usb: dwc3: gadget: add dwc3_request status tracking

This patch starts tracking dwc3_request status. A following patch will
build on top of this to prevent a request from being queued twice.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc3/core.h

@@ -863,6 +863,7 @@ struct dwc3_hwparams {
  * @num_pending_sgs: counter to pending sgs
  * @num_queued_sgs: counter to the number of sgs which already got queued
  * @remaining: amount of data remaining
+ * @status: internal dwc3 request status tracking
  * @epnum: endpoint number to which this request refers
  * @trb: pointer to struct dwc3_trb
  * @trb_dma: DMA address of @trb
@@ -883,6 +884,14 @@ struct dwc3_request {
 	unsigned		num_pending_sgs;
 	unsigned int		num_queued_sgs;
 	unsigned		remaining;
+
+	unsigned int		status;
+#define DWC3_REQUEST_STATUS_QUEUED	0
+#define DWC3_REQUEST_STATUS_STARTED	1
+#define DWC3_REQUEST_STATUS_CANCELLED	2
+#define DWC3_REQUEST_STATUS_COMPLETED	3
+#define DWC3_REQUEST_STATUS_UNKNOWN	-1
+
 	u8			epnum;
 	struct dwc3_trb		*trb;
 	dma_addr_t		trb_dma;

drivers/usb/dwc3/gadget.c

@@ -209,6 +209,7 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 	struct dwc3			*dwc = dep->dwc;
 
 	dwc3_gadget_del_and_unmap_request(dep, req, status);
+	req->status = DWC3_REQUEST_STATUS_COMPLETED;
 
 	spin_unlock(&dwc->lock);
 	usb_gadget_giveback_request(&dep->endpoint, &req->request);
@@ -847,6 +848,7 @@ static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
 	req->direction	= dep->direction;
 	req->epnum	= dep->number;
 	req->dep	= dep;
+	req->status	= DWC3_REQUEST_STATUS_UNKNOWN;
 
 	trace_dwc3_alloc_request(req);
 
@@ -1443,6 +1445,7 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
 	trace_dwc3_ep_queue(req);
 
 	list_add_tail(&req->list, &dep->pending_list);
+	req->status = DWC3_REQUEST_STATUS_QUEUED;
 
 	/*
 	 * NOTICE: Isochronous endpoints should NEVER be prestarted. We must

drivers/usb/dwc3/gadget.h

@@ -76,6 +76,7 @@ static inline void dwc3_gadget_move_started_request(struct dwc3_request *req)
 	struct dwc3_ep		*dep = req->dep;
 
 	req->started = true;
+	req->status = DWC3_REQUEST_STATUS_STARTED;
 	list_move_tail(&req->list, &dep->started_list);
 }
 
@@ -91,6 +92,7 @@ static inline void dwc3_gadget_move_cancelled_request(struct dwc3_request *req)
 	struct dwc3_ep		*dep = req->dep;
 
 	req->started = false;
+	req->status = DWC3_REQUEST_STATUS_CANCELLED;
 	list_move_tail(&req->list, &dep->cancelled_list);
 }