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+NVIDIA Tegra XUSB mailbox
+=========================
+
+The Tegra XUSB mailbox is used by the Tegra xHCI controller's firmware to
+communicate requests to the host and PHY drivers.
+
+Refer to ./mailbox.txt for generic information about mailbox device-tree
+bindings.
+
+Required properties:
+--------------------
+ - compatible: Should be "nvidia,tegra124-xusb-mbox".
+ - reg: Address and length of the XUSB FPCI registers.
+ - interrupts: XUSB mailbox interrupt.
+ - #mbox-cells: Should be 0. There is only one physical channel.
+
+Example:
+--------
+ xusb_mbox: mailbox@0,70098000 {
+ compatible = "nvidia,tegra124-xusb-mbox";
+ reg = <0x0 0x70098000 0x0 0x1000>;
+ interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>;
+
+ #mbox-cells = <0>;
+ };
+
+ usb@0,70090000 {
+ ...
+ mboxes = <&xusb_mbox>;
+ mbox-names = "xusb";
+ ...
+ };