linux/drivers/power/supply/max77693_charger.c
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   1/*
   2 * max77693_charger.c - Battery charger driver for the Maxim 77693
   3 *
   4 * Copyright (C) 2014 Samsung Electronics
   5 * Krzysztof Kozlowski <krzk@kernel.org>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 */
  17
  18#include <linux/module.h>
  19#include <linux/platform_device.h>
  20#include <linux/power_supply.h>
  21#include <linux/regmap.h>
  22#include <linux/mfd/max77693.h>
  23#include <linux/mfd/max77693-common.h>
  24#include <linux/mfd/max77693-private.h>
  25
  26#define MAX77693_CHARGER_NAME                           "max77693-charger"
  27static const char *max77693_charger_model               = "MAX77693";
  28static const char *max77693_charger_manufacturer        = "Maxim Integrated";
  29
  30struct max77693_charger {
  31        struct device           *dev;
  32        struct max77693_dev     *max77693;
  33        struct power_supply     *charger;
  34
  35        u32 constant_volt;
  36        u32 min_system_volt;
  37        u32 thermal_regulation_temp;
  38        u32 batttery_overcurrent;
  39        u32 charge_input_threshold_volt;
  40};
  41
  42static int max77693_get_charger_state(struct regmap *regmap, int *val)
  43{
  44        int ret;
  45        unsigned int data;
  46
  47        ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
  48        if (ret < 0)
  49                return ret;
  50
  51        data &= CHG_DETAILS_01_CHG_MASK;
  52        data >>= CHG_DETAILS_01_CHG_SHIFT;
  53
  54        switch (data) {
  55        case MAX77693_CHARGING_PREQUALIFICATION:
  56        case MAX77693_CHARGING_FAST_CONST_CURRENT:
  57        case MAX77693_CHARGING_FAST_CONST_VOLTAGE:
  58        case MAX77693_CHARGING_TOP_OFF:
  59        /* In high temp the charging current is reduced, but still charging */
  60        case MAX77693_CHARGING_HIGH_TEMP:
  61                *val = POWER_SUPPLY_STATUS_CHARGING;
  62                break;
  63        case MAX77693_CHARGING_DONE:
  64                *val = POWER_SUPPLY_STATUS_FULL;
  65                break;
  66        case MAX77693_CHARGING_TIMER_EXPIRED:
  67        case MAX77693_CHARGING_THERMISTOR_SUSPEND:
  68                *val = POWER_SUPPLY_STATUS_NOT_CHARGING;
  69                break;
  70        case MAX77693_CHARGING_OFF:
  71        case MAX77693_CHARGING_OVER_TEMP:
  72        case MAX77693_CHARGING_WATCHDOG_EXPIRED:
  73                *val = POWER_SUPPLY_STATUS_DISCHARGING;
  74                break;
  75        case MAX77693_CHARGING_RESERVED:
  76        default:
  77                *val = POWER_SUPPLY_STATUS_UNKNOWN;
  78        }
  79
  80        return 0;
  81}
  82
  83static int max77693_get_charge_type(struct regmap *regmap, int *val)
  84{
  85        int ret;
  86        unsigned int data;
  87
  88        ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
  89        if (ret < 0)
  90                return ret;
  91
  92        data &= CHG_DETAILS_01_CHG_MASK;
  93        data >>= CHG_DETAILS_01_CHG_SHIFT;
  94
  95        switch (data) {
  96        case MAX77693_CHARGING_PREQUALIFICATION:
  97        /*
  98         * Top-off: trickle or fast? In top-off the current varies between
  99         * 100 and 250 mA. It is higher than prequalification current.
 100         */
 101        case MAX77693_CHARGING_TOP_OFF:
 102                *val = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
 103                break;
 104        case MAX77693_CHARGING_FAST_CONST_CURRENT:
 105        case MAX77693_CHARGING_FAST_CONST_VOLTAGE:
 106        /* In high temp the charging current is reduced, but still charging */
 107        case MAX77693_CHARGING_HIGH_TEMP:
 108                *val = POWER_SUPPLY_CHARGE_TYPE_FAST;
 109                break;
 110        case MAX77693_CHARGING_DONE:
 111        case MAX77693_CHARGING_TIMER_EXPIRED:
 112        case MAX77693_CHARGING_THERMISTOR_SUSPEND:
 113        case MAX77693_CHARGING_OFF:
 114        case MAX77693_CHARGING_OVER_TEMP:
 115        case MAX77693_CHARGING_WATCHDOG_EXPIRED:
 116                *val = POWER_SUPPLY_CHARGE_TYPE_NONE;
 117                break;
 118        case MAX77693_CHARGING_RESERVED:
 119        default:
 120                *val = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
 121        }
 122
 123        return 0;
 124}
 125
 126/*
 127 * Supported health statuses:
 128 *  - POWER_SUPPLY_HEALTH_DEAD
 129 *  - POWER_SUPPLY_HEALTH_GOOD
 130 *  - POWER_SUPPLY_HEALTH_OVERVOLTAGE
 131 *  - POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE
 132 *  - POWER_SUPPLY_HEALTH_UNKNOWN
 133 *  - POWER_SUPPLY_HEALTH_UNSPEC_FAILURE
 134 */
 135static int max77693_get_battery_health(struct regmap *regmap, int *val)
 136{
 137        int ret;
 138        unsigned int data;
 139
 140        ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_DETAILS_01, &data);
 141        if (ret < 0)
 142                return ret;
 143
 144        data &= CHG_DETAILS_01_BAT_MASK;
 145        data >>= CHG_DETAILS_01_BAT_SHIFT;
 146
 147        switch (data) {
 148        case MAX77693_BATTERY_NOBAT:
 149                *val = POWER_SUPPLY_HEALTH_DEAD;
 150                break;
 151        case MAX77693_BATTERY_PREQUALIFICATION:
 152        case MAX77693_BATTERY_GOOD:
 153        case MAX77693_BATTERY_LOWVOLTAGE:
 154                *val = POWER_SUPPLY_HEALTH_GOOD;
 155                break;
 156        case MAX77693_BATTERY_TIMER_EXPIRED:
 157                /*
 158                 * Took longer to charge than expected, charging suspended.
 159                 * Damaged battery?
 160                 */
 161                *val = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
 162                break;
 163        case MAX77693_BATTERY_OVERVOLTAGE:
 164                *val = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 165                break;
 166        case MAX77693_BATTERY_OVERCURRENT:
 167                *val = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
 168                break;
 169        case MAX77693_BATTERY_RESERVED:
 170        default:
 171                *val = POWER_SUPPLY_HEALTH_UNKNOWN;
 172                break;
 173        }
 174
 175        return 0;
 176}
 177
 178static int max77693_get_present(struct regmap *regmap, int *val)
 179{
 180        unsigned int data;
 181        int ret;
 182
 183        /*
 184         * Read CHG_INT_OK register. High DETBAT bit here should be
 185         * equal to value 0x0 in CHG_DETAILS_01/BAT field.
 186         */
 187        ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data);
 188        if (ret < 0)
 189                return ret;
 190
 191        *val = (data & CHG_INT_OK_DETBAT_MASK) ? 0 : 1;
 192
 193        return 0;
 194}
 195
 196static int max77693_get_online(struct regmap *regmap, int *val)
 197{
 198        unsigned int data;
 199        int ret;
 200
 201        ret = regmap_read(regmap, MAX77693_CHG_REG_CHG_INT_OK, &data);
 202        if (ret < 0)
 203                return ret;
 204
 205        *val = (data & CHG_INT_OK_CHGIN_MASK) ? 1 : 0;
 206
 207        return 0;
 208}
 209
 210static enum power_supply_property max77693_charger_props[] = {
 211        POWER_SUPPLY_PROP_STATUS,
 212        POWER_SUPPLY_PROP_CHARGE_TYPE,
 213        POWER_SUPPLY_PROP_HEALTH,
 214        POWER_SUPPLY_PROP_PRESENT,
 215        POWER_SUPPLY_PROP_ONLINE,
 216        POWER_SUPPLY_PROP_MODEL_NAME,
 217        POWER_SUPPLY_PROP_MANUFACTURER,
 218};
 219
 220static int max77693_charger_get_property(struct power_supply *psy,
 221                            enum power_supply_property psp,
 222                            union power_supply_propval *val)
 223{
 224        struct max77693_charger *chg = power_supply_get_drvdata(psy);
 225        struct regmap *regmap = chg->max77693->regmap;
 226        int ret = 0;
 227
 228        switch (psp) {
 229        case POWER_SUPPLY_PROP_STATUS:
 230                ret = max77693_get_charger_state(regmap, &val->intval);
 231                break;
 232        case POWER_SUPPLY_PROP_CHARGE_TYPE:
 233                ret = max77693_get_charge_type(regmap, &val->intval);
 234                break;
 235        case POWER_SUPPLY_PROP_HEALTH:
 236                ret = max77693_get_battery_health(regmap, &val->intval);
 237                break;
 238        case POWER_SUPPLY_PROP_PRESENT:
 239                ret = max77693_get_present(regmap, &val->intval);
 240                break;
 241        case POWER_SUPPLY_PROP_ONLINE:
 242                ret = max77693_get_online(regmap, &val->intval);
 243                break;
 244        case POWER_SUPPLY_PROP_MODEL_NAME:
 245                val->strval = max77693_charger_model;
 246                break;
 247        case POWER_SUPPLY_PROP_MANUFACTURER:
 248                val->strval = max77693_charger_manufacturer;
 249                break;
 250        default:
 251                return -EINVAL;
 252        }
 253
 254        return ret;
 255}
 256
 257static const struct power_supply_desc max77693_charger_desc = {
 258        .name           = MAX77693_CHARGER_NAME,
 259        .type           = POWER_SUPPLY_TYPE_BATTERY,
 260        .properties     = max77693_charger_props,
 261        .num_properties = ARRAY_SIZE(max77693_charger_props),
 262        .get_property   = max77693_charger_get_property,
 263};
 264
 265static ssize_t device_attr_store(struct device *dev,
 266                struct device_attribute *attr, const char *buf, size_t count,
 267                int (*fn)(struct max77693_charger *, unsigned long))
 268{
 269        struct max77693_charger *chg = dev_get_drvdata(dev);
 270        unsigned long val;
 271        int ret;
 272
 273        ret = kstrtoul(buf, 10, &val);
 274        if (ret)
 275                return ret;
 276
 277        ret = fn(chg, val);
 278        if (ret)
 279                return ret;
 280
 281        return count;
 282}
 283
 284static ssize_t fast_charge_timer_show(struct device *dev,
 285                struct device_attribute *attr, char *buf)
 286{
 287        struct max77693_charger *chg = dev_get_drvdata(dev);
 288        unsigned int data, val;
 289        int ret;
 290
 291        ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_01,
 292                        &data);
 293        if (ret < 0)
 294                return ret;
 295
 296        data &= CHG_CNFG_01_FCHGTIME_MASK;
 297        data >>= CHG_CNFG_01_FCHGTIME_SHIFT;
 298        switch (data) {
 299        case 0x1 ... 0x7:
 300                /* Starting from 4 hours, step by 2 hours */
 301                val = 4 + (data - 1) * 2;
 302                break;
 303        case 0x0:
 304        default:
 305                val = 0;
 306                break;
 307        }
 308
 309        return scnprintf(buf, PAGE_SIZE, "%u\n", val);
 310}
 311
 312static int max77693_set_fast_charge_timer(struct max77693_charger *chg,
 313                unsigned long hours)
 314{
 315        unsigned int data;
 316
 317        /*
 318         * 0x00 - disable
 319         * 0x01 - 4h
 320         * 0x02 - 6h
 321         * ...
 322         * 0x07 - 16h
 323         * Round down odd values.
 324         */
 325        switch (hours) {
 326        case 4 ... 16:
 327                data = (hours - 4) / 2 + 1;
 328                break;
 329        case 0:
 330                /* Disable */
 331                data = 0;
 332                break;
 333        default:
 334                return -EINVAL;
 335        }
 336        data <<= CHG_CNFG_01_FCHGTIME_SHIFT;
 337
 338        return regmap_update_bits(chg->max77693->regmap,
 339                        MAX77693_CHG_REG_CHG_CNFG_01,
 340                        CHG_CNFG_01_FCHGTIME_MASK, data);
 341}
 342
 343static ssize_t fast_charge_timer_store(struct device *dev,
 344                struct device_attribute *attr, const char *buf, size_t count)
 345{
 346        return device_attr_store(dev, attr, buf, count,
 347                        max77693_set_fast_charge_timer);
 348}
 349
 350static ssize_t top_off_threshold_current_show(struct device *dev,
 351                struct device_attribute *attr, char *buf)
 352{
 353        struct max77693_charger *chg = dev_get_drvdata(dev);
 354        unsigned int data, val;
 355        int ret;
 356
 357        ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03,
 358                        &data);
 359        if (ret < 0)
 360                return ret;
 361
 362        data &= CHG_CNFG_03_TOITH_MASK;
 363        data >>= CHG_CNFG_03_TOITH_SHIFT;
 364
 365        if (data <= 0x04)
 366                val = 100000 + data * 25000;
 367        else
 368                val = data * 50000;
 369
 370        return scnprintf(buf, PAGE_SIZE, "%u\n", val);
 371}
 372
 373static int max77693_set_top_off_threshold_current(struct max77693_charger *chg,
 374                unsigned long uamp)
 375{
 376        unsigned int data;
 377
 378        if (uamp < 100000 || uamp > 350000)
 379                return -EINVAL;
 380
 381        if (uamp <= 200000)
 382                data = (uamp - 100000) / 25000;
 383        else
 384                /* (200000, 350000> */
 385                data = uamp / 50000;
 386
 387        data <<= CHG_CNFG_03_TOITH_SHIFT;
 388
 389        return regmap_update_bits(chg->max77693->regmap,
 390                        MAX77693_CHG_REG_CHG_CNFG_03,
 391                        CHG_CNFG_03_TOITH_MASK, data);
 392}
 393
 394static ssize_t top_off_threshold_current_store(struct device *dev,
 395                struct device_attribute *attr, const char *buf, size_t count)
 396{
 397        return device_attr_store(dev, attr, buf, count,
 398                        max77693_set_top_off_threshold_current);
 399}
 400
 401static ssize_t top_off_timer_show(struct device *dev,
 402                struct device_attribute *attr, char *buf)
 403{
 404        struct max77693_charger *chg = dev_get_drvdata(dev);
 405        unsigned int data, val;
 406        int ret;
 407
 408        ret = regmap_read(chg->max77693->regmap, MAX77693_CHG_REG_CHG_CNFG_03,
 409                        &data);
 410        if (ret < 0)
 411                return ret;
 412
 413        data &= CHG_CNFG_03_TOTIME_MASK;
 414        data >>= CHG_CNFG_03_TOTIME_SHIFT;
 415
 416        val = data * 10;
 417
 418        return scnprintf(buf, PAGE_SIZE, "%u\n", val);
 419}
 420
 421static int max77693_set_top_off_timer(struct max77693_charger *chg,
 422                unsigned long minutes)
 423{
 424        unsigned int data;
 425
 426        if (minutes > 70)
 427                return -EINVAL;
 428
 429        data = minutes / 10;
 430        data <<= CHG_CNFG_03_TOTIME_SHIFT;
 431
 432        return regmap_update_bits(chg->max77693->regmap,
 433                        MAX77693_CHG_REG_CHG_CNFG_03,
 434                        CHG_CNFG_03_TOTIME_MASK, data);
 435}
 436
 437static ssize_t top_off_timer_store(struct device *dev,
 438                struct device_attribute *attr, const char *buf, size_t count)
 439{
 440        return device_attr_store(dev, attr, buf, count,
 441                        max77693_set_top_off_timer);
 442}
 443
 444static DEVICE_ATTR_RW(fast_charge_timer);
 445static DEVICE_ATTR_RW(top_off_threshold_current);
 446static DEVICE_ATTR_RW(top_off_timer);
 447
 448static int max77693_set_constant_volt(struct max77693_charger *chg,
 449                unsigned int uvolt)
 450{
 451        unsigned int data;
 452
 453        /*
 454         * 0x00 - 3.650 V
 455         * 0x01 - 3.675 V
 456         * ...
 457         * 0x1b - 4.325 V
 458         * 0x1c - 4.340 V
 459         * 0x1d - 4.350 V
 460         * 0x1e - 4.375 V
 461         * 0x1f - 4.400 V
 462         */
 463        if (uvolt >= 3650000 && uvolt < 4340000)
 464                data = (uvolt - 3650000) / 25000;
 465        else if (uvolt >= 4340000 && uvolt < 4350000)
 466                data = 0x1c;
 467        else if (uvolt >= 4350000 && uvolt <= 4400000)
 468                data = 0x1d + (uvolt - 4350000) / 25000;
 469        else {
 470                dev_err(chg->dev, "Wrong value for charging constant voltage\n");
 471                return -EINVAL;
 472        }
 473
 474        data <<= CHG_CNFG_04_CHGCVPRM_SHIFT;
 475
 476        dev_dbg(chg->dev, "Charging constant voltage: %u (0x%x)\n", uvolt,
 477                        data);
 478
 479        return regmap_update_bits(chg->max77693->regmap,
 480                        MAX77693_CHG_REG_CHG_CNFG_04,
 481                        CHG_CNFG_04_CHGCVPRM_MASK, data);
 482}
 483
 484static int max77693_set_min_system_volt(struct max77693_charger *chg,
 485                unsigned int uvolt)
 486{
 487        unsigned int data;
 488
 489        if (uvolt < 3000000 || uvolt > 3700000) {
 490                dev_err(chg->dev, "Wrong value for minimum system regulation voltage\n");
 491                return -EINVAL;
 492        }
 493
 494        data = (uvolt - 3000000) / 100000;
 495
 496        data <<= CHG_CNFG_04_MINVSYS_SHIFT;
 497
 498        dev_dbg(chg->dev, "Minimum system regulation voltage: %u (0x%x)\n",
 499                        uvolt, data);
 500
 501        return regmap_update_bits(chg->max77693->regmap,
 502                        MAX77693_CHG_REG_CHG_CNFG_04,
 503                        CHG_CNFG_04_MINVSYS_MASK, data);
 504}
 505
 506static int max77693_set_thermal_regulation_temp(struct max77693_charger *chg,
 507                unsigned int cels)
 508{
 509        unsigned int data;
 510
 511        switch (cels) {
 512        case 70:
 513        case 85:
 514        case 100:
 515        case 115:
 516                data = (cels - 70) / 15;
 517                break;
 518        default:
 519                dev_err(chg->dev, "Wrong value for thermal regulation loop temperature\n");
 520                return -EINVAL;
 521        }
 522
 523        data <<= CHG_CNFG_07_REGTEMP_SHIFT;
 524
 525        dev_dbg(chg->dev, "Thermal regulation loop temperature: %u (0x%x)\n",
 526                        cels, data);
 527
 528        return regmap_update_bits(chg->max77693->regmap,
 529                        MAX77693_CHG_REG_CHG_CNFG_07,
 530                        CHG_CNFG_07_REGTEMP_MASK, data);
 531}
 532
 533static int max77693_set_batttery_overcurrent(struct max77693_charger *chg,
 534                unsigned int uamp)
 535{
 536        unsigned int data;
 537
 538        if (uamp && (uamp < 2000000 || uamp > 3500000)) {
 539                dev_err(chg->dev, "Wrong value for battery overcurrent\n");
 540                return -EINVAL;
 541        }
 542
 543        if (uamp)
 544                data = ((uamp - 2000000) / 250000) + 1;
 545        else
 546                data = 0; /* disable */
 547
 548        data <<= CHG_CNFG_12_B2SOVRC_SHIFT;
 549
 550        dev_dbg(chg->dev, "Battery overcurrent: %u (0x%x)\n", uamp, data);
 551
 552        return regmap_update_bits(chg->max77693->regmap,
 553                        MAX77693_CHG_REG_CHG_CNFG_12,
 554                        CHG_CNFG_12_B2SOVRC_MASK, data);
 555}
 556
 557static int max77693_set_charge_input_threshold_volt(struct max77693_charger *chg,
 558                unsigned int uvolt)
 559{
 560        unsigned int data;
 561
 562        switch (uvolt) {
 563        case 4300000:
 564                data = 0x0;
 565                break;
 566        case 4700000:
 567        case 4800000:
 568        case 4900000:
 569                data = (uvolt - 4700000) / 100000;
 570        default:
 571                dev_err(chg->dev, "Wrong value for charge input voltage regulation threshold\n");
 572                return -EINVAL;
 573        }
 574
 575        data <<= CHG_CNFG_12_VCHGINREG_SHIFT;
 576
 577        dev_dbg(chg->dev, "Charge input voltage regulation threshold: %u (0x%x)\n",
 578                        uvolt, data);
 579
 580        return regmap_update_bits(chg->max77693->regmap,
 581                        MAX77693_CHG_REG_CHG_CNFG_12,
 582                        CHG_CNFG_12_VCHGINREG_MASK, data);
 583}
 584
 585/*
 586 * Sets charger registers to proper and safe default values.
 587 */
 588static int max77693_reg_init(struct max77693_charger *chg)
 589{
 590        int ret;
 591        unsigned int data;
 592
 593        /* Unlock charger register protection */
 594        data = (0x3 << CHG_CNFG_06_CHGPROT_SHIFT);
 595        ret = regmap_update_bits(chg->max77693->regmap,
 596                                MAX77693_CHG_REG_CHG_CNFG_06,
 597                                CHG_CNFG_06_CHGPROT_MASK, data);
 598        if (ret) {
 599                dev_err(chg->dev, "Error unlocking registers: %d\n", ret);
 600                return ret;
 601        }
 602
 603        ret = max77693_set_fast_charge_timer(chg, DEFAULT_FAST_CHARGE_TIMER);
 604        if (ret)
 605                return ret;
 606
 607        ret = max77693_set_top_off_threshold_current(chg,
 608                        DEFAULT_TOP_OFF_THRESHOLD_CURRENT);
 609        if (ret)
 610                return ret;
 611
 612        ret = max77693_set_top_off_timer(chg, DEFAULT_TOP_OFF_TIMER);
 613        if (ret)
 614                return ret;
 615
 616        ret = max77693_set_constant_volt(chg, chg->constant_volt);
 617        if (ret)
 618                return ret;
 619
 620        ret = max77693_set_min_system_volt(chg, chg->min_system_volt);
 621        if (ret)
 622                return ret;
 623
 624        ret = max77693_set_thermal_regulation_temp(chg,
 625                        chg->thermal_regulation_temp);
 626        if (ret)
 627                return ret;
 628
 629        ret = max77693_set_batttery_overcurrent(chg, chg->batttery_overcurrent);
 630        if (ret)
 631                return ret;
 632
 633        return max77693_set_charge_input_threshold_volt(chg,
 634                        chg->charge_input_threshold_volt);
 635}
 636
 637#ifdef CONFIG_OF
 638static int max77693_dt_init(struct device *dev, struct max77693_charger *chg)
 639{
 640        struct device_node *np = dev->of_node;
 641
 642        if (!np) {
 643                dev_err(dev, "no charger OF node\n");
 644                return -EINVAL;
 645        }
 646
 647        if (of_property_read_u32(np, "maxim,constant-microvolt",
 648                        &chg->constant_volt))
 649                chg->constant_volt = DEFAULT_CONSTANT_VOLT;
 650
 651        if (of_property_read_u32(np, "maxim,min-system-microvolt",
 652                        &chg->min_system_volt))
 653                chg->min_system_volt = DEFAULT_MIN_SYSTEM_VOLT;
 654
 655        if (of_property_read_u32(np, "maxim,thermal-regulation-celsius",
 656                        &chg->thermal_regulation_temp))
 657                chg->thermal_regulation_temp = DEFAULT_THERMAL_REGULATION_TEMP;
 658
 659        if (of_property_read_u32(np, "maxim,battery-overcurrent-microamp",
 660                        &chg->batttery_overcurrent))
 661                chg->batttery_overcurrent = DEFAULT_BATTERY_OVERCURRENT;
 662
 663        if (of_property_read_u32(np, "maxim,charge-input-threshold-microvolt",
 664                        &chg->charge_input_threshold_volt))
 665                chg->charge_input_threshold_volt =
 666                        DEFAULT_CHARGER_INPUT_THRESHOLD_VOLT;
 667
 668        return 0;
 669}
 670#else /* CONFIG_OF */
 671static int max77693_dt_init(struct device *dev, struct max77693_charger *chg)
 672{
 673        return 0;
 674}
 675#endif /* CONFIG_OF */
 676
 677static int max77693_charger_probe(struct platform_device *pdev)
 678{
 679        struct max77693_charger *chg;
 680        struct power_supply_config psy_cfg = {};
 681        struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
 682        int ret;
 683
 684        chg = devm_kzalloc(&pdev->dev, sizeof(*chg), GFP_KERNEL);
 685        if (!chg)
 686                return -ENOMEM;
 687
 688        platform_set_drvdata(pdev, chg);
 689        chg->dev = &pdev->dev;
 690        chg->max77693 = max77693;
 691
 692        ret = max77693_dt_init(&pdev->dev, chg);
 693        if (ret)
 694                return ret;
 695
 696        ret = max77693_reg_init(chg);
 697        if (ret)
 698                return ret;
 699
 700        psy_cfg.drv_data = chg;
 701
 702        ret = device_create_file(&pdev->dev, &dev_attr_fast_charge_timer);
 703        if (ret) {
 704                dev_err(&pdev->dev, "failed: create fast charge timer sysfs entry\n");
 705                goto err;
 706        }
 707
 708        ret = device_create_file(&pdev->dev,
 709                        &dev_attr_top_off_threshold_current);
 710        if (ret) {
 711                dev_err(&pdev->dev, "failed: create top off current sysfs entry\n");
 712                goto err;
 713        }
 714
 715        ret = device_create_file(&pdev->dev, &dev_attr_top_off_timer);
 716        if (ret) {
 717                dev_err(&pdev->dev, "failed: create top off timer sysfs entry\n");
 718                goto err;
 719        }
 720
 721        chg->charger = power_supply_register(&pdev->dev,
 722                                                &max77693_charger_desc,
 723                                                &psy_cfg);
 724        if (IS_ERR(chg->charger)) {
 725                dev_err(&pdev->dev, "failed: power supply register\n");
 726                ret = PTR_ERR(chg->charger);
 727                goto err;
 728        }
 729
 730        return 0;
 731
 732err:
 733        device_remove_file(&pdev->dev, &dev_attr_top_off_timer);
 734        device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current);
 735        device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
 736
 737        return ret;
 738}
 739
 740static int max77693_charger_remove(struct platform_device *pdev)
 741{
 742        struct max77693_charger *chg = platform_get_drvdata(pdev);
 743
 744        device_remove_file(&pdev->dev, &dev_attr_top_off_timer);
 745        device_remove_file(&pdev->dev, &dev_attr_top_off_threshold_current);
 746        device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
 747
 748        power_supply_unregister(chg->charger);
 749
 750        return 0;
 751}
 752
 753static const struct platform_device_id max77693_charger_id[] = {
 754        { "max77693-charger", 0, },
 755        { }
 756};
 757MODULE_DEVICE_TABLE(platform, max77693_charger_id);
 758
 759static struct platform_driver max77693_charger_driver = {
 760        .driver = {
 761                .name   = "max77693-charger",
 762        },
 763        .probe          = max77693_charger_probe,
 764        .remove         = max77693_charger_remove,
 765        .id_table       = max77693_charger_id,
 766};
 767module_platform_driver(max77693_charger_driver);
 768
 769MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
 770MODULE_DESCRIPTION("Maxim 77693 charger driver");
 771MODULE_LICENSE("GPL");
 772