userland driver?

[Robert Watson]

On Wed, 11 Feb 2009, Andriy Gapon wrote:

> has anybody tried anything in the area of userland drivers on FreeBSD? I 
> mean a driver for something sufficiently simple and standalone and not 
> driven by interrupts. E.g. some sort of a watchdog driver that simply 
> reads/writes some io registers from time to time.
>
> Brute-force and a very bad way is to go through /dev/mem, /dev/io, /dev/pci, 
> but I am thinking about something that would allow to plug into newbus 
> framework from userland.

I recently had a related question from a colleague about implementing a 
synthetic USB device in userspace so that software part development can occur 
concurrently with hardware part development.

Robert N M Watson
Computer Laboratory
University of Cambridge