[PATCH 15/20] ARM: Exynos: Add irq_domain support for gpio wakeup interrupts

[thomas.abraham@linaro.org (Thomas Abraham)]

Add a irq_domain for all the 32 gpio external wakeup interrupt sources.
Since there are users of fixed linux irq numbers of the external wakeup
interrupts, the legacy mapping is used for the irq domain. The fixups
required to use irq domain based interrupt mapping is also included.

Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
---
 arch/arm/mach-exynos/common.c                 |   67 +++++++++++++++++--------
 arch/arm/mach-exynos/include/mach/regs-gpio.h |    4 +-
 2 files changed, 48 insertions(+), 23 deletions(-)

diff --git a/arch/arm/mach-exynos/common.c b/arch/arm/mach-exynos/common.c
index 810f804..0d69412 100644
--- a/arch/arm/mach-exynos/common.c
+++ b/arch/arm/mach-exynos/common.c
@@ -752,6 +752,9 @@ static DEFINE_SPINLOCK(eint_lock);
 
 static unsigned int eint0_15_data[16];
 
+#define EXYNOS_EINT_NR 32
+static struct irq_domain *irq_domain;
+
 static inline int exynos4_irq_to_gpio(unsigned int irq)
 {
 	if (irq < IRQ_EINT(0))
@@ -842,9 +845,9 @@ static inline void exynos_irq_eint_mask(struct irq_data *data)
 	u32 mask;
 
 	spin_lock(&eint_lock);
-	mask = __raw_readl(EINT_MASK(exynos_eint_base, data->irq));
-	mask |= EINT_OFFSET_BIT(data->irq);
-	__raw_writel(mask, EINT_MASK(exynos_eint_base, data->irq));
+	mask = __raw_readl(EINT_MASK(exynos_eint_base, data->hwirq));
+	mask |= EINT_OFFSET_BIT(data->hwirq);
+	__raw_writel(mask, EINT_MASK(exynos_eint_base, data->hwirq));
 	spin_unlock(&eint_lock);
 }
 
@@ -853,16 +856,16 @@ static void exynos_irq_eint_unmask(struct irq_data *data)
 	u32 mask;
 
 	spin_lock(&eint_lock);
-	mask = __raw_readl(EINT_MASK(exynos_eint_base, data->irq));
-	mask &= ~(EINT_OFFSET_BIT(data->irq));
-	__raw_writel(mask, EINT_MASK(exynos_eint_base, data->irq));
+	mask = __raw_readl(EINT_MASK(exynos_eint_base, data->hwirq));
+	mask &= ~(EINT_OFFSET_BIT(data->hwirq));
+	__raw_writel(mask, EINT_MASK(exynos_eint_base, data->hwirq));
 	spin_unlock(&eint_lock);
 }
 
 static inline void exynos_irq_eint_ack(struct irq_data *data)
 {
-	__raw_writel(EINT_OFFSET_BIT(data->irq),
-		     EINT_PEND(exynos_eint_base, data->irq));
+	__raw_writel(EINT_OFFSET_BIT(data->hwirq),
+		     EINT_PEND(exynos_eint_base, data->hwirq));
 }
 
 static void exynos_irq_eint_maskack(struct irq_data *data)
@@ -873,7 +876,7 @@ static void exynos_irq_eint_maskack(struct irq_data *data)
 
 static int exynos_irq_eint_set_type(struct irq_data *data, unsigned int type)
 {
-	int offs = EINT_OFFSET(data->irq);
+	int offs = data->hwirq;
 	int shift;
 	u32 ctrl, mask;
 	u32 newvalue = 0;
@@ -908,10 +911,10 @@ static int exynos_irq_eint_set_type(struct irq_data *data, unsigned int type)
 	mask = 0x7 << shift;
 
 	spin_lock(&eint_lock);
-	ctrl = __raw_readl(EINT_CON(exynos_eint_base, data->irq));
+	ctrl = __raw_readl(EINT_CON(exynos_eint_base, data->hwirq));
 	ctrl &= ~mask;
 	ctrl |= newvalue << shift;
-	__raw_writel(ctrl, EINT_CON(exynos_eint_base, data->irq));
+	__raw_writel(ctrl, EINT_CON(exynos_eint_base, data->hwirq));
 	spin_unlock(&eint_lock);
 
 	if (soc_is_exynos5250())
@@ -955,7 +958,7 @@ static inline void exynos_irq_demux_eint(unsigned int start)
 
 	while (status) {
 		irq = fls(status) - 1;
-		generic_handle_irq(irq + start);
+		generic_handle_irq(irq_find_mapping(irq_domain, irq + start));
 		status &= ~(1 << irq);
 	}
 }
@@ -964,8 +967,8 @@ static void exynos_irq_demux_eint16_31(unsigned int irq, struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_get_chip(irq);
 	chained_irq_enter(chip, desc);
-	exynos_irq_demux_eint(IRQ_EINT(16));
-	exynos_irq_demux_eint(IRQ_EINT(24));
+	exynos_irq_demux_eint(16);
+	exynos_irq_demux_eint(24);
 	chained_irq_exit(chip, desc);
 }
 
@@ -973,6 +976,7 @@ static void exynos_irq_eint0_15(unsigned int irq, struct irq_desc *desc)
 {
 	u32 *irq_data = irq_get_handler_data(irq);
 	struct irq_chip *chip = irq_get_chip(irq);
+	int eint_irq;
 
 	chained_irq_enter(chip, desc);
 	chip->irq_mask(&desc->irq_data);
@@ -980,15 +984,28 @@ static void exynos_irq_eint0_15(unsigned int irq, struct irq_desc *desc)
 	if (chip->irq_ack)
 		chip->irq_ack(&desc->irq_data);
 
-	generic_handle_irq(*irq_data);
+	eint_irq = irq_find_mapping(irq_domain, *irq_data);
+	generic_handle_irq(eint_irq);
 
 	chip->irq_unmask(&desc->irq_data);
 	chained_irq_exit(chip, desc);
 }
 
+static int exynos_eint_irq_domain_map(struct irq_domain *d, unsigned int irq,
+					irq_hw_number_t hw)
+{
+	irq_set_chip_and_handler(irq, &exynos_irq_eint, handle_level_irq);
+	set_irq_flags(irq, IRQF_VALID);
+	return 0;
+}
+
+static struct irq_domain_ops exynos_eint_irq_domain_ops = {
+	.map = exynos_eint_irq_domain_map,
+};
+
 static int __init exynos_init_irq_eint(void)
 {
-	int irq, *src_int;
+	int irq, *src_int, irq_base;
 	unsigned int paddr;
 
 	paddr = soc_is_exynos5250() ? EXYNOS5_PA_GPIO1 : EXYNOS4_PA_GPIO2;
@@ -998,16 +1015,24 @@ static int __init exynos_init_irq_eint(void)
 		return -ENXIO;
 	}
 
-	for (irq = 0 ; irq <= 31 ; irq++) {
-		irq_set_chip_and_handler(IRQ_EINT(irq), &exynos_irq_eint,
-					 handle_level_irq);
-		set_irq_flags(IRQ_EINT(irq), IRQF_VALID);
+	irq_base = irq_alloc_descs(IRQ_EINT(0), 1, EXYNOS_EINT_NR, 0);
+	if (IS_ERR_VALUE(irq_base)) {
+		irq_base = IRQ_EINT(0);
+		pr_warning("%s: irq desc alloc failed. Continuing with %d as "
+				"linux irq base\n", __func__, irq_base);
+	}
+
+	irq_domain = irq_domain_add_legacy(NULL, EXYNOS_EINT_NR, irq_base, 0,
+					 &exynos_eint_irq_domain_ops, NULL);
+	if (WARN_ON(!irq_domain)) {
+		pr_warning("%s: irq domain init failed\n", __func__);
+		return 0;
 	}
 
 	irq_set_chained_handler(EXYNOS_IRQ_EINT16_31, exynos_irq_demux_eint16_31);
 
 	for (irq = 0 ; irq <= 15; irq++) {
-		eint0_15_data[irq] = IRQ_EINT(irq);
+		eint0_15_data[irq] = irq;
 		src_int = soc_is_exynos5250() ? exynos5_eint0_15_src_int :
 						exynos4_eint0_15_src_int;
 		irq_set_handler_data(src_int[irq], &eint0_15_data[irq]);
diff --git a/arch/arm/mach-exynos/include/mach/regs-gpio.h b/arch/arm/mach-exynos/include/mach/regs-gpio.h
index e4b5b60..24bf4ec 100644
--- a/arch/arm/mach-exynos/include/mach/regs-gpio.h
+++ b/arch/arm/mach-exynos/include/mach/regs-gpio.h
@@ -16,13 +16,13 @@
 #include <mach/map.h>
 #include <mach/irqs.h>
 
-#define EINT_REG_NR(x)			(EINT_OFFSET(x) >> 3)
+#define EINT_REG_NR(x)			((x) >> 3)
 #define EINT_CON(b, x)			(b + 0xE00 + (EINT_REG_NR(x) * 4))
 #define EINT_FLTCON(b, x)		(b + 0xE80 + (EINT_REG_NR(x) * 4))
 #define EINT_MASK(b, x)			(b + 0xF00 + (EINT_REG_NR(x) * 4))
 #define EINT_PEND(b, x)			(b + 0xF40 + (EINT_REG_NR(x) * 4))
 
-#define EINT_OFFSET_BIT(x)		(1 << (EINT_OFFSET(x) & 0x7))
+#define EINT_OFFSET_BIT(x)		(1 << ((x) & 0x7))
 
 /* compatibility for plat-s5p/irq-pm.c */
 #define EXYNOS4_EINT40CON		(S5P_VA_GPIO2 + 0xE00)
-- 
1.7.5.4