drivers/power/bq27xxx_battery.c

   1 /*
   2  * BQ27xxx battery driver
   3  *
   4  * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
   5  * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
   6  * Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
   7  * Copyright (C) 2011 Pali Rohár <pali.rohar@gmail.com>
   8  *
   9  * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
  10  *
  11  * This package is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  *
  15  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  17  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  18  *
  19  * Datasheets:
  20  * http://focus.ti.com/docs/prod/folders/print/bq27000.html
  21  * http://focus.ti.com/docs/prod/folders/print/bq27500.html
  22  * http://www.ti.com/product/bq27425-g1
  23  * http://www.ti.com/product/BQ27742-G1
  24  * http://www.ti.com/product/BQ27510-G3
  25  */
  26
  27 #include <linux/device.h>
  28 #include <linux/module.h>
  29 #include <linux/param.h>
  30 #include <linux/jiffies.h>
  31 #include <linux/workqueue.h>
  32 #include <linux/delay.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/power_supply.h>
  35 #include <linux/idr.h>
  36 #include <linux/i2c.h>
  37 #include <linux/slab.h>
  38 #include <asm/unaligned.h>
  39
  40 #include <linux/power/bq27xxx_battery.h>
  41
  42 #define DRIVER_VERSION          "1.2.0"
  43
  44 #define BQ27XXX_MANUFACTURER    "Texas Instruments"
  45
  46 #define BQ27x00_REG_TEMP        0x06
  47 #define BQ27x00_REG_VOLT        0x08
  48 #define BQ27x00_REG_AI          0x14
  49 #define BQ27x00_REG_FLAGS       0x0A
  50 #define BQ27x00_REG_TTE         0x16
  51 #define BQ27x00_REG_TTF         0x18
  52 #define BQ27x00_REG_TTECP       0x26
  53 #define BQ27x00_REG_NAC         0x0C /* Nominal available capacity */
  54 #define BQ27x00_REG_LMD         0x12 /* Last measured discharge */
  55 #define BQ27x00_REG_CYCT        0x2A /* Cycle count total */
  56 #define BQ27x00_REG_AE          0x22 /* Available energy */
  57 #define BQ27x00_POWER_AVG       0x24
  58
  59 #define BQ27000_REG_RSOC        0x0B /* Relative State-of-Charge */
  60 #define BQ27000_REG_ILMD        0x76 /* Initial last measured discharge */
  61 #define BQ27000_FLAG_EDVF       BIT(0) /* Final End-of-Discharge-Voltage flag */
  62 #define BQ27000_FLAG_EDV1       BIT(1) /* First End-of-Discharge-Voltage flag */
  63 #define BQ27000_FLAG_CI         BIT(4) /* Capacity Inaccurate flag */
  64 #define BQ27000_FLAG_FC         BIT(5)
  65 #define BQ27000_FLAG_CHGS       BIT(7) /* Charge state flag */
  66
  67 #define BQ27500_REG_SOC         0x2C
  68 #define BQ27500_REG_DCAP        0x3C /* Design capacity */
  69 #define BQ27500_FLAG_DSC        BIT(0)
  70 #define BQ27500_FLAG_SOCF       BIT(1) /* State-of-Charge threshold final */
  71 #define BQ27500_FLAG_SOC1       BIT(2) /* State-of-Charge threshold 1 */
  72 #define BQ27500_FLAG_FC         BIT(9)
  73 #define BQ27500_FLAG_OTC        BIT(15)
  74
  75 #define BQ27742_POWER_AVG       0x76
  76
  77 #define BQ27510_REG_SOC         0x20
  78 #define BQ27510_REG_DCAP        0x2E /* Design capacity */
  79 #define BQ27510_REG_CYCT        0x1E /* Cycle count total */
  80
  81 /* bq27425 register addresses are same as bq27x00 addresses minus 4 */
  82 #define BQ27425_REG_OFFSET      0x04
  83 #define BQ27425_REG_SOC         (0x1C + BQ27425_REG_OFFSET)
  84 #define BQ27425_REG_DCAP        (0x3C + BQ27425_REG_OFFSET)
  85
  86 #define BQ27XXX_RS                      20 /* Resistor sense */
  87 #define BQ27XXX_POWER_CONSTANT          (256 * 29200 / 1000)
  88
  89 struct bq27xxx_device_info;
  90 struct bq27xxx_access_methods {
  91         int (*read)(struct bq27xxx_device_info *di, u8 reg, bool single);
  92 };
  93
  94 struct bq27xxx_reg_cache {
  95         int temperature;
  96         int time_to_empty;
  97         int time_to_empty_avg;
  98         int time_to_full;
  99         int charge_full;
 100         int cycle_count;
 101         int capacity;
 102         int energy;
 103         int flags;
 104         int power_avg;
 105         int health;
 106 };
 107
 108 struct bq27xxx_device_info {
 109         struct device           *dev;
 110         int                     id;
 111         enum bq27xxx_chip       chip;
 112
 113         struct bq27xxx_reg_cache cache;
 114         int charge_design_full;
 115
 116         unsigned long last_update;
 117         struct delayed_work work;
 118
 119         struct power_supply     *bat;
 120
 121         struct bq27xxx_access_methods bus;
 122
 123         struct mutex lock;
 124 };
 125
 126 static enum power_supply_property bq27x00_battery_props[] = {
 127         POWER_SUPPLY_PROP_STATUS,
 128         POWER_SUPPLY_PROP_PRESENT,
 129         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 130         POWER_SUPPLY_PROP_CURRENT_NOW,
 131         POWER_SUPPLY_PROP_CAPACITY,
 132         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 133         POWER_SUPPLY_PROP_TEMP,
 134         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 135         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 136         POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 137         POWER_SUPPLY_PROP_TECHNOLOGY,
 138         POWER_SUPPLY_PROP_CHARGE_FULL,
 139         POWER_SUPPLY_PROP_CHARGE_NOW,
 140         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 141         POWER_SUPPLY_PROP_CYCLE_COUNT,
 142         POWER_SUPPLY_PROP_ENERGY_NOW,
 143         POWER_SUPPLY_PROP_POWER_AVG,
 144         POWER_SUPPLY_PROP_HEALTH,
 145         POWER_SUPPLY_PROP_MANUFACTURER,
 146 };
 147
 148 static enum power_supply_property bq27425_battery_props[] = {
 149         POWER_SUPPLY_PROP_STATUS,
 150         POWER_SUPPLY_PROP_PRESENT,
 151         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 152         POWER_SUPPLY_PROP_CURRENT_NOW,
 153         POWER_SUPPLY_PROP_CAPACITY,
 154         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 155         POWER_SUPPLY_PROP_TEMP,
 156         POWER_SUPPLY_PROP_TECHNOLOGY,
 157         POWER_SUPPLY_PROP_CHARGE_FULL,
 158         POWER_SUPPLY_PROP_CHARGE_NOW,
 159         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 160         POWER_SUPPLY_PROP_MANUFACTURER,
 161 };
 162
 163 static enum power_supply_property bq27742_battery_props[] = {
 164         POWER_SUPPLY_PROP_STATUS,
 165         POWER_SUPPLY_PROP_PRESENT,
 166         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 167         POWER_SUPPLY_PROP_CURRENT_NOW,
 168         POWER_SUPPLY_PROP_CAPACITY,
 169         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 170         POWER_SUPPLY_PROP_TEMP,
 171         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 172         POWER_SUPPLY_PROP_TECHNOLOGY,
 173         POWER_SUPPLY_PROP_CHARGE_FULL,
 174         POWER_SUPPLY_PROP_CHARGE_NOW,
 175         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 176         POWER_SUPPLY_PROP_CYCLE_COUNT,
 177         POWER_SUPPLY_PROP_POWER_AVG,
 178         POWER_SUPPLY_PROP_HEALTH,
 179         POWER_SUPPLY_PROP_MANUFACTURER,
 180 };
 181
 182 static enum power_supply_property bq27510_battery_props[] = {
 183         POWER_SUPPLY_PROP_STATUS,
 184         POWER_SUPPLY_PROP_PRESENT,
 185         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 186         POWER_SUPPLY_PROP_CURRENT_NOW,
 187         POWER_SUPPLY_PROP_CAPACITY,
 188         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 189         POWER_SUPPLY_PROP_TEMP,
 190         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 191         POWER_SUPPLY_PROP_TECHNOLOGY,
 192         POWER_SUPPLY_PROP_CHARGE_FULL,
 193         POWER_SUPPLY_PROP_CHARGE_NOW,
 194         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 195         POWER_SUPPLY_PROP_CYCLE_COUNT,
 196         POWER_SUPPLY_PROP_POWER_AVG,
 197         POWER_SUPPLY_PROP_HEALTH,
 198         POWER_SUPPLY_PROP_MANUFACTURER,
 199 };
 200
 201 static unsigned int poll_interval = 360;
 202 module_param(poll_interval, uint, 0644);
 203 MODULE_PARM_DESC(poll_interval,
 204                  "battery poll interval in seconds - 0 disables polling");
 205
 206 /*
 207  * Common code for BQ27xxx devices
 208  */
 209
 210 static inline int bq27xxx_read(struct bq27xxx_device_info *di, u8 reg,
 211                                bool single)
 212 {
 213         if (di->chip == BQ27425)
 214                 return di->bus.read(di, reg - BQ27425_REG_OFFSET, single);
 215         return di->bus.read(di, reg, single);
 216 }
 217
 218 /*
 219  * Higher versions of the chip like BQ27425 and BQ27500
 220  * differ from BQ27000 and BQ27200 in calculation of certain
 221  * parameters. Hence we need to check for the chip type.
 222  */
 223 static bool bq27xxx_is_chip_version_higher(struct bq27xxx_device_info *di)
 224 {
 225         if (di->chip == BQ27425 || di->chip == BQ27500 || di->chip == BQ27742
 226             || di->chip == BQ27510)
 227                 return true;
 228         return false;
 229 }
 230
 231 /*
 232  * Return the battery Relative State-of-Charge
 233  * Or < 0 if something fails.
 234  */
 235 static int bq27xxx_battery_read_rsoc(struct bq27xxx_device_info *di)
 236 {
 237         int rsoc;
 238
 239         if (di->chip == BQ27500 || di->chip == BQ27742)
 240                 rsoc = bq27xxx_read(di, BQ27500_REG_SOC, false);
 241         else if (di->chip == BQ27510)
 242                 rsoc = bq27xxx_read(di, BQ27510_REG_SOC, false);
 243         else if (di->chip == BQ27425)
 244                 rsoc = bq27xxx_read(di, BQ27425_REG_SOC, false);
 245         else
 246                 rsoc = bq27xxx_read(di, BQ27000_REG_RSOC, true);
 247
 248         if (rsoc < 0)
 249                 dev_dbg(di->dev, "error reading relative State-of-Charge\n");
 250
 251         return rsoc;
 252 }
 253
 254 /*
 255  * Return a battery charge value in µAh
 256  * Or < 0 if something fails.
 257  */
 258 static int bq27xxx_battery_read_charge(struct bq27xxx_device_info *di, u8 reg)
 259 {
 260         int charge;
 261
 262         charge = bq27xxx_read(di, reg, false);
 263         if (charge < 0) {
 264                 dev_dbg(di->dev, "error reading charge register %02x: %d\n",
 265                         reg, charge);
 266                 return charge;
 267         }
 268
 269         if (bq27xxx_is_chip_version_higher(di))
 270                 charge *= 1000;
 271         else
 272                 charge = charge * 3570 / BQ27XXX_RS;
 273
 274         return charge;
 275 }
 276
 277 /*
 278  * Return the battery Nominal available capaciy in µAh
 279  * Or < 0 if something fails.
 280  */
 281 static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
 282 {
 283         int flags;
 284         bool is_bq27500 = di->chip == BQ27500;
 285         bool is_bq27742 = di->chip == BQ27742;
 286         bool is_higher = bq27xxx_is_chip_version_higher(di);
 287         bool flags_1b = !(is_bq27500 || is_bq27742);
 288
 289         flags = bq27xxx_read(di, BQ27x00_REG_FLAGS, flags_1b);
 290         if (flags >= 0 && !is_higher && (flags & BQ27000_FLAG_CI))
 291                 return -ENODATA;
 292
 293         return bq27xxx_battery_read_charge(di, BQ27x00_REG_NAC);
 294 }
 295
 296 /*
 297  * Return the battery Last measured discharge in µAh
 298  * Or < 0 if something fails.
 299  */
 300 static inline int bq27xxx_battery_read_lmd(struct bq27xxx_device_info *di)
 301 {
 302         return bq27xxx_battery_read_charge(di, BQ27x00_REG_LMD);
 303 }
 304
 305 /*
 306  * Return the battery Initial last measured discharge in µAh
 307  * Or < 0 if something fails.
 308  */
 309 static int bq27xxx_battery_read_ilmd(struct bq27xxx_device_info *di)
 310 {
 311         int ilmd;
 312
 313         if (bq27xxx_is_chip_version_higher(di)) {
 314                 if (di->chip == BQ27425)
 315                         ilmd = bq27xxx_read(di, BQ27425_REG_DCAP, false);
 316                 else if (di->chip == BQ27510)
 317                         ilmd = bq27xxx_read(di, BQ27510_REG_DCAP, false);
 318                 else
 319                         ilmd = bq27xxx_read(di, BQ27500_REG_DCAP, false);
 320         } else {
 321                 ilmd = bq27xxx_read(di, BQ27000_REG_ILMD, true);
 322         }
 323
 324         if (ilmd < 0) {
 325                 dev_dbg(di->dev, "error reading initial last measured discharge\n");
 326                 return ilmd;
 327         }
 328
 329         if (bq27xxx_is_chip_version_higher(di))
 330                 ilmd *= 1000;
 331         else
 332                 ilmd = ilmd * 256 * 3570 / BQ27XXX_RS;
 333
 334         return ilmd;
 335 }
 336
 337 /*
 338  * Return the battery Available energy in µWh
 339  * Or < 0 if something fails.
 340  */
 341 static int bq27xxx_battery_read_energy(struct bq27xxx_device_info *di)
 342 {
 343         int ae;
 344
 345         ae = bq27xxx_read(di, BQ27x00_REG_AE, false);
 346         if (ae < 0) {
 347                 dev_dbg(di->dev, "error reading available energy\n");
 348                 return ae;
 349         }
 350
 351         if (di->chip == BQ27500)
 352                 ae *= 1000;
 353         else
 354                 ae = ae * 29200 / BQ27XXX_RS;
 355
 356         return ae;
 357 }
 358
 359 /*
 360  * Return the battery temperature in tenths of degree Kelvin
 361  * Or < 0 if something fails.
 362  */
 363 static int bq27xxx_battery_read_temperature(struct bq27xxx_device_info *di)
 364 {
 365         int temp;
 366
 367         temp = bq27xxx_read(di, BQ27x00_REG_TEMP, false);
 368         if (temp < 0) {
 369                 dev_err(di->dev, "error reading temperature\n");
 370                 return temp;
 371         }
 372
 373         if (!bq27xxx_is_chip_version_higher(di))
 374                 temp = 5 * temp / 2;
 375
 376         return temp;
 377 }
 378
 379 /*
 380  * Return the battery Cycle count total
 381  * Or < 0 if something fails.
 382  */
 383 static int bq27xxx_battery_read_cyct(struct bq27xxx_device_info *di)
 384 {
 385         int cyct;
 386
 387         if (di->chip == BQ27510)
 388                 cyct = bq27xxx_read(di, BQ27510_REG_CYCT, false);
 389         else
 390                 cyct = bq27xxx_read(di, BQ27x00_REG_CYCT, false);
 391         if (cyct < 0)
 392                 dev_err(di->dev, "error reading cycle count total\n");
 393
 394         return cyct;
 395 }
 396
 397 /*
 398  * Read a time register.
 399  * Return < 0 if something fails.
 400  */
 401 static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg)
 402 {
 403         int tval;
 404
 405         tval = bq27xxx_read(di, reg, false);
 406         if (tval < 0) {
 407                 dev_dbg(di->dev, "error reading time register %02x: %d\n",
 408                         reg, tval);
 409                 return tval;
 410         }
 411
 412         if (tval == 65535)
 413                 return -ENODATA;
 414
 415         return tval * 60;
 416 }
 417
 418 /*
 419  * Read a power avg register.
 420  * Return < 0 if something fails.
 421  */
 422 static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di, u8 reg)
 423 {
 424         int tval;
 425
 426         tval = bq27xxx_read(di, reg, false);
 427         if (tval < 0) {
 428                 dev_err(di->dev, "error reading power avg rgister  %02x: %d\n",
 429                         reg, tval);
 430                 return tval;
 431         }
 432
 433         if (di->chip == BQ27500)
 434                 return tval;
 435         else
 436                 return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
 437 }
 438
 439 /*
 440  * Read flag register.
 441  * Return < 0 if something fails.
 442  */
 443 static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
 444 {
 445         int tval;
 446
 447         tval = bq27xxx_read(di, BQ27x00_REG_FLAGS, false);
 448         if (tval < 0) {
 449                 dev_err(di->dev, "error reading flag register:%d\n", tval);
 450                 return tval;
 451         }
 452
 453         if (di->chip == BQ27500) {
 454                 if (tval & BQ27500_FLAG_SOCF)
 455                         tval = POWER_SUPPLY_HEALTH_DEAD;
 456                 else if (tval & BQ27500_FLAG_OTC)
 457                         tval = POWER_SUPPLY_HEALTH_OVERHEAT;
 458                 else
 459                         tval = POWER_SUPPLY_HEALTH_GOOD;
 460                 return tval;
 461         } else if (di->chip == BQ27510) {
 462                 if (tval & BQ27500_FLAG_OTC)
 463                         return POWER_SUPPLY_HEALTH_OVERHEAT;
 464                 return POWER_SUPPLY_HEALTH_GOOD;
 465         } else {
 466                 if (tval & BQ27000_FLAG_EDV1)
 467                         tval = POWER_SUPPLY_HEALTH_DEAD;
 468                 else
 469                         tval = POWER_SUPPLY_HEALTH_GOOD;
 470                 return tval;
 471         }
 472
 473         return -1;
 474 }
 475
 476 static void bq27xxx_battery_update(struct bq27xxx_device_info *di)
 477 {
 478         struct bq27xxx_reg_cache cache = {0, };
 479         bool is_bq27500 = di->chip == BQ27500;
 480         bool is_bq27510 = di->chip == BQ27510;
 481         bool is_bq27425 = di->chip == BQ27425;
 482         bool is_bq27742 = di->chip == BQ27742;
 483         bool flags_1b = !(is_bq27500 || is_bq27742);
 484
 485         cache.flags = bq27xxx_read(di, BQ27x00_REG_FLAGS, flags_1b);
 486         if ((cache.flags & 0xff) == 0xff)
 487                 /* read error */
 488                 cache.flags = -1;
 489         if (cache.flags >= 0) {
 490                 if (!is_bq27500 && !is_bq27425 && !is_bq27742 && !is_bq27510
 491                                 && (cache.flags & BQ27000_FLAG_CI)) {
 492                         dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
 493                         cache.capacity = -ENODATA;
 494                         cache.energy = -ENODATA;
 495                         cache.time_to_empty = -ENODATA;
 496                         cache.time_to_empty_avg = -ENODATA;
 497                         cache.time_to_full = -ENODATA;
 498                         cache.charge_full = -ENODATA;
 499                         cache.health = -ENODATA;
 500                 } else {
 501                         cache.capacity = bq27xxx_battery_read_rsoc(di);
 502                         if (is_bq27742 || is_bq27510)
 503                                 cache.time_to_empty =
 504                                         bq27xxx_battery_read_time(di,
 505                                                         BQ27x00_REG_TTE);
 506                         else if (!is_bq27425) {
 507                                 cache.energy = bq27xxx_battery_read_energy(di);
 508                                 cache.time_to_empty =
 509                                         bq27xxx_battery_read_time(di,
 510                                                         BQ27x00_REG_TTE);
 511                                 cache.time_to_empty_avg =
 512                                         bq27xxx_battery_read_time(di,
 513                                                         BQ27x00_REG_TTECP);
 514                                 cache.time_to_full =
 515                                         bq27xxx_battery_read_time(di,
 516                                                         BQ27x00_REG_TTF);
 517                         }
 518                         cache.charge_full = bq27xxx_battery_read_lmd(di);
 519                         cache.health = bq27xxx_battery_read_health(di);
 520                 }
 521                 cache.temperature = bq27xxx_battery_read_temperature(di);
 522                 if (!is_bq27425)
 523                         cache.cycle_count = bq27xxx_battery_read_cyct(di);
 524                 if (is_bq27742)
 525                         cache.power_avg =
 526                                 bq27xxx_battery_read_pwr_avg(di,
 527                                                 BQ27742_POWER_AVG);
 528                 else
 529                         cache.power_avg =
 530                                 bq27xxx_battery_read_pwr_avg(di,
 531                                                 BQ27x00_POWER_AVG);
 532
 533                 /* We only have to read charge design full once */
 534                 if (di->charge_design_full <= 0)
 535                         di->charge_design_full = bq27xxx_battery_read_ilmd(di);
 536         }
 537
 538         if (di->cache.capacity != cache.capacity)
 539                 power_supply_changed(di->bat);
 540
 541         if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
 542                 di->cache = cache;
 543
 544         di->last_update = jiffies;
 545 }
 546
 547 static void bq27xxx_battery_poll(struct work_struct *work)
 548 {
 549         struct bq27xxx_device_info *di =
 550                 container_of(work, struct bq27xxx_device_info, work.work);
 551
 552         bq27xxx_battery_update(di);
 553
 554         if (poll_interval > 0) {
 555                 /* The timer does not have to be accurate. */
 556                 set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
 557                 schedule_delayed_work(&di->work, poll_interval * HZ);
 558         }
 559 }
 560
 561 /*
 562  * Return the battery average current in µA
 563  * Note that current can be negative signed as well
 564  * Or 0 if something fails.
 565  */
 566 static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
 567                                    union power_supply_propval *val)
 568 {
 569         int curr;
 570         int flags;
 571
 572         curr = bq27xxx_read(di, BQ27x00_REG_AI, false);
 573         if (curr < 0) {
 574                 dev_err(di->dev, "error reading current\n");
 575                 return curr;
 576         }
 577
 578         if (bq27xxx_is_chip_version_higher(di)) {
 579                 /* bq27500 returns signed value */
 580                 val->intval = (int)((s16)curr) * 1000;
 581         } else {
 582                 flags = bq27xxx_read(di, BQ27x00_REG_FLAGS, false);
 583                 if (flags & BQ27000_FLAG_CHGS) {
 584                         dev_dbg(di->dev, "negative current!\n");
 585                         curr = -curr;
 586                 }
 587
 588                 val->intval = curr * 3570 / BQ27XXX_RS;
 589         }
 590
 591         return 0;
 592 }
 593
 594 static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
 595                                   union power_supply_propval *val)
 596 {
 597         int status;
 598
 599         if (bq27xxx_is_chip_version_higher(di)) {
 600                 if (di->cache.flags & BQ27500_FLAG_FC)
 601                         status = POWER_SUPPLY_STATUS_FULL;
 602                 else if (di->cache.flags & BQ27500_FLAG_DSC)
 603                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 604                 else
 605                         status = POWER_SUPPLY_STATUS_CHARGING;
 606         } else {
 607                 if (di->cache.flags & BQ27000_FLAG_FC)
 608                         status = POWER_SUPPLY_STATUS_FULL;
 609                 else if (di->cache.flags & BQ27000_FLAG_CHGS)
 610                         status = POWER_SUPPLY_STATUS_CHARGING;
 611                 else if (power_supply_am_i_supplied(di->bat))
 612                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 613                 else
 614                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 615         }
 616
 617         val->intval = status;
 618
 619         return 0;
 620 }
 621
 622 static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
 623                                           union power_supply_propval *val)
 624 {
 625         int level;
 626
 627         if (bq27xxx_is_chip_version_higher(di)) {
 628                 if (di->cache.flags & BQ27500_FLAG_FC)
 629                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 630                 else if (di->cache.flags & BQ27500_FLAG_SOC1)
 631                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 632                 else if (di->cache.flags & BQ27500_FLAG_SOCF)
 633                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 634                 else
 635                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 636         } else {
 637                 if (di->cache.flags & BQ27000_FLAG_FC)
 638                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 639                 else if (di->cache.flags & BQ27000_FLAG_EDV1)
 640                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 641                 else if (di->cache.flags & BQ27000_FLAG_EDVF)
 642                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 643                 else
 644                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 645         }
 646
 647         val->intval = level;
 648
 649         return 0;
 650 }
 651
 652 /*
 653  * Return the battery Voltage in millivolts
 654  * Or < 0 if something fails.
 655  */
 656 static int bq27xxx_battery_voltage(struct bq27xxx_device_info *di,
 657                                    union power_supply_propval *val)
 658 {
 659         int volt;
 660
 661         volt = bq27xxx_read(di, BQ27x00_REG_VOLT, false);
 662         if (volt < 0) {
 663                 dev_err(di->dev, "error reading voltage\n");
 664                 return volt;
 665         }
 666
 667         val->intval = volt * 1000;
 668
 669         return 0;
 670 }
 671
 672 static int bq27xxx_simple_value(int value,
 673                                 union power_supply_propval *val)
 674 {
 675         if (value < 0)
 676                 return value;
 677
 678         val->intval = value;
 679
 680         return 0;
 681 }
 682
 683 static int bq27xxx_battery_get_property(struct power_supply *psy,
 684                                         enum power_supply_property psp,
 685                                         union power_supply_propval *val)
 686 {
 687         int ret = 0;
 688         struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
 689
 690         mutex_lock(&di->lock);
 691         if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
 692                 cancel_delayed_work_sync(&di->work);
 693                 bq27xxx_battery_poll(&di->work.work);
 694         }
 695         mutex_unlock(&di->lock);
 696
 697         if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
 698                 return -ENODEV;
 699
 700         switch (psp) {
 701         case POWER_SUPPLY_PROP_STATUS:
 702                 ret = bq27xxx_battery_status(di, val);
 703                 break;
 704         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 705                 ret = bq27xxx_battery_voltage(di, val);
 706                 break;
 707         case POWER_SUPPLY_PROP_PRESENT:
 708                 val->intval = di->cache.flags < 0 ? 0 : 1;
 709                 break;
 710         case POWER_SUPPLY_PROP_CURRENT_NOW:
 711                 ret = bq27xxx_battery_current(di, val);
 712                 break;
 713         case POWER_SUPPLY_PROP_CAPACITY:
 714                 ret = bq27xxx_simple_value(di->cache.capacity, val);
 715                 break;
 716         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 717                 ret = bq27xxx_battery_capacity_level(di, val);
 718                 break;
 719         case POWER_SUPPLY_PROP_TEMP:
 720                 ret = bq27xxx_simple_value(di->cache.temperature, val);
 721                 if (ret == 0)
 722                         val->intval -= 2731;
 723                 break;
 724         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
 725                 ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
 726                 break;
 727         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 728                 ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
 729                 break;
 730         case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
 731                 ret = bq27xxx_simple_value(di->cache.time_to_full, val);
 732                 break;
 733         case POWER_SUPPLY_PROP_TECHNOLOGY:
 734                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 735                 break;
 736         case POWER_SUPPLY_PROP_CHARGE_NOW:
 737                 ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
 738                 break;
 739         case POWER_SUPPLY_PROP_CHARGE_FULL:
 740                 ret = bq27xxx_simple_value(di->cache.charge_full, val);
 741                 break;
 742         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 743                 ret = bq27xxx_simple_value(di->charge_design_full, val);
 744                 break;
 745         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 746                 ret = bq27xxx_simple_value(di->cache.cycle_count, val);
 747                 break;
 748         case POWER_SUPPLY_PROP_ENERGY_NOW:
 749                 ret = bq27xxx_simple_value(di->cache.energy, val);
 750                 break;
 751         case POWER_SUPPLY_PROP_POWER_AVG:
 752                 ret = bq27xxx_simple_value(di->cache.power_avg, val);
 753                 break;
 754         case POWER_SUPPLY_PROP_HEALTH:
 755                 ret = bq27xxx_simple_value(di->cache.health, val);
 756                 break;
 757         case POWER_SUPPLY_PROP_MANUFACTURER:
 758                 val->strval = BQ27XXX_MANUFACTURER;
 759                 break;
 760         default:
 761                 return -EINVAL;
 762         }
 763
 764         return ret;
 765 }
 766
 767 static void bq27xxx_external_power_changed(struct power_supply *psy)
 768 {
 769         struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
 770
 771         cancel_delayed_work_sync(&di->work);
 772         schedule_delayed_work(&di->work, 0);
 773 }
 774
 775 static int bq27xxx_powersupply_init(struct bq27xxx_device_info *di,
 776                                     const char *name)
 777 {
 778         int ret;
 779         struct power_supply_desc *psy_desc;
 780         struct power_supply_config psy_cfg = { .drv_data = di, };
 781
 782         psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
 783         if (!psy_desc)
 784                 return -ENOMEM;
 785
 786         psy_desc->name = name;
 787         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 788         if (di->chip == BQ27425) {
 789                 psy_desc->properties = bq27425_battery_props;
 790                 psy_desc->num_properties = ARRAY_SIZE(bq27425_battery_props);
 791         } else if (di->chip == BQ27742) {
 792                 psy_desc->properties = bq27742_battery_props;
 793                 psy_desc->num_properties = ARRAY_SIZE(bq27742_battery_props);
 794         } else if (di->chip == BQ27510) {
 795                 psy_desc->properties = bq27510_battery_props;
 796                 psy_desc->num_properties = ARRAY_SIZE(bq27510_battery_props);
 797         } else {
 798                 psy_desc->properties = bq27x00_battery_props;
 799                 psy_desc->num_properties = ARRAY_SIZE(bq27x00_battery_props);
 800         }
 801         psy_desc->get_property = bq27xxx_battery_get_property;
 802         psy_desc->external_power_changed = bq27xxx_external_power_changed;
 803
 804         INIT_DELAYED_WORK(&di->work, bq27xxx_battery_poll);
 805         mutex_init(&di->lock);
 806
 807         di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
 808         if (IS_ERR(di->bat)) {
 809                 ret = PTR_ERR(di->bat);
 810                 dev_err(di->dev, "failed to register battery: %d\n", ret);
 811                 return ret;
 812         }
 813
 814         dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
 815
 816         bq27xxx_battery_update(di);
 817
 818         return 0;
 819 }
 820
 821 static void bq27xxx_powersupply_unregister(struct bq27xxx_device_info *di)
 822 {
 823         /*
 824          * power_supply_unregister call bq27xxx_battery_get_property which
 825          * call bq27xxx_battery_poll.
 826          * Make sure that bq27xxx_battery_poll will not call
 827          * schedule_delayed_work again after unregister (which cause OOPS).
 828          */
 829         poll_interval = 0;
 830
 831         cancel_delayed_work_sync(&di->work);
 832
 833         power_supply_unregister(di->bat);
 834
 835         mutex_destroy(&di->lock);
 836 }
 837
 838 /* i2c specific code */
 839 #ifdef CONFIG_BATTERY_BQ27XXX_I2C
 840
 841 /* If the system has several batteries we need a different name for each
 842  * of them...
 843  */
 844 static DEFINE_IDR(battery_id);
 845 static DEFINE_MUTEX(battery_mutex);
 846
 847 static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
 848                                     bool single)
 849 {
 850         struct i2c_client *client = to_i2c_client(di->dev);
 851         struct i2c_msg msg[2];
 852         unsigned char data[2];
 853         int ret;
 854
 855         if (!client->adapter)
 856                 return -ENODEV;
 857
 858         msg[0].addr = client->addr;
 859         msg[0].flags = 0;
 860         msg[0].buf = &reg;
 861         msg[0].len = sizeof(reg);
 862         msg[1].addr = client->addr;
 863         msg[1].flags = I2C_M_RD;
 864         msg[1].buf = data;
 865         if (single)
 866                 msg[1].len = 1;
 867         else
 868                 msg[1].len = 2;
 869
 870         ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
 871         if (ret < 0)
 872                 return ret;
 873
 874         if (!single)
 875                 ret = get_unaligned_le16(data);
 876         else
 877                 ret = data[0];
 878
 879         return ret;
 880 }
 881
 882 static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
 883                                      const struct i2c_device_id *id)
 884 {
 885         char *name;
 886         struct bq27xxx_device_info *di;
 887         int num;
 888         int retval = 0;
 889
 890         /* Get new ID for the new battery device */
 891         mutex_lock(&battery_mutex);
 892         num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
 893         mutex_unlock(&battery_mutex);
 894         if (num < 0)
 895                 return num;
 896
 897         name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
 898         if (!name) {
 899                 retval = -ENOMEM;
 900                 goto batt_failed;
 901         }
 902
 903         di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
 904         if (!di) {
 905                 retval = -ENOMEM;
 906                 goto batt_failed;
 907         }
 908
 909         di->id = num;
 910         di->dev = &client->dev;
 911         di->chip = id->driver_data;
 912         di->bus.read = &bq27xxx_battery_i2c_read;
 913
 914         retval = bq27xxx_powersupply_init(di, name);
 915         if (retval)
 916                 goto batt_failed;
 917
 918         i2c_set_clientdata(client, di);
 919
 920         return 0;
 921
 922 batt_failed:
 923         mutex_lock(&battery_mutex);
 924         idr_remove(&battery_id, num);
 925         mutex_unlock(&battery_mutex);
 926
 927         return retval;
 928 }
 929
 930 static int bq27xxx_battery_i2c_remove(struct i2c_client *client)
 931 {
 932         struct bq27xxx_device_info *di = i2c_get_clientdata(client);
 933
 934         bq27xxx_powersupply_unregister(di);
 935
 936         mutex_lock(&battery_mutex);
 937         idr_remove(&battery_id, di->id);
 938         mutex_unlock(&battery_mutex);
 939
 940         return 0;
 941 }
 942
 943 static const struct i2c_device_id bq27xxx_id[] = {
 944         { "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */
 945         { "bq27500", BQ27500 },
 946         { "bq27425", BQ27425 },
 947         { "bq27742", BQ27742 },
 948         { "bq27510", BQ27510 },
 949         {},
 950 };
 951 MODULE_DEVICE_TABLE(i2c, bq27xxx_id);
 952
 953 static struct i2c_driver bq27xxx_battery_i2c_driver = {
 954         .driver = {
 955                 .name = "bq27xxx-battery",
 956         },
 957         .probe = bq27xxx_battery_i2c_probe,
 958         .remove = bq27xxx_battery_i2c_remove,
 959         .id_table = bq27xxx_id,
 960 };
 961
 962 static inline int bq27xxx_battery_i2c_init(void)
 963 {
 964         int ret = i2c_add_driver(&bq27xxx_battery_i2c_driver);
 965
 966         if (ret)
 967                 pr_err("Unable to register BQ27xxx i2c driver\n");
 968
 969         return ret;
 970 }
 971
 972 static inline void bq27xxx_battery_i2c_exit(void)
 973 {
 974         i2c_del_driver(&bq27xxx_battery_i2c_driver);
 975 }
 976
 977 #else
 978
 979 static inline int bq27xxx_battery_i2c_init(void) { return 0; }
 980 static inline void bq27xxx_battery_i2c_exit(void) {};
 981
 982 #endif
 983
 984 /* platform specific code */
 985 #ifdef CONFIG_BATTERY_BQ27XXX_PLATFORM
 986
 987 static int bq27xxx_battery_platform_read(struct bq27xxx_device_info *di, u8 reg,
 988                                          bool single)
 989 {
 990         struct device *dev = di->dev;
 991         struct bq27xxx_platform_data *pdata = dev->platform_data;
 992         unsigned int timeout = 3;
 993         int upper, lower;
 994         int temp;
 995
 996         if (!single) {
 997                 /* Make sure the value has not changed in between reading the
 998                  * lower and the upper part */
 999                 upper = pdata->read(dev, reg + 1);
1000                 do {
1001                         temp = upper;
1002                         if (upper < 0)
1003                                 return upper;
1004
1005                         lower = pdata->read(dev, reg);
1006                         if (lower < 0)
1007                                 return lower;
1008
1009                         upper = pdata->read(dev, reg + 1);
1010                 } while (temp != upper && --timeout);
1011
1012                 if (timeout == 0)
1013                         return -EIO;
1014
1015                 return (upper << 8) | lower;
1016         }
1017
1018         return pdata->read(dev, reg);
1019 }
1020
1021 static int bq27xxx_battery_platform_probe(struct platform_device *pdev)
1022 {
1023         struct bq27xxx_device_info *di;
1024         struct bq27xxx_platform_data *pdata = pdev->dev.platform_data;
1025         const char *name;
1026
1027         if (!pdata) {
1028                 dev_err(&pdev->dev, "no platform_data supplied\n");
1029                 return -EINVAL;
1030         }
1031
1032         if (!pdata->read) {
1033                 dev_err(&pdev->dev, "no hdq read callback supplied\n");
1034                 return -EINVAL;
1035         }
1036
1037         if (!pdata->chip) {
1038                 dev_err(&pdev->dev, "no device supplied\n");
1039                 return -EINVAL;
1040         }
1041
1042         di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1043         if (!di)
1044                 return -ENOMEM;
1045
1046         platform_set_drvdata(pdev, di);
1047
1048         di->dev = &pdev->dev;
1049         di->chip = pdata->chip;
1050
1051         name = pdata->name ?: dev_name(&pdev->dev);
1052         di->bus.read = &bq27xxx_battery_platform_read;
1053
1054         return bq27xxx_powersupply_init(di, name);
1055 }
1056
1057 static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
1058 {
1059         struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
1060
1061         bq27xxx_powersupply_unregister(di);
1062
1063         return 0;
1064 }
1065
1066 static struct platform_driver bq27xxx_battery_platform_driver = {
1067         .probe  = bq27xxx_battery_platform_probe,
1068         .remove = bq27xxx_battery_platform_remove,
1069         .driver = {
1070                 .name = "bq27000-battery",
1071         },
1072 };
1073
1074 static inline int bq27xxx_battery_platform_init(void)
1075 {
1076         int ret = platform_driver_register(&bq27xxx_battery_platform_driver);
1077
1078         if (ret)
1079                 pr_err("Unable to register BQ27xxx platform driver\n");
1080
1081         return ret;
1082 }
1083
1084 static inline void bq27xxx_battery_platform_exit(void)
1085 {
1086         platform_driver_unregister(&bq27xxx_battery_platform_driver);
1087 }
1088
1089 #else
1090
1091 static inline int bq27xxx_battery_platform_init(void) { return 0; }
1092 static inline void bq27xxx_battery_platform_exit(void) {};
1093
1094 #endif
1095
1096 /*
1097  * Module stuff
1098  */
1099
1100 static int __init bq27xxx_battery_init(void)
1101 {
1102         int ret;
1103
1104         ret = bq27xxx_battery_i2c_init();
1105         if (ret)
1106                 return ret;
1107
1108         ret = bq27xxx_battery_platform_init();
1109         if (ret)
1110                 bq27xxx_battery_i2c_exit();
1111
1112         return ret;
1113 }
1114 module_init(bq27xxx_battery_init);
1115
1116 static void __exit bq27xxx_battery_exit(void)
1117 {
1118         bq27xxx_battery_platform_exit();
1119         bq27xxx_battery_i2c_exit();
1120 }
1121 module_exit(bq27xxx_battery_exit);
1122
1123 #ifdef CONFIG_BATTERY_BQ27XXX_PLATFORM
1124 MODULE_ALIAS("platform:bq27000-battery");
1125 #endif
1126
1127 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1128 MODULE_DESCRIPTION("BQ27xxx battery monitor driver");
1129 MODULE_LICENSE("GPL");