linux/drivers/power/max17042_battery.c
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   1/*
   2 * Fuel gauge driver for Maxim 17042 / 8966 / 8997
   3 *  Note that Maxim 8966 and 8997 are mfd and this is its subdevice.
   4 *
   5 * Copyright (C) 2011 Samsung Electronics
   6 * MyungJoo Ham <myungjoo.ham@samsung.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21 *
  22 * This driver is based on max17040_battery.c
  23 */
  24
  25#include <linux/init.h>
  26#include <linux/module.h>
  27#include <linux/slab.h>
  28#include <linux/i2c.h>
  29#include <linux/delay.h>
  30#include <linux/interrupt.h>
  31#include <linux/pm.h>
  32#include <linux/mod_devicetable.h>
  33#include <linux/power_supply.h>
  34#include <linux/power/max17042_battery.h>
  35#include <linux/of.h>
  36
  37/* Status register bits */
  38#define STATUS_POR_BIT         (1 << 1)
  39#define STATUS_BST_BIT         (1 << 3)
  40#define STATUS_VMN_BIT         (1 << 8)
  41#define STATUS_TMN_BIT         (1 << 9)
  42#define STATUS_SMN_BIT         (1 << 10)
  43#define STATUS_BI_BIT          (1 << 11)
  44#define STATUS_VMX_BIT         (1 << 12)
  45#define STATUS_TMX_BIT         (1 << 13)
  46#define STATUS_SMX_BIT         (1 << 14)
  47#define STATUS_BR_BIT          (1 << 15)
  48
  49/* Interrupt mask bits */
  50#define CONFIG_ALRT_BIT_ENBL    (1 << 2)
  51#define STATUS_INTR_SOCMIN_BIT  (1 << 10)
  52#define STATUS_INTR_SOCMAX_BIT  (1 << 14)
  53
  54#define VFSOC0_LOCK             0x0000
  55#define VFSOC0_UNLOCK           0x0080
  56#define MODEL_UNLOCK1   0X0059
  57#define MODEL_UNLOCK2   0X00C4
  58#define MODEL_LOCK1             0X0000
  59#define MODEL_LOCK2             0X0000
  60
  61#define dQ_ACC_DIV      0x4
  62#define dP_ACC_100      0x1900
  63#define dP_ACC_200      0x3200
  64
  65#define MAX17042_IC_VERSION     0x0092
  66#define MAX17047_IC_VERSION     0x00AC  /* same for max17050 */
  67
  68struct max17042_chip {
  69        struct i2c_client *client;
  70        struct power_supply battery;
  71        enum max170xx_chip_type chip_type;
  72        struct max17042_platform_data *pdata;
  73        struct work_struct work;
  74        int    init_complete;
  75};
  76
  77static int max17042_write_reg(struct i2c_client *client, u8 reg, u16 value)
  78{
  79        int ret = i2c_smbus_write_word_data(client, reg, value);
  80
  81        if (ret < 0)
  82                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
  83
  84        return ret;
  85}
  86
  87static int max17042_read_reg(struct i2c_client *client, u8 reg)
  88{
  89        int ret = i2c_smbus_read_word_data(client, reg);
  90
  91        if (ret < 0)
  92                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
  93
  94        return ret;
  95}
  96
  97static void max17042_set_reg(struct i2c_client *client,
  98                             struct max17042_reg_data *data, int size)
  99{
 100        int i;
 101
 102        for (i = 0; i < size; i++)
 103                max17042_write_reg(client, data[i].addr, data[i].data);
 104}
 105
 106static enum power_supply_property max17042_battery_props[] = {
 107        POWER_SUPPLY_PROP_PRESENT,
 108        POWER_SUPPLY_PROP_CYCLE_COUNT,
 109        POWER_SUPPLY_PROP_VOLTAGE_MAX,
 110        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 111        POWER_SUPPLY_PROP_VOLTAGE_NOW,
 112        POWER_SUPPLY_PROP_VOLTAGE_AVG,
 113        POWER_SUPPLY_PROP_VOLTAGE_OCV,
 114        POWER_SUPPLY_PROP_CAPACITY,
 115        POWER_SUPPLY_PROP_CHARGE_FULL,
 116        POWER_SUPPLY_PROP_CHARGE_COUNTER,
 117        POWER_SUPPLY_PROP_TEMP,
 118        POWER_SUPPLY_PROP_CURRENT_NOW,
 119        POWER_SUPPLY_PROP_CURRENT_AVG,
 120};
 121
 122static int max17042_get_property(struct power_supply *psy,
 123                            enum power_supply_property psp,
 124                            union power_supply_propval *val)
 125{
 126        struct max17042_chip *chip = container_of(psy,
 127                                struct max17042_chip, battery);
 128        int ret;
 129
 130        if (!chip->init_complete)
 131                return -EAGAIN;
 132
 133        switch (psp) {
 134        case POWER_SUPPLY_PROP_PRESENT:
 135                ret = max17042_read_reg(chip->client, MAX17042_STATUS);
 136                if (ret < 0)
 137                        return ret;
 138
 139                if (ret & MAX17042_STATUS_BattAbsent)
 140                        val->intval = 0;
 141                else
 142                        val->intval = 1;
 143                break;
 144        case POWER_SUPPLY_PROP_CYCLE_COUNT:
 145                ret = max17042_read_reg(chip->client, MAX17042_Cycles);
 146                if (ret < 0)
 147                        return ret;
 148
 149                val->intval = ret;
 150                break;
 151        case POWER_SUPPLY_PROP_VOLTAGE_MAX:
 152                ret = max17042_read_reg(chip->client, MAX17042_MinMaxVolt);
 153                if (ret < 0)
 154                        return ret;
 155
 156                val->intval = ret >> 8;
 157                val->intval *= 20000; /* Units of LSB = 20mV */
 158                break;
 159        case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 160                if (chip->chip_type == MAX17042)
 161                        ret = max17042_read_reg(chip->client, MAX17042_V_empty);
 162                else
 163                        ret = max17042_read_reg(chip->client, MAX17047_V_empty);
 164                if (ret < 0)
 165                        return ret;
 166
 167                val->intval = ret >> 7;
 168                val->intval *= 10000; /* Units of LSB = 10mV */
 169                break;
 170        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 171                ret = max17042_read_reg(chip->client, MAX17042_VCELL);
 172                if (ret < 0)
 173                        return ret;
 174
 175                val->intval = ret * 625 / 8;
 176                break;
 177        case POWER_SUPPLY_PROP_VOLTAGE_AVG:
 178                ret = max17042_read_reg(chip->client, MAX17042_AvgVCELL);
 179                if (ret < 0)
 180                        return ret;
 181
 182                val->intval = ret * 625 / 8;
 183                break;
 184        case POWER_SUPPLY_PROP_VOLTAGE_OCV:
 185                ret = max17042_read_reg(chip->client, MAX17042_OCVInternal);
 186                if (ret < 0)
 187                        return ret;
 188
 189                val->intval = ret * 625 / 8;
 190                break;
 191        case POWER_SUPPLY_PROP_CAPACITY:
 192                ret = max17042_read_reg(chip->client, MAX17042_RepSOC);
 193                if (ret < 0)
 194                        return ret;
 195
 196                val->intval = ret >> 8;
 197                break;
 198        case POWER_SUPPLY_PROP_CHARGE_FULL:
 199                ret = max17042_read_reg(chip->client, MAX17042_FullCAP);
 200                if (ret < 0)
 201                        return ret;
 202
 203                val->intval = ret * 1000 / 2;
 204                break;
 205        case POWER_SUPPLY_PROP_CHARGE_COUNTER:
 206                ret = max17042_read_reg(chip->client, MAX17042_QH);
 207                if (ret < 0)
 208                        return ret;
 209
 210                val->intval = ret * 1000 / 2;
 211                break;
 212        case POWER_SUPPLY_PROP_TEMP:
 213                ret = max17042_read_reg(chip->client, MAX17042_TEMP);
 214                if (ret < 0)
 215                        return ret;
 216
 217                val->intval = ret;
 218                /* The value is signed. */
 219                if (val->intval & 0x8000) {
 220                        val->intval = (0x7fff & ~val->intval) + 1;
 221                        val->intval *= -1;
 222                }
 223                /* The value is converted into deci-centigrade scale */
 224                /* Units of LSB = 1 / 256 degree Celsius */
 225                val->intval = val->intval * 10 / 256;
 226                break;
 227        case POWER_SUPPLY_PROP_CURRENT_NOW:
 228                if (chip->pdata->enable_current_sense) {
 229                        ret = max17042_read_reg(chip->client, MAX17042_Current);
 230                        if (ret < 0)
 231                                return ret;
 232
 233                        val->intval = ret;
 234                        if (val->intval & 0x8000) {
 235                                /* Negative */
 236                                val->intval = ~val->intval & 0x7fff;
 237                                val->intval++;
 238                                val->intval *= -1;
 239                        }
 240                        val->intval *= 1562500 / chip->pdata->r_sns;
 241                } else {
 242                        return -EINVAL;
 243                }
 244                break;
 245        case POWER_SUPPLY_PROP_CURRENT_AVG:
 246                if (chip->pdata->enable_current_sense) {
 247                        ret = max17042_read_reg(chip->client,
 248                                                MAX17042_AvgCurrent);
 249                        if (ret < 0)
 250                                return ret;
 251
 252                        val->intval = ret;
 253                        if (val->intval & 0x8000) {
 254                                /* Negative */
 255                                val->intval = ~val->intval & 0x7fff;
 256                                val->intval++;
 257                                val->intval *= -1;
 258                        }
 259                        val->intval *= 1562500 / chip->pdata->r_sns;
 260                } else {
 261                        return -EINVAL;
 262                }
 263                break;
 264        default:
 265                return -EINVAL;
 266        }
 267        return 0;
 268}
 269
 270static int max17042_write_verify_reg(struct i2c_client *client,
 271                                u8 reg, u16 value)
 272{
 273        int retries = 8;
 274        int ret;
 275        u16 read_value;
 276
 277        do {
 278                ret = i2c_smbus_write_word_data(client, reg, value);
 279                read_value =  max17042_read_reg(client, reg);
 280                if (read_value != value) {
 281                        ret = -EIO;
 282                        retries--;
 283                }
 284        } while (retries && read_value != value);
 285
 286        if (ret < 0)
 287                dev_err(&client->dev, "%s: err %d\n", __func__, ret);
 288
 289        return ret;
 290}
 291
 292static inline void max17042_override_por(
 293        struct i2c_client *client, u8 reg, u16 value)
 294{
 295        if (value)
 296                max17042_write_reg(client, reg, value);
 297}
 298
 299static inline void max10742_unlock_model(struct max17042_chip *chip)
 300{
 301        struct i2c_client *client = chip->client;
 302        max17042_write_reg(client, MAX17042_MLOCKReg1, MODEL_UNLOCK1);
 303        max17042_write_reg(client, MAX17042_MLOCKReg2, MODEL_UNLOCK2);
 304}
 305
 306static inline void max10742_lock_model(struct max17042_chip *chip)
 307{
 308        struct i2c_client *client = chip->client;
 309        max17042_write_reg(client, MAX17042_MLOCKReg1, MODEL_LOCK1);
 310        max17042_write_reg(client, MAX17042_MLOCKReg2, MODEL_LOCK2);
 311}
 312
 313static inline void max17042_write_model_data(struct max17042_chip *chip,
 314                                        u8 addr, int size)
 315{
 316        struct i2c_client *client = chip->client;
 317        int i;
 318        for (i = 0; i < size; i++)
 319                max17042_write_reg(client, addr + i,
 320                                chip->pdata->config_data->cell_char_tbl[i]);
 321}
 322
 323static inline void max17042_read_model_data(struct max17042_chip *chip,
 324                                        u8 addr, u16 *data, int size)
 325{
 326        struct i2c_client *client = chip->client;
 327        int i;
 328
 329        for (i = 0; i < size; i++)
 330                data[i] = max17042_read_reg(client, addr + i);
 331}
 332
 333static inline int max17042_model_data_compare(struct max17042_chip *chip,
 334                                        u16 *data1, u16 *data2, int size)
 335{
 336        int i;
 337
 338        if (memcmp(data1, data2, size)) {
 339                dev_err(&chip->client->dev, "%s compare failed\n", __func__);
 340                for (i = 0; i < size; i++)
 341                        dev_info(&chip->client->dev, "0x%x, 0x%x",
 342                                data1[i], data2[i]);
 343                dev_info(&chip->client->dev, "\n");
 344                return -EINVAL;
 345        }
 346        return 0;
 347}
 348
 349static int max17042_init_model(struct max17042_chip *chip)
 350{
 351        int ret;
 352        int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
 353        u16 *temp_data;
 354
 355        temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
 356        if (!temp_data)
 357                return -ENOMEM;
 358
 359        max10742_unlock_model(chip);
 360        max17042_write_model_data(chip, MAX17042_MODELChrTbl,
 361                                table_size);
 362        max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
 363                                table_size);
 364
 365        ret = max17042_model_data_compare(
 366                chip,
 367                chip->pdata->config_data->cell_char_tbl,
 368                temp_data,
 369                table_size);
 370
 371        max10742_lock_model(chip);
 372        kfree(temp_data);
 373
 374        return ret;
 375}
 376
 377static int max17042_verify_model_lock(struct max17042_chip *chip)
 378{
 379        int i;
 380        int table_size = ARRAY_SIZE(chip->pdata->config_data->cell_char_tbl);
 381        u16 *temp_data;
 382        int ret = 0;
 383
 384        temp_data = kcalloc(table_size, sizeof(*temp_data), GFP_KERNEL);
 385        if (!temp_data)
 386                return -ENOMEM;
 387
 388        max17042_read_model_data(chip, MAX17042_MODELChrTbl, temp_data,
 389                                table_size);
 390        for (i = 0; i < table_size; i++)
 391                if (temp_data[i])
 392                        ret = -EINVAL;
 393
 394        kfree(temp_data);
 395        return ret;
 396}
 397
 398static void max17042_write_config_regs(struct max17042_chip *chip)
 399{
 400        struct max17042_config_data *config = chip->pdata->config_data;
 401
 402        max17042_write_reg(chip->client, MAX17042_CONFIG, config->config);
 403        max17042_write_reg(chip->client, MAX17042_LearnCFG, config->learn_cfg);
 404        max17042_write_reg(chip->client, MAX17042_FilterCFG,
 405                        config->filter_cfg);
 406        max17042_write_reg(chip->client, MAX17042_RelaxCFG, config->relax_cfg);
 407        if (chip->chip_type == MAX17047)
 408                max17042_write_reg(chip->client, MAX17047_FullSOCThr,
 409                                                config->full_soc_thresh);
 410}
 411
 412static void  max17042_write_custom_regs(struct max17042_chip *chip)
 413{
 414        struct max17042_config_data *config = chip->pdata->config_data;
 415
 416        max17042_write_verify_reg(chip->client, MAX17042_RCOMP0,
 417                                config->rcomp0);
 418        max17042_write_verify_reg(chip->client, MAX17042_TempCo,
 419                                config->tcompc0);
 420        max17042_write_verify_reg(chip->client, MAX17042_ICHGTerm,
 421                                config->ichgt_term);
 422        if (chip->chip_type == MAX17042) {
 423                max17042_write_reg(chip->client, MAX17042_EmptyTempCo,
 424                                        config->empty_tempco);
 425                max17042_write_verify_reg(chip->client, MAX17042_K_empty0,
 426                                        config->kempty0);
 427        } else {
 428                max17042_write_verify_reg(chip->client, MAX17047_QRTbl00,
 429                                                config->qrtbl00);
 430                max17042_write_verify_reg(chip->client, MAX17047_QRTbl10,
 431                                                config->qrtbl10);
 432                max17042_write_verify_reg(chip->client, MAX17047_QRTbl20,
 433                                                config->qrtbl20);
 434                max17042_write_verify_reg(chip->client, MAX17047_QRTbl30,
 435                                                config->qrtbl30);
 436        }
 437}
 438
 439static void max17042_update_capacity_regs(struct max17042_chip *chip)
 440{
 441        struct max17042_config_data *config = chip->pdata->config_data;
 442
 443        max17042_write_verify_reg(chip->client, MAX17042_FullCAP,
 444                                config->fullcap);
 445        max17042_write_reg(chip->client, MAX17042_DesignCap,
 446                        config->design_cap);
 447        max17042_write_verify_reg(chip->client, MAX17042_FullCAPNom,
 448                                config->fullcapnom);
 449}
 450
 451static void max17042_reset_vfsoc0_reg(struct max17042_chip *chip)
 452{
 453        u16 vfSoc;
 454
 455        vfSoc = max17042_read_reg(chip->client, MAX17042_VFSOC);
 456        max17042_write_reg(chip->client, MAX17042_VFSOC0Enable, VFSOC0_UNLOCK);
 457        max17042_write_verify_reg(chip->client, MAX17042_VFSOC0, vfSoc);
 458        max17042_write_reg(chip->client, MAX17042_VFSOC0Enable, VFSOC0_LOCK);
 459}
 460
 461static void max17042_load_new_capacity_params(struct max17042_chip *chip)
 462{
 463        u16 full_cap0, rep_cap, dq_acc, vfSoc;
 464        u32 rem_cap;
 465
 466        struct max17042_config_data *config = chip->pdata->config_data;
 467
 468        full_cap0 = max17042_read_reg(chip->client, MAX17042_FullCAP0);
 469        vfSoc = max17042_read_reg(chip->client, MAX17042_VFSOC);
 470
 471        /* fg_vfSoc needs to shifted by 8 bits to get the
 472         * perc in 1% accuracy, to get the right rem_cap multiply
 473         * full_cap0, fg_vfSoc and devide by 100
 474         */
 475        rem_cap = ((vfSoc >> 8) * full_cap0) / 100;
 476        max17042_write_verify_reg(chip->client, MAX17042_RemCap, (u16)rem_cap);
 477
 478        rep_cap = (u16)rem_cap;
 479        max17042_write_verify_reg(chip->client, MAX17042_RepCap, rep_cap);
 480
 481        /* Write dQ_acc to 200% of Capacity and dP_acc to 200% */
 482        dq_acc = config->fullcap / dQ_ACC_DIV;
 483        max17042_write_verify_reg(chip->client, MAX17042_dQacc, dq_acc);
 484        max17042_write_verify_reg(chip->client, MAX17042_dPacc, dP_ACC_200);
 485
 486        max17042_write_verify_reg(chip->client, MAX17042_FullCAP,
 487                        config->fullcap);
 488        max17042_write_reg(chip->client, MAX17042_DesignCap,
 489                        config->design_cap);
 490        max17042_write_verify_reg(chip->client, MAX17042_FullCAPNom,
 491                        config->fullcapnom);
 492        /* Update SOC register with new SOC */
 493        max17042_write_reg(chip->client, MAX17042_RepSOC, vfSoc);
 494}
 495
 496/*
 497 * Block write all the override values coming from platform data.
 498 * This function MUST be called before the POR initialization proceedure
 499 * specified by maxim.
 500 */
 501static inline void max17042_override_por_values(struct max17042_chip *chip)
 502{
 503        struct i2c_client *client = chip->client;
 504        struct max17042_config_data *config = chip->pdata->config_data;
 505
 506        max17042_override_por(client, MAX17042_TGAIN, config->tgain);
 507        max17042_override_por(client, MAx17042_TOFF, config->toff);
 508        max17042_override_por(client, MAX17042_CGAIN, config->cgain);
 509        max17042_override_por(client, MAX17042_COFF, config->coff);
 510
 511        max17042_override_por(client, MAX17042_VALRT_Th, config->valrt_thresh);
 512        max17042_override_por(client, MAX17042_TALRT_Th, config->talrt_thresh);
 513        max17042_override_por(client, MAX17042_SALRT_Th,
 514                        config->soc_alrt_thresh);
 515        max17042_override_por(client, MAX17042_CONFIG, config->config);
 516        max17042_override_por(client, MAX17042_SHDNTIMER, config->shdntimer);
 517
 518        max17042_override_por(client, MAX17042_DesignCap, config->design_cap);
 519        max17042_override_por(client, MAX17042_ICHGTerm, config->ichgt_term);
 520
 521        max17042_override_por(client, MAX17042_AtRate, config->at_rate);
 522        max17042_override_por(client, MAX17042_LearnCFG, config->learn_cfg);
 523        max17042_override_por(client, MAX17042_FilterCFG, config->filter_cfg);
 524        max17042_override_por(client, MAX17042_RelaxCFG, config->relax_cfg);
 525        max17042_override_por(client, MAX17042_MiscCFG, config->misc_cfg);
 526        max17042_override_por(client, MAX17042_MaskSOC, config->masksoc);
 527
 528        max17042_override_por(client, MAX17042_FullCAP, config->fullcap);
 529        max17042_override_por(client, MAX17042_FullCAPNom, config->fullcapnom);
 530        if (chip->chip_type == MAX17042)
 531                max17042_override_por(client, MAX17042_SOC_empty,
 532                                                config->socempty);
 533        max17042_override_por(client, MAX17042_LAvg_empty, config->lavg_empty);
 534        max17042_override_por(client, MAX17042_dQacc, config->dqacc);
 535        max17042_override_por(client, MAX17042_dPacc, config->dpacc);
 536
 537        if (chip->chip_type == MAX17042)
 538                max17042_override_por(client, MAX17042_V_empty, config->vempty);
 539        else
 540                max17042_override_por(client, MAX17047_V_empty, config->vempty);
 541        max17042_override_por(client, MAX17042_TempNom, config->temp_nom);
 542        max17042_override_por(client, MAX17042_TempLim, config->temp_lim);
 543        max17042_override_por(client, MAX17042_FCTC, config->fctc);
 544        max17042_override_por(client, MAX17042_RCOMP0, config->rcomp0);
 545        max17042_override_por(client, MAX17042_TempCo, config->tcompc0);
 546        if (chip->chip_type) {
 547                max17042_override_por(client, MAX17042_EmptyTempCo,
 548                                        config->empty_tempco);
 549                max17042_override_por(client, MAX17042_K_empty0,
 550                                        config->kempty0);
 551        }
 552}
 553
 554static int max17042_init_chip(struct max17042_chip *chip)
 555{
 556        int ret;
 557        int val;
 558
 559        max17042_override_por_values(chip);
 560        /* After Power up, the MAX17042 requires 500mS in order
 561         * to perform signal debouncing and initial SOC reporting
 562         */
 563        msleep(500);
 564
 565        /* Initialize configaration */
 566        max17042_write_config_regs(chip);
 567
 568        /* write cell characterization data */
 569        ret = max17042_init_model(chip);
 570        if (ret) {
 571                dev_err(&chip->client->dev, "%s init failed\n",
 572                        __func__);
 573                return -EIO;
 574        }
 575        max17042_verify_model_lock(chip);
 576        if (ret) {
 577                dev_err(&chip->client->dev, "%s lock verify failed\n",
 578                        __func__);
 579                return -EIO;
 580        }
 581        /* write custom parameters */
 582        max17042_write_custom_regs(chip);
 583
 584        /* update capacity params */
 585        max17042_update_capacity_regs(chip);
 586
 587        /* delay must be atleast 350mS to allow VFSOC
 588         * to be calculated from the new configuration
 589         */
 590        msleep(350);
 591
 592        /* reset vfsoc0 reg */
 593        max17042_reset_vfsoc0_reg(chip);
 594
 595        /* load new capacity params */
 596        max17042_load_new_capacity_params(chip);
 597
 598        /* Init complete, Clear the POR bit */
 599        val = max17042_read_reg(chip->client, MAX17042_STATUS);
 600        max17042_write_reg(chip->client, MAX17042_STATUS,
 601                        val & (~STATUS_POR_BIT));
 602        return 0;
 603}
 604
 605static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off)
 606{
 607        u16 soc, soc_tr;
 608
 609        /* program interrupt thesholds such that we should
 610         * get interrupt for every 'off' perc change in the soc
 611         */
 612        soc = max17042_read_reg(chip->client, MAX17042_RepSOC) >> 8;
 613        soc_tr = (soc + off) << 8;
 614        soc_tr |= (soc - off);
 615        max17042_write_reg(chip->client, MAX17042_SALRT_Th, soc_tr);
 616}
 617
 618static irqreturn_t max17042_thread_handler(int id, void *dev)
 619{
 620        struct max17042_chip *chip = dev;
 621        u16 val;
 622
 623        val = max17042_read_reg(chip->client, MAX17042_STATUS);
 624        if ((val & STATUS_INTR_SOCMIN_BIT) ||
 625                (val & STATUS_INTR_SOCMAX_BIT)) {
 626                dev_info(&chip->client->dev, "SOC threshold INTR\n");
 627                max17042_set_soc_threshold(chip, 1);
 628        }
 629
 630        power_supply_changed(&chip->battery);
 631        return IRQ_HANDLED;
 632}
 633
 634static void max17042_init_worker(struct work_struct *work)
 635{
 636        struct max17042_chip *chip = container_of(work,
 637                                struct max17042_chip, work);
 638        int ret;
 639
 640        /* Initialize registers according to values from the platform data */
 641        if (chip->pdata->enable_por_init && chip->pdata->config_data) {
 642                ret = max17042_init_chip(chip);
 643                if (ret)
 644                        return;
 645        }
 646
 647        chip->init_complete = 1;
 648}
 649
 650#ifdef CONFIG_OF
 651static struct max17042_platform_data *
 652max17042_get_pdata(struct device *dev)
 653{
 654        struct device_node *np = dev->of_node;
 655        u32 prop;
 656        struct max17042_platform_data *pdata;
 657
 658        if (!np)
 659                return dev->platform_data;
 660
 661        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 662        if (!pdata)
 663                return NULL;
 664
 665        /*
 666         * Require current sense resistor value to be specified for
 667         * current-sense functionality to be enabled at all.
 668         */
 669        if (of_property_read_u32(np, "maxim,rsns-microohm", &prop) == 0) {
 670                pdata->r_sns = prop;
 671                pdata->enable_current_sense = true;
 672        }
 673
 674        return pdata;
 675}
 676#else
 677static struct max17042_platform_data *
 678max17042_get_pdata(struct device *dev)
 679{
 680        return dev->platform_data;
 681}
 682#endif
 683
 684static int __devinit max17042_probe(struct i2c_client *client,
 685                        const struct i2c_device_id *id)
 686{
 687        struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 688        struct max17042_chip *chip;
 689        int ret;
 690        int reg;
 691
 692        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
 693                return -EIO;
 694
 695        chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 696        if (!chip)
 697                return -ENOMEM;
 698
 699        chip->client = client;
 700        chip->pdata = max17042_get_pdata(&client->dev);
 701        if (!chip->pdata) {
 702                dev_err(&client->dev, "no platform data provided\n");
 703                return -EINVAL;
 704        }
 705
 706        i2c_set_clientdata(client, chip);
 707
 708        ret = max17042_read_reg(chip->client, MAX17042_DevName);
 709        if (ret == MAX17042_IC_VERSION) {
 710                dev_dbg(&client->dev, "chip type max17042 detected\n");
 711                chip->chip_type = MAX17042;
 712        } else if (ret == MAX17047_IC_VERSION) {
 713                dev_dbg(&client->dev, "chip type max17047/50 detected\n");
 714                chip->chip_type = MAX17047;
 715        } else {
 716                dev_err(&client->dev, "device version mismatch: %x\n", ret);
 717                return -EIO;
 718        }
 719
 720        chip->battery.name              = "max170xx_battery";
 721        chip->battery.type              = POWER_SUPPLY_TYPE_BATTERY;
 722        chip->battery.get_property      = max17042_get_property;
 723        chip->battery.properties        = max17042_battery_props;
 724        chip->battery.num_properties    = ARRAY_SIZE(max17042_battery_props);
 725
 726        /* When current is not measured,
 727         * CURRENT_NOW and CURRENT_AVG properties should be invisible. */
 728        if (!chip->pdata->enable_current_sense)
 729                chip->battery.num_properties -= 2;
 730
 731        if (chip->pdata->r_sns == 0)
 732                chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR;
 733
 734        if (chip->pdata->init_data)
 735                max17042_set_reg(client, chip->pdata->init_data,
 736                                chip->pdata->num_init_data);
 737
 738        if (!chip->pdata->enable_current_sense) {
 739                max17042_write_reg(client, MAX17042_CGAIN, 0x0000);
 740                max17042_write_reg(client, MAX17042_MiscCFG, 0x0003);
 741                max17042_write_reg(client, MAX17042_LearnCFG, 0x0007);
 742        }
 743
 744        ret = power_supply_register(&client->dev, &chip->battery);
 745        if (ret) {
 746                dev_err(&client->dev, "failed: power supply register\n");
 747                return ret;
 748        }
 749
 750        if (client->irq) {
 751                ret = request_threaded_irq(client->irq, NULL,
 752                                                max17042_thread_handler,
 753                                                IRQF_TRIGGER_FALLING,
 754                                                chip->battery.name, chip);
 755                if (!ret) {
 756                        reg =  max17042_read_reg(client, MAX17042_CONFIG);
 757                        reg |= CONFIG_ALRT_BIT_ENBL;
 758                        max17042_write_reg(client, MAX17042_CONFIG, reg);
 759                        max17042_set_soc_threshold(chip, 1);
 760                } else {
 761                        client->irq = 0;
 762                        dev_err(&client->dev, "%s(): cannot get IRQ\n",
 763                                __func__);
 764                }
 765        }
 766
 767        reg = max17042_read_reg(chip->client, MAX17042_STATUS);
 768        if (reg & STATUS_POR_BIT) {
 769                INIT_WORK(&chip->work, max17042_init_worker);
 770                schedule_work(&chip->work);
 771        } else {
 772                chip->init_complete = 1;
 773        }
 774
 775        return 0;
 776}
 777
 778static int __devexit max17042_remove(struct i2c_client *client)
 779{
 780        struct max17042_chip *chip = i2c_get_clientdata(client);
 781
 782        if (client->irq)
 783                free_irq(client->irq, chip);
 784        power_supply_unregister(&chip->battery);
 785        return 0;
 786}
 787
 788#ifdef CONFIG_PM
 789static int max17042_suspend(struct device *dev)
 790{
 791        struct max17042_chip *chip = dev_get_drvdata(dev);
 792
 793        /*
 794         * disable the irq and enable irq_wake
 795         * capability to the interrupt line.
 796         */
 797        if (chip->client->irq) {
 798                disable_irq(chip->client->irq);
 799                enable_irq_wake(chip->client->irq);
 800        }
 801
 802        return 0;
 803}
 804
 805static int max17042_resume(struct device *dev)
 806{
 807        struct max17042_chip *chip = dev_get_drvdata(dev);
 808
 809        if (chip->client->irq) {
 810                disable_irq_wake(chip->client->irq);
 811                enable_irq(chip->client->irq);
 812                /* re-program the SOC thresholds to 1% change */
 813                max17042_set_soc_threshold(chip, 1);
 814        }
 815
 816        return 0;
 817}
 818
 819static const struct dev_pm_ops max17042_pm_ops = {
 820        .suspend        = max17042_suspend,
 821        .resume         = max17042_resume,
 822};
 823
 824#define MAX17042_PM_OPS (&max17042_pm_ops)
 825#else
 826#define MAX17042_PM_OPS NULL
 827#endif
 828
 829#ifdef CONFIG_OF
 830static const struct of_device_id max17042_dt_match[] = {
 831        { .compatible = "maxim,max17042" },
 832        { .compatible = "maxim,max17047" },
 833        { .compatible = "maxim,max17050" },
 834        { },
 835};
 836MODULE_DEVICE_TABLE(of, max17042_dt_match);
 837#endif
 838
 839static const struct i2c_device_id max17042_id[] = {
 840        { "max17042", 0 },
 841        { "max17047", 1 },
 842        { "max17050", 2 },
 843        { }
 844};
 845MODULE_DEVICE_TABLE(i2c, max17042_id);
 846
 847static struct i2c_driver max17042_i2c_driver = {
 848        .driver = {
 849                .name   = "max17042",
 850                .of_match_table = of_match_ptr(max17042_dt_match),
 851                .pm     = MAX17042_PM_OPS,
 852        },
 853        .probe          = max17042_probe,
 854        .remove         = __devexit_p(max17042_remove),
 855        .id_table       = max17042_id,
 856};
 857module_i2c_driver(max17042_i2c_driver);
 858
 859MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
 860MODULE_DESCRIPTION("MAX17042 Fuel Gauge");
 861MODULE_LICENSE("GPL");
 862
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