[alsa-devel] [regression] probably in mixer.c code

[Takashi Iwai]

At Tue, 08 Nov 2011 12:25:06 +0100,
Alexey Fisher wrote:
> 
> Am 08.11.2011 10:59, schrieb Takashi Iwai:
> > At Tue, 08 Nov 2011 09:49:13 +0100,
> > Alexey Fisher wrote:
> >>
> >> Hallo all, Takashi,
> >>
> >> there is one regression in current linux main tree:
> >>
> >> cval->res quirks do not work any more. See usb/mixer.c:1150
> >> Are there was some work in this area or may be some one bisected this
> >> bug down?
> >
> > Are you referring to the device 046d:09a4, which sets the mixer range
> > manually?  If yes, does the patch below work?
> >
> 
> 
> No, i referring to devices 046d:0991, 046d:081d, i don't have access to 
> 046d:09a4.
> 
> This part is broken for me:
>          case USB_ID(0x046d, 0x0991):
>          /* Most audio usb devices lie about volume resolution.
>           * Most Logitech webcams have res = 384.
>           * Proboly there is some logitech magic behind this number --fishor
>           */
>                  if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
>                          snd_printk(KERN_INFO
>                                  "set resolution quirk: cval->res = 384\n");
>                          cval->res = 384;
>                  }
>                  break;

OK, so _what_ is actually broken?  Do you see the message but
cval->res is overridden later?


Takashi