-/* Attempts to add 'netdev' as a port on 'dpif'. If successful, returns 0 and
- * sets '*port_nop' to the new port's port number (if 'port_nop' is non-null).
- * On failure, returns a positive errno value and sets '*port_nop' to
- * UINT16_MAX (if 'port_nop' is non-null). */
+/* Attempts to add 'netdev' as a port on 'dpif'. If 'port_nop' is
+ * non-null and its value is not UINT16_MAX, then attempts to use the
+ * value as the port number.
+ *
+ * If successful, returns 0 and sets '*port_nop' to the new port's port
+ * number (if 'port_nop' is non-null). On failure, returns a positive
+ * errno value and sets '*port_nop' to UINT16_MAX (if 'port_nop' is
+ * non-null). */