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[] __maybe_unused = {
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		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
148		.of_match_table = of_match_ptr(mp8859_dt_id),
149	},
150	.probe = mp8859_i2c_probe,
151	.id_table = mp8859_i2c_id,
152};
153
154module_i2c_driver(mp8859_regulator_driver);
155
156MODULE_DESCRIPTION("Monolithic Power Systems MP8859 voltage regulator driver");
157MODULE_AUTHOR("Markus Reichl <m.reichl@fivetechno.de>");
158MODULE_LICENSE("GPL v2");
159