[alsa-devel] HD-audio runtime PM

[Lin, Mengdong]

> -----Original Message-----
> From: Takashi Iwai [mailto:tiwai at suse.de]
> Sent: Wednesday, November 27, 2013 6:55 PM
> To: Lin, Mengdong
> Cc: Wang Xingchao; Alsa-devel at alsa-project.org; David Henningsson
> Subject: Re: [alsa-devel] HD-audio runtime PM
> 
> At Wed, 27 Nov 2013 09:37:17 +0000,
> Lin, Mengdong wrote:
> >
> > > -----Original Message-----
> > > From: Takashi Iwai [mailto:tiwai at suse.de]
> > > Sent: Tuesday, November 26, 2013 4:26 PM
> >
> > > > > > -----Original Message-----
> > > > > > From: Takashi Iwai [mailto:tiwai at suse.de]
> > > > > > Sent: Tuesday, November 26, 2013 2:14 PM
> > > > > > To: Wang Xingchao
> > > > >
> > > > > > > I test WAKEEN feature on Haswell machines before, it could
> > > > > > > really wakeup system from D3.
> > > > > >
> > > > > > But the runtime suspend doesn't power down to D3 by itself.
> > > > > > Did you test really with D3?
> > > > >
> > > > > I will double check this on Haswell with sound git tree for-linus
> branch.
> > > > > We've tried Android on Haswell-ULT last week, the display HD-A
> > > controller can enter D3 and HDMI cable plug-in can wake up the
> > > controller and codec. The code base is v3.9 with various driver patches.
> > > >
> > > > Hrm, but as I mentioned, we have no D3 call in runtime suspend
> > > > callback.  How does it reach to D3 then?  Maybe that part is
> > > > patched in your side?
> >
> > Hi,
> >
> > I've checked two Haswell-ULT platforms with sound git tree for-linus
> branch, under Ubuntu:
> > - ELD cannot refresh properly.
> > - HDMI hot-plug cannot wake up the audio controller.
> >
> > The controller is suspended when idle timeout and put in D3 by PCI
> driver. Here is the status shown by lspci -vvvv as root:
> > 00:03.0 Audio device: Intel Corporation Device 0a0c (rev 09)
> > 	Capabilities: [50] Power Management version 2
> > 		Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
> PME(D0-,D1-,D2-,D3hot-,D3cold-)
> > 		Status: D3 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- ...
> Status:
> > D3 mean the device is in D3.
> >
> > I guess maybe the latest display driver does not handle hot-plug
> properly which affect both ELD and device wakeup.
> >
> > For Android on Haswell, the kernel code base and BIOS are different.
> >
> > I'll further check this issue. Is it very urgent?
> 
> Not that urgent, but if it's a regression, we must fix it.
> If it's no regression, the urgency decreases, of course.
> 
> > I cannot work full time on this now due to some timing optimization
> task for Baytrail at the same time.
> 
> At least, it'd be helpful if you can confirm whether it still works with
> vanilla 3.9.x kernel (or whatever version) you tested in the past -- i.e. to
> know whether it's a regression or not.

Okay, I'll try kernels close to when Xingchao enable this wake-up feature.

Thanks
Mengdong