Re: kern/46391: ums.c doesn't support digitizers or touchscreens

[Pierre Pronchery <khorben%defora.org@localhost>]

                        Hi Nat,

On Mon, 30 Apr 2012 14:05:00 +0000, nathanialsloss wrote:
> 
> I have a laptop with a touchscreen that was supported by ums.c as a usb 
mouse.  After upgrading my bios it now reports as a digitizer and was no 
longer supported by ums.c.  And instead of reporting buttons it now 
reports as tip, barrel and eraser switches.
> 
> Note: The digitizer type is 0002 which was undefined but I think it 
means digitizer.  This patch is my own work and I submit it under the 
NetBSD license.

According to http://www.freebsddiary.org/APC/usb_hid_usages.php, type 
0002 is "Pen". This is also not expected by the uts(4) driver, but I 
wonder if it wouldn't have made more sense to patch it instead of ums(4).

> I think it would also be possible to mach against digitizer touchscreens 
type 0004.  But I didn't add it as I don't have the hardware to test.

One more thing that I was very useful while I was debugging uts(4): it is 
very likely that your touchscreen supports different "input modes", and 
that your BIOS simply changed the default one. You can use usbhidctl to 
list and modify these properties.

PS: I have a few questions:
- how do you handle calibration, and absolute coordinates?
- does it simply work directly out of the box?
- is your screen resolution always set to the maximum available?

Cheers,
-- 
khorben