u-boot/doc/device-tree-bindings/phy/phy-mtk-tphy.txt

MediaTek T-PHY binding
--------------------------

T-phy controller supports physical layer functionality for a number of
controllers on MediaTek SoCs, such as, USB2.0, USB3.0, PCIe, and SATA.

Required properties (controller (parent) node):
 - compatible	: should be one of
		  "mediatek,generic-tphy-v1"
 - clocks	: (deprecated, use port's clocks instead) a list of phandle +
		  clock-specifier pairs, one for each entry in clock-names
 - clock-names	: (deprecated, use port's one instead) must contain
		  "u3phya_ref": for reference clock of usb3.0 analog phy.

Required nodes	: a sub-node is required for each port the controller
		  provides. Address range information including the usual
		  'reg' property is used inside these nodes to describe
		  the controller's topology.

Optional properties (controller (parent) node):
 - reg		: offset and length of register shared by multiple ports,
		  exclude port's private register.
 - mediatek,src-ref-clk-mhz	: frequency of reference clock for slew rate
		  calibrate
 - mediatek,src-coef	: coefficient for slew rate calibrate, depends on
		  SoC process

Required properties (port (child) node):
- reg		: address and length of the register set for the port.
- clocks	: a list of phandle + clock-specifier pairs, one for each
		  entry in clock-names
- clock-names	: must contain
		  "ref": 48M reference clock for HighSpeed analog phy; and 26M
			reference clock for SuperSpeed analog phy, sometimes is
			24M, 25M or 27M, depended on platform.
- #phy-cells	: should be 1 (See second example)
		  cell after port phandle is phy type from:
			- PHY_TYPE_USB2
			- PHY_TYPE_USB3
			- PHY_TYPE_PCIE
			- PHY_TYPE_SATA

Example:

	u3phy2: usb-phy@1a244000 {
		compatible = "mediatek,generic-tphy-v1";
		reg = <0x1a244000 0x0700>;
		#address-cells = <1>;
		#size-cells = <1>;
		ranges;
		status = "disabled";

		u2port1: usb-phy@1a244800 {
			reg = <0x1a244800 0x0100>;
			clocks = <&topckgen CLK_TOP_USB_PHY48M>;
			clock-names = "ref";
			#phy-cells = <1>;
			status = "okay";
		};

		u3port1: usb-phy@1a244900 {
			reg = <0x1a244900 0x0700>;
			clocks = <&clk26m>;
			clock-names = "ref";
			#phy-cells = <1>;
			status = "okay";
		};
	};

Specifying phy control of devices
---------------------------------

Device nodes should specify the configuration required in their "phys"
property, containing a phandle to the phy port node and a device type;
phy-names for each port are optional.

Example:

#include <dt-bindings/phy/phy.h>

usb30: usb@11270000 {
	...
	phys = <&u2port0 PHY_TYPE_USB2>, <&u3port0 PHY_TYPE_USB3>;
	phy-names = "usb2-0", "usb3-0";
	...
};