* Texas Instruments' ADC0831/ADC0832/ADC0832/ADC0838

Required properties:
 - compatible: Should be one of
	* "ti,adc0831"
	* "ti,adc0832"
	* "ti,adc0834"
	* "ti,adc0838"
 - reg: spi chip select number for the device
 - vref-supply: The regulator supply for ADC reference voltage
 - spi-max-frequency: Max SPI frequency to use (< 400000)

Example:
adc@0 {
	compatible = "ti,adc0832";
	reg = <0>;
	vref-supply = <&vdd_supply>;
	spi-max-frequency = <200000>;
};