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 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/debugfs.h>
  19 #include <linux/device.h>
  20 #include <linux/slab.h>
  21 #include <linux/async.h>
  22 #include <linux/err.h>
  23 #include <linux/mutex.h>
  24 #include <linux/suspend.h>
  25 #include <linux/delay.h>
  26 #include <linux/of.h>
  27 #include <linux/regulator/of_regulator.h>
  28 #include <linux/regulator/consumer.h>
  29 #include <linux/regulator/driver.h>
  30 #include <linux/regulator/machine.h>
  31 #include <linux/module.h>
  32
  33 #define CREATE_TRACE_POINTS
  34 #include <trace/events/regulator.h>
  35
  36 #include "dummy.h"
  37
  38 #define rdev_crit(rdev, fmt, ...)                                       \
  39         pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  40 #define rdev_err(rdev, fmt, ...)                                        \
  41         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  42 #define rdev_warn(rdev, fmt, ...)                                       \
  43         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  44 #define rdev_info(rdev, fmt, ...)                                       \
  45         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  46 #define rdev_dbg(rdev, fmt, ...)                                        \
  47         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  48
  49 static DEFINE_MUTEX(regulator_list_mutex);
  50 static LIST_HEAD(regulator_list);
  51 static LIST_HEAD(regulator_map_list);
  52 static bool has_full_constraints;
  53 static bool board_wants_dummy_regulator;
  54
  55 static struct dentry *debugfs_root;
  56
  57 /*
  58  * struct regulator_map
  59  *
  60  * Used to provide symbolic supply names to devices.
  61  */
  62 struct regulator_map {
  63         struct list_head list;
  64         const char *dev_name;   /* The dev_name() for the consumer */
  65         const char *supply;
  66         struct regulator_dev *regulator;
  67 };
  68
  69 /*
  70  * struct regulator
  71  *
  72  * One for each consumer device.
  73  */
  74 struct regulator {
  75         struct device *dev;
  76         struct list_head list;
  77         int uA_load;
  78         int min_uV;
  79         int max_uV;
  80         char *supply_name;
  81         struct device_attribute dev_attr;
  82         struct regulator_dev *rdev;
  83         struct dentry *debugfs;
  84 };
  85
  86 static int _regulator_is_enabled(struct regulator_dev *rdev);
  87 static int _regulator_disable(struct regulator_dev *rdev);
  88 static int _regulator_get_voltage(struct regulator_dev *rdev);
  89 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  90 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  91 static void _notifier_call_chain(struct regulator_dev *rdev,
  92                                   unsigned long event, void *data);
  93 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
  94                                      int min_uV, int max_uV);
  95 static struct regulator *create_regulator(struct regulator_dev *rdev,
  96                                           struct device *dev,
  97                                           const char *supply_name);
  98
  99 static const char *rdev_get_name(struct regulator_dev *rdev)
 100 {
 101         if (rdev->constraints && rdev->constraints->name)
 102                 return rdev->constraints->name;
 103         else if (rdev->desc->name)
 104                 return rdev->desc->name;
 105         else
 106                 return "";
 107 }
 108
 109 /* gets the regulator for a given consumer device */
 110 static struct regulator *get_device_regulator(struct device *dev)
 111 {
 112         struct regulator *regulator = NULL;
 113         struct regulator_dev *rdev;
 114
 115         mutex_lock(&regulator_list_mutex);
 116         list_for_each_entry(rdev, &regulator_list, list) {
 117                 mutex_lock(&rdev->mutex);
 118                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
 119                         if (regulator->dev == dev) {
 120                                 mutex_unlock(&rdev->mutex);
 121                                 mutex_unlock(&regulator_list_mutex);
 122                                 return regulator;
 123                         }
 124                 }
 125                 mutex_unlock(&rdev->mutex);
 126         }
 127         mutex_unlock(&regulator_list_mutex);
 128         return NULL;
 129 }
 130
 131 /**
 132  * of_get_regulator - get a regulator device node based on supply name
 133  * @dev: Device pointer for the consumer (of regulator) device
 134  * @supply: regulator supply name
 135  *
 136  * Extract the regulator device node corresponding to the supply name.
 137  * retruns the device node corresponding to the regulator if found, else
 138  * returns NULL.
 139  */
 140 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 141 {
 142         struct device_node *regnode = NULL;
 143         char prop_name[32]; /* 32 is max size of property name */
 144
 145         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 146
 147         snprintf(prop_name, 32, "%s-supply", supply);
 148         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 149
 150         if (!regnode) {
 151                 dev_warn(dev, "%s property in node %s references invalid phandle",
 152                                 prop_name, dev->of_node->full_name);
 153                 return NULL;
 154         }
 155         return regnode;
 156 }
 157
 158 /* Platform voltage constraint check */
 159 static int regulator_check_voltage(struct regulator_dev *rdev,
 160                                    int *min_uV, int *max_uV)
 161 {
 162         BUG_ON(*min_uV > *max_uV);
 163
 164         if (!rdev->constraints) {
 165                 rdev_err(rdev, "no constraints\n");
 166                 return -ENODEV;
 167         }
 168         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 169                 rdev_err(rdev, "operation not allowed\n");
 170                 return -EPERM;
 171         }
 172
 173         if (*max_uV > rdev->constraints->max_uV)
 174                 *max_uV = rdev->constraints->max_uV;
 175         if (*min_uV < rdev->constraints->min_uV)
 176                 *min_uV = rdev->constraints->min_uV;
 177
 178         if (*min_uV > *max_uV) {
 179                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 180                          *min_uV, *max_uV);
 181                 return -EINVAL;
 182         }
 183
 184         return 0;
 185 }
 186
 187 /* Make sure we select a voltage that suits the needs of all
 188  * regulator consumers
 189  */
 190 static int regulator_check_consumers(struct regulator_dev *rdev,
 191                                      int *min_uV, int *max_uV)
 192 {
 193         struct regulator *regulator;
 194
 195         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 196                 /*
 197                  * Assume consumers that didn't say anything are OK
 198                  * with anything in the constraint range.
 199                  */
 200                 if (!regulator->min_uV && !regulator->max_uV)
 201                         continue;
 202
 203                 if (*max_uV > regulator->max_uV)
 204                         *max_uV = regulator->max_uV;
 205                 if (*min_uV < regulator->min_uV)
 206                         *min_uV = regulator->min_uV;
 207         }
 208
 209         if (*min_uV > *max_uV)
 210                 return -EINVAL;
 211
 212         return 0;
 213 }
 214
 215 /* current constraint check */
 216 static int regulator_check_current_limit(struct regulator_dev *rdev,
 217                                         int *min_uA, int *max_uA)
 218 {
 219         BUG_ON(*min_uA > *max_uA);
 220
 221         if (!rdev->constraints) {
 222                 rdev_err(rdev, "no constraints\n");
 223                 return -ENODEV;
 224         }
 225         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 226                 rdev_err(rdev, "operation not allowed\n");
 227                 return -EPERM;
 228         }
 229
 230         if (*max_uA > rdev->constraints->max_uA)
 231                 *max_uA = rdev->constraints->max_uA;
 232         if (*min_uA < rdev->constraints->min_uA)
 233                 *min_uA = rdev->constraints->min_uA;
 234
 235         if (*min_uA > *max_uA) {
 236                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 237                          *min_uA, *max_uA);
 238                 return -EINVAL;
 239         }
 240
 241         return 0;
 242 }
 243
 244 /* operating mode constraint check */
 245 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
 246 {
 247         switch (*mode) {
 248         case REGULATOR_MODE_FAST:
 249         case REGULATOR_MODE_NORMAL:
 250         case REGULATOR_MODE_IDLE:
 251         case REGULATOR_MODE_STANDBY:
 252                 break;
 253         default:
 254                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 255                 return -EINVAL;
 256         }
 257
 258         if (!rdev->constraints) {
 259                 rdev_err(rdev, "no constraints\n");
 260                 return -ENODEV;
 261         }
 262         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 263                 rdev_err(rdev, "operation not allowed\n");
 264                 return -EPERM;
 265         }
 266
 267         /* The modes are bitmasks, the most power hungry modes having
 268          * the lowest values. If the requested mode isn't supported
 269          * try higher modes. */
 270         while (*mode) {
 271                 if (rdev->constraints->valid_modes_mask & *mode)
 272                         return 0;
 273                 *mode /= 2;
 274         }
 275
 276         return -EINVAL;
 277 }
 278
 279 /* dynamic regulator mode switching constraint check */
 280 static int regulator_check_drms(struct regulator_dev *rdev)
 281 {
 282         if (!rdev->constraints) {
 283                 rdev_err(rdev, "no constraints\n");
 284                 return -ENODEV;
 285         }
 286         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 287                 rdev_err(rdev, "operation not allowed\n");
 288                 return -EPERM;
 289         }
 290         return 0;
 291 }
 292
 293 static ssize_t device_requested_uA_show(struct device *dev,
 294                              struct device_attribute *attr, char *buf)
 295 {
 296         struct regulator *regulator;
 297
 298         regulator = get_device_regulator(dev);
 299         if (regulator == NULL)
 300                 return 0;
 301
 302         return sprintf(buf, "%d\n", regulator->uA_load);
 303 }
 304
 305 static ssize_t regulator_uV_show(struct device *dev,
 306                                 struct device_attribute *attr, char *buf)
 307 {
 308         struct regulator_dev *rdev = dev_get_drvdata(dev);
 309         ssize_t ret;
 310
 311         mutex_lock(&rdev->mutex);
 312         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 313         mutex_unlock(&rdev->mutex);
 314
 315         return ret;
 316 }
 317 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 318
 319 static ssize_t regulator_uA_show(struct device *dev,
 320                                 struct device_attribute *attr, char *buf)
 321 {
 322         struct regulator_dev *rdev = dev_get_drvdata(dev);
 323
 324         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 325 }
 326 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 327
 328 static ssize_t regulator_name_show(struct device *dev,
 329                              struct device_attribute *attr, char *buf)
 330 {
 331         struct regulator_dev *rdev = dev_get_drvdata(dev);
 332
 333         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 334 }
 335
 336 static ssize_t regulator_print_opmode(char *buf, int mode)
 337 {
 338         switch (mode) {
 339         case REGULATOR_MODE_FAST:
 340                 return sprintf(buf, "fast\n");
 341         case REGULATOR_MODE_NORMAL:
 342                 return sprintf(buf, "normal\n");
 343         case REGULATOR_MODE_IDLE:
 344                 return sprintf(buf, "idle\n");
 345         case REGULATOR_MODE_STANDBY:
 346                 return sprintf(buf, "standby\n");
 347         }
 348         return sprintf(buf, "unknown\n");
 349 }
 350
 351 static ssize_t regulator_opmode_show(struct device *dev,
 352                                     struct device_attribute *attr, char *buf)
 353 {
 354         struct regulator_dev *rdev = dev_get_drvdata(dev);
 355
 356         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 357 }
 358 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 359
 360 static ssize_t regulator_print_state(char *buf, int state)
 361 {
 362         if (state > 0)
 363                 return sprintf(buf, "enabled\n");
 364         else if (state == 0)
 365                 return sprintf(buf, "disabled\n");
 366         else
 367                 return sprintf(buf, "unknown\n");
 368 }
 369
 370 static ssize_t regulator_state_show(struct device *dev,
 371                                    struct device_attribute *attr, char *buf)
 372 {
 373         struct regulator_dev *rdev = dev_get_drvdata(dev);
 374         ssize_t ret;
 375
 376         mutex_lock(&rdev->mutex);
 377         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 378         mutex_unlock(&rdev->mutex);
 379
 380         return ret;
 381 }
 382 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 383
 384 static ssize_t regulator_status_show(struct device *dev,
 385                                    struct device_attribute *attr, char *buf)
 386 {
 387         struct regulator_dev *rdev = dev_get_drvdata(dev);
 388         int status;
 389         char *label;
 390
 391         status = rdev->desc->ops->get_status(rdev);
 392         if (status < 0)
 393                 return status;
 394
 395         switch (status) {
 396         case REGULATOR_STATUS_OFF:
 397                 label = "off";
 398                 break;
 399         case REGULATOR_STATUS_ON:
 400                 label = "on";
 401                 break;
 402         case REGULATOR_STATUS_ERROR:
 403                 label = "error";
 404                 break;
 405         case REGULATOR_STATUS_FAST:
 406                 label = "fast";
 407                 break;
 408         case REGULATOR_STATUS_NORMAL:
 409                 label = "normal";
 410                 break;
 411         case REGULATOR_STATUS_IDLE:
 412                 label = "idle";
 413                 break;
 414         case REGULATOR_STATUS_STANDBY:
 415                 label = "standby";
 416                 break;
 417         default:
 418                 return -ERANGE;
 419         }
 420
 421         return sprintf(buf, "%s\n", label);
 422 }
 423 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 424
 425 static ssize_t regulator_min_uA_show(struct device *dev,
 426                                     struct device_attribute *attr, char *buf)
 427 {
 428         struct regulator_dev *rdev = dev_get_drvdata(dev);
 429
 430         if (!rdev->constraints)
 431                 return sprintf(buf, "constraint not defined\n");
 432
 433         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 434 }
 435 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 436
 437 static ssize_t regulator_max_uA_show(struct device *dev,
 438                                     struct device_attribute *attr, char *buf)
 439 {
 440         struct regulator_dev *rdev = dev_get_drvdata(dev);
 441
 442         if (!rdev->constraints)
 443                 return sprintf(buf, "constraint not defined\n");
 444
 445         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 446 }
 447 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 448
 449 static ssize_t regulator_min_uV_show(struct device *dev,
 450                                     struct device_attribute *attr, char *buf)
 451 {
 452         struct regulator_dev *rdev = dev_get_drvdata(dev);
 453
 454         if (!rdev->constraints)
 455                 return sprintf(buf, "constraint not defined\n");
 456
 457         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 458 }
 459 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 460
 461 static ssize_t regulator_max_uV_show(struct device *dev,
 462                                     struct device_attribute *attr, char *buf)
 463 {
 464         struct regulator_dev *rdev = dev_get_drvdata(dev);
 465
 466         if (!rdev->constraints)
 467                 return sprintf(buf, "constraint not defined\n");
 468
 469         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 470 }
 471 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 472
 473 static ssize_t regulator_total_uA_show(struct device *dev,
 474                                       struct device_attribute *attr, char *buf)
 475 {
 476         struct regulator_dev *rdev = dev_get_drvdata(dev);
 477         struct regulator *regulator;
 478         int uA = 0;
 479
 480         mutex_lock(&rdev->mutex);
 481         list_for_each_entry(regulator, &rdev->consumer_list, list)
 482                 uA += regulator->uA_load;
 483         mutex_unlock(&rdev->mutex);
 484         return sprintf(buf, "%d\n", uA);
 485 }
 486 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 487
 488 static ssize_t regulator_num_users_show(struct device *dev,
 489                                       struct device_attribute *attr, char *buf)
 490 {
 491         struct regulator_dev *rdev = dev_get_drvdata(dev);
 492         return sprintf(buf, "%d\n", rdev->use_count);
 493 }
 494
 495 static ssize_t regulator_type_show(struct device *dev,
 496                                   struct device_attribute *attr, char *buf)
 497 {
 498         struct regulator_dev *rdev = dev_get_drvdata(dev);
 499
 500         switch (rdev->desc->type) {
 501         case REGULATOR_VOLTAGE:
 502                 return sprintf(buf, "voltage\n");
 503         case REGULATOR_CURRENT:
 504                 return sprintf(buf, "current\n");
 505         }
 506         return sprintf(buf, "unknown\n");
 507 }
 508
 509 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 510                                 struct device_attribute *attr, char *buf)
 511 {
 512         struct regulator_dev *rdev = dev_get_drvdata(dev);
 513
 514         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 515 }
 516 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 517                 regulator_suspend_mem_uV_show, NULL);
 518
 519 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 520                                 struct device_attribute *attr, char *buf)
 521 {
 522         struct regulator_dev *rdev = dev_get_drvdata(dev);
 523
 524         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 525 }
 526 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 527                 regulator_suspend_disk_uV_show, NULL);
 528
 529 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 530                                 struct device_attribute *attr, char *buf)
 531 {
 532         struct regulator_dev *rdev = dev_get_drvdata(dev);
 533
 534         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 535 }
 536 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 537                 regulator_suspend_standby_uV_show, NULL);
 538
 539 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 540                                 struct device_attribute *attr, char *buf)
 541 {
 542         struct regulator_dev *rdev = dev_get_drvdata(dev);
 543
 544         return regulator_print_opmode(buf,
 545                 rdev->constraints->state_mem.mode);
 546 }
 547 static DEVICE_ATTR(suspend_mem_mode, 0444,
 548                 regulator_suspend_mem_mode_show, NULL);
 549
 550 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 551                                 struct device_attribute *attr, char *buf)
 552 {
 553         struct regulator_dev *rdev = dev_get_drvdata(dev);
 554
 555         return regulator_print_opmode(buf,
 556                 rdev->constraints->state_disk.mode);
 557 }
 558 static DEVICE_ATTR(suspend_disk_mode, 0444,
 559                 regulator_suspend_disk_mode_show, NULL);
 560
 561 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 562                                 struct device_attribute *attr, char *buf)
 563 {
 564         struct regulator_dev *rdev = dev_get_drvdata(dev);
 565
 566         return regulator_print_opmode(buf,
 567                 rdev->constraints->state_standby.mode);
 568 }
 569 static DEVICE_ATTR(suspend_standby_mode, 0444,
 570                 regulator_suspend_standby_mode_show, NULL);
 571
 572 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 573                                    struct device_attribute *attr, char *buf)
 574 {
 575         struct regulator_dev *rdev = dev_get_drvdata(dev);
 576
 577         return regulator_print_state(buf,
 578                         rdev->constraints->state_mem.enabled);
 579 }
 580 static DEVICE_ATTR(suspend_mem_state, 0444,
 581                 regulator_suspend_mem_state_show, NULL);
 582
 583 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 584                                    struct device_attribute *attr, char *buf)
 585 {
 586         struct regulator_dev *rdev = dev_get_drvdata(dev);
 587
 588         return regulator_print_state(buf,
 589                         rdev->constraints->state_disk.enabled);
 590 }
 591 static DEVICE_ATTR(suspend_disk_state, 0444,
 592                 regulator_suspend_disk_state_show, NULL);
 593
 594 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 595                                    struct device_attribute *attr, char *buf)
 596 {
 597         struct regulator_dev *rdev = dev_get_drvdata(dev);
 598
 599         return regulator_print_state(buf,
 600                         rdev->constraints->state_standby.enabled);
 601 }
 602 static DEVICE_ATTR(suspend_standby_state, 0444,
 603                 regulator_suspend_standby_state_show, NULL);
 604
 605
 606 /*
 607  * These are the only attributes are present for all regulators.
 608  * Other attributes are a function of regulator functionality.
 609  */
 610 static struct device_attribute regulator_dev_attrs[] = {
 611         __ATTR(name, 0444, regulator_name_show, NULL),
 612         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
 613         __ATTR(type, 0444, regulator_type_show, NULL),
 614         __ATTR_NULL,
 615 };
 616
 617 static void regulator_dev_release(struct device *dev)
 618 {
 619         struct regulator_dev *rdev = dev_get_drvdata(dev);
 620         kfree(rdev);
 621 }
 622
 623 static struct class regulator_class = {
 624         .name = "regulator",
 625         .dev_release = regulator_dev_release,
 626         .dev_attrs = regulator_dev_attrs,
 627 };
 628
 629 /* Calculate the new optimum regulator operating mode based on the new total
 630  * consumer load. All locks held by caller */
 631 static void drms_uA_update(struct regulator_dev *rdev)
 632 {
 633         struct regulator *sibling;
 634         int current_uA = 0, output_uV, input_uV, err;
 635         unsigned int mode;
 636
 637         err = regulator_check_drms(rdev);
 638         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 639             (!rdev->desc->ops->get_voltage &&
 640              !rdev->desc->ops->get_voltage_sel) ||
 641             !rdev->desc->ops->set_mode)
 642                 return;
 643
 644         /* get output voltage */
 645         output_uV = _regulator_get_voltage(rdev);
 646         if (output_uV <= 0)
 647                 return;
 648
 649         /* get input voltage */
 650         input_uV = 0;
 651         if (rdev->supply)
 652                 input_uV = _regulator_get_voltage(rdev);
 653         if (input_uV <= 0)
 654                 input_uV = rdev->constraints->input_uV;
 655         if (input_uV <= 0)
 656                 return;
 657
 658         /* calc total requested load */
 659         list_for_each_entry(sibling, &rdev->consumer_list, list)
 660                 current_uA += sibling->uA_load;
 661
 662         /* now get the optimum mode for our new total regulator load */
 663         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 664                                                   output_uV, current_uA);
 665
 666         /* check the new mode is allowed */
 667         err = regulator_mode_constrain(rdev, &mode);
 668         if (err == 0)
 669                 rdev->desc->ops->set_mode(rdev, mode);
 670 }
 671
 672 static int suspend_set_state(struct regulator_dev *rdev,
 673         struct regulator_state *rstate)
 674 {
 675         int ret = 0;
 676         bool can_set_state;
 677
 678         can_set_state = rdev->desc->ops->set_suspend_enable &&
 679                 rdev->desc->ops->set_suspend_disable;
 680
 681         /* If we have no suspend mode configration don't set anything;
 682          * only warn if the driver actually makes the suspend mode
 683          * configurable.
 684          */
 685         if (!rstate->enabled && !rstate->disabled) {
 686                 if (can_set_state)
 687                         rdev_warn(rdev, "No configuration\n");
 688                 return 0;
 689         }
 690
 691         if (rstate->enabled && rstate->disabled) {
 692                 rdev_err(rdev, "invalid configuration\n");
 693                 return -EINVAL;
 694         }
 695
 696         if (!can_set_state) {
 697                 rdev_err(rdev, "no way to set suspend state\n");
 698                 return -EINVAL;
 699         }
 700
 701         if (rstate->enabled)
 702                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 703         else
 704                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 705         if (ret < 0) {
 706                 rdev_err(rdev, "failed to enabled/disable\n");
 707                 return ret;
 708         }
 709
 710         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 711                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 712                 if (ret < 0) {
 713                         rdev_err(rdev, "failed to set voltage\n");
 714                         return ret;
 715                 }
 716         }
 717
 718         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 719                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 720                 if (ret < 0) {
 721                         rdev_err(rdev, "failed to set mode\n");
 722                         return ret;
 723                 }
 724         }
 725         return ret;
 726 }
 727
 728 /* locks held by caller */
 729 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 730 {
 731         if (!rdev->constraints)
 732                 return -EINVAL;
 733
 734         switch (state) {
 735         case PM_SUSPEND_STANDBY:
 736                 return suspend_set_state(rdev,
 737                         &rdev->constraints->state_standby);
 738         case PM_SUSPEND_MEM:
 739                 return suspend_set_state(rdev,
 740                         &rdev->constraints->state_mem);
 741         case PM_SUSPEND_MAX:
 742                 return suspend_set_state(rdev,
 743                         &rdev->constraints->state_disk);
 744         default:
 745                 return -EINVAL;
 746         }
 747 }
 748
 749 static void print_constraints(struct regulator_dev *rdev)
 750 {
 751         struct regulation_constraints *constraints = rdev->constraints;
 752         char buf[80] = "";
 753         int count = 0;
 754         int ret;
 755
 756         if (constraints->min_uV && constraints->max_uV) {
 757                 if (constraints->min_uV == constraints->max_uV)
 758                         count += sprintf(buf + count, "%d mV ",
 759                                          constraints->min_uV / 1000);
 760                 else
 761                         count += sprintf(buf + count, "%d <--> %d mV ",
 762                                          constraints->min_uV / 1000,
 763                                          constraints->max_uV / 1000);
 764         }
 765
 766         if (!constraints->min_uV ||
 767             constraints->min_uV != constraints->max_uV) {
 768                 ret = _regulator_get_voltage(rdev);
 769                 if (ret > 0)
 770                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 771         }
 772
 773         if (constraints->uV_offset)
 774                 count += sprintf(buf, "%dmV offset ",
 775                                  constraints->uV_offset / 1000);
 776
 777         if (constraints->min_uA && constraints->max_uA) {
 778                 if (constraints->min_uA == constraints->max_uA)
 779                         count += sprintf(buf + count, "%d mA ",
 780                                          constraints->min_uA / 1000);
 781                 else
 782                         count += sprintf(buf + count, "%d <--> %d mA ",
 783                                          constraints->min_uA / 1000,
 784                                          constraints->max_uA / 1000);
 785         }
 786
 787         if (!constraints->min_uA ||
 788             constraints->min_uA != constraints->max_uA) {
 789                 ret = _regulator_get_current_limit(rdev);
 790                 if (ret > 0)
 791                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
 792         }
 793
 794         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 795                 count += sprintf(buf + count, "fast ");
 796         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 797                 count += sprintf(buf + count, "normal ");
 798         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 799                 count += sprintf(buf + count, "idle ");
 800         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 801                 count += sprintf(buf + count, "standby");
 802
 803         rdev_info(rdev, "%s\n", buf);
 804
 805         if ((constraints->min_uV != constraints->max_uV) &&
 806             !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
 807                 rdev_warn(rdev,
 808                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
 809 }
 810
 811 static int machine_constraints_voltage(struct regulator_dev *rdev,
 812         struct regulation_constraints *constraints)
 813 {
 814         struct regulator_ops *ops = rdev->desc->ops;
 815         int ret;
 816
 817         /* do we need to apply the constraint voltage */
 818         if (rdev->constraints->apply_uV &&
 819             rdev->constraints->min_uV == rdev->constraints->max_uV) {
 820                 ret = _regulator_do_set_voltage(rdev,
 821                                                 rdev->constraints->min_uV,
 822                                                 rdev->constraints->max_uV);
 823                 if (ret < 0) {
 824                         rdev_err(rdev, "failed to apply %duV constraint\n",
 825                                  rdev->constraints->min_uV);
 826                         return ret;
 827                 }
 828         }
 829
 830         /* constrain machine-level voltage specs to fit
 831          * the actual range supported by this regulator.
 832          */
 833         if (ops->list_voltage && rdev->desc->n_voltages) {
 834                 int     count = rdev->desc->n_voltages;
 835                 int     i;
 836                 int     min_uV = INT_MAX;
 837                 int     max_uV = INT_MIN;
 838                 int     cmin = constraints->min_uV;
 839                 int     cmax = constraints->max_uV;
 840
 841                 /* it's safe to autoconfigure fixed-voltage supplies
 842                    and the constraints are used by list_voltage. */
 843                 if (count == 1 && !cmin) {
 844                         cmin = 1;
 845                         cmax = INT_MAX;
 846                         constraints->min_uV = cmin;
 847                         constraints->max_uV = cmax;
 848                 }
 849
 850                 /* voltage constraints are optional */
 851                 if ((cmin == 0) && (cmax == 0))
 852                         return 0;
 853
 854                 /* else require explicit machine-level constraints */
 855                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 856                         rdev_err(rdev, "invalid voltage constraints\n");
 857                         return -EINVAL;
 858                 }
 859
 860                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 861                 for (i = 0; i < count; i++) {
 862                         int     value;
 863
 864                         value = ops->list_voltage(rdev, i);
 865                         if (value <= 0)
 866                                 continue;
 867
 868                         /* maybe adjust [min_uV..max_uV] */
 869                         if (value >= cmin && value < min_uV)
 870                                 min_uV = value;
 871                         if (value <= cmax && value > max_uV)
 872                                 max_uV = value;
 873                 }
 874
 875                 /* final: [min_uV..max_uV] valid iff constraints valid */
 876                 if (max_uV < min_uV) {
 877                         rdev_err(rdev, "unsupportable voltage constraints\n");
 878                         return -EINVAL;
 879                 }
 880
 881                 /* use regulator's subset of machine constraints */
 882                 if (constraints->min_uV < min_uV) {
 883                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
 884                                  constraints->min_uV, min_uV);
 885                         constraints->min_uV = min_uV;
 886                 }
 887                 if (constraints->max_uV > max_uV) {
 888                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
 889                                  constraints->max_uV, max_uV);
 890                         constraints->max_uV = max_uV;
 891                 }
 892         }
 893
 894         return 0;
 895 }
 896
 897 /**
 898  * set_machine_constraints - sets regulator constraints
 899  * @rdev: regulator source
 900  * @constraints: constraints to apply
 901  *
 902  * Allows platform initialisation code to define and constrain
 903  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 904  * Constraints *must* be set by platform code in order for some
 905  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 906  * set_mode.
 907  */
 908 static int set_machine_constraints(struct regulator_dev *rdev,
 909         const struct regulation_constraints *constraints)
 910 {
 911         int ret = 0;
 912         struct regulator_ops *ops = rdev->desc->ops;
 913
 914         if (constraints)
 915                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
 916                                             GFP_KERNEL);
 917         else
 918                 rdev->constraints = kzalloc(sizeof(*constraints),
 919                                             GFP_KERNEL);
 920         if (!rdev->constraints)
 921                 return -ENOMEM;
 922
 923         ret = machine_constraints_voltage(rdev, rdev->constraints);
 924         if (ret != 0)
 925                 goto out;
 926
 927         /* do we need to setup our suspend state */
 928         if (rdev->constraints->initial_state) {
 929                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
 930                 if (ret < 0) {
 931                         rdev_err(rdev, "failed to set suspend state\n");
 932                         goto out;
 933                 }
 934         }
 935
 936         if (rdev->constraints->initial_mode) {
 937                 if (!ops->set_mode) {
 938                         rdev_err(rdev, "no set_mode operation\n");
 939                         ret = -EINVAL;
 940                         goto out;
 941                 }
 942
 943                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
 944                 if (ret < 0) {
 945                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
 946                         goto out;
 947                 }
 948         }
 949
 950         /* If the constraints say the regulator should be on at this point
 951          * and we have control then make sure it is enabled.
 952          */
 953         if ((rdev->constraints->always_on || rdev->constraints->boot_on) &&
 954             ops->enable) {
 955                 ret = ops->enable(rdev);
 956                 if (ret < 0) {
 957                         rdev_err(rdev, "failed to enable\n");
 958                         goto out;
 959                 }
 960         }
 961
 962         print_constraints(rdev);
 963         return 0;
 964 out:
 965         kfree(rdev->constraints);
 966         rdev->constraints = NULL;
 967         return ret;
 968 }
 969
 970 /**
 971  * set_supply - set regulator supply regulator
 972  * @rdev: regulator name
 973  * @supply_rdev: supply regulator name
 974  *
 975  * Called by platform initialisation code to set the supply regulator for this
 976  * regulator. This ensures that a regulators supply will also be enabled by the
 977  * core if it's child is enabled.
 978  */
 979 static int set_supply(struct regulator_dev *rdev,
 980                       struct regulator_dev *supply_rdev)
 981 {
 982         int err;
 983
 984         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
 985
 986         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
 987         if (rdev->supply == NULL) {
 988                 err = -ENOMEM;
 989                 return err;
 990         }
 991
 992         return 0;
 993 }
 994
 995 /**
 996  * set_consumer_device_supply - Bind a regulator to a symbolic supply
 997  * @rdev:         regulator source
 998  * @consumer_dev: device the supply applies to
 999  * @consumer_dev_name: dev_name() string for device supply applies to
1000  * @supply:       symbolic name for supply
1001  *
1002  * Allows platform initialisation code to map physical regulator
1003  * sources to symbolic names for supplies for use by devices.  Devices
1004  * should use these symbolic names to request regulators, avoiding the
1005  * need to provide board-specific regulator names as platform data.
1006  *
1007  * Only one of consumer_dev and consumer_dev_name may be specified.
1008  */
1009 static int set_consumer_device_supply(struct regulator_dev *rdev,
1010         struct device *consumer_dev, const char *consumer_dev_name,
1011         const char *supply)
1012 {
1013         struct regulator_map *node;
1014         int has_dev;
1015
1016         if (consumer_dev && consumer_dev_name)
1017                 return -EINVAL;
1018
1019         if (!consumer_dev_name && consumer_dev)
1020                 consumer_dev_name = dev_name(consumer_dev);
1021
1022         if (supply == NULL)
1023                 return -EINVAL;
1024
1025         if (consumer_dev_name != NULL)
1026                 has_dev = 1;
1027         else
1028                 has_dev = 0;
1029
1030         list_for_each_entry(node, &regulator_map_list, list) {
1031                 if (node->dev_name && consumer_dev_name) {
1032                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1033                                 continue;
1034                 } else if (node->dev_name || consumer_dev_name) {
1035                         continue;
1036                 }
1037
1038                 if (strcmp(node->supply, supply) != 0)
1039                         continue;
1040
1041                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
1042                         dev_name(&node->regulator->dev),
1043                         node->regulator->desc->name,
1044                         supply,
1045                         dev_name(&rdev->dev), rdev_get_name(rdev));
1046                 return -EBUSY;
1047         }
1048
1049         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1050         if (node == NULL)
1051                 return -ENOMEM;
1052
1053         node->regulator = rdev;
1054         node->supply = supply;
1055
1056         if (has_dev) {
1057                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1058                 if (node->dev_name == NULL) {
1059                         kfree(node);
1060                         return -ENOMEM;
1061                 }
1062         }
1063
1064         list_add(&node->list, &regulator_map_list);
1065         return 0;
1066 }
1067
1068 static void unset_regulator_supplies(struct regulator_dev *rdev)
1069 {
1070         struct regulator_map *node, *n;
1071
1072         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1073                 if (rdev == node->regulator) {
1074                         list_del(&node->list);
1075                         kfree(node->dev_name);
1076                         kfree(node);
1077                 }
1078         }
1079 }
1080
1081 #define REG_STR_SIZE    64
1082
1083 static struct regulator *create_regulator(struct regulator_dev *rdev,
1084                                           struct device *dev,
1085                                           const char *supply_name)
1086 {
1087         struct regulator *regulator;
1088         char buf[REG_STR_SIZE];
1089         int err, size;
1090
1091         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1092         if (regulator == NULL)
1093                 return NULL;
1094
1095         mutex_lock(&rdev->mutex);
1096         regulator->rdev = rdev;
1097         list_add(&regulator->list, &rdev->consumer_list);
1098
1099         if (dev) {
1100                 /* create a 'requested_microamps_name' sysfs entry */
1101                 size = scnprintf(buf, REG_STR_SIZE,
1102                                  "microamps_requested_%s-%s",
1103                                  dev_name(dev), supply_name);
1104                 if (size >= REG_STR_SIZE)
1105                         goto overflow_err;
1106
1107                 regulator->dev = dev;
1108                 sysfs_attr_init(&regulator->dev_attr.attr);
1109                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1110                 if (regulator->dev_attr.attr.name == NULL)
1111                         goto attr_name_err;
1112
1113                 regulator->dev_attr.attr.mode = 0444;
1114                 regulator->dev_attr.show = device_requested_uA_show;
1115                 err = device_create_file(dev, &regulator->dev_attr);
1116                 if (err < 0) {
1117                         rdev_warn(rdev, "could not add regulator_dev requested microamps sysfs entry\n");
1118                         goto attr_name_err;
1119                 }
1120
1121                 /* also add a link to the device sysfs entry */
1122                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1123                                  dev->kobj.name, supply_name);
1124                 if (size >= REG_STR_SIZE)
1125                         goto attr_err;
1126
1127                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1128                 if (regulator->supply_name == NULL)
1129                         goto attr_err;
1130
1131                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1132                                         buf);
1133                 if (err) {
1134                         rdev_warn(rdev, "could not add device link %s err %d\n",
1135                                   dev->kobj.name, err);
1136                         goto link_name_err;
1137                 }
1138         } else {
1139                 regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1140                 if (regulator->supply_name == NULL)
1141                         goto attr_err;
1142         }
1143
1144         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1145                                                 rdev->debugfs);
1146         if (!regulator->debugfs) {
1147                 rdev_warn(rdev, "Failed to create debugfs directory\n");
1148         } else {
1149                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1150                                    &regulator->uA_load);
1151                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1152                                    &regulator->min_uV);
1153                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1154                                    &regulator->max_uV);
1155         }
1156
1157         mutex_unlock(&rdev->mutex);
1158         return regulator;
1159 link_name_err:
1160         kfree(regulator->supply_name);
1161 attr_err:
1162         device_remove_file(regulator->dev, &regulator->dev_attr);
1163 attr_name_err:
1164         kfree(regulator->dev_attr.attr.name);
1165 overflow_err:
1166         list_del(&regulator->list);
1167         kfree(regulator);
1168         mutex_unlock(&rdev->mutex);
1169         return NULL;
1170 }
1171
1172 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1173 {
1174         if (!rdev->desc->ops->enable_time)
1175                 return 0;
1176         return rdev->desc->ops->enable_time(rdev);
1177 }
1178
1179 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1180                                                          const char *supply)
1181 {
1182         struct regulator_dev *r;
1183         struct device_node *node;
1184
1185         /* first do a dt based lookup */
1186         if (dev && dev->of_node) {
1187                 node = of_get_regulator(dev, supply);
1188                 if (node)
1189                         list_for_each_entry(r, &regulator_list, list)
1190                                 if (r->dev.parent &&
1191                                         node == r->dev.of_node)
1192                                         return r;
1193         }
1194
1195         /* if not found, try doing it non-dt way */
1196         list_for_each_entry(r, &regulator_list, list)
1197                 if (strcmp(rdev_get_name(r), supply) == 0)
1198                         return r;
1199
1200         return NULL;
1201 }
1202
1203 /* Internal regulator request function */
1204 static struct regulator *_regulator_get(struct device *dev, const char *id,
1205                                         int exclusive)
1206 {
1207         struct regulator_dev *rdev;
1208         struct regulator_map *map;
1209         struct regulator *regulator = ERR_PTR(-ENODEV);
1210         const char *devname = NULL;
1211         int ret;
1212
1213         if (id == NULL) {
1214                 pr_err("get() with no identifier\n");
1215                 return regulator;
1216         }
1217
1218         if (dev)
1219                 devname = dev_name(dev);
1220
1221         mutex_lock(&regulator_list_mutex);
1222
1223         rdev = regulator_dev_lookup(dev, id);
1224         if (rdev)
1225                 goto found;
1226
1227         list_for_each_entry(map, &regulator_map_list, list) {
1228                 /* If the mapping has a device set up it must match */
1229                 if (map->dev_name &&
1230                     (!devname || strcmp(map->dev_name, devname)))
1231                         continue;
1232
1233                 if (strcmp(map->supply, id) == 0) {
1234                         rdev = map->regulator;
1235                         goto found;
1236                 }
1237         }
1238
1239         if (board_wants_dummy_regulator) {
1240                 rdev = dummy_regulator_rdev;
1241                 goto found;
1242         }
1243
1244 #ifdef CONFIG_REGULATOR_DUMMY
1245         if (!devname)
1246                 devname = "deviceless";
1247
1248         /* If the board didn't flag that it was fully constrained then
1249          * substitute in a dummy regulator so consumers can continue.
1250          */
1251         if (!has_full_constraints) {
1252                 pr_warn("%s supply %s not found, using dummy regulator\n",
1253                         devname, id);
1254                 rdev = dummy_regulator_rdev;
1255                 goto found;
1256         }
1257 #endif
1258
1259         mutex_unlock(&regulator_list_mutex);
1260         return regulator;
1261
1262 found:
1263         if (rdev->exclusive) {
1264                 regulator = ERR_PTR(-EPERM);
1265                 goto out;
1266         }
1267
1268         if (exclusive && rdev->open_count) {
1269                 regulator = ERR_PTR(-EBUSY);
1270                 goto out;
1271         }
1272
1273         if (!try_module_get(rdev->owner))
1274                 goto out;
1275
1276         regulator = create_regulator(rdev, dev, id);
1277         if (regulator == NULL) {
1278                 regulator = ERR_PTR(-ENOMEM);
1279                 module_put(rdev->owner);
1280                 goto out;
1281         }
1282
1283         rdev->open_count++;
1284         if (exclusive) {
1285                 rdev->exclusive = 1;
1286
1287                 ret = _regulator_is_enabled(rdev);
1288                 if (ret > 0)
1289                         rdev->use_count = 1;
1290                 else
1291                         rdev->use_count = 0;
1292         }
1293
1294 out:
1295         mutex_unlock(&regulator_list_mutex);
1296
1297         return regulator;
1298 }
1299
1300 /**
1301  * regulator_get - lookup and obtain a reference to a regulator.
1302  * @dev: device for regulator "consumer"
1303  * @id: Supply name or regulator ID.
1304  *
1305  * Returns a struct regulator corresponding to the regulator producer,
1306  * or IS_ERR() condition containing errno.
1307  *
1308  * Use of supply names configured via regulator_set_device_supply() is
1309  * strongly encouraged.  It is recommended that the supply name used
1310  * should match the name used for the supply and/or the relevant
1311  * device pins in the datasheet.
1312  */
1313 struct regulator *regulator_get(struct device *dev, const char *id)
1314 {
1315         return _regulator_get(dev, id, 0);
1316 }
1317 EXPORT_SYMBOL_GPL(regulator_get);
1318
1319 /**
1320  * regulator_get_exclusive - obtain exclusive access to a regulator.
1321  * @dev: device for regulator "consumer"
1322  * @id: Supply name or regulator ID.
1323  *
1324  * Returns a struct regulator corresponding to the regulator producer,
1325  * or IS_ERR() condition containing errno.  Other consumers will be
1326  * unable to obtain this reference is held and the use count for the
1327  * regulator will be initialised to reflect the current state of the
1328  * regulator.
1329  *
1330  * This is intended for use by consumers which cannot tolerate shared
1331  * use of the regulator such as those which need to force the
1332  * regulator off for correct operation of the hardware they are
1333  * controlling.
1334  *
1335  * Use of supply names configured via regulator_set_device_supply() is
1336  * strongly encouraged.  It is recommended that the supply name used
1337  * should match the name used for the supply and/or the relevant
1338  * device pins in the datasheet.
1339  */
1340 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1341 {
1342         return _regulator_get(dev, id, 1);
1343 }
1344 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1345
1346 /**
1347  * regulator_put - "free" the regulator source
1348  * @regulator: regulator source
1349  *
1350  * Note: drivers must ensure that all regulator_enable calls made on this
1351  * regulator source are balanced by regulator_disable calls prior to calling
1352  * this function.
1353  */
1354 void regulator_put(struct regulator *regulator)
1355 {
1356         struct regulator_dev *rdev;
1357
1358         if (regulator == NULL || IS_ERR(regulator))
1359                 return;
1360
1361         mutex_lock(&regulator_list_mutex);
1362         rdev = regulator->rdev;
1363
1364         debugfs_remove_recursive(regulator->debugfs);
1365
1366         /* remove any sysfs entries */
1367         if (regulator->dev) {
1368                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1369                 device_remove_file(regulator->dev, &regulator->dev_attr);
1370                 kfree(regulator->dev_attr.attr.name);
1371         }
1372         kfree(regulator->supply_name);
1373         list_del(&regulator->list);
1374         kfree(regulator);
1375
1376         rdev->open_count--;
1377         rdev->exclusive = 0;
1378
1379         module_put(rdev->owner);
1380         mutex_unlock(&regulator_list_mutex);
1381 }
1382 EXPORT_SYMBOL_GPL(regulator_put);
1383
1384 static int _regulator_can_change_status(struct regulator_dev *rdev)
1385 {
1386         if (!rdev->constraints)
1387                 return 0;
1388
1389         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1390                 return 1;
1391         else
1392                 return 0;
1393 }
1394
1395 /* locks held by regulator_enable() */
1396 static int _regulator_enable(struct regulator_dev *rdev)
1397 {
1398         int ret, delay;
1399
1400         /* check voltage and requested load before enabling */
1401         if (rdev->constraints &&
1402             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1403                 drms_uA_update(rdev);
1404
1405         if (rdev->use_count == 0) {
1406                 /* The regulator may on if it's not switchable or left on */
1407                 ret = _regulator_is_enabled(rdev);
1408                 if (ret == -EINVAL || ret == 0) {
1409                         if (!_regulator_can_change_status(rdev))
1410                                 return -EPERM;
1411
1412                         if (!rdev->desc->ops->enable)
1413                                 return -EINVAL;
1414
1415                         /* Query before enabling in case configuration
1416                          * dependent.  */
1417                         ret = _regulator_get_enable_time(rdev);
1418                         if (ret >= 0) {
1419                                 delay = ret;
1420                         } else {
1421                                 rdev_warn(rdev, "enable_time() failed: %d\n",
1422                                            ret);
1423                                 delay = 0;
1424                         }
1425
1426                         trace_regulator_enable(rdev_get_name(rdev));
1427
1428                         /* Allow the regulator to ramp; it would be useful
1429                          * to extend this for bulk operations so that the
1430                          * regulators can ramp together.  */
1431                         ret = rdev->desc->ops->enable(rdev);
1432                         if (ret < 0)
1433                                 return ret;
1434
1435                         trace_regulator_enable_delay(rdev_get_name(rdev));
1436
1437                         if (delay >= 1000) {
1438                                 mdelay(delay / 1000);
1439                                 udelay(delay % 1000);
1440                         } else if (delay) {
1441                                 udelay(delay);
1442                         }
1443
1444                         trace_regulator_enable_complete(rdev_get_name(rdev));
1445
1446                 } else if (ret < 0) {
1447                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1448                         return ret;
1449                 }
1450                 /* Fallthrough on positive return values - already enabled */
1451         }
1452
1453         rdev->use_count++;
1454
1455         return 0;
1456 }
1457
1458 /**
1459  * regulator_enable - enable regulator output
1460  * @regulator: regulator source
1461  *
1462  * Request that the regulator be enabled with the regulator output at
1463  * the predefined voltage or current value.  Calls to regulator_enable()
1464  * must be balanced with calls to regulator_disable().
1465  *
1466  * NOTE: the output value can be set by other drivers, boot loader or may be
1467  * hardwired in the regulator.
1468  */
1469 int regulator_enable(struct regulator *regulator)
1470 {
1471         struct regulator_dev *rdev = regulator->rdev;
1472         int ret = 0;
1473
1474         if (rdev->supply) {
1475                 ret = regulator_enable(rdev->supply);
1476                 if (ret != 0)
1477                         return ret;
1478         }
1479
1480         mutex_lock(&rdev->mutex);
1481         ret = _regulator_enable(rdev);
1482         mutex_unlock(&rdev->mutex);
1483
1484         if (ret != 0 && rdev->supply)
1485                 regulator_disable(rdev->supply);
1486
1487         return ret;
1488 }
1489 EXPORT_SYMBOL_GPL(regulator_enable);
1490
1491 /* locks held by regulator_disable() */
1492 static int _regulator_disable(struct regulator_dev *rdev)
1493 {
1494         int ret = 0;
1495
1496         if (WARN(rdev->use_count <= 0,
1497                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
1498                 return -EIO;
1499
1500         /* are we the last user and permitted to disable ? */
1501         if (rdev->use_count == 1 &&
1502             (rdev->constraints && !rdev->constraints->always_on)) {
1503
1504                 /* we are last user */
1505                 if (_regulator_can_change_status(rdev) &&
1506                     rdev->desc->ops->disable) {
1507                         trace_regulator_disable(rdev_get_name(rdev));
1508
1509                         ret = rdev->desc->ops->disable(rdev);
1510                         if (ret < 0) {
1511                                 rdev_err(rdev, "failed to disable\n");
1512                                 return ret;
1513                         }
1514
1515                         trace_regulator_disable_complete(rdev_get_name(rdev));
1516
1517                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1518                                              NULL);
1519                 }
1520
1521                 rdev->use_count = 0;
1522         } else if (rdev->use_count > 1) {
1523
1524                 if (rdev->constraints &&
1525                         (rdev->constraints->valid_ops_mask &
1526                         REGULATOR_CHANGE_DRMS))
1527                         drms_uA_update(rdev);
1528
1529                 rdev->use_count--;
1530         }
1531
1532         return ret;
1533 }
1534
1535 /**
1536  * regulator_disable - disable regulator output
1537  * @regulator: regulator source
1538  *
1539  * Disable the regulator output voltage or current.  Calls to
1540  * regulator_enable() must be balanced with calls to
1541  * regulator_disable().
1542  *
1543  * NOTE: this will only disable the regulator output if no other consumer
1544  * devices have it enabled, the regulator device supports disabling and
1545  * machine constraints permit this operation.
1546  */
1547 int regulator_disable(struct regulator *regulator)
1548 {
1549         struct regulator_dev *rdev = regulator->rdev;
1550         int ret = 0;
1551
1552         mutex_lock(&rdev->mutex);
1553         ret = _regulator_disable(rdev);
1554         mutex_unlock(&rdev->mutex);
1555
1556         if (ret == 0 && rdev->supply)
1557                 regulator_disable(rdev->supply);
1558
1559         return ret;
1560 }
1561 EXPORT_SYMBOL_GPL(regulator_disable);
1562
1563 /* locks held by regulator_force_disable() */
1564 static int _regulator_force_disable(struct regulator_dev *rdev)
1565 {
1566         int ret = 0;
1567
1568         /* force disable */
1569         if (rdev->desc->ops->disable) {
1570                 /* ah well, who wants to live forever... */
1571                 ret = rdev->desc->ops->disable(rdev);
1572                 if (ret < 0) {
1573                         rdev_err(rdev, "failed to force disable\n");
1574                         return ret;
1575                 }
1576                 /* notify other consumers that power has been forced off */
1577                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1578                         REGULATOR_EVENT_DISABLE, NULL);
1579         }
1580
1581         return ret;
1582 }
1583
1584 /**
1585  * regulator_force_disable - force disable regulator output
1586  * @regulator: regulator source
1587  *
1588  * Forcibly disable the regulator output voltage or current.
1589  * NOTE: this *will* disable the regulator output even if other consumer
1590  * devices have it enabled. This should be used for situations when device
1591  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1592  */
1593 int regulator_force_disable(struct regulator *regulator)
1594 {
1595         struct regulator_dev *rdev = regulator->rdev;
1596         int ret;
1597
1598         mutex_lock(&rdev->mutex);
1599         regulator->uA_load = 0;
1600         ret = _regulator_force_disable(regulator->rdev);
1601         mutex_unlock(&rdev->mutex);
1602
1603         if (rdev->supply)
1604                 while (rdev->open_count--)
1605                         regulator_disable(rdev->supply);
1606
1607         return ret;
1608 }
1609 EXPORT_SYMBOL_GPL(regulator_force_disable);
1610
1611 static void regulator_disable_work(struct work_struct *work)
1612 {
1613         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
1614                                                   disable_work.work);
1615         int count, i, ret;
1616
1617         mutex_lock(&rdev->mutex);
1618
1619         BUG_ON(!rdev->deferred_disables);
1620
1621         count = rdev->deferred_disables;
1622         rdev->deferred_disables = 0;
1623
1624         for (i = 0; i < count; i++) {
1625                 ret = _regulator_disable(rdev);
1626                 if (ret != 0)
1627                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
1628         }
1629
1630         mutex_unlock(&rdev->mutex);
1631
1632         if (rdev->supply) {
1633                 for (i = 0; i < count; i++) {
1634                         ret = regulator_disable(rdev->supply);
1635                         if (ret != 0) {
1636                                 rdev_err(rdev,
1637                                          "Supply disable failed: %d\n", ret);
1638                         }
1639                 }
1640         }
1641 }
1642
1643 /**
1644  * regulator_disable_deferred - disable regulator output with delay
1645  * @regulator: regulator source
1646  * @ms: miliseconds until the regulator is disabled
1647  *
1648  * Execute regulator_disable() on the regulator after a delay.  This
1649  * is intended for use with devices that require some time to quiesce.
1650  *
1651  * NOTE: this will only disable the regulator output if no other consumer
1652  * devices have it enabled, the regulator device supports disabling and
1653  * machine constraints permit this operation.
1654  */
1655 int regulator_disable_deferred(struct regulator *regulator, int ms)
1656 {
1657         struct regulator_dev *rdev = regulator->rdev;
1658         int ret;
1659
1660         mutex_lock(&rdev->mutex);
1661         rdev->deferred_disables++;
1662         mutex_unlock(&rdev->mutex);
1663
1664         ret = schedule_delayed_work(&rdev->disable_work,
1665                                     msecs_to_jiffies(ms));
1666         if (ret < 0)
1667                 return ret;
1668         else
1669                 return 0;
1670 }
1671 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
1672
1673 static int _regulator_is_enabled(struct regulator_dev *rdev)
1674 {
1675         /* If we don't know then assume that the regulator is always on */
1676         if (!rdev->desc->ops->is_enabled)
1677                 return 1;
1678
1679         return rdev->desc->ops->is_enabled(rdev);
1680 }
1681
1682 /**
1683  * regulator_is_enabled - is the regulator output enabled
1684  * @regulator: regulator source
1685  *
1686  * Returns positive if the regulator driver backing the source/client
1687  * has requested that the device be enabled, zero if it hasn't, else a
1688  * negative errno code.
1689  *
1690  * Note that the device backing this regulator handle can have multiple
1691  * users, so it might be enabled even if regulator_enable() was never
1692  * called for this particular source.
1693  */
1694 int regulator_is_enabled(struct regulator *regulator)
1695 {
1696         int ret;
1697
1698         mutex_lock(&regulator->rdev->mutex);
1699         ret = _regulator_is_enabled(regulator->rdev);
1700         mutex_unlock(&regulator->rdev->mutex);
1701
1702         return ret;
1703 }
1704 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1705
1706 /**
1707  * regulator_count_voltages - count regulator_list_voltage() selectors
1708  * @regulator: regulator source
1709  *
1710  * Returns number of selectors, or negative errno.  Selectors are
1711  * numbered starting at zero, and typically correspond to bitfields
1712  * in hardware registers.
1713  */
1714 int regulator_count_voltages(struct regulator *regulator)
1715 {
1716         struct regulator_dev    *rdev = regulator->rdev;
1717
1718         return rdev->desc->n_voltages ? : -EINVAL;
1719 }
1720 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1721
1722 /**
1723  * regulator_list_voltage - enumerate supported voltages
1724  * @regulator: regulator source
1725  * @selector: identify voltage to list
1726  * Context: can sleep
1727  *
1728  * Returns a voltage that can be passed to @regulator_set_voltage(),
1729  * zero if this selector code can't be used on this system, or a
1730  * negative errno.
1731  */
1732 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1733 {
1734         struct regulator_dev    *rdev = regulator->rdev;
1735         struct regulator_ops    *ops = rdev->desc->ops;
1736         int                     ret;
1737
1738         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1739                 return -EINVAL;
1740
1741         mutex_lock(&rdev->mutex);
1742         ret = ops->list_voltage(rdev, selector);
1743         mutex_unlock(&rdev->mutex);
1744
1745         if (ret > 0) {
1746                 if (ret < rdev->constraints->min_uV)
1747                         ret = 0;
1748                 else if (ret > rdev->constraints->max_uV)
1749                         ret = 0;
1750         }
1751
1752         return ret;
1753 }
1754 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1755
1756 /**
1757  * regulator_is_supported_voltage - check if a voltage range can be supported
1758  *
1759  * @regulator: Regulator to check.
1760  * @min_uV: Minimum required voltage in uV.
1761  * @max_uV: Maximum required voltage in uV.
1762  *
1763  * Returns a boolean or a negative error code.
1764  */
1765 int regulator_is_supported_voltage(struct regulator *regulator,
1766                                    int min_uV, int max_uV)
1767 {
1768         int i, voltages, ret;
1769
1770         ret = regulator_count_voltages(regulator);
1771         if (ret < 0)
1772                 return ret;
1773         voltages = ret;
1774
1775         for (i = 0; i < voltages; i++) {
1776                 ret = regulator_list_voltage(regulator, i);
1777
1778                 if (ret >= min_uV && ret <= max_uV)
1779                         return 1;
1780         }
1781
1782         return 0;
1783 }
1784 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
1785
1786 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
1787                                      int min_uV, int max_uV)
1788 {
1789         int ret;
1790         int delay = 0;
1791         unsigned int selector;
1792
1793         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
1794
1795         min_uV += rdev->constraints->uV_offset;
1796         max_uV += rdev->constraints->uV_offset;
1797
1798         if (rdev->desc->ops->set_voltage) {
1799                 ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
1800                                                    &selector);
1801
1802                 if (rdev->desc->ops->list_voltage)
1803                         selector = rdev->desc->ops->list_voltage(rdev,
1804                                                                  selector);
1805                 else
1806                         selector = -1;
1807         } else if (rdev->desc->ops->set_voltage_sel) {
1808                 int best_val = INT_MAX;
1809                 int i;
1810
1811                 selector = 0;
1812
1813                 /* Find the smallest voltage that falls within the specified
1814                  * range.
1815                  */
1816                 for (i = 0; i < rdev->desc->n_voltages; i++) {
1817                         ret = rdev->desc->ops->list_voltage(rdev, i);
1818                         if (ret < 0)
1819                                 continue;
1820
1821                         if (ret < best_val && ret >= min_uV && ret <= max_uV) {
1822                                 best_val = ret;
1823                                 selector = i;
1824                         }
1825                 }
1826
1827                 /*
1828                  * If we can't obtain the old selector there is not enough
1829                  * info to call set_voltage_time_sel().
1830                  */
1831                 if (rdev->desc->ops->set_voltage_time_sel &&
1832                     rdev->desc->ops->get_voltage_sel) {
1833                         unsigned int old_selector = 0;
1834
1835                         ret = rdev->desc->ops->get_voltage_sel(rdev);
1836                         if (ret < 0)
1837                                 return ret;
1838                         old_selector = ret;
1839                         delay = rdev->desc->ops->set_voltage_time_sel(rdev,
1840                                                 old_selector, selector);
1841                 }
1842
1843                 if (best_val != INT_MAX) {
1844                         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
1845                         selector = best_val;
1846                 } else {
1847                         ret = -EINVAL;
1848                 }
1849         } else {
1850                 ret = -EINVAL;
1851         }
1852
1853         /* Insert any necessary delays */
1854         if (delay >= 1000) {
1855                 mdelay(delay / 1000);
1856                 udelay(delay % 1000);
1857         } else if (delay) {
1858                 udelay(delay);
1859         }
1860
1861         if (ret == 0)
1862                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
1863                                      NULL);
1864
1865         trace_regulator_set_voltage_complete(rdev_get_name(rdev), selector);
1866
1867         return ret;
1868 }
1869
1870 /**
1871  * regulator_set_voltage - set regulator output voltage
1872  * @regulator: regulator source
1873  * @min_uV: Minimum required voltage in uV
1874  * @max_uV: Maximum acceptable voltage in uV
1875  *
1876  * Sets a voltage regulator to the desired output voltage. This can be set
1877  * during any regulator state. IOW, regulator can be disabled or enabled.
1878  *
1879  * If the regulator is enabled then the voltage will change to the new value
1880  * immediately otherwise if the regulator is disabled the regulator will
1881  * output at the new voltage when enabled.
1882  *
1883  * NOTE: If the regulator is shared between several devices then the lowest
1884  * request voltage that meets the system constraints will be used.
1885  * Regulator system constraints must be set for this regulator before
1886  * calling this function otherwise this call will fail.
1887  */
1888 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1889 {
1890         struct regulator_dev *rdev = regulator->rdev;
1891         int ret = 0;
1892
1893         mutex_lock(&rdev->mutex);
1894
1895         /* If we're setting the same range as last time the change
1896          * should be a noop (some cpufreq implementations use the same
1897          * voltage for multiple frequencies, for example).
1898          */
1899         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
1900                 goto out;
1901
1902         /* sanity check */
1903         if (!rdev->desc->ops->set_voltage &&
1904             !rdev->desc->ops->set_voltage_sel) {
1905                 ret = -EINVAL;
1906                 goto out;
1907         }
1908
1909         /* constraints check */
1910         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1911         if (ret < 0)
1912                 goto out;
1913         regulator->min_uV = min_uV;
1914         regulator->max_uV = max_uV;
1915
1916         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
1917         if (ret < 0)
1918                 goto out;
1919
1920         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
1921
1922 out:
1923         mutex_unlock(&rdev->mutex);
1924         return ret;
1925 }
1926 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1927
1928 /**
1929  * regulator_set_voltage_time - get raise/fall time
1930  * @regulator: regulator source
1931  * @old_uV: starting voltage in microvolts
1932  * @new_uV: target voltage in microvolts
1933  *
1934  * Provided with the starting and ending voltage, this function attempts to
1935  * calculate the time in microseconds required to rise or fall to this new
1936  * voltage.
1937  */
1938 int regulator_set_voltage_time(struct regulator *regulator,
1939                                int old_uV, int new_uV)
1940 {
1941         struct regulator_dev    *rdev = regulator->rdev;
1942         struct regulator_ops    *ops = rdev->desc->ops;
1943         int old_sel = -1;
1944         int new_sel = -1;
1945         int voltage;
1946         int i;
1947
1948         /* Currently requires operations to do this */
1949         if (!ops->list_voltage || !ops->set_voltage_time_sel
1950             || !rdev->desc->n_voltages)
1951                 return -EINVAL;
1952
1953         for (i = 0; i < rdev->desc->n_voltages; i++) {
1954                 /* We only look for exact voltage matches here */
1955                 voltage = regulator_list_voltage(regulator, i);
1956                 if (voltage < 0)
1957                         return -EINVAL;
1958                 if (voltage == 0)
1959                         continue;
1960                 if (voltage == old_uV)
1961                         old_sel = i;
1962                 if (voltage == new_uV)
1963                         new_sel = i;
1964         }
1965
1966         if (old_sel < 0 || new_sel < 0)
1967                 return -EINVAL;
1968
1969         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
1970 }
1971 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
1972
1973 /**
1974  * regulator_sync_voltage - re-apply last regulator output voltage
1975  * @regulator: regulator source
1976  *
1977  * Re-apply the last configured voltage.  This is intended to be used
1978  * where some external control source the consumer is cooperating with
1979  * has caused the configured voltage to change.
1980  */
1981 int regulator_sync_voltage(struct regulator *regulator)
1982 {
1983         struct regulator_dev *rdev = regulator->rdev;
1984         int ret, min_uV, max_uV;
1985
1986         mutex_lock(&rdev->mutex);
1987
1988         if (!rdev->desc->ops->set_voltage &&
1989             !rdev->desc->ops->set_voltage_sel) {
1990                 ret = -EINVAL;
1991                 goto out;
1992         }
1993
1994         /* This is only going to work if we've had a voltage configured. */
1995         if (!regulator->min_uV && !regulator->max_uV) {
1996                 ret = -EINVAL;
1997                 goto out;
1998         }
1999
2000         min_uV = regulator->min_uV;
2001         max_uV = regulator->max_uV;
2002
2003         /* This should be a paranoia check... */
2004         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2005         if (ret < 0)
2006                 goto out;
2007
2008         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2009         if (ret < 0)
2010                 goto out;
2011
2012         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2013
2014 out:
2015         mutex_unlock(&rdev->mutex);
2016         return ret;
2017 }
2018 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2019
2020 static int _regulator_get_voltage(struct regulator_dev *rdev)
2021 {
2022         int sel, ret;
2023
2024         if (rdev->desc->ops->get_voltage_sel) {
2025                 sel = rdev->desc->ops->get_voltage_sel(rdev);
2026                 if (sel < 0)
2027                         return sel;
2028                 ret = rdev->desc->ops->list_voltage(rdev, sel);
2029         } else if (rdev->desc->ops->get_voltage) {
2030                 ret = rdev->desc->ops->get_voltage(rdev);
2031         } else {
2032                 return -EINVAL;
2033         }
2034
2035         if (ret < 0)
2036                 return ret;
2037         return ret - rdev->constraints->uV_offset;
2038 }
2039
2040 /**
2041  * regulator_get_voltage - get regulator output voltage
2042  * @regulator: regulator source
2043  *
2044  * This returns the current regulator voltage in uV.
2045  *
2046  * NOTE: If the regulator is disabled it will return the voltage value. This
2047  * function should not be used to determine regulator state.
2048  */
2049 int regulator_get_voltage(struct regulator *regulator)
2050 {
2051         int ret;
2052
2053         mutex_lock(&regulator->rdev->mutex);
2054
2055         ret = _regulator_get_voltage(regulator->rdev);
2056
2057         mutex_unlock(&regulator->rdev->mutex);
2058
2059         return ret;
2060 }
2061 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2062
2063 /**
2064  * regulator_set_current_limit - set regulator output current limit
2065  * @regulator: regulator source
2066  * @min_uA: Minimuum supported current in uA
2067  * @max_uA: Maximum supported current in uA
2068  *
2069  * Sets current sink to the desired output current. This can be set during
2070  * any regulator state. IOW, regulator can be disabled or enabled.
2071  *
2072  * If the regulator is enabled then the current will change to the new value
2073  * immediately otherwise if the regulator is disabled the regulator will
2074  * output at the new current when enabled.
2075  *
2076  * NOTE: Regulator system constraints must be set for this regulator before
2077  * calling this function otherwise this call will fail.
2078  */
2079 int regulator_set_current_limit(struct regulator *regulator,
2080                                int min_uA, int max_uA)
2081 {
2082         struct regulator_dev *rdev = regulator->rdev;
2083         int ret;
2084
2085         mutex_lock(&rdev->mutex);
2086
2087         /* sanity check */
2088         if (!rdev->desc->ops->set_current_limit) {
2089                 ret = -EINVAL;
2090                 goto out;
2091         }
2092
2093         /* constraints check */
2094         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2095         if (ret < 0)
2096                 goto out;
2097
2098         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2099 out:
2100         mutex_unlock(&rdev->mutex);
2101         return ret;
2102 }
2103 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2104
2105 static int _regulator_get_current_limit(struct regulator_dev *rdev)
2106 {
2107         int ret;
2108
2109         mutex_lock(&rdev->mutex);
2110
2111         /* sanity check */
2112         if (!rdev->desc->ops->get_current_limit) {
2113                 ret = -EINVAL;
2114                 goto out;
2115         }
2116
2117         ret = rdev->desc->ops->get_current_limit(rdev);
2118 out:
2119         mutex_unlock(&rdev->mutex);
2120         return ret;
2121 }
2122
2123 /**
2124  * regulator_get_current_limit - get regulator output current
2125  * @regulator: regulator source
2126  *
2127  * This returns the current supplied by the specified current sink in uA.
2128  *
2129  * NOTE: If the regulator is disabled it will return the current value. This
2130  * function should not be used to determine regulator state.
2131  */
2132 int regulator_get_current_limit(struct regulator *regulator)
2133 {
2134         return _regulator_get_current_limit(regulator->rdev);
2135 }
2136 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
2137
2138 /**
2139  * regulator_set_mode - set regulator operating mode
2140  * @regulator: regulator source
2141  * @mode: operating mode - one of the REGULATOR_MODE constants
2142  *
2143  * Set regulator operating mode to increase regulator efficiency or improve
2144  * regulation performance.
2145  *
2146  * NOTE: Regulator system constraints must be set for this regulator before
2147  * calling this function otherwise this call will fail.
2148  */
2149 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2150 {
2151         struct regulator_dev *rdev = regulator->rdev;
2152         int ret;
2153         int regulator_curr_mode;
2154
2155         mutex_lock(&rdev->mutex);
2156
2157         /* sanity check */
2158         if (!rdev->desc->ops->set_mode) {
2159                 ret = -EINVAL;
2160                 goto out;
2161         }
2162
2163         /* return if the same mode is requested */
2164         if (rdev->desc->ops->get_mode) {
2165                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2166                 if (regulator_curr_mode == mode) {
2167                         ret = 0;
2168                         goto out;
2169                 }
2170         }
2171
2172         /* constraints check */
2173         ret = regulator_mode_constrain(rdev, &mode);
2174         if (ret < 0)
2175                 goto out;
2176
2177         ret = rdev->desc->ops->set_mode(rdev, mode);
2178 out:
2179         mutex_unlock(&rdev->mutex);
2180         return ret;
2181 }
2182 EXPORT_SYMBOL_GPL(regulator_set_mode);
2183
2184 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2185 {
2186         int ret;
2187
2188         mutex_lock(&rdev->mutex);
2189
2190         /* sanity check */
2191         if (!rdev->desc->ops->get_mode) {
2192                 ret = -EINVAL;
2193                 goto out;
2194         }
2195
2196         ret = rdev->desc->ops->get_mode(rdev);
2197 out:
2198         mutex_unlock(&rdev->mutex);
2199         return ret;
2200 }
2201
2202 /**
2203  * regulator_get_mode - get regulator operating mode
2204  * @regulator: regulator source
2205  *
2206  * Get the current regulator operating mode.
2207  */
2208 unsigned int regulator_get_mode(struct regulator *regulator)
2209 {
2210         return _regulator_get_mode(regulator->rdev);
2211 }
2212 EXPORT_SYMBOL_GPL(regulator_get_mode);
2213
2214 /**
2215  * regulator_set_optimum_mode - set regulator optimum operating mode
2216  * @regulator: regulator source
2217  * @uA_load: load current
2218  *
2219  * Notifies the regulator core of a new device load. This is then used by
2220  * DRMS (if enabled by constraints) to set the most efficient regulator
2221  * operating mode for the new regulator loading.
2222  *
2223  * Consumer devices notify their supply regulator of the maximum power
2224  * they will require (can be taken from device datasheet in the power
2225  * consumption tables) when they change operational status and hence power
2226  * state. Examples of operational state changes that can affect power
2227  * consumption are :-
2228  *
2229  *    o Device is opened / closed.
2230  *    o Device I/O is about to begin or has just finished.
2231  *    o Device is idling in between work.
2232  *
2233  * This information is also exported via sysfs to userspace.
2234  *
2235  * DRMS will sum the total requested load on the regulator and change
2236  * to the most efficient operating mode if platform constraints allow.
2237  *
2238  * Returns the new regulator mode or error.
2239  */
2240 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
2241 {
2242         struct regulator_dev *rdev = regulator->rdev;
2243         struct regulator *consumer;
2244         int ret, output_uV, input_uV, total_uA_load = 0;
2245         unsigned int mode;
2246
2247         mutex_lock(&rdev->mutex);
2248
2249         /*
2250          * first check to see if we can set modes at all, otherwise just
2251          * tell the consumer everything is OK.
2252          */
2253         regulator->uA_load = uA_load;
2254         ret = regulator_check_drms(rdev);
2255         if (ret < 0) {
2256                 ret = 0;
2257                 goto out;
2258         }
2259
2260         if (!rdev->desc->ops->get_optimum_mode)
2261                 goto out;
2262
2263         /*
2264          * we can actually do this so any errors are indicators of
2265          * potential real failure.
2266          */
2267         ret = -EINVAL;
2268
2269         /* get output voltage */
2270         output_uV = _regulator_get_voltage(rdev);
2271         if (output_uV <= 0) {
2272                 rdev_err(rdev, "invalid output voltage found\n");
2273                 goto out;
2274         }
2275
2276         /* get input voltage */
2277         input_uV = 0;
2278         if (rdev->supply)
2279                 input_uV = regulator_get_voltage(rdev->supply);
2280         if (input_uV <= 0)
2281                 input_uV = rdev->constraints->input_uV;
2282         if (input_uV <= 0) {
2283                 rdev_err(rdev, "invalid input voltage found\n");
2284                 goto out;
2285         }
2286
2287         /* calc total requested load for this regulator */
2288         list_for_each_entry(consumer, &rdev->consumer_list, list)
2289                 total_uA_load += consumer->uA_load;
2290
2291         mode = rdev->desc->ops->get_optimum_mode(rdev,
2292                                                  input_uV, output_uV,
2293                                                  total_uA_load);
2294         ret = regulator_mode_constrain(rdev, &mode);
2295         if (ret < 0) {
2296                 rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
2297                          total_uA_load, input_uV, output_uV);
2298                 goto out;
2299         }
2300
2301         ret = rdev->desc->ops->set_mode(rdev, mode);
2302         if (ret < 0) {
2303                 rdev_err(rdev, "failed to set optimum mode %x\n", mode);
2304                 goto out;
2305         }
2306         ret = mode;
2307 out:
2308         mutex_unlock(&rdev->mutex);
2309         return ret;
2310 }
2311 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
2312
2313 /**
2314  * regulator_register_notifier - register regulator event notifier
2315  * @regulator: regulator source
2316  * @nb: notifier block
2317  *
2318  * Register notifier block to receive regulator events.
2319  */
2320 int regulator_register_notifier(struct regulator *regulator,
2321                               struct notifier_block *nb)
2322 {
2323         return blocking_notifier_chain_register(&regulator->rdev->notifier,
2324                                                 nb);
2325 }
2326 EXPORT_SYMBOL_GPL(regulator_register_notifier);
2327
2328 /**
2329  * regulator_unregister_notifier - unregister regulator event notifier
2330  * @regulator: regulator source
2331  * @nb: notifier block
2332  *
2333  * Unregister regulator event notifier block.
2334  */
2335 int regulator_unregister_notifier(struct regulator *regulator,
2336                                 struct notifier_block *nb)
2337 {
2338         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
2339                                                   nb);
2340 }
2341 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
2342
2343 /* notify regulator consumers and downstream regulator consumers.
2344  * Note mutex must be held by caller.
2345  */
2346 static void _notifier_call_chain(struct regulator_dev *rdev,
2347                                   unsigned long event, void *data)
2348 {
2349         /* call rdev chain first */
2350         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
2351 }
2352
2353 /**
2354  * regulator_bulk_get - get multiple regulator consumers
2355  *
2356  * @dev:           Device to supply
2357  * @num_consumers: Number of consumers to register
2358  * @consumers:     Configuration of consumers; clients are stored here.
2359  *
2360  * @return 0 on success, an errno on failure.
2361  *
2362  * This helper function allows drivers to get several regulator
2363  * consumers in one operation.  If any of the regulators cannot be
2364  * acquired then any regulators that were allocated will be freed
2365  * before returning to the caller.
2366  */
2367 int regulator_bulk_get(struct device *dev, int num_consumers,
2368                        struct regulator_bulk_data *consumers)
2369 {
2370         int i;
2371         int ret;
2372
2373         for (i = 0; i < num_consumers; i++)
2374                 consumers[i].consumer = NULL;
2375
2376         for (i = 0; i < num_consumers; i++) {
2377                 consumers[i].consumer = regulator_get(dev,
2378                                                       consumers[i].supply);
2379                 if (IS_ERR(consumers[i].consumer)) {
2380                         ret = PTR_ERR(consumers[i].consumer);
2381                         dev_err(dev, "Failed to get supply '%s': %d\n",
2382                                 consumers[i].supply, ret);
2383                         consumers[i].consumer = NULL;
2384                         goto err;
2385                 }
2386         }
2387
2388         return 0;
2389
2390 err:
2391         while (--i >= 0)
2392                 regulator_put(consumers[i].consumer);
2393
2394         return ret;
2395 }
2396 EXPORT_SYMBOL_GPL(regulator_bulk_get);
2397
2398 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
2399 {
2400         struct regulator_bulk_data *bulk = data;
2401
2402         bulk->ret = regulator_enable(bulk->consumer);
2403 }
2404
2405 /**
2406  * regulator_bulk_enable - enable multiple regulator consumers
2407  *
2408  * @num_consumers: Number of consumers
2409  * @consumers:     Consumer data; clients are stored here.
2410  * @return         0 on success, an errno on failure
2411  *
2412  * This convenience API allows consumers to enable multiple regulator
2413  * clients in a single API call.  If any consumers cannot be enabled
2414  * then any others that were enabled will be disabled again prior to
2415  * return.
2416  */
2417 int regulator_bulk_enable(int num_consumers,
2418                           struct regulator_bulk_data *consumers)
2419 {
2420         LIST_HEAD(async_domain);
2421         int i;
2422         int ret = 0;
2423
2424         for (i = 0; i < num_consumers; i++)
2425                 async_schedule_domain(regulator_bulk_enable_async,
2426                                       &consumers[i], &async_domain);
2427
2428         async_synchronize_full_domain(&async_domain);
2429
2430         /* If any consumer failed we need to unwind any that succeeded */
2431         for (i = 0; i < num_consumers; i++) {
2432                 if (consumers[i].ret != 0) {
2433                         ret = consumers[i].ret;
2434                         goto err;
2435                 }
2436         }
2437
2438         return 0;
2439
2440 err:
2441         pr_err("Failed to enable %s: %d\n", consumers[i].supply, ret);
2442         while (--i >= 0)
2443                 regulator_disable(consumers[i].consumer);
2444
2445         return ret;
2446 }
2447 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2448
2449 /**
2450  * regulator_bulk_disable - disable multiple regulator consumers
2451  *
2452  * @num_consumers: Number of consumers
2453  * @consumers:     Consumer data; clients are stored here.
2454  * @return         0 on success, an errno on failure
2455  *
2456  * This convenience API allows consumers to disable multiple regulator
2457  * clients in a single API call.  If any consumers cannot be disabled
2458  * then any others that were disabled will be enabled again prior to
2459  * return.
2460  */
2461 int regulator_bulk_disable(int num_consumers,
2462                            struct regulator_bulk_data *consumers)
2463 {
2464         int i;
2465         int ret;
2466
2467         for (i = num_consumers - 1; i >= 0; --i) {
2468                 ret = regulator_disable(consumers[i].consumer);
2469                 if (ret != 0)
2470                         goto err;
2471         }
2472
2473         return 0;
2474
2475 err:
2476         pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
2477         for (++i; i < num_consumers; ++i)
2478                 regulator_enable(consumers[i].consumer);
2479
2480         return ret;
2481 }
2482 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2483
2484 /**
2485  * regulator_bulk_force_disable - force disable multiple regulator consumers
2486  *
2487  * @num_consumers: Number of consumers
2488  * @consumers:     Consumer data; clients are stored here.
2489  * @return         0 on success, an errno on failure
2490  *
2491  * This convenience API allows consumers to forcibly disable multiple regulator
2492  * clients in a single API call.
2493  * NOTE: This should be used for situations when device damage will
2494  * likely occur if the regulators are not disabled (e.g. over temp).
2495  * Although regulator_force_disable function call for some consumers can
2496  * return error numbers, the function is called for all consumers.
2497  */
2498 int regulator_bulk_force_disable(int num_consumers,
2499                            struct regulator_bulk_data *consumers)
2500 {
2501         int i;
2502         int ret;
2503
2504         for (i = 0; i < num_consumers; i++)
2505                 consumers[i].ret =
2506                             regulator_force_disable(consumers[i].consumer);
2507
2508         for (i = 0; i < num_consumers; i++) {
2509                 if (consumers[i].ret != 0) {
2510                         ret = consumers[i].ret;
2511                         goto out;
2512                 }
2513         }
2514
2515         return 0;
2516 out:
2517         return ret;
2518 }
2519 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
2520
2521 /**
2522  * regulator_bulk_free - free multiple regulator consumers
2523  *
2524  * @num_consumers: Number of consumers
2525  * @consumers:     Consumer data; clients are stored here.
2526  *
2527  * This convenience API allows consumers to free multiple regulator
2528  * clients in a single API call.
2529  */
2530 void regulator_bulk_free(int num_consumers,
2531                          struct regulator_bulk_data *consumers)
2532 {
2533         int i;
2534
2535         for (i = 0; i < num_consumers; i++) {
2536                 regulator_put(consumers[i].consumer);
2537                 consumers[i].consumer = NULL;
2538         }
2539 }
2540 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2541
2542 /**
2543  * regulator_notifier_call_chain - call regulator event notifier
2544  * @rdev: regulator source
2545  * @event: notifier block
2546  * @data: callback-specific data.
2547  *
2548  * Called by regulator drivers to notify clients a regulator event has
2549  * occurred. We also notify regulator clients downstream.
2550  * Note lock must be held by caller.
2551  */
2552 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2553                                   unsigned long event, void *data)
2554 {
2555         _notifier_call_chain(rdev, event, data);
2556         return NOTIFY_DONE;
2557
2558 }
2559 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2560
2561 /**
2562  * regulator_mode_to_status - convert a regulator mode into a status
2563  *
2564  * @mode: Mode to convert
2565  *
2566  * Convert a regulator mode into a status.
2567  */
2568 int regulator_mode_to_status(unsigned int mode)
2569 {
2570         switch (mode) {
2571         case REGULATOR_MODE_FAST:
2572                 return REGULATOR_STATUS_FAST;
2573         case REGULATOR_MODE_NORMAL:
2574                 return REGULATOR_STATUS_NORMAL;
2575         case REGULATOR_MODE_IDLE:
2576                 return REGULATOR_STATUS_IDLE;
2577         case REGULATOR_STATUS_STANDBY:
2578                 return REGULATOR_STATUS_STANDBY;
2579         default:
2580                 return 0;
2581         }
2582 }
2583 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2584
2585 /*
2586  * To avoid cluttering sysfs (and memory) with useless state, only
2587  * create attributes that can be meaningfully displayed.
2588  */
2589 static int add_regulator_attributes(struct regulator_dev *rdev)
2590 {
2591         struct device           *dev = &rdev->dev;
2592         struct regulator_ops    *ops = rdev->desc->ops;
2593         int                     status = 0;
2594
2595         /* some attributes need specific methods to be displayed */
2596         if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
2597             (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0)) {
2598                 status = device_create_file(dev, &dev_attr_microvolts);
2599                 if (status < 0)
2600                         return status;
2601         }
2602         if (ops->get_current_limit) {
2603                 status = device_create_file(dev, &dev_attr_microamps);
2604                 if (status < 0)
2605                         return status;
2606         }
2607         if (ops->get_mode) {
2608                 status = device_create_file(dev, &dev_attr_opmode);
2609                 if (status < 0)
2610                         return status;
2611         }
2612         if (ops->is_enabled) {
2613                 status = device_create_file(dev, &dev_attr_state);
2614                 if (status < 0)
2615                         return status;
2616         }
2617         if (ops->get_status) {
2618                 status = device_create_file(dev, &dev_attr_status);
2619                 if (status < 0)
2620                         return status;
2621         }
2622
2623         /* some attributes are type-specific */
2624         if (rdev->desc->type == REGULATOR_CURRENT) {
2625                 status = device_create_file(dev, &dev_attr_requested_microamps);
2626                 if (status < 0)
2627                         return status;
2628         }
2629
2630         /* all the other attributes exist to support constraints;
2631          * don't show them if there are no constraints, or if the
2632          * relevant supporting methods are missing.
2633          */
2634         if (!rdev->constraints)
2635                 return status;
2636
2637         /* constraints need specific supporting methods */
2638         if (ops->set_voltage || ops->set_voltage_sel) {
2639                 status = device_create_file(dev, &dev_attr_min_microvolts);
2640                 if (status < 0)
2641                         return status;
2642                 status = device_create_file(dev, &dev_attr_max_microvolts);
2643                 if (status < 0)
2644                         return status;
2645         }
2646         if (ops->set_current_limit) {
2647                 status = device_create_file(dev, &dev_attr_min_microamps);
2648                 if (status < 0)
2649                         return status;
2650                 status = device_create_file(dev, &dev_attr_max_microamps);
2651                 if (status < 0)
2652                         return status;
2653         }
2654
2655         /* suspend mode constraints need multiple supporting methods */
2656         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2657                 return status;
2658
2659         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2660         if (status < 0)
2661                 return status;
2662         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2663         if (status < 0)
2664                 return status;
2665         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2666         if (status < 0)
2667                 return status;
2668
2669         if (ops->set_suspend_voltage) {
2670                 status = device_create_file(dev,
2671                                 &dev_attr_suspend_standby_microvolts);
2672                 if (status < 0)
2673                         return status;
2674                 status = device_create_file(dev,
2675                                 &dev_attr_suspend_mem_microvolts);
2676                 if (status < 0)
2677                         return status;
2678                 status = device_create_file(dev,
2679                                 &dev_attr_suspend_disk_microvolts);
2680                 if (status < 0)
2681                         return status;
2682         }
2683
2684         if (ops->set_suspend_mode) {
2685                 status = device_create_file(dev,
2686                                 &dev_attr_suspend_standby_mode);
2687                 if (status < 0)
2688                         return status;
2689                 status = device_create_file(dev,
2690                                 &dev_attr_suspend_mem_mode);
2691                 if (status < 0)
2692                         return status;
2693                 status = device_create_file(dev,
2694                                 &dev_attr_suspend_disk_mode);
2695                 if (status < 0)
2696                         return status;
2697         }
2698
2699         return status;
2700 }
2701
2702 static void rdev_init_debugfs(struct regulator_dev *rdev)
2703 {
2704         rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
2705         if (!rdev->debugfs) {
2706                 rdev_warn(rdev, "Failed to create debugfs directory\n");
2707                 return;
2708         }
2709
2710         debugfs_create_u32("use_count", 0444, rdev->debugfs,
2711                            &rdev->use_count);
2712         debugfs_create_u32("open_count", 0444, rdev->debugfs,
2713                            &rdev->open_count);
2714 }
2715
2716 /**
2717  * regulator_register - register regulator
2718  * @regulator_desc: regulator to register
2719  * @dev: struct device for the regulator
2720  * @init_data: platform provided init data, passed through by driver
2721  * @driver_data: private regulator data
2722  *
2723  * Called by regulator drivers to register a regulator.
2724  * Returns 0 on success.
2725  */
2726 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2727         struct device *dev, const struct regulator_init_data *init_data,
2728         void *driver_data, struct device_node *of_node)
2729 {
2730         const struct regulation_constraints *constraints = NULL;
2731         static atomic_t regulator_no = ATOMIC_INIT(0);
2732         struct regulator_dev *rdev;
2733         int ret, i;
2734         const char *supply = NULL;
2735
2736         if (regulator_desc == NULL)
2737                 return ERR_PTR(-EINVAL);
2738
2739         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2740                 return ERR_PTR(-EINVAL);
2741
2742         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2743             regulator_desc->type != REGULATOR_CURRENT)
2744                 return ERR_PTR(-EINVAL);
2745
2746         /* Only one of each should be implemented */
2747         WARN_ON(regulator_desc->ops->get_voltage &&
2748                 regulator_desc->ops->get_voltage_sel);
2749         WARN_ON(regulator_desc->ops->set_voltage &&
2750                 regulator_desc->ops->set_voltage_sel);
2751
2752         /* If we're using selectors we must implement list_voltage. */
2753         if (regulator_desc->ops->get_voltage_sel &&
2754             !regulator_desc->ops->list_voltage) {
2755                 return ERR_PTR(-EINVAL);
2756         }
2757         if (regulator_desc->ops->set_voltage_sel &&
2758             !regulator_desc->ops->list_voltage) {
2759                 return ERR_PTR(-EINVAL);
2760         }
2761
2762         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2763         if (rdev == NULL)
2764                 return ERR_PTR(-ENOMEM);
2765
2766         mutex_lock(&regulator_list_mutex);
2767
2768         mutex_init(&rdev->mutex);
2769         rdev->reg_data = driver_data;
2770         rdev->owner = regulator_desc->owner;
2771         rdev->desc = regulator_desc;
2772         INIT_LIST_HEAD(&rdev->consumer_list);
2773         INIT_LIST_HEAD(&rdev->list);
2774         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2775         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
2776
2777         /* preform any regulator specific init */
2778         if (init_data && init_data->regulator_init) {
2779                 ret = init_data->regulator_init(rdev->reg_data);
2780                 if (ret < 0)
2781                         goto clean;
2782         }
2783
2784         /* register with sysfs */
2785         rdev->dev.class = &regulator_class;
2786         rdev->dev.of_node = of_node;
2787         rdev->dev.parent = dev;
2788         dev_set_name(&rdev->dev, "regulator.%d",
2789                      atomic_inc_return(&regulator_no) - 1);
2790         ret = device_register(&rdev->dev);
2791         if (ret != 0) {
2792                 put_device(&rdev->dev);
2793                 goto clean;
2794         }
2795
2796         dev_set_drvdata(&rdev->dev, rdev);
2797
2798         /* set regulator constraints */
2799         if (init_data)
2800                 constraints = &init_data->constraints;
2801
2802         ret = set_machine_constraints(rdev, constraints);
2803         if (ret < 0)
2804                 goto scrub;
2805
2806         /* add attributes supported by this regulator */
2807         ret = add_regulator_attributes(rdev);
2808         if (ret < 0)
2809                 goto scrub;
2810
2811         if (init_data && init_data->supply_regulator)
2812                 supply = init_data->supply_regulator;
2813         else if (regulator_desc->supply_name)
2814                 supply = regulator_desc->supply_name;
2815
2816         if (supply) {
2817                 struct regulator_dev *r;
2818
2819                 r = regulator_dev_lookup(dev, supply);
2820
2821                 if (!r) {
2822                         dev_err(dev, "Failed to find supply %s\n", supply);
2823                         ret = -ENODEV;
2824                         goto scrub;
2825                 }
2826
2827                 ret = set_supply(rdev, r);
2828                 if (ret < 0)
2829                         goto scrub;
2830
2831                 /* Enable supply if rail is enabled */
2832                 if (rdev->desc->ops->is_enabled &&
2833                                 rdev->desc->ops->is_enabled(rdev)) {
2834                         ret = regulator_enable(rdev->supply);
2835                         if (ret < 0)
2836                                 goto scrub;
2837                 }
2838         }
2839
2840         /* add consumers devices */
2841         if (init_data) {
2842                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
2843                         ret = set_consumer_device_supply(rdev,
2844                                 init_data->consumer_supplies[i].dev,
2845                                 init_data->consumer_supplies[i].dev_name,
2846                                 init_data->consumer_supplies[i].supply);
2847                         if (ret < 0) {
2848                                 dev_err(dev, "Failed to set supply %s\n",
2849                                         init_data->consumer_supplies[i].supply);
2850                                 goto unset_supplies;
2851                         }
2852                 }
2853         }
2854
2855         list_add(&rdev->list, &regulator_list);
2856
2857         rdev_init_debugfs(rdev);
2858 out:
2859         mutex_unlock(&regulator_list_mutex);
2860         return rdev;
2861
2862 unset_supplies:
2863         unset_regulator_supplies(rdev);
2864
2865 scrub:
2866         kfree(rdev->constraints);
2867         device_unregister(&rdev->dev);
2868         /* device core frees rdev */
2869         rdev = ERR_PTR(ret);
2870         goto out;
2871
2872 clean:
2873         kfree(rdev);
2874         rdev = ERR_PTR(ret);
2875         goto out;
2876 }
2877 EXPORT_SYMBOL_GPL(regulator_register);
2878
2879 /**
2880  * regulator_unregister - unregister regulator
2881  * @rdev: regulator to unregister
2882  *
2883  * Called by regulator drivers to unregister a regulator.
2884  */
2885 void regulator_unregister(struct regulator_dev *rdev)
2886 {
2887         if (rdev == NULL)
2888                 return;
2889
2890         mutex_lock(&regulator_list_mutex);
2891         debugfs_remove_recursive(rdev->debugfs);
2892         flush_work_sync(&rdev->disable_work.work);
2893         WARN_ON(rdev->open_count);
2894         unset_regulator_supplies(rdev);
2895         list_del(&rdev->list);
2896         if (rdev->supply)
2897                 regulator_put(rdev->supply);
2898         kfree(rdev->constraints);
2899         device_unregister(&rdev->dev);
2900         mutex_unlock(&regulator_list_mutex);
2901 }
2902 EXPORT_SYMBOL_GPL(regulator_unregister);
2903
2904 /**
2905  * regulator_suspend_prepare - prepare regulators for system wide suspend
2906  * @state: system suspend state
2907  *
2908  * Configure each regulator with it's suspend operating parameters for state.
2909  * This will usually be called by machine suspend code prior to supending.
2910  */
2911 int regulator_suspend_prepare(suspend_state_t state)
2912 {
2913         struct regulator_dev *rdev;
2914         int ret = 0;
2915
2916         /* ON is handled by regulator active state */
2917         if (state == PM_SUSPEND_ON)
2918                 return -EINVAL;
2919
2920         mutex_lock(&regulator_list_mutex);
2921         list_for_each_entry(rdev, &regulator_list, list) {
2922
2923                 mutex_lock(&rdev->mutex);
2924                 ret = suspend_prepare(rdev, state);
2925                 mutex_unlock(&rdev->mutex);
2926
2927                 if (ret < 0) {
2928                         rdev_err(rdev, "failed to prepare\n");
2929                         goto out;
2930                 }
2931         }
2932 out:
2933         mutex_unlock(&regulator_list_mutex);
2934         return ret;
2935 }
2936 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2937
2938 /**
2939  * regulator_suspend_finish - resume regulators from system wide suspend
2940  *
2941  * Turn on regulators that might be turned off by regulator_suspend_prepare
2942  * and that should be turned on according to the regulators properties.
2943  */
2944 int regulator_suspend_finish(void)
2945 {
2946         struct regulator_dev *rdev;
2947         int ret = 0, error;
2948
2949         mutex_lock(&regulator_list_mutex);
2950         list_for_each_entry(rdev, &regulator_list, list) {
2951                 struct regulator_ops *ops = rdev->desc->ops;
2952
2953                 mutex_lock(&rdev->mutex);
2954                 if ((rdev->use_count > 0  || rdev->constraints->always_on) &&
2955                                 ops->enable) {
2956                         error = ops->enable(rdev);
2957                         if (error)
2958                                 ret = error;
2959                 } else {
2960                         if (!has_full_constraints)
2961                                 goto unlock;
2962                         if (!ops->disable)
2963                                 goto unlock;
2964                         if (ops->is_enabled && !ops->is_enabled(rdev))
2965                                 goto unlock;
2966
2967                         error = ops->disable(rdev);
2968                         if (error)
2969                                 ret = error;
2970                 }
2971 unlock:
2972                 mutex_unlock(&rdev->mutex);
2973         }
2974         mutex_unlock(&regulator_list_mutex);
2975         return ret;
2976 }
2977 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
2978
2979 /**
2980  * regulator_has_full_constraints - the system has fully specified constraints
2981  *
2982  * Calling this function will cause the regulator API to disable all
2983  * regulators which have a zero use count and don't have an always_on
2984  * constraint in a late_initcall.
2985  *
2986  * The intention is that this will become the default behaviour in a
2987  * future kernel release so users are encouraged to use this facility
2988  * now.
2989  */
2990 void regulator_has_full_constraints(void)
2991 {
2992         has_full_constraints = 1;
2993 }
2994 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2995
2996 /**
2997  * regulator_use_dummy_regulator - Provide a dummy regulator when none is found
2998  *
2999  * Calling this function will cause the regulator API to provide a
3000  * dummy regulator to consumers if no physical regulator is found,
3001  * allowing most consumers to proceed as though a regulator were
3002  * configured.  This allows systems such as those with software
3003  * controllable regulators for the CPU core only to be brought up more
3004  * readily.
3005  */
3006 void regulator_use_dummy_regulator(void)
3007 {
3008         board_wants_dummy_regulator = true;
3009 }
3010 EXPORT_SYMBOL_GPL(regulator_use_dummy_regulator);
3011
3012 /**
3013  * rdev_get_drvdata - get rdev regulator driver data
3014  * @rdev: regulator
3015  *
3016  * Get rdev regulator driver private data. This call can be used in the
3017  * regulator driver context.
3018  */
3019 void *rdev_get_drvdata(struct regulator_dev *rdev)
3020 {
3021         return rdev->reg_data;
3022 }
3023 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3024
3025 /**
3026  * regulator_get_drvdata - get regulator driver data
3027  * @regulator: regulator
3028  *
3029  * Get regulator driver private data. This call can be used in the consumer
3030  * driver context when non API regulator specific functions need to be called.
3031  */
3032 void *regulator_get_drvdata(struct regulator *regulator)
3033 {
3034         return regulator->rdev->reg_data;
3035 }
3036 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3037
3038 /**
3039  * regulator_set_drvdata - set regulator driver data
3040  * @regulator: regulator
3041  * @data: data
3042  */
3043 void regulator_set_drvdata(struct regulator *regulator, void *data)
3044 {
3045         regulator->rdev->reg_data = data;
3046 }
3047 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3048
3049 /**
3050  * regulator_get_id - get regulator ID
3051  * @rdev: regulator
3052  */
3053 int rdev_get_id(struct regulator_dev *rdev)
3054 {
3055         return rdev->desc->id;
3056 }
3057 EXPORT_SYMBOL_GPL(rdev_get_id);
3058
3059 struct device *rdev_get_dev(struct regulator_dev *rdev)
3060 {
3061         return &rdev->dev;
3062 }
3063 EXPORT_SYMBOL_GPL(rdev_get_dev);
3064
3065 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
3066 {
3067         return reg_init_data->driver_data;
3068 }
3069 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
3070
3071 #ifdef CONFIG_DEBUG_FS
3072 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
3073                                     size_t count, loff_t *ppos)
3074 {
3075         char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
3076         ssize_t len, ret = 0;
3077         struct regulator_map *map;
3078
3079         if (!buf)
3080                 return -ENOMEM;
3081
3082         list_for_each_entry(map, &regulator_map_list, list) {
3083                 len = snprintf(buf + ret, PAGE_SIZE - ret,
3084                                "%s -> %s.%s\n",
3085                                rdev_get_name(map->regulator), map->dev_name,
3086                                map->supply);
3087                 if (len >= 0)
3088                         ret += len;
3089                 if (ret > PAGE_SIZE) {
3090                         ret = PAGE_SIZE;
3091                         break;
3092                 }
3093         }
3094
3095         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
3096
3097         kfree(buf);
3098
3099         return ret;
3100 }
3101 #endif
3102
3103 static const struct file_operations supply_map_fops = {
3104 #ifdef CONFIG_DEBUG_FS
3105         .read = supply_map_read_file,
3106         .llseek = default_llseek,
3107 #endif
3108 };
3109
3110 static int __init regulator_init(void)
3111 {
3112         int ret;
3113
3114         ret = class_register(&regulator_class);
3115
3116         debugfs_root = debugfs_create_dir("regulator", NULL);
3117         if (!debugfs_root)
3118                 pr_warn("regulator: Failed to create debugfs directory\n");
3119
3120         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
3121                             &supply_map_fops);
3122
3123         regulator_dummy_init();
3124
3125         return ret;
3126 }
3127
3128 /* init early to allow our consumers to complete system booting */
3129 core_initcall(regulator_init);
3130
3131 static int __init regulator_init_complete(void)
3132 {
3133         struct regulator_dev *rdev;
3134         struct regulator_ops *ops;
3135         struct regulation_constraints *c;
3136         int enabled, ret;
3137
3138         mutex_lock(&regulator_list_mutex);
3139
3140         /* If we have a full configuration then disable any regulators
3141          * which are not in use or always_on.  This will become the
3142          * default behaviour in the future.
3143          */
3144         list_for_each_entry(rdev, &regulator_list, list) {
3145                 ops = rdev->desc->ops;
3146                 c = rdev->constraints;
3147
3148                 if (!ops->disable || (c && c->always_on))
3149                         continue;
3150
3151                 mutex_lock(&rdev->mutex);
3152
3153                 if (rdev->use_count)
3154                         goto unlock;
3155
3156                 /* If we can't read the status assume it's on. */
3157                 if (ops->is_enabled)
3158                         enabled = ops->is_enabled(rdev);
3159                 else
3160                         enabled = 1;
3161
3162                 if (!enabled)
3163                         goto unlock;
3164
3165                 if (has_full_constraints) {
3166                         /* We log since this may kill the system if it
3167                          * goes wrong. */
3168                         rdev_info(rdev, "disabling\n");
3169                         ret = ops->disable(rdev);
3170                         if (ret != 0) {
3171                                 rdev_err(rdev, "couldn't disable: %d\n", ret);
3172                         }
3173                 } else {
3174                         /* The intention is that in future we will
3175                          * assume that full constraints are provided
3176                          * so warn even if we aren't going to do
3177                          * anything here.
3178                          */
3179                         rdev_warn(rdev, "incomplete constraints, leaving on\n");
3180                 }
3181
3182 unlock:
3183                 mutex_unlock(&rdev->mutex);
3184         }
3185
3186         mutex_unlock(&regulator_list_mutex);
3187
3188         return 0;
3189 }
3190 late_initcall(regulator_init_complete);