usb: dwc3: Add Google Tensor SoC DWC3 glue driver

Add support for the DWC3 USB controller found on Google Tensor G5
(codename: laguna). The controller features dual-role functionality
and hibernation.

The primary focus is implementing hibernation support in host mode,
enabling the controller to enter a low-power state (D3). This is
particularly relevant during system power state transition and
runtime power management for power efficiency.
Highlights:
- Align suspend callback with dwc3_suspend_common() for deciding
  between a full teardown and hibernation in host mode.
- Integration with `psw` (power switchable) and `top` power domains,
  managing their states and device links to support hibernation.
- A notifier callback dwc3_google_usb_psw_pd_notifier() for
  `psw` power domain events to manage controller state
  transitions to/from D3.
- Coordination of the `non_sticky` reset during power state
  transitions, asserting it on D3 entry and deasserting on D0 entry
  in hibernation scenario.
- Handling of high-speed and super-speed PME interrupts
  that are generated by remote wakeup during hibernation.

Co-developed-by: Joy Chakraborty <joychakr@google.com>
Signed-off-by: Joy Chakraborty <joychakr@google.com>
Co-developed-by: Naveen Kumar <mnkumar@google.com>
Signed-off-by: Naveen Kumar <mnkumar@google.com>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Roy Luo <royluo@google.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://patch.msgid.link/20251218-controller-v10-2-4047c9077274@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

MAINTAINERS

@@ -10727,6 +10727,7 @@ F:	arch/arm64/boot/dts/exynos/google/
 F:	drivers/clk/samsung/clk-gs101.c
 F:	drivers/soc/samsung/gs101-pmu.c
 F:	drivers/phy/samsung/phy-gs101-ufs.c
+F:	drivers/usb/dwc3/dwc3-google.c
 F:	include/dt-bindings/clock/google,gs101*
 K:	[gG]oogle.?[tT]ensor
 

drivers/usb/dwc3/Kconfig

@@ -211,4 +211,15 @@ config USB_DWC3_APPLE
 	  mode on these machines.
 	  Say 'Y' or 'M' if you have such device.
 
+config USB_DWC3_GOOGLE
+	tristate "Google Platform"
+	help
+	  Support the DesignWare Core USB3 IP found on Google Tensor SoCs,
+	  starting with the G5 generation (Laguna). This driver includes
+	  support for hibernation in host mode.
+	  Say 'Y' or 'M' if you have one such device.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called dwc3-google.ko.
+
 endif

drivers/usb/dwc3/Makefile

@@ -59,3 +59,4 @@ obj-$(CONFIG_USB_DWC3_XILINX)		+= dwc3-xilinx.o
 obj-$(CONFIG_USB_DWC3_OCTEON)		+= dwc3-octeon.o
 obj-$(CONFIG_USB_DWC3_RTK)		+= dwc3-rtk.o
 obj-$(CONFIG_USB_DWC3_GENERIC_PLAT)	+= dwc3-generic-plat.o
+obj-$(CONFIG_USB_DWC3_GOOGLE)		+= dwc3-google.o