2 * max1586.c -- Voltage and current regulation for the Maxim 1586
4 * Copyright (C) 2008 Robert Jarzmik
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include <linux/module.h>
21 #include <linux/err.h>
22 #include <linux/i2c.h>
23 #include <linux/platform_device.h>
24 #include <linux/regulator/driver.h>
25 #include <linux/regulator/max1586.h>
27 #define MAX1586_V3_MAX_VSEL 31
28 #define MAX1586_V6_MAX_VSEL 3
30 #define MAX1586_V3_MIN_UV 700000
31 #define MAX1586_V3_MAX_UV 1475000
32 #define MAX1586_V3_STEP_UV 25000
34 #define MAX1586_V6_MIN_UV 0
35 #define MAX1586_V6_MAX_UV 3000000
37 #define I2C_V3_SELECT (0 << 5)
38 #define I2C_V6_SELECT (1 << 5)
42 * On I2C bus, sending a "x" byte to the max1586 means :
43 * set V3 to 0.700V + (x & 0x1f) * 0.025V
45 static int max1586_v3_calc_voltage(unsigned selector)
47 return MAX1586_V3_MIN_UV + (MAX1586_V3_STEP_UV * selector);
50 static int max1586_v3_set(struct regulator_dev *rdev, int min_uV, int max_uV)
52 struct i2c_client *client = rdev_get_drvdata(rdev);
56 if (min_uV < MAX1586_V3_MIN_UV || min_uV > MAX1586_V3_MAX_UV)
58 if (max_uV < MAX1586_V3_MIN_UV || max_uV > MAX1586_V3_MAX_UV)
61 selector = (min_uV - MAX1586_V3_MIN_UV) / MAX1586_V3_STEP_UV;
62 if (max1586_v3_calc_voltage(selector) > max_uV)
65 dev_dbg(&client->dev, "changing voltage v3 to %dmv\n",
66 max1586_v3_calc_voltage(selector) / 1000);
68 v3_prog = I2C_V3_SELECT | (u8) selector;
69 return i2c_smbus_write_byte(client, v3_prog);
72 static int max1586_v3_list(struct regulator_dev *rdev, unsigned selector)
74 if (selector > MAX1586_V3_MAX_VSEL)
76 return max1586_v3_calc_voltage(selector);
81 * On I2C bus, sending a "x" byte to the max1586 means :
82 * set V6 to either 0V, 1.8V, 2.5V, 3V depending on (x & 0x3)
83 * As regulator framework doesn't accept voltages to be 0V, we use 1uV.
85 static int max1586_v6_calc_voltage(unsigned selector)
87 static int voltages_uv[] = { 1, 1800000, 2500000, 3000000 };
89 return voltages_uv[selector];
92 static int max1586_v6_set(struct regulator_dev *rdev, int min_uV, int max_uV)
94 struct i2c_client *client = rdev_get_drvdata(rdev);
98 if (min_uV < MAX1586_V6_MIN_UV || min_uV > MAX1586_V6_MAX_UV)
100 if (max_uV < MAX1586_V6_MIN_UV || max_uV > MAX1586_V6_MAX_UV)
103 if (min_uV >= 3000000)
105 if (min_uV < 3000000)
107 if (min_uV < 2500000)
109 if (min_uV < 1800000)
112 if (max1586_v6_calc_voltage(selector) > max_uV)
115 dev_dbg(&client->dev, "changing voltage v6 to %dmv\n",
116 max1586_v6_calc_voltage(selector) / 1000);
118 v6_prog = I2C_V6_SELECT | (u8) selector;
119 return i2c_smbus_write_byte(client, v6_prog);
122 static int max1586_v6_list(struct regulator_dev *rdev, unsigned selector)
124 if (selector > MAX1586_V6_MAX_VSEL)
126 return max1586_v6_calc_voltage(selector);
130 * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back
133 static struct regulator_ops max1586_v3_ops = {
134 .set_voltage = max1586_v3_set,
135 .list_voltage = max1586_v3_list,
138 static struct regulator_ops max1586_v6_ops = {
139 .set_voltage = max1586_v6_set,
140 .list_voltage = max1586_v6_list,
143 static struct regulator_desc max1586_reg[] = {
147 .ops = &max1586_v3_ops,
148 .type = REGULATOR_VOLTAGE,
149 .n_voltages = MAX1586_V3_MAX_VSEL + 1,
150 .owner = THIS_MODULE,
155 .ops = &max1586_v6_ops,
156 .type = REGULATOR_VOLTAGE,
157 .n_voltages = MAX1586_V6_MAX_VSEL + 1,
158 .owner = THIS_MODULE,
162 static int max1586_pmic_probe(struct i2c_client *client,
163 const struct i2c_device_id *i2c_id)
165 struct regulator_dev **rdev;
166 struct max1586_platform_data *pdata = client->dev.platform_data;
169 rdev = kzalloc(sizeof(struct regulator_dev *) * (MAX1586_V6 + 1),
175 for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) {
176 id = pdata->subdevs[i].id;
177 if (!pdata->subdevs[i].platform_data)
179 if (id < MAX1586_V3 || id > MAX1586_V6) {
180 dev_err(&client->dev, "invalid regulator id %d\n", id);
183 rdev[i] = regulator_register(&max1586_reg[id], &client->dev,
184 pdata->subdevs[i].platform_data,
186 if (IS_ERR(rdev[i])) {
187 ret = PTR_ERR(rdev[i]);
188 dev_err(&client->dev, "failed to register %s\n",
189 max1586_reg[id].name);
194 i2c_set_clientdata(client, rdev);
195 dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n");
200 regulator_unregister(rdev[i]);
205 static int max1586_pmic_remove(struct i2c_client *client)
207 struct regulator_dev **rdev = i2c_get_clientdata(client);
210 for (i = 0; i <= MAX1586_V6; i++)
212 regulator_unregister(rdev[i]);
214 i2c_set_clientdata(client, NULL);
219 static const struct i2c_device_id max1586_id[] = {
223 MODULE_DEVICE_TABLE(i2c, max1586_id);
225 static struct i2c_driver max1586_pmic_driver = {
226 .probe = max1586_pmic_probe,
227 .remove = max1586_pmic_remove,
231 .id_table = max1586_id,
234 static int __init max1586_pmic_init(void)
236 return i2c_add_driver(&max1586_pmic_driver);
238 subsys_initcall(max1586_pmic_init);
240 static void __exit max1586_pmic_exit(void)
242 i2c_del_driver(&max1586_pmic_driver);
244 module_exit(max1586_pmic_exit);
246 /* Module information */
247 MODULE_DESCRIPTION("MAXIM 1586 voltage regulator driver");
248 MODULE_AUTHOR("Robert Jarzmik");
249 MODULE_LICENSE("GPL");