At Wed, 28 Mar 2007 15:15:28 +0200, Rene Herman wrote: > > On 03/28/2007 01:40 PM, Takashi Iwai wrote: > > > At Wed, 28 Mar 2007 13:03:51 +0200, > > Rene Herman wrote: > > >>> Bingo, that's it. "arecord --period-size=4096 --buffer-size=16384 -f cd" > >>> works fine. I guess it should be forcing power of 2 then? > >> Only --period-size=4096 is not enough. It then has a buffer-size of > >> 22016 and the stutter is there. > >> > >> --buffer-size=8192 --period-size=4000 is fine though. So, buffer-size... > > > > You can try snd_pcm_hw_constraint_pow2() there. > > Seems to work nicely! With the attached, a simple "arecord -f cd" works > without problem (it then sets buffer_size 16384, period_size 4096) and > seems to be settling on the nearest power of two if I pass something in > for buffer_size manually. > > > But, IIRC, power-of-two constraint causes problems when you use > > buffer_time instead of buffer_size. Anyway, worth try once. > > I don't seem to be experiencing problems there either; > > command | buffer_size/period_size > ------------------------------------------------------------ > arecord -f cd --buffer-time 100000 | 4096/1103 > arecord -f cd --buffer-time 150000 | 8192/1654 > arecord -f cd --buffer-time 200000 | 16384/2205 > > These all work fine. With --period-time: > > command | buffer_size/period_size > ----------------------------------------------------------- > arecord -f cd --period-time 20000 | 16384/882 > arecord -f cd --period-time 35000 | 16384/1544 > arecord -f cd --period-time 50000 | 16384/2205 > > All fine again. If I try upsetting the thing on purpose with large > values, I get errors (from arecord, not in the sound). > > As far as I'm concerned this seems good to go. Signed-off-by/Tested-by > and all that. OK, then it's good. I applied the fix together with cleanup of superfluous '#if 0's. thanks, Takashi > > Rene. > > [2 es1968_buffer_pow2.diff <text/plain (7bit)>] > diff --git a/sound/pci/es1968.c b/sound/pci/es1968.c > index dc84c18..8130a87 100644 > --- a/sound/pci/es1968.c > +++ b/sound/pci/es1968.c > @@ -1617,6 +1617,8 @@ #if 0 > snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, > 1024); > #endif > + snd_pcm_hw_constraint_pow2(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES); > + > spin_lock_irq(&chip->substream_lock); > list_add(&es->list, &chip->substream_list); > spin_unlock_irq(&chip->substream_lock); _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
