* Texas Instruments' ADS8684 and ADS8688 ADC chip

Required properties:
 - compatible: Should be "ti,ads8684" or "ti,ads8688"
 - reg: spi chip select number for the device

Recommended properties:
 - spi-max-frequency: Definition as per
		Documentation/devicetree/bindings/spi/spi-bus.txt

Optional properties:
 - vref-supply: The regulator supply for ADC reference voltage

Example:
adc@0 {
	compatible = "ti,ads8688";
	reg = <0>;
	vref-supply = <&vdd_supply>;
	spi-max-frequency = <1000000>;
};
