Merge branch 'next/soc-exynos5440' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into next/soc

From Kukjin Kim:
This is adding support for exynos5440, including Quad ARM Cortex-A15
cores and its reference board SSDK5440.

Note, at this moment, just enabled minimal system part for initial kernel
boot and pinctrl driver.

* 'next/soc-exynos5440' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: dts: Add pin controller node for Samsung EXYNOS5440 SoC
  pinctrl: exynos5440: add pinctrl driver for Samsung EXYNOS5440 SoC
  ARM: dts: add initial dts file for EXYNOS5440, SSDK5440
  ARM: EXYNOS: add support for EXYNOS5440 SoC

Add/add conflict in arch/arm/boot/dts/Makefile.

Signed-off-by: Olof Johansson <olof@lixom.net>

3 files changed, 925 insertions, 0 deletions

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index d96caef..dd08b49 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -188,6 +188,11 @@ config PINCTRL_EXYNOS4
 	depends on OF && GPIOLIB
 	select PINCTRL_SAMSUNG
 
+config PINCTRL_EXYNOS5440
+	bool "Samsung EXYNOS5440 SoC pinctrl driver"
+	select PINMUX
+	select PINCONF
+
 config PINCTRL_MVEBU
 	bool
 	depends on ARCH_MVEBU
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index f395ba5..476928b 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_PINCTRL_U300)	+= pinctrl-u300.o
 obj-$(CONFIG_PINCTRL_COH901)	+= pinctrl-coh901.o
 obj-$(CONFIG_PINCTRL_SAMSUNG)	+= pinctrl-samsung.o
 obj-$(CONFIG_PINCTRL_EXYNOS4)	+= pinctrl-exynos.o
+obj-$(CONFIG_PINCTRL_EXYNOS5440)	+= pinctrl-exynos5440.o
 obj-$(CONFIG_PINCTRL_MVEBU)	+= pinctrl-mvebu.o
 obj-$(CONFIG_PINCTRL_DOVE)	+= pinctrl-dove.o
 obj-$(CONFIG_PINCTRL_KIRKWOOD)	+= pinctrl-kirkwood.o
diff --git a/drivers/pinctrl/pinctrl-exynos5440.c b/drivers/pinctrl/pinctrl-exynos5440.c
new file mode 100644
index 0000000..b8635f6
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-exynos5440.c
@@ -0,0 +1,919 @@
+/*
+ * pin-controller/pin-mux/pin-config/gpio-driver for Samsung's EXYNOS5440 SoC.
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/device.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf.h>
+#include "core.h"
+
+/* EXYNOS5440 GPIO and Pinctrl register offsets */
+#define GPIO_MUX		0x00
+#define GPIO_IE			0x04
+#define GPIO_INT		0x08
+#define GPIO_TYPE		0x0C
+#define GPIO_VAL		0x10
+#define GPIO_OE			0x14
+#define GPIO_IN			0x18
+#define GPIO_PE			0x1C
+#define GPIO_PS			0x20
+#define GPIO_SR			0x24
+#define GPIO_DS0		0x28
+#define GPIO_DS1		0x2C
+
+#define EXYNOS5440_MAX_PINS		23
+#define PIN_NAME_LENGTH		10
+
+#define GROUP_SUFFIX		"-grp"
+#define GSUFFIX_LEN		sizeof(GROUP_SUFFIX)
+#define FUNCTION_SUFFIX		"-mux"
+#define FSUFFIX_LEN		sizeof(FUNCTION_SUFFIX)
+
+/*
+ * pin configuration type and its value are packed together into a 16-bits.
+ * The upper 8-bits represent the configuration type and the lower 8-bits
+ * hold the value of the configuration type.
+ */
+#define PINCFG_TYPE_MASK		0xFF
+#define PINCFG_VALUE_SHIFT		8
+#define PINCFG_VALUE_MASK		(0xFF << PINCFG_VALUE_SHIFT)
+#define PINCFG_PACK(type, value)	(((value) << PINCFG_VALUE_SHIFT) | type)
+#define PINCFG_UNPACK_TYPE(cfg)		((cfg) & PINCFG_TYPE_MASK)
+#define PINCFG_UNPACK_VALUE(cfg)	(((cfg) & PINCFG_VALUE_MASK) >> \
+						PINCFG_VALUE_SHIFT)
+
+/**
+ * enum pincfg_type - possible pin configuration types supported.
+ * @PINCFG_TYPE_PUD: Pull up/down configuration.
+ * @PINCFG_TYPE_DRV: Drive strength configuration.
+ * @PINCFG_TYPE_SKEW_RATE: Skew rate configuration.
+ * @PINCFG_TYPE_INPUT_TYPE: Pin input type configuration.
+ */
+enum pincfg_type {
+	PINCFG_TYPE_PUD,
+	PINCFG_TYPE_DRV,
+	PINCFG_TYPE_SKEW_RATE,
+	PINCFG_TYPE_INPUT_TYPE
+};
+
+/**
+ * struct exynos5440_pin_group: represent group of pins for pincfg setting.
+ * @name: name of the pin group, used to lookup the group.
+ * @pins: the pins included in this group.
+ * @num_pins: number of pins included in this group.
+ */
+struct exynos5440_pin_group {
+	const char		*name;
+	const unsigned int	*pins;
+	u8			num_pins;
+};
+
+/**
+ * struct exynos5440_pmx_func: represent a pin function.
+ * @name: name of the pin function, used to lookup the function.
+ * @groups: one or more names of pin groups that provide this function.
+ * @num_groups: number of groups included in @groups.
+ * @function: the function number to be programmed when selected.
+ */
+struct exynos5440_pmx_func {
+	const char		*name;
+	const char		**groups;
+	u8			num_groups;
+	unsigned long		function;
+};
+
+/**
+ * struct exynos5440_pinctrl_priv_data: driver's private runtime data.
+ * @reg_base: ioremapped based address of the register space.
+ * @gc: gpio chip registered with gpiolib.
+ * @pin_groups: list of pin groups parsed from device tree.
+ * @nr_groups: number of pin groups available.
+ * @pmx_functions: list of pin functions parsed from device tree.
+ * @nr_functions: number of pin functions available.
+ */
+struct exynos5440_pinctrl_priv_data {
+	void __iomem			*reg_base;
+	struct gpio_chip		*gc;
+
+	const struct exynos5440_pin_group	*pin_groups;
+	unsigned int			nr_groups;
+	const struct exynos5440_pmx_func	*pmx_functions;
+	unsigned int			nr_functions;
+};
+
+/* list of all possible config options supported */
+struct pin_config {
+	char		*prop_cfg;
+	unsigned int	cfg_type;
+} pcfgs[] = {
+	{ "samsung,exynos5440-pin-pud", PINCFG_TYPE_PUD },
+	{ "samsung,exynos5440-pin-drv", PINCFG_TYPE_DRV },
+	{ "samsung,exynos5440-pin-skew-rate", PINCFG_TYPE_SKEW_RATE },
+	{ "samsung,exynos5440-pin-input-type", PINCFG_TYPE_INPUT_TYPE },
+};
+
+/* check if the selector is a valid pin group selector */
+static int exynos5440_get_group_count(struct pinctrl_dev *pctldev)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	return priv->nr_groups;
+}
+
+/* return the name of the group selected by the group selector */
+static const char *exynos5440_get_group_name(struct pinctrl_dev *pctldev,
+						unsigned selector)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	return priv->pin_groups[selector].name;
+}
+
+/* return the pin numbers associated with the specified group */
+static int exynos5440_get_group_pins(struct pinctrl_dev *pctldev,
+		unsigned selector, const unsigned **pins, unsigned *num_pins)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	*pins = priv->pin_groups[selector].pins;
+	*num_pins = priv->pin_groups[selector].num_pins;
+	return 0;
+}
+
+/* create pinctrl_map entries by parsing device tree nodes */
+static int exynos5440_dt_node_to_map(struct pinctrl_dev *pctldev,
+			struct device_node *np, struct pinctrl_map **maps,
+			unsigned *nmaps)
+{
+	struct device *dev = pctldev->dev;
+	struct pinctrl_map *map;
+	unsigned long *cfg = NULL;
+	char *gname, *fname;
+	int cfg_cnt = 0, map_cnt = 0, idx = 0;
+
+	/* count the number of config options specfied in the node */
+	for (idx = 0; idx < ARRAY_SIZE(pcfgs); idx++)
+		if (of_find_property(np, pcfgs[idx].prop_cfg, NULL))
+			cfg_cnt++;
+
+	/*
+	 * Find out the number of map entries to create. All the config options
+	 * can be accomadated into a single config map entry.
+	 */
+	if (cfg_cnt)
+		map_cnt = 1;
+	if (of_find_property(np, "samsung,exynos5440-pin-function", NULL))
+		map_cnt++;
+	if (!map_cnt) {
+		dev_err(dev, "node %s does not have either config or function "
+				"configurations\n", np->name);
+		return -EINVAL;
+	}
+
+	/* Allocate memory for pin-map entries */
+	map = kzalloc(sizeof(*map) * map_cnt, GFP_KERNEL);
+	if (!map) {
+		dev_err(dev, "could not alloc memory for pin-maps\n");
+		return -ENOMEM;
+	}
+	*nmaps = 0;
+
+	/*
+	 * Allocate memory for pin group name. The pin group name is derived
+	 * from the node name from which these map entries are be created.
+	 */
+	gname = kzalloc(strlen(np->name) + GSUFFIX_LEN, GFP_KERNEL);
+	if (!gname) {
+		dev_err(dev, "failed to alloc memory for group name\n");
+		goto free_map;
+	}
+	sprintf(gname, "%s%s", np->name, GROUP_SUFFIX);
+
+	/*
+	 * don't have config options? then skip over to creating function
+	 * map entries.
+	 */
+	if (!cfg_cnt)
+		goto skip_cfgs;
+
+	/* Allocate memory for config entries */
+	cfg = kzalloc(sizeof(*cfg) * cfg_cnt, GFP_KERNEL);
+	if (!cfg) {
+		dev_err(dev, "failed to alloc memory for configs\n");
+		goto free_gname;
+	}
+
+	/* Prepare a list of config settings */
+	for (idx = 0, cfg_cnt = 0; idx < ARRAY_SIZE(pcfgs); idx++) {
+		u32 value;
+		if (!of_property_read_u32(np, pcfgs[idx].prop_cfg, &value))
+			cfg[cfg_cnt++] =
+				PINCFG_PACK(pcfgs[idx].cfg_type, value);
+	}
+
+	/* create the config map entry */
+	map[*nmaps].data.configs.group_or_pin = gname;
+	map[*nmaps].data.configs.configs = cfg;
+	map[*nmaps].data.configs.num_configs = cfg_cnt;
+	map[*nmaps].type = PIN_MAP_TYPE_CONFIGS_GROUP;
+	*nmaps += 1;
+
+skip_cfgs:
+	/* create the function map entry */
+	if (of_find_property(np, "samsung,exynos5440-pin-function", NULL)) {
+		fname = kzalloc(strlen(np->name) + FSUFFIX_LEN,	GFP_KERNEL);
+		if (!fname) {
+			dev_err(dev, "failed to alloc memory for func name\n");
+			goto free_cfg;
+		}
+		sprintf(fname, "%s%s", np->name, FUNCTION_SUFFIX);
+
+		map[*nmaps].data.mux.group = gname;
+		map[*nmaps].data.mux.function = fname;
+		map[*nmaps].type = PIN_MAP_TYPE_MUX_GROUP;
+		*nmaps += 1;
+	}
+
+	*maps = map;
+	return 0;
+
+free_cfg:
+	kfree(cfg);
+free_gname:
+	kfree(gname);
+free_map:
+	kfree(map);
+	return -ENOMEM;
+}
+
+/* free the memory allocated to hold the pin-map table */
+static void exynos5440_dt_free_map(struct pinctrl_dev *pctldev,
+			     struct pinctrl_map *map, unsigned num_maps)
+{
+	int idx;
+
+	for (idx = 0; idx < num_maps; idx++) {
+		if (map[idx].type == PIN_MAP_TYPE_MUX_GROUP) {
+			kfree(map[idx].data.mux.function);
+			if (!idx)
+				kfree(map[idx].data.mux.group);
+		} else if (map->type == PIN_MAP_TYPE_CONFIGS_GROUP) {
+			kfree(map[idx].data.configs.configs);
+			if (!idx)
+				kfree(map[idx].data.configs.group_or_pin);
+		}
+	};
+
+	kfree(map);
+}
+
+/* list of pinctrl callbacks for the pinctrl core */
+static struct pinctrl_ops exynos5440_pctrl_ops = {
+	.get_groups_count	= exynos5440_get_group_count,
+	.get_group_name		= exynos5440_get_group_name,
+	.get_group_pins		= exynos5440_get_group_pins,
+	.dt_node_to_map		= exynos5440_dt_node_to_map,
+	.dt_free_map		= exynos5440_dt_free_map,
+};
+
+/* check if the selector is a valid pin function selector */
+static int exynos5440_get_functions_count(struct pinctrl_dev *pctldev)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	return priv->nr_functions;
+}
+
+/* return the name of the pin function specified */
+static const char *exynos5440_pinmux_get_fname(struct pinctrl_dev *pctldev,
+						unsigned selector)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	return priv->pmx_functions[selector].name;
+}
+
+/* return the groups associated for the specified function selector */
+static int exynos5440_pinmux_get_groups(struct pinctrl_dev *pctldev,
+		unsigned selector, const char * const **groups,
+		unsigned * const num_groups)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	*groups = priv->pmx_functions[selector].groups;
+	*num_groups = priv->pmx_functions[selector].num_groups;
+	return 0;
+}
+
+/* enable or disable a pinmux function */
+static void exynos5440_pinmux_setup(struct pinctrl_dev *pctldev, unsigned selector,
+					unsigned group, bool enable)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+	void __iomem *base;
+	u32 function;
+	u32 data;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	base = priv->reg_base;
+	function = priv->pmx_functions[selector].function;
+
+	data = readl(base + GPIO_MUX);
+	if (enable)
+		data |= (1 << function);
+	else
+		data &= ~(1 << function);
+	writel(data, base + GPIO_MUX);
+}
+
+/* enable a specified pinmux by writing to registers */
+static int exynos5440_pinmux_enable(struct pinctrl_dev *pctldev, unsigned selector,
+					unsigned group)
+{
+	exynos5440_pinmux_setup(pctldev, selector, group, true);
+	return 0;
+}
+
+/* disable a specified pinmux by writing to registers */
+static void exynos5440_pinmux_disable(struct pinctrl_dev *pctldev,
+					unsigned selector, unsigned group)
+{
+	exynos5440_pinmux_setup(pctldev, selector, group, false);
+}
+
+/*
+ * The calls to gpio_direction_output() and gpio_direction_input()
+ * leads to this function call (via the pinctrl_gpio_direction_{input|output}()
+ * function called from the gpiolib interface).
+ */
+static int exynos5440_pinmux_gpio_set_direction(struct pinctrl_dev *pctldev,
+		struct pinctrl_gpio_range *range, unsigned offset, bool input)
+{
+	return 0;
+}
+
+/* list of pinmux callbacks for the pinmux vertical in pinctrl core */
+static struct pinmux_ops exynos5440_pinmux_ops = {
+	.get_functions_count	= exynos5440_get_functions_count,
+	.get_function_name	= exynos5440_pinmux_get_fname,
+	.get_function_groups	= exynos5440_pinmux_get_groups,
+	.enable			= exynos5440_pinmux_enable,
+	.disable		= exynos5440_pinmux_disable,
+	.gpio_set_direction	= exynos5440_pinmux_gpio_set_direction,
+};
+
+/* set the pin config settings for a specified pin */
+static int exynos5440_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
+				unsigned long config)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+	void __iomem *base;
+	enum pincfg_type cfg_type = PINCFG_UNPACK_TYPE(config);
+	u32 cfg_value = PINCFG_UNPACK_VALUE(config);
+	u32 data;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	base = priv->reg_base;
+
+	switch (cfg_type) {
+	case PINCFG_TYPE_PUD:
+		/* first set pull enable/disable bit */
+		data = readl(base + GPIO_PE);
+		data &= ~(1 << pin);
+		if (cfg_value)
+			data |= (1 << pin);
+		writel(data, base + GPIO_PE);
+
+		/* then set pull up/down bit */
+		data = readl(base + GPIO_PS);
+		data &= ~(1 << pin);
+		if (cfg_value == 2)
+			data |= (1 << pin);
+		writel(data, base + GPIO_PS);
+		break;
+
+	case PINCFG_TYPE_DRV:
+		/* set the first bit of the drive strength */
+		data = readl(base + GPIO_DS0);
+		data &= ~(1 << pin);
+		data |= ((cfg_value & 1) << pin);
+		writel(data, base + GPIO_DS0);
+		cfg_value >>= 1;
+
+		/* set the second bit of the driver strength */
+		data = readl(base + GPIO_DS1);
+		data &= ~(1 << pin);
+		data |= ((cfg_value & 1) << pin);
+		writel(data, base + GPIO_DS1);
+		break;
+	case PINCFG_TYPE_SKEW_RATE:
+		data = readl(base + GPIO_SR);
+		data &= ~(1 << pin);
+		data |= ((cfg_value & 1) << pin);
+		writel(data, base + GPIO_SR);
+		break;
+	case PINCFG_TYPE_INPUT_TYPE:
+		data = readl(base + GPIO_TYPE);
+		data &= ~(1 << pin);
+		data |= ((cfg_value & 1) << pin);
+		writel(data, base + GPIO_TYPE);
+		break;
+	default:
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* get the pin config settings for a specified pin */
+static int exynos5440_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
+					unsigned long *config)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+	void __iomem *base;
+	enum pincfg_type cfg_type = PINCFG_UNPACK_TYPE(*config);
+	u32 data;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	base = priv->reg_base;
+
+	switch (cfg_type) {
+	case PINCFG_TYPE_PUD:
+		data = readl(base + GPIO_PE);
+		data = (data >> pin) & 1;
+		if (!data)
+			*config = 0;
+		else
+			*config = ((readl(base + GPIO_PS) >> pin) & 1) + 1;
+		break;
+	case PINCFG_TYPE_DRV:
+		data = readl(base + GPIO_DS0);
+		data = (data >> pin) & 1;
+		*config = data;
+		data = readl(base + GPIO_DS1);
+		data = (data >> pin) & 1;
+		*config |= (data << 1);
+		break;
+	case PINCFG_TYPE_SKEW_RATE:
+		data = readl(base + GPIO_SR);
+		*config = (data >> pin) & 1;
+		break;
+	case PINCFG_TYPE_INPUT_TYPE:
+		data = readl(base + GPIO_TYPE);
+		*config = (data >> pin) & 1;
+		break;
+	default:
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* set the pin config settings for a specified pin group */
+static int exynos5440_pinconf_group_set(struct pinctrl_dev *pctldev,
+			unsigned group, unsigned long config)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+	const unsigned int *pins;
+	unsigned int cnt;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	pins = priv->pin_groups[group].pins;
+
+	for (cnt = 0; cnt < priv->pin_groups[group].num_pins; cnt++)
+		exynos5440_pinconf_set(pctldev, pins[cnt], config);
+
+	return 0;
+}
+
+/* get the pin config settings for a specified pin group */
+static int exynos5440_pinconf_group_get(struct pinctrl_dev *pctldev,
+				unsigned int group, unsigned long *config)
+{
+	struct exynos5440_pinctrl_priv_data *priv;
+	const unsigned int *pins;
+
+	priv = pinctrl_dev_get_drvdata(pctldev);
+	pins = priv->pin_groups[group].pins;
+	exynos5440_pinconf_get(pctldev, pins[0], config);
+	return 0;
+}
+
+/* list of pinconfig callbacks for pinconfig vertical in the pinctrl code */
+static struct pinconf_ops exynos5440_pinconf_ops = {
+	.pin_config_get		= exynos5440_pinconf_get,
+	.pin_config_set		= exynos5440_pinconf_set,
+	.pin_config_group_get	= exynos5440_pinconf_group_get,
+	.pin_config_group_set	= exynos5440_pinconf_group_set,
+};
+
+/* gpiolib gpio_set callback function */
+static void exynos5440_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
+{
+	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
+	void __iomem *base = priv->reg_base;
+	u32 data;
+
+	data = readl(base + GPIO_VAL);
+	data &= ~(1 << offset);
+	if (value)
+		data |= 1 << offset;
+	writel(data, base + GPIO_VAL);
+}
+
+/* gpiolib gpio_get callback function */
+static int exynos5440_gpio_get(struct gpio_chip *gc, unsigned offset)
+{
+	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
+	void __iomem *base = priv->reg_base;
+	u32 data;
+
+	data = readl(base + GPIO_IN);
+	data >>= offset;
+	data &= 1;
+	return data;
+}
+
+/* gpiolib gpio_direction_input callback function */
+static int exynos5440_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
+	void __iomem *base = priv->reg_base;
+	u32 data;
+
+	/* first disable the data output enable on this pin */
+	data = readl(base + GPIO_OE);
+	data &= ~(1 << offset);
+	writel(data, base + GPIO_OE);
+
+	/* now enable input on this pin */
+	data =  readl(base + GPIO_IE);
+	data |= 1 << offset;
+	writel(data, base + GPIO_IE);
+	return 0;
+}
+
+/* gpiolib gpio_direction_output callback function */
+static int exynos5440_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
+							int value)
+{
+	struct exynos5440_pinctrl_priv_data *priv = dev_get_drvdata(gc->dev);
+	void __iomem *base = priv->reg_base;
+	u32 data;
+
+	exynos5440_gpio_set(gc, offset, value);
+
+	/* first disable the data input enable on this pin */
+	data = readl(base + GPIO_IE);
+	data &= ~(1 << offset);
+	writel(data, base + GPIO_IE);
+
+	/* now enable output on this pin */
+	data =  readl(base + GPIO_OE);
+	data |= 1 << offset;
+	writel(data, base + GPIO_OE);
+	return 0;
+}
+
+/* parse the pin numbers listed in the 'samsung,exynos5440-pins' property */
+static int __init exynos5440_pinctrl_parse_dt_pins(struct platform_device *pdev,
+			struct device_node *cfg_np, unsigned int **pin_list,
+			unsigned int *npins)
+{
+	struct device *dev = &pdev->dev;
+	struct property *prop;
+
+	prop = of_find_property(cfg_np, "samsung,exynos5440-pins", NULL);
+	if (!prop)
+		return -ENOENT;
+
+	*npins = prop->length / sizeof(unsigned long);
+	if (!*npins) {
+		dev_err(dev, "invalid pin list in %s node", cfg_np->name);
+		return -EINVAL;
+	}
+
+	*pin_list = devm_kzalloc(dev, *npins * sizeof(**pin_list), GFP_KERNEL);
+	if (!*pin_list) {
+		dev_err(dev, "failed to allocate memory for pin list\n");
+		return -ENOMEM;
+	}
+
+	return of_property_read_u32_array(cfg_np, "samsung,exynos5440-pins",
+			*pin_list, *npins);
+}
+
+/*
+ * Parse the information about all the available pin groups and pin functions
+ * from device node of the pin-controller.
+ */
+static int __init exynos5440_pinctrl_parse_dt(struct platform_device *pdev,
+				struct exynos5440_pinctrl_priv_data *priv)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *dev_np = dev->of_node;
+	struct device_node *cfg_np;
+	struct exynos5440_pin_group *groups, *grp;
+	struct exynos5440_pmx_func *functions, *func;
+	unsigned *pin_list;
+	unsigned int npins, grp_cnt, func_idx = 0;
+	char *gname, *fname;
+	int ret;
+
+	grp_cnt = of_get_child_count(dev_np);
+	if (!grp_cnt)
+		return -EINVAL;
+
+	groups = devm_kzalloc(dev, grp_cnt * sizeof(*groups), GFP_KERNEL);
+	if (!groups) {
+		dev_err(dev, "failed allocate memory for ping group list\n");
+		return -EINVAL;
+	}
+	grp = groups;
+
+	functions = devm_kzalloc(dev, grp_cnt * sizeof(*functions), GFP_KERNEL);
+	if (!functions) {
+		dev_err(dev, "failed to allocate memory for function list\n");
+		return -EINVAL;
+	}
+	func = functions;
+
+	/*
+	 * Iterate over all the child nodes of the pin controller node
+	 * and create pin groups and pin function lists.
+	 */
+	for_each_child_of_node(dev_np, cfg_np) {
+		u32 function;
+
+		ret = exynos5440_pinctrl_parse_dt_pins(pdev, cfg_np,
+					&pin_list, &npins);
+		if (ret)
+			return ret;
+
+		/* derive pin group name from the node name */
+		gname = devm_kzalloc(dev, strlen(cfg_np->name) + GSUFFIX_LEN,
+					GFP_KERNEL);
+		if (!gname) {
+			dev_err(dev, "failed to alloc memory for group name\n");
+			return -ENOMEM;
+		}
+		sprintf(gname, "%s%s", cfg_np->name, GROUP_SUFFIX);
+
+		grp->name = gname;
+		grp->pins = pin_list;
+		grp->num_pins = npins;
+		grp++;
+
+		ret = of_property_read_u32(cfg_np, "samsung,exynos5440-pin-function",
+						&function);
+		if (ret)
+			continue;
+
+		/* derive function name from the node name */
+		fname = devm_kzalloc(dev, strlen(cfg_np->name) + FSUFFIX_LEN,
+					GFP_KERNEL);
+		if (!fname) {
+			dev_err(dev, "failed to alloc memory for func name\n");
+			return -ENOMEM;
+		}
+		sprintf(fname, "%s%s", cfg_np->name, FUNCTION_SUFFIX);
+
+		func->name = fname;
+		func->groups = devm_kzalloc(dev, sizeof(char *), GFP_KERNEL);
+		if (!func->groups) {
+			dev_err(dev, "failed to alloc memory for group list "
+					"in pin function");
+			return -ENOMEM;
+		}
+		func->groups[0] = gname;
+		func->num_groups = 1;
+		func->function = function;
+		func++;
+		func_idx++;
+	}
+
+	priv->pin_groups = groups;
+	priv->nr_groups = grp_cnt;
+	priv->pmx_functions = functions;
+	priv->nr_functions = func_idx;
+	return 0;
+}
+
+/* register the pinctrl interface with the pinctrl subsystem */
+static int __init exynos5440_pinctrl_register(struct platform_device *pdev,
+				struct exynos5440_pinctrl_priv_data *priv)
+{
+	struct device *dev = &pdev->dev;
+	struct pinctrl_desc *ctrldesc;
+	struct pinctrl_dev *pctl_dev;
+	struct pinctrl_pin_desc *pindesc, *pdesc;
+	struct pinctrl_gpio_range grange;
+	char *pin_names;
+	int pin, ret;
+
+	ctrldesc = devm_kzalloc(dev, sizeof(*ctrldesc), GFP_KERNEL);
+	if (!ctrldesc) {
+		dev_err(dev, "could not allocate memory for pinctrl desc\n");
+		return -ENOMEM;
+	}
+
+	ctrldesc->name = "exynos5440-pinctrl";
+	ctrldesc->owner = THIS_MODULE;
+	ctrldesc->pctlops = &exynos5440_pctrl_ops;
+	ctrldesc->pmxops = &exynos5440_pinmux_ops;
+	ctrldesc->confops = &exynos5440_pinconf_ops;
+
+	pindesc = devm_kzalloc(&pdev->dev, sizeof(*pindesc) *
+				EXYNOS5440_MAX_PINS, GFP_KERNEL);
+	if (!pindesc) {
+		dev_err(&pdev->dev, "mem alloc for pin descriptors failed\n");
+		return -ENOMEM;
+	}
+	ctrldesc->pins = pindesc;
+	ctrldesc->npins = EXYNOS5440_MAX_PINS;
+
+	/* dynamically populate the pin number and pin name for pindesc */
+	for (pin = 0, pdesc = pindesc; pin < ctrldesc->npins; pin++, pdesc++)
+		pdesc->number = pin;
+
+	/*
+	 * allocate space for storing the dynamically generated names for all
+	 * the pins which belong to this pin-controller.
+	 */
+	pin_names = devm_kzalloc(&pdev->dev, sizeof(char) * PIN_NAME_LENGTH *
+					ctrldesc->npins, GFP_KERNEL);
+	if (!pin_names) {
+		dev_err(&pdev->dev, "mem alloc for pin names failed\n");
+		return -ENOMEM;
+	}
+
+	/* for each pin, set the name of the pin */
+	for (pin = 0; pin < ctrldesc->npins; pin++) {
+		sprintf(pin_names, "gpio%02d", pin);
+		pdesc = pindesc + pin;
+		pdesc->name = pin_names;
+		pin_names += PIN_NAME_LENGTH;
+	}
+
+	ret = exynos5440_pinctrl_parse_dt(pdev, priv);
+	if (ret)
+		return ret;
+
+	pctl_dev = pinctrl_register(ctrldesc, &pdev->dev, priv);
+	if (!pctl_dev) {
+		dev_err(&pdev->dev, "could not register pinctrl driver\n");
+		return -EINVAL;
+	}
+
+	grange.name = "exynos5440-pctrl-gpio-range";
+	grange.id = 0;
+	grange.base = 0;
+	grange.npins = EXYNOS5440_MAX_PINS;
+	grange.gc = priv->gc;
+	pinctrl_add_gpio_range(pctl_dev, &grange);
+	return 0;
+}
+
+/* register the gpiolib interface with the gpiolib subsystem */
+static int __init exynos5440_gpiolib_register(struct platform_device *pdev,
+				struct exynos5440_pinctrl_priv_data *priv)
+{
+	struct gpio_chip *gc;
+	int ret;
+
+	gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
+	if (!gc) {
+		dev_err(&pdev->dev, "mem alloc for gpio_chip failed\n");
+		return -ENOMEM;
+	}
+
+	priv->gc = gc;
+	gc->base = 0;
+	gc->ngpio = EXYNOS5440_MAX_PINS;
+	gc->dev = &pdev->dev;
+	gc->set = exynos5440_gpio_set;
+	gc->get = exynos5440_gpio_get;
+	gc->direction_input = exynos5440_gpio_direction_input;
+	gc->direction_output = exynos5440_gpio_direction_output;
+	gc->label = "gpiolib-exynos5440";
+	gc->owner = THIS_MODULE;
+	ret = gpiochip_add(gc);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register gpio_chip %s, error "
+					"code: %d\n", gc->label, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+/* unregister the gpiolib interface with the gpiolib subsystem */
+static int __init exynos5440_gpiolib_unregister(struct platform_device *pdev,
+				struct exynos5440_pinctrl_priv_data *priv)
+{
+	int ret = gpiochip_remove(priv->gc);
+	if (ret) {
+		dev_err(&pdev->dev, "gpio chip remove failed\n");
+		return ret;
+	}
+	return 0;
+}
+
+static int __devinit exynos5440_pinctrl_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct exynos5440_pinctrl_priv_data *priv;
+	struct resource *res;
+	int ret;
+
+	if (!dev->of_node) {
+		dev_err(dev, "device tree node not found\n");
+		return -ENODEV;
+	}
+
+	priv = devm_kzalloc(dev, sizeof(priv), GFP_KERNEL);
+	if (!priv) {
+		dev_err(dev, "could not allocate memory for private data\n");
+		return -ENOMEM;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "cannot find IO resource\n");
+		return -ENOENT;
+	}
+
+	priv->reg_base = devm_request_and_ioremap(&pdev->dev, res);
+	if (!priv->reg_base) {
+		dev_err(dev, "ioremap failed\n");
+		return -ENODEV;
+	}
+
+	ret = exynos5440_gpiolib_register(pdev, priv);
+	if (ret)
+		return ret;
+
+	ret = exynos5440_pinctrl_register(pdev, priv);
+	if (ret) {
+		exynos5440_gpiolib_unregister(pdev, priv);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, priv);
+	dev_info(dev, "EXYNOS5440 pinctrl driver registered\n");
+	return 0;
+}
+
+static const struct of_device_id exynos5440_pinctrl_dt_match[] = {
+	{ .compatible = "samsung,exynos5440-pinctrl" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, exynos5440_pinctrl_dt_match);
+
+static struct platform_driver exynos5440_pinctrl_driver = {
+	.probe		= exynos5440_pinctrl_probe,
+	.driver = {
+		.name	= "exynos5440-pinctrl",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(exynos5440_pinctrl_dt_match),
+	},
+};
+
+static int __init exynos5440_pinctrl_drv_register(void)
+{
+	return platform_driver_register(&exynos5440_pinctrl_driver);
+}
+postcore_initcall(exynos5440_pinctrl_drv_register);
+
+static void __exit exynos5440_pinctrl_drv_unregister(void)
+{
+	platform_driver_unregister(&exynos5440_pinctrl_driver);
+}
+module_exit(exynos5440_pinctrl_drv_unregister);
+
+MODULE_AUTHOR("Thomas Abraham <thomas.ab@samsung.com>");
+MODULE_DESCRIPTION("Samsung EXYNOS5440 SoC pinctrl driver");
+MODULE_LICENSE("GPL v2");