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/gpio/consumer.h>
  28 #include <linux/of.h>
  29 #include <linux/regmap.h>
  30 #include <linux/regulator/of_regulator.h>
  31 #include <linux/regulator/consumer.h>
  32 #include <linux/regulator/driver.h>
  33 #include <linux/regulator/machine.h>
  34 #include <linux/module.h>
  35
  36 #define CREATE_TRACE_POINTS
  37 #include <trace/events/regulator.h>
  38
  39 #include "dummy.h"
  40 #include "internal.h"
  41
  42 #define rdev_crit(rdev, fmt, ...)                                       \
  43         pr_crit("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  44 #define rdev_err(rdev, fmt, ...)                                        \
  45         pr_err("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  46 #define rdev_warn(rdev, fmt, ...)                                       \
  47         pr_warn("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  48 #define rdev_info(rdev, fmt, ...)                                       \
  49         pr_info("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  50 #define rdev_dbg(rdev, fmt, ...)                                        \
  51         pr_debug("%s: " fmt, rdev_get_name(rdev), ##__VA_ARGS__)
  52
  53 static DEFINE_MUTEX(regulator_list_mutex);
  54 static LIST_HEAD(regulator_list);
  55 static LIST_HEAD(regulator_map_list);
  56 static LIST_HEAD(regulator_ena_gpio_list);
  57 static LIST_HEAD(regulator_supply_alias_list);
  58 static bool has_full_constraints;
  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         struct gpio_desc *gpiod;
  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 int _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 static bool have_full_constraints(void)
 124 {
 125         return has_full_constraints || of_have_populated_dt();
 126 }
 127
 128 /**
 129  * of_get_regulator - get a regulator device node based on supply name
 130  * @dev: Device pointer for the consumer (of regulator) device
 131  * @supply: regulator supply name
 132  *
 133  * Extract the regulator device node corresponding to the supply name.
 134  * returns the device node corresponding to the regulator if found, else
 135  * returns NULL.
 136  */
 137 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 138 {
 139         struct device_node *regnode = NULL;
 140         char prop_name[32]; /* 32 is max size of property name */
 141
 142         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 143
 144         snprintf(prop_name, 32, "%s-supply", supply);
 145         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 146
 147         if (!regnode) {
 148                 dev_dbg(dev, "Looking up %s property in node %s failed",
 149                                 prop_name, dev->of_node->full_name);
 150                 return NULL;
 151         }
 152         return regnode;
 153 }
 154
 155 static int _regulator_can_change_status(struct regulator_dev *rdev)
 156 {
 157         if (!rdev->constraints)
 158                 return 0;
 159
 160         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
 161                 return 1;
 162         else
 163                 return 0;
 164 }
 165
 166 /* Platform voltage constraint check */
 167 static int regulator_check_voltage(struct regulator_dev *rdev,
 168                                    int *min_uV, int *max_uV)
 169 {
 170         BUG_ON(*min_uV > *max_uV);
 171
 172         if (!rdev->constraints) {
 173                 rdev_err(rdev, "no constraints\n");
 174                 return -ENODEV;
 175         }
 176         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 177                 rdev_err(rdev, "operation not allowed\n");
 178                 return -EPERM;
 179         }
 180
 181         if (*max_uV > rdev->constraints->max_uV)
 182                 *max_uV = rdev->constraints->max_uV;
 183         if (*min_uV < rdev->constraints->min_uV)
 184                 *min_uV = rdev->constraints->min_uV;
 185
 186         if (*min_uV > *max_uV) {
 187                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 188                          *min_uV, *max_uV);
 189                 return -EINVAL;
 190         }
 191
 192         return 0;
 193 }
 194
 195 /* Make sure we select a voltage that suits the needs of all
 196  * regulator consumers
 197  */
 198 static int regulator_check_consumers(struct regulator_dev *rdev,
 199                                      int *min_uV, int *max_uV)
 200 {
 201         struct regulator *regulator;
 202
 203         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 204                 /*
 205                  * Assume consumers that didn't say anything are OK
 206                  * with anything in the constraint range.
 207                  */
 208                 if (!regulator->min_uV && !regulator->max_uV)
 209                         continue;
 210
 211                 if (*max_uV > regulator->max_uV)
 212                         *max_uV = regulator->max_uV;
 213                 if (*min_uV < regulator->min_uV)
 214                         *min_uV = regulator->min_uV;
 215         }
 216
 217         if (*min_uV > *max_uV) {
 218                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
 219                         *min_uV, *max_uV);
 220                 return -EINVAL;
 221         }
 222
 223         return 0;
 224 }
 225
 226 /* current constraint check */
 227 static int regulator_check_current_limit(struct regulator_dev *rdev,
 228                                         int *min_uA, int *max_uA)
 229 {
 230         BUG_ON(*min_uA > *max_uA);
 231
 232         if (!rdev->constraints) {
 233                 rdev_err(rdev, "no constraints\n");
 234                 return -ENODEV;
 235         }
 236         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 237                 rdev_err(rdev, "operation not allowed\n");
 238                 return -EPERM;
 239         }
 240
 241         if (*max_uA > rdev->constraints->max_uA)
 242                 *max_uA = rdev->constraints->max_uA;
 243         if (*min_uA < rdev->constraints->min_uA)
 244                 *min_uA = rdev->constraints->min_uA;
 245
 246         if (*min_uA > *max_uA) {
 247                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 248                          *min_uA, *max_uA);
 249                 return -EINVAL;
 250         }
 251
 252         return 0;
 253 }
 254
 255 /* operating mode constraint check */
 256 static int regulator_mode_constrain(struct regulator_dev *rdev, int *mode)
 257 {
 258         switch (*mode) {
 259         case REGULATOR_MODE_FAST:
 260         case REGULATOR_MODE_NORMAL:
 261         case REGULATOR_MODE_IDLE:
 262         case REGULATOR_MODE_STANDBY:
 263                 break;
 264         default:
 265                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 266                 return -EINVAL;
 267         }
 268
 269         if (!rdev->constraints) {
 270                 rdev_err(rdev, "no constraints\n");
 271                 return -ENODEV;
 272         }
 273         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 274                 rdev_err(rdev, "operation not allowed\n");
 275                 return -EPERM;
 276         }
 277
 278         /* The modes are bitmasks, the most power hungry modes having
 279          * the lowest values. If the requested mode isn't supported
 280          * try higher modes. */
 281         while (*mode) {
 282                 if (rdev->constraints->valid_modes_mask & *mode)
 283                         return 0;
 284                 *mode /= 2;
 285         }
 286
 287         return -EINVAL;
 288 }
 289
 290 /* dynamic regulator mode switching constraint check */
 291 static int regulator_check_drms(struct regulator_dev *rdev)
 292 {
 293         if (!rdev->constraints) {
 294                 rdev_err(rdev, "no constraints\n");
 295                 return -ENODEV;
 296         }
 297         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 298                 rdev_err(rdev, "operation not allowed\n");
 299                 return -EPERM;
 300         }
 301         return 0;
 302 }
 303
 304 static ssize_t regulator_uV_show(struct device *dev,
 305                                 struct device_attribute *attr, char *buf)
 306 {
 307         struct regulator_dev *rdev = dev_get_drvdata(dev);
 308         ssize_t ret;
 309
 310         mutex_lock(&rdev->mutex);
 311         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 312         mutex_unlock(&rdev->mutex);
 313
 314         return ret;
 315 }
 316 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 317
 318 static ssize_t regulator_uA_show(struct device *dev,
 319                                 struct device_attribute *attr, char *buf)
 320 {
 321         struct regulator_dev *rdev = dev_get_drvdata(dev);
 322
 323         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 324 }
 325 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 326
 327 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 328                          char *buf)
 329 {
 330         struct regulator_dev *rdev = dev_get_drvdata(dev);
 331
 332         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 333 }
 334 static DEVICE_ATTR_RO(name);
 335
 336 static ssize_t regulator_print_opmode(char *buf, int mode)
 337 {
 338         switch (mode) {
 339         case REGULATOR_MODE_FAST:
 340                 return sprintf(buf, "fast\n");
 341         case REGULATOR_MODE_NORMAL:
 342                 return sprintf(buf, "normal\n");
 343         case REGULATOR_MODE_IDLE:
 344                 return sprintf(buf, "idle\n");
 345         case REGULATOR_MODE_STANDBY:
 346                 return sprintf(buf, "standby\n");
 347         }
 348         return sprintf(buf, "unknown\n");
 349 }
 350
 351 static ssize_t regulator_opmode_show(struct device *dev,
 352                                     struct device_attribute *attr, char *buf)
 353 {
 354         struct regulator_dev *rdev = dev_get_drvdata(dev);
 355
 356         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 357 }
 358 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 359
 360 static ssize_t regulator_print_state(char *buf, int state)
 361 {
 362         if (state > 0)
 363                 return sprintf(buf, "enabled\n");
 364         else if (state == 0)
 365                 return sprintf(buf, "disabled\n");
 366         else
 367                 return sprintf(buf, "unknown\n");
 368 }
 369
 370 static ssize_t regulator_state_show(struct device *dev,
 371                                    struct device_attribute *attr, char *buf)
 372 {
 373         struct regulator_dev *rdev = dev_get_drvdata(dev);
 374         ssize_t ret;
 375
 376         mutex_lock(&rdev->mutex);
 377         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 378         mutex_unlock(&rdev->mutex);
 379
 380         return ret;
 381 }
 382 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 383
 384 static ssize_t regulator_status_show(struct device *dev,
 385                                    struct device_attribute *attr, char *buf)
 386 {
 387         struct regulator_dev *rdev = dev_get_drvdata(dev);
 388         int status;
 389         char *label;
 390
 391         status = rdev->desc->ops->get_status(rdev);
 392         if (status < 0)
 393                 return status;
 394
 395         switch (status) {
 396         case REGULATOR_STATUS_OFF:
 397                 label = "off";
 398                 break;
 399         case REGULATOR_STATUS_ON:
 400                 label = "on";
 401                 break;
 402         case REGULATOR_STATUS_ERROR:
 403                 label = "error";
 404                 break;
 405         case REGULATOR_STATUS_FAST:
 406                 label = "fast";
 407                 break;
 408         case REGULATOR_STATUS_NORMAL:
 409                 label = "normal";
 410                 break;
 411         case REGULATOR_STATUS_IDLE:
 412                 label = "idle";
 413                 break;
 414         case REGULATOR_STATUS_STANDBY:
 415                 label = "standby";
 416                 break;
 417         case REGULATOR_STATUS_BYPASS:
 418                 label = "bypass";
 419                 break;
 420         case REGULATOR_STATUS_UNDEFINED:
 421                 label = "undefined";
 422                 break;
 423         default:
 424                 return -ERANGE;
 425         }
 426
 427         return sprintf(buf, "%s\n", label);
 428 }
 429 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 430
 431 static ssize_t regulator_min_uA_show(struct device *dev,
 432                                     struct device_attribute *attr, char *buf)
 433 {
 434         struct regulator_dev *rdev = dev_get_drvdata(dev);
 435
 436         if (!rdev->constraints)
 437                 return sprintf(buf, "constraint not defined\n");
 438
 439         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 440 }
 441 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 442
 443 static ssize_t regulator_max_uA_show(struct device *dev,
 444                                     struct device_attribute *attr, char *buf)
 445 {
 446         struct regulator_dev *rdev = dev_get_drvdata(dev);
 447
 448         if (!rdev->constraints)
 449                 return sprintf(buf, "constraint not defined\n");
 450
 451         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 452 }
 453 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 454
 455 static ssize_t regulator_min_uV_show(struct device *dev,
 456                                     struct device_attribute *attr, char *buf)
 457 {
 458         struct regulator_dev *rdev = dev_get_drvdata(dev);
 459
 460         if (!rdev->constraints)
 461                 return sprintf(buf, "constraint not defined\n");
 462
 463         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 464 }
 465 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 466
 467 static ssize_t regulator_max_uV_show(struct device *dev,
 468                                     struct device_attribute *attr, char *buf)
 469 {
 470         struct regulator_dev *rdev = dev_get_drvdata(dev);
 471
 472         if (!rdev->constraints)
 473                 return sprintf(buf, "constraint not defined\n");
 474
 475         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 476 }
 477 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 478
 479 static ssize_t regulator_total_uA_show(struct device *dev,
 480                                       struct device_attribute *attr, char *buf)
 481 {
 482         struct regulator_dev *rdev = dev_get_drvdata(dev);
 483         struct regulator *regulator;
 484         int uA = 0;
 485
 486         mutex_lock(&rdev->mutex);
 487         list_for_each_entry(regulator, &rdev->consumer_list, list)
 488                 uA += regulator->uA_load;
 489         mutex_unlock(&rdev->mutex);
 490         return sprintf(buf, "%d\n", uA);
 491 }
 492 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 493
 494 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
 495                               char *buf)
 496 {
 497         struct regulator_dev *rdev = dev_get_drvdata(dev);
 498         return sprintf(buf, "%d\n", rdev->use_count);
 499 }
 500 static DEVICE_ATTR_RO(num_users);
 501
 502 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 503                          char *buf)
 504 {
 505         struct regulator_dev *rdev = dev_get_drvdata(dev);
 506
 507         switch (rdev->desc->type) {
 508         case REGULATOR_VOLTAGE:
 509                 return sprintf(buf, "voltage\n");
 510         case REGULATOR_CURRENT:
 511                 return sprintf(buf, "current\n");
 512         }
 513         return sprintf(buf, "unknown\n");
 514 }
 515 static DEVICE_ATTR_RO(type);
 516
 517 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 518                                 struct device_attribute *attr, char *buf)
 519 {
 520         struct regulator_dev *rdev = dev_get_drvdata(dev);
 521
 522         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 523 }
 524 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 525                 regulator_suspend_mem_uV_show, NULL);
 526
 527 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 528                                 struct device_attribute *attr, char *buf)
 529 {
 530         struct regulator_dev *rdev = dev_get_drvdata(dev);
 531
 532         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 533 }
 534 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 535                 regulator_suspend_disk_uV_show, NULL);
 536
 537 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 538                                 struct device_attribute *attr, char *buf)
 539 {
 540         struct regulator_dev *rdev = dev_get_drvdata(dev);
 541
 542         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 543 }
 544 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 545                 regulator_suspend_standby_uV_show, NULL);
 546
 547 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 548                                 struct device_attribute *attr, char *buf)
 549 {
 550         struct regulator_dev *rdev = dev_get_drvdata(dev);
 551
 552         return regulator_print_opmode(buf,
 553                 rdev->constraints->state_mem.mode);
 554 }
 555 static DEVICE_ATTR(suspend_mem_mode, 0444,
 556                 regulator_suspend_mem_mode_show, NULL);
 557
 558 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 559                                 struct device_attribute *attr, char *buf)
 560 {
 561         struct regulator_dev *rdev = dev_get_drvdata(dev);
 562
 563         return regulator_print_opmode(buf,
 564                 rdev->constraints->state_disk.mode);
 565 }
 566 static DEVICE_ATTR(suspend_disk_mode, 0444,
 567                 regulator_suspend_disk_mode_show, NULL);
 568
 569 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 570                                 struct device_attribute *attr, char *buf)
 571 {
 572         struct regulator_dev *rdev = dev_get_drvdata(dev);
 573
 574         return regulator_print_opmode(buf,
 575                 rdev->constraints->state_standby.mode);
 576 }
 577 static DEVICE_ATTR(suspend_standby_mode, 0444,
 578                 regulator_suspend_standby_mode_show, NULL);
 579
 580 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 581                                    struct device_attribute *attr, char *buf)
 582 {
 583         struct regulator_dev *rdev = dev_get_drvdata(dev);
 584
 585         return regulator_print_state(buf,
 586                         rdev->constraints->state_mem.enabled);
 587 }
 588 static DEVICE_ATTR(suspend_mem_state, 0444,
 589                 regulator_suspend_mem_state_show, NULL);
 590
 591 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 592                                    struct device_attribute *attr, char *buf)
 593 {
 594         struct regulator_dev *rdev = dev_get_drvdata(dev);
 595
 596         return regulator_print_state(buf,
 597                         rdev->constraints->state_disk.enabled);
 598 }
 599 static DEVICE_ATTR(suspend_disk_state, 0444,
 600                 regulator_suspend_disk_state_show, NULL);
 601
 602 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 603                                    struct device_attribute *attr, char *buf)
 604 {
 605         struct regulator_dev *rdev = dev_get_drvdata(dev);
 606
 607         return regulator_print_state(buf,
 608                         rdev->constraints->state_standby.enabled);
 609 }
 610 static DEVICE_ATTR(suspend_standby_state, 0444,
 611                 regulator_suspend_standby_state_show, NULL);
 612
 613 static ssize_t regulator_bypass_show(struct device *dev,
 614                                      struct device_attribute *attr, char *buf)
 615 {
 616         struct regulator_dev *rdev = dev_get_drvdata(dev);
 617         const char *report;
 618         bool bypass;
 619         int ret;
 620
 621         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
 622
 623         if (ret != 0)
 624                 report = "unknown";
 625         else if (bypass)
 626                 report = "enabled";
 627         else
 628                 report = "disabled";
 629
 630         return sprintf(buf, "%s\n", report);
 631 }
 632 static DEVICE_ATTR(bypass, 0444,
 633                    regulator_bypass_show, NULL);
 634
 635 /* Calculate the new optimum regulator operating mode based on the new total
 636  * consumer load. All locks held by caller */
 637 static int drms_uA_update(struct regulator_dev *rdev)
 638 {
 639         struct regulator *sibling;
 640         int current_uA = 0, output_uV, input_uV, err;
 641         unsigned int mode;
 642
 643         /*
 644          * first check to see if we can set modes at all, otherwise just
 645          * tell the consumer everything is OK.
 646          */
 647         err = regulator_check_drms(rdev);
 648         if (err < 0)
 649                 return 0;
 650
 651         if (!rdev->desc->ops->get_optimum_mode)
 652                 return 0;
 653
 654         if (!rdev->desc->ops->set_mode)
 655                 return -EINVAL;
 656
 657         /* get output voltage */
 658         output_uV = _regulator_get_voltage(rdev);
 659         if (output_uV <= 0) {
 660                 rdev_err(rdev, "invalid output voltage found\n");
 661                 return -EINVAL;
 662         }
 663
 664         /* get input voltage */
 665         input_uV = 0;
 666         if (rdev->supply)
 667                 input_uV = regulator_get_voltage(rdev->supply);
 668         if (input_uV <= 0)
 669                 input_uV = rdev->constraints->input_uV;
 670         if (input_uV <= 0) {
 671                 rdev_err(rdev, "invalid input voltage found\n");
 672                 return -EINVAL;
 673         }
 674
 675         /* calc total requested load */
 676         list_for_each_entry(sibling, &rdev->consumer_list, list)
 677                 current_uA += sibling->uA_load;
 678
 679         /* now get the optimum mode for our new total regulator load */
 680         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 681                                                   output_uV, current_uA);
 682
 683         /* check the new mode is allowed */
 684         err = regulator_mode_constrain(rdev, &mode);
 685         if (err < 0) {
 686                 rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV\n",
 687                          current_uA, input_uV, output_uV);
 688                 return err;
 689         }
 690
 691         err = rdev->desc->ops->set_mode(rdev, mode);
 692         if (err < 0)
 693                 rdev_err(rdev, "failed to set optimum mode %x\n", mode);
 694
 695         return err;
 696 }
 697
 698 static int suspend_set_state(struct regulator_dev *rdev,
 699         struct regulator_state *rstate)
 700 {
 701         int ret = 0;
 702
 703         /* If we have no suspend mode configration don't set anything;
 704          * only warn if the driver implements set_suspend_voltage or
 705          * set_suspend_mode callback.
 706          */
 707         if (!rstate->enabled && !rstate->disabled) {
 708                 if (rdev->desc->ops->set_suspend_voltage ||
 709                     rdev->desc->ops->set_suspend_mode)
 710                         rdev_warn(rdev, "No configuration\n");
 711                 return 0;
 712         }
 713
 714         if (rstate->enabled && rstate->disabled) {
 715                 rdev_err(rdev, "invalid configuration\n");
 716                 return -EINVAL;
 717         }
 718
 719         if (rstate->enabled && rdev->desc->ops->set_suspend_enable)
 720                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 721         else if (rstate->disabled && rdev->desc->ops->set_suspend_disable)
 722                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 723         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
 724                 ret = 0;
 725
 726         if (ret < 0) {
 727                 rdev_err(rdev, "failed to enabled/disable\n");
 728                 return ret;
 729         }
 730
 731         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 732                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 733                 if (ret < 0) {
 734                         rdev_err(rdev, "failed to set voltage\n");
 735                         return ret;
 736                 }
 737         }
 738
 739         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 740                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 741                 if (ret < 0) {
 742                         rdev_err(rdev, "failed to set mode\n");
 743                         return ret;
 744                 }
 745         }
 746         return ret;
 747 }
 748
 749 /* locks held by caller */
 750 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 751 {
 752         if (!rdev->constraints)
 753                 return -EINVAL;
 754
 755         switch (state) {
 756         case PM_SUSPEND_STANDBY:
 757                 return suspend_set_state(rdev,
 758                         &rdev->constraints->state_standby);
 759         case PM_SUSPEND_MEM:
 760                 return suspend_set_state(rdev,
 761                         &rdev->constraints->state_mem);
 762         case PM_SUSPEND_MAX:
 763                 return suspend_set_state(rdev,
 764                         &rdev->constraints->state_disk);
 765         default:
 766                 return -EINVAL;
 767         }
 768 }
 769
 770 static void print_constraints(struct regulator_dev *rdev)
 771 {
 772         struct regulation_constraints *constraints = rdev->constraints;
 773         char buf[80] = "";
 774         int count = 0;
 775         int ret;
 776
 777         if (constraints->min_uV && constraints->max_uV) {
 778                 if (constraints->min_uV == constraints->max_uV)
 779                         count += sprintf(buf + count, "%d mV ",
 780                                          constraints->min_uV / 1000);
 781                 else
 782                         count += sprintf(buf + count, "%d <--> %d mV ",
 783                                          constraints->min_uV / 1000,
 784                                          constraints->max_uV / 1000);
 785         }
 786
 787         if (!constraints->min_uV ||
 788             constraints->min_uV != constraints->max_uV) {
 789                 ret = _regulator_get_voltage(rdev);
 790                 if (ret > 0)
 791                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 792         }
 793
 794         if (constraints->uV_offset)
 795                 count += sprintf(buf, "%dmV offset ",
 796                                  constraints->uV_offset / 1000);
 797
 798         if (constraints->min_uA && constraints->max_uA) {
 799                 if (constraints->min_uA == constraints->max_uA)
 800                         count += sprintf(buf + count, "%d mA ",
 801                                          constraints->min_uA / 1000);
 802                 else
 803                         count += sprintf(buf + count, "%d <--> %d mA ",
 804                                          constraints->min_uA / 1000,
 805                                          constraints->max_uA / 1000);
 806         }
 807
 808         if (!constraints->min_uA ||
 809             constraints->min_uA != constraints->max_uA) {
 810                 ret = _regulator_get_current_limit(rdev);
 811                 if (ret > 0)
 812                         count += sprintf(buf + count, "at %d mA ", ret / 1000);
 813         }
 814
 815         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 816                 count += sprintf(buf + count, "fast ");
 817         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 818                 count += sprintf(buf + count, "normal ");
 819         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 820                 count += sprintf(buf + count, "idle ");
 821         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 822                 count += sprintf(buf + count, "standby");
 823
 824         if (!count)
 825                 sprintf(buf, "no parameters");
 826
 827         rdev_dbg(rdev, "%s\n", buf);
 828
 829         if ((constraints->min_uV != constraints->max_uV) &&
 830             !(constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE))
 831                 rdev_warn(rdev,
 832                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
 833 }
 834
 835 static int machine_constraints_voltage(struct regulator_dev *rdev,
 836         struct regulation_constraints *constraints)
 837 {
 838         const struct regulator_ops *ops = rdev->desc->ops;
 839         int ret;
 840
 841         /* do we need to apply the constraint voltage */
 842         if (rdev->constraints->apply_uV &&
 843             rdev->constraints->min_uV == rdev->constraints->max_uV) {
 844                 int current_uV = _regulator_get_voltage(rdev);
 845                 if (current_uV < 0) {
 846                         rdev_err(rdev,
 847                                  "failed to get the current voltage(%d)\n",
 848                                  current_uV);
 849                         return current_uV;
 850                 }
 851                 if (current_uV < rdev->constraints->min_uV ||
 852                     current_uV > rdev->constraints->max_uV) {
 853                         ret = _regulator_do_set_voltage(
 854                                 rdev, rdev->constraints->min_uV,
 855                                 rdev->constraints->max_uV);
 856                         if (ret < 0) {
 857                                 rdev_err(rdev,
 858                                         "failed to apply %duV constraint(%d)\n",
 859                                         rdev->constraints->min_uV, ret);
 860                                 return ret;
 861                         }
 862                 }
 863         }
 864
 865         /* constrain machine-level voltage specs to fit
 866          * the actual range supported by this regulator.
 867          */
 868         if (ops->list_voltage && rdev->desc->n_voltages) {
 869                 int     count = rdev->desc->n_voltages;
 870                 int     i;
 871                 int     min_uV = INT_MAX;
 872                 int     max_uV = INT_MIN;
 873                 int     cmin = constraints->min_uV;
 874                 int     cmax = constraints->max_uV;
 875
 876                 /* it's safe to autoconfigure fixed-voltage supplies
 877                    and the constraints are used by list_voltage. */
 878                 if (count == 1 && !cmin) {
 879                         cmin = 1;
 880                         cmax = INT_MAX;
 881                         constraints->min_uV = cmin;
 882                         constraints->max_uV = cmax;
 883                 }
 884
 885                 /* voltage constraints are optional */
 886                 if ((cmin == 0) && (cmax == 0))
 887                         return 0;
 888
 889                 /* else require explicit machine-level constraints */
 890                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 891                         rdev_err(rdev, "invalid voltage constraints\n");
 892                         return -EINVAL;
 893                 }
 894
 895                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 896                 for (i = 0; i < count; i++) {
 897                         int     value;
 898
 899                         value = ops->list_voltage(rdev, i);
 900                         if (value <= 0)
 901                                 continue;
 902
 903                         /* maybe adjust [min_uV..max_uV] */
 904                         if (value >= cmin && value < min_uV)
 905                                 min_uV = value;
 906                         if (value <= cmax && value > max_uV)
 907                                 max_uV = value;
 908                 }
 909
 910                 /* final: [min_uV..max_uV] valid iff constraints valid */
 911                 if (max_uV < min_uV) {
 912                         rdev_err(rdev,
 913                                  "unsupportable voltage constraints %u-%uuV\n",
 914                                  min_uV, max_uV);
 915                         return -EINVAL;
 916                 }
 917
 918                 /* use regulator's subset of machine constraints */
 919                 if (constraints->min_uV < min_uV) {
 920                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
 921                                  constraints->min_uV, min_uV);
 922                         constraints->min_uV = min_uV;
 923                 }
 924                 if (constraints->max_uV > max_uV) {
 925                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
 926                                  constraints->max_uV, max_uV);
 927                         constraints->max_uV = max_uV;
 928                 }
 929         }
 930
 931         return 0;
 932 }
 933
 934 static int machine_constraints_current(struct regulator_dev *rdev,
 935         struct regulation_constraints *constraints)
 936 {
 937         const struct regulator_ops *ops = rdev->desc->ops;
 938         int ret;
 939
 940         if (!constraints->min_uA && !constraints->max_uA)
 941                 return 0;
 942
 943         if (constraints->min_uA > constraints->max_uA) {
 944                 rdev_err(rdev, "Invalid current constraints\n");
 945                 return -EINVAL;
 946         }
 947
 948         if (!ops->set_current_limit || !ops->get_current_limit) {
 949                 rdev_warn(rdev, "Operation of current configuration missing\n");
 950                 return 0;
 951         }
 952
 953         /* Set regulator current in constraints range */
 954         ret = ops->set_current_limit(rdev, constraints->min_uA,
 955                         constraints->max_uA);
 956         if (ret < 0) {
 957                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
 958                 return ret;
 959         }
 960
 961         return 0;
 962 }
 963
 964 static int _regulator_do_enable(struct regulator_dev *rdev);
 965
 966 /**
 967  * set_machine_constraints - sets regulator constraints
 968  * @rdev: regulator source
 969  * @constraints: constraints to apply
 970  *
 971  * Allows platform initialisation code to define and constrain
 972  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 973  * Constraints *must* be set by platform code in order for some
 974  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 975  * set_mode.
 976  */
 977 static int set_machine_constraints(struct regulator_dev *rdev,
 978         const struct regulation_constraints *constraints)
 979 {
 980         int ret = 0;
 981         const struct regulator_ops *ops = rdev->desc->ops;
 982
 983         if (constraints)
 984                 rdev->constraints = kmemdup(constraints, sizeof(*constraints),
 985                                             GFP_KERNEL);
 986         else
 987                 rdev->constraints = kzalloc(sizeof(*constraints),
 988                                             GFP_KERNEL);
 989         if (!rdev->constraints)
 990                 return -ENOMEM;
 991
 992         ret = machine_constraints_voltage(rdev, rdev->constraints);
 993         if (ret != 0)
 994                 goto out;
 995
 996         ret = machine_constraints_current(rdev, rdev->constraints);
 997         if (ret != 0)
 998                 goto out;
 999
1000         /* do we need to setup our suspend state */
1001         if (rdev->constraints->initial_state) {
1002                 ret = suspend_prepare(rdev, rdev->constraints->initial_state);
1003                 if (ret < 0) {
1004                         rdev_err(rdev, "failed to set suspend state\n");
1005                         goto out;
1006                 }
1007         }
1008
1009         if (rdev->constraints->initial_mode) {
1010                 if (!ops->set_mode) {
1011                         rdev_err(rdev, "no set_mode operation\n");
1012                         ret = -EINVAL;
1013                         goto out;
1014                 }
1015
1016                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1017                 if (ret < 0) {
1018                         rdev_err(rdev, "failed to set initial mode: %d\n", ret);
1019                         goto out;
1020                 }
1021         }
1022
1023         /* If the constraints say the regulator should be on at this point
1024          * and we have control then make sure it is enabled.
1025          */
1026         if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1027                 ret = _regulator_do_enable(rdev);
1028                 if (ret < 0 && ret != -EINVAL) {
1029                         rdev_err(rdev, "failed to enable\n");
1030                         goto out;
1031                 }
1032         }
1033
1034         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1035                 && ops->set_ramp_delay) {
1036                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1037                 if (ret < 0) {
1038                         rdev_err(rdev, "failed to set ramp_delay\n");
1039                         goto out;
1040                 }
1041         }
1042
1043         print_constraints(rdev);
1044         return 0;
1045 out:
1046         kfree(rdev->constraints);
1047         rdev->constraints = NULL;
1048         return ret;
1049 }
1050
1051 /**
1052  * set_supply - set regulator supply regulator
1053  * @rdev: regulator name
1054  * @supply_rdev: supply regulator name
1055  *
1056  * Called by platform initialisation code to set the supply regulator for this
1057  * regulator. This ensures that a regulators supply will also be enabled by the
1058  * core if it's child is enabled.
1059  */
1060 static int set_supply(struct regulator_dev *rdev,
1061                       struct regulator_dev *supply_rdev)
1062 {
1063         int err;
1064
1065         rdev_info(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1066
1067         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1068         if (rdev->supply == NULL) {
1069                 err = -ENOMEM;
1070                 return err;
1071         }
1072         supply_rdev->open_count++;
1073
1074         return 0;
1075 }
1076
1077 /**
1078  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1079  * @rdev:         regulator source
1080  * @consumer_dev_name: dev_name() string for device supply applies to
1081  * @supply:       symbolic name for supply
1082  *
1083  * Allows platform initialisation code to map physical regulator
1084  * sources to symbolic names for supplies for use by devices.  Devices
1085  * should use these symbolic names to request regulators, avoiding the
1086  * need to provide board-specific regulator names as platform data.
1087  */
1088 static int set_consumer_device_supply(struct regulator_dev *rdev,
1089                                       const char *consumer_dev_name,
1090                                       const char *supply)
1091 {
1092         struct regulator_map *node;
1093         int has_dev;
1094
1095         if (supply == NULL)
1096                 return -EINVAL;
1097
1098         if (consumer_dev_name != NULL)
1099                 has_dev = 1;
1100         else
1101                 has_dev = 0;
1102
1103         list_for_each_entry(node, &regulator_map_list, list) {
1104                 if (node->dev_name && consumer_dev_name) {
1105                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1106                                 continue;
1107                 } else if (node->dev_name || consumer_dev_name) {
1108                         continue;
1109                 }
1110
1111                 if (strcmp(node->supply, supply) != 0)
1112                         continue;
1113
1114                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1115                          consumer_dev_name,
1116                          dev_name(&node->regulator->dev),
1117                          node->regulator->desc->name,
1118                          supply,
1119                          dev_name(&rdev->dev), rdev_get_name(rdev));
1120                 return -EBUSY;
1121         }
1122
1123         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1124         if (node == NULL)
1125                 return -ENOMEM;
1126
1127         node->regulator = rdev;
1128         node->supply = supply;
1129
1130         if (has_dev) {
1131                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1132                 if (node->dev_name == NULL) {
1133                         kfree(node);
1134                         return -ENOMEM;
1135                 }
1136         }
1137
1138         list_add(&node->list, &regulator_map_list);
1139         return 0;
1140 }
1141
1142 static void unset_regulator_supplies(struct regulator_dev *rdev)
1143 {
1144         struct regulator_map *node, *n;
1145
1146         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1147                 if (rdev == node->regulator) {
1148                         list_del(&node->list);
1149                         kfree(node->dev_name);
1150                         kfree(node);
1151                 }
1152         }
1153 }
1154
1155 #define REG_STR_SIZE    64
1156
1157 static struct regulator *create_regulator(struct regulator_dev *rdev,
1158                                           struct device *dev,
1159                                           const char *supply_name)
1160 {
1161         struct regulator *regulator;
1162         char buf[REG_STR_SIZE];
1163         int err, size;
1164
1165         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1166         if (regulator == NULL)
1167                 return NULL;
1168
1169         mutex_lock(&rdev->mutex);
1170         regulator->rdev = rdev;
1171         list_add(&regulator->list, &rdev->consumer_list);
1172
1173         if (dev) {
1174                 regulator->dev = dev;
1175
1176                 /* Add a link to the device sysfs entry */
1177                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1178                                  dev->kobj.name, supply_name);
1179                 if (size >= REG_STR_SIZE)
1180                         goto overflow_err;
1181
1182                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1183                 if (regulator->supply_name == NULL)
1184                         goto overflow_err;
1185
1186                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1187                                         buf);
1188                 if (err) {
1189                         rdev_warn(rdev, "could not add device link %s err %d\n",
1190                                   dev->kobj.name, err);
1191                         /* non-fatal */
1192                 }
1193         } else {
1194                 regulator->supply_name = kstrdup(supply_name, GFP_KERNEL);
1195                 if (regulator->supply_name == NULL)
1196                         goto overflow_err;
1197         }
1198
1199         regulator->debugfs = debugfs_create_dir(regulator->supply_name,
1200                                                 rdev->debugfs);
1201         if (!regulator->debugfs) {
1202                 rdev_warn(rdev, "Failed to create debugfs directory\n");
1203         } else {
1204                 debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1205                                    &regulator->uA_load);
1206                 debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1207                                    &regulator->min_uV);
1208                 debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1209                                    &regulator->max_uV);
1210         }
1211
1212         /*
1213          * Check now if the regulator is an always on regulator - if
1214          * it is then we don't need to do nearly so much work for
1215          * enable/disable calls.
1216          */
1217         if (!_regulator_can_change_status(rdev) &&
1218             _regulator_is_enabled(rdev))
1219                 regulator->always_on = true;
1220
1221         mutex_unlock(&rdev->mutex);
1222         return regulator;
1223 overflow_err:
1224         list_del(&regulator->list);
1225         kfree(regulator);
1226         mutex_unlock(&rdev->mutex);
1227         return NULL;
1228 }
1229
1230 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1231 {
1232         if (rdev->constraints && rdev->constraints->enable_time)
1233                 return rdev->constraints->enable_time;
1234         if (!rdev->desc->ops->enable_time)
1235                 return rdev->desc->enable_time;
1236         return rdev->desc->ops->enable_time(rdev);
1237 }
1238
1239 static struct regulator_supply_alias *regulator_find_supply_alias(
1240                 struct device *dev, const char *supply)
1241 {
1242         struct regulator_supply_alias *map;
1243
1244         list_for_each_entry(map, &regulator_supply_alias_list, list)
1245                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1246                         return map;
1247
1248         return NULL;
1249 }
1250
1251 static void regulator_supply_alias(struct device **dev, const char **supply)
1252 {
1253         struct regulator_supply_alias *map;
1254
1255         map = regulator_find_supply_alias(*dev, *supply);
1256         if (map) {
1257                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1258                                 *supply, map->alias_supply,
1259                                 dev_name(map->alias_dev));
1260                 *dev = map->alias_dev;
1261                 *supply = map->alias_supply;
1262         }
1263 }
1264
1265 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
1266                                                   const char *supply,
1267                                                   int *ret)
1268 {
1269         struct regulator_dev *r;
1270         struct device_node *node;
1271         struct regulator_map *map;
1272         const char *devname = NULL;
1273
1274         regulator_supply_alias(&dev, &supply);
1275
1276         /* first do a dt based lookup */
1277         if (dev && dev->of_node) {
1278                 node = of_get_regulator(dev, supply);
1279                 if (node) {
1280                         list_for_each_entry(r, &regulator_list, list)
1281                                 if (r->dev.parent &&
1282                                         node == r->dev.of_node)
1283                                         return r;
1284                         *ret = -EPROBE_DEFER;
1285                         return NULL;
1286                 } else {
1287                         /*
1288                          * If we couldn't even get the node then it's
1289                          * not just that the device didn't register
1290                          * yet, there's no node and we'll never
1291                          * succeed.
1292                          */
1293                         *ret = -ENODEV;
1294                 }
1295         }
1296
1297         /* if not found, try doing it non-dt way */
1298         if (dev)
1299                 devname = dev_name(dev);
1300
1301         list_for_each_entry(r, &regulator_list, list)
1302                 if (strcmp(rdev_get_name(r), supply) == 0)
1303                         return r;
1304
1305         list_for_each_entry(map, &regulator_map_list, list) {
1306                 /* If the mapping has a device set up it must match */
1307                 if (map->dev_name &&
1308                     (!devname || strcmp(map->dev_name, devname)))
1309                         continue;
1310
1311                 if (strcmp(map->supply, supply) == 0)
1312                         return map->regulator;
1313         }
1314
1315
1316         return NULL;
1317 }
1318
1319 /* Internal regulator request function */
1320 static struct regulator *_regulator_get(struct device *dev, const char *id,
1321                                         bool exclusive, bool allow_dummy)
1322 {
1323         struct regulator_dev *rdev;
1324         struct regulator *regulator = ERR_PTR(-EPROBE_DEFER);
1325         const char *devname = NULL;
1326         int ret;
1327
1328         if (id == NULL) {
1329                 pr_err("get() with no identifier\n");
1330                 return ERR_PTR(-EINVAL);
1331         }
1332
1333         if (dev)
1334                 devname = dev_name(dev);
1335
1336         if (have_full_constraints())
1337                 ret = -ENODEV;
1338         else
1339                 ret = -EPROBE_DEFER;
1340
1341         mutex_lock(&regulator_list_mutex);
1342
1343         rdev = regulator_dev_lookup(dev, id, &ret);
1344         if (rdev)
1345                 goto found;
1346
1347         regulator = ERR_PTR(ret);
1348
1349         /*
1350          * If we have return value from dev_lookup fail, we do not expect to
1351          * succeed, so, quit with appropriate error value
1352          */
1353         if (ret && ret != -ENODEV)
1354                 goto out;
1355
1356         if (!devname)
1357                 devname = "deviceless";
1358
1359         /*
1360          * Assume that a regulator is physically present and enabled
1361          * even if it isn't hooked up and just provide a dummy.
1362          */
1363         if (have_full_constraints() && allow_dummy) {
1364                 pr_warn("%s supply %s not found, using dummy regulator\n",
1365                         devname, id);
1366
1367                 rdev = dummy_regulator_rdev;
1368                 goto found;
1369         /* Don't log an error when called from regulator_get_optional() */
1370         } else if (!have_full_constraints() || exclusive) {
1371                 dev_warn(dev, "dummy supplies not allowed\n");
1372         }
1373
1374         mutex_unlock(&regulator_list_mutex);
1375         return regulator;
1376
1377 found:
1378         if (rdev->exclusive) {
1379                 regulator = ERR_PTR(-EPERM);
1380                 goto out;
1381         }
1382
1383         if (exclusive && rdev->open_count) {
1384                 regulator = ERR_PTR(-EBUSY);
1385                 goto out;
1386         }
1387
1388         if (!try_module_get(rdev->owner))
1389                 goto out;
1390
1391         regulator = create_regulator(rdev, dev, id);
1392         if (regulator == NULL) {
1393                 regulator = ERR_PTR(-ENOMEM);
1394                 module_put(rdev->owner);
1395                 goto out;
1396         }
1397
1398         rdev->open_count++;
1399         if (exclusive) {
1400                 rdev->exclusive = 1;
1401
1402                 ret = _regulator_is_enabled(rdev);
1403                 if (ret > 0)
1404                         rdev->use_count = 1;
1405                 else
1406                         rdev->use_count = 0;
1407         }
1408
1409 out:
1410         mutex_unlock(&regulator_list_mutex);
1411
1412         return regulator;
1413 }
1414
1415 /**
1416  * regulator_get - lookup and obtain a reference to a regulator.
1417  * @dev: device for regulator "consumer"
1418  * @id: Supply name or regulator ID.
1419  *
1420  * Returns a struct regulator corresponding to the regulator producer,
1421  * or IS_ERR() condition containing errno.
1422  *
1423  * Use of supply names configured via regulator_set_device_supply() is
1424  * strongly encouraged.  It is recommended that the supply name used
1425  * should match the name used for the supply and/or the relevant
1426  * device pins in the datasheet.
1427  */
1428 struct regulator *regulator_get(struct device *dev, const char *id)
1429 {
1430         return _regulator_get(dev, id, false, true);
1431 }
1432 EXPORT_SYMBOL_GPL(regulator_get);
1433
1434 /**
1435  * regulator_get_exclusive - obtain exclusive access to a regulator.
1436  * @dev: device for regulator "consumer"
1437  * @id: Supply name or regulator ID.
1438  *
1439  * Returns a struct regulator corresponding to the regulator producer,
1440  * or IS_ERR() condition containing errno.  Other consumers will be
1441  * unable to obtain this regulator while this reference is held and the
1442  * use count for the regulator will be initialised to reflect the current
1443  * state of the regulator.
1444  *
1445  * This is intended for use by consumers which cannot tolerate shared
1446  * use of the regulator such as those which need to force the
1447  * regulator off for correct operation of the hardware they are
1448  * controlling.
1449  *
1450  * Use of supply names configured via regulator_set_device_supply() is
1451  * strongly encouraged.  It is recommended that the supply name used
1452  * should match the name used for the supply and/or the relevant
1453  * device pins in the datasheet.
1454  */
1455 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1456 {
1457         return _regulator_get(dev, id, true, false);
1458 }
1459 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1460
1461 /**
1462  * regulator_get_optional - obtain optional access to a regulator.
1463  * @dev: device for regulator "consumer"
1464  * @id: Supply name or regulator ID.
1465  *
1466  * Returns a struct regulator corresponding to the regulator producer,
1467  * or IS_ERR() condition containing errno.
1468  *
1469  * This is intended for use by consumers for devices which can have
1470  * some supplies unconnected in normal use, such as some MMC devices.
1471  * It can allow the regulator core to provide stub supplies for other
1472  * supplies requested using normal regulator_get() calls without
1473  * disrupting the operation of drivers that can handle absent
1474  * supplies.
1475  *
1476  * Use of supply names configured via regulator_set_device_supply() is
1477  * strongly encouraged.  It is recommended that the supply name used
1478  * should match the name used for the supply and/or the relevant
1479  * device pins in the datasheet.
1480  */
1481 struct regulator *regulator_get_optional(struct device *dev, const char *id)
1482 {
1483         return _regulator_get(dev, id, false, false);
1484 }
1485 EXPORT_SYMBOL_GPL(regulator_get_optional);
1486
1487 /* regulator_list_mutex lock held by regulator_put() */
1488 static void _regulator_put(struct regulator *regulator)
1489 {
1490         struct regulator_dev *rdev;
1491
1492         if (regulator == NULL || IS_ERR(regulator))
1493                 return;
1494
1495         rdev = regulator->rdev;
1496
1497         debugfs_remove_recursive(regulator->debugfs);
1498
1499         /* remove any sysfs entries */
1500         if (regulator->dev)
1501                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1502         mutex_lock(&rdev->mutex);
1503         kfree(regulator->supply_name);
1504         list_del(&regulator->list);
1505         kfree(regulator);
1506
1507         rdev->open_count--;
1508         rdev->exclusive = 0;
1509         mutex_unlock(&rdev->mutex);
1510
1511         module_put(rdev->owner);
1512 }
1513
1514 /**
1515  * regulator_put - "free" the regulator source
1516  * @regulator: regulator source
1517  *
1518  * Note: drivers must ensure that all regulator_enable calls made on this
1519  * regulator source are balanced by regulator_disable calls prior to calling
1520  * this function.
1521  */
1522 void regulator_put(struct regulator *regulator)
1523 {
1524         mutex_lock(&regulator_list_mutex);
1525         _regulator_put(regulator);
1526         mutex_unlock(&regulator_list_mutex);
1527 }
1528 EXPORT_SYMBOL_GPL(regulator_put);
1529
1530 /**
1531  * regulator_register_supply_alias - Provide device alias for supply lookup
1532  *
1533  * @dev: device that will be given as the regulator "consumer"
1534  * @id: Supply name or regulator ID
1535  * @alias_dev: device that should be used to lookup the supply
1536  * @alias_id: Supply name or regulator ID that should be used to lookup the
1537  * supply
1538  *
1539  * All lookups for id on dev will instead be conducted for alias_id on
1540  * alias_dev.
1541  */
1542 int regulator_register_supply_alias(struct device *dev, const char *id,
1543                                     struct device *alias_dev,
1544                                     const char *alias_id)
1545 {
1546         struct regulator_supply_alias *map;
1547
1548         map = regulator_find_supply_alias(dev, id);
1549         if (map)
1550                 return -EEXIST;
1551
1552         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
1553         if (!map)
1554                 return -ENOMEM;
1555
1556         map->src_dev = dev;
1557         map->src_supply = id;
1558         map->alias_dev = alias_dev;
1559         map->alias_supply = alias_id;
1560
1561         list_add(&map->list, &regulator_supply_alias_list);
1562
1563         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
1564                 id, dev_name(dev), alias_id, dev_name(alias_dev));
1565
1566         return 0;
1567 }
1568 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
1569
1570 /**
1571  * regulator_unregister_supply_alias - Remove device alias
1572  *
1573  * @dev: device that will be given as the regulator "consumer"
1574  * @id: Supply name or regulator ID
1575  *
1576  * Remove a lookup alias if one exists for id on dev.
1577  */
1578 void regulator_unregister_supply_alias(struct device *dev, const char *id)
1579 {
1580         struct regulator_supply_alias *map;
1581
1582         map = regulator_find_supply_alias(dev, id);
1583         if (map) {
1584                 list_del(&map->list);
1585                 kfree(map);
1586         }
1587 }
1588 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
1589
1590 /**
1591  * regulator_bulk_register_supply_alias - register multiple aliases
1592  *
1593  * @dev: device that will be given as the regulator "consumer"
1594  * @id: List of supply names or regulator IDs
1595  * @alias_dev: device that should be used to lookup the supply
1596  * @alias_id: List of supply names or regulator IDs that should be used to
1597  * lookup the supply
1598  * @num_id: Number of aliases to register
1599  *
1600  * @return 0 on success, an errno on failure.
1601  *
1602  * This helper function allows drivers to register several supply
1603  * aliases in one operation.  If any of the aliases cannot be
1604  * registered any aliases that were registered will be removed
1605  * before returning to the caller.
1606  */
1607 int regulator_bulk_register_supply_alias(struct device *dev,
1608                                          const char *const *id,
1609                                          struct device *alias_dev,
1610                                          const char *const *alias_id,
1611                                          int num_id)
1612 {
1613         int i;
1614         int ret;
1615
1616         for (i = 0; i < num_id; ++i) {
1617                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
1618                                                       alias_id[i]);
1619                 if (ret < 0)
1620                         goto err;
1621         }
1622
1623         return 0;
1624
1625 err:
1626         dev_err(dev,
1627                 "Failed to create supply alias %s,%s -> %s,%s\n",
1628                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
1629
1630         while (--i >= 0)
1631                 regulator_unregister_supply_alias(dev, id[i]);
1632
1633         return ret;
1634 }
1635 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
1636
1637 /**
1638  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
1639  *
1640  * @dev: device that will be given as the regulator "consumer"
1641  * @id: List of supply names or regulator IDs
1642  * @num_id: Number of aliases to unregister
1643  *
1644  * This helper function allows drivers to unregister several supply
1645  * aliases in one operation.
1646  */
1647 void regulator_bulk_unregister_supply_alias(struct device *dev,
1648                                             const char *const *id,
1649                                             int num_id)
1650 {
1651         int i;
1652
1653         for (i = 0; i < num_id; ++i)
1654                 regulator_unregister_supply_alias(dev, id[i]);
1655 }
1656 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
1657
1658
1659 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
1660 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
1661                                 const struct regulator_config *config)
1662 {
1663         struct regulator_enable_gpio *pin;
1664         struct gpio_desc *gpiod;
1665         int ret;
1666
1667         gpiod = gpio_to_desc(config->ena_gpio);
1668
1669         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
1670                 if (pin->gpiod == gpiod) {
1671                         rdev_dbg(rdev, "GPIO %d is already used\n",
1672                                 config->ena_gpio);
1673                         goto update_ena_gpio_to_rdev;
1674                 }
1675         }
1676
1677         ret = gpio_request_one(config->ena_gpio,
1678                                 GPIOF_DIR_OUT | config->ena_gpio_flags,
1679                                 rdev_get_name(rdev));
1680         if (ret)
1681                 return ret;
1682
1683         pin = kzalloc(sizeof(struct regulator_enable_gpio), GFP_KERNEL);
1684         if (pin == NULL) {
1685                 gpio_free(config->ena_gpio);
1686                 return -ENOMEM;
1687         }
1688
1689         pin->gpiod = gpiod;
1690         pin->ena_gpio_invert = config->ena_gpio_invert;
1691         list_add(&pin->list, &regulator_ena_gpio_list);
1692
1693 update_ena_gpio_to_rdev:
1694         pin->request_count++;
1695         rdev->ena_pin = pin;
1696         return 0;
1697 }
1698
1699 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
1700 {
1701         struct regulator_enable_gpio *pin, *n;
1702
1703         if (!rdev->ena_pin)
1704                 return;
1705
1706         /* Free the GPIO only in case of no use */
1707         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
1708                 if (pin->gpiod == rdev->ena_pin->gpiod) {
1709                         if (pin->request_count <= 1) {
1710                                 pin->request_count = 0;
1711                                 gpiod_put(pin->gpiod);
1712                                 list_del(&pin->list);
1713                                 kfree(pin);
1714                                 rdev->ena_pin = NULL;
1715                                 return;
1716                         } else {
1717                                 pin->request_count--;
1718                         }
1719                 }
1720         }
1721 }
1722
1723 /**
1724  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
1725  * @rdev: regulator_dev structure
1726  * @enable: enable GPIO at initial use?
1727  *
1728  * GPIO is enabled in case of initial use. (enable_count is 0)
1729  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
1730  */
1731 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
1732 {
1733         struct regulator_enable_gpio *pin = rdev->ena_pin;
1734
1735         if (!pin)
1736                 return -EINVAL;
1737
1738         if (enable) {
1739                 /* Enable GPIO at initial use */
1740                 if (pin->enable_count == 0)
1741                         gpiod_set_value_cansleep(pin->gpiod,
1742                                                  !pin->ena_gpio_invert);
1743
1744                 pin->enable_count++;
1745         } else {
1746                 if (pin->enable_count > 1) {
1747                         pin->enable_count--;
1748                         return 0;
1749                 }
1750
1751                 /* Disable GPIO if not used */
1752                 if (pin->enable_count <= 1) {
1753                         gpiod_set_value_cansleep(pin->gpiod,
1754                                                  pin->ena_gpio_invert);
1755                         pin->enable_count = 0;
1756                 }
1757         }
1758
1759         return 0;
1760 }
1761
1762 /**
1763  * _regulator_enable_delay - a delay helper function
1764  * @delay: time to delay in microseconds
1765  *
1766  * Delay for the requested amount of time as per the guidelines in:
1767  *
1768  *     Documentation/timers/timers-howto.txt
1769  *
1770  * The assumption here is that regulators will never be enabled in
1771  * atomic context and therefore sleeping functions can be used.
1772  */
1773 static void _regulator_enable_delay(unsigned int delay)
1774 {
1775         unsigned int ms = delay / 1000;
1776         unsigned int us = delay % 1000;
1777
1778         if (ms > 0) {
1779                 /*
1780                  * For small enough values, handle super-millisecond
1781                  * delays in the usleep_range() call below.
1782                  */
1783                 if (ms < 20)
1784                         us += ms * 1000;
1785                 else
1786                         msleep(ms);
1787         }
1788
1789         /*
1790          * Give the scheduler some room to coalesce with any other
1791          * wakeup sources. For delays shorter than 10 us, don't even
1792          * bother setting up high-resolution timers and just busy-
1793          * loop.
1794          */
1795         if (us >= 10)
1796                 usleep_range(us, us + 100);
1797         else
1798                 udelay(us);
1799 }
1800
1801 static int _regulator_do_enable(struct regulator_dev *rdev)
1802 {
1803         int ret, delay;
1804
1805         /* Query before enabling in case configuration dependent.  */
1806         ret = _regulator_get_enable_time(rdev);
1807         if (ret >= 0) {
1808                 delay = ret;
1809         } else {
1810                 rdev_warn(rdev, "enable_time() failed: %d\n", ret);
1811                 delay = 0;
1812         }
1813
1814         trace_regulator_enable(rdev_get_name(rdev));
1815
1816         if (rdev->desc->off_on_delay) {
1817                 /* if needed, keep a distance of off_on_delay from last time
1818                  * this regulator was disabled.
1819                  */
1820                 unsigned long start_jiffy = jiffies;
1821                 unsigned long intended, max_delay, remaining;
1822
1823                 max_delay = usecs_to_jiffies(rdev->desc->off_on_delay);
1824                 intended = rdev->last_off_jiffy + max_delay;
1825
1826                 if (time_before(start_jiffy, intended)) {
1827                         /* calc remaining jiffies to deal with one-time
1828                          * timer wrapping.
1829                          * in case of multiple timer wrapping, either it can be
1830                          * detected by out-of-range remaining, or it cannot be
1831                          * detected and we gets a panelty of
1832                          * _regulator_enable_delay().
1833                          */
1834                         remaining = intended - start_jiffy;
1835                         if (remaining <= max_delay)
1836                                 _regulator_enable_delay(
1837                                                 jiffies_to_usecs(remaining));
1838                 }
1839         }
1840
1841         if (rdev->ena_pin) {
1842                 if (!rdev->ena_gpio_state) {
1843                         ret = regulator_ena_gpio_ctrl(rdev, true);
1844                         if (ret < 0)
1845                                 return ret;
1846                         rdev->ena_gpio_state = 1;
1847                 }
1848         } else if (rdev->desc->ops->enable) {
1849                 ret = rdev->desc->ops->enable(rdev);
1850                 if (ret < 0)
1851                         return ret;
1852         } else {
1853                 return -EINVAL;
1854         }
1855
1856         /* Allow the regulator to ramp; it would be useful to extend
1857          * this for bulk operations so that the regulators can ramp
1858          * together.  */
1859         trace_regulator_enable_delay(rdev_get_name(rdev));
1860
1861         _regulator_enable_delay(delay);
1862
1863         trace_regulator_enable_complete(rdev_get_name(rdev));
1864
1865         return 0;
1866 }
1867
1868 /* locks held by regulator_enable() */
1869 static int _regulator_enable(struct regulator_dev *rdev)
1870 {
1871         int ret;
1872
1873         /* check voltage and requested load before enabling */
1874         if (rdev->constraints &&
1875             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1876                 drms_uA_update(rdev);
1877
1878         if (rdev->use_count == 0) {
1879                 /* The regulator may on if it's not switchable or left on */
1880                 ret = _regulator_is_enabled(rdev);
1881                 if (ret == -EINVAL || ret == 0) {
1882                         if (!_regulator_can_change_status(rdev))
1883                                 return -EPERM;
1884
1885                         ret = _regulator_do_enable(rdev);
1886                         if (ret < 0)
1887                                 return ret;
1888
1889                 } else if (ret < 0) {
1890                         rdev_err(rdev, "is_enabled() failed: %d\n", ret);
1891                         return ret;
1892                 }
1893                 /* Fallthrough on positive return values - already enabled */
1894         }
1895
1896         rdev->use_count++;
1897
1898         return 0;
1899 }
1900
1901 /**
1902  * regulator_enable - enable regulator output
1903  * @regulator: regulator source
1904  *
1905  * Request that the regulator be enabled with the regulator output at
1906  * the predefined voltage or current value.  Calls to regulator_enable()
1907  * must be balanced with calls to regulator_disable().
1908  *
1909  * NOTE: the output value can be set by other drivers, boot loader or may be
1910  * hardwired in the regulator.
1911  */
1912 int regulator_enable(struct regulator *regulator)
1913 {
1914         struct regulator_dev *rdev = regulator->rdev;
1915         int ret = 0;
1916
1917         if (regulator->always_on)
1918                 return 0;
1919
1920         if (rdev->supply) {
1921                 ret = regulator_enable(rdev->supply);
1922                 if (ret != 0)
1923                         return ret;
1924         }
1925
1926         mutex_lock(&rdev->mutex);
1927         ret = _regulator_enable(rdev);
1928         mutex_unlock(&rdev->mutex);
1929
1930         if (ret != 0 && rdev->supply)
1931                 regulator_disable(rdev->supply);
1932
1933         return ret;
1934 }
1935 EXPORT_SYMBOL_GPL(regulator_enable);
1936
1937 static int _regulator_do_disable(struct regulator_dev *rdev)
1938 {
1939         int ret;
1940
1941         trace_regulator_disable(rdev_get_name(rdev));
1942
1943         if (rdev->ena_pin) {
1944                 if (rdev->ena_gpio_state) {
1945                         ret = regulator_ena_gpio_ctrl(rdev, false);
1946                         if (ret < 0)
1947                                 return ret;
1948                         rdev->ena_gpio_state = 0;
1949                 }
1950
1951         } else if (rdev->desc->ops->disable) {
1952                 ret = rdev->desc->ops->disable(rdev);
1953                 if (ret != 0)
1954                         return ret;
1955         }
1956
1957         /* cares about last_off_jiffy only if off_on_delay is required by
1958          * device.
1959          */
1960         if (rdev->desc->off_on_delay)
1961                 rdev->last_off_jiffy = jiffies;
1962
1963         trace_regulator_disable_complete(rdev_get_name(rdev));
1964
1965         return 0;
1966 }
1967
1968 /* locks held by regulator_disable() */
1969 static int _regulator_disable(struct regulator_dev *rdev)
1970 {
1971         int ret = 0;
1972
1973         if (WARN(rdev->use_count <= 0,
1974                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
1975                 return -EIO;
1976
1977         /* are we the last user and permitted to disable ? */
1978         if (rdev->use_count == 1 &&
1979             (rdev->constraints && !rdev->constraints->always_on)) {
1980
1981                 /* we are last user */
1982                 if (_regulator_can_change_status(rdev)) {
1983                         ret = _notifier_call_chain(rdev,
1984                                                    REGULATOR_EVENT_PRE_DISABLE,
1985                                                    NULL);
1986                         if (ret & NOTIFY_STOP_MASK)
1987                                 return -EINVAL;
1988
1989                         ret = _regulator_do_disable(rdev);
1990                         if (ret < 0) {
1991                                 rdev_err(rdev, "failed to disable\n");
1992                                 _notifier_call_chain(rdev,
1993                                                 REGULATOR_EVENT_ABORT_DISABLE,
1994                                                 NULL);
1995                                 return ret;
1996                         }
1997                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1998                                         NULL);
1999                 }
2000
2001                 rdev->use_count = 0;
2002         } else if (rdev->use_count > 1) {
2003
2004                 if (rdev->constraints &&
2005                         (rdev->constraints->valid_ops_mask &
2006                         REGULATOR_CHANGE_DRMS))
2007                         drms_uA_update(rdev);
2008
2009                 rdev->use_count--;
2010         }
2011
2012         return ret;
2013 }
2014
2015 /**
2016  * regulator_disable - disable regulator output
2017  * @regulator: regulator source
2018  *
2019  * Disable the regulator output voltage or current.  Calls to
2020  * regulator_enable() must be balanced with calls to
2021  * regulator_disable().
2022  *
2023  * NOTE: this will only disable the regulator output if no other consumer
2024  * devices have it enabled, the regulator device supports disabling and
2025  * machine constraints permit this operation.
2026  */
2027 int regulator_disable(struct regulator *regulator)
2028 {
2029         struct regulator_dev *rdev = regulator->rdev;
2030         int ret = 0;
2031
2032         if (regulator->always_on)
2033                 return 0;
2034
2035         mutex_lock(&rdev->mutex);
2036         ret = _regulator_disable(rdev);
2037         mutex_unlock(&rdev->mutex);
2038
2039         if (ret == 0 && rdev->supply)
2040                 regulator_disable(rdev->supply);
2041
2042         return ret;
2043 }
2044 EXPORT_SYMBOL_GPL(regulator_disable);
2045
2046 /* locks held by regulator_force_disable() */
2047 static int _regulator_force_disable(struct regulator_dev *rdev)
2048 {
2049         int ret = 0;
2050
2051         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2052                         REGULATOR_EVENT_PRE_DISABLE, NULL);
2053         if (ret & NOTIFY_STOP_MASK)
2054                 return -EINVAL;
2055
2056         ret = _regulator_do_disable(rdev);
2057         if (ret < 0) {
2058                 rdev_err(rdev, "failed to force disable\n");
2059                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2060                                 REGULATOR_EVENT_ABORT_DISABLE, NULL);
2061                 return ret;
2062         }
2063
2064         _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
2065                         REGULATOR_EVENT_DISABLE, NULL);
2066
2067         return 0;
2068 }
2069
2070 /**
2071  * regulator_force_disable - force disable regulator output
2072  * @regulator: regulator source
2073  *
2074  * Forcibly disable the regulator output voltage or current.
2075  * NOTE: this *will* disable the regulator output even if other consumer
2076  * devices have it enabled. This should be used for situations when device
2077  * damage will likely occur if the regulator is not disabled (e.g. over temp).
2078  */
2079 int regulator_force_disable(struct regulator *regulator)
2080 {
2081         struct regulator_dev *rdev = regulator->rdev;
2082         int ret;
2083
2084         mutex_lock(&rdev->mutex);
2085         regulator->uA_load = 0;
2086         ret = _regulator_force_disable(regulator->rdev);
2087         mutex_unlock(&rdev->mutex);
2088
2089         if (rdev->supply)
2090                 while (rdev->open_count--)
2091                         regulator_disable(rdev->supply);
2092
2093         return ret;
2094 }
2095 EXPORT_SYMBOL_GPL(regulator_force_disable);
2096
2097 static void regulator_disable_work(struct work_struct *work)
2098 {
2099         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
2100                                                   disable_work.work);
2101         int count, i, ret;
2102
2103         mutex_lock(&rdev->mutex);
2104
2105         BUG_ON(!rdev->deferred_disables);
2106
2107         count = rdev->deferred_disables;
2108         rdev->deferred_disables = 0;
2109
2110         for (i = 0; i < count; i++) {
2111                 ret = _regulator_disable(rdev);
2112                 if (ret != 0)
2113                         rdev_err(rdev, "Deferred disable failed: %d\n", ret);
2114         }
2115
2116         mutex_unlock(&rdev->mutex);
2117
2118         if (rdev->supply) {
2119                 for (i = 0; i < count; i++) {
2120                         ret = regulator_disable(rdev->supply);
2121                         if (ret != 0) {
2122                                 rdev_err(rdev,
2123                                          "Supply disable failed: %d\n", ret);
2124                         }
2125                 }
2126         }
2127 }
2128
2129 /**
2130  * regulator_disable_deferred - disable regulator output with delay
2131  * @regulator: regulator source
2132  * @ms: miliseconds until the regulator is disabled
2133  *
2134  * Execute regulator_disable() on the regulator after a delay.  This
2135  * is intended for use with devices that require some time to quiesce.
2136  *
2137  * NOTE: this will only disable the regulator output if no other consumer
2138  * devices have it enabled, the regulator device supports disabling and
2139  * machine constraints permit this operation.
2140  */
2141 int regulator_disable_deferred(struct regulator *regulator, int ms)
2142 {
2143         struct regulator_dev *rdev = regulator->rdev;
2144         int ret;
2145
2146         if (regulator->always_on)
2147                 return 0;
2148
2149         if (!ms)
2150                 return regulator_disable(regulator);
2151
2152         mutex_lock(&rdev->mutex);
2153         rdev->deferred_disables++;
2154         mutex_unlock(&rdev->mutex);
2155
2156         ret = queue_delayed_work(system_power_efficient_wq,
2157                                  &rdev->disable_work,
2158                                  msecs_to_jiffies(ms));
2159         if (ret < 0)
2160                 return ret;
2161         else
2162                 return 0;
2163 }
2164 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
2165
2166 static int _regulator_is_enabled(struct regulator_dev *rdev)
2167 {
2168         /* A GPIO control always takes precedence */
2169         if (rdev->ena_pin)
2170                 return rdev->ena_gpio_state;
2171
2172         /* If we don't know then assume that the regulator is always on */
2173         if (!rdev->desc->ops->is_enabled)
2174                 return 1;
2175
2176         return rdev->desc->ops->is_enabled(rdev);
2177 }
2178
2179 /**
2180  * regulator_is_enabled - is the regulator output enabled
2181  * @regulator: regulator source
2182  *
2183  * Returns positive if the regulator driver backing the source/client
2184  * has requested that the device be enabled, zero if it hasn't, else a
2185  * negative errno code.
2186  *
2187  * Note that the device backing this regulator handle can have multiple
2188  * users, so it might be enabled even if regulator_enable() was never
2189  * called for this particular source.
2190  */
2191 int regulator_is_enabled(struct regulator *regulator)
2192 {
2193         int ret;
2194
2195         if (regulator->always_on)
2196                 return 1;
2197
2198         mutex_lock(&regulator->rdev->mutex);
2199         ret = _regulator_is_enabled(regulator->rdev);
2200         mutex_unlock(&regulator->rdev->mutex);
2201
2202         return ret;
2203 }
2204 EXPORT_SYMBOL_GPL(regulator_is_enabled);
2205
2206 /**
2207  * regulator_can_change_voltage - check if regulator can change voltage
2208  * @regulator: regulator source
2209  *
2210  * Returns positive if the regulator driver backing the source/client
2211  * can change its voltage, false otherwise. Useful for detecting fixed
2212  * or dummy regulators and disabling voltage change logic in the client
2213  * driver.
2214  */
2215 int regulator_can_change_voltage(struct regulator *regulator)
2216 {
2217         struct regulator_dev    *rdev = regulator->rdev;
2218
2219         if (rdev->constraints &&
2220             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2221                 if (rdev->desc->n_voltages - rdev->desc->linear_min_sel > 1)
2222                         return 1;
2223
2224                 if (rdev->desc->continuous_voltage_range &&
2225                     rdev->constraints->min_uV && rdev->constraints->max_uV &&
2226                     rdev->constraints->min_uV != rdev->constraints->max_uV)
2227                         return 1;
2228         }
2229
2230         return 0;
2231 }
2232 EXPORT_SYMBOL_GPL(regulator_can_change_voltage);
2233
2234 /**
2235  * regulator_count_voltages - count regulator_list_voltage() selectors
2236  * @regulator: regulator source
2237  *
2238  * Returns number of selectors, or negative errno.  Selectors are
2239  * numbered starting at zero, and typically correspond to bitfields
2240  * in hardware registers.
2241  */
2242 int regulator_count_voltages(struct regulator *regulator)
2243 {
2244         struct regulator_dev    *rdev = regulator->rdev;
2245
2246         if (rdev->desc->n_voltages)
2247                 return rdev->desc->n_voltages;
2248
2249         if (!rdev->supply)
2250                 return -EINVAL;
2251
2252         return regulator_count_voltages(rdev->supply);
2253 }
2254 EXPORT_SYMBOL_GPL(regulator_count_voltages);
2255
2256 /**
2257  * regulator_list_voltage - enumerate supported voltages
2258  * @regulator: regulator source
2259  * @selector: identify voltage to list
2260  * Context: can sleep
2261  *
2262  * Returns a voltage that can be passed to @regulator_set_voltage(),
2263  * zero if this selector code can't be used on this system, or a
2264  * negative errno.
2265  */
2266 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
2267 {
2268         struct regulator_dev *rdev = regulator->rdev;
2269         const struct regulator_ops *ops = rdev->desc->ops;
2270         int ret;
2271
2272         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
2273                 return rdev->desc->fixed_uV;
2274
2275         if (ops->list_voltage) {
2276                 if (selector >= rdev->desc->n_voltages)
2277                         return -EINVAL;
2278                 mutex_lock(&rdev->mutex);
2279                 ret = ops->list_voltage(rdev, selector);
2280                 mutex_unlock(&rdev->mutex);
2281         } else if (rdev->supply) {
2282                 ret = regulator_list_voltage(rdev->supply, selector);
2283         } else {
2284                 return -EINVAL;
2285         }
2286
2287         if (ret > 0) {
2288                 if (ret < rdev->constraints->min_uV)
2289                         ret = 0;
2290                 else if (ret > rdev->constraints->max_uV)
2291                         ret = 0;
2292         }
2293
2294         return ret;
2295 }
2296 EXPORT_SYMBOL_GPL(regulator_list_voltage);
2297
2298 /**
2299  * regulator_get_regmap - get the regulator's register map
2300  * @regulator: regulator source
2301  *
2302  * Returns the register map for the given regulator, or an ERR_PTR value
2303  * if the regulator doesn't use regmap.
2304  */
2305 struct regmap *regulator_get_regmap(struct regulator *regulator)
2306 {
2307         struct regmap *map = regulator->rdev->regmap;
2308
2309         return map ? map : ERR_PTR(-EOPNOTSUPP);
2310 }
2311
2312 /**
2313  * regulator_get_hardware_vsel_register - get the HW voltage selector register
2314  * @regulator: regulator source
2315  * @vsel_reg: voltage selector register, output parameter
2316  * @vsel_mask: mask for voltage selector bitfield, output parameter
2317  *
2318  * Returns the hardware register offset and bitmask used for setting the
2319  * regulator voltage. This might be useful when configuring voltage-scaling
2320  * hardware or firmware that can make I2C requests behind the kernel's back,
2321  * for example.
2322  *
2323  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
2324  * and 0 is returned, otherwise a negative errno is returned.
2325  */
2326 int regulator_get_hardware_vsel_register(struct regulator *regulator,
2327                                          unsigned *vsel_reg,
2328                                          unsigned *vsel_mask)
2329 {
2330         struct regulator_dev *rdev = regulator->rdev;
2331         const struct regulator_ops *ops = rdev->desc->ops;
2332
2333         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2334                 return -EOPNOTSUPP;
2335
2336          *vsel_reg = rdev->desc->vsel_reg;
2337          *vsel_mask = rdev->desc->vsel_mask;
2338
2339          return 0;
2340 }
2341 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
2342
2343 /**
2344  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
2345  * @regulator: regulator source
2346  * @selector: identify voltage to list
2347  *
2348  * Converts the selector to a hardware-specific voltage selector that can be
2349  * directly written to the regulator registers. The address of the voltage
2350  * register can be determined by calling @regulator_get_hardware_vsel_register.
2351  *
2352  * On error a negative errno is returned.
2353  */
2354 int regulator_list_hardware_vsel(struct regulator *regulator,
2355                                  unsigned selector)
2356 {
2357         struct regulator_dev *rdev = regulator->rdev;
2358         const struct regulator_ops *ops = rdev->desc->ops;
2359
2360         if (selector >= rdev->desc->n_voltages)
2361                 return -EINVAL;
2362         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
2363                 return -EOPNOTSUPP;
2364
2365         return selector;
2366 }
2367 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
2368
2369 /**
2370  * regulator_get_linear_step - return the voltage step size between VSEL values
2371  * @regulator: regulator source
2372  *
2373  * Returns the voltage step size between VSEL values for linear
2374  * regulators, or return 0 if the regulator isn't a linear regulator.
2375  */
2376 unsigned int regulator_get_linear_step(struct regulator *regulator)
2377 {
2378         struct regulator_dev *rdev = regulator->rdev;
2379
2380         return rdev->desc->uV_step;
2381 }
2382 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
2383
2384 /**
2385  * regulator_is_supported_voltage - check if a voltage range can be supported
2386  *
2387  * @regulator: Regulator to check.
2388  * @min_uV: Minimum required voltage in uV.
2389  * @max_uV: Maximum required voltage in uV.
2390  *
2391  * Returns a boolean or a negative error code.
2392  */
2393 int regulator_is_supported_voltage(struct regulator *regulator,
2394                                    int min_uV, int max_uV)
2395 {
2396         struct regulator_dev *rdev = regulator->rdev;
2397         int i, voltages, ret;
2398
2399         /* If we can't change voltage check the current voltage */
2400         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2401                 ret = regulator_get_voltage(regulator);
2402                 if (ret >= 0)
2403                         return min_uV <= ret && ret <= max_uV;
2404                 else
2405                         return ret;
2406         }
2407
2408         /* Any voltage within constrains range is fine? */
2409         if (rdev->desc->continuous_voltage_range)
2410                 return min_uV >= rdev->constraints->min_uV &&
2411                                 max_uV <= rdev->constraints->max_uV;
2412
2413         ret = regulator_count_voltages(regulator);
2414         if (ret < 0)
2415                 return ret;
2416         voltages = ret;
2417
2418         for (i = 0; i < voltages; i++) {
2419                 ret = regulator_list_voltage(regulator, i);
2420
2421                 if (ret >= min_uV && ret <= max_uV)
2422                         return 1;
2423         }
2424
2425         return 0;
2426 }
2427 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
2428
2429 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
2430                                        int min_uV, int max_uV,
2431                                        unsigned *selector)
2432 {
2433         struct pre_voltage_change_data data;
2434         int ret;
2435
2436         data.old_uV = _regulator_get_voltage(rdev);
2437         data.min_uV = min_uV;
2438         data.max_uV = max_uV;
2439         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2440                                    &data);
2441         if (ret & NOTIFY_STOP_MASK)
2442                 return -EINVAL;
2443
2444         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
2445         if (ret >= 0)
2446                 return ret;
2447
2448         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2449                              (void *)data.old_uV);
2450
2451         return ret;
2452 }
2453
2454 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
2455                                            int uV, unsigned selector)
2456 {
2457         struct pre_voltage_change_data data;
2458         int ret;
2459
2460         data.old_uV = _regulator_get_voltage(rdev);
2461         data.min_uV = uV;
2462         data.max_uV = uV;
2463         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
2464                                    &data);
2465         if (ret & NOTIFY_STOP_MASK)
2466                 return -EINVAL;
2467
2468         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
2469         if (ret >= 0)
2470                 return ret;
2471
2472         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
2473                              (void *)data.old_uV);
2474
2475         return ret;
2476 }
2477
2478 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
2479                                      int min_uV, int max_uV)
2480 {
2481         int ret;
2482         int delay = 0;
2483         int best_val = 0;
2484         unsigned int selector;
2485         int old_selector = -1;
2486
2487         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
2488
2489         min_uV += rdev->constraints->uV_offset;
2490         max_uV += rdev->constraints->uV_offset;
2491
2492         /*
2493          * If we can't obtain the old selector there is not enough
2494          * info to call set_voltage_time_sel().
2495          */
2496         if (_regulator_is_enabled(rdev) &&
2497             rdev->desc->ops->set_voltage_time_sel &&
2498             rdev->desc->ops->get_voltage_sel) {
2499                 old_selector = rdev->desc->ops->get_voltage_sel(rdev);
2500                 if (old_selector < 0)
2501                         return old_selector;
2502         }
2503
2504         if (rdev->desc->ops->set_voltage) {
2505                 ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
2506                                                   &selector);
2507
2508                 if (ret >= 0) {
2509                         if (rdev->desc->ops->list_voltage)
2510                                 best_val = rdev->desc->ops->list_voltage(rdev,
2511                                                                          selector);
2512                         else
2513                                 best_val = _regulator_get_voltage(rdev);
2514                 }
2515
2516         } else if (rdev->desc->ops->set_voltage_sel) {
2517                 if (rdev->desc->ops->map_voltage) {
2518                         ret = rdev->desc->ops->map_voltage(rdev, min_uV,
2519                                                            max_uV);
2520                 } else {
2521                         if (rdev->desc->ops->list_voltage ==
2522                             regulator_list_voltage_linear)
2523                                 ret = regulator_map_voltage_linear(rdev,
2524                                                                 min_uV, max_uV);
2525                         else if (rdev->desc->ops->list_voltage ==
2526                                  regulator_list_voltage_linear_range)
2527                                 ret = regulator_map_voltage_linear_range(rdev,
2528                                                                 min_uV, max_uV);
2529                         else
2530                                 ret = regulator_map_voltage_iterate(rdev,
2531                                                                 min_uV, max_uV);
2532                 }
2533
2534                 if (ret >= 0) {
2535                         best_val = rdev->desc->ops->list_voltage(rdev, ret);
2536                         if (min_uV <= best_val && max_uV >= best_val) {
2537                                 selector = ret;
2538                                 if (old_selector == selector)
2539                                         ret = 0;
2540                                 else
2541                                         ret = _regulator_call_set_voltage_sel(
2542                                                 rdev, best_val, selector);
2543                         } else {
2544                                 ret = -EINVAL;
2545                         }
2546                 }
2547         } else {
2548                 ret = -EINVAL;
2549         }
2550
2551         /* Call set_voltage_time_sel if successfully obtained old_selector */
2552         if (ret == 0 && !rdev->constraints->ramp_disable && old_selector >= 0
2553                 && old_selector != selector) {
2554
2555                 delay = rdev->desc->ops->set_voltage_time_sel(rdev,
2556                                                 old_selector, selector);
2557                 if (delay < 0) {
2558                         rdev_warn(rdev, "set_voltage_time_sel() failed: %d\n",
2559                                   delay);
2560                         delay = 0;
2561                 }
2562
2563                 /* Insert any necessary delays */
2564                 if (delay >= 1000) {
2565                         mdelay(delay / 1000);
2566                         udelay(delay % 1000);
2567                 } else if (delay) {
2568                         udelay(delay);
2569                 }
2570         }
2571
2572         if (ret == 0 && best_val >= 0) {
2573                 unsigned long data = best_val;
2574
2575                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
2576                                      (void *)data);
2577         }
2578
2579         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
2580
2581         return ret;
2582 }
2583
2584 /**
2585  * regulator_set_voltage - set regulator output voltage
2586  * @regulator: regulator source
2587  * @min_uV: Minimum required voltage in uV
2588  * @max_uV: Maximum acceptable voltage in uV
2589  *
2590  * Sets a voltage regulator to the desired output voltage. This can be set
2591  * during any regulator state. IOW, regulator can be disabled or enabled.
2592  *
2593  * If the regulator is enabled then the voltage will change to the new value
2594  * immediately otherwise if the regulator is disabled the regulator will
2595  * output at the new voltage when enabled.
2596  *
2597  * NOTE: If the regulator is shared between several devices then the lowest
2598  * request voltage that meets the system constraints will be used.
2599  * Regulator system constraints must be set for this regulator before
2600  * calling this function otherwise this call will fail.
2601  */
2602 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
2603 {
2604         struct regulator_dev *rdev = regulator->rdev;
2605         int ret = 0;
2606         int old_min_uV, old_max_uV;
2607         int current_uV;
2608
2609         mutex_lock(&rdev->mutex);
2610
2611         /* If we're setting the same range as last time the change
2612          * should be a noop (some cpufreq implementations use the same
2613          * voltage for multiple frequencies, for example).
2614          */
2615         if (regulator->min_uV == min_uV && regulator->max_uV == max_uV)
2616                 goto out;
2617
2618         /* If we're trying to set a range that overlaps the current voltage,
2619          * return succesfully even though the regulator does not support
2620          * changing the voltage.
2621          */
2622         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
2623                 current_uV = _regulator_get_voltage(rdev);
2624                 if (min_uV <= current_uV && current_uV <= max_uV) {
2625                         regulator->min_uV = min_uV;
2626                         regulator->max_uV = max_uV;
2627                         goto out;
2628                 }
2629         }
2630
2631         /* sanity check */
2632         if (!rdev->desc->ops->set_voltage &&
2633             !rdev->desc->ops->set_voltage_sel) {
2634                 ret = -EINVAL;
2635                 goto out;
2636         }
2637
2638         /* constraints check */
2639         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2640         if (ret < 0)
2641                 goto out;
2642
2643         /* restore original values in case of error */
2644         old_min_uV = regulator->min_uV;
2645         old_max_uV = regulator->max_uV;
2646         regulator->min_uV = min_uV;
2647         regulator->max_uV = max_uV;
2648
2649         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2650         if (ret < 0)
2651                 goto out2;
2652
2653         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2654         if (ret < 0)
2655                 goto out2;
2656
2657 out:
2658         mutex_unlock(&rdev->mutex);
2659         return ret;
2660 out2:
2661         regulator->min_uV = old_min_uV;
2662         regulator->max_uV = old_max_uV;
2663         mutex_unlock(&rdev->mutex);
2664         return ret;
2665 }
2666 EXPORT_SYMBOL_GPL(regulator_set_voltage);
2667
2668 /**
2669  * regulator_set_voltage_time - get raise/fall time
2670  * @regulator: regulator source
2671  * @old_uV: starting voltage in microvolts
2672  * @new_uV: target voltage in microvolts
2673  *
2674  * Provided with the starting and ending voltage, this function attempts to
2675  * calculate the time in microseconds required to rise or fall to this new
2676  * voltage.
2677  */
2678 int regulator_set_voltage_time(struct regulator *regulator,
2679                                int old_uV, int new_uV)
2680 {
2681         struct regulator_dev *rdev = regulator->rdev;
2682         const struct regulator_ops *ops = rdev->desc->ops;
2683         int old_sel = -1;
2684         int new_sel = -1;
2685         int voltage;
2686         int i;
2687
2688         /* Currently requires operations to do this */
2689         if (!ops->list_voltage || !ops->set_voltage_time_sel
2690             || !rdev->desc->n_voltages)
2691                 return -EINVAL;
2692
2693         for (i = 0; i < rdev->desc->n_voltages; i++) {
2694                 /* We only look for exact voltage matches here */
2695                 voltage = regulator_list_voltage(regulator, i);
2696                 if (voltage < 0)
2697                         return -EINVAL;
2698                 if (voltage == 0)
2699                         continue;
2700                 if (voltage == old_uV)
2701                         old_sel = i;
2702                 if (voltage == new_uV)
2703                         new_sel = i;
2704         }
2705
2706         if (old_sel < 0 || new_sel < 0)
2707                 return -EINVAL;
2708
2709         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
2710 }
2711 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
2712
2713 /**
2714  * regulator_set_voltage_time_sel - get raise/fall time
2715  * @rdev: regulator source device
2716  * @old_selector: selector for starting voltage
2717  * @new_selector: selector for target voltage
2718  *
2719  * Provided with the starting and target voltage selectors, this function
2720  * returns time in microseconds required to rise or fall to this new voltage
2721  *
2722  * Drivers providing ramp_delay in regulation_constraints can use this as their
2723  * set_voltage_time_sel() operation.
2724  */
2725 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
2726                                    unsigned int old_selector,
2727                                    unsigned int new_selector)
2728 {
2729         unsigned int ramp_delay = 0;
2730         int old_volt, new_volt;
2731
2732         if (rdev->constraints->ramp_delay)
2733                 ramp_delay = rdev->constraints->ramp_delay;
2734         else if (rdev->desc->ramp_delay)
2735                 ramp_delay = rdev->desc->ramp_delay;
2736
2737         if (ramp_delay == 0) {
2738                 rdev_warn(rdev, "ramp_delay not set\n");
2739                 return 0;
2740         }
2741
2742         /* sanity check */
2743         if (!rdev->desc->ops->list_voltage)
2744                 return -EINVAL;
2745
2746         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
2747         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
2748
2749         return DIV_ROUND_UP(abs(new_volt - old_volt), ramp_delay);
2750 }
2751 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
2752
2753 /**
2754  * regulator_sync_voltage - re-apply last regulator output voltage
2755  * @regulator: regulator source
2756  *
2757  * Re-apply the last configured voltage.  This is intended to be used
2758  * where some external control source the consumer is cooperating with
2759  * has caused the configured voltage to change.
2760  */
2761 int regulator_sync_voltage(struct regulator *regulator)
2762 {
2763         struct regulator_dev *rdev = regulator->rdev;
2764         int ret, min_uV, max_uV;
2765
2766         mutex_lock(&rdev->mutex);
2767
2768         if (!rdev->desc->ops->set_voltage &&
2769             !rdev->desc->ops->set_voltage_sel) {
2770                 ret = -EINVAL;
2771                 goto out;
2772         }
2773
2774         /* This is only going to work if we've had a voltage configured. */
2775         if (!regulator->min_uV && !regulator->max_uV) {
2776                 ret = -EINVAL;
2777                 goto out;
2778         }
2779
2780         min_uV = regulator->min_uV;
2781         max_uV = regulator->max_uV;
2782
2783         /* This should be a paranoia check... */
2784         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
2785         if (ret < 0)
2786                 goto out;
2787
2788         ret = regulator_check_consumers(rdev, &min_uV, &max_uV);
2789         if (ret < 0)
2790                 goto out;
2791
2792         ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
2793
2794 out:
2795         mutex_unlock(&rdev->mutex);
2796         return ret;
2797 }
2798 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
2799
2800 static int _regulator_get_voltage(struct regulator_dev *rdev)
2801 {
2802         int sel, ret;
2803
2804         if (rdev->desc->ops->get_voltage_sel) {
2805                 sel = rdev->desc->ops->get_voltage_sel(rdev);
2806                 if (sel < 0)
2807                         return sel;
2808                 ret = rdev->desc->ops->list_voltage(rdev, sel);
2809         } else if (rdev->desc->ops->get_voltage) {
2810                 ret = rdev->desc->ops->get_voltage(rdev);
2811         } else if (rdev->desc->ops->list_voltage) {
2812                 ret = rdev->desc->ops->list_voltage(rdev, 0);
2813         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
2814                 ret = rdev->desc->fixed_uV;
2815         } else if (rdev->supply) {
2816                 ret = regulator_get_voltage(rdev->supply);
2817         } else {
2818                 return -EINVAL;
2819         }
2820
2821         if (ret < 0)
2822                 return ret;
2823         return ret - rdev->constraints->uV_offset;
2824 }
2825
2826 /**
2827  * regulator_get_voltage - get regulator output voltage
2828  * @regulator: regulator source
2829  *
2830  * This returns the current regulator voltage in uV.
2831  *
2832  * NOTE: If the regulator is disabled it will return the voltage value. This
2833  * function should not be used to determine regulator state.
2834  */
2835 int regulator_get_voltage(struct regulator *regulator)
2836 {
2837         int ret;
2838
2839         mutex_lock(&regulator->rdev->mutex);
2840
2841         ret = _regulator_get_voltage(regulator->rdev);
2842
2843         mutex_unlock(&regulator->rdev->mutex);
2844
2845         return ret;
2846 }
2847 EXPORT_SYMBOL_GPL(regulator_get_voltage);
2848
2849 /**
2850  * regulator_set_current_limit - set regulator output current limit
2851  * @regulator: regulator source
2852  * @min_uA: Minimum supported current in uA
2853  * @max_uA: Maximum supported current in uA
2854  *
2855  * Sets current sink to the desired output current. This can be set during
2856  * any regulator state. IOW, regulator can be disabled or enabled.
2857  *
2858  * If the regulator is enabled then the current will change to the new value
2859  * immediately otherwise if the regulator is disabled the regulator will
2860  * output at the new current when enabled.
2861  *
2862  * NOTE: Regulator system constraints must be set for this regulator before
2863  * calling this function otherwise this call will fail.
2864  */
2865 int regulator_set_current_limit(struct regulator *regulator,
2866                                int min_uA, int max_uA)
2867 {
2868         struct regulator_dev *rdev = regulator->rdev;
2869         int ret;
2870
2871         mutex_lock(&rdev->mutex);
2872
2873         /* sanity check */
2874         if (!rdev->desc->ops->set_current_limit) {
2875                 ret = -EINVAL;
2876                 goto out;
2877         }
2878
2879         /* constraints check */
2880         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
2881         if (ret < 0)
2882                 goto out;
2883
2884         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
2885 out:
2886         mutex_unlock(&rdev->mutex);
2887         return ret;
2888 }
2889 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
2890
2891 static int _regulator_get_current_limit(struct regulator_dev *rdev)
2892 {
2893         int ret;
2894
2895         mutex_lock(&rdev->mutex);
2896
2897         /* sanity check */
2898         if (!rdev->desc->ops->get_current_limit) {
2899                 ret = -EINVAL;
2900                 goto out;
2901         }
2902
2903         ret = rdev->desc->ops->get_current_limit(rdev);
2904 out:
2905         mutex_unlock(&rdev->mutex);
2906         return ret;
2907 }
2908
2909 /**
2910  * regulator_get_current_limit - get regulator output current
2911  * @regulator: regulator source
2912  *
2913  * This returns the current supplied by the specified current sink in uA.
2914  *
2915  * NOTE: If the regulator is disabled it will return the current value. This
2916  * function should not be used to determine regulator state.
2917  */
2918 int regulator_get_current_limit(struct regulator *regulator)
2919 {
2920         return _regulator_get_current_limit(regulator->rdev);
2921 }
2922 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
2923
2924 /**
2925  * regulator_set_mode - set regulator operating mode
2926  * @regulator: regulator source
2927  * @mode: operating mode - one of the REGULATOR_MODE constants
2928  *
2929  * Set regulator operating mode to increase regulator efficiency or improve
2930  * regulation performance.
2931  *
2932  * NOTE: Regulator system constraints must be set for this regulator before
2933  * calling this function otherwise this call will fail.
2934  */
2935 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
2936 {
2937         struct regulator_dev *rdev = regulator->rdev;
2938         int ret;
2939         int regulator_curr_mode;
2940
2941         mutex_lock(&rdev->mutex);
2942
2943         /* sanity check */
2944         if (!rdev->desc->ops->set_mode) {
2945                 ret = -EINVAL;
2946                 goto out;
2947         }
2948
2949         /* return if the same mode is requested */
2950         if (rdev->desc->ops->get_mode) {
2951                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
2952                 if (regulator_curr_mode == mode) {
2953                         ret = 0;
2954                         goto out;
2955                 }
2956         }
2957
2958         /* constraints check */
2959         ret = regulator_mode_constrain(rdev, &mode);
2960         if (ret < 0)
2961                 goto out;
2962
2963         ret = rdev->desc->ops->set_mode(rdev, mode);
2964 out:
2965         mutex_unlock(&rdev->mutex);
2966         return ret;
2967 }
2968 EXPORT_SYMBOL_GPL(regulator_set_mode);
2969
2970 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
2971 {
2972         int ret;
2973
2974         mutex_lock(&rdev->mutex);
2975
2976         /* sanity check */
2977         if (!rdev->desc->ops->get_mode) {
2978                 ret = -EINVAL;
2979                 goto out;
2980         }
2981
2982         ret = rdev->desc->ops->get_mode(rdev);
2983 out:
2984         mutex_unlock(&rdev->mutex);
2985         return ret;
2986 }
2987
2988 /**
2989  * regulator_get_mode - get regulator operating mode
2990  * @regulator: regulator source
2991  *
2992  * Get the current regulator operating mode.
2993  */
2994 unsigned int regulator_get_mode(struct regulator *regulator)
2995 {
2996         return _regulator_get_mode(regulator->rdev);
2997 }
2998 EXPORT_SYMBOL_GPL(regulator_get_mode);
2999
3000 /**
3001  * regulator_set_optimum_mode - set regulator optimum operating mode
3002  * @regulator: regulator source
3003  * @uA_load: load current
3004  *
3005  * Notifies the regulator core of a new device load. This is then used by
3006  * DRMS (if enabled by constraints) to set the most efficient regulator
3007  * operating mode for the new regulator loading.
3008  *
3009  * Consumer devices notify their supply regulator of the maximum power
3010  * they will require (can be taken from device datasheet in the power
3011  * consumption tables) when they change operational status and hence power
3012  * state. Examples of operational state changes that can affect power
3013  * consumption are :-
3014  *
3015  *    o Device is opened / closed.
3016  *    o Device I/O is about to begin or has just finished.
3017  *    o Device is idling in between work.
3018  *
3019  * This information is also exported via sysfs to userspace.
3020  *
3021  * DRMS will sum the total requested load on the regulator and change
3022  * to the most efficient operating mode if platform constraints allow.
3023  *
3024  * Returns the new regulator mode or error.
3025  */
3026 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
3027 {
3028         struct regulator_dev *rdev = regulator->rdev;
3029         int ret;
3030
3031         mutex_lock(&rdev->mutex);
3032         regulator->uA_load = uA_load;
3033         ret = drms_uA_update(rdev);
3034         mutex_unlock(&rdev->mutex);
3035
3036         return ret;
3037 }
3038 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
3039
3040 /**
3041  * regulator_allow_bypass - allow the regulator to go into bypass mode
3042  *
3043  * @regulator: Regulator to configure
3044  * @enable: enable or disable bypass mode
3045  *
3046  * Allow the regulator to go into bypass mode if all other consumers
3047  * for the regulator also enable bypass mode and the machine
3048  * constraints allow this.  Bypass mode means that the regulator is
3049  * simply passing the input directly to the output with no regulation.
3050  */
3051 int regulator_allow_bypass(struct regulator *regulator, bool enable)
3052 {
3053         struct regulator_dev *rdev = regulator->rdev;
3054         int ret = 0;
3055
3056         if (!rdev->desc->ops->set_bypass)
3057                 return 0;
3058
3059         if (rdev->constraints &&
3060             !(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_BYPASS))
3061                 return 0;
3062
3063         mutex_lock(&rdev->mutex);
3064
3065         if (enable && !regulator->bypass) {
3066                 rdev->bypass_count++;
3067
3068                 if (rdev->bypass_count == rdev->open_count) {
3069                         ret = rdev->desc->ops->set_bypass(rdev, enable);
3070                         if (ret != 0)
3071                                 rdev->bypass_count--;
3072                 }
3073
3074         } else if (!enable && regulator->bypass) {
3075                 rdev->bypass_count--;
3076
3077                 if (rdev->bypass_count != rdev->open_count) {
3078                         ret = rdev->desc->ops->set_bypass(rdev, enable);
3079                         if (ret != 0)
3080                                 rdev->bypass_count++;
3081                 }
3082         }
3083
3084         if (ret == 0)
3085                 regulator->bypass = enable;
3086
3087         mutex_unlock(&rdev->mutex);
3088
3089         return ret;
3090 }
3091 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
3092
3093 /**
3094  * regulator_register_notifier - register regulator event notifier
3095  * @regulator: regulator source
3096  * @nb: notifier block
3097  *
3098  * Register notifier block to receive regulator events.
3099  */
3100 int regulator_register_notifier(struct regulator *regulator,
3101                               struct notifier_block *nb)
3102 {
3103         return blocking_notifier_chain_register(&regulator->rdev->notifier,
3104                                                 nb);
3105 }
3106 EXPORT_SYMBOL_GPL(regulator_register_notifier);
3107
3108 /**
3109  * regulator_unregister_notifier - unregister regulator event notifier
3110  * @regulator: regulator source
3111  * @nb: notifier block
3112  *
3113  * Unregister regulator event notifier block.
3114  */
3115 int regulator_unregister_notifier(struct regulator *regulator,
3116                                 struct notifier_block *nb)
3117 {
3118         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
3119                                                   nb);
3120 }
3121 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
3122
3123 /* notify regulator consumers and downstream regulator consumers.
3124  * Note mutex must be held by caller.
3125  */
3126 static int _notifier_call_chain(struct regulator_dev *rdev,
3127                                   unsigned long event, void *data)
3128 {
3129         /* call rdev chain first */
3130         return blocking_notifier_call_chain(&rdev->notifier, event, data);
3131 }
3132
3133 /**
3134  * regulator_bulk_get - get multiple regulator consumers
3135  *
3136  * @dev:           Device to supply
3137  * @num_consumers: Number of consumers to register
3138  * @consumers:     Configuration of consumers; clients are stored here.
3139  *
3140  * @return 0 on success, an errno on failure.
3141  *
3142  * This helper function allows drivers to get several regulator
3143  * consumers in one operation.  If any of the regulators cannot be
3144  * acquired then any regulators that were allocated will be freed
3145  * before returning to the caller.
3146  */
3147 int regulator_bulk_get(struct device *dev, int num_consumers,
3148                        struct regulator_bulk_data *consumers)
3149 {
3150         int i;
3151         int ret;
3152
3153         for (i = 0; i < num_consumers; i++)
3154                 consumers[i].consumer = NULL;
3155
3156         for (i = 0; i < num_consumers; i++) {
3157                 consumers[i].consumer = regulator_get(dev,
3158                                                       consumers[i].supply);
3159                 if (IS_ERR(consumers[i].consumer)) {
3160                         ret = PTR_ERR(consumers[i].consumer);
3161                         dev_err(dev, "Failed to get supply '%s': %d\n",
3162                                 consumers[i].supply, ret);
3163                         consumers[i].consumer = NULL;
3164                         goto err;
3165                 }
3166         }
3167
3168         return 0;
3169
3170 err:
3171         while (--i >= 0)
3172                 regulator_put(consumers[i].consumer);
3173
3174         return ret;
3175 }
3176 EXPORT_SYMBOL_GPL(regulator_bulk_get);
3177
3178 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
3179 {
3180         struct regulator_bulk_data *bulk = data;
3181
3182         bulk->ret = regulator_enable(bulk->consumer);
3183 }
3184
3185 /**
3186  * regulator_bulk_enable - enable multiple regulator consumers
3187  *
3188  * @num_consumers: Number of consumers
3189  * @consumers:     Consumer data; clients are stored here.
3190  * @return         0 on success, an errno on failure
3191  *
3192  * This convenience API allows consumers to enable multiple regulator
3193  * clients in a single API call.  If any consumers cannot be enabled
3194  * then any others that were enabled will be disabled again prior to
3195  * return.
3196  */
3197 int regulator_bulk_enable(int num_consumers,
3198                           struct regulator_bulk_data *consumers)
3199 {
3200         ASYNC_DOMAIN_EXCLUSIVE(async_domain);
3201         int i;
3202         int ret = 0;
3203
3204         for (i = 0; i < num_consumers; i++) {
3205                 if (consumers[i].consumer->always_on)
3206                         consumers[i].ret = 0;
3207                 else
3208                         async_schedule_domain(regulator_bulk_enable_async,
3209                                               &consumers[i], &async_domain);
3210         }
3211
3212         async_synchronize_full_domain(&async_domain);
3213
3214         /* If any consumer failed we need to unwind any that succeeded */
3215         for (i = 0; i < num_consumers; i++) {
3216                 if (consumers[i].ret != 0) {
3217                         ret = consumers[i].ret;
3218                         goto err;
3219                 }
3220         }
3221
3222         return 0;
3223
3224 err:
3225         for (i = 0; i < num_consumers; i++) {
3226                 if (consumers[i].ret < 0)
3227                         pr_err("Failed to enable %s: %d\n", consumers[i].supply,
3228                                consumers[i].ret);
3229                 else
3230                         regulator_disable(consumers[i].consumer);
3231         }
3232
3233         return ret;
3234 }
3235 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
3236
3237 /**
3238  * regulator_bulk_disable - disable multiple regulator consumers
3239  *
3240  * @num_consumers: Number of consumers
3241  * @consumers:     Consumer data; clients are stored here.
3242  * @return         0 on success, an errno on failure
3243  *
3244  * This convenience API allows consumers to disable multiple regulator
3245  * clients in a single API call.  If any consumers cannot be disabled
3246  * then any others that were disabled will be enabled again prior to
3247  * return.
3248  */
3249 int regulator_bulk_disable(int num_consumers,
3250                            struct regulator_bulk_data *consumers)
3251 {
3252         int i;
3253         int ret, r;
3254
3255         for (i = num_consumers - 1; i >= 0; --i) {
3256                 ret = regulator_disable(consumers[i].consumer);
3257                 if (ret != 0)
3258                         goto err;
3259         }
3260
3261         return 0;
3262
3263 err:
3264         pr_err("Failed to disable %s: %d\n", consumers[i].supply, ret);
3265         for (++i; i < num_consumers; ++i) {
3266                 r = regulator_enable(consumers[i].consumer);
3267                 if (r != 0)
3268                         pr_err("Failed to reename %s: %d\n",
3269                                consumers[i].supply, r);
3270         }
3271
3272         return ret;
3273 }
3274 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
3275
3276 /**
3277  * regulator_bulk_force_disable - force disable multiple regulator consumers
3278  *
3279  * @num_consumers: Number of consumers
3280  * @consumers:     Consumer data; clients are stored here.
3281  * @return         0 on success, an errno on failure
3282  *
3283  * This convenience API allows consumers to forcibly disable multiple regulator
3284  * clients in a single API call.
3285  * NOTE: This should be used for situations when device damage will
3286  * likely occur if the regulators are not disabled (e.g. over temp).
3287  * Although regulator_force_disable function call for some consumers can
3288  * return error numbers, the function is called for all consumers.
3289  */
3290 int regulator_bulk_force_disable(int num_consumers,
3291                            struct regulator_bulk_data *consumers)
3292 {
3293         int i;
3294         int ret;
3295
3296         for (i = 0; i < num_consumers; i++)
3297                 consumers[i].ret =
3298                             regulator_force_disable(consumers[i].consumer);
3299
3300         for (i = 0; i < num_consumers; i++) {
3301                 if (consumers[i].ret != 0) {
3302                         ret = consumers[i].ret;
3303                         goto out;
3304                 }
3305         }
3306
3307         return 0;
3308 out:
3309         return ret;
3310 }
3311 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
3312
3313 /**
3314  * regulator_bulk_free - free multiple regulator consumers
3315  *
3316  * @num_consumers: Number of consumers
3317  * @consumers:     Consumer data; clients are stored here.
3318  *
3319  * This convenience API allows consumers to free multiple regulator
3320  * clients in a single API call.
3321  */
3322 void regulator_bulk_free(int num_consumers,
3323                          struct regulator_bulk_data *consumers)
3324 {
3325         int i;
3326
3327         for (i = 0; i < num_consumers; i++) {
3328                 regulator_put(consumers[i].consumer);
3329                 consumers[i].consumer = NULL;
3330         }
3331 }
3332 EXPORT_SYMBOL_GPL(regulator_bulk_free);
3333
3334 /**
3335  * regulator_notifier_call_chain - call regulator event notifier
3336  * @rdev: regulator source
3337  * @event: notifier block
3338  * @data: callback-specific data.
3339  *
3340  * Called by regulator drivers to notify clients a regulator event has
3341  * occurred. We also notify regulator clients downstream.
3342  * Note lock must be held by caller.
3343  */
3344 int regulator_notifier_call_chain(struct regulator_dev *rdev,
3345                                   unsigned long event, void *data)
3346 {
3347         _notifier_call_chain(rdev, event, data);
3348         return NOTIFY_DONE;
3349
3350 }
3351 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
3352
3353 /**
3354  * regulator_mode_to_status - convert a regulator mode into a status
3355  *
3356  * @mode: Mode to convert
3357  *
3358  * Convert a regulator mode into a status.
3359  */
3360 int regulator_mode_to_status(unsigned int mode)
3361 {
3362         switch (mode) {
3363         case REGULATOR_MODE_FAST:
3364                 return REGULATOR_STATUS_FAST;
3365         case REGULATOR_MODE_NORMAL:
3366                 return REGULATOR_STATUS_NORMAL;
3367         case REGULATOR_MODE_IDLE:
3368                 return REGULATOR_STATUS_IDLE;
3369         case REGULATOR_MODE_STANDBY:
3370                 return REGULATOR_STATUS_STANDBY;
3371         default:
3372                 return REGULATOR_STATUS_UNDEFINED;
3373         }
3374 }
3375 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
3376
3377 static struct attribute *regulator_dev_attrs[] = {
3378         &dev_attr_name.attr,
3379         &dev_attr_num_users.attr,
3380         &dev_attr_type.attr,
3381         &dev_attr_microvolts.attr,
3382         &dev_attr_microamps.attr,
3383         &dev_attr_opmode.attr,
3384         &dev_attr_state.attr,
3385         &dev_attr_status.attr,
3386         &dev_attr_bypass.attr,
3387         &dev_attr_requested_microamps.attr,
3388         &dev_attr_min_microvolts.attr,
3389         &dev_attr_max_microvolts.attr,
3390         &dev_attr_min_microamps.attr,
3391         &dev_attr_max_microamps.attr,
3392         &dev_attr_suspend_standby_state.attr,
3393         &dev_attr_suspend_mem_state.attr,
3394         &dev_attr_suspend_disk_state.attr,
3395         &dev_attr_suspend_standby_microvolts.attr,
3396         &dev_attr_suspend_mem_microvolts.attr,
3397         &dev_attr_suspend_disk_microvolts.attr,
3398         &dev_attr_suspend_standby_mode.attr,
3399         &dev_attr_suspend_mem_mode.attr,
3400         &dev_attr_suspend_disk_mode.attr,
3401         NULL
3402 };
3403
3404 /*
3405  * To avoid cluttering sysfs (and memory) with useless state, only
3406  * create attributes that can be meaningfully displayed.
3407  */
3408 static umode_t regulator_attr_is_visible(struct kobject *kobj,
3409                                          struct attribute *attr, int idx)
3410 {
3411         struct device *dev = kobj_to_dev(kobj);
3412         struct regulator_dev *rdev = container_of(dev, struct regulator_dev, dev);
3413         const struct regulator_ops *ops = rdev->desc->ops;
3414         umode_t mode = attr->mode;
3415
3416         /* these three are always present */
3417         if (attr == &dev_attr_name.attr ||
3418             attr == &dev_attr_num_users.attr ||
3419             attr == &dev_attr_type.attr)
3420                 return mode;
3421
3422         /* some attributes need specific methods to be displayed */
3423         if (attr == &dev_attr_microvolts.attr) {
3424                 if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
3425                     (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
3426                     (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
3427                     (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
3428                         return mode;
3429                 return 0;
3430         }
3431
3432         if (attr == &dev_attr_microamps.attr)
3433                 return ops->get_current_limit ? mode : 0;
3434
3435         if (attr == &dev_attr_opmode.attr)
3436                 return ops->get_mode ? mode : 0;
3437
3438         if (attr == &dev_attr_state.attr)
3439                 return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
3440
3441         if (attr == &dev_attr_status.attr)
3442                 return ops->get_status ? mode : 0;
3443
3444         if (attr == &dev_attr_bypass.attr)
3445                 return ops->get_bypass ? mode : 0;
3446
3447         /* some attributes are type-specific */
3448         if (attr == &dev_attr_requested_microamps.attr)
3449                 return rdev->desc->type == REGULATOR_CURRENT ? mode : 0;
3450
3451         /* all the other attributes exist to support constraints;
3452          * don't show them if there are no constraints, or if the
3453          * relevant supporting methods are missing.
3454          */
3455         if (!rdev->constraints)
3456                 return 0;
3457
3458         /* constraints need specific supporting methods */
3459         if (attr == &dev_attr_min_microvolts.attr ||
3460             attr == &dev_attr_max_microvolts.attr)
3461                 return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
3462
3463         if (attr == &dev_attr_min_microamps.attr ||
3464             attr == &dev_attr_max_microamps.attr)
3465                 return ops->set_current_limit ? mode : 0;
3466
3467         if (attr == &dev_attr_suspend_standby_state.attr ||
3468             attr == &dev_attr_suspend_mem_state.attr ||
3469             attr == &dev_attr_suspend_disk_state.attr)
3470                 return mode;
3471
3472         if (attr == &dev_attr_suspend_standby_microvolts.attr ||
3473             attr == &dev_attr_suspend_mem_microvolts.attr ||
3474             attr == &dev_attr_suspend_disk_microvolts.attr)
3475                 return ops->set_suspend_voltage ? mode : 0;
3476
3477         if (attr == &dev_attr_suspend_standby_mode.attr ||
3478             attr == &dev_attr_suspend_mem_mode.attr ||
3479             attr == &dev_attr_suspend_disk_mode.attr)
3480                 return ops->set_suspend_mode ? mode : 0;
3481
3482         return mode;
3483 }
3484
3485 static const struct attribute_group regulator_dev_group = {
3486         .attrs = regulator_dev_attrs,
3487         .is_visible = regulator_attr_is_visible,
3488 };
3489
3490 static const struct attribute_group *regulator_dev_groups[] = {
3491         &regulator_dev_group,
3492         NULL
3493 };
3494
3495 static void regulator_dev_release(struct device *dev)
3496 {
3497         struct regulator_dev *rdev = dev_get_drvdata(dev);
3498         kfree(rdev);
3499 }
3500
3501 static struct class regulator_class = {
3502         .name = "regulator",
3503         .dev_release = regulator_dev_release,
3504         .dev_groups = regulator_dev_groups,
3505 };
3506
3507 static void rdev_init_debugfs(struct regulator_dev *rdev)
3508 {
3509         rdev->debugfs = debugfs_create_dir(rdev_get_name(rdev), debugfs_root);
3510         if (!rdev->debugfs) {
3511                 rdev_warn(rdev, "Failed to create debugfs directory\n");
3512                 return;
3513         }
3514
3515         debugfs_create_u32("use_count", 0444, rdev->debugfs,
3516                            &rdev->use_count);
3517         debugfs_create_u32("open_count", 0444, rdev->debugfs,
3518                            &rdev->open_count);
3519         debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
3520                            &rdev->bypass_count);
3521 }
3522
3523 /**
3524  * regulator_register - register regulator
3525  * @regulator_desc: regulator to register
3526  * @cfg: runtime configuration for regulator
3527  *
3528  * Called by regulator drivers to register a regulator.
3529  * Returns a valid pointer to struct regulator_dev on success
3530  * or an ERR_PTR() on error.
3531  */
3532 struct regulator_dev *
3533 regulator_register(const struct regulator_desc *regulator_desc,
3534                    const struct regulator_config *cfg)
3535 {
3536         const struct regulation_constraints *constraints = NULL;
3537         const struct regulator_init_data *init_data;
3538         struct regulator_config *config = NULL;
3539         static atomic_t regulator_no = ATOMIC_INIT(-1);
3540         struct regulator_dev *rdev;
3541         struct device *dev;
3542         int ret, i;
3543         const char *supply = NULL;
3544
3545         if (regulator_desc == NULL || cfg == NULL)
3546                 return ERR_PTR(-EINVAL);
3547
3548         dev = cfg->dev;
3549         WARN_ON(!dev);
3550
3551         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
3552                 return ERR_PTR(-EINVAL);
3553
3554         if (regulator_desc->type != REGULATOR_VOLTAGE &&
3555             regulator_desc->type != REGULATOR_CURRENT)
3556                 return ERR_PTR(-EINVAL);
3557
3558         /* Only one of each should be implemented */
3559         WARN_ON(regulator_desc->ops->get_voltage &&
3560                 regulator_desc->ops->get_voltage_sel);
3561         WARN_ON(regulator_desc->ops->set_voltage &&
3562                 regulator_desc->ops->set_voltage_sel);
3563
3564         /* If we're using selectors we must implement list_voltage. */
3565         if (regulator_desc->ops->get_voltage_sel &&
3566             !regulator_desc->ops->list_voltage) {
3567                 return ERR_PTR(-EINVAL);
3568         }
3569         if (regulator_desc->ops->set_voltage_sel &&
3570             !regulator_desc->ops->list_voltage) {
3571                 return ERR_PTR(-EINVAL);
3572         }
3573
3574         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
3575         if (rdev == NULL)
3576                 return ERR_PTR(-ENOMEM);
3577
3578         /*
3579          * Duplicate the config so the driver could override it after
3580          * parsing init data.
3581          */
3582         config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
3583         if (config == NULL) {
3584                 kfree(rdev);
3585                 return ERR_PTR(-ENOMEM);
3586         }
3587
3588         init_data = regulator_of_get_init_data(dev, regulator_desc, config,
3589                                                &rdev->dev.of_node);
3590         if (!init_data) {
3591                 init_data = config->init_data;
3592                 rdev->dev.of_node = of_node_get(config->of_node);
3593         }
3594
3595         mutex_lock(&regulator_list_mutex);
3596
3597         mutex_init(&rdev->mutex);
3598         rdev->reg_data = config->driver_data;
3599         rdev->owner = regulator_desc->owner;
3600         rdev->desc = regulator_desc;
3601         if (config->regmap)
3602                 rdev->regmap = config->regmap;
3603         else if (dev_get_regmap(dev, NULL))
3604                 rdev->regmap = dev_get_regmap(dev, NULL);
3605         else if (dev->parent)
3606                 rdev->regmap = dev_get_regmap(dev->parent, NULL);
3607         INIT_LIST_HEAD(&rdev->consumer_list);
3608         INIT_LIST_HEAD(&rdev->list);
3609         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
3610         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
3611
3612         /* preform any regulator specific init */
3613         if (init_data && init_data->regulator_init) {
3614                 ret = init_data->regulator_init(rdev->reg_data);
3615                 if (ret < 0)
3616                         goto clean;
3617         }
3618
3619         /* register with sysfs */
3620         rdev->dev.class = &regulator_class;
3621         rdev->dev.parent = dev;
3622         dev_set_name(&rdev->dev, "regulator.%lu",
3623                     (unsigned long) atomic_inc_return(&regulator_no));
3624         ret = device_register(&rdev->dev);
3625         if (ret != 0) {
3626                 put_device(&rdev->dev);
3627                 goto clean;
3628         }
3629
3630         dev_set_drvdata(&rdev->dev, rdev);
3631
3632         if ((config->ena_gpio || config->ena_gpio_initialized) &&
3633             gpio_is_valid(config->ena_gpio)) {
3634                 ret = regulator_ena_gpio_request(rdev, config);
3635                 if (ret != 0) {
3636                         rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
3637                                  config->ena_gpio, ret);
3638                         goto wash;
3639                 }
3640         }
3641
3642         /* set regulator constraints */
3643         if (init_data)
3644                 constraints = &init_data->constraints;
3645
3646         ret = set_machine_constraints(rdev, constraints);
3647         if (ret < 0)
3648                 goto scrub;
3649
3650         if (init_data && init_data->supply_regulator)
3651                 supply = init_data->supply_regulator;
3652         else if (regulator_desc->supply_name)
3653                 supply = regulator_desc->supply_name;
3654
3655         if (supply) {
3656                 struct regulator_dev *r;
3657
3658                 r = regulator_dev_lookup(dev, supply, &ret);
3659
3660                 if (ret == -ENODEV) {
3661                         /*
3662                          * No supply was specified for this regulator and
3663                          * there will never be one.
3664                          */
3665                         ret = 0;
3666                         goto add_dev;
3667                 } else if (!r) {
3668                         dev_err(dev, "Failed to find supply %s\n", supply);
3669                         ret = -EPROBE_DEFER;
3670                         goto scrub;
3671                 }
3672
3673                 ret = set_supply(rdev, r);
3674                 if (ret < 0)
3675                         goto scrub;
3676
3677                 /* Enable supply if rail is enabled */
3678                 if (_regulator_is_enabled(rdev)) {
3679                         ret = regulator_enable(rdev->supply);
3680                         if (ret < 0)
3681                                 goto scrub;
3682                 }
3683         }
3684
3685 add_dev:
3686         /* add consumers devices */
3687         if (init_data) {
3688                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
3689                         ret = set_consumer_device_supply(rdev,
3690                                 init_data->consumer_supplies[i].dev_name,
3691                                 init_data->consumer_supplies[i].supply);
3692                         if (ret < 0) {
3693                                 dev_err(dev, "Failed to set supply %s\n",
3694                                         init_data->consumer_supplies[i].supply);
3695                                 goto unset_supplies;
3696                         }
3697                 }
3698         }
3699
3700         list_add(&rdev->list, &regulator_list);
3701
3702         rdev_init_debugfs(rdev);
3703 out:
3704         mutex_unlock(&regulator_list_mutex);
3705         kfree(config);
3706         return rdev;
3707
3708 unset_supplies:
3709         unset_regulator_supplies(rdev);
3710
3711 scrub:
3712         if (rdev->supply)
3713                 _regulator_put(rdev->supply);
3714         regulator_ena_gpio_free(rdev);
3715         kfree(rdev->constraints);
3716 wash:
3717         device_unregister(&rdev->dev);
3718         /* device core frees rdev */
3719         rdev = ERR_PTR(ret);
3720         goto out;
3721
3722 clean:
3723         kfree(rdev);
3724         rdev = ERR_PTR(ret);
3725         goto out;
3726 }
3727 EXPORT_SYMBOL_GPL(regulator_register);
3728
3729 /**
3730  * regulator_unregister - unregister regulator
3731  * @rdev: regulator to unregister
3732  *
3733  * Called by regulator drivers to unregister a regulator.
3734  */
3735 void regulator_unregister(struct regulator_dev *rdev)
3736 {
3737         if (rdev == NULL)
3738                 return;
3739
3740         if (rdev->supply) {
3741                 while (rdev->use_count--)
3742                         regulator_disable(rdev->supply);
3743                 regulator_put(rdev->supply);
3744         }
3745         mutex_lock(&regulator_list_mutex);
3746         debugfs_remove_recursive(rdev->debugfs);
3747         flush_work(&rdev->disable_work.work);
3748         WARN_ON(rdev->open_count);
3749         unset_regulator_supplies(rdev);
3750         list_del(&rdev->list);
3751         kfree(rdev->constraints);
3752         regulator_ena_gpio_free(rdev);
3753         of_node_put(rdev->dev.of_node);
3754         device_unregister(&rdev->dev);
3755         mutex_unlock(&regulator_list_mutex);
3756 }
3757 EXPORT_SYMBOL_GPL(regulator_unregister);
3758
3759 /**
3760  * regulator_suspend_prepare - prepare regulators for system wide suspend
3761  * @state: system suspend state
3762  *
3763  * Configure each regulator with it's suspend operating parameters for state.
3764  * This will usually be called by machine suspend code prior to supending.
3765  */
3766 int regulator_suspend_prepare(suspend_state_t state)
3767 {
3768         struct regulator_dev *rdev;
3769         int ret = 0;
3770
3771         /* ON is handled by regulator active state */
3772         if (state == PM_SUSPEND_ON)
3773                 return -EINVAL;
3774
3775         mutex_lock(&regulator_list_mutex);
3776         list_for_each_entry(rdev, &regulator_list, list) {
3777
3778                 mutex_lock(&rdev->mutex);
3779                 ret = suspend_prepare(rdev, state);
3780                 mutex_unlock(&rdev->mutex);
3781
3782                 if (ret < 0) {
3783                         rdev_err(rdev, "failed to prepare\n");
3784                         goto out;
3785                 }
3786         }
3787 out:
3788         mutex_unlock(&regulator_list_mutex);
3789         return ret;
3790 }
3791 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
3792
3793 /**
3794  * regulator_suspend_finish - resume regulators from system wide suspend
3795  *
3796  * Turn on regulators that might be turned off by regulator_suspend_prepare
3797  * and that should be turned on according to the regulators properties.
3798  */
3799 int regulator_suspend_finish(void)
3800 {
3801         struct regulator_dev *rdev;
3802         int ret = 0, error;
3803
3804         mutex_lock(&regulator_list_mutex);
3805         list_for_each_entry(rdev, &regulator_list, list) {
3806                 mutex_lock(&rdev->mutex);
3807                 if (rdev->use_count > 0  || rdev->constraints->always_on) {
3808                         if (!_regulator_is_enabled(rdev)) {
3809                                 error = _regulator_do_enable(rdev);
3810                                 if (error)
3811                                         ret = error;
3812                         }
3813                 } else {
3814                         if (!have_full_constraints())
3815                                 goto unlock;
3816                         if (!_regulator_is_enabled(rdev))
3817                                 goto unlock;
3818
3819                         error = _regulator_do_disable(rdev);
3820                         if (error)
3821                                 ret = error;
3822                 }
3823 unlock:
3824                 mutex_unlock(&rdev->mutex);
3825         }
3826         mutex_unlock(&regulator_list_mutex);
3827         return ret;
3828 }
3829 EXPORT_SYMBOL_GPL(regulator_suspend_finish);
3830
3831 /**
3832  * regulator_has_full_constraints - the system has fully specified constraints
3833  *
3834  * Calling this function will cause the regulator API to disable all
3835  * regulators which have a zero use count and don't have an always_on
3836  * constraint in a late_initcall.
3837  *
3838  * The intention is that this will become the default behaviour in a
3839  * future kernel release so users are encouraged to use this facility
3840  * now.
3841  */
3842 void regulator_has_full_constraints(void)
3843 {
3844         has_full_constraints = 1;
3845 }
3846 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
3847
3848 /**
3849  * rdev_get_drvdata - get rdev regulator driver data
3850  * @rdev: regulator
3851  *
3852  * Get rdev regulator driver private data. This call can be used in the
3853  * regulator driver context.
3854  */
3855 void *rdev_get_drvdata(struct regulator_dev *rdev)
3856 {
3857         return rdev->reg_data;
3858 }
3859 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
3860
3861 /**
3862  * regulator_get_drvdata - get regulator driver data
3863  * @regulator: regulator
3864  *
3865  * Get regulator driver private data. This call can be used in the consumer
3866  * driver context when non API regulator specific functions need to be called.
3867  */
3868 void *regulator_get_drvdata(struct regulator *regulator)
3869 {
3870         return regulator->rdev->reg_data;
3871 }
3872 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
3873
3874 /**
3875  * regulator_set_drvdata - set regulator driver data
3876  * @regulator: regulator
3877  * @data: data
3878  */
3879 void regulator_set_drvdata(struct regulator *regulator, void *data)
3880 {
3881         regulator->rdev->reg_data = data;
3882 }
3883 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
3884
3885 /**
3886  * regulator_get_id - get regulator ID
3887  * @rdev: regulator
3888  */
3889 int rdev_get_id(struct regulator_dev *rdev)
3890 {
3891         return rdev->desc->id;
3892 }
3893 EXPORT_SYMBOL_GPL(rdev_get_id);
3894
3895 struct device *rdev_get_dev(struct regulator_dev *rdev)
3896 {
3897         return &rdev->dev;
3898 }
3899 EXPORT_SYMBOL_GPL(rdev_get_dev);
3900
3901 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
3902 {
3903         return reg_init_data->driver_data;
3904 }
3905 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
3906
3907 #ifdef CONFIG_DEBUG_FS
3908 static ssize_t supply_map_read_file(struct file *file, char __user *user_buf,
3909                                     size_t count, loff_t *ppos)
3910 {
3911         char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
3912         ssize_t len, ret = 0;
3913         struct regulator_map *map;
3914
3915         if (!buf)
3916                 return -ENOMEM;
3917
3918         list_for_each_entry(map, &regulator_map_list, list) {
3919                 len = snprintf(buf + ret, PAGE_SIZE - ret,
3920                                "%s -> %s.%s\n",
3921                                rdev_get_name(map->regulator), map->dev_name,
3922                                map->supply);
3923                 if (len >= 0)
3924                         ret += len;
3925                 if (ret > PAGE_SIZE) {
3926                         ret = PAGE_SIZE;
3927                         break;
3928                 }
3929         }
3930
3931         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
3932
3933         kfree(buf);
3934
3935         return ret;
3936 }
3937 #endif
3938
3939 static const struct file_operations supply_map_fops = {
3940 #ifdef CONFIG_DEBUG_FS
3941         .read = supply_map_read_file,
3942         .llseek = default_llseek,
3943 #endif
3944 };
3945
3946 static int __init regulator_init(void)
3947 {
3948         int ret;
3949
3950         ret = class_register(&regulator_class);
3951
3952         debugfs_root = debugfs_create_dir("regulator", NULL);
3953         if (!debugfs_root)
3954                 pr_warn("regulator: Failed to create debugfs directory\n");
3955
3956         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
3957                             &supply_map_fops);
3958
3959         regulator_dummy_init();
3960
3961         return ret;
3962 }
3963
3964 /* init early to allow our consumers to complete system booting */
3965 core_initcall(regulator_init);
3966
3967 static int __init regulator_init_complete(void)
3968 {
3969         struct regulator_dev *rdev;
3970         const struct regulator_ops *ops;
3971         struct regulation_constraints *c;
3972         int enabled, ret;
3973
3974         /*
3975          * Since DT doesn't provide an idiomatic mechanism for
3976          * enabling full constraints and since it's much more natural
3977          * with DT to provide them just assume that a DT enabled
3978          * system has full constraints.
3979          */
3980         if (of_have_populated_dt())
3981                 has_full_constraints = true;
3982
3983         mutex_lock(&regulator_list_mutex);
3984
3985         /* If we have a full configuration then disable any regulators
3986          * we have permission to change the status for and which are
3987          * not in use or always_on.  This is effectively the default
3988          * for DT and ACPI as they have full constraints.
3989          */
3990         list_for_each_entry(rdev, &regulator_list, list) {
3991                 ops = rdev->desc->ops;
3992                 c = rdev->constraints;
3993
3994                 if (c && c->always_on)
3995                         continue;
3996
3997                 if (c && !(c->valid_ops_mask & REGULATOR_CHANGE_STATUS))
3998                         continue;
3999
4000                 mutex_lock(&rdev->mutex);
4001
4002                 if (rdev->use_count)
4003                         goto unlock;
4004
4005                 /* If we can't read the status assume it's on. */
4006                 if (ops->is_enabled)
4007                         enabled = ops->is_enabled(rdev);
4008                 else
4009                         enabled = 1;
4010
4011                 if (!enabled)
4012                         goto unlock;
4013
4014                 if (have_full_constraints()) {
4015                         /* We log since this may kill the system if it
4016                          * goes wrong. */
4017                         rdev_info(rdev, "disabling\n");
4018                         ret = _regulator_do_disable(rdev);
4019                         if (ret != 0)
4020                                 rdev_err(rdev, "couldn't disable: %d\n", ret);
4021                 } else {
4022                         /* The intention is that in future we will
4023                          * assume that full constraints are provided
4024                          * so warn even if we aren't going to do
4025                          * anything here.
4026                          */
4027                         rdev_warn(rdev, "incomplete constraints, leaving on\n");
4028                 }
4029
4030 unlock:
4031                 mutex_unlock(&rdev->mutex);
4032         }
4033
4034         mutex_unlock(&regulator_list_mutex);
4035
4036         return 0;
4037 }
4038 late_initcall_sync(regulator_init_complete);