From: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>

Add documentation for USB3 PHY available in NS2 SoC

Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yendapally.reddy-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
Signed-off-by: Jon Mason <jon.mason-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
---
 .../devicetree/bindings/phy/brcm,ns2-usb3-phy.txt  | 48 ++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/brcm,ns2-usb3-phy.txt

diff --git a/Documentation/devicetree/bindings/phy/brcm,ns2-usb3-phy.txt b/Documentation/devicetree/bindings/phy/brcm,ns2-usb3-phy.txt
new file mode 100644
index 000000000000..b1c058c37d54
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/brcm,ns2-usb3-phy.txt

@@ -0,0 +1,48 @@
+Broadcom USB3 dual port phy for Northstar2 SoC
+This is a child bus node of "brcm,mdio-mux-iproc" node.
+
+Required mdio bus properties:
+- reg: MDIO Bus number for the MDIO interface
+- #address-cells: must be 1
+- #size-cells: must be 0
+
+Required PHY properties:
+- compatible: should be "brcm,ns2-usb3-phy"
+- reg: MDIO Phy ID for the MDIO interface
+- #phy-cells: must be 0
+- #address-cells: must be 1
+- #size-cells: must be 0
+
+Sub-nodes:
+  Each port's PHY should be represented as a sub-node.
+
+Sub-nodes required properties:
+ - reg: the PHY number
+ - phy-cells: from the generic PHY bindings, must be 0
+
+Example:
+
+mdio@1 {
+	reg = <0x1>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	usb3_phy: usb3_phy@0 {