gentoo Linux.
26			In addition to the Gentoo Linux Desktop Configuration Guide, this guide is supposed to give you more information on this subject. </abstract>
27
28	zhen	1.7	<version>1.2</version>
29	peesh	1.10	<date>5 June 2003</date>
30	drobbins	1.1
31			<chapter>
32			<title>Introduction</title>
33			<section>
34			<title>What is ALSA?</title>
35			<body>
36			<p>
37			The Advanced Linux Sound Architecture (ALSA) is a project to improve the Linux sound subsystem by rewriting
38			large chunks of it.
39			It is anticipated that ALSA will make it into Linux kernel 2.6.x (or 3.x.x -- whichever comes first) as it becomes ready.
40			</p>
41
42			<p>
43			ALSA provides audio and MIDI functionality for Linux.
44			</p>
45
46			<p>
47			Quoted from <uri>http://www.alsa-project.org</uri>, ALSA has the following features:
48			<ul><li> Efficient support for all types of audio interfaces, from consumer soundcards to professional multichannel audio interfaces.</li>
49			<li> Fully modularized sound drivers.</li>
50			<li> SMP and thread-safe design.</li>
51			<li> User space library (alsa-lib) to simplify application programming and provide higher level functionality.</li>
52			<li> Support for the older OSS API, providing binary compatibility for most OSS programs.</li>
53			</ul>
54			There's lots more to ALSA however, like support for Full Duplex playback and recording, multiple soundcard support,
55			hardware mixing of streams, extensive mixer capabilities (to support advanced features of new soundcards), ...
56			</p>
57			</body>
58			</section>
59			<section>
60			<title>Why use ALSA?</title>
61			<body>
62			<p>
63			If your soundcard is supported by the Linux kernel sound system or the commercial OSS/4Front sound driver system,
64			which can be found in all 2.4.x Linux kernels, you could just aswell build <e>those modules</e> for use with your soundcard.
65			If you want this, just read through the <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri>.
66			</p>
67			<p>
68			However, those OSS/4Front drivers have some limitations -- being commercial is one.
69			ALSA is an attempt to go beyond these limitations and to do so in an open source fashion.
70			ALSA is a fully GPL and LGPL'ed sound driver system, that provides a professional quality system for recording, playback,
71			and MIDI sequencing.
72			</p>
73			</body>
74			</section>
75			<section>
76			<title>What cards does ALSA support?</title>
77			<body>
78			<p>
79			ALSA tries to support as many (new) cards as possible by providing open-source drivers.
80			However, some vendors may provide binary-only packages.
81			</p>
82			<p>To know if your card is supported, you can find a Soundcard Matrix of supported and not-supported cards here:
83			<uri>http://www.alsa-project.org/alsa-doc/</uri>.
84			</p>
85			</body>
86			</section>
87			</chapter>
88
89			<chapter>
90			<title>Installation</title>
91			<section>
92			<title>Kernel modules</title>
93			<body>
94			<p>
95	seo	1.8	Since we're still using 2.4.x kernel sources, we'll have to compile kernel modules and ALSA modules separately. People who are using a 2.5.x kernel can do this from within their kernel configuration, since the ALSA modules are included in the kernel sources and should be built there.
96	drobbins	1.1	</p>
97			<p>
98			First we'll make sure that our kernel configuration is ready for use with ALSA.
99			All you need in your kernel configuration is having Sound Card Support set to be built as a module (M).
100			This will build <c>soundcore.o</c>.
101			</p>
102			<p>
103			<note>
104			Possibly, this will also work when you built Sound Card Support in the kernel (Y) instead of building it as a module (M).
105			However, the official ALSA documentation suggests building it as a module, since ALSA will try loading it.
106			</note>
107			</p>
108			<p>If you already have a working kernel configuration, make sure you remove all sound drivers (except for Sound Card Support).
109			If you wish to do this without having to reboot, you could do like this:
110			</p>
111			<pre>
112			# <c>cd /usr/src/linux</c>
113	zhen	1.4	# <c>cp .config ~/</c>
114	drobbins	1.1	# <c>make mrproper</c>
115			# <c>cp ~/.config .</c>
116			# <c>make menuconfig</c>
117			</pre>
118			<p>
119			Now select <e>Sound Card Support</e> as Module (M) and deselect all other sound drivers.
120			Exit and say Y to save your kernel configuration.
121			After that, build the modules:
122			</p>
123			<pre>
124			# <c>make dep clean</c>
125			# <c>make modules modules_install</c>
126			</pre>
127			<p>
128			Before installing your new modules, this last line will delete all your previous modules,
129			even the ones from a previous ALSA installation.
130			</p>
131			<p>
132			<impo>
133			This means, whenever you recompile your kernel later on, you MUST recompile <c>alsa-driver</c>.
134			</impo>
135			</p>
136			<p>
137			<note>However, there's no need to reinstall <c>nvidia-kernel</c>, the Nvidia drivers are in a separate directory
138			in <path>/lib/modules/*/video</path> and won't get deleted by a <c>make modules modules_install</c>
139			</note>
140			</p>
141			</body>
142			</section>
143
144			<section>
145			<title>ALSA modules</title>
146			<body>
147
148			<p>
149			Now it's time to install the ALSA drivers for your soundcard(s). If your soundcard is PCI, you can find out the name
150			and type of your soundcard by looking at the output of /proc/pci
151	seo	1.8	<pre># <c>grep audio /proc/pci</c></pre>
152	drobbins	1.1	</p>
153
154			<p>
155			<warn>
156			If you had a previous sound setup and there are still non-ALSA sound modules loaded, unload them <e>now</e>.
157			Check with <c>lsmod</c> and use <c>rmmod</c> to unload all sound-related modules on your system.
158			</warn>
159			</p>
160
161			<p>
162			We could simply do an <c>emerge alsa-driver</c> now, this would compile and install <e>all</e> ALSA sound drivers.
163			</p>
164			<p>
165			However, to save some time, lookup the <e>Module Name</e> of your soundcard(s) on the
166	seo	1.8	<uri link="http://www.alsa-project.org/alsa-doc">ALSA Soundcard Matrix</uri> by following the <e>Details</e> link in the <e>Driver and Docs</e> column in the row of the chipset of your soundcard.
167			Mine is <c>snd-emu10k1</c>, since I have an SBlive! soundcard, with the <e>EMU10K1</e> chipset.
168			We'll set ALSA_CARDS environment to the value of the module name before emerging (but without the snd prefix), so emerge will only compile the drivers we need.
169	drobbins	1.1	</p>
170
171			<p>
172			<pre>
173			# <c>env ALSA_CARDS='emu10k1' emerge alsa-driver</c>
174			</pre>
175			</p>
176			<p>
177			<note>
178	seo	1.8	You can also add this value in <path>/etc/make.conf</path>, so when you have to emerge the alsa-driver later on you can just run <c>emerge alsa-driver</c>.
179			For example, like this: <c>echo 'ALSA_CARDS="emu10k1"' >> /etc/make.conf</c>
180			</note>
181
182			<note>
183	drobbins	1.1	When you want to install ALSA drivers for more than one soundcard, you could set ALSA_CARDS to a space-separated list
184			of drivers; like this: <c>env ALSA_CARDS='emu10k1 intel8x0 ens1370' emerge alsa-driver</c>
185			</note>
186
187			<note>If you want to have OSS compatibility, make sure to emerge <i>alsa-oss</i>, it is the ALSA/OSS compatibility
188			wrapper. </note>
189
190			</p>
191			<p>
192			After this, the ALSA modules should be installed on your system.
193			</p>
194			</body>
195			</section>
196			<section>
197			<title>Configuration of ALSA</title>
198			<body>
199			<p>
200			Let's start configuring now to get ALSA working properly.
201			We'll need to edit some files, to let our system know about the freshly installed ALSA modules.
202			</p>
203	swift	1.12
204	drobbins	1.1	<p>
205	swift	1.12	First, install <c>alsa-utils</c> on your system:
206			</p>
207
208			<pre caption = "Emerging alsa-utils">
209			# <i>emerge alsa-utils</i>
210			</pre>
211
212			<p>
213			Hereafter, we need to edit <path>/etc/modules.d/alsa</path>.
214	drobbins	1.1	</p>
215			<warn>
216			There is no need to edit <path>/etc/modules.conf</path>. Instead, always edit files in <path>/etc/modules.d</path>.
217			</warn>
218			<p>
219	zhen	1.7	Check the ALSA portion <e>at the bottom of the file</e>.
220			By tweaking this line you can specify the max number of soundcards you have (generally, just one).
221	drobbins	1.1	</p>
222			<p>
223	seo	1.8	<pre caption="At the bottom of /etc/modules.d/alsa">
224			# Set this to the correct number of cards.
225			<c>options snd cards_limit=1</c>
226	drobbins	1.1	</pre>
227			</p>
228			<p>
229			Now we'll specify the sounddriver(s) ALSA should use. In the same file, edit like this:
230	seo	1.8	<pre caption="In /etc/modules.d/alsa">
231	drobbins	1.1	## and then run `update-modules' command.
232			## Read alsa-driver's INSTALL file in /usr/share/doc for more info.
233			##
234			## ALSA portion
235			<c>alias snd-card-0 snd-emu10k1</c>
236			<c>## If you have more than one, add:
237			## alias snd-card-1 snd-intel8x0
238			## alias snd-card-2 snd-ens1370</c>
239			## OSS/Free portion
240			## alias sound-slot-0 snd-card-0
241			## alias sound-slot-1 snd-card-1
242			##
243			</pre>
244			</p>
245			<p>
246			<note>
247	zhen	1.6	If you have more than one soundcard, adjust the <c>cards_limit</c> value and add more snd-card aliases to the file.
248	drobbins	1.1	I don't have experience with this, but you can find examples for configurations with two or more soundcards in
249			<uri link="http://www.alsa-project.org/alsa-doc/alsa-howto/c1660.htm">Chapter 6</uri>
250			of the <uri link="http://www.alsa-project.org/alsa-doc/alsa-howto/alsa-howto.html">ALSA Howto</uri>.
251			</note>
252			</p>
253			<p>
254	seo	1.8	Last thing to do in this file, almost at the end, check if these lines are there and uncommented:
255			<pre caption="Near the end of /etc/modules.d/alsa">
256	drobbins	1.1	alias /dev/mixer snd-mixer-oss
257			alias /dev/dsp snd-pcm-oss
258			alias /dev/midi snd-seq-oss
259			</pre>
260			</p>
261			<p>
262			Now double-check the file <path>/etc/modules.d/alsa</path> and when you're sure everyting is ok, run <c>update-modules</c>.
263			<pre>
264			# <c>update-modules</c>
265			</pre>
266			</p>
267			<note>
268			Running <c>update-modules</c> here will insert the data from <path>/etc/modules.d/alsa</path> into <path>/etc/modules.conf</path>
269			</note>
270			<p>
271			You should also verify that /etc/devfsd.conf has the alsa devices and permissions correctly registered.
272			</p>
273	seo	1.8	<pre caption="/etc/devfsd.conf">
274	drobbins	1.1	# ALSA/OSS stuff
275			# Comment/change these if you want to change the permissions on
276			# the audio devices
277			LOOKUP snd MODLOAD ACTION snd
278			LOOKUP dsp MODLOAD
279			LOOKUP mixer MODLOAD
280			LOOKUP midi MODLOAD
281			REGISTER sound/.* PERMISSIONS root.audio 660
282			REGISTER snd/.* PERMISSIONS root.audio 660
283			</pre>
284			<note>
285			Notice that devfsd.conf sets /dev/sound permissions to be root.audio. Thus, for non-root users to use audio they will have to be part of the audio group.
286			</note>
287			</body>
288			</section>
289			</chapter>
290			<chapter>
291			<title>Starting ALSA</title>
292			<section>
293			<title>Adding alsasound to a runlevel</title>
294			<body>
295			<p>
296			First thing to do now, is to make ALSA startup at boottime. Like this:
297			<pre>
298			# <c>rc-update add alsasound boot</c>
299			</pre>
300			</p>
301			<p>
302			<warn>Note that the alsasound script should be added to the "boot" runlevel, not the "default" runlevel.</warn>
303			</p>
304			</body>
305			</section>
306			<section>
307			<title>Running and unmuting</title>
308			<body>
309			<p>
310			Since we're Linux users, we don't want to reboot. So we'll start the alsasound script manually.
311			</p>
312			<pre>
313			# <c>/etc/init.d/alsasound start</c>
314			</pre>
315			<p>
316			ALSA is running now. If everything is ok, you should be able to see the ALSA modules loaded when running <c>lsmod</c>.
317	swift	1.12	However, sound won't work yet, because the channels are still muted. We need <c>amixer</c> for this.
318	drobbins	1.1	</p>
319	swift	1.12	<pre caption = "Running amixer">
320			# <i>amixer</i>
321	drobbins	1.1	</pre>
322			<p>
323			<warn>
324			You shouldn't get this, but <e>if</e> you get an error about "amixer: Mixer attach default error: No such file or directory", you should manually insmod
325			<c>snd-mixer-oss</c> and <c>snd-pcm-oss</c> once. After that run amixer again.
326			</warn>
327			</p>
328			<pre caption="only if you get an error when running amixer">
329			# <c>insmod snd-mixer-oss</c>
330			# <c>insmod snd-pcm-oss</c>
331			# <c>amixer</c>
332			</pre>
333			<p>
334			If you got this far, now unmute both Master and PCM channels.
335			</p>
336			<p>
337			<pre>
338			# <c>amixer set Master 100 unmute</c>
339			# <c>amixer set PCM 100 unmute</c>
340	swift	1.9	# <c>aplay $KDEDIR/share/sounds/pop.wav</c> <codenote>(pop.wav is part of KDE)</codenote>
341	drobbins	1.1	</pre>
342			</p>
343			We check to see if sound is working by using the aplay (alsa play) command. If you hear a pop, then sound is indeed working.
344			Then, adjust the volume settings to your liking; the ncurses-based <c>alsamixer</c> is a great way to get them "just so".
345			<p>
346			You may want to emerge <c>alsa-xmms</c> as that will provide ALSA support for XMMS.
347			</p>
348			When you reboot your system, the <e>alsasound</e> init script will properly save and restore your volume settings.
349			</body>
350			</section>
351			</chapter>
352			<chapter>
353			<title>Final Notes</title>
354			<section>
355			<title>After kernel-upgrades..</title>
356			<body>
357			<p>When you ever rebuild your kernel, or upgrade to another kernel, you'll have to rebuild the ALSA modules.</p>
358			<p>Although you might have installed <c>alsa-driver</c>, <c>alsa-libs</c> and <c>alsa-utils</c>, only the first will
359			have to be installed again, since it will put the alsa modules in
360			<path>/lib/modules/*/kernel/sound/pci/</path>.</p>
361			<pre caption="needed after each kernel compile">
362	seo	1.8	# <c>emerge alsa-driver</c>
363	drobbins	1.1	</pre>
364			</body>
365			</section>
366			<section>
367			<title>/etc/modules.autoload</title>
368			<body>
369			<p>You won't have to edit this file for use with ALSA. After our <c>rc-update add alsasound boot</c>, our system will
370			load the correct modules at startup.</p>
371			<p>It's not necessary to add <c>snd-pcm-oss</c> or <c>snd-mixer-oss</c> in this file.
372			Check the <uri link="http://www.djcj.org/LAU/guide/alsbook/faq1.html">this FAQ</uri> for more info.</p>
373			</body>
374			</section>
375			<section>
376			<title>More links..</title>
377			<body>
378			<p>
379			You could check these for additional info:
380			</p>
381			<p>
382			<ul>
383	seo	1.8	<li><uri link="http://www.gentoo.org/doc/en/desktop.xml">The Gentoo Linux Desktop Configuration Guide</uri></li>
384	drobbins	1.1	<li><uri link="http://www.alsa-project.org">ALSA Project Homepage</uri></li>
385			<li><uri link="http://www.alsa-project.org/documentation.php3">ALSA Users Documentation</uri></li>
386			<li><uri link="http://www.djcj.org">ALSA Howto's and FAQ's</uri></li>
387			<li><uri link="http://tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri></li>
388			<li><uri link="http://linux-sound.org/">Sound and MIDI Software For Linux</uri></li>
389			</ul>
390			</p>
391			</body>
392			</section>
393			</chapter>
394			</guide>