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+Device-tree bindings for I2C OPAL driver
+----------------------------------------
+
+Most of the device node and properties layout is specific to the firmware and
+used by the firmware itself for configuring the port. From the linux
+perspective, the properties of use are "ibm,port-name" and "ibm,opal-id".
+
+Required properties:
+
+- reg: Port-id within a given master
+- compatible: must be "ibm,opal-i2c"
+- ibm,opal-id: Refers to a specific bus and used to identify it when calling
+               the relevant OPAL functions.
+- bus-frequency: Operating frequency of the i2c bus (in HZ). Informational for
+                 linux, used by the FW though.
+
+Optional properties:
+- ibm,port-name: Firmware provides this name that uniquely identifies the i2c
+                 port.
+
+The node contains a number of other properties that are used by the FW itself
+and depend on the specific hardware implementation. The example below depicts
+a P8 on-chip bus.
+
+Example:
+
+i2c-bus@0 {
+        reg = <0x0>;
+        bus-frequency = <0x61a80>;
+        compatible = "ibm,power8-i2c-port", "ibm,opal-i2c";
+        ibm,opal-id = <0x1>;
+        ibm,port-name = "p8_00000000_e1p0";
+        #address-cells = <0x1>;
+        phandle = <0x10000006>;
+        #size-cells = <0x0>;
+        linux,phandle = <0x10000006>;
+};