Documentation: DT: omap-ssi binding documentation

OMAP SSI controller bindings

OMAP Synchronous Serial Interface (SSI) controller implements a legacy

variant of MIPI's High Speed Synchronous Serial Interface (HSI).

Required properties:

- compatible:		Should include "ti,omap3-ssi".

- reg-names:		Contains the values "sys" and "gdd" (in this order).

- reg:			Contains a matching register specifier for each entry

			in reg-names.

- interrupt-names:	Contains the value "gdd_mpu".

- interrupts: 		Contains matching interrupt information for each entry

			in interrupt-names.

- ranges:		Represents the bus address mapping between the main

			controller node and the child nodes below.

- clock-names:		Must include the following entries:

  "ssi_ssr_fck": The OMAP clock of that name

  "ssi_sst_fck": The OMAP clock of that name

  "ssi_ick": The OMAP clock of that name

- clocks:		Contains a matching clock specifier for each entry in

			clock-names.

- #address-cells:	Should be set to <1>

- #size-cells:		Should be set to <1>

Each port is represented as a sub-node of the ti,omap3-ssi device.

Required Port sub-node properties:

- compatible:		Should be set to the following value

			ti,omap3-ssi-port (applicable to OMAP34xx devices)

- reg-names:		Contains the values "tx" and "rx" (in this order).

- reg:			Contains a matching register specifier for each entry

			in reg-names.

- interrupt-parent	Should be a phandle for the interrupt controller

- interrupts:		Should contain interrupt specifiers for mpu interrupts

			0 and 1 (in this order).

- ti,ssi-cawake-gpio:	Defines which GPIO pin is used to signify CAWAKE

			events for the port. This is an optional board-specific

			property. If it's missing the port will not be

			enabled.

Example for Nokia N900:

ssi-controller@48058000 {

	compatible = "ti,omap3-ssi";

	/* needed until hwmod is updated to use the compatible string */

	ti,hwmods = "ssi";

	reg = <0x48058000 0x1000>,

	      <0x48059000 0x1000>;

	reg-names = "sys",

		    "gdd";

	interrupts = <55>;

	interrupt-names = "gdd_mpu";

	clocks = <&ssi_ssr_fck>,

		 <&ssi_sst_fck>,

		 <&ssi_ick>;

	clock-names = "ssi_ssr_fck",

		      "ssi_sst_fck",

		      "ssi_ick";

	#address-cells = <1>;

	#size-cells = <1>;

	ranges;

	ssi-port@4805a000 {

		compatible = "ti,omap3-ssi-port";

		reg = <0x4805a000 0x800>,

		      <0x4805a800 0x800>;

		reg-names = "tx",

			    "rx";

		interrupt-parent = <&intc>;

		interrupts = <67>,

			     <68>;

		ti,ssi-cawake-gpio = <&gpio5 23 GPIO_ACTIVE_HIGH>; /* 151 */

	}

	ssi-port@4805a000 {

		compatible = "ti,omap3-ssi-port";

		reg = <0x4805b000 0x800>,

		      <0x4805b800 0x800>;

		reg-names = "tx",

			    "rx";

		interrupt-parent = <&intc>;

		interrupts = <69>,

			     <70>;

		status = "disabled"; /* second port is not used on N900 */

	}

}