Re: [REGRESSION] Audient EVO4 hardware volume control now requires quirk

[Takashi Iwai <tiwai@suse.de>]

On Tue, 29 Sep 2026 14:38:03 +0200,
Takashi Iwai wrote:
> 
> On Tue, 29 Sep 2026 07:58:03 +0200,
> Takashi Iwai wrote:
> > 
> > On Tue, 29 Sep 2026 00:39:05 +0200,
> > Sasha Levin wrote:
> > > 
> > > > [   80.940668] usb 3-1: cannot set ctl value: req = 0x1, wValue = 0x203,
> > > > wIndex = 0xa00, type = 4, data = 0x0/0x81
> > > [...]
> > > > numid=4,iface=MIXER,name='EVO4  Playback Volume'
> > > >    ; type=INTEGER,access=rw---R--,values=4,min=0,max=254,step=0
> > > >    : values=182,182,0,0
> > > 
> > > Thanks, that narrows it down.
> > > 
> > > Every failure is SET_CUR of the Volume control on feature unit 10, channel 3
> > > (wValue 0x0203, wIndex 0x0a00). That unit is 'EVO4  Playback Volume' and
> > > advertises read/write volume on all four channels. mixer_ctl_feature_put()
> > > writes channels 1 and 2, then returns the channel 3 error, so the hardware
> > > volume changes while userspace is told the write failed and adds software
> > > attenuation on top. Faaris sees the same on 7.3-rc5, so this is a mainline
> > > regression from 87a6f2fa6e6c ("ALSA: usb-audio: Propagate write errors in
> > > generic mixer put callbacks").
> > 
> > Right.  So a simple fix would be to just to set the IGNORE_CTL_ERROR
> > quirk flag like below.  One of iD14 models has already this flag, so
> > it might be safer to set to all Audient devices.
> 
> ... and below is such a version to cover all Audient devices:
> 
> Faaris, please let us know if this (or previous) one actually works
> for you.  Once after confirmation, I'll submit the proper patch for
> upstream.

... or if you have a chance to test Christian's patch set and verify
whether the problem is fixed there, we can avoid other changes:
  https://lore.kernel.org/20260919151840.24371-1-arc@gmx.li


Takashi