drivers/regulator/max77686.c - linux - Git at Google

 /*
  * max77686.c - Regulator driver for the Maxim 77686
  *
  * Copyright (C) 2012 Samsung Electronics
  * Chiwoong Byun <woong.byun@smasung.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/delay.h>
 #include <linux/err.h>
 #include <linux/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_RAMP_DELAY	100000			/* uV/us */
 #define MAX77686_DVS_RAMP_DELAY	27500			/* uV/us */
 #define MAX77686_DVS_MINUV	600000
 #define MAX77686_DVS_UVSTEP	12500

 #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 {
 	struct regulator_dev *rdev[MAX77686_REGULATORS];
 	unsigned int opmode[MAX77686_REGULATORS];
 };

 /* Some BUCKS supports Normal[ON/OFF] mode during suspend */
 static int max77686_buck_set_suspend_disable(struct regulator_dev *rdev)
 {
 	unsigned int val;
 	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

 	if (rdev->desc->id == MAX77686_BUCK1)
 		val = 0x1;
 	else
 		val = 0x1 << MAX77686_OPMODE_BUCK234_SHIFT;

 	max77686->opmode[rdev->desc->id] = val;
 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  rdev->desc->enable_mask,
 				  val);
 }

 /* 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;

 	/* BUCK[5-9] doesn't support this feature */
 	if (rdev->desc->id >= MAX77686_BUCK5)
 		return 0;

 	switch (mode) {
 	case REGULATOR_MODE_IDLE:			/* ON in LP Mode */
 		val = 0x2 << MAX77686_OPMODE_SHIFT;
 		break;
 	case REGULATOR_MODE_NORMAL:			/* ON in Normal Mode */
 		val = 0x3 << MAX77686_OPMODE_SHIFT;
 		break;
 	default:
 		pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
 			rdev->desc->name, mode);
 		return -EINVAL;
 	}

 	max77686->opmode[rdev->desc->id] = val;
 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  rdev->desc->enable_mask,
 				  val);
 }

 /* 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);

 	switch (mode) {
 	case REGULATOR_MODE_STANDBY:			/* switch off */
 		val = 0x1 << MAX77686_OPMODE_SHIFT;
 		break;
 	case REGULATOR_MODE_IDLE:			/* ON in LP Mode */
 		val = 0x2 << MAX77686_OPMODE_SHIFT;
 		break;
 	case REGULATOR_MODE_NORMAL:			/* ON in Normal Mode */
 		val = 0x3 << MAX77686_OPMODE_SHIFT;
 		break;
 	default:
 		pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
 			rdev->desc->name, mode);
 		return -EINVAL;
 	}

 	max77686->opmode[rdev->desc->id] = val;
 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  rdev->desc->enable_mask,
 				  val);
 }

 static int max77686_enable(struct regulator_dev *rdev)
 {
 	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  rdev->desc->enable_mask,
 				  max77686->opmode[rdev->desc->id]);
 }

 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\n",
 			rdev->desc->name, ramp_delay);
 	}

 	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 				  MAX77686_RAMP_RATE_MASK, ramp_value << 6);
 }

 static 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 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,
 };

 static 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_buck_set_suspend_disable,
 };

 static 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_buck_set_suspend_disable,
 };

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

 #ifdef CONFIG_OF
 static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
 					struct max77686_platform_data *pdata)
 {
 	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 	struct device_node *pmic_np, *regulators_np;
 	struct max77686_regulator_data *rdata;
 	struct of_regulator_match rmatch;
 	unsigned int i;

 	pmic_np = iodev->dev->of_node;
 	regulators_np = of_find_node_by_name(pmic_np, "voltage-regulators");
 	if (!regulators_np) {
 		dev_err(&pdev->dev, "could not find regulators sub-node\n");
 		return -EINVAL;
 	}

 	pdata->num_regulators = ARRAY_SIZE(regulators);
 	rdata = devm_kzalloc(&pdev->dev, sizeof(*rdata) *
 			     pdata->num_regulators, GFP_KERNEL);
 	if (!rdata) {
 		dev_err(&pdev->dev,
 			"could not allocate memory for regulator data\n");
 		return -ENOMEM;
 	}

 	for (i = 0; i < pdata->num_regulators; i++) {
 		rmatch.name = regulators[i].name;
 		rmatch.init_data = NULL;
 		rmatch.of_node = NULL;
 		of_regulator_match(&pdev->dev, regulators_np, &rmatch, 1);
 		rdata[i].initdata = rmatch.init_data;
 		rdata[i].of_node = rmatch.of_node;
 	}

 	pdata->regulators = rdata;

 	return 0;
 }
 #else
 static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
 					struct max77686_platform_data *pdata)
 {
 	return 0;
 }
 #endif /* CONFIG_OF */

 static int max77686_pmic_probe(struct platform_device *pdev)
 {
 	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 	struct max77686_platform_data *pdata = dev_get_platdata(iodev->dev);
 	struct max77686_data *max77686;
 	int i, ret = 0;
 	struct regulator_config config = { };

 	dev_dbg(&pdev->dev, "%s\n", __func__);

 	if (!pdata) {
 		dev_err(&pdev->dev, "no platform data found for regulator\n");
 		return -ENODEV;
 	}

 	if (iodev->dev->of_node) {
 		ret = max77686_pmic_dt_parse_pdata(pdev, pdata);
 		if (ret)
 			return ret;
 	}

 	if (pdata->num_regulators != MAX77686_REGULATORS) {
 		dev_err(&pdev->dev,
 			"Invalid initial data for regulator's initialiation\n");
 		return -EINVAL;
 	}

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

 	config.dev = &pdev->dev;
 	config.regmap = iodev->regmap;
 	config.driver_data = max77686;
 	platform_set_drvdata(pdev, max77686);

 	for (i = 0; i < MAX77686_REGULATORS; i++) {
 		config.init_data = pdata->regulators[i].initdata;
 		config.of_node = pdata->regulators[i].of_node;

 		max77686->opmode[i] = regulators[i].enable_mask;
 		max77686->rdev[i] = regulator_register(&regulators[i], &config);
 		if (IS_ERR(max77686->rdev[i])) {
 			ret = PTR_ERR(max77686->rdev[i]);
 			dev_err(&pdev->dev,
 				"regulator init failed for %d\n", i);
 			max77686->rdev[i] = NULL;
 			goto err;
 		}
 	}

 	return 0;
 err:
 	while (--i >= 0)
 		regulator_unregister(max77686->rdev[i]);
 	return ret;
 }

 static int max77686_pmic_remove(struct platform_device *pdev)
 {
 	struct max77686_data *max77686 = platform_get_drvdata(pdev);
 	int i;

 	for (i = 0; i < MAX77686_REGULATORS; i++)
 		regulator_unregister(max77686->rdev[i]);

 	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",
 		.owner = THIS_MODULE,
 	},
 	.probe = max77686_pmic_probe,
 	.remove = max77686_pmic_remove,
 	.id_table = max77686_pmic_id,
 };

 static int __init max77686_pmic_init(void)
 {
 	return platform_driver_register(&max77686_pmic_driver);
 }
 subsys_initcall(max77686_pmic_init);

 static void __exit max77686_pmic_cleanup(void)
 {
 	platform_driver_unregister(&max77686_pmic_driver);
 }
 module_exit(max77686_pmic_cleanup);

 MODULE_DESCRIPTION("MAXIM 77686 Regulator Driver");
 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
 MODULE_LICENSE("GPL");
	/*
	* max77686.c - Regulator driver for the Maxim 77686
	*
	* Copyright (C) 2012 Samsung Electronics
	* Chiwoong Byun <woong.byun@smasung.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/delay.h>
	#include <linux/err.h>
	#include <linux/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_RAMP_DELAY 100000 /* uV/us */
	#define MAX77686_DVS_RAMP_DELAY 27500 /* uV/us */
	#define MAX77686_DVS_MINUV 600000
	#define MAX77686_DVS_UVSTEP 12500

	#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 {
	struct regulator_dev *rdev[MAX77686_REGULATORS];
	unsigned int opmode[MAX77686_REGULATORS];
	};

	/* Some BUCKS supports Normal[ON/OFF] mode during suspend */
	static int max77686_buck_set_suspend_disable(struct regulator_dev *rdev)
	{
	unsigned int val;
	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

	if (rdev->desc->id == MAX77686_BUCK1)
	val = 0x1;
	else
	val = 0x1 << MAX77686_OPMODE_BUCK234_SHIFT;

	max77686->opmode[rdev->desc->id] = val;
	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
	rdev->desc->enable_mask,
	val);
	}

	/* 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;

	/* BUCK[5-9] doesn't support this feature */
	if (rdev->desc->id >= MAX77686_BUCK5)
	return 0;

	switch (mode) {
	case REGULATOR_MODE_IDLE: /* ON in LP Mode */
	val = 0x2 << MAX77686_OPMODE_SHIFT;
	break;
	case REGULATOR_MODE_NORMAL: /* ON in Normal Mode */
	val = 0x3 << MAX77686_OPMODE_SHIFT;
	break;
	default:
	pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
	rdev->desc->name, mode);
	return -EINVAL;
	}

	max77686->opmode[rdev->desc->id] = val;
	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
	rdev->desc->enable_mask,
	val);
	}

	/* 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);

	switch (mode) {
	case REGULATOR_MODE_STANDBY: /* switch off */
	val = 0x1 << MAX77686_OPMODE_SHIFT;
	break;
	case REGULATOR_MODE_IDLE: /* ON in LP Mode */
	val = 0x2 << MAX77686_OPMODE_SHIFT;
	break;
	case REGULATOR_MODE_NORMAL: /* ON in Normal Mode */
	val = 0x3 << MAX77686_OPMODE_SHIFT;
	break;
	default:
	pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
	rdev->desc->name, mode);
	return -EINVAL;
	}

	max77686->opmode[rdev->desc->id] = val;
	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
	rdev->desc->enable_mask,
	val);
	}

	static int max77686_enable(struct regulator_dev *rdev)
	{
	struct max77686_data *max77686 = rdev_get_drvdata(rdev);

	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
	rdev->desc->enable_mask,
	max77686->opmode[rdev->desc->id]);
	}

	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\n",
	rdev->desc->name, ramp_delay);
	}

	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
	MAX77686_RAMP_RATE_MASK, ramp_value << 6);
	}

	static 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 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,
	};

	static 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_buck_set_suspend_disable,
	};

	static 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_buck_set_suspend_disable,
	};

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

	#ifdef CONFIG_OF
	static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
	struct max77686_platform_data *pdata)
	{
	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
	struct device_node pmic_np, regulators_np;
	struct max77686_regulator_data *rdata;
	struct of_regulator_match rmatch;
	unsigned int i;

	pmic_np = iodev->dev->of_node;
	regulators_np = of_find_node_by_name(pmic_np, "voltage-regulators");
	if (!regulators_np) {
	dev_err(&pdev->dev, "could not find regulators sub-node\n");
	return -EINVAL;
	}

	pdata->num_regulators = ARRAY_SIZE(regulators);
	rdata = devm_kzalloc(&pdev->dev, sizeof(rdata)
	pdata->num_regulators, GFP_KERNEL);
	if (!rdata) {
	dev_err(&pdev->dev,
	"could not allocate memory for regulator data\n");
	return -ENOMEM;
	}

	for (i = 0; i < pdata->num_regulators; i++) {
	rmatch.name = regulators[i].name;
	rmatch.init_data = NULL;
	rmatch.of_node = NULL;
	of_regulator_match(&pdev->dev, regulators_np, &rmatch, 1);
	rdata[i].initdata = rmatch.init_data;
	rdata[i].of_node = rmatch.of_node;
	}

	pdata->regulators = rdata;

	return 0;
	}
	#else
	static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
	struct max77686_platform_data *pdata)
	{
	return 0;
	}
	#endif /* CONFIG_OF */

	static int max77686_pmic_probe(struct platform_device *pdev)
	{
	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
	struct max77686_platform_data *pdata = dev_get_platdata(iodev->dev);
	struct max77686_data *max77686;
	int i, ret = 0;
	struct regulator_config config = { };

	dev_dbg(&pdev->dev, "%s\n", __func__);

	if (!pdata) {
	dev_err(&pdev->dev, "no platform data found for regulator\n");
	return -ENODEV;
	}

	if (iodev->dev->of_node) {
	ret = max77686_pmic_dt_parse_pdata(pdev, pdata);
	if (ret)
	return ret;
	}

	if (pdata->num_regulators != MAX77686_REGULATORS) {
	dev_err(&pdev->dev,
	"Invalid initial data for regulator's initialiation\n");
	return -EINVAL;
	}

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

	config.dev = &pdev->dev;
	config.regmap = iodev->regmap;
	config.driver_data = max77686;
	platform_set_drvdata(pdev, max77686);

	for (i = 0; i < MAX77686_REGULATORS; i++) {
	config.init_data = pdata->regulators[i].initdata;
	config.of_node = pdata->regulators[i].of_node;

	max77686->opmode[i] = regulators[i].enable_mask;
	max77686->rdev[i] = regulator_register(&regulators[i], &config);
	if (IS_ERR(max77686->rdev[i])) {
	ret = PTR_ERR(max77686->rdev[i]);
	dev_err(&pdev->dev,
	"regulator init failed for %d\n", i);
	max77686->rdev[i] = NULL;
	goto err;
	}
	}

	return 0;
	err:
	while (--i >= 0)
	regulator_unregister(max77686->rdev[i]);
	return ret;
	}

	static int max77686_pmic_remove(struct platform_device *pdev)
	{
	struct max77686_data *max77686 = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < MAX77686_REGULATORS; i++)
	regulator_unregister(max77686->rdev[i]);

	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",
	.owner = THIS_MODULE,
	},
	.probe = max77686_pmic_probe,
	.remove = max77686_pmic_remove,
	.id_table = max77686_pmic_id,
	};

	static int __init max77686_pmic_init(void)
	{
	return platform_driver_register(&max77686_pmic_driver);
	}
	subsys_initcall(max77686_pmic_init);

	static void __exit max77686_pmic_cleanup(void)
	{
	platform_driver_unregister(&max77686_pmic_driver);
	}
	module_exit(max77686_pmic_cleanup);

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