[Xorg] XInput Hotplug Additions

[Joe Krahn]

Keith Packard wrote:
> 
> Yeah, I don't see any reason to continue to support user-level device 
> drivers when few (any?) systems need them any more.  If you want hot-plug, 
> then you get to create a reasonable input system.  For really broken 
> environments, a user-level process could open the device and submit 
> standard format events through some back-channel.
My concept is that the back-channel is just the X-server XInput
protocol. That way, one server can be set up to proxy access to a
device on another server, or to a "micro server" that uses the
X-server protocol - assuming that a really bare bones server
with no screens is not too difficult or verbose for just sending
device events.

Also, I think user drivers are still useful if you have a
device not supported by non-Windows OSes. Of course, the newer USB
HID based devices should mean mot things are automatically supported.

Joe Krahn