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1<?xml version='1.0' encoding="UTF-8"?> 1<?xml version='1.0' encoding="UTF-8"?>
2<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/alsa-guide.xml,v 1.53 2005/06/08 19:54:07 fox2mike Exp $ -->
3
2<!DOCTYPE guide SYSTEM "/dtd/guide.dtd"> 4<!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
3 5
4<guide link = "/doc/en/alsa-guide.xml"> 6<guide link="/doc/en/alsa-guide.xml">
5<title>Gentoo Linux ALSA Guide</title> 7<title>Gentoo Linux ALSA Guide</title>
6<author title="Author"><mail link="zu@pandora.be"> 8
7 Vincent Verleye</mail> 9<author title="Author">
10 <mail link="fox2mike@gentoo.org">Shyam Mani</mail>
8</author> 11</author>
9<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<author title="Editor"><mail link="zhen@gentoo.org">
16 John P. Davis</mail>
17</author>
18<author title="Editor"><mail link="swift@gentoo.org">
19 Sven Vermeulen</mail>
20</author>
21<author title="Editor"><mail link="bennyc@gentoo.org">
22 Benny Chuang</mail>
23</author>
24<author title="Editor"><mail link="blubber@gentoo.org">
25 Tiemo Kieft</mail>
26</author>
27 12
13<abstract>
14This document helps a user setup ALSA on Gentoo Linux.
15</abstract>
16
17<!-- The content of this document is licensed under the CC-BY-SA license -->
18<!-- See http://creativecommons.org/licenses/by-sa/2.0 -->
28<license/> 19<license/>
29 20
30<abstract>
31This guide will show you how to set up the Advanced Linux Sound Architecture (ALSA) on Gentoo Linux.
32In addition to the Gentoo Linux Desktop Configuration Guide, this guide is supposed to give you more information on this subject. </abstract>
33
34<version>1.3.3</version> 21<version>2.2</version>
35<date>October 9, 2003</date> 22<date>2005-06-09</date>
36 23
37<chapter> 24<chapter>
38<title>Introduction</title> 25<title>Introduction</title>
39<section> 26<section>
40 <title>What is ALSA?</title> 27<title>What is ALSA?</title>
28<body>
29
30<p>
31ALSA, which stands for <e>Advanced Linux Sound Architecture</e>, provides
32audio and MIDI (<e>Musical Instrument Digital Interface</e>) functionality to
33the Linux operating system. ALSA is the default sound subsystem in the 2.6
34kernel thereby replacing OSS (<e>Open Sound System</e>), which was used in the
352.4 kernels.
36</p>
37
38<p>
39ALSA's main features include efficient support for all types of audio
40interfaces ranging from consumer sound cards to professional sound
41equipment, fully modularized drivers, SMP and thread safety, backward
42compatibility with OSS and a user-space library <c>alsa-lib</c> to make
43application development a breeze.
44</p>
45
41<body> 46</body>
42<p> 47</section>
43The Advanced Linux Sound Architecture (ALSA) is a project to improve the Linux sound subsystem by rewriting 48<section>
44large chunks of it. 49<title>ALSA on Gentoo</title>
45It is anticipated that ALSA will make it into Linux kernel 2.6.x (or 3.x.x -- whichever comes first) as it becomes ready. 50<body>
51
46</p> 52<p>
47 53One of Gentoo's main strengths lies in giving the user maximum control over
54how a system is installed/configured. ALSA on Gentoo follows the same
55principle. There are two ways you can get ALSA support up and running on your
56system. We shall look at them in detail in the next chapter.
48<p> 57</p>
49ALSA provides audio and MIDI functionality for Linux. 58
59</body>
60</section>
61</chapter>
62
63<chapter>
64<title>Installing ALSA</title>
65<section>
66<title>Options</title>
67<body>
68
69<warn>
70The methods shown below are mutually exclusive. You cannot have ALSA compiled
71in your kernel and use <c>media-sound/alsa-driver</c>. It <e>will</e> fail.
72</warn>
73
74<impo>
75<c>genkernel</c> users have their config built such a way that the ALSA
76sub-system in the kernel is active. Therefore <c>genkernel</c> users can
77proceed to the <uri link="#alsa-utilities">ALSA Utilities</uri> section
78directly.
79</impo>
80
50</p> 81<p>
51 82The two options are :
52<p> 83</p>
53Quoted from <uri>http://www.alsa-project.org</uri>, ALSA has the following features: 84
54<ul><li> Efficient support for all types of audio interfaces, from consumer soundcards to professional multichannel audio interfaces.</li> 85<ol>
55 <li> Fully modularized sound drivers.</li> 86 <li>
56 <li> SMP and thread-safe design.</li> 87 Use ALSA provided by your kernel. This is the preferred/recommended
57 <li> User space library (alsa-lib) to simplify application programming and provide higher level functionality.</li> 88 method.
58 <li> Support for the older OSS API, providing binary compatibility for most OSS programs.</li> 89 </li>
90 <li>
91 Use Gentoo's <c>media-sound/alsa-driver</c> package.
92 </li>
93</ol>
94
95<p>
96We shall take a peek into both before finally deciding on one.
97</p>
98
99<p>
100If you were to use ALSA provided by the kernel, the following are the pros and
101cons :
102</p>
103
104<table>
105<tr>
106 <th>Kernel ALSA</th>
107 <th>Pros and Cons</th>
108</tr>
109<tr>
110 <th>+</th>
111 <ti>Pretty stable as drivers are integrated into kernel.</ti>
112</tr>
113<tr>
114 <th>+</th>
115 <ti>One shot solution, no repeating emerges.</ti>
116</tr>
117<tr>
118 <th>-</th>
119 <ti>Might be a slightly older version than <c>alsa-driver</c>.</ti>
120</tr>
121</table>
122
123<p>
124And, if you were to use alsa-driver,
125</p>
126
127<table>
128<tr>
129 <th>alsa-driver</th>
130 <th>Pros and Cons</th>
131</tr>
132<tr>
133 <th>+</th>
134 <ti>Latest drivers from the ALSA Project.</ti>
135</tr>
136<tr>
137 <th>-</th>
138 <ti>Every kernel recompile requires a re-emerge of <c>alsa-driver</c>.</ti>
139</tr>
140<tr>
141 <th>-</th>
142 <ti>Needs certain kernel config options disabled to work correctly.</ti>
143</tr>
144</table>
145
146</body>
147</section>
148<section>
149<title>So...</title>
150<body>
151
152<p>
153The main difference between using <c>alsa-driver</c> and ALSA that comes with
154the kernel is that <c>alsa-driver</c> is generally more up to date than the
155version in the kernel. Since this does not make any huge difference as
156such, you are encouraged to use the ALSA provided by the kernel.
157</p>
158
159</body>
160</section>
161<section id="lspci">
162<title>Before you proceed</title>
163<body>
164
165<p>
166Whichever method of install you choose, you need to know what drivers your
167sound card uses. <c>lspci</c> will help you in digging out the required
168information. Please <c>emerge sys-apps/pciutils</c> to get <c>lspci</c>, if
169you don't have it installed already. We now proceed to find out details about
170the sound card.
171</p>
172
173<pre caption="Soundcard Details">
174# <i>lspci -v | grep -i audio</i>
1750000:00:0a.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 06)
176</pre>
177
178<p>
179We now know that the sound card on the machine is a Sound Blaster Live! and
180the card manufacturer is Creative Labs. Head over to the
181<uri link="http://www.alsa-project.org/alsa-doc/"> ALSA Soundcard Matrix</uri>
182page and select Creative Labs from the drop down menu. You will be taken to
183the Creative Labs matrix page where you can see that the SB Live! uses the
184<c>emu10k1</c> module. That is the information we need for now. If you are
185interested in detailed information, you can click on the link next to the
186"Details" and that will take you to the <c>emu10k1</c> specific page.
187</p>
188
189</body>
190</section>
191<section id="kernel">
192<title>Using ALSA provided by your Kernel</title>
193<body>
194
195<p>
196If you're a person who likes to keep things simple like I do, then this is
197the way to go.
198</p>
199
200<note>
201Since the 2005.0 release, Gentoo Linux uses 2.6 as the default kernel. Unless
202you are specifically using the 2.4 profile, <c>gentoo-sources</c> will be a
2032.6 kernel on <e>most</e> architectures. Please check that your kernel is a
2042.6 series kernel. This method will <e>not</e> work on a 2.4 kernel.
205</note>
206
207<p>
208Let us now configure the kernel to enable ALSA.
209</p>
210
211<pre caption="Heading over to the source">
212# <i>cd /usr/src/linux</i>
213# <i>make menuconfig</i>
214</pre>
215
216<note>
217The above example assumes that <path>/usr/src/linux</path> symlink points to
218the kernel sources you want to use. Please ensure the same before proceeding.
219</note>
220
221<p>
222Now we will look at some of the options we will have to enable in the 2.6
223kernel to ensure proper ALSA support for our sound card.
224</p>
225
226<note>
227Please note that for the sake of ease, all examples show a modular kernel. It
228is advisable to follow the same. Please do <e>not</e> skip the
229<uri link="#alsa-config">Configuration</uri> section of this document. If
230you still like to have options built-in, ensure that you make changes to your
231config accordingly.
232</note>
233
234<pre caption="Kernel Options for ALSA">
235Device Drivers ---&gt;
236 Sound ---&gt;
237
238<comment>(This needs to be enabled)</comment>
239&lt;M&gt; Sound card support
240
241<comment>(Make sure OSS is disabled)</comment>
242Open Sound System ---&gt;
243 &lt; &gt; Open Sound System (DEPRECATED)
244
245<comment>(Move one step back and enter ALSA)</comment>
246Advanced Linux Sound Architecture ---&gt;
247 &lt;M&gt; Advanced Linux Sound Architecture
248 <comment>(Select this if you want MIDI sequencing and routing)</comment>
249 &lt;M&gt; Sequencer support
250 <comment>(Old style /dev/mixer* and /dev/dsp* support. Recommended.)</comment>
251 &lt;M&gt; OSS Mixer API
252 &lt;M&gt; OSS PCM (digital audio) API
253
254<comment>(You now have a choice of devices to enable support for. Generally,
255you will have one type of device and not more. If you have more than one
256sound card, please enable them all here.)</comment>
257
258<comment>(Mostly for testing and development purposes, not needed for normal
259users unless you know what you are doing.)</comment>
260Generic devices ---&gt;
261
262<comment>(For ISA Sound cards)</comment>
263ISA devices ---&gt;
264<comment>(IF you had the Gravis, you would select this option)</comment>
265 &lt;M&gt; Gravis UltraSound Extreme
266
267<comment>(Move one level back and into PCI devices. Most sound cards today are
268PCI devices)</comment>
269PCI devices ---&gt;
270 <comment>(We now select the emu10k1 driver for our card)</comment>
271 &lt;M&gt; Emu10k1 (SB Live!, Audigy, E-mu APS)
272 <comment>(Or an Intel card would be)</comment>
273 &lt;M&gt; Intel/SiS/nVidia/AMD/ALi AC97 Controller
274 <comment>(Or if you have a VIA Card)</comment>
275 &lt;M&gt; VIA 82C686A/B, 8233/8235 AC97 Controller
276
277<comment>(Move one level back and select in case you have an USB sound card)</comment>
278USB Devices ---&gt;
279</pre>
280
281<p>
282Now that your options are set, you can (re)compile the kernel and ALSA support
283for your card should be functional once you reboot into the new kernel.
284You can now proceed to <uri link="#alsa-utilities">ALSA Utilities</uri> and
285see if everything is working as it should.
286</p>
287
288</body>
289</section>
290<section id="alsa-driver">
291<title>Using the ALSA Driver package</title>
292<body>
293
294<p>
295So you've decided to go the <c>alsa-driver</c> way. Let's get started then.
296There are a few minor things to be done to ensure only the drivers for your
297sound card are compiled. Although this is not really necessary, it cuts down
298on the unnecessary drivers that will be compiled otherwise.
299</p>
300
301<p>
302If you don't have an idea of what drivers your sound card might need, please
303take a look at the <uri link="#lspci">lspci</uri> section of this guide. Once
304you have your driver name (<c>emu10k1</c> in our example), edit
305<path>/etc/make.conf</path> and add a variable, <c>ALSA_CARDS</c>.
306</p>
307
308<pre caption="Adding ALSA_CARDS to make.conf">
309<comment>(For one sound card)</comment>
310ALSA_CARDS="emu10k1"
311<comment>(For more than one, seperate names with spaces)</comment>
312ALSA_CARDS="emu10k1 via82xx"
313</pre>
314
315<p>
316If you have compiled your kernel and want to use <c>alsa-driver</c>, please
317ensure the following before proceeding, else <c>alsa-driver</c> is likely to
318fail. The next code listing gives you one way of performing the checks.
319</p>
320
321<ol>
322 <li>
323 <c>CONFIG_SOUND</c> is set. (Basic Sound support enabled)
324 </li>
325 <li>
326 <c>CONFIG_SOUND_PRIME</c> is not set. (In-built OSS support disabled)
327 </li>
328 <li>
329 <c>CONFIG_SND</c> is not set. (In-built ALSA support disabled)
330 </li>
331 <li>
332 <path>/usr/src/linux</path> points to the kernel you want ALSA working on.
333 </li>
334</ol>
335
336<pre caption=".config checks">
337<comment>(Assuming the linux symlink points to the correct kernel)</comment>
338# <i>cd /usr/src/linux</i>
339# <i>grep SOUND .config</i>
340<comment>(1. is true)</comment>
341CONFIG_SOUND=y
342<comment>(2. is true)</comment>
343CONFIG_SOUND_PRIME is not set
344# <i>grep SND .config</i>
345<comment>(and 3. is true)</comment>
346CONFIG_SND is not set
347</pre>
348
349<p>
350Now all you have to do is type the magic words...and no, its not abracadabra.
351</p>
352
353<pre caption="Installing alsa-driver">
354# <i>emerge alsa-driver</i>
355</pre>
356
357<impo>
358Please note that you will have to run <c>emerge alsa-driver</c> after every
359kernel (re)compile, as the earlier drivers are deleted.
360</impo>
361
362</body>
363</section>
364</chapter>
365
366<chapter>
367<title>Configuring/Testing ALSA</title>
368<section id="alsa-utilities">
369<title>ALSA Utilities</title>
370<body>
371
372<p>
373<c>alsa-utils</c> forms an integral part of ALSA as it has a truckload of
374programs that are highly useful, including the ALSA Initscripts. Hence we
375strongly recommend that you install <c>alsa-utils</c>
376</p>
377
378<pre caption="Install alsa-utils">
379# <i>emerge alsa-utils</i>
380</pre>
381
382<note>
383If you activated ALSA in your <uri link="#kernel">kernel</uri> <e>and</e> did
384not compile ALSA as modules, please proceed to the
385<uri link="#initscript">ALSA Initscript</uri> section. The rest of you need
386to configure ALSA. This is made very easy by the existence of the
387<c>alsaconf</c> tool provided by <c>alsa-utils</c>.
388</note>
389
390</body>
391</section>
392<section id="alsa-config">
393<title>Configuration</title>
394<body>
395
396<note>
397Please shut down any programs that <e>might</e> access the sound card while
398running <c>alsaconf</c>.
399</note>
400
401<p>
402The easiest way to configure your sound card is to run <c>alsaconf</c>. Just
403type <c>alsaconf</c> in a shell as root.
404</p>
405
406<pre caption="Invoking alsaconf">
407# <i>alsaconf</i>
408</pre>
409
410<p>
411You will now see a neat menu guided interface that will automatically probe
412your devices and try to find out your sound card. You will be asked to pick
413your sound card from a list. Once that's done, it will ask you permission to
414automatically make required changes to <path>/etc/modules.d/alsa</path>.
415It will then adjust your volume settings to optimum levels and run
416<c>modules-update</c> and starts the <path>/etc/init.d/alsasound</path>
417service. Once <c>alsaconf</c> exits, you can proceed with setting up the ALSA
418initscript.
419</p>
420
421</body>
422</section>
423<section id="initscript">
424<title>ALSA Initscript</title>
425<body>
426
427<p>
428We're now almost all setup. Whichever method you chose to install ALSA, you'll
429need to have something load your modules or initialize ALSA and restore your
430volume settings when your system comes up. The ALSA Initscript handles all of
431this for you and is called <c>alsasound</c>. Add it to the default run-level.
432</p>
433
434<pre caption="Adding ALSA to default">
435# <i>rc-update add alsasound default</i>
436 * alsasound added to runlevel default
437 * rc-update complete.
438</pre>
439
440<p>
441Next, just check the <path>/etc/conf.d/alsasound</path> file and ensure that
442SAVE_ON_STOP variable is set to yes. This saves your sound settings when you
443shutdown your system.
444</p>
445
446</body>
447</section>
448<section>
449<title>Volume Check!</title>
450<body>
451
452<p>
453We've completed all the setups and pre-requisites, so let's fire up ALSA. If
454you ran <c>alsaconf</c>, you can skip this step, since <c>alsaconf</c> already
455does this for you.
456</p>
457
458<pre caption="Start the service">
459<comment>(Modular Kernels)</comment>
460# <i>/etc/init.d/alsasound start</i>
461 * Loading ALSA modules ...
462 * Loading: snd-card-0 ... [ ok ]
463 * Loading: snd-pcm-oss ... [ ok ]
464 * Loading: snd-seq ... [ ok ]
465 * Loading: snd-emu10k1-synth ... [ ok ]
466 * Loading: snd-seq-midi ... [ ok ]
467 * Restoring Mixer Levels ... [ ok ]
468<comment>(ALSA compiled in)</comment>
469# <i>/etc/init.d/alsasound start</i>
470 * Loading ALSA modules ...
471 * Restoring Mixer Levels ... [ ok ]
472</pre>
473
474<p>
475Now that the required things have been take care of, we need to check up on
476the volume as in certain cases, it is muted. We use <c>alsamixer</c> for this purpose.
477</p>
478
479<pre caption="Starting alsamixer">
480<comment>(Opens up a console program. Only required settings are shown)</comment>
481# <i>alsamixer</i>
482</pre>
483
484<p>
485This is how the ALSA Mixer <e>might</e> look the first time you open it. Pay
486attention to the Master and PCM channels which both have an MM below them.
487That means they are muted. If you try to play anything with <c>alsamixer</c>
488in this state, you will not hear anything on your speakers.
489</p>
490
491<figure link="/images/docs/alsa-mixermuted.png" short="AlsaMixer Muted" caption="The Alsa Mixer Main Window, Muted"/>
492
493<p>
494Now, we shall unmute the channels, and set volume levels as needed.
495</p>
496
497<warn>
498Both Master <e>and</e> PCM need to be unmuted and set to audible volume levels if
499you want to hear some output on your speakers.
500</warn>
501
502<ul>
503 <li>
504 To move between channels, use your left and right arrow keys. (&lt;-
505 &amp; -&gt;)
506 </li>
507 <li>
508 To toggle mute, move to the specific channel, for example Master and press
509 the <e>m</e> key on the keyboard.
510 </li>
511 <li>
512 To increase and decrease the volume levels, use the up and down arrow keys
513 respectively.
514 </li>
59</ul> 515</ul>
60There's lots more to ALSA however, like support for Full Duplex playback and recording, multiple soundcard support, 516
61hardware mixing of streams, extensive mixer capabilities (to support advanced features of new soundcards), ... 517<note>
518Be careful when setting your Bass and Treble values. 50 is usually a good
519number for both. Extremely high values of Bass may cause <e>jarring</e>
520on speakers that are not designed to handle them.
521</note>
522
62</p> 523<p>
524After you're all done, your ALSA Mixer should look similar to the one below.
525Note the 00 instead of the MM and also the volume levels for some optimum
526settings.
527</p>
528
529<figure link="/images/docs/alsa-mixerunmuted.png" short="AlsaMixer Unmuted" caption="Alsa Mixer ready to roll"/>
530
63</body> 531</body>
64</section>
65<section> 532</section>
66 <title>Why use ALSA?</title>
67<body>
68<p>
69If your soundcard is supported by the Linux kernel sound system or the commercial OSS/4Front sound driver system,
70which can be found in all 2.4.x Linux kernels, you could just aswell build <e>those modules</e> for use with your soundcard.
71If you want this, just read through the <uri link="http://www.tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri>.
72</p>
73<p>
74However, those OSS/4Front drivers have some limitations -- being commercial is one.
75ALSA is an attempt to go beyond these limitations and to do so in an open source fashion.
76ALSA is a fully GPL and LGPL'ed sound driver system, that provides a professional quality system for recording, playback,
77and MIDI sequencing.
78</p>
79</body>
80</section> 533<section>
534<title>Sound Check!</title>
535<body>
536
537<p>
538Finally. Some music. If everything above is perfect, you should be able to now
539listen to some good music. A quick way to test is to use a command line tool
540like <c>media-sound/madplay</c>. You could also use something more well known
541like <c>mpg123</c> or <c>xmms</c>. If you are an ogg fan, you could use
542<c>ogg123</c> provided by <c>media-sound/vorbis-tools</c>. Use any player you
543are comfortable with. As always, <c>emerge</c> what you need.
544</p>
545
546<pre caption="Getting the software">
547<comment>(Install the applications you want)</comment>
548# <i>emerge madplay mpg123 xmms</i>
549<comment>(To play .ogg files)</comment>
550# <i>emerge vorbis-tools</i>
551</pre>
552
553<p>
554And then play your favorite sound track...
555</p>
556
557<pre caption="Playing Music">
558# <i>madplay -v /mnt/shyam/Music/Paul\ Oakenfold\ -\ Dread\ Rock.mp3</i>
559MPEG Audio Decoder 0.15.2 (beta) - Copyright (C) 2000-2004 Robert Leslie et al.
560 Title: Dread Rock
561 Artist: Paul Oakenfold
562 Album: Matrix Reloaded
563 Year: 2003
564 Genre: Soundtrack
565 Soundtrack
566 00:04:19 Layer III, 160 kbps, 44100 Hz, joint stereo (MS), no CRC
567
568# <i>ogg123 Paul\ Oakenfold\ -\ Dread\ Rock.ogg</i>
569Audio Device: Advanced Linux Sound Architecture (ALSA) output
570
571Playing: Paul Oakenfold - Dread Rock.ogg
572Ogg Vorbis stream: 2 channel, 44100 Hz
573Genre: Soundtrack
574Transcoded: mp3;160
575Title: Dread Rock
576Artist: Paul Oakenfold
577Date: 2003
578Album: Matrix Reloaded
579Time: 00:11.31 [04:28.75] of 04:40.06 (200.6 kbps) Output Buffer 96.9%
580</pre>
581
582</body>
81<section> 583</section>
82 <title>What cards does ALSA support?</title> 584<section>
585<title>Issues?</title>
83<body> 586<body>
84<p> 587
85ALSA tries to support as many (new) cards as possible by providing open-source drivers.
86However, some vendors may provide binary-only packages.
87</p> 588<p>
88<p>To know if your card is supported, you can find a Soundcard Matrix of supported and not-supported cards here: 589If for some reason you're unable to hear sound, the first thing to do would
89<uri>http://www.alsa-project.org/alsa-doc/</uri>. 590be to check your <uri link="#doc_chap3_pre5">alsamixer</uri> settings. 80% of
591the issues lie with muted channels or low volume. Also check your Window
592Manager's sound applet and verify that volumes are set to audible levels.
593</p>
594
90</p> 595<p>
596<path>/proc</path> is your friend. And in this case, <path>/proc/asound</path>
597is your best friend. We shall just take a short look at how much info is made
598available to us there.
599</p>
600
601<pre caption="Fun with /proc/asound">
602<comment>(First and foremost, if /proc/asound/cards shows your card, ALSA has
603picked up your sound card fine.)</comment>
604# <i>cat /proc/asound/cards</i>
6050 [Live ]: EMU10K1 - Sound Blaster Live!
606 Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
607
608<comment>(If you run ALSA off the kernel like I do and wonder how far behind
609you are from alsa-driver, this displays current running ALSA version)</comment>
610# <i>cat /proc/asound/version</i>
611Advanced Linux Sound Architecture Driver Version 1.0.8 (Thu Jan 13 09:39:32 2005 UTC).
612
613<comment>(ALSA OSS emulation details)</comment>
614# <i>cat /proc/asound/oss/sndstat</i>
615Sound Driver:3.8.1a-980706 (ALSA v1.0.8 emulation code)
616Kernel: Linux airwolf.zion 2.6.11ac1 #2 Wed May 4 00:35:08 IST 2005 i686
617Config options: 0
618
619Installed drivers:
620Type 10: ALSA emulation
621
622Card config:
623Sound Blaster Live! (rev.6, serial:0x80271102) at 0xb800, irq 11
624
625Audio devices:
6260: EMU10K1 (DUPLEX)
627
628Synth devices: NOT ENABLED IN CONFIG
629
630Midi devices:
6310: EMU10K1 MPU-401 (UART)
632
633Timers:
6347: system timer
635
636Mixers:
6370: SigmaTel STAC9721/23
638</pre>
639
91</body> 640</body>
92</section> 641</section>
93</chapter> 642</chapter>
94 643
95<chapter> 644<chapter>
96<title>Installation</title> 645<title>Other things ALSA</title>
97<section>
98<title>Gentoo USE flags</title>
99<body>
100
101<p>
102To compile programs with ALSA-support, be sure to add <e>alsa</e> to
103your USE-variable. However, several tools don't support alsa yet, and
104require OSS. ALSA provides OSS-emulation if you define <e>oss</e> in your
105USE-variable before you start.
106</p>
107
108</body>
109</section> 646<section>
110 647<title>Setting up MIDI support</title>
111<section>
112 <title>Kernel modules</title>
113<body> 648<body>
114<p> 649
115Since 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.
116</p> 650<p>
651If your sound card is one of those that come with on-board MIDI synthesizers
652and you would like to listen to some .mid files, you have to install
653<c>awesfx</c> which is basically a set of utilities for controlling the AWE32
654driver. We need to install it first. If you don't have a hardware synthesizer,
655you can use a virtual one. Please see the section on
656<uri link="#vsynth">Virtual Synthesizers</uri> for more information.
117<p> 657</p>
118First we'll make sure that our kernel configuration is ready for use with ALSA. 658
119All you need in your kernel configuration is having Sound Card Support set to be built as a module (M). 659<pre caption="Installing awesfx">
120This will build <c>soundcore.o</c>. 660# <i>emerge awesfx</i>
121</p> 661</pre>
122<p> 662
123<note> 663<note>
124Possibly, this will also work when you built Sound Card Support in the kernel (Y) instead of building it as a module (M). 664You will need to copy over SoundFont (SF2) files from your sound card's driver
125However, the official ALSA documentation suggests building it as a module, since ALSA will try loading it. 665CD or a Windows installation into <path>/usr/share/sounds/sf2/</path>. For
666example a sound font file for the Creative SBLive! card would be 8MBGMSFX.SF2.
126</note> 667</note>
668
127</p> 669<p>
128<p>If you already have a working kernel configuration, make sure you remove all sound drivers (except for Sound Card Support). 670After copying over the Soundfont files, we can then play a midi file as shown.
129If you wish to do this without having to reboot, you could do like this: 671You can also add the <c>asfxload</c> command to
130</p> 672<path>/etc/conf.d/local.start</path>, so that the sound font is loaded
131<pre> 673every time the system starts up.
132# <i>cd /usr/src/linux</i>
133# <i>cp .config ~/</i>
134# <i>make mrproper</i>
135# <i>cp ~/.config .</i>
136# <i>make menuconfig</i>
137</pre>
138<p> 674</p>
139Now select <e>Sound Card Support</e> as Module (M) and deselect all other sound drivers. 675
140Exit and say Y to save your kernel configuration. 676<note>
141After that, build the modules: 677<path>/mnt</path> paths mentioned in the code listing(s) below will <e>not</e>
142</p> 678be the same in your machine. They are just an example. Please be careful to
143<pre> 679change the path to suit your machine.
144# <i>make dep clean</i>
145# <i>make modules modules_install</i>
146</pre>
147<p>
148Before installing your new modules, this last line will delete all your previous modules,
149even the ones from a previous ALSA installation.
150</p>
151<p>
152<impo>
153This means, whenever you recompile your kernel later on, you MUST recompile <c>alsa-driver</c>.
154</impo>
155</p>
156<p>
157<note>However, there's no need to reinstall <c>nvidia-kernel</c>, the Nvidia drivers are in a separate directory
158in <path>/lib/modules/*/video</path> and won't get deleted by a <c>make modules modules_install</c>
159</note> 680</note>
681
682<pre caption="Loading Soundfonts">
683<comment>(First, copy the Soundfont)</comment>
684# <i>cp /mnt/win2k/Program\ Files/CreativeSBLive2k/SFBank/8MBGMSFX.SF2 /usr/share/sounds/sf2/</i>
685<comment>(We load the specific Soundfont)</comment>
686# <i>asfxload /usr/share/sounds/sf2/8MBGMSFX.SF2</i>
687</pre>
688
160</p> 689<p>
161</body> 690You can now play midi files using a program like <c>aplaymidi</c>. Run
162</section> 691<c>aplaymidi -l</c> to get a list of available ports and then pick one
692to play the file on.
693</p>
163 694
695<pre caption="Playing MIDI">
696<comment>(Check open ports)</comment>
697# <i>aplaymidi -l</i>
698 Port Client name Port name
699 64:0 EMU10K1 MPU-401 (UART) EMU10K1 MPU-401 (UART)
700 65:0 Emu10k1 WaveTable Emu10k1 Port 0
701 65:1 Emu10k1 WaveTable Emu10k1 Port 1
702 65:2 Emu10k1 WaveTable Emu10k1 Port 2
703 65:3 Emu10k1 WaveTable Emu10k1 Port 3
704<comment>(Pick a port, and play a mid file)</comment>
705# <i> aplaymidi --port=65:0 /mnt/shyam/music/midi/mi2.mid</i>
706</pre>
707
708</body>
164<section> 709</section>
165 <title>ALSA modules</title> 710<section id="vsynth">
166<body> 711<title>Virtual Synthesizers</title>
167
168<p>
169Now it's time to install the ALSA drivers for your soundcard(s). If your soundcard is PCI, you can find out the name
170and type of your soundcard by looking at the output of /proc/pci.
171</p>
172<pre>
173# <i>grep audio /proc/pci</i>
174</pre>
175
176
177<p>
178<warn>
179If you had a previous sound setup and there are still non-ALSA sound modules loaded, unload them <e>now</e>.
180Check with <c>lsmod</c> and use <c>rmmod</c> to unload all sound-related modules on your system.
181</warn>
182</p>
183
184<p>
185We could simply do an <c>emerge alsa-driver</c> now, this would compile and install <e>all</e> ALSA sound drivers.
186</p>
187<p>
188However, to save some time, lookup the <e>Module Name</e> of your soundcard(s) on the
189<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.
190Mine is <c>snd-emu10k1</c>, since I have an SBlive! soundcard, with the <e>EMU10K1</e> chipset.
191We'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.
192</p>
193
194<pre>
195# <i>env ALSA_CARDS='emu10k1' emerge alsa-driver</i>
196</pre>
197<note>
198You 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>.
199For example, like this: <c>echo 'ALSA_CARDS="emu10k1"' >> /etc/make.conf</c>
200</note>
201
202<note>
203When you want to install ALSA drivers for more than one soundcard, you could set ALSA_CARDS to a space-separated list
204of drivers; like this: <c>env ALSA_CARDS='emu10k1 intel8x0 ens1370' emerge alsa-driver</c>
205</note>
206
207<note>If you want to have OSS compatibility, make sure to emerge <i>alsa-oss</i>, it is the ALSA/OSS compatibility
208wrapper. </note>
209
210<note>If you plan on recompiling your kernels numerous times, it might
211be adviseable to emerge <c>alsa-driver</c> with <c>--buildpkg</c>. This
212will create a binary package for it. Later, after recompiling your kernel,
213you can just do <c>emerge --usepkg alsa-driver</c> which will install the
214binary package instead of recompiling it completely.</note>
215
216<p>
217After this, the ALSA modules should be installed on your system.
218</p>
219</body> 712<body>
220</section> 713
714<p>
715If your sound card lacks a hardware synthesizer, you could use a virtual one
716like <c>timidity++</c>. Installation is a breeze.
717</p>
718
719<pre caption="Installing timidity++">
720# <i>emerge timidity++</i>
721</pre>
722
723<p>
724For timidity to play sounds, it needs a sound font. If you do not have any,
725install <c>timidity-eawpatches</c> or <c>timidity-shompatches</c> which will
726give you some sound fonts. You can have multiple sound font configurations
727installed, and you can place your own in <path>/usr/share/timidity/</path>.
728To switch between different timidity configurations, you should use the
729<c>timidity-update</c> tool provided in the timidity++ package.
730</p>
731
732<pre caption="Installing sound fonts">
733# <i>emerge timidity-eawpatches</i>
734# <i>timidity-update -g -s eawpatches</i>
735
736<comment>(or)</comment>
737
738# <i>emerge timidity-shompatches</i>
739# <i>timidity-update -g -s shompatches</i>
740</pre>
741
742<p>
743Don't forget to add <c>timidity</c> to the default runlevel.
744</p>
745
746<pre caption="Adding timidity to the default runlevel">
747# <i>rc-update add timidity default</i>
748# <i>/etc/init.d/timidity start</i>
749</pre>
750
751<p>
752You can now try out <uri link="#doc_chap4_pre3">Playing MIDI</uri> files.
753</p>
754
755</body>
221<section> 756</section>
222 <title>Configuration of ALSA</title>
223<body>
224<p>
225Let's start configuring now to get ALSA working properly.
226We'll need to edit some files, to let our system know about the freshly installed ALSA modules.
227</p>
228
229<p>
230First, install <c>alsa-utils</c> on your system:
231</p>
232
233<pre caption = "Emerging alsa-utils">
234# <i>emerge alsa-utils</i>
235</pre>
236
237<p>
238Hereafter, we need to edit <path>/etc/modules.d/alsa</path>.
239</p>
240<warn>
241There is no need to edit <path>/etc/modules.conf</path>. Instead, always edit files in <path>/etc/modules.d</path>.
242</warn>
243<p>
244Check the ALSA portion <e>at the bottom of the file</e>.
245By tweaking this line you can specify the max number of soundcards you have (generally, just one).
246</p>
247<pre caption="At the bottom of /etc/modules.d/alsa">
248<comment>Set this to the correct number of cards.</comment>
249options snd cards_limit=1
250</pre>
251<p>
252Now we'll specify the sounddriver(s) ALSA should use. In the same file, edit like this:
253</p>
254<pre caption="In /etc/modules.d/alsa">
255## and then run `modules-update' command.
256## Read alsa-driver's INSTALL file in /usr/share/doc for more info.
257##
258## ALSA portion
259alias snd-card-0 snd-emu10k1
260<comment>## If you have more than one, add:</comment>
261## alias snd-card-1 snd-intel8x0
262## alias snd-card-2 snd-ens1370
263## OSS/Free portion
264## alias sound-slot-0 snd-card-0
265## alias sound-slot-1 snd-card-1
266##
267</pre>
268<note>
269If you have more than one soundcard, adjust the <c>cards_limit</c> value and add more snd-card aliases to the file.
270I don't have experience with this, but you can find examples for configurations with two or more soundcards in
271<uri link="http://www.alsa-project.org/alsa-doc/alsa-howto/c1660.htm">Chapter 6</uri>
272of the <uri link="http://www.alsa-project.org/alsa-doc/alsa-howto/alsa-howto.html">ALSA Howto</uri>.
273</note>
274<p>
275Last thing to do in this file, almost at the end, check if these lines are there and uncommented:
276</p>
277<pre caption="Near the end of /etc/modules.d/alsa">
278alias /dev/mixer snd-mixer-oss
279alias /dev/dsp snd-pcm-oss
280alias /dev/midi snd-seq-oss
281</pre>
282<p>
283Now double-check the file <path>/etc/modules.d/alsa</path> and when you're sure everyting is ok, run <c>modules-update</c>.
284<pre>
285# <i>modules-update</i>
286</pre>
287</p>
288<note>
289Running <c>modules-update</c> here will insert the data from <path>/etc/modules.d/alsa</path> into <path>/etc/modules.conf</path>
290</note>
291<p>
292You should also verify that /etc/devfsd.conf has the alsa devices and permissions correctly registered.
293</p>
294<pre caption="/etc/devfsd.conf">
295# ALSA/OSS stuff
296# Comment/change these if you want to change the permissions on
297# the audio devices
298LOOKUP snd MODLOAD ACTION snd
299LOOKUP dsp MODLOAD
300LOOKUP mixer MODLOAD
301LOOKUP midi MODLOAD
302REGISTER sound/.* PERMISSIONS root.audio 660
303REGISTER snd/.* PERMISSIONS root.audio 660
304</pre>
305<note>
306Notice 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.
307</note>
308</body>
309</section> 757<section>
310</chapter> 758<title>Tools and Firmware</title>
311<chapter> 759<body>
312<title>Starting ALSA</title> 760
761<p>
762Some specific sound cards can benefit from certain tools provided by the
763<c>alsa-tools</c> and <c>alsa-firmware</c> packages. If you need
764<c>alsa-tools</c>, be sure to define the ALSA_TOOLS variable in
765<path>/etc/make.conf</path> with the tools you require. For instance:
766</p>
767
768<pre caption="Selecting ALSA Tools in /etc/make.conf">
769ALSA_TOOLS="as10k1 ac3dec"
770</pre>
771
772<p>
773If the ALSA_TOOLS variable is not set, all available tools will be built.
774Now, install the <c>alsa-tools</c> (and/or <c>alsa-firmware</c>) package(s):
775</p>
776
777<pre caption="Installing ALSA Tools">
778# <i>emerge alsa-tools</i>
779</pre>
780
781</body>
313<section> 782</section>
314 <title>Adding alsasound to a runlevel</title>
315<body>
316<p>
317First thing to do now, is to make ALSA startup at boottime. Like this:
318<pre>
319# <i>rc-update add alsasound boot</i>
320</pre>
321</p>
322<p>
323<warn>Note that the alsasound script should be added to the "boot" runlevel, not the "default" runlevel.</warn>
324</p>
325</body>
326</section> 783<section>
784<title>A Big thank you to...</title>
785<body>
786
787<p>
788Everyone who contributed to the earlier version of the Gentoo ALSA Guide:
789Vincent Verleye, Grant Goodyear, Arcady Genkin, Jeremy Huddleston,
790John P. Davis, Sven Vermeulen, Benny Chuang, Tiemo Kieft and Erwin.
791</p>
792
793</body>
327<section> 794</section>
328 <title>Running and unmuting</title>
329<body>
330<p>
331Since we're Linux users, we don't want to reboot. So we'll start the alsasound script manually.
332</p>
333<pre>
334# <i>/etc/init.d/alsasound start</i>
335</pre>
336<p>
337ALSA is running now. If everything is ok, you should be able to see the ALSA modules loaded when running <c>lsmod</c>.
338However, sound won't work yet, because the channels are still muted. We need <c>amixer</c> for this.
339</p>
340<pre caption = "Running amixer">
341# <i>amixer</i>
342</pre>
343<p>
344<warn>
345You 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 modprobe
346<c>snd-mixer-oss</c> and <c>snd-pcm-oss</c> once. After that run amixer again.
347</warn>
348</p>
349<pre caption="only if you get an error when running amixer">
350# <i>modprobe snd-mixer-oss</i>
351# <i>modprobe snd-pcm-oss</i>
352# <i>amixer</i>
353</pre>
354<p>
355If you got this far, now unmute Master and PCM channels. Some hardware
356even requires you to unmute the center channel or even the surround
357channel.
358</p>
359<p>
360<pre caption = "Unmuting channels">
361# <i>amixer set Master 100 unmute</i>
362# <i>amixer set PCM 100 unmute</i>
363<comment>Only if the above doesn't succeed on its own:</comment>
364# <i>amixer set Center 100 unmute</i>
365# <i>amixer set Surround 100 unmute</i>
366<comment>Test the sound:</comment>
367# <i>aplay $KDEDIR/share/sounds/pop.wav</i> <codenote>(pop.wav is part of KDE)</codenote>
368</pre>
369</p>
370We check to see if sound is working by using the aplay (alsa play) command. If you hear a pop, then sound is indeed working.
371Then, adjust the volume settings to your liking; the ncurses-based <c>alsamixer</c> is a great way to get them "just so".
372<p>
373You may want to emerge <c>alsa-xmms</c> as that will provide ALSA support for XMMS.
374</p>
375When you reboot your system, the <e>alsasound</e> init script will properly save and restore your volume settings.
376</body>
377</section> 795<section>
378</chapter> 796<title>References</title>
379<chapter>
380<title>Final Notes</title>
381<section>
382 <title>After kernel-upgrades..</title>
383<body>
384<p>When you ever rebuild your kernel, or upgrade to another kernel, you'll have to rebuild the ALSA modules.</p>
385<p>Although you might have installed <c>alsa-driver</c>, <c>alsa-libs</c> and <c>alsa-utils</c>, only the first will
386have to be installed again, since it will put the alsa modules in
387<path>/lib/modules/*/kernel/sound/pci/</path>.</p>
388<pre caption="needed after each kernel compile">
389# <i>emerge alsa-driver</i>
390</pre>
391</body> 797<body>
392</section>
393<section>
394 <title>/etc/modules.autoload</title>
395<body>
396<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
397load the correct modules at startup.</p>
398<p>It's not necessary to add <c>snd-pcm-oss</c> or <c>snd-mixer-oss</c> in this file.
399Check the <uri link="http://www.djcj.org/LAU/guide/alsbook/faq1.html">this FAQ</uri> for more info.</p>
400</body>
401</section>
402
403<section>
404<title>Known bugs</title>
405<body>
406
407<note>
408This guide lags behind on the alsa-development. Chances are these bugs
409are already fixed when you read this.
410</note>
411 798
412<ul> 799<ul>
413<li> 800 <li><uri link="http://www.alsa-project.org/">The ALSA Project</uri></li>
414If you have <b>lots of noise</b> when using <b>oss</b> emulation, add 801 <li><uri link="http://linux-sound.org">Linux Sound/MIDI Software</uri></li>
415<e>options snd-pcm-oss dsp_map=1</e> to
416<path>/etc/modules.d/alsa</path>.
417</li>
418</ul> 802</ul>
419 803
420</body>
421</section>
422
423<section>
424 <title>More links..</title>
425<body>
426<p>
427You could check these for additional info:
428</p>
429<p>
430<ul>
431<li><uri link="http://www.gentoo.org/doc/en/desktop.xml">The Gentoo Linux Desktop Configuration Guide</uri></li>
432<li><uri link="http://www.alsa-project.org">ALSA Project Homepage</uri></li>
433<li><uri link="http://www.alsa-project.org/documentation.php3">ALSA Users Documentation</uri></li>
434<li><uri link="http://www.djcj.org">ALSA Howto's and FAQ's</uri></li>
435<li><uri link="http://tldp.org/HOWTO/Sound-HOWTO/index.html">Linux Sound HOWTO</uri></li>
436<li><uri link="http://linux-sound.org/">Sound and MIDI Software For Linux</uri></li>
437</ul>
438</p>
439</body> 804</body>
440</section> 805</section>
441</chapter> 806</chapter>
442</guide> 807</guide>

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