usb: dwc3: keep susphy enabled during exit to avoid controller faults

On some platforms, switching USB roles from host to device can trigger
controller faults due to premature PHY power-down. This occurs when the
PHY is disabled too early during teardown, causing synchronization
issues between the PHY and controller.

Keep susphy enabled during dwc3_host_exit() and dwc3_gadget_exit()
ensures the PHY remains in a low-power state capable of handling
required commands during role switch.

Cc: stable <stable@kernel.org>
Fixes: 6d73572 ("usb: dwc3: core: Prevent phy suspend during init")
Suggested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Udipto Goswami <udipto.goswami@oss.qualcomm.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://patch.msgid.link/20251126054221.120638-1-udipto.goswami@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Udipto Goswami

drivers/usb/dwc3/gadget.c

@@ -4826,7 +4826,7 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
 	if (!dwc->gadget)
 		return;
 
-	dwc3_enable_susphy(dwc, false);
+	dwc3_enable_susphy(dwc, true);
 	usb_del_gadget(dwc->gadget);
 	dwc3_gadget_free_endpoints(dwc);
 	usb_put_gadget(dwc->gadget);

drivers/usb/dwc3/host.c

@@ -227,7 +227,7 @@ void dwc3_host_exit(struct dwc3 *dwc)
 	if (dwc->sys_wakeup)
 		device_init_wakeup(&dwc->xhci->dev, false);
 
-	dwc3_enable_susphy(dwc, false);
+	dwc3_enable_susphy(dwc, true);
 	platform_device_unregister(dwc->xhci);
 	dwc->xhci = NULL;
 }