drivers/regulator/da9210-regulator.c

   1 /*
   2  * da9210-regulator.c - Regulator device driver for DA9210
   3  * Copyright (C) 2013  Dialog Semiconductor Ltd.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Library General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Library General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Library General Public
  16  * License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
  18  * Boston, MA  02110-1301, USA.
  19  */
  20
  21 #include <linux/err.h>
  22 #include <linux/i2c.h>
  23 #include <linux/module.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/irq.h>
  26 #include <linux/regulator/driver.h>
  27 #include <linux/regulator/machine.h>
  28 #include <linux/of_device.h>
  29 #include <linux/regulator/of_regulator.h>
  30 #include <linux/regmap.h>
  31
  32 #include "da9210-regulator.h"
  33
  34 struct da9210 {
  35         struct regulator_dev *rdev;
  36         struct regmap *regmap;
  37 };
  38
  39 static const struct regmap_config da9210_regmap_config = {
  40         .reg_bits = 8,
  41         .val_bits = 8,
  42 };
  43
  44 static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA,
  45                                     int max_uA);
  46 static int da9210_get_current_limit(struct regulator_dev *rdev);
  47
  48 static const struct regulator_ops da9210_buck_ops = {
  49         .enable = regulator_enable_regmap,
  50         .disable = regulator_disable_regmap,
  51         .is_enabled = regulator_is_enabled_regmap,
  52         .set_voltage_sel = regulator_set_voltage_sel_regmap,
  53         .get_voltage_sel = regulator_get_voltage_sel_regmap,
  54         .list_voltage = regulator_list_voltage_linear,
  55         .set_current_limit = da9210_set_current_limit,
  56         .get_current_limit = da9210_get_current_limit,
  57 };
  58
  59 /* Default limits measured in millivolts and milliamps */
  60 #define DA9210_MIN_MV           300
  61 #define DA9210_MAX_MV           1570
  62 #define DA9210_STEP_MV          10
  63
  64 /* Current limits for buck (uA) indices corresponds with register values */
  65 static const int da9210_buck_limits[] = {
  66         1600000, 1800000, 2000000, 2200000, 2400000, 2600000, 2800000, 3000000,
  67         3200000, 3400000, 3600000, 3800000, 4000000, 4200000, 4400000, 4600000
  68 };
  69
  70 static const struct regulator_desc da9210_reg = {
  71         .name = "DA9210",
  72         .id = 0,
  73         .ops = &da9210_buck_ops,
  74         .type = REGULATOR_VOLTAGE,
  75         .n_voltages = ((DA9210_MAX_MV - DA9210_MIN_MV) / DA9210_STEP_MV) + 1,
  76         .min_uV = (DA9210_MIN_MV * 1000),
  77         .uV_step = (DA9210_STEP_MV * 1000),
  78         .vsel_reg = DA9210_REG_VBUCK_A,
  79         .vsel_mask = DA9210_VBUCK_MASK,
  80         .enable_reg = DA9210_REG_BUCK_CONT,
  81         .enable_mask = DA9210_BUCK_EN,
  82         .owner = THIS_MODULE,
  83 };
  84
  85 static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA,
  86                                     int max_uA)
  87 {
  88         struct da9210 *chip = rdev_get_drvdata(rdev);
  89         unsigned int sel;
  90         int i;
  91
  92         /* search for closest to maximum */
  93         for (i = ARRAY_SIZE(da9210_buck_limits)-1; i >= 0; i--) {
  94                 if (min_uA <= da9210_buck_limits[i] &&
  95                     max_uA >= da9210_buck_limits[i]) {
  96                         sel = i;
  97                         sel = sel << DA9210_BUCK_ILIM_SHIFT;
  98                         return regmap_update_bits(chip->regmap,
  99                                                   DA9210_REG_BUCK_ILIM,
 100                                                   DA9210_BUCK_ILIM_MASK, sel);
 101                 }
 102         }
 103
 104         return -EINVAL;
 105 }
 106
 107 static int da9210_get_current_limit(struct regulator_dev *rdev)
 108 {
 109         struct da9210 *chip = rdev_get_drvdata(rdev);
 110         unsigned int data;
 111         unsigned int sel;
 112         int ret;
 113
 114         ret = regmap_read(chip->regmap, DA9210_REG_BUCK_ILIM, &data);
 115         if (ret < 0)
 116                 return ret;
 117
 118         /* select one of 16 values: 0000 (1600mA) to 1111 (4600mA) */
 119         sel = (data & DA9210_BUCK_ILIM_MASK) >> DA9210_BUCK_ILIM_SHIFT;
 120
 121         return da9210_buck_limits[sel];
 122 }
 123
 124 static irqreturn_t da9210_irq_handler(int irq, void *data)
 125 {
 126         struct da9210 *chip = data;
 127         unsigned int val, handled = 0;
 128         int error, ret = IRQ_NONE;
 129
 130         error = regmap_read(chip->regmap, DA9210_REG_EVENT_B, &val);
 131         if (error < 0)
 132                 goto error_i2c;
 133
 134         mutex_lock(&chip->rdev->mutex);
 135
 136         if (val & DA9210_E_OVCURR) {
 137                 regulator_notifier_call_chain(chip->rdev,
 138                                               REGULATOR_EVENT_OVER_CURRENT,
 139                                               NULL);
 140                 handled |= DA9210_E_OVCURR;
 141         }
 142         if (val & DA9210_E_NPWRGOOD) {
 143                 regulator_notifier_call_chain(chip->rdev,
 144                                               REGULATOR_EVENT_UNDER_VOLTAGE,
 145                                               NULL);
 146                 handled |= DA9210_E_NPWRGOOD;
 147         }
 148         if (val & (DA9210_E_TEMP_WARN | DA9210_E_TEMP_CRIT)) {
 149                 regulator_notifier_call_chain(chip->rdev,
 150                                               REGULATOR_EVENT_OVER_TEMP, NULL);
 151                 handled |= val & (DA9210_E_TEMP_WARN | DA9210_E_TEMP_CRIT);
 152         }
 153         if (val & DA9210_E_VMAX) {
 154                 regulator_notifier_call_chain(chip->rdev,
 155                                               REGULATOR_EVENT_REGULATION_OUT,
 156                                               NULL);
 157                 handled |= DA9210_E_VMAX;
 158         }
 159
 160         mutex_unlock(&chip->rdev->mutex);
 161
 162         if (handled) {
 163                 /* Clear handled events */
 164                 error = regmap_write(chip->regmap, DA9210_REG_EVENT_B, handled);
 165                 if (error < 0)
 166                         goto error_i2c;
 167
 168                 ret = IRQ_HANDLED;
 169         }
 170
 171         return ret;
 172
 173 error_i2c:
 174         dev_err(regmap_get_device(chip->regmap), "I2C error : %d\n", error);
 175         return ret;
 176 }
 177
 178 /*
 179  * I2C driver interface functions
 180  */
 181
 182 static const struct of_device_id da9210_dt_ids[] = {
 183         { .compatible = "dlg,da9210", },
 184         { }
 185 };
 186 MODULE_DEVICE_TABLE(of, da9210_dt_ids);
 187
 188 static int da9210_i2c_probe(struct i2c_client *i2c,
 189                             const struct i2c_device_id *id)
 190 {
 191         struct da9210 *chip;
 192         struct device *dev = &i2c->dev;
 193         struct da9210_pdata *pdata = dev_get_platdata(dev);
 194         struct regulator_dev *rdev = NULL;
 195         struct regulator_config config = { };
 196         int error;
 197         const struct of_device_id *match;
 198
 199         if (i2c->dev.of_node && !pdata) {
 200                 match = of_match_device(of_match_ptr(da9210_dt_ids),
 201                                                 &i2c->dev);
 202                 if (!match) {
 203                         dev_err(&i2c->dev, "Error: No device match found\n");
 204                         return -ENODEV;
 205                 }
 206         }
 207
 208         chip = devm_kzalloc(&i2c->dev, sizeof(struct da9210), GFP_KERNEL);
 209         if (!chip)
 210                 return -ENOMEM;
 211
 212         chip->regmap = devm_regmap_init_i2c(i2c, &da9210_regmap_config);
 213         if (IS_ERR(chip->regmap)) {
 214                 error = PTR_ERR(chip->regmap);
 215                 dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
 216                         error);
 217                 return error;
 218         }
 219
 220         config.dev = &i2c->dev;
 221         config.init_data = pdata ? &pdata->da9210_constraints :
 222                 of_get_regulator_init_data(dev, dev->of_node, &da9210_reg);
 223         config.driver_data = chip;
 224         config.regmap = chip->regmap;
 225         config.of_node = dev->of_node;
 226
 227         /* Mask all interrupt sources to deassert interrupt line */
 228         error = regmap_write(chip->regmap, DA9210_REG_MASK_A, ~0);
 229         if (!error)
 230                 error = regmap_write(chip->regmap, DA9210_REG_MASK_B, ~0);
 231         if (error) {
 232                 dev_err(&i2c->dev, "Failed to write to mask reg: %d\n", error);
 233                 return error;
 234         }
 235
 236         rdev = devm_regulator_register(&i2c->dev, &da9210_reg, &config);
 237         if (IS_ERR(rdev)) {
 238                 dev_err(&i2c->dev, "Failed to register DA9210 regulator\n");
 239                 return PTR_ERR(rdev);
 240         }
 241
 242         chip->rdev = rdev;
 243         if (i2c->irq) {
 244                 error = devm_request_threaded_irq(&i2c->dev, i2c->irq, NULL,
 245                                                   da9210_irq_handler,
 246                                                   IRQF_TRIGGER_LOW |
 247                                                   IRQF_ONESHOT | IRQF_SHARED,
 248                                                   "da9210", chip);
 249                 if (error) {
 250                         dev_err(&i2c->dev, "Failed to request IRQ%u: %d\n",
 251                                 i2c->irq, error);
 252                         return error;
 253                 }
 254
 255                 error = regmap_update_bits(chip->regmap, DA9210_REG_MASK_B,
 256                                          DA9210_M_OVCURR | DA9210_M_NPWRGOOD |
 257                                          DA9210_M_TEMP_WARN |
 258                                          DA9210_M_TEMP_CRIT | DA9210_M_VMAX, 0);
 259                 if (error < 0) {
 260                         dev_err(&i2c->dev, "Failed to update mask reg: %d\n",
 261                                 error);
 262                         return error;
 263                 }
 264         } else {
 265                 dev_warn(&i2c->dev, "No IRQ configured\n");
 266         }
 267
 268         i2c_set_clientdata(i2c, chip);
 269
 270         return 0;
 271 }
 272
 273 static const struct i2c_device_id da9210_i2c_id[] = {
 274         {"da9210", 0},
 275         {},
 276 };
 277
 278 MODULE_DEVICE_TABLE(i2c, da9210_i2c_id);
 279
 280 static struct i2c_driver da9210_regulator_driver = {
 281         .driver = {
 282                 .name = "da9210",
 283                 .of_match_table = of_match_ptr(da9210_dt_ids),
 284         },
 285         .probe = da9210_i2c_probe,
 286         .id_table = da9210_i2c_id,
 287 };
 288
 289 module_i2c_driver(da9210_regulator_driver);
 290
 291 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
 292 MODULE_DESCRIPTION("Regulator device driver for Dialog DA9210");
 293 MODULE_LICENSE("GPL v2");