[Intel-gfx] [PATCH] drm/i915: Acquire audio powerwell for HD-Audio registers

[Takashi Iwai]

On Thu, 04 Aug 2016 18:44:11 +0200,
Daniel Vetter wrote:
> 
> On Wed, Aug 03, 2016 at 05:09:00PM +0100, Chris Wilson wrote:
> > On Haswell/Broadwell, the HD-Audio block is inside the HDMI/display
> > power well and so the sna-hda audio codec acquires the display power
> > well while it is operational. However, Skylake separates the powerwells
> > again, but yet we still need the audio powerwell to setup the registers.
> > (But then the hardware uses those registers even while powered off???)
> 
> Yeah feels fishy, but will at least duct-tape over the breakage from the
> audio side. Most likely the reg writes go exactly nowhere and there's a
> bug on the audio side. And this patch doesn't fix that.

Well, if the relevant code paths are only over these callbacks, I
guess the following fix would work instead.

Can anyone check?


Takashi

---
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 89dacf9b4e6c..88ad391452ae 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -1021,8 +1021,8 @@ static int azx_runtime_resume(struct device *dev)
 			snd_hdac_i915_set_bclk(bus);
 		} else {
 			/* toggle codec wakeup bit for STATESTS read */
-			snd_hdac_set_codec_wakeup(bus, true);
-			snd_hdac_set_codec_wakeup(bus, false);
+			snd_hdac_display_power(bus, true);
+			snd_hdac_display_power(bus, false);
 		}
 	}