/*
   * max77693.c - Regulator driver for the Maxim 77693
   *
   * Copyright (C) 2013 Samsung Electronics
   * 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 max77686.c
   */
  
  #include <linux/err.h>
  #include <linux/slab.h>
  #include <linux/platform_device.h>
  #include <linux/module.h>
  #include <linux/export.h>
  #include <linux/regulator/driver.h>
  #include <linux/regulator/machine.h>
  #include <linux/mfd/max77693.h>
  #include <linux/mfd/max77693-private.h>
  #include <linux/regulator/of_regulator.h>

  #include <linux/regmap.h>

  
  #define CHGIN_ILIM_STEP_20mA			20000

  /* CHARGER regulator ops */
  /* CHARGER regulator uses two bits for enabling */
  static int max77693_chg_is_enabled(struct regulator_dev *rdev)
  {
  	int ret;

  	unsigned int val;

  	ret = regmap_read(rdev->regmap, rdev->desc->enable_reg, &val);

  	if (ret)
  		return ret;
  
  	return (val & rdev->desc->enable_mask) == rdev->desc->enable_mask;
  }
  
  /*
   * CHARGER regulator - Min : 20mA, Max : 2580mA, step : 20mA
   * 0x00, 0x01, 0x2, 0x03	= 60 mA
   * 0x04 ~ 0x7E			= (60 + (X - 3) * 20) mA
   */
  static int max77693_chg_get_current_limit(struct regulator_dev *rdev)
  {
  	unsigned int chg_min_uA = rdev->constraints->min_uA;
  	unsigned int chg_max_uA = rdev->constraints->max_uA;

  	unsigned int reg, sel;

  	unsigned int val;
  	int ret;

  	ret = regmap_read(rdev->regmap, MAX77693_CHG_REG_CHG_CNFG_09, &reg);

  	if (ret < 0)
  		return ret;
  
  	sel = reg & CHG_CNFG_09_CHGIN_ILIM_MASK;
  
  	/* the first four codes for charger current are all 60mA */
  	if (sel <= 3)
  		sel = 0;
  	else
  		sel -= 3;
  
  	val = chg_min_uA + CHGIN_ILIM_STEP_20mA * sel;
  	if (val > chg_max_uA)
  		return -EINVAL;
  
  	return val;
  }
  
  static int max77693_chg_set_current_limit(struct regulator_dev *rdev,
  						int min_uA, int max_uA)
  {
  	unsigned int chg_min_uA = rdev->constraints->min_uA;
  	int sel = 0;
  
  	while (chg_min_uA + CHGIN_ILIM_STEP_20mA * sel < min_uA)
  		sel++;

  	if (chg_min_uA + CHGIN_ILIM_STEP_20mA * sel > max_uA)

  		return -EINVAL;
  
  	/* the first four codes for charger current are all 60mA */
  	sel += 3;

  	return regmap_write(rdev->regmap,

  				MAX77693_CHG_REG_CHG_CNFG_09, sel);
  }
  /* end of CHARGER regulator ops */
  
  static const unsigned int max77693_safeout_table[] = {
  	4850000,
  	4900000,
  	4950000,
  	3300000,
  };
  
  static struct regulator_ops max77693_safeout_ops = {
  	.list_voltage		= regulator_list_voltage_table,
  	.is_enabled		= regulator_is_enabled_regmap,
  	.enable			= regulator_enable_regmap,
  	.disable		= regulator_disable_regmap,
  	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
  	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
  };
  
  static struct regulator_ops max77693_charger_ops = {
  	.is_enabled		= max77693_chg_is_enabled,
  	.enable			= regulator_enable_regmap,
  	.disable		= regulator_disable_regmap,
  	.get_current_limit	= max77693_chg_get_current_limit,
  	.set_current_limit	= max77693_chg_set_current_limit,
  };
  
  #define regulator_desc_esafeout(_num)	{			\
  	.name		= "ESAFEOUT"#_num,			\
  	.id		= MAX77693_ESAFEOUT##_num,		\
  	.n_voltages	= 4,					\
  	.ops		= &max77693_safeout_ops,		\
  	.type		= REGULATOR_VOLTAGE,			\

  	.owner		= THIS_MODULE,				\

  	.volt_table	= max77693_safeout_table,		\
  	.vsel_reg	= MAX77693_CHG_REG_SAFEOUT_CTRL,	\
  	.vsel_mask	= SAFEOUT_CTRL_SAFEOUT##_num##_MASK,	\
  	.enable_reg	= MAX77693_CHG_REG_SAFEOUT_CTRL,	\
  	.enable_mask	= SAFEOUT_CTRL_ENSAFEOUT##_num##_MASK ,	\
  }
  
  static struct regulator_desc regulators[] = {
  	regulator_desc_esafeout(1),
  	regulator_desc_esafeout(2),
  	{
  		.name = "CHARGER",
  		.id = MAX77693_CHARGER,
  		.ops = &max77693_charger_ops,
  		.type = REGULATOR_CURRENT,
  		.owner = THIS_MODULE,
  		.enable_reg = MAX77693_CHG_REG_CHG_CNFG_00,
  		.enable_mask = CHG_CNFG_00_CHG_MASK |
  				CHG_CNFG_00_BUCK_MASK,
  	},
  };
  
  #ifdef CONFIG_OF
  static int max77693_pmic_dt_parse_rdata(struct device *dev,
  					struct max77693_regulator_data **rdata)
  {
  	struct device_node *np;
  	struct of_regulator_match *rmatch;
  	struct max77693_regulator_data *tmp;
  	int i, matched = 0;

  	np = of_get_child_by_name(dev->parent->of_node, "regulators");

  	if (!np)
  		return -EINVAL;
  
  	rmatch = devm_kzalloc(dev,
  		 sizeof(*rmatch) * ARRAY_SIZE(regulators), GFP_KERNEL);

  	if (!rmatch) {
  		of_node_put(np);

  		return -ENOMEM;

  	}

  
  	for (i = 0; i < ARRAY_SIZE(regulators); i++)
  		rmatch[i].name = regulators[i].name;
  
  	matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(regulators));

  	of_node_put(np);

  	if (matched <= 0)
  		return matched;
  	*rdata = devm_kzalloc(dev, sizeof(**rdata) * matched, GFP_KERNEL);
  	if (!(*rdata))
  		return -ENOMEM;
  
  	tmp = *rdata;

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

  		tmp->initdata = rmatch[i].init_data;
  		tmp->of_node = rmatch[i].of_node;
  		tmp->id = regulators[i].id;
  		tmp++;
  	}
  
  	return matched;
  }
  #else
  static int max77693_pmic_dt_parse_rdata(struct device *dev,
  					struct max77693_regulator_data **rdata)
  {
  	return 0;
  }
  #endif /* CONFIG_OF */
  
  static int max77693_pmic_init_rdata(struct device *dev,
  				    struct max77693_regulator_data **rdata)
  {
  	struct max77693_platform_data *pdata;
  	int num_regulators = 0;
  
  	pdata = dev_get_platdata(dev->parent);
  	if (pdata) {
  		*rdata = pdata->regulators;
  		num_regulators = pdata->num_regulators;
  	}
  
  	if (!(*rdata) && dev->parent->of_node)
  		num_regulators = max77693_pmic_dt_parse_rdata(dev, rdata);
  
  	return num_regulators;
  }
  
  static int max77693_pmic_probe(struct platform_device *pdev)
  {
  	struct max77693_dev *iodev = dev_get_drvdata(pdev->dev.parent);

  	struct max77693_regulator_data *rdata = NULL;

  	int num_rdata, i;

  	struct regulator_config config = { };

  
  	num_rdata = max77693_pmic_init_rdata(&pdev->dev, &rdata);
  	if (!rdata || num_rdata <= 0) {
  		dev_err(&pdev->dev, "No init data supplied.
  ");
  		return -ENODEV;
  	}

  	config.dev = &pdev->dev;
  	config.regmap = iodev->regmap;

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

  		int id = rdata[i].id;

  		struct regulator_dev *rdev;

  
  		config.init_data = rdata[i].initdata;
  		config.of_node = rdata[i].of_node;

  		rdev = devm_regulator_register(&pdev->dev,

  						&regulators[id], &config);

  		if (IS_ERR(rdev)) {
  			dev_err(&pdev->dev,

  				"Failed to initialize regulator-%d
  ", id);

  			return PTR_ERR(rdev);

  		}
  	}
  
  	return 0;

  }
  
  static const struct platform_device_id max77693_pmic_id[] = {
  	{"max77693-pmic", 0},
  	{},
  };
  
  MODULE_DEVICE_TABLE(platform, max77693_pmic_id);
  
  static struct platform_driver max77693_pmic_driver = {
  	.driver = {
  		   .name = "max77693-pmic",
  		   .owner = THIS_MODULE,
  		   },
  	.probe = max77693_pmic_probe,

  	.id_table = max77693_pmic_id,
  };
  
  module_platform_driver(max77693_pmic_driver);
  
  MODULE_DESCRIPTION("MAXIM MAX77693 regulator driver");
  MODULE_AUTHOR("Jonghwa Lee <jonghwa3.lee@samsung.com>");
  MODULE_LICENSE("GPL");