linux/drivers/power/supply/ds2760_battery.c
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   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
  34static unsigned int cache_time = 1000;
  35module_param(cache_time, uint, 0644);
  36MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  37
  38static bool pmod_enabled;
  39module_param(pmod_enabled, bool, 0644);
  40MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
  41
  42static unsigned int rated_capacity;
  43module_param(rated_capacity, uint, 0644);
  44MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
  45
  46static unsigned int current_accum;
  47module_param(current_accum, uint, 0644);
  48MODULE_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
  89struct 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
 119static 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
 149out:
 150        mutex_unlock(&sl->master->bus_mutex);
 151
 152        return count;
 153}
 154
 155static 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
 162static 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
 169static 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
 187static 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
 192static 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
 197static 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
 205static BIN_ATTR_RO(w1_slave, DS2760_DATA_SIZE);
 206
 207static struct bin_attribute *w1_ds2760_bin_attrs[] = {
 208        &bin_attr_w1_slave,
 209        NULL,
 210};
 211
 212static const struct attribute_group w1_ds2760_group = {
 213        .bin_attrs = w1_ds2760_bin_attrs,
 214};
 215
 216static 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. */
 222static 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 */
 248static 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
 263static 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
 373static 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
 389static 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
 434static 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
 445static 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
 456static 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
 478static 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
 490static 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
 500static 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
 535static 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
 544static 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
 595static 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
 619static 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
 634static 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
 647static 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
 677static 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
 772workqueue_failed:
 773        power_supply_unregister(di->bat);
 774batt_failed:
 775di_alloc_failed:
 776success:
 777        return retval;
 778}
 779
 780static 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
 792static const struct of_device_id w1_ds2760_of_ids[] = {
 793        { .compatible = "maxim,ds2760" },
 794        {}
 795};
 796#endif
 797
 798static const 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
 804static 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};
 809module_w1_family(w1_ds2760_family);
 810
 811MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
 812              "Matt Reimer <mreimer@vpop.net>, "
 813              "Anton Vorontsov <cbou@mail.ru>");
 814MODULE_DESCRIPTION("1-wire Driver Dallas 2760 battery monitor chip");
 815MODULE_LICENSE("GPL");
 816MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2760));
 817