/*
 * tps6507x-regulator.c
 *
 * Regulator driver for TPS65073 PMIC
 *
 * Copyright (C) 2009 Texas Instrument Incorporated - http://www.ti.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 version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
 * whether express or implied; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/tps6507x.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/mfd/tps6507x.h>
#include <linux/regulator/of_regulator.h>

/* DCDC's */
#define TPS6507X_DCDC_1				0
#define TPS6507X_DCDC_2				1
#define TPS6507X_DCDC_3				2
/* LDOs */
#define TPS6507X_LDO_1				3
#define TPS6507X_LDO_2				4

#define TPS6507X_MAX_REG_ID			TPS6507X_LDO_2

/* Number of step-down converters available */
#define TPS6507X_NUM_DCDC			3
/* Number of LDO voltage regulators  available */
#define TPS6507X_NUM_LDO			2
/* Number of total regulators available */
#define TPS6507X_NUM_REGULATOR		(TPS6507X_NUM_DCDC + TPS6507X_NUM_LDO)

/* Supported voltage values for regulators (in microVolts) */
static const unsigned int VDCDCx_VSEL_table[] = {
	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,
	1550000, 1600000, 1650000, 1700000,
	1750000, 1800000, 1850000, 1900000,
	1950000, 2000000, 2050000, 2100000,
	2150000, 2200000, 2250000, 2300000,
	2350000, 2400000, 2450000, 2500000,
	2550000, 2600000, 2650000, 2700000,
	2750000, 2800000, 2850000, 2900000,
	3000000, 3100000, 3200000, 3300000,
};

static const unsigned int LDO1_VSEL_table[] = {
	1000000, 1100000, 1200000, 1250000,
	1300000, 1350000, 1400000, 1500000,
	1600000, 1800000, 2500000, 2750000,
	2800000, 3000000, 3100000, 3300000,
};

/* The voltage mapping table for LDO2 is the same as VDCDCx */
#define LDO2_VSEL_table VDCDCx_VSEL_table

struct tps_info {
	const char *name;
	u8 table_len;
	const unsigned int *table;

	/* Does DCDC high or the low register defines output voltage? */
	bool defdcdc_default;
};

static struct tps_info tps6507x_pmic_regs[] = {
	{
		.name = "VDCDC1",
		.table_len = ARRAY_SIZE(VDCDCx_VSEL_table),
		.table = VDCDCx_VSEL_table,
	},
	{
		.name = "VDCDC2",
		.table_len = ARRAY_SIZE(VDCDCx_VSEL_table),
		.table = VDCDCx_VSEL_table,
	},
	{
		.name = "VDCDC3",
		.table_len = ARRAY_SIZE(VDCDCx_VSEL_table),
		.table = VDCDCx_VSEL_table,
	},
	{
		.name = "LDO1",
		.table_len = ARRAY_SIZE(LDO1_VSEL_table),
		.table = LDO1_VSEL_table,
	},
	{
		.name = "LDO2",
		.table_len = ARRAY_SIZE(LDO2_VSEL_table),
		.table = LDO2_VSEL_table,
	},
};

struct tps6507x_pmic {
	struct regulator_desc desc[TPS6507X_NUM_REGULATOR];
	struct tps6507x_dev *mfd;
	struct regulator_dev *rdev[TPS6507X_NUM_REGULATOR];
	struct tps_info *info[TPS6507X_NUM_REGULATOR];
	struct mutex io_lock;
};
static inline int tps6507x_pmic_read(struct tps6507x_pmic *tps, u8 reg)
{
	u8 val;
	int err;

	err = tps->mfd->read_dev(tps->mfd, reg, 1, &val);

	if (err)
		return err;

	return val;
}

static inline int tps6507x_pmic_write(struct tps6507x_pmic *tps, u8 reg, u8 val)
{
	return tps->mfd->write_dev(tps->mfd, reg, 1, &val);
}

static int tps6507x_pmic_set_bits(struct tps6507x_pmic *tps, u8 reg, u8 mask)
{
	int err, data;

	mutex_lock(&tps->io_lock);

	data = tps6507x_pmic_read(tps, reg);
	if (data < 0) {
		dev_err(tps->mfd->dev, "Read from reg 0x%x failed\n", reg);
		err = data;
		goto out;
	}

	data |= mask;
	err = tps6507x_pmic_write(tps, reg, data);
	if (err)
		dev_err(tps->mfd->dev, "Write for reg 0x%x failed\n", reg);

out:
	mutex_unlock(&tps->io_lock);
	return err;
}

static int tps6507x_pmic_clear_bits(struct tps6507x_pmic *tps, u8 reg, u8 mask)
{
	int err, data;

	mutex_lock(&tps->io_lock);

	data = tps6507x_pmic_read(tps, reg);
	if (data < 0) {
		dev_err(tps->mfd->dev, "Read from reg 0x%x failed\n", reg);
		err = data;
		goto out;
	}

	data &= ~mask;
	err = tps6507x_pmic_write(tps, reg, data);
	if (err)
		dev_err(tps->mfd->dev, "Write for reg 0x%x failed\n", reg);

out:
	mutex_unlock(&tps->io_lock);
	return err;
}

static int tps6507x_pmic_reg_read(struct tps6507x_pmic *tps, u8 reg)
{
	int data;

	mutex_lock(&tps->io_lock);

	data = tps6507x_pmic_read(tps, reg);
	if (data < 0)
		dev_err(tps->mfd->dev, "Read from reg 0x%x failed\n", reg);

	mutex_unlock(&tps->io_lock);
	return data;
}

static int tps6507x_pmic_reg_write(struct tps6507x_pmic *tps, u8 reg, u8 val)
{
	int err;

	mutex_lock(&tps->io_lock);

	err = tps6507x_pmic_write(tps, reg, val);
	if (err < 0)
		dev_err(tps->mfd->dev, "Write for reg 0x%x failed\n", reg);

	mutex_unlock(&tps->io_lock);
	return err;
}

static int tps6507x_pmic_is_enabled(struct regulator_dev *dev)
{
	struct tps6507x_pmic *tps = rdev_get_drvdata(dev);
	int data, rid = rdev_get_id(dev);
	u8 shift;

	if (rid < TPS6507X_DCDC_1 || rid > TPS6507X_LDO_2)
		return -EINVAL;

	shift = TPS6507X_MAX_REG_ID - rid;
	data = tps6507x_pmic_reg_read(tps, TPS6507X_REG_CON_CTRL1);

	if (data < 0)
		return data;
	else
		return (data & 1<<shift) ? 1 : 0;
}

static int tps6507x_pmic_enable(struct regulator_dev *dev)
{
	struct tps6507x_pmic *tps = rdev_get_drvdata(dev);
	int rid = rdev_get_id(dev);
	u8 shift;

	if (rid < TPS6507X_DCDC_1 || rid > TPS6507X_LDO_2)
		return -EINVAL;

	shift = TPS6507X_MAX_REG_ID - rid;
	return tps6507x_pmic_set_bits(tps, TPS6507X_REG_CON_CTRL1, 1 << shift);
}

static int tps6507x_pmic_disable(struct regulator_dev *dev)
{
	struct tps6507x_pmic *tps = rdev_get_drvdata(dev);
	int rid = rdev_get_id(dev);
	u8 shift;

	if (rid < TPS6507X_DCDC_1 || rid > TPS6507X_LDO_2)
		return -EINVAL;

	shift = TPS6507X_MAX_REG_ID - rid;
	return tps6507x_pmic_clear_bits(tps, TPS6507X_REG_CON_CTRL1,
					1 << shift);
}

static int tps6507x_pmic_get_voltage_sel(struct regulator_dev *dev)
{
	struct tps6507x_pmic *tps = rdev_get_drvdata(dev);
	int data, rid = rdev_get_id(dev);
	u8 reg, mask;

	switch (rid) {
	case TPS6507X_DCDC_1:
		reg = TPS6507X_REG_DEFDCDC1;
		mask = TPS6507X_DEFDCDCX_DCDC_MASK;
		break;
	case TPS6507X_DCDC_2:
		if (tps->info[rid]->defdcdc_default)
			reg = TPS6507X_REG_DEFDCDC2_HIGH;
		else
			reg = TPS6507X_REG_DEFDCDC2_LOW;
		mask = TPS6507X_DEFDCDCX_DCDC_MASK;
		break;
	case TPS6507X_DCDC_3:
		if (tps->info[rid]->defdcdc_default)
			reg = TPS6507X_REG_DEFDCDC3_HIGH;
		else
			reg = TPS6507X_REG_DEFDCDC3_LOW;
		mask = TPS6507X_DEFDCDCX_DCDC_MASK;
		break;
	case TPS6507X_LDO_1:
		reg = TPS6507X_REG_LDO_CTRL1;
		mask = TPS6507X_REG_LDO_CTRL1_LDO1_MASK;
		break;
	case TPS6507X_LDO_2:
		reg = TPS6507X_REG_DEFLDO2;
		mask = TPS6507X_REG_DEFLDO2_LDO2_MASK;
		break;
	default:
		return -EINVAL;
	}

	data = tps6507x_pmic_reg_read(tps, reg);
	if (data < 0)
		return data;

	data &= mask;
	return data;
}

static int tps6507x_pmic_set_voltage_sel(struct regulator_dev *dev,
					  unsigned selector)
{
	struct tps6507x_pmic *tps = rdev_get_drvdata(dev);
	int data, rid = rdev_get_id(dev);
	u8 reg, mask;

	switch (rid) {
	case TPS6507X_DCDC_1:
		reg = TPS6507X_REG_DEFDCDC1;
		mask = TPS6507X_DEFDCDCX_DCDC_MASK;
		break;
	case TPS6507X_DCDC_2:
		if (tps->info[rid]->defdcdc_default)
			reg = TPS6507X_REG_DEFDCDC2_HIGH;
		else
			reg = TPS6507X_REG_DEFDCDC2_LOW;
		mask = TPS6507X_DEFDCDCX_DCDC_MASK;
		break;
	case TPS6507X_DCDC_3:
		if (tps->info[rid]->defdcdc_default)
			reg = TPS6507X_REG_DEFDCDC3_HIGH;
		else
			reg = TPS6507X_REG_DEFDCDC3_LOW;
		mask = TPS6507X_DEFDCDCX_DCDC_MASK;
		break;
	case TPS6507X_LDO_1:
		reg = TPS6507X_REG_LDO_CTRL1;
		mask = TPS6507X_REG_LDO_CTRL1_LDO1_MASK;
		break;
	case TPS6507X_LDO_2:
		reg = TPS6507X_REG_DEFLDO2;
		mask = TPS6507X_REG_DEFLDO2_LDO2_MASK;
		break;
	default:
		return -EINVAL;
	}

	data = tps6507x_pmic_reg_read(tps, reg);
	if (data < 0)
		return data;

	data &= ~mask;
	data |= selector;

	return tps6507x_pmic_reg_write(tps, reg, data);
}

static struct regulator_ops tps6507x_pmic_ops = {
	.is_enabled = tps6507x_pmic_is_enabled,
	.enable = tps6507x_pmic_enable,
	.disable = tps6507x_pmic_disable,
	.get_voltage_sel = tps6507x_pmic_get_voltage_sel,
	.set_voltage_sel = tps6507x_pmic_set_voltage_sel,
	.list_voltage = regulator_list_voltage_table,
};

#ifdef CONFIG_OF
static struct of_regulator_match tps6507x_matches[] = {
	{ .name = "VDCDC1"},
	{ .name = "VDCDC2"},
	{ .name = "VDCDC3"},
	{ .name = "LDO1"},
	{ .name = "LDO2"},
};

static struct tps6507x_board *tps6507x_parse_dt_reg_data(
		struct platform_device *pdev,
		struct of_regulator_match **tps6507x_reg_matches)
{
	struct tps6507x_board *tps_board;
	struct device_node *np = pdev->dev.parent->of_node;
	struct device_node *regulators;
	struct of_regulator_match *matches;
	static struct regulator_init_data *reg_data;
	int idx = 0, count, ret;

	tps_board = devm_kzalloc(&pdev->dev, sizeof(*tps_board),
					GFP_KERNEL);
	if (!tps_board) {
		dev_err(&pdev->dev, "Failure to alloc pdata for regulators.\n");
		return NULL;
	}

	regulators = of_find_node_by_name(np, "regulators");
	if (!regulators) {
		dev_err(&pdev->dev, "regulator node not found\n");
		return NULL;
	}

	count = ARRAY_SIZE(tps6507x_matches);
	matches = tps6507x_matches;

	ret = of_regulator_match(&pdev->dev, regulators, matches, count);
	if (ret < 0) {
		dev_err(&pdev->dev, "Error parsing regulator init data: %d\n",
			ret);
		return NULL;
	}

	*tps6507x_reg_matches = matches;

	reg_data = devm_kzalloc(&pdev->dev, (sizeof(struct regulator_init_data)
					* TPS6507X_NUM_REGULATOR), GFP_KERNEL);
	if (!reg_data) {
		dev_err(&pdev->dev, "Failure to alloc init data for regulators.\n");
		return NULL;
	}

	tps_board->tps6507x_pmic_init_data = reg_data;

	for (idx = 0; idx < count; idx++) {
		if (!matches[idx].init_data || !matches[idx].of_node)
			continue;

		memcpy(&reg_data[idx], matches[idx].init_data,
				sizeof(struct regulator_init_data));

	}

	return tps_board;
}
#else
static inline struct tps6507x_board *tps6507x_parse_dt_reg_data(
			struct platform_device *pdev,
			struct of_regulator_match **tps6507x_reg_matches)
{
	*tps6507x_reg_matches = NULL;
	return NULL;
}
#endif
static int tps6507x_pmic_probe(struct platform_device *pdev)
{
	struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent);
	struct tps_info *info = &tps6507x_pmic_regs[0];
	struct regulator_config config = { };
	struct regulator_init_data *init_data;
	struct regulator_dev *rdev;
	struct tps6507x_pmic *tps;
	struct tps6507x_board *tps_board;
	struct of_regulator_match *tps6507x_reg_matches = NULL;
	int i;
	int error;
	unsigned int prop;

	/**
	 * tps_board points to pmic related constants
	 * coming from the board-evm file.
	 */

	tps_board = dev_get_platdata(tps6507x_dev->dev);
	if (!tps_board && tps6507x_dev->dev->of_node)
		tps_board = tps6507x_parse_dt_reg_data(pdev,
						&tps6507x_reg_matches);
	if (!tps_board)
		return -EINVAL;

	/**
	 * init_data points to array of regulator_init structures
	 * coming from the board-evm file.
	 */
	init_data = tps_board->tps6507x_pmic_init_data;
	if (!init_data)
		return -EINVAL;

	tps = devm_kzalloc(&pdev->dev, sizeof(*tps), GFP_KERNEL);
	if (!tps)
		return -ENOMEM;

	mutex_init(&tps->io_lock);

	/* common for all regulators */
	tps->mfd = tps6507x_dev;

	for (i = 0; i < TPS6507X_NUM_REGULATOR; i++, info++, init_data++) {
		/* Register the regulators */
		tps->info[i] = info;
		if (init_data->driver_data) {
			struct tps6507x_reg_platform_data *data =
							init_data->driver_data;
			tps->info[i]->defdcdc_default = data->defdcdc_default;
		}

		tps->desc[i].name = info->name;
		tps->desc[i].id = i;
		tps->desc[i].n_voltages = info->table_len;
		tps->desc[i].volt_table = info->table;
		tps->desc[i].ops = &tps6507x_pmic_ops;
		tps->desc[i].type = REGULATOR_VOLTAGE;
		tps->desc[i].owner = THIS_MODULE;

		config.dev = tps6507x_dev->dev;
		config.init_data = init_data;
		config.driver_data = tps;

		if (tps6507x_reg_matches) {
			error = of_property_read_u32(
				tps6507x_reg_matches[i].of_node,
					"ti,defdcdc_default", &prop);

			if (!error)
				tps->info[i]->defdcdc_default = prop;

			config.of_node = tps6507x_reg_matches[i].of_node;
		}

		rdev = regulator_register(&tps->desc[i], &config);
		if (IS_ERR(rdev)) {
			dev_err(tps6507x_dev->dev,
				"failed to register %s regulator\n",
				pdev->name);
			error = PTR_ERR(rdev);
			goto fail;
		}

		/* Save regulator for cleanup */
		tps->rdev[i] = rdev;
	}

	tps6507x_dev->pmic = tps;
	platform_set_drvdata(pdev, tps6507x_dev);

	return 0;

fail:
	while (--i >= 0)
		regulator_unregister(tps->rdev[i]);
	return error;
}

static int tps6507x_pmic_remove(struct platform_device *pdev)
{
	struct tps6507x_dev *tps6507x_dev = platform_get_drvdata(pdev);
	struct tps6507x_pmic *tps = tps6507x_dev->pmic;
	int i;

	for (i = 0; i < TPS6507X_NUM_REGULATOR; i++)
		regulator_unregister(tps->rdev[i]);
	return 0;
}

static struct platform_driver tps6507x_pmic_driver = {
	.driver = {
		.name = "tps6507x-pmic",
		.owner = THIS_MODULE,
	},
	.probe = tps6507x_pmic_probe,
	.remove = tps6507x_pmic_remove,
};

static int __init tps6507x_pmic_init(void)
{
	return platform_driver_register(&tps6507x_pmic_driver);
}
subsys_initcall(tps6507x_pmic_init);

static void __exit tps6507x_pmic_cleanup(void)
{
	platform_driver_unregister(&tps6507x_pmic_driver);
}
module_exit(tps6507x_pmic_cleanup);

MODULE_AUTHOR("Texas Instruments");
MODULE_DESCRIPTION("TPS6507x voltage regulator driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:tps6507x-pmic");