* Freescale MPR121 Controllor

Required Properties:
- compatible:		Should be "fsl,mpr121-touchkey"
- reg:			The I2C slave address of the device.
- interrupts:		The interrupt number to the cpu.
- vdd-supply:		Phandle to the Vdd power supply.
- linux,keycodes:	Specifies an array of numeric keycode values to
			be used for reporting button presses. The array can
			contain up to 12 entries.

Optional Properties:
- wakeup-source:	Use any event on keypad as wakeup event.
- autorepeat:		Enable autorepeat feature.

Example:

#include "dt-bindings/input/input.h"

	touchkey: mpr121@5a {
		compatible = "fsl,mpr121-touchkey";
		reg = <0x5a>;
		interrupt-parent = <&gpio1>;
		interrupts = <28 2>;
		autorepeat;
		vdd-supply = <&ldo4_reg>;
		linux,keycodes = <KEY_0>, <KEY_1>, <KEY_2>, <KEY_3>,
				<KEY_4> <KEY_5>, <KEY_6>, <KEY_7>,
				<KEY_8>, <KEY_9>, <KEY_A>, <KEY_B>;
	};