linux-arkmicro/linux/Documentation/devicetree/bindings/input/touchscreen/bu21029.txt

* Rohm BU21029 Touch Screen Controller

Required properties:
 - compatible              : must be "rohm,bu21029"
 - reg                     : i2c device address of the chip (0x40 or 0x41)
 - interrupt-parent        : the phandle for the gpio controller
 - interrupts              : (gpio) interrupt to which the chip is connected
 - rohm,x-plate-ohms       : x-plate resistance in Ohm

Optional properties:
 - reset-gpios             : gpio pin to reset the chip (active low)
 - touchscreen-size-x      : horizontal resolution of touchscreen (in pixels)
 - touchscreen-size-y      : vertical resolution of touchscreen (in pixels)
 - touchscreen-max-pressure: maximum pressure value
 - vdd-supply              : power supply for the controller

Example:

	&i2c1 {
		/* ... */

		bu21029: bu21029@40 {
			compatible = "rohm,bu21029";
			reg = <0x40>;
			interrupt-parent = <&gpio1>;
			interrupts = <4 IRQ_TYPE_EDGE_FALLING>;
			reset-gpios = <&gpio6 16 GPIO_ACTIVE_LOW>;
			rohm,x-plate-ohms = <600>;
			touchscreen-size-x = <800>;
			touchscreen-size-y = <480>;
			touchscreen-max-pressure = <4095>;
		};

		/* ... */
	};