Merge tag 'irq-s3c24xx-for-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into next/drivers

From Kukjin Kim <kgene.kim@samsung.com>:

s3c24xx irq cleanup and move into drivers/irqchip

* tag 'irq-s3c24xx-for-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  irqchip: s3c24xx: add devicetree support
  irqchip: s3c24xx: make interrupt handling independent of irq_domain structure
  irqchip: s3c24xx: globally keep track of the created intc instances
  irqchip: s3c24xx: add irq_set_type callback for basic interrupt types
  irqchip: s3c24xx: fix irqlist of second s3c2416 controller
  irqchip: s3c24xx: fix comments on some camera interrupts
  ARM: S3C24XX: move irq driver to drivers/irqchip
  ARM: S3C24XX: add handle_irq function
  ARM: S3C24XX: make s3c24xx_init_intc static
  ARM: S3C24XX: move s3c24xx_init_irq to s3c2410_init_irq
  ARM: S3C24XX: fix irq parent check
  ARM: S3C24XX: fix redundant checks in the irq mapping function

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

17 files changed, 472 insertions, 205 deletions

diff --git a/Documentation/devicetree/bindings/interrupt-controller/samsung,s3c24xx-irq.txt b/Documentation/devicetree/bindings/interrupt-controller/samsung,s3c24xx-irq.txt
new file mode 100644
index 00000000000..c54c5a9a2a9
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/samsung,s3c24xx-irq.txt
@@ -0,0 +1,53 @@
+Samsung S3C24XX Interrupt Controllers
+
+The S3C24XX SoCs contain a custom set of interrupt controllers providing a
+varying number of interrupt sources. The set consists of a main- and sub-
+controller and on newer SoCs even a second main controller.
+
+Required properties:
+- compatible: Compatible property value should be "samsung,s3c2410-irq"
+  for machines before s3c2416 and "samsung,s3c2416-irq" for s3c2416 and later.
+
+- reg: Physical base address of the controller and length of memory mapped
+  region.
+
+- interrupt-controller : Identifies the node as an interrupt controller
+
+- #interrupt-cells : Specifies the number of cells needed to encode an
+  interrupt source. The value shall be 4 and interrupt descriptor shall
+  have the following format:
+      <ctrl_num parent_irq ctrl_irq type>
+
+  ctrl_num contains the controller to use:
+      - 0 ... main controller
+      - 1 ... sub controller
+      - 2 ... second main controller on s3c2416 and s3c2450
+  parent_irq contains the parent bit in the main controller and will be
+             ignored in main controllers
+  ctrl_irq contains the interrupt bit of the controller
+  type contains the trigger type to use
+
+Example:
+
+	interrupt-controller@4a000000 {
+		compatible = "samsung,s3c2410-irq";
+		reg = <0x4a000000 0x100>;
+		interrupt-controller;
+		#interrupt-cells=<4>;
+	};
+
+	[...]
+
+	serial@50000000 {
+		compatible = "samsung,s3c2410-uart";
+		reg = <0x50000000 0x4000>;
+		interrupt-parent = <&subintc>;
+		interrupts = <1 28 0 4>, <1 28 1 4>;
+	};
+
+	rtc@57000000 {
+		compatible = "samsung,s3c2410-rtc";
+		reg = <0x57000000 0x100>;
+		interrupt-parent = <&intc>;
+		interrupts = <0 30 0 3>, <0 8 0 3>;
+	};
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index ada582b15cf..6adf79869f8 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -778,6 +778,7 @@ config ARCH_S3C24XX
 	select HAVE_S3C2410_I2C if I2C
 	select HAVE_S3C2410_WATCHDOG if WATCHDOG
 	select HAVE_S3C_RTC if RTC_CLASS
+	select MULTI_IRQ_HANDLER
 	select NEED_MACH_GPIO_H
 	select NEED_MACH_IO_H
 	help
diff --git a/arch/arm/mach-s3c24xx/Makefile b/arch/arm/mach-s3c24xx/Makefile
index be6e4d0e6f1..6f46ecfc839 100644
--- a/arch/arm/mach-s3c24xx/Makefile
+++ b/arch/arm/mach-s3c24xx/Makefile
@@ -14,7 +14,7 @@ obj-				:=
 
 # core
 
-obj-y				+= common.o irq.o
+obj-y				+= common.o
 
 obj-$(CONFIG_CPU_S3C2410)	+= s3c2410.o
 obj-$(CONFIG_S3C2410_CPUFREQ)	+= cpufreq-s3c2410.o
diff --git a/arch/arm/mach-s3c24xx/common.h b/arch/arm/mach-s3c24xx/common.h
index abefeb38bba..307c3714be5 100644
--- a/arch/arm/mach-s3c24xx/common.h
+++ b/arch/arm/mach-s3c24xx/common.h
@@ -21,6 +21,7 @@ extern void s3c2410_map_io(void);
 extern void s3c2410_init_uarts(struct s3c2410_uartcfg *cfg, int no);
 extern void s3c2410_init_clocks(int xtal);
 extern void s3c2410_restart(char mode, const char *cmd);
+extern void s3c2410_init_irq(void);
 #else
 #define s3c2410_init_clocks NULL
 #define s3c2410_init_uarts NULL
diff --git a/arch/arm/mach-s3c24xx/include/mach/entry-macro.S b/arch/arm/mach-s3c24xx/include/mach/entry-macro.S
deleted file mode 100644
index 6a21beeba1d..00000000000
--- a/arch/arm/mach-s3c24xx/include/mach/entry-macro.S
+++ /dev/null
@@ -1,70 +0,0 @@
-/*
- * arch/arm/mach-s3c2410/include/mach/entry-macro.S
- *
- * Low-level IRQ helper macros for S3C2410-based platforms
- *
- * This file is licensed under  the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
-*/
-
-/* We have a problem that the INTOFFSET register does not always
- * show one interrupt. Occasionally we get two interrupts through
- * the prioritiser, and this causes the INTOFFSET register to show
- * what looks like the logical-or of the two interrupt numbers.
- *
- * Thanks to Klaus, Shannon, et al for helping to debug this problem
-*/
-
-#define INTPND		(0x10)
-#define INTOFFSET	(0x14)
-
-#include <mach/hardware.h>
-#include <asm/irq.h>
-
-	.macro  get_irqnr_preamble, base, tmp
-	.endm
-
-	.macro	get_irqnr_and_base, irqnr, irqstat, base, tmp
-
-		mov	\base, #S3C24XX_VA_IRQ
-
-		@@ try the interrupt offset register, since it is there
-
-		ldr	\irqstat, [\base, #INTPND ]
-		teq	\irqstat, #0
-		beq	1002f
-		ldr	\irqnr, [\base, #INTOFFSET ]
-		mov	\tmp, #1
-		tst	\irqstat, \tmp, lsl \irqnr
-		bne	1001f
-
-		@@ the number specified is not a valid irq, so try
-		@@ and work it out for ourselves
-
-		mov	\irqnr, #0		@@ start here
-
-		@@ work out which irq (if any) we got
-
-		movs	\tmp, \irqstat, lsl#16
-		addeq	\irqnr, \irqnr, #16
-		moveq	\irqstat, \irqstat, lsr#16
-		tst	\irqstat, #0xff
-		addeq	\irqnr, \irqnr, #8
-		moveq	\irqstat, \irqstat, lsr#8
-		tst	\irqstat, #0xf
-		addeq	\irqnr, \irqnr, #4
-		moveq	\irqstat, \irqstat, lsr#4
-		tst	\irqstat, #0x3
-		addeq	\irqnr, \irqnr, #2
-		moveq	\irqstat, \irqstat, lsr#2
-		tst	\irqstat, #0x1
-		addeq	\irqnr, \irqnr, #1
-
-		@@ we have the value
-1001:
-		adds	\irqnr, \irqnr, #IRQ_EINT0
-1002:
-		@@ exit here, Z flag unset if IRQ
-
-	.endm
diff --git a/arch/arm/mach-s3c24xx/mach-amlm5900.c b/arch/arm/mach-s3c24xx/mach-amlm5900.c
index 432144cb54a..e27b5c91b3d 100644
--- a/arch/arm/mach-s3c24xx/mach-amlm5900.c
+++ b/arch/arm/mach-s3c24xx/mach-amlm5900.c
@@ -238,7 +238,7 @@ static void __init amlm5900_init(void)
 MACHINE_START(AML_M5900, "AML_M5900")
 	.atag_offset	= 0x100,
 	.map_io		= amlm5900_map_io,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_machine	= amlm5900_init,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
diff --git a/arch/arm/mach-s3c24xx/mach-bast.c b/arch/arm/mach-s3c24xx/mach-bast.c
index eabe2db42ef..22d6ae926d9 100644
--- a/arch/arm/mach-s3c24xx/mach-bast.c
+++ b/arch/arm/mach-s3c24xx/mach-bast.c
@@ -605,7 +605,7 @@ MACHINE_START(BAST, "Simtec-BAST")
 	/* Maintainer: Ben Dooks <ben@simtec.co.uk> */
 	.atag_offset	= 0x100,
 	.map_io		= bast_map_io,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_machine	= bast_init,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
diff --git a/arch/arm/mach-s3c24xx/mach-h1940.c b/arch/arm/mach-s3c24xx/mach-h1940.c
index 8dd66010284..af4334d6b4d 100644
--- a/arch/arm/mach-s3c24xx/mach-h1940.c
+++ b/arch/arm/mach-s3c24xx/mach-h1940.c
@@ -667,11 +667,6 @@ static void __init h1940_reserve(void)
 	memblock_reserve(0x30081000, 0x1000);
 }
 
-static void __init h1940_init_irq(void)
-{
-	s3c24xx_init_irq();
-}
-
 static void __init h1940_init(void)
 {
 	u32 tmp;
@@ -740,7 +735,7 @@ MACHINE_START(H1940, "IPAQ-H1940")
 	.atag_offset	= 0x100,
 	.map_io		= h1940_map_io,
 	.reserve	= h1940_reserve,
-	.init_irq	= h1940_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_machine	= h1940_init,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
diff --git a/arch/arm/mach-s3c24xx/mach-n30.c b/arch/arm/mach-s3c24xx/mach-n30.c
index 73a690f431e..2cb46c37c92 100644
--- a/arch/arm/mach-s3c24xx/mach-n30.c
+++ b/arch/arm/mach-s3c24xx/mach-n30.c
@@ -592,7 +592,7 @@ MACHINE_START(N30, "Acer-N30")
 	.atag_offset	= 0x100,
 	.init_time	= samsung_timer_init,
 	.init_machine	= n30_init,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.map_io		= n30_map_io,
 	.restart	= s3c2410_restart,
 MACHINE_END
@@ -603,7 +603,7 @@ MACHINE_START(N35, "Acer-N35")
 	.atag_offset	= 0x100,
 	.init_time	= samsung_timer_init,
 	.init_machine	= n30_init,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.map_io		= n30_map_io,
 	.restart	= s3c2410_restart,
 MACHINE_END
diff --git a/arch/arm/mach-s3c24xx/mach-otom.c b/arch/arm/mach-s3c24xx/mach-otom.c
index 7b8670746b6..7e16b0740ec 100644
--- a/arch/arm/mach-s3c24xx/mach-otom.c
+++ b/arch/arm/mach-s3c24xx/mach-otom.c
@@ -116,7 +116,7 @@ MACHINE_START(OTOM, "Nex Vision - Otom 1.1")
 	.atag_offset	= 0x100,
 	.map_io		= otom11_map_io,
 	.init_machine	= otom11_init,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
 MACHINE_END
diff --git a/arch/arm/mach-s3c24xx/mach-qt2410.c b/arch/arm/mach-s3c24xx/mach-qt2410.c
index 71cf29b12d1..f8feaeadb55 100644
--- a/arch/arm/mach-s3c24xx/mach-qt2410.c
+++ b/arch/arm/mach-s3c24xx/mach-qt2410.c
@@ -343,7 +343,7 @@ static void __init qt2410_machine_init(void)
 MACHINE_START(QT2410, "QT2410")
 	.atag_offset	= 0x100,
 	.map_io		= qt2410_map_io,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_machine	= qt2410_machine_init,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
diff --git a/arch/arm/mach-s3c24xx/mach-smdk2410.c b/arch/arm/mach-s3c24xx/mach-smdk2410.c
index fd96f7fc330..a773789e4f3 100644
--- a/arch/arm/mach-s3c24xx/mach-smdk2410.c
+++ b/arch/arm/mach-s3c24xx/mach-smdk2410.c
@@ -116,7 +116,7 @@ MACHINE_START(SMDK2410, "SMDK2410") /* @TODO: request a new identifier and switc
 	/* Maintainer: Jonas Dietsche */
 	.atag_offset	= 0x100,
 	.map_io		= smdk2410_map_io,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_machine	= smdk2410_init,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
diff --git a/arch/arm/mach-s3c24xx/mach-tct_hammer.c b/arch/arm/mach-s3c24xx/mach-tct_hammer.c
index 31dfe589e34..7fad8f055ca 100644
--- a/arch/arm/mach-s3c24xx/mach-tct_hammer.c
+++ b/arch/arm/mach-s3c24xx/mach-tct_hammer.c
@@ -149,7 +149,7 @@ static void __init tct_hammer_init(void)
 MACHINE_START(TCT_HAMMER, "TCT_HAMMER")
 	.atag_offset	= 0x100,
 	.map_io		= tct_hammer_map_io,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_machine	= tct_hammer_init,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
diff --git a/arch/arm/mach-s3c24xx/mach-vr1000.c b/arch/arm/mach-s3c24xx/mach-vr1000.c
index deeb8a0a403..42e7187fed6 100644
--- a/arch/arm/mach-s3c24xx/mach-vr1000.c
+++ b/arch/arm/mach-s3c24xx/mach-vr1000.c
@@ -355,7 +355,7 @@ MACHINE_START(VR1000, "Thorcom-VR1000")
 	.atag_offset	= 0x100,
 	.map_io		= vr1000_map_io,
 	.init_machine	= vr1000_init,
-	.init_irq	= s3c24xx_init_irq,
+	.init_irq	= s3c2410_init_irq,
 	.init_time	= samsung_timer_init,
 	.restart	= s3c2410_restart,
 MACHINE_END
diff --git a/arch/arm/plat-samsung/include/plat/cpu.h b/arch/arm/plat-samsung/include/plat/cpu.h
index 0f6c47a6475..989fefe18be 100644
--- a/arch/arm/plat-samsung/include/plat/cpu.h
+++ b/arch/arm/plat-samsung/include/plat/cpu.h
@@ -183,7 +183,6 @@ extern void s3c_init_cpu(unsigned long idcode,
 
 /* core initialisation functions */
 
-extern void s3c24xx_init_irq(void);
 extern void s5p_init_irq(u32 *vic, u32 num_vic);
 
 extern void s3c24xx_init_io(struct map_desc *mach_desc, int size);
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index e41ceb9bec2..acf98953272 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_IRQCHIP)			+= irqchip.o
 
 obj-$(CONFIG_ARCH_BCM2835)		+= irq-bcm2835.o
 obj-$(CONFIG_ARCH_EXYNOS)		+= exynos-combiner.o
+obj-$(CONFIG_ARCH_S3C24XX)		+= irq-s3c24xx.o
 obj-$(CONFIG_METAG)			+= irq-metag-ext.o
 obj-$(CONFIG_METAG_PERFCOUNTER_IRQS)	+= irq-metag.o
 obj-$(CONFIG_ARCH_SUNXI)		+= irq-sunxi.o
diff --git a/arch/arm/mach-s3c24xx/irq.c b/drivers/irqchip/irq-s3c24xx.c
index 3f3de749209..5e40b3424df 100644
--- a/arch/arm/mach-s3c24xx/irq.c
+++ b/drivers/irqchip/irq-s3c24xx.c
@@ -25,7 +25,11 @@
 #include <linux/ioport.h>
 #include <linux/device.h>
 #include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
 
+#include <asm/exception.h>
 #include <asm/mach/irq.h>
 
 #include <mach/regs-irq.h>
@@ -35,6 +39,8 @@
 #include <plat/regs-irqtype.h>
 #include <plat/pm.h>
 
+#include "irqchip.h"
+
 #define S3C_IRQTYPE_NONE	0
 #define S3C_IRQTYPE_EINT	1
 #define S3C_IRQTYPE_EDGE	2
@@ -42,6 +48,7 @@
 
 struct s3c_irq_data {
 	unsigned int type;
+	unsigned long offset;
 	unsigned long parent_irq;
 
 	/* data gets filled during init */
@@ -68,23 +75,34 @@ struct s3c_irq_intc {
 	struct s3c_irq_data	*irqs;
 };
 
+/*
+ * Array holding pointers to the global controller structs
+ * [0] ... main_intc
+ * [1] ... sub_intc
+ * [2] ... main_intc2 on s3c2416
+ */
+static struct s3c_irq_intc *s3c_intc[3];
+
 static void s3c_irq_mask(struct irq_data *data)
 {
-	struct s3c_irq_intc *intc = data->domain->host_data;
+	struct s3c_irq_data *irq_data = irq_data_get_irq_chip_data(data);
+	struct s3c_irq_intc *intc = irq_data->intc;
 	struct s3c_irq_intc *parent_intc = intc->parent;
-	struct s3c_irq_data *irq_data = &intc->irqs[data->hwirq];
 	struct s3c_irq_data *parent_data;
 	unsigned long mask;
 	unsigned int irqno;
 
 	mask = __raw_readl(intc->reg_mask);
-	mask |= (1UL << data->hwirq);
+	mask |= (1UL << irq_data->offset);
 	__raw_writel(mask, intc->reg_mask);
 
-	if (parent_intc && irq_data->parent_irq) {
+	if (parent_intc) {
 		parent_data = &parent_intc->irqs[irq_data->parent_irq];
 
-		/* check to see if we need to mask the parent IRQ */
+		/* check to see if we need to mask the parent IRQ
+		 * The parent_irq is always in main_intc, so the hwirq
+		 * for find_mapping does not need an offset in any case.
+		 */
 		if ((mask & parent_data->sub_bits) == parent_data->sub_bits) {
 			irqno = irq_find_mapping(parent_intc->domain,
 					 irq_data->parent_irq);
@@ -95,17 +113,17 @@ static void s3c_irq_mask(struct irq_data *data)
 
 static void s3c_irq_unmask(struct irq_data *data)
 {
-	struct s3c_irq_intc *intc = data->domain->host_data;
+	struct s3c_irq_data *irq_data = irq_data_get_irq_chip_data(data);
+	struct s3c_irq_intc *intc = irq_data->intc;
 	struct s3c_irq_intc *parent_intc = intc->parent;
-	struct s3c_irq_data *irq_data = &intc->irqs[data->hwirq];
 	unsigned long mask;
 	unsigned int irqno;
 
 	mask = __raw_readl(intc->reg_mask);
-	mask &= ~(1UL << data->hwirq);
+	mask &= ~(1UL << irq_data->offset);
 	__raw_writel(mask, intc->reg_mask);
 
-	if (parent_intc && irq_data->parent_irq) {
+	if (parent_intc) {
 		irqno = irq_find_mapping(parent_intc->domain,
 					 irq_data->parent_irq);
 		s3c_irq_unmask(irq_get_irq_data(irqno));
@@ -114,14 +132,37 @@ static void s3c_irq_unmask(struct irq_data *data)
 
 static inline void s3c_irq_ack(struct irq_data *data)
 {
-	struct s3c_irq_intc *intc = data->domain->host_data;
-	unsigned long bitval = 1UL << data->hwirq;
+	struct s3c_irq_data *irq_data = irq_data_get_irq_chip_data(data);
+	struct s3c_irq_intc *intc = irq_data->intc;
+	unsigned long bitval = 1UL << irq_data->offset;
 
 	__raw_writel(bitval, intc->reg_pending);
 	if (intc->reg_intpnd)
 		__raw_writel(bitval, intc->reg_intpnd);
 }
 
+static int s3c_irq_type(struct irq_data *data, unsigned int type)
+{
+	switch (type) {
+	case IRQ_TYPE_NONE:
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+	case IRQ_TYPE_EDGE_FALLING:
+	case IRQ_TYPE_EDGE_BOTH:
+		irq_set_handler(data->irq, handle_edge_irq);
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+	case IRQ_TYPE_LEVEL_HIGH:
+		irq_set_handler(data->irq, handle_level_irq);
+		break;
+	default:
+		pr_err("No such irq type %d", type);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int s3c_irqext_type_set(void __iomem *gpcon_reg,
 			       void __iomem *extint_reg,
 			       unsigned long gpcon_offset,
@@ -227,6 +268,7 @@ static struct irq_chip s3c_irq_chip = {
 	.irq_ack	= s3c_irq_ack,
 	.irq_mask	= s3c_irq_mask,
 	.irq_unmask	= s3c_irq_unmask,
+	.irq_set_type	= s3c_irq_type,
 	.irq_set_wake	= s3c_irq_wake
 };
 
@@ -235,6 +277,7 @@ static struct irq_chip s3c_irq_level_chip = {
 	.irq_mask	= s3c_irq_mask,
 	.irq_unmask	= s3c_irq_unmask,
 	.irq_ack	= s3c_irq_ack,
+	.irq_set_type	= s3c_irq_type,
 };
 
 static struct irq_chip s3c_irqext_chip = {
@@ -258,12 +301,19 @@ static struct irq_chip s3c_irq_eint0t4 = {
 static void s3c_irq_demux(unsigned int irq, struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-	struct s3c_irq_intc *intc = desc->irq_data.domain->host_data;
-	struct s3c_irq_data *irq_data = &intc->irqs[desc->irq_data.hwirq];
+	struct s3c_irq_data *irq_data = irq_desc_get_chip_data(desc);
+	struct s3c_irq_intc *intc = irq_data->intc;
 	struct s3c_irq_intc *sub_intc = irq_data->sub_intc;
 	unsigned long src;
 	unsigned long msk;
 	unsigned int n;
+	unsigned int offset;
+
+	/* we're using individual domains for the non-dt case
+	 * and one big domain for the dt case where the subintc
+	 * starts at hwirq number 32.
+	 */
+	offset = (intc->domain->of_node) ? 32 : 0;
 
 	chained_irq_enter(chip, desc);
 
@@ -276,12 +326,64 @@ static void s3c_irq_demux(unsigned int irq, struct irq_desc *desc)
 	while (src) {
 		n = __ffs(src);
 		src &= ~(1 << n);
-		generic_handle_irq(irq_find_mapping(sub_intc->domain, n));
+		irq = irq_find_mapping(sub_intc->domain, offset + n);
+		generic_handle_irq(irq);
 	}
 
 	chained_irq_exit(chip, desc);
 }
 
+static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc,
+				      struct pt_regs *regs, int intc_offset)
+{
+	int pnd;
+	int offset;
+	int irq;
+
+	pnd = __raw_readl(intc->reg_intpnd);
+	if (!pnd)
+		return false;
+
+	/* non-dt machines use individual domains */
+	if (!intc->domain->of_node)
+		intc_offset = 0;
+
+	/* We have a problem that the INTOFFSET register does not always
+	 * show one interrupt. Occasionally we get two interrupts through
+	 * the prioritiser, and this causes the INTOFFSET register to show
+	 * what looks like the logical-or of the two interrupt numbers.
+	 *
+	 * Thanks to Klaus, Shannon, et al for helping to debug this problem
+	 */
+	offset = __raw_readl(intc->reg_intpnd + 4);
+
+	/* Find the bit manually, when the offset is wrong.
+	 * The pending register only ever contains the one bit of the next
+	 * interrupt to handle.
+	 */
+	if (!(pnd & (1 << offset)))
+		offset =  __ffs(pnd);
+
+	irq = irq_find_mapping(intc->domain, intc_offset + offset);
+	handle_IRQ(irq, regs);
+	return true;
+}
+
+asmlinkage void __exception_irq_entry s3c24xx_handle_irq(struct pt_regs *regs)
+{
+	do {
+		if (likely(s3c_intc[0]))
+			if (s3c24xx_handle_intc(s3c_intc[0], regs, 0))
+				continue;
+
+		if (s3c_intc[2])
+			if (s3c24xx_handle_intc(s3c_intc[2], regs, 64))
+				continue;
+
+		break;
+	} while (1);
+}
+
 #ifdef CONFIG_FIQ
 /**
  * s3c24xx_set_fiq - set the FIQ routing
@@ -324,18 +426,11 @@ static int s3c24xx_irq_map(struct irq_domain *h, unsigned int virq,
 	struct s3c_irq_data *parent_irq_data;
 	unsigned int irqno;
 
-	if (!intc) {
-		pr_err("irq-s3c24xx: no controller found for hwirq %lu\n", hw);
-		return -EINVAL;
-	}
-
-	if (!irq_data) {
-		pr_err("irq-s3c24xx: no irq data found for hwirq %lu\n", hw);
-		return -EINVAL;
-	}
-
 	/* attach controller pointer to irq_data */
 	irq_data->intc = intc;
+	irq_data->offset = hw;
+
+	parent_intc = intc->parent;
 
 	/* set handler and flags */
 	switch (irq_data->type) {
@@ -345,7 +440,7 @@ static int s3c24xx_irq_map(struct irq_domain *h, unsigned int virq,
 		/* On the S3C2412, the EINT0to3 have a parent irq
 		 * but need the s3c_irq_eint0t4 chip
 		 */
-		if (irq_data->parent_irq && (!soc_is_s3c2412() || hw >= 4))
+		if (parent_intc && (!soc_is_s3c2412() || hw >= 4))
 			irq_set_chip_and_handler(virq, &s3c_irqext_chip,
 						 handle_edge_irq);
 		else
@@ -353,8 +448,7 @@ static int s3c24xx_irq_map(struct irq_domain *h, unsigned int virq,
 						 handle_edge_irq);
 		break;
 	case S3C_IRQTYPE_EDGE:
-		if (irq_data->parent_irq ||
-		    intc->reg_pending == S3C2416_SRCPND2)
+		if (parent_intc || intc->reg_pending == S3C2416_SRCPND2)
 			irq_set_chip_and_handler(virq, &s3c_irq_level_chip,
 						 handle_edge_irq);
 		else
@@ -362,7 +456,7 @@ static int s3c24xx_irq_map(struct irq_domain *h, unsigned int virq,
 						 handle_edge_irq);
 		break;
 	case S3C_IRQTYPE_LEVEL:
-		if (irq_data->parent_irq)
+		if (parent_intc)
 			irq_set_chip_and_handler(virq, &s3c_irq_level_chip,
 						 handle_level_irq);
 		else
@@ -373,23 +467,19 @@ static int s3c24xx_irq_map(struct irq_domain *h, unsigned int virq,
 		pr_err("irq-s3c24xx: unsupported irqtype %d\n", irq_data->type);
 		return -EINVAL;
 	}
+
+	irq_set_chip_data(virq, irq_data);
+
 	set_irq_flags(virq, IRQF_VALID);
 
-	if (irq_data->parent_irq) {
-		parent_intc = intc->parent;
-		if (!parent_intc) {
-			pr_err("irq-s3c24xx: no parent controller found for hwirq %lu\n",
-			       hw);
+	if (parent_intc && irq_data->type != S3C_IRQTYPE_NONE) {
+		if (irq_data->parent_irq > 31) {
+			pr_err("irq-s3c24xx: parent irq %lu is out of range\n",
+			       irq_data->parent_irq);
 			goto err;
 		}
 
 		parent_irq_data = &parent_intc->irqs[irq_data->parent_irq];
-		if (!irq_data) {
-			pr_err("irq-s3c24xx: no irq data found for hwirq %lu\n",
-			       hw);
-			goto err;
-		}
-
 		parent_irq_data->sub_intc = intc;
 		parent_irq_data->sub_bits |= (1UL << hw);
 
@@ -444,7 +534,7 @@ static void s3c24xx_clear_intc(struct s3c_irq_intc *intc)
 	}
 }
 
-struct s3c_irq_intc *s3c24xx_init_intc(struct device_node *np,
+static struct s3c_irq_intc *s3c24xx_init_intc(struct device_node *np,
 				       struct s3c_irq_data *irq_data,
 				       struct s3c_irq_intc *parent,
 				       unsigned long address)
@@ -518,6 +608,8 @@ struct s3c_irq_intc *s3c24xx_init_intc(struct device_node *np,
 		goto err;
 	}
 
+	set_handle_irq(s3c24xx_handle_irq);
+
 	return intc;
 
 err:
@@ -525,12 +617,35 @@ err:
 	return ERR_PTR(ret);
 }
 
-/* s3c24xx_init_irq
- *
- * Initialise S3C2410 IRQ system
-*/
+static struct s3c_irq_data init_eint[32] = {
+	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
+	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
+	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
+	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT4 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT5 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT6 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT7 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT8 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT9 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT10 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT11 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT12 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT13 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT14 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT15 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT16 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT17 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT18 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT19 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT20 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT21 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT22 */
+	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT23 */
+};
 
-static struct s3c_irq_data init_base[32] = {
+#ifdef CONFIG_CPU_S3C2410
+static struct s3c_irq_data init_s3c2410base[32] = {
 	{ .type = S3C_IRQTYPE_EINT, }, /* EINT0 */
 	{ .type = S3C_IRQTYPE_EINT, }, /* EINT1 */
 	{ .type = S3C_IRQTYPE_EINT, }, /* EINT2 */
@@ -565,34 +680,7 @@ static struct s3c_irq_data init_base[32] = {
 	{ .type = S3C_IRQTYPE_LEVEL, }, /* ADCPARENT */
 };
 
-static struct s3c_irq_data init_eint[32] = {
-	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
-	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
-	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
-	{ .type = S3C_IRQTYPE_NONE, }, /* reserved */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT4 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT5 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT6 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 4 }, /* EINT7 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT8 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT9 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT10 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT11 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT12 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT13 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT14 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT15 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT16 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT17 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT18 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT19 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT20 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT21 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT22 */
-	{ .type = S3C_IRQTYPE_EINT, .parent_irq = 5 }, /* EINT23 */
-};
-
-static struct s3c_irq_data init_subint[32] = {
+static struct s3c_irq_data init_s3c2410subint[32] = {
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 28 }, /* UART0-RX */
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 28 }, /* UART0-TX */
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 28 }, /* UART0-ERR */
@@ -606,23 +694,24 @@ static struct s3c_irq_data init_subint[32] = {
 	{ .type = S3C_IRQTYPE_EDGE, .parent_irq = 31 }, /* ADC */
 };
 
-void __init s3c24xx_init_irq(void)
+void __init s3c2410_init_irq(void)
 {
-	struct s3c_irq_intc *main_intc;
-
 #ifdef CONFIG_FIQ
 	init_FIQ(FIQ_START);
 #endif
 
-	main_intc = s3c24xx_init_intc(NULL, &init_base[0], NULL, 0x4a000000);
-	if (IS_ERR(main_intc)) {
+	s3c_intc[0] = s3c24xx_init_intc(NULL, &init_s3c2410base[0], NULL,
+					0x4a000000);
+	if (IS_ERR(s3c_intc[0])) {
 		pr_err("irq: could not create main interrupt controller\n");
 		return;
 	}
 
-	s3c24xx_init_intc(NULL, &init_subint[0], main_intc, 0x4a000018);
-	s3c24xx_init_intc(NULL, &init_eint[0], main_intc, 0x560000a4);
+	s3c_intc[1] = s3c24xx_init_intc(NULL, &init_s3c2410subint[0],
+					s3c_intc[0], 0x4a000018);
+	s3c24xx_init_intc(NULL, &init_eint[0], s3c_intc[0], 0x560000a4);
 }
+#endif
 
 #ifdef CONFIG_CPU_S3C2412
 static struct s3c_irq_data init_s3c2412base[32] = {
@@ -707,22 +796,22 @@ static struct s3c_irq_data init_s3c2412subint[32] = {
 
 void s3c2412_init_irq(void)
 {
-	struct s3c_irq_intc *main_intc;
-
 	pr_info("S3C2412: IRQ Support\n");
 
 #ifdef CONFIG_FIQ
 	init_FIQ(FIQ_START);
 #endif
 
-	main_intc = s3c24xx_init_intc(NULL, &init_s3c2412base[0], NULL, 0x4a000000);
-	if (IS_ERR(main_intc)) {
+	s3c_intc[0] = s3c24xx_init_intc(NULL, &init_s3c2412base[0], NULL,
+					0x4a000000);
+	if (IS_ERR(s3c_intc[0])) {
 		pr_err("irq: could not create main interrupt controller\n");
 		return;
 	}
 
-	s3c24xx_init_intc(NULL, &init_s3c2412eint[0], main_intc, 0x560000a4);
-	s3c24xx_init_intc(NULL, &init_s3c2412subint[0], main_intc, 0x4a000018);
+	s3c24xx_init_intc(NULL, &init_s3c2412eint[0], s3c_intc[0], 0x560000a4);
+	s3c_intc[1] = s3c24xx_init_intc(NULL, &init_s3c2412subint[0],
+					s3c_intc[0], 0x4a000018);
 }
 #endif
 
@@ -796,35 +885,35 @@ static struct s3c_irq_data init_s3c2416subint[32] = {
 
 static struct s3c_irq_data init_s3c2416_second[32] = {
 	{ .type = S3C_IRQTYPE_EDGE }, /* 2D */
-	{ .type = S3C_IRQTYPE_EDGE }, /* IIC1 */
+	{ .type = S3C_IRQTYPE_NONE }, /* reserved */
 	{ .type = S3C_IRQTYPE_NONE }, /* reserved */
 	{ .type = S3C_IRQTYPE_NONE }, /* reserved */
 	{ .type = S3C_IRQTYPE_EDGE }, /* PCM0 */
-	{ .type = S3C_IRQTYPE_EDGE }, /* PCM1 */
+	{ .type = S3C_IRQTYPE_NONE }, /* reserved */
 	{ .type = S3C_IRQTYPE_EDGE }, /* I2S0 */
-	{ .type = S3C_IRQTYPE_EDGE }, /* I2S1 */
 };
 
 void __init s3c2416_init_irq(void)
 {
-	struct s3c_irq_intc *main_intc;
-
 	pr_info("S3C2416: IRQ Support\n");
 
 #ifdef CONFIG_FIQ
 	init_FIQ(FIQ_START);
 #endif
 
-	main_intc = s3c24xx_init_intc(NULL, &init_s3c2416base[0], NULL, 0x4a000000);
-	if (IS_ERR(main_intc)) {
+	s3c_intc[0] = s3c24xx_init_intc(NULL, &init_s3c2416base[0], NULL,
+					0x4a000000);
+	if (IS_ERR(s3c_intc[0])) {
 		pr_err("irq: could not create main interrupt controller\n");
 		return;
 	}
 
-	s3c24xx_init_intc(NULL, &init_eint[0], main_intc, 0x560000a4);
-	s3c24xx_init_intc(NULL, &init_s3c2416subint[0], main_intc, 0x4a000018);
+	s3c24xx_init_intc(NULL, &init_eint[0], s3c_intc[0], 0x560000a4);
+	s3c_intc[1] = s3c24xx_init_intc(NULL, &init_s3c2416subint[0],
+					s3c_intc[0], 0x4a000018);
 
-	s3c24xx_init_intc(NULL, &init_s3c2416_second[0], NULL, 0x4a000040);
+	s3c_intc[2] = s3c24xx_init_intc(NULL, &init_s3c2416_second[0],
+					NULL, 0x4a000040);
 }
 
 #endif
@@ -877,30 +966,30 @@ static struct s3c_irq_data init_s3c2440subint[32] = {
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 15 }, /* UART2-ERR */
 	{ .type = S3C_IRQTYPE_EDGE, .parent_irq = 31 }, /* TC */
 	{ .type = S3C_IRQTYPE_EDGE, .parent_irq = 31 }, /* ADC */
-	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* TC */
-	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* ADC */
+	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* CAM_C */
+	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* CAM_P */
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 9 }, /* WDT */
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 9 }, /* AC97 */
 };
 
 void __init s3c2440_init_irq(void)
 {
-	struct s3c_irq_intc *main_intc;
-
 	pr_info("S3C2440: IRQ Support\n");
 
 #ifdef CONFIG_FIQ
 	init_FIQ(FIQ_START);
 #endif
 
-	main_intc = s3c24xx_init_intc(NULL, &init_s3c2440base[0], NULL, 0x4a000000);
-	if (IS_ERR(main_intc)) {
+	s3c_intc[0] = s3c24xx_init_intc(NULL, &init_s3c2440base[0], NULL,
+					0x4a000000);
+	if (IS_ERR(s3c_intc[0])) {
 		pr_err("irq: could not create main interrupt controller\n");
 		return;
 	}
 
-	s3c24xx_init_intc(NULL, &init_eint[0], main_intc, 0x560000a4);
-	s3c24xx_init_intc(NULL, &init_s3c2440subint[0], main_intc, 0x4a000018);
+	s3c24xx_init_intc(NULL, &init_eint[0], s3c_intc[0], 0x560000a4);
+	s3c_intc[1] = s3c24xx_init_intc(NULL, &init_s3c2440subint[0],
+					s3c_intc[0], 0x4a000018);
 }
 #endif
 
@@ -952,28 +1041,28 @@ static struct s3c_irq_data init_s3c2442subint[32] = {
 	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 15 }, /* UART2-ERR */
 	{ .type = S3C_IRQTYPE_EDGE, .parent_irq = 31 }, /* TC */
 	{ .type = S3C_IRQTYPE_EDGE, .parent_irq = 31 }, /* ADC */
-	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* TC */
-	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* ADC */
+	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* CAM_C */
+	{ .type = S3C_IRQTYPE_LEVEL, .parent_irq = 6 }, /* CAM_P */
 };
 
 void __init s3c2442_init_irq(void)
 {
-	struct s3c_irq_intc *main_intc;
-
 	pr_info("S3C2442: IRQ Support\n");
 
 #ifdef CONFIG_FIQ
 	init_FIQ(FIQ_START);
 #endif
 
-	main_intc = s3c24xx_init_intc(NULL, &init_s3c2442base[0], NULL, 0x4a000000);
-	if (IS_ERR(main_intc)) {
+	s3c_intc[0] = s3c24xx_init_intc(NULL, &init_s3c2442base[0], NULL,
+					0x4a000000);
+	if (IS_ERR(s3c_intc[0])) {
 		pr_err("irq: could not create main interrupt controller\n");
 		return;
 	}
 
-	s3c24xx_init_intc(NULL, &init_eint[0], main_intc, 0x560000a4);
-	s3c24xx_init_intc(NULL, &init_s3c2442subint[0], main_intc, 0x4a000018);
+	s3c24xx_init_intc(NULL, &init_eint[0], s3c_intc[0], 0x560000a4);
+	s3c_intc[1] = s3c24xx_init_intc(NULL, &init_s3c2442subint[0],
+					s3c_intc[0], 0x4a000018);
 }
 #endif
 
@@ -1048,21 +1137,219 @@ static struct s3c_irq_data init_s3c2443subint[32] = {
 
 void __init s3c2443_init_irq(void)
 {
-	struct s3c_irq_intc *main_intc;
-
 	pr_info("S3C2443: IRQ Support\n");
 
 #ifdef CONFIG_FIQ
 	init_FIQ(FIQ_START);
 #endif
 
-	main_intc = s3c24xx_init_intc(NULL, &init_s3c2443base[0], NULL, 0x4a000000);
-	if (IS_ERR(main_intc)) {
+	s3c_intc[0] = s3c24xx_init_intc(NULL, &init_s3c2443base[0], NULL,
+					0x4a000000);
+	if (IS_ERR(s3c_intc[0])) {
 		pr_err("irq: could not create main interrupt controller\n");
 		return;
 	}
 
-	s3c24xx_init_intc(NULL, &init_eint[0], main_intc, 0x560000a4);
-	s3c24xx_init_intc(NULL, &init_s3c2443subint[0], main_intc, 0x4a000018);
+	s3c24xx_init_intc(NULL, &init_eint[0], s3c_intc[0], 0x560000a4);
+	s3c_intc[1] = s3c24xx_init_intc(NULL, &init_s3c2443subint[0],
+					s3c_intc[0], 0x4a000018);
+}
+#endif
+
+#ifdef CONFIG_OF
+static int s3c24xx_irq_map_of(struct irq_domain *h, unsigned int virq,
+							irq_hw_number_t hw)
+{
+	unsigned int ctrl_num = hw / 32;
+	unsigned int intc_hw = hw % 32;
+	struct s3c_irq_intc *intc = s3c_intc[ctrl_num];
+	struct s3c_irq_intc *parent_intc = intc->parent;
+	struct s3c_irq_data *irq_data = &intc->irqs[intc_hw];
+
+	/* attach controller pointer to irq_data */
+	irq_data->intc = intc;
+	irq_data->offset = intc_hw;
+
+	if (!parent_intc)
+		irq_set_chip_and_handler(virq, &s3c_irq_chip, handle_edge_irq);
+	else
+		irq_set_chip_and_handler(virq, &s3c_irq_level_chip,
+					 handle_edge_irq);
+
+	irq_set_chip_data(virq, irq_data);
+
+	set_irq_flags(virq, IRQF_VALID);
+
+	return 0;
+}
+
+/* Translate our of irq notation
+ * format: <ctrl_num ctrl_irq parent_irq type>
+ */
+static int s3c24xx_irq_xlate_of(struct irq_domain *d, struct device_node *n,
+			const u32 *intspec, unsigned int intsize,
+			irq_hw_number_t *out_hwirq, unsigned int *out_type)
+{
+	struct s3c_irq_intc *intc;
+	struct s3c_irq_intc *parent_intc;
+	struct s3c_irq_data *irq_data;
+	struct s3c_irq_data *parent_irq_data;
+	int irqno;
+
+	if (WARN_ON(intsize < 4))
+		return -EINVAL;
+
+	if (intspec[0] > 2 || !s3c_intc[intspec[0]]) {
+		pr_err("controller number %d invalid\n", intspec[0]);
+		return -EINVAL;
+	}
+	intc = s3c_intc[intspec[0]];
+
+	*out_hwirq = intspec[0] * 32 + intspec[2];
+	*out_type = intspec[3] & IRQ_TYPE_SENSE_MASK;
+
+	parent_intc = intc->parent;
+	if (parent_intc) {
+		irq_data = &intc->irqs[intspec[2]];
+		irq_data->parent_irq = intspec[1];
+		parent_irq_data = &parent_intc->irqs[irq_data->parent_irq];
+		parent_irq_data->sub_intc = intc;
+		parent_irq_data->sub_bits |= (1UL << intspec[2]);
+
+		/* parent_intc is always s3c_intc[0], so no offset */
+		irqno = irq_create_mapping(parent_intc->domain, intspec[1]);
+		if (irqno < 0) {
+			pr_err("irq: could not map parent interrupt\n");
+			return irqno;
+		}
+
+		irq_set_chained_handler(irqno, s3c_irq_demux);
+	}
+
+	return 0;
+}
+
+static struct irq_domain_ops s3c24xx_irq_ops_of = {
+	.map = s3c24xx_irq_map_of,
+	.xlate = s3c24xx_irq_xlate_of,
+};
+
+struct s3c24xx_irq_of_ctrl {
+	char			*name;
+	unsigned long		offset;
+	struct s3c_irq_intc	**handle;
+	struct s3c_irq_intc	**parent;
+	struct irq_domain_ops	*ops;
+};
+
+static int __init s3c_init_intc_of(struct device_node *np,
+			struct device_node *interrupt_parent,
+			struct s3c24xx_irq_of_ctrl *s3c_ctrl, int num_ctrl)
+{
+	struct s3c_irq_intc *intc;
+	struct s3c24xx_irq_of_ctrl *ctrl;
+	struct irq_domain *domain;
+	void __iomem *reg_base;
+	int i;
+
+	reg_base = of_iomap(np, 0);
+	if (!reg_base) {
+		pr_err("irq-s3c24xx: could not map irq registers\n");
+		return -EINVAL;
+	}
+
+	domain = irq_domain_add_linear(np, num_ctrl * 32,
+						     &s3c24xx_irq_ops_of, NULL);
+	if (!domain) {
+		pr_err("irq: could not create irq-domain\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < num_ctrl; i++) {
+		ctrl = &s3c_ctrl[i];
+
+		pr_debug("irq: found controller %s\n", ctrl->name);
+
+		intc = kzalloc(sizeof(struct s3c_irq_intc), GFP_KERNEL);
+		if (!intc)
+			return -ENOMEM;
+
+		intc->domain = domain;
+		intc->irqs = kzalloc(sizeof(struct s3c_irq_data) * 32,
+				     GFP_KERNEL);
+		if (!intc->irqs) {
+			kfree(intc);
+			return -ENOMEM;
+		}
+
+		if (ctrl->parent) {
+			intc->reg_pending = reg_base + ctrl->offset;
+			intc->reg_mask = reg_base + ctrl->offset + 0x4;
+
+			if (*(ctrl->parent)) {
+				intc->parent = *(ctrl->parent);
+			} else {
+				pr_warn("irq: parent of %s missing\n",
+					ctrl->name);
+				kfree(intc->irqs);
+				kfree(intc);
+				continue;
+			}
+		} else {
+			intc->reg_pending = reg_base + ctrl->offset;
+			intc->reg_mask = reg_base + ctrl->offset + 0x08;
+			intc->reg_intpnd = reg_base + ctrl->offset + 0x10;
+		}
+
+		s3c24xx_clear_intc(intc);
+		s3c_intc[i] = intc;
+	}
+
+	set_handle_irq(s3c24xx_handle_irq);
+
+	return 0;
+}
+
+static struct s3c24xx_irq_of_ctrl s3c2410_ctrl[] = {
+	{
+		.name = "intc",
+		.offset = 0,
+	}, {
+		.name = "subintc",
+		.offset = 0x18,
+		.parent = &s3c_intc[0],
+	}
+};
+
+int __init s3c2410_init_intc_of(struct device_node *np,
+			struct device_node *interrupt_parent,
+			struct s3c24xx_irq_of_ctrl *ctrl, int num_ctrl)
+{
+	return s3c_init_intc_of(np, interrupt_parent,
+				s3c2410_ctrl, ARRAY_SIZE(s3c2410_ctrl));
+}
+IRQCHIP_DECLARE(s3c2410_irq, "samsung,s3c2410-irq", s3c2410_init_intc_of);
+
+static struct s3c24xx_irq_of_ctrl s3c2416_ctrl[] = {
+	{
+		.name = "intc",
+		.offset = 0,
+	}, {
+		.name = "subintc",
+		.offset = 0x18,
+		.parent = &s3c_intc[0],
+	}, {
+		.name = "intc2",
+		.offset = 0x40,
+	}
+};
+
+int __init s3c2416_init_intc_of(struct device_node *np,
+			struct device_node *interrupt_parent,
+			struct s3c24xx_irq_of_ctrl *ctrl, int num_ctrl)
+{
+	return s3c_init_intc_of(np, interrupt_parent,
+				s3c2416_ctrl, ARRAY_SIZE(s3c2416_ctrl));
 }
+IRQCHIP_DECLARE(s3c2416_irq, "samsung,s3c2416-irq", s3c2416_init_intc_of);
 #endif