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