diff --git a/arch/arm/mach-s3c2412/irq.c b/arch/arm/mach-s3c2412/irq.c
index f0d6682..e9d0c76 100644
--- a/arch/arm/mach-s3c2412/irq.c
+++ b/arch/arm/mach-s3c2412/irq.c
@@ -38,6 +38,9 @@
 #include <asm/plat-s3c24xx/irq.h>
 #include <asm/plat-s3c24xx/pm.h>
 
+#define INTMSK(start, end) ((1 << ((end) + 1 - (start))) - 1)
+#define INTMSK_SUB(start, end) (INTMSK(start, end) << ((start - S3C2410_IRQSUB(0))))
+
 /* the s3c2412 changes the behaviour of IRQ_EINT0 through IRQ_EINT3 by
  * having them turn up in both the INT* and the EINT* registers. Whilst
  * both show the status, they both now need to be acked when the IRQs
@@ -105,6 +108,51 @@
 	.set_type  = s3c_irqext_type,
 };
 
+#define INTBIT(x)	(1 << ((x) - S3C2410_IRQSUB(0)))
+
+/* CF and SDI sub interrupts */
+
+static void s3c2412_irq_demux_cfsdi(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned int subsrc, submsk;
+
+	subsrc = __raw_readl(S3C2410_SUBSRCPND);
+	submsk = __raw_readl(S3C2410_INTSUBMSK);
+
+	subsrc  &= ~submsk;
+
+	if (subsrc & INTBIT(IRQ_S3C2412_SDI))
+		desc_handle_irq(IRQ_S3C2412_SDI, irq_desc + IRQ_S3C2412_SDI);
+
+	if (subsrc & INTBIT(IRQ_S3C2412_CF))
+		desc_handle_irq(IRQ_S3C2412_CF, irq_desc + IRQ_S3C2412_CF);
+}
+
+#define INTMSK_CFSDI	(1UL << (IRQ_S3C2412_CFSDI - IRQ_EINT0))
+#define SUBMSK_CFSDI	INTMSK_SUB(IRQ_S3C2412_SDI, IRQ_S3C2412_CF)
+
+static void s3c2412_irq_cfsdi_mask(unsigned int irqno)
+{
+	s3c_irqsub_mask(irqno, INTMSK_CFSDI, SUBMSK_CFSDI);
+}
+
+static void s3c2412_irq_cfsdi_unmask(unsigned int irqno)
+{
+	s3c_irqsub_unmask(irqno, INTMSK_CFSDI);
+}
+
+static void s3c2412_irq_cfsdi_ack(unsigned int irqno)
+{
+	s3c_irqsub_maskack(irqno, INTMSK_CFSDI, SUBMSK_CFSDI);
+}
+
+static struct irq_chip s3c2412_irq_cfsdi = {
+	.name		= "s3c2412-cfsdi",
+	.ack		= s3c2412_irq_cfsdi_ack,
+	.mask		= s3c2412_irq_cfsdi_mask,
+	.unmask		= s3c2412_irq_cfsdi_unmask,
+};
+
 static int s3c2412_irq_add(struct sys_device *sysdev)
 {
 	unsigned int irqno;
@@ -115,6 +163,16 @@
 		set_irq_flags(irqno, IRQF_VALID);
 	}
 
+	/* add demux support for CF/SDI */
+
+	set_irq_chained_handler(IRQ_S3C2412_CFSDI, s3c2412_irq_demux_cfsdi);
+
+	for (irqno = IRQ_S3C2412_SDI; irqno <= IRQ_S3C2412_CF; irqno++) {
+		set_irq_chip(irqno, &s3c2412_irq_cfsdi);
+		set_irq_handler(irqno, handle_level_irq);
+		set_irq_flags(irqno, IRQF_VALID);
+	}
+
 	return 0;
 }