arm64: dts: ti: k3-j7200-common-proc-board: Add USB support

The board uses lane 3 of SERDES for USB. Set the mux
accordingly.

The USB controller and EVM supports super-speed for USB0
on the Type-C port. However, the SERDES has a limitation
that upto 2 protocols can be used at a time. The SERDES is
wired for PCIe, QSGMII and USB super-speed. It has been
chosen to use PCI2 and QSGMII as default. So restrict
USB0 to high-speed mode.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200930122032.23481-7-rogerq@ti.com

arch/arm64/boot/dts/ti/k3-j7200-common-proc-board.dts

@@ -69,6 +69,12 @@
 			J721E_IOPAD(0xe4, PIN_INPUT, 8) /* (V1) TIMER_IO0.MMC1_SDCD */
 		>;
 	};
+
+	main_usbss0_pins_default: main-usbss0-pins-default {
+		pinctrl-single,pins = <
+			J721E_IOPAD(0x120, PIN_OUTPUT, 0) /* (T4) USB0_DRVVBUS */
+		>;
+	};
 };
 
 &wkup_uart0 {
@@ -191,3 +197,19 @@
 	idle-states = <J7200_SERDES0_LANE0_PCIE1_LANE0>, <J7200_SERDES0_LANE1_PCIE1_LANE1>,
 		      <J7200_SERDES0_LANE2_QSGMII_LANE1>, <J7200_SERDES0_LANE3_IP4_UNUSED>;
 };
+
+&usb_serdes_mux {
+	idle-states = <1>; /* USB0 to SERDES lane 3 */
+};
+
+&usbss0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_usbss0_pins_default>;
+	ti,vbus-divider;
+	ti,usb2-only;
+};
+
+&usb0 {
+	dr_mode = "otg";
+	maximum-speed = "high-speed";
+};