DESK-MP1-L/Peripherals/Touchscreen

History
Version	Issue Date	Notes
X.Y.Z	01/08/2023	DESK-MP1-L-1.0.0 release

Touchscreen

The screen supplied with the kit has a capacitive touchscreen, it is connected to the board via the USB OTG port

Are present also an i2c port (J20) for use other touchscreen eg. Ilitek i2c touchscreen, the driver ILI210X are already present on kernel, compatible with ili210x, ili2117, ili2120, ili251x

For add ilitek i2c touscreen add ilitek@41 node on kernel devicetree:

...
...
soc {
    ...
    ...
    i2cmux{
    ...
    ...
        i2c@0{
            ...
            ...
                ilitek@41 {
                    compatible = "ilitek,ili251x";
                    reg = <0x41>;
                    interrupt-parent = <&gpiod>;
                    interrupts = <15 IRQ_TYPE_EDGE_FALLING>;
                    vin-supply = <&touch_vdd>;
                    ilitek,irq-gpio = <&gpiod 15 GPIO_ACTIVE_LOW>;
                    ilitek,reset-gpio = <&gpiod 14 GPIO_ACTIVE_LOW>;
                    ilitek,name = "ilitek_i2c";
                    touchscreen-size-x = <16384>;
                    touchscreen-size-y = <9600>;
                };
            ...
            ...
        };
        ...
        ...
    };
    ...
    ...
};
...
...

Calibration

Calibration is not necessary as it is a capacitive and non-resistive touch screen which does require calibration.

In any case if you use the tslib API you need to calibrate with ts_calibrate and then with ts_test check that the touscreen works correctly.