OFW - calibrate Raydium touchscreen

[wmb@…]

The EETI touchscreen needs calibration after assembly, otherwise there may be dead zones or other mis-tracking.

It would be good to do it during factory test.

That said, I wonder if the calibration might drift before the unit is deployed, maybe as a result of temperature, altitude, humidity, shipping conditions, or other factors. So it might be a good idea to recalibrate it somewhere else too, perhaps just before booting, or somewhere in the Linux startup.

[wmb@…]

Implemented by svn 2896. Test build at http://dev.laptop.org/~wmb/q4d04me.rom

You can test it as follows:

Decalibrate the touchscreen.  Type the following line and hold your palm on
the screen as you type the "enter".  Hold you palm on the screen for 2 seconds
afterwards.

  ok select /touchscreen  calibrate  unselect

Disable autocalibration and verify that the calibration is bad:

  ok dev /touchscreen
  ok patch noop calibrate selftest
  ok dend
  ok test /touchscreen

The tracking should be bad, reflecting the miscalibration.

Verify that the autocalibration fixes it:

  ok dev /touchscreen
  ok patch calibrate noop selftest
  ok dend
  ok test /touchscreen

[Quozl]

Is in Q4D06.