usb: dwc3: gadget: Iterate only over valid endpoints

Make dwc3_gadget_resize_tx_fifos() iterate only over IN
endpoints that are actually present, based on the
num_in_eps parameter. This terminates the loop so as to
prevent dereferencing a potential NULL dwc->eps[i] where
i >= (num_in_eps + num_out_eps).
Signed-off-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -187,15 +187,12 @@ int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc)
 	 * improve this algorithm so that we better use the internal
 	 * FIFO space
 	 */
-	for (num = 0; num < DWC3_ENDPOINTS_NUM; num++) {
-		struct dwc3_ep	*dep = dwc->eps[num];
-		int		fifo_number = dep->number >> 1;
+	for (num = 0; num < dwc->num_in_eps; num++) {
+		/* bit0 indicates direction; 1 means IN ep */
+		struct dwc3_ep	*dep = dwc->eps[(num << 1) | 1];
 		int		mult = 1;
 		int		tmp;
 
-		if (!(dep->number & 1))
-			continue;
-
 		if (!(dep->flags & DWC3_EP_ENABLED))
 			continue;
 
@@ -224,8 +221,7 @@ int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc)
 		dev_vdbg(dwc->dev, "%s: Fifo Addr %04x Size %d\n",
 				dep->name, last_fifo_depth, fifo_size & 0xffff);
 
-		dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(fifo_number),
-				fifo_size);
+		dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(num), fifo_size);
 
 		last_fifo_depth += (fifo_size & 0xffff);
 	}