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).
Does all pcm devices support channel map ?
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
BTW. It seem that the patch for USB audio is still missing as some USB card support 5.1/7.1