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Chrome OS CROS_EC Binding
======================

The device tree node which describes the operation of the CROS_EC interface
is as follows:

Required properties :
- compatible = "google,cros-ec"

Optional properties :
- spi-max-frequency : Sets the maximum frequency (in Hz) for SPI bus
   operation
- i2c-max-frequency : Sets the maximum frequency (in Hz) for I2C bus
   operation
- ec-interrupt : Selects the EC interrupt, defined as a GPIO according
   to the platform
- optimise-flash-write : Boolean property - if present then flash blocks
   containing all 0xff will not be written, since we assume that the EC
   uses that pattern for erased blocks

The CROS_EC node should appear as a subnode of the interrupt that connects it
to the EC (e.g. i2c, spi, lpc). The reg property (as usual) will indicate
the unit address on that bus.


Example
=======

	spi@131b0000 {
		cros-ec@0 {
			reg = <0>;
			compatible = "google,cros-ec";
			spi-max-frequency = <5000000>;
			ec-interrupt = <&gpio 174 1>;
			optimise-flash-write;
			status = "disabled";
		};
	};