diff --git a/sys/modules/uart/Makefile b/sys/modules/uart/Makefile
index 9fc15c098e04..4de0e9aeb48e 100644
--- a/sys/modules/uart/Makefile
+++ b/sys/modules/uart/Makefile
@@ -10,7 +10,7 @@ KMOD=	uart
 SRCS=	uart_bus_acpi.c ${uart_bus_ebus} uart_bus_isa.c uart_bus_pccard.c \
 	uart_bus_pci.c uart_bus_puc.c uart_core.c uart_cpu_${MACHINE}.c \
 	uart_dev_i8251.c uart_dev_ns8250.c uart_dev_sab82532.c \
-	uart_dev_z8530.c uart_if.c uart_tty.c
+	uart_dev_z8530.c uart_if.c uart_subr.c uart_tty.c
 SRCS+=	bus_if.h device_if.h isa_if.h pci_if.h uart_if.h power_if.h card_if.h
 
 .include <bsd.kmod.mk>