1/*
2 * isl6271a-regulator.c
3 *
4 * Support for Intersil ISL6271A voltage regulator
5 *
6 * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation version 2.
11 *
12 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
13 * whether express or implied; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 */
17
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/err.h>
22#include <linux/platform_device.h>
23#include <linux/regulator/driver.h>
24#include <linux/i2c.h>
25#include <linux/slab.h>
26
27#define	ISL6271A_VOLTAGE_MIN	850000
28#define	ISL6271A_VOLTAGE_MAX	1600000
29#define	ISL6271A_VOLTAGE_STEP	50000
30
31/* PMIC details */
32struct isl_pmic {
33	struct i2c_client	*client;
34	struct mutex		mtx;
35};
36
37static int isl6271a_get_voltage_sel(struct regulator_dev *dev)
38{
39	struct isl_pmic *pmic = rdev_get_drvdata(dev);
40	int idx;
41
42	mutex_lock(&pmic->mtx);
43
44	idx = i2c_smbus_read_byte(pmic->client);
45	if (idx < 0)
46		dev_err(&pmic->client->dev, "Error getting voltage\n");
47
48	mutex_unlock(&pmic->mtx);
49	return idx;
50}
51
52static int isl6271a_set_voltage_sel(struct regulator_dev *dev,
53				    unsigned selector)
54{
55	struct isl_pmic *pmic = rdev_get_drvdata(dev);
56	int err;
57
58	mutex_lock(&pmic->mtx);
59
60	err = i2c_smbus_write_byte(pmic->client, selector);
61	if (err < 0)
62		dev_err(&pmic->client->dev, "Error setting voltage\n");
63
64	mutex_unlock(&pmic->mtx);
65	return err;
66}
67
68static const struct regulator_ops isl_core_ops = {
69	.get_voltage_sel = isl6271a_get_voltage_sel,
70	.set_voltage_sel = isl6271a_set_voltage_sel,
71	.list_voltage	= regulator_list_voltage_linear,
72	.map_voltage	= regulator_map_voltage_linear,
73};
74
75static const struct regulator_ops isl_fixed_ops = {
76	.list_voltage	= regulator_list_voltage_linear,
77};
78
79static const struct regulator_desc isl_rd[] = {
80	{
81		.name		= "Core Buck",
82		.id		= 0,
83		.n_voltages	= 16,
84		.ops		= &isl_core_ops,
85		.type		= REGULATOR_VOLTAGE,
86		.owner		= THIS_MODULE,
87		.min_uV		= ISL6271A_VOLTAGE_MIN,
88		.uV_step	= ISL6271A_VOLTAGE_STEP,
89	}, {
90		.name		= "LDO1",
91		.id		= 1,
92		.n_voltages	= 1,
93		.ops		= &isl_fixed_ops,
94		.type		= REGULATOR_VOLTAGE,
95		.owner		= THIS_MODULE,
96		.min_uV		= 1100000,
97	}, {
98		.name		= "LDO2",
99		.id		= 2,
100		.n_voltages	= 1,
101		.ops		= &isl_fixed_ops,
102		.type		= REGULATOR_VOLTAGE,
103		.owner		= THIS_MODULE,
104		.min_uV		= 1300000,
105	},
106};
107
108static int isl6271a_probe(struct i2c_client *i2c,
109				     const struct i2c_device_id *id)
110{
111	struct regulator_dev *rdev;
112	struct regulator_config config = { };
113	struct regulator_init_data *init_data	= dev_get_platdata(&i2c->dev);
114	struct isl_pmic *pmic;
115	int i;
116
117	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
118		return -EIO;
119
120	pmic = devm_kzalloc(&i2c->dev, sizeof(struct isl_pmic), GFP_KERNEL);
121	if (!pmic)
122		return -ENOMEM;
123
124	pmic->client = i2c;
125
126	mutex_init(&pmic->mtx);
127
128	for (i = 0; i < 3; i++) {
129		config.dev = &i2c->dev;
130		if (i == 0)
131			config.init_data = init_data;
132		else
133			config.init_data = NULL;
134		config.driver_data = pmic;
135
136		rdev = devm_regulator_register(&i2c->dev, &isl_rd[i], &config);
137		if (IS_ERR(rdev)) {
138			dev_err(&i2c->dev, "failed to register %s\n", id->name);
139			return PTR_ERR(rdev);
140		}
141	}
142
143	i2c_set_clientdata(i2c, pmic);
144
145	return 0;
146}
147
148static const struct i2c_device_id isl6271a_id[] = {
149	{.name = "isl6271a", 0 },
150	{ },
151};
152
153MODULE_DEVICE_TABLE(i2c, isl6271a_id);
154
155static struct i2c_driver isl6271a_i2c_driver = {
156	.driver = {
157		.name = "isl6271a",
158	},
159	.probe = isl6271a_probe,
160	.id_table = isl6271a_id,
161};
162
163static int __init isl6271a_init(void)
164{
165	return i2c_add_driver(&isl6271a_i2c_driver);
166}
167
168static void __exit isl6271a_cleanup(void)
169{
170	i2c_del_driver(&isl6271a_i2c_driver);
171}
172
173subsys_initcall(isl6271a_init);
174module_exit(isl6271a_cleanup);
175
176MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
177MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
178MODULE_LICENSE("GPL v2");
179