// SPDX-License-Identifier: GPL-2.0+
  //
  // max77693.c - Regulator driver for the Maxim 77693 and 77843
  //
  // Copyright (C) 2013-2015 Samsung Electronics
  // Jonghwa Lee <jonghwa3.lee@samsung.com>
  // Krzysztof Kozlowski <krzk@kernel.org>
  //
  // 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-common.h>

  #include <linux/mfd/max77693-private.h>

  #include <linux/mfd/max77843-private.h>

  #include <linux/regulator/of_regulator.h>

  #include <linux/regmap.h>

  /*
   * ID for MAX77843 regulators.
   * There is no need for such for MAX77693.
   */
  enum max77843_regulator_type {
  	MAX77843_SAFEOUT1 = 0,
  	MAX77843_SAFEOUT2,
  	MAX77843_CHARGER,
  
  	MAX77843_NUM,
  };
  
  /* Register differences between chargers: MAX77693 and MAX77843 */

  struct chg_reg_data {
  	unsigned int linear_reg;
  	unsigned int linear_mask;
  	unsigned int uA_step;
  	unsigned int min_sel;
  };

  /*

   * MAX77693 CHARGER regulator - Min : 20mA, Max : 2580mA, step : 20mA

   * 0x00, 0x01, 0x2, 0x03	= 60 mA
   * 0x04 ~ 0x7E			= (60 + (X - 3) * 20) mA

   * Actually for MAX77693 the driver manipulates the maximum input current,
   * not the fast charge current (output). This should be fixed.
   *
   * On MAX77843 the calculation formula is the same (except values).
   * Fortunately it properly manipulates the fast charge current.

   */
  static int max77693_chg_get_current_limit(struct regulator_dev *rdev)
  {

  	const struct chg_reg_data *reg_data = rdev_get_drvdata(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, reg_data->linear_reg, &reg);

  	if (ret < 0)
  		return ret;

  	sel = reg & reg_data->linear_mask;

  
  	/* the first four codes for charger current are all 60mA */

  	if (sel <= reg_data->min_sel)

  		sel = 0;
  	else

  		sel -= reg_data->min_sel;

  	val = chg_min_uA + reg_data->uA_step * 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)
  {

  	const struct chg_reg_data *reg_data = rdev_get_drvdata(rdev);

  	unsigned int chg_min_uA = rdev->constraints->min_uA;
  	int sel = 0;

  	while (chg_min_uA + reg_data->uA_step * sel < min_uA)

  		sel++;

  	if (chg_min_uA + reg_data->uA_step * sel > max_uA)

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

  	sel += reg_data->min_sel;

  	return regmap_write(rdev->regmap, reg_data->linear_reg, sel);

  }
  /* end of CHARGER regulator ops */

  /* Returns regmap suitable for given regulator on chosen device */
  static struct regmap *max77693_get_regmap(enum max77693_types type,
  					  struct max77693_dev *max77693,
  					  int reg_id)
  {
  	if (type == TYPE_MAX77693)
  		return max77693->regmap;
  
  	/* Else: TYPE_MAX77843 */
  	switch (reg_id) {
  	case MAX77843_SAFEOUT1:
  	case MAX77843_SAFEOUT2:
  		return max77693->regmap;
  	case MAX77843_CHARGER:
  		return max77693->regmap_chg;
  	default:
  		return max77693->regmap;
  	}
  }

  static const unsigned int max77693_safeout_table[] = {
  	4850000,
  	4900000,
  	4950000,
  	3300000,
  };

  static const 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 const struct regulator_ops max77693_charger_ops = {

  	.is_enabled		= regulator_is_enabled_regmap,

  	.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 max77693_regulator_desc_esafeout(_num)	{		\

  	.name		= "ESAFEOUT"#_num,			\
  	.id		= MAX77693_ESAFEOUT##_num,		\

  	.of_match	= of_match_ptr("ESAFEOUT"#_num),	\
  	.regulators_node	= of_match_ptr("regulators"),	\

  	.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 const struct regulator_desc max77693_supported_regulators[] = {
  	max77693_regulator_desc_esafeout(1),
  	max77693_regulator_desc_esafeout(2),

  	{
  		.name = "CHARGER",
  		.id = MAX77693_CHARGER,

  		.of_match = of_match_ptr("CHARGER"),
  		.regulators_node = of_match_ptr("regulators"),

  		.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,

  		.enable_val = CHG_CNFG_00_CHG_MASK | CHG_CNFG_00_BUCK_MASK,

  	},
  };

  static const struct chg_reg_data max77693_chg_reg_data = {
  	.linear_reg	= MAX77693_CHG_REG_CHG_CNFG_09,
  	.linear_mask	= CHG_CNFG_09_CHGIN_ILIM_MASK,
  	.uA_step	= 20000,
  	.min_sel	= 3,
  };

  #define	max77843_regulator_desc_esafeout(num)	{			\
  	.name		= "SAFEOUT" # num,				\
  	.id		= MAX77843_SAFEOUT ## num,			\
  	.ops		= &max77693_safeout_ops,			\
  	.of_match	= of_match_ptr("SAFEOUT" # num),		\
  	.regulators_node = of_match_ptr("regulators"),			\
  	.type		= REGULATOR_VOLTAGE,				\
  	.owner		= THIS_MODULE,					\
  	.n_voltages	= ARRAY_SIZE(max77693_safeout_table),		\
  	.volt_table	= max77693_safeout_table,			\
  	.enable_reg	= MAX77843_SYS_REG_SAFEOUTCTRL,			\
  	.enable_mask	= MAX77843_REG_SAFEOUTCTRL_ENSAFEOUT ## num,	\
  	.vsel_reg	= MAX77843_SYS_REG_SAFEOUTCTRL,			\
  	.vsel_mask	= MAX77843_REG_SAFEOUTCTRL_SAFEOUT ## num ## _MASK, \
  }
  
  static const struct regulator_desc max77843_supported_regulators[] = {
  	[MAX77843_SAFEOUT1] = max77843_regulator_desc_esafeout(1),
  	[MAX77843_SAFEOUT2] = max77843_regulator_desc_esafeout(2),
  	[MAX77843_CHARGER] = {
  		.name		= "CHARGER",
  		.id		= MAX77843_CHARGER,
  		.ops		= &max77693_charger_ops,
  		.of_match	= of_match_ptr("CHARGER"),
  		.regulators_node = of_match_ptr("regulators"),
  		.type		= REGULATOR_CURRENT,
  		.owner		= THIS_MODULE,
  		.enable_reg	= MAX77843_CHG_REG_CHG_CNFG_00,
  		.enable_mask	= MAX77843_CHG_MASK,
  		.enable_val	= MAX77843_CHG_MASK,
  	},
  };
  
  static const struct chg_reg_data max77843_chg_reg_data = {
  	.linear_reg	= MAX77843_CHG_REG_CHG_CNFG_02,
  	.linear_mask	= MAX77843_CHG_FAST_CHG_CURRENT_MASK,
  	.uA_step	= MAX77843_CHG_FAST_CHG_CURRENT_STEP,
  	.min_sel	= 2,
  };

  static int max77693_pmic_probe(struct platform_device *pdev)
  {

  	enum max77693_types type = platform_get_device_id(pdev)->driver_data;

  	struct max77693_dev *iodev = dev_get_drvdata(pdev->dev.parent);

  	const struct regulator_desc *regulators;
  	unsigned int regulators_size;

  	int i;

  	struct regulator_config config = { };

  	config.dev = iodev->dev;

  	switch (type) {
  	case TYPE_MAX77693:
  		regulators = max77693_supported_regulators;
  		regulators_size = ARRAY_SIZE(max77693_supported_regulators);
  		config.driver_data = (void *)&max77693_chg_reg_data;
  		break;
  	case TYPE_MAX77843:
  		regulators = max77843_supported_regulators;
  		regulators_size = ARRAY_SIZE(max77843_supported_regulators);
  		config.driver_data = (void *)&max77843_chg_reg_data;
  		break;
  	default:
  		dev_err(&pdev->dev, "Unsupported device type: %u
  ", type);
  		return -ENODEV;
  	}
  
  	for (i = 0; i < regulators_size; i++) {

  		struct regulator_dev *rdev;

  		config.regmap = max77693_get_regmap(type, iodev,
  						    regulators[i].id);

  		rdev = devm_regulator_register(&pdev->dev,

  						&regulators[i], &config);

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

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

  			return PTR_ERR(rdev);

  		}
  	}
  
  	return 0;

  }
  
  static const struct platform_device_id max77693_pmic_id[] = {

  	{ "max77693-pmic", TYPE_MAX77693 },

  	{ "max77843-regulator", TYPE_MAX77843 },

  	{},
  };
  
  MODULE_DEVICE_TABLE(platform, max77693_pmic_id);
  
  static struct platform_driver max77693_pmic_driver = {
  	.driver = {
  		   .name = "max77693-pmic",

  		   },
  	.probe = max77693_pmic_probe,

  	.id_table = max77693_pmic_id,
  };

  static int __init max77693_pmic_init(void)
  {
  	return platform_driver_register(&max77693_pmic_driver);
  }
  subsys_initcall(max77693_pmic_init);
  
  static void __exit max77693_pmic_cleanup(void)
  {
  	platform_driver_unregister(&max77693_pmic_driver);
  }
  module_exit(max77693_pmic_cleanup);

  MODULE_DESCRIPTION("MAXIM 77693/77843 regulator driver");

  MODULE_AUTHOR("Jonghwa Lee <jonghwa3.lee@samsung.com>");

  MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");

  MODULE_LICENSE("GPL");