* Microchip Analog to Digital Converter (ADC)

The node for this driver must be a child node of a SPI controller, hence
all mandatory properties described in

        Documentation/devicetree/bindings/spi/spi-bus.txt

must be specified.

Required properties:
	- compatible:  	Must be one of the following, depending on the
			model:
				"mcp3001" (DEPRECATED)
				"mcp3002" (DEPRECATED)
				"mcp3004" (DEPRECATED)
				"mcp3008" (DEPRECATED)
				"mcp3201" (DEPRECATED)
				"mcp3202" (DEPRECATED)
				"mcp3204" (DEPRECATED)
				"mcp3208" (DEPRECATED)
				"mcp3301" (DEPRECATED)

				"microchip,mcp3001"
				"microchip,mcp3002"
				"microchip,mcp3004"
				"microchip,mcp3008"
				"microchip,mcp3201"
				"microchip,mcp3202"
				"microchip,mcp3204"
				"microchip,mcp3208"
				"microchip,mcp3301"
				"microchip,mcp3550-50"
				"microchip,mcp3550-60"
				"microchip,mcp3551"
				"microchip,mcp3553"

			NOTE: The use of the compatibles with no vendor prefix
			is deprecated and only listed because old DT use them.

	- spi-cpha, spi-cpol (boolean):
			Either SPI mode (0,0) or (1,1) must be used, so specify
			none or both of spi-cpha, spi-cpol.  The MCP3550/1/3
			is more efficient in mode (1,1) as only 3 instead of
			4 bytes need to be read from the ADC, but not all SPI
			masters support it.

	- vref-supply:	Phandle to the external reference voltage supply.

Examples:
spi_controller {
	mcp3x0x@0 {
		compatible = "microchip,mcp3002";
		reg = <0>;
		spi-max-frequency = <1000000>;
		vref-supply = <&vref_reg>;
	};
};