drivers/regulator/max77686.c

   1 /*
   2  * max77686.c - Regulator driver for the Maxim 77686
   3  *
   4  * Copyright (C) 2012 Samsung Electronics
   5  * Chiwoong Byun <woong.byun@smasung.com>
   6  * Jonghwa Lee <jonghwa3.lee@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 max8997.c
  23  */
  24
  25 #include <linux/kernel.h>
  26 #include <linux/bug.h>
  27 #include <linux/delay.h>
  28 #include <linux/err.h>
  29 #include <linux/gpio.h>
  30 #include <linux/slab.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/regulator/driver.h>
  33 #include <linux/regulator/machine.h>
  34 #include <linux/regulator/of_regulator.h>
  35 #include <linux/mfd/max77686.h>
  36 #include <linux/mfd/max77686-private.h>
  37
  38 #define MAX77686_LDO_MINUV      800000
  39 #define MAX77686_LDO_UVSTEP     50000
  40 #define MAX77686_LDO_LOW_MINUV  800000
  41 #define MAX77686_LDO_LOW_UVSTEP 25000
  42 #define MAX77686_BUCK_MINUV     750000
  43 #define MAX77686_BUCK_UVSTEP    50000
  44 #define MAX77686_RAMP_DELAY     100000                  /* uV/us */
  45 #define MAX77686_DVS_RAMP_DELAY 27500                   /* uV/us */
  46 #define MAX77686_DVS_MINUV      600000
  47 #define MAX77686_DVS_UVSTEP     12500
  48
  49 #define MAX77686_OPMODE_SHIFT   6
  50 #define MAX77686_OPMODE_BUCK234_SHIFT   4
  51 #define MAX77686_OPMODE_MASK    0x3
  52
  53 #define MAX77686_VSEL_MASK      0x3F
  54 #define MAX77686_DVS_VSEL_MASK  0xFF
  55
  56 #define MAX77686_RAMP_RATE_MASK 0xC0
  57
  58 #define MAX77686_REGULATORS     MAX77686_REG_MAX
  59 #define MAX77686_LDOS           26
  60
  61 enum max77686_ramp_rate {
  62         RAMP_RATE_13P75MV,
  63         RAMP_RATE_27P5MV,
  64         RAMP_RATE_55MV,
  65         RAMP_RATE_NO_CTRL,      /* 100mV/us */
  66 };
  67
  68 struct max77686_data {
  69         struct regulator_dev *rdev[MAX77686_REGULATORS];
  70         unsigned int opmode[MAX77686_REGULATORS];
  71 };
  72
  73 /* Some BUCKS supports Normal[ON/OFF] mode during suspend */
  74 static int max77686_buck_set_suspend_disable(struct regulator_dev *rdev)
  75 {
  76         unsigned int val;
  77         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  78         int id = rdev_get_id(rdev);
  79
  80         if (id == MAX77686_BUCK1)
  81                 val = 0x1;
  82         else
  83                 val = 0x1 << MAX77686_OPMODE_BUCK234_SHIFT;
  84
  85         max77686->opmode[id] = val;
  86         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  87                                   rdev->desc->enable_mask,
  88                                   val);
  89 }
  90
  91 /* Some LDOs supports [LPM/Normal]ON mode during suspend state */
  92 static int max77686_set_suspend_mode(struct regulator_dev *rdev,
  93                                      unsigned int mode)
  94 {
  95         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
  96         unsigned int val;
  97         int id = rdev_get_id(rdev);
  98
  99         /* BUCK[5-9] doesn't support this feature */
 100         if (id >= MAX77686_BUCK5)
 101                 return 0;
 102
 103         switch (mode) {
 104         case REGULATOR_MODE_IDLE:                       /* ON in LP Mode */
 105                 val = 0x2 << MAX77686_OPMODE_SHIFT;
 106                 break;
 107         case REGULATOR_MODE_NORMAL:                     /* ON in Normal Mode */
 108                 val = 0x3 << MAX77686_OPMODE_SHIFT;
 109                 break;
 110         default:
 111                 pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
 112                         rdev->desc->name, mode);
 113                 return -EINVAL;
 114         }
 115
 116         max77686->opmode[id] = val;
 117         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 118                                   rdev->desc->enable_mask,
 119                                   val);
 120 }
 121
 122 /* Some LDOs supports LPM-ON/OFF/Normal-ON mode during suspend state */
 123 static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
 124                                      unsigned int mode)
 125 {
 126         unsigned int val;
 127         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
 128
 129         switch (mode) {
 130         case REGULATOR_MODE_STANDBY:                    /* switch off */
 131                 val = 0x1 << MAX77686_OPMODE_SHIFT;
 132                 break;
 133         case REGULATOR_MODE_IDLE:                       /* ON in LP Mode */
 134                 val = 0x2 << MAX77686_OPMODE_SHIFT;
 135                 break;
 136         case REGULATOR_MODE_NORMAL:                     /* ON in Normal Mode */
 137                 val = 0x3 << MAX77686_OPMODE_SHIFT;
 138                 break;
 139         default:
 140                 pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
 141                         rdev->desc->name, mode);
 142                 return -EINVAL;
 143         }
 144
 145         max77686->opmode[rdev_get_id(rdev)] = val;
 146         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 147                                   rdev->desc->enable_mask,
 148                                   val);
 149 }
 150
 151 static int max77686_enable(struct regulator_dev *rdev)
 152 {
 153         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
 154
 155         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 156                                   rdev->desc->enable_mask,
 157                                   max77686->opmode[rdev_get_id(rdev)]);
 158 }
 159
 160 static int max77686_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
 161 {
 162         unsigned int ramp_value = RAMP_RATE_NO_CTRL;
 163
 164         switch (ramp_delay) {
 165         case 1 ... 13750:
 166                 ramp_value = RAMP_RATE_13P75MV;
 167                 break;
 168         case 13751 ... 27500:
 169                 ramp_value = RAMP_RATE_27P5MV;
 170                 break;
 171         case 27501 ... 55000:
 172                 ramp_value = RAMP_RATE_55MV;
 173                 break;
 174         case 55001 ... 100000:
 175                 break;
 176         default:
 177                 pr_warn("%s: ramp_delay: %d not supported, setting 100000\n",
 178                         rdev->desc->name, ramp_delay);
 179         }
 180
 181         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
 182                                   MAX77686_RAMP_RATE_MASK, ramp_value << 6);
 183 }
 184
 185 static struct regulator_ops max77686_ops = {
 186         .list_voltage           = regulator_list_voltage_linear,
 187         .map_voltage            = regulator_map_voltage_linear,
 188         .is_enabled             = regulator_is_enabled_regmap,
 189         .enable                 = max77686_enable,
 190         .disable                = regulator_disable_regmap,
 191         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 192         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 193         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 194         .set_suspend_mode       = max77686_set_suspend_mode,
 195 };
 196
 197 static struct regulator_ops max77686_ldo_ops = {
 198         .list_voltage           = regulator_list_voltage_linear,
 199         .map_voltage            = regulator_map_voltage_linear,
 200         .is_enabled             = regulator_is_enabled_regmap,
 201         .enable                 = max77686_enable,
 202         .disable                = regulator_disable_regmap,
 203         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 204         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 205         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 206         .set_suspend_mode       = max77686_ldo_set_suspend_mode,
 207 };
 208
 209 static struct regulator_ops max77686_buck1_ops = {
 210         .list_voltage           = regulator_list_voltage_linear,
 211         .map_voltage            = regulator_map_voltage_linear,
 212         .is_enabled             = regulator_is_enabled_regmap,
 213         .enable                 = max77686_enable,
 214         .disable                = regulator_disable_regmap,
 215         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 216         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 217         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 218         .set_suspend_disable    = max77686_buck_set_suspend_disable,
 219 };
 220
 221 static struct regulator_ops max77686_buck_dvs_ops = {
 222         .list_voltage           = regulator_list_voltage_linear,
 223         .map_voltage            = regulator_map_voltage_linear,
 224         .is_enabled             = regulator_is_enabled_regmap,
 225         .enable                 = max77686_enable,
 226         .disable                = regulator_disable_regmap,
 227         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
 228         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
 229         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
 230         .set_ramp_delay         = max77686_set_ramp_delay,
 231         .set_suspend_disable    = max77686_buck_set_suspend_disable,
 232 };
 233
 234 #define regulator_desc_ldo(num)         {                               \
 235         .name           = "LDO"#num,                                    \
 236         .id             = MAX77686_LDO##num,                            \
 237         .ops            = &max77686_ops,                                \
 238         .type           = REGULATOR_VOLTAGE,                            \
 239         .owner          = THIS_MODULE,                                  \
 240         .min_uV         = MAX77686_LDO_MINUV,                           \
 241         .uV_step        = MAX77686_LDO_UVSTEP,                          \
 242         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 243         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 244         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 245         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 246         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 247         .enable_mask    = MAX77686_OPMODE_MASK                          \
 248                         << MAX77686_OPMODE_SHIFT,                       \
 249 }
 250 #define regulator_desc_lpm_ldo(num)     {                               \
 251         .name           = "LDO"#num,                                    \
 252         .id             = MAX77686_LDO##num,                            \
 253         .ops            = &max77686_ldo_ops,                            \
 254         .type           = REGULATOR_VOLTAGE,                            \
 255         .owner          = THIS_MODULE,                                  \
 256         .min_uV         = MAX77686_LDO_MINUV,                           \
 257         .uV_step        = MAX77686_LDO_UVSTEP,                          \
 258         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 259         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 260         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 261         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 262         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 263         .enable_mask    = MAX77686_OPMODE_MASK                          \
 264                         << MAX77686_OPMODE_SHIFT,                       \
 265 }
 266 #define regulator_desc_ldo_low(num)             {                       \
 267         .name           = "LDO"#num,                                    \
 268         .id             = MAX77686_LDO##num,                            \
 269         .ops            = &max77686_ldo_ops,                            \
 270         .type           = REGULATOR_VOLTAGE,                            \
 271         .owner          = THIS_MODULE,                                  \
 272         .min_uV         = MAX77686_LDO_LOW_MINUV,                       \
 273         .uV_step        = MAX77686_LDO_LOW_UVSTEP,                      \
 274         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 275         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 276         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 277         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 278         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 279         .enable_mask    = MAX77686_OPMODE_MASK                          \
 280                         << MAX77686_OPMODE_SHIFT,                       \
 281 }
 282 #define regulator_desc_ldo1_low(num)            {                       \
 283         .name           = "LDO"#num,                                    \
 284         .id             = MAX77686_LDO##num,                            \
 285         .ops            = &max77686_ops,                                \
 286         .type           = REGULATOR_VOLTAGE,                            \
 287         .owner          = THIS_MODULE,                                  \
 288         .min_uV         = MAX77686_LDO_LOW_MINUV,                       \
 289         .uV_step        = MAX77686_LDO_LOW_UVSTEP,                      \
 290         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 291         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 292         .vsel_reg       = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 293         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 294         .enable_reg     = MAX77686_REG_LDO1CTRL1 + num - 1,             \
 295         .enable_mask    = MAX77686_OPMODE_MASK                          \
 296                         << MAX77686_OPMODE_SHIFT,                       \
 297 }
 298 #define regulator_desc_buck(num)                {                       \
 299         .name           = "BUCK"#num,                                   \
 300         .id             = MAX77686_BUCK##num,                           \
 301         .ops            = &max77686_ops,                                \
 302         .type           = REGULATOR_VOLTAGE,                            \
 303         .owner          = THIS_MODULE,                                  \
 304         .min_uV         = MAX77686_BUCK_MINUV,                          \
 305         .uV_step        = MAX77686_BUCK_UVSTEP,                         \
 306         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 307         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 308         .vsel_reg       = MAX77686_REG_BUCK5OUT + (num - 5) * 2,        \
 309         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 310         .enable_reg     = MAX77686_REG_BUCK5CTRL + (num - 5) * 2,       \
 311         .enable_mask    = MAX77686_OPMODE_MASK,                         \
 312 }
 313 #define regulator_desc_buck1(num)               {                       \
 314         .name           = "BUCK"#num,                                   \
 315         .id             = MAX77686_BUCK##num,                           \
 316         .ops            = &max77686_buck1_ops,                          \
 317         .type           = REGULATOR_VOLTAGE,                            \
 318         .owner          = THIS_MODULE,                                  \
 319         .min_uV         = MAX77686_BUCK_MINUV,                          \
 320         .uV_step        = MAX77686_BUCK_UVSTEP,                         \
 321         .ramp_delay     = MAX77686_RAMP_DELAY,                          \
 322         .n_voltages     = MAX77686_VSEL_MASK + 1,                       \
 323         .vsel_reg       = MAX77686_REG_BUCK1OUT,                        \
 324         .vsel_mask      = MAX77686_VSEL_MASK,                           \
 325         .enable_reg     = MAX77686_REG_BUCK1CTRL,                       \
 326         .enable_mask    = MAX77686_OPMODE_MASK,                         \
 327 }
 328 #define regulator_desc_buck_dvs(num)            {                       \
 329         .name           = "BUCK"#num,                                   \
 330         .id             = MAX77686_BUCK##num,                           \
 331         .ops            = &max77686_buck_dvs_ops,                       \
 332         .type           = REGULATOR_VOLTAGE,                            \
 333         .owner          = THIS_MODULE,                                  \
 334         .min_uV         = MAX77686_DVS_MINUV,                           \
 335         .uV_step        = MAX77686_DVS_UVSTEP,                          \
 336         .ramp_delay     = MAX77686_DVS_RAMP_DELAY,                      \
 337         .n_voltages     = MAX77686_DVS_VSEL_MASK + 1,                   \
 338         .vsel_reg       = MAX77686_REG_BUCK2DVS1 + (num - 2) * 10,      \
 339         .vsel_mask      = MAX77686_DVS_VSEL_MASK,                       \
 340         .enable_reg     = MAX77686_REG_BUCK2CTRL1 + (num - 2) * 10,     \
 341         .enable_mask    = MAX77686_OPMODE_MASK                          \
 342                         << MAX77686_OPMODE_BUCK234_SHIFT,               \
 343 }
 344
 345 static struct regulator_desc regulators[] = {
 346         regulator_desc_ldo1_low(1),
 347         regulator_desc_ldo_low(2),
 348         regulator_desc_ldo(3),
 349         regulator_desc_ldo(4),
 350         regulator_desc_ldo(5),
 351         regulator_desc_ldo_low(6),
 352         regulator_desc_ldo_low(7),
 353         regulator_desc_ldo_low(8),
 354         regulator_desc_ldo(9),
 355         regulator_desc_lpm_ldo(10),
 356         regulator_desc_lpm_ldo(11),
 357         regulator_desc_lpm_ldo(12),
 358         regulator_desc_ldo(13),
 359         regulator_desc_lpm_ldo(14),
 360         regulator_desc_ldo_low(15),
 361         regulator_desc_lpm_ldo(16),
 362         regulator_desc_ldo(17),
 363         regulator_desc_ldo(18),
 364         regulator_desc_ldo(19),
 365         regulator_desc_ldo(20),
 366         regulator_desc_ldo(21),
 367         regulator_desc_ldo(22),
 368         regulator_desc_ldo(23),
 369         regulator_desc_ldo(24),
 370         regulator_desc_ldo(25),
 371         regulator_desc_ldo(26),
 372         regulator_desc_buck1(1),
 373         regulator_desc_buck_dvs(2),
 374         regulator_desc_buck_dvs(3),
 375         regulator_desc_buck_dvs(4),
 376         regulator_desc_buck(5),
 377         regulator_desc_buck(6),
 378         regulator_desc_buck(7),
 379         regulator_desc_buck(8),
 380         regulator_desc_buck(9),
 381 };
 382
 383 #ifdef CONFIG_OF
 384 static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
 385                                         struct max77686_platform_data *pdata)
 386 {
 387         struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 388         struct device_node *pmic_np, *regulators_np;
 389         struct max77686_regulator_data *rdata;
 390         struct of_regulator_match rmatch;
 391         unsigned int i;
 392
 393         pmic_np = iodev->dev->of_node;
 394         regulators_np = of_find_node_by_name(pmic_np, "voltage-regulators");
 395         if (!regulators_np) {
 396                 dev_err(&pdev->dev, "could not find regulators sub-node\n");
 397                 return -EINVAL;
 398         }
 399
 400         pdata->num_regulators = ARRAY_SIZE(regulators);
 401         rdata = devm_kzalloc(&pdev->dev, sizeof(*rdata) *
 402                              pdata->num_regulators, GFP_KERNEL);
 403         if (!rdata) {
 404                 dev_err(&pdev->dev,
 405                         "could not allocate memory for regulator data\n");
 406                 return -ENOMEM;
 407         }
 408
 409         for (i = 0; i < pdata->num_regulators; i++) {
 410                 rmatch.name = regulators[i].name;
 411                 rmatch.init_data = NULL;
 412                 rmatch.of_node = NULL;
 413                 of_regulator_match(&pdev->dev, regulators_np, &rmatch, 1);
 414                 rdata[i].initdata = rmatch.init_data;
 415                 rdata[i].of_node = rmatch.of_node;
 416         }
 417
 418         pdata->regulators = rdata;
 419
 420         return 0;
 421 }
 422 #else
 423 static int max77686_pmic_dt_parse_pdata(struct platform_device *pdev,
 424                                         struct max77686_platform_data *pdata)
 425 {
 426         return 0;
 427 }
 428 #endif /* CONFIG_OF */
 429
 430 static int max77686_pmic_probe(struct platform_device *pdev)
 431 {
 432         struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 433         struct max77686_platform_data *pdata = dev_get_platdata(iodev->dev);
 434         struct max77686_data *max77686;
 435         int i, ret = 0;
 436         struct regulator_config config = { };
 437
 438         dev_dbg(&pdev->dev, "%s\n", __func__);
 439
 440         if (!pdata) {
 441                 dev_err(&pdev->dev, "no platform data found for regulator\n");
 442                 return -ENODEV;
 443         }
 444
 445         if (iodev->dev->of_node) {
 446                 ret = max77686_pmic_dt_parse_pdata(pdev, pdata);
 447                 if (ret)
 448                         return ret;
 449         }
 450
 451         if (pdata->num_regulators != MAX77686_REGULATORS) {
 452                 dev_err(&pdev->dev,
 453                         "Invalid initial data for regulator's initialiation\n");
 454                 return -EINVAL;
 455         }
 456
 457         max77686 = devm_kzalloc(&pdev->dev, sizeof(struct max77686_data),
 458                                 GFP_KERNEL);
 459         if (!max77686)
 460                 return -ENOMEM;
 461
 462         config.dev = &pdev->dev;
 463         config.regmap = iodev->regmap;
 464         config.driver_data = max77686;
 465         platform_set_drvdata(pdev, max77686);
 466
 467         for (i = 0; i < MAX77686_REGULATORS; i++) {
 468                 config.init_data = pdata->regulators[i].initdata;
 469                 config.of_node = pdata->regulators[i].of_node;
 470
 471                 max77686->opmode[i] = regulators[i].enable_mask;
 472                 max77686->rdev[i] = regulator_register(&regulators[i], &config);
 473                 if (IS_ERR(max77686->rdev[i])) {
 474                         ret = PTR_ERR(max77686->rdev[i]);
 475                         dev_err(&pdev->dev,
 476                                 "regulator init failed for %d\n", i);
 477                         max77686->rdev[i] = NULL;
 478                         goto err;
 479                 }
 480         }
 481
 482         return 0;
 483 err:
 484         while (--i >= 0)
 485                 regulator_unregister(max77686->rdev[i]);
 486         return ret;
 487 }
 488
 489 static int max77686_pmic_remove(struct platform_device *pdev)
 490 {
 491         struct max77686_data *max77686 = platform_get_drvdata(pdev);
 492         int i;
 493
 494         for (i = 0; i < MAX77686_REGULATORS; i++)
 495                 regulator_unregister(max77686->rdev[i]);
 496
 497         return 0;
 498 }
 499
 500 static const struct platform_device_id max77686_pmic_id[] = {
 501         {"max77686-pmic", 0},
 502         { },
 503 };
 504 MODULE_DEVICE_TABLE(platform, max77686_pmic_id);
 505
 506 static struct platform_driver max77686_pmic_driver = {
 507         .driver = {
 508                 .name = "max77686-pmic",
 509                 .owner = THIS_MODULE,
 510         },
 511         .probe = max77686_pmic_probe,
 512         .remove = max77686_pmic_remove,
 513         .id_table = max77686_pmic_id,
 514 };
 515
 516 static int __init max77686_pmic_init(void)
 517 {
 518         return platform_driver_register(&max77686_pmic_driver);
 519 }
 520 subsys_initcall(max77686_pmic_init);
 521
 522 static void __exit max77686_pmic_cleanup(void)
 523 {
 524         platform_driver_unregister(&max77686_pmic_driver);
 525 }
 526 module_exit(max77686_pmic_cleanup);
 527
 528 MODULE_DESCRIPTION("MAXIM 77686 Regulator Driver");
 529 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
 530 MODULE_LICENSE("GPL");