drivers/power/supply/sbs-battery.c

   1 /*
   2  * Gas Gauge driver for SBS Compliant Batteries
   3  *
   4  * Copyright (c) 2010, NVIDIA Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  */
  16
  17 #include <linux/delay.h>
  18 #include <linux/err.h>
  19 #include <linux/gpio/consumer.h>
  20 #include <linux/i2c.h>
  21 #include <linux/init.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/of.h>
  26 #include <linux/of_device.h>
  27 #include <linux/power/sbs-battery.h>
  28 #include <linux/power_supply.h>
  29 #include <linux/slab.h>
  30 #include <linux/stat.h>
  31
  32 enum {
  33         REG_MANUFACTURER_DATA,
  34         REG_TEMPERATURE,
  35         REG_VOLTAGE,
  36         REG_CURRENT,
  37         REG_CAPACITY,
  38         REG_TIME_TO_EMPTY,
  39         REG_TIME_TO_FULL,
  40         REG_STATUS,
  41         REG_CAPACITY_LEVEL,
  42         REG_CYCLE_COUNT,
  43         REG_SERIAL_NUMBER,
  44         REG_REMAINING_CAPACITY,
  45         REG_REMAINING_CAPACITY_CHARGE,
  46         REG_FULL_CHARGE_CAPACITY,
  47         REG_FULL_CHARGE_CAPACITY_CHARGE,
  48         REG_DESIGN_CAPACITY,
  49         REG_DESIGN_CAPACITY_CHARGE,
  50         REG_DESIGN_VOLTAGE_MIN,
  51         REG_DESIGN_VOLTAGE_MAX,
  52         REG_MANUFACTURER,
  53         REG_MODEL_NAME,
  54 };
  55
  56 /* Battery Mode defines */
  57 #define BATTERY_MODE_OFFSET             0x03
  58 #define BATTERY_MODE_MASK               0x8000
  59 enum sbs_battery_mode {
  60         BATTERY_MODE_AMPS = 0,
  61         BATTERY_MODE_WATTS = 0x8000
  62 };
  63
  64 /* manufacturer access defines */
  65 #define MANUFACTURER_ACCESS_STATUS      0x0006
  66 #define MANUFACTURER_ACCESS_SLEEP       0x0011
  67
  68 /* battery status value bits */
  69 #define BATTERY_INITIALIZED             0x80
  70 #define BATTERY_DISCHARGING             0x40
  71 #define BATTERY_FULL_CHARGED            0x20
  72 #define BATTERY_FULL_DISCHARGED         0x10
  73
  74 /* min_value and max_value are only valid for numerical data */
  75 #define SBS_DATA(_psp, _addr, _min_value, _max_value) { \
  76         .psp = _psp, \
  77         .addr = _addr, \
  78         .min_value = _min_value, \
  79         .max_value = _max_value, \
  80 }
  81
  82 static const struct chip_data {
  83         enum power_supply_property psp;
  84         u8 addr;
  85         int min_value;
  86         int max_value;
  87 } sbs_data[] = {
  88         [REG_MANUFACTURER_DATA] =
  89                 SBS_DATA(POWER_SUPPLY_PROP_PRESENT, 0x00, 0, 65535),
  90         [REG_TEMPERATURE] =
  91                 SBS_DATA(POWER_SUPPLY_PROP_TEMP, 0x08, 0, 65535),
  92         [REG_VOLTAGE] =
  93                 SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_NOW, 0x09, 0, 20000),
  94         [REG_CURRENT] =
  95                 SBS_DATA(POWER_SUPPLY_PROP_CURRENT_NOW, 0x0A, -32768, 32767),
  96         [REG_CAPACITY] =
  97                 SBS_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0D, 0, 100),
  98         [REG_REMAINING_CAPACITY] =
  99                 SBS_DATA(POWER_SUPPLY_PROP_ENERGY_NOW, 0x0F, 0, 65535),
 100         [REG_REMAINING_CAPACITY_CHARGE] =
 101                 SBS_DATA(POWER_SUPPLY_PROP_CHARGE_NOW, 0x0F, 0, 65535),
 102         [REG_FULL_CHARGE_CAPACITY] =
 103                 SBS_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
 104         [REG_FULL_CHARGE_CAPACITY_CHARGE] =
 105                 SBS_DATA(POWER_SUPPLY_PROP_CHARGE_FULL, 0x10, 0, 65535),
 106         [REG_TIME_TO_EMPTY] =
 107                 SBS_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0, 65535),
 108         [REG_TIME_TO_FULL] =
 109                 SBS_DATA(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, 0x13, 0, 65535),
 110         [REG_STATUS] =
 111                 SBS_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535),
 112         [REG_CAPACITY_LEVEL] =
 113                 SBS_DATA(POWER_SUPPLY_PROP_CAPACITY_LEVEL, 0x16, 0, 65535),
 114         [REG_CYCLE_COUNT] =
 115                 SBS_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535),
 116         [REG_DESIGN_CAPACITY] =
 117                 SBS_DATA(POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, 0x18, 0, 65535),
 118         [REG_DESIGN_CAPACITY_CHARGE] =
 119                 SBS_DATA(POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, 0x18, 0, 65535),
 120         [REG_DESIGN_VOLTAGE_MIN] =
 121                 SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, 0x19, 0, 65535),
 122         [REG_DESIGN_VOLTAGE_MAX] =
 123                 SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 0x19, 0, 65535),
 124         [REG_SERIAL_NUMBER] =
 125                 SBS_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535),
 126         /* Properties of type `const char *' */
 127         [REG_MANUFACTURER] =
 128                 SBS_DATA(POWER_SUPPLY_PROP_MANUFACTURER, 0x20, 0, 65535),
 129         [REG_MODEL_NAME] =
 130                 SBS_DATA(POWER_SUPPLY_PROP_MODEL_NAME, 0x21, 0, 65535)
 131 };
 132
 133 static enum power_supply_property sbs_properties[] = {
 134         POWER_SUPPLY_PROP_STATUS,
 135         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 136         POWER_SUPPLY_PROP_HEALTH,
 137         POWER_SUPPLY_PROP_PRESENT,
 138         POWER_SUPPLY_PROP_TECHNOLOGY,
 139         POWER_SUPPLY_PROP_CYCLE_COUNT,
 140         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 141         POWER_SUPPLY_PROP_CURRENT_NOW,
 142         POWER_SUPPLY_PROP_CAPACITY,
 143         POWER_SUPPLY_PROP_TEMP,
 144         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 145         POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
 146         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 147         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 148         POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
 149         POWER_SUPPLY_PROP_ENERGY_NOW,
 150         POWER_SUPPLY_PROP_ENERGY_FULL,
 151         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 152         POWER_SUPPLY_PROP_CHARGE_NOW,
 153         POWER_SUPPLY_PROP_CHARGE_FULL,
 154         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 155         /* Properties of type `const char *' */
 156         POWER_SUPPLY_PROP_MANUFACTURER,
 157         POWER_SUPPLY_PROP_MODEL_NAME
 158 };
 159
 160 /* Supports special manufacturer commands from TI BQ20Z75 IC. */
 161 #define SBS_FLAGS_TI_BQ20Z75            BIT(0)
 162
 163 struct sbs_info {
 164         struct i2c_client               *client;
 165         struct power_supply             *power_supply;
 166         bool                            is_present;
 167         struct gpio_desc                *gpio_detect;
 168         bool                            enable_detection;
 169         int                             last_state;
 170         int                             poll_time;
 171         u32                             i2c_retry_count;
 172         u32                             poll_retry_count;
 173         struct delayed_work             work;
 174         struct mutex                    mode_lock;
 175         u32                             flags;
 176 };
 177
 178 static char model_name[I2C_SMBUS_BLOCK_MAX + 1];
 179 static char manufacturer[I2C_SMBUS_BLOCK_MAX + 1];
 180 static bool force_load;
 181
 182 static int sbs_read_word_data(struct i2c_client *client, u8 address)
 183 {
 184         struct sbs_info *chip = i2c_get_clientdata(client);
 185         int retries = chip->i2c_retry_count;
 186         s32 ret = 0;
 187
 188         while (retries > 0) {
 189                 ret = i2c_smbus_read_word_data(client, address);
 190                 if (ret >= 0)
 191                         break;
 192                 retries--;
 193         }
 194
 195         if (ret < 0) {
 196                 dev_dbg(&client->dev,
 197                         "%s: i2c read at address 0x%x failed\n",
 198                         __func__, address);
 199                 return ret;
 200         }
 201
 202         return ret;
 203 }
 204
 205 static int sbs_read_string_data(struct i2c_client *client, u8 address,
 206                                 char *values)
 207 {
 208         struct sbs_info *chip = i2c_get_clientdata(client);
 209         s32 ret = 0, block_length = 0;
 210         int retries_length, retries_block;
 211         u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
 212
 213         retries_length = chip->i2c_retry_count;
 214         retries_block = chip->i2c_retry_count;
 215
 216         /* Adapter needs to support these two functions */
 217         if (!i2c_check_functionality(client->adapter,
 218                                      I2C_FUNC_SMBUS_BYTE_DATA |
 219                                      I2C_FUNC_SMBUS_I2C_BLOCK)){
 220                 return -ENODEV;
 221         }
 222
 223         /* Get the length of block data */
 224         while (retries_length > 0) {
 225                 ret = i2c_smbus_read_byte_data(client, address);
 226                 if (ret >= 0)
 227                         break;
 228                 retries_length--;
 229         }
 230
 231         if (ret < 0) {
 232                 dev_dbg(&client->dev,
 233                         "%s: i2c read at address 0x%x failed\n",
 234                         __func__, address);
 235                 return ret;
 236         }
 237
 238         /* block_length does not include NULL terminator */
 239         block_length = ret;
 240         if (block_length > I2C_SMBUS_BLOCK_MAX) {
 241                 dev_err(&client->dev,
 242                         "%s: Returned block_length is longer than 0x%x\n",
 243                         __func__, I2C_SMBUS_BLOCK_MAX);
 244                 return -EINVAL;
 245         }
 246
 247         /* Get the block data */
 248         while (retries_block > 0) {
 249                 ret = i2c_smbus_read_i2c_block_data(
 250                                 client, address,
 251                                 block_length + 1, block_buffer);
 252                 if (ret >= 0)
 253                         break;
 254                 retries_block--;
 255         }
 256
 257         if (ret < 0) {
 258                 dev_dbg(&client->dev,
 259                         "%s: i2c read at address 0x%x failed\n",
 260                         __func__, address);
 261                 return ret;
 262         }
 263
 264         /* block_buffer[0] == block_length */
 265         memcpy(values, block_buffer + 1, block_length);
 266         values[block_length] = '\0';
 267
 268         return ret;
 269 }
 270
 271 static int sbs_write_word_data(struct i2c_client *client, u8 address,
 272         u16 value)
 273 {
 274         struct sbs_info *chip = i2c_get_clientdata(client);
 275         int retries = chip->i2c_retry_count;
 276         s32 ret = 0;
 277
 278         while (retries > 0) {
 279                 ret = i2c_smbus_write_word_data(client, address, value);
 280                 if (ret >= 0)
 281                         break;
 282                 retries--;
 283         }
 284
 285         if (ret < 0) {
 286                 dev_dbg(&client->dev,
 287                         "%s: i2c write to address 0x%x failed\n",
 288                         __func__, address);
 289                 return ret;
 290         }
 291
 292         return 0;
 293 }
 294
 295 static int sbs_status_correct(struct i2c_client *client, int *intval)
 296 {
 297         int ret;
 298
 299         ret = sbs_read_word_data(client, sbs_data[REG_CURRENT].addr);
 300         if (ret < 0)
 301                 return ret;
 302
 303         ret = (s16)ret;
 304
 305         /* Not drawing current means full (cannot be not charging) */
 306         if (ret == 0)
 307                 *intval = POWER_SUPPLY_STATUS_FULL;
 308
 309         if (*intval == POWER_SUPPLY_STATUS_FULL) {
 310                 /* Drawing or providing current when full */
 311                 if (ret > 0)
 312                         *intval = POWER_SUPPLY_STATUS_CHARGING;
 313                 else if (ret < 0)
 314                         *intval = POWER_SUPPLY_STATUS_DISCHARGING;
 315         }
 316
 317         return 0;
 318 }
 319
 320 static int sbs_get_battery_presence_and_health(
 321         struct i2c_client *client, enum power_supply_property psp,
 322         union power_supply_propval *val)
 323 {
 324         int ret;
 325
 326         /* Dummy command; if it succeeds, battery is present. */
 327         ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
 328
 329         if (ret < 0) { /* battery not present*/
 330                 if (psp == POWER_SUPPLY_PROP_PRESENT) {
 331                         val->intval = 0;
 332                         return 0;
 333                 }
 334                 return ret;
 335         }
 336
 337         if (psp == POWER_SUPPLY_PROP_PRESENT)
 338                 val->intval = 1; /* battery present */
 339         else /* POWER_SUPPLY_PROP_HEALTH */
 340                 /* SBS spec doesn't have a general health command. */
 341                 val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
 342
 343         return 0;
 344 }
 345
 346 static int sbs_get_ti_battery_presence_and_health(
 347         struct i2c_client *client, enum power_supply_property psp,
 348         union power_supply_propval *val)
 349 {
 350         s32 ret;
 351
 352         /*
 353          * Write to ManufacturerAccess with ManufacturerAccess command
 354          * and then read the status.
 355          */
 356         ret = sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
 357                                   MANUFACTURER_ACCESS_STATUS);
 358         if (ret < 0) {
 359                 if (psp == POWER_SUPPLY_PROP_PRESENT)
 360                         val->intval = 0; /* battery removed */
 361                 return ret;
 362         }
 363
 364         ret = sbs_read_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr);
 365         if (ret < 0) {
 366                 if (psp == POWER_SUPPLY_PROP_PRESENT)
 367                         val->intval = 0; /* battery removed */
 368                 return ret;
 369         }
 370
 371         if (ret < sbs_data[REG_MANUFACTURER_DATA].min_value ||
 372             ret > sbs_data[REG_MANUFACTURER_DATA].max_value) {
 373                 val->intval = 0;
 374                 return 0;
 375         }
 376
 377         /* Mask the upper nibble of 2nd byte and
 378          * lower byte of response then
 379          * shift the result by 8 to get status*/
 380         ret &= 0x0F00;
 381         ret >>= 8;
 382         if (psp == POWER_SUPPLY_PROP_PRESENT) {
 383                 if (ret == 0x0F)
 384                         /* battery removed */
 385                         val->intval = 0;
 386                 else
 387                         val->intval = 1;
 388         } else if (psp == POWER_SUPPLY_PROP_HEALTH) {
 389                 if (ret == 0x09)
 390                         val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
 391                 else if (ret == 0x0B)
 392                         val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
 393                 else if (ret == 0x0C)
 394                         val->intval = POWER_SUPPLY_HEALTH_DEAD;
 395                 else
 396                         val->intval = POWER_SUPPLY_HEALTH_GOOD;
 397         }
 398
 399         return 0;
 400 }
 401
 402 static int sbs_get_battery_property(struct i2c_client *client,
 403         int reg_offset, enum power_supply_property psp,
 404         union power_supply_propval *val)
 405 {
 406         struct sbs_info *chip = i2c_get_clientdata(client);
 407         s32 ret;
 408
 409         ret = sbs_read_word_data(client, sbs_data[reg_offset].addr);
 410         if (ret < 0)
 411                 return ret;
 412
 413         /* returned values are 16 bit */
 414         if (sbs_data[reg_offset].min_value < 0)
 415                 ret = (s16)ret;
 416
 417         if (ret >= sbs_data[reg_offset].min_value &&
 418             ret <= sbs_data[reg_offset].max_value) {
 419                 val->intval = ret;
 420                 if (psp == POWER_SUPPLY_PROP_CAPACITY_LEVEL) {
 421                         if (!(ret & BATTERY_INITIALIZED))
 422                                 val->intval =
 423                                         POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
 424                         else if (ret & BATTERY_FULL_CHARGED)
 425                                 val->intval =
 426                                         POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 427                         else if (ret & BATTERY_FULL_DISCHARGED)
 428                                 val->intval =
 429                                         POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 430                         else
 431                                 val->intval =
 432                                         POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 433                         return 0;
 434                 } else if (psp != POWER_SUPPLY_PROP_STATUS) {
 435                         return 0;
 436                 }
 437
 438                 if (ret & BATTERY_FULL_CHARGED)
 439                         val->intval = POWER_SUPPLY_STATUS_FULL;
 440                 else if (ret & BATTERY_DISCHARGING)
 441                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 442                 else
 443                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 444
 445                 sbs_status_correct(client, &val->intval);
 446
 447                 if (chip->poll_time == 0)
 448                         chip->last_state = val->intval;
 449                 else if (chip->last_state != val->intval) {
 450                         cancel_delayed_work_sync(&chip->work);
 451                         power_supply_changed(chip->power_supply);
 452                         chip->poll_time = 0;
 453                 }
 454         } else {
 455                 if (psp == POWER_SUPPLY_PROP_STATUS)
 456                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 457                 else if (psp == POWER_SUPPLY_PROP_CAPACITY)
 458                         /* sbs spec says that this can be >100 %
 459                          * even if max value is 100 %
 460                          */
 461                         val->intval = min(ret, 100);
 462                 else
 463                         val->intval = 0;
 464         }
 465
 466         return 0;
 467 }
 468
 469 static int sbs_get_battery_string_property(struct i2c_client *client,
 470         int reg_offset, enum power_supply_property psp, char *val)
 471 {
 472         s32 ret;
 473
 474         ret = sbs_read_string_data(client, sbs_data[reg_offset].addr, val);
 475
 476         if (ret < 0)
 477                 return ret;
 478
 479         return 0;
 480 }
 481
 482 static void  sbs_unit_adjustment(struct i2c_client *client,
 483         enum power_supply_property psp, union power_supply_propval *val)
 484 {
 485 #define BASE_UNIT_CONVERSION            1000
 486 #define BATTERY_MODE_CAP_MULT_WATT      (10 * BASE_UNIT_CONVERSION)
 487 #define TIME_UNIT_CONVERSION            60
 488 #define TEMP_KELVIN_TO_CELSIUS          2731
 489         switch (psp) {
 490         case POWER_SUPPLY_PROP_ENERGY_NOW:
 491         case POWER_SUPPLY_PROP_ENERGY_FULL:
 492         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 493                 /* sbs provides energy in units of 10mWh.
 494                  * Convert to µWh
 495                  */
 496                 val->intval *= BATTERY_MODE_CAP_MULT_WATT;
 497                 break;
 498
 499         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 500         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 501         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 502         case POWER_SUPPLY_PROP_CURRENT_NOW:
 503         case POWER_SUPPLY_PROP_CHARGE_NOW:
 504         case POWER_SUPPLY_PROP_CHARGE_FULL:
 505         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 506                 val->intval *= BASE_UNIT_CONVERSION;
 507                 break;
 508
 509         case POWER_SUPPLY_PROP_TEMP:
 510                 /* sbs provides battery temperature in 0.1K
 511                  * so convert it to 0.1°C
 512                  */
 513                 val->intval -= TEMP_KELVIN_TO_CELSIUS;
 514                 break;
 515
 516         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 517         case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
 518                 /* sbs provides time to empty and time to full in minutes.
 519                  * Convert to seconds
 520                  */
 521                 val->intval *= TIME_UNIT_CONVERSION;
 522                 break;
 523
 524         default:
 525                 dev_dbg(&client->dev,
 526                         "%s: no need for unit conversion %d\n", __func__, psp);
 527         }
 528 }
 529
 530 static enum sbs_battery_mode sbs_set_battery_mode(struct i2c_client *client,
 531         enum sbs_battery_mode mode)
 532 {
 533         int ret, original_val;
 534
 535         original_val = sbs_read_word_data(client, BATTERY_MODE_OFFSET);
 536         if (original_val < 0)
 537                 return original_val;
 538
 539         if ((original_val & BATTERY_MODE_MASK) == mode)
 540                 return mode;
 541
 542         if (mode == BATTERY_MODE_AMPS)
 543                 ret = original_val & ~BATTERY_MODE_MASK;
 544         else
 545                 ret = original_val | BATTERY_MODE_MASK;
 546
 547         ret = sbs_write_word_data(client, BATTERY_MODE_OFFSET, ret);
 548         if (ret < 0)
 549                 return ret;
 550
 551         usleep_range(1000, 2000);
 552
 553         return original_val & BATTERY_MODE_MASK;
 554 }
 555
 556 static int sbs_get_battery_capacity(struct i2c_client *client,
 557         int reg_offset, enum power_supply_property psp,
 558         union power_supply_propval *val)
 559 {
 560         s32 ret;
 561         enum sbs_battery_mode mode = BATTERY_MODE_WATTS;
 562
 563         if (power_supply_is_amp_property(psp))
 564                 mode = BATTERY_MODE_AMPS;
 565
 566         mode = sbs_set_battery_mode(client, mode);
 567         if (mode < 0)
 568                 return mode;
 569
 570         ret = sbs_read_word_data(client, sbs_data[reg_offset].addr);
 571         if (ret < 0)
 572                 return ret;
 573
 574         val->intval = ret;
 575
 576         ret = sbs_set_battery_mode(client, mode);
 577         if (ret < 0)
 578                 return ret;
 579
 580         return 0;
 581 }
 582
 583 static char sbs_serial[5];
 584 static int sbs_get_battery_serial_number(struct i2c_client *client,
 585         union power_supply_propval *val)
 586 {
 587         int ret;
 588
 589         ret = sbs_read_word_data(client, sbs_data[REG_SERIAL_NUMBER].addr);
 590         if (ret < 0)
 591                 return ret;
 592
 593         sprintf(sbs_serial, "%04x", ret);
 594         val->strval = sbs_serial;
 595
 596         return 0;
 597 }
 598
 599 static int sbs_get_property_index(struct i2c_client *client,
 600         enum power_supply_property psp)
 601 {
 602         int count;
 603         for (count = 0; count < ARRAY_SIZE(sbs_data); count++)
 604                 if (psp == sbs_data[count].psp)
 605                         return count;
 606
 607         dev_warn(&client->dev,
 608                 "%s: Invalid Property - %d\n", __func__, psp);
 609
 610         return -EINVAL;
 611 }
 612
 613 static int sbs_get_property(struct power_supply *psy,
 614         enum power_supply_property psp,
 615         union power_supply_propval *val)
 616 {
 617         int ret = 0;
 618         struct sbs_info *chip = power_supply_get_drvdata(psy);
 619         struct i2c_client *client = chip->client;
 620
 621         if (chip->gpio_detect) {
 622                 ret = gpiod_get_value_cansleep(chip->gpio_detect);
 623                 if (ret < 0)
 624                         return ret;
 625                 if (psp == POWER_SUPPLY_PROP_PRESENT) {
 626                         val->intval = ret;
 627                         chip->is_present = val->intval;
 628                         return 0;
 629                 }
 630                 if (ret == 0)
 631                         return -ENODATA;
 632         }
 633
 634         switch (psp) {
 635         case POWER_SUPPLY_PROP_PRESENT:
 636         case POWER_SUPPLY_PROP_HEALTH:
 637                 if (chip->flags & SBS_FLAGS_TI_BQ20Z75)
 638                         ret = sbs_get_ti_battery_presence_and_health(client,
 639                                                                      psp, val);
 640                 else
 641                         ret = sbs_get_battery_presence_and_health(client, psp,
 642                                                                   val);
 643
 644                 /* this can only be true if no gpio is used */
 645                 if (psp == POWER_SUPPLY_PROP_PRESENT)
 646                         return 0;
 647                 break;
 648
 649         case POWER_SUPPLY_PROP_TECHNOLOGY:
 650                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 651                 goto done; /* don't trigger power_supply_changed()! */
 652
 653         case POWER_SUPPLY_PROP_ENERGY_NOW:
 654         case POWER_SUPPLY_PROP_ENERGY_FULL:
 655         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 656         case POWER_SUPPLY_PROP_CHARGE_NOW:
 657         case POWER_SUPPLY_PROP_CHARGE_FULL:
 658         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 659                 ret = sbs_get_property_index(client, psp);
 660                 if (ret < 0)
 661                         break;
 662
 663                 /* sbs_get_battery_capacity() will change the battery mode
 664                  * temporarily to read the requested attribute. Ensure we stay
 665                  * in the desired mode for the duration of the attribute read.
 666                  */
 667                 mutex_lock(&chip->mode_lock);
 668                 ret = sbs_get_battery_capacity(client, ret, psp, val);
 669                 mutex_unlock(&chip->mode_lock);
 670                 break;
 671
 672         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 673                 ret = sbs_get_battery_serial_number(client, val);
 674                 break;
 675
 676         case POWER_SUPPLY_PROP_STATUS:
 677         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 678         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 679         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 680         case POWER_SUPPLY_PROP_CURRENT_NOW:
 681         case POWER_SUPPLY_PROP_TEMP:
 682         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 683         case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
 684         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 685         case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 686         case POWER_SUPPLY_PROP_CAPACITY:
 687                 ret = sbs_get_property_index(client, psp);
 688                 if (ret < 0)
 689                         break;
 690
 691                 ret = sbs_get_battery_property(client, ret, psp, val);
 692                 break;
 693
 694         case POWER_SUPPLY_PROP_MODEL_NAME:
 695                 ret = sbs_get_property_index(client, psp);
 696                 if (ret < 0)
 697                         break;
 698
 699                 ret = sbs_get_battery_string_property(client, ret, psp,
 700                                                       model_name);
 701                 val->strval = model_name;
 702                 break;
 703
 704         case POWER_SUPPLY_PROP_MANUFACTURER:
 705                 ret = sbs_get_property_index(client, psp);
 706                 if (ret < 0)
 707                         break;
 708
 709                 ret = sbs_get_battery_string_property(client, ret, psp,
 710                                                       manufacturer);
 711                 val->strval = manufacturer;
 712                 break;
 713
 714         default:
 715                 dev_err(&client->dev,
 716                         "%s: INVALID property\n", __func__);
 717                 return -EINVAL;
 718         }
 719
 720         if (!chip->enable_detection)
 721                 goto done;
 722
 723         if (!chip->gpio_detect &&
 724                 chip->is_present != (ret >= 0)) {
 725                 chip->is_present = (ret >= 0);
 726                 power_supply_changed(chip->power_supply);
 727         }
 728
 729 done:
 730         if (!ret) {
 731                 /* Convert units to match requirements for power supply class */
 732                 sbs_unit_adjustment(client, psp, val);
 733         }
 734
 735         dev_dbg(&client->dev,
 736                 "%s: property = %d, value = %x\n", __func__, psp, val->intval);
 737
 738         if (ret && chip->is_present)
 739                 return ret;
 740
 741         /* battery not present, so return NODATA for properties */
 742         if (ret)
 743                 return -ENODATA;
 744
 745         return 0;
 746 }
 747
 748 static void sbs_supply_changed(struct sbs_info *chip)
 749 {
 750         struct power_supply *battery = chip->power_supply;
 751         int ret;
 752
 753         ret = gpiod_get_value_cansleep(chip->gpio_detect);
 754         if (ret < 0)
 755                 return;
 756         chip->is_present = ret;
 757         power_supply_changed(battery);
 758 }
 759
 760 static irqreturn_t sbs_irq(int irq, void *devid)
 761 {
 762         sbs_supply_changed(devid);
 763         return IRQ_HANDLED;
 764 }
 765
 766 static void sbs_alert(struct i2c_client *client, enum i2c_alert_protocol prot,
 767         unsigned int data)
 768 {
 769         sbs_supply_changed(i2c_get_clientdata(client));
 770 }
 771
 772 static void sbs_external_power_changed(struct power_supply *psy)
 773 {
 774         struct sbs_info *chip = power_supply_get_drvdata(psy);
 775
 776         /* cancel outstanding work */
 777         cancel_delayed_work_sync(&chip->work);
 778
 779         schedule_delayed_work(&chip->work, HZ);
 780         chip->poll_time = chip->poll_retry_count;
 781 }
 782
 783 static void sbs_delayed_work(struct work_struct *work)
 784 {
 785         struct sbs_info *chip;
 786         s32 ret;
 787
 788         chip = container_of(work, struct sbs_info, work.work);
 789
 790         ret = sbs_read_word_data(chip->client, sbs_data[REG_STATUS].addr);
 791         /* if the read failed, give up on this work */
 792         if (ret < 0) {
 793                 chip->poll_time = 0;
 794                 return;
 795         }
 796
 797         if (ret & BATTERY_FULL_CHARGED)
 798                 ret = POWER_SUPPLY_STATUS_FULL;
 799         else if (ret & BATTERY_DISCHARGING)
 800                 ret = POWER_SUPPLY_STATUS_DISCHARGING;
 801         else
 802                 ret = POWER_SUPPLY_STATUS_CHARGING;
 803
 804         sbs_status_correct(chip->client, &ret);
 805
 806         if (chip->last_state != ret) {
 807                 chip->poll_time = 0;
 808                 power_supply_changed(chip->power_supply);
 809                 return;
 810         }
 811         if (chip->poll_time > 0) {
 812                 schedule_delayed_work(&chip->work, HZ);
 813                 chip->poll_time--;
 814                 return;
 815         }
 816 }
 817
 818 static const struct power_supply_desc sbs_default_desc = {
 819         .type = POWER_SUPPLY_TYPE_BATTERY,
 820         .properties = sbs_properties,
 821         .num_properties = ARRAY_SIZE(sbs_properties),
 822         .get_property = sbs_get_property,
 823         .external_power_changed = sbs_external_power_changed,
 824 };
 825
 826 static int sbs_probe(struct i2c_client *client,
 827         const struct i2c_device_id *id)
 828 {
 829         struct sbs_info *chip;
 830         struct power_supply_desc *sbs_desc;
 831         struct sbs_platform_data *pdata = client->dev.platform_data;
 832         struct power_supply_config psy_cfg = {};
 833         int rc;
 834         int irq;
 835
 836         sbs_desc = devm_kmemdup(&client->dev, &sbs_default_desc,
 837                         sizeof(*sbs_desc), GFP_KERNEL);
 838         if (!sbs_desc)
 839                 return -ENOMEM;
 840
 841         sbs_desc->name = devm_kasprintf(&client->dev, GFP_KERNEL, "sbs-%s",
 842                         dev_name(&client->dev));
 843         if (!sbs_desc->name)
 844                 return -ENOMEM;
 845
 846         chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
 847         if (!chip)
 848                 return -ENOMEM;
 849
 850         chip->flags = (u32)(uintptr_t)of_device_get_match_data(&client->dev);
 851         chip->client = client;
 852         chip->enable_detection = false;
 853         psy_cfg.of_node = client->dev.of_node;
 854         psy_cfg.drv_data = chip;
 855         chip->last_state = POWER_SUPPLY_STATUS_UNKNOWN;
 856         mutex_init(&chip->mode_lock);
 857
 858         /* use pdata if available, fall back to DT properties,
 859          * or hardcoded defaults if not
 860          */
 861         rc = of_property_read_u32(client->dev.of_node, "sbs,i2c-retry-count",
 862                                   &chip->i2c_retry_count);
 863         if (rc)
 864                 chip->i2c_retry_count = 0;
 865
 866         rc = of_property_read_u32(client->dev.of_node, "sbs,poll-retry-count",
 867                                   &chip->poll_retry_count);
 868         if (rc)
 869                 chip->poll_retry_count = 0;
 870
 871         if (pdata) {
 872                 chip->poll_retry_count = pdata->poll_retry_count;
 873                 chip->i2c_retry_count  = pdata->i2c_retry_count;
 874         }
 875         chip->i2c_retry_count = chip->i2c_retry_count + 1;
 876
 877         chip->gpio_detect = devm_gpiod_get_optional(&client->dev,
 878                         "sbs,battery-detect", GPIOD_IN);
 879         if (IS_ERR(chip->gpio_detect)) {
 880                 dev_err(&client->dev, "Failed to get gpio: %ld\n",
 881                         PTR_ERR(chip->gpio_detect));
 882                 return PTR_ERR(chip->gpio_detect);
 883         }
 884
 885         i2c_set_clientdata(client, chip);
 886
 887         if (!chip->gpio_detect)
 888                 goto skip_gpio;
 889
 890         irq = gpiod_to_irq(chip->gpio_detect);
 891         if (irq <= 0) {
 892                 dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq);
 893                 goto skip_gpio;
 894         }
 895
 896         rc = devm_request_threaded_irq(&client->dev, irq, NULL, sbs_irq,
 897                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 898                 dev_name(&client->dev), chip);
 899         if (rc) {
 900                 dev_warn(&client->dev, "Failed to request irq: %d\n", rc);
 901                 goto skip_gpio;
 902         }
 903
 904 skip_gpio:
 905         /*
 906          * Before we register, we might need to make sure we can actually talk
 907          * to the battery.
 908          */
 909         if (!(force_load || chip->gpio_detect)) {
 910                 rc = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
 911
 912                 if (rc < 0) {
 913                         dev_err(&client->dev, "%s: Failed to get device status\n",
 914                                 __func__);
 915                         goto exit_psupply;
 916                 }
 917         }
 918
 919         chip->power_supply = devm_power_supply_register(&client->dev, sbs_desc,
 920                                                    &psy_cfg);
 921         if (IS_ERR(chip->power_supply)) {
 922                 dev_err(&client->dev,
 923                         "%s: Failed to register power supply\n", __func__);
 924                 rc = PTR_ERR(chip->power_supply);
 925                 goto exit_psupply;
 926         }
 927
 928         dev_info(&client->dev,
 929                 "%s: battery gas gauge device registered\n", client->name);
 930
 931         INIT_DELAYED_WORK(&chip->work, sbs_delayed_work);
 932
 933         chip->enable_detection = true;
 934
 935         return 0;
 936
 937 exit_psupply:
 938         return rc;
 939 }
 940
 941 static int sbs_remove(struct i2c_client *client)
 942 {
 943         struct sbs_info *chip = i2c_get_clientdata(client);
 944
 945         cancel_delayed_work_sync(&chip->work);
 946
 947         return 0;
 948 }
 949
 950 #if defined CONFIG_PM_SLEEP
 951
 952 static int sbs_suspend(struct device *dev)
 953 {
 954         struct i2c_client *client = to_i2c_client(dev);
 955         struct sbs_info *chip = i2c_get_clientdata(client);
 956         int ret;
 957
 958         if (chip->poll_time > 0)
 959                 cancel_delayed_work_sync(&chip->work);
 960
 961         if (chip->flags & SBS_FLAGS_TI_BQ20Z75) {
 962                 /* Write to manufacturer access with sleep command. */
 963                 ret = sbs_write_word_data(client,
 964                                           sbs_data[REG_MANUFACTURER_DATA].addr,
 965                                           MANUFACTURER_ACCESS_SLEEP);
 966                 if (chip->is_present && ret < 0)
 967                         return ret;
 968         }
 969
 970         return 0;
 971 }
 972
 973 static SIMPLE_DEV_PM_OPS(sbs_pm_ops, sbs_suspend, NULL);
 974 #define SBS_PM_OPS (&sbs_pm_ops)
 975
 976 #else
 977 #define SBS_PM_OPS NULL
 978 #endif
 979
 980 static const struct i2c_device_id sbs_id[] = {
 981         { "bq20z75", 0 },
 982         { "sbs-battery", 1 },
 983         {}
 984 };
 985 MODULE_DEVICE_TABLE(i2c, sbs_id);
 986
 987 static const struct of_device_id sbs_dt_ids[] = {
 988         { .compatible = "sbs,sbs-battery" },
 989         {
 990                 .compatible = "ti,bq20z75",
 991                 .data = (void *)SBS_FLAGS_TI_BQ20Z75,
 992         },
 993         { }
 994 };
 995 MODULE_DEVICE_TABLE(of, sbs_dt_ids);
 996
 997 static struct i2c_driver sbs_battery_driver = {
 998         .probe          = sbs_probe,
 999         .remove         = sbs_remove,
1000         .alert          = sbs_alert,
1001         .id_table       = sbs_id,
1002         .driver = {
1003                 .name   = "sbs-battery",
1004                 .of_match_table = sbs_dt_ids,
1005                 .pm     = SBS_PM_OPS,
1006         },
1007 };
1008 module_i2c_driver(sbs_battery_driver);
1009
1010 MODULE_DESCRIPTION("SBS battery monitor driver");
1011 MODULE_LICENSE("GPL");
1012
1013 module_param(force_load, bool, S_IRUSR | S_IRGRP | S_IROTH);
1014 MODULE_PARM_DESC(force_load,
1015                  "Attempt to load the driver even if no battery is connected");