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