- * @param port Pointer to port structure.
- * @param usb_vid Pointer to variable to store USB VID.
- * @param usb_pid Pointer to variable to store USB PID
+ * @param[in] port Pointer to a port structure. Must not be NULL.
+ * @param[out] usb_vid Pointer to a variable to store the USB VID.
+ * Can be NULL (in that case it will be ignored).
+ * @param[out] usb_pid Pointer to a variable to store the USB PID.
+ * Can be NULL (in that case it will be ignored).