/*
   * Regulator driver for TI TPS6586x
   *
   * Copyright (C) 2010 Compulab Ltd.
   * Author: Mike Rapoport <mike@compulab.co.il>
   *
   * Based on da903x
   * Copyright (C) 2006-2008 Marvell International Ltd.
   * Copyright (C) 2008 Compulab Ltd.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */

  #include <linux/kernel.h>

  #include <linux/module.h>

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

  #include <linux/of.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/tps6586x.h>
  
  /* supply control and voltage setting  */
  #define TPS6586X_SUPPLYENA	0x10
  #define TPS6586X_SUPPLYENB	0x11
  #define TPS6586X_SUPPLYENC	0x12
  #define TPS6586X_SUPPLYEND	0x13
  #define TPS6586X_SUPPLYENE	0x14
  #define TPS6586X_VCC1		0x20
  #define TPS6586X_VCC2		0x21
  #define TPS6586X_SM1V1		0x23
  #define TPS6586X_SM1V2		0x24
  #define TPS6586X_SM1SL		0x25
  #define TPS6586X_SM0V1		0x26
  #define TPS6586X_SM0V2		0x27
  #define TPS6586X_SM0SL		0x28
  #define TPS6586X_LDO2AV1	0x29
  #define TPS6586X_LDO2AV2	0x2A
  #define TPS6586X_LDO2BV1	0x2F
  #define TPS6586X_LDO2BV2	0x30
  #define TPS6586X_LDO4V1		0x32
  #define TPS6586X_LDO4V2		0x33
  
  /* converter settings  */
  #define TPS6586X_SUPPLYV1	0x41
  #define TPS6586X_SUPPLYV2	0x42
  #define TPS6586X_SUPPLYV3	0x43
  #define TPS6586X_SUPPLYV4	0x44
  #define TPS6586X_SUPPLYV5	0x45
  #define TPS6586X_SUPPLYV6	0x46
  #define TPS6586X_SMODE1		0x47
  #define TPS6586X_SMODE2		0x48
  
  struct tps6586x_regulator {
  	struct regulator_desc desc;

  	int enable_bit[2];
  	int enable_reg[2];

  };
  
  static inline struct device *to_tps6586x_dev(struct regulator_dev *rdev)
  {

  	return rdev_get_dev(rdev)->parent;

  }

  static struct regulator_ops tps6586x_regulator_ops = {

  	.list_voltage = regulator_list_voltage_table,

  	.map_voltage = regulator_map_voltage_ascend,

  	.get_voltage_sel = regulator_get_voltage_sel_regmap,

  	.set_voltage_sel = regulator_set_voltage_sel_regmap,

  	.is_enabled = regulator_is_enabled_regmap,
  	.enable = regulator_enable_regmap,
  	.disable = regulator_disable_regmap,

  };

  static struct regulator_ops tps6586x_sys_regulator_ops = {

  };

  static const unsigned int tps6586x_ldo0_voltages[] = {
  	1200000, 1500000, 1800000, 2500000, 2700000, 2850000, 3100000, 3300000,
  };
  
  static const unsigned int tps6586x_ldo4_voltages[] = {
  	1700000, 1725000, 1750000, 1775000, 1800000, 1825000, 1850000, 1875000,
  	1900000, 1925000, 1950000, 1975000, 2000000, 2025000, 2050000, 2075000,
  	2100000, 2125000, 2150000, 2175000, 2200000, 2225000, 2250000, 2275000,
  	2300000, 2325000, 2350000, 2375000, 2400000, 2425000, 2450000, 2475000,

  };

  static const unsigned int tps6586x_ldo_voltages[] = {
  	1250000, 1500000, 1800000, 2500000, 2700000, 2850000, 3100000, 3300000,

  };

  static const unsigned int tps6586x_sm2_voltages[] = {
  	3000000, 3050000, 3100000, 3150000, 3200000, 3250000, 3300000, 3350000,
  	3400000, 3450000, 3500000, 3550000, 3600000, 3650000, 3700000, 3750000,
  	3800000, 3850000, 3900000, 3950000, 4000000, 4050000, 4100000, 4150000,
  	4200000, 4250000, 4300000, 4350000, 4400000, 4450000, 4500000, 4550000,

  };

  static const unsigned int tps6586x_dvm_voltages[] = {
  	 725000,  750000,  775000,  800000,  825000,  850000,  875000,  900000,
  	 925000,  950000,  975000, 1000000, 1025000, 1050000, 1075000, 1100000,
  	1125000, 1150000, 1175000, 1200000, 1225000, 1250000, 1275000, 1300000,
  	1325000, 1350000, 1375000, 1400000, 1425000, 1450000, 1475000, 1500000,

  };

  #define TPS6586X_REGULATOR(_id, _pin_name, vdata, vreg, shift, nbits,	\

  			   ereg0, ebit0, ereg1, ebit1, goreg, gobit)	\

  	.desc	= {							\

  		.supply_name = _pin_name,				\

  		.name	= "REG-" #_id,					\

  		.ops	= &tps6586x_regulator_ops,			\

  		.type	= REGULATOR_VOLTAGE,				\
  		.id	= TPS6586X_ID_##_id,				\
  		.n_voltages = ARRAY_SIZE(tps6586x_##vdata##_voltages),	\

  		.volt_table = tps6586x_##vdata##_voltages,		\

  		.owner	= THIS_MODULE,					\

  		.enable_reg = TPS6586X_SUPPLY##ereg0,			\
  		.enable_mask = 1 << (ebit0),				\
  		.vsel_reg = TPS6586X_##vreg,				\
  		.vsel_mask = ((1 << (nbits)) - 1) << (shift),		\

  		.apply_reg = (goreg),				\
  		.apply_bit = (gobit),				\

  	},								\

  	.enable_reg[0]	= TPS6586X_SUPPLY##ereg0,			\
  	.enable_bit[0]	= (ebit0),					\
  	.enable_reg[1]	= TPS6586X_SUPPLY##ereg1,			\

  	.enable_bit[1]	= (ebit1),

  #define TPS6586X_LDO(_id, _pname, vdata, vreg, shift, nbits,		\

  		     ereg0, ebit0, ereg1, ebit1)			\

  {									\

  	TPS6586X_REGULATOR(_id, _pname, vdata, vreg, shift, nbits,	\

  			   ereg0, ebit0, ereg1, ebit1, 0, 0)		\

  }

  #define TPS6586X_DVM(_id, _pname, vdata, vreg, shift, nbits,		\

  		     ereg0, ebit0, ereg1, ebit1, goreg, gobit)		\

  {									\

  	TPS6586X_REGULATOR(_id, _pname, vdata, vreg, shift, nbits,	\

  			   ereg0, ebit0, ereg1, ebit1, goreg, gobit)	\

  }

  #define TPS6586X_SYS_REGULATOR()					\
  {									\
  	.desc	= {							\
  		.supply_name = "sys",					\
  		.name	= "REG-SYS",					\
  		.ops	= &tps6586x_sys_regulator_ops,			\
  		.type	= REGULATOR_VOLTAGE,				\
  		.id	= TPS6586X_ID_SYS,				\
  		.owner	= THIS_MODULE,					\
  	},								\
  }

  static struct tps6586x_regulator tps6586x_regulator[] = {

  	TPS6586X_SYS_REGULATOR(),

  	TPS6586X_LDO(LDO_0, "vinldo01", ldo0, SUPPLYV1, 5, 3, ENC, 0, END, 0),
  	TPS6586X_LDO(LDO_3, "vinldo23", ldo, SUPPLYV4, 0, 3, ENC, 2, END, 2),

  	TPS6586X_LDO(LDO_5, "REG-SYS", ldo, SUPPLYV6, 0, 3, ENE, 6, ENE, 6),

  	TPS6586X_LDO(LDO_6, "vinldo678", ldo, SUPPLYV3, 0, 3, ENC, 4, END, 4),
  	TPS6586X_LDO(LDO_7, "vinldo678", ldo, SUPPLYV3, 3, 3, ENC, 5, END, 5),
  	TPS6586X_LDO(LDO_8, "vinldo678", ldo, SUPPLYV2, 5, 3, ENC, 6, END, 6),
  	TPS6586X_LDO(LDO_9, "vinldo9", ldo, SUPPLYV6, 3, 3, ENE, 7, ENE, 7),

  	TPS6586X_LDO(LDO_RTC, "REG-SYS", ldo, SUPPLYV4, 3, 3, V4, 7, V4, 7),

  	TPS6586X_LDO(LDO_1, "vinldo01", dvm, SUPPLYV1, 0, 5, ENC, 1, END, 1),

  	TPS6586X_LDO(SM_2, "vin-sm2", sm2, SUPPLYV2, 0, 5, ENC, 7, END, 7),

  
  	TPS6586X_DVM(LDO_2, "vinldo23", dvm, LDO2BV1, 0, 5, ENA, 3,

  					ENB, 3, TPS6586X_VCC2, BIT(6)),

  	TPS6586X_DVM(LDO_4, "vinldo4", ldo4, LDO4V1, 0, 5, ENC, 3,

  					END, 3, TPS6586X_VCC1, BIT(6)),

  	TPS6586X_DVM(SM_0, "vin-sm0", dvm, SM0V1, 0, 5, ENA, 1,

  					ENB, 1, TPS6586X_VCC1, BIT(2)),

  	TPS6586X_DVM(SM_1, "vin-sm1", dvm, SM1V1, 0, 5, ENA, 0,

  					ENB, 0, TPS6586X_VCC1, BIT(0)),

  };
  
  /*
   * TPS6586X has 2 enable bits that are OR'ed to determine the actual
   * regulator state. Clearing one of this bits allows switching
   * regulator on and of with single register write.
   */
  static inline int tps6586x_regulator_preinit(struct device *parent,
  					     struct tps6586x_regulator *ri)
  {
  	uint8_t val1, val2;
  	int ret;

  	if (ri->enable_reg[0] == ri->enable_reg[1] &&
  	    ri->enable_bit[0] == ri->enable_bit[1])
  			return 0;

  	ret = tps6586x_read(parent, ri->enable_reg[0], &val1);
  	if (ret)
  		return ret;
  
  	ret = tps6586x_read(parent, ri->enable_reg[1], &val2);
  	if (ret)
  		return ret;

  	if (!(val2 & (1 << ri->enable_bit[1])))

  		return 0;
  
  	/*
  	 * The regulator is on, but it's enabled with the bit we don't
  	 * want to use, so we switch the enable bits
  	 */

  	if (!(val1 & (1 << ri->enable_bit[0]))) {

  		ret = tps6586x_set_bits(parent, ri->enable_reg[0],
  					1 << ri->enable_bit[0]);
  		if (ret)
  			return ret;
  	}
  
  	return tps6586x_clr_bits(parent, ri->enable_reg[1],
  				 1 << ri->enable_bit[1]);
  }

  static int tps6586x_regulator_set_slew_rate(struct platform_device *pdev,
  			int id, struct regulator_init_data *p)

  {
  	struct device *parent = pdev->dev.parent;

  	struct tps6586x_settings *setting = p->driver_data;
  	uint8_t reg;
  
  	if (setting == NULL)
  		return 0;
  
  	if (!(setting->slew_rate & TPS6586X_SLEW_RATE_SET))
  		return 0;
  
  	/* only SM0 and SM1 can have the slew rate settings */

  	switch (id) {

  	case TPS6586X_ID_SM_0:
  		reg = TPS6586X_SM0SL;
  		break;
  	case TPS6586X_ID_SM_1:
  		reg = TPS6586X_SM1SL;
  		break;
  	default:

  		dev_err(&pdev->dev, "Only SM0/SM1 can set slew rate
  ");

  		return -EINVAL;
  	}
  
  	return tps6586x_write(parent, reg,
  			setting->slew_rate & TPS6586X_SLEW_RATE_MASK);
  }

  static inline struct tps6586x_regulator *find_regulator_info(int id)
  {
  	struct tps6586x_regulator *ri;
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(tps6586x_regulator); i++) {
  		ri = &tps6586x_regulator[i];
  		if (ri->desc.id == id)
  			return ri;
  	}
  	return NULL;
  }

  #ifdef CONFIG_OF
  static struct of_regulator_match tps6586x_matches[] = {
  	{ .name = "sys",     .driver_data = (void *)TPS6586X_ID_SYS     },
  	{ .name = "sm0",     .driver_data = (void *)TPS6586X_ID_SM_0    },
  	{ .name = "sm1",     .driver_data = (void *)TPS6586X_ID_SM_1    },
  	{ .name = "sm2",     .driver_data = (void *)TPS6586X_ID_SM_2    },
  	{ .name = "ldo0",    .driver_data = (void *)TPS6586X_ID_LDO_0   },
  	{ .name = "ldo1",    .driver_data = (void *)TPS6586X_ID_LDO_1   },
  	{ .name = "ldo2",    .driver_data = (void *)TPS6586X_ID_LDO_2   },
  	{ .name = "ldo3",    .driver_data = (void *)TPS6586X_ID_LDO_3   },
  	{ .name = "ldo4",    .driver_data = (void *)TPS6586X_ID_LDO_4   },
  	{ .name = "ldo5",    .driver_data = (void *)TPS6586X_ID_LDO_5   },
  	{ .name = "ldo6",    .driver_data = (void *)TPS6586X_ID_LDO_6   },
  	{ .name = "ldo7",    .driver_data = (void *)TPS6586X_ID_LDO_7   },
  	{ .name = "ldo8",    .driver_data = (void *)TPS6586X_ID_LDO_8   },
  	{ .name = "ldo9",    .driver_data = (void *)TPS6586X_ID_LDO_9   },
  	{ .name = "ldo_rtc", .driver_data = (void *)TPS6586X_ID_LDO_RTC },
  };
  
  static struct tps6586x_platform_data *tps6586x_parse_regulator_dt(
  		struct platform_device *pdev,
  		struct of_regulator_match **tps6586x_reg_matches)
  {
  	const unsigned int num = ARRAY_SIZE(tps6586x_matches);
  	struct device_node *np = pdev->dev.parent->of_node;
  	struct device_node *regs;
  	const char *sys_rail = NULL;
  	unsigned int i;
  	struct tps6586x_platform_data *pdata;
  	int err;
  
  	regs = of_find_node_by_name(np, "regulators");
  	if (!regs) {
  		dev_err(&pdev->dev, "regulator node not found
  ");
  		return NULL;
  	}
  
  	err = of_regulator_match(&pdev->dev, regs, tps6586x_matches, num);

  	of_node_put(regs);

  	if (err < 0) {
  		dev_err(&pdev->dev, "Regulator match failed, e %d
  ", err);

  		return NULL;
  	}

  	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
  	if (!pdata) {
  		dev_err(&pdev->dev, "Memory alloction failed
  ");
  		return NULL;
  	}
  
  	for (i = 0; i < num; i++) {
  		int id;
  		if (!tps6586x_matches[i].init_data)
  			continue;
  
  		pdata->reg_init_data[i] = tps6586x_matches[i].init_data;
  		id = (int)tps6586x_matches[i].driver_data;
  		if (id == TPS6586X_ID_SYS)
  			sys_rail = pdata->reg_init_data[i]->constraints.name;
  
  		if ((id == TPS6586X_ID_LDO_5) || (id == TPS6586X_ID_LDO_RTC))
  			pdata->reg_init_data[i]->supply_regulator = sys_rail;
  	}
  	*tps6586x_reg_matches = tps6586x_matches;
  	return pdata;
  }
  #else
  static struct tps6586x_platform_data *tps6586x_parse_regulator_dt(
  		struct platform_device *pdev,
  		struct of_regulator_match **tps6586x_reg_matches)
  {
  	*tps6586x_reg_matches = NULL;
  	return NULL;
  }
  #endif

  static int tps6586x_regulator_probe(struct platform_device *pdev)

  {
  	struct tps6586x_regulator *ri = NULL;

  	struct regulator_config config = { };

  	struct regulator_dev **rdev;
  	struct regulator_init_data *reg_data;
  	struct tps6586x_platform_data *pdata;
  	struct of_regulator_match *tps6586x_reg_matches = NULL;
  	int id;

  	int err;

  	dev_dbg(&pdev->dev, "Probing regulator
  ");

  	pdata = dev_get_platdata(pdev->dev.parent);
  	if ((!pdata) && (pdev->dev.parent->of_node))
  		pdata = tps6586x_parse_regulator_dt(pdev,
  					&tps6586x_reg_matches);

  	if (!pdata) {
  		dev_err(&pdev->dev, "Platform data not available, exiting
  ");
  		return -ENODEV;
  	}

  	rdev = devm_kzalloc(&pdev->dev, TPS6586X_ID_MAX_REGULATOR *
  				sizeof(*rdev), GFP_KERNEL);
  	if (!rdev) {
  		dev_err(&pdev->dev, "Mmemory alloc failed
  ");
  		return -ENOMEM;
  	}

  	for (id = 0; id < TPS6586X_ID_MAX_REGULATOR; ++id) {
  		reg_data = pdata->reg_init_data[id];
  
  		ri = find_regulator_info(id);
  		if (!ri) {
  			dev_err(&pdev->dev, "invalid regulator ID specified
  ");
  			err = -EINVAL;
  			goto fail;
  		}
  
  		err = tps6586x_regulator_preinit(pdev->dev.parent, ri);
  		if (err) {
  			dev_err(&pdev->dev,
  				"regulator %d preinit failed, e %d
  ", id, err);
  			goto fail;
  		}
  
  		config.dev = pdev->dev.parent;
  		config.init_data = reg_data;
  		config.driver_data = ri;
  
  		if (tps6586x_reg_matches)
  			config.of_node = tps6586x_reg_matches[id].of_node;
  
  		rdev[id] = regulator_register(&ri->desc, &config);
  		if (IS_ERR(rdev[id])) {
  			dev_err(&pdev->dev, "failed to register regulator %s
  ",
  					ri->desc.name);
  			err = PTR_ERR(rdev[id]);
  			goto fail;
  		}
  
  		if (reg_data) {
  			err = tps6586x_regulator_set_slew_rate(pdev, id,
  					reg_data);
  			if (err < 0) {
  				dev_err(&pdev->dev,
  					"Slew rate config failed, e %d
  ", err);
  				regulator_unregister(rdev[id]);
  				goto fail;
  			}
  		}

  	}

  	platform_set_drvdata(pdev, rdev);

  	return 0;

  fail:
  	while (--id >= 0)
  		regulator_unregister(rdev[id]);
  	return err;

  }

  static int tps6586x_regulator_remove(struct platform_device *pdev)

  {

  	struct regulator_dev **rdev = platform_get_drvdata(pdev);
  	int id = TPS6586X_ID_MAX_REGULATOR;
  
  	while (--id >= 0)
  		regulator_unregister(rdev[id]);

  	return 0;
  }
  
  static struct platform_driver tps6586x_regulator_driver = {
  	.driver	= {

  		.name	= "tps6586x-regulator",

  		.owner	= THIS_MODULE,
  	},
  	.probe		= tps6586x_regulator_probe,

  	.remove		= tps6586x_regulator_remove,

  };
  
  static int __init tps6586x_regulator_init(void)
  {
  	return platform_driver_register(&tps6586x_regulator_driver);
  }
  subsys_initcall(tps6586x_regulator_init);
  
  static void __exit tps6586x_regulator_exit(void)
  {
  	platform_driver_unregister(&tps6586x_regulator_driver);
  }
  module_exit(tps6586x_regulator_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
  MODULE_DESCRIPTION("Regulator Driver for TI TPS6586X PMIC");
  MODULE_ALIAS("platform:tps6586x-regulator");