On Wed, Apr 29, 2009 at 10:35 AM, Jon Smirl <jonsmirl@xxxxxxxxx> wrote: > On Wed, Apr 29, 2009 at 9:04 AM, Takashi Iwai <tiwai@xxxxxxx> wrote: >> At Wed, 29 Apr 2009 08:58:52 -0400, >> Jon Smirl wrote: >>> >>> My hardware was has three stereo i2s lines. These three lines are all >>> tied to the same external clock so they are synchronized. Because >>> there are three i2s lines, each with it's own DMA queue and FIFO, I >>> need three independent output buffers. What is the correct way to set >>> this up in ALSA? >> >> So I suppose it's three streams of 2-ch interleaved format? > > Yes > >> If so, an easier way would be to provide three substreams in a PCM, >> and bind 6 channels with alsa-lib plugin. > > How does ALSA start the streams synchronously? I can start the streams synchronously at the low level by waiting for the frame clock and then enabling the three DMA channels. > >> >> Another possible way would be to set up channel_info to point a proper >> offset for each channel. But, this is less common and maybe more >> problematic. >> >> >> Takashi >> > > > > -- > Jon Smirl > jonsmirl@xxxxxxxxx > -- Jon Smirl jonsmirl@xxxxxxxxx _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
