pinctrl: Add pinctrl-s3c64xx driver

This patch adds pinctrl-s3c64xx driver which implements pin control
interface for Samsung S3C64xx SoCs.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

5 files changed, 832 insertions, 0 deletions

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index ab7225e471ab..f910962baaa7 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -208,6 +208,11 @@ config PINCTRL_EXYNOS5440
 	select PINMUX
 	select PINCONF
 
+config PINCTRL_S3C64XX
+	bool "Samsung S3C64XX SoC pinctrl driver"
+	depends on ARCH_S3C64XX
+	select PINCTRL_SAMSUNG
+
 source "drivers/pinctrl/mvebu/Kconfig"
 source "drivers/pinctrl/sh-pfc/Kconfig"
 source "drivers/pinctrl/spear/Kconfig"
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 82db76c8abc1..988279ae23cd 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -41,6 +41,7 @@ obj-$(CONFIG_PINCTRL_COH901)	+= pinctrl-coh901.o
 obj-$(CONFIG_PINCTRL_SAMSUNG)	+= pinctrl-samsung.o
 obj-$(CONFIG_PINCTRL_EXYNOS)	+= pinctrl-exynos.o
 obj-$(CONFIG_PINCTRL_EXYNOS5440)	+= pinctrl-exynos5440.o
+obj-$(CONFIG_PINCTRL_S3C64XX)	+= pinctrl-s3c64xx.o
 obj-$(CONFIG_PINCTRL_XWAY)	+= pinctrl-xway.o
 obj-$(CONFIG_PINCTRL_LANTIQ)	+= pinctrl-lantiq.o
 
diff --git a/drivers/pinctrl/pinctrl-s3c64xx.c b/drivers/pinctrl/pinctrl-s3c64xx.c
new file mode 100644
index 000000000000..b5d1c4a0b73d
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-s3c64xx.c
@@ -0,0 +1,817 @@
+/*
+ * S3C64xx specific support for pinctrl-samsung driver.
+ *
+ * Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>
+ *
+ * Based on pinctrl-exynos.c, please see the file for original copyrights.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This file contains the Samsung S3C64xx specific information required by the
+ * the Samsung pinctrl/gpiolib driver. It also includes the implementation of
+ * external gpio and wakeup interrupt support.
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/irq.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+
+#include <asm/mach/irq.h>
+
+#include "pinctrl-samsung.h"
+
+#define NUM_EINT0		28
+#define NUM_EINT0_IRQ		4
+#define EINT_MAX_PER_REG	16
+#define EINT_MAX_PER_GROUP	16
+
+/* External GPIO and wakeup interrupt related definitions */
+#define SVC_GROUP_SHIFT		4
+#define SVC_GROUP_MASK		0xf
+#define SVC_NUM_MASK		0xf
+#define SVC_GROUP(x)		((x >> SVC_GROUP_SHIFT) & \
+						SVC_GROUP_MASK)
+
+#define EINT12CON_REG		0x200
+#define EINT12MASK_REG		0x240
+#define EINT12PEND_REG		0x260
+
+#define EINT_OFFS(i)		((i) % (2 * EINT_MAX_PER_GROUP))
+#define EINT_GROUP(i)		((i) / EINT_MAX_PER_GROUP)
+#define EINT_REG(g)		(4 * ((g) / 2))
+
+#define EINTCON_REG(i)		(EINT12CON_REG + EINT_REG(EINT_GROUP(i)))
+#define EINTMASK_REG(i)		(EINT12MASK_REG + EINT_REG(EINT_GROUP(i)))
+#define EINTPEND_REG(i)		(EINT12PEND_REG + EINT_REG(EINT_GROUP(i)))
+
+#define SERVICE_REG		0x284
+#define SERVICEPEND_REG		0x288
+
+#define EINT0CON0_REG		0x900
+#define EINT0MASK_REG		0x920
+#define EINT0PEND_REG		0x924
+
+/* S3C64xx specific external interrupt trigger types */
+#define EINT_LEVEL_LOW		0
+#define EINT_LEVEL_HIGH		1
+#define EINT_EDGE_FALLING	2
+#define EINT_EDGE_RISING	4
+#define EINT_EDGE_BOTH		6
+#define EINT_CON_MASK		0xF
+#define EINT_CON_LEN		4
+
+static struct samsung_pin_bank_type bank_type_4bit_off = {
+	.fld_width = { 4, 1, 2, 0, 2, 2, },
+	.reg_offset = { 0x00, 0x04, 0x08, 0, 0x0c, 0x10, },
+};
+
+static struct samsung_pin_bank_type bank_type_4bit_alive = {
+	.fld_width = { 4, 1, 2, },
+	.reg_offset = { 0x00, 0x04, 0x08, },
+};
+
+static struct samsung_pin_bank_type bank_type_4bit2_off = {
+	.fld_width = { 4, 1, 2, 0, 2, 2, },
+	.reg_offset = { 0x00, 0x08, 0x0c, 0, 0x10, 0x14, },
+};
+
+static struct samsung_pin_bank_type bank_type_4bit2_alive = {
+	.fld_width = { 4, 1, 2, },
+	.reg_offset = { 0x00, 0x08, 0x0c, },
+};
+
+static struct samsung_pin_bank_type bank_type_2bit_off = {
+	.fld_width = { 2, 1, 2, 0, 2, 2, },
+	.reg_offset = { 0x00, 0x04, 0x08, 0, 0x0c, 0x10, },
+};
+
+static struct samsung_pin_bank_type bank_type_2bit_alive = {
+	.fld_width = { 2, 1, 2, },
+	.reg_offset = { 0x00, 0x04, 0x08, },
+};
+
+#define PIN_BANK_4BIT(pins, reg, id)			\
+	{						\
+		.type		= &bank_type_4bit_off,	\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_NONE,	\
+		.name		= id			\
+	}
+
+#define PIN_BANK_4BIT_EINTG(pins, reg, id, eoffs)	\
+	{						\
+		.type		= &bank_type_4bit_off,	\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_GPIO,	\
+		.eint_func	= 7,			\
+		.eint_mask	= (1 << (pins)) - 1,	\
+		.eint_offset	= eoffs,		\
+		.name		= id			\
+	}
+
+#define PIN_BANK_4BIT_EINTW(pins, reg, id, eoffs, emask) \
+	{						\
+		.type		= &bank_type_4bit_alive,\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_WKUP,	\
+		.eint_func	= 3,			\
+		.eint_mask	= emask,		\
+		.eint_offset	= eoffs,		\
+		.name		= id			\
+	}
+
+#define PIN_BANK_4BIT2_EINTG(pins, reg, id, eoffs)	\
+	{						\
+		.type		= &bank_type_4bit2_off,	\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_GPIO,	\
+		.eint_func	= 7,			\
+		.eint_mask	= (1 << (pins)) - 1,	\
+		.eint_offset	= eoffs,		\
+		.name		= id			\
+	}
+
+#define PIN_BANK_4BIT2_EINTW(pins, reg, id, eoffs, emask) \
+	{						\
+		.type		= &bank_type_4bit2_alive,\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_WKUP,	\
+		.eint_func	= 3,			\
+		.eint_mask	= emask,		\
+		.eint_offset	= eoffs,		\
+		.name		= id			\
+	}
+
+#define PIN_BANK_4BIT2_ALIVE(pins, reg, id)		\
+	{						\
+		.type		= &bank_type_4bit2_alive,\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_NONE,	\
+		.name		= id			\
+	}
+
+#define PIN_BANK_2BIT(pins, reg, id)			\
+	{						\
+		.type		= &bank_type_2bit_off,	\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_NONE,	\
+		.name		= id			\
+	}
+
+#define PIN_BANK_2BIT_EINTG(pins, reg, id, eoffs, emask) \
+	{						\
+		.type		= &bank_type_2bit_off,	\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_GPIO,	\
+		.eint_func	= 3,			\
+		.eint_mask	= emask,		\
+		.eint_offset	= eoffs,		\
+		.name		= id			\
+	}
+
+#define PIN_BANK_2BIT_EINTW(pins, reg, id, eoffs)	\
+	{						\
+		.type		= &bank_type_2bit_alive,\
+		.pctl_offset	= reg,			\
+		.nr_pins	= pins,			\
+		.eint_type	= EINT_TYPE_WKUP,	\
+		.eint_func	= 2,			\
+		.eint_mask	= (1 << (pins)) - 1,	\
+		.eint_offset	= eoffs,		\
+		.name		= id			\
+	}
+
+/**
+ * struct s3c64xx_eint0_data: EINT0 common data
+ * @drvdata: pin controller driver data
+ * @domains: IRQ domains of particular EINT0 interrupts
+ * @pins: pin offsets inside of banks of particular EINT0 interrupts
+ */
+struct s3c64xx_eint0_data {
+	struct samsung_pinctrl_drv_data *drvdata;
+	struct irq_domain *domains[NUM_EINT0];
+	u8 pins[NUM_EINT0];
+};
+
+/**
+ * struct s3c64xx_eint0_domain_data: EINT0 per-domain data
+ * @bank: pin bank related to the domain
+ * @eints: EINT0 interrupts related to the domain
+ */
+struct s3c64xx_eint0_domain_data {
+	struct samsung_pin_bank *bank;
+	u8 eints[];
+};
+
+/**
+ * struct s3c64xx_eint_gpio_data: GPIO EINT data
+ * @drvdata: pin controller driver data
+ * @domains: array of domains related to EINT interrupt groups
+ */
+struct s3c64xx_eint_gpio_data {
+	struct samsung_pinctrl_drv_data *drvdata;
+	struct irq_domain *domains[];
+};
+
+/*
+ * Common functions for S3C64xx EINT configuration
+ */
+
+static int s3c64xx_irq_get_trigger(unsigned int type)
+{
+	int trigger;
+
+	switch (type) {
+	case IRQ_TYPE_EDGE_RISING:
+		trigger = EINT_EDGE_RISING;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		trigger = EINT_EDGE_FALLING;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		trigger = EINT_EDGE_BOTH;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		trigger = EINT_LEVEL_HIGH;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		trigger = EINT_LEVEL_LOW;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return trigger;
+}
+
+static void s3c64xx_irq_set_handler(unsigned int irq, unsigned int type)
+{
+	/* Edge- and level-triggered interrupts need different handlers */
+	if (type & IRQ_TYPE_EDGE_BOTH)
+		__irq_set_handler_locked(irq, handle_edge_irq);
+	else
+		__irq_set_handler_locked(irq, handle_level_irq);
+}
+
+static void s3c64xx_irq_set_function(struct samsung_pinctrl_drv_data *d,
+					struct samsung_pin_bank *bank, int pin)
+{
+	struct samsung_pin_bank_type *bank_type = bank->type;
+	unsigned long flags;
+	void __iomem *reg;
+	u8 shift;
+	u32 mask;
+	u32 val;
+
+	/* Make sure that pin is configured as interrupt */
+	reg = d->virt_base + bank->pctl_offset;
+	shift = pin;
+	if (bank_type->fld_width[PINCFG_TYPE_FUNC] * shift >= 32) {
+		/* 4-bit bank type with 2 con regs */
+		reg += 4;
+		shift -= 8;
+	}
+
+	shift = shift * bank_type->fld_width[PINCFG_TYPE_FUNC];
+	mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
+
+	spin_lock_irqsave(&bank->slock, flags);
+
+	val = readl(reg);
+	val &= ~(mask << shift);
+	val |= bank->eint_func << shift;
+	writel(val, reg);
+
+	spin_unlock_irqrestore(&bank->slock, flags);
+}
+
+/*
+ * Functions for EINT GPIO configuration (EINT groups 1-9)
+ */
+
+static inline void s3c64xx_gpio_irq_set_mask(struct irq_data *irqd, bool mask)
+{
+	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
+	unsigned char index = EINT_OFFS(bank->eint_offset) + irqd->hwirq;
+	void __iomem *reg = d->virt_base + EINTMASK_REG(bank->eint_offset);
+	u32 val;
+
+	val = readl(reg);
+	if (mask)
+		val |= 1 << index;
+	else
+		val &= ~(1 << index);
+	writel(val, reg);
+}
+
+static void s3c64xx_gpio_irq_unmask(struct irq_data *irqd)
+{
+	s3c64xx_gpio_irq_set_mask(irqd, false);
+}
+
+static void s3c64xx_gpio_irq_mask(struct irq_data *irqd)
+{
+	s3c64xx_gpio_irq_set_mask(irqd, true);
+}
+
+static void s3c64xx_gpio_irq_ack(struct irq_data *irqd)
+{
+	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
+	unsigned char index = EINT_OFFS(bank->eint_offset) + irqd->hwirq;
+	void __iomem *reg = d->virt_base + EINTPEND_REG(bank->eint_offset);
+
+	writel(1 << index, reg);
+}
+
+static int s3c64xx_gpio_irq_set_type(struct irq_data *irqd, unsigned int type)
+{
+	struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd);
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
+	void __iomem *reg;
+	int trigger;
+	u8 shift;
+	u32 val;
+
+	trigger = s3c64xx_irq_get_trigger(type);
+	if (trigger < 0) {
+		pr_err("unsupported external interrupt type\n");
+		return -EINVAL;
+	}
+
+	s3c64xx_irq_set_handler(irqd->irq, type);
+
+	/* Set up interrupt trigger */
+	reg = d->virt_base + EINTCON_REG(bank->eint_offset);
+	shift = EINT_OFFS(bank->eint_offset) + irqd->hwirq;
+	shift = 4 * (shift / 4); /* 4 EINTs per trigger selector */
+
+	val = readl(reg);
+	val &= ~(EINT_CON_MASK << shift);
+	val |= trigger << shift;
+	writel(val, reg);
+
+	s3c64xx_irq_set_function(d, bank, irqd->hwirq);
+
+	return 0;
+}
+
+/*
+ * irq_chip for gpio interrupts.
+ */
+static struct irq_chip s3c64xx_gpio_irq_chip = {
+	.name		= "GPIO",
+	.irq_unmask	= s3c64xx_gpio_irq_unmask,
+	.irq_mask	= s3c64xx_gpio_irq_mask,
+	.irq_ack	= s3c64xx_gpio_irq_ack,
+	.irq_set_type	= s3c64xx_gpio_irq_set_type,
+};
+
+static int s3c64xx_gpio_irq_map(struct irq_domain *h, unsigned int virq,
+					irq_hw_number_t hw)
+{
+	struct samsung_pin_bank *bank = h->host_data;
+
+	if (!(bank->eint_mask & (1 << hw)))
+		return -EINVAL;
+
+	irq_set_chip_and_handler(virq,
+				&s3c64xx_gpio_irq_chip, handle_level_irq);
+	irq_set_chip_data(virq, bank);
+	set_irq_flags(virq, IRQF_VALID);
+
+	return 0;
+}
+
+/*
+ * irq domain callbacks for external gpio interrupt controller.
+ */
+static const struct irq_domain_ops s3c64xx_gpio_irqd_ops = {
+	.map	= s3c64xx_gpio_irq_map,
+	.xlate	= irq_domain_xlate_twocell,
+};
+
+static void s3c64xx_eint_gpio_irq(unsigned int irq, struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_get_chip(irq);
+	struct s3c64xx_eint_gpio_data *data = irq_get_handler_data(irq);
+	struct samsung_pinctrl_drv_data *drvdata = data->drvdata;
+
+	chained_irq_enter(chip, desc);
+
+	do {
+		unsigned int svc;
+		unsigned int group;
+		unsigned int pin;
+		unsigned int virq;
+
+		svc = readl(drvdata->virt_base + SERVICE_REG);
+		group = SVC_GROUP(svc);
+		pin = svc & SVC_NUM_MASK;
+
+		if (!group)
+			break;
+
+		/* Group 1 is used for two pin banks */
+		if (group == 1) {
+			if (pin < 8)
+				group = 0;
+			else
+				pin -= 8;
+		}
+
+		virq = irq_linear_revmap(data->domains[group], pin);
+		/*
+		 * Something must be really wrong if an unmapped EINT
+		 * was unmasked...
+		 */
+		BUG_ON(!virq);
+
+		generic_handle_irq(virq);
+	} while (1);
+
+	chained_irq_exit(chip, desc);
+}
+
+/**
+ * s3c64xx_eint_gpio_init() - setup handling of external gpio interrupts.
+ * @d: driver data of samsung pinctrl driver.
+ */
+static int s3c64xx_eint_gpio_init(struct samsung_pinctrl_drv_data *d)
+{
+	struct s3c64xx_eint_gpio_data *data;
+	struct samsung_pin_bank *bank;
+	struct device *dev = d->dev;
+	unsigned int nr_domains;
+	unsigned int i;
+
+	if (!d->irq) {
+		dev_err(dev, "irq number not available\n");
+		return -EINVAL;
+	}
+
+	nr_domains = 0;
+	bank = d->ctrl->pin_banks;
+	for (i = 0; i < d->ctrl->nr_banks; ++i, ++bank) {
+		unsigned int nr_eints;
+		unsigned int mask;
+
+		if (bank->eint_type != EINT_TYPE_GPIO)
+			continue;
+
+		mask = bank->eint_mask;
+		nr_eints = fls(mask);
+
+		bank->irq_domain = irq_domain_add_linear(bank->of_node,
+					nr_eints, &s3c64xx_gpio_irqd_ops, bank);
+		if (!bank->irq_domain) {
+			dev_err(dev, "gpio irq domain add failed\n");
+			return -ENXIO;
+		}
+
+		++nr_domains;
+	}
+
+	data = devm_kzalloc(dev, sizeof(*data)
+			+ nr_domains * sizeof(*data->domains), GFP_KERNEL);
+	if (!data) {
+		dev_err(dev, "failed to allocate handler data\n");
+		return -ENOMEM;
+	}
+	data->drvdata = d;
+
+	bank = d->ctrl->pin_banks;
+	nr_domains = 0;
+	for (i = 0; i < d->ctrl->nr_banks; ++i, ++bank) {
+		if (bank->eint_type != EINT_TYPE_GPIO)
+			continue;
+
+		data->domains[nr_domains++] = bank->irq_domain;
+	}
+
+	irq_set_chained_handler(d->irq, s3c64xx_eint_gpio_irq);
+	irq_set_handler_data(d->irq, data);
+
+	return 0;
+}
+
+/*
+ * Functions for configuration of EINT0 wake-up interrupts
+ */
+
+static inline void s3c64xx_eint0_irq_set_mask(struct irq_data *irqd, bool mask)
+{
+	struct s3c64xx_eint0_domain_data *ddata =
+					irq_data_get_irq_chip_data(irqd);
+	struct samsung_pinctrl_drv_data *d = ddata->bank->drvdata;
+	u32 val;
+
+	val = readl(d->virt_base + EINT0MASK_REG);
+	if (mask)
+		val |= 1 << ddata->eints[irqd->hwirq];
+	else
+		val &= ~(1 << ddata->eints[irqd->hwirq]);
+	writel(val, d->virt_base + EINT0MASK_REG);
+}
+
+static void s3c64xx_eint0_irq_unmask(struct irq_data *irqd)
+{
+	s3c64xx_eint0_irq_set_mask(irqd, false);
+}
+
+static void s3c64xx_eint0_irq_mask(struct irq_data *irqd)
+{
+	s3c64xx_eint0_irq_set_mask(irqd, true);
+}
+
+static void s3c64xx_eint0_irq_ack(struct irq_data *irqd)
+{
+	struct s3c64xx_eint0_domain_data *ddata =
+					irq_data_get_irq_chip_data(irqd);
+	struct samsung_pinctrl_drv_data *d = ddata->bank->drvdata;
+
+	writel(1 << ddata->eints[irqd->hwirq],
+					d->virt_base + EINT0PEND_REG);
+}
+
+static int s3c64xx_eint0_irq_set_type(struct irq_data *irqd, unsigned int type)
+{
+	struct s3c64xx_eint0_domain_data *ddata =
+					irq_data_get_irq_chip_data(irqd);
+	struct samsung_pin_bank *bank = ddata->bank;
+	struct samsung_pinctrl_drv_data *d = bank->drvdata;
+	void __iomem *reg;
+	int trigger;
+	u8 shift;
+	u32 val;
+
+	trigger = s3c64xx_irq_get_trigger(type);
+	if (trigger < 0) {
+		pr_err("unsupported external interrupt type\n");
+		return -EINVAL;
+	}
+
+	s3c64xx_irq_set_handler(irqd->irq, type);
+
+	/* Set up interrupt trigger */
+	reg = d->virt_base + EINT0CON0_REG;
+	shift = ddata->eints[irqd->hwirq];
+	if (shift >= EINT_MAX_PER_REG) {
+		reg += 4;
+		shift -= EINT_MAX_PER_REG;
+	}
+	shift = EINT_CON_LEN * (shift / 2);
+
+	val = readl(reg);
+	val &= ~(EINT_CON_MASK << shift);
+	val |= trigger << shift;
+	writel(val, reg);
+
+	s3c64xx_irq_set_function(d, bank, irqd->hwirq);
+
+	return 0;
+}
+
+/*
+ * irq_chip for wakeup interrupts
+ */
+static struct irq_chip s3c64xx_eint0_irq_chip = {
+	.name		= "EINT0",
+	.irq_unmask	= s3c64xx_eint0_irq_unmask,
+	.irq_mask	= s3c64xx_eint0_irq_mask,
+	.irq_ack	= s3c64xx_eint0_irq_ack,
+	.irq_set_type	= s3c64xx_eint0_irq_set_type,
+};
+
+static inline void s3c64xx_irq_demux_eint(unsigned int irq,
+					struct irq_desc *desc, u32 range)
+{
+	struct irq_chip *chip = irq_get_chip(irq);
+	struct s3c64xx_eint0_data *data = irq_get_handler_data(irq);
+	struct samsung_pinctrl_drv_data *drvdata = data->drvdata;
+	unsigned int pend, mask;
+
+	chained_irq_enter(chip, desc);
+
+	pend = readl(drvdata->virt_base + EINT0PEND_REG);
+	mask = readl(drvdata->virt_base + EINT0MASK_REG);
+
+	pend = pend & range & ~mask;
+	pend &= range;
+
+	while (pend) {
+		unsigned int virq;
+
+		irq = fls(pend) - 1;
+		pend &= ~(1 << irq);
+
+		virq = irq_linear_revmap(data->domains[irq], data->pins[irq]);
+		/*
+		 * Something must be really wrong if an unmapped EINT
+		 * was unmasked...
+		 */
+		BUG_ON(!virq);
+
+		generic_handle_irq(virq);
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static void s3c64xx_demux_eint0_3(unsigned int irq, struct irq_desc *desc)
+{
+	s3c64xx_irq_demux_eint(irq, desc, 0xf);
+}
+
+static void s3c64xx_demux_eint4_11(unsigned int irq, struct irq_desc *desc)
+{
+	s3c64xx_irq_demux_eint(irq, desc, 0xff0);
+}
+
+static void s3c64xx_demux_eint12_19(unsigned int irq, struct irq_desc *desc)
+{
+	s3c64xx_irq_demux_eint(irq, desc, 0xff000);
+}
+
+static void s3c64xx_demux_eint20_27(unsigned int irq, struct irq_desc *desc)
+{
+	s3c64xx_irq_demux_eint(irq, desc, 0xff00000);
+}
+
+static irq_flow_handler_t s3c64xx_eint0_handlers[NUM_EINT0_IRQ] = {
+	s3c64xx_demux_eint0_3,
+	s3c64xx_demux_eint4_11,
+	s3c64xx_demux_eint12_19,
+	s3c64xx_demux_eint20_27,
+};
+
+static int s3c64xx_eint0_irq_map(struct irq_domain *h, unsigned int virq,
+					irq_hw_number_t hw)
+{
+	struct s3c64xx_eint0_domain_data *ddata = h->host_data;
+	struct samsung_pin_bank *bank = ddata->bank;
+
+	if (!(bank->eint_mask & (1 << hw)))
+		return -EINVAL;
+
+	irq_set_chip_and_handler(virq,
+				&s3c64xx_eint0_irq_chip, handle_level_irq);
+	irq_set_chip_data(virq, ddata);
+	set_irq_flags(virq, IRQF_VALID);
+
+	return 0;
+}
+
+/*
+ * irq domain callbacks for external wakeup interrupt controller.
+ */
+static const struct irq_domain_ops s3c64xx_eint0_irqd_ops = {
+	.map	= s3c64xx_eint0_irq_map,
+	.xlate	= irq_domain_xlate_twocell,
+};
+
+/* list of external wakeup controllers supported */
+static const struct of_device_id s3c64xx_eint0_irq_ids[] = {
+	{ .compatible = "samsung,s3c64xx-wakeup-eint", },
+	{ }
+};
+
+/**
+ * s3c64xx_eint_eint0_init() - setup handling of external wakeup interrupts.
+ * @d: driver data of samsung pinctrl driver.
+ */
+static int s3c64xx_eint_eint0_init(struct samsung_pinctrl_drv_data *d)
+{
+	struct device *dev = d->dev;
+	struct device_node *eint0_np = NULL;
+	struct device_node *np;
+	struct samsung_pin_bank *bank;
+	struct s3c64xx_eint0_data *data;
+	unsigned int i;
+
+	for_each_child_of_node(dev->of_node, np) {
+		if (of_match_node(s3c64xx_eint0_irq_ids, np)) {
+			eint0_np = np;
+			break;
+		}
+	}
+	if (!eint0_np)
+		return -ENODEV;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		dev_err(dev, "could not allocate memory for wkup eint data\n");
+		return -ENOMEM;
+	}
+	data->drvdata = d;
+
+	for (i = 0; i < NUM_EINT0_IRQ; ++i) {
+		unsigned int irq;
+
+		irq = irq_of_parse_and_map(eint0_np, i);
+		if (!irq) {
+			dev_err(dev, "failed to get wakeup EINT IRQ %d\n", i);
+			return -ENXIO;
+		}
+
+		irq_set_chained_handler(irq, s3c64xx_eint0_handlers[i]);
+		irq_set_handler_data(irq, data);
+	}
+
+	bank = d->ctrl->pin_banks;
+	for (i = 0; i < d->ctrl->nr_banks; ++i, ++bank) {
+		struct s3c64xx_eint0_domain_data *ddata;
+		unsigned int nr_eints;
+		unsigned int mask;
+		unsigned int irq;
+		unsigned int pin;
+
+		if (bank->eint_type != EINT_TYPE_WKUP)
+			continue;
+
+		mask = bank->eint_mask;
+		nr_eints = fls(mask);
+
+		ddata = devm_kzalloc(dev,
+				sizeof(*ddata) + nr_eints, GFP_KERNEL);
+		if (!ddata) {
+			dev_err(dev, "failed to allocate domain data\n");
+			return -ENOMEM;
+		}
+		ddata->bank = bank;
+
+		bank->irq_domain = irq_domain_add_linear(bank->of_node,
+				nr_eints, &s3c64xx_eint0_irqd_ops, ddata);
+		if (!bank->irq_domain) {
+			dev_err(dev, "wkup irq domain add failed\n");
+			return -ENXIO;
+		}
+
+		irq = bank->eint_offset;
+		mask = bank->eint_mask;
+		for (pin = 0; mask; ++pin, mask >>= 1) {
+			if (!(mask & 1))
+				continue;
+			data->domains[irq] = bank->irq_domain;
+			data->pins[irq] = pin;
+			ddata->eints[pin] = irq;
+			++irq;
+		}
+	}
+
+	return 0;
+}
+
+/* pin banks of s3c64xx pin-controller 0 */
+static struct samsung_pin_bank s3c64xx_pin_banks0[] = {
+	PIN_BANK_4BIT_EINTG(8, 0x000, "gpa", 0),
+	PIN_BANK_4BIT_EINTG(7, 0x020, "gpb", 8),
+	PIN_BANK_4BIT_EINTG(8, 0x040, "gpc", 16),
+	PIN_BANK_4BIT_EINTG(5, 0x060, "gpd", 32),
+	PIN_BANK_4BIT(5, 0x080, "gpe"),
+	PIN_BANK_2BIT_EINTG(16, 0x0a0, "gpf", 48, 0x3fff),
+	PIN_BANK_4BIT_EINTG(7, 0x0c0, "gpg", 64),
+	PIN_BANK_4BIT2_EINTG(10, 0x0e0, "gph", 80),
+	PIN_BANK_2BIT(16, 0x100, "gpi"),
+	PIN_BANK_2BIT(12, 0x120, "gpj"),
+	PIN_BANK_4BIT2_ALIVE(16, 0x800, "gpk"),
+	PIN_BANK_4BIT2_EINTW(15, 0x810, "gpl", 16, 0x7f00),
+	PIN_BANK_4BIT_EINTW(6, 0x820, "gpm", 23, 0x1f),
+	PIN_BANK_2BIT_EINTW(16, 0x830, "gpn", 0),
+	PIN_BANK_2BIT_EINTG(16, 0x140, "gpo", 96, 0xffff),
+	PIN_BANK_2BIT_EINTG(15, 0x160, "gpp", 112, 0x7fff),
+	PIN_BANK_2BIT_EINTG(9, 0x180, "gpq", 128, 0x1ff),
+};
+
+/*
+ * Samsung pinctrl driver data for S3C64xx SoC. S3C64xx SoC includes
+ * one gpio/pin-mux/pinconfig controller.
+ */
+struct samsung_pin_ctrl s3c64xx_pin_ctrl[] = {
+	{
+		/* pin-controller instance 1 data */
+		.pin_banks	= s3c64xx_pin_banks0,
+		.nr_banks	= ARRAY_SIZE(s3c64xx_pin_banks0),
+		.eint_gpio_init = s3c64xx_eint_gpio_init,
+		.eint_wkup_init = s3c64xx_eint_eint0_init,
+		.label		= "S3C64xx-GPIO",
+	},
+};
diff --git a/drivers/pinctrl/pinctrl-samsung.c b/drivers/pinctrl/pinctrl-samsung.c
index 8b15c6622b33..4f54faf2971f 100644
--- a/drivers/pinctrl/pinctrl-samsung.c
+++ b/drivers/pinctrl/pinctrl-samsung.c
@@ -971,6 +971,10 @@ static const struct of_device_id samsung_pinctrl_dt_match[] = {
 	{ .compatible = "samsung,exynos4x12-pinctrl",
 		.data = (void *)exynos4x12_pin_ctrl },
 #endif
+#ifdef CONFIG_PINCTRL_S3C64XX
+	{ .compatible = "samsung,s3c64xx-pinctrl",
+		.data = s3c64xx_pin_ctrl },
+#endif
 	{},
 };
 MODULE_DEVICE_TABLE(of, samsung_pinctrl_dt_match);
diff --git a/drivers/pinctrl/pinctrl-samsung.h b/drivers/pinctrl/pinctrl-samsung.h
index 9efeee862e0d..45f27b41e30c 100644
--- a/drivers/pinctrl/pinctrl-samsung.h
+++ b/drivers/pinctrl/pinctrl-samsung.h
@@ -117,7 +117,9 @@ struct samsung_pin_bank_type {
  * @pctl_offset: starting offset of the pin-bank registers.
  * @pin_base: starting pin number of the bank.
  * @nr_pins: number of pins included in this bank.
+ * @eint_func: function to set in CON register to configure pin as EINT.
  * @eint_type: type of the external interrupt supported by the bank.
+ * @eint_mask: bit mask of pins which support EINT function.
  * @name: name to be prefixed for each pin in this pin bank.
  * @of_node: OF node of the bank.
  * @drvdata: link to controller driver data
@@ -131,7 +133,9 @@ struct samsung_pin_bank {
 	u32		pctl_offset;
 	u32		pin_base;
 	u8		nr_pins;
+	u8		eint_func;
 	enum eint_type	eint_type;
+	u32		eint_mask;
 	u32		eint_offset;
 	char		*name;
 	struct device_node *of_node;
@@ -240,5 +244,6 @@ struct samsung_pmx_func {
 /* list of all exported SoC specific data */
 extern struct samsung_pin_ctrl exynos4210_pin_ctrl[];
 extern struct samsung_pin_ctrl exynos4x12_pin_ctrl[];
+extern struct samsung_pin_ctrl s3c64xx_pin_ctrl[];
 
 #endif /* __PINCTRL_SAMSUNG_H */