diff --git a/src/add-ons/kernel/drivers/ports/usb_serial/driver.h b/src/add-ons/kernel/drivers/ports/usb_serial/driver.h
index 311e330b76..61792ca60a 100644
--- a/src/add-ons/kernel/drivers/ports/usb_serial/driver.h
+++ b/src/add-ons/kernel/drivers/ports/usb_serial/driver.h
@@ -45,13 +45,17 @@ typedef struct _s_usb_serial_line_coding{
 #define  CLS_LINE_RTS  0x0002
 
 /* "forgotten" attributes etc ...*/
+#ifndef USB_EP_ADDR_DIR_IN
 #define USB_EP_ADDR_DIR_IN   0x80
 #define USB_EP_ADDR_DIR_OUT  0x00
+#endif
 
+#ifndef USB_EP_ATTR_CONTROL
 #define USB_EP_ATTR_CONTROL      0x00
 #define USB_EP_ATTR_ISOCHRONOUS  0x01
 #define USB_EP_ATTR_BULK         0x02 
 #define USB_EP_ATTR_INTERRUPT    0x03 
+#endif
 /* USB class - communication devices */
 #define USB_DEV_CLASS_COMM     0x02