usb: dwc3: remove num_event_buffers

We never, ever route any of the other event buffers
so we might as well drop support for them.

Until someone has a real, proper benefit for
multiple event buffers, we will rely on a single
one. This also helps reduce memory footprint of
dwc3.ko which won't allocate memory for the extra
event buffers.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 67d183a..9e5c57c7 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -203,13 +203,10 @@
 static void dwc3_free_event_buffers(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
-	int i;
 
-	for (i = 0; i < dwc->num_event_buffers; i++) {
-		evt = dwc->ev_buffs[i];
-		if (evt)
-			dwc3_free_one_event_buffer(dwc, evt);
-	}
+	evt = dwc->ev_buffs[0];
+	if (evt)
+		dwc3_free_one_event_buffer(dwc, evt);
 }
 
 /**
@@ -222,27 +219,19 @@
  */
 static int dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned length)
 {
-	int			num;
-	int			i;
+	struct dwc3_event_buffer *evt;
 
-	num = DWC3_NUM_INT(dwc->hwparams.hwparams1);
-	dwc->num_event_buffers = num;
-
-	dwc->ev_buffs = devm_kzalloc(dwc->dev, sizeof(*dwc->ev_buffs) * num,
+	dwc->ev_buffs = devm_kzalloc(dwc->dev, sizeof(*dwc->ev_buffs),
 			GFP_KERNEL);
 	if (!dwc->ev_buffs)
 		return -ENOMEM;
 
-	for (i = 0; i < num; i++) {
-		struct dwc3_event_buffer	*evt;
-
-		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[i] = evt;
+	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;
 
 	return 0;
 }
@@ -256,25 +245,22 @@
 static int dwc3_event_buffers_setup(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
-	int				n;
 
-	for (n = 0; n < dwc->num_event_buffers; n++) {
-		evt = dwc->ev_buffs[n];
-		dwc3_trace(trace_dwc3_core,
-				"Event buf %p dma %08llx length %d\n",
-				evt->buf, (unsigned long long) evt->dma,
-				evt->length);
+	evt = dwc->ev_buffs[0];
+	dwc3_trace(trace_dwc3_core,
+			"Event buf %p dma %08llx length %d\n",
+			evt->buf, (unsigned long long) evt->dma,
+			evt->length);
 
-		evt->lpos = 0;
+	evt->lpos = 0;
 
-		dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(n),
-				lower_32_bits(evt->dma));
-		dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(n),
-				upper_32_bits(evt->dma));
-		dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(n),
-				DWC3_GEVNTSIZ_SIZE(evt->length));
-		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(n), 0);
-	}
+	dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(0),
+			lower_32_bits(evt->dma));
+	dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(0),
+			upper_32_bits(evt->dma));
+	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0),
+			DWC3_GEVNTSIZ_SIZE(evt->length));
+	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 0);
 
 	return 0;
 }
@@ -282,19 +268,16 @@
 static void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
 {
 	struct dwc3_event_buffer	*evt;
-	int				n;
 
-	for (n = 0; n < dwc->num_event_buffers; n++) {
-		evt = dwc->ev_buffs[n];
+	evt = dwc->ev_buffs[0];
 
-		evt->lpos = 0;
+	evt->lpos = 0;
 
-		dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(n), 0);
-		dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(n), 0);
-		dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(n), DWC3_GEVNTSIZ_INTMASK
-				| DWC3_GEVNTSIZ_SIZE(0));
-		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(n), 0);
-	}
+	dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(0), 0);
+	dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(0), 0);
+	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), DWC3_GEVNTSIZ_INTMASK
+			| DWC3_GEVNTSIZ_SIZE(0));
+	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 0);
 }
 
 static int dwc3_alloc_scratch_buffers(struct dwc3 *dwc)