importing firmware and code from openbsd:

http://firmware.openbsd.org/firmware-dist/rsu-1.2.tgz
http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/dev/usb/if_rsu.c?rev=1.17;content-type=text%2Fplain
http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/dev/usb/if_rsureg.h?rev=1.3;content-type=text%2Fplain