usb: dwc3: gadget: pre-start Stream transfers when they're queued

we need to pre-start stream transfers otherwise we
will never know when to start them.
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -1129,6 +1129,23 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
 		return ret;
 	}
 
+	/*
+	 * 4. Stream Capable Bulk Endpoints. We need to start the transfer
+	 * right away, otherwise host will not know we have streams to be
+	 * handled.
+	 */
+	if (dep->stream_capable) {
+		int	ret;
+
+		ret = __dwc3_gadget_kick_transfer(dep, 0, true);
+		if (ret && ret != -EBUSY) {
+			struct dwc3	*dwc = dep->dwc;
+
+			dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
+					dep->name);
+		}
+	}
+
 	return 0;
 }