At Mon, 17 Sep 2012 18:46:32 +0800, Raymond Yau wrote: > > > > How about those sound card which use multi plugin for multi channels > (e.g. > > > emu10k1 , c0106 and cs4630) as they can also provide a rear or clfe > device > > > for independent stereo playback ? > > > > The case of emu10k1 is a bit difficult, as the routing is completely > > dynamic and determined in alsa-lib plugin. So, my plan for this case > > is to provide the chmap override in the alsa-lib config definition for > > emu10k1 surrounds. > > > But the routing of device 0 "hw" is not as same as front device since the > driver pan the output to both front and rear jacks (upmixing). The hw device doesn't provide any map. It's only for "front", "rear" whatever in strict channel position definitions. > Does all pcm devices support channel map ? No. The channel map is an optional feature. > How about those 16 channels multichannel playback and capture devices ? > > card 0: Live [SB Live! Platinum [CT4760P]], device 2: emu10k1 efx > [Multichannel Capture/PT Playback] > Subdevices: 8/8 > > card 0: Live [SB Live! Platinum [CT4760P]], device 3: emu10k1 [Multichannel > Playback] > Subdevices: 1/1 > > **** List of CAPTURE Hardware Devices **** > > card 0: Live [SB Live! Platinum [CT4760P]], device 2: emu10k1 efx > [Multichannel Capture/PT Playback] > Subdevices: 1/1 Such devices are not supported. If any, they can be mapped using DRIVER_SPEC flag. > BTW. It seem that the patch for USB audio is still missing as some USB card > support 5.1/7.1 Feel free to submit a patch :) Takashi
