At Fri, 31 Aug 2007 09:37:14 -0700, John Utz wrote: > > Hi Takashi; > > tnx so much for your suggestion, however, 'tis a bit more complicated > methinks.... > > On Fri, 31 Aug 2007 13:20:29 +0200 > "Takashi Iwai" <tiwai@xxxxxxx> wrote: > > > At Thu, 30 Aug 2007 12:42:10 -0700, > > John Utz wrote: > > > > > > > It seems like the right thing to do would be to check if any other > > > > DACs are in use. > > > > > > perhaps, but i dont think that there is a 'DAC IN USE' function. Are > > > you aware of one? > > > > Not in the ac97_codec side. > > Usually the rate-lock over streams is implemented in the controller > > side. > > Ok, but in the case of the VT1618 it's implemented on the codec itself > and i have no choice. > > With that in mind, is the fact that it's usually done on the controller > side relevant? Does this chip fact modify your thoughts? The problem is that it's the controller who handles DMA and decides which stream to play. AC97 is just a slave, which does the DA/AD conversion. So, what you have to take care is rather the controller side. > So, by controller, do you mean the via8237 (via82xx) side? > > I had pondered doing it there, but that would require the via82xx code > to know something about the codec that it's controlling and that code > at present seems to know nothing about the child codecs, how would i > get the codec ID value back to the via82xx code in order for it to do > any decision making? VIA82xx can't control the multi-channel streams in separate DMAs, AFAIK. The multi-stream mode is for the single-codec and via82xx itself mixes the streams. Thus, it's neither for multi codecs nor multi-channel.s In the multi-channel mode, it can handle only one stream with multiple channels. So, you cannot start/stop the stream for each channel/codec separately. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
