drivers/power/supply/mm8013.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2016-2019 The Linux Foundation. All rights reserved.
   4  * Copyright (c) 2023, Linaro Limited
   5  */
   6 #include <linux/delay.h>
   7 #include <linux/i2c.h>
   8 #include <linux/power_supply.h>
   9 #include <linux/regmap.h>
  10
  11 #define REG_BATID                       0x00 /* This one is very unclear */
  12  #define BATID_101                      0x0101 /* 107kOhm */
  13  #define BATID_102                      0x0102 /* 10kOhm */
  14 #define REG_TEMPERATURE                 0x06
  15 #define REG_VOLTAGE                     0x08
  16 #define REG_FLAGS                       0x0a
  17  #define MM8013_FLAG_OTC                BIT(15)
  18  #define MM8013_FLAG_OTD                BIT(14)
  19  #define MM8013_FLAG_BATHI              BIT(13)
  20  #define MM8013_FLAG_BATLOW             BIT(12)
  21  #define MM8013_FLAG_CHG_INH            BIT(11)
  22  #define MM8013_FLAG_FC                 BIT(9)
  23  #define MM8013_FLAG_CHG                BIT(8)
  24  #define MM8013_FLAG_OCC                BIT(6)
  25  #define MM8013_FLAG_ODC                BIT(5)
  26  #define MM8013_FLAG_OT                 BIT(4)
  27  #define MM8013_FLAG_UT                 BIT(3)
  28  #define MM8013_FLAG_DSG                BIT(0)
  29 #define REG_FULL_CHARGE_CAPACITY        0x0e
  30 #define REG_NOMINAL_CHARGE_CAPACITY     0x0c
  31 #define REG_AVERAGE_CURRENT             0x14
  32 #define REG_AVERAGE_TIME_TO_EMPTY       0x16
  33 #define REG_AVERAGE_TIME_TO_FULL        0x18
  34 #define REG_MAX_LOAD_CURRENT            0x1e
  35 #define REG_CYCLE_COUNT                 0x2a
  36 #define REG_STATE_OF_CHARGE             0x2c
  37 #define REG_DESIGN_CAPACITY             0x3c
  38 /* TODO: 0x62-0x68 seem to contain 'MM8013C' in a length-prefixed, non-terminated string */
  39
  40 #define DECIKELVIN_TO_DECIDEGC(t)       (t - 2731)
  41
  42 struct mm8013_chip {
  43         struct i2c_client *client;
  44         struct regmap *regmap;
  45 };
  46
  47 static int mm8013_checkdevice(struct mm8013_chip *chip)
  48 {
  49         int battery_id, ret;
  50         u32 val;
  51
  52         ret = regmap_write(chip->regmap, REG_BATID, 0x0008);
  53         if (ret < 0)
  54                 return ret;
  55
  56         ret = regmap_read(chip->regmap, REG_BATID, &val);
  57         if (ret < 0)
  58                 return ret;
  59
  60         if (val == BATID_102)
  61                 battery_id = 2;
  62         else if (val == BATID_101)
  63                 battery_id = 1;
  64         else
  65                 return -EINVAL;
  66
  67         dev_dbg(&chip->client->dev, "battery_id: %d\n", battery_id);
  68
  69         return 0;
  70 }
  71
  72 static enum power_supply_property mm8013_battery_props[] = {
  73         POWER_SUPPLY_PROP_CAPACITY,
  74         POWER_SUPPLY_PROP_CHARGE_FULL,
  75         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
  76         POWER_SUPPLY_PROP_CHARGE_NOW,
  77         POWER_SUPPLY_PROP_CURRENT_MAX,
  78         POWER_SUPPLY_PROP_CURRENT_NOW,
  79         POWER_SUPPLY_PROP_CYCLE_COUNT,
  80         POWER_SUPPLY_PROP_HEALTH,
  81         POWER_SUPPLY_PROP_PRESENT,
  82         POWER_SUPPLY_PROP_STATUS,
  83         POWER_SUPPLY_PROP_TEMP,
  84         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
  85         POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
  86         POWER_SUPPLY_PROP_VOLTAGE_NOW,
  87 };
  88
  89 static int mm8013_get_property(struct power_supply *psy,
  90                                enum power_supply_property psp,
  91                                union power_supply_propval *val)
  92 {
  93         struct mm8013_chip *chip = psy->drv_data;
  94         int ret = 0;
  95         u32 regval;
  96
  97         switch (psp) {
  98         case POWER_SUPPLY_PROP_CAPACITY:
  99                 ret = regmap_read(chip->regmap, REG_STATE_OF_CHARGE, &regval);
 100                 if (ret < 0)
 101                         return ret;
 102
 103                 val->intval = regval;
 104                 break;
 105         case POWER_SUPPLY_PROP_CHARGE_FULL:
 106                 ret = regmap_read(chip->regmap, REG_FULL_CHARGE_CAPACITY, &regval);
 107                 if (ret < 0)
 108                         return ret;
 109
 110                 val->intval = 1000 * regval;
 111                 break;
 112         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 113                 ret = regmap_read(chip->regmap, REG_DESIGN_CAPACITY, &regval);
 114                 if (ret < 0)
 115                         return ret;
 116
 117                 val->intval = 1000 * regval;
 118                 break;
 119         case POWER_SUPPLY_PROP_CHARGE_NOW:
 120                 ret = regmap_read(chip->regmap, REG_NOMINAL_CHARGE_CAPACITY, &regval);
 121                 if (ret < 0)
 122                         return ret;
 123
 124                 val->intval = 1000 * regval;
 125                 break;
 126         case POWER_SUPPLY_PROP_CURRENT_MAX:
 127                 ret = regmap_read(chip->regmap, REG_MAX_LOAD_CURRENT, &regval);
 128                 if (ret < 0)
 129                         return ret;
 130
 131                 val->intval = -1000 * (s16)regval;
 132                 break;
 133         case POWER_SUPPLY_PROP_CURRENT_NOW:
 134                 ret = regmap_read(chip->regmap, REG_AVERAGE_CURRENT, &regval);
 135                 if (ret < 0)
 136                         return ret;
 137
 138                 val->intval = -1000 * (s16)regval;
 139                 break;
 140         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 141                 ret = regmap_read(chip->regmap, REG_CYCLE_COUNT, &regval);
 142                 if (ret < 0)
 143                         return ret;
 144
 145                 val->intval = regval;
 146                 break;
 147         case POWER_SUPPLY_PROP_HEALTH:
 148                 ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
 149                 if (ret < 0)
 150                         return ret;
 151
 152                 if (regval & MM8013_FLAG_UT)
 153                         val->intval = POWER_SUPPLY_HEALTH_COLD;
 154                 else if (regval & (MM8013_FLAG_ODC | MM8013_FLAG_OCC))
 155                         val->intval = POWER_SUPPLY_HEALTH_OVERCURRENT;
 156                 else if (regval & (MM8013_FLAG_BATLOW))
 157                         val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
 158                 else if (regval & MM8013_FLAG_BATHI)
 159                         val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 160                 else if (regval & (MM8013_FLAG_OT | MM8013_FLAG_OTD | MM8013_FLAG_OTC))
 161                         val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
 162                 else
 163                         val->intval = POWER_SUPPLY_HEALTH_GOOD;
 164                 break;
 165         case POWER_SUPPLY_PROP_PRESENT:
 166                 ret = regmap_read(chip->regmap, REG_TEMPERATURE, &regval);
 167                 if (ret < 0)
 168                         return ret;
 169
 170                 val->intval = ((s16)regval > 0);
 171                 break;
 172         case POWER_SUPPLY_PROP_STATUS:
 173                 ret = regmap_read(chip->regmap, REG_FLAGS, &regval);
 174                 if (ret < 0)
 175                         return ret;
 176
 177                 if (regval & MM8013_FLAG_DSG)
 178                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 179                 else if (regval & MM8013_FLAG_CHG_INH)
 180                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 181                 else if (regval & MM8013_FLAG_CHG)
 182                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 183                 else if (regval & MM8013_FLAG_FC)
 184                         val->intval = POWER_SUPPLY_STATUS_FULL;
 185                 else
 186                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 187                 break;
 188         case POWER_SUPPLY_PROP_TEMP:
 189                 ret = regmap_read(chip->regmap, REG_TEMPERATURE, &regval);
 190                 if (ret < 0)
 191                         return ret;
 192
 193                 val->intval = DECIKELVIN_TO_DECIDEGC(regval);
 194                 break;
 195         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 196                 ret = regmap_read(chip->regmap, REG_AVERAGE_TIME_TO_EMPTY, &regval);
 197                 if (ret < 0)
 198                         return ret;
 199
 200                 /* The estimation is not yet ready */
 201                 if (regval == U16_MAX)
 202                         return -ENODATA;
 203
 204                 val->intval = regval;
 205                 break;
 206         case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
 207                 ret = regmap_read(chip->regmap, REG_AVERAGE_TIME_TO_FULL, &regval);
 208                 if (ret < 0)
 209                         return ret;
 210
 211                 /* The estimation is not yet ready */
 212                 if (regval == U16_MAX)
 213                         return -ENODATA;
 214
 215                 val->intval = regval;
 216                 break;
 217         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 218                 ret = regmap_read(chip->regmap, REG_VOLTAGE, &regval);
 219                 if (ret < 0)
 220                         return ret;
 221
 222                 val->intval = 1000 * regval;
 223                 break;
 224         default:
 225                 return -EINVAL;
 226         }
 227
 228         return 0;
 229 }
 230
 231 static const struct power_supply_desc mm8013_desc = {
 232         .name                   = "mm8013",
 233         .type                   = POWER_SUPPLY_TYPE_BATTERY,
 234         .properties             = mm8013_battery_props,
 235         .num_properties         = ARRAY_SIZE(mm8013_battery_props),
 236         .get_property           = mm8013_get_property,
 237 };
 238
 239 static const struct regmap_config mm8013_regmap_config = {
 240         .reg_bits = 8,
 241         .val_bits = 16,
 242         .max_register = 0x68,
 243         .use_single_read = true,
 244         .use_single_write = true,
 245         .val_format_endian = REGMAP_ENDIAN_LITTLE,
 246 };
 247
 248 static int mm8013_probe(struct i2c_client *client)
 249 {
 250         struct power_supply_config psy_cfg = {};
 251         struct device *dev = &client->dev;
 252         struct power_supply *psy;
 253         struct mm8013_chip *chip;
 254         int ret = 0;
 255
 256         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
 257                 return dev_err_probe(dev, -EIO,
 258                                      "I2C_FUNC_SMBUS_WORD_DATA not supported\n");
 259
 260         chip = devm_kzalloc(dev, sizeof(struct mm8013_chip), GFP_KERNEL);
 261         if (!chip)
 262                 return -ENOMEM;
 263
 264         chip->client = client;
 265
 266         chip->regmap = devm_regmap_init_i2c(client, &mm8013_regmap_config);
 267         if (IS_ERR(chip->regmap)) {
 268                 ret = PTR_ERR(chip->regmap);
 269                 return dev_err_probe(dev, ret, "Couldn't initialize regmap\n");
 270         }
 271
 272         ret = mm8013_checkdevice(chip);
 273         if (ret)
 274                 return dev_err_probe(dev, ret, "MM8013 not found\n");
 275
 276         psy_cfg.drv_data = chip;
 277         psy_cfg.of_node = dev->of_node;
 278
 279         psy = devm_power_supply_register(dev, &mm8013_desc, &psy_cfg);
 280         if (IS_ERR(psy))
 281                 return PTR_ERR(psy);
 282
 283         return 0;
 284 }
 285
 286 static const struct i2c_device_id mm8013_id_table[] = {
 287         { "mm8013", 0 },
 288         {}
 289 };
 290 MODULE_DEVICE_TABLE(i2c, mm8013_id_table);
 291
 292 static const struct of_device_id mm8013_match_table[] = {
 293         { .compatible = "mitsumi,mm8013" },
 294         {}
 295 };
 296
 297 static struct i2c_driver mm8013_i2c_driver = {
 298         .probe = mm8013_probe,
 299         .id_table = mm8013_id_table,
 300         .driver = {
 301                 .name = "mm8013",
 302                 .of_match_table = mm8013_match_table,
 303         },
 304 };
 305 module_i2c_driver(mm8013_i2c_driver);
 306
 307 MODULE_DESCRIPTION("MM8013 fuel gauge driver");
 308 MODULE_LICENSE("GPL");