i was getting those overrun issue because of one controller bug, if i write zero to TXCR/RXCR register to disable both transmit and receive logic before low power mode then i am getting this overrun error after resume. Thanks a lot for your help Thanks Nobin Mathew On 5/28/07, Nobin Mathew <nobin.mathew@xxxxxxxxx> wrote: > I think i found the issue. Issue is in controller. Soon i will get > back with more details > > > > On 5/28/07, Nobin Mathew <nobin.mathew@xxxxxxxxx> wrote: > > I did some more investigation into this issue. > > > > There are two cases, in the first case it is working after resume() > > and in the second case it is not working after resume > > > > 1st Case: > > > > 1) boot the system > > 2)Load sound modules > > 2)mixer setting (alsactl restore 0) > > 3)Do power managemnt (sleep) suspend() > > 4)Come out of suspend, resume() > > 5) > > sound is coming out in this case > > > > 2nd Case: > > 1)boot the system > > 2)load sound modules > > 3)mixer settings (alsactl restore 0) > > 4)Do playback aplay -M /usr/share/sounds/alsa/Side_Right.wav > > 5) Let aplay to completion and kill all alsa apps if any running. > > 6)Do power managemnt (sleep) suspend() > > 7)Come out of suspend, resume() > > 8)Do playback aplay -M /usr/share/sounds/alsa/Side_Right.wav > > > > in this case no sound is coming out and i am getting underrun error. > > > > > > I am attaching some logs, these are the ac97 codec register values at > > various stages. > > > > Mainly look at the register 3c. > > > > > > > > > > > > > > > > > > > > > > > > > > On 5/25/07, Takashi Iwai <tiwai@xxxxxxx> wrote: > > > At Fri, 25 May 2007 13:39:40 +0100, > > > Liam Girdwood wrote: > > > > > > > > On Fri, 2007-05-25 at 17:34 +0530, Nobin Mathew wrote: > > > > > Every ALSA driver is calling these for suspend > > > > > > > > > > snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); > > > > > snd_pcm_suspend_all(pcm[i]); > > > > > > > > > > And for resume > > > > > snd_power_change_state(card, SNDRV_CTL_POWER_D0) > > > > > > > > > > > > > > > In ALSA ASoC no driver is calling any of this, even not in soc-core.c > > > > > > > > > > My driver is an ASoC driver and I am also not calling these functions > > > > > > > > > > Will this cause any Issue? > > > > > > > > > > > > > These should probably be called to inform the upper layers of the PM > > > > state. Can you log a bug for this in ALSA bugzilla. > > > > > > > > Fwiw, this _shouldn't_ effect your resume. You should still see calls to > > > > trigger for your DMA / AC97 to re-start transmission of PCM data. > > > > > > I think this does matter. Without calling snd_pcm_suspend*(), the > > > stream is assumed to be still active, thus eventually neither prepare > > > nor trigger is called at resume. If the hardware is perfectly > > > resumed as it was before suspend, it may still work somehow. > > > > > > However, usually it's impossible to resume the hardware perfectly. > > > Thus, we need one stop the stream via snd_pcm_suspend*(), and let apps > > > (or OSS layer) parepare (if needed) and restart the stream again. > > > > > > > > > Takashi > > > > > > > > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
