usb: chipidea: introduce CI_HDRC_CONTROLLER_VBUS_EVENT glue layer use

Some vendors glue layer need to handle some events for vbus, eg,
some i.mx platforms (imx7d, imx8mm, imx8mn, etc) needs vbus event
to handle charger detection, its charger detection is finished at
glue layer code, but not at USB PHY driver.
Signed-off-by: Peter Chen <peter.chen@nxp.com>

drivers/usb/chipidea/udc.c

@@ -1561,6 +1561,7 @@ static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
 {
 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
 	unsigned long flags;
+	int ret = 0;
 
 	spin_lock_irqsave(&ci->lock, flags);
 	ci->vbus_active = is_active;
@@ -1570,10 +1571,14 @@ static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
 		usb_phy_set_charger_state(ci->usb_phy, is_active ?
 			USB_CHARGER_PRESENT : USB_CHARGER_ABSENT);
 
+	if (ci->platdata->notify_event)
+		ret = ci->platdata->notify_event(ci,
+				CI_HDRC_CONTROLLER_VBUS_EVENT);
+
 	if (ci->driver)
 		ci_hdrc_gadget_connect(_gadget, is_active);
 
-	return 0;
+	return ret;
 }
 
 static int ci_udc_wakeup(struct usb_gadget *_gadget)

include/linux/usb/chipidea.h

@@ -67,6 +67,7 @@ struct ci_hdrc_platform_data {
 #define CI_HDRC_CONTROLLER_STOPPED_EVENT	1
 #define CI_HDRC_IMX_HSIC_ACTIVE_EVENT		2
 #define CI_HDRC_IMX_HSIC_SUSPEND_EVENT		3
+#define CI_HDRC_CONTROLLER_VBUS_EVENT		4
 	int	(*notify_event) (struct ci_hdrc *ci, unsigned event);
 	struct regulator	*reg_vbus;
 	struct usb_otg_caps	ci_otg_caps;