regulator: mp8859: add driver

// SPDX-License-Identifier: GPL-2.0

//

// Copyright (c) 2019 five technologies GmbH

// Author: Markus Reichl <m.reichl@fivetechno.de>

#include <linux/module.h>

#include <linux/i2c.h>

#include <linux/of.h>

#include <linux/regulator/driver.h>

#include <linux/regmap.h>

#define VOL_MIN_IDX			0x00

#define VOL_MAX_IDX			0x7ff

/* Register definitions */

#define MP8859_VOUT_L_REG		0    //3 lo Bits

#define MP8859_VOUT_H_REG		1    //8 hi Bits

#define MP8859_VOUT_GO_REG		2

#define MP8859_IOUT_LIM_REG		3

#define MP8859_CTL1_REG			4

#define MP8859_CTL2_REG			5

#define MP8859_RESERVED1_REG		6

#define MP8859_RESERVED2_REG		7

#define MP8859_RESERVED3_REG		8

#define MP8859_STATUS_REG		9

#define MP8859_INTERRUPT_REG		0x0A

#define MP8859_MASK_REG			0x0B

#define MP8859_ID1_REG			0x0C

#define MP8859_MFR_ID_REG		0x27

#define MP8859_DEV_ID_REG		0x28

#define MP8859_IC_REV_REG		0x29

#define MP8859_MAX_REG			0x29

#define MP8859_GO_BIT			0x01

static int mp8859_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)

{

	int ret;

	ret = regmap_write(rdev->regmap, MP8859_VOUT_L_REG, sel & 0x7);

	if (ret)

		return ret;

	ret = regmap_write(rdev->regmap, MP8859_VOUT_H_REG, sel >> 3);

	if (ret)

		return ret;

	ret = regmap_update_bits(rdev->regmap, MP8859_VOUT_GO_REG,

					MP8859_GO_BIT, 1);

	return ret;

}

static int mp8859_get_voltage_sel(struct regulator_dev *rdev)

{

	unsigned int val_tmp;

	unsigned int val;

	int ret;

	ret = regmap_read(rdev->regmap, MP8859_VOUT_H_REG, &val_tmp);

	if (ret)

		return ret;

	val = val_tmp << 3;

	ret = regmap_read(rdev->regmap, MP8859_VOUT_L_REG, &val_tmp);

	if (ret)

		return ret;

	val |= val_tmp & 0x07;

	return val;

}

static const struct regulator_linear_range mp8859_dcdc_ranges[] = {

	REGULATOR_LINEAR_RANGE(0, VOL_MIN_IDX, VOL_MAX_IDX, 10000),

};

static const struct regmap_config mp8859_regmap = {

	.reg_bits = 8,

	.val_bits = 8,

	.max_register = MP8859_MAX_REG,

	.cache_type = REGCACHE_RBTREE,

};

static const struct regulator_ops mp8859_ops = {

	.set_voltage_sel = mp8859_set_voltage_sel,

	.get_voltage_sel = mp8859_get_voltage_sel,

	.list_voltage = regulator_list_voltage_linear_range,

};

static const struct regulator_desc mp8859_regulators[] = {

	{

		.id = 0,

		.type = REGULATOR_VOLTAGE,

		.name = "mp8859_dcdc",

		.of_match = of_match_ptr("mp8859_dcdc"),

		.n_voltages = VOL_MAX_IDX + 1,

		.linear_ranges = mp8859_dcdc_ranges,

		.n_linear_ranges = 1,

		.ops = &mp8859_ops,

		.owner = THIS_MODULE,

	},

};

static int mp8859_i2c_probe(struct i2c_client *i2c)

{

	int ret;

	struct regulator_config config = {.dev = &i2c->dev};

	struct regmap *regmap = devm_regmap_init_i2c(i2c, &mp8859_regmap);

	struct regulator_dev *rdev;

	if (IS_ERR(regmap)) {

		ret = PTR_ERR(regmap);

		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);

		return ret;

	}

	rdev = devm_regulator_register(&i2c->dev, &mp8859_regulators[0],

					&config);

	if (IS_ERR(rdev)) {

		ret = PTR_ERR(rdev);

		dev_err(&i2c->dev, "failed to register %s: %d\n",

			mp8859_regulators[0].name, ret);

			return ret;

		}

	return 0;

}

static const struct of_device_id mp8859_dt_id[] = {

	{.compatible =  "mps,mp8859"},

	{},

};

MODULE_DEVICE_TABLE(of, mp8859_dt_id);

static const struct i2c_device_id mp8859_i2c_id[] = {

	{ "mp8859", },

	{  },

};

MODULE_DEVICE_TABLE(i2c, mp8859_i2c_id);

static struct i2c_driver mp8859_regulator_driver = {

	.driver = {

		.name = "mp8859",

		.of_match_table = of_match_ptr(mp8859_dt_id),

	},

	.probe_new = mp8859_i2c_probe,

	.id_table = mp8859_i2c_id,

};

module_i2c_driver(mp8859_regulator_driver);

MODULE_DESCRIPTION("Monolithic Power Systems MP8859 voltage regulator driver");

MODULE_AUTHOR("Markus Reichl <m.reichl@fivetechno.de>");

MODULE_LICENSE("GPL v2");