Configuring ALSA in YDL4

[Joseph E. Sacco, Ph.D.]

I have made "some progress" getting ALSA to "work".

By "some progress" and "work" I mean:

(0) Sound Card detection works using whatever sound driver it uses
[OSS maybe???]

(1) xmms-1.2.10-1 works with the ALSA sound driver [and others]
[using source downloaded from http://www.xmms.org]

Note: I set buffertime = 3000ms, periodtime = 500ms to improve sound
      quality.

(2) MOL-0.9.71 audio works with the ALSA sound driver

(3) gnome-cd, kscd, and grip are still *SILENT*.


What I did:
(0) Built and installed some additional kernel modules
(1) edited /etc/modprobe.conf


Discussion:

Kernel Modules
---------------
ALSA driver support is now distributed with the linux-2.6.x kernel. The
YDL kernel configurations configure a limited number of ALSA modules:

        #
        # Advanced Linux Sound Architecture
        #
        CONFIG_SND=m
        CONFIG_SND_TIMER=m
        CONFIG_SND_PCM=m
                         ...


I added others to the configuration:

        #
        # Advanced Linux Sound Architecture
        #
        CONFIG_SND=m
        CONFIG_SND_TIMER=m
        CONFIG_SND_PCM=m
        
        CONFIG_SND_RAWMIDI=m
        CONFIG_SND_SEQUENCER=m
        # CONFIG_SND_SEQ_DUMMY is not set
        CONFIG_SND_OSSEMUL=y
        CONFIG_SND_MIXER_OSS=m
        CONFIG_SND_PCM_OSS=m
        CONFIG_SND_SEQUENCER_OSS=y
        # CONFIG_SND_VERBOSE_PRINTK is not set
        # CONFIG_SND_DEBUG is not set


rebuilt and installed the modules. I doubt that all of these are needed,
although some are. It would be nice to know which ones are really
necessary.


modprobe.conf
-------------
I started out with /etc/modprobe.conf.dist and made a few additions:

# ALSA portion
alias char-major-116-* snd
alias snd-card-0 snd-powermac
                                                                                                
# OSS/Free portion
alias char-major-14* soundcore
alias sound-slot-0 snd-powermac
                                                                                           #
alias sound-service-*-0 snd-mixer-oss
alias sound-service-*-1 snd-seq-oss
alias sound-service-*-3 snd-pcm-oss
alias sound-service-*-8 snd-seq-oss
alias sound-service-*-12 snd-pcm-oss
                                                                                                
# Module install and remove rules             
install snd-card-0 /sbin/modprobe --ignore-install snd-card-0 && {
/usr/sbin/alsactl restore >/dev/null 2>&1 || :; }
remove snd-card-0 { /usr/sbin/alsactl store >/dev/null 2>&1 || :; };
/sbin/modprobe -r --ignore-remove
                                                                                                
install sound-slot-0 /sbin/modprobe --ignore-install sound-slot-0 && {
/bin/aumix-minimal -f /etc/.aumixrc -L >/dev/null 2>&1 || :; }
remove sound-slot-0 { /bin/aumix-minimal -f /etc/.aumixrc -S >>/dev/null
2>&1 || :; }; /sbin/modprobe -r --ignore-remove


The "module install and remove rules" [which I found on the web in
several fedora discussions] insure that configuration information is
restored during module installation and saved during module removal. 
Without these entries you have to reset all the levels each time you
reboot. Are these rules *the* rules? Don't know. They seem to work.

It would be nice if "we" could get the other CD players to work. They
behave as if something has been muted. But... xmms works so I don't know
what that "something" might be. Thoughts???


-Joseph


-- 
Joseph E. Sacco, Ph.D. <joseph_sacco at comcast.net>