[alsa-devel] via_dmapos_patch

[Takashi Iwai]

At Thu, 30 Sep 2010 10:39:30 +0200,
David Henningsson wrote:
> 
> On 2010-09-30 08:58, Takashi Iwai wrote:
> > At Wed, 29 Sep 2010 10:14:49 +0200,
> > David Henningsson wrote:
> >>
> >> I'm researching a few bugs where the user claims position_fix=1 helps
> >> the problem, but adding the quirk for that model surprisingly didn't. So
> >> looking at the code, I concluded that the difference was
> >> via_dmapos_patch, and that they all had via_dmapos_patch=1, and that
> >> via_dmapos_patch=0 helped them solve the problem. Three out of five (not
> >> all of them have reported back on via_dmapos_patch=0 yet) are VIA
> >> controllers rev 10.
> >>
> >> So we now have VIA controllers that need via_dmapos_patch=0.
> 
> I'm cc:ing Joseph here. You were the one writing via_dmapos_patch 
> originally, could you confirm the suspicion that VIA controller rev 10 
> (and possibly more) actually should have via_dmapos_patch turned off?
> 
> >>
> >> I can think of a few approaches here:
> >>
> >> 1) since position_fix=1 implicitly sets via_dmapos_patch to 0 (maybe
> >> unintentionally), we should add a position_fix=3 meaning lpib +
> >> via_dmapos_patch=1
> >>
> >> 2) figure if something has changed recently (as in "within the last
> >> year"...) that has made via_dmapos_patch=1 work worse than before
> >>
> >> 3) figure out if there are several ATI/VIA controllers that actually
> >> never wants the patch.
> >>
> >> Any thoughts?
> >
> > All sound as reasonable proposals.
> > The 1 is easy.  David, could you care to send a patch?'
> 
> Something like this (untested)?

Looks good.  Applied now.


thanks,

Takashi