[alsa-devel] [REGRESSION] Headphones no longer working on MacPro6, 1 with 4.4

[Takashi Iwai]

On Tue, 15 Mar 2016 20:38:41 +0100,
Takashi Iwai wrote:
> 
> On Tue, 15 Mar 2016 20:23:09 +0100,
> Laura Abbott wrote:
> > 
> > Hi,
> > 
> > We received a bug report https://bugzilla.redhat.com/show_bug.cgi?id=1316119
> > that the headphone jack on a MacPro6,1 stopped working on an upgrade from 4.3
> > to 4.4.
> > 
> > The bugzilla has the alsainfo, diffing shows that the Amp-Out vals are
> > different. I tried a revert of 9f660a1c4 (" ALSA: hda/realtek - Fix silent
> > headphone output on MacPro 4,1 (v2)") but that didn't help.
> > 
> > Any ideas before asking for a bisect? Does this hardware version need to have
> > the vref fixup as well?
> 
> The obvious difference is the power state of each node.  The recent
> kernel has the finer power saving mode, and this might be the cause --
> Mac has some secret that requires some node to be powered up.
> 
> Try to power on each node via hda-verb.  For example, to power up the
> node 0x05, run like:
>   hda-verb /dev/snd/hwC0D0 0x05 SET_POWER 0x01

Oops, a typo: the last argument must be 0x00, corresponding to D0:
    hda-verb /dev/snd/hwC0D0 0x05 SET_POWER 0x00


Takashi