regulator: Add S5M8767A regulator driver

S5M8767A is a cost-effective PMIC which is designed for mobile applications.
It includes high efficient 9 Buck converters, 28 LDOs.
Especially, S5M8767A is optimized for Multi-core SOCs.
And during DVFS operation, S5M8767A output stable voltage.
This patch implement regulator driver for S5M8767A.
Signed-off-by: Sangbeom Kim <sbkim73@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/s5m8767.c

+/*
+ * s5m8767.c
+ *
+ * Copyright (c) 2011 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/bug.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/mfd/s5m87xx/s5m-core.h>
+#include <linux/mfd/s5m87xx/s5m-pmic.h>
+
+struct s5m8767_info {
+	struct device *dev;
+	struct s5m87xx_dev *iodev;
+	int num_regulators;
+	struct regulator_dev **rdev;
+
+	int ramp_delay;
+	bool buck2_ramp;
+	bool buck3_ramp;
+	bool buck4_ramp;
+
+	bool buck2_gpiodvs;
+	bool buck3_gpiodvs;
+	bool buck4_gpiodvs;
+	u8 buck2_vol[8];
+	u8 buck3_vol[8];
+	u8 buck4_vol[8];
+	int buck_gpios[3];
+	int buck_gpioindex;
+};
+
+struct s5m_voltage_desc {
+	int max;
+	int min;
+	int step;
+};
+
+static const struct s5m_voltage_desc buck_voltage_val1 = {
+	.max = 2225000,
+	.min =  650000,
+	.step =   6250,
+};
+
+static const struct s5m_voltage_desc buck_voltage_val2 = {
+	.max = 1600000,
+	.min =  600000,
+	.step =   6250,
+};
+
+static const struct s5m_voltage_desc buck_voltage_val3 = {
+	.max = 3000000,
+	.min =  750000,
+	.step =  12500,
+};
+
+static const struct s5m_voltage_desc ldo_voltage_val1 = {
+	.max = 3950000,
+	.min =  800000,
+	.step =  50000,
+};
+
+static const struct s5m_voltage_desc ldo_voltage_val2 = {
+	.max = 2375000,
+	.min =  800000,
+	.step =  25000,
+};
+
+static const struct s5m_voltage_desc *reg_voltage_map[] = {
+	[S5M8767_LDO1] = &ldo_voltage_val2,
+	[S5M8767_LDO2] = &ldo_voltage_val2,
+	[S5M8767_LDO3] = &ldo_voltage_val1,
+	[S5M8767_LDO4] = &ldo_voltage_val1,
+	[S5M8767_LDO5] = &ldo_voltage_val1,
+	[S5M8767_LDO6] = &ldo_voltage_val2,
+	[S5M8767_LDO7] = &ldo_voltage_val2,
+	[S5M8767_LDO8] = &ldo_voltage_val2,
+	[S5M8767_LDO9] = &ldo_voltage_val1,
+	[S5M8767_LDO10] = &ldo_voltage_val1,
+	[S5M8767_LDO11] = &ldo_voltage_val1,
+	[S5M8767_LDO12] = &ldo_voltage_val1,
+	[S5M8767_LDO13] = &ldo_voltage_val1,
+	[S5M8767_LDO14] = &ldo_voltage_val1,
+	[S5M8767_LDO15] = &ldo_voltage_val2,
+	[S5M8767_LDO16] = &ldo_voltage_val1,
+	[S5M8767_LDO17] = &ldo_voltage_val1,
+	[S5M8767_LDO18] = &ldo_voltage_val1,
+	[S5M8767_LDO19] = &ldo_voltage_val1,
+	[S5M8767_LDO20] = &ldo_voltage_val1,
+	[S5M8767_LDO21] = &ldo_voltage_val1,
+	[S5M8767_LDO22] = &ldo_voltage_val1,
+	[S5M8767_LDO23] = &ldo_voltage_val1,
+	[S5M8767_LDO24] = &ldo_voltage_val1,
+	[S5M8767_LDO25] = &ldo_voltage_val1,
+	[S5M8767_LDO26] = &ldo_voltage_val1,
+	[S5M8767_LDO27] = &ldo_voltage_val1,
+	[S5M8767_LDO28] = &ldo_voltage_val1,
+	[S5M8767_BUCK1] = &buck_voltage_val1,
+	[S5M8767_BUCK2] = &buck_voltage_val2,
+	[S5M8767_BUCK3] = &buck_voltage_val2,
+	[S5M8767_BUCK4] = &buck_voltage_val2,
+	[S5M8767_BUCK5] = &buck_voltage_val1,
+	[S5M8767_BUCK6] = &buck_voltage_val1,
+	[S5M8767_BUCK7] = NULL,
+	[S5M8767_BUCK8] = NULL,
+	[S5M8767_BUCK9] = &buck_voltage_val3,
+};
+
+static inline int s5m8767_get_reg_id(struct regulator_dev *rdev)
+{
+	return rdev_get_id(rdev);
+}
+
+static int s5m8767_list_voltage(struct regulator_dev *rdev,
+				unsigned int selector)
+{
+	const struct s5m_voltage_desc *desc;
+	int reg_id = s5m8767_get_reg_id(rdev);
+	int val;
+
+	if (reg_id >= ARRAY_SIZE(reg_voltage_map) || reg_id < 0)
+		return -EINVAL;
+
+	desc = reg_voltage_map[reg_id];
+	if (desc == NULL)
+		return -EINVAL;
+
+	val = desc->min + desc->step * selector;
+	if (val > desc->max)
+		return -EINVAL;
+
+	return val;
+}
+
+static int s5m8767_get_register(struct regulator_dev *rdev, int *reg)
+{
+	int reg_id = s5m8767_get_reg_id(rdev);
+
+	switch (reg_id) {
+	case S5M8767_LDO1 ... S5M8767_LDO2:
+		*reg = S5M8767_REG_LDO1CTRL + (reg_id - S5M8767_LDO1);
+		break;
+	case S5M8767_LDO3 ... S5M8767_LDO28:
+		*reg = S5M8767_REG_LDO3CTRL + (reg_id - S5M8767_LDO3);
+		break;
+	case S5M8767_BUCK1:
+		*reg = S5M8767_REG_BUCK1CTRL1;
+		break;
+	case S5M8767_BUCK2 ... S5M8767_BUCK4:
+		*reg = S5M8767_REG_BUCK2CTRL + (reg_id - S5M8767_BUCK2) * 9;
+		break;
+	case S5M8767_BUCK5:
+		*reg = S5M8767_REG_BUCK5CTRL1;
+		break;
+	case S5M8767_BUCK6 ... S5M8767_BUCK9:
+		*reg = S5M8767_REG_BUCK6CTRL1 + (reg_id - S5M8767_BUCK6) * 2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int s5m8767_reg_is_enabled(struct regulator_dev *rdev)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	int ret, reg;
+	int mask = 0xc0, pattern = 0xc0;
+	u8 val;
+
+	ret = s5m8767_get_register(rdev, &reg);
+	if (ret == -EINVAL)
+		return 1;
+	else if (ret)
+		return ret;
+
+	ret = s5m_reg_read(s5m8767->iodev, reg, &val);
+	if (ret)
+		return ret;
+
+	return (val & mask) == pattern;
+}
+
+static int s5m8767_reg_enable(struct regulator_dev *rdev)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	int ret, reg;
+	int mask = 0xc0, pattern = 0xc0;
+
+	ret = s5m8767_get_register(rdev, &reg);
+	if (ret)
+		return ret;
+
+	return s5m_reg_update(s5m8767->iodev, reg, pattern, mask);
+}
+
+static int s5m8767_reg_disable(struct regulator_dev *rdev)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	int ret, reg;
+	int  mask = 0xc0, pattern = 0xc0;
+
+	ret = s5m8767_get_register(rdev, &reg);
+	if (ret)
+		return ret;
+
+	return s5m_reg_update(s5m8767->iodev, reg, ~pattern, mask);
+}
+
+static int s5m8767_get_voltage_register(struct regulator_dev *rdev, int *_reg)
+{
+	int reg_id = s5m8767_get_reg_id(rdev);
+	int reg;
+
+	switch (reg_id) {
+	case S5M8767_LDO1 ... S5M8767_LDO2:
+		reg = S5M8767_REG_LDO1CTRL + (reg_id - S5M8767_LDO1);
+		break;
+	case S5M8767_LDO3 ... S5M8767_LDO28:
+		reg = S5M8767_REG_LDO3CTRL + (reg_id - S5M8767_LDO3);
+		break;
+	case S5M8767_BUCK1:
+		reg = S5M8767_REG_BUCK1CTRL2;
+		break;
+	case S5M8767_BUCK2:
+		reg = S5M8767_REG_BUCK2DVS1;
+		break;
+	case S5M8767_BUCK3:
+		reg = S5M8767_REG_BUCK3DVS1;
+		break;
+	case S5M8767_BUCK4:
+		reg = S5M8767_REG_BUCK4DVS1;
+		break;
+	case S5M8767_BUCK5:
+		reg = S5M8767_REG_BUCK5CTRL2;
+		break;
+	case S5M8767_BUCK6 ... S5M8767_BUCK9:
+		reg = S5M8767_REG_BUCK6CTRL2 + (reg_id - S5M8767_BUCK6) * 2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	*_reg = reg;
+
+	return 0;
+}
+
+static int s5m8767_get_voltage_sel(struct regulator_dev *rdev)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	int reg, mask = 0xff, ret;
+	int reg_id = s5m8767_get_reg_id(rdev);
+	u8 val;
+
+	ret = s5m8767_get_voltage_register(rdev, &reg);
+	if (ret)
+		return ret;
+
+	switch (reg_id) {
+	case S5M8767_LDO1 ... S5M8767_LDO28:
+		mask = 0x3f;
+		break;
+	case S5M8767_BUCK2:
+		if (s5m8767->buck2_gpiodvs)
+			reg += s5m8767->buck_gpioindex;
+		break;
+	case S5M8767_BUCK3:
+		if (s5m8767->buck3_gpiodvs)
+			reg += s5m8767->buck_gpioindex;
+		break;
+	case S5M8767_BUCK4:
+		if (s5m8767->buck4_gpiodvs)
+			reg += s5m8767->buck_gpioindex;
+		break;
+	}
+
+	ret = s5m_reg_read(s5m8767->iodev, reg, &val);
+	if (ret)
+		return ret;
+
+	val &= mask;
+
+	return val;
+}
+
+static inline int s5m8767_convert_voltage(
+		const struct s5m_voltage_desc *desc,
+		int min_vol, int max_vol)
+{
+	int out_vol = 0;
+
+	if (desc == NULL)
+		return -EINVAL;
+
+	if (max_vol < desc->min || min_vol > desc->max)
+		return -EINVAL;
+
+	out_vol = (min_vol - desc->min) / desc->step;
+
+	if (desc->min + desc->step * out_vol > max_vol)
+		return -EINVAL;
+
+	return out_vol;
+}
+
+static int s5m8767_set_voltage(struct regulator_dev *rdev,
+				int min_uV, int max_uV, unsigned *selector)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	int min_vol = min_uV, max_vol = max_uV;
+	const struct s5m_voltage_desc *desc;
+	int reg_id = s5m8767_get_reg_id(rdev);
+	int reg, mask, ret;
+	int i;
+	u8 val;
+
+	switch (reg_id) {
+	case S5M8767_LDO1 ... S5M8767_LDO28:
+		mask = 0x3f;
+		break;
+	case S5M8767_BUCK1 ... S5M8767_BUCK6:
+		mask = 0xff;
+		break;
+	case S5M8767_BUCK7 ... S5M8767_BUCK8:
+		return -EINVAL;
+	case S5M8767_BUCK9:
+		mask = 0xff;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	desc = reg_voltage_map[reg_id];
+
+	i = s5m8767_convert_voltage(desc, min_vol, max_vol);
+	if (i < 0)
+		return i;
+
+	ret = s5m8767_get_voltage_register(rdev, &reg);
+	if (ret)
+		return ret;
+
+	s5m_reg_read(s5m8767->iodev, reg, &val);
+	val = val & mask;
+
+	ret = s5m_reg_write(s5m8767->iodev, reg, val);
+	*selector = i;
+
+	return ret;
+}
+
+static inline void s5m8767_set_high(struct s5m8767_info *s5m8767)
+{
+	int temp_index = s5m8767->buck_gpioindex;
+
+	gpio_set_value(s5m8767->buck_gpios[0], (temp_index >> 2) & 0x1);
+	gpio_set_value(s5m8767->buck_gpios[1], (temp_index >> 1) & 0x1);
+	gpio_set_value(s5m8767->buck_gpios[2], temp_index & 0x1);
+}
+
+static inline void s5m8767_set_low(struct s5m8767_info *s5m8767)
+{
+	int temp_index = s5m8767->buck_gpioindex;
+
+	gpio_set_value(s5m8767->buck_gpios[2], temp_index & 0x1);
+	gpio_set_value(s5m8767->buck_gpios[1], (temp_index >> 1) & 0x1);
+	gpio_set_value(s5m8767->buck_gpios[0], (temp_index >> 2) & 0x1);
+}
+
+static int s5m8767_set_voltage_buck(struct regulator_dev *rdev,
+				    int min_uV, int max_uV, unsigned *selector)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	int reg_id = s5m8767_get_reg_id(rdev);
+	const struct s5m_voltage_desc *desc;
+	int new_val, old_val, i = 0;
+	int min_vol = min_uV, max_vol = max_uV;
+
+	if (reg_id < S5M8767_BUCK1 || reg_id > S5M8767_BUCK6)
+		return -EINVAL;
+
+	switch (reg_id) {
+	case S5M8767_BUCK1:
+		return s5m8767_set_voltage(rdev, min_uV, max_uV, selector);
+	case S5M8767_BUCK2 ... S5M8767_BUCK4:
+		break;
+	case S5M8767_BUCK5 ... S5M8767_BUCK6:
+		return s5m8767_set_voltage(rdev, min_uV, max_uV, selector);
+	case S5M8767_BUCK9:
+		return s5m8767_set_voltage(rdev, min_uV, max_uV, selector);
+	}
+
+	desc = reg_voltage_map[reg_id];
+	new_val = s5m8767_convert_voltage(desc, min_vol, max_vol);
+	if (new_val < 0)
+		return new_val;
+
+	switch (reg_id) {
+	case S5M8767_BUCK2:
+		if (s5m8767->buck2_gpiodvs) {
+			while (s5m8767->buck2_vol[i] != new_val)
+				i++;
+		} else
+			return s5m8767_set_voltage(rdev, min_uV,
+						   max_uV, selector);
+		break;
+	case S5M8767_BUCK3:
+		if (s5m8767->buck3_gpiodvs) {
+			while (s5m8767->buck3_vol[i] != new_val)
+				i++;
+		} else
+			return s5m8767_set_voltage(rdev, min_uV,
+						   max_uV, selector);
+		break;
+	case S5M8767_BUCK4:
+		if (s5m8767->buck3_gpiodvs) {
+			while (s5m8767->buck4_vol[i] != new_val)
+				i++;
+		} else
+			return s5m8767_set_voltage(rdev, min_uV,
+						   max_uV, selector);
+		break;
+	}
+
+	old_val = s5m8767->buck_gpioindex;
+	s5m8767->buck_gpioindex = i;
+
+	if (i > old_val)
+		s5m8767_set_high(s5m8767);
+	else
+		s5m8767_set_low(s5m8767);
+
+	*selector = new_val;
+	return 0;
+}
+
+static int s5m8767_set_voltage_time_sel(struct regulator_dev *rdev,
+					     unsigned int old_sel,
+					     unsigned int new_sel)
+{
+	struct s5m8767_info *s5m8767 = rdev_get_drvdata(rdev);
+	const struct s5m_voltage_desc *desc;
+	int reg_id = s5m8767_get_reg_id(rdev);
+	int mask;
+	int new_val, old_val;
+
+	switch (reg_id) {
+	case S5M8767_LDO1 ... S5M8767_LDO28:
+		mask = 0x3f;
+		break;
+	case S5M8767_BUCK1 ... S5M8767_BUCK6:
+		mask = 0xff;
+		break;
+	case S5M8767_BUCK7 ... S5M8767_BUCK8:
+		return -EINVAL;
+	case S5M8767_BUCK9:
+		mask = 0xff;
+		break;
+	default:
+		return -EINVAL;
+	}
+	desc = reg_voltage_map[reg_id];
+
+	new_val = s5m8767_convert_voltage(desc, new_sel, new_sel);
+	if (new_val < 0)
+		return new_val;
+
+	old_val = s5m8767_convert_voltage(desc, old_sel, old_sel);
+	if (old_val < 0)
+		return old_val;
+
+	if (old_sel < new_sel)
+		return DIV_ROUND_UP(desc->step * (new_val - old_val),
+					s5m8767->ramp_delay);
+	else
+		return 0;
+}
+
+static struct regulator_ops s5m8767_ldo_ops = {
+	.list_voltage		= s5m8767_list_voltage,
+	.is_enabled		= s5m8767_reg_is_enabled,
+	.enable			= s5m8767_reg_enable,
+	.disable		= s5m8767_reg_disable,
+	.get_voltage_sel	= s5m8767_get_voltage_sel,
+	.set_voltage		= s5m8767_set_voltage,
+	.set_voltage_time_sel	= s5m8767_set_voltage_time_sel,
+};
+
+static struct regulator_ops s5m8767_buck_ops = {
+	.list_voltage		= s5m8767_list_voltage,
+	.is_enabled		= s5m8767_reg_is_enabled,
+	.enable			= s5m8767_reg_enable,
+	.disable		= s5m8767_reg_disable,
+	.get_voltage_sel	= s5m8767_get_voltage_sel,
+	.set_voltage		= s5m8767_set_voltage_buck,
+	.set_voltage_time_sel	= s5m8767_set_voltage_time_sel,
+};
+
+#define regulator_desc_ldo(num)		{	\
+	.name		= "LDO"#num,		\
+	.id		= S5M8767_LDO##num,	\
+	.ops		= &s5m8767_ldo_ops,	\
+	.type		= REGULATOR_VOLTAGE,	\
+	.owner		= THIS_MODULE,		\
+}
+#define regulator_desc_buck(num)	{	\
+	.name		= "BUCK"#num,		\
+	.id		= S5M8767_BUCK##num,	\
+	.ops		= &s5m8767_buck_ops,	\
+	.type		= REGULATOR_VOLTAGE,	\
+	.owner		= THIS_MODULE,		\
+}
+
+static struct regulator_desc regulators[] = {
+	regulator_desc_ldo(1),
+	regulator_desc_ldo(2),
+	regulator_desc_ldo(3),
+	regulator_desc_ldo(4),
+	regulator_desc_ldo(5),
+	regulator_desc_ldo(6),
+	regulator_desc_ldo(7),
+	regulator_desc_ldo(8),
+	regulator_desc_ldo(9),
+	regulator_desc_ldo(10),
+	regulator_desc_ldo(11),
+	regulator_desc_ldo(12),
+	regulator_desc_ldo(13),
+	regulator_desc_ldo(14),
+	regulator_desc_ldo(15),
+	regulator_desc_ldo(16),
+	regulator_desc_ldo(17),
+	regulator_desc_ldo(18),
+	regulator_desc_ldo(19),
+	regulator_desc_ldo(20),
+	regulator_desc_ldo(21),
+	regulator_desc_ldo(22),
+	regulator_desc_ldo(23),
+	regulator_desc_ldo(24),
+	regulator_desc_ldo(25),
+	regulator_desc_ldo(26),
+	regulator_desc_ldo(27),
+	regulator_desc_ldo(28),
+	regulator_desc_buck(1),
+	regulator_desc_buck(2),
+	regulator_desc_buck(3),
+	regulator_desc_buck(4),
+	regulator_desc_buck(5),
+	regulator_desc_buck(6),
+	regulator_desc_buck(7),
+	regulator_desc_buck(8),
+	regulator_desc_buck(9),
+};
+
+static __devinit int s5m8767_pmic_probe(struct platform_device *pdev)
+{
+	struct s5m87xx_dev *iodev = dev_get_drvdata(pdev->dev.parent);
+	struct s5m_platform_data *pdata = dev_get_platdata(iodev->dev);
+	struct regulator_dev **rdev;
+	struct s5m8767_info *s5m8767;
+	struct i2c_client *i2c;
+	int i, ret, size, reg;
+
+	if (!pdata) {
+		dev_err(pdev->dev.parent, "Platform data not supplied\n");
+		return -ENODEV;
+	}
+
+	s5m8767 = devm_kzalloc(&pdev->dev, sizeof(struct s5m8767_info),
+				GFP_KERNEL);
+	if (!s5m8767)
+		return -ENOMEM;
+
+	size = sizeof(struct regulator_dev *) * (S5M8767_REG_MAX - 2);
+	s5m8767->rdev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
+	if (!s5m8767->rdev)
+		return -ENOMEM;
+
+	rdev = s5m8767->rdev;
+	s5m8767->dev = &pdev->dev;
+	s5m8767->iodev = iodev;
+	s5m8767->num_regulators = S5M8767_REG_MAX - 2;
+	platform_set_drvdata(pdev, s5m8767);
+	i2c = s5m8767->iodev->i2c;
+
+	s5m8767->buck_gpioindex = pdata->buck_default_idx;
+	s5m8767->buck2_gpiodvs = pdata->buck2_gpiodvs;
+	s5m8767->buck3_gpiodvs = pdata->buck3_gpiodvs;
+	s5m8767->buck4_gpiodvs = pdata->buck4_gpiodvs;
+	s5m8767->buck_gpios[0] = pdata->buck_gpios[0];
+	s5m8767->buck_gpios[1] = pdata->buck_gpios[1];
+	s5m8767->buck_gpios[2] = pdata->buck_gpios[2];
+	s5m8767->ramp_delay = pdata->buck_ramp_delay;
+	s5m8767->buck2_ramp = pdata->buck2_ramp_enable;
+	s5m8767->buck3_ramp = pdata->buck3_ramp_enable;
+	s5m8767->buck4_ramp = pdata->buck4_ramp_enable;
+
+	for (i = 0; i < 8; i++) {
+		if (s5m8767->buck2_gpiodvs) {
+			s5m8767->buck2_vol[i] =
+				s5m8767_convert_voltage(
+						&buck_voltage_val2,
+						pdata->buck2_voltage[i],
+						pdata->buck2_voltage[i] +
+						buck_voltage_val2.step);
+		}
+
+		if (s5m8767->buck3_gpiodvs) {
+			s5m8767->buck3_vol[i] =
+				s5m8767_convert_voltage(
+						&buck_voltage_val2,
+						pdata->buck3_voltage[i],
+						pdata->buck3_voltage[i] +
+						buck_voltage_val2.step);
+		}
+
+		if (s5m8767->buck4_gpiodvs) {
+			s5m8767->buck4_vol[i] =
+				s5m8767_convert_voltage(
+						&buck_voltage_val2,
+						pdata->buck4_voltage[i],
+						pdata->buck4_voltage[i] +
+						buck_voltage_val2.step);
+		}
+	}
+
+	if (pdata->buck2_gpiodvs || pdata->buck3_gpiodvs ||
+		pdata->buck4_gpiodvs) {
+		if (gpio_is_valid(pdata->buck_gpios[0]) &&
+			gpio_is_valid(pdata->buck_gpios[1]) &&
+			gpio_is_valid(pdata->buck_gpios[2])) {
+			ret = gpio_request(pdata->buck_gpios[0],
+						"S5M8767 SET1");
+			if (ret == -EBUSY)
+				dev_warn(&pdev->dev, "Duplicated gpio request for SET1\n");
+
+			ret = gpio_request(pdata->buck_gpios[1],
+					   "S5M8767 SET2");
+			if (ret == -EBUSY)
+				dev_warn(&pdev->dev, "Duplicated gpio request for SET2\n");
+
+			ret = gpio_request(pdata->buck_gpios[2],
+					   "S5M8767 SET3");
+			if (ret == -EBUSY)
+				dev_warn(&pdev->dev, "Duplicated gpio request for SET3\n");
+			/* SET1 GPIO */
+			gpio_direction_output(pdata->buck_gpios[0],
+					(s5m8767->buck_gpioindex >> 2) & 0x1);
+			/* SET2 GPIO */
+			gpio_direction_output(pdata->buck_gpios[1],
+					(s5m8767->buck_gpioindex >> 1) & 0x1);
+			/* SET3 GPIO */
+			gpio_direction_output(pdata->buck_gpios[2],
+					(s5m8767->buck_gpioindex >> 0) & 0x1);
+			ret = 0;
+		} else {
+			dev_err(&pdev->dev, "GPIO NOT VALID\n");
+			ret = -EINVAL;
+			return ret;
+		}
+	}
+
+	if (pdata->buck2_gpiodvs) {
+		if (pdata->buck3_gpiodvs || pdata->buck4_gpiodvs) {
+			dev_err(&pdev->dev, "S5M8767 GPIO DVS NOT VALID\n");
+			ret = -EINVAL;
+			return ret;
+		}
+	}
+
+	if (pdata->buck3_gpiodvs) {
+		if (pdata->buck2_gpiodvs || pdata->buck4_gpiodvs) {
+			dev_err(&pdev->dev, "S5M8767 GPIO DVS NOT VALID\n");
+			ret = -EINVAL;
+			return ret;
+		}
+	}
+
+	if (pdata->buck4_gpiodvs) {
+		if (pdata->buck2_gpiodvs || pdata->buck3_gpiodvs) {
+			dev_err(&pdev->dev, "S5M8767 GPIO DVS NOT VALID\n");
+			ret = -EINVAL;
+			return ret;
+		}
+	}
+
+	s5m_reg_update(s5m8767->iodev, S5M8767_REG_BUCK2CTRL,
+			(pdata->buck2_gpiodvs) ? (1 << 1) : (0 << 1), 1 << 1);
+	s5m_reg_update(s5m8767->iodev, S5M8767_REG_BUCK3CTRL,
+			(pdata->buck3_gpiodvs) ? (1 << 1) : (0 << 1), 1 << 1);
+	s5m_reg_update(s5m8767->iodev, S5M8767_REG_BUCK4CTRL,
+			(pdata->buck4_gpiodvs) ? (1 << 1) : (0 << 1), 1 << 1);
+
+	/* Initialize GPIO DVS registers */
+	for (i = 0; i < 8; i++) {
+		if (s5m8767->buck2_gpiodvs) {
+			s5m_reg_write(s5m8767->iodev, S5M8767_REG_BUCK2DVS1 + i,
+					   s5m8767->buck2_vol[i]);
+		}
+
+		if (s5m8767->buck3_gpiodvs) {
+			s5m_reg_write(s5m8767->iodev, S5M8767_REG_BUCK3DVS1 + i,
+					   s5m8767->buck3_vol[i]);
+		}
+
+		if (s5m8767->buck4_gpiodvs) {
+			s5m_reg_write(s5m8767->iodev, S5M8767_REG_BUCK4DVS1 + i,
+					   s5m8767->buck4_vol[i]);
+		}
+	}
+	s5m_reg_update(s5m8767->iodev, S5M8767_REG_BUCK2CTRL, 0x78, 0xff);
+	s5m_reg_update(s5m8767->iodev, S5M8767_REG_BUCK3CTRL, 0x58, 0xff);
+	s5m_reg_update(s5m8767->iodev, S5M8767_REG_BUCK4CTRL, 0x78, 0xff);
+
+	if (s5m8767->buck2_ramp)
+		s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP, 0x08, 0x08);
+
+	if (s5m8767->buck3_ramp)
+		s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP, 0x04, 0x04);
+
+	if (s5m8767->buck4_ramp)
+		s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP, 0x02, 0x02);
+
+	if (s5m8767->buck2_ramp || s5m8767->buck3_ramp
+		|| s5m8767->buck4_ramp) {
+		switch (s5m8767->ramp_delay) {
+		case 15:
+			s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP,
+					0xc0, 0xf0);
+		case 25:
+			s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP,
+					0xd0, 0xf0);
+		case 50:
+			s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP,
+					0xe0, 0xf0);
+		case 100:
+			s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP,
+					0xf0, 0xf0);
+		default:
+			s5m_reg_update(s5m8767->iodev, S5M8767_REG_DVSRAMP,
+					0x90, 0xf0);
+		}
+	}
+
+	for (i = 0; i < pdata->num_regulators; i++) {
+		const struct s5m_voltage_desc *desc;
+		int id = pdata->regulators[i].id;
+
+		desc = reg_voltage_map[id];
+		if (desc)
+			regulators[id].n_voltages =
+				(desc->max - desc->min) / desc->step + 1;
+
+		rdev[i] = regulator_register(&regulators[id], s5m8767->dev,
+				pdata->regulators[i].initdata, s5m8767);
+		if (IS_ERR(rdev[i])) {
+			ret = PTR_ERR(rdev[i]);
+			dev_err(s5m8767->dev, "regulator init failed for %d\n",
+					id);
+			rdev[i] = NULL;
+			goto err;
+		}
+	}
+
+	return 0;
+err:
+	for (i = 0; i < s5m8767->num_regulators; i++)
+		if (rdev[i])
+			regulator_unregister(rdev[i]);
+
+	return ret;
+}
+
+static int __devexit s5m8767_pmic_remove(struct platform_device *pdev)
+{
+	struct s5m8767_info *s5m8767 = platform_get_drvdata(pdev);
+	struct regulator_dev **rdev = s5m8767->rdev;
+	int i;
+
+	for (i = 0; i < s5m8767->num_regulators; i++)
+		if (rdev[i])
+			regulator_unregister(rdev[i]);
+
+	return 0;
+}
+
+static const struct platform_device_id s5m8767_pmic_id[] = {
+	{ "s5m8767-pmic", 0},
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, s5m8767_pmic_id);
+
+static struct platform_driver s5m8767_pmic_driver = {
+	.driver = {
+		.name = "s5m8767-pmic",
+		.owner = THIS_MODULE,
+	},
+	.probe = s5m8767_pmic_probe,
+	.remove = __devexit_p(s5m8767_pmic_remove),
+	.id_table = s5m8767_pmic_id,
+};
+
+static int __init s5m8767_pmic_init(void)
+{
+	return platform_driver_register(&s5m8767_pmic_driver);
+}
+subsys_initcall(s5m8767_pmic_init);
+
+static void __exit s5m8767_pmic_exit(void)
+{
+	platform_driver_unregister(&s5m8767_pmic_driver);
+}
+module_exit(s5m8767_pmic_exit);
+
+/* Module information */
+MODULE_AUTHOR("Sangbeom Kim <sbkim73@samsung.com>");
+MODULE_DESCRIPTION("SAMSUNG S5M8767 Regulator Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:s5m8767-pmic");