drivers/power/supply/sc27xx_fuel_gauge.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2018 Spreadtrum Communications Inc.
   3
   4 #include <linux/gpio/consumer.h>
   5 #include <linux/iio/consumer.h>
   6 #include <linux/interrupt.h>
   7 #include <linux/kernel.h>
   8 #include <linux/module.h>
   9 #include <linux/nvmem-consumer.h>
  10 #include <linux/of.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/power_supply.h>
  13 #include <linux/regmap.h>
  14 #include <linux/slab.h>
  15
  16 /* PMIC global control registers definition */
  17 #define SC27XX_MODULE_EN0               0xc08
  18 #define SC27XX_CLK_EN0                  0xc18
  19 #define SC27XX_FGU_EN                   BIT(7)
  20 #define SC27XX_FGU_RTC_EN               BIT(6)
  21
  22 /* FGU registers definition */
  23 #define SC27XX_FGU_START                0x0
  24 #define SC27XX_FGU_CONFIG               0x4
  25 #define SC27XX_FGU_ADC_CONFIG           0x8
  26 #define SC27XX_FGU_STATUS               0xc
  27 #define SC27XX_FGU_INT_EN               0x10
  28 #define SC27XX_FGU_INT_CLR              0x14
  29 #define SC27XX_FGU_INT_STS              0x1c
  30 #define SC27XX_FGU_VOLTAGE              0x20
  31 #define SC27XX_FGU_OCV                  0x24
  32 #define SC27XX_FGU_POCV                 0x28
  33 #define SC27XX_FGU_CURRENT              0x2c
  34 #define SC27XX_FGU_LOW_OVERLOAD         0x34
  35 #define SC27XX_FGU_CLBCNT_SETH          0x50
  36 #define SC27XX_FGU_CLBCNT_SETL          0x54
  37 #define SC27XX_FGU_CLBCNT_DELTH         0x58
  38 #define SC27XX_FGU_CLBCNT_DELTL         0x5c
  39 #define SC27XX_FGU_CLBCNT_VALH          0x68
  40 #define SC27XX_FGU_CLBCNT_VALL          0x6c
  41 #define SC27XX_FGU_CLBCNT_QMAXL         0x74
  42 #define SC27XX_FGU_USER_AREA_SET        0xa0
  43 #define SC27XX_FGU_USER_AREA_CLEAR      0xa4
  44 #define SC27XX_FGU_USER_AREA_STATUS     0xa8
  45
  46 #define SC27XX_WRITE_SELCLB_EN          BIT(0)
  47 #define SC27XX_FGU_CLBCNT_MASK          GENMASK(15, 0)
  48 #define SC27XX_FGU_CLBCNT_SHIFT         16
  49 #define SC27XX_FGU_LOW_OVERLOAD_MASK    GENMASK(12, 0)
  50
  51 #define SC27XX_FGU_INT_MASK             GENMASK(9, 0)
  52 #define SC27XX_FGU_LOW_OVERLOAD_INT     BIT(0)
  53 #define SC27XX_FGU_CLBCNT_DELTA_INT     BIT(2)
  54
  55 #define SC27XX_FGU_MODE_AREA_MASK       GENMASK(15, 12)
  56 #define SC27XX_FGU_CAP_AREA_MASK        GENMASK(11, 0)
  57 #define SC27XX_FGU_MODE_AREA_SHIFT      12
  58
  59 #define SC27XX_FGU_FIRST_POWERTON       GENMASK(3, 0)
  60 #define SC27XX_FGU_DEFAULT_CAP          GENMASK(11, 0)
  61 #define SC27XX_FGU_NORMAIL_POWERTON     0x5
  62
  63 #define SC27XX_FGU_CUR_BASIC_ADC        8192
  64 #define SC27XX_FGU_SAMPLE_HZ            2
  65
  66 /*
  67  * struct sc27xx_fgu_data: describe the FGU device
  68  * @regmap: regmap for register access
  69  * @dev: platform device
  70  * @battery: battery power supply
  71  * @base: the base offset for the controller
  72  * @lock: protect the structure
  73  * @gpiod: GPIO for battery detection
  74  * @channel: IIO channel to get battery temperature
  75  * @charge_chan: IIO channel to get charge voltage
  76  * @internal_resist: the battery internal resistance in mOhm
  77  * @total_cap: the total capacity of the battery in mAh
  78  * @init_cap: the initial capacity of the battery in mAh
  79  * @alarm_cap: the alarm capacity
  80  * @init_clbcnt: the initial coulomb counter
  81  * @max_volt: the maximum constant input voltage in millivolt
  82  * @min_volt: the minimum drained battery voltage in microvolt
  83  * @table_len: the capacity table length
  84  * @cur_1000ma_adc: ADC value corresponding to 1000 mA
  85  * @vol_1000mv_adc: ADC value corresponding to 1000 mV
  86  * @cap_table: capacity table with corresponding ocv
  87  */
  88 struct sc27xx_fgu_data {
  89         struct regmap *regmap;
  90         struct device *dev;
  91         struct power_supply *battery;
  92         u32 base;
  93         struct mutex lock;
  94         struct gpio_desc *gpiod;
  95         struct iio_channel *channel;
  96         struct iio_channel *charge_chan;
  97         bool bat_present;
  98         int internal_resist;
  99         int total_cap;
 100         int init_cap;
 101         int alarm_cap;
 102         int init_clbcnt;
 103         int max_volt;
 104         int min_volt;
 105         int table_len;
 106         int cur_1000ma_adc;
 107         int vol_1000mv_adc;
 108         struct power_supply_battery_ocv_table *cap_table;
 109 };
 110
 111 static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity);
 112
 113 static const char * const sc27xx_charger_supply_name[] = {
 114         "sc2731_charger",
 115         "sc2720_charger",
 116         "sc2721_charger",
 117         "sc2723_charger",
 118 };
 119
 120 static int sc27xx_fgu_adc_to_current(struct sc27xx_fgu_data *data, int adc)
 121 {
 122         return DIV_ROUND_CLOSEST(adc * 1000, data->cur_1000ma_adc);
 123 }
 124
 125 static int sc27xx_fgu_adc_to_voltage(struct sc27xx_fgu_data *data, int adc)
 126 {
 127         return DIV_ROUND_CLOSEST(adc * 1000, data->vol_1000mv_adc);
 128 }
 129
 130 static int sc27xx_fgu_voltage_to_adc(struct sc27xx_fgu_data *data, int vol)
 131 {
 132         return DIV_ROUND_CLOSEST(vol * data->vol_1000mv_adc, 1000);
 133 }
 134
 135 static bool sc27xx_fgu_is_first_poweron(struct sc27xx_fgu_data *data)
 136 {
 137         int ret, status, cap, mode;
 138
 139         ret = regmap_read(data->regmap,
 140                           data->base + SC27XX_FGU_USER_AREA_STATUS, &status);
 141         if (ret)
 142                 return false;
 143
 144         /*
 145          * We use low 4 bits to save the last battery capacity and high 12 bits
 146          * to save the system boot mode.
 147          */
 148         mode = (status & SC27XX_FGU_MODE_AREA_MASK) >> SC27XX_FGU_MODE_AREA_SHIFT;
 149         cap = status & SC27XX_FGU_CAP_AREA_MASK;
 150
 151         /*
 152          * When FGU has been powered down, the user area registers became
 153          * default value (0xffff), which can be used to valid if the system is
 154          * first power on or not.
 155          */
 156         if (mode == SC27XX_FGU_FIRST_POWERTON || cap == SC27XX_FGU_DEFAULT_CAP)
 157                 return true;
 158
 159         return false;
 160 }
 161
 162 static int sc27xx_fgu_save_boot_mode(struct sc27xx_fgu_data *data,
 163                                      int boot_mode)
 164 {
 165         int ret;
 166
 167         ret = regmap_update_bits(data->regmap,
 168                                  data->base + SC27XX_FGU_USER_AREA_CLEAR,
 169                                  SC27XX_FGU_MODE_AREA_MASK,
 170                                  SC27XX_FGU_MODE_AREA_MASK);
 171         if (ret)
 172                 return ret;
 173
 174         /*
 175          * Since the user area registers are put on power always-on region,
 176          * then these registers changing time will be a little long. Thus
 177          * here we should delay 200us to wait until values are updated
 178          * successfully according to the datasheet.
 179          */
 180         udelay(200);
 181
 182         ret = regmap_update_bits(data->regmap,
 183                                  data->base + SC27XX_FGU_USER_AREA_SET,
 184                                  SC27XX_FGU_MODE_AREA_MASK,
 185                                  boot_mode << SC27XX_FGU_MODE_AREA_SHIFT);
 186         if (ret)
 187                 return ret;
 188
 189         /*
 190          * Since the user area registers are put on power always-on region,
 191          * then these registers changing time will be a little long. Thus
 192          * here we should delay 200us to wait until values are updated
 193          * successfully according to the datasheet.
 194          */
 195         udelay(200);
 196
 197         /*
 198          * According to the datasheet, we should set the USER_AREA_CLEAR to 0 to
 199          * make the user area data available, otherwise we can not save the user
 200          * area data.
 201          */
 202         return regmap_update_bits(data->regmap,
 203                                   data->base + SC27XX_FGU_USER_AREA_CLEAR,
 204                                   SC27XX_FGU_MODE_AREA_MASK, 0);
 205 }
 206
 207 static int sc27xx_fgu_save_last_cap(struct sc27xx_fgu_data *data, int cap)
 208 {
 209         int ret;
 210
 211         ret = regmap_update_bits(data->regmap,
 212                                  data->base + SC27XX_FGU_USER_AREA_CLEAR,
 213                                  SC27XX_FGU_CAP_AREA_MASK,
 214                                  SC27XX_FGU_CAP_AREA_MASK);
 215         if (ret)
 216                 return ret;
 217
 218         /*
 219          * Since the user area registers are put on power always-on region,
 220          * then these registers changing time will be a little long. Thus
 221          * here we should delay 200us to wait until values are updated
 222          * successfully according to the datasheet.
 223          */
 224         udelay(200);
 225
 226         ret = regmap_update_bits(data->regmap,
 227                                  data->base + SC27XX_FGU_USER_AREA_SET,
 228                                  SC27XX_FGU_CAP_AREA_MASK, cap);
 229         if (ret)
 230                 return ret;
 231
 232         /*
 233          * Since the user area registers are put on power always-on region,
 234          * then these registers changing time will be a little long. Thus
 235          * here we should delay 200us to wait until values are updated
 236          * successfully according to the datasheet.
 237          */
 238         udelay(200);
 239
 240         /*
 241          * According to the datasheet, we should set the USER_AREA_CLEAR to 0 to
 242          * make the user area data available, otherwise we can not save the user
 243          * area data.
 244          */
 245         return regmap_update_bits(data->regmap,
 246                                   data->base + SC27XX_FGU_USER_AREA_CLEAR,
 247                                   SC27XX_FGU_CAP_AREA_MASK, 0);
 248 }
 249
 250 static int sc27xx_fgu_read_last_cap(struct sc27xx_fgu_data *data, int *cap)
 251 {
 252         int ret, value;
 253
 254         ret = regmap_read(data->regmap,
 255                           data->base + SC27XX_FGU_USER_AREA_STATUS, &value);
 256         if (ret)
 257                 return ret;
 258
 259         *cap = value & SC27XX_FGU_CAP_AREA_MASK;
 260         return 0;
 261 }
 262
 263 /*
 264  * When system boots on, we can not read battery capacity from coulomb
 265  * registers, since now the coulomb registers are invalid. So we should
 266  * calculate the battery open circuit voltage, and get current battery
 267  * capacity according to the capacity table.
 268  */
 269 static int sc27xx_fgu_get_boot_capacity(struct sc27xx_fgu_data *data, int *cap)
 270 {
 271         int volt, cur, oci, ocv, ret;
 272         bool is_first_poweron = sc27xx_fgu_is_first_poweron(data);
 273
 274         /*
 275          * If system is not the first power on, we should use the last saved
 276          * battery capacity as the initial battery capacity. Otherwise we should
 277          * re-calculate the initial battery capacity.
 278          */
 279         if (!is_first_poweron) {
 280                 ret = sc27xx_fgu_read_last_cap(data, cap);
 281                 if (ret)
 282                         return ret;
 283
 284                 return sc27xx_fgu_save_boot_mode(data, SC27XX_FGU_NORMAIL_POWERTON);
 285         }
 286
 287         /*
 288          * After system booting on, the SC27XX_FGU_CLBCNT_QMAXL register saved
 289          * the first sampled open circuit current.
 290          */
 291         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_QMAXL,
 292                           &cur);
 293         if (ret)
 294                 return ret;
 295
 296         cur <<= 1;
 297         oci = sc27xx_fgu_adc_to_current(data, cur - SC27XX_FGU_CUR_BASIC_ADC);
 298
 299         /*
 300          * Should get the OCV from SC27XX_FGU_POCV register at the system
 301          * beginning. It is ADC values reading from registers which need to
 302          * convert the corresponding voltage.
 303          */
 304         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_POCV, &volt);
 305         if (ret)
 306                 return ret;
 307
 308         volt = sc27xx_fgu_adc_to_voltage(data, volt);
 309         ocv = volt * 1000 - oci * data->internal_resist;
 310
 311         /*
 312          * Parse the capacity table to look up the correct capacity percent
 313          * according to current battery's corresponding OCV values.
 314          */
 315         *cap = power_supply_ocv2cap_simple(data->cap_table, data->table_len,
 316                                            ocv);
 317
 318         ret = sc27xx_fgu_save_last_cap(data, *cap);
 319         if (ret)
 320                 return ret;
 321
 322         return sc27xx_fgu_save_boot_mode(data, SC27XX_FGU_NORMAIL_POWERTON);
 323 }
 324
 325 static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt)
 326 {
 327         int ret;
 328
 329         clbcnt *= SC27XX_FGU_SAMPLE_HZ;
 330
 331         ret = regmap_update_bits(data->regmap,
 332                                  data->base + SC27XX_FGU_CLBCNT_SETL,
 333                                  SC27XX_FGU_CLBCNT_MASK, clbcnt);
 334         if (ret)
 335                 return ret;
 336
 337         ret = regmap_update_bits(data->regmap,
 338                                  data->base + SC27XX_FGU_CLBCNT_SETH,
 339                                  SC27XX_FGU_CLBCNT_MASK,
 340                                  clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
 341         if (ret)
 342                 return ret;
 343
 344         return regmap_update_bits(data->regmap, data->base + SC27XX_FGU_START,
 345                                  SC27XX_WRITE_SELCLB_EN,
 346                                  SC27XX_WRITE_SELCLB_EN);
 347 }
 348
 349 static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt)
 350 {
 351         int ccl, cch, ret;
 352
 353         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALL,
 354                           &ccl);
 355         if (ret)
 356                 return ret;
 357
 358         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CLBCNT_VALH,
 359                           &cch);
 360         if (ret)
 361                 return ret;
 362
 363         *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK;
 364         *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT;
 365         *clb_cnt /= SC27XX_FGU_SAMPLE_HZ;
 366
 367         return 0;
 368 }
 369
 370 static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap)
 371 {
 372         int ret, cur_clbcnt, delta_clbcnt, delta_cap, temp;
 373
 374         /* Get current coulomb counters firstly */
 375         ret = sc27xx_fgu_get_clbcnt(data, &cur_clbcnt);
 376         if (ret)
 377                 return ret;
 378
 379         delta_clbcnt = cur_clbcnt - data->init_clbcnt;
 380
 381         /*
 382          * Convert coulomb counter to delta capacity (mAh), and set multiplier
 383          * as 100 to improve the precision.
 384          */
 385         temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360);
 386         temp = sc27xx_fgu_adc_to_current(data, temp);
 387
 388         /*
 389          * Convert to capacity percent of the battery total capacity,
 390          * and multiplier is 100 too.
 391          */
 392         delta_cap = DIV_ROUND_CLOSEST(temp * 100, data->total_cap);
 393         *cap = delta_cap + data->init_cap;
 394
 395         return 0;
 396 }
 397
 398 static int sc27xx_fgu_get_vbat_vol(struct sc27xx_fgu_data *data, int *val)
 399 {
 400         int ret, vol;
 401
 402         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_VOLTAGE, &vol);
 403         if (ret)
 404                 return ret;
 405
 406         /*
 407          * It is ADC values reading from registers which need to convert to
 408          * corresponding voltage values.
 409          */
 410         *val = sc27xx_fgu_adc_to_voltage(data, vol);
 411
 412         return 0;
 413 }
 414
 415 static int sc27xx_fgu_get_current(struct sc27xx_fgu_data *data, int *val)
 416 {
 417         int ret, cur;
 418
 419         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_CURRENT, &cur);
 420         if (ret)
 421                 return ret;
 422
 423         /*
 424          * It is ADC values reading from registers which need to convert to
 425          * corresponding current values.
 426          */
 427         *val = sc27xx_fgu_adc_to_current(data, cur - SC27XX_FGU_CUR_BASIC_ADC);
 428
 429         return 0;
 430 }
 431
 432 static int sc27xx_fgu_get_vbat_ocv(struct sc27xx_fgu_data *data, int *val)
 433 {
 434         int vol, cur, ret;
 435
 436         ret = sc27xx_fgu_get_vbat_vol(data, &vol);
 437         if (ret)
 438                 return ret;
 439
 440         ret = sc27xx_fgu_get_current(data, &cur);
 441         if (ret)
 442                 return ret;
 443
 444         /* Return the battery OCV in micro volts. */
 445         *val = vol * 1000 - cur * data->internal_resist;
 446
 447         return 0;
 448 }
 449
 450 static int sc27xx_fgu_get_charge_vol(struct sc27xx_fgu_data *data, int *val)
 451 {
 452         int ret, vol;
 453
 454         ret = iio_read_channel_processed(data->charge_chan, &vol);
 455         if (ret < 0)
 456                 return ret;
 457
 458         *val = vol * 1000;
 459         return 0;
 460 }
 461
 462 static int sc27xx_fgu_get_temp(struct sc27xx_fgu_data *data, int *temp)
 463 {
 464         return iio_read_channel_processed(data->channel, temp);
 465 }
 466
 467 static int sc27xx_fgu_get_health(struct sc27xx_fgu_data *data, int *health)
 468 {
 469         int ret, vol;
 470
 471         ret = sc27xx_fgu_get_vbat_vol(data, &vol);
 472         if (ret)
 473                 return ret;
 474
 475         if (vol > data->max_volt)
 476                 *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 477         else
 478                 *health = POWER_SUPPLY_HEALTH_GOOD;
 479
 480         return 0;
 481 }
 482
 483 static int sc27xx_fgu_get_status(struct sc27xx_fgu_data *data, int *status)
 484 {
 485         union power_supply_propval val;
 486         struct power_supply *psy;
 487         int i, ret = -EINVAL;
 488
 489         for (i = 0; i < ARRAY_SIZE(sc27xx_charger_supply_name); i++) {
 490                 psy = power_supply_get_by_name(sc27xx_charger_supply_name[i]);
 491                 if (!psy)
 492                         continue;
 493
 494                 ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS,
 495                                                 &val);
 496                 power_supply_put(psy);
 497                 if (ret)
 498                         return ret;
 499
 500                 *status = val.intval;
 501         }
 502
 503         return ret;
 504 }
 505
 506 static int sc27xx_fgu_get_property(struct power_supply *psy,
 507                                    enum power_supply_property psp,
 508                                    union power_supply_propval *val)
 509 {
 510         struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
 511         int ret = 0;
 512         int value;
 513
 514         mutex_lock(&data->lock);
 515
 516         switch (psp) {
 517         case POWER_SUPPLY_PROP_STATUS:
 518                 ret = sc27xx_fgu_get_status(data, &value);
 519                 if (ret)
 520                         goto error;
 521
 522                 val->intval = value;
 523                 break;
 524
 525         case POWER_SUPPLY_PROP_HEALTH:
 526                 ret = sc27xx_fgu_get_health(data, &value);
 527                 if (ret)
 528                         goto error;
 529
 530                 val->intval = value;
 531                 break;
 532
 533         case POWER_SUPPLY_PROP_PRESENT:
 534                 val->intval = data->bat_present;
 535                 break;
 536
 537         case POWER_SUPPLY_PROP_TEMP:
 538                 ret = sc27xx_fgu_get_temp(data, &value);
 539                 if (ret)
 540                         goto error;
 541
 542                 val->intval = value;
 543                 break;
 544
 545         case POWER_SUPPLY_PROP_TECHNOLOGY:
 546                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 547                 break;
 548
 549         case POWER_SUPPLY_PROP_CAPACITY:
 550                 ret = sc27xx_fgu_get_capacity(data, &value);
 551                 if (ret)
 552                         goto error;
 553
 554                 val->intval = value;
 555                 break;
 556
 557         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 558                 ret = sc27xx_fgu_get_vbat_vol(data, &value);
 559                 if (ret)
 560                         goto error;
 561
 562                 val->intval = value * 1000;
 563                 break;
 564
 565         case POWER_SUPPLY_PROP_VOLTAGE_OCV:
 566                 ret = sc27xx_fgu_get_vbat_ocv(data, &value);
 567                 if (ret)
 568                         goto error;
 569
 570                 val->intval = value;
 571                 break;
 572
 573         case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
 574                 ret = sc27xx_fgu_get_charge_vol(data, &value);
 575                 if (ret)
 576                         goto error;
 577
 578                 val->intval = value;
 579                 break;
 580
 581         case POWER_SUPPLY_PROP_CURRENT_NOW:
 582         case POWER_SUPPLY_PROP_CURRENT_AVG:
 583                 ret = sc27xx_fgu_get_current(data, &value);
 584                 if (ret)
 585                         goto error;
 586
 587                 val->intval = value * 1000;
 588                 break;
 589
 590         default:
 591                 ret = -EINVAL;
 592                 break;
 593         }
 594
 595 error:
 596         mutex_unlock(&data->lock);
 597         return ret;
 598 }
 599
 600 static int sc27xx_fgu_set_property(struct power_supply *psy,
 601                                    enum power_supply_property psp,
 602                                    const union power_supply_propval *val)
 603 {
 604         struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
 605         int ret;
 606
 607         if (psp != POWER_SUPPLY_PROP_CAPACITY)
 608                 return -EINVAL;
 609
 610         mutex_lock(&data->lock);
 611
 612         ret = sc27xx_fgu_save_last_cap(data, val->intval);
 613
 614         mutex_unlock(&data->lock);
 615
 616         if (ret < 0)
 617                 dev_err(data->dev, "failed to save battery capacity\n");
 618
 619         return ret;
 620 }
 621
 622 static void sc27xx_fgu_external_power_changed(struct power_supply *psy)
 623 {
 624         struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy);
 625
 626         power_supply_changed(data->battery);
 627 }
 628
 629 static int sc27xx_fgu_property_is_writeable(struct power_supply *psy,
 630                                             enum power_supply_property psp)
 631 {
 632         return psp == POWER_SUPPLY_PROP_CAPACITY;
 633 }
 634
 635 static enum power_supply_property sc27xx_fgu_props[] = {
 636         POWER_SUPPLY_PROP_STATUS,
 637         POWER_SUPPLY_PROP_HEALTH,
 638         POWER_SUPPLY_PROP_PRESENT,
 639         POWER_SUPPLY_PROP_TEMP,
 640         POWER_SUPPLY_PROP_TECHNOLOGY,
 641         POWER_SUPPLY_PROP_CAPACITY,
 642         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 643         POWER_SUPPLY_PROP_VOLTAGE_OCV,
 644         POWER_SUPPLY_PROP_CURRENT_NOW,
 645         POWER_SUPPLY_PROP_CURRENT_AVG,
 646         POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
 647 };
 648
 649 static const struct power_supply_desc sc27xx_fgu_desc = {
 650         .name                   = "sc27xx-fgu",
 651         .type                   = POWER_SUPPLY_TYPE_BATTERY,
 652         .properties             = sc27xx_fgu_props,
 653         .num_properties         = ARRAY_SIZE(sc27xx_fgu_props),
 654         .get_property           = sc27xx_fgu_get_property,
 655         .set_property           = sc27xx_fgu_set_property,
 656         .external_power_changed = sc27xx_fgu_external_power_changed,
 657         .property_is_writeable  = sc27xx_fgu_property_is_writeable,
 658 };
 659
 660 static void sc27xx_fgu_adjust_cap(struct sc27xx_fgu_data *data, int cap)
 661 {
 662         data->init_cap = cap;
 663         data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
 664 }
 665
 666 static irqreturn_t sc27xx_fgu_interrupt(int irq, void *dev_id)
 667 {
 668         struct sc27xx_fgu_data *data = dev_id;
 669         int ret, cap, ocv, adc;
 670         u32 status;
 671
 672         mutex_lock(&data->lock);
 673
 674         ret = regmap_read(data->regmap, data->base + SC27XX_FGU_INT_STS,
 675                           &status);
 676         if (ret)
 677                 goto out;
 678
 679         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
 680                                  status, status);
 681         if (ret)
 682                 goto out;
 683
 684         /*
 685          * When low overload voltage interrupt happens, we should calibrate the
 686          * battery capacity in lower voltage stage.
 687          */
 688         if (!(status & SC27XX_FGU_LOW_OVERLOAD_INT))
 689                 goto out;
 690
 691         ret = sc27xx_fgu_get_capacity(data, &cap);
 692         if (ret)
 693                 goto out;
 694
 695         ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
 696         if (ret)
 697                 goto out;
 698
 699         /*
 700          * If current OCV value is less than the minimum OCV value in OCV table,
 701          * which means now battery capacity is 0%, and we should adjust the
 702          * inititial capacity to 0.
 703          */
 704         if (ocv <= data->cap_table[data->table_len - 1].ocv) {
 705                 sc27xx_fgu_adjust_cap(data, 0);
 706         } else if (ocv <= data->min_volt) {
 707                 /*
 708                  * If current OCV value is less than the low alarm voltage, but
 709                  * current capacity is larger than the alarm capacity, we should
 710                  * adjust the inititial capacity to alarm capacity.
 711                  */
 712                 if (cap > data->alarm_cap) {
 713                         sc27xx_fgu_adjust_cap(data, data->alarm_cap);
 714                 } else if (cap <= 0) {
 715                         int cur_cap;
 716
 717                         /*
 718                          * If current capacity is equal with 0 or less than 0
 719                          * (some error occurs), we should adjust inititial
 720                          * capacity to the capacity corresponding to current OCV
 721                          * value.
 722                          */
 723                         cur_cap = power_supply_ocv2cap_simple(data->cap_table,
 724                                                               data->table_len,
 725                                                               ocv);
 726                         sc27xx_fgu_adjust_cap(data, cur_cap);
 727                 }
 728
 729                 /*
 730                  * After adjusting the battery capacity, we should set the
 731                  * lowest alarm voltage instead.
 732                  */
 733                 data->min_volt = data->cap_table[data->table_len - 1].ocv;
 734                 adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
 735                 regmap_update_bits(data->regmap, data->base + SC27XX_FGU_LOW_OVERLOAD,
 736                                    SC27XX_FGU_LOW_OVERLOAD_MASK, adc);
 737         }
 738
 739 out:
 740         mutex_unlock(&data->lock);
 741
 742         power_supply_changed(data->battery);
 743         return IRQ_HANDLED;
 744 }
 745
 746 static irqreturn_t sc27xx_fgu_bat_detection(int irq, void *dev_id)
 747 {
 748         struct sc27xx_fgu_data *data = dev_id;
 749         int state;
 750
 751         mutex_lock(&data->lock);
 752
 753         state = gpiod_get_value_cansleep(data->gpiod);
 754         if (state < 0) {
 755                 dev_err(data->dev, "failed to get gpio state\n");
 756                 mutex_unlock(&data->lock);
 757                 return IRQ_RETVAL(state);
 758         }
 759
 760         data->bat_present = !!state;
 761
 762         mutex_unlock(&data->lock);
 763
 764         power_supply_changed(data->battery);
 765         return IRQ_HANDLED;
 766 }
 767
 768 static void sc27xx_fgu_disable(void *_data)
 769 {
 770         struct sc27xx_fgu_data *data = _data;
 771
 772         regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
 773         regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
 774 }
 775
 776 static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity)
 777 {
 778         /*
 779          * Get current capacity (mAh) = battery total capacity (mAh) *
 780          * current capacity percent (capacity / 100).
 781          */
 782         int cur_cap = DIV_ROUND_CLOSEST(data->total_cap * capacity, 100);
 783
 784         /*
 785          * Convert current capacity (mAh) to coulomb counter according to the
 786          * formula: 1 mAh =3.6 coulomb.
 787          */
 788         return DIV_ROUND_CLOSEST(cur_cap * 36 * data->cur_1000ma_adc, 10);
 789 }
 790
 791 static int sc27xx_fgu_calibration(struct sc27xx_fgu_data *data)
 792 {
 793         struct nvmem_cell *cell;
 794         int calib_data, cal_4200mv;
 795         void *buf;
 796         size_t len;
 797
 798         cell = nvmem_cell_get(data->dev, "fgu_calib");
 799         if (IS_ERR(cell))
 800                 return PTR_ERR(cell);
 801
 802         buf = nvmem_cell_read(cell, &len);
 803         nvmem_cell_put(cell);
 804
 805         if (IS_ERR(buf))
 806                 return PTR_ERR(buf);
 807
 808         memcpy(&calib_data, buf, min(len, sizeof(u32)));
 809
 810         /*
 811          * Get the ADC value corresponding to 4200 mV from eFuse controller
 812          * according to below formula. Then convert to ADC values corresponding
 813          * to 1000 mV and 1000 mA.
 814          */
 815         cal_4200mv = (calib_data & 0x1ff) + 6963 - 4096 - 256;
 816         data->vol_1000mv_adc = DIV_ROUND_CLOSEST(cal_4200mv * 10, 42);
 817         data->cur_1000ma_adc = data->vol_1000mv_adc * 4;
 818
 819         kfree(buf);
 820         return 0;
 821 }
 822
 823 static int sc27xx_fgu_hw_init(struct sc27xx_fgu_data *data)
 824 {
 825         struct power_supply_battery_info info = { };
 826         struct power_supply_battery_ocv_table *table;
 827         int ret, delta_clbcnt, alarm_adc;
 828
 829         ret = power_supply_get_battery_info(data->battery, &info);
 830         if (ret) {
 831                 dev_err(data->dev, "failed to get battery information\n");
 832                 return ret;
 833         }
 834
 835         data->total_cap = info.charge_full_design_uah / 1000;
 836         data->max_volt = info.constant_charge_voltage_max_uv / 1000;
 837         data->internal_resist = info.factory_internal_resistance_uohm / 1000;
 838         data->min_volt = info.voltage_min_design_uv;
 839
 840         /*
 841          * For SC27XX fuel gauge device, we only use one ocv-capacity
 842          * table in normal temperature 20 Celsius.
 843          */
 844         table = power_supply_find_ocv2cap_table(&info, 20, &data->table_len);
 845         if (!table)
 846                 return -EINVAL;
 847
 848         data->cap_table = devm_kmemdup(data->dev, table,
 849                                        data->table_len * sizeof(*table),
 850                                        GFP_KERNEL);
 851         if (!data->cap_table) {
 852                 power_supply_put_battery_info(data->battery, &info);
 853                 return -ENOMEM;
 854         }
 855
 856         data->alarm_cap = power_supply_ocv2cap_simple(data->cap_table,
 857                                                       data->table_len,
 858                                                       data->min_volt);
 859
 860         power_supply_put_battery_info(data->battery, &info);
 861
 862         ret = sc27xx_fgu_calibration(data);
 863         if (ret)
 864                 return ret;
 865
 866         /* Enable the FGU module */
 867         ret = regmap_update_bits(data->regmap, SC27XX_MODULE_EN0,
 868                                  SC27XX_FGU_EN, SC27XX_FGU_EN);
 869         if (ret) {
 870                 dev_err(data->dev, "failed to enable fgu\n");
 871                 return ret;
 872         }
 873
 874         /* Enable the FGU RTC clock to make it work */
 875         ret = regmap_update_bits(data->regmap, SC27XX_CLK_EN0,
 876                                  SC27XX_FGU_RTC_EN, SC27XX_FGU_RTC_EN);
 877         if (ret) {
 878                 dev_err(data->dev, "failed to enable fgu RTC clock\n");
 879                 goto disable_fgu;
 880         }
 881
 882         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_CLR,
 883                                  SC27XX_FGU_INT_MASK, SC27XX_FGU_INT_MASK);
 884         if (ret) {
 885                 dev_err(data->dev, "failed to clear interrupt status\n");
 886                 goto disable_clk;
 887         }
 888
 889         /*
 890          * Set the voltage low overload threshold, which means when the battery
 891          * voltage is lower than this threshold, the controller will generate
 892          * one interrupt to notify.
 893          */
 894         alarm_adc = sc27xx_fgu_voltage_to_adc(data, data->min_volt / 1000);
 895         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_LOW_OVERLOAD,
 896                                  SC27XX_FGU_LOW_OVERLOAD_MASK, alarm_adc);
 897         if (ret) {
 898                 dev_err(data->dev, "failed to set fgu low overload\n");
 899                 goto disable_clk;
 900         }
 901
 902         /*
 903          * Set the coulomb counter delta threshold, that means when the coulomb
 904          * counter change is multiples of the delta threshold, the controller
 905          * will generate one interrupt to notify the users to update the battery
 906          * capacity. Now we set the delta threshold as a counter value of 1%
 907          * capacity.
 908          */
 909         delta_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, 1);
 910
 911         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_DELTL,
 912                                  SC27XX_FGU_CLBCNT_MASK, delta_clbcnt);
 913         if (ret) {
 914                 dev_err(data->dev, "failed to set low delta coulomb counter\n");
 915                 goto disable_clk;
 916         }
 917
 918         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_DELTH,
 919                                  SC27XX_FGU_CLBCNT_MASK,
 920                                  delta_clbcnt >> SC27XX_FGU_CLBCNT_SHIFT);
 921         if (ret) {
 922                 dev_err(data->dev, "failed to set high delta coulomb counter\n");
 923                 goto disable_clk;
 924         }
 925
 926         /*
 927          * Get the boot battery capacity when system powers on, which is used to
 928          * initialize the coulomb counter. After that, we can read the coulomb
 929          * counter to measure the battery capacity.
 930          */
 931         ret = sc27xx_fgu_get_boot_capacity(data, &data->init_cap);
 932         if (ret) {
 933                 dev_err(data->dev, "failed to get boot capacity\n");
 934                 goto disable_clk;
 935         }
 936
 937         /*
 938          * Convert battery capacity to the corresponding initial coulomb counter
 939          * and set into coulomb counter registers.
 940          */
 941         data->init_clbcnt = sc27xx_fgu_cap_to_clbcnt(data, data->init_cap);
 942         ret = sc27xx_fgu_set_clbcnt(data, data->init_clbcnt);
 943         if (ret) {
 944                 dev_err(data->dev, "failed to initialize coulomb counter\n");
 945                 goto disable_clk;
 946         }
 947
 948         return 0;
 949
 950 disable_clk:
 951         regmap_update_bits(data->regmap, SC27XX_CLK_EN0, SC27XX_FGU_RTC_EN, 0);
 952 disable_fgu:
 953         regmap_update_bits(data->regmap, SC27XX_MODULE_EN0, SC27XX_FGU_EN, 0);
 954
 955         return ret;
 956 }
 957
 958 static int sc27xx_fgu_probe(struct platform_device *pdev)
 959 {
 960         struct device_node *np = pdev->dev.of_node;
 961         struct power_supply_config fgu_cfg = { };
 962         struct sc27xx_fgu_data *data;
 963         int ret, irq;
 964
 965         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 966         if (!data)
 967                 return -ENOMEM;
 968
 969         data->regmap = dev_get_regmap(pdev->dev.parent, NULL);
 970         if (!data->regmap) {
 971                 dev_err(&pdev->dev, "failed to get regmap\n");
 972                 return -ENODEV;
 973         }
 974
 975         ret = device_property_read_u32(&pdev->dev, "reg", &data->base);
 976         if (ret) {
 977                 dev_err(&pdev->dev, "failed to get fgu address\n");
 978                 return ret;
 979         }
 980
 981         data->channel = devm_iio_channel_get(&pdev->dev, "bat-temp");
 982         if (IS_ERR(data->channel)) {
 983                 dev_err(&pdev->dev, "failed to get IIO channel\n");
 984                 return PTR_ERR(data->channel);
 985         }
 986
 987         data->charge_chan = devm_iio_channel_get(&pdev->dev, "charge-vol");
 988         if (IS_ERR(data->charge_chan)) {
 989                 dev_err(&pdev->dev, "failed to get charge IIO channel\n");
 990                 return PTR_ERR(data->charge_chan);
 991         }
 992
 993         data->gpiod = devm_gpiod_get(&pdev->dev, "bat-detect", GPIOD_IN);
 994         if (IS_ERR(data->gpiod)) {
 995                 dev_err(&pdev->dev, "failed to get battery detection GPIO\n");
 996                 return PTR_ERR(data->gpiod);
 997         }
 998
 999         ret = gpiod_get_value_cansleep(data->gpiod);
1000         if (ret < 0) {
1001                 dev_err(&pdev->dev, "failed to get gpio state\n");
1002                 return ret;
1003         }
1004
1005         data->bat_present = !!ret;
1006         mutex_init(&data->lock);
1007         data->dev = &pdev->dev;
1008         platform_set_drvdata(pdev, data);
1009
1010         fgu_cfg.drv_data = data;
1011         fgu_cfg.of_node = np;
1012         data->battery = devm_power_supply_register(&pdev->dev, &sc27xx_fgu_desc,
1013                                                    &fgu_cfg);
1014         if (IS_ERR(data->battery)) {
1015                 dev_err(&pdev->dev, "failed to register power supply\n");
1016                 return PTR_ERR(data->battery);
1017         }
1018
1019         ret = sc27xx_fgu_hw_init(data);
1020         if (ret) {
1021                 dev_err(&pdev->dev, "failed to initialize fgu hardware\n");
1022                 return ret;
1023         }
1024
1025         ret = devm_add_action(&pdev->dev, sc27xx_fgu_disable, data);
1026         if (ret) {
1027                 sc27xx_fgu_disable(data);
1028                 dev_err(&pdev->dev, "failed to add fgu disable action\n");
1029                 return ret;
1030         }
1031
1032         irq = platform_get_irq(pdev, 0);
1033         if (irq < 0) {
1034                 dev_err(&pdev->dev, "no irq resource specified\n");
1035                 return irq;
1036         }
1037
1038         ret = devm_request_threaded_irq(data->dev, irq, NULL,
1039                                         sc27xx_fgu_interrupt,
1040                                         IRQF_NO_SUSPEND | IRQF_ONESHOT,
1041                                         pdev->name, data);
1042         if (ret) {
1043                 dev_err(data->dev, "failed to request fgu IRQ\n");
1044                 return ret;
1045         }
1046
1047         irq = gpiod_to_irq(data->gpiod);
1048         if (irq < 0) {
1049                 dev_err(&pdev->dev, "failed to translate GPIO to IRQ\n");
1050                 return irq;
1051         }
1052
1053         ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
1054                                         sc27xx_fgu_bat_detection,
1055                                         IRQF_ONESHOT | IRQF_TRIGGER_RISING |
1056                                         IRQF_TRIGGER_FALLING,
1057                                         pdev->name, data);
1058         if (ret) {
1059                 dev_err(&pdev->dev, "failed to request IRQ\n");
1060                 return ret;
1061         }
1062
1063         return 0;
1064 }
1065
1066 #ifdef CONFIG_PM_SLEEP
1067 static int sc27xx_fgu_resume(struct device *dev)
1068 {
1069         struct sc27xx_fgu_data *data = dev_get_drvdata(dev);
1070         int ret;
1071
1072         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1073                                  SC27XX_FGU_LOW_OVERLOAD_INT |
1074                                  SC27XX_FGU_CLBCNT_DELTA_INT, 0);
1075         if (ret) {
1076                 dev_err(data->dev, "failed to disable fgu interrupts\n");
1077                 return ret;
1078         }
1079
1080         return 0;
1081 }
1082
1083 static int sc27xx_fgu_suspend(struct device *dev)
1084 {
1085         struct sc27xx_fgu_data *data = dev_get_drvdata(dev);
1086         int ret, status, ocv;
1087
1088         ret = sc27xx_fgu_get_status(data, &status);
1089         if (ret)
1090                 return ret;
1091
1092         /*
1093          * If we are charging, then no need to enable the FGU interrupts to
1094          * adjust the battery capacity.
1095          */
1096         if (status != POWER_SUPPLY_STATUS_NOT_CHARGING)
1097                 return 0;
1098
1099         ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1100                                  SC27XX_FGU_LOW_OVERLOAD_INT,
1101                                  SC27XX_FGU_LOW_OVERLOAD_INT);
1102         if (ret) {
1103                 dev_err(data->dev, "failed to enable low voltage interrupt\n");
1104                 return ret;
1105         }
1106
1107         ret = sc27xx_fgu_get_vbat_ocv(data, &ocv);
1108         if (ret)
1109                 goto disable_int;
1110
1111         /*
1112          * If current OCV is less than the minimum voltage, we should enable the
1113          * coulomb counter threshold interrupt to notify events to adjust the
1114          * battery capacity.
1115          */
1116         if (ocv < data->min_volt) {
1117                 ret = regmap_update_bits(data->regmap,
1118                                          data->base + SC27XX_FGU_INT_EN,
1119                                          SC27XX_FGU_CLBCNT_DELTA_INT,
1120                                          SC27XX_FGU_CLBCNT_DELTA_INT);
1121                 if (ret) {
1122                         dev_err(data->dev,
1123                                 "failed to enable coulomb threshold int\n");
1124                         goto disable_int;
1125                 }
1126         }
1127
1128         return 0;
1129
1130 disable_int:
1131         regmap_update_bits(data->regmap, data->base + SC27XX_FGU_INT_EN,
1132                            SC27XX_FGU_LOW_OVERLOAD_INT, 0);
1133         return ret;
1134 }
1135 #endif
1136
1137 static const struct dev_pm_ops sc27xx_fgu_pm_ops = {
1138         SET_SYSTEM_SLEEP_PM_OPS(sc27xx_fgu_suspend, sc27xx_fgu_resume)
1139 };
1140
1141 static const struct of_device_id sc27xx_fgu_of_match[] = {
1142         { .compatible = "sprd,sc2731-fgu", },
1143         { }
1144 };
1145
1146 static struct platform_driver sc27xx_fgu_driver = {
1147         .probe = sc27xx_fgu_probe,
1148         .driver = {
1149                 .name = "sc27xx-fgu",
1150                 .of_match_table = sc27xx_fgu_of_match,
1151                 .pm = &sc27xx_fgu_pm_ops,
1152         }
1153 };
1154
1155 module_platform_driver(sc27xx_fgu_driver);
1156
1157 MODULE_DESCRIPTION("Spreadtrum SC27XX PMICs Fual Gauge Unit Driver");
1158 MODULE_LICENSE("GPL v2");