apm suspend breaks ALSA

apm suspend breaks ALSA

[Christopher Swingley]

Greetings,

I have a laptop with the es1978 ALSA sound driver built into the kernel.  
When I go through a suspend / resume cycle using apm, the sound system 
does not recover and loud static comes from the speakers instead of 
music / voice / etc.  On boot, ALSA works just fine.

One solution appears to be building ALSA as modules and unloading / 
reloading them, after a suspend / resume cycle.  With 2.4.xx and the OSS 
drivers built in, this wasn't an issue.

Now that I've got them built as modules and have a 'sound' script in 
/etc/apm/events.d/ that does the loading and unloading I'm happy, but I 
figured I'd report the issue anyway.

Chris
-- 
Christopher S. Swingley          email: cswingle@iarc.uaf.edu
IARC -- Frontier Program         Please use encryption.  GPG key at:
University of Alaska Fairbanks   www.frontier.iarc.uaf.edu/~cswingle/

Re: apm suspend breaks ALSA

[Takashi Iwai]

At Wed, 30 Jul 2003 07:12:19 -0800,
Christopher Swingley wrote:
> 
> Greetings,
> 
> I have a laptop with the es1978 ALSA sound driver built into the kernel.  
> When I go through a suspend / resume cycle using apm, the sound system 
> does not recover and loud static comes from the speakers instead of 
> music / voice / etc.  On boot, ALSA works just fine.
> 
> One solution appears to be building ALSA as modules and unloading / 
> reloading them, after a suspend / resume cycle.  With 2.4.xx and the OSS 
> drivers built in, this wasn't an issue.
> 
> Now that I've got them built as modules and have a 'sound' script in 
> /etc/apm/events.d/ that does the loading and unloading I'm happy, but I 
> figured I'd report the issue anyway.

as default, the power-management of es1968 is enabled only on a
certain board, namely,
	ESS1978 _and_ (vendor == 0x1028 || vendor == 0x1179)

first, please check whether your pci id matches with it.

the behavior can be changed by a module option, use_pm, but it's
missing in the kernel boot parameter (i'll fix this later).
in that case, modify use_pm[] default value from 2 to 1, to force to
use power-management.


Takashi