Hey Takashi, Glad that this issue with bidirectional PCM hints was patched. :) I appreciate your help and input! Thanks, - Trent Reed On Thu, May 12, 2016 at 7:38 AM, Takashi Iwai <tiwai@xxxxxxx> wrote: > On Sat, 07 May 2016 05:19:45 +0200, > Trent Reed wrote: >> >> Hey All, >> >> (Tried to send an email earlier, it didn't seem to send?) >> >> I'm trying to understand ALSA, having a little trouble with some >> errors that I can't ration over. >> Gist Repro: https://gist.github.com/TReed0803/353ce27d37bc1ebe965854ea88c8b97b >> >> Whenever I run the above simple code (iterate over PCM stream hints, >> open for Playback/Capture depending on IOID; output also provided at >> link above) I notice that I sometimes hit errors. I'm having trouble >> understanding these errors, because as I understand I'm using the ALSA >> library correctly. For example, dmix is telling me that it "Only >> supports playback streams", well then, why does the hint IOID return >> that it supports capture as well? (same for dsnoop). > > Oh, these are real bugs. They shouldn't have been listed as > bidirectional, indeed. The fix patches are below. > >> More confusing >> are the "ALSA lib pcm_route.c:867:(find_matching_chmap) Found no >> matching channel map" errors. > > This is a bit more complicated. I suppose you're testing with > HD-audio, right? HD-audio has a restriction that it accepts only even > numbered streams (2, 4, 6, 8). The error comes from the definition of > surround21, i.e. the odd numbers. But, you can still use this > definition by wrapping with plug, so that the missing one channel is > filled automatically while using the given channel allocation. > > thanks, > > Takashi > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
