At Thu, 11 Mar 2004 18:43:39 +0100 (CET), Jaroslav wrote: > > On Thu, 11 Mar 2004, Takashi Iwai wrote: > > > unfortunately, the current implementation of ALSA PCM middle layer > > isn't well suited for this kind of hardwares. it'll be a bit more > > complicated than you think. > > I don't think that's this case. I'm not sure, if the basic midlevel > mechanism is understood: The midle level code expects that driver > start/stop the stream in the trigger callback, so if you can queue > more 'periods' into the DMA engine, do it and abort/pause the transfer > only the trigger callback request. You don't need to check appl/hw_ptr > in the lowlevel code.
hmm, if i understand correctly, this DMA engine needs the update of DMA queue. i.e. the driver needs to feed chunks manually in prior to the DMA start, and continues feeding the available chunks after that as long as the stream is running. this is somewhat analogous with the case with the external hardware buffer. correct me if i'm wrong. Takashi ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click _______________________________________________ Alsa-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-devel
