I honestly don’t know the exact state of USB compatibility, anyway it could be an interesting feature to have (and may attract more users… of course speaking of R1).
This is an open source (Apache) version for Windows:
Hope that inspires.
Not sure if it will work for sure, but the linux ADB driver uses libusb, which haiku has a port of. Assuming the libusb in haiku is fully working, this ought to be a trivial port, I think?