Re: [Qemu-devel] USB Tablet Emulation

[Brad Campbell <brad@wasp.net.au>]

Leonardo E. Reiter wrote:
> Sorry about that...  Brad, very well done!

Ta :)
Anthony did a great job doing the stuff I'm knaff at (making clean and mergable code) and the sdl 
hookups.
I just hacked the hid stuff (about 150 win2k reboots in there).

It works with Win98 also, but Win98 seems to want a slightly different hid config or wants 0-ffff 
rather than 0-7fff. I'm playing with that..

The wheel works in SDL although there is currently a bug where it steps by 2 instead of 1.. so it's 
ok for scrolling, but scrolling through a selection box causes it to skip every second selection.
I've not tested the wheel with the vnc patch yet. I'll get to those tonight..

> On another note, I'm looking over the USB HID spec to better understand 
> the boot-time device constraints.  I doubt you can use an absolute 
> coordinate tablet as a boot-time mouse that actually reports positions 
> in absolute terms, but maybe it's possible.  It's not a big deal, just 
> cosmetic really - to be able to use the tablet at OS install/early boot 
> time, before more complex drivers are loaded.  I'm not sure how possible 
> this is, but the USB HID spec seems to imply it.

Yes, there are tight boot time constraints.. and no from what I can find the hid required to meet 
them won't work with abs coordinates. if you absolutely *had* to do that, perhaps there might be a 
way of switching mice on the fly.. virtual unplug mouse and replug tablet, or enable ps2 for boot 
and then some way of causing a tablet plug in at the appropriate time..

I'm not sure the bochs bios handles legacy usb though, so I feel its somewhat of a moot point, as 
you *need* the OS usb drivers loaded to even pick up a legacy usb mouse device.

Brad
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