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/slab.h>
  26 #include <linux/delay.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 platform_device *pdev;
  34         struct regulator_desc desc;
  35
  36         const int *voltages; /* uV */
  37
  38         int min_uV;
  39         int max_uV;
  40
  41         u8 enable_addr;
  42         u8 enable_shift;
  43         u8 enable_mask;
  44
  45         u8 voltage_addr;
  46         u8 voltage_shift;
  47         u8 voltage_mask;
  48 };
  49
  50 static int aat2870_ldo_list_voltage(struct regulator_dev *rdev,
  51                                     unsigned selector)
  52 {
  53         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  54
  55         return ri->voltages[selector];
  56 }
  57
  58 static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
  59                                        unsigned selector)
  60 {
  61         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  62         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  63
  64         return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
  65                         (selector << ri->voltage_shift) & ri->voltage_mask);
  66 }
  67
  68 static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
  69 {
  70         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  71         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  72         u8 val;
  73         int ret;
  74
  75         ret = aat2870->read(aat2870, ri->voltage_addr, &val);
  76         if (ret)
  77                 return ret;
  78
  79         return (val & ri->voltage_mask) >> ri->voltage_shift;
  80 }
  81
  82 static int aat2870_ldo_enable(struct regulator_dev *rdev)
  83 {
  84         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  85         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  86
  87         return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
  88                                ri->enable_mask);
  89 }
  90
  91 static int aat2870_ldo_disable(struct regulator_dev *rdev)
  92 {
  93         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  94         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  95
  96         return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
  97 }
  98
  99 static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
 100 {
 101         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
 102         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
 103         u8 val;
 104         int ret;
 105
 106         ret = aat2870->read(aat2870, ri->enable_addr, &val);
 107         if (ret)
 108                 return ret;
 109
 110         return val & ri->enable_mask ? 1 : 0;
 111 }
 112
 113 static struct regulator_ops aat2870_ldo_ops = {
 114         .list_voltage = aat2870_ldo_list_voltage,
 115         .set_voltage_sel = aat2870_ldo_set_voltage_sel,
 116         .get_voltage_sel = aat2870_ldo_get_voltage_sel,
 117         .enable = aat2870_ldo_enable,
 118         .disable = aat2870_ldo_disable,
 119         .is_enabled = aat2870_ldo_is_enabled,
 120 };
 121
 122 static const int aat2870_ldo_voltages[] = {
 123         1200000, 1300000, 1500000, 1600000,
 124         1800000, 2000000, 2200000, 2500000,
 125         2600000, 2700000, 2800000, 2900000,
 126         3000000, 3100000, 3200000, 3300000,
 127 };
 128
 129 #define AAT2870_LDO(ids)                                \
 130         {                                               \
 131                 .desc = {                               \
 132                         .name = #ids,                   \
 133                         .id = AAT2870_ID_##ids,         \
 134                         .n_voltages = ARRAY_SIZE(aat2870_ldo_voltages), \
 135                         .ops = &aat2870_ldo_ops,        \
 136                         .type = REGULATOR_VOLTAGE,      \
 137                         .owner = THIS_MODULE,           \
 138                 },                                      \
 139                 .voltages = aat2870_ldo_voltages,       \
 140                 .min_uV = 1200000,                      \
 141                 .max_uV = 3300000,                      \
 142         }
 143
 144 static struct aat2870_regulator aat2870_regulators[] = {
 145         AAT2870_LDO(LDOA),
 146         AAT2870_LDO(LDOB),
 147         AAT2870_LDO(LDOC),
 148         AAT2870_LDO(LDOD),
 149 };
 150
 151 static struct aat2870_regulator *aat2870_get_regulator(int id)
 152 {
 153         struct aat2870_regulator *ri = NULL;
 154         int i;
 155
 156         for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
 157                 ri = &aat2870_regulators[i];
 158                 if (ri->desc.id == id)
 159                         break;
 160         }
 161
 162         if (!ri)
 163                 return NULL;
 164
 165         ri->enable_addr = AAT2870_LDO_EN;
 166         ri->enable_shift = id - AAT2870_ID_LDOA;
 167         ri->enable_mask = 0x1 << ri->enable_shift;
 168
 169         ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
 170                            AAT2870_LDO_CD : AAT2870_LDO_AB;
 171         ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
 172         ri->voltage_mask = 0xF << ri->voltage_shift;
 173
 174         return ri;
 175 }
 176
 177 static int aat2870_regulator_probe(struct platform_device *pdev)
 178 {
 179         struct aat2870_regulator *ri;
 180         struct regulator_dev *rdev;
 181
 182         ri = aat2870_get_regulator(pdev->id);
 183         if (!ri) {
 184                 dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
 185                 return -EINVAL;
 186         }
 187         ri->pdev = pdev;
 188
 189         rdev = regulator_register(&ri->desc, &pdev->dev,
 190                                   pdev->dev.platform_data, ri);
 191         if (IS_ERR(rdev)) {
 192                 dev_err(&pdev->dev, "Failed to register regulator %s\n",
 193                         ri->desc.name);
 194                 return PTR_ERR(rdev);
 195         }
 196         platform_set_drvdata(pdev, rdev);
 197
 198         return 0;
 199 }
 200
 201 static int __devexit aat2870_regulator_remove(struct platform_device *pdev)
 202 {
 203         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 204
 205         regulator_unregister(rdev);
 206         return 0;
 207 }
 208
 209 static struct platform_driver aat2870_regulator_driver = {
 210         .driver = {
 211                 .name   = "aat2870-regulator",
 212                 .owner  = THIS_MODULE,
 213         },
 214         .probe  = aat2870_regulator_probe,
 215         .remove = __devexit_p(aat2870_regulator_remove),
 216 };
 217
 218 static int __init aat2870_regulator_init(void)
 219 {
 220         return platform_driver_register(&aat2870_regulator_driver);
 221 }
 222 subsys_initcall(aat2870_regulator_init);
 223
 224 static void __exit aat2870_regulator_exit(void)
 225 {
 226         platform_driver_unregister(&aat2870_regulator_driver);
 227 }
 228 module_exit(aat2870_regulator_exit);
 229
 230 MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
 231 MODULE_LICENSE("GPL");
 232 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");