drivers/power/supply/max77693_charger.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // max77693_charger.c - Battery charger driver for the Maxim 77693
   4 //
   5 // Copyright (C) 2014 Samsung Electronics
   6 // Krzysztof Kozlowski <krzk@kernel.org>
   7
   8 #include <linux/module.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/power_supply.h>
  11 #include <linux/regmap.h>
  12 #include <linux/mfd/max77693.h>
  13 #include <linux/mfd/max77693-common.h>
  14 #include <linux/mfd/max77693-private.h>
  15
  16 #define MAX77693_CHARGER_NAME                           "max77693-charger"
  17 static const char *max77693_charger_model               = "MAX77693";
  18 static const char *max77693_charger_manufacturer        = "Maxim Integrated";
  19
  20 struct max77693_charger {
  21         struct device           *dev;
  22         struct max77693_dev     *max77693;
  23         struct power_supply     *charger;
  24
  25         u32 constant_volt;
  26         u32 min_system_volt;
  27         u32 thermal_regulation_temp;
  28         u32 batttery_overcurrent;
  29         u32 charge_input_threshold_volt;
  30 };
  31
  32 static int max77693_get_charger_state(struct regmap *regmap, int *val)
  33 {
  34         int ret;
  35         unsigned int data;
  36
  37         ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
  38         if (ret < 0)
  39                 return ret;
  40
  41         data &= CHG_DETAILS_01_CHG_MASK;
  42         data >>= CHG_DETAILS_01_CHG_SHIFT;
  43
  44         switch (data) {
  45         case MAX77693_CHARGING_PREQUALIFICATION:
  46         case MAX77693_CHARGING_FAST_CONST_CURRENT:
  47         case MAX77693_CHARGING_FAST_CONST_VOLTAGE:
  48         case MAX77693_CHARGING_TOP_OFF:
  49         /* In high temp the charging current is reduced, but still charging */
  50         case MAX77693_CHARGING_HIGH_TEMP:
  51                 *val = POWER_SUPPLY_STATUS_CHARGING;
  52                 break;
  53         case MAX77693_CHARGING_DONE:
  54                 *val = POWER_SUPPLY_STATUS_FULL;
  55                 break;
  56         case MAX77693_CHARGING_TIMER_EXPIRED:
  57         case MAX77693_CHARGING_THERMISTOR_SUSPEND:
  58                 *val = POWER_SUPPLY_STATUS_NOT_CHARGING;
  59                 break;
  60         case MAX77693_CHARGING_OFF:
  61         case MAX77693_CHARGING_OVER_TEMP:
  62         case MAX77693_CHARGING_WATCHDOG_EXPIRED:
  63                 *val = POWER_SUPPLY_STATUS_DISCHARGING;
  64                 break;
  65         case MAX77693_CHARGING_RESERVED:
  66         default:
  67                 *val = POWER_SUPPLY_STATUS_UNKNOWN;
  68         }
  69
  70         return 0;
  71 }
  72
  73 static int max77693_get_charge_type(struct regmap *regmap, int *val)
  74 {
  75         int ret;
  76         unsigned int data;
  77
  78         ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
  79         if (ret < 0)
  80                 return ret;
  81
  82         data &= CHG_DETAILS_01_CHG_MASK;
  83         data >>= CHG_DETAILS_01_CHG_SHIFT;
  84
  85         switch (data) {
  86         case MAX77693_CHARGING_PREQUALIFICATION:
  87         /*
  88          * Top-off: trickle or fast? In top-off the current varies between
  89          * 100 and 250 mA. It is higher than prequalification current.
  90          */
  91         case MAX77693_CHARGING_TOP_OFF:
  92                 *val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
  93                 break;
  94         case MAX77693_CHARGING_FAST_CONST_CURRENT:
  95         case MAX77693_CHARGING_FAST_CONST_VOLTAGE:
  96         /* In high temp the charging current is reduced, but still charging */
  97         case MAX77693_CHARGING_HIGH_TEMP:
  98                 *val = POWER_SUPPLY_CHARGE_TYPE_FAST;
  99                 break;
 100         case MAX77693_CHARGING_DONE:
 101         case MAX77693_CHARGING_TIMER_EXPIRED:
 102         case MAX77693_CHARGING_THERMISTOR_SUSPEND:
 103         case MAX77693_CHARGING_OFF:
 104         case MAX77693_CHARGING_OVER_TEMP:
 105         case MAX77693_CHARGING_WATCHDOG_EXPIRED:
 106                 *val = POWER_SUPPLY_CHARGE_TYPE_NONE;
 107                 break;
 108         case MAX77693_CHARGING_RESERVED:
 109         default:
 110                 *val = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
 111         }
 112
 113         return 0;
 114 }
 115
 116 /*
 117  * Supported health statuses:
 118  *  - POWER_SUPPLY_HEALTH_DEAD
 119  *  - POWER_SUPPLY_HEALTH_GOOD
 120  *  - POWER_SUPPLY_HEALTH_OVERVOLTAGE
 121  *  - POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE
 122  *  - POWER_SUPPLY_HEALTH_UNKNOWN
 123  *  - POWER_SUPPLY_HEALTH_UNSPEC_FAILURE
 124  */
 125 static int max77693_get_battery_health(struct regmap *regmap, int *val)
 126 {
 127         int ret;
 128         unsigned int data;
 129
 130         ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
 131         if (ret < 0)
 132                 return ret;
 133
 134         data &= CHG_DETAILS_01_BAT_MASK;
 135         data >>= CHG_DETAILS_01_BAT_SHIFT;
 136
 137         switch (data) {
 138         case MAX77693_BATTERY_NOBAT:
 139                 *val = POWER_SUPPLY_HEALTH_DEAD;
 140                 break;
 141         case MAX77693_BATTERY_PREQUALIFICATION:
 142         case MAX77693_BATTERY_GOOD:
 143         case MAX77693_BATTERY_LOWVOLTAGE:
 144                 *val = POWER_SUPPLY_HEALTH_GOOD;
 145                 break;
 146         case MAX77693_BATTERY_TIMER_EXPIRED:
 147                 /*
 148                  * Took longer to charge than expected, charging suspended.
 149                  * Damaged battery?
 150                  */
 151                 *val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
 152                 break;
 153         case MAX77693_BATTERY_OVERVOLTAGE:
 154                 *val = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 155                 break;
 156         case MAX77693_BATTERY_OVERCURRENT:
 157                 *val = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
 158                 break;
 159         case MAX77693_BATTERY_RESERVED:
 160         default:
 161                 *val = POWER_SUPPLY_HEALTH_UNKNOWN;
 162                 break;
 163         }
 164
 165         return 0;
 166 }
 167
 168 static int max77693_get_present(struct regmap *regmap, int *val)
 169 {
 170         unsigned int data;
 171         int ret;
 172
 173         /*
 174          * Read CHG_INT_OK register. High DETBAT bit here should be
 175          * equal to value 0x0 in CHG_DETAILS_01/BAT field.
 176          */
 177         ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data);
 178         if (ret < 0)
 179                 return ret;
 180
 181         *val = (data & CHG_INT_OK_DETBAT_MASK) ? 0 : 1;
 182
 183         return 0;
 184 }
 185
 186 static int max77693_get_online(struct regmap *regmap, int *val)
 187 {
 188         unsigned int data;
 189         int ret;
 190
 191         ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data);
 192         if (ret < 0)
 193                 return ret;
 194
 195         *val = (data & CHG_INT_OK_CHGIN_MASK) ? 1 : 0;
 196
 197         return 0;
 198 }
 199
 200 static enum power_supply_property max77693_charger_props[] = {
 201         POWER_SUPPLY_PROP_STATUS,
 202         POWER_SUPPLY_PROP_CHARGE_TYPE,
 203         POWER_SUPPLY_PROP_HEALTH,
 204         POWER_SUPPLY_PROP_PRESENT,
 205         POWER_SUPPLY_PROP_ONLINE,
 206         POWER_SUPPLY_PROP_MODEL_NAME,
 207         POWER_SUPPLY_PROP_MANUFACTURER,
 208 };
 209
 210 static int max77693_charger_get_property(struct power_supply *psy,
 211                             enum power_supply_property psp,
 212                             union power_supply_propval *val)
 213 {
 214         struct max77693_charger *chg = power_supply_get_drvdata(psy);
 215         struct regmap *regmap = chg->max77693->regmap;
 216         int ret = 0;
 217
 218         switch (psp) {
 219         case POWER_SUPPLY_PROP_STATUS:
 220                 ret = max77693_get_charger_state(regmap, &val->intval);
 221                 break;
 222         case POWER_SUPPLY_PROP_CHARGE_TYPE:
 223                 ret = max77693_get_charge_type(regmap, &val->intval);
 224                 break;
 225         case POWER_SUPPLY_PROP_HEALTH:
 226                 ret = max77693_get_battery_health(regmap, &val->intval);
 227                 break;
 228         case POWER_SUPPLY_PROP_PRESENT:
 229                 ret = max77693_get_present(regmap, &val->intval);
 230                 break;
 231         case POWER_SUPPLY_PROP_ONLINE:
 232                 ret = max77693_get_online(regmap, &val->intval);
 233                 break;
 234         case POWER_SUPPLY_PROP_MODEL_NAME:
 235                 val->strval = max77693_charger_model;
 236                 break;
 237         case POWER_SUPPLY_PROP_MANUFACTURER:
 238                 val->strval = max77693_charger_manufacturer;
 239                 break;
 240         default:
 241                 return -EINVAL;
 242         }
 243
 244         return ret;
 245 }
 246
 247 static const struct power_supply_desc max77693_charger_desc = {
 248         .name           = MAX77693_CHARGER_NAME,
 249         .type           = POWER_SUPPLY_TYPE_BATTERY,
 250         .properties     = max77693_charger_props,
 251         .num_properties = ARRAY_SIZE(max77693_charger_props),
 252         .get_property   = max77693_charger_get_property,
 253 };
 254
 255 static ssize_t device_attr_store(struct device *dev,
 256                 struct device_attribute *attr, const char *buf, size_t count,
 257                 int (*fn)(struct max77693_charger *, unsigned long))
 258 {
 259         struct max77693_charger *chg = dev_get_drvdata(dev);
 260         unsigned long val;
 261         int ret;
 262
 263         ret = kstrtoul(buf, 10, &val);
 264         if (ret)
 265                 return ret;
 266
 267         ret = fn(chg, val);
 268         if (ret)
 269                 return ret;
 270
 271         return count;
 272 }
 273
 274 static ssize_t fast_charge_timer_show(struct device *dev,
 275                 struct device_attribute *attr, char *buf)
 276 {
 277         struct max77693_charger *chg = dev_get_drvdata(dev);
 278         unsigned int data, val;
 279         int ret;
 280
 281         ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_01,
 282                         &data);
 283         if (ret < 0)
 284                 return ret;
 285
 286         data &= CHG_CNFG_01_FCHGTIME_MASK;
 287         data >>= CHG_CNFG_01_FCHGTIME_SHIFT;
 288         switch (data) {
 289         case 0x1 ... 0x7:
 290                 /* Starting from 4 hours, step by 2 hours */
 291                 val = 4 + (data - 1) * 2;
 292                 break;
 293         case 0x0:
 294         default:
 295                 val = 0;
 296                 break;
 297         }
 298
 299         return sysfs_emit(buf, "%u\n", val);
 300 }
 301
 302 static int max77693_set_fast_charge_timer(struct max77693_charger *chg,
 303                 unsigned long hours)
 304 {
 305         unsigned int data;
 306
 307         /*
 308          * 0x00 - disable
 309          * 0x01 - 4h
 310          * 0x02 - 6h
 311          * ...
 312          * 0x07 - 16h
 313          * Round down odd values.
 314          */
 315         switch (hours) {
 316         case 4 ... 16:
 317                 data = (hours - 4) / 2 + 1;
 318                 break;
 319         case 0:
 320                 /* Disable */
 321                 data = 0;
 322                 break;
 323         default:
 324                 return -EINVAL;
 325         }
 326         data <<= CHG_CNFG_01_FCHGTIME_SHIFT;
 327
 328         return regmap_update_bits(chg->max77693->regmap,
 329                         MAX77693_CHG_REG_CHG_CNFG_01,
 330                         CHG_CNFG_01_FCHGTIME_MASK, data);
 331 }
 332
 333 static ssize_t fast_charge_timer_store(struct device *dev,
 334                 struct device_attribute *attr, const char *buf, size_t count)
 335 {
 336         return device_attr_store(dev, attr, buf, count,
 337                         max77693_set_fast_charge_timer);
 338 }
 339
 340 static ssize_t top_off_threshold_current_show(struct device *dev,
 341                 struct device_attribute *attr, char *buf)
 342 {
 343         struct max77693_charger *chg = dev_get_drvdata(dev);
 344         unsigned int data, val;
 345         int ret;
 346
 347         ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03,
 348                         &data);
 349         if (ret < 0)
 350                 return ret;
 351
 352         data &= CHG_CNFG_03_TOITH_MASK;
 353         data >>= CHG_CNFG_03_TOITH_SHIFT;
 354
 355         if (data <= 0x04)
 356                 val = 100000 + data * 25000;
 357         else
 358                 val = data * 50000;
 359
 360         return sysfs_emit(buf, "%u\n", val);
 361 }
 362
 363 static int max77693_set_top_off_threshold_current(struct max77693_charger *chg,
 364                 unsigned long uamp)
 365 {
 366         unsigned int data;
 367
 368         if (uamp < 100000 || uamp > 350000)
 369                 return -EINVAL;
 370
 371         if (uamp <= 200000)
 372                 data = (uamp - 100000) / 25000;
 373         else
 374                 /* (200000, 350000> */
 375                 data = uamp / 50000;
 376
 377         data <<= CHG_CNFG_03_TOITH_SHIFT;
 378
 379         return regmap_update_bits(chg->max77693->regmap,
 380                         MAX77693_CHG_REG_CHG_CNFG_03,
 381                         CHG_CNFG_03_TOITH_MASK, data);
 382 }
 383
 384 static ssize_t top_off_threshold_current_store(struct device *dev,
 385                 struct device_attribute *attr, const char *buf, size_t count)
 386 {
 387         return device_attr_store(dev, attr, buf, count,
 388                         max77693_set_top_off_threshold_current);
 389 }
 390
 391 static ssize_t top_off_timer_show(struct device *dev,
 392                 struct device_attribute *attr, char *buf)
 393 {
 394         struct max77693_charger *chg = dev_get_drvdata(dev);
 395         unsigned int data, val;
 396         int ret;
 397
 398         ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03,
 399                         &data);
 400         if (ret < 0)
 401                 return ret;
 402
 403         data &= CHG_CNFG_03_TOTIME_MASK;
 404         data >>= CHG_CNFG_03_TOTIME_SHIFT;
 405
 406         val = data * 10;
 407
 408         return sysfs_emit(buf, "%u\n", val);
 409 }
 410
 411 static int max77693_set_top_off_timer(struct max77693_charger *chg,
 412                 unsigned long minutes)
 413 {
 414         unsigned int data;
 415
 416         if (minutes > 70)
 417                 return -EINVAL;
 418
 419         data = minutes / 10;
 420         data <<= CHG_CNFG_03_TOTIME_SHIFT;
 421
 422         return regmap_update_bits(chg->max77693->regmap,
 423                         MAX77693_CHG_REG_CHG_CNFG_03,
 424                         CHG_CNFG_03_TOTIME_MASK, data);
 425 }
 426
 427 static ssize_t top_off_timer_store(struct device *dev,
 428                 struct device_attribute *attr, const char *buf, size_t count)
 429 {
 430         return device_attr_store(dev, attr, buf, count,
 431                         max77693_set_top_off_timer);
 432 }
 433
 434 static DEVICE_ATTR_RW(fast_charge_timer);
 435 static DEVICE_ATTR_RW(top_off_threshold_current);
 436 static DEVICE_ATTR_RW(top_off_timer);
 437
 438 static int max77693_set_constant_volt(struct max77693_charger *chg,
 439                 unsigned int uvolt)
 440 {
 441         unsigned int data;
 442
 443         /*
 444          * 0x00 - 3.650 V
 445          * 0x01 - 3.675 V
 446          * ...
 447          * 0x1b - 4.325 V
 448          * 0x1c - 4.340 V
 449          * 0x1d - 4.350 V
 450          * 0x1e - 4.375 V
 451          * 0x1f - 4.400 V
 452          */
 453         if (uvolt >= 3650000 && uvolt < 4340000)
 454                 data = (uvolt - 3650000) / 25000;
 455         else if (uvolt >= 4340000 && uvolt < 4350000)
 456                 data = 0x1c;
 457         else if (uvolt >= 4350000 && uvolt <= 4400000)
 458                 data = 0x1d + (uvolt - 4350000) / 25000;
 459         else {
 460                 dev_err(chg->dev, "Wrong value for charging constant voltage\n");
 461                 return -EINVAL;
 462         }
 463
 464         data <<= CHG_CNFG_04_CHGCVPRM_SHIFT;
 465
 466         dev_dbg(chg->dev, "Charging constant voltage: %u (0x%x)\n", uvolt,
 467                         data);
 468
 469         return regmap_update_bits(chg->max77693->regmap,
 470                         MAX77693_CHG_REG_CHG_CNFG_04,
 471                         CHG_CNFG_04_CHGCVPRM_MASK, data);
 472 }
 473
 474 static int max77693_set_min_system_volt(struct max77693_charger *chg,
 475                 unsigned int uvolt)
 476 {
 477         unsigned int data;
 478
 479         if (uvolt < 3000000 || uvolt > 3700000) {
 480                 dev_err(chg->dev, "Wrong value for minimum system regulation voltage\n");
 481                 return -EINVAL;
 482         }
 483
 484         data = (uvolt - 3000000) / 100000;
 485
 486         data <<= CHG_CNFG_04_MINVSYS_SHIFT;
 487
 488         dev_dbg(chg->dev, "Minimum system regulation voltage: %u (0x%x)\n",
 489                         uvolt, data);
 490
 491         return regmap_update_bits(chg->max77693->regmap,
 492                         MAX77693_CHG_REG_CHG_CNFG_04,
 493                         CHG_CNFG_04_MINVSYS_MASK, data);
 494 }
 495
 496 static int max77693_set_thermal_regulation_temp(struct max77693_charger *chg,
 497                 unsigned int cels)
 498 {
 499         unsigned int data;
 500
 501         switch (cels) {
 502         case 70:
 503         case 85:
 504         case 100:
 505         case 115:
 506                 data = (cels - 70) / 15;
 507                 break;
 508         default:
 509                 dev_err(chg->dev, "Wrong value for thermal regulation loop temperature\n");
 510                 return -EINVAL;
 511         }
 512
 513         data <<= CHG_CNFG_07_REGTEMP_SHIFT;
 514
 515         dev_dbg(chg->dev, "Thermal regulation loop temperature: %u (0x%x)\n",
 516                         cels, data);
 517
 518         return regmap_update_bits(chg->max77693->regmap,
 519                         MAX77693_CHG_REG_CHG_CNFG_07,
 520                         CHG_CNFG_07_REGTEMP_MASK, data);
 521 }
 522
 523 static int max77693_set_batttery_overcurrent(struct max77693_charger *chg,
 524                 unsigned int uamp)
 525 {
 526         unsigned int data;
 527
 528         if (uamp && (uamp < 2000000 || uamp > 3500000)) {
 529                 dev_err(chg->dev, "Wrong value for battery overcurrent\n");
 530                 return -EINVAL;
 531         }
 532
 533         if (uamp)
 534                 data = ((uamp - 2000000) / 250000) + 1;
 535         else
 536                 data = 0; /* disable */
 537
 538         data <<= CHG_CNFG_12_B2SOVRC_SHIFT;
 539
 540         dev_dbg(chg->dev, "Battery overcurrent: %u (0x%x)\n", uamp, data);
 541
 542         return regmap_update_bits(chg->max77693->regmap,
 543                         MAX77693_CHG_REG_CHG_CNFG_12,
 544                         CHG_CNFG_12_B2SOVRC_MASK, data);
 545 }
 546
 547 static int max77693_set_charge_input_threshold_volt(struct max77693_charger *chg,
 548                 unsigned int uvolt)
 549 {
 550         unsigned int data;
 551
 552         switch (uvolt) {
 553         case 4300000:
 554                 data = 0x0;
 555                 break;
 556         case 4700000:
 557         case 4800000:
 558         case 4900000:
 559                 data = (uvolt - 4700000) / 100000;
 560                 break;
 561         default:
 562                 dev_err(chg->dev, "Wrong value for charge input voltage regulation threshold\n");
 563                 return -EINVAL;
 564         }
 565
 566         data <<= CHG_CNFG_12_VCHGINREG_SHIFT;
 567
 568         dev_dbg(chg->dev, "Charge input voltage regulation threshold: %u (0x%x)\n",
 569                         uvolt, data);
 570
 571         return regmap_update_bits(chg->max77693->regmap,
 572                         MAX77693_CHG_REG_CHG_CNFG_12,
 573                         CHG_CNFG_12_VCHGINREG_MASK, data);
 574 }
 575
 576 /*
 577  * Sets charger registers to proper and safe default values.
 578  */
 579 static int max77693_reg_init(struct max77693_charger *chg)
 580 {
 581         int ret;
 582         unsigned int data;
 583
 584         /* Unlock charger register protection */
 585         data = (0x3 << CHG_CNFG_06_CHGPROT_SHIFT);
 586         ret = regmap_update_bits(chg->max77693->regmap,
 587                                 MAX77693_CHG_REG_CHG_CNFG_06,
 588                                 CHG_CNFG_06_CHGPROT_MASK, data);
 589         if (ret) {
 590                 dev_err(chg->dev, "Error unlocking registers: %d\n", ret);
 591                 return ret;
 592         }
 593
 594         ret = max77693_set_fast_charge_timer(chg, DEFAULT_FAST_CHARGE_TIMER);
 595         if (ret)
 596                 return ret;
 597
 598         ret = max77693_set_top_off_threshold_current(chg,
 599                         DEFAULT_TOP_OFF_THRESHOLD_CURRENT);
 600         if (ret)
 601                 return ret;
 602
 603         ret = max77693_set_top_off_timer(chg, DEFAULT_TOP_OFF_TIMER);
 604         if (ret)
 605                 return ret;
 606
 607         ret = max77693_set_constant_volt(chg, chg->constant_volt);
 608         if (ret)
 609                 return ret;
 610
 611         ret = max77693_set_min_system_volt(chg, chg->min_system_volt);
 612         if (ret)
 613                 return ret;
 614
 615         ret = max77693_set_thermal_regulation_temp(chg,
 616                         chg->thermal_regulation_temp);
 617         if (ret)
 618                 return ret;
 619
 620         ret = max77693_set_batttery_overcurrent(chg, chg->batttery_overcurrent);
 621         if (ret)
 622                 return ret;
 623
 624         return max77693_set_charge_input_threshold_volt(chg,
 625                         chg->charge_input_threshold_volt);
 626 }
 627
 628 #ifdef CONFIG_OF
 629 static int max77693_dt_init(struct device *dev, struct max77693_charger *chg)
 630 {
 631         struct device_node *np = dev->of_node;
 632
 633         if (!np) {
 634                 dev_err(dev, "no charger OF node\n");
 635                 return -EINVAL;
 636         }
 637
 638         if (of_property_read_u32(np, "maxim,constant-microvolt",
 639                         &chg->constant_volt))
 640                 chg->constant_volt = DEFAULT_CONSTANT_VOLT;
 641
 642         if (of_property_read_u32(np, "maxim,min-system-microvolt",
 643                         &chg->min_system_volt))
 644                 chg->min_system_volt = DEFAULT_MIN_SYSTEM_VOLT;
 645
 646         if (of_property_read_u32(np, "maxim,thermal-regulation-celsius",
 647                         &chg->thermal_regulation_temp))
 648                 chg->thermal_regulation_temp = DEFAULT_THERMAL_REGULATION_TEMP;
 649
 650         if (of_property_read_u32(np, "maxim,battery-overcurrent-microamp",
 651                         &chg->batttery_overcurrent))
 652                 chg->batttery_overcurrent = DEFAULT_BATTERY_OVERCURRENT;
 653
 654         if (of_property_read_u32(np, "maxim,charge-input-threshold-microvolt",
 655                         &chg->charge_input_threshold_volt))
 656                 chg->charge_input_threshold_volt =
 657                         DEFAULT_CHARGER_INPUT_THRESHOLD_VOLT;
 658
 659         return 0;
 660 }
 661 #else /* CONFIG_OF */
 662 static int max77693_dt_init(struct device *dev, struct max77693_charger *chg)
 663 {
 664         return 0;
 665 }
 666 #endif /* CONFIG_OF */
 667
 668 static int max77693_charger_probe(struct platform_device *pdev)
 669 {
 670         struct max77693_charger *chg;
 671         struct power_supply_config psy_cfg = {};
 672         struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
 673         int ret;
 674
 675         chg = devm_kzalloc(&pdev->dev, sizeof(*chg), GFP_KERNEL);
 676         if (!chg)
 677                 return -ENOMEM;
 678
 679         platform_set_drvdata(pdev, chg);
 680         chg->dev = &pdev->dev;
 681         chg->max77693 = max77693;
 682
 683         ret = max77693_dt_init(&pdev->dev, chg);
 684         if (ret)
 685                 return ret;
 686
 687         ret = max77693_reg_init(chg);
 688         if (ret)
 689                 return ret;
 690
 691         psy_cfg.drv_data = chg;
 692
 693         ret = device_create_file(&pdev->dev, &dev_attr_fast_charge_timer);
 694         if (ret) {
 695                 dev_err(&pdev->dev, "failed: create fast charge timer sysfs entry\n");
 696                 goto err;
 697         }
 698
 699         ret = device_create_file(&pdev->dev,
 700                         &dev_attr_top_off_threshold_current);
 701         if (ret) {
 702                 dev_err(&pdev->dev, "failed: create top off current sysfs entry\n");
 703                 goto err;
 704         }
 705
 706         ret = device_create_file(&pdev->dev, &dev_attr_top_off_timer);
 707         if (ret) {
 708                 dev_err(&pdev->dev, "failed: create top off timer sysfs entry\n");
 709                 goto err;
 710         }
 711
 712         chg->charger = power_supply_register(&pdev->dev,
 713                                                 &max77693_charger_desc,
 714                                                 &psy_cfg);
 715         if (IS_ERR(chg->charger)) {
 716                 dev_err(&pdev->dev, "failed: power supply register\n");
 717                 ret = PTR_ERR(chg->charger);
 718                 goto err;
 719         }
 720
 721         return 0;
 722
 723 err:
 724         device_remove_file(&pdev->dev, &dev_attr_top_off_timer);
 725         device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current);
 726         device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
 727
 728         return ret;
 729 }
 730
 731 static void max77693_charger_remove(struct platform_device *pdev)
 732 {
 733         struct max77693_charger *chg = platform_get_drvdata(pdev);
 734
 735         device_remove_file(&pdev->dev, &dev_attr_top_off_timer);
 736         device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current);
 737         device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
 738
 739         power_supply_unregister(chg->charger);
 740 }
 741
 742 static const struct platform_device_id max77693_charger_id[] = {
 743         { "max77693-charger", 0, },
 744         { }
 745 };
 746 MODULE_DEVICE_TABLE(platform, max77693_charger_id);
 747
 748 static struct platform_driver max77693_charger_driver = {
 749         .driver = {
 750                 .name   = "max77693-charger",
 751         },
 752         .probe          = max77693_charger_probe,
 753         .remove_new     = max77693_charger_remove,
 754         .id_table       = max77693_charger_id,
 755 };
 756 module_platform_driver(max77693_charger_driver);
 757
 758 MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
 759 MODULE_DESCRIPTION("Maxim 77693 charger driver");
 760 MODULE_LICENSE("GPL");