* Freescale (Enhanced) Configurable Serial Peripheral Interface
  (CSPI/eCSPI) for i.MX

Required properties:
- compatible : Should be "fsl,<soc>-cspi" or "fsl,<soc>-ecspi"
- reg : Offset and length of the register set for the device
- interrupts : Should contain CSPI/eCSPI interrupt
- fsl,spi-num-chipselects : Contains the number of the chipselect
- cs-gpios : Specifies the gpio pins to be used for chipselects.
- dmas: DMA specifiers for tx and rx dma. See the DMA client binding,
		Documentation/devicetree/bindings/dma/dma.txt
- dma-names: DMA request names should include "tx" and "rx" if present.

Example:

ecspi@70010000 {
	#address-cells = <1>;
	#size-cells = <0>;
	compatible = "fsl,imx51-ecspi";
	reg = <0x70010000 0x4000>;
	interrupts = <36>;
	fsl,spi-num-chipselects = <2>;
	cs-gpios = <&gpio3 24 0>, /* GPIO3_24 */
		   <&gpio3 25 0>; /* GPIO3_25 */
	dmas = <&sdma 3 7 1>, <&sdma 4 7 2>;
	dma-names = "rx", "tx";
};