diff --git a/arch/arm/mach-s3c2416/irq.c b/arch/arm/mach-s3c2416/irq.c
index 784485777896..00174daf1526 100644
--- a/arch/arm/mach-s3c2416/irq.c
+++ b/arch/arm/mach-s3c2416/irq.c
@@ -172,8 +172,7 @@ static void s3c2416_irq_demux_uart3(unsigned int irq, struct irq_desc *desc)
 }
 
 #define INTMSK_UART3	(1UL << (IRQ_S3C2443_UART3 - IRQ_EINT0))
-#define SUBMSK_UART3	(0xf << (IRQ_S3C2443_RX3 - S3C2410_IRQSUB(0)))
-
+#define SUBMSK_UART3	(0x7 << (IRQ_S3C2443_RX3 - S3C2410_IRQSUB(0)))
 
 static void s3c2416_irq_uart3_mask(unsigned int irqno)
 {
diff --git a/arch/arm/mach-s3c2443/irq.c b/arch/arm/mach-s3c2443/irq.c
index df2b8db49818..893424767ce1 100644
--- a/arch/arm/mach-s3c2443/irq.c
+++ b/arch/arm/mach-s3c2443/irq.c
@@ -170,8 +170,7 @@ static void s3c2443_irq_demux_uart3(unsigned int irq, struct irq_desc *desc)
 }
 
 #define INTMSK_UART3	(1UL << (IRQ_S3C2443_UART3 - IRQ_EINT0))
-#define SUBMSK_UART3	(0xf << (IRQ_S3C2443_RX3 - S3C2410_IRQSUB(0)))
-
+#define SUBMSK_UART3	(0x7 << (IRQ_S3C2443_RX3 - S3C2410_IRQSUB(0)))
 
 static void s3c2443_irq_uart3_mask(unsigned int irqno)
 {