// SPDX-License-Identifier: GPL-2.0+
  //
  // Copyright (c) 2013 Samsung Electronics Co., Ltd
  //		http://www.samsung.com

  
  #include <linux/bug.h>
  #include <linux/err.h>
  #include <linux/gpio.h>
  #include <linux/slab.h>
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/regmap.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/samsung/core.h>
  #include <linux/mfd/samsung/s2mpa01.h>

  struct s2mpa01_info {
  	int ramp_delay24;
  	int ramp_delay3;
  	int ramp_delay5;
  	int ramp_delay16;
  	int ramp_delay7;
  	int ramp_delay8910;
  };
  
  static int get_ramp_delay(int ramp_delay)
  {
  	unsigned char cnt = 0;
  
  	ramp_delay /= 6250;
  
  	while (true) {
  		ramp_delay = ramp_delay >> 1;
  		if (ramp_delay == 0)
  			break;
  		cnt++;
  	}
  
  	if (cnt > 3)
  		cnt = 3;
  
  	return cnt;
  }
  
  static int s2mpa01_regulator_set_voltage_time_sel(struct regulator_dev *rdev,
  				   unsigned int old_selector,
  				   unsigned int new_selector)
  {
  	struct s2mpa01_info *s2mpa01 = rdev_get_drvdata(rdev);
  	unsigned int ramp_delay = 0;
  	int old_volt, new_volt;

  	switch (rdev_get_id(rdev)) {

  	case S2MPA01_BUCK2:
  	case S2MPA01_BUCK4:
  		ramp_delay = s2mpa01->ramp_delay24;
  		break;
  	case S2MPA01_BUCK3:
  		ramp_delay = s2mpa01->ramp_delay3;
  		break;
  	case S2MPA01_BUCK5:
  		ramp_delay = s2mpa01->ramp_delay5;
  		break;
  	case S2MPA01_BUCK1:
  	case S2MPA01_BUCK6:
  		ramp_delay = s2mpa01->ramp_delay16;
  		break;
  	case S2MPA01_BUCK7:
  		ramp_delay = s2mpa01->ramp_delay7;
  		break;
  	case S2MPA01_BUCK8:
  	case S2MPA01_BUCK9:
  	case S2MPA01_BUCK10:
  		ramp_delay = s2mpa01->ramp_delay8910;
  		break;
  	}
  
  	if (ramp_delay == 0)
  		ramp_delay = rdev->desc->ramp_delay;
  
  	old_volt = rdev->desc->min_uV + (rdev->desc->uV_step * old_selector);
  	new_volt = rdev->desc->min_uV + (rdev->desc->uV_step * new_selector);
  
  	return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
  }
  
  static int s2mpa01_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
  {
  	struct s2mpa01_info *s2mpa01 = rdev_get_drvdata(rdev);
  	unsigned int ramp_val, ramp_shift, ramp_reg = S2MPA01_REG_RAMP2;
  	unsigned int ramp_enable = 1, enable_shift = 0;
  	int ret;

  	switch (rdev_get_id(rdev)) {

  	case S2MPA01_BUCK1:
  		enable_shift = S2MPA01_BUCK1_RAMP_EN_SHIFT;
  		if (!ramp_delay) {
  			ramp_enable = 0;
  			break;
  		}
  
  		if (ramp_delay > s2mpa01->ramp_delay16)
  			s2mpa01->ramp_delay16 = ramp_delay;
  		else
  			ramp_delay = s2mpa01->ramp_delay16;
  
  		ramp_shift = S2MPA01_BUCK16_RAMP_SHIFT;

  		break;
  	case S2MPA01_BUCK2:
  		enable_shift = S2MPA01_BUCK2_RAMP_EN_SHIFT;
  		if (!ramp_delay) {
  			ramp_enable = 0;
  			break;
  		}
  
  		if (ramp_delay > s2mpa01->ramp_delay24)
  			s2mpa01->ramp_delay24 = ramp_delay;
  		else
  			ramp_delay = s2mpa01->ramp_delay24;
  
  		ramp_shift = S2MPA01_BUCK24_RAMP_SHIFT;
  		ramp_reg = S2MPA01_REG_RAMP1;
  		break;
  	case S2MPA01_BUCK3:
  		enable_shift = S2MPA01_BUCK3_RAMP_EN_SHIFT;
  		if (!ramp_delay) {
  			ramp_enable = 0;
  			break;
  		}
  
  		s2mpa01->ramp_delay3 = ramp_delay;
  		ramp_shift = S2MPA01_BUCK3_RAMP_SHIFT;
  		ramp_reg = S2MPA01_REG_RAMP1;
  		break;
  	case S2MPA01_BUCK4:
  		enable_shift = S2MPA01_BUCK4_RAMP_EN_SHIFT;
  		if (!ramp_delay) {
  			ramp_enable = 0;
  			break;
  		}
  
  		if (ramp_delay > s2mpa01->ramp_delay24)
  			s2mpa01->ramp_delay24 = ramp_delay;
  		else
  			ramp_delay = s2mpa01->ramp_delay24;
  
  		ramp_shift = S2MPA01_BUCK24_RAMP_SHIFT;
  		ramp_reg = S2MPA01_REG_RAMP1;
  		break;
  	case S2MPA01_BUCK5:
  		s2mpa01->ramp_delay5 = ramp_delay;
  		ramp_shift = S2MPA01_BUCK5_RAMP_SHIFT;
  		break;
  	case S2MPA01_BUCK6:
  		if (ramp_delay > s2mpa01->ramp_delay16)
  			s2mpa01->ramp_delay16 = ramp_delay;
  		else
  			ramp_delay = s2mpa01->ramp_delay16;
  
  		ramp_shift = S2MPA01_BUCK16_RAMP_SHIFT;
  		break;
  	case S2MPA01_BUCK7:
  		s2mpa01->ramp_delay7 = ramp_delay;
  		ramp_shift = S2MPA01_BUCK7_RAMP_SHIFT;
  		break;
  	case S2MPA01_BUCK8:
  	case S2MPA01_BUCK9:
  	case S2MPA01_BUCK10:
  		if (ramp_delay > s2mpa01->ramp_delay8910)
  			s2mpa01->ramp_delay8910 = ramp_delay;
  		else
  			ramp_delay = s2mpa01->ramp_delay8910;
  
  		ramp_shift = S2MPA01_BUCK8910_RAMP_SHIFT;
  		break;
  	default:
  		return 0;
  	}
  
  	if (!ramp_enable)
  		goto ramp_disable;

  	/* Ramp delay can be enabled/disabled only for buck[1234] */
  	if (rdev_get_id(rdev) >= S2MPA01_BUCK1 &&
  			rdev_get_id(rdev) <= S2MPA01_BUCK4) {
  		ret = regmap_update_bits(rdev->regmap, S2MPA01_REG_RAMP1,
  					 1 << enable_shift, 1 << enable_shift);
  		if (ret) {
  			dev_err(&rdev->dev, "failed to enable ramp rate
  ");
  			return ret;
  		}

  	}
  
  	ramp_val = get_ramp_delay(ramp_delay);
  
  	return regmap_update_bits(rdev->regmap, ramp_reg, 0x3 << ramp_shift,
  				  ramp_val << ramp_shift);
  
  ramp_disable:
  	return regmap_update_bits(rdev->regmap, S2MPA01_REG_RAMP1,
  				  1 << enable_shift, 0);
  }

  static const struct regulator_ops s2mpa01_ldo_ops = {

  	.list_voltage		= regulator_list_voltage_linear,
  	.map_voltage		= regulator_map_voltage_linear,
  	.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,
  	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
  };

  static const struct regulator_ops s2mpa01_buck_ops = {

  	.list_voltage		= regulator_list_voltage_linear,
  	.map_voltage		= regulator_map_voltage_linear,
  	.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,
  	.set_voltage_time_sel	= s2mpa01_regulator_set_voltage_time_sel,
  	.set_ramp_delay		= s2mpa01_set_ramp_delay,
  };

  #define regulator_desc_ldo(num, step) {			\

  	.name		= "LDO"#num,			\

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

  	.id		= S2MPA01_LDO##num,		\
  	.ops		= &s2mpa01_ldo_ops,		\
  	.type		= REGULATOR_VOLTAGE,		\
  	.owner		= THIS_MODULE,			\

  	.min_uV		= MIN_800_MV,			\

  	.uV_step	= step,				\

  	.n_voltages	= S2MPA01_LDO_N_VOLTAGES,	\
  	.vsel_reg	= S2MPA01_REG_L1CTRL + num - 1,	\
  	.vsel_mask	= S2MPA01_LDO_VSEL_MASK,	\
  	.enable_reg	= S2MPA01_REG_L1CTRL + num - 1,	\
  	.enable_mask	= S2MPA01_ENABLE_MASK		\
  }
  
  #define regulator_desc_buck1_4(num)	{			\
  	.name		= "BUCK"#num,				\

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

  	.id		= S2MPA01_BUCK##num,			\
  	.ops		= &s2mpa01_buck_ops,			\
  	.type		= REGULATOR_VOLTAGE,			\
  	.owner		= THIS_MODULE,				\

  	.min_uV		= MIN_600_MV,				\
  	.uV_step	= STEP_6_25_MV,				\

  	.n_voltages	= S2MPA01_BUCK_N_VOLTAGES,		\
  	.ramp_delay	= S2MPA01_RAMP_DELAY,			\
  	.vsel_reg	= S2MPA01_REG_B1CTRL2 + (num - 1) * 2,	\
  	.vsel_mask	= S2MPA01_BUCK_VSEL_MASK,		\
  	.enable_reg	= S2MPA01_REG_B1CTRL1 + (num - 1) * 2,	\
  	.enable_mask	= S2MPA01_ENABLE_MASK			\
  }
  
  #define regulator_desc_buck5	{				\
  	.name		= "BUCK5",				\

  	.of_match	= of_match_ptr("BUCK5"),		\
  	.regulators_node = of_match_ptr("regulators"),		\

  	.id		= S2MPA01_BUCK5,			\
  	.ops		= &s2mpa01_buck_ops,			\
  	.type		= REGULATOR_VOLTAGE,			\
  	.owner		= THIS_MODULE,				\

  	.min_uV		= MIN_800_MV,				\
  	.uV_step	= STEP_6_25_MV,				\

  	.n_voltages	= S2MPA01_BUCK_N_VOLTAGES,		\
  	.ramp_delay	= S2MPA01_RAMP_DELAY,			\
  	.vsel_reg	= S2MPA01_REG_B5CTRL2,			\
  	.vsel_mask	= S2MPA01_BUCK_VSEL_MASK,		\
  	.enable_reg	= S2MPA01_REG_B5CTRL1,			\
  	.enable_mask	= S2MPA01_ENABLE_MASK			\
  }

  #define regulator_desc_buck6_10(num, min, step) {			\

  	.name		= "BUCK"#num,				\

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

  	.id		= S2MPA01_BUCK##num,			\
  	.ops		= &s2mpa01_buck_ops,			\
  	.type		= REGULATOR_VOLTAGE,			\
  	.owner		= THIS_MODULE,				\

  	.min_uV		= min,					\
  	.uV_step	= step,					\

  	.n_voltages	= S2MPA01_BUCK_N_VOLTAGES,		\
  	.ramp_delay	= S2MPA01_RAMP_DELAY,			\
  	.vsel_reg	= S2MPA01_REG_B6CTRL2 + (num - 6) * 2,	\
  	.vsel_mask	= S2MPA01_BUCK_VSEL_MASK,		\
  	.enable_reg	= S2MPA01_REG_B6CTRL1 + (num - 6) * 2,	\
  	.enable_mask	= S2MPA01_ENABLE_MASK			\
  }

  static const struct regulator_desc regulators[] = {

  	regulator_desc_ldo(1, STEP_25_MV),
  	regulator_desc_ldo(2, STEP_50_MV),
  	regulator_desc_ldo(3, STEP_50_MV),
  	regulator_desc_ldo(4, STEP_50_MV),

  	regulator_desc_ldo(5, STEP_25_MV),

  	regulator_desc_ldo(6, STEP_25_MV),
  	regulator_desc_ldo(7, STEP_50_MV),
  	regulator_desc_ldo(8, STEP_50_MV),
  	regulator_desc_ldo(9, STEP_50_MV),
  	regulator_desc_ldo(10, STEP_50_MV),

  	regulator_desc_ldo(11, STEP_50_MV),

  	regulator_desc_ldo(12, STEP_50_MV),
  	regulator_desc_ldo(13, STEP_50_MV),
  	regulator_desc_ldo(14, STEP_50_MV),
  	regulator_desc_ldo(15, STEP_50_MV),
  	regulator_desc_ldo(16, STEP_50_MV),
  	regulator_desc_ldo(17, STEP_50_MV),
  	regulator_desc_ldo(18, STEP_50_MV),
  	regulator_desc_ldo(19, STEP_50_MV),
  	regulator_desc_ldo(20, STEP_50_MV),
  	regulator_desc_ldo(21, STEP_50_MV),

  	regulator_desc_ldo(22, STEP_50_MV),
  	regulator_desc_ldo(23, STEP_50_MV),

  	regulator_desc_ldo(24, STEP_50_MV),
  	regulator_desc_ldo(25, STEP_50_MV),

  	regulator_desc_ldo(26, STEP_25_MV),

  	regulator_desc_buck1_4(1),
  	regulator_desc_buck1_4(2),
  	regulator_desc_buck1_4(3),
  	regulator_desc_buck1_4(4),
  	regulator_desc_buck5,

  	regulator_desc_buck6_10(6, MIN_600_MV, STEP_6_25_MV),
  	regulator_desc_buck6_10(7, MIN_600_MV, STEP_6_25_MV),
  	regulator_desc_buck6_10(8, MIN_800_MV, STEP_12_5_MV),
  	regulator_desc_buck6_10(9, MIN_1500_MV, STEP_12_5_MV),
  	regulator_desc_buck6_10(10, MIN_1000_MV, STEP_12_5_MV),

  };
  
  static int s2mpa01_pmic_probe(struct platform_device *pdev)
  {
  	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
  	struct sec_platform_data *pdata = dev_get_platdata(iodev->dev);

  	struct regulator_config config = { };
  	struct s2mpa01_info *s2mpa01;
  	int i;
  
  	s2mpa01 = devm_kzalloc(&pdev->dev, sizeof(*s2mpa01), GFP_KERNEL);
  	if (!s2mpa01)
  		return -ENOMEM;

  	config.dev = iodev->dev;

  	config.regmap = iodev->regmap_pmic;
  	config.driver_data = s2mpa01;
  
  	for (i = 0; i < S2MPA01_REGULATOR_MAX; i++) {
  		struct regulator_dev *rdev;

  		if (pdata)
  			config.init_data = pdata->regulators[i].initdata;

  
  		rdev = devm_regulator_register(&pdev->dev,
  						&regulators[i], &config);
  		if (IS_ERR(rdev)) {
  			dev_err(&pdev->dev, "regulator init failed for %d
  ",
  				i);
  			return PTR_ERR(rdev);
  		}
  	}
  
  	return 0;
  }
  
  static const struct platform_device_id s2mpa01_pmic_id[] = {
  	{ "s2mpa01-pmic", 0},
  	{ },
  };
  MODULE_DEVICE_TABLE(platform, s2mpa01_pmic_id);
  
  static struct platform_driver s2mpa01_pmic_driver = {
  	.driver = {
  		.name = "s2mpa01-pmic",

  	},
  	.probe = s2mpa01_pmic_probe,
  	.id_table = s2mpa01_pmic_id,
  };
  
  module_platform_driver(s2mpa01_pmic_driver);
  
  /* Module information */
  MODULE_AUTHOR("Sangbeom Kim <sbkim73@samsung.com>");
  MODULE_AUTHOR("Sachin Kamat <sachin.kamat@samsung.com>");

  MODULE_DESCRIPTION("Samsung S2MPA01 Regulator Driver");

  MODULE_LICENSE("GPL");