Altera Mailbox Driver
=====================

Required properties:
- compatible :	"altr,mailbox-1.0".
- reg : 	physical base address of the mailbox and length of
		memory mapped region.
- #mbox-cells:	Common mailbox binding property to identify the number
		of cells required for the mailbox specifier. Should be 1.

Optional properties:
- interrupt-parent :	interrupt source phandle.
- interrupts :		interrupt number. The interrupt specifier format
			depends on the interrupt controller parent.

Example:
	mbox_tx: mailbox@100 {
		compatible = "altr,mailbox-1.0";
		reg = <0x100 0x8>;
		interrupt-parent = < &gic_0 >;
		interrupts = <5>;
		#mbox-cells = <1>;
	};

	mbox_rx: mailbox@200 {
		compatible = "altr,mailbox-1.0";
		reg = <0x200 0x8>;
		interrupt-parent = < &gic_0 >;
		interrupts = <6>;
		#mbox-cells = <1>;
	};

Mailbox client
===============
"mboxes" and the optional "mbox-names" (please see
Documentation/devicetree/bindings/mailbox/mailbox.txt for details). Each value
of the mboxes property should contain a phandle to the mailbox controller
device node and second argument is the channel index. It must be 0 (hardware
support only one channel).The equivalent "mbox-names" property value can be
used to give a name to the communication channel to be used by the client user.

Example:
	mclient0: mclient0@400 {
		compatible = "client-1.0";
		reg = <0x400 0x10>;
		mbox-names = "mbox-tx", "mbox-rx";
		mboxes = <&mbox_tx 0>,
			 <&mbox_rx 0>;
	};
