xref: /linux/drivers/regulator/isl6271a-regulator.c (revision 5148fa52a12fa1b97c730b2fe321f2aad7ea041c)
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 */
32 struct isl_pmic {
33 	struct i2c_client	*client;
34 	struct regulator_dev	*rdev[3];
35 	struct mutex		mtx;
36 };
37 
38 static 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 
53 static 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 
69 static 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 
76 static int isl6271a_get_fixed_voltage(struct regulator_dev *dev)
77 {
78 	int id = rdev_get_id(dev);
79 	return (id == 1) ? 1100000 : 1300000;
80 }
81 
82 static int isl6271a_list_fixed_voltage(struct regulator_dev *dev, unsigned selector)
83 {
84 	int id = rdev_get_id(dev);
85 	return (id == 1) ? 1100000 : 1300000;
86 }
87 
88 static struct regulator_ops isl_fixed_ops = {
89 	.get_voltage	= isl6271a_get_fixed_voltage,
90 	.list_voltage	= isl6271a_list_fixed_voltage,
91 };
92 
93 static const struct regulator_desc isl_rd[] = {
94 	{
95 		.name		= "Core Buck",
96 		.id		= 0,
97 		.n_voltages	= 16,
98 		.ops		= &isl_core_ops,
99 		.type		= REGULATOR_VOLTAGE,
100 		.owner		= THIS_MODULE,
101 		.min_uV		= ISL6271A_VOLTAGE_MIN,
102 		.uV_step	= ISL6271A_VOLTAGE_STEP,
103 	}, {
104 		.name		= "LDO1",
105 		.id		= 1,
106 		.n_voltages	= 1,
107 		.ops		= &isl_fixed_ops,
108 		.type		= REGULATOR_VOLTAGE,
109 		.owner		= THIS_MODULE,
110 	}, {
111 		.name		= "LDO2",
112 		.id		= 2,
113 		.n_voltages	= 1,
114 		.ops		= &isl_fixed_ops,
115 		.type		= REGULATOR_VOLTAGE,
116 		.owner		= THIS_MODULE,
117 	},
118 };
119 
120 static int __devinit isl6271a_probe(struct i2c_client *i2c,
121 				     const struct i2c_device_id *id)
122 {
123 	struct regulator_config config = { };
124 	struct regulator_init_data *init_data	= i2c->dev.platform_data;
125 	struct isl_pmic *pmic;
126 	int err, i;
127 
128 	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
129 		return -EIO;
130 
131 	pmic = devm_kzalloc(&i2c->dev, sizeof(struct isl_pmic), GFP_KERNEL);
132 	if (!pmic)
133 		return -ENOMEM;
134 
135 	pmic->client = i2c;
136 
137 	mutex_init(&pmic->mtx);
138 
139 	for (i = 0; i < 3; i++) {
140 		config.dev = &i2c->dev;
141 		if (i == 0)
142 			config.init_data = init_data;
143 		else
144 			config.init_data = 0;
145 		config.driver_data = pmic;
146 
147 		pmic->rdev[i] = regulator_register(&isl_rd[i], &config);
148 		if (IS_ERR(pmic->rdev[i])) {
149 			dev_err(&i2c->dev, "failed to register %s\n", id->name);
150 			err = PTR_ERR(pmic->rdev[i]);
151 			goto error;
152 		}
153 	}
154 
155 	i2c_set_clientdata(i2c, pmic);
156 
157 	return 0;
158 
159 error:
160 	while (--i >= 0)
161 		regulator_unregister(pmic->rdev[i]);
162 	return err;
163 }
164 
165 static int __devexit isl6271a_remove(struct i2c_client *i2c)
166 {
167 	struct isl_pmic *pmic = i2c_get_clientdata(i2c);
168 	int i;
169 
170 	for (i = 0; i < 3; i++)
171 		regulator_unregister(pmic->rdev[i]);
172 	return 0;
173 }
174 
175 static const struct i2c_device_id isl6271a_id[] = {
176 	{.name = "isl6271a", 0 },
177 	{ },
178 };
179 
180 MODULE_DEVICE_TABLE(i2c, isl6271a_id);
181 
182 static struct i2c_driver isl6271a_i2c_driver = {
183 	.driver = {
184 		.name = "isl6271a",
185 		.owner = THIS_MODULE,
186 	},
187 	.probe = isl6271a_probe,
188 	.remove = __devexit_p(isl6271a_remove),
189 	.id_table = isl6271a_id,
190 };
191 
192 static int __init isl6271a_init(void)
193 {
194 	return i2c_add_driver(&isl6271a_i2c_driver);
195 }
196 
197 static void __exit isl6271a_cleanup(void)
198 {
199 	i2c_del_driver(&isl6271a_i2c_driver);
200 }
201 
202 subsys_initcall(isl6271a_init);
203 module_exit(isl6271a_cleanup);
204 
205 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
206 MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
207 MODULE_LICENSE("GPL v2");
208