drivers/regulator/core.c

   1 /*
   2  * core.c  --  Voltage/Current Regulator framework.
   3  *
   4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
   5  * Copyright 2008 SlimLogic Ltd.
   6  *
   7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
   8  *
   9  *  This program is free software; you can redistribute  it and/or modify it
  10  *  under  the terms of  the GNU General  Public License as published by the
  11  *  Free Software Foundation;  either version 2 of the  License, or (at your
  12  *  option) any later version.
  13  *
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/debugfs.h>
  19 #include <linux/device.h>
  20 #include <linux/slab.h>
  21 #include <linux/async.h>
  22 #include <linux/err.h>
  23 #include <linux/mutex.h>
  24 #include <linux/suspend.h>
  25 #include <linux/delay.h>
  26 #include <linux/gpio.h>
  27 #include <linux/of.h>
  28 #include <linux/regmap.h>
  29 #include <linux/regulator/of_regulator.h>
  30 #include <linux/regulator/consumer.h>
  31 #include <linux/regulator/driver.h>
  32 #include <linux/regulator/machine.h>
  33 #include <linux/module.h>
  34
  35 #define CREATE_TRACE_POINTS
  36 #include <trace/events/regulator.h>
  37
  38 #include "dummy.h"
  39 #include "internal.h"
  40
  41 #define rdev_crit(rdev, fmt, ...)                                       \
  42         pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  43 #define rdev_err(rdev, fmt, ...)                                        \
  44         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  45 #define rdev_warn(rdev, fmt, ...)                                       \
  46         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  47 #define rdev_info(rdev, fmt, ...)                                       \
  48         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  49 #define rdev_dbg(rdev, fmt, ...)                                        \
  50         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  51
  52 static DEFINE_MUTEX(regulator_list_mutex);
  53 static LIST_HEAD(regulator_list);
  54 static LIST_HEAD(regulator_map_list);
  55 static LIST_HEAD(regulator_ena_gpio_list);
  56 static LIST_HEAD(regulator_supply_alias_list);
  57 static bool has_full_constraints;
  58 static bool board_wants_dummy_regulator;
  59
  60 static struct dentry *debugfs_root;
  61
  62 /*
  63  * struct regulator_map
  64  *
  65  * Used to provide symbolic supply names to devices.
  66  */
  67 struct regulator_map {
  68         struct list_head list;
  69         const char *dev_name;   /* The dev_name() for the consumer */
  70         const char *supply;
  71         struct regulator_dev *regulator;
  72 };
  73
  74 /*
  75  * struct regulator_enable_gpio
  76  *
  77  * Management for shared enable GPIO pin
  78  */
  79 struct regulator_enable_gpio {
  80         struct list_head list;
  81         int gpio;
  82         u32 enable_count;       /* a number of enabled shared GPIO */
  83         u32 request_count;      /* a number of requested shared GPIO */
  84         unsigned int ena_gpio_invert:1;
  85 };
  86
  87 /*
  88  * struct regulator_supply_alias
  89  *
  90  * Used to map lookups for a supply onto an alternative device.
  91  */
  92 struct regulator_supply_alias {
  93         struct list_head list;
  94         struct device *src_dev;
  95         const char *src_supply;
  96         struct device *alias_dev;
  97         const char *alias_supply;
  98 };
  99
 100 static int _regulator_is_enabled(struct regulator_dev *rdev);
 101 static int _regulator_disable(struct regulator_dev *rdev);
 102 static int _regulator_get_voltage(struct regulator_dev *rdev);
 103 static int _regulator_get_current_limit(struct regulator_dev *rdev);
 104 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
 105 static void _notifier_call_chain(struct regulator_dev *rdev,
 106                                   unsigned long event, void *data);
 107 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
 108                                      int min_uV, int max_uV);
 109 static struct regulator *create_regulator(struct regulator_dev *rdev,
 110                                           struct device *dev,
 111                                           const char *supply_name);
 112
 113 static const char *rdev_get_name(struct regulator_dev *rdev)
 114 {
 115         if (rdev->constraints && rdev->constraints->name)
 116                 return rdev->constraints->name;
 117         else if (rdev->desc->name)
 118                 return rdev->desc->name;
 119         else
 120                 return "";
 121 }
 122
 123 /**
 124  * of_get_regulator - get a regulator device node based on supply name
 125  * @dev: Device pointer for the consumer (of regulator) device
 126  * @supply: regulator supply name
 127  *
 128  * Extract the regulator device node corresponding to the supply name.
 129  * returns the device node corresponding to the regulator if found, else
 130  * returns NULL.
 131  */
 132 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 133 {
 134         struct device_node *regnode = NULL;
 135         char prop_name[32]; /* 32 is max size of property name */
 136
 137         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 138
 139         snprintf(prop_name, 32, "%s-supply", supply);
 140         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 141
 142         if (!regnode) {
 143                 dev_dbg(dev, "Looking up %s property in node %s failed",
 144                                 prop_name, dev->of_node->full_name);
 145                 return NULL;
 146         }
 147         return regnode;
 148 }
 149
 150 static int _regulator_can_change_status(struct regulator_dev *rdev)
 151 {
 152         if (!rdev->constraints)
 153                 return 0;
 154
 155         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
 156                 return 1;
 157         else
 158                 return 0;
 159 }
 160
 161 /* Platform voltage constraint check */
 162 static int regulator_check_voltage(struct regulator_dev *rdev,
 163                                    int *min_uV, int *max_uV)
 164 {
 165         BUG_ON(*min_uV > *max_uV);
 166
 167         if (!rdev->constraints) {
 168                 rdev_err(rdev, "no constraints\n");
 169                 return -ENODEV;
 170         }
 171         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 172                 rdev_err(rdev, "operation not allowed\n");
 173                 return -EPERM;
 174         }
 175
 176         if (*max_uV > rdev->constraints->max_uV)
 177                 *max_uV = rdev->constraints->max_uV;
 178         if (*min_uV < rdev->constraints->min_uV)
 179                 *min_uV = rdev->constraints->min_uV;
 180
 181         if (*min_uV > *max_uV) {
 182                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 183                          *min_uV, *max_uV);
 184                 return -EINVAL;
 185         }
 186
 187         return 0;
 188 }
 189
 190 /* Make sure we select a voltage that suits the needs of all
 191  * regulator consumers
 192  */
 193 static int regulator_check_consumers(struct regulator_dev *rdev,
 194                                      int *min_uV, int *max_uV)
 195 {
 196         struct regulator *regulator;
 197
 198         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 199                 /*
 200                  * Assume consumers that didn't say anything are OK
 201                  * with anything in the constraint range.
 202                  */
 203                 if (!regulator->min_uV && !regulator->max_uV)
 204                         continue;
 205
 206                 if (*max_uV > regulator->max_uV)
 207                         *max_uV = regulator->max_uV;
 208                 if (*min_uV < regulator->min_uV)
 209                         *min_uV = regulator->min_uV;
 210         }
 211
 212         if (*min_uV > *max_uV) {
 213                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
 214                         *min_uV, *max_uV);
 215                 return -EINVAL;
 216         }
 217
 218         return 0;
 219 }
 220
 221 /* current constraint check */
 222 static int regulator_check_current_limit(struct regulator_dev *rdev,
 223                                         int *min_uA, int *max_uA)
 224 {
 225         BUG_ON(*min_uA > *max_uA);
 226
 227         if (!rdev->constraints) {
 228                 rdev_err(rdev, "no constraints\n");
 229                 return -ENODEV;
 230         }
 231         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 232                 rdev_err(rdev, "operation not allowed\n");
 233                 return -EPERM;
 234         }
 235
 236         if (*max_uA > rdev->constraints->max_uA)
 237                 *max_uA = rdev->constraints->max_uA;
 238         if (*min_uA < rdev->constraints->min_uA)
 239                 *min_uA = rdev->constraints->min_uA;
 240
 241         if (*min_uA > *max_uA) {
 242                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 243                          *min_uA, *max_uA);
 244                 return -EINVAL;
 245         }
 246
 247         return 0;
 248 }
 249
 250 /* operating mode constraint check */
 251 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
 252 {
 253         switch (*mode) {
 254         case REGULATOR_MODE_FAST:
 255         case REGULATOR_MODE_NORMAL:
 256         case REGULATOR_MODE_IDLE:
 257         case REGULATOR_MODE_STANDBY:
 258                 break;
 259         default:
 260                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 261                 return -EINVAL;
 262         }
 263
 264         if (!rdev->constraints) {
 265                 rdev_err(rdev, "no constraints\n");
 266                 return -ENODEV;
 267         }
 268         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 269                 rdev_err(rdev, "operation not allowed\n");
 270                 return -EPERM;
 271         }
 272
 273         /* The modes are bitmasks, the most power hungry modes having
 274          * the lowest values. If the requested mode isn't supported
 275          * try higher modes. */
 276         while (*mode) {
 277                 if (rdev->constraints->valid_modes_mask & *mode)
 278                         return 0;
 279                 *mode /= 2;
 280         }
 281
 282         return -EINVAL;
 283 }
 284
 285 /* dynamic regulator mode switching constraint check */
 286 static int regulator_check_drms(struct regulator_dev *rdev)
 287 {
 288         if (!rdev->constraints) {
 289                 rdev_err(rdev, "no constraints\n");
 290                 return -ENODEV;
 291         }
 292         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 293                 rdev_err(rdev, "operation not allowed\n");
 294                 return -EPERM;
 295         }
 296         return 0;
 297 }
 298
 299 static ssize_t regulator_uV_show(struct device *dev,
 300                                 struct device_attribute *attr, char *buf)
 301 {
 302         struct regulator_dev *rdev = dev_get_drvdata(dev);
 303         ssize_t ret;
 304
 305         mutex_lock(&rdev->mutex);
 306         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 307         mutex_unlock(&rdev->mutex);
 308
 309         return ret;
 310 }
 311 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 312
 313 static ssize_t regulator_uA_show(struct device *dev,
 314                                 struct device_attribute *attr, char *buf)
 315 {
 316         struct regulator_dev *rdev = dev_get_drvdata(dev);
 317
 318         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 319 }
 320 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 321
 322 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 323                          char *buf)
 324 {
 325         struct regulator_dev *rdev = dev_get_drvdata(dev);
 326
 327         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 328 }
 329 static DEVICE_ATTR_RO(name);
 330
 331 static ssize_t regulator_print_opmode(char *buf, int mode)
 332 {
 333         switch (mode) {
 334         case REGULATOR_MODE_FAST:
 335                 return sprintf(buf, "fast\n");
 336         case REGULATOR_MODE_NORMAL:
 337                 return sprintf(buf, "normal\n");
 338         case REGULATOR_MODE_IDLE:
 339                 return sprintf(buf, "idle\n");
 340         case REGULATOR_MODE_STANDBY:
 341                 return sprintf(buf, "standby\n");
 342         }
 343         return sprintf(buf, "unknown\n");
 344 }
 345
 346 static ssize_t regulator_opmode_show(struct device *dev,
 347                                     struct device_attribute *attr, char *buf)
 348 {
 349         struct regulator_dev *rdev = dev_get_drvdata(dev);
 350
 351         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 352 }
 353 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 354
 355 static ssize_t regulator_print_state(char *buf, int state)
 356 {
 357         if (state > 0)
 358                 return sprintf(buf, "enabled\n");
 359         else if (state == 0)
 360                 return sprintf(buf, "disabled\n");
 361         else
 362                 return sprintf(buf, "unknown\n");
 363 }
 364
 365 static ssize_t regulator_state_show(struct device *dev,
 366                                    struct device_attribute *attr, char *buf)
 367 {
 368         struct regulator_dev *rdev = dev_get_drvdata(dev);
 369         ssize_t ret;
 370
 371         mutex_lock(&rdev->mutex);
 372         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 373         mutex_unlock(&rdev->mutex);
 374
 375         return ret;
 376 }
 377 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 378
 379 static ssize_t regulator_status_show(struct device *dev,
 380                                    struct device_attribute *attr, char *buf)
 381 {
 382         struct regulator_dev *rdev = dev_get_drvdata(dev);
 383         int status;
 384         char *label;
 385
 386         status = rdev->desc->ops->get_status(rdev);
 387         if (status < 0)
 388                 return status;
 389
 390         switch (status) {
 391         case REGULATOR_STATUS_OFF:
 392                 label = "off";
 393                 break;
 394         case REGULATOR_STATUS_ON:
 395                 label = "on";
 396                 break;
 397         case REGULATOR_STATUS_ERROR:
 398                 label = "error";
 399                 break;
 400         case REGULATOR_STATUS_FAST:
 401                 label = "fast";
 402                 break;
 403         case REGULATOR_STATUS_NORMAL:
 404                 label = "normal";
 405                 break;
 406         case REGULATOR_STATUS_IDLE:
 407                 label = "idle";
 408                 break;
 409         case REGULATOR_STATUS_STANDBY:
 410                 label = "standby";
 411                 break;
 412         case REGULATOR_STATUS_BYPASS:
 413                 label = "bypass";
 414                 break;
 415         case REGULATOR_STATUS_UNDEFINED:
 416                 label = "undefined";
 417                 break;
 418         default:
 419                 return -ERANGE;
 420         }
 421
 422         return sprintf(buf, "%s\n", label);
 423 }
 424 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 425
 426 static ssize_t regulator_min_uA_show(struct device *dev,
 427                                     struct device_attribute *attr, char *buf)
 428 {
 429         struct regulator_dev *rdev = dev_get_drvdata(dev);
 430
 431         if (!rdev->constraints)
 432                 return sprintf(buf, "constraint not defined\n");
 433
 434         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 435 }
 436 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 437
 438 static ssize_t regulator_max_uA_show(struct device *dev,
 439                                     struct device_attribute *attr, char *buf)
 440 {
 441         struct regulator_dev *rdev = dev_get_drvdata(dev);
 442
 443         if (!rdev->constraints)
 444                 return sprintf(buf, "constraint not defined\n");
 445
 446         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 447 }
 448 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 449
 450 static ssize_t regulator_min_uV_show(struct device *dev,
 451                                     struct device_attribute *attr, char *buf)
 452 {
 453         struct regulator_dev *rdev = dev_get_drvdata(dev);
 454
 455         if (!rdev->constraints)
 456                 return sprintf(buf, "constraint not defined\n");
 457
 458         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 459 }
 460 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 461
 462 static ssize_t regulator_max_uV_show(struct device *dev,
 463                                     struct device_attribute *attr, char *buf)
 464 {
 465         struct regulator_dev *rdev = dev_get_drvdata(dev);
 466
 467         if (!rdev->constraints)
 468                 return sprintf(buf, "constraint not defined\n");
 469
 470         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 471 }
 472 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 473
 474 static ssize_t regulator_total_uA_show(struct device *dev,
 475                                       struct device_attribute *attr, char *buf)
 476 {
 477         struct regulator_dev *rdev = dev_get_drvdata(dev);
 478         struct regulator *regulator;
 479         int uA = 0;
 480
 481         mutex_lock(&rdev->mutex);
 482         list_for_each_entry(regulator, &rdev->consumer_list, list)
 483                 uA += regulator->uA_load;
 484         mutex_unlock(&rdev->mutex);
 485         return sprintf(buf, "%d\n", uA);
 486 }
 487 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 488
 489 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
 490                               char *buf)
 491 {
 492         struct regulator_dev *rdev = dev_get_drvdata(dev);
 493         return sprintf(buf, "%d\n", rdev->use_count);
 494 }
 495 static DEVICE_ATTR_RO(num_users);
 496
 497 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 498                          char *buf)
 499 {
 500         struct regulator_dev *rdev = dev_get_drvdata(dev);
 501
 502         switch (rdev->desc->type) {
 503         case REGULATOR_VOLTAGE:
 504                 return sprintf(buf, "voltage\n");
 505         case REGULATOR_CURRENT:
 506                 return sprintf(buf, "current\n");
 507         }
 508         return sprintf(buf, "unknown\n");
 509 }
 510 static DEVICE_ATTR_RO(type);
 511
 512 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 513                                 struct device_attribute *attr, char *buf)
 514 {
 515         struct regulator_dev *rdev = dev_get_drvdata(dev);
 516
 517         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 518 }
 519 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 520                 regulator_suspend_mem_uV_show, NULL);
 521
 522 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 523                                 struct device_attribute *attr, char *buf)
 524 {
 525         struct regulator_dev *rdev = dev_get_drvdata(dev);
 526
 527         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 528 }
 529 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 530                 regulator_suspend_disk_uV_show, NULL);
 531
 532 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 533                                 struct device_attribute *attr, char *buf)
 534 {
 535         struct regulator_dev *rdev = dev_get_drvdata(dev);
 536
 537         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 538 }
 539 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 540                 regulator_suspend_standby_uV_show, NULL);
 541
 542 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 543                                 struct device_attribute *attr, char *buf)
 544 {
 545         struct regulator_dev *rdev = dev_get_drvdata(dev);
 546
 547         return regulator_print_opmode(buf,
 548                 rdev->constraints->state_mem.mode);
 549 }
 550 static DEVICE_ATTR(suspend_mem_mode, 0444,
 551                 regulator_suspend_mem_mode_show, NULL);
 552
 553 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 554                                 struct device_attribute *attr, char *buf)
 555 {
 556         struct regulator_dev *rdev = dev_get_drvdata(dev);
 557
 558         return regulator_print_opmode(buf,
 559                 rdev->constraints->state_disk.mode);
 560 }
 561 static DEVICE_ATTR(suspend_disk_mode, 0444,
 562                 regulator_suspend_disk_mode_show, NULL);
 563
 564 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 565                                 struct device_attribute *attr, char *buf)
 566 {
 567         struct regulator_dev *rdev = dev_get_drvdata(dev);
 568
 569         return regulator_print_opmode(buf,
 570                 rdev->constraints->state_standby.mode);
 571 }
 572 static DEVICE_ATTR(suspend_standby_mode, 0444,
 573                 regulator_suspend_standby_mode_show, NULL);
 574
 575 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 576                                    struct device_attribute *attr, char *buf)
 577 {
 578         struct regulator_dev *rdev = dev_get_drvdata(dev);
 579
 580         return regulator_print_state(buf,
 581                         rdev->constraints->state_mem.enabled);
 582 }
 583 static DEVICE_ATTR(suspend_mem_state, 0444,
 584                 regulator_suspend_mem_state_show, NULL);
 585
 586 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 587                                    struct device_attribute *attr, char *buf)
 588 {
 589         struct regulator_dev *rdev = dev_get_drvdata(dev);
 590
 591         return regulator_print_state(buf,
 592                         rdev->constraints->state_disk.enabled);
 593 }
 594 static DEVICE_ATTR(suspend_disk_state, 0444,
 595                 regulator_suspend_disk_state_show, NULL);
 596
 597 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 598                                    struct device_attribute *attr, char *buf)
 599 {
 600         struct regulator_dev *rdev = dev_get_drvdata(dev);
 601
 602         return regulator_print_state(buf,
 603                         rdev->constraints->state_standby.enabled);
 604 }
 605 static DEVICE_ATTR(suspend_standby_state, 0444,
 606                 regulator_suspend_standby_state_show, NULL);
 607
 608 static ssize_t regulator_bypass_show(struct device *dev,
 609                                      struct device_attribute *attr, char *buf)
 610 {
 611         struct regulator_dev *rdev = dev_get_drvdata(dev);
 612         const char *report;
 613         bool bypass;
 614         int ret;
 615
 616         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
 617
 618         if (ret != 0)
 619                 report = "unknown";
 620         else if (bypass)
 621                 report = "enabled";
 622         else
 623                 report = "disabled";
 624
 625         return sprintf(buf, "%s\n", report);
 626 }
 627 static DEVICE_ATTR(bypass, 0444,
 628                    regulator_bypass_show, NULL);
 629
 630 /*
 631  * These are the only attributes are present for all regulators.
 632  * Other attributes are a function of regulator functionality.
 633  */
 634 static struct attribute *regulator_dev_attrs[] = {
 635         &dev_attr_name.attr,
 636         &dev_attr_num_users.attr,
 637         &dev_attr_type.attr,
 638         NULL,
 639 };
 640 ATTRIBUTE_GROUPS(regulator_dev);
 641
 642 static void regulator_dev_release(struct device *dev)
 643 {
 644         struct regulator_dev *rdev = dev_get_drvdata(dev);
 645         kfree(rdev);
 646 }
 647
 648 static struct class regulator_class = {
 649         .name = "regulator",
 650         .dev_release = regulator_dev_release,
 651         .dev_groups = regulator_dev_groups,
 652 };
 653
 654 /* Calculate the new optimum regulator operating mode based on the new total
 655  * consumer load. All locks held by caller */
 656 static void drms_uA_update(struct regulator_dev *rdev)
 657 {
 658         struct regulator *sibling;
 659         int current_uA = 0, output_uV, input_uV, err;
 660         unsigned int mode;
 661
 662         err = regulator_check_drms(rdev);
 663         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 664             (!rdev->desc->ops->get_voltage &&
 665              !rdev->desc->ops->get_voltage_sel) ||
 666             !rdev->desc->ops->set_mode)
 667                 return;
 668
 669         /* get output voltage */
 670         output_uV = _regulator_get_voltage(rdev);
 671         if (output_uV <= 0)
 672                 return;
 673
 674         /* get input voltage */
 675         input_uV = 0;
 676         if (rdev->supply)
 677                 input_uV = regulator_get_voltage(rdev->supply);
 678         if (input_uV <= 0)
 679                 input_uV = rdev->constraints->input_uV;
 680         if (input_uV <= 0)
 681                 return;
 682
 683         /* calc total requested load */
 684         list_for_each_entry(sibling, &rdev->consumer_list, list)
 685                 current_uA += sibling->uA_load;
 686
 687         /* now get the optimum mode for our new total regulator load */
 688         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 689                                                   output_uV, current_uA);
 690
 691         /* check the new mode is allowed */
 692         err = regulator_mode_constrain(rdev, &mode);
 693         if (err == 0)
 694                 rdev->desc->ops->set_mode(rdev, mode);
 695 }
 696
 697 static int suspend_set_state(struct regulator_dev *rdev,
 698         struct regulator_state *rstate)
 699 {
 700         int ret = 0;
 701
 702         /* If we have no suspend mode configration don't set anything;
 703          * only warn if the driver implements set_suspend_voltage or
 704          * set_suspend_mode callback.
 705          */
 706         if (!rstate->enabled && !rstate->disabled) {
 707                 if (rdev->desc->ops->set_suspend_voltage ||
 708                     rdev->desc->ops->set_suspend_mode)
 709                         rdev_warn(rdev, "No configuration\n");
 710                 return 0;
 711         }
 712
 713         if (rstate->enabled && rstate->disabled) {
 714                 rdev_err(rdev, "invalid configuration\n");
 715                 return -EINVAL;
 716         }
 717
 718         if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
 719                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 720         else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
 721                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 722         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
 723                 ret = 0;
 724
 725         if (ret < 0) {
 726                 rdev_err(rdev, "failed to enabled/disable\n");
 727                 return ret;
 728         }
 729
 730         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 731                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 732                 if (ret < 0) {
 733                         rdev_err(rdev, "failed to set voltage\n");
 734                         return ret;
 735                 }
 736         }
 737
 738         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 739                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 740                 if (ret < 0) {
 741                         rdev_err(rdev, "failed to set mode\n");
 742                         return ret;
 743                 }
 744         }
 745         return ret;
 746 }
 747
 748 /* locks held by caller */
 749 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 750 {
 751         if (!rdev->constraints)
 752                 return -EINVAL;
 753
 754         switch (state) {
 755         case PM_SUSPEND_STANDBY:
 756                 return suspend_set_state(rdev,
 757                         &rdev->constraints->state_standby);
 758         case PM_SUSPEND_MEM:
 759                 return suspend_set_state(rdev,
 760                         &rdev->constraints->state_mem);
 761         case PM_SUSPEND_MAX:
 762                 return suspend_set_state(rdev,
 763                         &rdev->constraints->state_disk);
 764         default:
 765                 return -EINVAL;
 766         }
 767 }
 768
 769 static void print_constraints(struct regulator_dev *rdev)
 770 {
 771         struct regulation_constraints *constraints = rdev->constraints;
 772         char buf[80] = "";
 773         int count = 0;
 774         int ret;
 775
 776         if (constraints->min_uV && constraints->max_uV) {
 777                 if (constraints->min_uV == constraints->max_uV)
 778                         count += sprintf(buf + count, "%d mV ",
 779                                          constraints->min_uV / 1000);
 780                 else
 781                         count += sprintf(buf + count, "%d <--> %d mV ",
 782                                          constraints->min_uV / 1000,
 783                                          constraints->max_uV / 1000);
 784         }
 785
 786         if (!constraints->min_uV ||
 787             constraints->min_uV != constraints->max_uV) {
 788                 ret = _regulator_get_voltage(rdev);
 789                 if (ret > 0)
 790                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 791         }
 792
 793         if (constraints->uV_offset)
 794                 count += sprintf(buf, "%dmV offset ",
 795                                  constraints->uV_offset / 1000);
 796
 797         if (constraints->min_uA && constraints->max_uA) {
 798                 if (constraints->min_uA == constraints->max_uA)
 799                         count += sprintf(buf + count, "%d mA ",
 800                                          constraints->min_uA / 1000);
 801                 else
 802                         count += sprintf(buf + count, "%d <--> %d mA ",
 803                                          constraints->min_uA / 1000,
 804                                          constraints->max_uA / 1000);
 805         }
 806
 807         if (!constraints->min_uA ||
 808             constraints->min_uA != constraints->max_uA) {
 809                 ret = _regulator_get_current_limit(rdev);
 810                 if (ret > 0)
 811                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
 812         }
 813
 814         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 815                 count += sprintf(buf + count, "fast ");
 816         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 817                 count += sprintf(buf + count, "normal ");
 818         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 819                 count += sprintf(buf + count, "idle ");
 820         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 821                 count += sprintf(buf + count, "standby");
 822
 823         if (!count)
 824                 sprintf(buf, "no parameters");
 825
 826         rdev_info(rdev, "%s\n", buf);
 827
 828         if ((constraints->min_uV != constraints->max_uV) &&
 829             !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
 830                 rdev_warn(rdev,
 831                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
 832 }
 833
 834 static int machine_constraints_voltage(struct regulator_dev *rdev,
 835         struct regulation_constraints *constraints)
 836 {
 837         struct regulator_ops *ops = rdev->desc->ops;
 838         int ret;
 839
 840         /* do we need to apply the constraint voltage */
 841         if (rdev->constraints->apply_uV &&
 842             rdev->constraints->min_uV == rdev->constraints->max_uV) {
 843                 ret = _regulator_do_set_voltage(rdev,
 844                                                 rdev->constraints->min_uV,
 845                                                 rdev->constraints->max_uV);
 846                 if (ret < 0) {
 847                         rdev_err(rdev, "failed to apply %duV constraint\n",
 848                                  rdev->constraints->min_uV);
 849                         return ret;
 850                 }
 851         }
 852
 853         /* constrain machine-level voltage specs to fit
 854          * the actual range supported by this regulator.
 855          */
 856         if (ops->list_voltage && rdev->desc->n_voltages) {
 857                 int     count = rdev->desc->n_voltages;
 858                 int     i;
 859                 int     min_uV = INT_MAX;
 860                 int     max_uV = INT_MIN;
 861                 int     cmin = constraints->min_uV;
 862                 int     cmax = constraints->max_uV;
 863
 864                 /* it's safe to autoconfigure fixed-voltage supplies
 865                    and the constraints are used by list_voltage. */
 866                 if (count == 1 && !cmin) {
 867                         cmin = 1;
 868                         cmax = INT_MAX;
 869                         constraints->min_uV = cmin;
 870                         constraints->max_uV = cmax;
 871                 }
 872
 873                 /* voltage constraints are optional */
 874                 if ((cmin == 0) && (cmax == 0))
 875                         return 0;
 876
 877                 /* else require explicit machine-level constraints */
 878                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 879                         rdev_err(rdev, "invalid voltage constraints\n");
 880                         return -EINVAL;
 881                 }
 882
 883                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 884                 for (i = 0; i < count; i++) {
 885                         int     value;
 886
 887                         value = ops->list_voltage(rdev, i);
 888                         if (value <= 0)
 889                                 continue;
 890
 891                         /* maybe adjust [min_uV..max_uV] */
 892                         if (value >= cmin && value < min_uV)
 893                                 min_uV = value;
 894                         if (value <= cmax && value > max_uV)
 895                                 max_uV = value;
 896                 }
 897
 898                 /* final: [min_uV..max_uV] valid iff constraints valid */
 899                 if (max_uV < min_uV) {
 900                         rdev_err(rdev,
 901                                  "unsupportable voltage constraints %u-%uuV\n",
 902                                  min_uV, max_uV);
 903                         return -EINVAL;
 904                 }
 905
 906                 /* use regulator's subset of machine constraints */
 907                 if (constraints->min_uV < min_uV) {
 908                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
 909                                  constraints->min_uV, min_uV);
 910                         constraints->min_uV = min_uV;
 911                 }
 912                 if (constraints->max_uV > max_uV) {
 913                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
 914                                  constraints->max_uV, max_uV);
 915                         constraints->max_uV = max_uV;
 916                 }
 917         }
 918
 919         return 0;
 920 }
 921
 922 /**
 923  * set_machine_constraints - sets regulator constraints
 924  * @rdev: regulator source
 925  * @constraints: constraints to apply
 926  *
 927  * Allows platform initialisation code to define and constrain
 928  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 929  * Constraints *must* be set by platform code in order for some
 930  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 931  * set_mode.
 932  */
 933 static int set_machine_constraints(struct regulator_dev *rdev,
 934         const struct regulation_constraints *constraints)
 935 {
 936         int ret = 0;
 937         struct regulator_ops *ops = rdev->desc->ops;
 938
 939         if (constraints)
 940                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
 941                                             GFP_KERNEL);
 942         else
 943                 rdev->constraints = kzalloc(sizeof(*constraints),
 944                                             GFP_KERNEL);
 945         if (!rdev->constraints)
 946                 return -ENOMEM;
 947
 948         ret = machine_constraints_voltage(rdev, rdev->constraints);
 949         if (ret != 0)
 950                 goto out;
 951
 952         /* do we need to setup our suspend state */
 953         if (rdev->constraints->initial_state) {
 954                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
 955                 if (ret < 0) {
 956                         rdev_err(rdev, "failed to set suspend state\n");
 957                         goto out;
 958                 }
 959         }
 960
 961         if (rdev->constraints->initial_mode) {
 962                 if (!ops->set_mode) {
 963                         rdev_err(rdev, "no set_mode operation\n");
 964                         ret = -EINVAL;
 965                         goto out;
 966                 }
 967
 968                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
 969                 if (ret < 0) {
 970                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
 971                         goto out;
 972                 }
 973         }
 974
 975         /* If the constraints say the regulator should be on at this point
 976          * and we have control then make sure it is enabled.
 977          */
 978         if ((rdev->constraints->always_on || rdev->constraints->boot_on) &&
 979             ops->enable) {
 980                 ret = ops->enable(rdev);
 981                 if (ret < 0) {
 982                         rdev_err(rdev, "failed to enable\n");
 983                         goto out;
 984                 }
 985         }
 986
 987         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
 988                 && ops->set_ramp_delay) {
 989                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
 990                 if (ret < 0) {
 991                         rdev_err(rdev, "failed to set ramp_delay\n");
 992                         goto out;
 993                 }
 994         }
 995
 996         print_constraints(rdev);
 997         return 0;
 998 out:
 999         kfree(rdev->constraints);
1000         rdev->constraints = NULL;
1001         return ret;
1002 }
1003
1004 /**
1005  * set_supply - set regulator supply regulator
1006  * @rdev: regulator name
1007  * @supply_rdev: supply regulator name
1008  *
1009  * Called by platform initialisation code to set the supply regulator for this
1010  * regulator. This ensures that a regulators supply will also be enabled by the
1011  * core if it's child is enabled.
1012  */
1013 static int set_supply(struct regulator_dev *rdev,
1014                       struct regulator_dev *supply_rdev)
1015 {
1016         int err;
1017
1018         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1019
1020         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1021         if (rdev->supply == NULL) {
1022                 err = -ENOMEM;
1023                 return err;
1024         }
1025         supply_rdev->open_count++;
1026
1027         return 0;
1028 }
1029
1030 /**
1031  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1032  * @rdev:         regulator source
1033  * @consumer_dev_name: dev_name() string for device supply applies to
1034  * @supply:       symbolic name for supply
1035  *
1036  * Allows platform initialisation code to map physical regulator
1037  * sources to symbolic names for supplies for use by devices.  Devices
1038  * should use these symbolic names to request regulators, avoiding the
1039  * need to provide board-specific regulator names as platform data.
1040  */
1041 static int set_consumer_device_supply(struct regulator_dev *rdev,
1042                                       const char *consumer_dev_name,
1043                                       const char *supply)
1044 {
1045         struct regulator_map *node;
1046         int has_dev;
1047
1048         if (supply == NULL)
1049                 return -EINVAL;
1050
1051         if (consumer_dev_name != NULL)
1052                 has_dev = 1;
1053         else
1054                 has_dev = 0;
1055
1056         list_for_each_entry(node, &regulator_map_list, list) {
1057                 if (node->dev_name && consumer_dev_name) {
1058                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1059                                 continue;
1060                 } else if (node->dev_name || consumer_dev_name) {
1061                         continue;
1062                 }
1063
1064                 if (strcmp(node->supply, supply) != 0)
1065                         continue;
1066
1067                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1068                          consumer_dev_name,
1069                          dev_name(&node->regulator->dev),
1070                          node->regulator->desc->name,
1071                          supply,
1072                          dev_name(&rdev->dev), rdev_get_name(rdev));
1073                 return -EBUSY;
1074         }
1075
1076         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1077         if (node == NULL)
1078                 return -ENOMEM;
1079
1080         node->regulator = rdev;
1081         node->supply = supply;
1082
1083         if (has_dev) {
1084                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1085                 if (node->dev_name == NULL) {
1086                         kfree(node);
1087                         return -ENOMEM;
1088                 }
1089         }
1090
1091         list_add(&node->list, &regulator_map_list);
1092         return 0;
1093 }
1094
1095 static void unset_regulator_supplies(struct regulator_dev *rdev)
1096 {
1097         struct regulator_map *node, *n;
1098
1099         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1100                 if (rdev == node->regulator) {
1101                         list_del(&node->list);
1102                         kfree(node->dev_name);
1103                         kfree(node);
1104                 }
1105         }
1106 }
1107
1108 #define REG_STR_SIZE    64
1109
1110 static struct regulator *create_regulator(struct regulator_dev *rdev,
1111                                           struct device *dev,
1112                                           const char *supply_name)
1113 {
1114         struct regulator *regulator;
1115         char buf[REG_STR_SIZE];
1116         int err, size;
1117
1118         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1119         if (regulator == NULL)
1120                 return NULL;
1121
1122         mutex_lock(&rdev->mutex);
1123         regulator->rdev = rdev;
1124         list_add(&regulator->list, &rdev->consumer_list);
1125
1126         if (dev) {
1127                 regulator->dev = dev;
1128
1129                 /* Add a link to the device sysfs entry */
1130                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1131                                  dev->kobj.name, supply_name);
1132                 if (size >= REG_STR_SIZE)
1133                         goto overflow_err;
1134
1135                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1136                 if (regulator->supply_name == NULL)
1137                         goto overflow_err;
1138
1139                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1140                                         buf);
1141                 if (err) {
1142                         rdev_warn(rdev, "could not add device link %s err %d\n",
1143                                   dev->kobj.name, err);
1144                         /* non-fatal */
1145                 }
1146         } else {
1147                 regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1148                 if (regulator->supply_name == NULL)
1149                         goto overflow_err;
1150         }
1151
1152         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1153                                                 rdev->debugfs);
1154         if (!regulator->debugfs) {
1155                 rdev_warn(rdev, "Failed to create debugfs directory\n");
1156         } else {
1157                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1158                                    &regulator->uA_load);
1159                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1160                                    &regulator->min_uV);
1161                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1162                                    &regulator->max_uV);
1163         }
1164
1165         /*
1166          * Check now if the regulator is an always on regulator - if
1167          * it is then we don't need to do nearly so much work for
1168          * enable/disable calls.
1169          */
1170         if (!_regulator_can_change_status(rdev) &&
1171             _regulator_is_enabled(rdev))
1172                 regulator->always_on = true;
1173
1174         mutex_unlock(&rdev->mutex);
1175         return regulator;
1176 overflow_err:
1177         list_del(&regulator->list);
1178         kfree(regulator);
1179         mutex_unlock(&rdev->mutex);
1180         return NULL;
1181 }
1182
1183 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1184 {
1185         if (!rdev->desc->ops->enable_time)
1186                 return rdev->desc->enable_time;
1187         return rdev->desc->ops->enable_time(rdev);
1188 }
1189
1190 static struct regulator_supply_alias *regulator_find_supply_alias(
1191                 struct device *dev, const char *supply)
1192 {
1193         struct regulator_supply_alias *map;
1194
1195         list_for_each_entry(map, &regulator_supply_alias_list, list)
1196                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1197                         return map;
1198
1199         return NULL;
1200 }
1201
1202 static void regulator_supply_alias(struct device **dev, const char **supply)
1203 {
1204         struct regulator_supply_alias *map;
1205
1206         map = regulator_find_supply_alias(*dev, *supply);
1207         if (map) {
1208                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1209                                 *supply, map->alias_supply,
1210                                 dev_name(map->alias_dev));
1211                 *dev = map->alias_dev;
1212                 *supply = map->alias_supply;
1213         }
1214 }
1215
1216 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1217                                                   const char *supply,
1218                                                   int *ret)
1219 {
1220         struct regulator_dev *r;
1221         struct device_node *node;
1222         struct regulator_map *map;
1223         const char *devname = NULL;
1224
1225         regulator_supply_alias(&dev, &supply);
1226
1227         /* first do a dt based lookup */
1228         if (dev && dev->of_node) {
1229                 node = of_get_regulator(dev, supply);
1230                 if (node) {
1231                         list_for_each_entry(r, &regulator_list, list)
1232                                 if (r->dev.parent &&
1233                                         node == r->dev.of_node)
1234                                         return r;
1235                 } else {
1236                         /*
1237                          * If we couldn't even get the node then it's
1238                          * not just that the device didn't register
1239                          * yet, there's no node and we'll never
1240                          * succeed.
1241                          */
1242                         *ret = -ENODEV;
1243                 }
1244         }
1245
1246         /* if not found, try doing it non-dt way */
1247         if (dev)
1248                 devname = dev_name(dev);
1249
1250         list_for_each_entry(r, &regulator_list, list)
1251                 if (strcmp(rdev_get_name(r), supply) == 0)
1252                         return r;
1253
1254         list_for_each_entry(map, &regulator_map_list, list) {
1255                 /* If the mapping has a device set up it must match */
1256                 if (map->dev_name &&
1257                     (!devname || strcmp(map->dev_name, devname)))
1258                         continue;
1259
1260                 if (strcmp(map->supply, supply) == 0)
1261                         return map->regulator;
1262         }
1263
1264
1265         return NULL;
1266 }
1267
1268 /* Internal regulator request function */
1269 static struct regulator *_regulator_get(struct device *dev, const char *id,
1270                                         bool exclusive)
1271 {
1272         struct regulator_dev *rdev;
1273         struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1274         const char *devname = NULL;
1275         int ret = 0;
1276
1277         if (id == NULL) {
1278                 pr_err("get() with no identifier\n");
1279                 return regulator;
1280         }
1281
1282         if (dev)
1283                 devname = dev_name(dev);
1284
1285         mutex_lock(&regulator_list_mutex);
1286
1287         rdev = regulator_dev_lookup(dev, id, &ret);
1288         if (rdev)
1289                 goto found;
1290
1291         /*
1292          * If we have return value from dev_lookup fail, we do not expect to
1293          * succeed, so, quit with appropriate error value
1294          */
1295         if (ret) {
1296                 regulator = ERR_PTR(ret);
1297                 goto out;
1298         }
1299
1300         if (board_wants_dummy_regulator) {
1301                 rdev = dummy_regulator_rdev;
1302                 goto found;
1303         }
1304
1305 #ifdef CONFIG_REGULATOR_DUMMY
1306         if (!devname)
1307                 devname = "deviceless";
1308
1309         /* If the board didn't flag that it was fully constrained then
1310          * substitute in a dummy regulator so consumers can continue.
1311          */
1312         if (!has_full_constraints) {
1313                 pr_warn("%s supply %s not found, using dummy regulator\n",
1314                         devname, id);
1315                 rdev = dummy_regulator_rdev;
1316                 goto found;
1317         }
1318 #endif
1319
1320         mutex_unlock(&regulator_list_mutex);
1321         return regulator;
1322
1323 found:
1324         if (rdev->exclusive) {
1325                 regulator = ERR_PTR(-EPERM);
1326                 goto out;
1327         }
1328
1329         if (exclusive && rdev->open_count) {
1330                 regulator = ERR_PTR(-EBUSY);
1331                 goto out;
1332         }
1333
1334         if (!try_module_get(rdev->owner))
1335                 goto out;
1336
1337         regulator = create_regulator(rdev, dev, id);
1338         if (regulator == NULL) {
1339                 regulator = ERR_PTR(-ENOMEM);
1340                 module_put(rdev->owner);
1341                 goto out;
1342         }
1343
1344         rdev->open_count++;
1345         if (exclusive) {
1346                 rdev->exclusive = 1;
1347
1348                 ret = _regulator_is_enabled(rdev);
1349                 if (ret > 0)
1350                         rdev->use_count = 1;
1351                 else
1352                         rdev->use_count = 0;
1353         }
1354
1355 out:
1356         mutex_unlock(&regulator_list_mutex);
1357
1358         return regulator;
1359 }
1360
1361 /**
1362  * regulator_get - lookup and obtain a reference to a regulator.
1363  * @dev: device for regulator "consumer"
1364  * @id: Supply name or regulator ID.
1365  *
1366  * Returns a struct regulator corresponding to the regulator producer,
1367  * or IS_ERR() condition containing errno.
1368  *
1369  * Use of supply names configured via regulator_set_device_supply() is
1370  * strongly encouraged.  It is recommended that the supply name used
1371  * should match the name used for the supply and/or the relevant
1372  * device pins in the datasheet.
1373  */
1374 struct regulator *regulator_get(struct device *dev, const char *id)
1375 {
1376         return _regulator_get(dev, id, false);
1377 }
1378 EXPORT_SYMBOL_GPL(regulator_get);
1379
1380 /**
1381  * regulator_get_exclusive - obtain exclusive access to a regulator.
1382  * @dev: device for regulator "consumer"
1383  * @id: Supply name or regulator ID.
1384  *
1385  * Returns a struct regulator corresponding to the regulator producer,
1386  * or IS_ERR() condition containing errno.  Other consumers will be
1387  * unable to obtain this reference is held and the use count for the
1388  * regulator will be initialised to reflect the current state of the
1389  * regulator.
1390  *
1391  * This is intended for use by consumers which cannot tolerate shared
1392  * use of the regulator such as those which need to force the
1393  * regulator off for correct operation of the hardware they are
1394  * controlling.
1395  *
1396  * Use of supply names configured via regulator_set_device_supply() is
1397  * strongly encouraged.  It is recommended that the supply name used
1398  * should match the name used for the supply and/or the relevant
1399  * device pins in the datasheet.
1400  */
1401 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1402 {
1403         return _regulator_get(dev, id, true);
1404 }
1405 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1406
1407 /**
1408  * regulator_get_optional - obtain optional access to a regulator.
1409  * @dev: device for regulator "consumer"
1410  * @id: Supply name or regulator ID.
1411  *
1412  * Returns a struct regulator corresponding to the regulator producer,
1413  * or IS_ERR() condition containing errno.  Other consumers will be
1414  * unable to obtain this reference is held and the use count for the
1415  * regulator will be initialised to reflect the current state of the
1416  * regulator.
1417  *
1418  * This is intended for use by consumers for devices which can have
1419  * some supplies unconnected in normal use, such as some MMC devices.
1420  * It can allow the regulator core to provide stub supplies for other
1421  * supplies requested using normal regulator_get() calls without
1422  * disrupting the operation of drivers that can handle absent
1423  * supplies.
1424  *
1425  * Use of supply names configured via regulator_set_device_supply() is
1426  * strongly encouraged.  It is recommended that the supply name used
1427  * should match the name used for the supply and/or the relevant
1428  * device pins in the datasheet.
1429  */
1430 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1431 {
1432         return _regulator_get(dev, id, 0);
1433 }
1434 EXPORT_SYMBOL_GPL(regulator_get_optional);
1435
1436 /* Locks held by regulator_put() */
1437 static void _regulator_put(struct regulator *regulator)
1438 {
1439         struct regulator_dev *rdev;
1440
1441         if (regulator == NULL || IS_ERR(regulator))
1442                 return;
1443
1444         rdev = regulator->rdev;
1445
1446         debugfs_remove_recursive(regulator->debugfs);
1447
1448         /* remove any sysfs entries */
1449         if (regulator->dev)
1450                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1451         kfree(regulator->supply_name);
1452         list_del(&regulator->list);
1453         kfree(regulator);
1454
1455         rdev->open_count--;
1456         rdev->exclusive = 0;
1457
1458         module_put(rdev->owner);
1459 }
1460
1461 /**
1462  * regulator_put - "free" the regulator source
1463  * @regulator: regulator source
1464  *
1465  * Note: drivers must ensure that all regulator_enable calls made on this
1466  * regulator source are balanced by regulator_disable calls prior to calling
1467  * this function.
1468  */
1469 void regulator_put(struct regulator *regulator)
1470 {
1471         mutex_lock(&regulator_list_mutex);
1472         _regulator_put(regulator);
1473         mutex_unlock(&regulator_list_mutex);
1474 }
1475 EXPORT_SYMBOL_GPL(regulator_put);
1476
1477 /**
1478  * regulator_register_supply_alias - Provide device alias for supply lookup
1479  *
1480  * @dev: device that will be given as the regulator "consumer"
1481  * @id: Supply name or regulator ID
1482  * @alias_dev: device that should be used to lookup the supply
1483  * @alias_id: Supply name or regulator ID that should be used to lookup the
1484  * supply
1485  *
1486  * All lookups for id on dev will instead be conducted for alias_id on
1487  * alias_dev.
1488  */
1489 int regulator_register_supply_alias(struct device *dev, const char *id,
1490                                     struct device *alias_dev,
1491                                     const char *alias_id)
1492 {
1493         struct regulator_supply_alias *map;
1494
1495         map = regulator_find_supply_alias(dev, id);
1496         if (map)
1497                 return -EEXIST;
1498
1499         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1500         if (!map)
1501                 return -ENOMEM;
1502
1503         map->src_dev = dev;
1504         map->src_supply = id;
1505         map->alias_dev = alias_dev;
1506         map->alias_supply = alias_id;
1507
1508         list_add(&map->list, &regulator_supply_alias_list);
1509
1510         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1511                 id, dev_name(dev), alias_id, dev_name(alias_dev));
1512
1513         return 0;
1514 }
1515 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1516
1517 /**
1518  * regulator_unregister_supply_alias - Remove device alias
1519  *
1520  * @dev: device that will be given as the regulator "consumer"
1521  * @id: Supply name or regulator ID
1522  *
1523  * Remove a lookup alias if one exists for id on dev.
1524  */
1525 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1526 {
1527         struct regulator_supply_alias *map;
1528
1529         map = regulator_find_supply_alias(dev, id);
1530         if (map) {
1531                 list_del(&map->list);
1532                 kfree(map);
1533         }
1534 }
1535 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1536
1537 /**
1538  * regulator_bulk_register_supply_alias - register multiple aliases
1539  *
1540  * @dev: device that will be given as the regulator "consumer"
1541  * @id: List of supply names or regulator IDs
1542  * @alias_dev: device that should be used to lookup the supply
1543  * @alias_id: List of supply names or regulator IDs that should be used to
1544  * lookup the supply
1545  * @num_id: Number of aliases to register
1546  *
1547  * @return 0 on success, an errno on failure.
1548  *
1549  * This helper function allows drivers to register several supply
1550  * aliases in one operation.  If any of the aliases cannot be
1551  * registered any aliases that were registered will be removed
1552  * before returning to the caller.
1553  */
1554 int regulator_bulk_register_supply_alias(struct device *dev, const char **id,
1555                                          struct device *alias_dev,
1556                                          const char **alias_id,
1557                                          int num_id)
1558 {
1559         int i;
1560         int ret;
1561
1562         for (i = 0; i < num_id; ++i) {
1563                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1564                                                       alias_id[i]);
1565                 if (ret < 0)
1566                         goto err;
1567         }
1568
1569         return 0;
1570
1571 err:
1572         dev_err(dev,
1573                 "Failed to create supply alias %s,%s -> %s,%s\n",
1574                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1575
1576         while (--i >= 0)
1577                 regulator_unregister_supply_alias(dev, id[i]);
1578
1579         return ret;
1580 }
1581 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1582
1583 /**
1584  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1585  *
1586  * @dev: device that will be given as the regulator "consumer"
1587  * @id: List of supply names or regulator IDs
1588  * @num_id: Number of aliases to unregister
1589  *
1590  * This helper function allows drivers to unregister several supply
1591  * aliases in one operation.
1592  */
1593 void regulator_bulk_unregister_supply_alias(struct device *dev,
1594                                             const char **id,
1595                                             int num_id)
1596 {
1597         int i;
1598
1599         for (i = 0; i < num_id; ++i)
1600                 regulator_unregister_supply_alias(dev, id[i]);
1601 }
1602 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1603
1604
1605 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1606 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1607                                 const struct regulator_config *config)
1608 {
1609         struct regulator_enable_gpio *pin;
1610         int ret;
1611
1612         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1613                 if (pin->gpio == config->ena_gpio) {
1614                         rdev_dbg(rdev, "GPIO %d is already used\n",
1615                                 config->ena_gpio);
1616                         goto update_ena_gpio_to_rdev;
1617                 }
1618         }
1619
1620         ret = gpio_request_one(config->ena_gpio,
1621                                 GPIOF_DIR_OUT | config->ena_gpio_flags,
1622                                 rdev_get_name(rdev));
1623         if (ret)
1624                 return ret;
1625
1626         pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1627         if (pin == NULL) {
1628                 gpio_free(config->ena_gpio);
1629                 return -ENOMEM;
1630         }
1631
1632         pin->gpio = config->ena_gpio;
1633         pin->ena_gpio_invert = config->ena_gpio_invert;
1634         list_add(&pin->list, &regulator_ena_gpio_list);
1635
1636 update_ena_gpio_to_rdev:
1637         pin->request_count++;
1638         rdev->ena_pin = pin;
1639         return 0;
1640 }
1641
1642 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1643 {
1644         struct regulator_enable_gpio *pin, *n;
1645
1646         if (!rdev->ena_pin)
1647                 return;
1648
1649         /* Free the GPIO only in case of no use */
1650         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1651                 if (pin->gpio == rdev->ena_pin->gpio) {
1652                         if (pin->request_count <= 1) {
1653                                 pin->request_count = 0;
1654                                 gpio_free(pin->gpio);
1655                                 list_del(&pin->list);
1656                                 kfree(pin);
1657                         } else {
1658                                 pin->request_count--;
1659                         }
1660                 }
1661         }
1662 }
1663
1664 /**
1665  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1666  * @rdev: regulator_dev structure
1667  * @enable: enable GPIO at initial use?
1668  *
1669  * GPIO is enabled in case of initial use. (enable_count is 0)
1670  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1671  */
1672 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1673 {
1674         struct regulator_enable_gpio *pin = rdev->ena_pin;
1675
1676         if (!pin)
1677                 return -EINVAL;
1678
1679         if (enable) {
1680                 /* Enable GPIO at initial use */
1681                 if (pin->enable_count == 0)
1682                         gpio_set_value_cansleep(pin->gpio,
1683                                                 !pin->ena_gpio_invert);
1684
1685                 pin->enable_count++;
1686         } else {
1687                 if (pin->enable_count > 1) {
1688                         pin->enable_count--;
1689                         return 0;
1690                 }
1691
1692                 /* Disable GPIO if not used */
1693                 if (pin->enable_count <= 1) {
1694                         gpio_set_value_cansleep(pin->gpio,
1695                                                 pin->ena_gpio_invert);
1696                         pin->enable_count = 0;
1697                 }
1698         }
1699
1700         return 0;
1701 }
1702
1703 static int _regulator_do_enable(struct regulator_dev *rdev)
1704 {
1705         int ret, delay;
1706
1707         /* Query before enabling in case configuration dependent.  */
1708         ret = _regulator_get_enable_time(rdev);
1709         if (ret >= 0) {
1710                 delay = ret;
1711         } else {
1712                 rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1713                 delay = 0;
1714         }
1715
1716         trace_regulator_enable(rdev_get_name(rdev));
1717
1718         if (rdev->ena_pin) {
1719                 ret = regulator_ena_gpio_ctrl(rdev, true);
1720                 if (ret < 0)
1721                         return ret;
1722                 rdev->ena_gpio_state = 1;
1723         } else if (rdev->desc->ops->enable) {
1724                 ret = rdev->desc->ops->enable(rdev);
1725                 if (ret < 0)
1726                         return ret;
1727         } else {
1728                 return -EINVAL;
1729         }
1730
1731         /* Allow the regulator to ramp; it would be useful to extend
1732          * this for bulk operations so that the regulators can ramp
1733          * together.  */
1734         trace_regulator_enable_delay(rdev_get_name(rdev));
1735
1736         if (delay >= 1000) {
1737                 mdelay(delay / 1000);
1738                 udelay(delay % 1000);
1739         } else if (delay) {
1740                 udelay(delay);
1741         }
1742
1743         trace_regulator_enable_complete(rdev_get_name(rdev));
1744
1745         return 0;
1746 }
1747
1748 /* locks held by regulator_enable() */
1749 static int _regulator_enable(struct regulator_dev *rdev)
1750 {
1751         int ret;
1752
1753         /* check voltage and requested load before enabling */
1754         if (rdev->constraints &&
1755             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1756                 drms_uA_update(rdev);
1757
1758         if (rdev->use_count == 0) {
1759                 /* The regulator may on if it's not switchable or left on */
1760                 ret = _regulator_is_enabled(rdev);
1761                 if (ret == -EINVAL || ret == 0) {
1762                         if (!_regulator_can_change_status(rdev))
1763                                 return -EPERM;
1764
1765                         ret = _regulator_do_enable(rdev);
1766                         if (ret < 0)
1767                                 return ret;
1768
1769                 } else if (ret < 0) {
1770                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1771                         return ret;
1772                 }
1773                 /* Fallthrough on positive return values - already enabled */
1774         }
1775
1776         rdev->use_count++;
1777
1778         return 0;
1779 }
1780
1781 /**
1782  * regulator_enable - enable regulator output
1783  * @regulator: regulator source
1784  *
1785  * Request that the regulator be enabled with the regulator output at
1786  * the predefined voltage or current value.  Calls to regulator_enable()
1787  * must be balanced with calls to regulator_disable().
1788  *
1789  * NOTE: the output value can be set by other drivers, boot loader or may be
1790  * hardwired in the regulator.
1791  */
1792 int regulator_enable(struct regulator *regulator)
1793 {
1794         struct regulator_dev *rdev = regulator->rdev;
1795         int ret = 0;
1796
1797         if (regulator->always_on)
1798                 return 0;
1799
1800         if (rdev->supply) {
1801                 ret = regulator_enable(rdev->supply);
1802                 if (ret != 0)
1803                         return ret;
1804         }
1805
1806         mutex_lock(&rdev->mutex);
1807         ret = _regulator_enable(rdev);
1808         mutex_unlock(&rdev->mutex);
1809
1810         if (ret != 0 && rdev->supply)
1811                 regulator_disable(rdev->supply);
1812
1813         return ret;
1814 }
1815 EXPORT_SYMBOL_GPL(regulator_enable);
1816
1817 static int _regulator_do_disable(struct regulator_dev *rdev)
1818 {
1819         int ret;
1820
1821         trace_regulator_disable(rdev_get_name(rdev));
1822
1823         if (rdev->ena_pin) {
1824                 ret = regulator_ena_gpio_ctrl(rdev, false);
1825                 if (ret < 0)
1826                         return ret;
1827                 rdev->ena_gpio_state = 0;
1828
1829         } else if (rdev->desc->ops->disable) {
1830                 ret = rdev->desc->ops->disable(rdev);
1831                 if (ret != 0)
1832                         return ret;
1833         }
1834
1835         trace_regulator_disable_complete(rdev_get_name(rdev));
1836
1837         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1838                              NULL);
1839         return 0;
1840 }
1841
1842 /* locks held by regulator_disable() */
1843 static int _regulator_disable(struct regulator_dev *rdev)
1844 {
1845         int ret = 0;
1846
1847         if (WARN(rdev->use_count <= 0,
1848                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
1849                 return -EIO;
1850
1851         /* are we the last user and permitted to disable ? */
1852         if (rdev->use_count == 1 &&
1853             (rdev->constraints && !rdev->constraints->always_on)) {
1854
1855                 /* we are last user */
1856                 if (_regulator_can_change_status(rdev)) {
1857                         ret = _regulator_do_disable(rdev);
1858                         if (ret < 0) {
1859                                 rdev_err(rdev, "failed to disable\n");
1860                                 return ret;
1861                         }
1862                 }
1863
1864                 rdev->use_count = 0;
1865         } else if (rdev->use_count > 1) {
1866
1867                 if (rdev->constraints &&
1868                         (rdev->constraints->valid_ops_mask &
1869                         REGULATOR_CHANGE_DRMS))
1870                         drms_uA_update(rdev);
1871
1872                 rdev->use_count--;
1873         }
1874
1875         return ret;
1876 }
1877
1878 /**
1879  * regulator_disable - disable regulator output
1880  * @regulator: regulator source
1881  *
1882  * Disable the regulator output voltage or current.  Calls to
1883  * regulator_enable() must be balanced with calls to
1884  * regulator_disable().
1885  *
1886  * NOTE: this will only disable the regulator output if no other consumer
1887  * devices have it enabled, the regulator device supports disabling and
1888  * machine constraints permit this operation.
1889  */
1890 int regulator_disable(struct regulator *regulator)
1891 {
1892         struct regulator_dev *rdev = regulator->rdev;
1893         int ret = 0;
1894
1895         if (regulator->always_on)
1896                 return 0;
1897
1898         mutex_lock(&rdev->mutex);
1899         ret = _regulator_disable(rdev);
1900         mutex_unlock(&rdev->mutex);
1901
1902         if (ret == 0 && rdev->supply)
1903                 regulator_disable(rdev->supply);
1904
1905         return ret;
1906 }
1907 EXPORT_SYMBOL_GPL(regulator_disable);
1908
1909 /* locks held by regulator_force_disable() */
1910 static int _regulator_force_disable(struct regulator_dev *rdev)
1911 {
1912         int ret = 0;
1913
1914         /* force disable */
1915         if (rdev->desc->ops->disable) {
1916                 /* ah well, who wants to live forever... */
1917                 ret = rdev->desc->ops->disable(rdev);
1918                 if (ret < 0) {
1919                         rdev_err(rdev, "failed to force disable\n");
1920                         return ret;
1921                 }
1922                 /* notify other consumers that power has been forced off */
1923                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1924                         REGULATOR_EVENT_DISABLE, NULL);
1925         }
1926
1927         return ret;
1928 }
1929
1930 /**
1931  * regulator_force_disable - force disable regulator output
1932  * @regulator: regulator source
1933  *
1934  * Forcibly disable the regulator output voltage or current.
1935  * NOTE: this *will* disable the regulator output even if other consumer
1936  * devices have it enabled. This should be used for situations when device
1937  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1938  */
1939 int regulator_force_disable(struct regulator *regulator)
1940 {
1941         struct regulator_dev *rdev = regulator->rdev;
1942         int ret;
1943
1944         mutex_lock(&rdev->mutex);
1945         regulator->uA_load = 0;
1946         ret = _regulator_force_disable(regulator->rdev);
1947         mutex_unlock(&rdev->mutex);
1948
1949         if (rdev->supply)
1950                 while (rdev->open_count--)
1951                         regulator_disable(rdev->supply);
1952
1953         return ret;
1954 }
1955 EXPORT_SYMBOL_GPL(regulator_force_disable);
1956
1957 static void regulator_disable_work(struct work_struct *work)
1958 {
1959         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
1960                                                   disable_work.work);
1961         int count, i, ret;
1962
1963         mutex_lock(&rdev->mutex);
1964
1965         BUG_ON(!rdev->deferred_disables);
1966
1967         count = rdev->deferred_disables;
1968         rdev->deferred_disables = 0;
1969
1970         for (i = 0; i < count; i++) {
1971                 ret = _regulator_disable(rdev);
1972                 if (ret != 0)
1973                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
1974         }
1975
1976         mutex_unlock(&rdev->mutex);
1977
1978         if (rdev->supply) {
1979                 for (i = 0; i < count; i++) {
1980                         ret = regulator_disable(rdev->supply);
1981                         if (ret != 0) {
1982                                 rdev_err(rdev,
1983                                          "Supply disable failed: %d\n", ret);
1984                         }
1985                 }
1986         }
1987 }
1988
1989 /**
1990  * regulator_disable_deferred - disable regulator output with delay
1991  * @regulator: regulator source
1992  * @ms: miliseconds until the regulator is disabled
1993  *
1994  * Execute regulator_disable() on the regulator after a delay.  This
1995  * is intended for use with devices that require some time to quiesce.
1996  *
1997  * NOTE: this will only disable the regulator output if no other consumer
1998  * devices have it enabled, the regulator device supports disabling and
1999  * machine constraints permit this operation.
2000  */
2001 int regulator_disable_deferred(struct regulator *regulator, int ms)
2002 {
2003         struct regulator_dev *rdev = regulator->rdev;
2004         int ret;
2005
2006         if (regulator->always_on)
2007                 return 0;
2008
2009         if (!ms)
2010                 return regulator_disable(regulator);
2011
2012         mutex_lock(&rdev->mutex);
2013         rdev->deferred_disables++;
2014         mutex_unlock(&rdev->mutex);
2015
2016         ret = queue_delayed_work(system_power_efficient_wq,
2017                                  &rdev->disable_work,
2018                                  msecs_to_jiffies(ms));
2019         if (ret < 0)
2020                 return ret;
2021         else
2022                 return 0;
2023 }
2024 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2025
2026 static int _regulator_is_enabled(struct regulator_dev *rdev)
2027 {
2028         /* A GPIO control always takes precedence */
2029         if (rdev->ena_pin)
2030                 return rdev->ena_gpio_state;
2031
2032         /* If we don't know then assume that the regulator is always on */
2033         if (!rdev->desc->ops->is_enabled)
2034                 return 1;
2035
2036         return rdev->desc->ops->is_enabled(rdev);
2037 }
2038
2039 /**
2040  * regulator_is_enabled - is the regulator output enabled
2041  * @regulator: regulator source
2042  *
2043  * Returns positive if the regulator driver backing the source/client
2044  * has requested that the device be enabled, zero if it hasn't, else a
2045  * negative errno code.
2046  *
2047  * Note that the device backing this regulator handle can have multiple
2048  * users, so it might be enabled even if regulator_enable() was never
2049  * called for this particular source.
2050  */
2051 int regulator_is_enabled(struct regulator *regulator)
2052 {
2053         int ret;
2054
2055         if (regulator->always_on)
2056                 return 1;
2057
2058         mutex_lock(&regulator->rdev->mutex);
2059         ret = _regulator_is_enabled(regulator->rdev);
2060         mutex_unlock(&regulator->rdev->mutex);
2061
2062         return ret;
2063 }
2064 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2065
2066 /**
2067  * regulator_can_change_voltage - check if regulator can change voltage
2068  * @regulator: regulator source
2069  *
2070  * Returns positive if the regulator driver backing the source/client
2071  * can change its voltage, false otherwise. Usefull for detecting fixed
2072  * or dummy regulators and disabling voltage change logic in the client
2073  * driver.
2074  */
2075 int regulator_can_change_voltage(struct regulator *regulator)
2076 {
2077         struct regulator_dev    *rdev = regulator->rdev;
2078
2079         if (rdev->constraints &&
2080             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2081                 if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2082                         return 1;
2083
2084                 if (rdev->desc->continuous_voltage_range &&
2085                     rdev->constraints->min_uV && rdev->constraints->max_uV &&
2086                     rdev->constraints->min_uV != rdev->constraints->max_uV)
2087                         return 1;
2088         }
2089
2090         return 0;
2091 }
2092 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2093
2094 /**
2095  * regulator_count_voltages - count regulator_list_voltage() selectors
2096  * @regulator: regulator source
2097  *
2098  * Returns number of selectors, or negative errno.  Selectors are
2099  * numbered starting at zero, and typically correspond to bitfields
2100  * in hardware registers.
2101  */
2102 int regulator_count_voltages(struct regulator *regulator)
2103 {
2104         struct regulator_dev    *rdev = regulator->rdev;
2105
2106         return rdev->desc->n_voltages ? : -EINVAL;
2107 }
2108 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2109
2110 /**
2111  * regulator_list_voltage - enumerate supported voltages
2112  * @regulator: regulator source
2113  * @selector: identify voltage to list
2114  * Context: can sleep
2115  *
2116  * Returns a voltage that can be passed to @regulator_set_voltage(),
2117  * zero if this selector code can't be used on this system, or a
2118  * negative errno.
2119  */
2120 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2121 {
2122         struct regulator_dev    *rdev = regulator->rdev;
2123         struct regulator_ops    *ops = rdev->desc->ops;
2124         int                     ret;
2125
2126         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
2127                 return -EINVAL;
2128
2129         mutex_lock(&rdev->mutex);
2130         ret = ops->list_voltage(rdev, selector);
2131         mutex_unlock(&rdev->mutex);
2132
2133         if (ret > 0) {
2134                 if (ret < rdev->constraints->min_uV)
2135                         ret = 0;
2136                 else if (ret > rdev->constraints->max_uV)
2137                         ret = 0;
2138         }
2139
2140         return ret;
2141 }
2142 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2143
2144 /**
2145  * regulator_get_linear_step - return the voltage step size between VSEL values
2146  * @regulator: regulator source
2147  *
2148  * Returns the voltage step size between VSEL values for linear
2149  * regulators, or return 0 if the regulator isn't a linear regulator.
2150  */
2151 unsigned int regulator_get_linear_step(struct regulator *regulator)
2152 {
2153         struct regulator_dev *rdev = regulator->rdev;
2154
2155         return rdev->desc->uV_step;
2156 }
2157 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2158
2159 /**
2160  * regulator_is_supported_voltage - check if a voltage range can be supported
2161  *
2162  * @regulator: Regulator to check.
2163  * @min_uV: Minimum required voltage in uV.
2164  * @max_uV: Maximum required voltage in uV.
2165  *
2166  * Returns a boolean or a negative error code.
2167  */
2168 int regulator_is_supported_voltage(struct regulator *regulator,
2169                                    int min_uV, int max_uV)
2170 {
2171         struct regulator_dev *rdev = regulator->rdev;
2172         int i, voltages, ret;
2173
2174         /* If we can't change voltage check the current voltage */
2175         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2176                 ret = regulator_get_voltage(regulator);
2177                 if (ret >= 0)
2178                         return (min_uV <= ret && ret <= max_uV);
2179                 else
2180                         return ret;
2181         }
2182
2183         /* Any voltage within constrains range is fine? */
2184         if (rdev->desc->continuous_voltage_range)
2185                 return min_uV >= rdev->constraints->min_uV &&
2186                                 max_uV <= rdev->constraints->max_uV;
2187
2188         ret = regulator_count_voltages(regulator);
2189         if (ret < 0)
2190                 return ret;
2191         voltages = ret;
2192
2193         for (i = 0; i < voltages; i++) {
2194                 ret = regulator_list_voltage(regulator, i);
2195
2196                 if (ret >= min_uV && ret <= max_uV)
2197                         return 1;
2198         }
2199
2200         return 0;
2201 }
2202 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2203
2204 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2205                                      int min_uV, int max_uV)
2206 {
2207         int ret;
2208         int delay = 0;
2209         int best_val = 0;
2210         unsigned int selector;
2211         int old_selector = -1;
2212
2213         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2214
2215         min_uV += rdev->constraints->uV_offset;
2216         max_uV += rdev->constraints->uV_offset;
2217
2218         /*
2219          * If we can't obtain the old selector there is not enough
2220          * info to call set_voltage_time_sel().
2221          */
2222         if (_regulator_is_enabled(rdev) &&
2223             rdev->desc->ops->set_voltage_time_sel &&
2224             rdev->desc->ops->get_voltage_sel) {
2225                 old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2226                 if (old_selector < 0)
2227                         return old_selector;
2228         }
2229
2230         if (rdev->desc->ops->set_voltage) {
2231                 ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
2232                                                    &selector);
2233
2234                 if (ret >= 0) {
2235                         if (rdev->desc->ops->list_voltage)
2236                                 best_val = rdev->desc->ops->list_voltage(rdev,
2237                                                                          selector);
2238                         else
2239                                 best_val = _regulator_get_voltage(rdev);
2240                 }
2241
2242         } else if (rdev->desc->ops->set_voltage_sel) {
2243                 if (rdev->desc->ops->map_voltage) {
2244                         ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2245                                                            max_uV);
2246                 } else {
2247                         if (rdev->desc->ops->list_voltage ==
2248                             regulator_list_voltage_linear)
2249                                 ret = regulator_map_voltage_linear(rdev,
2250                                                                 min_uV, max_uV);
2251                         else
2252                                 ret = regulator_map_voltage_iterate(rdev,
2253                                                                 min_uV, max_uV);
2254                 }
2255
2256                 if (ret >= 0) {
2257                         best_val = rdev->desc->ops->list_voltage(rdev, ret);
2258                         if (min_uV <= best_val && max_uV >= best_val) {
2259                                 selector = ret;
2260                                 if (old_selector == selector)
2261                                         ret = 0;
2262                                 else
2263                                         ret = rdev->desc->ops->set_voltage_sel(
2264                                                                 rdev, ret);
2265                         } else {
2266                                 ret = -EINVAL;
2267                         }
2268                 }
2269         } else {
2270                 ret = -EINVAL;
2271         }
2272
2273         /* Call set_voltage_time_sel if successfully obtained old_selector */
2274         if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2275                 && old_selector != selector) {
2276
2277                 delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2278                                                 old_selector, selector);
2279                 if (delay < 0) {
2280                         rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2281                                   delay);
2282                         delay = 0;
2283                 }
2284
2285                 /* Insert any necessary delays */
2286                 if (delay >= 1000) {
2287                         mdelay(delay / 1000);
2288                         udelay(delay % 1000);
2289                 } else if (delay) {
2290                         udelay(delay);
2291                 }
2292         }
2293
2294         if (ret == 0 && best_val >= 0) {
2295                 unsigned long data = best_val;
2296
2297                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2298                                      (void *)data);
2299         }
2300
2301         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2302
2303         return ret;
2304 }
2305
2306 /**
2307  * regulator_set_voltage - set regulator output voltage
2308  * @regulator: regulator source
2309  * @min_uV: Minimum required voltage in uV
2310  * @max_uV: Maximum acceptable voltage in uV
2311  *
2312  * Sets a voltage regulator to the desired output voltage. This can be set
2313  * during any regulator state. IOW, regulator can be disabled or enabled.
2314  *
2315  * If the regulator is enabled then the voltage will change to the new value
2316  * immediately otherwise if the regulator is disabled the regulator will
2317  * output at the new voltage when enabled.
2318  *
2319  * NOTE: If the regulator is shared between several devices then the lowest
2320  * request voltage that meets the system constraints will be used.
2321  * Regulator system constraints must be set for this regulator before
2322  * calling this function otherwise this call will fail.
2323  */
2324 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2325 {
2326         struct regulator_dev *rdev = regulator->rdev;
2327         int ret = 0;
2328         int old_min_uV, old_max_uV;
2329
2330         mutex_lock(&rdev->mutex);
2331
2332         /* If we're setting the same range as last time the change
2333          * should be a noop (some cpufreq implementations use the same
2334          * voltage for multiple frequencies, for example).
2335          */
2336         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2337                 goto out;
2338
2339         /* sanity check */
2340         if (!rdev->desc->ops->set_voltage &&
2341             !rdev->desc->ops->set_voltage_sel) {
2342                 ret = -EINVAL;
2343                 goto out;
2344         }
2345
2346         /* constraints check */
2347         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2348         if (ret < 0)
2349                 goto out;
2350
2351         /* restore original values in case of error */
2352         old_min_uV = regulator->min_uV;
2353         old_max_uV = regulator->max_uV;
2354         regulator->min_uV = min_uV;
2355         regulator->max_uV = max_uV;
2356
2357         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2358         if (ret < 0)
2359                 goto out2;
2360
2361         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2362         if (ret < 0)
2363                 goto out2;
2364
2365 out:
2366         mutex_unlock(&rdev->mutex);
2367         return ret;
2368 out2:
2369         regulator->min_uV = old_min_uV;
2370         regulator->max_uV = old_max_uV;
2371         mutex_unlock(&rdev->mutex);
2372         return ret;
2373 }
2374 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2375
2376 /**
2377  * regulator_set_voltage_time - get raise/fall time
2378  * @regulator: regulator source
2379  * @old_uV: starting voltage in microvolts
2380  * @new_uV: target voltage in microvolts
2381  *
2382  * Provided with the starting and ending voltage, this function attempts to
2383  * calculate the time in microseconds required to rise or fall to this new
2384  * voltage.
2385  */
2386 int regulator_set_voltage_time(struct regulator *regulator,
2387                                int old_uV, int new_uV)
2388 {
2389         struct regulator_dev    *rdev = regulator->rdev;
2390         struct regulator_ops    *ops = rdev->desc->ops;
2391         int old_sel = -1;
2392         int new_sel = -1;
2393         int voltage;
2394         int i;
2395
2396         /* Currently requires operations to do this */
2397         if (!ops->list_voltage || !ops->set_voltage_time_sel
2398             || !rdev->desc->n_voltages)
2399                 return -EINVAL;
2400
2401         for (i = 0; i < rdev->desc->n_voltages; i++) {
2402                 /* We only look for exact voltage matches here */
2403                 voltage = regulator_list_voltage(regulator, i);
2404                 if (voltage < 0)
2405                         return -EINVAL;
2406                 if (voltage == 0)
2407                         continue;
2408                 if (voltage == old_uV)
2409                         old_sel = i;
2410                 if (voltage == new_uV)
2411                         new_sel = i;
2412         }
2413
2414         if (old_sel < 0 || new_sel < 0)
2415                 return -EINVAL;
2416
2417         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2418 }
2419 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2420
2421 /**
2422  * regulator_set_voltage_time_sel - get raise/fall time
2423  * @rdev: regulator source device
2424  * @old_selector: selector for starting voltage
2425  * @new_selector: selector for target voltage
2426  *
2427  * Provided with the starting and target voltage selectors, this function
2428  * returns time in microseconds required to rise or fall to this new voltage
2429  *
2430  * Drivers providing ramp_delay in regulation_constraints can use this as their
2431  * set_voltage_time_sel() operation.
2432  */
2433 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2434                                    unsigned int old_selector,
2435                                    unsigned int new_selector)
2436 {
2437         unsigned int ramp_delay = 0;
2438         int old_volt, new_volt;
2439
2440         if (rdev->constraints->ramp_delay)
2441                 ramp_delay = rdev->constraints->ramp_delay;
2442         else if (rdev->desc->ramp_delay)
2443                 ramp_delay = rdev->desc->ramp_delay;
2444
2445         if (ramp_delay == 0) {
2446                 rdev_warn(rdev, "ramp_delay not set\n");
2447                 return 0;
2448         }
2449
2450         /* sanity check */
2451         if (!rdev->desc->ops->list_voltage)
2452                 return -EINVAL;
2453
2454         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2455         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2456
2457         return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2458 }
2459 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2460
2461 /**
2462  * regulator_sync_voltage - re-apply last regulator output voltage
2463  * @regulator: regulator source
2464  *
2465  * Re-apply the last configured voltage.  This is intended to be used
2466  * where some external control source the consumer is cooperating with
2467  * has caused the configured voltage to change.
2468  */
2469 int regulator_sync_voltage(struct regulator *regulator)
2470 {
2471         struct regulator_dev *rdev = regulator->rdev;
2472         int ret, min_uV, max_uV;
2473
2474         mutex_lock(&rdev->mutex);
2475
2476         if (!rdev->desc->ops->set_voltage &&
2477             !rdev->desc->ops->set_voltage_sel) {
2478                 ret = -EINVAL;
2479                 goto out;
2480         }
2481
2482         /* This is only going to work if we've had a voltage configured. */
2483         if (!regulator->min_uV && !regulator->max_uV) {
2484                 ret = -EINVAL;
2485                 goto out;
2486         }
2487
2488         min_uV = regulator->min_uV;
2489         max_uV = regulator->max_uV;
2490
2491         /* This should be a paranoia check... */
2492         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2493         if (ret < 0)
2494                 goto out;
2495
2496         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2497         if (ret < 0)
2498                 goto out;
2499
2500         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2501
2502 out:
2503         mutex_unlock(&rdev->mutex);
2504         return ret;
2505 }
2506 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2507
2508 static int _regulator_get_voltage(struct regulator_dev *rdev)
2509 {
2510         int sel, ret;
2511
2512         if (rdev->desc->ops->get_voltage_sel) {
2513                 sel = rdev->desc->ops->get_voltage_sel(rdev);
2514                 if (sel < 0)
2515                         return sel;
2516                 ret = rdev->desc->ops->list_voltage(rdev, sel);
2517         } else if (rdev->desc->ops->get_voltage) {
2518                 ret = rdev->desc->ops->get_voltage(rdev);
2519         } else if (rdev->desc->ops->list_voltage) {
2520                 ret = rdev->desc->ops->list_voltage(rdev, 0);
2521         } else {
2522                 return -EINVAL;
2523         }
2524
2525         if (ret < 0)
2526                 return ret;
2527         return ret - rdev->constraints->uV_offset;
2528 }
2529
2530 /**
2531  * regulator_get_voltage - get regulator output voltage
2532  * @regulator: regulator source
2533  *
2534  * This returns the current regulator voltage in uV.
2535  *
2536  * NOTE: If the regulator is disabled it will return the voltage value. This
2537  * function should not be used to determine regulator state.
2538  */
2539 int regulator_get_voltage(struct regulator *regulator)
2540 {
2541         int ret;
2542
2543         mutex_lock(&regulator->rdev->mutex);
2544
2545         ret = _regulator_get_voltage(regulator->rdev);
2546
2547         mutex_unlock(&regulator->rdev->mutex);
2548
2549         return ret;
2550 }
2551 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2552
2553 /**
2554  * regulator_set_current_limit - set regulator output current limit
2555  * @regulator: regulator source
2556  * @min_uA: Minimum supported current in uA
2557  * @max_uA: Maximum supported current in uA
2558  *
2559  * Sets current sink to the desired output current. This can be set during
2560  * any regulator state. IOW, regulator can be disabled or enabled.
2561  *
2562  * If the regulator is enabled then the current will change to the new value
2563  * immediately otherwise if the regulator is disabled the regulator will
2564  * output at the new current when enabled.
2565  *
2566  * NOTE: Regulator system constraints must be set for this regulator before
2567  * calling this function otherwise this call will fail.
2568  */
2569 int regulator_set_current_limit(struct regulator *regulator,
2570                                int min_uA, int max_uA)
2571 {
2572         struct regulator_dev *rdev = regulator->rdev;
2573         int ret;
2574
2575         mutex_lock(&rdev->mutex);
2576
2577         /* sanity check */
2578         if (!rdev->desc->ops->set_current_limit) {
2579                 ret = -EINVAL;
2580                 goto out;
2581         }
2582
2583         /* constraints check */
2584         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2585         if (ret < 0)
2586                 goto out;
2587
2588         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2589 out:
2590         mutex_unlock(&rdev->mutex);
2591         return ret;
2592 }
2593 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2594
2595 static int _regulator_get_current_limit(struct regulator_dev *rdev)
2596 {
2597         int ret;
2598
2599         mutex_lock(&rdev->mutex);
2600
2601         /* sanity check */
2602         if (!rdev->desc->ops->get_current_limit) {
2603                 ret = -EINVAL;
2604                 goto out;
2605         }
2606
2607         ret = rdev->desc->ops->get_current_limit(rdev);
2608 out:
2609         mutex_unlock(&rdev->mutex);
2610         return ret;
2611 }
2612
2613 /**
2614  * regulator_get_current_limit - get regulator output current
2615  * @regulator: regulator source
2616  *
2617  * This returns the current supplied by the specified current sink in uA.
2618  *
2619  * NOTE: If the regulator is disabled it will return the current value. This
2620  * function should not be used to determine regulator state.
2621  */
2622 int regulator_get_current_limit(struct regulator *regulator)
2623 {
2624         return _regulator_get_current_limit(regulator->rdev);
2625 }
2626 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
2627
2628 /**
2629  * regulator_set_mode - set regulator operating mode
2630  * @regulator: regulator source
2631  * @mode: operating mode - one of the REGULATOR_MODE constants
2632  *
2633  * Set regulator operating mode to increase regulator efficiency or improve
2634  * regulation performance.
2635  *
2636  * NOTE: Regulator system constraints must be set for this regulator before
2637  * calling this function otherwise this call will fail.
2638  */
2639 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2640 {
2641         struct regulator_dev *rdev = regulator->rdev;
2642         int ret;
2643         int regulator_curr_mode;
2644
2645         mutex_lock(&rdev->mutex);
2646
2647         /* sanity check */
2648         if (!rdev->desc->ops->set_mode) {
2649                 ret = -EINVAL;
2650                 goto out;
2651         }
2652
2653         /* return if the same mode is requested */
2654         if (rdev->desc->ops->get_mode) {
2655                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2656                 if (regulator_curr_mode == mode) {
2657                         ret = 0;
2658                         goto out;
2659                 }
2660         }
2661
2662         /* constraints check */
2663         ret = regulator_mode_constrain(rdev, &mode);
2664         if (ret < 0)
2665                 goto out;
2666
2667         ret = rdev->desc->ops->set_mode(rdev, mode);
2668 out:
2669         mutex_unlock(&rdev->mutex);
2670         return ret;
2671 }
2672 EXPORT_SYMBOL_GPL(regulator_set_mode);
2673
2674 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2675 {
2676         int ret;
2677
2678         mutex_lock(&rdev->mutex);
2679
2680         /* sanity check */
2681         if (!rdev->desc->ops->get_mode) {
2682                 ret = -EINVAL;
2683                 goto out;
2684         }
2685
2686         ret = rdev->desc->ops->get_mode(rdev);
2687 out:
2688         mutex_unlock(&rdev->mutex);
2689         return ret;
2690 }
2691
2692 /**
2693  * regulator_get_mode - get regulator operating mode
2694  * @regulator: regulator source
2695  *
2696  * Get the current regulator operating mode.
2697  */
2698 unsigned int regulator_get_mode(struct regulator *regulator)
2699 {
2700         return _regulator_get_mode(regulator->rdev);
2701 }
2702 EXPORT_SYMBOL_GPL(regulator_get_mode);
2703
2704 /**
2705  * regulator_set_optimum_mode - set regulator optimum operating mode
2706  * @regulator: regulator source
2707  * @uA_load: load current
2708  *
2709  * Notifies the regulator core of a new device load. This is then used by
2710  * DRMS (if enabled by constraints) to set the most efficient regulator
2711  * operating mode for the new regulator loading.
2712  *
2713  * Consumer devices notify their supply regulator of the maximum power
2714  * they will require (can be taken from device datasheet in the power
2715  * consumption tables) when they change operational status and hence power
2716  * state. Examples of operational state changes that can affect power
2717  * consumption are :-
2718  *
2719  *    o Device is opened / closed.
2720  *    o Device I/O is about to begin or has just finished.
2721  *    o Device is idling in between work.
2722  *
2723  * This information is also exported via sysfs to userspace.
2724  *
2725  * DRMS will sum the total requested load on the regulator and change
2726  * to the most efficient operating mode if platform constraints allow.
2727  *
2728  * Returns the new regulator mode or error.
2729  */
2730 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
2731 {
2732         struct regulator_dev *rdev = regulator->rdev;
2733         struct regulator *consumer;
2734         int ret, output_uV, input_uV = 0, total_uA_load = 0;
2735         unsigned int mode;
2736
2737         if (rdev->supply)
2738                 input_uV = regulator_get_voltage(rdev->supply);
2739
2740         mutex_lock(&rdev->mutex);
2741
2742         /*
2743          * first check to see if we can set modes at all, otherwise just
2744          * tell the consumer everything is OK.
2745          */
2746         regulator->uA_load = uA_load;
2747         ret = regulator_check_drms(rdev);
2748         if (ret < 0) {
2749                 ret = 0;
2750                 goto out;
2751         }
2752
2753         if (!rdev->desc->ops->get_optimum_mode)
2754                 goto out;
2755
2756         /*
2757          * we can actually do this so any errors are indicators of
2758          * potential real failure.
2759          */
2760         ret = -EINVAL;
2761
2762         if (!rdev->desc->ops->set_mode)
2763                 goto out;
2764
2765         /* get output voltage */
2766         output_uV = _regulator_get_voltage(rdev);
2767         if (output_uV <= 0) {
2768                 rdev_err(rdev, "invalid output voltage found\n");
2769                 goto out;
2770         }
2771
2772         /* No supply? Use constraint voltage */
2773         if (input_uV <= 0)
2774                 input_uV = rdev->constraints->input_uV;
2775         if (input_uV <= 0) {
2776                 rdev_err(rdev, "invalid input voltage found\n");
2777                 goto out;
2778         }
2779
2780         /* calc total requested load for this regulator */
2781         list_for_each_entry(consumer, &rdev->consumer_list, list)
2782                 total_uA_load += consumer->uA_load;
2783
2784         mode = rdev->desc->ops->get_optimum_mode(rdev,
2785                                                  input_uV, output_uV,
2786                                                  total_uA_load);
2787         ret = regulator_mode_constrain(rdev, &mode);
2788         if (ret < 0) {
2789                 rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
2790                          total_uA_load, input_uV, output_uV);
2791                 goto out;
2792         }
2793
2794         ret = rdev->desc->ops->set_mode(rdev, mode);
2795         if (ret < 0) {
2796                 rdev_err(rdev, "failed to set optimum mode %x\n", mode);
2797                 goto out;
2798         }
2799         ret = mode;
2800 out:
2801         mutex_unlock(&rdev->mutex);
2802         return ret;
2803 }
2804 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
2805
2806 /**
2807  * regulator_allow_bypass - allow the regulator to go into bypass mode
2808  *
2809  * @regulator: Regulator to configure
2810  * @enable: enable or disable bypass mode
2811  *
2812  * Allow the regulator to go into bypass mode if all other consumers
2813  * for the regulator also enable bypass mode and the machine
2814  * constraints allow this.  Bypass mode means that the regulator is
2815  * simply passing the input directly to the output with no regulation.
2816  */
2817 int regulator_allow_bypass(struct regulator *regulator, bool enable)
2818 {
2819         struct regulator_dev *rdev = regulator->rdev;
2820         int ret = 0;
2821
2822         if (!rdev->desc->ops->set_bypass)
2823                 return 0;
2824
2825         if (rdev->constraints &&
2826             !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
2827                 return 0;
2828
2829         mutex_lock(&rdev->mutex);
2830
2831         if (enable && !regulator->bypass) {
2832                 rdev->bypass_count++;
2833
2834                 if (rdev->bypass_count == rdev->open_count) {
2835                         ret = rdev->desc->ops->set_bypass(rdev, enable);
2836                         if (ret != 0)
2837                                 rdev->bypass_count--;
2838                 }
2839
2840         } else if (!enable && regulator->bypass) {
2841                 rdev->bypass_count--;
2842
2843                 if (rdev->bypass_count != rdev->open_count) {
2844                         ret = rdev->desc->ops->set_bypass(rdev, enable);
2845                         if (ret != 0)
2846                                 rdev->bypass_count++;
2847                 }
2848         }
2849
2850         if (ret == 0)
2851                 regulator->bypass = enable;
2852
2853         mutex_unlock(&rdev->mutex);
2854
2855         return ret;
2856 }
2857 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
2858
2859 /**
2860  * regulator_register_notifier - register regulator event notifier
2861  * @regulator: regulator source
2862  * @nb: notifier block
2863  *
2864  * Register notifier block to receive regulator events.
2865  */
2866 int regulator_register_notifier(struct regulator *regulator,
2867                               struct notifier_block *nb)
2868 {
2869         return blocking_notifier_chain_register(&regulator->rdev->notifier,
2870                                                 nb);
2871 }
2872 EXPORT_SYMBOL_GPL(regulator_register_notifier);
2873
2874 /**
2875  * regulator_unregister_notifier - unregister regulator event notifier
2876  * @regulator: regulator source
2877  * @nb: notifier block
2878  *
2879  * Unregister regulator event notifier block.
2880  */
2881 int regulator_unregister_notifier(struct regulator *regulator,
2882                                 struct notifier_block *nb)
2883 {
2884         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
2885                                                   nb);
2886 }
2887 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
2888
2889 /* notify regulator consumers and downstream regulator consumers.
2890  * Note mutex must be held by caller.
2891  */
2892 static void _notifier_call_chain(struct regulator_dev *rdev,
2893                                   unsigned long event, void *data)
2894 {
2895         /* call rdev chain first */
2896         blocking_notifier_call_chain(&rdev->notifier, event, data);
2897 }
2898
2899 /**
2900  * regulator_bulk_get - get multiple regulator consumers
2901  *
2902  * @dev:           Device to supply
2903  * @num_consumers: Number of consumers to register
2904  * @consumers:     Configuration of consumers; clients are stored here.
2905  *
2906  * @return 0 on success, an errno on failure.
2907  *
2908  * This helper function allows drivers to get several regulator
2909  * consumers in one operation.  If any of the regulators cannot be
2910  * acquired then any regulators that were allocated will be freed
2911  * before returning to the caller.
2912  */
2913 int regulator_bulk_get(struct device *dev, int num_consumers,
2914                        struct regulator_bulk_data *consumers)
2915 {
2916         int i;
2917         int ret;
2918
2919         for (i = 0; i < num_consumers; i++)
2920                 consumers[i].consumer = NULL;
2921
2922         for (i = 0; i < num_consumers; i++) {
2923                 consumers[i].consumer = regulator_get(dev,
2924                                                       consumers[i].supply);
2925                 if (IS_ERR(consumers[i].consumer)) {
2926                         ret = PTR_ERR(consumers[i].consumer);
2927                         dev_err(dev, "Failed to get supply '%s': %d\n",
2928                                 consumers[i].supply, ret);
2929                         consumers[i].consumer = NULL;
2930                         goto err;
2931                 }
2932         }
2933
2934         return 0;
2935
2936 err:
2937         while (--i >= 0)
2938                 regulator_put(consumers[i].consumer);
2939
2940         return ret;
2941 }
2942 EXPORT_SYMBOL_GPL(regulator_bulk_get);
2943
2944 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
2945 {
2946         struct regulator_bulk_data *bulk = data;
2947
2948         bulk->ret = regulator_enable(bulk->consumer);
2949 }
2950
2951 /**
2952  * regulator_bulk_enable - enable multiple regulator consumers
2953  *
2954  * @num_consumers: Number of consumers
2955  * @consumers:     Consumer data; clients are stored here.
2956  * @return         0 on success, an errno on failure
2957  *
2958  * This convenience API allows consumers to enable multiple regulator
2959  * clients in a single API call.  If any consumers cannot be enabled
2960  * then any others that were enabled will be disabled again prior to
2961  * return.
2962  */
2963 int regulator_bulk_enable(int num_consumers,
2964                           struct regulator_bulk_data *consumers)
2965 {
2966         ASYNC_DOMAIN_EXCLUSIVE(async_domain);
2967         int i;
2968         int ret = 0;
2969
2970         for (i = 0; i < num_consumers; i++) {
2971                 if (consumers[i].consumer->always_on)
2972                         consumers[i].ret = 0;
2973                 else
2974                         async_schedule_domain(regulator_bulk_enable_async,
2975                                               &consumers[i], &async_domain);
2976         }
2977
2978         async_synchronize_full_domain(&async_domain);
2979
2980         /* If any consumer failed we need to unwind any that succeeded */
2981         for (i = 0; i < num_consumers; i++) {
2982                 if (consumers[i].ret != 0) {
2983                         ret = consumers[i].ret;
2984                         goto err;
2985                 }
2986         }
2987
2988         return 0;
2989
2990 err:
2991         for (i = 0; i < num_consumers; i++) {
2992                 if (consumers[i].ret < 0)
2993                         pr_err("Failed to enable %s: %d\n", consumers[i].supply,
2994                                consumers[i].ret);
2995                 else
2996                         regulator_disable(consumers[i].consumer);
2997         }
2998
2999         return ret;
3000 }
3001 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
3002
3003 /**
3004  * regulator_bulk_disable - disable multiple regulator consumers
3005  *
3006  * @num_consumers: Number of consumers
3007  * @consumers:     Consumer data; clients are stored here.
3008  * @return         0 on success, an errno on failure
3009  *
3010  * This convenience API allows consumers to disable multiple regulator
3011  * clients in a single API call.  If any consumers cannot be disabled
3012  * then any others that were disabled will be enabled again prior to
3013  * return.
3014  */
3015 int regulator_bulk_disable(int num_consumers,
3016                            struct regulator_bulk_data *consumers)
3017 {
3018         int i;
3019         int ret, r;
3020
3021         for (i = num_consumers - 1; i >= 0; --i) {
3022                 ret = regulator_disable(consumers[i].consumer);
3023                 if (ret != 0)
3024                         goto err;
3025         }
3026
3027         return 0;
3028
3029 err:
3030         pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
3031         for (++i; i < num_consumers; ++i) {
3032                 r = regulator_enable(consumers[i].consumer);
3033                 if (r != 0)
3034                         pr_err("Failed to reename %s: %d\n",
3035                                consumers[i].supply, r);
3036         }
3037
3038         return ret;
3039 }
3040 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
3041
3042 /**
3043  * regulator_bulk_force_disable - force disable multiple regulator consumers
3044  *
3045  * @num_consumers: Number of consumers
3046  * @consumers:     Consumer data; clients are stored here.
3047  * @return         0 on success, an errno on failure
3048  *
3049  * This convenience API allows consumers to forcibly disable multiple regulator
3050  * clients in a single API call.
3051  * NOTE: This should be used for situations when device damage will
3052  * likely occur if the regulators are not disabled (e.g. over temp).
3053  * Although regulator_force_disable function call for some consumers can
3054  * return error numbers, the function is called for all consumers.
3055  */
3056 int regulator_bulk_force_disable(int num_consumers,
3057                            struct regulator_bulk_data *consumers)
3058 {
3059         int i;
3060         int ret;
3061
3062         for (i = 0; i < num_consumers; i++)
3063                 consumers[i].ret =
3064                             regulator_force_disable(consumers[i].consumer);
3065
3066         for (i = 0; i < num_consumers; i++) {
3067                 if (consumers[i].ret != 0) {
3068                         ret = consumers[i].ret;
3069                         goto out;
3070                 }
3071         }
3072
3073         return 0;
3074 out:
3075         return ret;
3076 }
3077 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
3078
3079 /**
3080  * regulator_bulk_free - free multiple regulator consumers
3081  *
3082  * @num_consumers: Number of consumers
3083  * @consumers:     Consumer data; clients are stored here.
3084  *
3085  * This convenience API allows consumers to free multiple regulator
3086  * clients in a single API call.
3087  */
3088 void regulator_bulk_free(int num_consumers,
3089                          struct regulator_bulk_data *consumers)
3090 {
3091         int i;
3092
3093         for (i = 0; i < num_consumers; i++) {
3094                 regulator_put(consumers[i].consumer);
3095                 consumers[i].consumer = NULL;
3096         }
3097 }
3098 EXPORT_SYMBOL_GPL(regulator_bulk_free);
3099
3100 /**
3101  * regulator_notifier_call_chain - call regulator event notifier
3102  * @rdev: regulator source
3103  * @event: notifier block
3104  * @data: callback-specific data.
3105  *
3106  * Called by regulator drivers to notify clients a regulator event has
3107  * occurred. We also notify regulator clients downstream.
3108  * Note lock must be held by caller.
3109  */
3110 int regulator_notifier_call_chain(struct regulator_dev *rdev,
3111                                   unsigned long event, void *data)
3112 {
3113         _notifier_call_chain(rdev, event, data);
3114         return NOTIFY_DONE;
3115
3116 }
3117 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
3118
3119 /**
3120  * regulator_mode_to_status - convert a regulator mode into a status
3121  *
3122  * @mode: Mode to convert
3123  *
3124  * Convert a regulator mode into a status.
3125  */
3126 int regulator_mode_to_status(unsigned int mode)
3127 {
3128         switch (mode) {
3129         case REGULATOR_MODE_FAST:
3130                 return REGULATOR_STATUS_FAST;
3131         case REGULATOR_MODE_NORMAL:
3132                 return REGULATOR_STATUS_NORMAL;
3133         case REGULATOR_MODE_IDLE:
3134                 return REGULATOR_STATUS_IDLE;
3135         case REGULATOR_MODE_STANDBY:
3136                 return REGULATOR_STATUS_STANDBY;
3137         default:
3138                 return REGULATOR_STATUS_UNDEFINED;
3139         }
3140 }
3141 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3142
3143 /*
3144  * To avoid cluttering sysfs (and memory) with useless state, only
3145  * create attributes that can be meaningfully displayed.
3146  */
3147 static int add_regulator_attributes(struct regulator_dev *rdev)
3148 {
3149         struct device           *dev = &rdev->dev;
3150         struct regulator_ops    *ops = rdev->desc->ops;
3151         int                     status = 0;
3152
3153         /* some attributes need specific methods to be displayed */
3154         if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3155             (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
3156             (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0)) {
3157                 status = device_create_file(dev, &dev_attr_microvolts);
3158                 if (status < 0)
3159                         return status;
3160         }
3161         if (ops->get_current_limit) {
3162                 status = device_create_file(dev, &dev_attr_microamps);
3163                 if (status < 0)
3164                         return status;
3165         }
3166         if (ops->get_mode) {
3167                 status = device_create_file(dev, &dev_attr_opmode);
3168                 if (status < 0)
3169                         return status;
3170         }
3171         if (rdev->ena_pin || ops->is_enabled) {
3172                 status = device_create_file(dev, &dev_attr_state);
3173                 if (status < 0)
3174                         return status;
3175         }
3176         if (ops->get_status) {
3177                 status = device_create_file(dev, &dev_attr_status);
3178                 if (status < 0)
3179                         return status;
3180         }
3181         if (ops->get_bypass) {
3182                 status = device_create_file(dev, &dev_attr_bypass);
3183                 if (status < 0)
3184                         return status;
3185         }
3186
3187         /* some attributes are type-specific */
3188         if (rdev->desc->type == REGULATOR_CURRENT) {
3189                 status = device_create_file(dev, &dev_attr_requested_microamps);
3190                 if (status < 0)
3191                         return status;
3192         }
3193
3194         /* all the other attributes exist to support constraints;
3195          * don't show them if there are no constraints, or if the
3196          * relevant supporting methods are missing.
3197          */
3198         if (!rdev->constraints)
3199                 return status;
3200
3201         /* constraints need specific supporting methods */
3202         if (ops->set_voltage || ops->set_voltage_sel) {
3203                 status = device_create_file(dev, &dev_attr_min_microvolts);
3204                 if (status < 0)
3205                         return status;
3206                 status = device_create_file(dev, &dev_attr_max_microvolts);
3207                 if (status < 0)
3208                         return status;
3209         }
3210         if (ops->set_current_limit) {
3211                 status = device_create_file(dev, &dev_attr_min_microamps);
3212                 if (status < 0)
3213                         return status;
3214                 status = device_create_file(dev, &dev_attr_max_microamps);
3215                 if (status < 0)
3216                         return status;
3217         }
3218
3219         status = device_create_file(dev, &dev_attr_suspend_standby_state);
3220         if (status < 0)
3221                 return status;
3222         status = device_create_file(dev, &dev_attr_suspend_mem_state);
3223         if (status < 0)
3224                 return status;
3225         status = device_create_file(dev, &dev_attr_suspend_disk_state);
3226         if (status < 0)
3227                 return status;
3228
3229         if (ops->set_suspend_voltage) {
3230                 status = device_create_file(dev,
3231                                 &dev_attr_suspend_standby_microvolts);
3232                 if (status < 0)
3233                         return status;
3234                 status = device_create_file(dev,
3235                                 &dev_attr_suspend_mem_microvolts);
3236                 if (status < 0)
3237                         return status;
3238                 status = device_create_file(dev,
3239                                 &dev_attr_suspend_disk_microvolts);
3240                 if (status < 0)
3241                         return status;
3242         }
3243
3244         if (ops->set_suspend_mode) {
3245                 status = device_create_file(dev,
3246                                 &dev_attr_suspend_standby_mode);
3247                 if (status < 0)
3248                         return status;
3249                 status = device_create_file(dev,
3250                                 &dev_attr_suspend_mem_mode);
3251                 if (status < 0)
3252                         return status;
3253                 status = device_create_file(dev,
3254                                 &dev_attr_suspend_disk_mode);
3255                 if (status < 0)
3256                         return status;
3257         }
3258
3259         return status;
3260 }
3261
3262 static void rdev_init_debugfs(struct regulator_dev *rdev)
3263 {
3264         rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
3265         if (!rdev->debugfs) {
3266                 rdev_warn(rdev, "Failed to create debugfs directory\n");
3267                 return;
3268         }
3269
3270         debugfs_create_u32("use_count", 0444, rdev->debugfs,
3271                            &rdev->use_count);
3272         debugfs_create_u32("open_count", 0444, rdev->debugfs,
3273                            &rdev->open_count);
3274         debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
3275                            &rdev->bypass_count);
3276 }
3277
3278 /**
3279  * regulator_register - register regulator
3280  * @regulator_desc: regulator to register
3281  * @config: runtime configuration for regulator
3282  *
3283  * Called by regulator drivers to register a regulator.
3284  * Returns a valid pointer to struct regulator_dev on success
3285  * or an ERR_PTR() on error.
3286  */
3287 struct regulator_dev *
3288 regulator_register(const struct regulator_desc *regulator_desc,
3289                    const struct regulator_config *config)
3290 {
3291         const struct regulation_constraints *constraints = NULL;
3292         const struct regulator_init_data *init_data;
3293         static atomic_t regulator_no = ATOMIC_INIT(0);
3294         struct regulator_dev *rdev;
3295         struct device *dev;
3296         int ret, i;
3297         const char *supply = NULL;
3298
3299         if (regulator_desc == NULL || config == NULL)
3300                 return ERR_PTR(-EINVAL);
3301
3302         dev = config->dev;
3303         WARN_ON(!dev);
3304
3305         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3306                 return ERR_PTR(-EINVAL);
3307
3308         if (regulator_desc->type != REGULATOR_VOLTAGE &&
3309             regulator_desc->type != REGULATOR_CURRENT)
3310                 return ERR_PTR(-EINVAL);
3311
3312         /* Only one of each should be implemented */
3313         WARN_ON(regulator_desc->ops->get_voltage &&
3314                 regulator_desc->ops->get_voltage_sel);
3315         WARN_ON(regulator_desc->ops->set_voltage &&
3316                 regulator_desc->ops->set_voltage_sel);
3317
3318         /* If we're using selectors we must implement list_voltage. */
3319         if (regulator_desc->ops->get_voltage_sel &&
3320             !regulator_desc->ops->list_voltage) {
3321                 return ERR_PTR(-EINVAL);
3322         }
3323         if (regulator_desc->ops->set_voltage_sel &&
3324             !regulator_desc->ops->list_voltage) {
3325                 return ERR_PTR(-EINVAL);
3326         }
3327
3328         init_data = config->init_data;
3329
3330         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3331         if (rdev == NULL)
3332                 return ERR_PTR(-ENOMEM);
3333
3334         mutex_lock(&regulator_list_mutex);
3335
3336         mutex_init(&rdev->mutex);
3337         rdev->reg_data = config->driver_data;
3338         rdev->owner = regulator_desc->owner;
3339         rdev->desc = regulator_desc;
3340         if (config->regmap)
3341                 rdev->regmap = config->regmap;
3342         else if (dev_get_regmap(dev, NULL))
3343                 rdev->regmap = dev_get_regmap(dev, NULL);
3344         else if (dev->parent)
3345                 rdev->regmap = dev_get_regmap(dev->parent, NULL);
3346         INIT_LIST_HEAD(&rdev->consumer_list);
3347         INIT_LIST_HEAD(&rdev->list);
3348         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3349         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3350
3351         /* preform any regulator specific init */
3352         if (init_data && init_data->regulator_init) {
3353                 ret = init_data->regulator_init(rdev->reg_data);
3354                 if (ret < 0)
3355                         goto clean;
3356         }
3357
3358         /* register with sysfs */
3359         rdev->dev.class = &regulator_class;
3360         rdev->dev.of_node = config->of_node;
3361         rdev->dev.parent = dev;
3362         dev_set_name(&rdev->dev, "regulator.%d",
3363                      atomic_inc_return(&regulator_no) - 1);
3364         ret = device_register(&rdev->dev);
3365         if (ret != 0) {
3366                 put_device(&rdev->dev);
3367                 goto clean;
3368         }
3369
3370         dev_set_drvdata(&rdev->dev, rdev);
3371
3372         if (config->ena_gpio && gpio_is_valid(config->ena_gpio)) {
3373                 ret = regulator_ena_gpio_request(rdev, config);
3374                 if (ret != 0) {
3375                         rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3376                                  config->ena_gpio, ret);
3377                         goto wash;
3378                 }
3379
3380                 if (config->ena_gpio_flags & GPIOF_OUT_INIT_HIGH)
3381                         rdev->ena_gpio_state = 1;
3382
3383                 if (config->ena_gpio_invert)
3384                         rdev->ena_gpio_state = !rdev->ena_gpio_state;
3385         }
3386
3387         /* set regulator constraints */
3388         if (init_data)
3389                 constraints = &init_data->constraints;
3390
3391         ret = set_machine_constraints(rdev, constraints);
3392         if (ret < 0)
3393                 goto scrub;
3394
3395         /* add attributes supported by this regulator */
3396         ret = add_regulator_attributes(rdev);
3397         if (ret < 0)
3398                 goto scrub;
3399
3400         if (init_data && init_data->supply_regulator)
3401                 supply = init_data->supply_regulator;
3402         else if (regulator_desc->supply_name)
3403                 supply = regulator_desc->supply_name;
3404
3405         if (supply) {
3406                 struct regulator_dev *r;
3407
3408                 r = regulator_dev_lookup(dev, supply, &ret);
3409
3410                 if (ret == -ENODEV) {
3411                         /*
3412                          * No supply was specified for this regulator and
3413                          * there will never be one.
3414                          */
3415                         ret = 0;
3416                         goto add_dev;
3417                 } else if (!r) {
3418                         dev_err(dev, "Failed to find supply %s\n", supply);
3419                         ret = -EPROBE_DEFER;
3420                         goto scrub;
3421                 }
3422
3423                 ret = set_supply(rdev, r);
3424                 if (ret < 0)
3425                         goto scrub;
3426
3427                 /* Enable supply if rail is enabled */
3428                 if (_regulator_is_enabled(rdev)) {
3429                         ret = regulator_enable(rdev->supply);
3430                         if (ret < 0)
3431                                 goto scrub;
3432                 }
3433         }
3434
3435 add_dev:
3436         /* add consumers devices */
3437         if (init_data) {
3438                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
3439                         ret = set_consumer_device_supply(rdev,
3440                                 init_data->consumer_supplies[i].dev_name,
3441                                 init_data->consumer_supplies[i].supply);
3442                         if (ret < 0) {
3443                                 dev_err(dev, "Failed to set supply %s\n",
3444                                         init_data->consumer_supplies[i].supply);
3445                                 goto unset_supplies;
3446                         }
3447                 }
3448         }
3449
3450         list_add(&rdev->list, &regulator_list);
3451
3452         rdev_init_debugfs(rdev);
3453 out:
3454         mutex_unlock(&regulator_list_mutex);
3455         return rdev;
3456
3457 unset_supplies:
3458         unset_regulator_supplies(rdev);
3459
3460 scrub:
3461         if (rdev->supply)
3462                 _regulator_put(rdev->supply);
3463         regulator_ena_gpio_free(rdev);
3464         kfree(rdev->constraints);
3465 wash:
3466         device_unregister(&rdev->dev);
3467         /* device core frees rdev */
3468         rdev = ERR_PTR(ret);
3469         goto out;
3470
3471 clean:
3472         kfree(rdev);
3473         rdev = ERR_PTR(ret);
3474         goto out;
3475 }
3476 EXPORT_SYMBOL_GPL(regulator_register);
3477
3478 /**
3479  * regulator_unregister - unregister regulator
3480  * @rdev: regulator to unregister
3481  *
3482  * Called by regulator drivers to unregister a regulator.
3483  */
3484 void regulator_unregister(struct regulator_dev *rdev)
3485 {
3486         if (rdev == NULL)
3487                 return;
3488
3489         if (rdev->supply) {
3490                 while (rdev->use_count--)
3491                         regulator_disable(rdev->supply);
3492                 regulator_put(rdev->supply);
3493         }
3494         mutex_lock(&regulator_list_mutex);
3495         debugfs_remove_recursive(rdev->debugfs);
3496         flush_work(&rdev->disable_work.work);
3497         WARN_ON(rdev->open_count);
3498         unset_regulator_supplies(rdev);
3499         list_del(&rdev->list);
3500         kfree(rdev->constraints);
3501         regulator_ena_gpio_free(rdev);
3502         device_unregister(&rdev->dev);
3503         mutex_unlock(&regulator_list_mutex);
3504 }
3505 EXPORT_SYMBOL_GPL(regulator_unregister);
3506
3507 /**
3508  * regulator_suspend_prepare - prepare regulators for system wide suspend
3509  * @state: system suspend state
3510  *
3511  * Configure each regulator with it's suspend operating parameters for state.
3512  * This will usually be called by machine suspend code prior to supending.
3513  */
3514 int regulator_suspend_prepare(suspend_state_t state)
3515 {
3516         struct regulator_dev *rdev;
3517         int ret = 0;
3518
3519         /* ON is handled by regulator active state */
3520         if (state == PM_SUSPEND_ON)
3521                 return -EINVAL;
3522
3523         mutex_lock(&regulator_list_mutex);
3524         list_for_each_entry(rdev, &regulator_list, list) {
3525
3526                 mutex_lock(&rdev->mutex);
3527                 ret = suspend_prepare(rdev, state);
3528                 mutex_unlock(&rdev->mutex);
3529
3530                 if (ret < 0) {
3531                         rdev_err(rdev, "failed to prepare\n");
3532                         goto out;
3533                 }
3534         }
3535 out:
3536         mutex_unlock(&regulator_list_mutex);
3537         return ret;
3538 }
3539 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3540
3541 /**
3542  * regulator_suspend_finish - resume regulators from system wide suspend
3543  *
3544  * Turn on regulators that might be turned off by regulator_suspend_prepare
3545  * and that should be turned on according to the regulators properties.
3546  */
3547 int regulator_suspend_finish(void)
3548 {
3549         struct regulator_dev *rdev;
3550         int ret = 0, error;
3551
3552         mutex_lock(&regulator_list_mutex);
3553         list_for_each_entry(rdev, &regulator_list, list) {
3554                 struct regulator_ops *ops = rdev->desc->ops;
3555
3556                 mutex_lock(&rdev->mutex);
3557                 if ((rdev->use_count > 0  || rdev->constraints->always_on) &&
3558                                 ops->enable) {
3559                         error = ops->enable(rdev);
3560                         if (error)
3561                                 ret = error;
3562                 } else {
3563                         if (!has_full_constraints)
3564                                 goto unlock;
3565                         if (!ops->disable)
3566                                 goto unlock;
3567                         if (!_regulator_is_enabled(rdev))
3568                                 goto unlock;
3569
3570                         error = ops->disable(rdev);
3571                         if (error)
3572                                 ret = error;
3573                 }
3574 unlock:
3575                 mutex_unlock(&rdev->mutex);
3576         }
3577         mutex_unlock(&regulator_list_mutex);
3578         return ret;
3579 }
3580 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3581
3582 /**
3583  * regulator_has_full_constraints - the system has fully specified constraints
3584  *
3585  * Calling this function will cause the regulator API to disable all
3586  * regulators which have a zero use count and don't have an always_on
3587  * constraint in a late_initcall.
3588  *
3589  * The intention is that this will become the default behaviour in a
3590  * future kernel release so users are encouraged to use this facility
3591  * now.
3592  */
3593 void regulator_has_full_constraints(void)
3594 {
3595         has_full_constraints = 1;
3596 }
3597 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3598
3599 /**
3600  * regulator_use_dummy_regulator - Provide a dummy regulator when none is found
3601  *
3602  * Calling this function will cause the regulator API to provide a
3603  * dummy regulator to consumers if no physical regulator is found,
3604  * allowing most consumers to proceed as though a regulator were
3605  * configured.  This allows systems such as those with software
3606  * controllable regulators for the CPU core only to be brought up more
3607  * readily.
3608  */
3609 void regulator_use_dummy_regulator(void)
3610 {
3611         board_wants_dummy_regulator = true;
3612 }
3613 EXPORT_SYMBOL_GPL(regulator_use_dummy_regulator);
3614
3615 /**
3616  * rdev_get_drvdata - get rdev regulator driver data
3617  * @rdev: regulator
3618  *
3619  * Get rdev regulator driver private data. This call can be used in the
3620  * regulator driver context.
3621  */
3622 void *rdev_get_drvdata(struct regulator_dev *rdev)
3623 {
3624         return rdev->reg_data;
3625 }
3626 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3627
3628 /**
3629  * regulator_get_drvdata - get regulator driver data
3630  * @regulator: regulator
3631  *
3632  * Get regulator driver private data. This call can be used in the consumer
3633  * driver context when non API regulator specific functions need to be called.
3634  */
3635 void *regulator_get_drvdata(struct regulator *regulator)
3636 {
3637         return regulator->rdev->reg_data;
3638 }
3639 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3640
3641 /**
3642  * regulator_set_drvdata - set regulator driver data
3643  * @regulator: regulator
3644  * @data: data
3645  */
3646 void regulator_set_drvdata(struct regulator *regulator, void *data)
3647 {
3648         regulator->rdev->reg_data = data;
3649 }
3650 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3651
3652 /**
3653  * regulator_get_id - get regulator ID
3654  * @rdev: regulator
3655  */
3656 int rdev_get_id(struct regulator_dev *rdev)
3657 {
3658         return rdev->desc->id;
3659 }
3660 EXPORT_SYMBOL_GPL(rdev_get_id);
3661
3662 struct device *rdev_get_dev(struct regulator_dev *rdev)
3663 {
3664         return &rdev->dev;
3665 }
3666 EXPORT_SYMBOL_GPL(rdev_get_dev);
3667
3668 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
3669 {
3670         return reg_init_data->driver_data;
3671 }
3672 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
3673
3674 #ifdef CONFIG_DEBUG_FS
3675 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
3676                                     size_t count, loff_t *ppos)
3677 {
3678         char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
3679         ssize_t len, ret = 0;
3680         struct regulator_map *map;
3681
3682         if (!buf)
3683                 return -ENOMEM;
3684
3685         list_for_each_entry(map, &regulator_map_list, list) {
3686                 len = snprintf(buf + ret, PAGE_SIZE - ret,
3687                                "%s -> %s.%s\n",
3688                                rdev_get_name(map->regulator), map->dev_name,
3689                                map->supply);
3690                 if (len >= 0)
3691                         ret += len;
3692                 if (ret > PAGE_SIZE) {
3693                         ret = PAGE_SIZE;
3694                         break;
3695                 }
3696         }
3697
3698         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
3699
3700         kfree(buf);
3701
3702         return ret;
3703 }
3704 #endif
3705
3706 static const struct file_operations supply_map_fops = {
3707 #ifdef CONFIG_DEBUG_FS
3708         .read = supply_map_read_file,
3709         .llseek = default_llseek,
3710 #endif
3711 };
3712
3713 static int __init regulator_init(void)
3714 {
3715         int ret;
3716
3717         ret = class_register(&regulator_class);
3718
3719         debugfs_root = debugfs_create_dir("regulator", NULL);
3720         if (!debugfs_root)
3721                 pr_warn("regulator: Failed to create debugfs directory\n");
3722
3723         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
3724                             &supply_map_fops);
3725
3726         regulator_dummy_init();
3727
3728         return ret;
3729 }
3730
3731 /* init early to allow our consumers to complete system booting */
3732 core_initcall(regulator_init);
3733
3734 static int __init regulator_init_complete(void)
3735 {
3736         struct regulator_dev *rdev;
3737         struct regulator_ops *ops;
3738         struct regulation_constraints *c;
3739         int enabled, ret;
3740
3741         /*
3742          * Since DT doesn't provide an idiomatic mechanism for
3743          * enabling full constraints and since it's much more natural
3744          * with DT to provide them just assume that a DT enabled
3745          * system has full constraints.
3746          */
3747         if (of_have_populated_dt())
3748                 has_full_constraints = true;
3749
3750         mutex_lock(&regulator_list_mutex);
3751
3752         /* If we have a full configuration then disable any regulators
3753          * which are not in use or always_on.  This will become the
3754          * default behaviour in the future.
3755          */
3756         list_for_each_entry(rdev, &regulator_list, list) {
3757                 ops = rdev->desc->ops;
3758                 c = rdev->constraints;
3759
3760                 if (!ops->disable || (c && c->always_on))
3761                         continue;
3762
3763                 mutex_lock(&rdev->mutex);
3764
3765                 if (rdev->use_count)
3766                         goto unlock;
3767
3768                 /* If we can't read the status assume it's on. */
3769                 if (ops->is_enabled)
3770                         enabled = ops->is_enabled(rdev);
3771                 else
3772                         enabled = 1;
3773
3774                 if (!enabled)
3775                         goto unlock;
3776
3777                 if (has_full_constraints) {
3778                         /* We log since this may kill the system if it
3779                          * goes wrong. */
3780                         rdev_info(rdev, "disabling\n");
3781                         ret = ops->disable(rdev);
3782                         if (ret != 0) {
3783                                 rdev_err(rdev, "couldn't disable: %d\n", ret);
3784                         }
3785                 } else {
3786                         /* The intention is that in future we will
3787                          * assume that full constraints are provided
3788                          * so warn even if we aren't going to do
3789                          * anything here.
3790                          */
3791                         rdev_warn(rdev, "incomplete constraints, leaving on\n");
3792                 }
3793
3794 unlock:
3795                 mutex_unlock(&rdev->mutex);
3796         }
3797
3798         mutex_unlock(&regulator_list_mutex);
3799
3800         return 0;
3801 }
3802 late_initcall(regulator_init_complete);