drivers/power/ds2760_battery.c

   1 /*
   2  * Driver for batteries with DS2760 chips inside.
   3  *
   4  * Copyright © 2007 Anton Vorontsov
   5  *             2004-2007 Matt Reimer
   6  *             2004 Szabolcs Gyurko
   7  *
   8  * Use consistent with the GNU GPL is permitted,
   9  * provided that this copyright notice is
  10  * preserved in its entirety in all copies and derived works.
  11  *
  12  * Author:  Anton Vorontsov <cbou@mail.ru>
  13  *          February 2007
  14  *
  15  *          Matt Reimer <mreimer@vpop.net>
  16  *          April 2004, 2005, 2007
  17  *
  18  *          Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
  19  *          September 2004
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/param.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/pm.h>
  27 #include <linux/slab.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/power_supply.h>
  30
  31 #include "../w1/w1.h"
  32 #include "../w1/slaves/w1_ds2760.h"
  33
  34 struct ds2760_device_info {
  35         struct device *dev;
  36
  37         /* DS2760 data, valid after calling ds2760_battery_read_status() */
  38         unsigned long update_time;      /* jiffies when data read */
  39         char raw[DS2760_DATA_SIZE];     /* raw DS2760 data */
  40         int voltage_raw;                /* units of 4.88 mV */
  41         int voltage_uV;                 /* units of µV */
  42         int current_raw;                /* units of 0.625 mA */
  43         int current_uA;                 /* units of µA */
  44         int accum_current_raw;          /* units of 0.25 mAh */
  45         int accum_current_uAh;          /* units of µAh */
  46         int temp_raw;                   /* units of 0.125 °C */
  47         int temp_C;                     /* units of 0.1 °C */
  48         int rated_capacity;             /* units of µAh */
  49         int rem_capacity;               /* percentage */
  50         int full_active_uAh;            /* units of µAh */
  51         int empty_uAh;                  /* units of µAh */
  52         int life_sec;                   /* units of seconds */
  53         int charge_status;              /* POWER_SUPPLY_STATUS_* */
  54
  55         int full_counter;
  56         struct power_supply *bat;
  57         struct power_supply_desc bat_desc;
  58         struct device *w1_dev;
  59         struct workqueue_struct *monitor_wqueue;
  60         struct delayed_work monitor_work;
  61         struct delayed_work set_charged_work;
  62 };
  63
  64 static unsigned int cache_time = 1000;
  65 module_param(cache_time, uint, 0644);
  66 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  67
  68 static bool pmod_enabled;
  69 module_param(pmod_enabled, bool, 0644);
  70 MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
  71
  72 static unsigned int rated_capacity;
  73 module_param(rated_capacity, uint, 0644);
  74 MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
  75
  76 static unsigned int current_accum;
  77 module_param(current_accum, uint, 0644);
  78 MODULE_PARM_DESC(current_accum, "current accumulator value");
  79
  80 /* Some batteries have their rated capacity stored a N * 10 mAh, while
  81  * others use an index into this table. */
  82 static int rated_capacities[] = {
  83         0,
  84         920,    /* Samsung */
  85         920,    /* BYD */
  86         920,    /* Lishen */
  87         920,    /* NEC */
  88         1440,   /* Samsung */
  89         1440,   /* BYD */
  90 #ifdef CONFIG_MACH_H4700
  91         1800,   /* HP iPAQ hx4700 3.7V 1800mAh (359113-001) */
  92 #else
  93         1440,   /* Lishen */
  94 #endif
  95         1440,   /* NEC */
  96         2880,   /* Samsung */
  97         2880,   /* BYD */
  98         2880,   /* Lishen */
  99         2880,   /* NEC */
 100 #ifdef CONFIG_MACH_H4700
 101         0,
 102         3600,   /* HP iPAQ hx4700 3.7V 3600mAh (359114-001) */
 103 #endif
 104 };
 105
 106 /* array is level at temps 0°C, 10°C, 20°C, 30°C, 40°C
 107  * temp is in Celsius */
 108 static int battery_interpolate(int array[], int temp)
 109 {
 110         int index, dt;
 111
 112         if (temp <= 0)
 113                 return array[0];
 114         if (temp >= 40)
 115                 return array[4];
 116
 117         index = temp / 10;
 118         dt    = temp % 10;
 119
 120         return array[index] + (((array[index + 1] - array[index]) * dt) / 10);
 121 }
 122
 123 static int ds2760_battery_read_status(struct ds2760_device_info *di)
 124 {
 125         int ret, i, start, count, scale[5];
 126
 127         if (di->update_time && time_before(jiffies, di->update_time +
 128                                            msecs_to_jiffies(cache_time)))
 129                 return 0;
 130
 131         /* The first time we read the entire contents of SRAM/EEPROM,
 132          * but after that we just read the interesting bits that change. */
 133         if (di->update_time == 0) {
 134                 start = 0;
 135                 count = DS2760_DATA_SIZE;
 136         } else {
 137                 start = DS2760_VOLTAGE_MSB;
 138                 count = DS2760_TEMP_LSB - start + 1;
 139         }
 140
 141         ret = w1_ds2760_read(di->w1_dev, di->raw + start, start, count);
 142         if (ret != count) {
 143                 dev_warn(di->dev, "call to w1_ds2760_read failed (0x%p)\n",
 144                          di->w1_dev);
 145                 return 1;
 146         }
 147
 148         di->update_time = jiffies;
 149
 150         /* DS2760 reports voltage in units of 4.88mV, but the battery class
 151          * reports in units of uV, so convert by multiplying by 4880. */
 152         di->voltage_raw = (di->raw[DS2760_VOLTAGE_MSB] << 3) |
 153                           (di->raw[DS2760_VOLTAGE_LSB] >> 5);
 154         di->voltage_uV = di->voltage_raw * 4880;
 155
 156         /* DS2760 reports current in signed units of 0.625mA, but the battery
 157          * class reports in units of µA, so convert by multiplying by 625. */
 158         di->current_raw =
 159             (((signed char)di->raw[DS2760_CURRENT_MSB]) << 5) |
 160                           (di->raw[DS2760_CURRENT_LSB] >> 3);
 161         di->current_uA = di->current_raw * 625;
 162
 163         /* DS2760 reports accumulated current in signed units of 0.25mAh. */
 164         di->accum_current_raw =
 165             (((signed char)di->raw[DS2760_CURRENT_ACCUM_MSB]) << 8) |
 166                            di->raw[DS2760_CURRENT_ACCUM_LSB];
 167         di->accum_current_uAh = di->accum_current_raw * 250;
 168
 169         /* DS2760 reports temperature in signed units of 0.125°C, but the
 170          * battery class reports in units of 1/10 °C, so we convert by
 171          * multiplying by .125 * 10 = 1.25. */
 172         di->temp_raw = (((signed char)di->raw[DS2760_TEMP_MSB]) << 3) |
 173                                      (di->raw[DS2760_TEMP_LSB] >> 5);
 174         di->temp_C = di->temp_raw + (di->temp_raw / 4);
 175
 176         /* At least some battery monitors (e.g. HP iPAQ) store the battery's
 177          * maximum rated capacity. */
 178         if (di->raw[DS2760_RATED_CAPACITY] < ARRAY_SIZE(rated_capacities))
 179                 di->rated_capacity = rated_capacities[
 180                         (unsigned int)di->raw[DS2760_RATED_CAPACITY]];
 181         else
 182                 di->rated_capacity = di->raw[DS2760_RATED_CAPACITY] * 10;
 183
 184         di->rated_capacity *= 1000; /* convert to µAh */
 185
 186         /* Calculate the full level at the present temperature. */
 187         di->full_active_uAh = di->raw[DS2760_ACTIVE_FULL] << 8 |
 188                               di->raw[DS2760_ACTIVE_FULL + 1];
 189
 190         /* If the full_active_uAh value is not given, fall back to the rated
 191          * capacity. This is likely to happen when chips are not part of the
 192          * battery pack and is therefore not bootstrapped. */
 193         if (di->full_active_uAh == 0)
 194                 di->full_active_uAh = di->rated_capacity / 1000L;
 195
 196         scale[0] = di->full_active_uAh;
 197         for (i = 1; i < 5; i++)
 198                 scale[i] = scale[i - 1] + di->raw[DS2760_ACTIVE_FULL + 1 + i];
 199
 200         di->full_active_uAh = battery_interpolate(scale, di->temp_C / 10);
 201         di->full_active_uAh *= 1000; /* convert to µAh */
 202
 203         /* Calculate the empty level at the present temperature. */
 204         scale[4] = di->raw[DS2760_ACTIVE_EMPTY + 4];
 205         for (i = 3; i >= 0; i--)
 206                 scale[i] = scale[i + 1] + di->raw[DS2760_ACTIVE_EMPTY + i];
 207
 208         di->empty_uAh = battery_interpolate(scale, di->temp_C / 10);
 209         di->empty_uAh *= 1000; /* convert to µAh */
 210
 211         if (di->full_active_uAh == di->empty_uAh)
 212                 di->rem_capacity = 0;
 213         else
 214                 /* From Maxim Application Note 131: remaining capacity =
 215                  * ((ICA - Empty Value) / (Full Value - Empty Value)) x 100% */
 216                 di->rem_capacity = ((di->accum_current_uAh - di->empty_uAh) * 100L) /
 217                                     (di->full_active_uAh - di->empty_uAh);
 218
 219         if (di->rem_capacity < 0)
 220                 di->rem_capacity = 0;
 221         if (di->rem_capacity > 100)
 222                 di->rem_capacity = 100;
 223
 224         if (di->current_uA < -100L)
 225                 di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
 226                                         / (di->current_uA / 100L);
 227         else
 228                 di->life_sec = 0;
 229
 230         return 0;
 231 }
 232
 233 static void ds2760_battery_set_current_accum(struct ds2760_device_info *di,
 234                                              unsigned int acr_val)
 235 {
 236         unsigned char acr[2];
 237
 238         /* acr is in units of 0.25 mAh */
 239         acr_val *= 4L;
 240         acr_val /= 1000;
 241
 242         acr[0] = acr_val >> 8;
 243         acr[1] = acr_val & 0xff;
 244
 245         if (w1_ds2760_write(di->w1_dev, acr, DS2760_CURRENT_ACCUM_MSB, 2) < 2)
 246                 dev_warn(di->dev, "ACR write failed\n");
 247 }
 248
 249 static void ds2760_battery_update_status(struct ds2760_device_info *di)
 250 {
 251         int old_charge_status = di->charge_status;
 252
 253         ds2760_battery_read_status(di);
 254
 255         if (di->charge_status == POWER_SUPPLY_STATUS_UNKNOWN)
 256                 di->full_counter = 0;
 257
 258         if (power_supply_am_i_supplied(di->bat)) {
 259                 if (di->current_uA > 10000) {
 260                         di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
 261                         di->full_counter = 0;
 262                 } else if (di->current_uA < -5000) {
 263                         if (di->charge_status != POWER_SUPPLY_STATUS_NOT_CHARGING)
 264                                 dev_notice(di->dev, "not enough power to "
 265                                            "charge\n");
 266                         di->charge_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 267                         di->full_counter = 0;
 268                 } else if (di->current_uA < 10000 &&
 269                             di->charge_status != POWER_SUPPLY_STATUS_FULL) {
 270
 271                         /* Don't consider the battery to be full unless
 272                          * we've seen the current < 10 mA at least two
 273                          * consecutive times. */
 274
 275                         di->full_counter++;
 276
 277                         if (di->full_counter < 2) {
 278                                 di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
 279                         } else {
 280                                 di->charge_status = POWER_SUPPLY_STATUS_FULL;
 281                                 ds2760_battery_set_current_accum(di,
 282                                                 di->full_active_uAh);
 283                         }
 284                 }
 285         } else {
 286                 di->charge_status = POWER_SUPPLY_STATUS_DISCHARGING;
 287                 di->full_counter = 0;
 288         }
 289
 290         if (di->charge_status != old_charge_status)
 291                 power_supply_changed(di->bat);
 292 }
 293
 294 static void ds2760_battery_write_status(struct ds2760_device_info *di,
 295                                         char status)
 296 {
 297         if (status == di->raw[DS2760_STATUS_REG])
 298                 return;
 299
 300         w1_ds2760_write(di->w1_dev, &status, DS2760_STATUS_WRITE_REG, 1);
 301         w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
 302         w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
 303 }
 304
 305 static void ds2760_battery_write_rated_capacity(struct ds2760_device_info *di,
 306                                                 unsigned char rated_capacity)
 307 {
 308         if (rated_capacity == di->raw[DS2760_RATED_CAPACITY])
 309                 return;
 310
 311         w1_ds2760_write(di->w1_dev, &rated_capacity, DS2760_RATED_CAPACITY, 1);
 312         w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
 313         w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
 314 }
 315
 316 static void ds2760_battery_write_active_full(struct ds2760_device_info *di,
 317                                              int active_full)
 318 {
 319         unsigned char tmp[2] = {
 320                 active_full >> 8,
 321                 active_full & 0xff
 322         };
 323
 324         if (tmp[0] == di->raw[DS2760_ACTIVE_FULL] &&
 325             tmp[1] == di->raw[DS2760_ACTIVE_FULL + 1])
 326                 return;
 327
 328         w1_ds2760_write(di->w1_dev, tmp, DS2760_ACTIVE_FULL, sizeof(tmp));
 329         w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK0);
 330         w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK0);
 331
 332         /* Write to the di->raw[] buffer directly - the DS2760_ACTIVE_FULL
 333          * values won't be read back by ds2760_battery_read_status() */
 334         di->raw[DS2760_ACTIVE_FULL] = tmp[0];
 335         di->raw[DS2760_ACTIVE_FULL + 1] = tmp[1];
 336 }
 337
 338 static void ds2760_battery_work(struct work_struct *work)
 339 {
 340         struct ds2760_device_info *di = container_of(work,
 341                 struct ds2760_device_info, monitor_work.work);
 342         const int interval = HZ * 60;
 343
 344         dev_dbg(di->dev, "%s\n", __func__);
 345
 346         ds2760_battery_update_status(di);
 347         queue_delayed_work(di->monitor_wqueue, &di->monitor_work, interval);
 348 }
 349
 350 static void ds2760_battery_external_power_changed(struct power_supply *psy)
 351 {
 352         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 353
 354         dev_dbg(di->dev, "%s\n", __func__);
 355
 356         mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ/10);
 357 }
 358
 359
 360 static void ds2760_battery_set_charged_work(struct work_struct *work)
 361 {
 362         char bias;
 363         struct ds2760_device_info *di = container_of(work,
 364                 struct ds2760_device_info, set_charged_work.work);
 365
 366         dev_dbg(di->dev, "%s\n", __func__);
 367
 368         ds2760_battery_read_status(di);
 369
 370         /* When we get notified by external circuitry that the battery is
 371          * considered fully charged now, we know that there is no current
 372          * flow any more. However, the ds2760's internal current meter is
 373          * too inaccurate to rely on - spec say something ~15% failure.
 374          * Hence, we use the current offset bias register to compensate
 375          * that error.
 376          */
 377
 378         if (!power_supply_am_i_supplied(di->bat))
 379                 return;
 380
 381         bias = (signed char) di->current_raw +
 382                 (signed char) di->raw[DS2760_CURRENT_OFFSET_BIAS];
 383
 384         dev_dbg(di->dev, "%s: bias = %d\n", __func__, bias);
 385
 386         w1_ds2760_write(di->w1_dev, &bias, DS2760_CURRENT_OFFSET_BIAS, 1);
 387         w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
 388         w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
 389
 390         /* Write to the di->raw[] buffer directly - the CURRENT_OFFSET_BIAS
 391          * value won't be read back by ds2760_battery_read_status() */
 392         di->raw[DS2760_CURRENT_OFFSET_BIAS] = bias;
 393 }
 394
 395 static void ds2760_battery_set_charged(struct power_supply *psy)
 396 {
 397         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 398
 399         /* postpone the actual work by 20 secs. This is for debouncing GPIO
 400          * signals and to let the current value settle. See AN4188. */
 401         mod_delayed_work(di->monitor_wqueue, &di->set_charged_work, HZ * 20);
 402 }
 403
 404 static int ds2760_battery_get_property(struct power_supply *psy,
 405                                        enum power_supply_property psp,
 406                                        union power_supply_propval *val)
 407 {
 408         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 409
 410         switch (psp) {
 411         case POWER_SUPPLY_PROP_STATUS:
 412                 val->intval = di->charge_status;
 413                 return 0;
 414         default:
 415                 break;
 416         }
 417
 418         ds2760_battery_read_status(di);
 419
 420         switch (psp) {
 421         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 422                 val->intval = di->voltage_uV;
 423                 break;
 424         case POWER_SUPPLY_PROP_CURRENT_NOW:
 425                 val->intval = di->current_uA;
 426                 break;
 427         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 428                 val->intval = di->rated_capacity;
 429                 break;
 430         case POWER_SUPPLY_PROP_CHARGE_FULL:
 431                 val->intval = di->full_active_uAh;
 432                 break;
 433         case POWER_SUPPLY_PROP_CHARGE_EMPTY:
 434                 val->intval = di->empty_uAh;
 435                 break;
 436         case POWER_SUPPLY_PROP_CHARGE_NOW:
 437                 val->intval = di->accum_current_uAh;
 438                 break;
 439         case POWER_SUPPLY_PROP_TEMP:
 440                 val->intval = di->temp_C;
 441                 break;
 442         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
 443                 val->intval = di->life_sec;
 444                 break;
 445         case POWER_SUPPLY_PROP_CAPACITY:
 446                 val->intval = di->rem_capacity;
 447                 break;
 448         default:
 449                 return -EINVAL;
 450         }
 451
 452         return 0;
 453 }
 454
 455 static int ds2760_battery_set_property(struct power_supply *psy,
 456                                        enum power_supply_property psp,
 457                                        const union power_supply_propval *val)
 458 {
 459         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 460
 461         switch (psp) {
 462         case POWER_SUPPLY_PROP_CHARGE_FULL:
 463                 /* the interface counts in uAh, convert the value */
 464                 ds2760_battery_write_active_full(di, val->intval / 1000L);
 465                 break;
 466
 467         case POWER_SUPPLY_PROP_CHARGE_NOW:
 468                 /* ds2760_battery_set_current_accum() does the conversion */
 469                 ds2760_battery_set_current_accum(di, val->intval);
 470                 break;
 471
 472         default:
 473                 return -EPERM;
 474         }
 475
 476         return 0;
 477 }
 478
 479 static int ds2760_battery_property_is_writeable(struct power_supply *psy,
 480                                                 enum power_supply_property psp)
 481 {
 482         switch (psp) {
 483         case POWER_SUPPLY_PROP_CHARGE_FULL:
 484         case POWER_SUPPLY_PROP_CHARGE_NOW:
 485                 return 1;
 486
 487         default:
 488                 break;
 489         }
 490
 491         return 0;
 492 }
 493
 494 static enum power_supply_property ds2760_battery_props[] = {
 495         POWER_SUPPLY_PROP_STATUS,
 496         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 497         POWER_SUPPLY_PROP_CURRENT_NOW,
 498         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 499         POWER_SUPPLY_PROP_CHARGE_FULL,
 500         POWER_SUPPLY_PROP_CHARGE_EMPTY,
 501         POWER_SUPPLY_PROP_CHARGE_NOW,
 502         POWER_SUPPLY_PROP_TEMP,
 503         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 504         POWER_SUPPLY_PROP_CAPACITY,
 505 };
 506
 507 static int ds2760_battery_probe(struct platform_device *pdev)
 508 {
 509         struct power_supply_config psy_cfg = {};
 510         char status;
 511         int retval = 0;
 512         struct ds2760_device_info *di;
 513
 514         di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
 515         if (!di) {
 516                 retval = -ENOMEM;
 517                 goto di_alloc_failed;
 518         }
 519
 520         platform_set_drvdata(pdev, di);
 521
 522         di->dev                         = &pdev->dev;
 523         di->w1_dev                      = pdev->dev.parent;
 524         di->bat_desc.name               = dev_name(&pdev->dev);
 525         di->bat_desc.type               = POWER_SUPPLY_TYPE_BATTERY;
 526         di->bat_desc.properties         = ds2760_battery_props;
 527         di->bat_desc.num_properties     = ARRAY_SIZE(ds2760_battery_props);
 528         di->bat_desc.get_property       = ds2760_battery_get_property;
 529         di->bat_desc.set_property       = ds2760_battery_set_property;
 530         di->bat_desc.property_is_writeable =
 531                                   ds2760_battery_property_is_writeable;
 532         di->bat_desc.set_charged        = ds2760_battery_set_charged;
 533         di->bat_desc.external_power_changed =
 534                                   ds2760_battery_external_power_changed;
 535
 536         psy_cfg.drv_data                = di;
 537
 538         di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
 539
 540         /* enable sleep mode feature */
 541         ds2760_battery_read_status(di);
 542         status = di->raw[DS2760_STATUS_REG];
 543         if (pmod_enabled)
 544                 status |= DS2760_STATUS_PMOD;
 545         else
 546                 status &= ~DS2760_STATUS_PMOD;
 547
 548         ds2760_battery_write_status(di, status);
 549
 550         /* set rated capacity from module param */
 551         if (rated_capacity)
 552                 ds2760_battery_write_rated_capacity(di, rated_capacity);
 553
 554         /* set current accumulator if given as parameter.
 555          * this should only be done for bootstrapping the value */
 556         if (current_accum)
 557                 ds2760_battery_set_current_accum(di, current_accum);
 558
 559         di->bat = power_supply_register(&pdev->dev, &di->bat_desc, &psy_cfg);
 560         if (IS_ERR(di->bat)) {
 561                 dev_err(di->dev, "failed to register battery\n");
 562                 retval = PTR_ERR(di->bat);
 563                 goto batt_failed;
 564         }
 565
 566         INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work);
 567         INIT_DELAYED_WORK(&di->set_charged_work,
 568                           ds2760_battery_set_charged_work);
 569         di->monitor_wqueue = create_singlethread_workqueue(dev_name(&pdev->dev));
 570         if (!di->monitor_wqueue) {
 571                 retval = -ESRCH;
 572                 goto workqueue_failed;
 573         }
 574         queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ * 1);
 575
 576         goto success;
 577
 578 workqueue_failed:
 579         power_supply_unregister(di->bat);
 580 batt_failed:
 581 di_alloc_failed:
 582 success:
 583         return retval;
 584 }
 585
 586 static int ds2760_battery_remove(struct platform_device *pdev)
 587 {
 588         struct ds2760_device_info *di = platform_get_drvdata(pdev);
 589
 590         cancel_delayed_work_sync(&di->monitor_work);
 591         cancel_delayed_work_sync(&di->set_charged_work);
 592         destroy_workqueue(di->monitor_wqueue);
 593         power_supply_unregister(di->bat);
 594
 595         return 0;
 596 }
 597
 598 #ifdef CONFIG_PM
 599
 600 static int ds2760_battery_suspend(struct platform_device *pdev,
 601                                   pm_message_t state)
 602 {
 603         struct ds2760_device_info *di = platform_get_drvdata(pdev);
 604
 605         di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
 606
 607         return 0;
 608 }
 609
 610 static int ds2760_battery_resume(struct platform_device *pdev)
 611 {
 612         struct ds2760_device_info *di = platform_get_drvdata(pdev);
 613
 614         di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
 615         power_supply_changed(di->bat);
 616
 617         mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ);
 618
 619         return 0;
 620 }
 621
 622 #else
 623
 624 #define ds2760_battery_suspend NULL
 625 #define ds2760_battery_resume NULL
 626
 627 #endif /* CONFIG_PM */
 628
 629 MODULE_ALIAS("platform:ds2760-battery");
 630
 631 static struct platform_driver ds2760_battery_driver = {
 632         .driver = {
 633                 .name = "ds2760-battery",
 634         },
 635         .probe    = ds2760_battery_probe,
 636         .remove   = ds2760_battery_remove,
 637         .suspend  = ds2760_battery_suspend,
 638         .resume   = ds2760_battery_resume,
 639 };
 640
 641 module_platform_driver(ds2760_battery_driver);
 642
 643 MODULE_LICENSE("GPL");
 644 MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
 645               "Matt Reimer <mreimer@vpop.net>, "
 646               "Anton Vorontsov <cbou@mail.ru>");
 647 MODULE_DESCRIPTION("ds2760 battery driver");