[PATCH] dwc3: gadget: Implement the suspend entry event handler

[Baolin Wang <baolin.wang@linaro.org>]

It had changed to be suspend event for BIT6 in DEVT register from
version 2.30a and above. Thus this patch introduces one suspend
event handler to handle the suspend event.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/usb/dwc3/gadget.c |   26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 8e4a1b1..9b14ecc 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2595,6 +2595,17 @@ static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
 	dwc->link_state = next;
 }
 
+static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
+					  unsigned int evtinfo)
+{
+	enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
+
+	if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
+		dwc3_suspend_gadget(dwc);
+
+	dwc->link_state = next;
+}
+
 static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
 		unsigned int evtinfo)
 {
@@ -2646,7 +2657,20 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc,
 		dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
 		break;
 	case DWC3_DEVICE_EVENT_EOPF:
-		dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
+		/* It changed to be suspend event for version 2.30a and above */
+		if (dwc->revision < DWC3_REVISION_230A) {
+			dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
+		} else {
+			dwc3_trace(trace_dwc3_gadget, "U3/L1-L2 Suspend Event");
+
+			/*
+			 * Ignore suspend event until the gadget enters into
+			 * USB_STATE_CONFIGURED state.
+			 */
+			if (dwc->gadget.state >= USB_STATE_CONFIGURED)
+				dwc3_gadget_suspend_interrupt(dwc,
+						event->event_info);
+		}
 		break;
 	case DWC3_DEVICE_EVENT_SOF:
 		dwc3_trace(trace_dwc3_gadget, "Start of Periodic Frame");
-- 
1.7.9.5