Excerpts from netbsd: 10-Feb-98 Detaching devices Lennart
Augustsson@cs.ch (719*)

> Our current config system works great for attaching devices, (through
> the probe and attach routines) but there is no support for detaching
> them, as far as I can tell.  Is there any work going on in this
> direction?

I've implemented a config_detach() function as part
of a loadable driver framework some years ago.
(Parts of it went into John Kohl's PCMCIA framework
later.)
To load/unload driver LKMs, it needs some serious
changes in the autoconf framework which people
didn't like.
However, it's useful for driver development. I can give
you a copy if you want.

best regards
Matthias