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 regulator_dev	*rdev[3];
35	struct mutex		mtx;
36};
37
38static int isl6271a_get_voltage_sel(struct regulator_dev *dev)
39{
40	struct isl_pmic *pmic = rdev_get_drvdata(dev);
41	int idx;
42
43	mutex_lock(&pmic->mtx);
44
45	idx = i2c_smbus_read_byte(pmic->client);
46	if (idx < 0)
47		dev_err(&pmic->client->dev, "Error getting voltage\n");
48
49	mutex_unlock(&pmic->mtx);
50	return idx;
51}
52
53static int isl6271a_set_voltage_sel(struct regulator_dev *dev,
54				    unsigned selector)
55{
56	struct isl_pmic *pmic = rdev_get_drvdata(dev);
57	int err;
58
59	mutex_lock(&pmic->mtx);
60
61	err = i2c_smbus_write_byte(pmic->client, selector);
62	if (err < 0)
63		dev_err(&pmic->client->dev, "Error setting voltage\n");
64
65	mutex_unlock(&pmic->mtx);
66	return err;
67}
68
69static struct regulator_ops isl_core_ops = {
70	.get_voltage_sel = isl6271a_get_voltage_sel,
71	.set_voltage_sel = isl6271a_set_voltage_sel,
72	.list_voltage	= regulator_list_voltage_linear,
73	.map_voltage	= regulator_map_voltage_linear,
74};
75
76static struct regulator_ops isl_fixed_ops = {
77	.list_voltage	= regulator_list_voltage_linear,
78};
79
80static const struct regulator_desc isl_rd[] = {
81	{
82		.name		= "Core Buck",
83		.id		= 0,
84		.n_voltages	= 16,
85		.ops		= &isl_core_ops,
86		.type		= REGULATOR_VOLTAGE,
87		.owner		= THIS_MODULE,
88		.min_uV		= ISL6271A_VOLTAGE_MIN,
89		.uV_step	= ISL6271A_VOLTAGE_STEP,
90	}, {
91		.name		= "LDO1",
92		.id		= 1,
93		.n_voltages	= 1,
94		.ops		= &isl_fixed_ops,
95		.type		= REGULATOR_VOLTAGE,
96		.owner		= THIS_MODULE,
97		.min_uV		= 1100000,
98	}, {
99		.name		= "LDO2",
100		.id		= 2,
101		.n_voltages	= 1,
102		.ops		= &isl_fixed_ops,
103		.type		= REGULATOR_VOLTAGE,
104		.owner		= THIS_MODULE,
105		.min_uV		= 1300000,
106	},
107};
108
109static int isl6271a_probe(struct i2c_client *i2c,
110				     const struct i2c_device_id *id)
111{
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		pmic->rdev[i] = devm_regulator_register(&i2c->dev, &isl_rd[i],
137							&config);
138		if (IS_ERR(pmic->rdev[i])) {
139			dev_err(&i2c->dev, "failed to register %s\n", id->name);
140			return PTR_ERR(pmic->rdev[i]);
141		}
142	}
143
144	i2c_set_clientdata(i2c, pmic);
145
146	return 0;
147}
148
149static const struct i2c_device_id isl6271a_id[] = {
150	{.name = "isl6271a", 0 },
151	{ },
152};
153
154MODULE_DEVICE_TABLE(i2c, isl6271a_id);
155
156static struct i2c_driver isl6271a_i2c_driver = {
157	.driver = {
158		.name = "isl6271a",
159		.owner = THIS_MODULE,
160	},
161	.probe = isl6271a_probe,
162	.id_table = isl6271a_id,
163};
164
165static int __init isl6271a_init(void)
166{
167	return i2c_add_driver(&isl6271a_i2c_driver);
168}
169
170static void __exit isl6271a_cleanup(void)
171{
172	i2c_del_driver(&isl6271a_i2c_driver);
173}
174
175subsys_initcall(isl6271a_init);
176module_exit(isl6271a_cleanup);
177
178MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
179MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
180MODULE_LICENSE("GPL v2");
181