drivers/power/bq27x00_battery.c

   1 /*
   2  * BQ27x00 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  */
  20
  21 /*
  22  * Datasheets:
  23  * http://focus.ti.com/docs/prod/folders/print/bq27000.html
  24  * http://focus.ti.com/docs/prod/folders/print/bq27500.html
  25  * http://www.ti.com/product/bq27425-g1
  26  * http://www.ti.com/product/BQ27742-G1
  27  */
  28
  29 #include <linux/device.h>
  30 #include <linux/module.h>
  31 #include <linux/param.h>
  32 #include <linux/jiffies.h>
  33 #include <linux/workqueue.h>
  34 #include <linux/delay.h>
  35 #include <linux/platform_device.h>
  36 #include <linux/power_supply.h>
  37 #include <linux/idr.h>
  38 #include <linux/i2c.h>
  39 #include <linux/slab.h>
  40 #include <asm/unaligned.h>
  41
  42 #include <linux/power/bq27x00_battery.h>
  43
  44 #define DRIVER_VERSION                  "1.2.0"
  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 /* bq27425 register addresses are same as bq27x00 addresses minus 4 */
  78 #define BQ27425_REG_OFFSET              0x04
  79 #define BQ27425_REG_SOC                 0x18 /* Register address plus offset */
  80
  81 #define BQ27000_RS                      20 /* Resistor sense */
  82 #define BQ27x00_POWER_CONSTANT          (256 * 29200 / 1000)
  83
  84 struct bq27x00_device_info;
  85 struct bq27x00_access_methods {
  86         int (*read)(struct bq27x00_device_info *di, u8 reg, bool single);
  87 };
  88
  89 enum bq27x00_chip { BQ27000, BQ27500, BQ27425, BQ27742};
  90
  91 struct bq27x00_reg_cache {
  92         int temperature;
  93         int time_to_empty;
  94         int time_to_empty_avg;
  95         int time_to_full;
  96         int charge_full;
  97         int cycle_count;
  98         int capacity;
  99         int energy;
 100         int flags;
 101         int power_avg;
 102         int health;
 103 };
 104
 105 struct bq27x00_device_info {
 106         struct device           *dev;
 107         int                     id;
 108         enum bq27x00_chip       chip;
 109
 110         struct bq27x00_reg_cache cache;
 111         int charge_design_full;
 112
 113         unsigned long last_update;
 114         struct delayed_work work;
 115
 116         struct power_supply     bat;
 117
 118         struct bq27x00_access_methods bus;
 119
 120         struct mutex lock;
 121 };
 122
 123 static enum power_supply_property bq27x00_battery_props[] = {
 124         POWER_SUPPLY_PROP_STATUS,
 125         POWER_SUPPLY_PROP_PRESENT,
 126         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 127         POWER_SUPPLY_PROP_CURRENT_NOW,
 128         POWER_SUPPLY_PROP_CAPACITY,
 129         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 130         POWER_SUPPLY_PROP_TEMP,
 131         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 132         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 133         POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 134         POWER_SUPPLY_PROP_TECHNOLOGY,
 135         POWER_SUPPLY_PROP_CHARGE_FULL,
 136         POWER_SUPPLY_PROP_CHARGE_NOW,
 137         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 138         POWER_SUPPLY_PROP_CYCLE_COUNT,
 139         POWER_SUPPLY_PROP_ENERGY_NOW,
 140         POWER_SUPPLY_PROP_POWER_AVG,
 141         POWER_SUPPLY_PROP_HEALTH,
 142 };
 143
 144 static enum power_supply_property bq27425_battery_props[] = {
 145         POWER_SUPPLY_PROP_STATUS,
 146         POWER_SUPPLY_PROP_PRESENT,
 147         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 148         POWER_SUPPLY_PROP_CURRENT_NOW,
 149         POWER_SUPPLY_PROP_CAPACITY,
 150         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 151         POWER_SUPPLY_PROP_TEMP,
 152         POWER_SUPPLY_PROP_TECHNOLOGY,
 153         POWER_SUPPLY_PROP_CHARGE_FULL,
 154         POWER_SUPPLY_PROP_CHARGE_NOW,
 155         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 156 };
 157
 158 static enum power_supply_property bq27742_battery_props[] = {
 159         POWER_SUPPLY_PROP_STATUS,
 160         POWER_SUPPLY_PROP_PRESENT,
 161         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 162         POWER_SUPPLY_PROP_CURRENT_NOW,
 163         POWER_SUPPLY_PROP_CAPACITY,
 164         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 165         POWER_SUPPLY_PROP_TEMP,
 166         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 167         POWER_SUPPLY_PROP_TECHNOLOGY,
 168         POWER_SUPPLY_PROP_CHARGE_FULL,
 169         POWER_SUPPLY_PROP_CHARGE_NOW,
 170         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 171         POWER_SUPPLY_PROP_CYCLE_COUNT,
 172         POWER_SUPPLY_PROP_POWER_AVG,
 173         POWER_SUPPLY_PROP_HEALTH,
 174 };
 175
 176 static unsigned int poll_interval = 360;
 177 module_param(poll_interval, uint, 0644);
 178 MODULE_PARM_DESC(poll_interval, "battery poll interval in seconds - " \
 179                                 "0 disables polling");
 180
 181 /*
 182  * Common code for BQ27x00 devices
 183  */
 184
 185 static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg,
 186                 bool single)
 187 {
 188         if (di->chip == BQ27425)
 189                 return di->bus.read(di, reg - BQ27425_REG_OFFSET, single);
 190         return di->bus.read(di, reg, single);
 191 }
 192
 193 /*
 194  * Higher versions of the chip like BQ27425 and BQ27500
 195  * differ from BQ27000 and BQ27200 in calculation of certain
 196  * parameters. Hence we need to check for the chip type.
 197  */
 198 static bool bq27xxx_is_chip_version_higher(struct bq27x00_device_info *di)
 199 {
 200         if (di->chip == BQ27425 || di->chip == BQ27500 || di->chip == BQ27742)
 201                 return true;
 202         return false;
 203 }
 204
 205 /*
 206  * Return the battery Relative State-of-Charge
 207  * Or < 0 if something fails.
 208  */
 209 static int bq27x00_battery_read_rsoc(struct bq27x00_device_info *di)
 210 {
 211         int rsoc;
 212
 213         if (di->chip == BQ27500 || di->chip == BQ27742)
 214                 rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
 215         else if (di->chip == BQ27425)
 216                 rsoc = bq27x00_read(di, BQ27425_REG_SOC, false);
 217         else
 218                 rsoc = bq27x00_read(di, BQ27000_REG_RSOC, true);
 219
 220         if (rsoc < 0)
 221                 dev_dbg(di->dev, "error reading relative State-of-Charge\n");
 222
 223         return rsoc;
 224 }
 225
 226 /*
 227  * Return a battery charge value in µAh
 228  * Or < 0 if something fails.
 229  */
 230 static int bq27x00_battery_read_charge(struct bq27x00_device_info *di, u8 reg)
 231 {
 232         int charge;
 233
 234         charge = bq27x00_read(di, reg, false);
 235         if (charge < 0) {
 236                 dev_dbg(di->dev, "error reading charge register %02x: %d\n",
 237                         reg, charge);
 238                 return charge;
 239         }
 240
 241         if (bq27xxx_is_chip_version_higher(di))
 242                 charge *= 1000;
 243         else
 244                 charge = charge * 3570 / BQ27000_RS;
 245
 246         return charge;
 247 }
 248
 249 /*
 250  * Return the battery Nominal available capaciy in µAh
 251  * Or < 0 if something fails.
 252  */
 253 static inline int bq27x00_battery_read_nac(struct bq27x00_device_info *di)
 254 {
 255         int flags;
 256         bool is_bq27500 = di->chip == BQ27500;
 257         bool is_bq27742 = di->chip == BQ27742;
 258         bool is_higher = bq27xxx_is_chip_version_higher(di);
 259         bool flags_1b = !(is_bq27500 || is_bq27742);
 260
 261         flags = bq27x00_read(di, BQ27x00_REG_FLAGS, flags_1b);
 262         if (flags >= 0 && !is_higher && (flags & BQ27000_FLAG_CI))
 263                 return -ENODATA;
 264
 265         return bq27x00_battery_read_charge(di, BQ27x00_REG_NAC);
 266 }
 267
 268 /*
 269  * Return the battery Last measured discharge in µAh
 270  * Or < 0 if something fails.
 271  */
 272 static inline int bq27x00_battery_read_lmd(struct bq27x00_device_info *di)
 273 {
 274         return bq27x00_battery_read_charge(di, BQ27x00_REG_LMD);
 275 }
 276
 277 /*
 278  * Return the battery Initial last measured discharge in µAh
 279  * Or < 0 if something fails.
 280  */
 281 static int bq27x00_battery_read_ilmd(struct bq27x00_device_info *di)
 282 {
 283         int ilmd;
 284
 285         if (bq27xxx_is_chip_version_higher(di))
 286                 ilmd = bq27x00_read(di, BQ27500_REG_DCAP, false);
 287         else
 288                 ilmd = bq27x00_read(di, BQ27000_REG_ILMD, true);
 289
 290         if (ilmd < 0) {
 291                 dev_dbg(di->dev, "error reading initial last measured discharge\n");
 292                 return ilmd;
 293         }
 294
 295         if (bq27xxx_is_chip_version_higher(di))
 296                 ilmd *= 1000;
 297         else
 298                 ilmd = ilmd * 256 * 3570 / BQ27000_RS;
 299
 300         return ilmd;
 301 }
 302
 303 /*
 304  * Return the battery Available energy in µWh
 305  * Or < 0 if something fails.
 306  */
 307 static int bq27x00_battery_read_energy(struct bq27x00_device_info *di)
 308 {
 309         int ae;
 310
 311         ae = bq27x00_read(di, BQ27x00_REG_AE, false);
 312         if (ae < 0) {
 313                 dev_dbg(di->dev, "error reading available energy\n");
 314                 return ae;
 315         }
 316
 317         if (di->chip == BQ27500)
 318                 ae *= 1000;
 319         else
 320                 ae = ae * 29200 / BQ27000_RS;
 321
 322         return ae;
 323 }
 324
 325 /*
 326  * Return the battery temperature in tenths of degree Kelvin
 327  * Or < 0 if something fails.
 328  */
 329 static int bq27x00_battery_read_temperature(struct bq27x00_device_info *di)
 330 {
 331         int temp;
 332
 333         temp = bq27x00_read(di, BQ27x00_REG_TEMP, false);
 334         if (temp < 0) {
 335                 dev_err(di->dev, "error reading temperature\n");
 336                 return temp;
 337         }
 338
 339         if (!bq27xxx_is_chip_version_higher(di))
 340                 temp = 5 * temp / 2;
 341
 342         return temp;
 343 }
 344
 345 /*
 346  * Return the battery Cycle count total
 347  * Or < 0 if something fails.
 348  */
 349 static int bq27x00_battery_read_cyct(struct bq27x00_device_info *di)
 350 {
 351         int cyct;
 352
 353         cyct = bq27x00_read(di, BQ27x00_REG_CYCT, false);
 354         if (cyct < 0)
 355                 dev_err(di->dev, "error reading cycle count total\n");
 356
 357         return cyct;
 358 }
 359
 360 /*
 361  * Read a time register.
 362  * Return < 0 if something fails.
 363  */
 364 static int bq27x00_battery_read_time(struct bq27x00_device_info *di, u8 reg)
 365 {
 366         int tval;
 367
 368         tval = bq27x00_read(di, reg, false);
 369         if (tval < 0) {
 370                 dev_dbg(di->dev, "error reading time register %02x: %d\n",
 371                         reg, tval);
 372                 return tval;
 373         }
 374
 375         if (tval == 65535)
 376                 return -ENODATA;
 377
 378         return tval * 60;
 379 }
 380
 381 /*
 382  * Read a power avg register.
 383  * Return < 0 if something fails.
 384  */
 385 static int bq27x00_battery_read_pwr_avg(struct bq27x00_device_info *di, u8 reg)
 386 {
 387         int tval;
 388
 389         tval = bq27x00_read(di, reg, false);
 390         if (tval < 0) {
 391                 dev_err(di->dev, "error reading power avg rgister  %02x: %d\n",
 392                         reg, tval);
 393                 return tval;
 394         }
 395
 396         if (di->chip == BQ27500)
 397                 return tval;
 398         else
 399                 return (tval * BQ27x00_POWER_CONSTANT) / BQ27000_RS;
 400 }
 401
 402 /*
 403  * Read flag register.
 404  * Return < 0 if something fails.
 405  */
 406 static int bq27x00_battery_read_health(struct bq27x00_device_info *di)
 407 {
 408         int tval;
 409
 410         tval = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
 411         if (tval < 0) {
 412                 dev_err(di->dev, "error reading flag register:%d\n", tval);
 413                 return tval;
 414         }
 415
 416         if ((di->chip == BQ27500)) {
 417                 if (tval & BQ27500_FLAG_SOCF)
 418                         tval = POWER_SUPPLY_HEALTH_DEAD;
 419                 else if (tval & BQ27500_FLAG_OTC)
 420                         tval = POWER_SUPPLY_HEALTH_OVERHEAT;
 421                 else
 422                         tval = POWER_SUPPLY_HEALTH_GOOD;
 423                 return tval;
 424         } else {
 425                 if (tval & BQ27000_FLAG_EDV1)
 426                         tval = POWER_SUPPLY_HEALTH_DEAD;
 427                 else
 428                         tval = POWER_SUPPLY_HEALTH_GOOD;
 429                 return tval;
 430         }
 431
 432         return -1;
 433 }
 434
 435 static void bq27x00_update(struct bq27x00_device_info *di)
 436 {
 437         struct bq27x00_reg_cache cache = {0, };
 438         bool is_bq27500 = di->chip == BQ27500;
 439         bool is_bq27425 = di->chip == BQ27425;
 440         bool is_bq27742 = di->chip == BQ27742;
 441         bool flags_1b = !(is_bq27500 || is_bq27742);
 442
 443         cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, flags_1b);
 444         if ((cache.flags & 0xff) == 0xff)
 445                 /* read error */
 446                 cache.flags = -1;
 447         if (cache.flags >= 0) {
 448                 if (!is_bq27500 && !is_bq27425 && !is_bq27742
 449                                 && (cache.flags & BQ27000_FLAG_CI)) {
 450                         dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
 451                         cache.capacity = -ENODATA;
 452                         cache.energy = -ENODATA;
 453                         cache.time_to_empty = -ENODATA;
 454                         cache.time_to_empty_avg = -ENODATA;
 455                         cache.time_to_full = -ENODATA;
 456                         cache.charge_full = -ENODATA;
 457                         cache.health = -ENODATA;
 458                 } else {
 459                         cache.capacity = bq27x00_battery_read_rsoc(di);
 460                         if (is_bq27742)
 461                                 cache.time_to_empty =
 462                                         bq27x00_battery_read_time(di,
 463                                                         BQ27x00_REG_TTE);
 464                         else if (!is_bq27425) {
 465                                 cache.energy = bq27x00_battery_read_energy(di);
 466                                 cache.time_to_empty =
 467                                         bq27x00_battery_read_time(di,
 468                                                         BQ27x00_REG_TTE);
 469                                 cache.time_to_empty_avg =
 470                                         bq27x00_battery_read_time(di,
 471                                                         BQ27x00_REG_TTECP);
 472                                 cache.time_to_full =
 473                                         bq27x00_battery_read_time(di,
 474                                                         BQ27x00_REG_TTF);
 475                         }
 476                         cache.charge_full = bq27x00_battery_read_lmd(di);
 477                         cache.health = bq27x00_battery_read_health(di);
 478                 }
 479                 cache.temperature = bq27x00_battery_read_temperature(di);
 480                 if (!is_bq27425)
 481                         cache.cycle_count = bq27x00_battery_read_cyct(di);
 482                 if (is_bq27742)
 483                         cache.power_avg =
 484                                 bq27x00_battery_read_pwr_avg(di,
 485                                                 BQ27742_POWER_AVG);
 486                 else
 487                         cache.power_avg =
 488                                 bq27x00_battery_read_pwr_avg(di,
 489                                                 BQ27x00_POWER_AVG);
 490
 491                 /* We only have to read charge design full once */
 492                 if (di->charge_design_full <= 0)
 493                         di->charge_design_full = bq27x00_battery_read_ilmd(di);
 494         }
 495
 496         if (memcmp(&di->cache, &cache, sizeof(cache)) != 0) {
 497                 di->cache = cache;
 498                 power_supply_changed(&di->bat);
 499         }
 500
 501         di->last_update = jiffies;
 502 }
 503
 504 static void bq27x00_battery_poll(struct work_struct *work)
 505 {
 506         struct bq27x00_device_info *di =
 507                 container_of(work, struct bq27x00_device_info, work.work);
 508
 509         bq27x00_update(di);
 510
 511         if (poll_interval > 0) {
 512                 /* The timer does not have to be accurate. */
 513                 set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
 514                 schedule_delayed_work(&di->work, poll_interval * HZ);
 515         }
 516 }
 517
 518 /*
 519  * Return the battery average current in µA
 520  * Note that current can be negative signed as well
 521  * Or 0 if something fails.
 522  */
 523 static int bq27x00_battery_current(struct bq27x00_device_info *di,
 524         union power_supply_propval *val)
 525 {
 526         int curr;
 527         int flags;
 528
 529         curr = bq27x00_read(di, BQ27x00_REG_AI, false);
 530         if (curr < 0) {
 531                 dev_err(di->dev, "error reading current\n");
 532                 return curr;
 533         }
 534
 535         if (bq27xxx_is_chip_version_higher(di)) {
 536                 /* bq27500 returns signed value */
 537                 val->intval = (int)((s16)curr) * 1000;
 538         } else {
 539                 flags = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
 540                 if (flags & BQ27000_FLAG_CHGS) {
 541                         dev_dbg(di->dev, "negative current!\n");
 542                         curr = -curr;
 543                 }
 544
 545                 val->intval = curr * 3570 / BQ27000_RS;
 546         }
 547
 548         return 0;
 549 }
 550
 551 static int bq27x00_battery_status(struct bq27x00_device_info *di,
 552         union power_supply_propval *val)
 553 {
 554         int status;
 555
 556         if (bq27xxx_is_chip_version_higher(di)) {
 557                 if (di->cache.flags & BQ27500_FLAG_FC)
 558                         status = POWER_SUPPLY_STATUS_FULL;
 559                 else if (di->cache.flags & BQ27500_FLAG_DSC)
 560                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 561                 else
 562                         status = POWER_SUPPLY_STATUS_CHARGING;
 563         } else {
 564                 if (di->cache.flags & BQ27000_FLAG_FC)
 565                         status = POWER_SUPPLY_STATUS_FULL;
 566                 else if (di->cache.flags & BQ27000_FLAG_CHGS)
 567                         status = POWER_SUPPLY_STATUS_CHARGING;
 568                 else if (power_supply_am_i_supplied(&di->bat))
 569                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 570                 else
 571                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 572         }
 573
 574         val->intval = status;
 575
 576         return 0;
 577 }
 578
 579 static int bq27x00_battery_capacity_level(struct bq27x00_device_info *di,
 580         union power_supply_propval *val)
 581 {
 582         int level;
 583
 584         if (bq27xxx_is_chip_version_higher(di)) {
 585                 if (di->cache.flags & BQ27500_FLAG_FC)
 586                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 587                 else if (di->cache.flags & BQ27500_FLAG_SOC1)
 588                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 589                 else if (di->cache.flags & BQ27500_FLAG_SOCF)
 590                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 591                 else
 592                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 593         } else {
 594                 if (di->cache.flags & BQ27000_FLAG_FC)
 595                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 596                 else if (di->cache.flags & BQ27000_FLAG_EDV1)
 597                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 598                 else if (di->cache.flags & BQ27000_FLAG_EDVF)
 599                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 600                 else
 601                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 602         }
 603
 604         val->intval = level;
 605
 606         return 0;
 607 }
 608
 609 /*
 610  * Return the battery Voltage in millivolts
 611  * Or < 0 if something fails.
 612  */
 613 static int bq27x00_battery_voltage(struct bq27x00_device_info *di,
 614         union power_supply_propval *val)
 615 {
 616         int volt;
 617
 618         volt = bq27x00_read(di, BQ27x00_REG_VOLT, false);
 619         if (volt < 0) {
 620                 dev_err(di->dev, "error reading voltage\n");
 621                 return volt;
 622         }
 623
 624         val->intval = volt * 1000;
 625
 626         return 0;
 627 }
 628
 629 static int bq27x00_simple_value(int value,
 630         union power_supply_propval *val)
 631 {
 632         if (value < 0)
 633                 return value;
 634
 635         val->intval = value;
 636
 637         return 0;
 638 }
 639
 640 #define to_bq27x00_device_info(x) container_of((x), \
 641                                 struct bq27x00_device_info, bat);
 642
 643 static int bq27x00_battery_get_property(struct power_supply *psy,
 644                                         enum power_supply_property psp,
 645                                         union power_supply_propval *val)
 646 {
 647         int ret = 0;
 648         struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
 649
 650         mutex_lock(&di->lock);
 651         if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
 652                 cancel_delayed_work_sync(&di->work);
 653                 bq27x00_battery_poll(&di->work.work);
 654         }
 655         mutex_unlock(&di->lock);
 656
 657         if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
 658                 return -ENODEV;
 659
 660         switch (psp) {
 661         case POWER_SUPPLY_PROP_STATUS:
 662                 ret = bq27x00_battery_status(di, val);
 663                 break;
 664         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 665                 ret = bq27x00_battery_voltage(di, val);
 666                 break;
 667         case POWER_SUPPLY_PROP_PRESENT:
 668                 val->intval = di->cache.flags < 0 ? 0 : 1;
 669                 break;
 670         case POWER_SUPPLY_PROP_CURRENT_NOW:
 671                 ret = bq27x00_battery_current(di, val);
 672                 break;
 673         case POWER_SUPPLY_PROP_CAPACITY:
 674                 ret = bq27x00_simple_value(di->cache.capacity, val);
 675                 break;
 676         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 677                 ret = bq27x00_battery_capacity_level(di, val);
 678                 break;
 679         case POWER_SUPPLY_PROP_TEMP:
 680                 ret = bq27x00_simple_value(di->cache.temperature, val);
 681                 if (ret == 0)
 682                         val->intval -= 2731;
 683                 break;
 684         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
 685                 ret = bq27x00_simple_value(di->cache.time_to_empty, val);
 686                 break;
 687         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 688                 ret = bq27x00_simple_value(di->cache.time_to_empty_avg, val);
 689                 break;
 690         case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
 691                 ret = bq27x00_simple_value(di->cache.time_to_full, val);
 692                 break;
 693         case POWER_SUPPLY_PROP_TECHNOLOGY:
 694                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 695                 break;
 696         case POWER_SUPPLY_PROP_CHARGE_NOW:
 697                 ret = bq27x00_simple_value(bq27x00_battery_read_nac(di), val);
 698                 break;
 699         case POWER_SUPPLY_PROP_CHARGE_FULL:
 700                 ret = bq27x00_simple_value(di->cache.charge_full, val);
 701                 break;
 702         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 703                 ret = bq27x00_simple_value(di->charge_design_full, val);
 704                 break;
 705         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 706                 ret = bq27x00_simple_value(di->cache.cycle_count, val);
 707                 break;
 708         case POWER_SUPPLY_PROP_ENERGY_NOW:
 709                 ret = bq27x00_simple_value(di->cache.energy, val);
 710                 break;
 711         case POWER_SUPPLY_PROP_POWER_AVG:
 712                 ret = bq27x00_simple_value(di->cache.power_avg, val);
 713                 break;
 714         case POWER_SUPPLY_PROP_HEALTH:
 715                 ret = bq27x00_simple_value(di->cache.health, val);
 716                 break;
 717         default:
 718                 return -EINVAL;
 719         }
 720
 721         return ret;
 722 }
 723
 724 static void bq27x00_external_power_changed(struct power_supply *psy)
 725 {
 726         struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
 727
 728         cancel_delayed_work_sync(&di->work);
 729         schedule_delayed_work(&di->work, 0);
 730 }
 731
 732 static int bq27x00_powersupply_init(struct bq27x00_device_info *di)
 733 {
 734         int ret;
 735
 736         di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 737         if (di->chip == BQ27425) {
 738                 di->bat.properties = bq27425_battery_props;
 739                 di->bat.num_properties = ARRAY_SIZE(bq27425_battery_props);
 740         } else if (di->chip == BQ27742) {
 741                 di->bat.properties = bq27742_battery_props;
 742                 di->bat.num_properties = ARRAY_SIZE(bq27742_battery_props);
 743         } else {
 744                 di->bat.properties = bq27x00_battery_props;
 745                 di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
 746         }
 747         di->bat.get_property = bq27x00_battery_get_property;
 748         di->bat.external_power_changed = bq27x00_external_power_changed;
 749
 750         INIT_DELAYED_WORK(&di->work, bq27x00_battery_poll);
 751         mutex_init(&di->lock);
 752
 753         ret = power_supply_register(di->dev, &di->bat);
 754         if (ret) {
 755                 dev_err(di->dev, "failed to register battery: %d\n", ret);
 756                 return ret;
 757         }
 758
 759         dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
 760
 761         bq27x00_update(di);
 762
 763         return 0;
 764 }
 765
 766 static void bq27x00_powersupply_unregister(struct bq27x00_device_info *di)
 767 {
 768         /*
 769          * power_supply_unregister call bq27x00_battery_get_property which
 770          * call bq27x00_battery_poll.
 771          * Make sure that bq27x00_battery_poll will not call
 772          * schedule_delayed_work again after unregister (which cause OOPS).
 773          */
 774         poll_interval = 0;
 775
 776         cancel_delayed_work_sync(&di->work);
 777
 778         power_supply_unregister(&di->bat);
 779
 780         mutex_destroy(&di->lock);
 781 }
 782
 783
 784 /* i2c specific code */
 785 #ifdef CONFIG_BATTERY_BQ27X00_I2C
 786
 787 /* If the system has several batteries we need a different name for each
 788  * of them...
 789  */
 790 static DEFINE_IDR(battery_id);
 791 static DEFINE_MUTEX(battery_mutex);
 792
 793 static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
 794 {
 795         struct i2c_client *client = to_i2c_client(di->dev);
 796         struct i2c_msg msg[2];
 797         unsigned char data[2];
 798         int ret;
 799
 800         if (!client->adapter)
 801                 return -ENODEV;
 802
 803         msg[0].addr = client->addr;
 804         msg[0].flags = 0;
 805         msg[0].buf = &reg;
 806         msg[0].len = sizeof(reg);
 807         msg[1].addr = client->addr;
 808         msg[1].flags = I2C_M_RD;
 809         msg[1].buf = data;
 810         if (single)
 811                 msg[1].len = 1;
 812         else
 813                 msg[1].len = 2;
 814
 815         ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
 816         if (ret < 0)
 817                 return ret;
 818
 819         if (!single)
 820                 ret = get_unaligned_le16(data);
 821         else
 822                 ret = data[0];
 823
 824         return ret;
 825 }
 826
 827 static int bq27x00_battery_probe(struct i2c_client *client,
 828                                  const struct i2c_device_id *id)
 829 {
 830         char *name;
 831         struct bq27x00_device_info *di;
 832         int num;
 833         int retval = 0;
 834
 835         /* Get new ID for the new battery device */
 836         mutex_lock(&battery_mutex);
 837         num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
 838         mutex_unlock(&battery_mutex);
 839         if (num < 0)
 840                 return num;
 841
 842         name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num);
 843         if (!name) {
 844                 dev_err(&client->dev, "failed to allocate device name\n");
 845                 retval = -ENOMEM;
 846                 goto batt_failed_1;
 847         }
 848
 849         di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
 850         if (!di) {
 851                 dev_err(&client->dev, "failed to allocate device info data\n");
 852                 retval = -ENOMEM;
 853                 goto batt_failed_2;
 854         }
 855
 856         di->id = num;
 857         di->dev = &client->dev;
 858         di->chip = id->driver_data;
 859         di->bat.name = name;
 860         di->bus.read = &bq27x00_read_i2c;
 861
 862         retval = bq27x00_powersupply_init(di);
 863         if (retval)
 864                 goto batt_failed_2;
 865
 866         i2c_set_clientdata(client, di);
 867
 868         return 0;
 869
 870 batt_failed_2:
 871         kfree(name);
 872 batt_failed_1:
 873         mutex_lock(&battery_mutex);
 874         idr_remove(&battery_id, num);
 875         mutex_unlock(&battery_mutex);
 876
 877         return retval;
 878 }
 879
 880 static int bq27x00_battery_remove(struct i2c_client *client)
 881 {
 882         struct bq27x00_device_info *di = i2c_get_clientdata(client);
 883
 884         bq27x00_powersupply_unregister(di);
 885
 886         kfree(di->bat.name);
 887
 888         mutex_lock(&battery_mutex);
 889         idr_remove(&battery_id, di->id);
 890         mutex_unlock(&battery_mutex);
 891
 892         return 0;
 893 }
 894
 895 static const struct i2c_device_id bq27x00_id[] = {
 896         { "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */
 897         { "bq27500", BQ27500 },
 898         { "bq27425", BQ27425 },
 899         { "bq27742", BQ27742 },
 900         {},
 901 };
 902 MODULE_DEVICE_TABLE(i2c, bq27x00_id);
 903
 904 static struct i2c_driver bq27x00_battery_driver = {
 905         .driver = {
 906                 .name = "bq27x00-battery",
 907         },
 908         .probe = bq27x00_battery_probe,
 909         .remove = bq27x00_battery_remove,
 910         .id_table = bq27x00_id,
 911 };
 912
 913 static inline int bq27x00_battery_i2c_init(void)
 914 {
 915         int ret = i2c_add_driver(&bq27x00_battery_driver);
 916         if (ret)
 917                 printk(KERN_ERR "Unable to register BQ27x00 i2c driver\n");
 918
 919         return ret;
 920 }
 921
 922 static inline void bq27x00_battery_i2c_exit(void)
 923 {
 924         i2c_del_driver(&bq27x00_battery_driver);
 925 }
 926
 927 #else
 928
 929 static inline int bq27x00_battery_i2c_init(void) { return 0; }
 930 static inline void bq27x00_battery_i2c_exit(void) {};
 931
 932 #endif
 933
 934 /* platform specific code */
 935 #ifdef CONFIG_BATTERY_BQ27X00_PLATFORM
 936
 937 static int bq27000_read_platform(struct bq27x00_device_info *di, u8 reg,
 938                         bool single)
 939 {
 940         struct device *dev = di->dev;
 941         struct bq27000_platform_data *pdata = dev->platform_data;
 942         unsigned int timeout = 3;
 943         int upper, lower;
 944         int temp;
 945
 946         if (!single) {
 947                 /* Make sure the value has not changed in between reading the
 948                  * lower and the upper part */
 949                 upper = pdata->read(dev, reg + 1);
 950                 do {
 951                         temp = upper;
 952                         if (upper < 0)
 953                                 return upper;
 954
 955                         lower = pdata->read(dev, reg);
 956                         if (lower < 0)
 957                                 return lower;
 958
 959                         upper = pdata->read(dev, reg + 1);
 960                 } while (temp != upper && --timeout);
 961
 962                 if (timeout == 0)
 963                         return -EIO;
 964
 965                 return (upper << 8) | lower;
 966         }
 967
 968         return pdata->read(dev, reg);
 969 }
 970
 971 static int bq27000_battery_probe(struct platform_device *pdev)
 972 {
 973         struct bq27x00_device_info *di;
 974         struct bq27000_platform_data *pdata = pdev->dev.platform_data;
 975
 976         if (!pdata) {
 977                 dev_err(&pdev->dev, "no platform_data supplied\n");
 978                 return -EINVAL;
 979         }
 980
 981         if (!pdata->read) {
 982                 dev_err(&pdev->dev, "no hdq read callback supplied\n");
 983                 return -EINVAL;
 984         }
 985
 986         di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
 987         if (!di) {
 988                 dev_err(&pdev->dev, "failed to allocate device info data\n");
 989                 return -ENOMEM;
 990         }
 991
 992         platform_set_drvdata(pdev, di);
 993
 994         di->dev = &pdev->dev;
 995         di->chip = BQ27000;
 996
 997         di->bat.name = pdata->name ?: dev_name(&pdev->dev);
 998         di->bus.read = &bq27000_read_platform;
 999
1000         return bq27x00_powersupply_init(di);
1001 }
1002
1003 static int bq27000_battery_remove(struct platform_device *pdev)
1004 {
1005         struct bq27x00_device_info *di = platform_get_drvdata(pdev);
1006
1007         bq27x00_powersupply_unregister(di);
1008
1009         return 0;
1010 }
1011
1012 static struct platform_driver bq27000_battery_driver = {
1013         .probe  = bq27000_battery_probe,
1014         .remove = bq27000_battery_remove,
1015         .driver = {
1016                 .name = "bq27000-battery",
1017                 .owner = THIS_MODULE,
1018         },
1019 };
1020
1021 static inline int bq27x00_battery_platform_init(void)
1022 {
1023         int ret = platform_driver_register(&bq27000_battery_driver);
1024         if (ret)
1025                 printk(KERN_ERR "Unable to register BQ27000 platform driver\n");
1026
1027         return ret;
1028 }
1029
1030 static inline void bq27x00_battery_platform_exit(void)
1031 {
1032         platform_driver_unregister(&bq27000_battery_driver);
1033 }
1034
1035 #else
1036
1037 static inline int bq27x00_battery_platform_init(void) { return 0; }
1038 static inline void bq27x00_battery_platform_exit(void) {};
1039
1040 #endif
1041
1042 /*
1043  * Module stuff
1044  */
1045
1046 static int __init bq27x00_battery_init(void)
1047 {
1048         int ret;
1049
1050         ret = bq27x00_battery_i2c_init();
1051         if (ret)
1052                 return ret;
1053
1054         ret = bq27x00_battery_platform_init();
1055         if (ret)
1056                 bq27x00_battery_i2c_exit();
1057
1058         return ret;
1059 }
1060 module_init(bq27x00_battery_init);
1061
1062 static void __exit bq27x00_battery_exit(void)
1063 {
1064         bq27x00_battery_platform_exit();
1065         bq27x00_battery_i2c_exit();
1066 }
1067 module_exit(bq27x00_battery_exit);
1068
1069 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1070 MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
1071 MODULE_LICENSE("GPL");