diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 717e376795e4c7f7f2ed258f770ecd512bab7fba..3bcf3346658772e1a8efce24fd50072f5cbcf210 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -625,7 +625,7 @@ int usb_serial_probe(struct usb_interface *interface,
 	struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
 	struct usb_serial_driver *type = NULL;
 	int retval;
-	int minor;
+	unsigned int minor;
 	int buffer_size;
 	int i;
 	int num_interrupt_in = 0;