diff --git a/include/libopencm3/usb/usbd.h b/include/libopencm3/usb/usbd.h
index 95df82f2..a7c125a4 100644
--- a/include/libopencm3/usb/usbd.h
+++ b/include/libopencm3/usb/usbd.h
@@ -188,9 +188,6 @@ extern uint8_t usbd_ep_stall_get(usbd_device *usbd_dev, uint8_t addr);
  */
 extern void usbd_ep_nak_set(usbd_device *usbd_dev, uint8_t addr, uint8_t nak);
 
-/* Optional */
-extern void usbd_cable_connect(usbd_device *usbd_dev, uint8_t on);
-
 END_DECLS
 
 #endif