--- /dev/null
+Device tree binding for NVIDIA Tegra XUSB pad controller
+========================================================
+
+The Tegra XUSB pad controller manages a set of I/O lanes (with differential
+signals) which connect directly to pins/pads on the SoC package. Each lane
+is controlled by a HW block referred to as a "pad" in the Tegra hardware
+documentation. Each such "pad" may control either one or multiple lanes,
+and thus contains any logic common to all its lanes. Each lane can be
+separately configured and powered up.
+
+Some of the lanes are high-speed lanes, which can be used for PCIe, SATA or
+super-speed USB. Other lanes are for various types of low-speed, full-speed
+or high-speed USB (such as UTMI, ULPI and HSIC). The XUSB pad controller
+contains a software-configurable mux that sits between the I/O controller
+ports (e.g. PCIe) and the lanes.
+
+In addition to per-lane configuration, USB 3.0 ports may require additional
+settings on a per-board basis.
+
+Pads will be represented as children of the top-level XUSB pad controller
+device tree node. Each lane exposed by the pad will be represented by its
+own subnode and can be referenced by users of the lane using the standard
+PHY bindings, as described by the phy-bindings.txt file in this directory.
+
+The Tegra hardware documentation refers to the connection between the XUSB
+pad controller and the XUSB controller as "ports". This is confusing since
+"port" is typically used to denote the physical USB receptacle. The device
+tree binding in this document uses the term "port" to refer to the logical
+abstraction of the signals that are routed to a USB receptacle (i.e. a PHY
+for the USB signal, the VBUS power supply, the USB 2.0 companion port for
+USB 3.0 receptacles, ...).
+
+Required properties:
+--------------------
+- compatible: Must be:
+ - Tegra124: "nvidia,tegra124-xusb-padctl"
+ - Tegra132: "nvidia,tegra132-xusb-padctl", "nvidia,tegra124-xusb-padctl"
+- reg: Physical base address and length of the controller's registers.
+- resets: Must contain an entry for each entry in reset-names.
+- reset-names: Must include the following entries:
+ - "padctl"
+
+
+Pad nodes:
+==========
+
+A required child node named "pads" contains a list of subnodes, one for each
+of the pads exposed by the XUSB pad controller. Each pad may need additional
+resources that can be referenced in its pad node.
+
+The "status" property is used to enable or disable the use of a pad. If set
+to "disabled", the pad will not be used on the given board. In order to use
+the pad and any of its lanes, this property must be set to "okay".
+
+For Tegra124 and Tegra132, the following pads exist: usb2, ulpi, hsic, pcie
+and sata. No extra resources are required for operation of these pads.
+
+
+PHY nodes:
+==========
+
+Each pad node has a child named "lanes" that contains one or more children of
+its own, each representing one of the lanes controlled by the pad.
+
+Required properties:
+--------------------
+- status: Defines the operation status of the PHY. Valid values are:
+ - "disabled": the PHY is disabled
+ - "okay": the PHY is enabled
+- #phy-cells: Should be 0. Since each lane represents a single PHY, there is
+ no need for an additional specifier.
+- nvidia,function: The output function of the PHY. See below for a list of
+ valid functions per SoC generation.
+
+For Tegra124 and Tegra132, the list of valid PHY nodes is given below:
+- usb2: usb2-0, usb2-1, usb2-2
+ - functions: "snps", "xusb", "uart"
+- ulpi: ulpi-0
+ - functions: "snps", "xusb"
+- hsic: hsic-0, hsic-1
+ - functions: "snps", "xusb"
+- pcie: pcie-0, pcie-1, pcie-2, pcie-3, pcie-4
+ - functions: "pcie", "usb3-ss"
+- sata: sata-0
+ - functions: "usb3-ss", "sata"
+
+
+Port nodes:
+===========
+
+A required child node named "ports" contains a list of all the ports exposed
+by the XUSB pad controller. Per-port configuration is only required for USB.
+
+USB2 ports:
+-----------
+
+Required properties:
+- status: Defines the operation status of the port. Valid values are:
+ - "disabled": the port is disabled
+ - "okay": the port is enabled
+- mode: A string that determines the mode in which to run the port. Valid
+ values are:
+ - "host": for USB host mode
+ - "device": for USB device mode
+ - "otg": for USB OTG mode
+
+Optional properties:
+- nvidia,internal: A boolean property whose presence determines that a port
+ is internal. In the absence of this property the port is considered to be
+ external.
+- vbus-supply: phandle to a regulator supplying the VBUS voltage.
+
+ULPI ports:
+-----------
+
+Optional properties:
+- status: Defines the operation status of the port. Valid values are:
+ - "disabled": the port is disabled
+ - "okay": the port is enabled
+- nvidia,internal: A boolean property whose presence determines that a port
+ is internal. In the absence of this property the port is considered to be
+ external.
+- vbus-supply: phandle to a regulator supplying the VBUS voltage.
+
+HSIC ports:
+-----------
+
+Required properties:
+- status: Defines the operation status of the port. Valid values are:
+ - "disabled": the port is disabled
+ - "okay": the port is enabled
+
+Optional properties:
+- vbus-supply: phandle to a regulator supplying the VBUS voltage.
+
+Super-speed USB ports:
+----------------------
+
+Required properties:
+- status: Defines the operation status of the port. Valid values are:
+ - "disabled": the port is disabled
+ - "okay": the port is enabled
+- nvidia,usb2-companion: A single cell that specifies the physical port number
+ to map this super-speed USB port to. The range of valid port numbers varies
+ with the SoC generation:
+ - 0-2: for Tegra124 and Tegra132
+
+Optional properties:
+- nvidia,internal: A boolean property whose presence determines that a port
+ is internal. In the absence of this property the port is considered to be
+ external.
+
+For Tegra124 and Tegra132, the XUSB pad controller exposes the following
+ports:
+- 3x USB2: usb2-0, usb2-1, usb2-2
+- 1x ULPI: ulpi-0
+- 2x HSIC: hsic-0, hsic-1
+- 2x super-speed USB: usb3-0, usb3-1
+
+
+Examples:
+=========
+
+Tegra124 and Tegra132:
+----------------------
+
+SoC include:
+
+ padctl@7009f000 {
+ /* for Tegra124 */
+ compatible = "nvidia,tegra124-xusb-padctl";
+ /* for Tegra132 */
+ compatible = "nvidia,tegra132-xusb-padctl",
+ "nvidia,tegra124-xusb-padctl";
+ reg = <0x0 0x7009f000 0x0 0x1000>;
+ resets = <&tegra_car 142>;
+ reset-names = "padctl";
+
+ pads {
+ usb2 {
+ status = "disabled";
+
+ lanes {
+ usb2-0 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ usb2-1 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ usb2-2 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+ };
+ };
+
+ ulpi {
+ status = "disabled";
+
+ lanes {
+ ulpi-0 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+ };
+ };
+
+ hsic {
+ status = "disabled";
+
+ lanes {
+ hsic-0 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ hsic-1 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+ };
+ };
+
+ pcie {
+ status = "disabled";
+
+ lanes {
+ pcie-0 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ pcie-1 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ pcie-2 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ pcie-3 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+
+ pcie-4 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+ };
+ };
+
+ sata {
+ status = "disabled";
+
+ lanes {
+ sata-0 {
+ status = "disabled";
+ #phy-cells = <0>;
+ };
+ };
+ };
+ };
+
+ ports {
+ usb2-0 {
+ status = "disabled";
+ };
+
+ usb2-1 {
+ status = "disabled";
+ };
+
+ usb2-2 {
+ status = "disabled";
+ };
+
+ ulpi-0 {
+ status = "disabled";
+ };
+
+ hsic-0 {
+ status = "disabled";
+ };
+
+ hsic-1 {
+ status = "disabled";
+ };
+
+ usb3-0 {
+ status = "disabled";
+ };
+
+ usb3-1 {
+ status = "disabled";
+ };
+ };
+ };
+
+Board file:
+
+ padctl@7009f000 {
+ status = "okay";
+
+ pads {
+ usb2 {
+ status = "okay";
+
+ lanes {
+ usb2-0 {
+ nvidia,function = "xusb";
+ status = "okay";
+ };
+
+ usb2-1 {
+ nvidia,function = "xusb";
+ status = "okay";
+ };
+
+ usb2-2 {
+ nvidia,function = "xusb";
+ status = "okay";
+ };
+ };
+ };
+
+ pcie {
+ status = "okay";
+
+ lanes {
+ pcie-0 {
+ nvidia,function = "usb3-ss";
+ status = "okay";
+ };
+
+ pcie-2 {
+ nvidia,function = "pcie";
+ status = "okay";
+ };
+
+ pcie-4 {
+ nvidia,function = "pcie";
+ status = "okay";
+ };
+ };
+ };
+
+ sata {
+ status = "okay";
+
+ lanes {
+ sata-0 {
+ nvidia,function = "sata";
+ status = "okay";
+ };
+ };
+ };
+ };
+
+ ports {
+ /* Micro A/B */
+ usb2-0 {
+ status = "okay";
+ mode = "otg";
+ };
+
+ /* Mini PCIe */
+ usb2-1 {
+ status = "okay";
+ mode = "host";
+ };
+
+ /* USB3 */
+ usb2-2 {
+ status = "okay";
+ mode = "host";
+
+ vbus-supply = <&vdd_usb3_vbus>;
+ };
+
+ usb3-0 {
+ nvidia,port = <2>;
+ status = "okay";
+ };
+ };
+ };