PPC: 7.1: ALSA-Sound on PPC

Support knowledgebase (ppc_alsasound)
Applies to

SuSE Linux PowerPC: Version 7.1

Symptom:

You want to configure the sound under SuSE Linux 7.1 PPC on a Powermac, but however encounter some inconsistencies.

Cause:

Since the version 7.1 we use ALSA for the sound support. Thus some well-known methods became obsolet. In addition the configuration of ALSA yet isn't tuned for PowerMacs in all details.

Solution 1:

In Yast2 open the sound module. Go through the menus as indicated. If you should not hear sound with the test, continue nevertheless. The reason can be situated in the fact that there are internal speakers in the Macs. In the intel world this is not so well-known. Yast2 or ALSA therefore adjust partial false "channels", e.g. the external speaker is set active instead of the internal, although no external speaker is attached. Quit Yast2 and open a mixer, e.g. Soundmixer. It happens that the internal speaker is to be regulated over the controller for LineIn (!). Give it a try to find the correct adjustments.

Solution 2:

If, out of any reason ALSA doesn't work for you, there still remains the possibility of implementing sound over the dmasound kernelmodule. In that case load the module as root with these commands:

with Kernel 2.2.18

         modprobe dmasound

with Kernel 2.4.2

         modprobe dmasound_pmac

Additional note

If for any reason you want to try out both solutions, note please that no "foreign" modules are loaded at each case. To control which moduls are loaded you can use the instruction lsmod . E.g. loaded dmasound modules look like that:

Module                  Size  Used by
snd                    54752   0  (autoclean)
dmasound_pmac          25872   1
dmasound_core          11392   1  [dmasound_pmac]
soundcore               4624   3  [snd dmasound_core]

Loaded ALSA-modules look as follows:

Module                  Size  Used by
snd-pcm-oss            24032   1 (autoclean)
snd-pcm-plugin         18320   0 (autoclean) [snd-pcm-oss]
snd-mixer-oss           6160   0 (autoclean) [snd-pcm-oss]
snd-card-awacs         26864   1
snd-pcm                47632   0 [snd-pcm-oss snd-pcm-plugin
snd-card-awacs]
snd-timer              14880   0 [snd-pcm]
snd-mixer              34784   0 [snd-mixer-oss snd-card-awacs]
snd                    54752   1 [snd-pcm-oss snd-pcm-plugin
snd-mixer-oss snd-card-awacs snd-pcm snd-timer snd-mixer]
soundcore               4624   2 [snd]

In order to unload modules execute the following instructions:

For ALSA modules:

rcalsa stop

For dmasound modules:

rmmod snd dmasound_pmac dmasound_core sound core

Keywords: PPC, SOUND, ALSA, DMASOUND, IMAC, POWERMAC

Categories: Power PC

SDB-ppc_alsasound, Copyright SuSE Linux AG, Nürnberg, Germany - Version: 12. Jun 2001
SuSE Linux AG - Last generated: 14. Aug 2001 by rschmid (sdb_gen 1.40.0)