/*
   * max77686.c - Regulator driver for the Maxim 77686
   *
   * Copyright (C) 2012 Samsung Electronics

   * Chiwoong Byun <woong.byun@samsung.com>

   * Jonghwa Lee <jonghwa3.lee@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.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   *
   * This driver is based on max8997.c
   */
  
  #include <linux/kernel.h>
  #include <linux/bug.h>

  #include <linux/err.h>
  #include <linux/gpio.h>

  #include <linux/of_gpio.h>

  #include <linux/slab.h>
  #include <linux/platform_device.h>
  #include <linux/regulator/driver.h>
  #include <linux/regulator/machine.h>

  #include <linux/regulator/of_regulator.h>

  #include <linux/mfd/max77686.h>
  #include <linux/mfd/max77686-private.h>
  
  #define MAX77686_LDO_MINUV	800000
  #define MAX77686_LDO_UVSTEP	50000
  #define MAX77686_LDO_LOW_MINUV	800000
  #define MAX77686_LDO_LOW_UVSTEP	25000
  #define MAX77686_BUCK_MINUV	750000
  #define MAX77686_BUCK_UVSTEP	50000

  #define MAX77686_BUCK_ENABLE_TIME	40		/* us */
  #define MAX77686_DVS_ENABLE_TIME	22		/* us */

  #define MAX77686_RAMP_DELAY	100000			/* uV/us */
  #define MAX77686_DVS_RAMP_DELAY	27500			/* uV/us */

  #define MAX77686_DVS_MINUV	600000
  #define MAX77686_DVS_UVSTEP	12500

  /*

   * Value for configuring buck[89] and LDO{20,21,22} as GPIO control.
   * It is the same as 'off' for other regulators.
   */
  #define MAX77686_GPIO_CONTROL		0x0
  /*

   * Values used for configuring LDOs and bucks.
   * Forcing low power mode: LDO1, 3-5, 9, 13, 17-26
   */
  #define MAX77686_LDO_LOWPOWER		0x1
  /*
   * On/off controlled by PWRREQ:
   *  - LDO2, 6-8, 10-12, 14-16
   *  - buck[1234]
   */
  #define MAX77686_OFF_PWRREQ		0x1
  /* Low power mode controlled by PWRREQ: All LDOs */
  #define MAX77686_LDO_LOWPOWER_PWRREQ	0x2
  /* Forcing low power mode: buck[234] */
  #define MAX77686_BUCK_LOWPOWER		0x2
  #define MAX77686_NORMAL			0x3

  #define MAX77686_OPMODE_SHIFT	6
  #define MAX77686_OPMODE_BUCK234_SHIFT	4
  #define MAX77686_OPMODE_MASK	0x3
  
  #define MAX77686_VSEL_MASK	0x3F
  #define MAX77686_DVS_VSEL_MASK	0xFF
  
  #define MAX77686_RAMP_RATE_MASK	0xC0
  
  #define MAX77686_REGULATORS	MAX77686_REG_MAX
  #define MAX77686_LDOS		26
  
  enum max77686_ramp_rate {
  	RAMP_RATE_13P75MV,
  	RAMP_RATE_27P5MV,
  	RAMP_RATE_55MV,
  	RAMP_RATE_NO_CTRL,	/* 100mV/us */
  };
  
  struct max77686_data {

  	DECLARE_BITMAP(gpio_enabled, MAX77686_REGULATORS);

  	/* Array indexed by regulator id */

  	unsigned int opmode[MAX77686_REGULATORS];

  };

  static unsigned int max77686_get_opmode_shift(int id)
  {
  	switch (id) {
  	case MAX77686_BUCK1:
  	case MAX77686_BUCK5 ... MAX77686_BUCK9:
  		return 0;
  	case MAX77686_BUCK2 ... MAX77686_BUCK4:
  		return MAX77686_OPMODE_BUCK234_SHIFT;
  	default:
  		/* all LDOs */
  		return MAX77686_OPMODE_SHIFT;
  	}
  }

  /*
   * When regulator is configured for GPIO control then it
   * replaces "normal" mode. Any change from low power mode to normal
   * should actually change to GPIO control.
   * Map normal mode to proper value for such regulators.
   */
  static unsigned int max77686_map_normal_mode(struct max77686_data *max77686,
  					     int id)
  {
  	switch (id) {
  	case MAX77686_BUCK8:
  	case MAX77686_BUCK9:
  	case MAX77686_LDO20 ... MAX77686_LDO22:

  		if (test_bit(id, max77686->gpio_enabled))

  			return MAX77686_GPIO_CONTROL;
  	}
  
  	return MAX77686_NORMAL;
  }

  /* Some BUCKs and LDOs supports Normal[ON/OFF] mode during suspend */
  static int max77686_set_suspend_disable(struct regulator_dev *rdev)

  {

  	unsigned int val, shift;

  	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

  	int ret, id = rdev_get_id(rdev);

  	shift = max77686_get_opmode_shift(id);
  	val = MAX77686_OFF_PWRREQ;

  	ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,

  				 rdev->desc->enable_mask, val << shift);

  	if (ret)
  		return ret;

  	max77686->opmode[id] = val;

  	return 0;

  }
  
  /* Some LDOs supports [LPM/Normal]ON mode during suspend state */
  static int max77686_set_suspend_mode(struct regulator_dev *rdev,
  				     unsigned int mode)
  {
  	struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  	unsigned int val;

  	int ret, id = rdev_get_id(rdev);

  
  	/* BUCK[5-9] doesn't support this feature */

  	if (id >= MAX77686_BUCK5)

  		return 0;
  
  	switch (mode) {
  	case REGULATOR_MODE_IDLE:			/* ON in LP Mode */

  		val = MAX77686_LDO_LOWPOWER_PWRREQ;

  		break;
  	case REGULATOR_MODE_NORMAL:			/* ON in Normal Mode */

  		val = max77686_map_normal_mode(max77686, id);

  		break;
  	default:
  		pr_warn("%s: regulator_suspend_mode : 0x%x not supported
  ",
  			rdev->desc->name, mode);
  		return -EINVAL;
  	}

  	ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,

  				  rdev->desc->enable_mask,
  				  val << MAX77686_OPMODE_SHIFT);

  	if (ret)
  		return ret;

  	max77686->opmode[id] = val;

  	return 0;

  }
  
  /* Some LDOs supports LPM-ON/OFF/Normal-ON mode during suspend state */
  static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
  				     unsigned int mode)
  {
  	unsigned int val;
  	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

  	int ret, id = rdev_get_id(rdev);

  
  	switch (mode) {
  	case REGULATOR_MODE_STANDBY:			/* switch off */

  		val = MAX77686_OFF_PWRREQ;

  		break;
  	case REGULATOR_MODE_IDLE:			/* ON in LP Mode */

  		val = MAX77686_LDO_LOWPOWER_PWRREQ;

  		break;
  	case REGULATOR_MODE_NORMAL:			/* ON in Normal Mode */

  		val = max77686_map_normal_mode(max77686, id);

  		break;
  	default:
  		pr_warn("%s: regulator_suspend_mode : 0x%x not supported
  ",
  			rdev->desc->name, mode);
  		return -EINVAL;
  	}

  	ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,

  				 rdev->desc->enable_mask,
  				 val << MAX77686_OPMODE_SHIFT);

  	if (ret)
  		return ret;

  	max77686->opmode[id] = val;

  	return 0;

  }

  static int max77686_enable(struct regulator_dev *rdev)

  {
  	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

  	unsigned int shift;
  	int id = rdev_get_id(rdev);
  
  	shift = max77686_get_opmode_shift(id);

  	if (max77686->opmode[id] == MAX77686_OFF_PWRREQ)

  		max77686->opmode[id] = max77686_map_normal_mode(max77686, id);

  	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  				  rdev->desc->enable_mask,

  				  max77686->opmode[id] << shift);

  }

  static int max77686_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
  {
  	unsigned int ramp_value = RAMP_RATE_NO_CTRL;
  
  	switch (ramp_delay) {
  	case 1 ... 13750:
  		ramp_value = RAMP_RATE_13P75MV;
  		break;
  	case 13751 ... 27500:
  		ramp_value = RAMP_RATE_27P5MV;
  		break;
  	case 27501 ... 55000:
  		ramp_value = RAMP_RATE_55MV;
  		break;
  	case 55001 ... 100000:
  		break;
  	default:
  		pr_warn("%s: ramp_delay: %d not supported, setting 100000
  ",
  			rdev->desc->name, ramp_delay);
  	}
  
  	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  				  MAX77686_RAMP_RATE_MASK, ramp_value << 6);
  }

  static int max77686_of_parse_cb(struct device_node *np,
  		const struct regulator_desc *desc,
  		struct regulator_config *config)
  {
  	struct max77686_data *max77686 = config->driver_data;
  
  	switch (desc->id) {
  	case MAX77686_BUCK8:
  	case MAX77686_BUCK9:
  	case MAX77686_LDO20 ... MAX77686_LDO22:
  		config->ena_gpio = of_get_named_gpio(np,
  					"maxim,ena-gpios", 0);
  		config->ena_gpio_flags = GPIOF_OUT_INIT_HIGH;
  		config->ena_gpio_initialized = true;
  		break;
  	default:
  		return 0;
  	}
  
  	if (gpio_is_valid(config->ena_gpio)) {

  		set_bit(desc->id, max77686->gpio_enabled);

  
  		return regmap_update_bits(config->regmap, desc->enable_reg,
  					  desc->enable_mask,
  					  MAX77686_GPIO_CONTROL);
  	}
  
  	return 0;
  }

  static const struct regulator_ops max77686_ops = {

  	.list_voltage		= regulator_list_voltage_linear,

  	.map_voltage		= regulator_map_voltage_linear,

  	.is_enabled		= regulator_is_enabled_regmap,

  	.enable			= max77686_enable,

  	.disable		= regulator_disable_regmap,
  	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
  	.set_voltage_sel	= regulator_set_voltage_sel_regmap,

  	.set_voltage_time_sel	= regulator_set_voltage_time_sel,

  	.set_suspend_mode	= max77686_set_suspend_mode,
  };

  static const struct regulator_ops max77686_ldo_ops = {

  	.list_voltage		= regulator_list_voltage_linear,
  	.map_voltage		= regulator_map_voltage_linear,
  	.is_enabled		= regulator_is_enabled_regmap,
  	.enable			= max77686_enable,

  	.disable		= regulator_disable_regmap,
  	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
  	.set_voltage_sel	= regulator_set_voltage_sel_regmap,

  	.set_voltage_time_sel	= regulator_set_voltage_time_sel,

  	.set_suspend_mode	= max77686_ldo_set_suspend_mode,

  	.set_suspend_disable	= max77686_set_suspend_disable,

  };

  static const struct regulator_ops max77686_buck1_ops = {

  	.list_voltage		= regulator_list_voltage_linear,
  	.map_voltage		= regulator_map_voltage_linear,
  	.is_enabled		= regulator_is_enabled_regmap,
  	.enable			= max77686_enable,
  	.disable		= regulator_disable_regmap,
  	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
  	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
  	.set_voltage_time_sel	= regulator_set_voltage_time_sel,

  	.set_suspend_disable	= max77686_set_suspend_disable,

  };

  static const struct regulator_ops max77686_buck_dvs_ops = {

  	.list_voltage		= regulator_list_voltage_linear,

  	.map_voltage		= regulator_map_voltage_linear,

  	.is_enabled		= regulator_is_enabled_regmap,

  	.enable			= max77686_enable,

  	.disable		= regulator_disable_regmap,
  	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
  	.set_voltage_sel	= regulator_set_voltage_sel_regmap,

  	.set_voltage_time_sel	= regulator_set_voltage_time_sel,

  	.set_ramp_delay		= max77686_set_ramp_delay,

  	.set_suspend_disable	= max77686_set_suspend_disable,

  };
  
  #define regulator_desc_ldo(num)		{				\
  	.name		= "LDO"#num,					\

  	.of_match	= of_match_ptr("LDO"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.of_parse_cb	= max77686_of_parse_cb,				\

  	.id		= MAX77686_LDO##num,				\
  	.ops		= &max77686_ops,				\
  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_LDO_MINUV,				\
  	.uV_step	= MAX77686_LDO_UVSTEP,				\

  	.ramp_delay	= MAX77686_RAMP_DELAY,				\

  	.n_voltages	= MAX77686_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.vsel_mask	= MAX77686_VSEL_MASK,				\
  	.enable_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.enable_mask	= MAX77686_OPMODE_MASK				\
  			<< MAX77686_OPMODE_SHIFT,			\
  }

  #define regulator_desc_lpm_ldo(num)	{				\
  	.name		= "LDO"#num,					\

  	.of_match	= of_match_ptr("LDO"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.id		= MAX77686_LDO##num,				\
  	.ops		= &max77686_ldo_ops,				\
  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_LDO_MINUV,				\
  	.uV_step	= MAX77686_LDO_UVSTEP,				\
  	.ramp_delay	= MAX77686_RAMP_DELAY,				\
  	.n_voltages	= MAX77686_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.vsel_mask	= MAX77686_VSEL_MASK,				\
  	.enable_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.enable_mask	= MAX77686_OPMODE_MASK				\
  			<< MAX77686_OPMODE_SHIFT,			\
  }

  #define regulator_desc_ldo_low(num)		{			\
  	.name		= "LDO"#num,					\

  	.of_match	= of_match_ptr("LDO"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.id		= MAX77686_LDO##num,				\

  	.ops		= &max77686_ldo_ops,				\
  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_LDO_LOW_MINUV,			\
  	.uV_step	= MAX77686_LDO_LOW_UVSTEP,			\
  	.ramp_delay	= MAX77686_RAMP_DELAY,				\
  	.n_voltages	= MAX77686_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.vsel_mask	= MAX77686_VSEL_MASK,				\
  	.enable_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.enable_mask	= MAX77686_OPMODE_MASK				\
  			<< MAX77686_OPMODE_SHIFT,			\
  }
  #define regulator_desc_ldo1_low(num)		{			\
  	.name		= "LDO"#num,					\

  	.of_match	= of_match_ptr("LDO"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.id		= MAX77686_LDO##num,				\

  	.ops		= &max77686_ops,				\
  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_LDO_LOW_MINUV,			\
  	.uV_step	= MAX77686_LDO_LOW_UVSTEP,			\

  	.ramp_delay	= MAX77686_RAMP_DELAY,				\

  	.n_voltages	= MAX77686_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.vsel_mask	= MAX77686_VSEL_MASK,				\
  	.enable_reg	= MAX77686_REG_LDO1CTRL1 + num - 1,		\
  	.enable_mask	= MAX77686_OPMODE_MASK				\
  			<< MAX77686_OPMODE_SHIFT,			\
  }
  #define regulator_desc_buck(num)		{			\
  	.name		= "BUCK"#num,					\

  	.of_match	= of_match_ptr("BUCK"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.of_parse_cb	= max77686_of_parse_cb,				\

  	.id		= MAX77686_BUCK##num,				\
  	.ops		= &max77686_ops,				\
  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_BUCK_MINUV,				\
  	.uV_step	= MAX77686_BUCK_UVSTEP,				\

  	.ramp_delay	= MAX77686_RAMP_DELAY,				\

  	.enable_time	= MAX77686_BUCK_ENABLE_TIME,			\

  	.n_voltages	= MAX77686_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_BUCK5OUT + (num - 5) * 2,	\
  	.vsel_mask	= MAX77686_VSEL_MASK,				\
  	.enable_reg	= MAX77686_REG_BUCK5CTRL + (num - 5) * 2,	\
  	.enable_mask	= MAX77686_OPMODE_MASK,				\
  }
  #define regulator_desc_buck1(num)		{			\
  	.name		= "BUCK"#num,					\

  	.of_match	= of_match_ptr("BUCK"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.id		= MAX77686_BUCK##num,				\

  	.ops		= &max77686_buck1_ops,				\

  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_BUCK_MINUV,				\
  	.uV_step	= MAX77686_BUCK_UVSTEP,				\

  	.ramp_delay	= MAX77686_RAMP_DELAY,				\

  	.enable_time	= MAX77686_BUCK_ENABLE_TIME,			\

  	.n_voltages	= MAX77686_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_BUCK1OUT,			\
  	.vsel_mask	= MAX77686_VSEL_MASK,				\
  	.enable_reg	= MAX77686_REG_BUCK1CTRL,			\
  	.enable_mask	= MAX77686_OPMODE_MASK,				\
  }
  #define regulator_desc_buck_dvs(num)		{			\
  	.name		= "BUCK"#num,					\

  	.of_match	= of_match_ptr("BUCK"#num),			\
  	.regulators_node	= of_match_ptr("voltage-regulators"),	\

  	.id		= MAX77686_BUCK##num,				\

  	.ops		= &max77686_buck_dvs_ops,			\

  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.min_uV		= MAX77686_DVS_MINUV,				\
  	.uV_step	= MAX77686_DVS_UVSTEP,				\

  	.ramp_delay	= MAX77686_DVS_RAMP_DELAY,			\

  	.enable_time	= MAX77686_DVS_ENABLE_TIME,			\

  	.n_voltages	= MAX77686_DVS_VSEL_MASK + 1,			\
  	.vsel_reg	= MAX77686_REG_BUCK2DVS1 + (num - 2) * 10,	\
  	.vsel_mask	= MAX77686_DVS_VSEL_MASK,			\
  	.enable_reg	= MAX77686_REG_BUCK2CTRL1 + (num - 2) * 10,	\
  	.enable_mask	= MAX77686_OPMODE_MASK				\
  			<< MAX77686_OPMODE_BUCK234_SHIFT,		\
  }

  static const struct regulator_desc regulators[] = {

  	regulator_desc_ldo1_low(1),

  	regulator_desc_ldo_low(2),
  	regulator_desc_ldo(3),
  	regulator_desc_ldo(4),
  	regulator_desc_ldo(5),
  	regulator_desc_ldo_low(6),
  	regulator_desc_ldo_low(7),
  	regulator_desc_ldo_low(8),
  	regulator_desc_ldo(9),

  	regulator_desc_lpm_ldo(10),
  	regulator_desc_lpm_ldo(11),
  	regulator_desc_lpm_ldo(12),

  	regulator_desc_ldo(13),

  	regulator_desc_lpm_ldo(14),

  	regulator_desc_ldo_low(15),

  	regulator_desc_lpm_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_buck1(1),
  	regulator_desc_buck_dvs(2),
  	regulator_desc_buck_dvs(3),
  	regulator_desc_buck_dvs(4),
  	regulator_desc_buck(5),
  	regulator_desc_buck(6),
  	regulator_desc_buck(7),
  	regulator_desc_buck(8),
  	regulator_desc_buck(9),
  };

  static int max77686_pmic_probe(struct platform_device *pdev)

  {
  	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);

  	struct max77686_data *max77686;

  	int i;

  	struct regulator_config config = { };

  
  	dev_dbg(&pdev->dev, "%s
  ", __func__);
  
  	max77686 = devm_kzalloc(&pdev->dev, sizeof(struct max77686_data),
  				GFP_KERNEL);
  	if (!max77686)
  		return -ENOMEM;

  	config.dev = iodev->dev;

  	config.regmap = iodev->regmap;

  	config.driver_data = max77686;

  	platform_set_drvdata(pdev, max77686);

  	for (i = 0; i < MAX77686_REGULATORS; i++) {

  		struct regulator_dev *rdev;

  		int id = regulators[i].id;

  		max77686->opmode[id] = MAX77686_NORMAL;

  		rdev = devm_regulator_register(&pdev->dev,

  						&regulators[i], &config);

  		if (IS_ERR(rdev)) {

  			int ret = PTR_ERR(rdev);

  			dev_err(&pdev->dev,

  				"regulator init failed for %d: %d
  ", i, ret);
  			return ret;

  		}

  	}

  	return 0;

  }
  
  static const struct platform_device_id max77686_pmic_id[] = {
  	{"max77686-pmic", 0},
  	{ },
  };
  MODULE_DEVICE_TABLE(platform, max77686_pmic_id);
  
  static struct platform_driver max77686_pmic_driver = {
  	.driver = {
  		.name = "max77686-pmic",

  	},
  	.probe = max77686_pmic_probe,

  	.id_table = max77686_pmic_id,
  };

  module_platform_driver(max77686_pmic_driver);

  
  MODULE_DESCRIPTION("MAXIM 77686 Regulator Driver");
  MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
  MODULE_LICENSE("GPL");