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/delay.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/regulator/driver.h>
  30 #include <linux/regulator/machine.h>
  31 #include <linux/mfd/aat2870.h>
  32
  33 struct aat2870_regulator {
  34         struct platform_device *pdev;
  35         struct regulator_desc desc;
  36
  37         const int *voltages; /* uV */
  38
  39         int min_uV;
  40         int max_uV;
  41
  42         u8 enable_addr;
  43         u8 enable_shift;
  44         u8 enable_mask;
  45
  46         u8 voltage_addr;
  47         u8 voltage_shift;
  48         u8 voltage_mask;
  49 };
  50
  51 static int aat2870_ldo_list_voltage(struct regulator_dev *rdev,
  52                                     unsigned selector)
  53 {
  54         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  55
  56         return ri->voltages[selector];
  57 }
  58
  59 static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
  60                                        unsigned selector)
  61 {
  62         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  63         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  64
  65         return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
  66                         (selector << ri->voltage_shift) & ri->voltage_mask);
  67 }
  68
  69 static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
  70 {
  71         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  72         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  73         u8 val;
  74         int ret;
  75
  76         ret = aat2870->read(aat2870, ri->voltage_addr, &val);
  77         if (ret)
  78                 return ret;
  79
  80         return (val & ri->voltage_mask) >> ri->voltage_shift;
  81 }
  82
  83 static int aat2870_ldo_enable(struct regulator_dev *rdev)
  84 {
  85         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  86         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  87
  88         return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
  89                                ri->enable_mask);
  90 }
  91
  92 static int aat2870_ldo_disable(struct regulator_dev *rdev)
  93 {
  94         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
  95         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
  96
  97         return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
  98 }
  99
 100 static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
 101 {
 102         struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
 103         struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
 104         u8 val;
 105         int ret;
 106
 107         ret = aat2870->read(aat2870, ri->enable_addr, &val);
 108         if (ret)
 109                 return ret;
 110
 111         return val & ri->enable_mask ? 1 : 0;
 112 }
 113
 114 static struct regulator_ops aat2870_ldo_ops = {
 115         .list_voltage = aat2870_ldo_list_voltage,
 116         .set_voltage_sel = aat2870_ldo_set_voltage_sel,
 117         .get_voltage_sel = aat2870_ldo_get_voltage_sel,
 118         .enable = aat2870_ldo_enable,
 119         .disable = aat2870_ldo_disable,
 120         .is_enabled = aat2870_ldo_is_enabled,
 121 };
 122
 123 static const int aat2870_ldo_voltages[] = {
 124         1200000, 1300000, 1500000, 1600000,
 125         1800000, 2000000, 2200000, 2500000,
 126         2600000, 2700000, 2800000, 2900000,
 127         3000000, 3100000, 3200000, 3300000,
 128 };
 129
 130 #define AAT2870_LDO(ids)                                \
 131         {                                               \
 132                 .desc = {                               \
 133                         .name = #ids,                   \
 134                         .id = AAT2870_ID_##ids,         \
 135                         .n_voltages = ARRAY_SIZE(aat2870_ldo_voltages), \
 136                         .ops = &aat2870_ldo_ops,        \
 137                         .type = REGULATOR_VOLTAGE,      \
 138                         .owner = THIS_MODULE,           \
 139                 },                                      \
 140                 .voltages = aat2870_ldo_voltages,       \
 141                 .min_uV = 1200000,                      \
 142                 .max_uV = 3300000,                      \
 143         }
 144
 145 static struct aat2870_regulator aat2870_regulators[] = {
 146         AAT2870_LDO(LDOA),
 147         AAT2870_LDO(LDOB),
 148         AAT2870_LDO(LDOC),
 149         AAT2870_LDO(LDOD),
 150 };
 151
 152 static struct aat2870_regulator *aat2870_get_regulator(int id)
 153 {
 154         struct aat2870_regulator *ri = NULL;
 155         int i;
 156
 157         for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
 158                 ri = &aat2870_regulators[i];
 159                 if (ri->desc.id == id)
 160                         break;
 161         }
 162
 163         if (i == ARRAY_SIZE(aat2870_regulators))
 164                 return NULL;
 165
 166         ri->enable_addr = AAT2870_LDO_EN;
 167         ri->enable_shift = id - AAT2870_ID_LDOA;
 168         ri->enable_mask = 0x1 << ri->enable_shift;
 169
 170         ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
 171                            AAT2870_LDO_CD : AAT2870_LDO_AB;
 172         ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
 173         ri->voltage_mask = 0xF << ri->voltage_shift;
 174
 175         return ri;
 176 }
 177
 178 static int aat2870_regulator_probe(struct platform_device *pdev)
 179 {
 180         struct aat2870_regulator *ri;
 181         struct regulator_dev *rdev;
 182
 183         ri = aat2870_get_regulator(pdev->id);
 184         if (!ri) {
 185                 dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
 186                 return -EINVAL;
 187         }
 188         ri->pdev = pdev;
 189
 190         rdev = regulator_register(&ri->desc, &pdev->dev,
 191                                   pdev->dev.platform_data, ri);
 192         if (IS_ERR(rdev)) {
 193                 dev_err(&pdev->dev, "Failed to register regulator %s\n",
 194                         ri->desc.name);
 195                 return PTR_ERR(rdev);
 196         }
 197         platform_set_drvdata(pdev, rdev);
 198
 199         return 0;
 200 }
 201
 202 static int __devexit aat2870_regulator_remove(struct platform_device *pdev)
 203 {
 204         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 205
 206         regulator_unregister(rdev);
 207         return 0;
 208 }
 209
 210 static struct platform_driver aat2870_regulator_driver = {
 211         .driver = {
 212                 .name   = "aat2870-regulator",
 213                 .owner  = THIS_MODULE,
 214         },
 215         .probe  = aat2870_regulator_probe,
 216         .remove = __devexit_p(aat2870_regulator_remove),
 217 };
 218
 219 static int __init aat2870_regulator_init(void)
 220 {
 221         return platform_driver_register(&aat2870_regulator_driver);
 222 }
 223 subsys_initcall(aat2870_regulator_init);
 224
 225 static void __exit aat2870_regulator_exit(void)
 226 {
 227         platform_driver_unregister(&aat2870_regulator_driver);
 228 }
 229 module_exit(aat2870_regulator_exit);
 230
 231 MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
 232 MODULE_LICENSE("GPL");
 233 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");