[Intel-gfx] [PATCH] snd/hda: Balance hda->need_i915_power across runtime_suspend

[Chris Wilson]

Quoting Takashi Iwai (2019-04-09 22:35:28)
> On Tue, 09 Apr 2019 23:27:41 +0200,
> Chris Wilson wrote:
> > 
> > In runtime_resume, we release the local display_power wakeref if we can
> > rely on i915 providing a wakeref along the component. On suspend
> > therefore, we should only release the display_power if we kept it from
> > runtime_resume.
> 
> Hrm, it shouldn't matter.  After the recent code rewrite, the control
> isn't refcount any longer, hence it's fine to call
> display_power(false) again even if it were already powered off.

That is the puzzle. Have a look at the glk-dsi results,
https://patchwork.freedesktop.org/series/59253/
something does appear to go wrong in azx_probe_continue (and seems to be
avoided by this patch).

Perhaps something like https://patchwork.freedesktop.org/patch/297656/?series=59257&rev=1
if the pm_runtime_autosuspend is occurring from a workqueue at the same
time as we call display_power(false).
-Chris