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