Hi Takashi,
In the case of legacy HD-audio, we "fixed" the problem by avoiding the trigger of async work at resume, but let it be triggered from runtime resume. In ASoC case, however, it's no option.
Maybe a possible solution in the sound driver side would be to move from system suspend/resume to ASoC component
suspend/resume.
The runtime suspend/resume can be kept as is, and call pm_runtime_force_suspend and resume from the component
suspend/resume
callbacks. Since the component callbacks are certainly processed before DAPM events, this should assure the order.
I tried to move display power setting from runtime suspend/resume to component suspend/resume. I found there may be another issue: playback will NOT call component suspend/resume. This means we will never have chance to set the display power if we don't do the S3.
The runtime suspend/resume are fine and need to be kept, I suppose. The only problem is the system suspend/resume callbacks that call pm_runtime_force_*(). Just moving these two to component would work?
Let's see the flow of the suspend:
- Component suspend is called. It will call snd_hdac_display_power()
to turn off the display power.
No, what I meant was to make the component suspend calling pm_runtime_force_suspend() instead of the system suspend. Ditto for the component resume calling pm_runtime_force_resume().
It seems this component suspend/resume method works well. I will do more test and send out the patch later.
Regards, Libin
Takashi