Atmel PTC Subsystem

The Atmel Peripheral Touch Controller subsystem offers built-in hardware
for capacitive touch measurement on sensors that function as buttons, sliders
and wheels.

Required properties:
- compatible: 		Must be "atmel,sama5d2-ptc"
- reg: 			Address, length of the shared memory and ppp registers location
			and length.
- clocks: 		Phandlers to the clocks.
- clock-names: 		Must be "ptc_clk", "ptc_int_osc", "slow_clk".

Example:
	ptc@fc060000 {
		compatible = "atmel,sama5d2-ptc";
		reg = <0x00800000 0x10000
		       0xfc060000 0xcf>;
		interrupts = <58 IRQ_TYPE_LEVEL_HIGH 7>;
		clocks = <&ptc_clk>, <&main>, <&clk32k>;
		clock-names = "ptc_clk", "ptc_int_osc", "slow_clk";
	};
