usb: dwc3: ep0: Clear started flag on completion

commit 2d7b78f5 upstream.

Clear ep0's DWC3_EP_TRANSFER_STARTED flag if the END_TRANSFER command is
completed. Otherwise, we can't start control transfer again after
END_TRANSFER.

Cc: stable@vger.kernel.org
Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/dwc3/ep0.c

@@ -1110,6 +1110,9 @@ static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
 void dwc3_ep0_interrupt(struct dwc3 *dwc,
 		const struct dwc3_event_depevt *event)
 {
+	struct dwc3_ep	*dep = dwc->eps[event->endpoint_number];
+	u8		cmd;
+
 	switch (event->endpoint_event) {
 	case DWC3_DEPEVT_XFERCOMPLETE:
 		dwc3_ep0_xfer_complete(dwc, event);
@@ -1122,7 +1125,12 @@ void dwc3_ep0_interrupt(struct dwc3 *dwc,
 	case DWC3_DEPEVT_XFERINPROGRESS:
 	case DWC3_DEPEVT_RXTXFIFOEVT:
 	case DWC3_DEPEVT_STREAMEVT:
+		break;
 	case DWC3_DEPEVT_EPCMDCMPLT:
+		cmd = DEPEVT_PARAMETER_CMD(event->parameters);
+
+		if (cmd == DWC3_DEPCMD_ENDTRANSFER)
+			dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
 		break;
 	}
 }