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Re: alsa not working



On Saturday 12 June 2004 01:05, Chris Metzler wrote:
> On Fri, 11 Jun 2004 23:42:52 +0200
>
> John van Spaandonk <j.spaandonk@chello.nl> wrote:
> > On Friday 11 June 2004 22:06, Chris Metzler wrote:
> >> Your problem is that you are loading OSS modules.  The ALSA modules
> >> can't load if the OSS modules are installed.  First, remove the OSS
> >> modules from your /etc/modules file, so they'll stop being loaded
> >> automatically during boot.  Then, check to see if you have either
> >> discover or hotplug installed.  During boot, their scripts run before
> >> the ALSA script does, and they'll try to install OSS modules.  If
> >> you have either or both of them installed, make sure that the OSS
> >> modules are blacklisted in their respective configuration files.
> >> The ALSA modules will load appropriately.
> >
> > Chris, thanks for this tip.
> > It seems a very reasonable hypothesis.
> >
> > One question: how do I recognise OSS modules?
> > Did you see any in my lsmod output?
>
> Yes.  From your lsmod output:
>
> }Module                  Size  Used by    Not tainted
> 			[ snip ]
> } mpu401                 21092   0 (unused)
>
> OSS module to handle the external MIDI port.
>
> } emu10k1                64780   2
>
> OSS module to handle the audio controller on your soundcard.
>
> } sound                  61984   0 [mpu401 emu10k1]
>
> Top-level OSS module.
>
> } soundcore               4420   7 [emu10k1 sound]
>
> Module that provides sound capabilities to the kernel.  You need
> this one regardless of whether you're using OSS or ALSA.
>
> } ac97_codec             13784   0 [emu10k1]
>
> OSS module to handle the AC97 codec (mixer, DAC/ADC, etc.) on
> your soundcard.
>
> ALSA modules have "snd_" at the beginning.  Someone who has
> a Soundblaster Live will have sound modules that look like
> this (sorted):
>
> } snd                    33796   0 [snd-seq-midi snd-emux-synth
> snd-seq-virmidi snd-seq-oss snd-seq-midi-event snd-seq snd-pcm-oss
> snd-mixer-oss snd-emu10k1 snd-pcm snd-timer snd-hwdep snd-util-mem
> snd-ac97-codec snd-rawmidi snd-seq-device] } snd-ac97-codec         48300  
> 0 [snd-emu10k1]
> } snd-emu10k1            75332   1 [snd-emu10k1-synth]
> } snd-emu10k1-synth       4860   0 (autoclean) (unused)
> } snd-emux-synth         28348   0 (autoclean) [snd-emu10k1-synth]
> } snd-hwdep               5248   0 [snd-emu10k1]
> } snd-mixer-oss          13104   1 [snd-pcm-oss]
> } snd-page-alloc          6228   0 [snd-emu10k1 snd-pcm]
> } snd-pcm                61892   0 [snd-pcm-oss snd-emu10k1]
> } snd-pcm-oss            37956   0
> } snd-rawmidi            14240   0 [snd-seq-midi snd-seq-virmidi
> snd-emu10k1] } snd-seq                38448   2 [snd-seq-midi
> snd-emux-synth snd-seq-midi-emul snd-seq-virmidi snd-seq-oss
> snd-seq-midi-event] } snd-seq-device          4256   0 [snd-seq-midi
> snd-emu10k1-synth snd-emux-synth snd-seq-oss snd-seq snd-emu10k1
> snd-rawmidi] } snd-seq-midi            4000   0 (autoclean) (unused)
> } snd-seq-midi-emul       4944   0 (autoclean) [snd-emux-synth]
> } snd-seq-midi-event      3584   0 [snd-seq-midi snd-seq-virmidi
> snd-seq-oss] } snd-seq-oss            29632   0 (unused)
> } snd-seq-virmidi         3320   0 (autoclean) [snd-emux-synth]
> } snd-timer              15588   0 [snd-seq snd-pcm]
> } snd-util-mem            1280   0 [snd-emux-synth snd-emu10k1]
>
> (I compile soundcore into my kernel rather than use it as a module,
> which is why it's not listed here as well).
>
> > BTW I had installed discover just tonight, to see if it would help;
> > obviously I'm better of without it if I want to use ALSA.
>
> Well, I have it installed; you just need to configure it to not load
> the OSS modules, which is very straightforward.  Look at the man
> pages for discover, discover-modprobe, and discover-modprobe.conf.
>
> > I also use hotplug, which gives me lots of error messages but seems
> > to work with USB anyway. It says PCI events are not synthesised, so I
> > guess I do not really have to worry about hotplug for the sound card?
>
> I dunno.  I don't really understand hotplug myself.  I've just heard
> other people here (typically, people with 2.6 kernels) talk about having
> to make sure hotplug didn't load OSS modules.
>
> > On a related note, isn't it time for the discover program to start
> > installing ALSA over OSS? Or does Debian use ALSA as a default only for
> > the 2.6 kernel?
>
> It's not Debian, but rather the kernel folks, who indicated that OSS
> was the default sound infrastructure up through the 2.4 kernels, and
> ALSA starting with 2.6.  But I agree that discover either ought to
> favor the ALSA modules if they're present too, or should ask about it
> in its initial configuration (and maybe that's something that could
> be implemented through debconf, dunno).
>
> -c
Chris,

Again many thanks for this wonderful information.
Now I understand what's happening.

The only thing to remain is to actually find the alsa modules.
They do not appear to be included with the kernel image (OSS modules are).

I could not find a package with alsa modules for the latest 2.4.26 kernel
(only for 2.4.25).
Am I correct in assuming that I must either compile these modules from the
alsa source  or go back to the older kernel?

Regards,

John



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