// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2023 Analog Devices, Inc.
 * ADI regulator driver for MAX77503.
 */

#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/util_macros.h>

#define MAX77503_REG_CFG			0x00
#define MAX77503_REG_VOUT			0x01

#define MAX77503_BIT_EN				BIT(0)
#define MAX77503_BIT_CURR_LIM		BIT(3)
#define MAX77503_BIT_ADEN			BIT(6)

#define MAX77503_BITS_SOFT_START	GENMASK(5, 4)
#define MAX77503_BITS_MX_VOUT		GENMASK(7, 0)

#define MAX77503_AD_ENABLED			0x1
#define MAX77503_AD_DISABLED		0x0

struct max77503_dev {
	struct device *dev;
	struct device_node *of_node;
	struct regulator_desc desc;
	struct regulator_dev *rdev;
	struct regmap *regmap;
};

static const struct regmap_config max77503_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = 0x2,
};

static const struct regulator_ops max77503_buck_ops = {
	.list_voltage = regulator_list_voltage_linear_range,
	.map_voltage = regulator_map_voltage_ascend,
	.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,
	.get_current_limit = regulator_get_current_limit_regmap,
	.set_current_limit = regulator_set_current_limit_regmap,
	.set_active_discharge = regulator_set_active_discharge_regmap,
	.set_soft_start = regulator_set_soft_start_regmap,
};

static const struct linear_range max77503_buck_ranges[] = {
	REGULATOR_LINEAR_RANGE(800000, 0x00, 0x54, 50000)
};

static const unsigned int max77503_current_limit_table[] = {
	500000, 2000000
};

static const struct regulator_desc max77503_regulators_desc = {
	.name = "max77503",
	.enable_reg = MAX77503_REG_CFG,
	.enable_mask = MAX77503_BIT_EN,
	.ops = &max77503_buck_ops,
	.type = REGULATOR_VOLTAGE,
	.linear_ranges = max77503_buck_ranges,
	.n_linear_ranges = ARRAY_SIZE(max77503_buck_ranges),
	.vsel_reg = MAX77503_REG_VOUT,
	.vsel_mask = MAX77503_BITS_MX_VOUT,
	.soft_start_reg = MAX77503_REG_CFG,
	.soft_start_mask = MAX77503_BITS_SOFT_START,
	.active_discharge_reg = MAX77503_REG_CFG,
	.active_discharge_mask = MAX77503_BIT_ADEN,
	.active_discharge_off = MAX77503_AD_DISABLED,
	.active_discharge_on = MAX77503_AD_ENABLED,
	.csel_reg = MAX77503_REG_CFG,
	.csel_mask = MAX77503_BIT_CURR_LIM,
	.curr_table = max77503_current_limit_table,
	.n_current_limits = ARRAY_SIZE(max77503_current_limit_table),
	.owner = THIS_MODULE,
};

static int max77503_regulator_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct regulator_config config = {};
	struct regulator_dev *rdev;

	config.dev = dev;
	config.of_node = dev->of_node;
	config.regmap = devm_regmap_init_i2c(client, &max77503_regmap_config);
	if (IS_ERR(config.regmap)) {
		dev_err(dev, "Failed to init regmap");
		return PTR_ERR(config.regmap);
	}

	rdev = devm_regulator_register(dev, &max77503_regulators_desc, &config);
	if (IS_ERR(rdev)) {
		dev_err(dev, "Failed to register regulator MAX77503");
		return PTR_ERR(rdev);
	}

	return 0;
}

static const struct of_device_id of_max77503_match_tbl[] = {
	{ .compatible = "adi,max77503", },
	{ }
};

MODULE_DEVICE_TABLE(of, of_max77503_match_tbl);

static const struct i2c_device_id max77503_regulator_id[] = {
	{"max77503"},
	{ }
};

MODULE_DEVICE_TABLE(i2c, max77503_regulator_id);

static struct i2c_driver max77503_regulator_driver = {
	.driver = {
		.name = "max77503",
		.of_match_table = of_max77503_match_tbl
	},
	.probe = max77503_regulator_probe,
	.id_table = max77503_regulator_id,
};

module_i2c_driver(max77503_regulator_driver);

MODULE_AUTHOR("Gokhan Celik <Gokhan.Celik@analog.com>");
MODULE_DESCRIPTION("MAX77503 regulator driver");
MODULE_LICENSE("GPL");