usb: dwc2: gadget: resume the core even if no gadget driver is bound.

When no gadget driver has been bound, at least re-initialize the core as
disconnected. It addresses the case when a device gets plugged-in later
(e.g. dwc2 switches to host). This way, the necessary low level init has
been done to switch to host mode.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Change-Id: Ic4c8b8a0bb57c0f6afab5ac613d47d8d2ae8c3df
Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/linux-stm32/+/461204
ACI: CITOOLS <MDG-smet-aci-reviews@list.st.com>

Author: Fabrice Gasnier

drivers/usb/dwc2/gadget.c

@@ -5320,19 +5320,19 @@ int dwc2_hsotg_resume(struct dwc2_hsotg *hsotg)
 	if (!hsotg->gadget_off_for_suspend)
 		return 0;
 
+	spin_lock_irqsave(&hsotg->lock, flags);
+	dwc2_hsotg_core_init_disconnected(hsotg, false);
 	if (hsotg->driver) {
 		dev_info(hsotg->dev, "resuming usb gadget %s\n",
 			 hsotg->driver->driver.name);
 
-		spin_lock_irqsave(&hsotg->lock, flags);
-		dwc2_hsotg_core_init_disconnected(hsotg, false);
 		if (hsotg->enabled) {
 			/* Enable ACG feature in device mode,if supported */
 			dwc2_enable_acg(hsotg);
 			dwc2_hsotg_core_connect(hsotg);
 		}
-		spin_unlock_irqrestore(&hsotg->lock, flags);
 	}
+	spin_unlock_irqrestore(&hsotg->lock, flags);
 
 	return 0;
 }