[LAU] RME Multiface II via direct Alsa (no Jack)

[Brent Busby]

This seems to be sort of a FAQ, because I've seen many places this is 
discussed online, but no thread or blog post ever seems to quite reach 
an answer, so I figured I'd ask...

Up until now, I've been terribly spoiled by Jack-aware applications like 
Ardour that seem to be able to automatically find all the channels on my 
Multiface and auto-name them as "playback" and "capture" channels 1 
through 18.  All this happens without me doing anything, so long as I've 
got a properly configured realtime Jack daemon running, and the 
Hammerfall mixer program is running, everything just works, which is 
fine for programs like Ardour that understand how to talk to Jack 
properly.

However, there are a lot of programs that only understand Alsa, and a 
surprising number of programs that do compile against Jack but still 
have Jack support that's very crude and doesn't actually work very well. 
(There are even a few that can only be used on Alsa at all thanks to 
Alsa's OSS emulation's fake /dev/dsp.)  Currently, I'm dealing with the 
former -- some programs that have Jack, but it's nearly useless because 
the Jack support is so bad.  I don't even need hard realtime from them. 
I just want them to see the channels on the multiface and output audio.

>From what I've gathered online, I think what I need may be a .asoundrc 
file.  Then again, maybe not:  The asoundrc documentation says that what 
it's doing is basically mapping device/channel names found in 
/proc/asound/devices (sort of the same info you get from 'aplay -L') to 
custom names and routings.  Problem is, the 18 channels of the Multiface 
all show up as *one* PCM device here!  Where are all my subdevices?  For 
that matter, if I did even try to use that one PCM, which channel would 
it come out of?  (Haven't tried it...not really that curious.)

Other people have asked this before, but most such threads seem to 
always come to "just use Jack."  Is it impossible to directly access 
these devices from Alsa?  I'm not wanting anything fancy here.  If I do 
have to write a .asoundrc, where do I get the information that HDSPMixer 
seems to innately know about how my channels map to the hardware so I 
can create one?

-- 
+ Brent A. Busby	 + "We've all heard that a million monkeys
+ UNIX Systems Admin	 +  banging on a million typewriters will
+ University of Chicago	 +  eventually reproduce the entire works of
+ Physical Sciences Div. +  Shakespeare.  Now, thanks to the Internet,
+ James Franck Institute +  we know this is not true." -Robert Wilensky