drivers/regulator/core.c

   1 /*
   2  * core.c  --  Voltage/Current Regulator framework.
   3  *
   4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
   5  * Copyright 2008 SlimLogic Ltd.
   6  *
   7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
   8  *
   9  *  This program is free software; you can redistribute  it and/or modify it
  10  *  under  the terms of  the GNU General  Public License as published by the
  11  *  Free Software Foundation;  either version 2 of the  License, or (at your
  12  *  option) any later version.
  13  *
  14  */
  15
  16 #define pr_fmt(fmt) "%s: " fmt, __func__
  17
  18 #include <linux/kernel.h>
  19 #include <linux/init.h>
  20 #include <linux/debugfs.h>
  21 #include <linux/device.h>
  22 #include <linux/slab.h>
  23 #include <linux/async.h>
  24 #include <linux/err.h>
  25 #include <linux/mutex.h>
  26 #include <linux/suspend.h>
  27 #include <linux/delay.h>
  28 #include <linux/of.h>
  29 #include <linux/regulator/of_regulator.h>
  30 #include <linux/regulator/consumer.h>
  31 #include <linux/regulator/driver.h>
  32 #include <linux/regulator/machine.h>
  33 #include <linux/module.h>
  34
  35 #define CREATE_TRACE_POINTS
  36 #include <trace/events/regulator.h>
  37
  38 #include "dummy.h"
  39
  40 #define rdev_crit(rdev, fmt, ...)                                       \
  41         pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  42 #define rdev_err(rdev, fmt, ...)                                        \
  43         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  44 #define rdev_warn(rdev, fmt, ...)                                       \
  45         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  46 #define rdev_info(rdev, fmt, ...)                                       \
  47         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  48 #define rdev_dbg(rdev, fmt, ...)                                        \
  49         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  50
  51 static DEFINE_MUTEX(regulator_list_mutex);
  52 static LIST_HEAD(regulator_list);
  53 static LIST_HEAD(regulator_map_list);
  54 static bool has_full_constraints;
  55 static bool board_wants_dummy_regulator;
  56
  57 #ifdef CONFIG_DEBUG_FS
  58 static struct dentry *debugfs_root;
  59 #endif
  60
  61 /*
  62  * struct regulator_map
  63  *
  64  * Used to provide symbolic supply names to devices.
  65  */
  66 struct regulator_map {
  67         struct list_head list;
  68         const char *dev_name;   /* The dev_name() for the consumer */
  69         const char *supply;
  70         struct regulator_dev *regulator;
  71 };
  72
  73 /*
  74  * struct regulator
  75  *
  76  * One for each consumer device.
  77  */
  78 struct regulator {
  79         struct device *dev;
  80         struct list_head list;
  81         int uA_load;
  82         int min_uV;
  83         int max_uV;
  84         char *supply_name;
  85         struct device_attribute dev_attr;
  86         struct regulator_dev *rdev;
  87 #ifdef CONFIG_DEBUG_FS
  88         struct dentry *debugfs;
  89 #endif
  90 };
  91
  92 static int _regulator_is_enabled(struct regulator_dev *rdev);
  93 static int _regulator_disable(struct regulator_dev *rdev);
  94 static int _regulator_get_voltage(struct regulator_dev *rdev);
  95 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  96 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  97 static void _notifier_call_chain(struct regulator_dev *rdev,
  98                                   unsigned long event, void *data);
  99 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
 100                                      int min_uV, int max_uV);
 101 static struct regulator *create_regulator(struct regulator_dev *rdev,
 102                                           struct device *dev,
 103                                           const char *supply_name);
 104
 105 static const char *rdev_get_name(struct regulator_dev *rdev)
 106 {
 107         if (rdev->constraints && rdev->constraints->name)
 108                 return rdev->constraints->name;
 109         else if (rdev->desc->name)
 110                 return rdev->desc->name;
 111         else
 112                 return "";
 113 }
 114
 115 /* gets the regulator for a given consumer device */
 116 static struct regulator *get_device_regulator(struct device *dev)
 117 {
 118         struct regulator *regulator = NULL;
 119         struct regulator_dev *rdev;
 120
 121         mutex_lock(&regulator_list_mutex);
 122         list_for_each_entry(rdev, &regulator_list, list) {
 123                 mutex_lock(&rdev->mutex);
 124                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
 125                         if (regulator->dev == dev) {
 126                                 mutex_unlock(&rdev->mutex);
 127                                 mutex_unlock(&regulator_list_mutex);
 128                                 return regulator;
 129                         }
 130                 }
 131                 mutex_unlock(&rdev->mutex);
 132         }
 133         mutex_unlock(&regulator_list_mutex);
 134         return NULL;
 135 }
 136
 137 /**
 138  * of_get_regulator - get a regulator device node based on supply name
 139  * @dev: Device pointer for the consumer (of regulator) device
 140  * @supply: regulator supply name
 141  *
 142  * Extract the regulator device node corresponding to the supply name.
 143  * retruns the device node corresponding to the regulator if found, else
 144  * returns NULL.
 145  */
 146 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 147 {
 148         struct device_node *regnode = NULL;
 149         char prop_name[32]; /* 32 is max size of property name */
 150
 151         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 152
 153         snprintf(prop_name, 32, "%s-supply", supply);
 154         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 155
 156         if (!regnode) {
 157                 dev_warn(dev, "%s property in node %s references invalid phandle",
 158                                 prop_name, dev->of_node->full_name);
 159                 return NULL;
 160         }
 161         return regnode;
 162 }
 163
 164 /* Platform voltage constraint check */
 165 static int regulator_check_voltage(struct regulator_dev *rdev,
 166                                    int *min_uV, int *max_uV)
 167 {
 168         BUG_ON(*min_uV > *max_uV);
 169
 170         if (!rdev->constraints) {
 171                 rdev_err(rdev, "no constraints\n");
 172                 return -ENODEV;
 173         }
 174         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 175                 rdev_err(rdev, "operation not allowed\n");
 176                 return -EPERM;
 177         }
 178
 179         if (*max_uV > rdev->constraints->max_uV)
 180                 *max_uV = rdev->constraints->max_uV;
 181         if (*min_uV < rdev->constraints->min_uV)
 182                 *min_uV = rdev->constraints->min_uV;
 183
 184         if (*min_uV > *max_uV) {
 185                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 186                          *min_uV, *max_uV);
 187                 return -EINVAL;
 188         }
 189
 190         return 0;
 191 }
 192
 193 /* Make sure we select a voltage that suits the needs of all
 194  * regulator consumers
 195  */
 196 static int regulator_check_consumers(struct regulator_dev *rdev,
 197                                      int *min_uV, int *max_uV)
 198 {
 199         struct regulator *regulator;
 200
 201         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 202                 /*
 203                  * Assume consumers that didn't say anything are OK
 204                  * with anything in the constraint range.
 205                  */
 206                 if (!regulator->min_uV && !regulator->max_uV)
 207                         continue;
 208
 209                 if (*max_uV > regulator->max_uV)
 210                         *max_uV = regulator->max_uV;
 211                 if (*min_uV < regulator->min_uV)
 212                         *min_uV = regulator->min_uV;
 213         }
 214
 215         if (*min_uV > *max_uV)
 216                 return -EINVAL;
 217
 218         return 0;
 219 }
 220
 221 /* current constraint check */
 222 static int regulator_check_current_limit(struct regulator_dev *rdev,
 223                                         int *min_uA, int *max_uA)
 224 {
 225         BUG_ON(*min_uA > *max_uA);
 226
 227         if (!rdev->constraints) {
 228                 rdev_err(rdev, "no constraints\n");
 229                 return -ENODEV;
 230         }
 231         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 232                 rdev_err(rdev, "operation not allowed\n");
 233                 return -EPERM;
 234         }
 235
 236         if (*max_uA > rdev->constraints->max_uA)
 237                 *max_uA = rdev->constraints->max_uA;
 238         if (*min_uA < rdev->constraints->min_uA)
 239                 *min_uA = rdev->constraints->min_uA;
 240
 241         if (*min_uA > *max_uA) {
 242                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 243                          *min_uA, *max_uA);
 244                 return -EINVAL;
 245         }
 246
 247         return 0;
 248 }
 249
 250 /* operating mode constraint check */
 251 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
 252 {
 253         switch (*mode) {
 254         case REGULATOR_MODE_FAST:
 255         case REGULATOR_MODE_NORMAL:
 256         case REGULATOR_MODE_IDLE:
 257         case REGULATOR_MODE_STANDBY:
 258                 break;
 259         default:
 260                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 261                 return -EINVAL;
 262         }
 263
 264         if (!rdev->constraints) {
 265                 rdev_err(rdev, "no constraints\n");
 266                 return -ENODEV;
 267         }
 268         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 269                 rdev_err(rdev, "operation not allowed\n");
 270                 return -EPERM;
 271         }
 272
 273         /* The modes are bitmasks, the most power hungry modes having
 274          * the lowest values. If the requested mode isn't supported
 275          * try higher modes. */
 276         while (*mode) {
 277                 if (rdev->constraints->valid_modes_mask & *mode)
 278                         return 0;
 279                 *mode /= 2;
 280         }
 281
 282         return -EINVAL;
 283 }
 284
 285 /* dynamic regulator mode switching constraint check */
 286 static int regulator_check_drms(struct regulator_dev *rdev)
 287 {
 288         if (!rdev->constraints) {
 289                 rdev_err(rdev, "no constraints\n");
 290                 return -ENODEV;
 291         }
 292         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 293                 rdev_err(rdev, "operation not allowed\n");
 294                 return -EPERM;
 295         }
 296         return 0;
 297 }
 298
 299 static ssize_t device_requested_uA_show(struct device *dev,
 300                              struct device_attribute *attr, char *buf)
 301 {
 302         struct regulator *regulator;
 303
 304         regulator = get_device_regulator(dev);
 305         if (regulator == NULL)
 306                 return 0;
 307
 308         return sprintf(buf, "%d\n", regulator->uA_load);
 309 }
 310
 311 static ssize_t regulator_uV_show(struct device *dev,
 312                                 struct device_attribute *attr, char *buf)
 313 {
 314         struct regulator_dev *rdev = dev_get_drvdata(dev);
 315         ssize_t ret;
 316
 317         mutex_lock(&rdev->mutex);
 318         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 319         mutex_unlock(&rdev->mutex);
 320
 321         return ret;
 322 }
 323 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 324
 325 static ssize_t regulator_uA_show(struct device *dev,
 326                                 struct device_attribute *attr, char *buf)
 327 {
 328         struct regulator_dev *rdev = dev_get_drvdata(dev);
 329
 330         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 331 }
 332 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 333
 334 static ssize_t regulator_name_show(struct device *dev,
 335                              struct device_attribute *attr, char *buf)
 336 {
 337         struct regulator_dev *rdev = dev_get_drvdata(dev);
 338
 339         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 340 }
 341
 342 static ssize_t regulator_print_opmode(char *buf, int mode)
 343 {
 344         switch (mode) {
 345         case REGULATOR_MODE_FAST:
 346                 return sprintf(buf, "fast\n");
 347         case REGULATOR_MODE_NORMAL:
 348                 return sprintf(buf, "normal\n");
 349         case REGULATOR_MODE_IDLE:
 350                 return sprintf(buf, "idle\n");
 351         case REGULATOR_MODE_STANDBY:
 352                 return sprintf(buf, "standby\n");
 353         }
 354         return sprintf(buf, "unknown\n");
 355 }
 356
 357 static ssize_t regulator_opmode_show(struct device *dev,
 358                                     struct device_attribute *attr, char *buf)
 359 {
 360         struct regulator_dev *rdev = dev_get_drvdata(dev);
 361
 362         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 363 }
 364 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 365
 366 static ssize_t regulator_print_state(char *buf, int state)
 367 {
 368         if (state > 0)
 369                 return sprintf(buf, "enabled\n");
 370         else if (state == 0)
 371                 return sprintf(buf, "disabled\n");
 372         else
 373                 return sprintf(buf, "unknown\n");
 374 }
 375
 376 static ssize_t regulator_state_show(struct device *dev,
 377                                    struct device_attribute *attr, char *buf)
 378 {
 379         struct regulator_dev *rdev = dev_get_drvdata(dev);
 380         ssize_t ret;
 381
 382         mutex_lock(&rdev->mutex);
 383         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 384         mutex_unlock(&rdev->mutex);
 385
 386         return ret;
 387 }
 388 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 389
 390 static ssize_t regulator_status_show(struct device *dev,
 391                                    struct device_attribute *attr, char *buf)
 392 {
 393         struct regulator_dev *rdev = dev_get_drvdata(dev);
 394         int status;
 395         char *label;
 396
 397         status = rdev->desc->ops->get_status(rdev);
 398         if (status < 0)
 399                 return status;
 400
 401         switch (status) {
 402         case REGULATOR_STATUS_OFF:
 403                 label = "off";
 404                 break;
 405         case REGULATOR_STATUS_ON:
 406                 label = "on";
 407                 break;
 408         case REGULATOR_STATUS_ERROR:
 409                 label = "error";
 410                 break;
 411         case REGULATOR_STATUS_FAST:
 412                 label = "fast";
 413                 break;
 414         case REGULATOR_STATUS_NORMAL:
 415                 label = "normal";
 416                 break;
 417         case REGULATOR_STATUS_IDLE:
 418                 label = "idle";
 419                 break;
 420         case REGULATOR_STATUS_STANDBY:
 421                 label = "standby";
 422                 break;
 423         default:
 424                 return -ERANGE;
 425         }
 426
 427         return sprintf(buf, "%s\n", label);
 428 }
 429 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 430
 431 static ssize_t regulator_min_uA_show(struct device *dev,
 432                                     struct device_attribute *attr, char *buf)
 433 {
 434         struct regulator_dev *rdev = dev_get_drvdata(dev);
 435
 436         if (!rdev->constraints)
 437                 return sprintf(buf, "constraint not defined\n");
 438
 439         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 440 }
 441 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 442
 443 static ssize_t regulator_max_uA_show(struct device *dev,
 444                                     struct device_attribute *attr, char *buf)
 445 {
 446         struct regulator_dev *rdev = dev_get_drvdata(dev);
 447
 448         if (!rdev->constraints)
 449                 return sprintf(buf, "constraint not defined\n");
 450
 451         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 452 }
 453 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 454
 455 static ssize_t regulator_min_uV_show(struct device *dev,
 456                                     struct device_attribute *attr, char *buf)
 457 {
 458         struct regulator_dev *rdev = dev_get_drvdata(dev);
 459
 460         if (!rdev->constraints)
 461                 return sprintf(buf, "constraint not defined\n");
 462
 463         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 464 }
 465 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 466
 467 static ssize_t regulator_max_uV_show(struct device *dev,
 468                                     struct device_attribute *attr, char *buf)
 469 {
 470         struct regulator_dev *rdev = dev_get_drvdata(dev);
 471
 472         if (!rdev->constraints)
 473                 return sprintf(buf, "constraint not defined\n");
 474
 475         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 476 }
 477 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 478
 479 static ssize_t regulator_total_uA_show(struct device *dev,
 480                                       struct device_attribute *attr, char *buf)
 481 {
 482         struct regulator_dev *rdev = dev_get_drvdata(dev);
 483         struct regulator *regulator;
 484         int uA = 0;
 485
 486         mutex_lock(&rdev->mutex);
 487         list_for_each_entry(regulator, &rdev->consumer_list, list)
 488                 uA += regulator->uA_load;
 489         mutex_unlock(&rdev->mutex);
 490         return sprintf(buf, "%d\n", uA);
 491 }
 492 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 493
 494 static ssize_t regulator_num_users_show(struct device *dev,
 495                                       struct device_attribute *attr, char *buf)
 496 {
 497         struct regulator_dev *rdev = dev_get_drvdata(dev);
 498         return sprintf(buf, "%d\n", rdev->use_count);
 499 }
 500
 501 static ssize_t regulator_type_show(struct device *dev,
 502                                   struct device_attribute *attr, char *buf)
 503 {
 504         struct regulator_dev *rdev = dev_get_drvdata(dev);
 505
 506         switch (rdev->desc->type) {
 507         case REGULATOR_VOLTAGE:
 508                 return sprintf(buf, "voltage\n");
 509         case REGULATOR_CURRENT:
 510                 return sprintf(buf, "current\n");
 511         }
 512         return sprintf(buf, "unknown\n");
 513 }
 514
 515 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 516                                 struct device_attribute *attr, char *buf)
 517 {
 518         struct regulator_dev *rdev = dev_get_drvdata(dev);
 519
 520         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 521 }
 522 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 523                 regulator_suspend_mem_uV_show, NULL);
 524
 525 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 526                                 struct device_attribute *attr, char *buf)
 527 {
 528         struct regulator_dev *rdev = dev_get_drvdata(dev);
 529
 530         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 531 }
 532 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 533                 regulator_suspend_disk_uV_show, NULL);
 534
 535 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 536                                 struct device_attribute *attr, char *buf)
 537 {
 538         struct regulator_dev *rdev = dev_get_drvdata(dev);
 539
 540         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 541 }
 542 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 543                 regulator_suspend_standby_uV_show, NULL);
 544
 545 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 546                                 struct device_attribute *attr, char *buf)
 547 {
 548         struct regulator_dev *rdev = dev_get_drvdata(dev);
 549
 550         return regulator_print_opmode(buf,
 551                 rdev->constraints->state_mem.mode);
 552 }
 553 static DEVICE_ATTR(suspend_mem_mode, 0444,
 554                 regulator_suspend_mem_mode_show, NULL);
 555
 556 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 557                                 struct device_attribute *attr, char *buf)
 558 {
 559         struct regulator_dev *rdev = dev_get_drvdata(dev);
 560
 561         return regulator_print_opmode(buf,
 562                 rdev->constraints->state_disk.mode);
 563 }
 564 static DEVICE_ATTR(suspend_disk_mode, 0444,
 565                 regulator_suspend_disk_mode_show, NULL);
 566
 567 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 568                                 struct device_attribute *attr, char *buf)
 569 {
 570         struct regulator_dev *rdev = dev_get_drvdata(dev);
 571
 572         return regulator_print_opmode(buf,
 573                 rdev->constraints->state_standby.mode);
 574 }
 575 static DEVICE_ATTR(suspend_standby_mode, 0444,
 576                 regulator_suspend_standby_mode_show, NULL);
 577
 578 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 579                                    struct device_attribute *attr, char *buf)
 580 {
 581         struct regulator_dev *rdev = dev_get_drvdata(dev);
 582
 583         return regulator_print_state(buf,
 584                         rdev->constraints->state_mem.enabled);
 585 }
 586 static DEVICE_ATTR(suspend_mem_state, 0444,
 587                 regulator_suspend_mem_state_show, NULL);
 588
 589 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 590                                    struct device_attribute *attr, char *buf)
 591 {
 592         struct regulator_dev *rdev = dev_get_drvdata(dev);
 593
 594         return regulator_print_state(buf,
 595                         rdev->constraints->state_disk.enabled);
 596 }
 597 static DEVICE_ATTR(suspend_disk_state, 0444,
 598                 regulator_suspend_disk_state_show, NULL);
 599
 600 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 601                                    struct device_attribute *attr, char *buf)
 602 {
 603         struct regulator_dev *rdev = dev_get_drvdata(dev);
 604
 605         return regulator_print_state(buf,
 606                         rdev->constraints->state_standby.enabled);
 607 }
 608 static DEVICE_ATTR(suspend_standby_state, 0444,
 609                 regulator_suspend_standby_state_show, NULL);
 610
 611
 612 /*
 613  * These are the only attributes are present for all regulators.
 614  * Other attributes are a function of regulator functionality.
 615  */
 616 static struct device_attribute regulator_dev_attrs[] = {
 617         __ATTR(name, 0444, regulator_name_show, NULL),
 618         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
 619         __ATTR(type, 0444, regulator_type_show, NULL),
 620         __ATTR_NULL,
 621 };
 622
 623 static void regulator_dev_release(struct device *dev)
 624 {
 625         struct regulator_dev *rdev = dev_get_drvdata(dev);
 626         kfree(rdev);
 627 }
 628
 629 static struct class regulator_class = {
 630         .name = "regulator",
 631         .dev_release = regulator_dev_release,
 632         .dev_attrs = regulator_dev_attrs,
 633 };
 634
 635 /* Calculate the new optimum regulator operating mode based on the new total
 636  * consumer load. All locks held by caller */
 637 static void drms_uA_update(struct regulator_dev *rdev)
 638 {
 639         struct regulator *sibling;
 640         int current_uA = 0, output_uV, input_uV, err;
 641         unsigned int mode;
 642
 643         err = regulator_check_drms(rdev);
 644         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 645             (!rdev->desc->ops->get_voltage &&
 646              !rdev->desc->ops->get_voltage_sel) ||
 647             !rdev->desc->ops->set_mode)
 648                 return;
 649
 650         /* get output voltage */
 651         output_uV = _regulator_get_voltage(rdev);
 652         if (output_uV <= 0)
 653                 return;
 654
 655         /* get input voltage */
 656         input_uV = 0;
 657         if (rdev->supply)
 658                 input_uV = _regulator_get_voltage(rdev);
 659         if (input_uV <= 0)
 660                 input_uV = rdev->constraints->input_uV;
 661         if (input_uV <= 0)
 662                 return;
 663
 664         /* calc total requested load */
 665         list_for_each_entry(sibling, &rdev->consumer_list, list)
 666                 current_uA += sibling->uA_load;
 667
 668         /* now get the optimum mode for our new total regulator load */
 669         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 670                                                   output_uV, current_uA);
 671
 672         /* check the new mode is allowed */
 673         err = regulator_mode_constrain(rdev, &mode);
 674         if (err == 0)
 675                 rdev->desc->ops->set_mode(rdev, mode);
 676 }
 677
 678 static int suspend_set_state(struct regulator_dev *rdev,
 679         struct regulator_state *rstate)
 680 {
 681         int ret = 0;
 682         bool can_set_state;
 683
 684         can_set_state = rdev->desc->ops->set_suspend_enable &&
 685                 rdev->desc->ops->set_suspend_disable;
 686
 687         /* If we have no suspend mode configration don't set anything;
 688          * only warn if the driver actually makes the suspend mode
 689          * configurable.
 690          */
 691         if (!rstate->enabled && !rstate->disabled) {
 692                 if (can_set_state)
 693                         rdev_warn(rdev, "No configuration\n");
 694                 return 0;
 695         }
 696
 697         if (rstate->enabled && rstate->disabled) {
 698                 rdev_err(rdev, "invalid configuration\n");
 699                 return -EINVAL;
 700         }
 701
 702         if (!can_set_state) {
 703                 rdev_err(rdev, "no way to set suspend state\n");
 704                 return -EINVAL;
 705         }
 706
 707         if (rstate->enabled)
 708                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 709         else
 710                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 711         if (ret < 0) {
 712                 rdev_err(rdev, "failed to enabled/disable\n");
 713                 return ret;
 714         }
 715
 716         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 717                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 718                 if (ret < 0) {
 719                         rdev_err(rdev, "failed to set voltage\n");
 720                         return ret;
 721                 }
 722         }
 723
 724         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 725                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 726                 if (ret < 0) {
 727                         rdev_err(rdev, "failed to set mode\n");
 728                         return ret;
 729                 }
 730         }
 731         return ret;
 732 }
 733
 734 /* locks held by caller */
 735 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 736 {
 737         if (!rdev->constraints)
 738                 return -EINVAL;
 739
 740         switch (state) {
 741         case PM_SUSPEND_STANDBY:
 742                 return suspend_set_state(rdev,
 743                         &rdev->constraints->state_standby);
 744         case PM_SUSPEND_MEM:
 745                 return suspend_set_state(rdev,
 746                         &rdev->constraints->state_mem);
 747         case PM_SUSPEND_MAX:
 748                 return suspend_set_state(rdev,
 749                         &rdev->constraints->state_disk);
 750         default:
 751                 return -EINVAL;
 752         }
 753 }
 754
 755 static void print_constraints(struct regulator_dev *rdev)
 756 {
 757         struct regulation_constraints *constraints = rdev->constraints;
 758         char buf[80] = "";
 759         int count = 0;
 760         int ret;
 761
 762         if (constraints->min_uV && constraints->max_uV) {
 763                 if (constraints->min_uV == constraints->max_uV)
 764                         count += sprintf(buf + count, "%d mV ",
 765                                          constraints->min_uV / 1000);
 766                 else
 767                         count += sprintf(buf + count, "%d <--> %d mV ",
 768                                          constraints->min_uV / 1000,
 769                                          constraints->max_uV / 1000);
 770         }
 771
 772         if (!constraints->min_uV ||
 773             constraints->min_uV != constraints->max_uV) {
 774                 ret = _regulator_get_voltage(rdev);
 775                 if (ret > 0)
 776                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 777         }
 778
 779         if (constraints->uV_offset)
 780                 count += sprintf(buf, "%dmV offset ",
 781                                  constraints->uV_offset / 1000);
 782
 783         if (constraints->min_uA && constraints->max_uA) {
 784                 if (constraints->min_uA == constraints->max_uA)
 785                         count += sprintf(buf + count, "%d mA ",
 786                                          constraints->min_uA / 1000);
 787                 else
 788                         count += sprintf(buf + count, "%d <--> %d mA ",
 789                                          constraints->min_uA / 1000,
 790                                          constraints->max_uA / 1000);
 791         }
 792
 793         if (!constraints->min_uA ||
 794             constraints->min_uA != constraints->max_uA) {
 795                 ret = _regulator_get_current_limit(rdev);
 796                 if (ret > 0)
 797                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
 798         }
 799
 800         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 801                 count += sprintf(buf + count, "fast ");
 802         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 803                 count += sprintf(buf + count, "normal ");
 804         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 805                 count += sprintf(buf + count, "idle ");
 806         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 807                 count += sprintf(buf + count, "standby");
 808
 809         rdev_info(rdev, "%s\n", buf);
 810 }
 811
 812 static int machine_constraints_voltage(struct regulator_dev *rdev,
 813         struct regulation_constraints *constraints)
 814 {
 815         struct regulator_ops *ops = rdev->desc->ops;
 816         int ret;
 817
 818         /* do we need to apply the constraint voltage */
 819         if (rdev->constraints->apply_uV &&
 820             rdev->constraints->min_uV == rdev->constraints->max_uV) {
 821                 ret = _regulator_do_set_voltage(rdev,
 822                                                 rdev->constraints->min_uV,
 823                                                 rdev->constraints->max_uV);
 824                 if (ret < 0) {
 825                         rdev_err(rdev, "failed to apply %duV constraint\n",
 826                                  rdev->constraints->min_uV);
 827                         return ret;
 828                 }
 829         }
 830
 831         /* constrain machine-level voltage specs to fit
 832          * the actual range supported by this regulator.
 833          */
 834         if (ops->list_voltage && rdev->desc->n_voltages) {
 835                 int     count = rdev->desc->n_voltages;
 836                 int     i;
 837                 int     min_uV = INT_MAX;
 838                 int     max_uV = INT_MIN;
 839                 int     cmin = constraints->min_uV;
 840                 int     cmax = constraints->max_uV;
 841
 842                 /* it's safe to autoconfigure fixed-voltage supplies
 843                    and the constraints are used by list_voltage. */
 844                 if (count == 1 && !cmin) {
 845                         cmin = 1;
 846                         cmax = INT_MAX;
 847                         constraints->min_uV = cmin;
 848                         constraints->max_uV = cmax;
 849                 }
 850
 851                 /* voltage constraints are optional */
 852                 if ((cmin == 0) && (cmax == 0))
 853                         return 0;
 854
 855                 /* else require explicit machine-level constraints */
 856                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 857                         rdev_err(rdev, "invalid voltage constraints\n");
 858                         return -EINVAL;
 859                 }
 860
 861                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 862                 for (i = 0; i < count; i++) {
 863                         int     value;
 864
 865                         value = ops->list_voltage(rdev, i);
 866                         if (value <= 0)
 867                                 continue;
 868
 869                         /* maybe adjust [min_uV..max_uV] */
 870                         if (value >= cmin && value < min_uV)
 871                                 min_uV = value;
 872                         if (value <= cmax && value > max_uV)
 873                                 max_uV = value;
 874                 }
 875
 876                 /* final: [min_uV..max_uV] valid iff constraints valid */
 877                 if (max_uV < min_uV) {
 878                         rdev_err(rdev, "unsupportable voltage constraints\n");
 879                         return -EINVAL;
 880                 }
 881
 882                 /* use regulator's subset of machine constraints */
 883                 if (constraints->min_uV < min_uV) {
 884                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
 885                                  constraints->min_uV, min_uV);
 886                         constraints->min_uV = min_uV;
 887                 }
 888                 if (constraints->max_uV > max_uV) {
 889                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
 890                                  constraints->max_uV, max_uV);
 891                         constraints->max_uV = max_uV;
 892                 }
 893         }
 894
 895         return 0;
 896 }
 897
 898 /**
 899  * set_machine_constraints - sets regulator constraints
 900  * @rdev: regulator source
 901  * @constraints: constraints to apply
 902  *
 903  * Allows platform initialisation code to define and constrain
 904  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 905  * Constraints *must* be set by platform code in order for some
 906  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 907  * set_mode.
 908  */
 909 static int set_machine_constraints(struct regulator_dev *rdev,
 910         const struct regulation_constraints *constraints)
 911 {
 912         int ret = 0;
 913         struct regulator_ops *ops = rdev->desc->ops;
 914
 915         if (constraints)
 916                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
 917                                             GFP_KERNEL);
 918         else
 919                 rdev->constraints = kzalloc(sizeof(*constraints),
 920                                             GFP_KERNEL);
 921         if (!rdev->constraints)
 922                 return -ENOMEM;
 923
 924         ret = machine_constraints_voltage(rdev, rdev->constraints);
 925         if (ret != 0)
 926                 goto out;
 927
 928         /* do we need to setup our suspend state */
 929         if (rdev->constraints->initial_state) {
 930                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
 931                 if (ret < 0) {
 932                         rdev_err(rdev, "failed to set suspend state\n");
 933                         goto out;
 934                 }
 935         }
 936
 937         if (rdev->constraints->initial_mode) {
 938                 if (!ops->set_mode) {
 939                         rdev_err(rdev, "no set_mode operation\n");
 940                         ret = -EINVAL;
 941                         goto out;
 942                 }
 943
 944                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
 945                 if (ret < 0) {
 946                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
 947                         goto out;
 948                 }
 949         }
 950
 951         /* If the constraints say the regulator should be on at this point
 952          * and we have control then make sure it is enabled.
 953          */
 954         if ((rdev->constraints->always_on || rdev->constraints->boot_on) &&
 955             ops->enable) {
 956                 ret = ops->enable(rdev);
 957                 if (ret < 0) {
 958                         rdev_err(rdev, "failed to enable\n");
 959                         goto out;
 960                 }
 961         }
 962
 963         print_constraints(rdev);
 964         return 0;
 965 out:
 966         kfree(rdev->constraints);
 967         rdev->constraints = NULL;
 968         return ret;
 969 }
 970
 971 /**
 972  * set_supply - set regulator supply regulator
 973  * @rdev: regulator name
 974  * @supply_rdev: supply regulator name
 975  *
 976  * Called by platform initialisation code to set the supply regulator for this
 977  * regulator. This ensures that a regulators supply will also be enabled by the
 978  * core if it's child is enabled.
 979  */
 980 static int set_supply(struct regulator_dev *rdev,
 981                       struct regulator_dev *supply_rdev)
 982 {
 983         int err;
 984
 985         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
 986
 987         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
 988         if (rdev->supply == NULL) {
 989                 err = -ENOMEM;
 990                 return err;
 991         }
 992
 993         return 0;
 994 }
 995
 996 /**
 997  * set_consumer_device_supply - Bind a regulator to a symbolic supply
 998  * @rdev:         regulator source
 999  * @consumer_dev: device the supply applies to
1000  * @consumer_dev_name: dev_name() string for device supply applies to
1001  * @supply:       symbolic name for supply
1002  *
1003  * Allows platform initialisation code to map physical regulator
1004  * sources to symbolic names for supplies for use by devices.  Devices
1005  * should use these symbolic names to request regulators, avoiding the
1006  * need to provide board-specific regulator names as platform data.
1007  *
1008  * Only one of consumer_dev and consumer_dev_name may be specified.
1009  */
1010 static int set_consumer_device_supply(struct regulator_dev *rdev,
1011         struct device *consumer_dev, const char *consumer_dev_name,
1012         const char *supply)
1013 {
1014         struct regulator_map *node;
1015         int has_dev;
1016
1017         if (consumer_dev && consumer_dev_name)
1018                 return -EINVAL;
1019
1020         if (!consumer_dev_name && consumer_dev)
1021                 consumer_dev_name = dev_name(consumer_dev);
1022
1023         if (supply == NULL)
1024                 return -EINVAL;
1025
1026         if (consumer_dev_name != NULL)
1027                 has_dev = 1;
1028         else
1029                 has_dev = 0;
1030
1031         list_for_each_entry(node, &regulator_map_list, list) {
1032                 if (node->dev_name && consumer_dev_name) {
1033                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1034                                 continue;
1035                 } else if (node->dev_name || consumer_dev_name) {
1036                         continue;
1037                 }
1038
1039                 if (strcmp(node->supply, supply) != 0)
1040                         continue;
1041
1042                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
1043                         dev_name(&node->regulator->dev),
1044                         node->regulator->desc->name,
1045                         supply,
1046                         dev_name(&rdev->dev), rdev_get_name(rdev));
1047                 return -EBUSY;
1048         }
1049
1050         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1051         if (node == NULL)
1052                 return -ENOMEM;
1053
1054         node->regulator = rdev;
1055         node->supply = supply;
1056
1057         if (has_dev) {
1058                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1059                 if (node->dev_name == NULL) {
1060                         kfree(node);
1061                         return -ENOMEM;
1062                 }
1063         }
1064
1065         list_add(&node->list, &regulator_map_list);
1066         return 0;
1067 }
1068
1069 static void unset_regulator_supplies(struct regulator_dev *rdev)
1070 {
1071         struct regulator_map *node, *n;
1072
1073         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1074                 if (rdev == node->regulator) {
1075                         list_del(&node->list);
1076                         kfree(node->dev_name);
1077                         kfree(node);
1078                 }
1079         }
1080 }
1081
1082 #define REG_STR_SIZE    64
1083
1084 static struct regulator *create_regulator(struct regulator_dev *rdev,
1085                                           struct device *dev,
1086                                           const char *supply_name)
1087 {
1088         struct regulator *regulator;
1089         char buf[REG_STR_SIZE];
1090         int err, size;
1091
1092         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1093         if (regulator == NULL)
1094                 return NULL;
1095
1096         mutex_lock(&rdev->mutex);
1097         regulator->rdev = rdev;
1098         list_add(&regulator->list, &rdev->consumer_list);
1099
1100         if (dev) {
1101                 /* create a 'requested_microamps_name' sysfs entry */
1102                 size = scnprintf(buf, REG_STR_SIZE,
1103                                  "microamps_requested_%s-%s",
1104                                  dev_name(dev), supply_name);
1105                 if (size >= REG_STR_SIZE)
1106                         goto overflow_err;
1107
1108                 regulator->dev = dev;
1109                 sysfs_attr_init(&regulator->dev_attr.attr);
1110                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1111                 if (regulator->dev_attr.attr.name == NULL)
1112                         goto attr_name_err;
1113
1114                 regulator->dev_attr.attr.mode = 0444;
1115                 regulator->dev_attr.show = device_requested_uA_show;
1116                 err = device_create_file(dev, &regulator->dev_attr);
1117                 if (err < 0) {
1118                         rdev_warn(rdev, "could not add regulator_dev requested microamps sysfs entry\n");
1119                         goto attr_name_err;
1120                 }
1121
1122                 /* also add a link to the device sysfs entry */
1123                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1124                                  dev->kobj.name, supply_name);
1125                 if (size >= REG_STR_SIZE)
1126                         goto attr_err;
1127
1128                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1129                 if (regulator->supply_name == NULL)
1130                         goto attr_err;
1131
1132                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1133                                         buf);
1134                 if (err) {
1135                         rdev_warn(rdev, "could not add device link %s err %d\n",
1136                                   dev->kobj.name, err);
1137                         goto link_name_err;
1138                 }
1139         } else {
1140                 regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1141                 if (regulator->supply_name == NULL)
1142                         goto attr_err;
1143         }
1144
1145 #ifdef CONFIG_DEBUG_FS
1146         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1147                                                 rdev->debugfs);
1148         if (IS_ERR_OR_NULL(regulator->debugfs)) {
1149                 rdev_warn(rdev, "Failed to create debugfs directory\n");
1150                 regulator->debugfs = NULL;
1151         } else {
1152                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1153                                    &regulator->uA_load);
1154                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1155                                    &regulator->min_uV);
1156                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1157                                    &regulator->max_uV);
1158         }
1159 #endif
1160
1161         mutex_unlock(&rdev->mutex);
1162         return regulator;
1163 link_name_err:
1164         kfree(regulator->supply_name);
1165 attr_err:
1166         device_remove_file(regulator->dev, &regulator->dev_attr);
1167 attr_name_err:
1168         kfree(regulator->dev_attr.attr.name);
1169 overflow_err:
1170         list_del(&regulator->list);
1171         kfree(regulator);
1172         mutex_unlock(&rdev->mutex);
1173         return NULL;
1174 }
1175
1176 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1177 {
1178         if (!rdev->desc->ops->enable_time)
1179                 return 0;
1180         return rdev->desc->ops->enable_time(rdev);
1181 }
1182
1183 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1184                                                          const char *supply)
1185 {
1186         struct regulator_dev *r;
1187         struct device_node *node;
1188
1189         /* first do a dt based lookup */
1190         if (dev && dev->of_node) {
1191                 node = of_get_regulator(dev, supply);
1192                 if (node)
1193                         list_for_each_entry(r, &regulator_list, list)
1194                                 if (r->dev.parent &&
1195                                         node == r->dev.of_node)
1196                                         return r;
1197         }
1198
1199         /* if not found, try doing it non-dt way */
1200         list_for_each_entry(r, &regulator_list, list)
1201                 if (strcmp(rdev_get_name(r), supply) == 0)
1202                         return r;
1203
1204         return NULL;
1205 }
1206
1207 /* Internal regulator request function */
1208 static struct regulator *_regulator_get(struct device *dev, const char *id,
1209                                         int exclusive)
1210 {
1211         struct regulator_dev *rdev;
1212         struct regulator_map *map;
1213         struct regulator *regulator = ERR_PTR(-ENODEV);
1214         const char *devname = NULL;
1215         int ret;
1216
1217         if (id == NULL) {
1218                 pr_err("get() with no identifier\n");
1219                 return regulator;
1220         }
1221
1222         if (dev)
1223                 devname = dev_name(dev);
1224
1225         mutex_lock(&regulator_list_mutex);
1226
1227         rdev = regulator_dev_lookup(dev, id);
1228         if (rdev)
1229                 goto found;
1230
1231         list_for_each_entry(map, &regulator_map_list, list) {
1232                 /* If the mapping has a device set up it must match */
1233                 if (map->dev_name &&
1234                     (!devname || strcmp(map->dev_name, devname)))
1235                         continue;
1236
1237                 if (strcmp(map->supply, id) == 0) {
1238                         rdev = map->regulator;
1239                         goto found;
1240                 }
1241         }
1242
1243         if (board_wants_dummy_regulator) {
1244                 rdev = dummy_regulator_rdev;
1245                 goto found;
1246         }
1247
1248 #ifdef CONFIG_REGULATOR_DUMMY
1249         if (!devname)
1250                 devname = "deviceless";
1251
1252         /* If the board didn't flag that it was fully constrained then
1253          * substitute in a dummy regulator so consumers can continue.
1254          */
1255         if (!has_full_constraints) {
1256                 pr_warn("%s supply %s not found, using dummy regulator\n",
1257                         devname, id);
1258                 rdev = dummy_regulator_rdev;
1259                 goto found;
1260         }
1261 #endif
1262
1263         mutex_unlock(&regulator_list_mutex);
1264         return regulator;
1265
1266 found:
1267         if (rdev->exclusive) {
1268                 regulator = ERR_PTR(-EPERM);
1269                 goto out;
1270         }
1271
1272         if (exclusive && rdev->open_count) {
1273                 regulator = ERR_PTR(-EBUSY);
1274                 goto out;
1275         }
1276
1277         if (!try_module_get(rdev->owner))
1278                 goto out;
1279
1280         regulator = create_regulator(rdev, dev, id);
1281         if (regulator == NULL) {
1282                 regulator = ERR_PTR(-ENOMEM);
1283                 module_put(rdev->owner);
1284                 goto out;
1285         }
1286
1287         rdev->open_count++;
1288         if (exclusive) {
1289                 rdev->exclusive = 1;
1290
1291                 ret = _regulator_is_enabled(rdev);
1292                 if (ret > 0)
1293                         rdev->use_count = 1;
1294                 else
1295                         rdev->use_count = 0;
1296         }
1297
1298 out:
1299         mutex_unlock(&regulator_list_mutex);
1300
1301         return regulator;
1302 }
1303
1304 /**
1305  * regulator_get - lookup and obtain a reference to a regulator.
1306  * @dev: device for regulator "consumer"
1307  * @id: Supply name or regulator ID.
1308  *
1309  * Returns a struct regulator corresponding to the regulator producer,
1310  * or IS_ERR() condition containing errno.
1311  *
1312  * Use of supply names configured via regulator_set_device_supply() is
1313  * strongly encouraged.  It is recommended that the supply name used
1314  * should match the name used for the supply and/or the relevant
1315  * device pins in the datasheet.
1316  */
1317 struct regulator *regulator_get(struct device *dev, const char *id)
1318 {
1319         return _regulator_get(dev, id, 0);
1320 }
1321 EXPORT_SYMBOL_GPL(regulator_get);
1322
1323 /**
1324  * regulator_get_exclusive - obtain exclusive access to a regulator.
1325  * @dev: device for regulator "consumer"
1326  * @id: Supply name or regulator ID.
1327  *
1328  * Returns a struct regulator corresponding to the regulator producer,
1329  * or IS_ERR() condition containing errno.  Other consumers will be
1330  * unable to obtain this reference is held and the use count for the
1331  * regulator will be initialised to reflect the current state of the
1332  * regulator.
1333  *
1334  * This is intended for use by consumers which cannot tolerate shared
1335  * use of the regulator such as those which need to force the
1336  * regulator off for correct operation of the hardware they are
1337  * controlling.
1338  *
1339  * Use of supply names configured via regulator_set_device_supply() is
1340  * strongly encouraged.  It is recommended that the supply name used
1341  * should match the name used for the supply and/or the relevant
1342  * device pins in the datasheet.
1343  */
1344 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1345 {
1346         return _regulator_get(dev, id, 1);
1347 }
1348 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1349
1350 /**
1351  * regulator_put - "free" the regulator source
1352  * @regulator: regulator source
1353  *
1354  * Note: drivers must ensure that all regulator_enable calls made on this
1355  * regulator source are balanced by regulator_disable calls prior to calling
1356  * this function.
1357  */
1358 void regulator_put(struct regulator *regulator)
1359 {
1360         struct regulator_dev *rdev;
1361
1362         if (regulator == NULL || IS_ERR(regulator))
1363                 return;
1364
1365         mutex_lock(&regulator_list_mutex);
1366         rdev = regulator->rdev;
1367
1368 #ifdef CONFIG_DEBUG_FS
1369         debugfs_remove_recursive(regulator->debugfs);
1370 #endif
1371
1372         /* remove any sysfs entries */
1373         if (regulator->dev) {
1374                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1375                 device_remove_file(regulator->dev, &regulator->dev_attr);
1376                 kfree(regulator->dev_attr.attr.name);
1377         }
1378         kfree(regulator->supply_name);
1379         list_del(&regulator->list);
1380         kfree(regulator);
1381
1382         rdev->open_count--;
1383         rdev->exclusive = 0;
1384
1385         module_put(rdev->owner);
1386         mutex_unlock(&regulator_list_mutex);
1387 }
1388 EXPORT_SYMBOL_GPL(regulator_put);
1389
1390 static int _regulator_can_change_status(struct regulator_dev *rdev)
1391 {
1392         if (!rdev->constraints)
1393                 return 0;
1394
1395         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1396                 return 1;
1397         else
1398                 return 0;
1399 }
1400
1401 /* locks held by regulator_enable() */
1402 static int _regulator_enable(struct regulator_dev *rdev)
1403 {
1404         int ret, delay;
1405
1406         /* check voltage and requested load before enabling */
1407         if (rdev->constraints &&
1408             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1409                 drms_uA_update(rdev);
1410
1411         if (rdev->use_count == 0) {
1412                 /* The regulator may on if it's not switchable or left on */
1413                 ret = _regulator_is_enabled(rdev);
1414                 if (ret == -EINVAL || ret == 0) {
1415                         if (!_regulator_can_change_status(rdev))
1416                                 return -EPERM;
1417
1418                         if (!rdev->desc->ops->enable)
1419                                 return -EINVAL;
1420
1421                         /* Query before enabling in case configuration
1422                          * dependent.  */
1423                         ret = _regulator_get_enable_time(rdev);
1424                         if (ret >= 0) {
1425                                 delay = ret;
1426                         } else {
1427                                 rdev_warn(rdev, "enable_time() failed: %d\n",
1428                                            ret);
1429                                 delay = 0;
1430                         }
1431
1432                         trace_regulator_enable(rdev_get_name(rdev));
1433
1434                         /* Allow the regulator to ramp; it would be useful
1435                          * to extend this for bulk operations so that the
1436                          * regulators can ramp together.  */
1437                         ret = rdev->desc->ops->enable(rdev);
1438                         if (ret < 0)
1439                                 return ret;
1440
1441                         trace_regulator_enable_delay(rdev_get_name(rdev));
1442
1443                         if (delay >= 1000) {
1444                                 mdelay(delay / 1000);
1445                                 udelay(delay % 1000);
1446                         } else if (delay) {
1447                                 udelay(delay);
1448                         }
1449
1450                         trace_regulator_enable_complete(rdev_get_name(rdev));
1451
1452                 } else if (ret < 0) {
1453                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1454                         return ret;
1455                 }
1456                 /* Fallthrough on positive return values - already enabled */
1457         }
1458
1459         rdev->use_count++;
1460
1461         return 0;
1462 }
1463
1464 /**
1465  * regulator_enable - enable regulator output
1466  * @regulator: regulator source
1467  *
1468  * Request that the regulator be enabled with the regulator output at
1469  * the predefined voltage or current value.  Calls to regulator_enable()
1470  * must be balanced with calls to regulator_disable().
1471  *
1472  * NOTE: the output value can be set by other drivers, boot loader or may be
1473  * hardwired in the regulator.
1474  */
1475 int regulator_enable(struct regulator *regulator)
1476 {
1477         struct regulator_dev *rdev = regulator->rdev;
1478         int ret = 0;
1479
1480         if (rdev->supply) {
1481                 ret = regulator_enable(rdev->supply);
1482                 if (ret != 0)
1483                         return ret;
1484         }
1485
1486         mutex_lock(&rdev->mutex);
1487         ret = _regulator_enable(rdev);
1488         mutex_unlock(&rdev->mutex);
1489
1490         if (ret != 0 && rdev->supply)
1491                 regulator_disable(rdev->supply);
1492
1493         return ret;
1494 }
1495 EXPORT_SYMBOL_GPL(regulator_enable);
1496
1497 /* locks held by regulator_disable() */
1498 static int _regulator_disable(struct regulator_dev *rdev)
1499 {
1500         int ret = 0;
1501
1502         if (WARN(rdev->use_count <= 0,
1503                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
1504                 return -EIO;
1505
1506         /* are we the last user and permitted to disable ? */
1507         if (rdev->use_count == 1 &&
1508             (rdev->constraints && !rdev->constraints->always_on)) {
1509
1510                 /* we are last user */
1511                 if (_regulator_can_change_status(rdev) &&
1512                     rdev->desc->ops->disable) {
1513                         trace_regulator_disable(rdev_get_name(rdev));
1514
1515                         ret = rdev->desc->ops->disable(rdev);
1516                         if (ret < 0) {
1517                                 rdev_err(rdev, "failed to disable\n");
1518                                 return ret;
1519                         }
1520
1521                         trace_regulator_disable_complete(rdev_get_name(rdev));
1522
1523                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1524                                              NULL);
1525                 }
1526
1527                 rdev->use_count = 0;
1528         } else if (rdev->use_count > 1) {
1529
1530                 if (rdev->constraints &&
1531                         (rdev->constraints->valid_ops_mask &
1532                         REGULATOR_CHANGE_DRMS))
1533                         drms_uA_update(rdev);
1534
1535                 rdev->use_count--;
1536         }
1537
1538         return ret;
1539 }
1540
1541 /**
1542  * regulator_disable - disable regulator output
1543  * @regulator: regulator source
1544  *
1545  * Disable the regulator output voltage or current.  Calls to
1546  * regulator_enable() must be balanced with calls to
1547  * regulator_disable().
1548  *
1549  * NOTE: this will only disable the regulator output if no other consumer
1550  * devices have it enabled, the regulator device supports disabling and
1551  * machine constraints permit this operation.
1552  */
1553 int regulator_disable(struct regulator *regulator)
1554 {
1555         struct regulator_dev *rdev = regulator->rdev;
1556         int ret = 0;
1557
1558         mutex_lock(&rdev->mutex);
1559         ret = _regulator_disable(rdev);
1560         mutex_unlock(&rdev->mutex);
1561
1562         if (ret == 0 && rdev->supply)
1563                 regulator_disable(rdev->supply);
1564
1565         return ret;
1566 }
1567 EXPORT_SYMBOL_GPL(regulator_disable);
1568
1569 /* locks held by regulator_force_disable() */
1570 static int _regulator_force_disable(struct regulator_dev *rdev)
1571 {
1572         int ret = 0;
1573
1574         /* force disable */
1575         if (rdev->desc->ops->disable) {
1576                 /* ah well, who wants to live forever... */
1577                 ret = rdev->desc->ops->disable(rdev);
1578                 if (ret < 0) {
1579                         rdev_err(rdev, "failed to force disable\n");
1580                         return ret;
1581                 }
1582                 /* notify other consumers that power has been forced off */
1583                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1584                         REGULATOR_EVENT_DISABLE, NULL);
1585         }
1586
1587         return ret;
1588 }
1589
1590 /**
1591  * regulator_force_disable - force disable regulator output
1592  * @regulator: regulator source
1593  *
1594  * Forcibly disable the regulator output voltage or current.
1595  * NOTE: this *will* disable the regulator output even if other consumer
1596  * devices have it enabled. This should be used for situations when device
1597  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1598  */
1599 int regulator_force_disable(struct regulator *regulator)
1600 {
1601         struct regulator_dev *rdev = regulator->rdev;
1602         int ret;
1603
1604         mutex_lock(&rdev->mutex);
1605         regulator->uA_load = 0;
1606         ret = _regulator_force_disable(regulator->rdev);
1607         mutex_unlock(&rdev->mutex);
1608
1609         if (rdev->supply)
1610                 while (rdev->open_count--)
1611                         regulator_disable(rdev->supply);
1612
1613         return ret;
1614 }
1615 EXPORT_SYMBOL_GPL(regulator_force_disable);
1616
1617 static void regulator_disable_work(struct work_struct *work)
1618 {
1619         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
1620                                                   disable_work.work);
1621         int count, i, ret;
1622
1623         mutex_lock(&rdev->mutex);
1624
1625         BUG_ON(!rdev->deferred_disables);
1626
1627         count = rdev->deferred_disables;
1628         rdev->deferred_disables = 0;
1629
1630         for (i = 0; i < count; i++) {
1631                 ret = _regulator_disable(rdev);
1632                 if (ret != 0)
1633                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
1634         }
1635
1636         mutex_unlock(&rdev->mutex);
1637
1638         if (rdev->supply) {
1639                 for (i = 0; i < count; i++) {
1640                         ret = regulator_disable(rdev->supply);
1641                         if (ret != 0) {
1642                                 rdev_err(rdev,
1643                                          "Supply disable failed: %d\n", ret);
1644                         }
1645                 }
1646         }
1647 }
1648
1649 /**
1650  * regulator_disable_deferred - disable regulator output with delay
1651  * @regulator: regulator source
1652  * @ms: miliseconds until the regulator is disabled
1653  *
1654  * Execute regulator_disable() on the regulator after a delay.  This
1655  * is intended for use with devices that require some time to quiesce.
1656  *
1657  * NOTE: this will only disable the regulator output if no other consumer
1658  * devices have it enabled, the regulator device supports disabling and
1659  * machine constraints permit this operation.
1660  */
1661 int regulator_disable_deferred(struct regulator *regulator, int ms)
1662 {
1663         struct regulator_dev *rdev = regulator->rdev;
1664         int ret;
1665
1666         mutex_lock(&rdev->mutex);
1667         rdev->deferred_disables++;
1668         mutex_unlock(&rdev->mutex);
1669
1670         ret = schedule_delayed_work(&rdev->disable_work,
1671                                     msecs_to_jiffies(ms));
1672         if (ret < 0)
1673                 return ret;
1674         else
1675                 return 0;
1676 }
1677 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
1678
1679 static int _regulator_is_enabled(struct regulator_dev *rdev)
1680 {
1681         /* If we don't know then assume that the regulator is always on */
1682         if (!rdev->desc->ops->is_enabled)
1683                 return 1;
1684
1685         return rdev->desc->ops->is_enabled(rdev);
1686 }
1687
1688 /**
1689  * regulator_is_enabled - is the regulator output enabled
1690  * @regulator: regulator source
1691  *
1692  * Returns positive if the regulator driver backing the source/client
1693  * has requested that the device be enabled, zero if it hasn't, else a
1694  * negative errno code.
1695  *
1696  * Note that the device backing this regulator handle can have multiple
1697  * users, so it might be enabled even if regulator_enable() was never
1698  * called for this particular source.
1699  */
1700 int regulator_is_enabled(struct regulator *regulator)
1701 {
1702         int ret;
1703
1704         mutex_lock(&regulator->rdev->mutex);
1705         ret = _regulator_is_enabled(regulator->rdev);
1706         mutex_unlock(&regulator->rdev->mutex);
1707
1708         return ret;
1709 }
1710 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1711
1712 /**
1713  * regulator_count_voltages - count regulator_list_voltage() selectors
1714  * @regulator: regulator source
1715  *
1716  * Returns number of selectors, or negative errno.  Selectors are
1717  * numbered starting at zero, and typically correspond to bitfields
1718  * in hardware registers.
1719  */
1720 int regulator_count_voltages(struct regulator *regulator)
1721 {
1722         struct regulator_dev    *rdev = regulator->rdev;
1723
1724         return rdev->desc->n_voltages ? : -EINVAL;
1725 }
1726 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1727
1728 /**
1729  * regulator_list_voltage - enumerate supported voltages
1730  * @regulator: regulator source
1731  * @selector: identify voltage to list
1732  * Context: can sleep
1733  *
1734  * Returns a voltage that can be passed to @regulator_set_voltage(),
1735  * zero if this selector code can't be used on this system, or a
1736  * negative errno.
1737  */
1738 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1739 {
1740         struct regulator_dev    *rdev = regulator->rdev;
1741         struct regulator_ops    *ops = rdev->desc->ops;
1742         int                     ret;
1743
1744         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1745                 return -EINVAL;
1746
1747         mutex_lock(&rdev->mutex);
1748         ret = ops->list_voltage(rdev, selector);
1749         mutex_unlock(&rdev->mutex);
1750
1751         if (ret > 0) {
1752                 if (ret < rdev->constraints->min_uV)
1753                         ret = 0;
1754                 else if (ret > rdev->constraints->max_uV)
1755                         ret = 0;
1756         }
1757
1758         return ret;
1759 }
1760 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1761
1762 /**
1763  * regulator_is_supported_voltage - check if a voltage range can be supported
1764  *
1765  * @regulator: Regulator to check.
1766  * @min_uV: Minimum required voltage in uV.
1767  * @max_uV: Maximum required voltage in uV.
1768  *
1769  * Returns a boolean or a negative error code.
1770  */
1771 int regulator_is_supported_voltage(struct regulator *regulator,
1772                                    int min_uV, int max_uV)
1773 {
1774         int i, voltages, ret;
1775
1776         ret = regulator_count_voltages(regulator);
1777         if (ret < 0)
1778                 return ret;
1779         voltages = ret;
1780
1781         for (i = 0; i < voltages; i++) {
1782                 ret = regulator_list_voltage(regulator, i);
1783
1784                 if (ret >= min_uV && ret <= max_uV)
1785                         return 1;
1786         }
1787
1788         return 0;
1789 }
1790 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
1791
1792 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
1793                                      int min_uV, int max_uV)
1794 {
1795         int ret;
1796         int delay = 0;
1797         unsigned int selector;
1798
1799         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
1800
1801         min_uV += rdev->constraints->uV_offset;
1802         max_uV += rdev->constraints->uV_offset;
1803
1804         if (rdev->desc->ops->set_voltage) {
1805                 ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
1806                                                    &selector);
1807
1808                 if (rdev->desc->ops->list_voltage)
1809                         selector = rdev->desc->ops->list_voltage(rdev,
1810                                                                  selector);
1811                 else
1812                         selector = -1;
1813         } else if (rdev->desc->ops->set_voltage_sel) {
1814                 int best_val = INT_MAX;
1815                 int i;
1816
1817                 selector = 0;
1818
1819                 /* Find the smallest voltage that falls within the specified
1820                  * range.
1821                  */
1822                 for (i = 0; i < rdev->desc->n_voltages; i++) {
1823                         ret = rdev->desc->ops->list_voltage(rdev, i);
1824                         if (ret < 0)
1825                                 continue;
1826
1827                         if (ret < best_val && ret >= min_uV && ret <= max_uV) {
1828                                 best_val = ret;
1829                                 selector = i;
1830                         }
1831                 }
1832
1833                 /*
1834                  * If we can't obtain the old selector there is not enough
1835                  * info to call set_voltage_time_sel().
1836                  */
1837                 if (rdev->desc->ops->set_voltage_time_sel &&
1838                     rdev->desc->ops->get_voltage_sel) {
1839                         unsigned int old_selector = 0;
1840
1841                         ret = rdev->desc->ops->get_voltage_sel(rdev);
1842                         if (ret < 0)
1843                                 return ret;
1844                         old_selector = ret;
1845                         delay = rdev->desc->ops->set_voltage_time_sel(rdev,
1846                                                 old_selector, selector);
1847                 }
1848
1849                 if (best_val != INT_MAX) {
1850                         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
1851                         selector = best_val;
1852                 } else {
1853                         ret = -EINVAL;
1854                 }
1855         } else {
1856                 ret = -EINVAL;
1857         }
1858
1859         /* Insert any necessary delays */
1860         if (delay >= 1000) {
1861                 mdelay(delay / 1000);
1862                 udelay(delay % 1000);
1863         } else if (delay) {
1864                 udelay(delay);
1865         }
1866
1867         if (ret == 0)
1868                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
1869                                      NULL);
1870
1871         trace_regulator_set_voltage_complete(rdev_get_name(rdev), selector);
1872
1873         return ret;
1874 }
1875
1876 /**
1877  * regulator_set_voltage - set regulator output voltage
1878  * @regulator: regulator source
1879  * @min_uV: Minimum required voltage in uV
1880  * @max_uV: Maximum acceptable voltage in uV
1881  *
1882  * Sets a voltage regulator to the desired output voltage. This can be set
1883  * during any regulator state. IOW, regulator can be disabled or enabled.
1884  *
1885  * If the regulator is enabled then the voltage will change to the new value
1886  * immediately otherwise if the regulator is disabled the regulator will
1887  * output at the new voltage when enabled.
1888  *
1889  * NOTE: If the regulator is shared between several devices then the lowest
1890  * request voltage that meets the system constraints will be used.
1891  * Regulator system constraints must be set for this regulator before
1892  * calling this function otherwise this call will fail.
1893  */
1894 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1895 {
1896         struct regulator_dev *rdev = regulator->rdev;
1897         int ret = 0;
1898
1899         mutex_lock(&rdev->mutex);
1900
1901         /* If we're setting the same range as last time the change
1902          * should be a noop (some cpufreq implementations use the same
1903          * voltage for multiple frequencies, for example).
1904          */
1905         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
1906                 goto out;
1907
1908         /* sanity check */
1909         if (!rdev->desc->ops->set_voltage &&
1910             !rdev->desc->ops->set_voltage_sel) {
1911                 ret = -EINVAL;
1912                 goto out;
1913         }
1914
1915         /* constraints check */
1916         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1917         if (ret < 0)
1918                 goto out;
1919         regulator->min_uV = min_uV;
1920         regulator->max_uV = max_uV;
1921
1922         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
1923         if (ret < 0)
1924                 goto out;
1925
1926         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
1927
1928 out:
1929         mutex_unlock(&rdev->mutex);
1930         return ret;
1931 }
1932 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1933
1934 /**
1935  * regulator_set_voltage_time - get raise/fall time
1936  * @regulator: regulator source
1937  * @old_uV: starting voltage in microvolts
1938  * @new_uV: target voltage in microvolts
1939  *
1940  * Provided with the starting and ending voltage, this function attempts to
1941  * calculate the time in microseconds required to rise or fall to this new
1942  * voltage.
1943  */
1944 int regulator_set_voltage_time(struct regulator *regulator,
1945                                int old_uV, int new_uV)
1946 {
1947         struct regulator_dev    *rdev = regulator->rdev;
1948         struct regulator_ops    *ops = rdev->desc->ops;
1949         int old_sel = -1;
1950         int new_sel = -1;
1951         int voltage;
1952         int i;
1953
1954         /* Currently requires operations to do this */
1955         if (!ops->list_voltage || !ops->set_voltage_time_sel
1956             || !rdev->desc->n_voltages)
1957                 return -EINVAL;
1958
1959         for (i = 0; i < rdev->desc->n_voltages; i++) {
1960                 /* We only look for exact voltage matches here */
1961                 voltage = regulator_list_voltage(regulator, i);
1962                 if (voltage < 0)
1963                         return -EINVAL;
1964                 if (voltage == 0)
1965                         continue;
1966                 if (voltage == old_uV)
1967                         old_sel = i;
1968                 if (voltage == new_uV)
1969                         new_sel = i;
1970         }
1971
1972         if (old_sel < 0 || new_sel < 0)
1973                 return -EINVAL;
1974
1975         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
1976 }
1977 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
1978
1979 /**
1980  * regulator_sync_voltage - re-apply last regulator output voltage
1981  * @regulator: regulator source
1982  *
1983  * Re-apply the last configured voltage.  This is intended to be used
1984  * where some external control source the consumer is cooperating with
1985  * has caused the configured voltage to change.
1986  */
1987 int regulator_sync_voltage(struct regulator *regulator)
1988 {
1989         struct regulator_dev *rdev = regulator->rdev;
1990         int ret, min_uV, max_uV;
1991
1992         mutex_lock(&rdev->mutex);
1993
1994         if (!rdev->desc->ops->set_voltage &&
1995             !rdev->desc->ops->set_voltage_sel) {
1996                 ret = -EINVAL;
1997                 goto out;
1998         }
1999
2000         /* This is only going to work if we've had a voltage configured. */
2001         if (!regulator->min_uV && !regulator->max_uV) {
2002                 ret = -EINVAL;
2003                 goto out;
2004         }
2005
2006         min_uV = regulator->min_uV;
2007         max_uV = regulator->max_uV;
2008
2009         /* This should be a paranoia check... */
2010         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2011         if (ret < 0)
2012                 goto out;
2013
2014         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2015         if (ret < 0)
2016                 goto out;
2017
2018         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2019
2020 out:
2021         mutex_unlock(&rdev->mutex);
2022         return ret;
2023 }
2024 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2025
2026 static int _regulator_get_voltage(struct regulator_dev *rdev)
2027 {
2028         int sel, ret;
2029
2030         if (rdev->desc->ops->get_voltage_sel) {
2031                 sel = rdev->desc->ops->get_voltage_sel(rdev);
2032                 if (sel < 0)
2033                         return sel;
2034                 ret = rdev->desc->ops->list_voltage(rdev, sel);
2035         } else if (rdev->desc->ops->get_voltage) {
2036                 ret = rdev->desc->ops->get_voltage(rdev);
2037         } else {
2038                 return -EINVAL;
2039         }
2040
2041         if (ret < 0)
2042                 return ret;
2043         return ret - rdev->constraints->uV_offset;
2044 }
2045
2046 /**
2047  * regulator_get_voltage - get regulator output voltage
2048  * @regulator: regulator source
2049  *
2050  * This returns the current regulator voltage in uV.
2051  *
2052  * NOTE: If the regulator is disabled it will return the voltage value. This
2053  * function should not be used to determine regulator state.
2054  */
2055 int regulator_get_voltage(struct regulator *regulator)
2056 {
2057         int ret;
2058
2059         mutex_lock(&regulator->rdev->mutex);
2060
2061         ret = _regulator_get_voltage(regulator->rdev);
2062
2063         mutex_unlock(&regulator->rdev->mutex);
2064
2065         return ret;
2066 }
2067 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2068
2069 /**
2070  * regulator_set_current_limit - set regulator output current limit
2071  * @regulator: regulator source
2072  * @min_uA: Minimuum supported current in uA
2073  * @max_uA: Maximum supported current in uA
2074  *
2075  * Sets current sink to the desired output current. This can be set during
2076  * any regulator state. IOW, regulator can be disabled or enabled.
2077  *
2078  * If the regulator is enabled then the current will change to the new value
2079  * immediately otherwise if the regulator is disabled the regulator will
2080  * output at the new current when enabled.
2081  *
2082  * NOTE: Regulator system constraints must be set for this regulator before
2083  * calling this function otherwise this call will fail.
2084  */
2085 int regulator_set_current_limit(struct regulator *regulator,
2086                                int min_uA, int max_uA)
2087 {
2088         struct regulator_dev *rdev = regulator->rdev;
2089         int ret;
2090
2091         mutex_lock(&rdev->mutex);
2092
2093         /* sanity check */
2094         if (!rdev->desc->ops->set_current_limit) {
2095                 ret = -EINVAL;
2096                 goto out;
2097         }
2098
2099         /* constraints check */
2100         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2101         if (ret < 0)
2102                 goto out;
2103
2104         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2105 out:
2106         mutex_unlock(&rdev->mutex);
2107         return ret;
2108 }
2109 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2110
2111 static int _regulator_get_current_limit(struct regulator_dev *rdev)
2112 {
2113         int ret;
2114
2115         mutex_lock(&rdev->mutex);
2116
2117         /* sanity check */
2118         if (!rdev->desc->ops->get_current_limit) {
2119                 ret = -EINVAL;
2120                 goto out;
2121         }
2122
2123         ret = rdev->desc->ops->get_current_limit(rdev);
2124 out:
2125         mutex_unlock(&rdev->mutex);
2126         return ret;
2127 }
2128
2129 /**
2130  * regulator_get_current_limit - get regulator output current
2131  * @regulator: regulator source
2132  *
2133  * This returns the current supplied by the specified current sink in uA.
2134  *
2135  * NOTE: If the regulator is disabled it will return the current value. This
2136  * function should not be used to determine regulator state.
2137  */
2138 int regulator_get_current_limit(struct regulator *regulator)
2139 {
2140         return _regulator_get_current_limit(regulator->rdev);
2141 }
2142 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
2143
2144 /**
2145  * regulator_set_mode - set regulator operating mode
2146  * @regulator: regulator source
2147  * @mode: operating mode - one of the REGULATOR_MODE constants
2148  *
2149  * Set regulator operating mode to increase regulator efficiency or improve
2150  * regulation performance.
2151  *
2152  * NOTE: Regulator system constraints must be set for this regulator before
2153  * calling this function otherwise this call will fail.
2154  */
2155 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2156 {
2157         struct regulator_dev *rdev = regulator->rdev;
2158         int ret;
2159         int regulator_curr_mode;
2160
2161         mutex_lock(&rdev->mutex);
2162
2163         /* sanity check */
2164         if (!rdev->desc->ops->set_mode) {
2165                 ret = -EINVAL;
2166                 goto out;
2167         }
2168
2169         /* return if the same mode is requested */
2170         if (rdev->desc->ops->get_mode) {
2171                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2172                 if (regulator_curr_mode == mode) {
2173                         ret = 0;
2174                         goto out;
2175                 }
2176         }
2177
2178         /* constraints check */
2179         ret = regulator_mode_constrain(rdev, &mode);
2180         if (ret < 0)
2181                 goto out;
2182
2183         ret = rdev->desc->ops->set_mode(rdev, mode);
2184 out:
2185         mutex_unlock(&rdev->mutex);
2186         return ret;
2187 }
2188 EXPORT_SYMBOL_GPL(regulator_set_mode);
2189
2190 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2191 {
2192         int ret;
2193
2194         mutex_lock(&rdev->mutex);
2195
2196         /* sanity check */
2197         if (!rdev->desc->ops->get_mode) {
2198                 ret = -EINVAL;
2199                 goto out;
2200         }
2201
2202         ret = rdev->desc->ops->get_mode(rdev);
2203 out:
2204         mutex_unlock(&rdev->mutex);
2205         return ret;
2206 }
2207
2208 /**
2209  * regulator_get_mode - get regulator operating mode
2210  * @regulator: regulator source
2211  *
2212  * Get the current regulator operating mode.
2213  */
2214 unsigned int regulator_get_mode(struct regulator *regulator)
2215 {
2216         return _regulator_get_mode(regulator->rdev);
2217 }
2218 EXPORT_SYMBOL_GPL(regulator_get_mode);
2219
2220 /**
2221  * regulator_set_optimum_mode - set regulator optimum operating mode
2222  * @regulator: regulator source
2223  * @uA_load: load current
2224  *
2225  * Notifies the regulator core of a new device load. This is then used by
2226  * DRMS (if enabled by constraints) to set the most efficient regulator
2227  * operating mode for the new regulator loading.
2228  *
2229  * Consumer devices notify their supply regulator of the maximum power
2230  * they will require (can be taken from device datasheet in the power
2231  * consumption tables) when they change operational status and hence power
2232  * state. Examples of operational state changes that can affect power
2233  * consumption are :-
2234  *
2235  *    o Device is opened / closed.
2236  *    o Device I/O is about to begin or has just finished.
2237  *    o Device is idling in between work.
2238  *
2239  * This information is also exported via sysfs to userspace.
2240  *
2241  * DRMS will sum the total requested load on the regulator and change
2242  * to the most efficient operating mode if platform constraints allow.
2243  *
2244  * Returns the new regulator mode or error.
2245  */
2246 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
2247 {
2248         struct regulator_dev *rdev = regulator->rdev;
2249         struct regulator *consumer;
2250         int ret, output_uV, input_uV, total_uA_load = 0;
2251         unsigned int mode;
2252
2253         mutex_lock(&rdev->mutex);
2254
2255         /*
2256          * first check to see if we can set modes at all, otherwise just
2257          * tell the consumer everything is OK.
2258          */
2259         regulator->uA_load = uA_load;
2260         ret = regulator_check_drms(rdev);
2261         if (ret < 0) {
2262                 ret = 0;
2263                 goto out;
2264         }
2265
2266         if (!rdev->desc->ops->get_optimum_mode)
2267                 goto out;
2268
2269         /*
2270          * we can actually do this so any errors are indicators of
2271          * potential real failure.
2272          */
2273         ret = -EINVAL;
2274
2275         /* get output voltage */
2276         output_uV = _regulator_get_voltage(rdev);
2277         if (output_uV <= 0) {
2278                 rdev_err(rdev, "invalid output voltage found\n");
2279                 goto out;
2280         }
2281
2282         /* get input voltage */
2283         input_uV = 0;
2284         if (rdev->supply)
2285                 input_uV = regulator_get_voltage(rdev->supply);
2286         if (input_uV <= 0)
2287                 input_uV = rdev->constraints->input_uV;
2288         if (input_uV <= 0) {
2289                 rdev_err(rdev, "invalid input voltage found\n");
2290                 goto out;
2291         }
2292
2293         /* calc total requested load for this regulator */
2294         list_for_each_entry(consumer, &rdev->consumer_list, list)
2295                 total_uA_load += consumer->uA_load;
2296
2297         mode = rdev->desc->ops->get_optimum_mode(rdev,
2298                                                  input_uV, output_uV,
2299                                                  total_uA_load);
2300         ret = regulator_mode_constrain(rdev, &mode);
2301         if (ret < 0) {
2302                 rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
2303                          total_uA_load, input_uV, output_uV);
2304                 goto out;
2305         }
2306
2307         ret = rdev->desc->ops->set_mode(rdev, mode);
2308         if (ret < 0) {
2309                 rdev_err(rdev, "failed to set optimum mode %x\n", mode);
2310                 goto out;
2311         }
2312         ret = mode;
2313 out:
2314         mutex_unlock(&rdev->mutex);
2315         return ret;
2316 }
2317 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
2318
2319 /**
2320  * regulator_register_notifier - register regulator event notifier
2321  * @regulator: regulator source
2322  * @nb: notifier block
2323  *
2324  * Register notifier block to receive regulator events.
2325  */
2326 int regulator_register_notifier(struct regulator *regulator,
2327                               struct notifier_block *nb)
2328 {
2329         return blocking_notifier_chain_register(&regulator->rdev->notifier,
2330                                                 nb);
2331 }
2332 EXPORT_SYMBOL_GPL(regulator_register_notifier);
2333
2334 /**
2335  * regulator_unregister_notifier - unregister regulator event notifier
2336  * @regulator: regulator source
2337  * @nb: notifier block
2338  *
2339  * Unregister regulator event notifier block.
2340  */
2341 int regulator_unregister_notifier(struct regulator *regulator,
2342                                 struct notifier_block *nb)
2343 {
2344         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
2345                                                   nb);
2346 }
2347 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
2348
2349 /* notify regulator consumers and downstream regulator consumers.
2350  * Note mutex must be held by caller.
2351  */
2352 static void _notifier_call_chain(struct regulator_dev *rdev,
2353                                   unsigned long event, void *data)
2354 {
2355         /* call rdev chain first */
2356         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
2357 }
2358
2359 /**
2360  * regulator_bulk_get - get multiple regulator consumers
2361  *
2362  * @dev:           Device to supply
2363  * @num_consumers: Number of consumers to register
2364  * @consumers:     Configuration of consumers; clients are stored here.
2365  *
2366  * @return 0 on success, an errno on failure.
2367  *
2368  * This helper function allows drivers to get several regulator
2369  * consumers in one operation.  If any of the regulators cannot be
2370  * acquired then any regulators that were allocated will be freed
2371  * before returning to the caller.
2372  */
2373 int regulator_bulk_get(struct device *dev, int num_consumers,
2374                        struct regulator_bulk_data *consumers)
2375 {
2376         int i;
2377         int ret;
2378
2379         for (i = 0; i < num_consumers; i++)
2380                 consumers[i].consumer = NULL;
2381
2382         for (i = 0; i < num_consumers; i++) {
2383                 consumers[i].consumer = regulator_get(dev,
2384                                                       consumers[i].supply);
2385                 if (IS_ERR(consumers[i].consumer)) {
2386                         ret = PTR_ERR(consumers[i].consumer);
2387                         dev_err(dev, "Failed to get supply '%s': %d\n",
2388                                 consumers[i].supply, ret);
2389                         consumers[i].consumer = NULL;
2390                         goto err;
2391                 }
2392         }
2393
2394         return 0;
2395
2396 err:
2397         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
2398                 regulator_put(consumers[i].consumer);
2399
2400         return ret;
2401 }
2402 EXPORT_SYMBOL_GPL(regulator_bulk_get);
2403
2404 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
2405 {
2406         struct regulator_bulk_data *bulk = data;
2407
2408         bulk->ret = regulator_enable(bulk->consumer);
2409 }
2410
2411 /**
2412  * regulator_bulk_enable - enable multiple regulator consumers
2413  *
2414  * @num_consumers: Number of consumers
2415  * @consumers:     Consumer data; clients are stored here.
2416  * @return         0 on success, an errno on failure
2417  *
2418  * This convenience API allows consumers to enable multiple regulator
2419  * clients in a single API call.  If any consumers cannot be enabled
2420  * then any others that were enabled will be disabled again prior to
2421  * return.
2422  */
2423 int regulator_bulk_enable(int num_consumers,
2424                           struct regulator_bulk_data *consumers)
2425 {
2426         LIST_HEAD(async_domain);
2427         int i;
2428         int ret = 0;
2429
2430         for (i = 0; i < num_consumers; i++)
2431                 async_schedule_domain(regulator_bulk_enable_async,
2432                                       &consumers[i], &async_domain);
2433
2434         async_synchronize_full_domain(&async_domain);
2435
2436         /* If any consumer failed we need to unwind any that succeeded */
2437         for (i = 0; i < num_consumers; i++) {
2438                 if (consumers[i].ret != 0) {
2439                         ret = consumers[i].ret;
2440                         goto err;
2441                 }
2442         }
2443
2444         return 0;
2445
2446 err:
2447         for (i = 0; i < num_consumers; i++)
2448                 if (consumers[i].ret == 0)
2449                         regulator_disable(consumers[i].consumer);
2450                 else
2451                         pr_err("Failed to enable %s: %d\n",
2452                                consumers[i].supply, consumers[i].ret);
2453
2454         return ret;
2455 }
2456 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2457
2458 /**
2459  * regulator_bulk_disable - disable multiple regulator consumers
2460  *
2461  * @num_consumers: Number of consumers
2462  * @consumers:     Consumer data; clients are stored here.
2463  * @return         0 on success, an errno on failure
2464  *
2465  * This convenience API allows consumers to disable multiple regulator
2466  * clients in a single API call.  If any consumers cannot be enabled
2467  * then any others that were disabled will be disabled again prior to
2468  * return.
2469  */
2470 int regulator_bulk_disable(int num_consumers,
2471                            struct regulator_bulk_data *consumers)
2472 {
2473         int i;
2474         int ret;
2475
2476         for (i = 0; i < num_consumers; i++) {
2477                 ret = regulator_disable(consumers[i].consumer);
2478                 if (ret != 0)
2479                         goto err;
2480         }
2481
2482         return 0;
2483
2484 err:
2485         pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
2486         for (--i; i >= 0; --i)
2487                 regulator_enable(consumers[i].consumer);
2488
2489         return ret;
2490 }
2491 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2492
2493 /**
2494  * regulator_bulk_force_disable - force disable multiple regulator consumers
2495  *
2496  * @num_consumers: Number of consumers
2497  * @consumers:     Consumer data; clients are stored here.
2498  * @return         0 on success, an errno on failure
2499  *
2500  * This convenience API allows consumers to forcibly disable multiple regulator
2501  * clients in a single API call.
2502  * NOTE: This should be used for situations when device damage will
2503  * likely occur if the regulators are not disabled (e.g. over temp).
2504  * Although regulator_force_disable function call for some consumers can
2505  * return error numbers, the function is called for all consumers.
2506  */
2507 int regulator_bulk_force_disable(int num_consumers,
2508                            struct regulator_bulk_data *consumers)
2509 {
2510         int i;
2511         int ret;
2512
2513         for (i = 0; i < num_consumers; i++)
2514                 consumers[i].ret =
2515                             regulator_force_disable(consumers[i].consumer);
2516
2517         for (i = 0; i < num_consumers; i++) {
2518                 if (consumers[i].ret != 0) {
2519                         ret = consumers[i].ret;
2520                         goto out;
2521                 }
2522         }
2523
2524         return 0;
2525 out:
2526         return ret;
2527 }
2528 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
2529
2530 /**
2531  * regulator_bulk_free - free multiple regulator consumers
2532  *
2533  * @num_consumers: Number of consumers
2534  * @consumers:     Consumer data; clients are stored here.
2535  *
2536  * This convenience API allows consumers to free multiple regulator
2537  * clients in a single API call.
2538  */
2539 void regulator_bulk_free(int num_consumers,
2540                          struct regulator_bulk_data *consumers)
2541 {
2542         int i;
2543
2544         for (i = 0; i < num_consumers; i++) {
2545                 regulator_put(consumers[i].consumer);
2546                 consumers[i].consumer = NULL;
2547         }
2548 }
2549 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2550
2551 /**
2552  * regulator_notifier_call_chain - call regulator event notifier
2553  * @rdev: regulator source
2554  * @event: notifier block
2555  * @data: callback-specific data.
2556  *
2557  * Called by regulator drivers to notify clients a regulator event has
2558  * occurred. We also notify regulator clients downstream.
2559  * Note lock must be held by caller.
2560  */
2561 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2562                                   unsigned long event, void *data)
2563 {
2564         _notifier_call_chain(rdev, event, data);
2565         return NOTIFY_DONE;
2566
2567 }
2568 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2569
2570 /**
2571  * regulator_mode_to_status - convert a regulator mode into a status
2572  *
2573  * @mode: Mode to convert
2574  *
2575  * Convert a regulator mode into a status.
2576  */
2577 int regulator_mode_to_status(unsigned int mode)
2578 {
2579         switch (mode) {
2580         case REGULATOR_MODE_FAST:
2581                 return REGULATOR_STATUS_FAST;
2582         case REGULATOR_MODE_NORMAL:
2583                 return REGULATOR_STATUS_NORMAL;
2584         case REGULATOR_MODE_IDLE:
2585                 return REGULATOR_STATUS_IDLE;
2586         case REGULATOR_STATUS_STANDBY:
2587                 return REGULATOR_STATUS_STANDBY;
2588         default:
2589                 return 0;
2590         }
2591 }
2592 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2593
2594 /*
2595  * To avoid cluttering sysfs (and memory) with useless state, only
2596  * create attributes that can be meaningfully displayed.
2597  */
2598 static int add_regulator_attributes(struct regulator_dev *rdev)
2599 {
2600         struct device           *dev = &rdev->dev;
2601         struct regulator_ops    *ops = rdev->desc->ops;
2602         int                     status = 0;
2603
2604         /* some attributes need specific methods to be displayed */
2605         if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
2606             (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0)) {
2607                 status = device_create_file(dev, &dev_attr_microvolts);
2608                 if (status < 0)
2609                         return status;
2610         }
2611         if (ops->get_current_limit) {
2612                 status = device_create_file(dev, &dev_attr_microamps);
2613                 if (status < 0)
2614                         return status;
2615         }
2616         if (ops->get_mode) {
2617                 status = device_create_file(dev, &dev_attr_opmode);
2618                 if (status < 0)
2619                         return status;
2620         }
2621         if (ops->is_enabled) {
2622                 status = device_create_file(dev, &dev_attr_state);
2623                 if (status < 0)
2624                         return status;
2625         }
2626         if (ops->get_status) {
2627                 status = device_create_file(dev, &dev_attr_status);
2628                 if (status < 0)
2629                         return status;
2630         }
2631
2632         /* some attributes are type-specific */
2633         if (rdev->desc->type == REGULATOR_CURRENT) {
2634                 status = device_create_file(dev, &dev_attr_requested_microamps);
2635                 if (status < 0)
2636                         return status;
2637         }
2638
2639         /* all the other attributes exist to support constraints;
2640          * don't show them if there are no constraints, or if the
2641          * relevant supporting methods are missing.
2642          */
2643         if (!rdev->constraints)
2644                 return status;
2645
2646         /* constraints need specific supporting methods */
2647         if (ops->set_voltage || ops->set_voltage_sel) {
2648                 status = device_create_file(dev, &dev_attr_min_microvolts);
2649                 if (status < 0)
2650                         return status;
2651                 status = device_create_file(dev, &dev_attr_max_microvolts);
2652                 if (status < 0)
2653                         return status;
2654         }
2655         if (ops->set_current_limit) {
2656                 status = device_create_file(dev, &dev_attr_min_microamps);
2657                 if (status < 0)
2658                         return status;
2659                 status = device_create_file(dev, &dev_attr_max_microamps);
2660                 if (status < 0)
2661                         return status;
2662         }
2663
2664         /* suspend mode constraints need multiple supporting methods */
2665         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2666                 return status;
2667
2668         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2669         if (status < 0)
2670                 return status;
2671         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2672         if (status < 0)
2673                 return status;
2674         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2675         if (status < 0)
2676                 return status;
2677
2678         if (ops->set_suspend_voltage) {
2679                 status = device_create_file(dev,
2680                                 &dev_attr_suspend_standby_microvolts);
2681                 if (status < 0)
2682                         return status;
2683                 status = device_create_file(dev,
2684                                 &dev_attr_suspend_mem_microvolts);
2685                 if (status < 0)
2686                         return status;
2687                 status = device_create_file(dev,
2688                                 &dev_attr_suspend_disk_microvolts);
2689                 if (status < 0)
2690                         return status;
2691         }
2692
2693         if (ops->set_suspend_mode) {
2694                 status = device_create_file(dev,
2695                                 &dev_attr_suspend_standby_mode);
2696                 if (status < 0)
2697                         return status;
2698                 status = device_create_file(dev,
2699                                 &dev_attr_suspend_mem_mode);
2700                 if (status < 0)
2701                         return status;
2702                 status = device_create_file(dev,
2703                                 &dev_attr_suspend_disk_mode);
2704                 if (status < 0)
2705                         return status;
2706         }
2707
2708         return status;
2709 }
2710
2711 static void rdev_init_debugfs(struct regulator_dev *rdev)
2712 {
2713 #ifdef CONFIG_DEBUG_FS
2714         rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
2715         if (IS_ERR(rdev->debugfs) || !rdev->debugfs) {
2716                 rdev_warn(rdev, "Failed to create debugfs directory\n");
2717                 rdev->debugfs = NULL;
2718                 return;
2719         }
2720
2721         debugfs_create_u32("use_count", 0444, rdev->debugfs,
2722                            &rdev->use_count);
2723         debugfs_create_u32("open_count", 0444, rdev->debugfs,
2724                            &rdev->open_count);
2725 #endif
2726 }
2727
2728 /**
2729  * regulator_register - register regulator
2730  * @regulator_desc: regulator to register
2731  * @dev: struct device for the regulator
2732  * @init_data: platform provided init data, passed through by driver
2733  * @driver_data: private regulator data
2734  *
2735  * Called by regulator drivers to register a regulator.
2736  * Returns 0 on success.
2737  */
2738 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2739         struct device *dev, const struct regulator_init_data *init_data,
2740         void *driver_data, struct device_node *of_node)
2741 {
2742         const struct regulation_constraints *constraints = NULL;
2743         static atomic_t regulator_no = ATOMIC_INIT(0);
2744         struct regulator_dev *rdev;
2745         int ret, i;
2746         const char *supply = NULL;
2747
2748         if (regulator_desc == NULL)
2749                 return ERR_PTR(-EINVAL);
2750
2751         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2752                 return ERR_PTR(-EINVAL);
2753
2754         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2755             regulator_desc->type != REGULATOR_CURRENT)
2756                 return ERR_PTR(-EINVAL);
2757
2758         /* Only one of each should be implemented */
2759         WARN_ON(regulator_desc->ops->get_voltage &&
2760                 regulator_desc->ops->get_voltage_sel);
2761         WARN_ON(regulator_desc->ops->set_voltage &&
2762                 regulator_desc->ops->set_voltage_sel);
2763
2764         /* If we're using selectors we must implement list_voltage. */
2765         if (regulator_desc->ops->get_voltage_sel &&
2766             !regulator_desc->ops->list_voltage) {
2767                 return ERR_PTR(-EINVAL);
2768         }
2769         if (regulator_desc->ops->set_voltage_sel &&
2770             !regulator_desc->ops->list_voltage) {
2771                 return ERR_PTR(-EINVAL);
2772         }
2773
2774         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2775         if (rdev == NULL)
2776                 return ERR_PTR(-ENOMEM);
2777
2778         mutex_lock(&regulator_list_mutex);
2779
2780         mutex_init(&rdev->mutex);
2781         rdev->reg_data = driver_data;
2782         rdev->owner = regulator_desc->owner;
2783         rdev->desc = regulator_desc;
2784         INIT_LIST_HEAD(&rdev->consumer_list);
2785         INIT_LIST_HEAD(&rdev->list);
2786         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2787         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
2788
2789         /* preform any regulator specific init */
2790         if (init_data && init_data->regulator_init) {
2791                 ret = init_data->regulator_init(rdev->reg_data);
2792                 if (ret < 0)
2793                         goto clean;
2794         }
2795
2796         /* register with sysfs */
2797         rdev->dev.class = &regulator_class;
2798         rdev->dev.of_node = of_node;
2799         rdev->dev.parent = dev;
2800         dev_set_name(&rdev->dev, "regulator.%d",
2801                      atomic_inc_return(&regulator_no) - 1);
2802         ret = device_register(&rdev->dev);
2803         if (ret != 0) {
2804                 put_device(&rdev->dev);
2805                 goto clean;
2806         }
2807
2808         dev_set_drvdata(&rdev->dev, rdev);
2809
2810         /* set regulator constraints */
2811         if (init_data)
2812                 constraints = &init_data->constraints;
2813
2814         ret = set_machine_constraints(rdev, constraints);
2815         if (ret < 0)
2816                 goto scrub;
2817
2818         /* add attributes supported by this regulator */
2819         ret = add_regulator_attributes(rdev);
2820         if (ret < 0)
2821                 goto scrub;
2822
2823         if (init_data && init_data->supply_regulator)
2824                 supply = init_data->supply_regulator;
2825         else if (regulator_desc->supply_name)
2826                 supply = regulator_desc->supply_name;
2827
2828         if (supply) {
2829                 struct regulator_dev *r;
2830
2831                 r = regulator_dev_lookup(dev, supply);
2832
2833                 if (!r) {
2834                         dev_err(dev, "Failed to find supply %s\n", supply);
2835                         ret = -ENODEV;
2836                         goto scrub;
2837                 }
2838
2839                 ret = set_supply(rdev, r);
2840                 if (ret < 0)
2841                         goto scrub;
2842
2843                 /* Enable supply if rail is enabled */
2844                 if (rdev->desc->ops->is_enabled &&
2845                                 rdev->desc->ops->is_enabled(rdev)) {
2846                         ret = regulator_enable(rdev->supply);
2847                         if (ret < 0)
2848                                 goto scrub;
2849                 }
2850         }
2851
2852         /* add consumers devices */
2853         if (init_data) {
2854                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
2855                         ret = set_consumer_device_supply(rdev,
2856                                 init_data->consumer_supplies[i].dev,
2857                                 init_data->consumer_supplies[i].dev_name,
2858                                 init_data->consumer_supplies[i].supply);
2859                         if (ret < 0) {
2860                                 dev_err(dev, "Failed to set supply %s\n",
2861                                         init_data->consumer_supplies[i].supply);
2862                                 goto unset_supplies;
2863                         }
2864                 }
2865         }
2866
2867         list_add(&rdev->list, &regulator_list);
2868
2869         rdev_init_debugfs(rdev);
2870 out:
2871         mutex_unlock(&regulator_list_mutex);
2872         return rdev;
2873
2874 unset_supplies:
2875         unset_regulator_supplies(rdev);
2876
2877 scrub:
2878         kfree(rdev->constraints);
2879         device_unregister(&rdev->dev);
2880         /* device core frees rdev */
2881         rdev = ERR_PTR(ret);
2882         goto out;
2883
2884 clean:
2885         kfree(rdev);
2886         rdev = ERR_PTR(ret);
2887         goto out;
2888 }
2889 EXPORT_SYMBOL_GPL(regulator_register);
2890
2891 /**
2892  * regulator_unregister - unregister regulator
2893  * @rdev: regulator to unregister
2894  *
2895  * Called by regulator drivers to unregister a regulator.
2896  */
2897 void regulator_unregister(struct regulator_dev *rdev)
2898 {
2899         if (rdev == NULL)
2900                 return;
2901
2902         mutex_lock(&regulator_list_mutex);
2903 #ifdef CONFIG_DEBUG_FS
2904         debugfs_remove_recursive(rdev->debugfs);
2905 #endif
2906         flush_work_sync(&rdev->disable_work.work);
2907         WARN_ON(rdev->open_count);
2908         unset_regulator_supplies(rdev);
2909         list_del(&rdev->list);
2910         if (rdev->supply)
2911                 regulator_put(rdev->supply);
2912         kfree(rdev->constraints);
2913         device_unregister(&rdev->dev);
2914         mutex_unlock(&regulator_list_mutex);
2915 }
2916 EXPORT_SYMBOL_GPL(regulator_unregister);
2917
2918 /**
2919  * regulator_suspend_prepare - prepare regulators for system wide suspend
2920  * @state: system suspend state
2921  *
2922  * Configure each regulator with it's suspend operating parameters for state.
2923  * This will usually be called by machine suspend code prior to supending.
2924  */
2925 int regulator_suspend_prepare(suspend_state_t state)
2926 {
2927         struct regulator_dev *rdev;
2928         int ret = 0;
2929
2930         /* ON is handled by regulator active state */
2931         if (state == PM_SUSPEND_ON)
2932                 return -EINVAL;
2933
2934         mutex_lock(&regulator_list_mutex);
2935         list_for_each_entry(rdev, &regulator_list, list) {
2936
2937                 mutex_lock(&rdev->mutex);
2938                 ret = suspend_prepare(rdev, state);
2939                 mutex_unlock(&rdev->mutex);
2940
2941                 if (ret < 0) {
2942                         rdev_err(rdev, "failed to prepare\n");
2943                         goto out;
2944                 }
2945         }
2946 out:
2947         mutex_unlock(&regulator_list_mutex);
2948         return ret;
2949 }
2950 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2951
2952 /**
2953  * regulator_suspend_finish - resume regulators from system wide suspend
2954  *
2955  * Turn on regulators that might be turned off by regulator_suspend_prepare
2956  * and that should be turned on according to the regulators properties.
2957  */
2958 int regulator_suspend_finish(void)
2959 {
2960         struct regulator_dev *rdev;
2961         int ret = 0, error;
2962
2963         mutex_lock(&regulator_list_mutex);
2964         list_for_each_entry(rdev, &regulator_list, list) {
2965                 struct regulator_ops *ops = rdev->desc->ops;
2966
2967                 mutex_lock(&rdev->mutex);
2968                 if ((rdev->use_count > 0  || rdev->constraints->always_on) &&
2969                                 ops->enable) {
2970                         error = ops->enable(rdev);
2971                         if (error)
2972                                 ret = error;
2973                 } else {
2974                         if (!has_full_constraints)
2975                                 goto unlock;
2976                         if (!ops->disable)
2977                                 goto unlock;
2978                         if (ops->is_enabled && !ops->is_enabled(rdev))
2979                                 goto unlock;
2980
2981                         error = ops->disable(rdev);
2982                         if (error)
2983                                 ret = error;
2984                 }
2985 unlock:
2986                 mutex_unlock(&rdev->mutex);
2987         }
2988         mutex_unlock(&regulator_list_mutex);
2989         return ret;
2990 }
2991 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
2992
2993 /**
2994  * regulator_has_full_constraints - the system has fully specified constraints
2995  *
2996  * Calling this function will cause the regulator API to disable all
2997  * regulators which have a zero use count and don't have an always_on
2998  * constraint in a late_initcall.
2999  *
3000  * The intention is that this will become the default behaviour in a
3001  * future kernel release so users are encouraged to use this facility
3002  * now.
3003  */
3004 void regulator_has_full_constraints(void)
3005 {
3006         has_full_constraints = 1;
3007 }
3008 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3009
3010 /**
3011  * regulator_use_dummy_regulator - Provide a dummy regulator when none is found
3012  *
3013  * Calling this function will cause the regulator API to provide a
3014  * dummy regulator to consumers if no physical regulator is found,
3015  * allowing most consumers to proceed as though a regulator were
3016  * configured.  This allows systems such as those with software
3017  * controllable regulators for the CPU core only to be brought up more
3018  * readily.
3019  */
3020 void regulator_use_dummy_regulator(void)
3021 {
3022         board_wants_dummy_regulator = true;
3023 }
3024 EXPORT_SYMBOL_GPL(regulator_use_dummy_regulator);
3025
3026 /**
3027  * rdev_get_drvdata - get rdev regulator driver data
3028  * @rdev: regulator
3029  *
3030  * Get rdev regulator driver private data. This call can be used in the
3031  * regulator driver context.
3032  */
3033 void *rdev_get_drvdata(struct regulator_dev *rdev)
3034 {
3035         return rdev->reg_data;
3036 }
3037 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3038
3039 /**
3040  * regulator_get_drvdata - get regulator driver data
3041  * @regulator: regulator
3042  *
3043  * Get regulator driver private data. This call can be used in the consumer
3044  * driver context when non API regulator specific functions need to be called.
3045  */
3046 void *regulator_get_drvdata(struct regulator *regulator)
3047 {
3048         return regulator->rdev->reg_data;
3049 }
3050 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3051
3052 /**
3053  * regulator_set_drvdata - set regulator driver data
3054  * @regulator: regulator
3055  * @data: data
3056  */
3057 void regulator_set_drvdata(struct regulator *regulator, void *data)
3058 {
3059         regulator->rdev->reg_data = data;
3060 }
3061 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3062
3063 /**
3064  * regulator_get_id - get regulator ID
3065  * @rdev: regulator
3066  */
3067 int rdev_get_id(struct regulator_dev *rdev)
3068 {
3069         return rdev->desc->id;
3070 }
3071 EXPORT_SYMBOL_GPL(rdev_get_id);
3072
3073 struct device *rdev_get_dev(struct regulator_dev *rdev)
3074 {
3075         return &rdev->dev;
3076 }
3077 EXPORT_SYMBOL_GPL(rdev_get_dev);
3078
3079 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
3080 {
3081         return reg_init_data->driver_data;
3082 }
3083 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
3084
3085 #ifdef CONFIG_DEBUG_FS
3086 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
3087                                     size_t count, loff_t *ppos)
3088 {
3089         char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
3090         ssize_t len, ret = 0;
3091         struct regulator_map *map;
3092
3093         if (!buf)
3094                 return -ENOMEM;
3095
3096         list_for_each_entry(map, &regulator_map_list, list) {
3097                 len = snprintf(buf + ret, PAGE_SIZE - ret,
3098                                "%s -> %s.%s\n",
3099                                rdev_get_name(map->regulator), map->dev_name,
3100                                map->supply);
3101                 if (len >= 0)
3102                         ret += len;
3103                 if (ret > PAGE_SIZE) {
3104                         ret = PAGE_SIZE;
3105                         break;
3106                 }
3107         }
3108
3109         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
3110
3111         kfree(buf);
3112
3113         return ret;
3114 }
3115
3116 static const struct file_operations supply_map_fops = {
3117         .read = supply_map_read_file,
3118         .llseek = default_llseek,
3119 };
3120 #endif
3121
3122 static int __init regulator_init(void)
3123 {
3124         int ret;
3125
3126         ret = class_register(&regulator_class);
3127
3128 #ifdef CONFIG_DEBUG_FS
3129         debugfs_root = debugfs_create_dir("regulator", NULL);
3130         if (IS_ERR(debugfs_root) || !debugfs_root) {
3131                 pr_warn("regulator: Failed to create debugfs directory\n");
3132                 debugfs_root = NULL;
3133         }
3134
3135         if (IS_ERR(debugfs_create_file("supply_map", 0444, debugfs_root,
3136                                        NULL, &supply_map_fops)))
3137                 pr_warn("regulator: Failed to create supplies debugfs\n");
3138 #endif
3139
3140         regulator_dummy_init();
3141
3142         return ret;
3143 }
3144
3145 /* init early to allow our consumers to complete system booting */
3146 core_initcall(regulator_init);
3147
3148 static int __init regulator_init_complete(void)
3149 {
3150         struct regulator_dev *rdev;
3151         struct regulator_ops *ops;
3152         struct regulation_constraints *c;
3153         int enabled, ret;
3154
3155         mutex_lock(&regulator_list_mutex);
3156
3157         /* If we have a full configuration then disable any regulators
3158          * which are not in use or always_on.  This will become the
3159          * default behaviour in the future.
3160          */
3161         list_for_each_entry(rdev, &regulator_list, list) {
3162                 ops = rdev->desc->ops;
3163                 c = rdev->constraints;
3164
3165                 if (!ops->disable || (c && c->always_on))
3166                         continue;
3167
3168                 mutex_lock(&rdev->mutex);
3169
3170                 if (rdev->use_count)
3171                         goto unlock;
3172
3173                 /* If we can't read the status assume it's on. */
3174                 if (ops->is_enabled)
3175                         enabled = ops->is_enabled(rdev);
3176                 else
3177                         enabled = 1;
3178
3179                 if (!enabled)
3180                         goto unlock;
3181
3182                 if (has_full_constraints) {
3183                         /* We log since this may kill the system if it
3184                          * goes wrong. */
3185                         rdev_info(rdev, "disabling\n");
3186                         ret = ops->disable(rdev);
3187                         if (ret != 0) {
3188                                 rdev_err(rdev, "couldn't disable: %d\n", ret);
3189                         }
3190                 } else {
3191                         /* The intention is that in future we will
3192                          * assume that full constraints are provided
3193                          * so warn even if we aren't going to do
3194                          * anything here.
3195                          */
3196                         rdev_warn(rdev, "incomplete constraints, leaving on\n");
3197                 }
3198
3199 unlock:
3200                 mutex_unlock(&rdev->mutex);
3201         }
3202
3203         mutex_unlock(&regulator_list_mutex);
3204
3205         return 0;
3206 }
3207 late_initcall(regulator_init_complete);