linux/drivers/regulator/da9210-regulator.c
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   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
  34struct da9210 {
  35        struct regulator_dev *rdev;
  36        struct regmap *regmap;
  37};
  38
  39static const struct regmap_config da9210_regmap_config = {
  40        .reg_bits = 8,
  41        .val_bits = 8,
  42};
  43
  44static int da9210_set_current_limit(struct regulator_dev *rdev, int min_uA,
  45                                    int max_uA);
  46static int da9210_get_current_limit(struct regulator_dev *rdev);
  47
  48static 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 */
  65static 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
  70static 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
  85static 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
 107static 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
 124static 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
 173error_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
 182static const struct of_device_id da9210_dt_ids[] = {
 183        { .compatible = "dlg,da9210", },
 184        { }
 185};
 186MODULE_DEVICE_TABLE(of, da9210_dt_ids);
 187
 188static 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
 273static const struct i2c_device_id da9210_i2c_id[] = {
 274        {"da9210", 0},
 275        {},
 276};
 277
 278MODULE_DEVICE_TABLE(i2c, da9210_i2c_id);
 279
 280static 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
 289module_i2c_driver(da9210_regulator_driver);
 290
 291MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
 292MODULE_DESCRIPTION("Regulator device driver for Dialog DA9210");
 293MODULE_LICENSE("GPL v2");
 294