[patch 1/2] xtensa: allow platform and variant to initialize own irq chips

[patch 1/2] xtensa: allow platform and variant to initialize own irq chips

[Daniel Glöckner]

There was already a PLATFORM_NR_IRQS define, which is now accompanied
by a VARIANT_NR_IRQS. To be able to initialize these interrupts,
init_IRQ now calls variant and platform specific hooks.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
---
 arch/xtensa/include/asm/irq.h                     |   21 ++++++++++++++++++---
 arch/xtensa/kernel/irq.c                          |    3 +++
 arch/xtensa/variants/dc232b/include/variant/irq.h |    4 ++++
 arch/xtensa/variants/fsf/include/variant/irq.h    |    4 ++++
 4 files changed, 29 insertions(+), 3 deletions(-)
 create mode 100644 arch/xtensa/variants/dc232b/include/variant/irq.h
 create mode 100644 arch/xtensa/variants/fsf/include/variant/irq.h

diff --git a/arch/xtensa/include/asm/irq.h b/arch/xtensa/include/asm/irq.h
index dfac82d..c3c10a7 100644
--- a/arch/xtensa/include/asm/irq.h
+++ b/arch/xtensa/include/asm/irq.h
@@ -11,21 +11,36 @@
 #ifndef _XTENSA_IRQ_H
 #define _XTENSA_IRQ_H
 
+#include <linux/init.h>
 #include <platform/hardware.h>
 #include <variant/core.h>
 
-#ifdef CONFIG_VARIANT_IRQ_SWITCH
 #include <variant/irq.h>
-#else
+#ifndef CONFIG_VARIANT_IRQ_SWITCH
 static inline void variant_irq_enable(unsigned int irq) { }
 static inline void variant_irq_disable(unsigned int irq) { }
 #endif
 
+#ifndef VARIANT_NR_IRQS
+# define VARIANT_NR_IRQS 0
+#endif
 #ifndef PLATFORM_NR_IRQS
 # define PLATFORM_NR_IRQS 0
 #endif
 #define XTENSA_NR_IRQS XCHAL_NUM_INTERRUPTS
-#define NR_IRQS (XTENSA_NR_IRQS + PLATFORM_NR_IRQS)
+#define NR_IRQS (XTENSA_NR_IRQS + VARIANT_NR_IRQS + PLATFORM_NR_IRQS)
+
+#if VARIANT_NR_IRQS == 0
+static inline void variant_init_IRQ(void) { }
+#else
+void variant_init_IRQ(void) __init;
+#endif
+
+#if PLATFORM_NR_IRQS == 0
+static inline void platform_init_IRQ(void) { }
+#else
+void platform_init_IRQ(void) __init;
+#endif
 
 static __inline__ int irq_canonicalize(int irq)
 {
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c
index 2068445..89bb970 100644
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -197,4 +197,7 @@ void __init init_IRQ(void)
 	}
 
 	cached_irq_mask = 0;
+
+	variant_init_IRQ();
+	platform_init_IRQ();
 }
diff --git a/arch/xtensa/variants/dc232b/include/variant/irq.h b/arch/xtensa/variants/dc232b/include/variant/irq.h
new file mode 100644
index 0000000..070b9f5
--- /dev/null
+++ b/arch/xtensa/variants/dc232b/include/variant/irq.h
@@ -0,0 +1,4 @@
+#ifndef __XTENSA_VARIANT_IRQ_H
+#define __XTENSA_VARIANT_IRQ_H
+
+#endif
diff --git a/arch/xtensa/variants/fsf/include/variant/irq.h b/arch/xtensa/variants/fsf/include/variant/irq.h
new file mode 100644
index 0000000..070b9f5
--- /dev/null
+++ b/arch/xtensa/variants/fsf/include/variant/irq.h
@@ -0,0 +1,4 @@
+#ifndef __XTENSA_VARIANT_IRQ_H
+#define __XTENSA_VARIANT_IRQ_H
+
+#endif
-- 
1.6.2.107.ge47ee

[patch 2/2] xtensa: support s6000 gpio irqs and alternate function selection

[Daniel Glöckner]

The patch implements an irq chip to handle interrupts via gpio.

As interrupts may be needed very early it is up to platform setup code
to initialize gpio by calling s6_setup_gpio. Its parameter is a bitmask
of those pins that should be configured for their alternative function.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
---
 arch/xtensa/include/asm/gpio.h                    |    8 +-
 arch/xtensa/platforms/s6105/setup.c               |    3 +
 arch/xtensa/variants/s6000/gpio.c                 |  164 ++++++++++++++++++++-
 arch/xtensa/variants/s6000/include/variant/gpio.h |    6 +
 arch/xtensa/variants/s6000/include/variant/irq.h  |    1 +
 5 files changed, 176 insertions(+), 6 deletions(-)
 create mode 100644 arch/xtensa/variants/s6000/include/variant/gpio.h

diff --git a/arch/xtensa/include/asm/gpio.h b/arch/xtensa/include/asm/gpio.h
index 0763b07..a8c9fc4 100644
--- a/arch/xtensa/include/asm/gpio.h
+++ b/arch/xtensa/include/asm/gpio.h
@@ -38,14 +38,14 @@ static inline int gpio_cansleep(unsigned int gpio)
 	return __gpio_cansleep(gpio);
 }
 
-/*
- * Not implemented, yet.
- */
 static inline int gpio_to_irq(unsigned int gpio)
 {
-	return -ENOSYS;
+	return __gpio_to_irq(gpio);
 }
 
+/*
+ * Not implemented, yet.
+ */
 static inline int irq_to_gpio(unsigned int irq)
 {
 	return -EINVAL;
diff --git a/arch/xtensa/platforms/s6105/setup.c b/arch/xtensa/platforms/s6105/setup.c
index ae041d5..1dbf133 100644
--- a/arch/xtensa/platforms/s6105/setup.c
+++ b/arch/xtensa/platforms/s6105/setup.c
@@ -10,6 +10,8 @@
 #include <asm/bootparam.h>
 
 #include <variant/hardware.h>
+#include <variant/gpio.h>
+
 #include <platform/gpio.h>
 
 void platform_halt(void)
@@ -47,6 +49,7 @@ void __init platform_setup(char **cmdline)
 
 void __init platform_init(bp_tag_t *first)
 {
+	s6_setup_gpio(0);
 	gpio_request(GPIO_LED1_NGREEN, "led1_green");
 	gpio_request(GPIO_LED1_RED, "led1_red");
 	gpio_direction_output(GPIO_LED1_NGREEN, 1);
diff --git a/arch/xtensa/variants/s6000/gpio.c b/arch/xtensa/variants/s6000/gpio.c
index 33a8d95..d71c8c2 100644
--- a/arch/xtensa/variants/s6000/gpio.c
+++ b/arch/xtensa/variants/s6000/gpio.c
@@ -4,15 +4,20 @@
  * Copyright (c) 2009 emlix GmbH
  * Authors:	Oskar Schirmer <os@emlix.com>
  *		Johannes Weiner <jw@emlix.com>
+ *		Daniel Gloeckner <dg@emlix.com>
  */
+#include <linux/bitops.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/gpio.h>
 
 #include <variant/hardware.h>
 
+#define IRQ_BASE XTENSA_NR_IRQS
+
 #define S6_GPIO_DATA		0x000
 #define S6_GPIO_IS		0x404
 #define S6_GPIO_IBE		0x408
@@ -52,20 +57,175 @@ static void set(struct gpio_chip *chip, unsigned int off, int val)
 	writeb(val ? ~0 : 0, S6_REG_GPIO + S6_GPIO_DATA + S6_GPIO_OFFSET(off));
 }
 
+static int to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	if (offset < 8)
+		return offset + IRQ_BASE;
+	return -EINVAL;
+}
+
 static struct gpio_chip gpiochip = {
 	.owner = THIS_MODULE,
 	.direction_input = direction_input,
 	.get = get,
 	.direction_output = direction_output,
 	.set = set,
+	.to_irq = to_irq,
 	.base = 0,
 	.ngpio = 24,
 	.can_sleep = 0, /* no blocking io needed */
 	.exported = 0, /* no exporting to userspace */
 };
 
-static int gpio_init(void)
+int __init s6_setup_gpio(u32 afsel)
 {
+	writeb(afsel, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_AFSEL);
+	writeb(afsel >> 8, S6_REG_GPIO + S6_GPIO_BANK(1) + S6_GPIO_AFSEL);
+	writeb(afsel >> 16, S6_REG_GPIO + S6_GPIO_BANK(2) + S6_GPIO_AFSEL);
 	return gpiochip_add(&gpiochip);
 }
-device_initcall(gpio_init);
+
+static void ack(unsigned int irq)
+{
+	writeb(1 << (irq - IRQ_BASE), S6_REG_GPIO + S6_GPIO_IC);
+}
+
+static void mask(unsigned int irq)
+{
+	u8 r = readb(S6_REG_GPIO + S6_GPIO_IE);
+	r &= ~(1 << (irq - IRQ_BASE));
+	writeb(r, S6_REG_GPIO + S6_GPIO_IE);
+}
+
+static void unmask(unsigned int irq)
+{
+	u8 m = readb(S6_REG_GPIO + S6_GPIO_IE);
+	m |= 1 << (irq - IRQ_BASE);
+	writeb(m, S6_REG_GPIO + S6_GPIO_IE);
+}
+
+static int set_type(unsigned int irq, unsigned int type)
+{
+	const u8 m = 1 << (irq - IRQ_BASE);
+	irq_flow_handler_t handler;
+	struct irq_desc *desc;
+	u8 reg;
+
+	if (type == IRQ_TYPE_PROBE) {
+		if ((readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_AFSEL) & m)
+		    || (readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IE) & m)
+		    || readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_DIR
+			      + S6_GPIO_MASK(irq - IRQ_BASE)))
+			return 0;
+		type = IRQ_TYPE_EDGE_BOTH;
+	}
+
+	reg = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IS);
+	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) {
+		reg |= m;
+		handler = handle_level_irq;
+	} else {
+		reg = ~m;
+		handler = handle_edge_irq;
+	}
+	writeb(reg, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IS);
+	desc = irq_to_desc(irq);
+	desc->handle_irq = handler;
+
+	reg = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IEV);
+	if (type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_EDGE_RISING))
+		reg |= m;
+	else
+		reg &= ~m;
+	writeb(reg, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IEV);
+
+	reg = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IBE);
+	if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
+		reg |= m;
+	else
+		reg &= ~m;
+	writeb(reg, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IBE);
+	return 0;
+}
+
+static struct irq_chip gpioirqs = {
+	.name = "GPIO",
+	.ack = ack,
+	.mask = mask,
+	.unmask = unmask,
+	.set_type = set_type,
+};
+
+static u8 demux_masks[4];
+
+static void demux_irqs(unsigned int irq, struct irq_desc *desc)
+{
+	u8 *mask = get_irq_desc_data(desc);
+	u8 pending;
+	int cirq;
+
+	desc->chip->mask(irq);
+	desc->chip->ack(irq);
+	pending = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_MIS) & *mask;
+	cirq = IRQ_BASE - 1;
+	while (pending) {
+		int n = ffs(pending);
+		cirq += n;
+		pending >>= n;
+		generic_handle_irq(cirq);
+	}
+	desc->chip->unmask(irq);
+}
+
+extern const signed char *platform_irq_mappings[XTENSA_NR_IRQS];
+
+void __init variant_init_IRQ(void)
+{
+	int irq, n;
+	writeb(0, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IE);
+	for (irq = n = 0; irq < XTENSA_NR_IRQS; irq++) {
+		const signed char *mapping = platform_irq_mappings[irq];
+		int alone = 1;
+		u8 mask;
+		if (!mapping)
+			continue;
+		for(mask = 0; *mapping != -1; mapping++)
+			switch (*mapping) {
+			case S6_INTC_GPIO(0):
+				mask |= 1 << 0;
+				break;
+			case S6_INTC_GPIO(1):
+				mask |= 1 << 1;
+				break;
+			case S6_INTC_GPIO(2):
+				mask |= 1 << 2;
+				break;
+			case S6_INTC_GPIO(3):
+				mask |= 0x1f << 3;
+				break;
+			default:
+				alone = 0;
+			}
+		if (mask) {
+			int cirq, i;
+			if (!alone) {
+				printk(KERN_ERR "chained irq chips can't share"
+					" parent irq %i\n", irq);
+				continue;
+			}
+			demux_masks[n] = mask;
+			cirq = IRQ_BASE - 1;
+			do {
+				i = ffs(mask);
+				cirq += i;
+				mask >>= i;
+				set_irq_chip(cirq, &gpioirqs);
+				set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
+			} while (mask);
+			set_irq_data(irq, demux_masks + n);
+			set_irq_chained_handler(irq, demux_irqs);
+			if (++n == ARRAY_SIZE(demux_masks))
+				break;
+		}
+	}
+}
diff --git a/arch/xtensa/variants/s6000/include/variant/gpio.h b/arch/xtensa/variants/s6000/include/variant/gpio.h
new file mode 100644
index 0000000..70cb330
--- /dev/null
+++ b/arch/xtensa/variants/s6000/include/variant/gpio.h
@@ -0,0 +1,6 @@
+#ifndef __XTENSA_VARIANT_S6000_GPIO_H
+#define __XTENSA_VARIANT_S6000_GPIO_H
+
+int s6_setup_gpio(u32 afsel) __init;
+
+#endif
diff --git a/arch/xtensa/variants/s6000/include/variant/irq.h b/arch/xtensa/variants/s6000/include/variant/irq.h
index fa031cb..55403d1 100644
--- a/arch/xtensa/variants/s6000/include/variant/irq.h
+++ b/arch/xtensa/variants/s6000/include/variant/irq.h
@@ -2,6 +2,7 @@
 #define __XTENSA_S6000_IRQ_H
 
 #define NO_IRQ		(-1)
+#define VARIANT_NR_IRQS 8 /* GPIO interrupts */
 
 extern void variant_irq_enable(unsigned int irq);
 extern void variant_irq_disable(unsigned int irq);
-- 
1.6.2.107.ge47ee

[PATCH v2 1/2] xtensa: allow variant to initialize own irq chips

[Daniel Glöckner]

There was already a PLATFORM_NR_IRQS define, which is now accompanied
by a VARIANT_NR_IRQS. To be able to initialize these interrupts,
init_IRQ now calls a variant specific hook.

Changes compared to v1:
- adapted to new CONFIG_VARIANT_IRQ_EXT
- removed definition and call of platform_init_IRQ as there already
  is a platform_init_irq defined in asm/platform.h with a weak default
  in kernel/platform.c
- renamed variant_init_IRQ to variant_init_irq

Note that I could not find the call site of platform_init_irq although
it is stated in platform.h that it is called from init_IRQ.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
---
 arch/xtensa/include/asm/irq.h |   12 +++++++++++-
 arch/xtensa/kernel/irq.c      |    2 ++
 2 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/arch/xtensa/include/asm/irq.h b/arch/xtensa/include/asm/irq.h
index 4a39bb5..f10ee86 100644
--- a/arch/xtensa/include/asm/irq.h
+++ b/arch/xtensa/include/asm/irq.h
@@ -11,6 +11,7 @@
 #ifndef _XTENSA_IRQ_H
 #define _XTENSA_IRQ_H
 
+#include <linux/init.h>
 #include <platform/hardware.h>
 #include <variant/core.h>
 
@@ -23,11 +24,20 @@ static inline void variant_irq_enable(unsigned int irq) { }
 static inline void variant_irq_disable(unsigned int irq) { }
 #endif
 
+#ifndef VARIANT_NR_IRQS
+# define VARIANT_NR_IRQS 0
+#endif
 #ifndef PLATFORM_NR_IRQS
 # define PLATFORM_NR_IRQS 0
 #endif
 #define XTENSA_NR_IRQS XCHAL_NUM_INTERRUPTS
-#define NR_IRQS (XTENSA_NR_IRQS + PLATFORM_NR_IRQS)
+#define NR_IRQS (XTENSA_NR_IRQS + VARIANT_NR_IRQS + PLATFORM_NR_IRQS)
+
+#if VARIANT_NR_IRQS == 0
+static inline void variant_init_irq(void) { }
+#else
+void variant_init_irq(void) __init;
+#endif
 
 static __inline__ int irq_canonicalize(int irq)
 {
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c
index a36c85e..a1badb3 100644
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -197,4 +197,6 @@ void __init init_IRQ(void)
 	}
 
 	cached_irq_mask = 0;
+
+	variant_init_irq();
 }
-- 
1.6.1.3

[PATCH v2 2/2] xtensa: support s6000 gpio irqs and alternate function selection

[Daniel Glöckner]

Implement an irq chip to handle interrupts via gpio.  The GPIO chip
initialization function now takes a bitmask denoting pins that should
be configured for their alternate function.

changes compared to v1:
- fixed bug on edge interrupt configuration
- accommodated to function name change
- moved definition of VARIANT_NR_IRQS to this patch
- renamed __XTENSA_S6000_IRQ_H to _XTENSA_S6000_IRQ_H as requested

Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Johannes Weiner <jw@emlix.com>
---
 arch/xtensa/include/asm/gpio.h                    |    8 +-
 arch/xtensa/platforms/s6105/setup.c               |    2 +-
 arch/xtensa/variants/s6000/gpio.c                 |  163 ++++++++++++++++++++-
 arch/xtensa/variants/s6000/include/variant/gpio.h |    2 +-
 arch/xtensa/variants/s6000/include/variant/irq.h  |    5 +-
 5 files changed, 171 insertions(+), 9 deletions(-)

diff --git a/arch/xtensa/include/asm/gpio.h b/arch/xtensa/include/asm/gpio.h
index 0763b07..a8c9fc4 100644
--- a/arch/xtensa/include/asm/gpio.h
+++ b/arch/xtensa/include/asm/gpio.h
@@ -38,14 +38,14 @@ static inline int gpio_cansleep(unsigned int gpio)
 	return __gpio_cansleep(gpio);
 }
 
-/*
- * Not implemented, yet.
- */
 static inline int gpio_to_irq(unsigned int gpio)
 {
-	return -ENOSYS;
+	return __gpio_to_irq(gpio);
 }
 
+/*
+ * Not implemented, yet.
+ */
 static inline int irq_to_gpio(unsigned int irq)
 {
 	return -EINVAL;
diff --git a/arch/xtensa/platforms/s6105/setup.c b/arch/xtensa/platforms/s6105/setup.c
index 855ddea..95fa23c 100644
--- a/arch/xtensa/platforms/s6105/setup.c
+++ b/arch/xtensa/platforms/s6105/setup.c
@@ -49,7 +49,7 @@ void __init platform_setup(char **cmdline)
 
 void __init platform_init(bp_tag_t *first)
 {
-	s6_gpio_init();
+	s6_gpio_init(0);
 	gpio_request(GPIO_LED1_NGREEN, "led1_green");
 	gpio_request(GPIO_LED1_RED, "led1_red");
 	gpio_direction_output(GPIO_LED1_NGREEN, 1);
diff --git a/arch/xtensa/variants/s6000/gpio.c b/arch/xtensa/variants/s6000/gpio.c
index 79317fd..380a70f 100644
--- a/arch/xtensa/variants/s6000/gpio.c
+++ b/arch/xtensa/variants/s6000/gpio.c
@@ -4,15 +4,20 @@
  * Copyright (c) 2009 emlix GmbH
  * Authors:	Oskar Schirmer <os@emlix.com>
  *		Johannes Weiner <jw@emlix.com>
+ *		Daniel Gloeckner <dg@emlix.com>
  */
+#include <linux/bitops.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/gpio.h>
 
 #include <variant/hardware.h>
 
+#define IRQ_BASE XTENSA_NR_IRQS
+
 #define S6_GPIO_DATA		0x000
 #define S6_GPIO_IS		0x404
 #define S6_GPIO_IBE		0x408
@@ -52,19 +57,175 @@ static void set(struct gpio_chip *chip, unsigned int off, int val)
 	writeb(val ? ~0 : 0, S6_REG_GPIO + S6_GPIO_DATA + S6_GPIO_OFFSET(off));
 }
 
+static int to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	if (offset < 8)
+		return offset + IRQ_BASE;
+	return -EINVAL;
+}
+
 static struct gpio_chip gpiochip = {
 	.owner = THIS_MODULE,
 	.direction_input = direction_input,
 	.get = get,
 	.direction_output = direction_output,
 	.set = set,
+	.to_irq = to_irq,
 	.base = 0,
 	.ngpio = 24,
 	.can_sleep = 0, /* no blocking io needed */
 	.exported = 0, /* no exporting to userspace */
 };
 
-int s6_gpio_init(void)
+int s6_gpio_init(u32 afsel)
 {
+	writeb(afsel, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_AFSEL);
+	writeb(afsel >> 8, S6_REG_GPIO + S6_GPIO_BANK(1) + S6_GPIO_AFSEL);
+	writeb(afsel >> 16, S6_REG_GPIO + S6_GPIO_BANK(2) + S6_GPIO_AFSEL);
 	return gpiochip_add(&gpiochip);
 }
+
+static void ack(unsigned int irq)
+{
+	writeb(1 << (irq - IRQ_BASE), S6_REG_GPIO + S6_GPIO_IC);
+}
+
+static void mask(unsigned int irq)
+{
+	u8 r = readb(S6_REG_GPIO + S6_GPIO_IE);
+	r &= ~(1 << (irq - IRQ_BASE));
+	writeb(r, S6_REG_GPIO + S6_GPIO_IE);
+}
+
+static void unmask(unsigned int irq)
+{
+	u8 m = readb(S6_REG_GPIO + S6_GPIO_IE);
+	m |= 1 << (irq - IRQ_BASE);
+	writeb(m, S6_REG_GPIO + S6_GPIO_IE);
+}
+
+static int set_type(unsigned int irq, unsigned int type)
+{
+	const u8 m = 1 << (irq - IRQ_BASE);
+	irq_flow_handler_t handler;
+	struct irq_desc *desc;
+	u8 reg;
+
+	if (type == IRQ_TYPE_PROBE) {
+		if ((readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_AFSEL) & m)
+		    || (readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IE) & m)
+		    || readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_DIR
+			      + S6_GPIO_MASK(irq - IRQ_BASE)))
+			return 0;
+		type = IRQ_TYPE_EDGE_BOTH;
+	}
+
+	reg = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IS);
+	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) {
+		reg |= m;
+		handler = handle_level_irq;
+	} else {
+		reg &= ~m;
+		handler = handle_edge_irq;
+	}
+	writeb(reg, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IS);
+	desc = irq_to_desc(irq);
+	desc->handle_irq = handler;
+
+	reg = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IEV);
+	if (type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_EDGE_RISING))
+		reg |= m;
+	else
+		reg &= ~m;
+	writeb(reg, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IEV);
+
+	reg = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IBE);
+	if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
+		reg |= m;
+	else
+		reg &= ~m;
+	writeb(reg, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IBE);
+	return 0;
+}
+
+static struct irq_chip gpioirqs = {
+	.name = "GPIO",
+	.ack = ack,
+	.mask = mask,
+	.unmask = unmask,
+	.set_type = set_type,
+};
+
+static u8 demux_masks[4];
+
+static void demux_irqs(unsigned int irq, struct irq_desc *desc)
+{
+	u8 *mask = get_irq_desc_data(desc);
+	u8 pending;
+	int cirq;
+
+	desc->chip->mask(irq);
+	desc->chip->ack(irq);
+	pending = readb(S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_MIS) & *mask;
+	cirq = IRQ_BASE - 1;
+	while (pending) {
+		int n = ffs(pending);
+		cirq += n;
+		pending >>= n;
+		generic_handle_irq(cirq);
+	}
+	desc->chip->unmask(irq);
+}
+
+extern const signed char *platform_irq_mappings[XTENSA_NR_IRQS];
+
+void __init variant_init_irq(void)
+{
+	int irq, n;
+	writeb(0, S6_REG_GPIO + S6_GPIO_BANK(0) + S6_GPIO_IE);
+	for (irq = n = 0; irq < XTENSA_NR_IRQS; irq++) {
+		const signed char *mapping = platform_irq_mappings[irq];
+		int alone = 1;
+		u8 mask;
+		if (!mapping)
+			continue;
+		for(mask = 0; *mapping != -1; mapping++)
+			switch (*mapping) {
+			case S6_INTC_GPIO(0):
+				mask |= 1 << 0;
+				break;
+			case S6_INTC_GPIO(1):
+				mask |= 1 << 1;
+				break;
+			case S6_INTC_GPIO(2):
+				mask |= 1 << 2;
+				break;
+			case S6_INTC_GPIO(3):
+				mask |= 0x1f << 3;
+				break;
+			default:
+				alone = 0;
+			}
+		if (mask) {
+			int cirq, i;
+			if (!alone) {
+				printk(KERN_ERR "chained irq chips can't share"
+					" parent irq %i\n", irq);
+				continue;
+			}
+			demux_masks[n] = mask;
+			cirq = IRQ_BASE - 1;
+			do {
+				i = ffs(mask);
+				cirq += i;
+				mask >>= i;
+				set_irq_chip(cirq, &gpioirqs);
+				set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
+			} while (mask);
+			set_irq_data(irq, demux_masks + n);
+			set_irq_chained_handler(irq, demux_irqs);
+			if (++n == ARRAY_SIZE(demux_masks))
+				break;
+		}
+	}
+}
diff --git a/arch/xtensa/variants/s6000/include/variant/gpio.h b/arch/xtensa/variants/s6000/include/variant/gpio.h
index 8327f62..8484ab0 100644
--- a/arch/xtensa/variants/s6000/include/variant/gpio.h
+++ b/arch/xtensa/variants/s6000/include/variant/gpio.h
@@ -1,6 +1,6 @@
 #ifndef _XTENSA_VARIANT_S6000_GPIO_H
 #define _XTENSA_VARIANT_S6000_GPIO_H
 
-extern int s6_gpio_init(void);
+extern int s6_gpio_init(u32 afsel);
 
 #endif /* _XTENSA_VARIANT_S6000_GPIO_H */
diff --git a/arch/xtensa/variants/s6000/include/variant/irq.h b/arch/xtensa/variants/s6000/include/variant/irq.h
index bcd496d..1a69d33 100644
--- a/arch/xtensa/variants/s6000/include/variant/irq.h
+++ b/arch/xtensa/variants/s6000/include/variant/irq.h
@@ -1,7 +1,8 @@
-#ifndef __XTENSA_S6000_IRQ_H
-#define __XTENSA_S6000_IRQ_H
+#ifndef _XTENSA_S6000_IRQ_H
+#define _XTENSA_S6000_IRQ_H
 
 #define NO_IRQ		(-1)
+#define VARIANT_NR_IRQS 8 /* GPIO interrupts */
 
 #define VARIANT_HAS_IRQ_ENABLE
 extern void variant_irq_enable(unsigned int irq);
-- 
1.6.1.3