The driver backend is capable of supporting also ISA cards (no DMA)
and primary rate (PRI) cards in addition to the basic rate ones,
but I don't any to test on right now, so we don't support those
currently.
This code was originally written by Juha-Matti Liukkonen <jml@cubical.fi>
of Cubical Solutions Ltd. for FreeBSD, and was ported to NetBSD by
myself for the same company.
