usb: dwc3: drop ev_buffs array

we will be using a single event buffer and that
renders ev_buffs array unnecessary. Let's remove it
in favor of a single pointer to a single event
buffer.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc3/core.c

@@ -204,7 +204,7 @@ static void dwc3_free_event_buffers(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
 
-	evt = dwc->ev_buffs[0];
+	evt = dwc->ev_buf;
 	if (evt)
 		dwc3_free_one_event_buffer(dwc, evt);
 }
@@ -221,17 +221,12 @@ static int dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned length)
 {
 	struct dwc3_event_buffer *evt;
 
-	dwc->ev_buffs = devm_kzalloc(dwc->dev, sizeof(*dwc->ev_buffs),
-			GFP_KERNEL);
-	if (!dwc->ev_buffs)
-		return -ENOMEM;
-
 	evt = dwc3_alloc_one_event_buffer(dwc, length);
 	if (IS_ERR(evt)) {
 		dev_err(dwc->dev, "can't allocate event buffer\n");
 		return PTR_ERR(evt);
 	}
-	dwc->ev_buffs[0] = evt;
+	dwc->ev_buf = evt;
 
 	return 0;
 }
@@ -246,7 +241,7 @@ static int dwc3_event_buffers_setup(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
 
-	evt = dwc->ev_buffs[0];
+	evt = dwc->ev_buf;
 	dwc3_trace(trace_dwc3_core,
 			"Event buf %p dma %08llx length %d\n",
 			evt->buf, (unsigned long long) evt->dma,
@@ -269,7 +264,7 @@ static void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
 
-	evt = dwc->ev_buffs[0];
+	evt = dwc->ev_buf;
 
 	evt->lpos = 0;
 

drivers/usb/dwc3/core.h

@@ -753,7 +753,7 @@ struct dwc3 {
 	struct platform_device	*xhci;
 	struct resource		xhci_resources[DWC3_XHCI_RESOURCES_NUM];
 
-	struct dwc3_event_buffer **ev_buffs;
+	struct dwc3_event_buffer *ev_buf;
 	struct dwc3_ep		*eps[DWC3_ENDPOINTS_NUM];
 
 	struct usb_gadget	gadget;

drivers/usb/dwc3/gadget.c

@@ -2609,7 +2609,7 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc)
 	int left;
 	u32 reg;
 
-	evt = dwc->ev_buffs[0];
+	evt = dwc->ev_buf;
 	left = evt->count;
 
 	if (!(evt->flags & DWC3_EVENT_PENDING))
@@ -2668,7 +2668,7 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3 *dwc)
 	u32 count;
 	u32 reg;
 
-	evt = dwc->ev_buffs[0];
+	evt = dwc->ev_buf;
 
 	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
 	count &= DWC3_GEVNTCOUNT_MASK;