usb-core: Make usb_free_streams return an error

The hcd-driver free_streams method can return an error, so lets properly
propagate that.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hcd.c

@@ -2075,8 +2075,11 @@ EXPORT_SYMBOL_GPL(usb_alloc_streams);
  *
  * Reverts a group of bulk endpoints back to not using stream IDs.
  * Can fail if we are given bad arguments, or HCD is broken.
+ *
+ * Return: On success, the number of allocated streams. On failure, a negative
+ * error code.
  */
-void usb_free_streams(struct usb_interface *interface,
+int usb_free_streams(struct usb_interface *interface,
 		struct usb_host_endpoint **eps, unsigned int num_eps,
 		gfp_t mem_flags)
 {
@@ -2087,14 +2090,14 @@ void usb_free_streams(struct usb_interface *interface,
 	dev = interface_to_usbdev(interface);
 	hcd = bus_to_hcd(dev->bus);
 	if (dev->speed != USB_SPEED_SUPER)
-		return;
+		return -EINVAL;
 
 	/* Streams only apply to bulk endpoints. */
 	for (i = 0; i < num_eps; i++)
 		if (!eps[i] || !usb_endpoint_xfer_bulk(&eps[i]->desc))
-			return;
+			return -EINVAL;
 
-	hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
+	return hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
 }
 EXPORT_SYMBOL_GPL(usb_free_streams);
 

include/linux/usb.h

@@ -702,7 +702,7 @@ extern int usb_alloc_streams(struct usb_interface *interface,
 		unsigned int num_streams, gfp_t mem_flags);
 
 /* Reverts a group of bulk endpoints back to not using stream IDs. */
-extern void usb_free_streams(struct usb_interface *interface,
+extern int usb_free_streams(struct usb_interface *interface,
 		struct usb_host_endpoint **eps, unsigned int num_eps,
 		gfp_t mem_flags);