drivers/power/supply/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 #include <linux/suspend.h>
  31 #include <linux/w1.h>
  32 #include <linux/of.h>
  33
  34 static unsigned int cache_time = 1000;
  35 module_param(cache_time, uint, 0644);
  36 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  37
  38 static bool pmod_enabled;
  39 module_param(pmod_enabled, bool, 0644);
  40 MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
  41
  42 static unsigned int rated_capacity;
  43 module_param(rated_capacity, uint, 0644);
  44 MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
  45
  46 static unsigned int current_accum;
  47 module_param(current_accum, uint, 0644);
  48 MODULE_PARM_DESC(current_accum, "current accumulator value");
  49
  50 #define W1_FAMILY_DS2760                0x30
  51
  52 /* Known commands to the DS2760 chip */
  53 #define W1_DS2760_SWAP                  0xAA
  54 #define W1_DS2760_READ_DATA             0x69
  55 #define W1_DS2760_WRITE_DATA            0x6C
  56 #define W1_DS2760_COPY_DATA             0x48
  57 #define W1_DS2760_RECALL_DATA           0xB8
  58 #define W1_DS2760_LOCK                  0x6A
  59
  60 /* Number of valid register addresses */
  61 #define DS2760_DATA_SIZE                0x40
  62
  63 #define DS2760_PROTECTION_REG           0x00
  64
  65 #define DS2760_STATUS_REG               0x01
  66 #define DS2760_STATUS_IE                (1 << 2)
  67 #define DS2760_STATUS_SWEN              (1 << 3)
  68 #define DS2760_STATUS_RNAOP             (1 << 4)
  69 #define DS2760_STATUS_PMOD              (1 << 5)
  70
  71 #define DS2760_EEPROM_REG               0x07
  72 #define DS2760_SPECIAL_FEATURE_REG      0x08
  73 #define DS2760_VOLTAGE_MSB              0x0c
  74 #define DS2760_VOLTAGE_LSB              0x0d
  75 #define DS2760_CURRENT_MSB              0x0e
  76 #define DS2760_CURRENT_LSB              0x0f
  77 #define DS2760_CURRENT_ACCUM_MSB        0x10
  78 #define DS2760_CURRENT_ACCUM_LSB        0x11
  79 #define DS2760_TEMP_MSB                 0x18
  80 #define DS2760_TEMP_LSB                 0x19
  81 #define DS2760_EEPROM_BLOCK0            0x20
  82 #define DS2760_ACTIVE_FULL              0x20
  83 #define DS2760_EEPROM_BLOCK1            0x30
  84 #define DS2760_STATUS_WRITE_REG         0x31
  85 #define DS2760_RATED_CAPACITY           0x32
  86 #define DS2760_CURRENT_OFFSET_BIAS      0x33
  87 #define DS2760_ACTIVE_EMPTY             0x3b
  88
  89 struct ds2760_device_info {
  90         struct device *dev;
  91
  92         /* DS2760 data, valid after calling ds2760_battery_read_status() */
  93         unsigned long update_time;      /* jiffies when data read */
  94         char raw[DS2760_DATA_SIZE];     /* raw DS2760 data */
  95         int voltage_raw;                /* units of 4.88 mV */
  96         int voltage_uV;                 /* units of µV */
  97         int current_raw;                /* units of 0.625 mA */
  98         int current_uA;                 /* units of µA */
  99         int accum_current_raw;          /* units of 0.25 mAh */
 100         int accum_current_uAh;          /* units of µAh */
 101         int temp_raw;                   /* units of 0.125 °C */
 102         int temp_C;                     /* units of 0.1 °C */
 103         int rated_capacity;             /* units of µAh */
 104         int rem_capacity;               /* percentage */
 105         int full_active_uAh;            /* units of µAh */
 106         int empty_uAh;                  /* units of µAh */
 107         int life_sec;                   /* units of seconds */
 108         int charge_status;              /* POWER_SUPPLY_STATUS_* */
 109
 110         int full_counter;
 111         struct power_supply *bat;
 112         struct power_supply_desc bat_desc;
 113         struct workqueue_struct *monitor_wqueue;
 114         struct delayed_work monitor_work;
 115         struct delayed_work set_charged_work;
 116         struct notifier_block pm_notifier;
 117 };
 118
 119 static int w1_ds2760_io(struct device *dev, char *buf, int addr, size_t count,
 120                         int io)
 121 {
 122         struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
 123
 124         if (!dev)
 125                 return 0;
 126
 127         mutex_lock(&sl->master->bus_mutex);
 128
 129         if (addr > DS2760_DATA_SIZE || addr < 0) {
 130                 count = 0;
 131                 goto out;
 132         }
 133         if (addr + count > DS2760_DATA_SIZE)
 134                 count = DS2760_DATA_SIZE - addr;
 135
 136         if (!w1_reset_select_slave(sl)) {
 137                 if (!io) {
 138                         w1_write_8(sl->master, W1_DS2760_READ_DATA);
 139                         w1_write_8(sl->master, addr);
 140                         count = w1_read_block(sl->master, buf, count);
 141                 } else {
 142                         w1_write_8(sl->master, W1_DS2760_WRITE_DATA);
 143                         w1_write_8(sl->master, addr);
 144                         w1_write_block(sl->master, buf, count);
 145                         /* XXX w1_write_block returns void, not n_written */
 146                 }
 147         }
 148
 149 out:
 150         mutex_unlock(&sl->master->bus_mutex);
 151
 152         return count;
 153 }
 154
 155 static int w1_ds2760_read(struct device *dev,
 156                           char *buf, int addr,
 157                           size_t count)
 158 {
 159         return w1_ds2760_io(dev, buf, addr, count, 0);
 160 }
 161
 162 static int w1_ds2760_write(struct device *dev,
 163                            char *buf,
 164                            int addr, size_t count)
 165 {
 166         return w1_ds2760_io(dev, buf, addr, count, 1);
 167 }
 168
 169 static int w1_ds2760_eeprom_cmd(struct device *dev, int addr, int cmd)
 170 {
 171         struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
 172
 173         if (!dev)
 174                 return -EINVAL;
 175
 176         mutex_lock(&sl->master->bus_mutex);
 177
 178         if (w1_reset_select_slave(sl) == 0) {
 179                 w1_write_8(sl->master, cmd);
 180                 w1_write_8(sl->master, addr);
 181         }
 182
 183         mutex_unlock(&sl->master->bus_mutex);
 184         return 0;
 185 }
 186
 187 static int w1_ds2760_store_eeprom(struct device *dev, int addr)
 188 {
 189         return w1_ds2760_eeprom_cmd(dev, addr, W1_DS2760_COPY_DATA);
 190 }
 191
 192 static int w1_ds2760_recall_eeprom(struct device *dev, int addr)
 193 {
 194         return w1_ds2760_eeprom_cmd(dev, addr, W1_DS2760_RECALL_DATA);
 195 }
 196
 197 static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
 198                              struct bin_attribute *bin_attr, char *buf,
 199                              loff_t off, size_t count)
 200 {
 201         struct device *dev = container_of(kobj, struct device, kobj);
 202         return w1_ds2760_read(dev, buf, off, count);
 203 }
 204
 205 static BIN_ATTR_RO(w1_slave, DS2760_DATA_SIZE);
 206
 207 static struct bin_attribute *w1_ds2760_bin_attrs[] = {
 208         &bin_attr_w1_slave,
 209         NULL,
 210 };
 211
 212 static const struct attribute_group w1_ds2760_group = {
 213         .bin_attrs = w1_ds2760_bin_attrs,
 214 };
 215
 216 static const struct attribute_group *w1_ds2760_groups[] = {
 217         &w1_ds2760_group,
 218         NULL,
 219 };
 220 /* Some batteries have their rated capacity stored a N * 10 mAh, while
 221  * others use an index into this table. */
 222 static int rated_capacities[] = {
 223         0,
 224         920,    /* Samsung */
 225         920,    /* BYD */
 226         920,    /* Lishen */
 227         920,    /* NEC */
 228         1440,   /* Samsung */
 229         1440,   /* BYD */
 230 #ifdef CONFIG_MACH_H4700
 231         1800,   /* HP iPAQ hx4700 3.7V 1800mAh (359113-001) */
 232 #else
 233         1440,   /* Lishen */
 234 #endif
 235         1440,   /* NEC */
 236         2880,   /* Samsung */
 237         2880,   /* BYD */
 238         2880,   /* Lishen */
 239         2880,   /* NEC */
 240 #ifdef CONFIG_MACH_H4700
 241         0,
 242         3600,   /* HP iPAQ hx4700 3.7V 3600mAh (359114-001) */
 243 #endif
 244 };
 245
 246 /* array is level at temps 0°C, 10°C, 20°C, 30°C, 40°C
 247  * temp is in Celsius */
 248 static int battery_interpolate(int array[], int temp)
 249 {
 250         int index, dt;
 251
 252         if (temp <= 0)
 253                 return array[0];
 254         if (temp >= 40)
 255                 return array[4];
 256
 257         index = temp / 10;
 258         dt    = temp % 10;
 259
 260         return array[index] + (((array[index + 1] - array[index]) * dt) / 10);
 261 }
 262
 263 static int ds2760_battery_read_status(struct ds2760_device_info *di)
 264 {
 265         int ret, i, start, count, scale[5];
 266
 267         if (di->update_time && time_before(jiffies, di->update_time +
 268                                            msecs_to_jiffies(cache_time)))
 269                 return 0;
 270
 271         /* The first time we read the entire contents of SRAM/EEPROM,
 272          * but after that we just read the interesting bits that change. */
 273         if (di->update_time == 0) {
 274                 start = 0;
 275                 count = DS2760_DATA_SIZE;
 276         } else {
 277                 start = DS2760_VOLTAGE_MSB;
 278                 count = DS2760_TEMP_LSB - start + 1;
 279         }
 280
 281         ret = w1_ds2760_read(di->dev, di->raw + start, start, count);
 282         if (ret != count) {
 283                 dev_warn(di->dev, "call to w1_ds2760_read failed (0x%p)\n",
 284                          di->dev);
 285                 return 1;
 286         }
 287
 288         di->update_time = jiffies;
 289
 290         /* DS2760 reports voltage in units of 4.88mV, but the battery class
 291          * reports in units of uV, so convert by multiplying by 4880. */
 292         di->voltage_raw = (di->raw[DS2760_VOLTAGE_MSB] << 3) |
 293                           (di->raw[DS2760_VOLTAGE_LSB] >> 5);
 294         di->voltage_uV = di->voltage_raw * 4880;
 295
 296         /* DS2760 reports current in signed units of 0.625mA, but the battery
 297          * class reports in units of µA, so convert by multiplying by 625. */
 298         di->current_raw =
 299             (((signed char)di->raw[DS2760_CURRENT_MSB]) << 5) |
 300                           (di->raw[DS2760_CURRENT_LSB] >> 3);
 301         di->current_uA = di->current_raw * 625;
 302
 303         /* DS2760 reports accumulated current in signed units of 0.25mAh. */
 304         di->accum_current_raw =
 305             (((signed char)di->raw[DS2760_CURRENT_ACCUM_MSB]) << 8) |
 306                            di->raw[DS2760_CURRENT_ACCUM_LSB];
 307         di->accum_current_uAh = di->accum_current_raw * 250;
 308
 309         /* DS2760 reports temperature in signed units of 0.125°C, but the
 310          * battery class reports in units of 1/10 °C, so we convert by
 311          * multiplying by .125 * 10 = 1.25. */
 312         di->temp_raw = (((signed char)di->raw[DS2760_TEMP_MSB]) << 3) |
 313                                      (di->raw[DS2760_TEMP_LSB] >> 5);
 314         di->temp_C = di->temp_raw + (di->temp_raw / 4);
 315
 316         /* At least some battery monitors (e.g. HP iPAQ) store the battery's
 317          * maximum rated capacity. */
 318         if (di->raw[DS2760_RATED_CAPACITY] < ARRAY_SIZE(rated_capacities))
 319                 di->rated_capacity = rated_capacities[
 320                         (unsigned int)di->raw[DS2760_RATED_CAPACITY]];
 321         else
 322                 di->rated_capacity = di->raw[DS2760_RATED_CAPACITY] * 10;
 323
 324         di->rated_capacity *= 1000; /* convert to µAh */
 325
 326         /* Calculate the full level at the present temperature. */
 327         di->full_active_uAh = di->raw[DS2760_ACTIVE_FULL] << 8 |
 328                               di->raw[DS2760_ACTIVE_FULL + 1];
 329
 330         /* If the full_active_uAh value is not given, fall back to the rated
 331          * capacity. This is likely to happen when chips are not part of the
 332          * battery pack and is therefore not bootstrapped. */
 333         if (di->full_active_uAh == 0)
 334                 di->full_active_uAh = di->rated_capacity / 1000L;
 335
 336         scale[0] = di->full_active_uAh;
 337         for (i = 1; i < 5; i++)
 338                 scale[i] = scale[i - 1] + di->raw[DS2760_ACTIVE_FULL + 1 + i];
 339
 340         di->full_active_uAh = battery_interpolate(scale, di->temp_C / 10);
 341         di->full_active_uAh *= 1000; /* convert to µAh */
 342
 343         /* Calculate the empty level at the present temperature. */
 344         scale[4] = di->raw[DS2760_ACTIVE_EMPTY + 4];
 345         for (i = 3; i >= 0; i--)
 346                 scale[i] = scale[i + 1] + di->raw[DS2760_ACTIVE_EMPTY + i];
 347
 348         di->empty_uAh = battery_interpolate(scale, di->temp_C / 10);
 349         di->empty_uAh *= 1000; /* convert to µAh */
 350
 351         if (di->full_active_uAh == di->empty_uAh)
 352                 di->rem_capacity = 0;
 353         else
 354                 /* From Maxim Application Note 131: remaining capacity =
 355                  * ((ICA - Empty Value) / (Full Value - Empty Value)) x 100% */
 356                 di->rem_capacity = ((di->accum_current_uAh - di->empty_uAh) * 100L) /
 357                                     (di->full_active_uAh - di->empty_uAh);
 358
 359         if (di->rem_capacity < 0)
 360                 di->rem_capacity = 0;
 361         if (di->rem_capacity > 100)
 362                 di->rem_capacity = 100;
 363
 364         if (di->current_uA < -100L)
 365                 di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
 366                                         / (di->current_uA / 100L);
 367         else
 368                 di->life_sec = 0;
 369
 370         return 0;
 371 }
 372
 373 static void ds2760_battery_set_current_accum(struct ds2760_device_info *di,
 374                                              unsigned int acr_val)
 375 {
 376         unsigned char acr[2];
 377
 378         /* acr is in units of 0.25 mAh */
 379         acr_val *= 4L;
 380         acr_val /= 1000;
 381
 382         acr[0] = acr_val >> 8;
 383         acr[1] = acr_val & 0xff;
 384
 385         if (w1_ds2760_write(di->dev, acr, DS2760_CURRENT_ACCUM_MSB, 2) < 2)
 386                 dev_warn(di->dev, "ACR write failed\n");
 387 }
 388
 389 static void ds2760_battery_update_status(struct ds2760_device_info *di)
 390 {
 391         int old_charge_status = di->charge_status;
 392
 393         ds2760_battery_read_status(di);
 394
 395         if (di->charge_status == POWER_SUPPLY_STATUS_UNKNOWN)
 396                 di->full_counter = 0;
 397
 398         if (power_supply_am_i_supplied(di->bat)) {
 399                 if (di->current_uA > 10000) {
 400                         di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
 401                         di->full_counter = 0;
 402                 } else if (di->current_uA < -5000) {
 403                         if (di->charge_status != POWER_SUPPLY_STATUS_NOT_CHARGING)
 404                                 dev_notice(di->dev, "not enough power to "
 405                                            "charge\n");
 406                         di->charge_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
 407                         di->full_counter = 0;
 408                 } else if (di->current_uA < 10000 &&
 409                             di->charge_status != POWER_SUPPLY_STATUS_FULL) {
 410
 411                         /* Don't consider the battery to be full unless
 412                          * we've seen the current < 10 mA at least two
 413                          * consecutive times. */
 414
 415                         di->full_counter++;
 416
 417                         if (di->full_counter < 2) {
 418                                 di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
 419                         } else {
 420                                 di->charge_status = POWER_SUPPLY_STATUS_FULL;
 421                                 ds2760_battery_set_current_accum(di,
 422                                                 di->full_active_uAh);
 423                         }
 424                 }
 425         } else {
 426                 di->charge_status = POWER_SUPPLY_STATUS_DISCHARGING;
 427                 di->full_counter = 0;
 428         }
 429
 430         if (di->charge_status != old_charge_status)
 431                 power_supply_changed(di->bat);
 432 }
 433
 434 static void ds2760_battery_write_status(struct ds2760_device_info *di,
 435                                         char status)
 436 {
 437         if (status == di->raw[DS2760_STATUS_REG])
 438                 return;
 439
 440         w1_ds2760_write(di->dev, &status, DS2760_STATUS_WRITE_REG, 1);
 441         w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
 442         w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
 443 }
 444
 445 static void ds2760_battery_write_rated_capacity(struct ds2760_device_info *di,
 446                                                 unsigned char rated_capacity)
 447 {
 448         if (rated_capacity == di->raw[DS2760_RATED_CAPACITY])
 449                 return;
 450
 451         w1_ds2760_write(di->dev, &rated_capacity, DS2760_RATED_CAPACITY, 1);
 452         w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
 453         w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
 454 }
 455
 456 static void ds2760_battery_write_active_full(struct ds2760_device_info *di,
 457                                              int active_full)
 458 {
 459         unsigned char tmp[2] = {
 460                 active_full >> 8,
 461                 active_full & 0xff
 462         };
 463
 464         if (tmp[0] == di->raw[DS2760_ACTIVE_FULL] &&
 465             tmp[1] == di->raw[DS2760_ACTIVE_FULL + 1])
 466                 return;
 467
 468         w1_ds2760_write(di->dev, tmp, DS2760_ACTIVE_FULL, sizeof(tmp));
 469         w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK0);
 470         w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK0);
 471
 472         /* Write to the di->raw[] buffer directly - the DS2760_ACTIVE_FULL
 473          * values won't be read back by ds2760_battery_read_status() */
 474         di->raw[DS2760_ACTIVE_FULL] = tmp[0];
 475         di->raw[DS2760_ACTIVE_FULL + 1] = tmp[1];
 476 }
 477
 478 static void ds2760_battery_work(struct work_struct *work)
 479 {
 480         struct ds2760_device_info *di = container_of(work,
 481                 struct ds2760_device_info, monitor_work.work);
 482         const int interval = HZ * 60;
 483
 484         dev_dbg(di->dev, "%s\n", __func__);
 485
 486         ds2760_battery_update_status(di);
 487         queue_delayed_work(di->monitor_wqueue, &di->monitor_work, interval);
 488 }
 489
 490 static void ds2760_battery_external_power_changed(struct power_supply *psy)
 491 {
 492         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 493
 494         dev_dbg(di->dev, "%s\n", __func__);
 495
 496         mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ/10);
 497 }
 498
 499
 500 static void ds2760_battery_set_charged_work(struct work_struct *work)
 501 {
 502         char bias;
 503         struct ds2760_device_info *di = container_of(work,
 504                 struct ds2760_device_info, set_charged_work.work);
 505
 506         dev_dbg(di->dev, "%s\n", __func__);
 507
 508         ds2760_battery_read_status(di);
 509
 510         /* When we get notified by external circuitry that the battery is
 511          * considered fully charged now, we know that there is no current
 512          * flow any more. However, the ds2760's internal current meter is
 513          * too inaccurate to rely on - spec say something ~15% failure.
 514          * Hence, we use the current offset bias register to compensate
 515          * that error.
 516          */
 517
 518         if (!power_supply_am_i_supplied(di->bat))
 519                 return;
 520
 521         bias = (signed char) di->current_raw +
 522                 (signed char) di->raw[DS2760_CURRENT_OFFSET_BIAS];
 523
 524         dev_dbg(di->dev, "%s: bias = %d\n", __func__, bias);
 525
 526         w1_ds2760_write(di->dev, &bias, DS2760_CURRENT_OFFSET_BIAS, 1);
 527         w1_ds2760_store_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
 528         w1_ds2760_recall_eeprom(di->dev, DS2760_EEPROM_BLOCK1);
 529
 530         /* Write to the di->raw[] buffer directly - the CURRENT_OFFSET_BIAS
 531          * value won't be read back by ds2760_battery_read_status() */
 532         di->raw[DS2760_CURRENT_OFFSET_BIAS] = bias;
 533 }
 534
 535 static void ds2760_battery_set_charged(struct power_supply *psy)
 536 {
 537         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 538
 539         /* postpone the actual work by 20 secs. This is for debouncing GPIO
 540          * signals and to let the current value settle. See AN4188. */
 541         mod_delayed_work(di->monitor_wqueue, &di->set_charged_work, HZ * 20);
 542 }
 543
 544 static int ds2760_battery_get_property(struct power_supply *psy,
 545                                        enum power_supply_property psp,
 546                                        union power_supply_propval *val)
 547 {
 548         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 549
 550         switch (psp) {
 551         case POWER_SUPPLY_PROP_STATUS:
 552                 val->intval = di->charge_status;
 553                 return 0;
 554         default:
 555                 break;
 556         }
 557
 558         ds2760_battery_read_status(di);
 559
 560         switch (psp) {
 561         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 562                 val->intval = di->voltage_uV;
 563                 break;
 564         case POWER_SUPPLY_PROP_CURRENT_NOW:
 565                 val->intval = di->current_uA;
 566                 break;
 567         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 568                 val->intval = di->rated_capacity;
 569                 break;
 570         case POWER_SUPPLY_PROP_CHARGE_FULL:
 571                 val->intval = di->full_active_uAh;
 572                 break;
 573         case POWER_SUPPLY_PROP_CHARGE_EMPTY:
 574                 val->intval = di->empty_uAh;
 575                 break;
 576         case POWER_SUPPLY_PROP_CHARGE_NOW:
 577                 val->intval = di->accum_current_uAh;
 578                 break;
 579         case POWER_SUPPLY_PROP_TEMP:
 580                 val->intval = di->temp_C;
 581                 break;
 582         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
 583                 val->intval = di->life_sec;
 584                 break;
 585         case POWER_SUPPLY_PROP_CAPACITY:
 586                 val->intval = di->rem_capacity;
 587                 break;
 588         default:
 589                 return -EINVAL;
 590         }
 591
 592         return 0;
 593 }
 594
 595 static int ds2760_battery_set_property(struct power_supply *psy,
 596                                        enum power_supply_property psp,
 597                                        const union power_supply_propval *val)
 598 {
 599         struct ds2760_device_info *di = power_supply_get_drvdata(psy);
 600
 601         switch (psp) {
 602         case POWER_SUPPLY_PROP_CHARGE_FULL:
 603                 /* the interface counts in uAh, convert the value */
 604                 ds2760_battery_write_active_full(di, val->intval / 1000L);
 605                 break;
 606
 607         case POWER_SUPPLY_PROP_CHARGE_NOW:
 608                 /* ds2760_battery_set_current_accum() does the conversion */
 609                 ds2760_battery_set_current_accum(di, val->intval);
 610                 break;
 611
 612         default:
 613                 return -EPERM;
 614         }
 615
 616         return 0;
 617 }
 618
 619 static int ds2760_battery_property_is_writeable(struct power_supply *psy,
 620                                                 enum power_supply_property psp)
 621 {
 622         switch (psp) {
 623         case POWER_SUPPLY_PROP_CHARGE_FULL:
 624         case POWER_SUPPLY_PROP_CHARGE_NOW:
 625                 return 1;
 626
 627         default:
 628                 break;
 629         }
 630
 631         return 0;
 632 }
 633
 634 static enum power_supply_property ds2760_battery_props[] = {
 635         POWER_SUPPLY_PROP_STATUS,
 636         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 637         POWER_SUPPLY_PROP_CURRENT_NOW,
 638         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 639         POWER_SUPPLY_PROP_CHARGE_FULL,
 640         POWER_SUPPLY_PROP_CHARGE_EMPTY,
 641         POWER_SUPPLY_PROP_CHARGE_NOW,
 642         POWER_SUPPLY_PROP_TEMP,
 643         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
 644         POWER_SUPPLY_PROP_CAPACITY,
 645 };
 646
 647 static int ds2760_pm_notifier(struct notifier_block *notifier,
 648                               unsigned long pm_event,
 649                               void *unused)
 650 {
 651         struct ds2760_device_info *di =
 652                 container_of(notifier, struct ds2760_device_info, pm_notifier);
 653
 654         switch (pm_event) {
 655         case PM_HIBERNATION_PREPARE:
 656         case PM_SUSPEND_PREPARE:
 657                 di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
 658                 break;
 659
 660         case PM_POST_RESTORE:
 661         case PM_POST_HIBERNATION:
 662         case PM_POST_SUSPEND:
 663                 di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
 664                 power_supply_changed(di->bat);
 665                 mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ);
 666
 667                 break;
 668
 669         case PM_RESTORE_PREPARE:
 670         default:
 671                 break;
 672         }
 673
 674         return NOTIFY_DONE;
 675 }
 676
 677 static int w1_ds2760_add_slave(struct w1_slave *sl)
 678 {
 679         struct power_supply_config psy_cfg = {};
 680         struct ds2760_device_info *di;
 681         struct device *dev = &sl->dev;
 682         int retval = 0;
 683         char name[32];
 684         char status;
 685
 686         di = devm_kzalloc(dev, sizeof(*di), GFP_KERNEL);
 687         if (!di) {
 688                 retval = -ENOMEM;
 689                 goto di_alloc_failed;
 690         }
 691
 692         snprintf(name, sizeof(name), "ds2760-battery.%d", dev->id);
 693
 694         di->dev                         = dev;
 695         di->bat_desc.name               = name;
 696         di->bat_desc.type               = POWER_SUPPLY_TYPE_BATTERY;
 697         di->bat_desc.properties         = ds2760_battery_props;
 698         di->bat_desc.num_properties     = ARRAY_SIZE(ds2760_battery_props);
 699         di->bat_desc.get_property       = ds2760_battery_get_property;
 700         di->bat_desc.set_property       = ds2760_battery_set_property;
 701         di->bat_desc.property_is_writeable =
 702                                   ds2760_battery_property_is_writeable;
 703         di->bat_desc.set_charged        = ds2760_battery_set_charged;
 704         di->bat_desc.external_power_changed =
 705                                   ds2760_battery_external_power_changed;
 706
 707         psy_cfg.drv_data = di;
 708
 709         if (dev->of_node) {
 710                 u32 tmp;
 711
 712                 psy_cfg.of_node = dev->of_node;
 713
 714                 if (!of_property_read_bool(dev->of_node, "maxim,pmod-enabled"))
 715                         pmod_enabled = true;
 716
 717                 if (!of_property_read_u32(dev->of_node,
 718                                           "maxim,cache-time-ms", &tmp))
 719                         cache_time = tmp;
 720
 721                 if (!of_property_read_u32(dev->of_node,
 722                                           "rated-capacity-microamp-hours",
 723                                           &tmp))
 724                         rated_capacity = tmp / 10; /* property is in mAh */
 725         }
 726
 727         di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
 728
 729         sl->family_data = di;
 730
 731         /* enable sleep mode feature */
 732         ds2760_battery_read_status(di);
 733         status = di->raw[DS2760_STATUS_REG];
 734         if (pmod_enabled)
 735                 status |= DS2760_STATUS_PMOD;
 736         else
 737                 status &= ~DS2760_STATUS_PMOD;
 738
 739         ds2760_battery_write_status(di, status);
 740
 741         /* set rated capacity from module param or device tree */
 742         if (rated_capacity)
 743                 ds2760_battery_write_rated_capacity(di, rated_capacity);
 744
 745         /* set current accumulator if given as parameter.
 746          * this should only be done for bootstrapping the value */
 747         if (current_accum)
 748                 ds2760_battery_set_current_accum(di, current_accum);
 749
 750         di->bat = power_supply_register(dev, &di->bat_desc, &psy_cfg);
 751         if (IS_ERR(di->bat)) {
 752                 dev_err(di->dev, "failed to register battery\n");
 753                 retval = PTR_ERR(di->bat);
 754                 goto batt_failed;
 755         }
 756
 757         INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work);
 758         INIT_DELAYED_WORK(&di->set_charged_work,
 759                           ds2760_battery_set_charged_work);
 760         di->monitor_wqueue = alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
 761         if (!di->monitor_wqueue) {
 762                 retval = -ESRCH;
 763                 goto workqueue_failed;
 764         }
 765         queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ * 1);
 766
 767         di->pm_notifier.notifier_call = ds2760_pm_notifier;
 768         register_pm_notifier(&di->pm_notifier);
 769
 770         goto success;
 771
 772 workqueue_failed:
 773         power_supply_unregister(di->bat);
 774 batt_failed:
 775 di_alloc_failed:
 776 success:
 777         return retval;
 778 }
 779
 780 static void w1_ds2760_remove_slave(struct w1_slave *sl)
 781 {
 782         struct ds2760_device_info *di = sl->family_data;
 783
 784         unregister_pm_notifier(&di->pm_notifier);
 785         cancel_delayed_work_sync(&di->monitor_work);
 786         cancel_delayed_work_sync(&di->set_charged_work);
 787         destroy_workqueue(di->monitor_wqueue);
 788         power_supply_unregister(di->bat);
 789 }
 790
 791 #ifdef CONFIG_OF
 792 static const struct of_device_id w1_ds2760_of_ids[] = {
 793         { .compatible = "maxim,ds2760" },
 794         {}
 795 };
 796 #endif
 797
 798 static struct w1_family_ops w1_ds2760_fops = {
 799         .add_slave      = w1_ds2760_add_slave,
 800         .remove_slave   = w1_ds2760_remove_slave,
 801         .groups         = w1_ds2760_groups,
 802 };
 803
 804 static struct w1_family w1_ds2760_family = {
 805         .fid            = W1_FAMILY_DS2760,
 806         .fops           = &w1_ds2760_fops,
 807         .of_match_table = of_match_ptr(w1_ds2760_of_ids),
 808 };
 809 module_w1_family(w1_ds2760_family);
 810
 811 MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
 812               "Matt Reimer <mreimer@vpop.net>, "
 813               "Anton Vorontsov <cbou@mail.ru>");
 814 MODULE_DESCRIPTION("1-wire Driver Dallas 2760 battery monitor chip");
 815 MODULE_LICENSE("GPL");
 816 MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2760));