drivers/regulator/isl6271a-regulator.c

   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 struct regulator_ops isl_fixed_ops = {
  77         .list_voltage   = regulator_list_voltage_linear,
  78 };
  79
  80 static 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
 109 static 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   = i2c->dev.platform_data;
 114         struct isl_pmic *pmic;
 115         int err, 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 = 0;
 134                 config.driver_data = pmic;
 135
 136                 pmic->rdev[i] = regulator_register(&isl_rd[i], &config);
 137                 if (IS_ERR(pmic->rdev[i])) {
 138                         dev_err(&i2c->dev, "failed to register %s\n", id->name);
 139                         err = PTR_ERR(pmic->rdev[i]);
 140                         goto error;
 141                 }
 142         }
 143
 144         i2c_set_clientdata(i2c, pmic);
 145
 146         return 0;
 147
 148 error:
 149         while (--i >= 0)
 150                 regulator_unregister(pmic->rdev[i]);
 151         return err;
 152 }
 153
 154 static int isl6271a_remove(struct i2c_client *i2c)
 155 {
 156         struct isl_pmic *pmic = i2c_get_clientdata(i2c);
 157         int i;
 158
 159         for (i = 0; i < 3; i++)
 160                 regulator_unregister(pmic->rdev[i]);
 161         return 0;
 162 }
 163
 164 static const struct i2c_device_id isl6271a_id[] = {
 165         {.name = "isl6271a", 0 },
 166         { },
 167 };
 168
 169 MODULE_DEVICE_TABLE(i2c, isl6271a_id);
 170
 171 static struct i2c_driver isl6271a_i2c_driver = {
 172         .driver = {
 173                 .name = "isl6271a",
 174                 .owner = THIS_MODULE,
 175         },
 176         .probe = isl6271a_probe,
 177         .remove = isl6271a_remove,
 178         .id_table = isl6271a_id,
 179 };
 180
 181 static int __init isl6271a_init(void)
 182 {
 183         return i2c_add_driver(&isl6271a_i2c_driver);
 184 }
 185
 186 static void __exit isl6271a_cleanup(void)
 187 {
 188         i2c_del_driver(&isl6271a_i2c_driver);
 189 }
 190
 191 subsys_initcall(isl6271a_init);
 192 module_exit(isl6271a_cleanup);
 193
 194 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
 195 MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
 196 MODULE_LICENSE("GPL v2");