USB data or audio capture on 64-bit PPC Linux?

[If you are trimming followups, please put your reply into
comp.arch.embedded as I don't regularly read the other two NGs where
I've posted this].

I'm looking for recommendations on a USB data capture pod or (ideally)
a cheap audio input device that is known to have working driver
support for 64-bit PowerPC Linux. At minimum I need to capture one 10-
bit ADC channel at 22.1kHz; anything friskier would be great, and my
ideal would be 48kHz 16-bit stereo.

I need to get this working on the PlayStation 3, and I really can't
find anything that's documented specifically enough to PPC Linux that
I can feel confident about buying it.

This is a one-off project; I'd even be happy to buy a used one from
some Usenet denizen, as long as it was guaranteed I'd be able to get
it working.