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  * 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/bq27x00_battery.h>
  41
  42 #define DRIVER_VERSION                  "1.2.0"
  43
  44 #define BQ27x00_REG_TEMP                0x06
  45 #define BQ27x00_REG_VOLT                0x08
  46 #define BQ27x00_REG_AI                  0x14
  47 #define BQ27x00_REG_FLAGS               0x0A
  48 #define BQ27x00_REG_TTE                 0x16
  49 #define BQ27x00_REG_TTF                 0x18
  50 #define BQ27x00_REG_TTECP               0x26
  51 #define BQ27x00_REG_NAC                 0x0C /* Nominal available capacity */
  52 #define BQ27x00_REG_LMD                 0x12 /* Last measured discharge */
  53 #define BQ27x00_REG_CYCT                0x2A /* Cycle count total */
  54 #define BQ27x00_REG_AE                  0x22 /* Available energy */
  55 #define BQ27x00_POWER_AVG               0x24
  56
  57 #define BQ27000_REG_RSOC                0x0B /* Relative State-of-Charge */
  58 #define BQ27000_REG_ILMD                0x76 /* Initial last measured discharge */
  59 #define BQ27000_FLAG_EDVF               BIT(0) /* Final End-of-Discharge-Voltage flag */
  60 #define BQ27000_FLAG_EDV1               BIT(1) /* First End-of-Discharge-Voltage flag */
  61 #define BQ27000_FLAG_CI                 BIT(4) /* Capacity Inaccurate flag */
  62 #define BQ27000_FLAG_FC                 BIT(5)
  63 #define BQ27000_FLAG_CHGS               BIT(7) /* Charge state flag */
  64
  65 #define BQ27500_REG_SOC                 0x2C
  66 #define BQ27500_REG_DCAP                0x3C /* Design capacity */
  67 #define BQ27500_FLAG_DSC                BIT(0)
  68 #define BQ27500_FLAG_SOCF               BIT(1) /* State-of-Charge threshold final */
  69 #define BQ27500_FLAG_SOC1               BIT(2) /* State-of-Charge threshold 1 */
  70 #define BQ27500_FLAG_FC                 BIT(9)
  71 #define BQ27500_FLAG_OTC                BIT(15)
  72
  73 #define BQ27742_POWER_AVG               0x76
  74
  75 #define BQ27510_REG_SOC                 0x20
  76 #define BQ27510_REG_DCAP                0x2E /* Design capacity */
  77 #define BQ27510_REG_CYCT                0x1E /* Cycle count total */
  78
  79 /* bq27425 register addresses are same as bq27x00 addresses minus 4 */
  80 #define BQ27425_REG_OFFSET              0x04
  81 #define BQ27425_REG_SOC         (0x1C + BQ27425_REG_OFFSET)
  82 #define BQ27425_REG_DCAP                (0x3C + BQ27425_REG_OFFSET)
  83
  84 #define BQ27000_RS                      20 /* Resistor sense */
  85 #define BQ27x00_POWER_CONSTANT          (256 * 29200 / 1000)
  86
  87 struct bq27x00_device_info;
  88 struct bq27x00_access_methods {
  89         int (*read)(struct bq27x00_device_info *di, u8 reg, bool single);
  90 };
  91
  92 enum bq27x00_chip { BQ27000, BQ27500, BQ27425, BQ27742, BQ27510};
  93
  94 struct bq27x00_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 bq27x00_device_info {
 109         struct device           *dev;
 110         int                     id;
 111         enum bq27x00_chip       chip;
 112
 113         struct bq27x00_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 bq27x00_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 };
 146
 147 static enum power_supply_property bq27425_battery_props[] = {
 148         POWER_SUPPLY_PROP_STATUS,
 149         POWER_SUPPLY_PROP_PRESENT,
 150         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 151         POWER_SUPPLY_PROP_CURRENT_NOW,
 152         POWER_SUPPLY_PROP_CAPACITY,
 153         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 154         POWER_SUPPLY_PROP_TEMP,
 155         POWER_SUPPLY_PROP_TECHNOLOGY,
 156         POWER_SUPPLY_PROP_CHARGE_FULL,
 157         POWER_SUPPLY_PROP_CHARGE_NOW,
 158         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 159 };
 160
 161 static enum power_supply_property bq27742_battery_props[] = {
 162         POWER_SUPPLY_PROP_STATUS,
 163         POWER_SUPPLY_PROP_PRESENT,
 164         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 165         POWER_SUPPLY_PROP_CURRENT_NOW,
 166         POWER_SUPPLY_PROP_CAPACITY,
 167         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 168         POWER_SUPPLY_PROP_TEMP,
 169         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 170         POWER_SUPPLY_PROP_TECHNOLOGY,
 171         POWER_SUPPLY_PROP_CHARGE_FULL,
 172         POWER_SUPPLY_PROP_CHARGE_NOW,
 173         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 174         POWER_SUPPLY_PROP_CYCLE_COUNT,
 175         POWER_SUPPLY_PROP_POWER_AVG,
 176         POWER_SUPPLY_PROP_HEALTH,
 177 };
 178
 179 static enum power_supply_property bq27510_battery_props[] = {
 180         POWER_SUPPLY_PROP_STATUS,
 181         POWER_SUPPLY_PROP_PRESENT,
 182         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 183         POWER_SUPPLY_PROP_CURRENT_NOW,
 184         POWER_SUPPLY_PROP_CAPACITY,
 185         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 186         POWER_SUPPLY_PROP_TEMP,
 187         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 188         POWER_SUPPLY_PROP_TECHNOLOGY,
 189         POWER_SUPPLY_PROP_CHARGE_FULL,
 190         POWER_SUPPLY_PROP_CHARGE_NOW,
 191         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 192         POWER_SUPPLY_PROP_CYCLE_COUNT,
 193         POWER_SUPPLY_PROP_POWER_AVG,
 194         POWER_SUPPLY_PROP_HEALTH,
 195 };
 196
 197 static unsigned int poll_interval = 360;
 198 module_param(poll_interval, uint, 0644);
 199 MODULE_PARM_DESC(poll_interval, "battery poll interval in seconds - " \
 200                                 "0 disables polling");
 201
 202 /*
 203  * Common code for BQ27x00 devices
 204  */
 205
 206 static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg,
 207                 bool single)
 208 {
 209         if (di->chip == BQ27425)
 210                 return di->bus.read(di, reg - BQ27425_REG_OFFSET, single);
 211         return di->bus.read(di, reg, single);
 212 }
 213
 214 /*
 215  * Higher versions of the chip like BQ27425 and BQ27500
 216  * differ from BQ27000 and BQ27200 in calculation of certain
 217  * parameters. Hence we need to check for the chip type.
 218  */
 219 static bool bq27xxx_is_chip_version_higher(struct bq27x00_device_info *di)
 220 {
 221         if (di->chip == BQ27425 || di->chip == BQ27500 || di->chip == BQ27742
 222             || di->chip == BQ27510)
 223                 return true;
 224         return false;
 225 }
 226
 227 /*
 228  * Return the battery Relative State-of-Charge
 229  * Or < 0 if something fails.
 230  */
 231 static int bq27x00_battery_read_rsoc(struct bq27x00_device_info *di)
 232 {
 233         int rsoc;
 234
 235         if (di->chip == BQ27500 || di->chip == BQ27742)
 236                 rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
 237         else if (di->chip == BQ27510)
 238                 rsoc = bq27x00_read(di, BQ27510_REG_SOC, false);
 239         else if (di->chip == BQ27425)
 240                 rsoc = bq27x00_read(di, BQ27425_REG_SOC, false);
 241         else
 242                 rsoc = bq27x00_read(di, BQ27000_REG_RSOC, true);
 243
 244         if (rsoc < 0)
 245                 dev_dbg(di->dev, "error reading relative State-of-Charge\n");
 246
 247         return rsoc;
 248 }
 249
 250 /*
 251  * Return a battery charge value in µAh
 252  * Or < 0 if something fails.
 253  */
 254 static int bq27x00_battery_read_charge(struct bq27x00_device_info *di, u8 reg)
 255 {
 256         int charge;
 257
 258         charge = bq27x00_read(di, reg, false);
 259         if (charge < 0) {
 260                 dev_dbg(di->dev, "error reading charge register %02x: %d\n",
 261                         reg, charge);
 262                 return charge;
 263         }
 264
 265         if (bq27xxx_is_chip_version_higher(di))
 266                 charge *= 1000;
 267         else
 268                 charge = charge * 3570 / BQ27000_RS;
 269
 270         return charge;
 271 }
 272
 273 /*
 274  * Return the battery Nominal available capaciy in µAh
 275  * Or < 0 if something fails.
 276  */
 277 static inline int bq27x00_battery_read_nac(struct bq27x00_device_info *di)
 278 {
 279         int flags;
 280         bool is_bq27500 = di->chip == BQ27500;
 281         bool is_bq27742 = di->chip == BQ27742;
 282         bool is_higher = bq27xxx_is_chip_version_higher(di);
 283         bool flags_1b = !(is_bq27500 || is_bq27742);
 284
 285         flags = bq27x00_read(di, BQ27x00_REG_FLAGS, flags_1b);
 286         if (flags >= 0 && !is_higher && (flags & BQ27000_FLAG_CI))
 287                 return -ENODATA;
 288
 289         return bq27x00_battery_read_charge(di, BQ27x00_REG_NAC);
 290 }
 291
 292 /*
 293  * Return the battery Last measured discharge in µAh
 294  * Or < 0 if something fails.
 295  */
 296 static inline int bq27x00_battery_read_lmd(struct bq27x00_device_info *di)
 297 {
 298         return bq27x00_battery_read_charge(di, BQ27x00_REG_LMD);
 299 }
 300
 301 /*
 302  * Return the battery Initial last measured discharge in µAh
 303  * Or < 0 if something fails.
 304  */
 305 static int bq27x00_battery_read_ilmd(struct bq27x00_device_info *di)
 306 {
 307         int ilmd;
 308
 309         if (bq27xxx_is_chip_version_higher(di)) {
 310                 if (di->chip == BQ27425)
 311                         ilmd = bq27x00_read(di, BQ27425_REG_DCAP, false);
 312                 else if (di->chip == BQ27510)
 313                         ilmd = bq27x00_read(di, BQ27510_REG_DCAP, false);
 314                 else
 315                         ilmd = bq27x00_read(di, BQ27500_REG_DCAP, false);
 316         } else
 317                 ilmd = bq27x00_read(di, BQ27000_REG_ILMD, true);
 318
 319         if (ilmd < 0) {
 320                 dev_dbg(di->dev, "error reading initial last measured discharge\n");
 321                 return ilmd;
 322         }
 323
 324         if (bq27xxx_is_chip_version_higher(di))
 325                 ilmd *= 1000;
 326         else
 327                 ilmd = ilmd * 256 * 3570 / BQ27000_RS;
 328
 329         return ilmd;
 330 }
 331
 332 /*
 333  * Return the battery Available energy in µWh
 334  * Or < 0 if something fails.
 335  */
 336 static int bq27x00_battery_read_energy(struct bq27x00_device_info *di)
 337 {
 338         int ae;
 339
 340         ae = bq27x00_read(di, BQ27x00_REG_AE, false);
 341         if (ae < 0) {
 342                 dev_dbg(di->dev, "error reading available energy\n");
 343                 return ae;
 344         }
 345
 346         if (di->chip == BQ27500)
 347                 ae *= 1000;
 348         else
 349                 ae = ae * 29200 / BQ27000_RS;
 350
 351         return ae;
 352 }
 353
 354 /*
 355  * Return the battery temperature in tenths of degree Kelvin
 356  * Or < 0 if something fails.
 357  */
 358 static int bq27x00_battery_read_temperature(struct bq27x00_device_info *di)
 359 {
 360         int temp;
 361
 362         temp = bq27x00_read(di, BQ27x00_REG_TEMP, false);
 363         if (temp < 0) {
 364                 dev_err(di->dev, "error reading temperature\n");
 365                 return temp;
 366         }
 367
 368         if (!bq27xxx_is_chip_version_higher(di))
 369                 temp = 5 * temp / 2;
 370
 371         return temp;
 372 }
 373
 374 /*
 375  * Return the battery Cycle count total
 376  * Or < 0 if something fails.
 377  */
 378 static int bq27x00_battery_read_cyct(struct bq27x00_device_info *di)
 379 {
 380         int cyct;
 381
 382         if (di->chip == BQ27510)
 383                 cyct = bq27x00_read(di, BQ27510_REG_CYCT, false);
 384         else
 385                 cyct = bq27x00_read(di, BQ27x00_REG_CYCT, false);
 386         if (cyct < 0)
 387                 dev_err(di->dev, "error reading cycle count total\n");
 388
 389         return cyct;
 390 }
 391
 392 /*
 393  * Read a time register.
 394  * Return < 0 if something fails.
 395  */
 396 static int bq27x00_battery_read_time(struct bq27x00_device_info *di, u8 reg)
 397 {
 398         int tval;
 399
 400         tval = bq27x00_read(di, reg, false);
 401         if (tval < 0) {
 402                 dev_dbg(di->dev, "error reading time register %02x: %d\n",
 403                         reg, tval);
 404                 return tval;
 405         }
 406
 407         if (tval == 65535)
 408                 return -ENODATA;
 409
 410         return tval * 60;
 411 }
 412
 413 /*
 414  * Read a power avg register.
 415  * Return < 0 if something fails.
 416  */
 417 static int bq27x00_battery_read_pwr_avg(struct bq27x00_device_info *di, u8 reg)
 418 {
 419         int tval;
 420
 421         tval = bq27x00_read(di, reg, false);
 422         if (tval < 0) {
 423                 dev_err(di->dev, "error reading power avg rgister  %02x: %d\n",
 424                         reg, tval);
 425                 return tval;
 426         }
 427
 428         if (di->chip == BQ27500)
 429                 return tval;
 430         else
 431                 return (tval * BQ27x00_POWER_CONSTANT) / BQ27000_RS;
 432 }
 433
 434 /*
 435  * Read flag register.
 436  * Return < 0 if something fails.
 437  */
 438 static int bq27x00_battery_read_health(struct bq27x00_device_info *di)
 439 {
 440         int tval;
 441
 442         tval = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
 443         if (tval < 0) {
 444                 dev_err(di->dev, "error reading flag register:%d\n", tval);
 445                 return tval;
 446         }
 447
 448         if ((di->chip == BQ27500)) {
 449                 if (tval & BQ27500_FLAG_SOCF)
 450                         tval = POWER_SUPPLY_HEALTH_DEAD;
 451                 else if (tval & BQ27500_FLAG_OTC)
 452                         tval = POWER_SUPPLY_HEALTH_OVERHEAT;
 453                 else
 454                         tval = POWER_SUPPLY_HEALTH_GOOD;
 455                 return tval;
 456         } else if (di->chip == BQ27510) {
 457                 if (tval & BQ27500_FLAG_OTC)
 458                         return POWER_SUPPLY_HEALTH_OVERHEAT;
 459                 return POWER_SUPPLY_HEALTH_GOOD;
 460         } else {
 461                 if (tval & BQ27000_FLAG_EDV1)
 462                         tval = POWER_SUPPLY_HEALTH_DEAD;
 463                 else
 464                         tval = POWER_SUPPLY_HEALTH_GOOD;
 465                 return tval;
 466         }
 467
 468         return -1;
 469 }
 470
 471 static void bq27x00_update(struct bq27x00_device_info *di)
 472 {
 473         struct bq27x00_reg_cache cache = {0, };
 474         bool is_bq27500 = di->chip == BQ27500;
 475         bool is_bq27510 = di->chip == BQ27510;
 476         bool is_bq27425 = di->chip == BQ27425;
 477         bool is_bq27742 = di->chip == BQ27742;
 478         bool flags_1b = !(is_bq27500 || is_bq27742);
 479
 480         cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, flags_1b);
 481         if ((cache.flags & 0xff) == 0xff)
 482                 /* read error */
 483                 cache.flags = -1;
 484         if (cache.flags >= 0) {
 485                 if (!is_bq27500 && !is_bq27425 && !is_bq27742 && !is_bq27510
 486                                 && (cache.flags & BQ27000_FLAG_CI)) {
 487                         dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
 488                         cache.capacity = -ENODATA;
 489                         cache.energy = -ENODATA;
 490                         cache.time_to_empty = -ENODATA;
 491                         cache.time_to_empty_avg = -ENODATA;
 492                         cache.time_to_full = -ENODATA;
 493                         cache.charge_full = -ENODATA;
 494                         cache.health = -ENODATA;
 495                 } else {
 496                         cache.capacity = bq27x00_battery_read_rsoc(di);
 497                         if (is_bq27742 || is_bq27510)
 498                                 cache.time_to_empty =
 499                                         bq27x00_battery_read_time(di,
 500                                                         BQ27x00_REG_TTE);
 501                         else if (!is_bq27425) {
 502                                 cache.energy = bq27x00_battery_read_energy(di);
 503                                 cache.time_to_empty =
 504                                         bq27x00_battery_read_time(di,
 505                                                         BQ27x00_REG_TTE);
 506                                 cache.time_to_empty_avg =
 507                                         bq27x00_battery_read_time(di,
 508                                                         BQ27x00_REG_TTECP);
 509                                 cache.time_to_full =
 510                                         bq27x00_battery_read_time(di,
 511                                                         BQ27x00_REG_TTF);
 512                         }
 513                         cache.charge_full = bq27x00_battery_read_lmd(di);
 514                         cache.health = bq27x00_battery_read_health(di);
 515                 }
 516                 cache.temperature = bq27x00_battery_read_temperature(di);
 517                 if (!is_bq27425)
 518                         cache.cycle_count = bq27x00_battery_read_cyct(di);
 519                 if (is_bq27742)
 520                         cache.power_avg =
 521                                 bq27x00_battery_read_pwr_avg(di,
 522                                                 BQ27742_POWER_AVG);
 523                 else
 524                         cache.power_avg =
 525                                 bq27x00_battery_read_pwr_avg(di,
 526                                                 BQ27x00_POWER_AVG);
 527
 528                 /* We only have to read charge design full once */
 529                 if (di->charge_design_full <= 0)
 530                         di->charge_design_full = bq27x00_battery_read_ilmd(di);
 531         }
 532
 533         if (di->cache.capacity != cache.capacity)
 534                 power_supply_changed(di->bat);
 535
 536         if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
 537                 di->cache = cache;
 538
 539         di->last_update = jiffies;
 540 }
 541
 542 static void bq27x00_battery_poll(struct work_struct *work)
 543 {
 544         struct bq27x00_device_info *di =
 545                 container_of(work, struct bq27x00_device_info, work.work);
 546
 547         bq27x00_update(di);
 548
 549         if (poll_interval > 0) {
 550                 /* The timer does not have to be accurate. */
 551                 set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
 552                 schedule_delayed_work(&di->work, poll_interval * HZ);
 553         }
 554 }
 555
 556 /*
 557  * Return the battery average current in µA
 558  * Note that current can be negative signed as well
 559  * Or 0 if something fails.
 560  */
 561 static int bq27x00_battery_current(struct bq27x00_device_info *di,
 562         union power_supply_propval *val)
 563 {
 564         int curr;
 565         int flags;
 566
 567         curr = bq27x00_read(di, BQ27x00_REG_AI, false);
 568         if (curr < 0) {
 569                 dev_err(di->dev, "error reading current\n");
 570                 return curr;
 571         }
 572
 573         if (bq27xxx_is_chip_version_higher(di)) {
 574                 /* bq27500 returns signed value */
 575                 val->intval = (int)((s16)curr) * 1000;
 576         } else {
 577                 flags = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
 578                 if (flags & BQ27000_FLAG_CHGS) {
 579                         dev_dbg(di->dev, "negative current!\n");
 580                         curr = -curr;
 581                 }
 582
 583                 val->intval = curr * 3570 / BQ27000_RS;
 584         }
 585
 586         return 0;
 587 }
 588
 589 static int bq27x00_battery_status(struct bq27x00_device_info *di,
 590         union power_supply_propval *val)
 591 {
 592         int status;
 593
 594         if (bq27xxx_is_chip_version_higher(di)) {
 595                 if (di->cache.flags & BQ27500_FLAG_FC)
 596                         status = POWER_SUPPLY_STATUS_FULL;
 597                 else if (di->cache.flags & BQ27500_FLAG_DSC)
 598                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 599                 else
 600                         status = POWER_SUPPLY_STATUS_CHARGING;
 601         } else {
 602                 if (di->cache.flags & BQ27000_FLAG_FC)
 603                         status = POWER_SUPPLY_STATUS_FULL;
 604                 else if (di->cache.flags & BQ27000_FLAG_CHGS)
 605                         status = POWER_SUPPLY_STATUS_CHARGING;
 606                 else if (power_supply_am_i_supplied(di->bat))
 607                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 608                 else
 609                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 610         }
 611
 612         val->intval = status;
 613
 614         return 0;
 615 }
 616
 617 static int bq27x00_battery_capacity_level(struct bq27x00_device_info *di,
 618         union power_supply_propval *val)
 619 {
 620         int level;
 621
 622         if (bq27xxx_is_chip_version_higher(di)) {
 623                 if (di->cache.flags & BQ27500_FLAG_FC)
 624                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 625                 else if (di->cache.flags & BQ27500_FLAG_SOC1)
 626                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 627                 else if (di->cache.flags & BQ27500_FLAG_SOCF)
 628                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 629                 else
 630                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 631         } else {
 632                 if (di->cache.flags & BQ27000_FLAG_FC)
 633                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 634                 else if (di->cache.flags & BQ27000_FLAG_EDV1)
 635                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 636                 else if (di->cache.flags & BQ27000_FLAG_EDVF)
 637                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 638                 else
 639                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 640         }
 641
 642         val->intval = level;
 643
 644         return 0;
 645 }
 646
 647 /*
 648  * Return the battery Voltage in millivolts
 649  * Or < 0 if something fails.
 650  */
 651 static int bq27x00_battery_voltage(struct bq27x00_device_info *di,
 652         union power_supply_propval *val)
 653 {
 654         int volt;
 655
 656         volt = bq27x00_read(di, BQ27x00_REG_VOLT, false);
 657         if (volt < 0) {
 658                 dev_err(di->dev, "error reading voltage\n");
 659                 return volt;
 660         }
 661
 662         val->intval = volt * 1000;
 663
 664         return 0;
 665 }
 666
 667 static int bq27x00_simple_value(int value,
 668         union power_supply_propval *val)
 669 {
 670         if (value < 0)
 671                 return value;
 672
 673         val->intval = value;
 674
 675         return 0;
 676 }
 677
 678 static int bq27x00_battery_get_property(struct power_supply *psy,
 679                                         enum power_supply_property psp,
 680                                         union power_supply_propval *val)
 681 {
 682         int ret = 0;
 683         struct bq27x00_device_info *di = power_supply_get_drvdata(psy);
 684
 685         mutex_lock(&di->lock);
 686         if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
 687                 cancel_delayed_work_sync(&di->work);
 688                 bq27x00_battery_poll(&di->work.work);
 689         }
 690         mutex_unlock(&di->lock);
 691
 692         if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
 693                 return -ENODEV;
 694
 695         switch (psp) {
 696         case POWER_SUPPLY_PROP_STATUS:
 697                 ret = bq27x00_battery_status(di, val);
 698                 break;
 699         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 700                 ret = bq27x00_battery_voltage(di, val);
 701                 break;
 702         case POWER_SUPPLY_PROP_PRESENT:
 703                 val->intval = di->cache.flags < 0 ? 0 : 1;
 704                 break;
 705         case POWER_SUPPLY_PROP_CURRENT_NOW:
 706                 ret = bq27x00_battery_current(di, val);
 707                 break;
 708         case POWER_SUPPLY_PROP_CAPACITY:
 709                 ret = bq27x00_simple_value(di->cache.capacity, val);
 710                 break;
 711         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 712                 ret = bq27x00_battery_capacity_level(di, val);
 713                 break;
 714         case POWER_SUPPLY_PROP_TEMP:
 715                 ret = bq27x00_simple_value(di->cache.temperature, val);
 716                 if (ret == 0)
 717                         val->intval -= 2731;
 718                 break;
 719         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
 720                 ret = bq27x00_simple_value(di->cache.time_to_empty, val);
 721                 break;
 722         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 723                 ret = bq27x00_simple_value(di->cache.time_to_empty_avg, val);
 724                 break;
 725         case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
 726                 ret = bq27x00_simple_value(di->cache.time_to_full, val);
 727                 break;
 728         case POWER_SUPPLY_PROP_TECHNOLOGY:
 729                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 730                 break;
 731         case POWER_SUPPLY_PROP_CHARGE_NOW:
 732                 ret = bq27x00_simple_value(bq27x00_battery_read_nac(di), val);
 733                 break;
 734         case POWER_SUPPLY_PROP_CHARGE_FULL:
 735                 ret = bq27x00_simple_value(di->cache.charge_full, val);
 736                 break;
 737         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 738                 ret = bq27x00_simple_value(di->charge_design_full, val);
 739                 break;
 740         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 741                 ret = bq27x00_simple_value(di->cache.cycle_count, val);
 742                 break;
 743         case POWER_SUPPLY_PROP_ENERGY_NOW:
 744                 ret = bq27x00_simple_value(di->cache.energy, val);
 745                 break;
 746         case POWER_SUPPLY_PROP_POWER_AVG:
 747                 ret = bq27x00_simple_value(di->cache.power_avg, val);
 748                 break;
 749         case POWER_SUPPLY_PROP_HEALTH:
 750                 ret = bq27x00_simple_value(di->cache.health, val);
 751                 break;
 752         default:
 753                 return -EINVAL;
 754         }
 755
 756         return ret;
 757 }
 758
 759 static void bq27x00_external_power_changed(struct power_supply *psy)
 760 {
 761         struct bq27x00_device_info *di = power_supply_get_drvdata(psy);
 762
 763         cancel_delayed_work_sync(&di->work);
 764         schedule_delayed_work(&di->work, 0);
 765 }
 766
 767 static int bq27x00_powersupply_init(struct bq27x00_device_info *di,
 768                                     const char *name)
 769 {
 770         int ret;
 771         struct power_supply_desc *psy_desc;
 772         struct power_supply_config psy_cfg = { .drv_data = di, };
 773
 774         psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
 775         if (!psy_desc)
 776                 return -ENOMEM;
 777
 778         psy_desc->name = name;
 779         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 780         if (di->chip == BQ27425) {
 781                 psy_desc->properties = bq27425_battery_props;
 782                 psy_desc->num_properties = ARRAY_SIZE(bq27425_battery_props);
 783         } else if (di->chip == BQ27742) {
 784                 psy_desc->properties = bq27742_battery_props;
 785                 psy_desc->num_properties = ARRAY_SIZE(bq27742_battery_props);
 786         } else if (di->chip == BQ27510) {
 787                 psy_desc->properties = bq27510_battery_props;
 788                 psy_desc->num_properties = ARRAY_SIZE(bq27510_battery_props);
 789         } else {
 790                 psy_desc->properties = bq27x00_battery_props;
 791                 psy_desc->num_properties = ARRAY_SIZE(bq27x00_battery_props);
 792         }
 793         psy_desc->get_property = bq27x00_battery_get_property;
 794         psy_desc->external_power_changed = bq27x00_external_power_changed;
 795
 796         INIT_DELAYED_WORK(&di->work, bq27x00_battery_poll);
 797         mutex_init(&di->lock);
 798
 799         di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
 800         if (IS_ERR(di->bat)) {
 801                 ret = PTR_ERR(di->bat);
 802                 dev_err(di->dev, "failed to register battery: %d\n", ret);
 803                 return ret;
 804         }
 805
 806         dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
 807
 808         bq27x00_update(di);
 809
 810         return 0;
 811 }
 812
 813 static void bq27x00_powersupply_unregister(struct bq27x00_device_info *di)
 814 {
 815         /*
 816          * power_supply_unregister call bq27x00_battery_get_property which
 817          * call bq27x00_battery_poll.
 818          * Make sure that bq27x00_battery_poll will not call
 819          * schedule_delayed_work again after unregister (which cause OOPS).
 820          */
 821         poll_interval = 0;
 822
 823         cancel_delayed_work_sync(&di->work);
 824
 825         power_supply_unregister(di->bat);
 826
 827         mutex_destroy(&di->lock);
 828 }
 829
 830
 831 /* i2c specific code */
 832 #ifdef CONFIG_BATTERY_BQ27X00_I2C
 833
 834 /* If the system has several batteries we need a different name for each
 835  * of them...
 836  */
 837 static DEFINE_IDR(battery_id);
 838 static DEFINE_MUTEX(battery_mutex);
 839
 840 static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
 841 {
 842         struct i2c_client *client = to_i2c_client(di->dev);
 843         struct i2c_msg msg[2];
 844         unsigned char data[2];
 845         int ret;
 846
 847         if (!client->adapter)
 848                 return -ENODEV;
 849
 850         msg[0].addr = client->addr;
 851         msg[0].flags = 0;
 852         msg[0].buf = &reg;
 853         msg[0].len = sizeof(reg);
 854         msg[1].addr = client->addr;
 855         msg[1].flags = I2C_M_RD;
 856         msg[1].buf = data;
 857         if (single)
 858                 msg[1].len = 1;
 859         else
 860                 msg[1].len = 2;
 861
 862         ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
 863         if (ret < 0)
 864                 return ret;
 865
 866         if (!single)
 867                 ret = get_unaligned_le16(data);
 868         else
 869                 ret = data[0];
 870
 871         return ret;
 872 }
 873
 874 static int bq27x00_battery_probe(struct i2c_client *client,
 875                                  const struct i2c_device_id *id)
 876 {
 877         char *name;
 878         struct bq27x00_device_info *di;
 879         int num;
 880         int retval = 0;
 881
 882         /* Get new ID for the new battery device */
 883         mutex_lock(&battery_mutex);
 884         num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
 885         mutex_unlock(&battery_mutex);
 886         if (num < 0)
 887                 return num;
 888
 889         name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
 890         if (!name) {
 891                 dev_err(&client->dev, "failed to allocate device name\n");
 892                 retval = -ENOMEM;
 893                 goto batt_failed;
 894         }
 895
 896         di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
 897         if (!di) {
 898                 dev_err(&client->dev, "failed to allocate device info data\n");
 899                 retval = -ENOMEM;
 900                 goto batt_failed;
 901         }
 902
 903         di->id = num;
 904         di->dev = &client->dev;
 905         di->chip = id->driver_data;
 906         di->bus.read = &bq27x00_read_i2c;
 907
 908         retval = bq27x00_powersupply_init(di, name);
 909         if (retval)
 910                 goto batt_failed;
 911
 912         i2c_set_clientdata(client, di);
 913
 914         return 0;
 915
 916 batt_failed:
 917         mutex_lock(&battery_mutex);
 918         idr_remove(&battery_id, num);
 919         mutex_unlock(&battery_mutex);
 920
 921         return retval;
 922 }
 923
 924 static int bq27x00_battery_remove(struct i2c_client *client)
 925 {
 926         struct bq27x00_device_info *di = i2c_get_clientdata(client);
 927
 928         bq27x00_powersupply_unregister(di);
 929
 930         mutex_lock(&battery_mutex);
 931         idr_remove(&battery_id, di->id);
 932         mutex_unlock(&battery_mutex);
 933
 934         return 0;
 935 }
 936
 937 static const struct i2c_device_id bq27x00_id[] = {
 938         { "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */
 939         { "bq27500", BQ27500 },
 940         { "bq27425", BQ27425 },
 941         { "bq27742", BQ27742 },
 942         { "bq27510", BQ27510 },
 943         {},
 944 };
 945 MODULE_DEVICE_TABLE(i2c, bq27x00_id);
 946
 947 static struct i2c_driver bq27x00_battery_driver = {
 948         .driver = {
 949                 .name = "bq27x00-battery",
 950         },
 951         .probe = bq27x00_battery_probe,
 952         .remove = bq27x00_battery_remove,
 953         .id_table = bq27x00_id,
 954 };
 955
 956 static inline int bq27x00_battery_i2c_init(void)
 957 {
 958         int ret = i2c_add_driver(&bq27x00_battery_driver);
 959         if (ret)
 960                 printk(KERN_ERR "Unable to register BQ27x00 i2c driver\n");
 961
 962         return ret;
 963 }
 964
 965 static inline void bq27x00_battery_i2c_exit(void)
 966 {
 967         i2c_del_driver(&bq27x00_battery_driver);
 968 }
 969
 970 #else
 971
 972 static inline int bq27x00_battery_i2c_init(void) { return 0; }
 973 static inline void bq27x00_battery_i2c_exit(void) {};
 974
 975 #endif
 976
 977 /* platform specific code */
 978 #ifdef CONFIG_BATTERY_BQ27X00_PLATFORM
 979
 980 static int bq27000_read_platform(struct bq27x00_device_info *di, u8 reg,
 981                         bool single)
 982 {
 983         struct device *dev = di->dev;
 984         struct bq27000_platform_data *pdata = dev->platform_data;
 985         unsigned int timeout = 3;
 986         int upper, lower;
 987         int temp;
 988
 989         if (!single) {
 990                 /* Make sure the value has not changed in between reading the
 991                  * lower and the upper part */
 992                 upper = pdata->read(dev, reg + 1);
 993                 do {
 994                         temp = upper;
 995                         if (upper < 0)
 996                                 return upper;
 997
 998                         lower = pdata->read(dev, reg);
 999                         if (lower < 0)
1000                                 return lower;
1001
1002                         upper = pdata->read(dev, reg + 1);
1003                 } while (temp != upper && --timeout);
1004
1005                 if (timeout == 0)
1006                         return -EIO;
1007
1008                 return (upper << 8) | lower;
1009         }
1010
1011         return pdata->read(dev, reg);
1012 }
1013
1014 static int bq27000_battery_probe(struct platform_device *pdev)
1015 {
1016         struct bq27x00_device_info *di;
1017         struct bq27000_platform_data *pdata = pdev->dev.platform_data;
1018         const char *name;
1019
1020         if (!pdata) {
1021                 dev_err(&pdev->dev, "no platform_data supplied\n");
1022                 return -EINVAL;
1023         }
1024
1025         if (!pdata->read) {
1026                 dev_err(&pdev->dev, "no hdq read callback supplied\n");
1027                 return -EINVAL;
1028         }
1029
1030         di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1031         if (!di) {
1032                 dev_err(&pdev->dev, "failed to allocate device info data\n");
1033                 return -ENOMEM;
1034         }
1035
1036         platform_set_drvdata(pdev, di);
1037
1038         di->dev = &pdev->dev;
1039         di->chip = BQ27000;
1040
1041         name = pdata->name ?: dev_name(&pdev->dev);
1042         di->bus.read = &bq27000_read_platform;
1043
1044         return bq27x00_powersupply_init(di, name);
1045 }
1046
1047 static int bq27000_battery_remove(struct platform_device *pdev)
1048 {
1049         struct bq27x00_device_info *di = platform_get_drvdata(pdev);
1050
1051         bq27x00_powersupply_unregister(di);
1052
1053         return 0;
1054 }
1055
1056 static struct platform_driver bq27000_battery_driver = {
1057         .probe  = bq27000_battery_probe,
1058         .remove = bq27000_battery_remove,
1059         .driver = {
1060                 .name = "bq27000-battery",
1061         },
1062 };
1063
1064 static inline int bq27x00_battery_platform_init(void)
1065 {
1066         int ret = platform_driver_register(&bq27000_battery_driver);
1067         if (ret)
1068                 printk(KERN_ERR "Unable to register BQ27000 platform driver\n");
1069
1070         return ret;
1071 }
1072
1073 static inline void bq27x00_battery_platform_exit(void)
1074 {
1075         platform_driver_unregister(&bq27000_battery_driver);
1076 }
1077
1078 #else
1079
1080 static inline int bq27x00_battery_platform_init(void) { return 0; }
1081 static inline void bq27x00_battery_platform_exit(void) {};
1082
1083 #endif
1084
1085 /*
1086  * Module stuff
1087  */
1088
1089 static int __init bq27x00_battery_init(void)
1090 {
1091         int ret;
1092
1093         ret = bq27x00_battery_i2c_init();
1094         if (ret)
1095                 return ret;
1096
1097         ret = bq27x00_battery_platform_init();
1098         if (ret)
1099                 bq27x00_battery_i2c_exit();
1100
1101         return ret;
1102 }
1103 module_init(bq27x00_battery_init);
1104
1105 static void __exit bq27x00_battery_exit(void)
1106 {
1107         bq27x00_battery_platform_exit();
1108         bq27x00_battery_i2c_exit();
1109 }
1110 module_exit(bq27x00_battery_exit);
1111
1112 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1113 MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
1114 MODULE_LICENSE("GPL");