usb: dwc3: ep0: fix setup_packet_pending initialization

It just ocurred to me that dwc3 already gives a
really hint of when a setup packet is pending and
that's the SETUP_PENDING TRB Status for EP0 IRQs.

Fix setup_packet_pending initialization based on
that. While at that, also make sure the comment in
gadget.c matches what code is doing.
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/ep0.c

@@ -817,6 +817,8 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc,
 
 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
+		dwc->setup_packet_pending = true;
+
 		dwc3_trace(trace_dwc3_ep0, "Setup Pending received");
 
 		if (r)
@@ -916,8 +918,10 @@ static void dwc3_ep0_complete_status(struct dwc3 *dwc,
 	}
 
 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
-	if (status == DWC3_TRBSTS_SETUP_PENDING)
+	if (status == DWC3_TRBSTS_SETUP_PENDING) {
+		dwc->setup_packet_pending = true;
 		dwc3_trace(trace_dwc3_ep0, "Setup Pending received");
+	}
 
 	dwc->ep0state = EP0_SETUP_PHASE;
 	dwc3_ep0_out_start(dwc);
@@ -1063,8 +1067,6 @@ static void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
 		const struct dwc3_event_depevt *event)
 {
-	dwc->setup_packet_pending = true;
-
 	switch (event->status) {
 	case DEPEVT_STATUS_CONTROL_DATA:
 		dwc3_trace(trace_dwc3_ep0, "Control Data");

drivers/usb/dwc3/gadget.c

@@ -2230,8 +2230,8 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
 	 *
 	 * Our suggested workaround is to follow the Disconnect
 	 * Event steps here, instead, based on a setup_packet_pending
-	 * flag. Such flag gets set whenever we have a XferNotReady
-	 * event on EP0 and gets cleared on XferComplete for the
+	 * flag. Such flag gets set whenever we have a SETUP_PENDING
+	 * status for EP0 TRBs and gets cleared on XferComplete for the
 	 * same endpoint.
 	 *
 	 * Refers to: