[alsa-devel] module snd-atiixp issue with suspend/hibernate/resume

[Ryan Dunn]

Thanks Takashi,

I did a bit more testing last night.  The LED does work after a reboot (I
don't know what I was doing that I thought it didn't).  It also retains
state after a reboot if I muted it before the reboot.  One thing I noticed,
if I have it muted when I suspend, on resume, it looks like the mute led
flashes back on for a split second, then turns off.  Maybe the resume code
is overwriting the register?  I'll start digging through that code tonight.

Ryan

On Thu, Apr 30, 2009 at 1:53 AM, Takashi Iwai <tiwai at suse.de> wrote:

> At Thu, 30 Apr 2009 00:43:02 -0400,
> Ryan Dunn wrote:
> >
> > Thanks Lee,
> >
> > I grabbed the kernel source from the repos and started perusing the
> code.  It
> > looks like when the module is installed, the call chain starts in
> atiixp.c and
> > moves into ac97/ac97_codec.c via a call to snd_ac97_tune_hardware() which
> > ultimately twiddles a bit in the AC97_POWERDOWN register.  I'm not sure
> yet if
> > the suspend method properly saves this register on suspend or not;
>
> It should.  snd_ac97_resume() writes the cached value.
> Check /proc/asound/card0/codec97#0/ac97#*+regs files before and after
> suspend.  You can change the codec register value directly via proc
> file, e.g.
>    # echo 0x12 0x1234 > /proc/asound/card0/codec97#0/ac97#0-0+regs
> (only when you build with the debug option).
>
> The bit 0x8000 of the power-down register should correspond to LED.
>
>
> Takashi
>
> > or if the
> > same call chain needs to be repeated on a resume.  I appreciate your
> quick and
> > relevant answer.  When I get time, I'll start adding some debug printouts
> to
> > try this out.
> >
> > Also, the struct ac97_quirk ac97_quirks[] array has a couple of entries
> in it
> > currently (in the atiixp.c file).  How do I get the subvender/subdevice
> id's
> > for my system (I didn't seem to have luck with lspci, unless I'm not
> looking
> > in the right fields)?  Would it be possible to edit the driver so that an
> > explict module option would not be needed on my hardware?
> >
> > Thanks,
> > Ryan
> >
> > On Wed, Apr 29, 2009 at 10:42 PM, Lee Revell <rlrevell at joe-job.com>
> wrote:
> >
> >     On Wed, Apr 29, 2009 at 12:06 AM, Ryan Dunn <oryandunn.ml at gmail.com>
> >     wrote:
> >     > I have a Compaq V2000 laptop with the ATI IXP chipset and make use
> of
> >     the
> >     > snd-atiixp module.  The laptop needs to have the ac97_quirk option
> set
> >     to 7
> >     > to enable the mute LED.  After setting this option in the
> >     > /etc/modprobe.d/options.conf file, the mute LED works after a
> reboot.
> >     > However, after a resume from suspend or hibernate, the mute LED
> does not
> >     > work.  The alsa-info.sh script reports that the quirk is still set
> with
> >     7.
> >     > At this point a reboot will NOT fix the problem.  The only way to
> fix it
> >     is
> >     > to remove and reinsert the module with modprobe.
> >     >
> >     > This is on a fresh Ubuntu 9.04 install.  Any ideas?  I wasn't sure
> if
> >     this
> >     > should be reported here or on the kernel list.  I saw a similar
> issue
> >     with
> >     > the ac97_quirk on the kernel list and they were referred here.  I'm
> a
> >     > software developer, so I'd be willing to try ideas/possible
> solutions if
> >     you
> >     > have them.
> >
> >     Get the Ubuntu source code for the package that owns that ALSA
> driver,
> >     find the place in the driver's initialization code where ac97_quirk=7
> >     is handled, then check the driver's suspend and resume callbacks and
> >     make sure the suspend callback is correctly saving the LED state and
> >     that the resume callback is re-initializing the LED from the saved
> >     state in the same way the init code does.  grep and printk() are your
> >     friends ;-)
> >
> >     HTH,
> >
> >     Lee
> >
> >
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel at alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
>