Merge branch 'akpm'
[linux-2.6/next.git] / drivers / regulator / isl6271a-regulator.c
blobe4b3592e81767856cdadd4543a6e25bb001d695d
1 /*
2 * isl6271a-regulator.c
4 * Support for Intersil ISL6271A voltage regulator
6 * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
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.
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.
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/delay.h>
26 #include <linux/slab.h>
28 #define ISL6271A_VOLTAGE_MIN 850000
29 #define ISL6271A_VOLTAGE_MAX 1600000
30 #define ISL6271A_VOLTAGE_STEP 50000
32 /* PMIC details */
33 struct isl_pmic {
34 struct i2c_client *client;
35 struct regulator_dev *rdev[3];
36 struct mutex mtx;
39 static int isl6271a_get_voltage(struct regulator_dev *dev)
41 struct isl_pmic *pmic = rdev_get_drvdata(dev);
42 int idx, data;
44 mutex_lock(&pmic->mtx);
46 idx = i2c_smbus_read_byte(pmic->client);
47 if (idx < 0) {
48 dev_err(&pmic->client->dev, "Error getting voltage\n");
49 data = idx;
50 goto out;
53 /* Convert the data from chip to microvolts */
54 data = ISL6271A_VOLTAGE_MIN + (ISL6271A_VOLTAGE_STEP * (idx & 0xf));
56 out:
57 mutex_unlock(&pmic->mtx);
58 return data;
61 static int isl6271a_set_voltage(struct regulator_dev *dev,
62 int minuV, int maxuV,
63 unsigned *selector)
65 struct isl_pmic *pmic = rdev_get_drvdata(dev);
66 int vsel, err, data;
68 if (minuV < ISL6271A_VOLTAGE_MIN || minuV > ISL6271A_VOLTAGE_MAX)
69 return -EINVAL;
70 if (maxuV < ISL6271A_VOLTAGE_MIN || maxuV > ISL6271A_VOLTAGE_MAX)
71 return -EINVAL;
73 /* Align to 50000 mV */
74 vsel = minuV - (minuV % ISL6271A_VOLTAGE_STEP);
76 /* If the result fell out of [minuV,maxuV] range, put it back */
77 if (vsel < minuV)
78 vsel += ISL6271A_VOLTAGE_STEP;
80 /* Convert the microvolts to data for the chip */
81 data = (vsel - ISL6271A_VOLTAGE_MIN) / ISL6271A_VOLTAGE_STEP;
83 *selector = data;
85 mutex_lock(&pmic->mtx);
87 err = i2c_smbus_write_byte(pmic->client, data);
88 if (err < 0)
89 dev_err(&pmic->client->dev, "Error setting voltage\n");
91 mutex_unlock(&pmic->mtx);
92 return err;
95 static int isl6271a_list_voltage(struct regulator_dev *dev, unsigned selector)
97 return ISL6271A_VOLTAGE_MIN + (ISL6271A_VOLTAGE_STEP * selector);
100 static struct regulator_ops isl_core_ops = {
101 .get_voltage = isl6271a_get_voltage,
102 .set_voltage = isl6271a_set_voltage,
103 .list_voltage = isl6271a_list_voltage,
106 static int isl6271a_get_fixed_voltage(struct regulator_dev *dev)
108 int id = rdev_get_id(dev);
109 return (id == 1) ? 1100000 : 1300000;
112 static int isl6271a_list_fixed_voltage(struct regulator_dev *dev, unsigned selector)
114 int id = rdev_get_id(dev);
115 return (id == 1) ? 1100000 : 1300000;
118 static struct regulator_ops isl_fixed_ops = {
119 .get_voltage = isl6271a_get_fixed_voltage,
120 .list_voltage = isl6271a_list_fixed_voltage,
123 static struct regulator_desc isl_rd[] = {
125 .name = "Core Buck",
126 .id = 0,
127 .n_voltages = 16,
128 .ops = &isl_core_ops,
129 .type = REGULATOR_VOLTAGE,
130 .owner = THIS_MODULE,
131 }, {
132 .name = "LDO1",
133 .id = 1,
134 .n_voltages = 1,
135 .ops = &isl_fixed_ops,
136 .type = REGULATOR_VOLTAGE,
137 .owner = THIS_MODULE,
138 }, {
139 .name = "LDO2",
140 .id = 2,
141 .n_voltages = 1,
142 .ops = &isl_fixed_ops,
143 .type = REGULATOR_VOLTAGE,
144 .owner = THIS_MODULE,
148 static int __devinit isl6271a_probe(struct i2c_client *i2c,
149 const struct i2c_device_id *id)
151 struct regulator_init_data *init_data = i2c->dev.platform_data;
152 struct isl_pmic *pmic;
153 int err, i;
155 if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
156 return -EIO;
158 if (!init_data) {
159 dev_err(&i2c->dev, "no platform data supplied\n");
160 return -EIO;
163 pmic = kzalloc(sizeof(struct isl_pmic), GFP_KERNEL);
164 if (!pmic)
165 return -ENOMEM;
167 pmic->client = i2c;
169 mutex_init(&pmic->mtx);
171 for (i = 0; i < 3; i++) {
172 pmic->rdev[i] = regulator_register(&isl_rd[i], &i2c->dev,
173 init_data, pmic);
174 if (IS_ERR(pmic->rdev[i])) {
175 dev_err(&i2c->dev, "failed to register %s\n", id->name);
176 err = PTR_ERR(pmic->rdev[i]);
177 goto error;
181 i2c_set_clientdata(i2c, pmic);
183 return 0;
185 error:
186 while (--i >= 0)
187 regulator_unregister(pmic->rdev[i]);
189 kfree(pmic);
190 return err;
193 static int __devexit isl6271a_remove(struct i2c_client *i2c)
195 struct isl_pmic *pmic = i2c_get_clientdata(i2c);
196 int i;
198 for (i = 0; i < 3; i++)
199 regulator_unregister(pmic->rdev[i]);
201 kfree(pmic);
203 return 0;
206 static const struct i2c_device_id isl6271a_id[] = {
207 {.name = "isl6271a", 0 },
208 { },
211 MODULE_DEVICE_TABLE(i2c, isl6271a_id);
213 static struct i2c_driver isl6271a_i2c_driver = {
214 .driver = {
215 .name = "isl6271a",
216 .owner = THIS_MODULE,
218 .probe = isl6271a_probe,
219 .remove = __devexit_p(isl6271a_remove),
220 .id_table = isl6271a_id,
223 static int __init isl6271a_init(void)
225 return i2c_add_driver(&isl6271a_i2c_driver);
228 static void __exit isl6271a_cleanup(void)
230 i2c_del_driver(&isl6271a_i2c_driver);
233 subsys_initcall(isl6271a_init);
234 module_exit(isl6271a_cleanup);
236 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
237 MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
238 MODULE_LICENSE("GPL v2");