diff --git a/sys/sys/bus.h b/sys/sys/bus.h
index 973f284a790..fa5ada3867b 100644
--- a/sys/sys/bus.h
+++ b/sys/sys/bus.h
@@ -702,6 +702,7 @@ void	bus_data_generation_update(void);
 #define	BUS_PASS_INTERRUPT	40	/* Interrupt controllers. */
 #define	BUS_PASS_TIMER		50	/* Timers and clocks. */
 #define	BUS_PASS_SCHEDULER	60	/* Start scheduler. */
+#define	BUS_PASS_SUPPORTDEV	100000	/* Drivers which support DEFAULT drivers. */
 #define	BUS_PASS_DEFAULT	__INT_MAX /* Everything else. */
 
 #define	BUS_PASS_ORDER_FIRST	0