[alsa-devel] Scarlett 18i8 hardware out of sync with AlsaMixer

[Takashi Iwai]

[Added more people to Cc]

At Wed, 27 May 2015 08:55:21 -0400,
Adam Goode wrote:
> 
> The settings were not reset across a mem sleep (echo mem > /sys/power/state).
> 
> Hard power off / power on does make the settings get out of sync.

Then maybe the problem is that the device keeps the old setting while
the driver resets to the default.  I vaguely remember that scarlett
could save the default state in a persistent area, and the original
driver patch had a kctl to trigger it.  We didn't take it because it
might be dangerous.


Takashi


> Adam
> 
> 
> On Wed, May 27, 2015 at 2:43 AM, Takashi Iwai <tiwai at suse.de> wrote:
> > At Tue, 26 May 2015 21:39:22 -0400,
> > Adam Goode wrote:
> >>
> >> Linux 4.0.2-300.fc22.x86_64
> >>
> >> Hi,
> >>
> >> I have the Scarlett 18i8 USB device that is supported by the new
> >> scarlett_mixer.c code. I am happy to say that the mixer code works in
> >> most cases. But under some conditions, I cannot get any sound out of
> >> the device until I go and toggle the "Matrix 01 Input" and "Matrix 02
> >> Input" enums up and then down (from PCM 1 and PCM 2). This appears to
> >> me to be some kind of cache invalidation bug, where the device is out
> >> of sync with kernel mixer state.
> >>
> >> I will take a look at the code myself at some point, but not for a
> >> while. But I am happy to try patches if anyone comes up with anything
> >> in the mean time.
> >
> > Does it happen after some S3/S4 or even during a normal operation
> > without power-saving?  The USB-audio device supports autopm, so this
> > needs to be checked, too.
> >
> >
> > Takashi
>