Re: ET1602 Touchscreen doesn't work

[Chih-Wei Huang <cwhuang@android-x86.org>]

2011/6/3 Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>:
> You should use the device capabilities, like what events it does
> generate. If it does generate X and Y axis events, that's the right
> device.

Did you mean ABS_X and ABS_Y? Actually it is.
The android framework detects the touch device by:

    // Is this an old style single-touch driver?
     if (test_bit(BTN_TOUCH, key_bitmask)
             && test_bit(ABS_X, abs_bitmask) && test_bit(ABS_Y, abs_bitmask)) {
         device->classes |= CLASS_TOUCHSCREEN;
     }

However, the output of getevent -p shows

add device 2: /dev/input/event7
  name:     "HID TOUCH HID Touch Panel"
  events:
    SYN (0000): 0000  0001  0003  0004
    KEY (0001): 0110  0111  0112
    ABS (0003): 0000  value 1428, min 0, max 4095, fuzz 0 flat 0
                0001  value 1066, min 0, max 4095, fuzz 0 flat 0
    MSC (0004): 0004

add device 3: /dev/input/event6
  name:     "HID TOUCH HID Touch Panel"
  events:
    SYN (0000): 0000  0001  0003  0004
    KEY (0001): 0140  014a  014b
    ABS (0003): 0000  value 0, min 0, max 4095, fuzz 0 flat 0
                0001  value 0, min 0, max 4095, fuzz 0 flat 0
    MSC (0004): 0004

Only event6 supports BTN_TOUCH, so it is detected
as the touch device. However, that's wrong --
event7 is the right touch device.

By removing the check test_bit(BTN_TOUCH, key_bitmask),
event7 is correctly detected and touchscreen now works.

But I still have questions:

* Is it intended to NOT support BTN_TOUCH in event7?
* Why two devices are detected by the kernel,
  while there is only one touchscreen?

-- 
Chih-Wei
Android-x86 project
http://www.android-x86.org