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