diff --git a/drivers/serial/mcf.c b/drivers/serial/mcf.c
index b9f7dfe6c5d53be0cabdd8d47dca79dfc359d123..b5aaef965f24e904e179a4a579fa4bcafbf92809 100644
--- a/drivers/serial/mcf.c
+++ b/drivers/serial/mcf.c
@@ -445,7 +445,7 @@ static const struct uart_ops mcf_uart_ops = {
 	.verify_port	= mcf_verify_port,
 };
 
-static struct mcf_uart mcf_ports[3];
+static struct mcf_uart mcf_ports[4];
 
 #define	MCF_MAXPORTS	ARRAY_SIZE(mcf_ports)