For good measure I thought I should summarise my problem again, now
that I've struggled with this a couple of days more.
It was suggested that I should use a `nrpacks=1' argument to the
snd_usb_usx2y module when using the US-122, so I have specified that
using modconf.
Now, if I boot with the US-122 connected, I can for starters see it
using lsusb:
Bus 002 Device 003: ID 1604:8007 Tascam US-122 Audio/Midi Interface
This line would contain a notice if firmware hadn't been loaded to the
device, so I can tell that part is working.
I also see it in /proc/asound/cards:
2 [USX2Y ]: USB US-X2Y - TASCAM US-X2Y
TASCAM US-X2Y (1604:8007 if 0 at 002/003)
However, I still see no /dev/dsp2, and `aplay -l' lists only my
internal card.
Now someone has told me I should use the program usx2yloader from the
alsa-firmware-loaders package to activate the US-122. However:
% sudo usx2yloader -c 2
usx2yloader: error in loading /usr/share/alsa/firmware/usx2yloader/us122.rbt
(us122.rbt is there and comes from the latest ALSA release.)
Does anyone have a suggestion on where to go from here?