1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Copyright (c) 2019 five technologies GmbH
  4// Author: Markus Reichl <m.reichl@fivetechno.de>
  5
  6#include <linux/module.h>
  7#include <linux/i2c.h>
  8#include <linux/of.h>
  9#include <linux/regulator/driver.h>
 10#include <linux/regmap.h>
 11
 12
 13#define VOL_MIN_IDX			0x00
 14#define VOL_MAX_IDX			0x7ff
 15
 16/* Register definitions */
 17#define MP8859_VOUT_L_REG		0    //3 lo Bits
 18#define MP8859_VOUT_H_REG		1    //8 hi Bits
 19#define MP8859_VOUT_GO_REG		2
 20#define MP8859_IOUT_LIM_REG		3
 21#define MP8859_CTL1_REG			4
 22#define MP8859_CTL2_REG			5
 23#define MP8859_RESERVED1_REG		6
 24#define MP8859_RESERVED2_REG		7
 25#define MP8859_RESERVED3_REG		8
 26#define MP8859_STATUS_REG		9
 27#define MP8859_INTERRUPT_REG		0x0A
 28#define MP8859_MASK_REG			0x0B
 29#define MP8859_ID1_REG			0x0C
 30#define MP8859_MFR_ID_REG		0x27
 31#define MP8859_DEV_ID_REG		0x28
 32#define MP8859_IC_REV_REG		0x29
 33
 34#define MP8859_MAX_REG			0x29
 35
 36#define MP8859_GO_BIT			0x01
 37
 38
 39static int mp8859_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
 40{
 41	int ret;
 42
 43	ret = regmap_write(rdev->regmap, MP8859_VOUT_L_REG, sel & 0x7);
 44
 45	if (ret)
 46		return ret;
 47	ret = regmap_write(rdev->regmap, MP8859_VOUT_H_REG, sel >> 3);
 48
 49	if (ret)
 50		return ret;
 51	ret = regmap_update_bits(rdev->regmap, MP8859_VOUT_GO_REG,
 52					MP8859_GO_BIT, 1);
 53	return ret;
 54}
 55
 56static int mp8859_get_voltage_sel(struct regulator_dev *rdev)
 57{
 58	unsigned int val_tmp;
 59	unsigned int val;
 60	int ret;
 61
 62	ret = regmap_read(rdev->regmap, MP8859_VOUT_H_REG, &val_tmp);
 63
 64	if (ret)
 65		return ret;
 66	val = val_tmp << 3;
 67
 68	ret = regmap_read(rdev->regmap, MP8859_VOUT_L_REG, &val_tmp);
 69
 70	if (ret)
 71		return ret;
 72	val |= val_tmp & 0x07;
 73	return val;
 74}
 75
 76static const struct linear_range mp8859_dcdc_ranges[] = {
 77	REGULATOR_LINEAR_RANGE(0, VOL_MIN_IDX, VOL_MAX_IDX, 10000),
 78};
 79
 80static const struct regmap_config mp8859_regmap = {
 81	.reg_bits = 8,
 82	.val_bits = 8,
 83	.max_register = MP8859_MAX_REG,
 84	.cache_type = REGCACHE_RBTREE,
 85};
 86
 87static const struct regulator_ops mp8859_ops = {
 88	.set_voltage_sel = mp8859_set_voltage_sel,
 89	.get_voltage_sel = mp8859_get_voltage_sel,
 90	.list_voltage = regulator_list_voltage_linear_range,
 91};
 92
 93static const struct regulator_desc mp8859_regulators[] = {
 94	{
 95		.id = 0,
 96		.type = REGULATOR_VOLTAGE,
 97		.name = "mp8859_dcdc",
 98		.supply_name = "vin",
 99		.of_match = of_match_ptr("mp8859_dcdc"),
100		.n_voltages = VOL_MAX_IDX + 1,
101		.linear_ranges = mp8859_dcdc_ranges,
102		.n_linear_ranges = 1,
103		.ops = &mp8859_ops,
104		.owner = THIS_MODULE,
105	},
106};
107
108static int mp8859_i2c_probe(struct i2c_client *i2c)
109{
110	int ret;
111	struct regulator_config config = {.dev = &i2c->dev};
112	struct regmap *regmap = devm_regmap_init_i2c(i2c, &mp8859_regmap);
113	struct regulator_dev *rdev;
114
115	if (IS_ERR(regmap)) {
116		ret = PTR_ERR(regmap);
117		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
118		return ret;
119	}
120	rdev = devm_regulator_register(&i2c->dev, &mp8859_regulators[0],
121					&config);
122
123	if (IS_ERR(rdev)) {
124		ret = PTR_ERR(rdev);
125		dev_err(&i2c->dev, "failed to register %s: %d\n",
126			mp8859_regulators[0].name, ret);
127		return ret;
128	}
129	return 0;
130}
131
132static const struct of_device_id mp8859_dt_id[] = {
133	{.compatible =  "mps,mp8859"},
134	{},
135};
136MODULE_DEVICE_TABLE(of, mp8859_dt_id);
137
138static const struct i2c_device_id mp8859_i2c_id[] = {
139	{ "mp8859", },
140	{  },
141};
142MODULE_DEVICE_TABLE(i2c, mp8859_i2c_id);
143
144static struct i2c_driver mp8859_regulator_driver = {
145	.driver = {
146		.name = "mp8859",
147		.of_match_table = of_match_ptr(mp8859_dt_id),
148	},
149	.probe_new = mp8859_i2c_probe,
150	.id_table = mp8859_i2c_id,
151};
152
153module_i2c_driver(mp8859_regulator_driver);
154
155MODULE_DESCRIPTION("Monolithic Power Systems MP8859 voltage regulator driver");
156MODULE_AUTHOR("Markus Reichl <m.reichl@fivetechno.de>");
157MODULE_LICENSE("GPL v2");