Hi > On Wed, 11 May 2016 04:28:41 +0200, > Shengjiu Wang wrote: > > > > Hi > > > > > -----Original Message----- > > > From: Takashi Iwai [mailto:tiwai@xxxxxxx] > > > Sent: Tuesday, May 10, 2016 4:22 PM > > > To: Shengjiu Wang > > > Cc: perex@xxxxxxxx; alsa-devel@xxxxxxxxxxxxxxxx > > > Subject: Re: [PATCH] pcm: Don't store the state for > > > SND_PCM_STATE_SUSPENDED > > > > > > On Tue, 10 May 2016 09:45:46 +0200, > > > Shengjiu Wang wrote: > > > > > > > > The resume function don't update the dmix->state, if store > SUSPENDED > > > > state in snd_pcm_dmix_state, the write function after resume will > > > > return error -ESTRPIPE, because the snd_pcm_write_areas() will > check > > > > the state of the pcm device. > > > > This patch remove the store SND_PCM_STATE_SUSPENDED state > operation > > > > for dmix,dshare,dsnoop. > > > > > > > > Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxxxxxxxx> > > > > > > What's the exact problem you're seeing on surface? Could > illustrate > > > how the bug is triggered and how to reproduce easily? It'll make > > > easier to understand what you're trying to fix. > > > > > > > > > thanks, > > > > > > Takashi > > > > The aplay endlessly print " Suspended. Trying resume. Done." if > suspend > > and resume in the middle of playback. Which is caused by this patch. > > > > commit 8985742d91dbdd74b2f605374207473393454fff > > Author: Takashi Iwai <tiwai@xxxxxxx> > > Date: Fri Oct 30 17:13:50 2015 +0100 > > > > pcm: dmix: Handle slave PCM xrun and unexpected states properly > > > > This patch store the SUSPENDED state to dmix->state, but after resume > > the dmix->state still is SUSPENDED, next write function will check > the > > state, if state is SUSPENDED, it will return -ESTRPIPE, then the > aplay > > will print another " Suspended. Trying resume. Done." Then repeat > this > > behavior again and again. > > Thanks, this is exactly what I wanted to see in the changelog! > It's rather a regression, and it should be clearly mentioned. > > Now about your fix: the problem is not about setting the correct > state at suspending. It is suspended, so setting the right state > there is the correct behavior. However, the counterpart, the resume, > is the culprit of this bug. It misses the restore of the shadow > state. > > Does the patch below work instead? > Yes, it is workable. Best regards Wang Shengjiu > > Takashi > > --- > diff --git a/src/pcm/pcm_direct.c b/src/pcm/pcm_direct.c > index 14de734d98eb..e28738b0de96 100644 > --- a/src/pcm/pcm_direct.c > +++ b/src/pcm/pcm_direct.c > @@ -848,6 +848,7 @@ int snd_pcm_direct_resume(snd_pcm_t *pcm) > snd_pcm_start(dmix->spcm); > err = 0; > } > + dmix->state = snd_pcm_state(dmix->spcm); > snd_pcm_direct_semaphore_up(dmix, DIRECT_IPC_SEM_CLIENT); > return err; > } _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
