Hi Takashi, >-----Original Message----- >From: Takashi Iwai [mailto:tiwai@xxxxxxx] >Sent: Tuesday, March 26, 2019 4:54 PM >To: Yang, Libin <libin.yang@xxxxxxxxx> >Cc: alsa-devel@xxxxxxxxxxxxxxxx; broonie@xxxxxxxxxx >Subject: Re: [PATCH V2] ASoC: fix hdmi codec driver contest in S3 > >On Tue, 26 Mar 2019 09:46:31 +0100, >Yang, Libin wrote: >> >> 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: 1. Component suspend is called. It will call snd_hdac_display_power() to turn off the display power. 2. runtime suspend is called. It will operate on the registers. This is wrong. We can't operate on registers when the power is off. So I think we can only call snd_hdac_display_power() either in component suspend/resume or runtime suspend/resume. We can't call snd_hdac_display_power() in both. And based on the previous test, component suspend/resume will not be called when playback. So we can only call snd_hdac_display_power() in runtime suspend/resume? Regards, Libin > >Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
