ds2760_battery.c revision 9c6f8740d0c8d2b4de78511257f38384f4cbb292
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 34struct 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 device *w1_dev; 58 struct workqueue_struct *monitor_wqueue; 59 struct delayed_work monitor_work; 60 struct delayed_work set_charged_work; 61}; 62 63static unsigned int cache_time = 1000; 64module_param(cache_time, uint, 0644); 65MODULE_PARM_DESC(cache_time, "cache time in milliseconds"); 66 67static unsigned int pmod_enabled; 68module_param(pmod_enabled, bool, 0644); 69MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit"); 70 71static unsigned int rated_capacity; 72module_param(rated_capacity, uint, 0644); 73MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index"); 74 75static unsigned int current_accum; 76module_param(current_accum, uint, 0644); 77MODULE_PARM_DESC(current_accum, "current accumulator value"); 78 79/* Some batteries have their rated capacity stored a N * 10 mAh, while 80 * others use an index into this table. */ 81static int rated_capacities[] = { 82 0, 83 920, /* Samsung */ 84 920, /* BYD */ 85 920, /* Lishen */ 86 920, /* NEC */ 87 1440, /* Samsung */ 88 1440, /* BYD */ 89#ifdef CONFIG_MACH_H4700 90 1800, /* HP iPAQ hx4700 3.7V 1800mAh (359113-001) */ 91#else 92 1440, /* Lishen */ 93#endif 94 1440, /* NEC */ 95 2880, /* Samsung */ 96 2880, /* BYD */ 97 2880, /* Lishen */ 98 2880 /* NEC */ 99}; 100 101/* array is level at temps 0°C, 10°C, 20°C, 30°C, 40°C 102 * temp is in Celsius */ 103static int battery_interpolate(int array[], int temp) 104{ 105 int index, dt; 106 107 if (temp <= 0) 108 return array[0]; 109 if (temp >= 40) 110 return array[4]; 111 112 index = temp / 10; 113 dt = temp % 10; 114 115 return array[index] + (((array[index + 1] - array[index]) * dt) / 10); 116} 117 118static int ds2760_battery_read_status(struct ds2760_device_info *di) 119{ 120 int ret, i, start, count, scale[5]; 121 122 if (di->update_time && time_before(jiffies, di->update_time + 123 msecs_to_jiffies(cache_time))) 124 return 0; 125 126 /* The first time we read the entire contents of SRAM/EEPROM, 127 * but after that we just read the interesting bits that change. */ 128 if (di->update_time == 0) { 129 start = 0; 130 count = DS2760_DATA_SIZE; 131 } else { 132 start = DS2760_VOLTAGE_MSB; 133 count = DS2760_TEMP_LSB - start + 1; 134 } 135 136 ret = w1_ds2760_read(di->w1_dev, di->raw + start, start, count); 137 if (ret != count) { 138 dev_warn(di->dev, "call to w1_ds2760_read failed (0x%p)\n", 139 di->w1_dev); 140 return 1; 141 } 142 143 di->update_time = jiffies; 144 145 /* DS2760 reports voltage in units of 4.88mV, but the battery class 146 * reports in units of uV, so convert by multiplying by 4880. */ 147 di->voltage_raw = (di->raw[DS2760_VOLTAGE_MSB] << 3) | 148 (di->raw[DS2760_VOLTAGE_LSB] >> 5); 149 di->voltage_uV = di->voltage_raw * 4880; 150 151 /* DS2760 reports current in signed units of 0.625mA, but the battery 152 * class reports in units of µA, so convert by multiplying by 625. */ 153 di->current_raw = 154 (((signed char)di->raw[DS2760_CURRENT_MSB]) << 5) | 155 (di->raw[DS2760_CURRENT_LSB] >> 3); 156 di->current_uA = di->current_raw * 625; 157 158 /* DS2760 reports accumulated current in signed units of 0.25mAh. */ 159 di->accum_current_raw = 160 (((signed char)di->raw[DS2760_CURRENT_ACCUM_MSB]) << 8) | 161 di->raw[DS2760_CURRENT_ACCUM_LSB]; 162 di->accum_current_uAh = di->accum_current_raw * 250; 163 164 /* DS2760 reports temperature in signed units of 0.125°C, but the 165 * battery class reports in units of 1/10 °C, so we convert by 166 * multiplying by .125 * 10 = 1.25. */ 167 di->temp_raw = (((signed char)di->raw[DS2760_TEMP_MSB]) << 3) | 168 (di->raw[DS2760_TEMP_LSB] >> 5); 169 di->temp_C = di->temp_raw + (di->temp_raw / 4); 170 171 /* At least some battery monitors (e.g. HP iPAQ) store the battery's 172 * maximum rated capacity. */ 173 if (di->raw[DS2760_RATED_CAPACITY] < ARRAY_SIZE(rated_capacities)) 174 di->rated_capacity = rated_capacities[ 175 (unsigned int)di->raw[DS2760_RATED_CAPACITY]]; 176 else 177 di->rated_capacity = di->raw[DS2760_RATED_CAPACITY] * 10; 178 179 di->rated_capacity *= 1000; /* convert to µAh */ 180 181 /* Calculate the full level at the present temperature. */ 182 di->full_active_uAh = di->raw[DS2760_ACTIVE_FULL] << 8 | 183 di->raw[DS2760_ACTIVE_FULL + 1]; 184 185 /* If the full_active_uAh value is not given, fall back to the rated 186 * capacity. This is likely to happen when chips are not part of the 187 * battery pack and is therefore not bootstrapped. */ 188 if (di->full_active_uAh == 0) 189 di->full_active_uAh = di->rated_capacity / 1000L; 190 191 scale[0] = di->full_active_uAh; 192 for (i = 1; i < 5; i++) 193 scale[i] = scale[i - 1] + di->raw[DS2760_ACTIVE_FULL + 1 + i]; 194 195 di->full_active_uAh = battery_interpolate(scale, di->temp_C / 10); 196 di->full_active_uAh *= 1000; /* convert to µAh */ 197 198 /* Calculate the empty level at the present temperature. */ 199 scale[4] = di->raw[DS2760_ACTIVE_EMPTY + 4]; 200 for (i = 3; i >= 0; i--) 201 scale[i] = scale[i + 1] + di->raw[DS2760_ACTIVE_EMPTY + i]; 202 203 di->empty_uAh = battery_interpolate(scale, di->temp_C / 10); 204 di->empty_uAh *= 1000; /* convert to µAh */ 205 206 if (di->full_active_uAh == di->empty_uAh) 207 di->rem_capacity = 0; 208 else 209 /* From Maxim Application Note 131: remaining capacity = 210 * ((ICA - Empty Value) / (Full Value - Empty Value)) x 100% */ 211 di->rem_capacity = ((di->accum_current_uAh - di->empty_uAh) * 100L) / 212 (di->full_active_uAh - di->empty_uAh); 213 214 if (di->rem_capacity < 0) 215 di->rem_capacity = 0; 216 if (di->rem_capacity > 100) 217 di->rem_capacity = 100; 218 219 if (di->current_uA < -100L) 220 di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L) 221 / (di->current_uA / 100L); 222 else 223 di->life_sec = 0; 224 225 return 0; 226} 227 228static void ds2760_battery_set_current_accum(struct ds2760_device_info *di, 229 unsigned int acr_val) 230{ 231 unsigned char acr[2]; 232 233 /* acr is in units of 0.25 mAh */ 234 acr_val *= 4L; 235 acr_val /= 1000; 236 237 acr[0] = acr_val >> 8; 238 acr[1] = acr_val & 0xff; 239 240 if (w1_ds2760_write(di->w1_dev, acr, DS2760_CURRENT_ACCUM_MSB, 2) < 2) 241 dev_warn(di->dev, "ACR write failed\n"); 242} 243 244static void ds2760_battery_update_status(struct ds2760_device_info *di) 245{ 246 int old_charge_status = di->charge_status; 247 248 ds2760_battery_read_status(di); 249 250 if (di->charge_status == POWER_SUPPLY_STATUS_UNKNOWN) 251 di->full_counter = 0; 252 253 if (power_supply_am_i_supplied(&di->bat)) { 254 if (di->current_uA > 10000) { 255 di->charge_status = POWER_SUPPLY_STATUS_CHARGING; 256 di->full_counter = 0; 257 } else if (di->current_uA < -5000) { 258 if (di->charge_status != POWER_SUPPLY_STATUS_NOT_CHARGING) 259 dev_notice(di->dev, "not enough power to " 260 "charge\n"); 261 di->charge_status = POWER_SUPPLY_STATUS_NOT_CHARGING; 262 di->full_counter = 0; 263 } else if (di->current_uA < 10000 && 264 di->charge_status != POWER_SUPPLY_STATUS_FULL) { 265 266 /* Don't consider the battery to be full unless 267 * we've seen the current < 10 mA at least two 268 * consecutive times. */ 269 270 di->full_counter++; 271 272 if (di->full_counter < 2) { 273 di->charge_status = POWER_SUPPLY_STATUS_CHARGING; 274 } else { 275 di->charge_status = POWER_SUPPLY_STATUS_FULL; 276 ds2760_battery_set_current_accum(di, 277 di->full_active_uAh); 278 } 279 } 280 } else { 281 di->charge_status = POWER_SUPPLY_STATUS_DISCHARGING; 282 di->full_counter = 0; 283 } 284 285 if (di->charge_status != old_charge_status) 286 power_supply_changed(&di->bat); 287} 288 289static void ds2760_battery_write_status(struct ds2760_device_info *di, 290 char status) 291{ 292 if (status == di->raw[DS2760_STATUS_REG]) 293 return; 294 295 w1_ds2760_write(di->w1_dev, &status, DS2760_STATUS_WRITE_REG, 1); 296 w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1); 297 w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1); 298} 299 300static void ds2760_battery_write_rated_capacity(struct ds2760_device_info *di, 301 unsigned char rated_capacity) 302{ 303 if (rated_capacity == di->raw[DS2760_RATED_CAPACITY]) 304 return; 305 306 w1_ds2760_write(di->w1_dev, &rated_capacity, DS2760_RATED_CAPACITY, 1); 307 w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1); 308 w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1); 309} 310 311static void ds2760_battery_write_active_full(struct ds2760_device_info *di, 312 int active_full) 313{ 314 unsigned char tmp[2] = { 315 active_full >> 8, 316 active_full & 0xff 317 }; 318 319 if (tmp[0] == di->raw[DS2760_ACTIVE_FULL] && 320 tmp[1] == di->raw[DS2760_ACTIVE_FULL + 1]) 321 return; 322 323 w1_ds2760_write(di->w1_dev, tmp, DS2760_ACTIVE_FULL, sizeof(tmp)); 324 w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK0); 325 w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK0); 326 327 /* Write to the di->raw[] buffer directly - the DS2760_ACTIVE_FULL 328 * values won't be read back by ds2760_battery_read_status() */ 329 di->raw[DS2760_ACTIVE_FULL] = tmp[0]; 330 di->raw[DS2760_ACTIVE_FULL + 1] = tmp[1]; 331} 332 333static void ds2760_battery_work(struct work_struct *work) 334{ 335 struct ds2760_device_info *di = container_of(work, 336 struct ds2760_device_info, monitor_work.work); 337 const int interval = HZ * 60; 338 339 dev_dbg(di->dev, "%s\n", __func__); 340 341 ds2760_battery_update_status(di); 342 queue_delayed_work(di->monitor_wqueue, &di->monitor_work, interval); 343} 344 345#define to_ds2760_device_info(x) container_of((x), struct ds2760_device_info, \ 346 bat); 347 348static void ds2760_battery_external_power_changed(struct power_supply *psy) 349{ 350 struct ds2760_device_info *di = to_ds2760_device_info(psy); 351 352 dev_dbg(di->dev, "%s\n", __func__); 353 354 cancel_delayed_work(&di->monitor_work); 355 queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ/10); 356} 357 358 359static void ds2760_battery_set_charged_work(struct work_struct *work) 360{ 361 char bias; 362 struct ds2760_device_info *di = container_of(work, 363 struct ds2760_device_info, set_charged_work.work); 364 365 dev_dbg(di->dev, "%s\n", __func__); 366 367 ds2760_battery_read_status(di); 368 369 /* When we get notified by external circuitry that the battery is 370 * considered fully charged now, we know that there is no current 371 * flow any more. However, the ds2760's internal current meter is 372 * too inaccurate to rely on - spec say something ~15% failure. 373 * Hence, we use the current offset bias register to compensate 374 * that error. 375 */ 376 377 if (!power_supply_am_i_supplied(&di->bat)) 378 return; 379 380 bias = (signed char) di->current_raw + 381 (signed char) di->raw[DS2760_CURRENT_OFFSET_BIAS]; 382 383 dev_dbg(di->dev, "%s: bias = %d\n", __func__, bias); 384 385 w1_ds2760_write(di->w1_dev, &bias, DS2760_CURRENT_OFFSET_BIAS, 1); 386 w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1); 387 w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1); 388 389 /* Write to the di->raw[] buffer directly - the CURRENT_OFFSET_BIAS 390 * value won't be read back by ds2760_battery_read_status() */ 391 di->raw[DS2760_CURRENT_OFFSET_BIAS] = bias; 392} 393 394static void ds2760_battery_set_charged(struct power_supply *psy) 395{ 396 struct ds2760_device_info *di = to_ds2760_device_info(psy); 397 398 /* postpone the actual work by 20 secs. This is for debouncing GPIO 399 * signals and to let the current value settle. See AN4188. */ 400 cancel_delayed_work(&di->set_charged_work); 401 queue_delayed_work(di->monitor_wqueue, &di->set_charged_work, HZ * 20); 402} 403 404static 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 = to_ds2760_device_info(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 455static 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 = to_ds2760_device_info(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 479static 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 494static 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 507static int ds2760_battery_probe(struct platform_device *pdev) 508{ 509 char status; 510 int retval = 0; 511 struct ds2760_device_info *di; 512 513 di = kzalloc(sizeof(*di), GFP_KERNEL); 514 if (!di) { 515 retval = -ENOMEM; 516 goto di_alloc_failed; 517 } 518 519 platform_set_drvdata(pdev, di); 520 521 di->dev = &pdev->dev; 522 di->w1_dev = pdev->dev.parent; 523 di->bat.name = dev_name(&pdev->dev); 524 di->bat.type = POWER_SUPPLY_TYPE_BATTERY; 525 di->bat.properties = ds2760_battery_props; 526 di->bat.num_properties = ARRAY_SIZE(ds2760_battery_props); 527 di->bat.get_property = ds2760_battery_get_property; 528 di->bat.set_property = ds2760_battery_set_property; 529 di->bat.property_is_writeable = 530 ds2760_battery_property_is_writeable; 531 di->bat.set_charged = ds2760_battery_set_charged; 532 di->bat.external_power_changed = 533 ds2760_battery_external_power_changed; 534 535 di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN; 536 537 /* enable sleep mode feature */ 538 ds2760_battery_read_status(di); 539 status = di->raw[DS2760_STATUS_REG]; 540 if (pmod_enabled) 541 status |= DS2760_STATUS_PMOD; 542 else 543 status &= ~DS2760_STATUS_PMOD; 544 545 ds2760_battery_write_status(di, status); 546 547 /* set rated capacity from module param */ 548 if (rated_capacity) 549 ds2760_battery_write_rated_capacity(di, rated_capacity); 550 551 /* set current accumulator if given as parameter. 552 * this should only be done for bootstrapping the value */ 553 if (current_accum) 554 ds2760_battery_set_current_accum(di, current_accum); 555 556 retval = power_supply_register(&pdev->dev, &di->bat); 557 if (retval) { 558 dev_err(di->dev, "failed to register battery\n"); 559 goto batt_failed; 560 } 561 562 INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work); 563 INIT_DELAYED_WORK(&di->set_charged_work, 564 ds2760_battery_set_charged_work); 565 di->monitor_wqueue = create_singlethread_workqueue(dev_name(&pdev->dev)); 566 if (!di->monitor_wqueue) { 567 retval = -ESRCH; 568 goto workqueue_failed; 569 } 570 queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ * 1); 571 572 goto success; 573 574workqueue_failed: 575 power_supply_unregister(&di->bat); 576batt_failed: 577 kfree(di); 578di_alloc_failed: 579success: 580 return retval; 581} 582 583static int ds2760_battery_remove(struct platform_device *pdev) 584{ 585 struct ds2760_device_info *di = platform_get_drvdata(pdev); 586 587 cancel_delayed_work_sync(&di->monitor_work); 588 cancel_delayed_work_sync(&di->set_charged_work); 589 destroy_workqueue(di->monitor_wqueue); 590 power_supply_unregister(&di->bat); 591 kfree(di); 592 593 return 0; 594} 595 596#ifdef CONFIG_PM 597 598static int ds2760_battery_suspend(struct platform_device *pdev, 599 pm_message_t state) 600{ 601 struct ds2760_device_info *di = platform_get_drvdata(pdev); 602 603 di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN; 604 605 return 0; 606} 607 608static int ds2760_battery_resume(struct platform_device *pdev) 609{ 610 struct ds2760_device_info *di = platform_get_drvdata(pdev); 611 612 di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN; 613 power_supply_changed(&di->bat); 614 615 cancel_delayed_work(&di->monitor_work); 616 queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ); 617 618 return 0; 619} 620 621#else 622 623#define ds2760_battery_suspend NULL 624#define ds2760_battery_resume NULL 625 626#endif /* CONFIG_PM */ 627 628MODULE_ALIAS("platform:ds2760-battery"); 629 630static struct platform_driver ds2760_battery_driver = { 631 .driver = { 632 .name = "ds2760-battery", 633 }, 634 .probe = ds2760_battery_probe, 635 .remove = ds2760_battery_remove, 636 .suspend = ds2760_battery_suspend, 637 .resume = ds2760_battery_resume, 638}; 639 640static int __init ds2760_battery_init(void) 641{ 642 return platform_driver_register(&ds2760_battery_driver); 643} 644 645static void __exit ds2760_battery_exit(void) 646{ 647 platform_driver_unregister(&ds2760_battery_driver); 648} 649 650module_init(ds2760_battery_init); 651module_exit(ds2760_battery_exit); 652 653MODULE_LICENSE("GPL"); 654MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, " 655 "Matt Reimer <mreimer@vpop.net>, " 656 "Anton Vorontsov <cbou@mail.ru>"); 657MODULE_DESCRIPTION("ds2760 battery driver"); 658