drivers/power/supply/bq27xxx_battery.c

   1 /*
   2  * BQ27xxx battery driver
   3  *
   4  * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
   5  * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
   6  * Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
   7  * Copyright (C) 2011 Pali Rohár <pali.rohar@gmail.com>
   8  *
   9  * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
  10  *
  11  * This package is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  *
  15  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  17  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  18  *
  19  * Datasheets:
  20  * http://www.ti.com/product/bq27000
  21  * http://www.ti.com/product/bq27200
  22  * http://www.ti.com/product/bq27010
  23  * http://www.ti.com/product/bq27210
  24  * http://www.ti.com/product/bq27500
  25  * http://www.ti.com/product/bq27510-g3
  26  * http://www.ti.com/product/bq27520-g4
  27  * http://www.ti.com/product/bq27530-g1
  28  * http://www.ti.com/product/bq27531-g1
  29  * http://www.ti.com/product/bq27541-g1
  30  * http://www.ti.com/product/bq27542-g1
  31  * http://www.ti.com/product/bq27546-g1
  32  * http://www.ti.com/product/bq27742-g1
  33  * http://www.ti.com/product/bq27545-g1
  34  * http://www.ti.com/product/bq27421-g1
  35  * http://www.ti.com/product/bq27425-g1
  36  * http://www.ti.com/product/bq27411-g1
  37  * http://www.ti.com/product/bq27621-g1
  38  */
  39
  40 #include <linux/device.h>
  41 #include <linux/module.h>
  42 #include <linux/mutex.h>
  43 #include <linux/param.h>
  44 #include <linux/jiffies.h>
  45 #include <linux/workqueue.h>
  46 #include <linux/delay.h>
  47 #include <linux/platform_device.h>
  48 #include <linux/power_supply.h>
  49 #include <linux/slab.h>
  50 #include <linux/of.h>
  51
  52 #include <linux/power/bq27xxx_battery.h>
  53
  54 #define DRIVER_VERSION          "1.2.0"
  55
  56 #define BQ27XXX_MANUFACTURER    "Texas Instruments"
  57
  58 /* BQ27XXX Flags */
  59 #define BQ27XXX_FLAG_DSC        BIT(0)
  60 #define BQ27XXX_FLAG_SOCF       BIT(1) /* State-of-Charge threshold final */
  61 #define BQ27XXX_FLAG_SOC1       BIT(2) /* State-of-Charge threshold 1 */
  62 #define BQ27XXX_FLAG_FC         BIT(9)
  63 #define BQ27XXX_FLAG_OTD        BIT(14)
  64 #define BQ27XXX_FLAG_OTC        BIT(15)
  65 #define BQ27XXX_FLAG_UT         BIT(14)
  66 #define BQ27XXX_FLAG_OT         BIT(15)
  67
  68 /* BQ27000 has different layout for Flags register */
  69 #define BQ27000_FLAG_EDVF       BIT(0) /* Final End-of-Discharge-Voltage flag */
  70 #define BQ27000_FLAG_EDV1       BIT(1) /* First End-of-Discharge-Voltage flag */
  71 #define BQ27000_FLAG_CI         BIT(4) /* Capacity Inaccurate flag */
  72 #define BQ27000_FLAG_FC         BIT(5)
  73 #define BQ27000_FLAG_CHGS       BIT(7) /* Charge state flag */
  74
  75 #define BQ27XXX_RS                      (20) /* Resistor sense mOhm */
  76 #define BQ27XXX_POWER_CONSTANT          (29200) /* 29.2 µV^2 * 1000 */
  77 #define BQ27XXX_CURRENT_CONSTANT        (3570) /* 3.57 µV * 1000 */
  78
  79 #define INVALID_REG_ADDR        0xff
  80
  81 /*
  82  * bq27xxx_reg_index - Register names
  83  *
  84  * These are indexes into a device's register mapping array.
  85  */
  86
  87 enum bq27xxx_reg_index {
  88         BQ27XXX_REG_CTRL = 0,   /* Control */
  89         BQ27XXX_REG_TEMP,       /* Temperature */
  90         BQ27XXX_REG_INT_TEMP,   /* Internal Temperature */
  91         BQ27XXX_REG_VOLT,       /* Voltage */
  92         BQ27XXX_REG_AI,         /* Average Current */
  93         BQ27XXX_REG_FLAGS,      /* Flags */
  94         BQ27XXX_REG_TTE,        /* Time-to-Empty */
  95         BQ27XXX_REG_TTF,        /* Time-to-Full */
  96         BQ27XXX_REG_TTES,       /* Time-to-Empty Standby */
  97         BQ27XXX_REG_TTECP,      /* Time-to-Empty at Constant Power */
  98         BQ27XXX_REG_NAC,        /* Nominal Available Capacity */
  99         BQ27XXX_REG_FCC,        /* Full Charge Capacity */
 100         BQ27XXX_REG_CYCT,       /* Cycle Count */
 101         BQ27XXX_REG_AE,         /* Available Energy */
 102         BQ27XXX_REG_SOC,        /* State-of-Charge */
 103         BQ27XXX_REG_DCAP,       /* Design Capacity */
 104         BQ27XXX_REG_AP,         /* Average Power */
 105         BQ27XXX_REG_MAX,        /* sentinel */
 106 };
 107
 108 /* Register mappings */
 109 static u8 bq27xxx_regs[][BQ27XXX_REG_MAX] = {
 110         [BQ27000] = {
 111                 [BQ27XXX_REG_CTRL] = 0x00,
 112                 [BQ27XXX_REG_TEMP] = 0x06,
 113                 [BQ27XXX_REG_INT_TEMP] = INVALID_REG_ADDR,
 114                 [BQ27XXX_REG_VOLT] = 0x08,
 115                 [BQ27XXX_REG_AI] = 0x14,
 116                 [BQ27XXX_REG_FLAGS] = 0x0a,
 117                 [BQ27XXX_REG_TTE] = 0x16,
 118                 [BQ27XXX_REG_TTF] = 0x18,
 119                 [BQ27XXX_REG_TTES] = 0x1c,
 120                 [BQ27XXX_REG_TTECP] = 0x26,
 121                 [BQ27XXX_REG_NAC] = 0x0c,
 122                 [BQ27XXX_REG_FCC] = 0x12,
 123                 [BQ27XXX_REG_CYCT] = 0x2a,
 124                 [BQ27XXX_REG_AE] = 0x22,
 125                 [BQ27XXX_REG_SOC] = 0x0b,
 126                 [BQ27XXX_REG_DCAP] = 0x76,
 127                 [BQ27XXX_REG_AP] = 0x24,
 128         },
 129         [BQ27010] = {
 130                 [BQ27XXX_REG_CTRL] = 0x00,
 131                 [BQ27XXX_REG_TEMP] = 0x06,
 132                 [BQ27XXX_REG_INT_TEMP] = INVALID_REG_ADDR,
 133                 [BQ27XXX_REG_VOLT] = 0x08,
 134                 [BQ27XXX_REG_AI] = 0x14,
 135                 [BQ27XXX_REG_FLAGS] = 0x0a,
 136                 [BQ27XXX_REG_TTE] = 0x16,
 137                 [BQ27XXX_REG_TTF] = 0x18,
 138                 [BQ27XXX_REG_TTES] = 0x1c,
 139                 [BQ27XXX_REG_TTECP] = 0x26,
 140                 [BQ27XXX_REG_NAC] = 0x0c,
 141                 [BQ27XXX_REG_FCC] = 0x12,
 142                 [BQ27XXX_REG_CYCT] = 0x2a,
 143                 [BQ27XXX_REG_AE] = INVALID_REG_ADDR,
 144                 [BQ27XXX_REG_SOC] = 0x0b,
 145                 [BQ27XXX_REG_DCAP] = 0x76,
 146                 [BQ27XXX_REG_AP] = INVALID_REG_ADDR,
 147         },
 148         [BQ27500] = {
 149                 [BQ27XXX_REG_CTRL] = 0x00,
 150                 [BQ27XXX_REG_TEMP] = 0x06,
 151                 [BQ27XXX_REG_INT_TEMP] = 0x28,
 152                 [BQ27XXX_REG_VOLT] = 0x08,
 153                 [BQ27XXX_REG_AI] = 0x14,
 154                 [BQ27XXX_REG_FLAGS] = 0x0a,
 155                 [BQ27XXX_REG_TTE] = 0x16,
 156                 [BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
 157                 [BQ27XXX_REG_TTES] = 0x1a,
 158                 [BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 159                 [BQ27XXX_REG_NAC] = 0x0c,
 160                 [BQ27XXX_REG_FCC] = 0x12,
 161                 [BQ27XXX_REG_CYCT] = 0x2a,
 162                 [BQ27XXX_REG_AE] = INVALID_REG_ADDR,
 163                 [BQ27XXX_REG_SOC] = 0x2c,
 164                 [BQ27XXX_REG_DCAP] = 0x3c,
 165                 [BQ27XXX_REG_AP] = INVALID_REG_ADDR,
 166         },
 167         [BQ27530] = {
 168                 [BQ27XXX_REG_CTRL] = 0x00,
 169                 [BQ27XXX_REG_TEMP] = 0x06,
 170                 [BQ27XXX_REG_INT_TEMP] = 0x32,
 171                 [BQ27XXX_REG_VOLT] = 0x08,
 172                 [BQ27XXX_REG_AI] = 0x14,
 173                 [BQ27XXX_REG_FLAGS] = 0x0a,
 174                 [BQ27XXX_REG_TTE] = 0x16,
 175                 [BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
 176                 [BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 177                 [BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 178                 [BQ27XXX_REG_NAC] = 0x0c,
 179                 [BQ27XXX_REG_FCC] = 0x12,
 180                 [BQ27XXX_REG_CYCT] = 0x2a,
 181                 [BQ27XXX_REG_AE] = INVALID_REG_ADDR,
 182                 [BQ27XXX_REG_SOC] = 0x2c,
 183                 [BQ27XXX_REG_DCAP] = INVALID_REG_ADDR,
 184                 [BQ27XXX_REG_AP] = 0x24,
 185         },
 186         [BQ27541] = {
 187                 [BQ27XXX_REG_CTRL] = 0x00,
 188                 [BQ27XXX_REG_TEMP] = 0x06,
 189                 [BQ27XXX_REG_INT_TEMP] = 0x28,
 190                 [BQ27XXX_REG_VOLT] = 0x08,
 191                 [BQ27XXX_REG_AI] = 0x14,
 192                 [BQ27XXX_REG_FLAGS] = 0x0a,
 193                 [BQ27XXX_REG_TTE] = 0x16,
 194                 [BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
 195                 [BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 196                 [BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 197                 [BQ27XXX_REG_NAC] = 0x0c,
 198                 [BQ27XXX_REG_FCC] = 0x12,
 199                 [BQ27XXX_REG_CYCT] = 0x2a,
 200                 [BQ27XXX_REG_AE] = INVALID_REG_ADDR,
 201                 [BQ27XXX_REG_SOC] = 0x2c,
 202                 [BQ27XXX_REG_DCAP] = 0x3c,
 203                 [BQ27XXX_REG_AP] = 0x24,
 204         },
 205         [BQ27545] = {
 206                 [BQ27XXX_REG_CTRL] = 0x00,
 207                 [BQ27XXX_REG_TEMP] = 0x06,
 208                 [BQ27XXX_REG_INT_TEMP] = 0x28,
 209                 [BQ27XXX_REG_VOLT] = 0x08,
 210                 [BQ27XXX_REG_AI] = 0x14,
 211                 [BQ27XXX_REG_FLAGS] = 0x0a,
 212                 [BQ27XXX_REG_TTE] = 0x16,
 213                 [BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
 214                 [BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 215                 [BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 216                 [BQ27XXX_REG_NAC] = 0x0c,
 217                 [BQ27XXX_REG_FCC] = 0x12,
 218                 [BQ27XXX_REG_CYCT] = 0x2a,
 219                 [BQ27XXX_REG_AE] = INVALID_REG_ADDR,
 220                 [BQ27XXX_REG_SOC] = 0x2c,
 221                 [BQ27XXX_REG_DCAP] = INVALID_REG_ADDR,
 222                 [BQ27XXX_REG_AP] = 0x24,
 223         },
 224         [BQ27421] = {
 225                 [BQ27XXX_REG_CTRL] = 0x00,
 226                 [BQ27XXX_REG_TEMP] = 0x02,
 227                 [BQ27XXX_REG_INT_TEMP] = 0x1e,
 228                 [BQ27XXX_REG_VOLT] = 0x04,
 229                 [BQ27XXX_REG_AI] = 0x10,
 230                 [BQ27XXX_REG_FLAGS] = 0x06,
 231                 [BQ27XXX_REG_TTE] = INVALID_REG_ADDR,
 232                 [BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
 233                 [BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 234                 [BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 235                 [BQ27XXX_REG_NAC] = 0x08,
 236                 [BQ27XXX_REG_FCC] = 0x0e,
 237                 [BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
 238                 [BQ27XXX_REG_AE] = INVALID_REG_ADDR,
 239                 [BQ27XXX_REG_SOC] = 0x1c,
 240                 [BQ27XXX_REG_DCAP] = 0x3c,
 241                 [BQ27XXX_REG_AP] = 0x18,
 242         },
 243 };
 244
 245 static enum power_supply_property bq27000_battery_props[] = {
 246         POWER_SUPPLY_PROP_STATUS,
 247         POWER_SUPPLY_PROP_PRESENT,
 248         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 249         POWER_SUPPLY_PROP_CURRENT_NOW,
 250         POWER_SUPPLY_PROP_CAPACITY,
 251         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 252         POWER_SUPPLY_PROP_TEMP,
 253         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 254         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 255         POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 256         POWER_SUPPLY_PROP_TECHNOLOGY,
 257         POWER_SUPPLY_PROP_CHARGE_FULL,
 258         POWER_SUPPLY_PROP_CHARGE_NOW,
 259         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 260         POWER_SUPPLY_PROP_CYCLE_COUNT,
 261         POWER_SUPPLY_PROP_ENERGY_NOW,
 262         POWER_SUPPLY_PROP_POWER_AVG,
 263         POWER_SUPPLY_PROP_HEALTH,
 264         POWER_SUPPLY_PROP_MANUFACTURER,
 265 };
 266
 267 static enum power_supply_property bq27010_battery_props[] = {
 268         POWER_SUPPLY_PROP_STATUS,
 269         POWER_SUPPLY_PROP_PRESENT,
 270         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 271         POWER_SUPPLY_PROP_CURRENT_NOW,
 272         POWER_SUPPLY_PROP_CAPACITY,
 273         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 274         POWER_SUPPLY_PROP_TEMP,
 275         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 276         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 277         POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 278         POWER_SUPPLY_PROP_TECHNOLOGY,
 279         POWER_SUPPLY_PROP_CHARGE_FULL,
 280         POWER_SUPPLY_PROP_CHARGE_NOW,
 281         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 282         POWER_SUPPLY_PROP_CYCLE_COUNT,
 283         POWER_SUPPLY_PROP_HEALTH,
 284         POWER_SUPPLY_PROP_MANUFACTURER,
 285 };
 286
 287 static enum power_supply_property bq27500_battery_props[] = {
 288         POWER_SUPPLY_PROP_STATUS,
 289         POWER_SUPPLY_PROP_PRESENT,
 290         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 291         POWER_SUPPLY_PROP_CURRENT_NOW,
 292         POWER_SUPPLY_PROP_CAPACITY,
 293         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 294         POWER_SUPPLY_PROP_TEMP,
 295         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 296         POWER_SUPPLY_PROP_TECHNOLOGY,
 297         POWER_SUPPLY_PROP_CHARGE_FULL,
 298         POWER_SUPPLY_PROP_CHARGE_NOW,
 299         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 300         POWER_SUPPLY_PROP_CYCLE_COUNT,
 301         POWER_SUPPLY_PROP_HEALTH,
 302         POWER_SUPPLY_PROP_MANUFACTURER,
 303 };
 304
 305 static enum power_supply_property bq27530_battery_props[] = {
 306         POWER_SUPPLY_PROP_STATUS,
 307         POWER_SUPPLY_PROP_PRESENT,
 308         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 309         POWER_SUPPLY_PROP_CURRENT_NOW,
 310         POWER_SUPPLY_PROP_CAPACITY,
 311         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 312         POWER_SUPPLY_PROP_TEMP,
 313         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 314         POWER_SUPPLY_PROP_TECHNOLOGY,
 315         POWER_SUPPLY_PROP_CHARGE_FULL,
 316         POWER_SUPPLY_PROP_CHARGE_NOW,
 317         POWER_SUPPLY_PROP_POWER_AVG,
 318         POWER_SUPPLY_PROP_HEALTH,
 319         POWER_SUPPLY_PROP_CYCLE_COUNT,
 320         POWER_SUPPLY_PROP_MANUFACTURER,
 321 };
 322
 323 static enum power_supply_property bq27541_battery_props[] = {
 324         POWER_SUPPLY_PROP_STATUS,
 325         POWER_SUPPLY_PROP_PRESENT,
 326         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 327         POWER_SUPPLY_PROP_CURRENT_NOW,
 328         POWER_SUPPLY_PROP_CAPACITY,
 329         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 330         POWER_SUPPLY_PROP_TEMP,
 331         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 332         POWER_SUPPLY_PROP_TECHNOLOGY,
 333         POWER_SUPPLY_PROP_CHARGE_FULL,
 334         POWER_SUPPLY_PROP_CHARGE_NOW,
 335         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 336         POWER_SUPPLY_PROP_CYCLE_COUNT,
 337         POWER_SUPPLY_PROP_POWER_AVG,
 338         POWER_SUPPLY_PROP_HEALTH,
 339         POWER_SUPPLY_PROP_MANUFACTURER,
 340 };
 341
 342 static enum power_supply_property bq27545_battery_props[] = {
 343         POWER_SUPPLY_PROP_STATUS,
 344         POWER_SUPPLY_PROP_PRESENT,
 345         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 346         POWER_SUPPLY_PROP_CURRENT_NOW,
 347         POWER_SUPPLY_PROP_CAPACITY,
 348         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 349         POWER_SUPPLY_PROP_TEMP,
 350         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 351         POWER_SUPPLY_PROP_TECHNOLOGY,
 352         POWER_SUPPLY_PROP_CHARGE_FULL,
 353         POWER_SUPPLY_PROP_CHARGE_NOW,
 354         POWER_SUPPLY_PROP_HEALTH,
 355         POWER_SUPPLY_PROP_CYCLE_COUNT,
 356         POWER_SUPPLY_PROP_POWER_AVG,
 357         POWER_SUPPLY_PROP_MANUFACTURER,
 358 };
 359
 360 static enum power_supply_property bq27421_battery_props[] = {
 361         POWER_SUPPLY_PROP_STATUS,
 362         POWER_SUPPLY_PROP_PRESENT,
 363         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 364         POWER_SUPPLY_PROP_CURRENT_NOW,
 365         POWER_SUPPLY_PROP_CAPACITY,
 366         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 367         POWER_SUPPLY_PROP_TEMP,
 368         POWER_SUPPLY_PROP_TECHNOLOGY,
 369         POWER_SUPPLY_PROP_CHARGE_FULL,
 370         POWER_SUPPLY_PROP_CHARGE_NOW,
 371         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 372         POWER_SUPPLY_PROP_MANUFACTURER,
 373 };
 374
 375 #define BQ27XXX_PROP(_id, _prop)                \
 376         [_id] = {                               \
 377                 .props = _prop,                 \
 378                 .size = ARRAY_SIZE(_prop),      \
 379         }
 380
 381 static struct {
 382         enum power_supply_property *props;
 383         size_t size;
 384 } bq27xxx_battery_props[] = {
 385         BQ27XXX_PROP(BQ27000, bq27000_battery_props),
 386         BQ27XXX_PROP(BQ27010, bq27010_battery_props),
 387         BQ27XXX_PROP(BQ27500, bq27500_battery_props),
 388         BQ27XXX_PROP(BQ27530, bq27530_battery_props),
 389         BQ27XXX_PROP(BQ27541, bq27541_battery_props),
 390         BQ27XXX_PROP(BQ27545, bq27545_battery_props),
 391         BQ27XXX_PROP(BQ27421, bq27421_battery_props),
 392 };
 393
 394 static DEFINE_MUTEX(bq27xxx_list_lock);
 395 static LIST_HEAD(bq27xxx_battery_devices);
 396
 397 static int poll_interval_param_set(const char *val, const struct kernel_param *kp)
 398 {
 399         struct bq27xxx_device_info *di;
 400         int ret;
 401
 402         ret = param_set_uint(val, kp);
 403         if (ret < 0)
 404                 return ret;
 405
 406         mutex_lock(&bq27xxx_list_lock);
 407         list_for_each_entry(di, &bq27xxx_battery_devices, list) {
 408                 cancel_delayed_work_sync(&di->work);
 409                 schedule_delayed_work(&di->work, 0);
 410         }
 411         mutex_unlock(&bq27xxx_list_lock);
 412
 413         return ret;
 414 }
 415
 416 static const struct kernel_param_ops param_ops_poll_interval = {
 417         .get = param_get_uint,
 418         .set = poll_interval_param_set,
 419 };
 420
 421 static unsigned int poll_interval = 360;
 422 module_param_cb(poll_interval, &param_ops_poll_interval, &poll_interval, 0644);
 423 MODULE_PARM_DESC(poll_interval,
 424                  "battery poll interval in seconds - 0 disables polling");
 425
 426 /*
 427  * Common code for BQ27xxx devices
 428  */
 429
 430 static inline int bq27xxx_read(struct bq27xxx_device_info *di, int reg_index,
 431                                bool single)
 432 {
 433         /* Reports EINVAL for invalid/missing registers */
 434         if (!di || di->regs[reg_index] == INVALID_REG_ADDR)
 435                 return -EINVAL;
 436
 437         return di->bus.read(di, di->regs[reg_index], single);
 438 }
 439
 440 /*
 441  * Return the battery State-of-Charge
 442  * Or < 0 if something fails.
 443  */
 444 static int bq27xxx_battery_read_soc(struct bq27xxx_device_info *di)
 445 {
 446         int soc;
 447
 448         if (di->chip == BQ27000 || di->chip == BQ27010)
 449                 soc = bq27xxx_read(di, BQ27XXX_REG_SOC, true);
 450         else
 451                 soc = bq27xxx_read(di, BQ27XXX_REG_SOC, false);
 452
 453         if (soc < 0)
 454                 dev_dbg(di->dev, "error reading State-of-Charge\n");
 455
 456         return soc;
 457 }
 458
 459 /*
 460  * Return a battery charge value in µAh
 461  * Or < 0 if something fails.
 462  */
 463 static int bq27xxx_battery_read_charge(struct bq27xxx_device_info *di, u8 reg)
 464 {
 465         int charge;
 466
 467         charge = bq27xxx_read(di, reg, false);
 468         if (charge < 0) {
 469                 dev_dbg(di->dev, "error reading charge register %02x: %d\n",
 470                         reg, charge);
 471                 return charge;
 472         }
 473
 474         if (di->chip == BQ27000 || di->chip == BQ27010)
 475                 charge *= BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
 476         else
 477                 charge *= 1000;
 478
 479         return charge;
 480 }
 481
 482 /*
 483  * Return the battery Nominal available capacity in µAh
 484  * Or < 0 if something fails.
 485  */
 486 static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
 487 {
 488         int flags;
 489
 490         if (di->chip == BQ27000 || di->chip == BQ27010) {
 491                 flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
 492                 if (flags >= 0 && (flags & BQ27000_FLAG_CI))
 493                         return -ENODATA;
 494         }
 495
 496         return bq27xxx_battery_read_charge(di, BQ27XXX_REG_NAC);
 497 }
 498
 499 /*
 500  * Return the battery Full Charge Capacity in µAh
 501  * Or < 0 if something fails.
 502  */
 503 static inline int bq27xxx_battery_read_fcc(struct bq27xxx_device_info *di)
 504 {
 505         return bq27xxx_battery_read_charge(di, BQ27XXX_REG_FCC);
 506 }
 507
 508 /*
 509  * Return the Design Capacity in µAh
 510  * Or < 0 if something fails.
 511  */
 512 static int bq27xxx_battery_read_dcap(struct bq27xxx_device_info *di)
 513 {
 514         int dcap;
 515
 516         if (di->chip == BQ27000 || di->chip == BQ27010)
 517                 dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, true);
 518         else
 519                 dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, false);
 520
 521         if (dcap < 0) {
 522                 dev_dbg(di->dev, "error reading initial last measured discharge\n");
 523                 return dcap;
 524         }
 525
 526         if (di->chip == BQ27000 || di->chip == BQ27010)
 527                 dcap = (dcap << 8) * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
 528         else
 529                 dcap *= 1000;
 530
 531         return dcap;
 532 }
 533
 534 /*
 535  * Return the battery Available energy in µWh
 536  * Or < 0 if something fails.
 537  */
 538 static int bq27xxx_battery_read_energy(struct bq27xxx_device_info *di)
 539 {
 540         int ae;
 541
 542         ae = bq27xxx_read(di, BQ27XXX_REG_AE, false);
 543         if (ae < 0) {
 544                 dev_dbg(di->dev, "error reading available energy\n");
 545                 return ae;
 546         }
 547
 548         if (di->chip == BQ27000 || di->chip == BQ27010)
 549                 ae *= BQ27XXX_POWER_CONSTANT / BQ27XXX_RS;
 550         else
 551                 ae *= 1000;
 552
 553         return ae;
 554 }
 555
 556 /*
 557  * Return the battery temperature in tenths of degree Kelvin
 558  * Or < 0 if something fails.
 559  */
 560 static int bq27xxx_battery_read_temperature(struct bq27xxx_device_info *di)
 561 {
 562         int temp;
 563
 564         temp = bq27xxx_read(di, BQ27XXX_REG_TEMP, false);
 565         if (temp < 0) {
 566                 dev_err(di->dev, "error reading temperature\n");
 567                 return temp;
 568         }
 569
 570         if (di->chip == BQ27000 || di->chip == BQ27010)
 571                 temp = 5 * temp / 2;
 572
 573         return temp;
 574 }
 575
 576 /*
 577  * Return the battery Cycle count total
 578  * Or < 0 if something fails.
 579  */
 580 static int bq27xxx_battery_read_cyct(struct bq27xxx_device_info *di)
 581 {
 582         int cyct;
 583
 584         cyct = bq27xxx_read(di, BQ27XXX_REG_CYCT, false);
 585         if (cyct < 0)
 586                 dev_err(di->dev, "error reading cycle count total\n");
 587
 588         return cyct;
 589 }
 590
 591 /*
 592  * Read a time register.
 593  * Return < 0 if something fails.
 594  */
 595 static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg)
 596 {
 597         int tval;
 598
 599         tval = bq27xxx_read(di, reg, false);
 600         if (tval < 0) {
 601                 dev_dbg(di->dev, "error reading time register %02x: %d\n",
 602                         reg, tval);
 603                 return tval;
 604         }
 605
 606         if (tval == 65535)
 607                 return -ENODATA;
 608
 609         return tval * 60;
 610 }
 611
 612 /*
 613  * Read an average power register.
 614  * Return < 0 if something fails.
 615  */
 616 static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di)
 617 {
 618         int tval;
 619
 620         tval = bq27xxx_read(di, BQ27XXX_REG_AP, false);
 621         if (tval < 0) {
 622                 dev_err(di->dev, "error reading average power register  %02x: %d\n",
 623                         BQ27XXX_REG_AP, tval);
 624                 return tval;
 625         }
 626
 627         if (di->chip == BQ27000 || di->chip == BQ27010)
 628                 return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
 629         else
 630                 return tval;
 631 }
 632
 633 /*
 634  * Returns true if a battery over temperature condition is detected
 635  */
 636 static bool bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
 637 {
 638         if (di->chip == BQ27500 || di->chip == BQ27541 || di->chip == BQ27545)
 639                 return flags & (BQ27XXX_FLAG_OTC | BQ27XXX_FLAG_OTD);
 640         if (di->chip == BQ27530 || di->chip == BQ27421)
 641                 return flags & BQ27XXX_FLAG_OT;
 642
 643         return false;
 644 }
 645
 646 /*
 647  * Returns true if a battery under temperature condition is detected
 648  */
 649 static bool bq27xxx_battery_undertemp(struct bq27xxx_device_info *di, u16 flags)
 650 {
 651         if (di->chip == BQ27530 || di->chip == BQ27421)
 652                 return flags & BQ27XXX_FLAG_UT;
 653
 654         return false;
 655 }
 656
 657 /*
 658  * Returns true if a low state of charge condition is detected
 659  */
 660 static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
 661 {
 662         if (di->chip == BQ27000 || di->chip == BQ27010)
 663                 return flags & (BQ27000_FLAG_EDV1 | BQ27000_FLAG_EDVF);
 664         else
 665                 return flags & (BQ27XXX_FLAG_SOC1 | BQ27XXX_FLAG_SOCF);
 666 }
 667
 668 /*
 669  * Read flag register.
 670  * Return < 0 if something fails.
 671  */
 672 static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
 673 {
 674         int flags;
 675         bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
 676
 677         flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
 678         if (flags < 0) {
 679                 dev_err(di->dev, "error reading flag register:%d\n", flags);
 680                 return flags;
 681         }
 682
 683         /* Unlikely but important to return first */
 684         if (unlikely(bq27xxx_battery_overtemp(di, flags)))
 685                 return POWER_SUPPLY_HEALTH_OVERHEAT;
 686         if (unlikely(bq27xxx_battery_undertemp(di, flags)))
 687                 return POWER_SUPPLY_HEALTH_COLD;
 688         if (unlikely(bq27xxx_battery_dead(di, flags)))
 689                 return POWER_SUPPLY_HEALTH_DEAD;
 690
 691         return POWER_SUPPLY_HEALTH_GOOD;
 692 }
 693
 694 void bq27xxx_battery_update(struct bq27xxx_device_info *di)
 695 {
 696         struct bq27xxx_reg_cache cache = {0, };
 697         bool has_ci_flag = di->chip == BQ27000 || di->chip == BQ27010;
 698         bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
 699
 700         cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
 701         if ((cache.flags & 0xff) == 0xff)
 702                 cache.flags = -1; /* read error */
 703         if (cache.flags >= 0) {
 704                 cache.temperature = bq27xxx_battery_read_temperature(di);
 705                 if (has_ci_flag && (cache.flags & BQ27000_FLAG_CI)) {
 706                         dev_info_once(di->dev, "battery is not calibrated! ignoring capacity values\n");
 707                         cache.capacity = -ENODATA;
 708                         cache.energy = -ENODATA;
 709                         cache.time_to_empty = -ENODATA;
 710                         cache.time_to_empty_avg = -ENODATA;
 711                         cache.time_to_full = -ENODATA;
 712                         cache.charge_full = -ENODATA;
 713                         cache.health = -ENODATA;
 714                 } else {
 715                         if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
 716                                 cache.time_to_empty = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
 717                         if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
 718                                 cache.time_to_empty_avg = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
 719                         if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
 720                                 cache.time_to_full = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
 721                         cache.charge_full = bq27xxx_battery_read_fcc(di);
 722                         cache.capacity = bq27xxx_battery_read_soc(di);
 723                         if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
 724                                 cache.energy = bq27xxx_battery_read_energy(di);
 725                         cache.health = bq27xxx_battery_read_health(di);
 726                 }
 727                 if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
 728                         cache.cycle_count = bq27xxx_battery_read_cyct(di);
 729                 if (di->regs[BQ27XXX_REG_AP] != INVALID_REG_ADDR)
 730                         cache.power_avg = bq27xxx_battery_read_pwr_avg(di);
 731
 732                 /* We only have to read charge design full once */
 733                 if (di->charge_design_full <= 0)
 734                         di->charge_design_full = bq27xxx_battery_read_dcap(di);
 735         }
 736
 737         if (di->cache.capacity != cache.capacity)
 738                 power_supply_changed(di->bat);
 739
 740         if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
 741                 di->cache = cache;
 742
 743         di->last_update = jiffies;
 744 }
 745 EXPORT_SYMBOL_GPL(bq27xxx_battery_update);
 746
 747 static void bq27xxx_battery_poll(struct work_struct *work)
 748 {
 749         struct bq27xxx_device_info *di =
 750                         container_of(work, struct bq27xxx_device_info,
 751                                      work.work);
 752
 753         bq27xxx_battery_update(di);
 754
 755         if (poll_interval > 0)
 756                 schedule_delayed_work(&di->work, poll_interval * HZ);
 757 }
 758
 759 /*
 760  * Return the battery average current in µA
 761  * Note that current can be negative signed as well
 762  * Or 0 if something fails.
 763  */
 764 static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
 765                                    union power_supply_propval *val)
 766 {
 767         int curr;
 768         int flags;
 769
 770         curr = bq27xxx_read(di, BQ27XXX_REG_AI, false);
 771         if (curr < 0) {
 772                 dev_err(di->dev, "error reading current\n");
 773                 return curr;
 774         }
 775
 776         if (di->chip == BQ27000 || di->chip == BQ27010) {
 777                 flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
 778                 if (flags & BQ27000_FLAG_CHGS) {
 779                         dev_dbg(di->dev, "negative current!\n");
 780                         curr = -curr;
 781                 }
 782
 783                 val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
 784         } else {
 785                 /* Other gauges return signed value */
 786                 val->intval = (int)((s16)curr) * 1000;
 787         }
 788
 789         return 0;
 790 }
 791
 792 static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
 793                                   union power_supply_propval *val)
 794 {
 795         int status;
 796
 797         if (di->chip == BQ27000 || di->chip == BQ27010) {
 798                 if (di->cache.flags & BQ27000_FLAG_FC)
 799                         status = POWER_SUPPLY_STATUS_FULL;
 800                 else if (di->cache.flags & BQ27000_FLAG_CHGS)
 801                         status = POWER_SUPPLY_STATUS_CHARGING;
 802                 else if (power_supply_am_i_supplied(di->bat))
 803                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 804                 else
 805                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 806         } else {
 807                 if (di->cache.flags & BQ27XXX_FLAG_FC)
 808                         status = POWER_SUPPLY_STATUS_FULL;
 809                 else if (di->cache.flags & BQ27XXX_FLAG_DSC)
 810                         status = POWER_SUPPLY_STATUS_DISCHARGING;
 811                 else
 812                         status = POWER_SUPPLY_STATUS_CHARGING;
 813         }
 814
 815         val->intval = status;
 816
 817         return 0;
 818 }
 819
 820 static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
 821                                           union power_supply_propval *val)
 822 {
 823         int level;
 824
 825         if (di->chip == BQ27000 || di->chip == BQ27010) {
 826                 if (di->cache.flags & BQ27000_FLAG_FC)
 827                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 828                 else if (di->cache.flags & BQ27000_FLAG_EDV1)
 829                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 830                 else if (di->cache.flags & BQ27000_FLAG_EDVF)
 831                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 832                 else
 833                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 834         } else {
 835                 if (di->cache.flags & BQ27XXX_FLAG_FC)
 836                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 837                 else if (di->cache.flags & BQ27XXX_FLAG_SOC1)
 838                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 839                 else if (di->cache.flags & BQ27XXX_FLAG_SOCF)
 840                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 841                 else
 842                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 843         }
 844
 845         val->intval = level;
 846
 847         return 0;
 848 }
 849
 850 /*
 851  * Return the battery Voltage in millivolts
 852  * Or < 0 if something fails.
 853  */
 854 static int bq27xxx_battery_voltage(struct bq27xxx_device_info *di,
 855                                    union power_supply_propval *val)
 856 {
 857         int volt;
 858
 859         volt = bq27xxx_read(di, BQ27XXX_REG_VOLT, false);
 860         if (volt < 0) {
 861                 dev_err(di->dev, "error reading voltage\n");
 862                 return volt;
 863         }
 864
 865         val->intval = volt * 1000;
 866
 867         return 0;
 868 }
 869
 870 static int bq27xxx_simple_value(int value,
 871                                 union power_supply_propval *val)
 872 {
 873         if (value < 0)
 874                 return value;
 875
 876         val->intval = value;
 877
 878         return 0;
 879 }
 880
 881 static int bq27xxx_battery_get_property(struct power_supply *psy,
 882                                         enum power_supply_property psp,
 883                                         union power_supply_propval *val)
 884 {
 885         int ret = 0;
 886         struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
 887
 888         mutex_lock(&di->lock);
 889         if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
 890                 cancel_delayed_work_sync(&di->work);
 891                 bq27xxx_battery_poll(&di->work.work);
 892         }
 893         mutex_unlock(&di->lock);
 894
 895         if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
 896                 return -ENODEV;
 897
 898         switch (psp) {
 899         case POWER_SUPPLY_PROP_STATUS:
 900                 ret = bq27xxx_battery_status(di, val);
 901                 break;
 902         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 903                 ret = bq27xxx_battery_voltage(di, val);
 904                 break;
 905         case POWER_SUPPLY_PROP_PRESENT:
 906                 val->intval = di->cache.flags < 0 ? 0 : 1;
 907                 break;
 908         case POWER_SUPPLY_PROP_CURRENT_NOW:
 909                 ret = bq27xxx_battery_current(di, val);
 910                 break;
 911         case POWER_SUPPLY_PROP_CAPACITY:
 912                 ret = bq27xxx_simple_value(di->cache.capacity, val);
 913                 break;
 914         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 915                 ret = bq27xxx_battery_capacity_level(di, val);
 916                 break;
 917         case POWER_SUPPLY_PROP_TEMP:
 918                 ret = bq27xxx_simple_value(di->cache.temperature, val);
 919                 if (ret == 0)
 920                         val->intval -= 2731; /* convert decidegree k to c */
 921                 break;
 922         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
 923                 ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
 924                 break;
 925         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 926                 ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
 927                 break;
 928         case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
 929                 ret = bq27xxx_simple_value(di->cache.time_to_full, val);
 930                 break;
 931         case POWER_SUPPLY_PROP_TECHNOLOGY:
 932                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 933                 break;
 934         case POWER_SUPPLY_PROP_CHARGE_NOW:
 935                 ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
 936                 break;
 937         case POWER_SUPPLY_PROP_CHARGE_FULL:
 938                 ret = bq27xxx_simple_value(di->cache.charge_full, val);
 939                 break;
 940         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 941                 ret = bq27xxx_simple_value(di->charge_design_full, val);
 942                 break;
 943         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 944                 ret = bq27xxx_simple_value(di->cache.cycle_count, val);
 945                 break;
 946         case POWER_SUPPLY_PROP_ENERGY_NOW:
 947                 ret = bq27xxx_simple_value(di->cache.energy, val);
 948                 break;
 949         case POWER_SUPPLY_PROP_POWER_AVG:
 950                 ret = bq27xxx_simple_value(di->cache.power_avg, val);
 951                 break;
 952         case POWER_SUPPLY_PROP_HEALTH:
 953                 ret = bq27xxx_simple_value(di->cache.health, val);
 954                 break;
 955         case POWER_SUPPLY_PROP_MANUFACTURER:
 956                 val->strval = BQ27XXX_MANUFACTURER;
 957                 break;
 958         default:
 959                 return -EINVAL;
 960         }
 961
 962         return ret;
 963 }
 964
 965 static void bq27xxx_external_power_changed(struct power_supply *psy)
 966 {
 967         struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
 968
 969         cancel_delayed_work_sync(&di->work);
 970         schedule_delayed_work(&di->work, 0);
 971 }
 972
 973 int bq27xxx_battery_setup(struct bq27xxx_device_info *di)
 974 {
 975         struct power_supply_desc *psy_desc;
 976         struct power_supply_config psy_cfg = { .drv_data = di, };
 977
 978         INIT_DELAYED_WORK(&di->work, bq27xxx_battery_poll);
 979         mutex_init(&di->lock);
 980         di->regs = bq27xxx_regs[di->chip];
 981
 982         psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
 983         if (!psy_desc)
 984                 return -ENOMEM;
 985
 986         psy_desc->name = di->name;
 987         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 988         psy_desc->properties = bq27xxx_battery_props[di->chip].props;
 989         psy_desc->num_properties = bq27xxx_battery_props[di->chip].size;
 990         psy_desc->get_property = bq27xxx_battery_get_property;
 991         psy_desc->external_power_changed = bq27xxx_external_power_changed;
 992
 993         di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
 994         if (IS_ERR(di->bat)) {
 995                 dev_err(di->dev, "failed to register battery\n");
 996                 return PTR_ERR(di->bat);
 997         }
 998
 999         dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
1000
1001         bq27xxx_battery_update(di);
1002
1003         mutex_lock(&bq27xxx_list_lock);
1004         list_add(&di->list, &bq27xxx_battery_devices);
1005         mutex_unlock(&bq27xxx_list_lock);
1006
1007         return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(bq27xxx_battery_setup);
1010
1011 void bq27xxx_battery_teardown(struct bq27xxx_device_info *di)
1012 {
1013         /*
1014          * power_supply_unregister call bq27xxx_battery_get_property which
1015          * call bq27xxx_battery_poll.
1016          * Make sure that bq27xxx_battery_poll will not call
1017          * schedule_delayed_work again after unregister (which cause OOPS).
1018          */
1019         poll_interval = 0;
1020
1021         cancel_delayed_work_sync(&di->work);
1022
1023         power_supply_unregister(di->bat);
1024
1025         mutex_lock(&bq27xxx_list_lock);
1026         list_del(&di->list);
1027         mutex_unlock(&bq27xxx_list_lock);
1028
1029         mutex_destroy(&di->lock);
1030 }
1031 EXPORT_SYMBOL_GPL(bq27xxx_battery_teardown);
1032
1033 static int bq27xxx_battery_platform_read(struct bq27xxx_device_info *di, u8 reg,
1034                                          bool single)
1035 {
1036         struct device *dev = di->dev;
1037         struct bq27xxx_platform_data *pdata = dev->platform_data;
1038         unsigned int timeout = 3;
1039         int upper, lower;
1040         int temp;
1041
1042         if (!single) {
1043                 /* Make sure the value has not changed in between reading the
1044                  * lower and the upper part */
1045                 upper = pdata->read(dev, reg + 1);
1046                 do {
1047                         temp = upper;
1048                         if (upper < 0)
1049                                 return upper;
1050
1051                         lower = pdata->read(dev, reg);
1052                         if (lower < 0)
1053                                 return lower;
1054
1055                         upper = pdata->read(dev, reg + 1);
1056                 } while (temp != upper && --timeout);
1057
1058                 if (timeout == 0)
1059                         return -EIO;
1060
1061                 return (upper << 8) | lower;
1062         }
1063
1064         return pdata->read(dev, reg);
1065 }
1066
1067 static int bq27xxx_battery_platform_probe(struct platform_device *pdev)
1068 {
1069         struct bq27xxx_device_info *di;
1070         struct bq27xxx_platform_data *pdata = pdev->dev.platform_data;
1071
1072         if (!pdata) {
1073                 dev_err(&pdev->dev, "no platform_data supplied\n");
1074                 return -EINVAL;
1075         }
1076
1077         if (!pdata->read) {
1078                 dev_err(&pdev->dev, "no hdq read callback supplied\n");
1079                 return -EINVAL;
1080         }
1081
1082         if (!pdata->chip) {
1083                 dev_err(&pdev->dev, "no device supplied\n");
1084                 return -EINVAL;
1085         }
1086
1087         di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1088         if (!di)
1089                 return -ENOMEM;
1090
1091         platform_set_drvdata(pdev, di);
1092
1093         di->dev = &pdev->dev;
1094         di->chip = pdata->chip;
1095         di->name = pdata->name ?: dev_name(&pdev->dev);
1096         di->bus.read = bq27xxx_battery_platform_read;
1097
1098         return bq27xxx_battery_setup(di);
1099 }
1100
1101 static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
1102 {
1103         struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
1104
1105         bq27xxx_battery_teardown(di);
1106
1107         return 0;
1108 }
1109
1110 static const struct platform_device_id bq27xxx_battery_platform_id_table[] = {
1111         { "bq27000-battery", },
1112         { /* sentinel */ }
1113 };
1114 MODULE_DEVICE_TABLE(platform, bq27xxx_battery_platform_id_table);
1115
1116 #ifdef CONFIG_OF
1117 static const struct of_device_id bq27xxx_battery_platform_of_match_table[] = {
1118         { .compatible = "ti,bq27000" },
1119         {},
1120 };
1121 MODULE_DEVICE_TABLE(of, bq27xxx_battery_platform_of_match_table);
1122 #endif
1123
1124 static struct platform_driver bq27xxx_battery_platform_driver = {
1125         .probe  = bq27xxx_battery_platform_probe,
1126         .remove = bq27xxx_battery_platform_remove,
1127         .driver = {
1128                 .name = "bq27000-battery",
1129                 .of_match_table = of_match_ptr(bq27xxx_battery_platform_of_match_table),
1130         },
1131         .id_table = bq27xxx_battery_platform_id_table,
1132 };
1133 module_platform_driver(bq27xxx_battery_platform_driver);
1134
1135 MODULE_ALIAS("platform:bq27000-battery");
1136
1137 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1138 MODULE_DESCRIPTION("BQ27xxx battery monitor driver");
1139 MODULE_LICENSE("GPL");