drivers/mfd/max14577.c

   1 /*
   2  * max14577.c - mfd core driver for the Maxim 14577/77836
   3  *
   4  * Copyright (C) 2014 Samsung Electronics
   5  * Chanwoo Choi <cw00.choi@samsung.com>
   6  * Krzysztof Kozlowski <k.kozlowski@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  * This driver is based on max8997.c
  19  */
  20
  21 #include <linux/err.h>
  22 #include <linux/module.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/of_device.h>
  25 #include <linux/mfd/core.h>
  26 #include <linux/mfd/max14577.h>
  27 #include <linux/mfd/max14577-private.h>
  28
  29 /*
  30  * Table of valid charger currents for different Maxim chipsets.
  31  * It is placed here because it is used by both charger and regulator driver.
  32  */
  33 const struct maxim_charger_current maxim_charger_currents[] = {
  34         [MAXIM_DEVICE_TYPE_UNKNOWN] = { 0, 0, 0, 0 },
  35         [MAXIM_DEVICE_TYPE_MAX14577] = {
  36                 .min            = MAX14577_CHARGER_CURRENT_LIMIT_MIN,
  37                 .high_start     = MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START,
  38                 .high_step      = MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP,
  39                 .max            = MAX14577_CHARGER_CURRENT_LIMIT_MAX,
  40         },
  41         [MAXIM_DEVICE_TYPE_MAX77836] = {
  42                 .min            = MAX77836_CHARGER_CURRENT_LIMIT_MIN,
  43                 .high_start     = MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START,
  44                 .high_step      = MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP,
  45                 .max            = MAX77836_CHARGER_CURRENT_LIMIT_MAX,
  46         },
  47 };
  48 EXPORT_SYMBOL_GPL(maxim_charger_currents);
  49
  50 /*
  51  * maxim_charger_calc_reg_current - Calculate register value for current
  52  * @limits:     constraints for charger, matching the MBCICHWRC register
  53  * @min_ua:     minimal requested current, micro Amps
  54  * @max_ua:     maximum requested current, micro Amps
  55  * @dst:        destination to store calculated register value
  56  *
  57  * Calculates the value of MBCICHWRC (Fast Battery Charge Current) register
  58  * for given current and stores it under pointed 'dst'. The stored value
  59  * combines low bit (MBCICHWRCL) and high bits (MBCICHWRCH). It is also
  60  * properly shifted.
  61  *
  62  * The calculated register value matches the current which:
  63  *  - is always between <limits.min, limits.max>;
  64  *  - is always less or equal to max_ua;
  65  *  - is the highest possible value;
  66  *  - may be lower than min_ua.
  67  *
  68  * On success returns 0. On error returns -EINVAL (requested min/max current
  69  * is outside of given charger limits) and 'dst' is not set.
  70  */
  71 int maxim_charger_calc_reg_current(const struct maxim_charger_current *limits,
  72                 unsigned int min_ua, unsigned int max_ua, u8 *dst)
  73 {
  74         unsigned int current_bits = 0xf;
  75
  76         if (min_ua > max_ua)
  77                 return -EINVAL;
  78
  79         if (min_ua > limits->max || max_ua < limits->min)
  80                 return -EINVAL;
  81
  82         if (max_ua < limits->high_start) {
  83                 /*
  84                  * Less than high_start, so set the minimal current
  85                  * (turn Low Bit off, 0 as high bits).
  86                  */
  87                 *dst = 0x0;
  88                 return 0;
  89         }
  90
  91         /* max_ua is in range: <high_start, infinite>, cut it to limits.max */
  92         max_ua = min(limits->max, max_ua);
  93         max_ua -= limits->high_start;
  94         /*
  95          * There is no risk of overflow 'max_ua' here because:
  96          *  - max_ua >= limits.high_start
  97          *  - BUILD_BUG checks that 'limits' are: max >= high_start + high_step
  98          */
  99         current_bits = max_ua / limits->high_step;
 100
 101         /* Turn Low Bit on (use range <limits.high_start, limits.max>) ... */
 102         *dst = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
 103         /* and set proper High Bits */
 104         *dst |= current_bits << CHGCTRL4_MBCICHWRCH_SHIFT;
 105
 106         return 0;
 107 }
 108 EXPORT_SYMBOL_GPL(maxim_charger_calc_reg_current);
 109
 110 static const struct mfd_cell max14577_devs[] = {
 111         {
 112                 .name = "max14577-muic",
 113                 .of_compatible = "maxim,max14577-muic",
 114         },
 115         {
 116                 .name = "max14577-regulator",
 117                 .of_compatible = "maxim,max14577-regulator",
 118         },
 119         {
 120                 .name = "max14577-charger",
 121                 .of_compatible = "maxim,max14577-charger",
 122         },
 123 };
 124
 125 static const struct mfd_cell max77836_devs[] = {
 126         {
 127                 .name = "max77836-muic",
 128                 .of_compatible = "maxim,max77836-muic",
 129         },
 130         {
 131                 .name = "max77836-regulator",
 132                 .of_compatible = "maxim,max77836-regulator",
 133         },
 134         {
 135                 .name = "max77836-charger",
 136                 .of_compatible = "maxim,max77836-charger",
 137         },
 138         {
 139                 .name = "max77836-battery",
 140                 .of_compatible = "maxim,max77836-battery",
 141         },
 142 };
 143
 144 static const struct of_device_id max14577_dt_match[] = {
 145         {
 146                 .compatible = "maxim,max14577",
 147                 .data = (void *)MAXIM_DEVICE_TYPE_MAX14577,
 148         },
 149         {
 150                 .compatible = "maxim,max77836",
 151                 .data = (void *)MAXIM_DEVICE_TYPE_MAX77836,
 152         },
 153         {},
 154 };
 155
 156 static bool max14577_muic_volatile_reg(struct device *dev, unsigned int reg)
 157 {
 158         switch (reg) {
 159         case MAX14577_REG_INT1 ... MAX14577_REG_STATUS3:
 160                 return true;
 161         default:
 162                 break;
 163         }
 164         return false;
 165 }
 166
 167 static bool max77836_muic_volatile_reg(struct device *dev, unsigned int reg)
 168 {
 169         /* Any max14577 volatile registers are also max77836 volatile. */
 170         if (max14577_muic_volatile_reg(dev, reg))
 171                 return true;
 172
 173         switch (reg) {
 174         case MAX77836_FG_REG_VCELL_MSB ... MAX77836_FG_REG_SOC_LSB:
 175         case MAX77836_FG_REG_CRATE_MSB ... MAX77836_FG_REG_CRATE_LSB:
 176         case MAX77836_FG_REG_STATUS_H ... MAX77836_FG_REG_STATUS_L:
 177         case MAX77836_PMIC_REG_INTSRC:
 178         case MAX77836_PMIC_REG_TOPSYS_INT:
 179         case MAX77836_PMIC_REG_TOPSYS_STAT:
 180                 return true;
 181         default:
 182                 break;
 183         }
 184         return false;
 185 }
 186
 187 static const struct regmap_config max14577_muic_regmap_config = {
 188         .reg_bits       = 8,
 189         .val_bits       = 8,
 190         .volatile_reg   = max14577_muic_volatile_reg,
 191         .max_register   = MAX14577_REG_END,
 192 };
 193
 194 static const struct regmap_config max77836_pmic_regmap_config = {
 195         .reg_bits       = 8,
 196         .val_bits       = 8,
 197         .volatile_reg   = max77836_muic_volatile_reg,
 198         .max_register   = MAX77836_PMIC_REG_END,
 199 };
 200
 201 static const struct regmap_irq max14577_irqs[] = {
 202         /* INT1 interrupts */
 203         { .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
 204         { .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
 205         { .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
 206         /* INT2 interrupts */
 207         { .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
 208         { .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
 209         { .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
 210         { .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
 211         { .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
 212         /* INT3 interrupts */
 213         { .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
 214         { .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
 215         { .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
 216         { .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
 217 };
 218
 219 static const struct regmap_irq_chip max14577_irq_chip = {
 220         .name                   = "max14577",
 221         .status_base            = MAX14577_REG_INT1,
 222         .mask_base              = MAX14577_REG_INTMASK1,
 223         .mask_invert            = true,
 224         .num_regs               = 3,
 225         .irqs                   = max14577_irqs,
 226         .num_irqs               = ARRAY_SIZE(max14577_irqs),
 227 };
 228
 229 static const struct regmap_irq max77836_muic_irqs[] = {
 230         /* INT1 interrupts */
 231         { .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
 232         { .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
 233         { .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
 234         { .reg_offset = 0, .mask = MAX77836_INT1_ADC1K_MASK, },
 235         /* INT2 interrupts */
 236         { .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
 237         { .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
 238         { .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
 239         { .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
 240         { .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
 241         { .reg_offset = 1, .mask = MAX77836_INT2_VIDRM_MASK, },
 242         /* INT3 interrupts */
 243         { .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
 244         { .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
 245         { .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
 246         { .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
 247 };
 248
 249 static const struct regmap_irq_chip max77836_muic_irq_chip = {
 250         .name                   = "max77836-muic",
 251         .status_base            = MAX14577_REG_INT1,
 252         .mask_base              = MAX14577_REG_INTMASK1,
 253         .mask_invert            = true,
 254         .num_regs               = 3,
 255         .irqs                   = max77836_muic_irqs,
 256         .num_irqs               = ARRAY_SIZE(max77836_muic_irqs),
 257 };
 258
 259 static const struct regmap_irq max77836_pmic_irqs[] = {
 260         { .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T120C_MASK, },
 261         { .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T140C_MASK, },
 262 };
 263
 264 static const struct regmap_irq_chip max77836_pmic_irq_chip = {
 265         .name                   = "max77836-pmic",
 266         .status_base            = MAX77836_PMIC_REG_TOPSYS_INT,
 267         .mask_base              = MAX77836_PMIC_REG_TOPSYS_INT_MASK,
 268         .mask_invert            = false,
 269         .num_regs               = 1,
 270         .irqs                   = max77836_pmic_irqs,
 271         .num_irqs               = ARRAY_SIZE(max77836_pmic_irqs),
 272 };
 273
 274 static void max14577_print_dev_type(struct max14577 *max14577)
 275 {
 276         u8 reg_data, vendor_id, device_id;
 277         int ret;
 278
 279         ret = max14577_read_reg(max14577->regmap, MAX14577_REG_DEVICEID,
 280                         &reg_data);
 281         if (ret) {
 282                 dev_err(max14577->dev,
 283                         "Failed to read DEVICEID register: %d\n", ret);
 284                 return;
 285         }
 286
 287         vendor_id = ((reg_data & DEVID_VENDORID_MASK) >>
 288                                 DEVID_VENDORID_SHIFT);
 289         device_id = ((reg_data & DEVID_DEVICEID_MASK) >>
 290                                 DEVID_DEVICEID_SHIFT);
 291
 292         dev_info(max14577->dev, "Device type: %u (ID: 0x%x, vendor: 0x%x)\n",
 293                         max14577->dev_type, device_id, vendor_id);
 294 }
 295
 296 /*
 297  * Max77836 specific initialization code for driver probe.
 298  * Adds new I2C dummy device, regmap and regmap IRQ chip.
 299  * Unmasks Interrupt Source register.
 300  *
 301  * On success returns 0.
 302  * On failure returns errno and reverts any changes done so far (e.g. remove
 303  * I2C dummy device), except masking the INT SRC register.
 304  */
 305 static int max77836_init(struct max14577 *max14577)
 306 {
 307         int ret;
 308         u8 intsrc_mask;
 309
 310         max14577->i2c_pmic = i2c_new_dummy(max14577->i2c->adapter,
 311                         I2C_ADDR_PMIC);
 312         if (!max14577->i2c_pmic) {
 313                 dev_err(max14577->dev, "Failed to register PMIC I2C device\n");
 314                 return -ENODEV;
 315         }
 316         i2c_set_clientdata(max14577->i2c_pmic, max14577);
 317
 318         max14577->regmap_pmic = devm_regmap_init_i2c(max14577->i2c_pmic,
 319                         &max77836_pmic_regmap_config);
 320         if (IS_ERR(max14577->regmap_pmic)) {
 321                 ret = PTR_ERR(max14577->regmap_pmic);
 322                 dev_err(max14577->dev, "Failed to allocate PMIC register map: %d\n",
 323                                 ret);
 324                 goto err;
 325         }
 326
 327         /* Un-mask MAX77836 Interrupt Source register */
 328         ret = max14577_read_reg(max14577->regmap_pmic,
 329                         MAX77836_PMIC_REG_INTSRC_MASK, &intsrc_mask);
 330         if (ret < 0) {
 331                 dev_err(max14577->dev, "Failed to read PMIC register\n");
 332                 goto err;
 333         }
 334
 335         intsrc_mask &= ~(MAX77836_INTSRC_MASK_TOP_INT_MASK);
 336         intsrc_mask &= ~(MAX77836_INTSRC_MASK_MUIC_CHG_INT_MASK);
 337         ret = max14577_write_reg(max14577->regmap_pmic,
 338                         MAX77836_PMIC_REG_INTSRC_MASK, intsrc_mask);
 339         if (ret < 0) {
 340                 dev_err(max14577->dev, "Failed to write PMIC register\n");
 341                 goto err;
 342         }
 343
 344         ret = regmap_add_irq_chip(max14577->regmap_pmic, max14577->irq,
 345                         IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED,
 346                         0, &max77836_pmic_irq_chip,
 347                         &max14577->irq_data_pmic);
 348         if (ret != 0) {
 349                 dev_err(max14577->dev, "Failed to request PMIC IRQ %d: %d\n",
 350                                 max14577->irq, ret);
 351                 goto err;
 352         }
 353
 354         return 0;
 355
 356 err:
 357         i2c_unregister_device(max14577->i2c_pmic);
 358
 359         return ret;
 360 }
 361
 362 /*
 363  * Max77836 specific de-initialization code for driver remove.
 364  */
 365 static void max77836_remove(struct max14577 *max14577)
 366 {
 367         regmap_del_irq_chip(max14577->irq, max14577->irq_data_pmic);
 368         i2c_unregister_device(max14577->i2c_pmic);
 369 }
 370
 371 static int max14577_i2c_probe(struct i2c_client *i2c,
 372                               const struct i2c_device_id *id)
 373 {
 374         struct max14577 *max14577;
 375         struct max14577_platform_data *pdata = dev_get_platdata(&i2c->dev);
 376         struct device_node *np = i2c->dev.of_node;
 377         int ret = 0;
 378         const struct regmap_irq_chip *irq_chip;
 379         const struct mfd_cell *mfd_devs;
 380         unsigned int mfd_devs_size;
 381         int irq_flags;
 382
 383         if (np) {
 384                 pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
 385                 if (!pdata)
 386                         return -ENOMEM;
 387                 i2c->dev.platform_data = pdata;
 388         }
 389
 390         if (!pdata) {
 391                 dev_err(&i2c->dev, "No platform data found.\n");
 392                 return -EINVAL;
 393         }
 394
 395         max14577 = devm_kzalloc(&i2c->dev, sizeof(*max14577), GFP_KERNEL);
 396         if (!max14577)
 397                 return -ENOMEM;
 398
 399         i2c_set_clientdata(i2c, max14577);
 400         max14577->dev = &i2c->dev;
 401         max14577->i2c = i2c;
 402         max14577->irq = i2c->irq;
 403
 404         max14577->regmap = devm_regmap_init_i2c(i2c,
 405                         &max14577_muic_regmap_config);
 406         if (IS_ERR(max14577->regmap)) {
 407                 ret = PTR_ERR(max14577->regmap);
 408                 dev_err(max14577->dev, "Failed to allocate register map: %d\n",
 409                                 ret);
 410                 return ret;
 411         }
 412
 413         if (np) {
 414                 const struct of_device_id *of_id;
 415
 416                 of_id = of_match_device(max14577_dt_match, &i2c->dev);
 417                 if (of_id)
 418                         max14577->dev_type =
 419                                 (enum maxim_device_type)of_id->data;
 420         } else {
 421                 max14577->dev_type = id->driver_data;
 422         }
 423
 424         max14577_print_dev_type(max14577);
 425
 426         switch (max14577->dev_type) {
 427         case MAXIM_DEVICE_TYPE_MAX77836:
 428                 irq_chip = &max77836_muic_irq_chip;
 429                 mfd_devs = max77836_devs;
 430                 mfd_devs_size = ARRAY_SIZE(max77836_devs);
 431                 irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED;
 432                 break;
 433         case MAXIM_DEVICE_TYPE_MAX14577:
 434         default:
 435                 irq_chip = &max14577_irq_chip;
 436                 mfd_devs = max14577_devs;
 437                 mfd_devs_size = ARRAY_SIZE(max14577_devs);
 438                 irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;
 439                 break;
 440         }
 441
 442         ret = regmap_add_irq_chip(max14577->regmap, max14577->irq,
 443                                   irq_flags, 0, irq_chip,
 444                                   &max14577->irq_data);
 445         if (ret != 0) {
 446                 dev_err(&i2c->dev, "Failed to request IRQ %d: %d\n",
 447                                 max14577->irq, ret);
 448                 return ret;
 449         }
 450
 451         /* Max77836 specific initialization code (additional regmap) */
 452         if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836) {
 453                 ret = max77836_init(max14577);
 454                 if (ret < 0)
 455                         goto err_max77836;
 456         }
 457
 458         ret = mfd_add_devices(max14577->dev, -1, mfd_devs,
 459                         mfd_devs_size, NULL, 0, NULL);
 460         if (ret < 0)
 461                 goto err_mfd;
 462
 463         device_init_wakeup(max14577->dev, 1);
 464
 465         return 0;
 466
 467 err_mfd:
 468         if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
 469                 max77836_remove(max14577);
 470 err_max77836:
 471         regmap_del_irq_chip(max14577->irq, max14577->irq_data);
 472
 473         return ret;
 474 }
 475
 476 static int max14577_i2c_remove(struct i2c_client *i2c)
 477 {
 478         struct max14577 *max14577 = i2c_get_clientdata(i2c);
 479
 480         mfd_remove_devices(max14577->dev);
 481         regmap_del_irq_chip(max14577->irq, max14577->irq_data);
 482         if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
 483                 max77836_remove(max14577);
 484
 485         return 0;
 486 }
 487
 488 static const struct i2c_device_id max14577_i2c_id[] = {
 489         { "max14577", MAXIM_DEVICE_TYPE_MAX14577, },
 490         { "max77836", MAXIM_DEVICE_TYPE_MAX77836, },
 491         { }
 492 };
 493 MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
 494
 495 #ifdef CONFIG_PM_SLEEP
 496 static int max14577_suspend(struct device *dev)
 497 {
 498         struct i2c_client *i2c = to_i2c_client(dev);
 499         struct max14577 *max14577 = i2c_get_clientdata(i2c);
 500
 501         if (device_may_wakeup(dev))
 502                 enable_irq_wake(max14577->irq);
 503         /*
 504          * MUIC IRQ must be disabled during suspend because if it happens
 505          * while suspended it will be handled before resuming I2C.
 506          *
 507          * When device is woken up from suspend (e.g. by ADC change),
 508          * an interrupt occurs before resuming I2C bus controller.
 509          * Interrupt handler tries to read registers but this read
 510          * will fail because I2C is still suspended.
 511          */
 512         disable_irq(max14577->irq);
 513
 514         return 0;
 515 }
 516
 517 static int max14577_resume(struct device *dev)
 518 {
 519         struct i2c_client *i2c = to_i2c_client(dev);
 520         struct max14577 *max14577 = i2c_get_clientdata(i2c);
 521
 522         if (device_may_wakeup(dev))
 523                 disable_irq_wake(max14577->irq);
 524         enable_irq(max14577->irq);
 525
 526         return 0;
 527 }
 528 #endif /* CONFIG_PM_SLEEP */
 529
 530 static SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
 531
 532 static struct i2c_driver max14577_i2c_driver = {
 533         .driver = {
 534                 .name = "max14577",
 535                 .pm = &max14577_pm,
 536                 .of_match_table = max14577_dt_match,
 537         },
 538         .probe = max14577_i2c_probe,
 539         .remove = max14577_i2c_remove,
 540         .id_table = max14577_i2c_id,
 541 };
 542
 543 static int __init max14577_i2c_init(void)
 544 {
 545         BUILD_BUG_ON(ARRAY_SIZE(max14577_i2c_id) != MAXIM_DEVICE_TYPE_NUM);
 546         BUILD_BUG_ON(ARRAY_SIZE(max14577_dt_match) != MAXIM_DEVICE_TYPE_NUM);
 547
 548         /* Valid charger current values must be provided for each chipset */
 549         BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
 550
 551         /* Check for valid values for charger */
 552         BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START +
 553                         MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
 554                         MAX14577_CHARGER_CURRENT_LIMIT_MAX);
 555         BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
 556
 557         BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START +
 558                         MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
 559                         MAX77836_CHARGER_CURRENT_LIMIT_MAX);
 560         BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
 561
 562         return i2c_add_driver(&max14577_i2c_driver);
 563 }
 564 subsys_initcall(max14577_i2c_init);
 565
 566 static void __exit max14577_i2c_exit(void)
 567 {
 568         i2c_del_driver(&max14577_i2c_driver);
 569 }
 570 module_exit(max14577_i2c_exit);
 571
 572 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <k.kozlowski@samsung.com>");
 573 MODULE_DESCRIPTION("Maxim 14577/77836 multi-function core driver");
 574 MODULE_LICENSE("GPL");