@uzanto Unlikely, the square is about 80x50mm. Not even sure where libinput got these values from. I listed the usb device using
usb -v but the report descriptors are blocked while the driver (usbhid) sits on it…
echo -n 3-1.2:1.0 >/sys/bus/usb/drivers/usbhid/unbind
echo -n 3-1.2:1.1 >/sys/bus/usb/drivers/usbhid/unbind
lsusb -v -d 27c0:0819 reports:
Item(Global): Unit, data= [ 0x11 ] 17
System: SI Linear, Unit: Centimeter
Item(Local ): Usage, data= [ 0x30 ] 48
Item(Global): Physical Minimum, data= [ 0x00 ] 0
Item(Global): Physical Maximum, data= [ 0x79 0x08 ] 2169
Item(Main ): Input, data= [ 0x02 ] 2
Data Variable Absolute No_Wrap Linear
Preferred_State No_Null_Position Non_Volatile Bitfield
Item(Global): Logical Maximum, data= [ 0x7f 0x25 ] 9599
Item(Global): Physical Maximum, data= [ 0x8a 0x03 ] 906
Item(Local ): Usage, data= [ 0x31 ] 49
So the geometry info appears to come from the USB descriptor, which is simply wrong at that point. As long as the physical size is not used, it does not matter, though.
What does matter, and so i understand @guido.gunther’s idea, is how the touch screen device is seen by the L5. From the USB-descriptors it is just a digitizer on USB, which delivers absolute positions but yet unrelated to any display.
Now where is the origin? Because the USB descriptors do not describe this, L5 has to guess, and it guesses it must the origin of its own screen causing the effect first described here as:
But contrary to the first impression, the touches are not erratically, but proportionally mapped to the L5 screen. E.g. left-upper and right-lower corner of the NexDock’s touch screen map to the respective corner of L5’s screen. Because the touches do not affect the cursor, this effect is not immediately visible, but one can validate this with a bit care and i did. The touches affect the controls and the windows boarders.
For me, this establishes, that @guido.gunther’s suspicion is right. Thus all, L5 has to know, is that the digitizer’s (touch screen) positions are to be interpreted as related to the NexDock’s screen. And that is the semantic of the setting Guido describes in his MR.
This leave to actually try it…