[Build] Touch Panels

[nils at shkoo.com]

On Mon, 28 Sep 2009, dpc wrote:
>> the calibration they supply for linux is limited to determining the
>> minimum and maximum x and y values.
>
> hmmm... i have to go back over the driver objdump (since i'm just
> playing along from home) to see if this makes a difference.

To elaborate, the touchscreen sends 2 position values between 0x0000 and 
0x3FFF.  The inexio-supplied (closed source) linux calibration tool 
calibrates how those map to display coordinates.  I guess it is closed 
source and I didn't reverse engineer what it did, so it might be sending 
some data back over the serial port to the touchscreen to do some 
additional calibration.

The inexio driver that I'm using now (http://repo.or.cz/w/inexio.git) just 
uses 0x0000,0x0000 as the upper left corner and 0x3FFF,0x3FFF as the 
bottom right corner.  It doesn't look like it does any calibration 
compensation at all.

-nils