drivers/regulator/core.c

   1 /*
   2  * core.c  --  Voltage/Current Regulator framework.
   3  *
   4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
   5  * Copyright 2008 SlimLogic Ltd.
   6  *
   7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
   8  *
   9  *  This program is free software; you can redistribute  it and/or modify it
  10  *  under  the terms of  the GNU General  Public License as published by the
  11  *  Free Software Foundation;  either version 2 of the  License, or (at your
  12  *  option) any later version.
  13  *
  14  */
  15
  16 #define pr_fmt(fmt) "%s: " fmt, __func__
  17
  18 #include <linux/kernel.h>
  19 #include <linux/init.h>
  20 #include <linux/device.h>
  21 #include <linux/slab.h>
  22 #include <linux/err.h>
  23 #include <linux/mutex.h>
  24 #include <linux/suspend.h>
  25 #include <linux/delay.h>
  26 #include <linux/regulator/consumer.h>
  27 #include <linux/regulator/driver.h>
  28 #include <linux/regulator/machine.h>
  29
  30 #define CREATE_TRACE_POINTS
  31 #include <trace/events/regulator.h>
  32
  33 #include "dummy.h"
  34
  35 #define REGULATOR_VERSION "0.5"
  36
  37 static DEFINE_MUTEX(regulator_list_mutex);
  38 static LIST_HEAD(regulator_list);
  39 static LIST_HEAD(regulator_map_list);
  40 static int has_full_constraints;
  41 static bool board_wants_dummy_regulator;
  42
  43 /*
  44  * struct regulator_map
  45  *
  46  * Used to provide symbolic supply names to devices.
  47  */
  48 struct regulator_map {
  49         struct list_head list;
  50         const char *dev_name;   /* The dev_name() for the consumer */
  51         const char *supply;
  52         struct regulator_dev *regulator;
  53 };
  54
  55 /*
  56  * struct regulator
  57  *
  58  * One for each consumer device.
  59  */
  60 struct regulator {
  61         struct device *dev;
  62         struct list_head list;
  63         int uA_load;
  64         int min_uV;
  65         int max_uV;
  66         char *supply_name;
  67         struct device_attribute dev_attr;
  68         struct regulator_dev *rdev;
  69 };
  70
  71 static int _regulator_is_enabled(struct regulator_dev *rdev);
  72 static int _regulator_disable(struct regulator_dev *rdev,
  73                 struct regulator_dev **supply_rdev_ptr);
  74 static int _regulator_get_voltage(struct regulator_dev *rdev);
  75 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  76 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  77 static void _notifier_call_chain(struct regulator_dev *rdev,
  78                                   unsigned long event, void *data);
  79
  80 static const char *rdev_get_name(struct regulator_dev *rdev)
  81 {
  82         if (rdev->constraints && rdev->constraints->name)
  83                 return rdev->constraints->name;
  84         else if (rdev->desc->name)
  85                 return rdev->desc->name;
  86         else
  87                 return "";
  88 }
  89
  90 /* gets the regulator for a given consumer device */
  91 static struct regulator *get_device_regulator(struct device *dev)
  92 {
  93         struct regulator *regulator = NULL;
  94         struct regulator_dev *rdev;
  95
  96         mutex_lock(&regulator_list_mutex);
  97         list_for_each_entry(rdev, &regulator_list, list) {
  98                 mutex_lock(&rdev->mutex);
  99                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
 100                         if (regulator->dev == dev) {
 101                                 mutex_unlock(&rdev->mutex);
 102                                 mutex_unlock(&regulator_list_mutex);
 103                                 return regulator;
 104                         }
 105                 }
 106                 mutex_unlock(&rdev->mutex);
 107         }
 108         mutex_unlock(&regulator_list_mutex);
 109         return NULL;
 110 }
 111
 112 /* Platform voltage constraint check */
 113 static int regulator_check_voltage(struct regulator_dev *rdev,
 114                                    int *min_uV, int *max_uV)
 115 {
 116         BUG_ON(*min_uV > *max_uV);
 117
 118         if (!rdev->constraints) {
 119                 pr_err("no constraints for %s\n", rdev_get_name(rdev));
 120                 return -ENODEV;
 121         }
 122         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 123                 pr_err("operation not allowed for %s\n", rdev_get_name(rdev));
 124                 return -EPERM;
 125         }
 126
 127         if (*max_uV > rdev->constraints->max_uV)
 128                 *max_uV = rdev->constraints->max_uV;
 129         if (*min_uV < rdev->constraints->min_uV)
 130                 *min_uV = rdev->constraints->min_uV;
 131
 132         if (*min_uV > *max_uV)
 133                 return -EINVAL;
 134
 135         return 0;
 136 }
 137
 138 /* current constraint check */
 139 static int regulator_check_current_limit(struct regulator_dev *rdev,
 140                                         int *min_uA, int *max_uA)
 141 {
 142         BUG_ON(*min_uA > *max_uA);
 143
 144         if (!rdev->constraints) {
 145                 pr_err("no constraints for %s\n", rdev_get_name(rdev));
 146                 return -ENODEV;
 147         }
 148         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 149                 pr_err("operation not allowed for %s\n", rdev_get_name(rdev));
 150                 return -EPERM;
 151         }
 152
 153         if (*max_uA > rdev->constraints->max_uA)
 154                 *max_uA = rdev->constraints->max_uA;
 155         if (*min_uA < rdev->constraints->min_uA)
 156                 *min_uA = rdev->constraints->min_uA;
 157
 158         if (*min_uA > *max_uA)
 159                 return -EINVAL;
 160
 161         return 0;
 162 }
 163
 164 /* operating mode constraint check */
 165 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
 166 {
 167         switch (mode) {
 168         case REGULATOR_MODE_FAST:
 169         case REGULATOR_MODE_NORMAL:
 170         case REGULATOR_MODE_IDLE:
 171         case REGULATOR_MODE_STANDBY:
 172                 break;
 173         default:
 174                 return -EINVAL;
 175         }
 176
 177         if (!rdev->constraints) {
 178                 pr_err("no constraints for %s\n", rdev_get_name(rdev));
 179                 return -ENODEV;
 180         }
 181         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 182                 pr_err("operation not allowed for %s\n", rdev_get_name(rdev));
 183                 return -EPERM;
 184         }
 185         if (!(rdev->constraints->valid_modes_mask & mode)) {
 186                 pr_err("invalid mode %x for %s\n", mode, rdev_get_name(rdev));
 187                 return -EINVAL;
 188         }
 189         return 0;
 190 }
 191
 192 /* dynamic regulator mode switching constraint check */
 193 static int regulator_check_drms(struct regulator_dev *rdev)
 194 {
 195         if (!rdev->constraints) {
 196                 pr_err("no constraints for %s\n", rdev_get_name(rdev));
 197                 return -ENODEV;
 198         }
 199         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 200                 pr_err("operation not allowed for %s\n", rdev_get_name(rdev));
 201                 return -EPERM;
 202         }
 203         return 0;
 204 }
 205
 206 static ssize_t device_requested_uA_show(struct device *dev,
 207                              struct device_attribute *attr, char *buf)
 208 {
 209         struct regulator *regulator;
 210
 211         regulator = get_device_regulator(dev);
 212         if (regulator == NULL)
 213                 return 0;
 214
 215         return sprintf(buf, "%d\n", regulator->uA_load);
 216 }
 217
 218 static ssize_t regulator_uV_show(struct device *dev,
 219                                 struct device_attribute *attr, char *buf)
 220 {
 221         struct regulator_dev *rdev = dev_get_drvdata(dev);
 222         ssize_t ret;
 223
 224         mutex_lock(&rdev->mutex);
 225         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 226         mutex_unlock(&rdev->mutex);
 227
 228         return ret;
 229 }
 230 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 231
 232 static ssize_t regulator_uA_show(struct device *dev,
 233                                 struct device_attribute *attr, char *buf)
 234 {
 235         struct regulator_dev *rdev = dev_get_drvdata(dev);
 236
 237         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 238 }
 239 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 240
 241 static ssize_t regulator_name_show(struct device *dev,
 242                              struct device_attribute *attr, char *buf)
 243 {
 244         struct regulator_dev *rdev = dev_get_drvdata(dev);
 245
 246         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 247 }
 248
 249 static ssize_t regulator_print_opmode(char *buf, int mode)
 250 {
 251         switch (mode) {
 252         case REGULATOR_MODE_FAST:
 253                 return sprintf(buf, "fast\n");
 254         case REGULATOR_MODE_NORMAL:
 255                 return sprintf(buf, "normal\n");
 256         case REGULATOR_MODE_IDLE:
 257                 return sprintf(buf, "idle\n");
 258         case REGULATOR_MODE_STANDBY:
 259                 return sprintf(buf, "standby\n");
 260         }
 261         return sprintf(buf, "unknown\n");
 262 }
 263
 264 static ssize_t regulator_opmode_show(struct device *dev,
 265                                     struct device_attribute *attr, char *buf)
 266 {
 267         struct regulator_dev *rdev = dev_get_drvdata(dev);
 268
 269         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 270 }
 271 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 272
 273 static ssize_t regulator_print_state(char *buf, int state)
 274 {
 275         if (state > 0)
 276                 return sprintf(buf, "enabled\n");
 277         else if (state == 0)
 278                 return sprintf(buf, "disabled\n");
 279         else
 280                 return sprintf(buf, "unknown\n");
 281 }
 282
 283 static ssize_t regulator_state_show(struct device *dev,
 284                                    struct device_attribute *attr, char *buf)
 285 {
 286         struct regulator_dev *rdev = dev_get_drvdata(dev);
 287         ssize_t ret;
 288
 289         mutex_lock(&rdev->mutex);
 290         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 291         mutex_unlock(&rdev->mutex);
 292
 293         return ret;
 294 }
 295 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 296
 297 static ssize_t regulator_status_show(struct device *dev,
 298                                    struct device_attribute *attr, char *buf)
 299 {
 300         struct regulator_dev *rdev = dev_get_drvdata(dev);
 301         int status;
 302         char *label;
 303
 304         status = rdev->desc->ops->get_status(rdev);
 305         if (status < 0)
 306                 return status;
 307
 308         switch (status) {
 309         case REGULATOR_STATUS_OFF:
 310                 label = "off";
 311                 break;
 312         case REGULATOR_STATUS_ON:
 313                 label = "on";
 314                 break;
 315         case REGULATOR_STATUS_ERROR:
 316                 label = "error";
 317                 break;
 318         case REGULATOR_STATUS_FAST:
 319                 label = "fast";
 320                 break;
 321         case REGULATOR_STATUS_NORMAL:
 322                 label = "normal";
 323                 break;
 324         case REGULATOR_STATUS_IDLE:
 325                 label = "idle";
 326                 break;
 327         case REGULATOR_STATUS_STANDBY:
 328                 label = "standby";
 329                 break;
 330         default:
 331                 return -ERANGE;
 332         }
 333
 334         return sprintf(buf, "%s\n", label);
 335 }
 336 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 337
 338 static ssize_t regulator_min_uA_show(struct device *dev,
 339                                     struct device_attribute *attr, char *buf)
 340 {
 341         struct regulator_dev *rdev = dev_get_drvdata(dev);
 342
 343         if (!rdev->constraints)
 344                 return sprintf(buf, "constraint not defined\n");
 345
 346         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 347 }
 348 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 349
 350 static ssize_t regulator_max_uA_show(struct device *dev,
 351                                     struct device_attribute *attr, char *buf)
 352 {
 353         struct regulator_dev *rdev = dev_get_drvdata(dev);
 354
 355         if (!rdev->constraints)
 356                 return sprintf(buf, "constraint not defined\n");
 357
 358         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 359 }
 360 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 361
 362 static ssize_t regulator_min_uV_show(struct device *dev,
 363                                     struct device_attribute *attr, char *buf)
 364 {
 365         struct regulator_dev *rdev = dev_get_drvdata(dev);
 366
 367         if (!rdev->constraints)
 368                 return sprintf(buf, "constraint not defined\n");
 369
 370         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 371 }
 372 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 373
 374 static ssize_t regulator_max_uV_show(struct device *dev,
 375                                     struct device_attribute *attr, char *buf)
 376 {
 377         struct regulator_dev *rdev = dev_get_drvdata(dev);
 378
 379         if (!rdev->constraints)
 380                 return sprintf(buf, "constraint not defined\n");
 381
 382         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 383 }
 384 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 385
 386 static ssize_t regulator_total_uA_show(struct device *dev,
 387                                       struct device_attribute *attr, char *buf)
 388 {
 389         struct regulator_dev *rdev = dev_get_drvdata(dev);
 390         struct regulator *regulator;
 391         int uA = 0;
 392
 393         mutex_lock(&rdev->mutex);
 394         list_for_each_entry(regulator, &rdev->consumer_list, list)
 395                 uA += regulator->uA_load;
 396         mutex_unlock(&rdev->mutex);
 397         return sprintf(buf, "%d\n", uA);
 398 }
 399 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 400
 401 static ssize_t regulator_num_users_show(struct device *dev,
 402                                       struct device_attribute *attr, char *buf)
 403 {
 404         struct regulator_dev *rdev = dev_get_drvdata(dev);
 405         return sprintf(buf, "%d\n", rdev->use_count);
 406 }
 407
 408 static ssize_t regulator_type_show(struct device *dev,
 409                                   struct device_attribute *attr, char *buf)
 410 {
 411         struct regulator_dev *rdev = dev_get_drvdata(dev);
 412
 413         switch (rdev->desc->type) {
 414         case REGULATOR_VOLTAGE:
 415                 return sprintf(buf, "voltage\n");
 416         case REGULATOR_CURRENT:
 417                 return sprintf(buf, "current\n");
 418         }
 419         return sprintf(buf, "unknown\n");
 420 }
 421
 422 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 423                                 struct device_attribute *attr, char *buf)
 424 {
 425         struct regulator_dev *rdev = dev_get_drvdata(dev);
 426
 427         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 428 }
 429 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 430                 regulator_suspend_mem_uV_show, NULL);
 431
 432 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 433                                 struct device_attribute *attr, char *buf)
 434 {
 435         struct regulator_dev *rdev = dev_get_drvdata(dev);
 436
 437         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 438 }
 439 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 440                 regulator_suspend_disk_uV_show, NULL);
 441
 442 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 443                                 struct device_attribute *attr, char *buf)
 444 {
 445         struct regulator_dev *rdev = dev_get_drvdata(dev);
 446
 447         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 448 }
 449 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 450                 regulator_suspend_standby_uV_show, NULL);
 451
 452 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 453                                 struct device_attribute *attr, char *buf)
 454 {
 455         struct regulator_dev *rdev = dev_get_drvdata(dev);
 456
 457         return regulator_print_opmode(buf,
 458                 rdev->constraints->state_mem.mode);
 459 }
 460 static DEVICE_ATTR(suspend_mem_mode, 0444,
 461                 regulator_suspend_mem_mode_show, NULL);
 462
 463 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 464                                 struct device_attribute *attr, char *buf)
 465 {
 466         struct regulator_dev *rdev = dev_get_drvdata(dev);
 467
 468         return regulator_print_opmode(buf,
 469                 rdev->constraints->state_disk.mode);
 470 }
 471 static DEVICE_ATTR(suspend_disk_mode, 0444,
 472                 regulator_suspend_disk_mode_show, NULL);
 473
 474 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 475                                 struct device_attribute *attr, char *buf)
 476 {
 477         struct regulator_dev *rdev = dev_get_drvdata(dev);
 478
 479         return regulator_print_opmode(buf,
 480                 rdev->constraints->state_standby.mode);
 481 }
 482 static DEVICE_ATTR(suspend_standby_mode, 0444,
 483                 regulator_suspend_standby_mode_show, NULL);
 484
 485 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 486                                    struct device_attribute *attr, char *buf)
 487 {
 488         struct regulator_dev *rdev = dev_get_drvdata(dev);
 489
 490         return regulator_print_state(buf,
 491                         rdev->constraints->state_mem.enabled);
 492 }
 493 static DEVICE_ATTR(suspend_mem_state, 0444,
 494                 regulator_suspend_mem_state_show, NULL);
 495
 496 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 497                                    struct device_attribute *attr, char *buf)
 498 {
 499         struct regulator_dev *rdev = dev_get_drvdata(dev);
 500
 501         return regulator_print_state(buf,
 502                         rdev->constraints->state_disk.enabled);
 503 }
 504 static DEVICE_ATTR(suspend_disk_state, 0444,
 505                 regulator_suspend_disk_state_show, NULL);
 506
 507 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 508                                    struct device_attribute *attr, char *buf)
 509 {
 510         struct regulator_dev *rdev = dev_get_drvdata(dev);
 511
 512         return regulator_print_state(buf,
 513                         rdev->constraints->state_standby.enabled);
 514 }
 515 static DEVICE_ATTR(suspend_standby_state, 0444,
 516                 regulator_suspend_standby_state_show, NULL);
 517
 518
 519 /*
 520  * These are the only attributes are present for all regulators.
 521  * Other attributes are a function of regulator functionality.
 522  */
 523 static struct device_attribute regulator_dev_attrs[] = {
 524         __ATTR(name, 0444, regulator_name_show, NULL),
 525         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
 526         __ATTR(type, 0444, regulator_type_show, NULL),
 527         __ATTR_NULL,
 528 };
 529
 530 static void regulator_dev_release(struct device *dev)
 531 {
 532         struct regulator_dev *rdev = dev_get_drvdata(dev);
 533         kfree(rdev);
 534 }
 535
 536 static struct class regulator_class = {
 537         .name = "regulator",
 538         .dev_release = regulator_dev_release,
 539         .dev_attrs = regulator_dev_attrs,
 540 };
 541
 542 /* Calculate the new optimum regulator operating mode based on the new total
 543  * consumer load. All locks held by caller */
 544 static void drms_uA_update(struct regulator_dev *rdev)
 545 {
 546         struct regulator *sibling;
 547         int current_uA = 0, output_uV, input_uV, err;
 548         unsigned int mode;
 549
 550         err = regulator_check_drms(rdev);
 551         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 552             !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
 553                 return;
 554
 555         /* get output voltage */
 556         output_uV = rdev->desc->ops->get_voltage(rdev);
 557         if (output_uV <= 0)
 558                 return;
 559
 560         /* get input voltage */
 561         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
 562                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
 563         else
 564                 input_uV = rdev->constraints->input_uV;
 565         if (input_uV <= 0)
 566                 return;
 567
 568         /* calc total requested load */
 569         list_for_each_entry(sibling, &rdev->consumer_list, list)
 570                 current_uA += sibling->uA_load;
 571
 572         /* now get the optimum mode for our new total regulator load */
 573         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 574                                                   output_uV, current_uA);
 575
 576         /* check the new mode is allowed */
 577         err = regulator_check_mode(rdev, mode);
 578         if (err == 0)
 579                 rdev->desc->ops->set_mode(rdev, mode);
 580 }
 581
 582 static int suspend_set_state(struct regulator_dev *rdev,
 583         struct regulator_state *rstate)
 584 {
 585         int ret = 0;
 586         bool can_set_state;
 587
 588         can_set_state = rdev->desc->ops->set_suspend_enable &&
 589                 rdev->desc->ops->set_suspend_disable;
 590
 591         /* If we have no suspend mode configration don't set anything;
 592          * only warn if the driver actually makes the suspend mode
 593          * configurable.
 594          */
 595         if (!rstate->enabled && !rstate->disabled) {
 596                 if (can_set_state)
 597                         pr_warning("No configuration for %s\n",
 598                                    rdev_get_name(rdev));
 599                 return 0;
 600         }
 601
 602         if (rstate->enabled && rstate->disabled) {
 603                 pr_err("invalid configuration for %s\n", rdev_get_name(rdev));
 604                 return -EINVAL;
 605         }
 606
 607         if (!can_set_state) {
 608                 pr_err("no way to set suspend state\n");
 609                 return -EINVAL;
 610         }
 611
 612         if (rstate->enabled)
 613                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 614         else
 615                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 616         if (ret < 0) {
 617                 pr_err("failed to enabled/disable\n");
 618                 return ret;
 619         }
 620
 621         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 622                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 623                 if (ret < 0) {
 624                         pr_err("failed to set voltage\n");
 625                         return ret;
 626                 }
 627         }
 628
 629         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 630                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 631                 if (ret < 0) {
 632                         pr_err("failed to set mode\n");
 633                         return ret;
 634                 }
 635         }
 636         return ret;
 637 }
 638
 639 /* locks held by caller */
 640 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 641 {
 642         if (!rdev->constraints)
 643                 return -EINVAL;
 644
 645         switch (state) {
 646         case PM_SUSPEND_STANDBY:
 647                 return suspend_set_state(rdev,
 648                         &rdev->constraints->state_standby);
 649         case PM_SUSPEND_MEM:
 650                 return suspend_set_state(rdev,
 651                         &rdev->constraints->state_mem);
 652         case PM_SUSPEND_MAX:
 653                 return suspend_set_state(rdev,
 654                         &rdev->constraints->state_disk);
 655         default:
 656                 return -EINVAL;
 657         }
 658 }
 659
 660 static void print_constraints(struct regulator_dev *rdev)
 661 {
 662         struct regulation_constraints *constraints = rdev->constraints;
 663         char buf[80] = "";
 664         int count = 0;
 665         int ret;
 666
 667         if (constraints->min_uV && constraints->max_uV) {
 668                 if (constraints->min_uV == constraints->max_uV)
 669                         count += sprintf(buf + count, "%d mV ",
 670                                          constraints->min_uV / 1000);
 671                 else
 672                         count += sprintf(buf + count, "%d <--> %d mV ",
 673                                          constraints->min_uV / 1000,
 674                                          constraints->max_uV / 1000);
 675         }
 676
 677         if (!constraints->min_uV ||
 678             constraints->min_uV != constraints->max_uV) {
 679                 ret = _regulator_get_voltage(rdev);
 680                 if (ret > 0)
 681                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 682         }
 683
 684         if (constraints->min_uA && constraints->max_uA) {
 685                 if (constraints->min_uA == constraints->max_uA)
 686                         count += sprintf(buf + count, "%d mA ",
 687                                          constraints->min_uA / 1000);
 688                 else
 689                         count += sprintf(buf + count, "%d <--> %d mA ",
 690                                          constraints->min_uA / 1000,
 691                                          constraints->max_uA / 1000);
 692         }
 693
 694         if (!constraints->min_uA ||
 695             constraints->min_uA != constraints->max_uA) {
 696                 ret = _regulator_get_current_limit(rdev);
 697                 if (ret > 0)
 698                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
 699         }
 700
 701         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 702                 count += sprintf(buf + count, "fast ");
 703         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 704                 count += sprintf(buf + count, "normal ");
 705         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 706                 count += sprintf(buf + count, "idle ");
 707         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 708                 count += sprintf(buf + count, "standby");
 709
 710         printk(KERN_INFO "regulator: %s: %s\n", rdev_get_name(rdev), buf);
 711 }
 712
 713 static int machine_constraints_voltage(struct regulator_dev *rdev,
 714         struct regulation_constraints *constraints)
 715 {
 716         struct regulator_ops *ops = rdev->desc->ops;
 717         const char *name = rdev_get_name(rdev);
 718         int ret;
 719         unsigned selector;
 720
 721         /* do we need to apply the constraint voltage */
 722         if (rdev->constraints->apply_uV &&
 723                 rdev->constraints->min_uV == rdev->constraints->max_uV &&
 724                 ops->set_voltage) {
 725                 ret = ops->set_voltage(rdev,
 726                                        rdev->constraints->min_uV,
 727                                        rdev->constraints->max_uV,
 728                                        &selector);
 729                         if (ret < 0) {
 730                                 pr_err("failed to apply %duV constraint to %s\n",
 731                                         rdev->constraints->min_uV, name);
 732                                 rdev->constraints = NULL;
 733                                 return ret;
 734                         }
 735         }
 736
 737         /* constrain machine-level voltage specs to fit
 738          * the actual range supported by this regulator.
 739          */
 740         if (ops->list_voltage && rdev->desc->n_voltages) {
 741                 int     count = rdev->desc->n_voltages;
 742                 int     i;
 743                 int     min_uV = INT_MAX;
 744                 int     max_uV = INT_MIN;
 745                 int     cmin = constraints->min_uV;
 746                 int     cmax = constraints->max_uV;
 747
 748                 /* it's safe to autoconfigure fixed-voltage supplies
 749                    and the constraints are used by list_voltage. */
 750                 if (count == 1 && !cmin) {
 751                         cmin = 1;
 752                         cmax = INT_MAX;
 753                         constraints->min_uV = cmin;
 754                         constraints->max_uV = cmax;
 755                 }
 756
 757                 /* voltage constraints are optional */
 758                 if ((cmin == 0) && (cmax == 0))
 759                         return 0;
 760
 761                 /* else require explicit machine-level constraints */
 762                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 763                         pr_err("%s '%s' voltage constraints\n", "invalid",
 764                                 name);
 765                         return -EINVAL;
 766                 }
 767
 768                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 769                 for (i = 0; i < count; i++) {
 770                         int     value;
 771
 772                         value = ops->list_voltage(rdev, i);
 773                         if (value <= 0)
 774                                 continue;
 775
 776                         /* maybe adjust [min_uV..max_uV] */
 777                         if (value >= cmin && value < min_uV)
 778                                 min_uV = value;
 779                         if (value <= cmax && value > max_uV)
 780                                 max_uV = value;
 781                 }
 782
 783                 /* final: [min_uV..max_uV] valid iff constraints valid */
 784                 if (max_uV < min_uV) {
 785                         pr_err("%s '%s' voltage constraints\n", "unsupportable",
 786                                 name);
 787                         return -EINVAL;
 788                 }
 789
 790                 /* use regulator's subset of machine constraints */
 791                 if (constraints->min_uV < min_uV) {
 792                         pr_debug("override '%s' %s, %d -> %d\n",
 793                                  name, "min_uV",
 794                                  constraints->min_uV, min_uV);
 795                         constraints->min_uV = min_uV;
 796                 }
 797                 if (constraints->max_uV > max_uV) {
 798                         pr_debug("override '%s' %s, %d -> %d\n",
 799                                  name, "max_uV",
 800                                  constraints->max_uV, max_uV);
 801                         constraints->max_uV = max_uV;
 802                 }
 803         }
 804
 805         return 0;
 806 }
 807
 808 /**
 809  * set_machine_constraints - sets regulator constraints
 810  * @rdev: regulator source
 811  * @constraints: constraints to apply
 812  *
 813  * Allows platform initialisation code to define and constrain
 814  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 815  * Constraints *must* be set by platform code in order for some
 816  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 817  * set_mode.
 818  */
 819 static int set_machine_constraints(struct regulator_dev *rdev,
 820         struct regulation_constraints *constraints)
 821 {
 822         int ret = 0;
 823         const char *name;
 824         struct regulator_ops *ops = rdev->desc->ops;
 825
 826         rdev->constraints = constraints;
 827
 828         name = rdev_get_name(rdev);
 829
 830         ret = machine_constraints_voltage(rdev, constraints);
 831         if (ret != 0)
 832                 goto out;
 833
 834         /* do we need to setup our suspend state */
 835         if (constraints->initial_state) {
 836                 ret = suspend_prepare(rdev, constraints->initial_state);
 837                 if (ret < 0) {
 838                         pr_err("failed to set suspend state for %s\n",
 839                                 name);
 840                         rdev->constraints = NULL;
 841                         goto out;
 842                 }
 843         }
 844
 845         if (constraints->initial_mode) {
 846                 if (!ops->set_mode) {
 847                         pr_err("no set_mode operation for %s\n",
 848                                 name);
 849                         ret = -EINVAL;
 850                         goto out;
 851                 }
 852
 853                 ret = ops->set_mode(rdev, constraints->initial_mode);
 854                 if (ret < 0) {
 855                         pr_err("failed to set initial mode for %s: %d\n",
 856                                 name, ret);
 857                         goto out;
 858                 }
 859         }
 860
 861         /* If the constraints say the regulator should be on at this point
 862          * and we have control then make sure it is enabled.
 863          */
 864         if ((constraints->always_on || constraints->boot_on) && ops->enable) {
 865                 ret = ops->enable(rdev);
 866                 if (ret < 0) {
 867                         pr_err("failed to enable %s\n", name);
 868                         rdev->constraints = NULL;
 869                         goto out;
 870                 }
 871         }
 872
 873         print_constraints(rdev);
 874 out:
 875         return ret;
 876 }
 877
 878 /**
 879  * set_supply - set regulator supply regulator
 880  * @rdev: regulator name
 881  * @supply_rdev: supply regulator name
 882  *
 883  * Called by platform initialisation code to set the supply regulator for this
 884  * regulator. This ensures that a regulators supply will also be enabled by the
 885  * core if it's child is enabled.
 886  */
 887 static int set_supply(struct regulator_dev *rdev,
 888         struct regulator_dev *supply_rdev)
 889 {
 890         int err;
 891
 892         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
 893                                 "supply");
 894         if (err) {
 895                 pr_err("could not add device link %s err %d\n",
 896                         supply_rdev->dev.kobj.name, err);
 897                        goto out;
 898         }
 899         rdev->supply = supply_rdev;
 900         list_add(&rdev->slist, &supply_rdev->supply_list);
 901 out:
 902         return err;
 903 }
 904
 905 /**
 906  * set_consumer_device_supply - Bind a regulator to a symbolic supply
 907  * @rdev:         regulator source
 908  * @consumer_dev: device the supply applies to
 909  * @consumer_dev_name: dev_name() string for device supply applies to
 910  * @supply:       symbolic name for supply
 911  *
 912  * Allows platform initialisation code to map physical regulator
 913  * sources to symbolic names for supplies for use by devices.  Devices
 914  * should use these symbolic names to request regulators, avoiding the
 915  * need to provide board-specific regulator names as platform data.
 916  *
 917  * Only one of consumer_dev and consumer_dev_name may be specified.
 918  */
 919 static int set_consumer_device_supply(struct regulator_dev *rdev,
 920         struct device *consumer_dev, const char *consumer_dev_name,
 921         const char *supply)
 922 {
 923         struct regulator_map *node;
 924         int has_dev;
 925
 926         if (consumer_dev && consumer_dev_name)
 927                 return -EINVAL;
 928
 929         if (!consumer_dev_name && consumer_dev)
 930                 consumer_dev_name = dev_name(consumer_dev);
 931
 932         if (supply == NULL)
 933                 return -EINVAL;
 934
 935         if (consumer_dev_name != NULL)
 936                 has_dev = 1;
 937         else
 938                 has_dev = 0;
 939
 940         list_for_each_entry(node, &regulator_map_list, list) {
 941                 if (node->dev_name && consumer_dev_name) {
 942                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
 943                                 continue;
 944                 } else if (node->dev_name || consumer_dev_name) {
 945                         continue;
 946                 }
 947
 948                 if (strcmp(node->supply, supply) != 0)
 949                         continue;
 950
 951                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
 952                                 dev_name(&node->regulator->dev),
 953                                 node->regulator->desc->name,
 954                                 supply,
 955                                 dev_name(&rdev->dev), rdev_get_name(rdev));
 956                 return -EBUSY;
 957         }
 958
 959         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
 960         if (node == NULL)
 961                 return -ENOMEM;
 962
 963         node->regulator = rdev;
 964         node->supply = supply;
 965
 966         if (has_dev) {
 967                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
 968                 if (node->dev_name == NULL) {
 969                         kfree(node);
 970                         return -ENOMEM;
 971                 }
 972         }
 973
 974         list_add(&node->list, &regulator_map_list);
 975         return 0;
 976 }
 977
 978 static void unset_regulator_supplies(struct regulator_dev *rdev)
 979 {
 980         struct regulator_map *node, *n;
 981
 982         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
 983                 if (rdev == node->regulator) {
 984                         list_del(&node->list);
 985                         kfree(node->dev_name);
 986                         kfree(node);
 987                 }
 988         }
 989 }
 990
 991 #define REG_STR_SIZE    32
 992
 993 static struct regulator *create_regulator(struct regulator_dev *rdev,
 994                                           struct device *dev,
 995                                           const char *supply_name)
 996 {
 997         struct regulator *regulator;
 998         char buf[REG_STR_SIZE];
 999         int err, size;
1000
1001         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1002         if (regulator == NULL)
1003                 return NULL;
1004
1005         mutex_lock(&rdev->mutex);
1006         regulator->rdev = rdev;
1007         list_add(&regulator->list, &rdev->consumer_list);
1008
1009         if (dev) {
1010                 /* create a 'requested_microamps_name' sysfs entry */
1011                 size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
1012                         supply_name);
1013                 if (size >= REG_STR_SIZE)
1014                         goto overflow_err;
1015
1016                 regulator->dev = dev;
1017                 sysfs_attr_init(&regulator->dev_attr.attr);
1018                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1019                 if (regulator->dev_attr.attr.name == NULL)
1020                         goto attr_name_err;
1021
1022                 regulator->dev_attr.attr.mode = 0444;
1023                 regulator->dev_attr.show = device_requested_uA_show;
1024                 err = device_create_file(dev, &regulator->dev_attr);
1025                 if (err < 0) {
1026                         pr_warning("could not add regulator_dev"
1027                                 " requested microamps sysfs entry\n");
1028                         goto attr_name_err;
1029                 }
1030
1031                 /* also add a link to the device sysfs entry */
1032                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1033                                  dev->kobj.name, supply_name);
1034                 if (size >= REG_STR_SIZE)
1035                         goto attr_err;
1036
1037                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1038                 if (regulator->supply_name == NULL)
1039                         goto attr_err;
1040
1041                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1042                                         buf);
1043                 if (err) {
1044                         pr_warning("could not add device link %s err %d\n",
1045                                dev->kobj.name, err);
1046                         goto link_name_err;
1047                 }
1048         }
1049         mutex_unlock(&rdev->mutex);
1050         return regulator;
1051 link_name_err:
1052         kfree(regulator->supply_name);
1053 attr_err:
1054         device_remove_file(regulator->dev, &regulator->dev_attr);
1055 attr_name_err:
1056         kfree(regulator->dev_attr.attr.name);
1057 overflow_err:
1058         list_del(&regulator->list);
1059         kfree(regulator);
1060         mutex_unlock(&rdev->mutex);
1061         return NULL;
1062 }
1063
1064 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1065 {
1066         if (!rdev->desc->ops->enable_time)
1067                 return 0;
1068         return rdev->desc->ops->enable_time(rdev);
1069 }
1070
1071 /* Internal regulator request function */
1072 static struct regulator *_regulator_get(struct device *dev, const char *id,
1073                                         int exclusive)
1074 {
1075         struct regulator_dev *rdev;
1076         struct regulator_map *map;
1077         struct regulator *regulator = ERR_PTR(-ENODEV);
1078         const char *devname = NULL;
1079         int ret;
1080
1081         if (id == NULL) {
1082                 pr_err("regulator: get() with no identifier\n");
1083                 return regulator;
1084         }
1085
1086         if (dev)
1087                 devname = dev_name(dev);
1088
1089         mutex_lock(&regulator_list_mutex);
1090
1091         list_for_each_entry(map, &regulator_map_list, list) {
1092                 /* If the mapping has a device set up it must match */
1093                 if (map->dev_name &&
1094                     (!devname || strcmp(map->dev_name, devname)))
1095                         continue;
1096
1097                 if (strcmp(map->supply, id) == 0) {
1098                         rdev = map->regulator;
1099                         goto found;
1100                 }
1101         }
1102
1103         if (board_wants_dummy_regulator) {
1104                 rdev = dummy_regulator_rdev;
1105                 goto found;
1106         }
1107
1108 #ifdef CONFIG_REGULATOR_DUMMY
1109         if (!devname)
1110                 devname = "deviceless";
1111
1112         /* If the board didn't flag that it was fully constrained then
1113          * substitute in a dummy regulator so consumers can continue.
1114          */
1115         if (!has_full_constraints) {
1116                 pr_warning("%s supply %s not found, using dummy regulator\n",
1117                            devname, id);
1118                 rdev = dummy_regulator_rdev;
1119                 goto found;
1120         }
1121 #endif
1122
1123         mutex_unlock(&regulator_list_mutex);
1124         return regulator;
1125
1126 found:
1127         if (rdev->exclusive) {
1128                 regulator = ERR_PTR(-EPERM);
1129                 goto out;
1130         }
1131
1132         if (exclusive && rdev->open_count) {
1133                 regulator = ERR_PTR(-EBUSY);
1134                 goto out;
1135         }
1136
1137         if (!try_module_get(rdev->owner))
1138                 goto out;
1139
1140         regulator = create_regulator(rdev, dev, id);
1141         if (regulator == NULL) {
1142                 regulator = ERR_PTR(-ENOMEM);
1143                 module_put(rdev->owner);
1144         }
1145
1146         rdev->open_count++;
1147         if (exclusive) {
1148                 rdev->exclusive = 1;
1149
1150                 ret = _regulator_is_enabled(rdev);
1151                 if (ret > 0)
1152                         rdev->use_count = 1;
1153                 else
1154                         rdev->use_count = 0;
1155         }
1156
1157 out:
1158         mutex_unlock(&regulator_list_mutex);
1159
1160         return regulator;
1161 }
1162
1163 /**
1164  * regulator_get - lookup and obtain a reference to a regulator.
1165  * @dev: device for regulator "consumer"
1166  * @id: Supply name or regulator ID.
1167  *
1168  * Returns a struct regulator corresponding to the regulator producer,
1169  * or IS_ERR() condition containing errno.
1170  *
1171  * Use of supply names configured via regulator_set_device_supply() is
1172  * strongly encouraged.  It is recommended that the supply name used
1173  * should match the name used for the supply and/or the relevant
1174  * device pins in the datasheet.
1175  */
1176 struct regulator *regulator_get(struct device *dev, const char *id)
1177 {
1178         return _regulator_get(dev, id, 0);
1179 }
1180 EXPORT_SYMBOL_GPL(regulator_get);
1181
1182 /**
1183  * regulator_get_exclusive - obtain exclusive access to a regulator.
1184  * @dev: device for regulator "consumer"
1185  * @id: Supply name or regulator ID.
1186  *
1187  * Returns a struct regulator corresponding to the regulator producer,
1188  * or IS_ERR() condition containing errno.  Other consumers will be
1189  * unable to obtain this reference is held and the use count for the
1190  * regulator will be initialised to reflect the current state of the
1191  * regulator.
1192  *
1193  * This is intended for use by consumers which cannot tolerate shared
1194  * use of the regulator such as those which need to force the
1195  * regulator off for correct operation of the hardware they are
1196  * controlling.
1197  *
1198  * Use of supply names configured via regulator_set_device_supply() is
1199  * strongly encouraged.  It is recommended that the supply name used
1200  * should match the name used for the supply and/or the relevant
1201  * device pins in the datasheet.
1202  */
1203 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1204 {
1205         return _regulator_get(dev, id, 1);
1206 }
1207 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1208
1209 /**
1210  * regulator_put - "free" the regulator source
1211  * @regulator: regulator source
1212  *
1213  * Note: drivers must ensure that all regulator_enable calls made on this
1214  * regulator source are balanced by regulator_disable calls prior to calling
1215  * this function.
1216  */
1217 void regulator_put(struct regulator *regulator)
1218 {
1219         struct regulator_dev *rdev;
1220
1221         if (regulator == NULL || IS_ERR(regulator))
1222                 return;
1223
1224         mutex_lock(&regulator_list_mutex);
1225         rdev = regulator->rdev;
1226
1227         /* remove any sysfs entries */
1228         if (regulator->dev) {
1229                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1230                 kfree(regulator->supply_name);
1231                 device_remove_file(regulator->dev, &regulator->dev_attr);
1232                 kfree(regulator->dev_attr.attr.name);
1233         }
1234         list_del(&regulator->list);
1235         kfree(regulator);
1236
1237         rdev->open_count--;
1238         rdev->exclusive = 0;
1239
1240         module_put(rdev->owner);
1241         mutex_unlock(&regulator_list_mutex);
1242 }
1243 EXPORT_SYMBOL_GPL(regulator_put);
1244
1245 static int _regulator_can_change_status(struct regulator_dev *rdev)
1246 {
1247         if (!rdev->constraints)
1248                 return 0;
1249
1250         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1251                 return 1;
1252         else
1253                 return 0;
1254 }
1255
1256 /* locks held by regulator_enable() */
1257 static int _regulator_enable(struct regulator_dev *rdev)
1258 {
1259         int ret, delay;
1260
1261         if (rdev->use_count == 0) {
1262                 /* do we need to enable the supply regulator first */
1263                 if (rdev->supply) {
1264                         mutex_lock(&rdev->supply->mutex);
1265                         ret = _regulator_enable(rdev->supply);
1266                         mutex_unlock(&rdev->supply->mutex);
1267                         if (ret < 0) {
1268                                 pr_err("failed to enable %s: %d\n",
1269                                        rdev_get_name(rdev), ret);
1270                                 return ret;
1271                         }
1272                 }
1273         }
1274
1275         /* check voltage and requested load before enabling */
1276         if (rdev->constraints &&
1277             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1278                 drms_uA_update(rdev);
1279
1280         if (rdev->use_count == 0) {
1281                 /* The regulator may on if it's not switchable or left on */
1282                 ret = _regulator_is_enabled(rdev);
1283                 if (ret == -EINVAL || ret == 0) {
1284                         if (!_regulator_can_change_status(rdev))
1285                                 return -EPERM;
1286
1287                         if (!rdev->desc->ops->enable)
1288                                 return -EINVAL;
1289
1290                         /* Query before enabling in case configuration
1291                          * dependant.  */
1292                         ret = _regulator_get_enable_time(rdev);
1293                         if (ret >= 0) {
1294                                 delay = ret;
1295                         } else {
1296                                 pr_warning("enable_time() failed for %s: %d\n",
1297                                            rdev_get_name(rdev),
1298                                            ret);
1299                                 delay = 0;
1300                         }
1301
1302                         trace_regulator_enable(rdev_get_name(rdev));
1303
1304                         /* Allow the regulator to ramp; it would be useful
1305                          * to extend this for bulk operations so that the
1306                          * regulators can ramp together.  */
1307                         ret = rdev->desc->ops->enable(rdev);
1308                         if (ret < 0)
1309                                 return ret;
1310
1311                         trace_regulator_enable_delay(rdev_get_name(rdev));
1312
1313                         if (delay >= 1000) {
1314                                 mdelay(delay / 1000);
1315                                 udelay(delay % 1000);
1316                         } else if (delay) {
1317                                 udelay(delay);
1318                         }
1319
1320                         trace_regulator_enable_complete(rdev_get_name(rdev));
1321
1322                 } else if (ret < 0) {
1323                         pr_err("is_enabled() failed for %s: %d\n",
1324                                 rdev_get_name(rdev), ret);
1325                         return ret;
1326                 }
1327                 /* Fallthrough on positive return values - already enabled */
1328         }
1329
1330         rdev->use_count++;
1331
1332         return 0;
1333 }
1334
1335 /**
1336  * regulator_enable - enable regulator output
1337  * @regulator: regulator source
1338  *
1339  * Request that the regulator be enabled with the regulator output at
1340  * the predefined voltage or current value.  Calls to regulator_enable()
1341  * must be balanced with calls to regulator_disable().
1342  *
1343  * NOTE: the output value can be set by other drivers, boot loader or may be
1344  * hardwired in the regulator.
1345  */
1346 int regulator_enable(struct regulator *regulator)
1347 {
1348         struct regulator_dev *rdev = regulator->rdev;
1349         int ret = 0;
1350
1351         mutex_lock(&rdev->mutex);
1352         ret = _regulator_enable(rdev);
1353         mutex_unlock(&rdev->mutex);
1354         return ret;
1355 }
1356 EXPORT_SYMBOL_GPL(regulator_enable);
1357
1358 /* locks held by regulator_disable() */
1359 static int _regulator_disable(struct regulator_dev *rdev,
1360                 struct regulator_dev **supply_rdev_ptr)
1361 {
1362         int ret = 0;
1363         *supply_rdev_ptr = NULL;
1364
1365         if (WARN(rdev->use_count <= 0,
1366                         "unbalanced disables for %s\n",
1367                         rdev_get_name(rdev)))
1368                 return -EIO;
1369
1370         /* are we the last user and permitted to disable ? */
1371         if (rdev->use_count == 1 &&
1372             (rdev->constraints && !rdev->constraints->always_on)) {
1373
1374                 /* we are last user */
1375                 if (_regulator_can_change_status(rdev) &&
1376                     rdev->desc->ops->disable) {
1377                         trace_regulator_disable(rdev_get_name(rdev));
1378
1379                         ret = rdev->desc->ops->disable(rdev);
1380                         if (ret < 0) {
1381                                 pr_err("failed to disable %s\n",
1382                                         rdev_get_name(rdev));
1383                                 return ret;
1384                         }
1385
1386                         trace_regulator_disable_complete(rdev_get_name(rdev));
1387
1388                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1389                                              NULL);
1390                 }
1391
1392                 /* decrease our supplies ref count and disable if required */
1393                 *supply_rdev_ptr = rdev->supply;
1394
1395                 rdev->use_count = 0;
1396         } else if (rdev->use_count > 1) {
1397
1398                 if (rdev->constraints &&
1399                         (rdev->constraints->valid_ops_mask &
1400                         REGULATOR_CHANGE_DRMS))
1401                         drms_uA_update(rdev);
1402
1403                 rdev->use_count--;
1404         }
1405         return ret;
1406 }
1407
1408 /**
1409  * regulator_disable - disable regulator output
1410  * @regulator: regulator source
1411  *
1412  * Disable the regulator output voltage or current.  Calls to
1413  * regulator_enable() must be balanced with calls to
1414  * regulator_disable().
1415  *
1416  * NOTE: this will only disable the regulator output if no other consumer
1417  * devices have it enabled, the regulator device supports disabling and
1418  * machine constraints permit this operation.
1419  */
1420 int regulator_disable(struct regulator *regulator)
1421 {
1422         struct regulator_dev *rdev = regulator->rdev;
1423         struct regulator_dev *supply_rdev = NULL;
1424         int ret = 0;
1425
1426         mutex_lock(&rdev->mutex);
1427         ret = _regulator_disable(rdev, &supply_rdev);
1428         mutex_unlock(&rdev->mutex);
1429
1430         /* decrease our supplies ref count and disable if required */
1431         while (supply_rdev != NULL) {
1432                 rdev = supply_rdev;
1433
1434                 mutex_lock(&rdev->mutex);
1435                 _regulator_disable(rdev, &supply_rdev);
1436                 mutex_unlock(&rdev->mutex);
1437         }
1438
1439         return ret;
1440 }
1441 EXPORT_SYMBOL_GPL(regulator_disable);
1442
1443 /* locks held by regulator_force_disable() */
1444 static int _regulator_force_disable(struct regulator_dev *rdev,
1445                 struct regulator_dev **supply_rdev_ptr)
1446 {
1447         int ret = 0;
1448
1449         /* force disable */
1450         if (rdev->desc->ops->disable) {
1451                 /* ah well, who wants to live forever... */
1452                 ret = rdev->desc->ops->disable(rdev);
1453                 if (ret < 0) {
1454                         pr_err("failed to force disable %s\n",
1455                                 rdev_get_name(rdev));
1456                         return ret;
1457                 }
1458                 /* notify other consumers that power has been forced off */
1459                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1460                         REGULATOR_EVENT_DISABLE, NULL);
1461         }
1462
1463         /* decrease our supplies ref count and disable if required */
1464         *supply_rdev_ptr = rdev->supply;
1465
1466         rdev->use_count = 0;
1467         return ret;
1468 }
1469
1470 /**
1471  * regulator_force_disable - force disable regulator output
1472  * @regulator: regulator source
1473  *
1474  * Forcibly disable the regulator output voltage or current.
1475  * NOTE: this *will* disable the regulator output even if other consumer
1476  * devices have it enabled. This should be used for situations when device
1477  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1478  */
1479 int regulator_force_disable(struct regulator *regulator)
1480 {
1481         struct regulator_dev *supply_rdev = NULL;
1482         int ret;
1483
1484         mutex_lock(&regulator->rdev->mutex);
1485         regulator->uA_load = 0;
1486         ret = _regulator_force_disable(regulator->rdev, &supply_rdev);
1487         mutex_unlock(&regulator->rdev->mutex);
1488
1489         if (supply_rdev)
1490                 regulator_disable(get_device_regulator(rdev_get_dev(supply_rdev)));
1491
1492         return ret;
1493 }
1494 EXPORT_SYMBOL_GPL(regulator_force_disable);
1495
1496 static int _regulator_is_enabled(struct regulator_dev *rdev)
1497 {
1498         /* If we don't know then assume that the regulator is always on */
1499         if (!rdev->desc->ops->is_enabled)
1500                 return 1;
1501
1502         return rdev->desc->ops->is_enabled(rdev);
1503 }
1504
1505 /**
1506  * regulator_is_enabled - is the regulator output enabled
1507  * @regulator: regulator source
1508  *
1509  * Returns positive if the regulator driver backing the source/client
1510  * has requested that the device be enabled, zero if it hasn't, else a
1511  * negative errno code.
1512  *
1513  * Note that the device backing this regulator handle can have multiple
1514  * users, so it might be enabled even if regulator_enable() was never
1515  * called for this particular source.
1516  */
1517 int regulator_is_enabled(struct regulator *regulator)
1518 {
1519         int ret;
1520
1521         mutex_lock(&regulator->rdev->mutex);
1522         ret = _regulator_is_enabled(regulator->rdev);
1523         mutex_unlock(&regulator->rdev->mutex);
1524
1525         return ret;
1526 }
1527 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1528
1529 /**
1530  * regulator_count_voltages - count regulator_list_voltage() selectors
1531  * @regulator: regulator source
1532  *
1533  * Returns number of selectors, or negative errno.  Selectors are
1534  * numbered starting at zero, and typically correspond to bitfields
1535  * in hardware registers.
1536  */
1537 int regulator_count_voltages(struct regulator *regulator)
1538 {
1539         struct regulator_dev    *rdev = regulator->rdev;
1540
1541         return rdev->desc->n_voltages ? : -EINVAL;
1542 }
1543 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1544
1545 /**
1546  * regulator_list_voltage - enumerate supported voltages
1547  * @regulator: regulator source
1548  * @selector: identify voltage to list
1549  * Context: can sleep
1550  *
1551  * Returns a voltage that can be passed to @regulator_set_voltage(),
1552  * zero if this selector code can't be used on this system, or a
1553  * negative errno.
1554  */
1555 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1556 {
1557         struct regulator_dev    *rdev = regulator->rdev;
1558         struct regulator_ops    *ops = rdev->desc->ops;
1559         int                     ret;
1560
1561         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1562                 return -EINVAL;
1563
1564         mutex_lock(&rdev->mutex);
1565         ret = ops->list_voltage(rdev, selector);
1566         mutex_unlock(&rdev->mutex);
1567
1568         if (ret > 0) {
1569                 if (ret < rdev->constraints->min_uV)
1570                         ret = 0;
1571                 else if (ret > rdev->constraints->max_uV)
1572                         ret = 0;
1573         }
1574
1575         return ret;
1576 }
1577 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1578
1579 /**
1580  * regulator_is_supported_voltage - check if a voltage range can be supported
1581  *
1582  * @regulator: Regulator to check.
1583  * @min_uV: Minimum required voltage in uV.
1584  * @max_uV: Maximum required voltage in uV.
1585  *
1586  * Returns a boolean or a negative error code.
1587  */
1588 int regulator_is_supported_voltage(struct regulator *regulator,
1589                                    int min_uV, int max_uV)
1590 {
1591         int i, voltages, ret;
1592
1593         ret = regulator_count_voltages(regulator);
1594         if (ret < 0)
1595                 return ret;
1596         voltages = ret;
1597
1598         for (i = 0; i < voltages; i++) {
1599                 ret = regulator_list_voltage(regulator, i);
1600
1601                 if (ret >= min_uV && ret <= max_uV)
1602                         return 1;
1603         }
1604
1605         return 0;
1606 }
1607
1608 /**
1609  * regulator_set_voltage - set regulator output voltage
1610  * @regulator: regulator source
1611  * @min_uV: Minimum required voltage in uV
1612  * @max_uV: Maximum acceptable voltage in uV
1613  *
1614  * Sets a voltage regulator to the desired output voltage. This can be set
1615  * during any regulator state. IOW, regulator can be disabled or enabled.
1616  *
1617  * If the regulator is enabled then the voltage will change to the new value
1618  * immediately otherwise if the regulator is disabled the regulator will
1619  * output at the new voltage when enabled.
1620  *
1621  * NOTE: If the regulator is shared between several devices then the lowest
1622  * request voltage that meets the system constraints will be used.
1623  * Regulator system constraints must be set for this regulator before
1624  * calling this function otherwise this call will fail.
1625  */
1626 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1627 {
1628         struct regulator_dev *rdev = regulator->rdev;
1629         int ret;
1630         unsigned selector;
1631
1632         mutex_lock(&rdev->mutex);
1633
1634         /* sanity check */
1635         if (!rdev->desc->ops->set_voltage) {
1636                 ret = -EINVAL;
1637                 goto out;
1638         }
1639
1640         /* constraints check */
1641         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1642         if (ret < 0)
1643                 goto out;
1644         regulator->min_uV = min_uV;
1645         regulator->max_uV = max_uV;
1646
1647         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
1648
1649         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, &selector);
1650
1651         if (rdev->desc->ops->list_voltage)
1652                 selector = rdev->desc->ops->list_voltage(rdev, selector);
1653         else
1654                 selector = -1;
1655
1656         trace_regulator_set_voltage_complete(rdev_get_name(rdev), selector);
1657
1658 out:
1659         _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1660         mutex_unlock(&rdev->mutex);
1661         return ret;
1662 }
1663 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1664
1665 static int _regulator_get_voltage(struct regulator_dev *rdev)
1666 {
1667         /* sanity check */
1668         if (rdev->desc->ops->get_voltage)
1669                 return rdev->desc->ops->get_voltage(rdev);
1670         else
1671                 return -EINVAL;
1672 }
1673
1674 /**
1675  * regulator_get_voltage - get regulator output voltage
1676  * @regulator: regulator source
1677  *
1678  * This returns the current regulator voltage in uV.
1679  *
1680  * NOTE: If the regulator is disabled it will return the voltage value. This
1681  * function should not be used to determine regulator state.
1682  */
1683 int regulator_get_voltage(struct regulator *regulator)
1684 {
1685         int ret;
1686
1687         mutex_lock(&regulator->rdev->mutex);
1688
1689         ret = _regulator_get_voltage(regulator->rdev);
1690
1691         mutex_unlock(&regulator->rdev->mutex);
1692
1693         return ret;
1694 }
1695 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1696
1697 /**
1698  * regulator_set_current_limit - set regulator output current limit
1699  * @regulator: regulator source
1700  * @min_uA: Minimuum supported current in uA
1701  * @max_uA: Maximum supported current in uA
1702  *
1703  * Sets current sink to the desired output current. This can be set during
1704  * any regulator state. IOW, regulator can be disabled or enabled.
1705  *
1706  * If the regulator is enabled then the current will change to the new value
1707  * immediately otherwise if the regulator is disabled the regulator will
1708  * output at the new current when enabled.
1709  *
1710  * NOTE: Regulator system constraints must be set for this regulator before
1711  * calling this function otherwise this call will fail.
1712  */
1713 int regulator_set_current_limit(struct regulator *regulator,
1714                                int min_uA, int max_uA)
1715 {
1716         struct regulator_dev *rdev = regulator->rdev;
1717         int ret;
1718
1719         mutex_lock(&rdev->mutex);
1720
1721         /* sanity check */
1722         if (!rdev->desc->ops->set_current_limit) {
1723                 ret = -EINVAL;
1724                 goto out;
1725         }
1726
1727         /* constraints check */
1728         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1729         if (ret < 0)
1730                 goto out;
1731
1732         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1733 out:
1734         mutex_unlock(&rdev->mutex);
1735         return ret;
1736 }
1737 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1738
1739 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1740 {
1741         int ret;
1742
1743         mutex_lock(&rdev->mutex);
1744
1745         /* sanity check */
1746         if (!rdev->desc->ops->get_current_limit) {
1747                 ret = -EINVAL;
1748                 goto out;
1749         }
1750
1751         ret = rdev->desc->ops->get_current_limit(rdev);
1752 out:
1753         mutex_unlock(&rdev->mutex);
1754         return ret;
1755 }
1756
1757 /**
1758  * regulator_get_current_limit - get regulator output current
1759  * @regulator: regulator source
1760  *
1761  * This returns the current supplied by the specified current sink in uA.
1762  *
1763  * NOTE: If the regulator is disabled it will return the current value. This
1764  * function should not be used to determine regulator state.
1765  */
1766 int regulator_get_current_limit(struct regulator *regulator)
1767 {
1768         return _regulator_get_current_limit(regulator->rdev);
1769 }
1770 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1771
1772 /**
1773  * regulator_set_mode - set regulator operating mode
1774  * @regulator: regulator source
1775  * @mode: operating mode - one of the REGULATOR_MODE constants
1776  *
1777  * Set regulator operating mode to increase regulator efficiency or improve
1778  * regulation performance.
1779  *
1780  * NOTE: Regulator system constraints must be set for this regulator before
1781  * calling this function otherwise this call will fail.
1782  */
1783 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1784 {
1785         struct regulator_dev *rdev = regulator->rdev;
1786         int ret;
1787         int regulator_curr_mode;
1788
1789         mutex_lock(&rdev->mutex);
1790
1791         /* sanity check */
1792         if (!rdev->desc->ops->set_mode) {
1793                 ret = -EINVAL;
1794                 goto out;
1795         }
1796
1797         /* return if the same mode is requested */
1798         if (rdev->desc->ops->get_mode) {
1799                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
1800                 if (regulator_curr_mode == mode) {
1801                         ret = 0;
1802                         goto out;
1803                 }
1804         }
1805
1806         /* constraints check */
1807         ret = regulator_check_mode(rdev, mode);
1808         if (ret < 0)
1809                 goto out;
1810
1811         ret = rdev->desc->ops->set_mode(rdev, mode);
1812 out:
1813         mutex_unlock(&rdev->mutex);
1814         return ret;
1815 }
1816 EXPORT_SYMBOL_GPL(regulator_set_mode);
1817
1818 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1819 {
1820         int ret;
1821
1822         mutex_lock(&rdev->mutex);
1823
1824         /* sanity check */
1825         if (!rdev->desc->ops->get_mode) {
1826                 ret = -EINVAL;
1827                 goto out;
1828         }
1829
1830         ret = rdev->desc->ops->get_mode(rdev);
1831 out:
1832         mutex_unlock(&rdev->mutex);
1833         return ret;
1834 }
1835
1836 /**
1837  * regulator_get_mode - get regulator operating mode
1838  * @regulator: regulator source
1839  *
1840  * Get the current regulator operating mode.
1841  */
1842 unsigned int regulator_get_mode(struct regulator *regulator)
1843 {
1844         return _regulator_get_mode(regulator->rdev);
1845 }
1846 EXPORT_SYMBOL_GPL(regulator_get_mode);
1847
1848 /**
1849  * regulator_set_optimum_mode - set regulator optimum operating mode
1850  * @regulator: regulator source
1851  * @uA_load: load current
1852  *
1853  * Notifies the regulator core of a new device load. This is then used by
1854  * DRMS (if enabled by constraints) to set the most efficient regulator
1855  * operating mode for the new regulator loading.
1856  *
1857  * Consumer devices notify their supply regulator of the maximum power
1858  * they will require (can be taken from device datasheet in the power
1859  * consumption tables) when they change operational status and hence power
1860  * state. Examples of operational state changes that can affect power
1861  * consumption are :-
1862  *
1863  *    o Device is opened / closed.
1864  *    o Device I/O is about to begin or has just finished.
1865  *    o Device is idling in between work.
1866  *
1867  * This information is also exported via sysfs to userspace.
1868  *
1869  * DRMS will sum the total requested load on the regulator and change
1870  * to the most efficient operating mode if platform constraints allow.
1871  *
1872  * Returns the new regulator mode or error.
1873  */
1874 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1875 {
1876         struct regulator_dev *rdev = regulator->rdev;
1877         struct regulator *consumer;
1878         int ret, output_uV, input_uV, total_uA_load = 0;
1879         unsigned int mode;
1880
1881         mutex_lock(&rdev->mutex);
1882
1883         regulator->uA_load = uA_load;
1884         ret = regulator_check_drms(rdev);
1885         if (ret < 0)
1886                 goto out;
1887         ret = -EINVAL;
1888
1889         /* sanity check */
1890         if (!rdev->desc->ops->get_optimum_mode)
1891                 goto out;
1892
1893         /* get output voltage */
1894         output_uV = rdev->desc->ops->get_voltage(rdev);
1895         if (output_uV <= 0) {
1896                 pr_err("invalid output voltage found for %s\n",
1897                         rdev_get_name(rdev));
1898                 goto out;
1899         }
1900
1901         /* get input voltage */
1902         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1903                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1904         else
1905                 input_uV = rdev->constraints->input_uV;
1906         if (input_uV <= 0) {
1907                 pr_err("invalid input voltage found for %s\n",
1908                         rdev_get_name(rdev));
1909                 goto out;
1910         }
1911
1912         /* calc total requested load for this regulator */
1913         list_for_each_entry(consumer, &rdev->consumer_list, list)
1914                 total_uA_load += consumer->uA_load;
1915
1916         mode = rdev->desc->ops->get_optimum_mode(rdev,
1917                                                  input_uV, output_uV,
1918                                                  total_uA_load);
1919         ret = regulator_check_mode(rdev, mode);
1920         if (ret < 0) {
1921                 pr_err("failed to get optimum mode for %s @"
1922                         " %d uA %d -> %d uV\n",  rdev_get_name(rdev),
1923                         total_uA_load, input_uV, output_uV);
1924                 goto out;
1925         }
1926
1927         ret = rdev->desc->ops->set_mode(rdev, mode);
1928         if (ret < 0) {
1929                 pr_err("failed to set optimum mode %x for %s\n",
1930                          mode, rdev_get_name(rdev));
1931                 goto out;
1932         }
1933         ret = mode;
1934 out:
1935         mutex_unlock(&rdev->mutex);
1936         return ret;
1937 }
1938 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1939
1940 /**
1941  * regulator_register_notifier - register regulator event notifier
1942  * @regulator: regulator source
1943  * @nb: notifier block
1944  *
1945  * Register notifier block to receive regulator events.
1946  */
1947 int regulator_register_notifier(struct regulator *regulator,
1948                               struct notifier_block *nb)
1949 {
1950         return blocking_notifier_chain_register(&regulator->rdev->notifier,
1951                                                 nb);
1952 }
1953 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1954
1955 /**
1956  * regulator_unregister_notifier - unregister regulator event notifier
1957  * @regulator: regulator source
1958  * @nb: notifier block
1959  *
1960  * Unregister regulator event notifier block.
1961  */
1962 int regulator_unregister_notifier(struct regulator *regulator,
1963                                 struct notifier_block *nb)
1964 {
1965         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1966                                                   nb);
1967 }
1968 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1969
1970 /* notify regulator consumers and downstream regulator consumers.
1971  * Note mutex must be held by caller.
1972  */
1973 static void _notifier_call_chain(struct regulator_dev *rdev,
1974                                   unsigned long event, void *data)
1975 {
1976         struct regulator_dev *_rdev;
1977
1978         /* call rdev chain first */
1979         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1980
1981         /* now notify regulator we supply */
1982         list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1983                 mutex_lock(&_rdev->mutex);
1984                 _notifier_call_chain(_rdev, event, data);
1985                 mutex_unlock(&_rdev->mutex);
1986         }
1987 }
1988
1989 /**
1990  * regulator_bulk_get - get multiple regulator consumers
1991  *
1992  * @dev:           Device to supply
1993  * @num_consumers: Number of consumers to register
1994  * @consumers:     Configuration of consumers; clients are stored here.
1995  *
1996  * @return 0 on success, an errno on failure.
1997  *
1998  * This helper function allows drivers to get several regulator
1999  * consumers in one operation.  If any of the regulators cannot be
2000  * acquired then any regulators that were allocated will be freed
2001  * before returning to the caller.
2002  */
2003 int regulator_bulk_get(struct device *dev, int num_consumers,
2004                        struct regulator_bulk_data *consumers)
2005 {
2006         int i;
2007         int ret;
2008
2009         for (i = 0; i < num_consumers; i++)
2010                 consumers[i].consumer = NULL;
2011
2012         for (i = 0; i < num_consumers; i++) {
2013                 consumers[i].consumer = regulator_get(dev,
2014                                                       consumers[i].supply);
2015                 if (IS_ERR(consumers[i].consumer)) {
2016                         ret = PTR_ERR(consumers[i].consumer);
2017                         dev_err(dev, "Failed to get supply '%s': %d\n",
2018                                 consumers[i].supply, ret);
2019                         consumers[i].consumer = NULL;
2020                         goto err;
2021                 }
2022         }
2023
2024         return 0;
2025
2026 err:
2027         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
2028                 regulator_put(consumers[i].consumer);
2029
2030         return ret;
2031 }
2032 EXPORT_SYMBOL_GPL(regulator_bulk_get);
2033
2034 /**
2035  * regulator_bulk_enable - enable multiple regulator consumers
2036  *
2037  * @num_consumers: Number of consumers
2038  * @consumers:     Consumer data; clients are stored here.
2039  * @return         0 on success, an errno on failure
2040  *
2041  * This convenience API allows consumers to enable multiple regulator
2042  * clients in a single API call.  If any consumers cannot be enabled
2043  * then any others that were enabled will be disabled again prior to
2044  * return.
2045  */
2046 int regulator_bulk_enable(int num_consumers,
2047                           struct regulator_bulk_data *consumers)
2048 {
2049         int i;
2050         int ret;
2051
2052         for (i = 0; i < num_consumers; i++) {
2053                 ret = regulator_enable(consumers[i].consumer);
2054                 if (ret != 0)
2055                         goto err;
2056         }
2057
2058         return 0;
2059
2060 err:
2061         printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
2062         for (--i; i >= 0; --i)
2063                 regulator_disable(consumers[i].consumer);
2064
2065         return ret;
2066 }
2067 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2068
2069 /**
2070  * regulator_bulk_disable - disable multiple regulator consumers
2071  *
2072  * @num_consumers: Number of consumers
2073  * @consumers:     Consumer data; clients are stored here.
2074  * @return         0 on success, an errno on failure
2075  *
2076  * This convenience API allows consumers to disable multiple regulator
2077  * clients in a single API call.  If any consumers cannot be enabled
2078  * then any others that were disabled will be disabled again prior to
2079  * return.
2080  */
2081 int regulator_bulk_disable(int num_consumers,
2082                            struct regulator_bulk_data *consumers)
2083 {
2084         int i;
2085         int ret;
2086
2087         for (i = 0; i < num_consumers; i++) {
2088                 ret = regulator_disable(consumers[i].consumer);
2089                 if (ret != 0)
2090                         goto err;
2091         }
2092
2093         return 0;
2094
2095 err:
2096         printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
2097                ret);
2098         for (--i; i >= 0; --i)
2099                 regulator_enable(consumers[i].consumer);
2100
2101         return ret;
2102 }
2103 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2104
2105 /**
2106  * regulator_bulk_free - free multiple regulator consumers
2107  *
2108  * @num_consumers: Number of consumers
2109  * @consumers:     Consumer data; clients are stored here.
2110  *
2111  * This convenience API allows consumers to free multiple regulator
2112  * clients in a single API call.
2113  */
2114 void regulator_bulk_free(int num_consumers,
2115                          struct regulator_bulk_data *consumers)
2116 {
2117         int i;
2118
2119         for (i = 0; i < num_consumers; i++) {
2120                 regulator_put(consumers[i].consumer);
2121                 consumers[i].consumer = NULL;
2122         }
2123 }
2124 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2125
2126 /**
2127  * regulator_notifier_call_chain - call regulator event notifier
2128  * @rdev: regulator source
2129  * @event: notifier block
2130  * @data: callback-specific data.
2131  *
2132  * Called by regulator drivers to notify clients a regulator event has
2133  * occurred. We also notify regulator clients downstream.
2134  * Note lock must be held by caller.
2135  */
2136 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2137                                   unsigned long event, void *data)
2138 {
2139         _notifier_call_chain(rdev, event, data);
2140         return NOTIFY_DONE;
2141
2142 }
2143 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2144
2145 /**
2146  * regulator_mode_to_status - convert a regulator mode into a status
2147  *
2148  * @mode: Mode to convert
2149  *
2150  * Convert a regulator mode into a status.
2151  */
2152 int regulator_mode_to_status(unsigned int mode)
2153 {
2154         switch (mode) {
2155         case REGULATOR_MODE_FAST:
2156                 return REGULATOR_STATUS_FAST;
2157         case REGULATOR_MODE_NORMAL:
2158                 return REGULATOR_STATUS_NORMAL;
2159         case REGULATOR_MODE_IDLE:
2160                 return REGULATOR_STATUS_IDLE;
2161         case REGULATOR_STATUS_STANDBY:
2162                 return REGULATOR_STATUS_STANDBY;
2163         default:
2164                 return 0;
2165         }
2166 }
2167 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2168
2169 /*
2170  * To avoid cluttering sysfs (and memory) with useless state, only
2171  * create attributes that can be meaningfully displayed.
2172  */
2173 static int add_regulator_attributes(struct regulator_dev *rdev)
2174 {
2175         struct device           *dev = &rdev->dev;
2176         struct regulator_ops    *ops = rdev->desc->ops;
2177         int                     status = 0;
2178
2179         /* some attributes need specific methods to be displayed */
2180         if (ops->get_voltage) {
2181                 status = device_create_file(dev, &dev_attr_microvolts);
2182                 if (status < 0)
2183                         return status;
2184         }
2185         if (ops->get_current_limit) {
2186                 status = device_create_file(dev, &dev_attr_microamps);
2187                 if (status < 0)
2188                         return status;
2189         }
2190         if (ops->get_mode) {
2191                 status = device_create_file(dev, &dev_attr_opmode);
2192                 if (status < 0)
2193                         return status;
2194         }
2195         if (ops->is_enabled) {
2196                 status = device_create_file(dev, &dev_attr_state);
2197                 if (status < 0)
2198                         return status;
2199         }
2200         if (ops->get_status) {
2201                 status = device_create_file(dev, &dev_attr_status);
2202                 if (status < 0)
2203                         return status;
2204         }
2205
2206         /* some attributes are type-specific */
2207         if (rdev->desc->type == REGULATOR_CURRENT) {
2208                 status = device_create_file(dev, &dev_attr_requested_microamps);
2209                 if (status < 0)
2210                         return status;
2211         }
2212
2213         /* all the other attributes exist to support constraints;
2214          * don't show them if there are no constraints, or if the
2215          * relevant supporting methods are missing.
2216          */
2217         if (!rdev->constraints)
2218                 return status;
2219
2220         /* constraints need specific supporting methods */
2221         if (ops->set_voltage) {
2222                 status = device_create_file(dev, &dev_attr_min_microvolts);
2223                 if (status < 0)
2224                         return status;
2225                 status = device_create_file(dev, &dev_attr_max_microvolts);
2226                 if (status < 0)
2227                         return status;
2228         }
2229         if (ops->set_current_limit) {
2230                 status = device_create_file(dev, &dev_attr_min_microamps);
2231                 if (status < 0)
2232                         return status;
2233                 status = device_create_file(dev, &dev_attr_max_microamps);
2234                 if (status < 0)
2235                         return status;
2236         }
2237
2238         /* suspend mode constraints need multiple supporting methods */
2239         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2240                 return status;
2241
2242         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2243         if (status < 0)
2244                 return status;
2245         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2246         if (status < 0)
2247                 return status;
2248         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2249         if (status < 0)
2250                 return status;
2251
2252         if (ops->set_suspend_voltage) {
2253                 status = device_create_file(dev,
2254                                 &dev_attr_suspend_standby_microvolts);
2255                 if (status < 0)
2256                         return status;
2257                 status = device_create_file(dev,
2258                                 &dev_attr_suspend_mem_microvolts);
2259                 if (status < 0)
2260                         return status;
2261                 status = device_create_file(dev,
2262                                 &dev_attr_suspend_disk_microvolts);
2263                 if (status < 0)
2264                         return status;
2265         }
2266
2267         if (ops->set_suspend_mode) {
2268                 status = device_create_file(dev,
2269                                 &dev_attr_suspend_standby_mode);
2270                 if (status < 0)
2271                         return status;
2272                 status = device_create_file(dev,
2273                                 &dev_attr_suspend_mem_mode);
2274                 if (status < 0)
2275                         return status;
2276                 status = device_create_file(dev,
2277                                 &dev_attr_suspend_disk_mode);
2278                 if (status < 0)
2279                         return status;
2280         }
2281
2282         return status;
2283 }
2284
2285 /**
2286  * regulator_register - register regulator
2287  * @regulator_desc: regulator to register
2288  * @dev: struct device for the regulator
2289  * @init_data: platform provided init data, passed through by driver
2290  * @driver_data: private regulator data
2291  *
2292  * Called by regulator drivers to register a regulator.
2293  * Returns 0 on success.
2294  */
2295 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2296         struct device *dev, struct regulator_init_data *init_data,
2297         void *driver_data)
2298 {
2299         static atomic_t regulator_no = ATOMIC_INIT(0);
2300         struct regulator_dev *rdev;
2301         int ret, i;
2302
2303         if (regulator_desc == NULL)
2304                 return ERR_PTR(-EINVAL);
2305
2306         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2307                 return ERR_PTR(-EINVAL);
2308
2309         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2310             regulator_desc->type != REGULATOR_CURRENT)
2311                 return ERR_PTR(-EINVAL);
2312
2313         if (!init_data)
2314                 return ERR_PTR(-EINVAL);
2315
2316         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2317         if (rdev == NULL)
2318                 return ERR_PTR(-ENOMEM);
2319
2320         mutex_lock(&regulator_list_mutex);
2321
2322         mutex_init(&rdev->mutex);
2323         rdev->reg_data = driver_data;
2324         rdev->owner = regulator_desc->owner;
2325         rdev->desc = regulator_desc;
2326         INIT_LIST_HEAD(&rdev->consumer_list);
2327         INIT_LIST_HEAD(&rdev->supply_list);
2328         INIT_LIST_HEAD(&rdev->list);
2329         INIT_LIST_HEAD(&rdev->slist);
2330         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2331
2332         /* preform any regulator specific init */
2333         if (init_data->regulator_init) {
2334                 ret = init_data->regulator_init(rdev->reg_data);
2335                 if (ret < 0)
2336                         goto clean;
2337         }
2338
2339         /* register with sysfs */
2340         rdev->dev.class = &regulator_class;
2341         rdev->dev.parent = dev;
2342         dev_set_name(&rdev->dev, "regulator.%d",
2343                      atomic_inc_return(&regulator_no) - 1);
2344         ret = device_register(&rdev->dev);
2345         if (ret != 0) {
2346                 put_device(&rdev->dev);
2347                 goto clean;
2348         }
2349
2350         dev_set_drvdata(&rdev->dev, rdev);
2351
2352         /* set regulator constraints */
2353         ret = set_machine_constraints(rdev, &init_data->constraints);
2354         if (ret < 0)
2355                 goto scrub;
2356
2357         /* add attributes supported by this regulator */
2358         ret = add_regulator_attributes(rdev);
2359         if (ret < 0)
2360                 goto scrub;
2361
2362         /* set supply regulator if it exists */
2363         if (init_data->supply_regulator && init_data->supply_regulator_dev) {
2364                 dev_err(dev,
2365                         "Supply regulator specified by both name and dev\n");
2366                 ret = -EINVAL;
2367                 goto scrub;
2368         }
2369
2370         if (init_data->supply_regulator) {
2371                 struct regulator_dev *r;
2372                 int found = 0;
2373
2374                 list_for_each_entry(r, &regulator_list, list) {
2375                         if (strcmp(rdev_get_name(r),
2376                                    init_data->supply_regulator) == 0) {
2377                                 found = 1;
2378                                 break;
2379                         }
2380                 }
2381
2382                 if (!found) {
2383                         dev_err(dev, "Failed to find supply %s\n",
2384                                 init_data->supply_regulator);
2385                         ret = -ENODEV;
2386                         goto scrub;
2387                 }
2388
2389                 ret = set_supply(rdev, r);
2390                 if (ret < 0)
2391                         goto scrub;
2392         }
2393
2394         if (init_data->supply_regulator_dev) {
2395                 dev_warn(dev, "Uses supply_regulator_dev instead of regulator_supply\n");
2396                 ret = set_supply(rdev,
2397                         dev_get_drvdata(init_data->supply_regulator_dev));
2398                 if (ret < 0)
2399                         goto scrub;
2400         }
2401
2402         /* add consumers devices */
2403         for (i = 0; i < init_data->num_consumer_supplies; i++) {
2404                 ret = set_consumer_device_supply(rdev,
2405                         init_data->consumer_supplies[i].dev,
2406                         init_data->consumer_supplies[i].dev_name,
2407                         init_data->consumer_supplies[i].supply);
2408                 if (ret < 0)
2409                         goto unset_supplies;
2410         }
2411
2412         list_add(&rdev->list, &regulator_list);
2413 out:
2414         mutex_unlock(&regulator_list_mutex);
2415         return rdev;
2416
2417 unset_supplies:
2418         unset_regulator_supplies(rdev);
2419
2420 scrub:
2421         device_unregister(&rdev->dev);
2422         /* device core frees rdev */
2423         rdev = ERR_PTR(ret);
2424         goto out;
2425
2426 clean:
2427         kfree(rdev);
2428         rdev = ERR_PTR(ret);
2429         goto out;
2430 }
2431 EXPORT_SYMBOL_GPL(regulator_register);
2432
2433 /**
2434  * regulator_unregister - unregister regulator
2435  * @rdev: regulator to unregister
2436  *
2437  * Called by regulator drivers to unregister a regulator.
2438  */
2439 void regulator_unregister(struct regulator_dev *rdev)
2440 {
2441         if (rdev == NULL)
2442                 return;
2443
2444         mutex_lock(&regulator_list_mutex);
2445         WARN_ON(rdev->open_count);
2446         unset_regulator_supplies(rdev);
2447         list_del(&rdev->list);
2448         if (rdev->supply)
2449                 sysfs_remove_link(&rdev->dev.kobj, "supply");
2450         device_unregister(&rdev->dev);
2451         mutex_unlock(&regulator_list_mutex);
2452 }
2453 EXPORT_SYMBOL_GPL(regulator_unregister);
2454
2455 /**
2456  * regulator_suspend_prepare - prepare regulators for system wide suspend
2457  * @state: system suspend state
2458  *
2459  * Configure each regulator with it's suspend operating parameters for state.
2460  * This will usually be called by machine suspend code prior to supending.
2461  */
2462 int regulator_suspend_prepare(suspend_state_t state)
2463 {
2464         struct regulator_dev *rdev;
2465         int ret = 0;
2466
2467         /* ON is handled by regulator active state */
2468         if (state == PM_SUSPEND_ON)
2469                 return -EINVAL;
2470
2471         mutex_lock(&regulator_list_mutex);
2472         list_for_each_entry(rdev, &regulator_list, list) {
2473
2474                 mutex_lock(&rdev->mutex);
2475                 ret = suspend_prepare(rdev, state);
2476                 mutex_unlock(&rdev->mutex);
2477
2478                 if (ret < 0) {
2479                         pr_err("failed to prepare %s\n", rdev_get_name(rdev));
2480                         goto out;
2481                 }
2482         }
2483 out:
2484         mutex_unlock(&regulator_list_mutex);
2485         return ret;
2486 }
2487 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2488
2489 /**
2490  * regulator_has_full_constraints - the system has fully specified constraints
2491  *
2492  * Calling this function will cause the regulator API to disable all
2493  * regulators which have a zero use count and don't have an always_on
2494  * constraint in a late_initcall.
2495  *
2496  * The intention is that this will become the default behaviour in a
2497  * future kernel release so users are encouraged to use this facility
2498  * now.
2499  */
2500 void regulator_has_full_constraints(void)
2501 {
2502         has_full_constraints = 1;
2503 }
2504 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2505
2506 /**
2507  * regulator_use_dummy_regulator - Provide a dummy regulator when none is found
2508  *
2509  * Calling this function will cause the regulator API to provide a
2510  * dummy regulator to consumers if no physical regulator is found,
2511  * allowing most consumers to proceed as though a regulator were
2512  * configured.  This allows systems such as those with software
2513  * controllable regulators for the CPU core only to be brought up more
2514  * readily.
2515  */
2516 void regulator_use_dummy_regulator(void)
2517 {
2518         board_wants_dummy_regulator = true;
2519 }
2520 EXPORT_SYMBOL_GPL(regulator_use_dummy_regulator);
2521
2522 /**
2523  * rdev_get_drvdata - get rdev regulator driver data
2524  * @rdev: regulator
2525  *
2526  * Get rdev regulator driver private data. This call can be used in the
2527  * regulator driver context.
2528  */
2529 void *rdev_get_drvdata(struct regulator_dev *rdev)
2530 {
2531         return rdev->reg_data;
2532 }
2533 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2534
2535 /**
2536  * regulator_get_drvdata - get regulator driver data
2537  * @regulator: regulator
2538  *
2539  * Get regulator driver private data. This call can be used in the consumer
2540  * driver context when non API regulator specific functions need to be called.
2541  */
2542 void *regulator_get_drvdata(struct regulator *regulator)
2543 {
2544         return regulator->rdev->reg_data;
2545 }
2546 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2547
2548 /**
2549  * regulator_set_drvdata - set regulator driver data
2550  * @regulator: regulator
2551  * @data: data
2552  */
2553 void regulator_set_drvdata(struct regulator *regulator, void *data)
2554 {
2555         regulator->rdev->reg_data = data;
2556 }
2557 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2558
2559 /**
2560  * regulator_get_id - get regulator ID
2561  * @rdev: regulator
2562  */
2563 int rdev_get_id(struct regulator_dev *rdev)
2564 {
2565         return rdev->desc->id;
2566 }
2567 EXPORT_SYMBOL_GPL(rdev_get_id);
2568
2569 struct device *rdev_get_dev(struct regulator_dev *rdev)
2570 {
2571         return &rdev->dev;
2572 }
2573 EXPORT_SYMBOL_GPL(rdev_get_dev);
2574
2575 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2576 {
2577         return reg_init_data->driver_data;
2578 }
2579 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2580
2581 static int __init regulator_init(void)
2582 {
2583         int ret;
2584
2585         printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2586
2587         ret = class_register(&regulator_class);
2588
2589         regulator_dummy_init();
2590
2591         return ret;
2592 }
2593
2594 /* init early to allow our consumers to complete system booting */
2595 core_initcall(regulator_init);
2596
2597 static int __init regulator_init_complete(void)
2598 {
2599         struct regulator_dev *rdev;
2600         struct regulator_ops *ops;
2601         struct regulation_constraints *c;
2602         int enabled, ret;
2603         const char *name;
2604
2605         mutex_lock(&regulator_list_mutex);
2606
2607         /* If we have a full configuration then disable any regulators
2608          * which are not in use or always_on.  This will become the
2609          * default behaviour in the future.
2610          */
2611         list_for_each_entry(rdev, &regulator_list, list) {
2612                 ops = rdev->desc->ops;
2613                 c = rdev->constraints;
2614
2615                 name = rdev_get_name(rdev);
2616
2617                 if (!ops->disable || (c && c->always_on))
2618                         continue;
2619
2620                 mutex_lock(&rdev->mutex);
2621
2622                 if (rdev->use_count)
2623                         goto unlock;
2624
2625                 /* If we can't read the status assume it's on. */
2626                 if (ops->is_enabled)
2627                         enabled = ops->is_enabled(rdev);
2628                 else
2629                         enabled = 1;
2630
2631                 if (!enabled)
2632                         goto unlock;
2633
2634                 if (has_full_constraints) {
2635                         /* We log since this may kill the system if it
2636                          * goes wrong. */
2637                         pr_info("disabling %s\n", name);
2638                         ret = ops->disable(rdev);
2639                         if (ret != 0) {
2640                                 pr_err("couldn't disable %s: %d\n", name, ret);
2641                         }
2642                 } else {
2643                         /* The intention is that in future we will
2644                          * assume that full constraints are provided
2645                          * so warn even if we aren't going to do
2646                          * anything here.
2647                          */
2648                         pr_warning("incomplete constraints, leaving %s on\n",
2649                                    name);
2650                 }
2651
2652 unlock:
2653                 mutex_unlock(&rdev->mutex);
2654         }
2655
2656         mutex_unlock(&regulator_list_mutex);
2657
2658         return 0;
2659 }
2660 late_initcall(regulator_init_complete);