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
 576        ret = max17042_verify_model_lock(chip);
 577        if (ret) {
 578                dev_err(&chip->client->dev, "%s lock verify failed\n",
 579                        __func__);
 580                return -EIO;
 581        }
 582        /* write custom parameters */
 583        max17042_write_custom_regs(chip);
 584
 585        /* update capacity params */
 586        max17042_update_capacity_regs(chip);
 587
 588        /* delay must be atleast 350mS to allow VFSOC
 589         * to be calculated from the new configuration
 590         */
 591        msleep(350);
 592
 593        /* reset vfsoc0 reg */
 594        max17042_reset_vfsoc0_reg(chip);
 595
 596        /* load new capacity params */
 597        max17042_load_new_capacity_params(chip);
 598
 599        /* Init complete, Clear the POR bit */
 600        val = max17042_read_reg(chip->client, MAX17042_STATUS);
 601        max17042_write_reg(chip->client, MAX17042_STATUS,
 602                        val & (~STATUS_POR_BIT));
 603        return 0;
 604}
 605
 606static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off)
 607{
 608        u16 soc, soc_tr;
 609
 610        /* program interrupt thesholds such that we should
 611         * get interrupt for every 'off' perc change in the soc
 612         */
 613        soc = max17042_read_reg(chip->client, MAX17042_RepSOC) >> 8;
 614        soc_tr = (soc + off) << 8;
 615        soc_tr |= (soc - off);
 616        max17042_write_reg(chip->client, MAX17042_SALRT_Th, soc_tr);
 617}
 618
 619static irqreturn_t max17042_thread_handler(int id, void *dev)
 620{
 621        struct max17042_chip *chip = dev;
 622        u16 val;
 623
 624        val = max17042_read_reg(chip->client, MAX17042_STATUS);
 625        if ((val & STATUS_INTR_SOCMIN_BIT) ||
 626                (val & STATUS_INTR_SOCMAX_BIT)) {
 627                dev_info(&chip->client->dev, "SOC threshold INTR\n");
 628                max17042_set_soc_threshold(chip, 1);
 629        }
 630
 631        power_supply_changed(&chip->battery);
 632        return IRQ_HANDLED;
 633}
 634
 635static void max17042_init_worker(struct work_struct *work)
 636{
 637        struct max17042_chip *chip = container_of(work,
 638                                struct max17042_chip, work);
 639        int ret;
 640
 641        /* Initialize registers according to values from the platform data */
 642        if (chip->pdata->enable_por_init && chip->pdata->config_data) {
 643                ret = max17042_init_chip(chip);
 644                if (ret)
 645                        return;
 646        }
 647
 648        chip->init_complete = 1;
 649}
 650
 651#ifdef CONFIG_OF
 652static struct max17042_platform_data *
 653max17042_get_pdata(struct device *dev)
 654{
 655        struct device_node *np = dev->of_node;
 656        u32 prop;
 657        struct max17042_platform_data *pdata;
 658
 659        if (!np)
 660                return dev->platform_data;
 661
 662        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 663        if (!pdata)
 664                return NULL;
 665
 666        /*
 667         * Require current sense resistor value to be specified for
 668         * current-sense functionality to be enabled at all.
 669         */
 670        if (of_property_read_u32(np, "maxim,rsns-microohm", &prop) == 0) {
 671                pdata->r_sns = prop;
 672                pdata->enable_current_sense = true;
 673        }
 674
 675        return pdata;
 676}
 677#else
 678static struct max17042_platform_data *
 679max17042_get_pdata(struct device *dev)
 680{
 681        return dev->platform_data;
 682}
 683#endif
 684
 685static int max17042_probe(struct i2c_client *client,
 686                        const struct i2c_device_id *id)
 687{
 688        struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 689        struct max17042_chip *chip;
 690        int ret;
 691        int reg;
 692
 693        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
 694                return -EIO;
 695
 696        chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 697        if (!chip)
 698                return -ENOMEM;
 699
 700        chip->client = client;
 701        chip->pdata = max17042_get_pdata(&client->dev);
 702        if (!chip->pdata) {
 703                dev_err(&client->dev, "no platform data provided\n");
 704                return -EINVAL;
 705        }
 706
 707        i2c_set_clientdata(client, chip);
 708
 709        ret = max17042_read_reg(chip->client, MAX17042_DevName);
 710        if (ret == MAX17042_IC_VERSION) {
 711                dev_dbg(&client->dev, "chip type max17042 detected\n");
 712                chip->chip_type = MAX17042;
 713        } else if (ret == MAX17047_IC_VERSION) {
 714                dev_dbg(&client->dev, "chip type max17047/50 detected\n");
 715                chip->chip_type = MAX17047;
 716        } else {
 717                dev_err(&client->dev, "device version mismatch: %x\n", ret);
 718                return -EIO;
 719        }
 720
 721        chip->battery.name              = "max170xx_battery";
 722        chip->battery.type              = POWER_SUPPLY_TYPE_BATTERY;
 723        chip->battery.get_property      = max17042_get_property;
 724        chip->battery.properties        = max17042_battery_props;
 725        chip->battery.num_properties    = ARRAY_SIZE(max17042_battery_props);
 726
 727        /* When current is not measured,
 728         * CURRENT_NOW and CURRENT_AVG properties should be invisible. */
 729        if (!chip->pdata->enable_current_sense)
 730                chip->battery.num_properties -= 2;
 731
 732        if (chip->pdata->r_sns == 0)
 733                chip->pdata->r_sns = MAX17042_DEFAULT_SNS_RESISTOR;
 734
 735        if (chip->pdata->init_data)
 736                max17042_set_reg(client, chip->pdata->init_data,
 737                                chip->pdata->num_init_data);
 738
 739        if (!chip->pdata->enable_current_sense) {
 740                max17042_write_reg(client, MAX17042_CGAIN, 0x0000);
 741                max17042_write_reg(client, MAX17042_MiscCFG, 0x0003);
 742                max17042_write_reg(client, MAX17042_LearnCFG, 0x0007);
 743        }
 744
 745        ret = power_supply_register(&client->dev, &chip->battery);
 746        if (ret) {
 747                dev_err(&client->dev, "failed: power supply register\n");
 748                return ret;
 749        }
 750
 751        if (client->irq) {
 752                ret = request_threaded_irq(client->irq, NULL,
 753                                                max17042_thread_handler,
 754                                                IRQF_TRIGGER_FALLING,
 755                                                chip->battery.name, chip);
 756                if (!ret) {
 757                        reg =  max17042_read_reg(client, MAX17042_CONFIG);
 758                        reg |= CONFIG_ALRT_BIT_ENBL;
 759                        max17042_write_reg(client, MAX17042_CONFIG, reg);
 760                        max17042_set_soc_threshold(chip, 1);
 761                } else {
 762                        client->irq = 0;
 763                        dev_err(&client->dev, "%s(): cannot get IRQ\n",
 764                                __func__);
 765                }
 766        }
 767
 768        reg = max17042_read_reg(chip->client, MAX17042_STATUS);
 769        if (reg & STATUS_POR_BIT) {
 770                INIT_WORK(&chip->work, max17042_init_worker);
 771                schedule_work(&chip->work);
 772        } else {
 773                chip->init_complete = 1;
 774        }
 775
 776        return 0;
 777}
 778
 779static int max17042_remove(struct i2c_client *client)
 780{
 781        struct max17042_chip *chip = i2c_get_clientdata(client);
 782
 783        if (client->irq)
 784                free_irq(client->irq, chip);
 785        power_supply_unregister(&chip->battery);
 786        return 0;
 787}
 788
 789#ifdef CONFIG_PM
 790static int max17042_suspend(struct device *dev)
 791{
 792        struct max17042_chip *chip = dev_get_drvdata(dev);
 793
 794        /*
 795         * disable the irq and enable irq_wake
 796         * capability to the interrupt line.
 797         */
 798        if (chip->client->irq) {
 799                disable_irq(chip->client->irq);
 800                enable_irq_wake(chip->client->irq);
 801        }
 802
 803        return 0;
 804}
 805
 806static int max17042_resume(struct device *dev)
 807{
 808        struct max17042_chip *chip = dev_get_drvdata(dev);
 809
 810        if (chip->client->irq) {
 811                disable_irq_wake(chip->client->irq);
 812                enable_irq(chip->client->irq);
 813                /* re-program the SOC thresholds to 1% change */
 814                max17042_set_soc_threshold(chip, 1);
 815        }
 816
 817        return 0;
 818}
 819
 820static const struct dev_pm_ops max17042_pm_ops = {
 821        .suspend        = max17042_suspend,
 822        .resume         = max17042_resume,
 823};
 824
 825#define MAX17042_PM_OPS (&max17042_pm_ops)
 826#else
 827#define MAX17042_PM_OPS NULL
 828#endif
 829
 830#ifdef CONFIG_OF
 831static const struct of_device_id max17042_dt_match[] = {
 832        { .compatible = "maxim,max17042" },
 833        { .compatible = "maxim,max17047" },
 834        { .compatible = "maxim,max17050" },
 835        { },
 836};
 837MODULE_DEVICE_TABLE(of, max17042_dt_match);
 838#endif
 839
 840static const struct i2c_device_id max17042_id[] = {
 841        { "max17042", 0 },
 842        { "max17047", 1 },
 843        { "max17050", 2 },
 844        { }
 845};
 846MODULE_DEVICE_TABLE(i2c, max17042_id);
 847
 848static struct i2c_driver max17042_i2c_driver = {
 849        .driver = {
 850                .name   = "max17042",
 851                .of_match_table = of_match_ptr(max17042_dt_match),
 852                .pm     = MAX17042_PM_OPS,
 853        },
 854        .probe          = max17042_probe,
 855        .remove         = max17042_remove,
 856        .id_table       = max17042_id,
 857};
 858module_i2c_driver(max17042_i2c_driver);
 859
 860MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
 861MODULE_DESCRIPTION("MAX17042 Fuel Gauge");
 862MODULE_LICENSE("GPL");
 863
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