drivers/regulator/aat2870-regulator.c

   1 /*
   2  * linux/drivers/regulator/aat2870-regulator.c
   3  *
   4  * Copyright (c) 2011, NVIDIA Corporation.
   5  * Author: Jin Park <jinyoungp@nvidia.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * version 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  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., 51 Franklin St, Fifth Floor, Boston, MA
  19  * 02110-1301 USA
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/init.h>
  24 #include <linux/err.h>
  25 #include <linux/module.h>
  26 #include <linux/slab.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/regulator/driver.h>
  29 #include <linux/regulator/machine.h>
  30 #include <linux/mfd/aat2870.h>
  31
  32 struct aat2870_regulator {
  33         struct aat2870_data *aat2870;
  34         struct regulator_desc desc;
  35
  36         u8 enable_addr;
  37         u8 enable_shift;
  38         u8 enable_mask;
  39
  40         u8 voltage_addr;
  41         u8 voltage_shift;
  42         u8 voltage_mask;
  43 };
  44
  45 static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
  46                                        unsigned selector)
  47 {
  48         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  49         struct aat2870_data *aat2870 = ri->aat2870;
  50
  51         return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
  52                                selector << ri->voltage_shift);
  53 }
  54
  55 static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
  56 {
  57         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  58         struct aat2870_data *aat2870 = ri->aat2870;
  59         u8 val;
  60         int ret;
  61
  62         ret = aat2870->read(aat2870, ri->voltage_addr, &val);
  63         if (ret)
  64                 return ret;
  65
  66         return (val & ri->voltage_mask) >> ri->voltage_shift;
  67 }
  68
  69 static int aat2870_ldo_enable(struct regulator_dev *rdev)
  70 {
  71         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  72         struct aat2870_data *aat2870 = ri->aat2870;
  73
  74         return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
  75                                ri->enable_mask);
  76 }
  77
  78 static int aat2870_ldo_disable(struct regulator_dev *rdev)
  79 {
  80         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  81         struct aat2870_data *aat2870 = ri->aat2870;
  82
  83         return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
  84 }
  85
  86 static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
  87 {
  88         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  89         struct aat2870_data *aat2870 = ri->aat2870;
  90         u8 val;
  91         int ret;
  92
  93         ret = aat2870->read(aat2870, ri->enable_addr, &val);
  94         if (ret)
  95                 return ret;
  96
  97         return val & ri->enable_mask ? 1 : 0;
  98 }
  99
 100 static struct regulator_ops aat2870_ldo_ops = {
 101         .list_voltage = regulator_list_voltage_table,
 102         .set_voltage_sel = aat2870_ldo_set_voltage_sel,
 103         .get_voltage_sel = aat2870_ldo_get_voltage_sel,
 104         .enable = aat2870_ldo_enable,
 105         .disable = aat2870_ldo_disable,
 106         .is_enabled = aat2870_ldo_is_enabled,
 107 };
 108
 109 static const unsigned int aat2870_ldo_voltages[] = {
 110         1200000, 1300000, 1500000, 1600000,
 111         1800000, 2000000, 2200000, 2500000,
 112         2600000, 2700000, 2800000, 2900000,
 113         3000000, 3100000, 3200000, 3300000,
 114 };
 115
 116 #define AAT2870_LDO(ids)                                \
 117         {                                               \
 118                 .desc = {                               \
 119                         .name = #ids,                   \
 120                         .id = AAT2870_ID_##ids,         \
 121                         .n_voltages = ARRAY_SIZE(aat2870_ldo_voltages), \
 122                         .volt_table = aat2870_ldo_voltages, \
 123                         .ops = &aat2870_ldo_ops,        \
 124                         .type = REGULATOR_VOLTAGE,      \
 125                         .owner = THIS_MODULE,           \
 126                 },                                      \
 127         }
 128
 129 static struct aat2870_regulator aat2870_regulators[] = {
 130         AAT2870_LDO(LDOA),
 131         AAT2870_LDO(LDOB),
 132         AAT2870_LDO(LDOC),
 133         AAT2870_LDO(LDOD),
 134 };
 135
 136 static struct aat2870_regulator *aat2870_get_regulator(int id)
 137 {
 138         struct aat2870_regulator *ri = NULL;
 139         int i;
 140
 141         for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
 142                 ri = &aat2870_regulators[i];
 143                 if (ri->desc.id == id)
 144                         break;
 145         }
 146
 147         if (i == ARRAY_SIZE(aat2870_regulators))
 148                 return NULL;
 149
 150         ri->enable_addr = AAT2870_LDO_EN;
 151         ri->enable_shift = id - AAT2870_ID_LDOA;
 152         ri->enable_mask = 0x1 << ri->enable_shift;
 153
 154         ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
 155                            AAT2870_LDO_CD : AAT2870_LDO_AB;
 156         ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
 157         ri->voltage_mask = 0xF << ri->voltage_shift;
 158
 159         return ri;
 160 }
 161
 162 static int aat2870_regulator_probe(struct platform_device *pdev)
 163 {
 164         struct aat2870_regulator *ri;
 165         struct regulator_config config = { };
 166         struct regulator_dev *rdev;
 167
 168         ri = aat2870_get_regulator(pdev->id);
 169         if (!ri) {
 170                 dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
 171                 return -EINVAL;
 172         }
 173         ri->aat2870 = dev_get_drvdata(pdev->dev.parent);
 174
 175         config.dev = &pdev->dev;
 176         config.driver_data = ri;
 177         config.init_data = pdev->dev.platform_data;
 178
 179         rdev = regulator_register(&ri->desc, &config);
 180         if (IS_ERR(rdev)) {
 181                 dev_err(&pdev->dev, "Failed to register regulator %s\n",
 182                         ri->desc.name);
 183                 return PTR_ERR(rdev);
 184         }
 185         platform_set_drvdata(pdev, rdev);
 186
 187         return 0;
 188 }
 189
 190 static int aat2870_regulator_remove(struct platform_device *pdev)
 191 {
 192         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 193
 194         regulator_unregister(rdev);
 195         return 0;
 196 }
 197
 198 static struct platform_driver aat2870_regulator_driver = {
 199         .driver = {
 200                 .name   = "aat2870-regulator",
 201                 .owner  = THIS_MODULE,
 202         },
 203         .probe  = aat2870_regulator_probe,
 204         .remove = aat2870_regulator_remove,
 205 };
 206
 207 static int __init aat2870_regulator_init(void)
 208 {
 209         return platform_driver_register(&aat2870_regulator_driver);
 210 }
 211 subsys_initcall(aat2870_regulator_init);
 212
 213 static void __exit aat2870_regulator_exit(void)
 214 {
 215         platform_driver_unregister(&aat2870_regulator_driver);
 216 }
 217 module_exit(aat2870_regulator_exit);
 218
 219 MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
 220 MODULE_LICENSE("GPL");
 221 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
 222 MODULE_ALIAS("platform:aat2870-regulator");