drivers/regulator/ab3100.c

   1 /*
   2  * drivers/regulator/ab3100.c
   3  *
   4  * Copyright (C) 2008-2009 ST-Ericsson AB
   5  * License terms: GNU General Public License (GPL) version 2
   6  * Low-level control of the AB3100 IC Low Dropout (LDO)
   7  * regulators, external regulator and buck converter
   8  * Author: Mattias Wallin <mattias.wallin@stericsson.com>
   9  * Author: Linus Walleij <linus.walleij@stericsson.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/err.h>
  16 #include <linux/delay.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/regulator/driver.h>
  19 #include <linux/mfd/abx500.h>
  20
  21 /* LDO registers and some handy masking definitions for AB3100 */
  22 #define AB3100_LDO_A            0x40
  23 #define AB3100_LDO_C            0x41
  24 #define AB3100_LDO_D            0x42
  25 #define AB3100_LDO_E            0x43
  26 #define AB3100_LDO_E_SLEEP      0x44
  27 #define AB3100_LDO_F            0x45
  28 #define AB3100_LDO_G            0x46
  29 #define AB3100_LDO_H            0x47
  30 #define AB3100_LDO_H_SLEEP_MODE 0
  31 #define AB3100_LDO_H_SLEEP_EN   2
  32 #define AB3100_LDO_ON           4
  33 #define AB3100_LDO_H_VSEL_AC    5
  34 #define AB3100_LDO_K            0x48
  35 #define AB3100_LDO_EXT          0x49
  36 #define AB3100_BUCK             0x4A
  37 #define AB3100_BUCK_SLEEP       0x4B
  38 #define AB3100_REG_ON_MASK      0x10
  39
  40 /**
  41  * struct ab3100_regulator
  42  * A struct passed around the individual regulator functions
  43  * @platform_device: platform device holding this regulator
  44  * @dev: handle to the device
  45  * @plfdata: AB3100 platform data passed in at probe time
  46  * @regreg: regulator register number in the AB3100
  47  * @fixed_voltage: a fixed voltage for this regulator, if this
  48  *          0 the voltages array is used instead.
  49  * @typ_voltages: an array of available typical voltages for
  50  *          this regulator
  51  * @voltages_len: length of the array of available voltages
  52  */
  53 struct ab3100_regulator {
  54         struct regulator_dev *rdev;
  55         struct device *dev;
  56         struct ab3100_platform_data *plfdata;
  57         u8 regreg;
  58         int fixed_voltage;
  59         int const *typ_voltages;
  60         u8 voltages_len;
  61 };
  62
  63 /* The order in which registers are initialized */
  64 static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
  65         AB3100_LDO_A,
  66         AB3100_LDO_C,
  67         AB3100_LDO_E,
  68         AB3100_LDO_E_SLEEP,
  69         AB3100_LDO_F,
  70         AB3100_LDO_G,
  71         AB3100_LDO_H,
  72         AB3100_LDO_K,
  73         AB3100_LDO_EXT,
  74         AB3100_BUCK,
  75         AB3100_BUCK_SLEEP,
  76         AB3100_LDO_D,
  77 };
  78
  79 /* Preset (hardware defined) voltages for these regulators */
  80 #define LDO_A_VOLTAGE 2750000
  81 #define LDO_C_VOLTAGE 2650000
  82 #define LDO_D_VOLTAGE 2650000
  83
  84 static const int ldo_e_buck_typ_voltages[] = {
  85         1800000,
  86         1400000,
  87         1300000,
  88         1200000,
  89         1100000,
  90         1050000,
  91         900000,
  92 };
  93
  94 static const int ldo_f_typ_voltages[] = {
  95         1800000,
  96         1400000,
  97         1300000,
  98         1200000,
  99         1100000,
 100         1050000,
 101         2500000,
 102         2650000,
 103 };
 104
 105 static const int ldo_g_typ_voltages[] = {
 106         2850000,
 107         2750000,
 108         1800000,
 109         1500000,
 110 };
 111
 112 static const int ldo_h_typ_voltages[] = {
 113         2750000,
 114         1800000,
 115         1500000,
 116         1200000,
 117 };
 118
 119 static const int ldo_k_typ_voltages[] = {
 120         2750000,
 121         1800000,
 122 };
 123
 124
 125 /* The regulator devices */
 126 static struct ab3100_regulator
 127 ab3100_regulators[AB3100_NUM_REGULATORS] = {
 128         {
 129                 .regreg = AB3100_LDO_A,
 130                 .fixed_voltage = LDO_A_VOLTAGE,
 131         },
 132         {
 133                 .regreg = AB3100_LDO_C,
 134                 .fixed_voltage = LDO_C_VOLTAGE,
 135         },
 136         {
 137                 .regreg = AB3100_LDO_D,
 138                 .fixed_voltage = LDO_D_VOLTAGE,
 139         },
 140         {
 141                 .regreg = AB3100_LDO_E,
 142                 .typ_voltages = ldo_e_buck_typ_voltages,
 143                 .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
 144         },
 145         {
 146                 .regreg = AB3100_LDO_F,
 147                 .typ_voltages = ldo_f_typ_voltages,
 148                 .voltages_len = ARRAY_SIZE(ldo_f_typ_voltages),
 149         },
 150         {
 151                 .regreg = AB3100_LDO_G,
 152                 .typ_voltages = ldo_g_typ_voltages,
 153                 .voltages_len = ARRAY_SIZE(ldo_g_typ_voltages),
 154         },
 155         {
 156                 .regreg = AB3100_LDO_H,
 157                 .typ_voltages = ldo_h_typ_voltages,
 158                 .voltages_len = ARRAY_SIZE(ldo_h_typ_voltages),
 159         },
 160         {
 161                 .regreg = AB3100_LDO_K,
 162                 .typ_voltages = ldo_k_typ_voltages,
 163                 .voltages_len = ARRAY_SIZE(ldo_k_typ_voltages),
 164         },
 165         {
 166                 .regreg = AB3100_LDO_EXT,
 167                 /* No voltages for the external regulator */
 168         },
 169         {
 170                 .regreg = AB3100_BUCK,
 171                 .typ_voltages = ldo_e_buck_typ_voltages,
 172                 .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
 173         },
 174 };
 175
 176 /*
 177  * General functions for enable, disable and is_enabled used for
 178  * LDO: A,C,E,F,G,H,K,EXT and BUCK
 179  */
 180 static int ab3100_enable_regulator(struct regulator_dev *reg)
 181 {
 182         struct ab3100_regulator *abreg = reg->reg_data;
 183         int err;
 184         u8 regval;
 185
 186         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
 187                                                 &regval);
 188         if (err) {
 189                 dev_warn(&reg->dev, "failed to get regid %d value\n",
 190                          abreg->regreg);
 191                 return err;
 192         }
 193
 194         /* The regulator is already on, no reason to go further */
 195         if (regval & AB3100_REG_ON_MASK)
 196                 return 0;
 197
 198         regval |= AB3100_REG_ON_MASK;
 199
 200         err = abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
 201                                                 regval);
 202         if (err) {
 203                 dev_warn(&reg->dev, "failed to set regid %d value\n",
 204                          abreg->regreg);
 205                 return err;
 206         }
 207
 208         /* Per-regulator power on delay from spec */
 209         switch (abreg->regreg) {
 210         case AB3100_LDO_A: /* Fallthrough */
 211         case AB3100_LDO_C: /* Fallthrough */
 212         case AB3100_LDO_D: /* Fallthrough */
 213         case AB3100_LDO_E: /* Fallthrough */
 214         case AB3100_LDO_H: /* Fallthrough */
 215         case AB3100_LDO_K:
 216                 udelay(200);
 217                 break;
 218         case AB3100_LDO_F:
 219                 udelay(600);
 220                 break;
 221         case AB3100_LDO_G:
 222                 udelay(400);
 223                 break;
 224         case AB3100_BUCK:
 225                 mdelay(1);
 226                 break;
 227         default:
 228                 break;
 229         }
 230
 231         return 0;
 232 }
 233
 234 static int ab3100_disable_regulator(struct regulator_dev *reg)
 235 {
 236         struct ab3100_regulator *abreg = reg->reg_data;
 237         int err;
 238         u8 regval;
 239
 240         /*
 241          * LDO D is a special regulator. When it is disabled, the entire
 242          * system is shut down. So this is handled specially.
 243          */
 244         pr_info("Called ab3100_disable_regulator\n");
 245         if (abreg->regreg == AB3100_LDO_D) {
 246                 dev_info(&reg->dev, "disabling LDO D - shut down system\n");
 247                 /* Setting LDO D to 0x00 cuts the power to the SoC */
 248                 return abx500_set_register_interruptible(abreg->dev, 0,
 249                                                          AB3100_LDO_D, 0x00U);
 250         }
 251
 252         /*
 253          * All other regulators are handled here
 254          */
 255         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
 256                                                 &regval);
 257         if (err) {
 258                 dev_err(&reg->dev, "unable to get register 0x%x\n",
 259                         abreg->regreg);
 260                 return err;
 261         }
 262         regval &= ~AB3100_REG_ON_MASK;
 263         return abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg,
 264                                                  regval);
 265 }
 266
 267 static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
 268 {
 269         struct ab3100_regulator *abreg = reg->reg_data;
 270         u8 regval;
 271         int err;
 272
 273         err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg,
 274                                                 &regval);
 275         if (err) {
 276                 dev_err(&reg->dev, "unable to get register 0x%x\n",
 277                         abreg->regreg);
 278                 return err;
 279         }
 280
 281         return regval & AB3100_REG_ON_MASK;
 282 }
 283
 284 static int ab3100_list_voltage_regulator(struct regulator_dev *reg,
 285                                          unsigned selector)
 286 {
 287         struct ab3100_regulator *abreg = reg->reg_data;
 288
 289         if (selector > abreg->voltages_len)
 290                 return -EINVAL;
 291         return abreg->typ_voltages[selector];
 292 }
 293
 294 static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
 295 {
 296         struct ab3100_regulator *abreg = reg->reg_data;
 297         u8 regval;
 298         int err;
 299
 300         /* Return the voltage for fixed regulators immediately */
 301         if (abreg->fixed_voltage)
 302                 return abreg->fixed_voltage;
 303
 304         /*
 305          * For variable types, read out setting and index into
 306          * supplied voltage list.
 307          */
 308         err = abx500_get_register_interruptible(abreg->dev, 0,
 309                                                 abreg->regreg, &regval);
 310         if (err) {
 311                 dev_warn(&reg->dev,
 312                          "failed to get regulator value in register %02x\n",
 313                          abreg->regreg);
 314                 return err;
 315         }
 316
 317         /* The 3 highest bits index voltages */
 318         regval &= 0xE0;
 319         regval >>= 5;
 320
 321         if (regval > abreg->voltages_len) {
 322                 dev_err(&reg->dev,
 323                         "regulator register %02x contains an illegal voltage setting\n",
 324                         abreg->regreg);
 325                 return -EINVAL;
 326         }
 327
 328         return abreg->typ_voltages[regval];
 329 }
 330
 331 static int ab3100_get_best_voltage_index(struct regulator_dev *reg,
 332                                    int min_uV, int max_uV)
 333 {
 334         struct ab3100_regulator *abreg = reg->reg_data;
 335         int i;
 336         int bestmatch;
 337         int bestindex;
 338
 339         /*
 340          * Locate the minimum voltage fitting the criteria on
 341          * this regulator. The switchable voltages are not
 342          * in strict falling order so we need to check them
 343          * all for the best match.
 344          */
 345         bestmatch = INT_MAX;
 346         bestindex = -1;
 347         for (i = 0; i < abreg->voltages_len; i++) {
 348                 if (abreg->typ_voltages[i] <= max_uV &&
 349                     abreg->typ_voltages[i] >= min_uV &&
 350                     abreg->typ_voltages[i] < bestmatch) {
 351                         bestmatch = abreg->typ_voltages[i];
 352                         bestindex = i;
 353                 }
 354         }
 355
 356         if (bestindex < 0) {
 357                 dev_warn(&reg->dev, "requested %d<=x<=%d uV, out of range!\n",
 358                          min_uV, max_uV);
 359                 return -EINVAL;
 360         }
 361         return bestindex;
 362 }
 363
 364 static int ab3100_set_voltage_regulator(struct regulator_dev *reg,
 365                                         int min_uV, int max_uV)
 366 {
 367         struct ab3100_regulator *abreg = reg->reg_data;
 368         u8 regval;
 369         int err;
 370         int bestindex;
 371
 372         bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV);
 373         if (bestindex < 0)
 374                 return bestindex;
 375
 376         err = abx500_get_register_interruptible(abreg->dev, 0,
 377                                                 abreg->regreg, &regval);
 378         if (err) {
 379                 dev_warn(&reg->dev,
 380                          "failed to get regulator register %02x\n",
 381                          abreg->regreg);
 382                 return err;
 383         }
 384
 385         /* The highest three bits control the variable regulators */
 386         regval &= ~0xE0;
 387         regval |= (bestindex << 5);
 388
 389         err = abx500_set_register_interruptible(abreg->dev, 0,
 390                                                 abreg->regreg, regval);
 391         if (err)
 392                 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
 393                         abreg->regreg);
 394
 395         return err;
 396 }
 397
 398 static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
 399                                                 int uV)
 400 {
 401         struct ab3100_regulator *abreg = reg->reg_data;
 402         u8 regval;
 403         int err;
 404         int bestindex;
 405         u8 targetreg;
 406
 407         if (abreg->regreg == AB3100_LDO_E)
 408                 targetreg = AB3100_LDO_E_SLEEP;
 409         else if (abreg->regreg == AB3100_BUCK)
 410                 targetreg = AB3100_BUCK_SLEEP;
 411         else
 412                 return -EINVAL;
 413
 414         /* LDO E and BUCK have special suspend voltages you can set */
 415         bestindex = ab3100_get_best_voltage_index(reg, uV, uV);
 416
 417         err = abx500_get_register_interruptible(abreg->dev, 0,
 418                                                 targetreg, &regval);
 419         if (err) {
 420                 dev_warn(&reg->dev,
 421                          "failed to get regulator register %02x\n",
 422                          targetreg);
 423                 return err;
 424         }
 425
 426         /* The highest three bits control the variable regulators */
 427         regval &= ~0xE0;
 428         regval |= (bestindex << 5);
 429
 430         err = abx500_set_register_interruptible(abreg->dev, 0,
 431                                                 targetreg, regval);
 432         if (err)
 433                 dev_warn(&reg->dev, "failed to set regulator register %02x\n",
 434                         abreg->regreg);
 435
 436         return err;
 437 }
 438
 439 /*
 440  * The external regulator can just define a fixed voltage.
 441  */
 442 static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
 443 {
 444         struct ab3100_regulator *abreg = reg->reg_data;
 445
 446         return abreg->plfdata->external_voltage;
 447 }
 448
 449 static struct regulator_ops regulator_ops_fixed = {
 450         .enable      = ab3100_enable_regulator,
 451         .disable     = ab3100_disable_regulator,
 452         .is_enabled  = ab3100_is_enabled_regulator,
 453         .get_voltage = ab3100_get_voltage_regulator,
 454 };
 455
 456 static struct regulator_ops regulator_ops_variable = {
 457         .enable      = ab3100_enable_regulator,
 458         .disable     = ab3100_disable_regulator,
 459         .is_enabled  = ab3100_is_enabled_regulator,
 460         .get_voltage = ab3100_get_voltage_regulator,
 461         .set_voltage = ab3100_set_voltage_regulator,
 462         .list_voltage = ab3100_list_voltage_regulator,
 463 };
 464
 465 static struct regulator_ops regulator_ops_variable_sleepable = {
 466         .enable      = ab3100_enable_regulator,
 467         .disable     = ab3100_disable_regulator,
 468         .is_enabled  = ab3100_is_enabled_regulator,
 469         .get_voltage = ab3100_get_voltage_regulator,
 470         .set_voltage = ab3100_set_voltage_regulator,
 471         .set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
 472         .list_voltage = ab3100_list_voltage_regulator,
 473 };
 474
 475 /*
 476  * LDO EXT is an external regulator so it is really
 477  * not possible to set any voltage locally here, AB3100
 478  * is an on/off switch plain an simple. The external
 479  * voltage is defined in the board set-up if any.
 480  */
 481 static struct regulator_ops regulator_ops_external = {
 482         .enable      = ab3100_enable_regulator,
 483         .disable     = ab3100_disable_regulator,
 484         .is_enabled  = ab3100_is_enabled_regulator,
 485         .get_voltage = ab3100_get_voltage_regulator_external,
 486 };
 487
 488 static struct regulator_desc
 489 ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
 490         {
 491                 .name = "LDO_A",
 492                 .id   = AB3100_LDO_A,
 493                 .ops  = &regulator_ops_fixed,
 494                 .type = REGULATOR_VOLTAGE,
 495                 .owner = THIS_MODULE,
 496         },
 497         {
 498                 .name = "LDO_C",
 499                 .id   = AB3100_LDO_C,
 500                 .ops  = &regulator_ops_fixed,
 501                 .type = REGULATOR_VOLTAGE,
 502                 .owner = THIS_MODULE,
 503         },
 504         {
 505                 .name = "LDO_D",
 506                 .id   = AB3100_LDO_D,
 507                 .ops  = &regulator_ops_fixed,
 508                 .type = REGULATOR_VOLTAGE,
 509                 .owner = THIS_MODULE,
 510         },
 511         {
 512                 .name = "LDO_E",
 513                 .id   = AB3100_LDO_E,
 514                 .ops  = &regulator_ops_variable_sleepable,
 515                 .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
 516                 .type = REGULATOR_VOLTAGE,
 517                 .owner = THIS_MODULE,
 518         },
 519         {
 520                 .name = "LDO_F",
 521                 .id   = AB3100_LDO_F,
 522                 .ops  = &regulator_ops_variable,
 523                 .n_voltages = ARRAY_SIZE(ldo_f_typ_voltages),
 524                 .type = REGULATOR_VOLTAGE,
 525                 .owner = THIS_MODULE,
 526         },
 527         {
 528                 .name = "LDO_G",
 529                 .id   = AB3100_LDO_G,
 530                 .ops  = &regulator_ops_variable,
 531                 .n_voltages = ARRAY_SIZE(ldo_g_typ_voltages),
 532                 .type = REGULATOR_VOLTAGE,
 533                 .owner = THIS_MODULE,
 534         },
 535         {
 536                 .name = "LDO_H",
 537                 .id   = AB3100_LDO_H,
 538                 .ops  = &regulator_ops_variable,
 539                 .n_voltages = ARRAY_SIZE(ldo_h_typ_voltages),
 540                 .type = REGULATOR_VOLTAGE,
 541                 .owner = THIS_MODULE,
 542         },
 543         {
 544                 .name = "LDO_K",
 545                 .id   = AB3100_LDO_K,
 546                 .ops  = &regulator_ops_variable,
 547                 .n_voltages = ARRAY_SIZE(ldo_k_typ_voltages),
 548                 .type = REGULATOR_VOLTAGE,
 549                 .owner = THIS_MODULE,
 550         },
 551         {
 552                 .name = "LDO_EXT",
 553                 .id   = AB3100_LDO_EXT,
 554                 .ops  = &regulator_ops_external,
 555                 .type = REGULATOR_VOLTAGE,
 556                 .owner = THIS_MODULE,
 557         },
 558         {
 559                 .name = "BUCK",
 560                 .id   = AB3100_BUCK,
 561                 .ops  = &regulator_ops_variable_sleepable,
 562                 .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
 563                 .type = REGULATOR_VOLTAGE,
 564                 .owner = THIS_MODULE,
 565         },
 566 };
 567
 568 /*
 569  * NOTE: the following functions are regulators pluralis - it is the
 570  * binding to the AB3100 core driver and the parent platform device
 571  * for all the different regulators.
 572  */
 573
 574 static int __devinit ab3100_regulators_probe(struct platform_device *pdev)
 575 {
 576         struct ab3100_platform_data *plfdata = pdev->dev.platform_data;
 577         int err = 0;
 578         u8 data;
 579         int i;
 580
 581         /* Check chip state */
 582         err = abx500_get_register_interruptible(&pdev->dev, 0,
 583                                                 AB3100_LDO_D, &data);
 584         if (err) {
 585                 dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
 586                 return err;
 587         }
 588         if (data & 0x10)
 589                 dev_notice(&pdev->dev,
 590                            "chip is already in active mode (Warm start)\n");
 591         else
 592                 dev_notice(&pdev->dev,
 593                            "chip is in inactive mode (Cold start)\n");
 594
 595         /* Set up regulators */
 596         for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
 597                 err = abx500_set_register_interruptible(&pdev->dev, 0,
 598                                         ab3100_reg_init_order[i],
 599                                         plfdata->reg_initvals[i]);
 600                 if (err) {
 601                         dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
 602                                 err);
 603                         return err;
 604                 }
 605         }
 606
 607         /* Register the regulators */
 608         for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
 609                 struct ab3100_regulator *reg = &ab3100_regulators[i];
 610                 struct regulator_dev *rdev;
 611
 612                 /*
 613                  * Initialize per-regulator struct.
 614                  * Inherit platform data, this comes down from the
 615                  * i2c boarddata, from the machine. So if you want to
 616                  * see what it looks like for a certain machine, go
 617                  * into the machine I2C setup.
 618                  */
 619                 reg->dev = &pdev->dev;
 620                 reg->plfdata = plfdata;
 621
 622                 /*
 623                  * Register the regulator, pass around
 624                  * the ab3100_regulator struct
 625                  */
 626                 rdev = regulator_register(&ab3100_regulator_desc[i],
 627                                           &pdev->dev,
 628                                           &plfdata->reg_constraints[i],
 629                                           reg);
 630
 631                 if (IS_ERR(rdev)) {
 632                         err = PTR_ERR(rdev);
 633                         dev_err(&pdev->dev,
 634                                 "%s: failed to register regulator %s err %d\n",
 635                                 __func__, ab3100_regulator_desc[i].name,
 636                                 err);
 637                         i--;
 638                         /* remove the already registered regulators */
 639                         while (i > 0) {
 640                                 regulator_unregister(ab3100_regulators[i].rdev);
 641                                 i--;
 642                         }
 643                         return err;
 644                 }
 645
 646                 /* Then set a pointer back to the registered regulator */
 647                 reg->rdev = rdev;
 648         }
 649
 650         return 0;
 651 }
 652
 653 static int __devexit ab3100_regulators_remove(struct platform_device *pdev)
 654 {
 655         int i;
 656
 657         for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
 658                 struct ab3100_regulator *reg = &ab3100_regulators[i];
 659
 660                 regulator_unregister(reg->rdev);
 661         }
 662         return 0;
 663 }
 664
 665 static struct platform_driver ab3100_regulators_driver = {
 666         .driver = {
 667                 .name  = "ab3100-regulators",
 668                 .owner = THIS_MODULE,
 669         },
 670         .probe = ab3100_regulators_probe,
 671         .remove = __devexit_p(ab3100_regulators_remove),
 672 };
 673
 674 static __init int ab3100_regulators_init(void)
 675 {
 676         return platform_driver_register(&ab3100_regulators_driver);
 677 }
 678
 679 static __exit void ab3100_regulators_exit(void)
 680 {
 681         platform_driver_unregister(&ab3100_regulators_driver);
 682 }
 683
 684 subsys_initcall(ab3100_regulators_init);
 685 module_exit(ab3100_regulators_exit);
 686
 687 MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
 688 MODULE_DESCRIPTION("AB3100 Regulator driver");
 689 MODULE_LICENSE("GPL");
 690 MODULE_ALIAS("platform:ab3100-regulators");