These patches seem to provide the necessary bits for the keyspan
driver to go back into the kernel, with userspace firmware in nonfree:
http://lkml.org/lkml/2008/5/30/196
http://lkml.org/lkml/2008/5/30/205
I have one of these devices and would be happy to test it.
--
Eric Cooper e c c @ c m u . e d u