ARM: tegra: add DT nodes for Tegra USB PHY

Add DT nodes for Tegra USB PHY along with related documentation.
Also added a phandle property to controller DT node, for referring
to connected PHY instance.
Signed-off-by: NVenu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt

@@ -11,6 +11,7 @@ Required properties :
  - phy_type : Should be one of "ulpi" or "utmi".
  - nvidia,vbus-gpio : If present, specifies a gpio that needs to be
    activated for the bus to be powered.
+ - nvidia,phy : phandle of the PHY instance, the controller is connected to.
 
 Required properties for phy_type == ulpi:
   - nvidia,phy-reset-gpio : The GPIO used to reset the PHY.

Documentation/devicetree/bindings/usb/nvidia,tegra20-usb-phy.txt

+Tegra SOC USB PHY
+
+The device node for Tegra SOC USB PHY:
+
+Required properties :
+ - compatible : Should be "nvidia,tegra20-usb-phy".
+ - reg : Address and length of the register set for the USB PHY interface.
+ - phy_type : Should be one of "ulpi" or "utmi".
+
+Optional properties:
+  - nvidia,has-legacy-mode : boolean indicates whether this controller can
+    operate in legacy mode (as APX 2500 / 2600). In legacy mode some
+    registers are accessed through the APB_MISC base address instead of
+    the USB controller.
\ No newline at end of file

arch/arm/boot/dts/tegra20.dtsi

@@ -400,6 +400,25 @@
 		#size-cells = <0>;
 	};
 
+	phy1: usb-phy@c5000400 {
+		compatible = "nvidia,tegra20-usb-phy";
+		reg = <0xc5000400 0x3c00>;
+		phy_type = "utmi";
+		nvidia,has-legacy-mode;
+	};
+
+	phy2: usb-phy@c5004400 {
+		compatible = "nvidia,tegra20-usb-phy";
+		reg = <0xc5004400 0x3c00>;
+		phy_type = "ulpi";
+	};
+
+	phy3: usb-phy@c5008400 {
+		compatible = "nvidia,tegra20-usb-phy";
+		reg = <0xc5008400 0x3C00>;
+		phy_type = "utmi";
+	};
+
 	usb@c5000000 {
 		compatible = "nvidia,tegra20-ehci", "usb-ehci";
 		reg = <0xc5000000 0x4000>;
@@ -408,6 +427,7 @@
 		nvidia,has-legacy-mode;
 		clocks = <&tegra_car 22>;
 		nvidia,needs-double-reset;
+		nvidia,phy = <&phy1>;
 		status = "disabled";
 	};
 
@@ -417,6 +437,7 @@
 		interrupts = <0 21 0x04>;
 		phy_type = "ulpi";
 		clocks = <&tegra_car 58>;
+		nvidia,phy = <&phy2>;
 		status = "disabled";
 	};
 
@@ -426,6 +447,7 @@
 		interrupts = <0 97 0x04>;
 		phy_type = "utmi";
 		clocks = <&tegra_car 59>;
+		nvidia,phy = <&phy3>;
 		status = "disabled";
 	};