usb: dwc3: core: fix order of PM runtime calls

Currently, we disable pm_runtime before all register
accesses are done, this is dangerous and might lead
to abort exceptions due to the driver trying to access
a register which is clocked by a clock which was long
gated.

Fix that by moving pm_runtime_put_sync() and pm_runtime_disable()
as the last thing we do before returning from our ->remove()
method.

Fixes: 72246da4 (usb: Introduce DesignWare USB3 DRD Driver)
Cc: <stable@vger.kernel.org> # v3.2+
Signed-off-by: Felipe Balbi <balbi@ti.com>

(cherry picked from commit fed33afc)
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

drivers/usb/dwc3/core.c

@@ -597,6 +597,28 @@ static int dwc3_remove(struct platform_device *pdev)
 	dwc3_free_event_buffers(dwc);
 	dwc3_core_exit(dwc);
 
+	dwc3_debugfs_exit(dwc);
+
+	switch (dwc->dr_mode) {
+	case USB_DR_MODE_PERIPHERAL:
+		dwc3_gadget_exit(dwc);
+		break;
+	case USB_DR_MODE_HOST:
+		dwc3_host_exit(dwc);
+		break;
+	case USB_DR_MODE_OTG:
+		dwc3_host_exit(dwc);
+		dwc3_gadget_exit(dwc);
+		break;
+	default:
+		/* do nothing */
+		break;
+	}
+
+	dwc3_event_buffers_cleanup(dwc);
+	dwc3_free_event_buffers(dwc);
+	dwc3_core_exit(dwc);
+
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);