Doing another "run through"  FreeBSD -> NetBSD acx() driver conversion, I 
was using the the wi() wireless driver as a template, but it will need 
bus_dma commands as well -- these are in the ath() wireless driver (also 
documentation in http://che.ojctech.com/~dyoung/public/bus_dma.pdf).

http://sthigpen.freshell.org/code/wireless-framework

Sam.