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/device.h>
  19 #include <linux/err.h>
  20 #include <linux/mutex.h>
  21 #include <linux/suspend.h>
  22 #include <linux/delay.h>
  23 #include <linux/regulator/consumer.h>
  24 #include <linux/regulator/driver.h>
  25 #include <linux/regulator/machine.h>
  26
  27 #define REGULATOR_VERSION "0.5"
  28
  29 static DEFINE_MUTEX(regulator_list_mutex);
  30 static LIST_HEAD(regulator_list);
  31 static LIST_HEAD(regulator_map_list);
  32 static int has_full_constraints;
  33
  34 /*
  35  * struct regulator_map
  36  *
  37  * Used to provide symbolic supply names to devices.
  38  */
  39 struct regulator_map {
  40         struct list_head list;
  41         const char *dev_name;   /* The dev_name() for the consumer */
  42         const char *supply;
  43         struct regulator_dev *regulator;
  44 };
  45
  46 /*
  47  * struct regulator
  48  *
  49  * One for each consumer device.
  50  */
  51 struct regulator {
  52         struct device *dev;
  53         struct list_head list;
  54         int uA_load;
  55         int min_uV;
  56         int max_uV;
  57         char *supply_name;
  58         struct device_attribute dev_attr;
  59         struct regulator_dev *rdev;
  60 };
  61
  62 static int _regulator_is_enabled(struct regulator_dev *rdev);
  63 static int _regulator_disable(struct regulator_dev *rdev);
  64 static int _regulator_get_voltage(struct regulator_dev *rdev);
  65 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  66 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  67 static void _notifier_call_chain(struct regulator_dev *rdev,
  68                                   unsigned long event, void *data);
  69
  70 static const char *rdev_get_name(struct regulator_dev *rdev)
  71 {
  72         if (rdev->constraints && rdev->constraints->name)
  73                 return rdev->constraints->name;
  74         else if (rdev->desc->name)
  75                 return rdev->desc->name;
  76         else
  77                 return "";
  78 }
  79
  80 /* gets the regulator for a given consumer device */
  81 static struct regulator *get_device_regulator(struct device *dev)
  82 {
  83         struct regulator *regulator = NULL;
  84         struct regulator_dev *rdev;
  85
  86         mutex_lock(&regulator_list_mutex);
  87         list_for_each_entry(rdev, &regulator_list, list) {
  88                 mutex_lock(&rdev->mutex);
  89                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
  90                         if (regulator->dev == dev) {
  91                                 mutex_unlock(&rdev->mutex);
  92                                 mutex_unlock(&regulator_list_mutex);
  93                                 return regulator;
  94                         }
  95                 }
  96                 mutex_unlock(&rdev->mutex);
  97         }
  98         mutex_unlock(&regulator_list_mutex);
  99         return NULL;
 100 }
 101
 102 /* Platform voltage constraint check */
 103 static int regulator_check_voltage(struct regulator_dev *rdev,
 104                                    int *min_uV, int *max_uV)
 105 {
 106         BUG_ON(*min_uV > *max_uV);
 107
 108         if (!rdev->constraints) {
 109                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 110                        rdev_get_name(rdev));
 111                 return -ENODEV;
 112         }
 113         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 114                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 115                        __func__, rdev_get_name(rdev));
 116                 return -EPERM;
 117         }
 118
 119         if (*max_uV > rdev->constraints->max_uV)
 120                 *max_uV = rdev->constraints->max_uV;
 121         if (*min_uV < rdev->constraints->min_uV)
 122                 *min_uV = rdev->constraints->min_uV;
 123
 124         if (*min_uV > *max_uV)
 125                 return -EINVAL;
 126
 127         return 0;
 128 }
 129
 130 /* current constraint check */
 131 static int regulator_check_current_limit(struct regulator_dev *rdev,
 132                                         int *min_uA, int *max_uA)
 133 {
 134         BUG_ON(*min_uA > *max_uA);
 135
 136         if (!rdev->constraints) {
 137                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 138                        rdev_get_name(rdev));
 139                 return -ENODEV;
 140         }
 141         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 142                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 143                        __func__, rdev_get_name(rdev));
 144                 return -EPERM;
 145         }
 146
 147         if (*max_uA > rdev->constraints->max_uA)
 148                 *max_uA = rdev->constraints->max_uA;
 149         if (*min_uA < rdev->constraints->min_uA)
 150                 *min_uA = rdev->constraints->min_uA;
 151
 152         if (*min_uA > *max_uA)
 153                 return -EINVAL;
 154
 155         return 0;
 156 }
 157
 158 /* operating mode constraint check */
 159 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
 160 {
 161         switch (mode) {
 162         case REGULATOR_MODE_FAST:
 163         case REGULATOR_MODE_NORMAL:
 164         case REGULATOR_MODE_IDLE:
 165         case REGULATOR_MODE_STANDBY:
 166                 break;
 167         default:
 168                 return -EINVAL;
 169         }
 170
 171         if (!rdev->constraints) {
 172                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 173                        rdev_get_name(rdev));
 174                 return -ENODEV;
 175         }
 176         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 177                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 178                        __func__, rdev_get_name(rdev));
 179                 return -EPERM;
 180         }
 181         if (!(rdev->constraints->valid_modes_mask & mode)) {
 182                 printk(KERN_ERR "%s: invalid mode %x for %s\n",
 183                        __func__, mode, rdev_get_name(rdev));
 184                 return -EINVAL;
 185         }
 186         return 0;
 187 }
 188
 189 /* dynamic regulator mode switching constraint check */
 190 static int regulator_check_drms(struct regulator_dev *rdev)
 191 {
 192         if (!rdev->constraints) {
 193                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 194                        rdev_get_name(rdev));
 195                 return -ENODEV;
 196         }
 197         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 198                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 199                        __func__, rdev_get_name(rdev));
 200                 return -EPERM;
 201         }
 202         return 0;
 203 }
 204
 205 static ssize_t device_requested_uA_show(struct device *dev,
 206                              struct device_attribute *attr, char *buf)
 207 {
 208         struct regulator *regulator;
 209
 210         regulator = get_device_regulator(dev);
 211         if (regulator == NULL)
 212                 return 0;
 213
 214         return sprintf(buf, "%d\n", regulator->uA_load);
 215 }
 216
 217 static ssize_t regulator_uV_show(struct device *dev,
 218                                 struct device_attribute *attr, char *buf)
 219 {
 220         struct regulator_dev *rdev = dev_get_drvdata(dev);
 221         ssize_t ret;
 222
 223         mutex_lock(&rdev->mutex);
 224         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 225         mutex_unlock(&rdev->mutex);
 226
 227         return ret;
 228 }
 229 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 230
 231 static ssize_t regulator_uA_show(struct device *dev,
 232                                 struct device_attribute *attr, char *buf)
 233 {
 234         struct regulator_dev *rdev = dev_get_drvdata(dev);
 235
 236         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 237 }
 238 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 239
 240 static ssize_t regulator_name_show(struct device *dev,
 241                              struct device_attribute *attr, char *buf)
 242 {
 243         struct regulator_dev *rdev = dev_get_drvdata(dev);
 244
 245         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 246 }
 247
 248 static ssize_t regulator_print_opmode(char *buf, int mode)
 249 {
 250         switch (mode) {
 251         case REGULATOR_MODE_FAST:
 252                 return sprintf(buf, "fast\n");
 253         case REGULATOR_MODE_NORMAL:
 254                 return sprintf(buf, "normal\n");
 255         case REGULATOR_MODE_IDLE:
 256                 return sprintf(buf, "idle\n");
 257         case REGULATOR_MODE_STANDBY:
 258                 return sprintf(buf, "standby\n");
 259         }
 260         return sprintf(buf, "unknown\n");
 261 }
 262
 263 static ssize_t regulator_opmode_show(struct device *dev,
 264                                     struct device_attribute *attr, char *buf)
 265 {
 266         struct regulator_dev *rdev = dev_get_drvdata(dev);
 267
 268         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 269 }
 270 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 271
 272 static ssize_t regulator_print_state(char *buf, int state)
 273 {
 274         if (state > 0)
 275                 return sprintf(buf, "enabled\n");
 276         else if (state == 0)
 277                 return sprintf(buf, "disabled\n");
 278         else
 279                 return sprintf(buf, "unknown\n");
 280 }
 281
 282 static ssize_t regulator_state_show(struct device *dev,
 283                                    struct device_attribute *attr, char *buf)
 284 {
 285         struct regulator_dev *rdev = dev_get_drvdata(dev);
 286         ssize_t ret;
 287
 288         mutex_lock(&rdev->mutex);
 289         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 290         mutex_unlock(&rdev->mutex);
 291
 292         return ret;
 293 }
 294 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 295
 296 static ssize_t regulator_status_show(struct device *dev,
 297                                    struct device_attribute *attr, char *buf)
 298 {
 299         struct regulator_dev *rdev = dev_get_drvdata(dev);
 300         int status;
 301         char *label;
 302
 303         status = rdev->desc->ops->get_status(rdev);
 304         if (status < 0)
 305                 return status;
 306
 307         switch (status) {
 308         case REGULATOR_STATUS_OFF:
 309                 label = "off";
 310                 break;
 311         case REGULATOR_STATUS_ON:
 312                 label = "on";
 313                 break;
 314         case REGULATOR_STATUS_ERROR:
 315                 label = "error";
 316                 break;
 317         case REGULATOR_STATUS_FAST:
 318                 label = "fast";
 319                 break;
 320         case REGULATOR_STATUS_NORMAL:
 321                 label = "normal";
 322                 break;
 323         case REGULATOR_STATUS_IDLE:
 324                 label = "idle";
 325                 break;
 326         case REGULATOR_STATUS_STANDBY:
 327                 label = "standby";
 328                 break;
 329         default:
 330                 return -ERANGE;
 331         }
 332
 333         return sprintf(buf, "%s\n", label);
 334 }
 335 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 336
 337 static ssize_t regulator_min_uA_show(struct device *dev,
 338                                     struct device_attribute *attr, char *buf)
 339 {
 340         struct regulator_dev *rdev = dev_get_drvdata(dev);
 341
 342         if (!rdev->constraints)
 343                 return sprintf(buf, "constraint not defined\n");
 344
 345         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 346 }
 347 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 348
 349 static ssize_t regulator_max_uA_show(struct device *dev,
 350                                     struct device_attribute *attr, char *buf)
 351 {
 352         struct regulator_dev *rdev = dev_get_drvdata(dev);
 353
 354         if (!rdev->constraints)
 355                 return sprintf(buf, "constraint not defined\n");
 356
 357         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 358 }
 359 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 360
 361 static ssize_t regulator_min_uV_show(struct device *dev,
 362                                     struct device_attribute *attr, char *buf)
 363 {
 364         struct regulator_dev *rdev = dev_get_drvdata(dev);
 365
 366         if (!rdev->constraints)
 367                 return sprintf(buf, "constraint not defined\n");
 368
 369         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 370 }
 371 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 372
 373 static ssize_t regulator_max_uV_show(struct device *dev,
 374                                     struct device_attribute *attr, char *buf)
 375 {
 376         struct regulator_dev *rdev = dev_get_drvdata(dev);
 377
 378         if (!rdev->constraints)
 379                 return sprintf(buf, "constraint not defined\n");
 380
 381         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 382 }
 383 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 384
 385 static ssize_t regulator_total_uA_show(struct device *dev,
 386                                       struct device_attribute *attr, char *buf)
 387 {
 388         struct regulator_dev *rdev = dev_get_drvdata(dev);
 389         struct regulator *regulator;
 390         int uA = 0;
 391
 392         mutex_lock(&rdev->mutex);
 393         list_for_each_entry(regulator, &rdev->consumer_list, list)
 394                 uA += regulator->uA_load;
 395         mutex_unlock(&rdev->mutex);
 396         return sprintf(buf, "%d\n", uA);
 397 }
 398 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 399
 400 static ssize_t regulator_num_users_show(struct device *dev,
 401                                       struct device_attribute *attr, char *buf)
 402 {
 403         struct regulator_dev *rdev = dev_get_drvdata(dev);
 404         return sprintf(buf, "%d\n", rdev->use_count);
 405 }
 406
 407 static ssize_t regulator_type_show(struct device *dev,
 408                                   struct device_attribute *attr, char *buf)
 409 {
 410         struct regulator_dev *rdev = dev_get_drvdata(dev);
 411
 412         switch (rdev->desc->type) {
 413         case REGULATOR_VOLTAGE:
 414                 return sprintf(buf, "voltage\n");
 415         case REGULATOR_CURRENT:
 416                 return sprintf(buf, "current\n");
 417         }
 418         return sprintf(buf, "unknown\n");
 419 }
 420
 421 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 422                                 struct device_attribute *attr, char *buf)
 423 {
 424         struct regulator_dev *rdev = dev_get_drvdata(dev);
 425
 426         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 427 }
 428 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 429                 regulator_suspend_mem_uV_show, NULL);
 430
 431 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 432                                 struct device_attribute *attr, char *buf)
 433 {
 434         struct regulator_dev *rdev = dev_get_drvdata(dev);
 435
 436         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 437 }
 438 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 439                 regulator_suspend_disk_uV_show, NULL);
 440
 441 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 442                                 struct device_attribute *attr, char *buf)
 443 {
 444         struct regulator_dev *rdev = dev_get_drvdata(dev);
 445
 446         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 447 }
 448 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 449                 regulator_suspend_standby_uV_show, NULL);
 450
 451 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 452                                 struct device_attribute *attr, char *buf)
 453 {
 454         struct regulator_dev *rdev = dev_get_drvdata(dev);
 455
 456         return regulator_print_opmode(buf,
 457                 rdev->constraints->state_mem.mode);
 458 }
 459 static DEVICE_ATTR(suspend_mem_mode, 0444,
 460                 regulator_suspend_mem_mode_show, NULL);
 461
 462 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 463                                 struct device_attribute *attr, char *buf)
 464 {
 465         struct regulator_dev *rdev = dev_get_drvdata(dev);
 466
 467         return regulator_print_opmode(buf,
 468                 rdev->constraints->state_disk.mode);
 469 }
 470 static DEVICE_ATTR(suspend_disk_mode, 0444,
 471                 regulator_suspend_disk_mode_show, NULL);
 472
 473 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 474                                 struct device_attribute *attr, char *buf)
 475 {
 476         struct regulator_dev *rdev = dev_get_drvdata(dev);
 477
 478         return regulator_print_opmode(buf,
 479                 rdev->constraints->state_standby.mode);
 480 }
 481 static DEVICE_ATTR(suspend_standby_mode, 0444,
 482                 regulator_suspend_standby_mode_show, NULL);
 483
 484 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 485                                    struct device_attribute *attr, char *buf)
 486 {
 487         struct regulator_dev *rdev = dev_get_drvdata(dev);
 488
 489         return regulator_print_state(buf,
 490                         rdev->constraints->state_mem.enabled);
 491 }
 492 static DEVICE_ATTR(suspend_mem_state, 0444,
 493                 regulator_suspend_mem_state_show, NULL);
 494
 495 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 496                                    struct device_attribute *attr, char *buf)
 497 {
 498         struct regulator_dev *rdev = dev_get_drvdata(dev);
 499
 500         return regulator_print_state(buf,
 501                         rdev->constraints->state_disk.enabled);
 502 }
 503 static DEVICE_ATTR(suspend_disk_state, 0444,
 504                 regulator_suspend_disk_state_show, NULL);
 505
 506 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 507                                    struct device_attribute *attr, char *buf)
 508 {
 509         struct regulator_dev *rdev = dev_get_drvdata(dev);
 510
 511         return regulator_print_state(buf,
 512                         rdev->constraints->state_standby.enabled);
 513 }
 514 static DEVICE_ATTR(suspend_standby_state, 0444,
 515                 regulator_suspend_standby_state_show, NULL);
 516
 517
 518 /*
 519  * These are the only attributes are present for all regulators.
 520  * Other attributes are a function of regulator functionality.
 521  */
 522 static struct device_attribute regulator_dev_attrs[] = {
 523         __ATTR(name, 0444, regulator_name_show, NULL),
 524         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
 525         __ATTR(type, 0444, regulator_type_show, NULL),
 526         __ATTR_NULL,
 527 };
 528
 529 static void regulator_dev_release(struct device *dev)
 530 {
 531         struct regulator_dev *rdev = dev_get_drvdata(dev);
 532         kfree(rdev);
 533 }
 534
 535 static struct class regulator_class = {
 536         .name = "regulator",
 537         .dev_release = regulator_dev_release,
 538         .dev_attrs = regulator_dev_attrs,
 539 };
 540
 541 /* Calculate the new optimum regulator operating mode based on the new total
 542  * consumer load. All locks held by caller */
 543 static void drms_uA_update(struct regulator_dev *rdev)
 544 {
 545         struct regulator *sibling;
 546         int current_uA = 0, output_uV, input_uV, err;
 547         unsigned int mode;
 548
 549         err = regulator_check_drms(rdev);
 550         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 551             !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
 552                 return;
 553
 554         /* get output voltage */
 555         output_uV = rdev->desc->ops->get_voltage(rdev);
 556         if (output_uV <= 0)
 557                 return;
 558
 559         /* get input voltage */
 560         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
 561                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
 562         else
 563                 input_uV = rdev->constraints->input_uV;
 564         if (input_uV <= 0)
 565                 return;
 566
 567         /* calc total requested load */
 568         list_for_each_entry(sibling, &rdev->consumer_list, list)
 569                 current_uA += sibling->uA_load;
 570
 571         /* now get the optimum mode for our new total regulator load */
 572         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 573                                                   output_uV, current_uA);
 574
 575         /* check the new mode is allowed */
 576         err = regulator_check_mode(rdev, mode);
 577         if (err == 0)
 578                 rdev->desc->ops->set_mode(rdev, mode);
 579 }
 580
 581 static int suspend_set_state(struct regulator_dev *rdev,
 582         struct regulator_state *rstate)
 583 {
 584         int ret = 0;
 585         bool can_set_state;
 586
 587         can_set_state = rdev->desc->ops->set_suspend_enable &&
 588                 rdev->desc->ops->set_suspend_disable;
 589
 590         /* If we have no suspend mode configration don't set anything;
 591          * only warn if the driver actually makes the suspend mode
 592          * configurable.
 593          */
 594         if (!rstate->enabled && !rstate->disabled) {
 595                 if (can_set_state)
 596                         printk(KERN_WARNING "%s: No configuration for %s\n",
 597                                __func__, rdev_get_name(rdev));
 598                 return 0;
 599         }
 600
 601         if (rstate->enabled && rstate->disabled) {
 602                 printk(KERN_ERR "%s: invalid configuration for %s\n",
 603                        __func__, rdev_get_name(rdev));
 604                 return -EINVAL;
 605         }
 606
 607         if (!can_set_state) {
 608                 printk(KERN_ERR "%s: no way to set suspend state\n",
 609                         __func__);
 610                 return -EINVAL;
 611         }
 612
 613         if (rstate->enabled)
 614                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 615         else
 616                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 617         if (ret < 0) {
 618                 printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
 619                 return ret;
 620         }
 621
 622         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 623                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 624                 if (ret < 0) {
 625                         printk(KERN_ERR "%s: failed to set voltage\n",
 626                                 __func__);
 627                         return ret;
 628                 }
 629         }
 630
 631         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 632                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 633                 if (ret < 0) {
 634                         printk(KERN_ERR "%s: failed to set mode\n", __func__);
 635                         return ret;
 636                 }
 637         }
 638         return ret;
 639 }
 640
 641 /* locks held by caller */
 642 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 643 {
 644         if (!rdev->constraints)
 645                 return -EINVAL;
 646
 647         switch (state) {
 648         case PM_SUSPEND_STANDBY:
 649                 return suspend_set_state(rdev,
 650                         &rdev->constraints->state_standby);
 651         case PM_SUSPEND_MEM:
 652                 return suspend_set_state(rdev,
 653                         &rdev->constraints->state_mem);
 654         case PM_SUSPEND_MAX:
 655                 return suspend_set_state(rdev,
 656                         &rdev->constraints->state_disk);
 657         default:
 658                 return -EINVAL;
 659         }
 660 }
 661
 662 static void print_constraints(struct regulator_dev *rdev)
 663 {
 664         struct regulation_constraints *constraints = rdev->constraints;
 665         char buf[80] = "";
 666         int count = 0;
 667         int ret;
 668
 669         if (constraints->min_uV && constraints->max_uV) {
 670                 if (constraints->min_uV == constraints->max_uV)
 671                         count += sprintf(buf + count, "%d mV ",
 672                                          constraints->min_uV / 1000);
 673                 else
 674                         count += sprintf(buf + count, "%d <--> %d mV ",
 675                                          constraints->min_uV / 1000,
 676                                          constraints->max_uV / 1000);
 677         }
 678
 679         if (!constraints->min_uV ||
 680             constraints->min_uV != constraints->max_uV) {
 681                 ret = _regulator_get_voltage(rdev);
 682                 if (ret > 0)
 683                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 684         }
 685
 686         if (constraints->min_uA && constraints->max_uA) {
 687                 if (constraints->min_uA == constraints->max_uA)
 688                         count += sprintf(buf + count, "%d mA ",
 689                                          constraints->min_uA / 1000);
 690                 else
 691                         count += sprintf(buf + count, "%d <--> %d mA ",
 692                                          constraints->min_uA / 1000,
 693                                          constraints->max_uA / 1000);
 694         }
 695
 696         if (!constraints->min_uA ||
 697             constraints->min_uA != constraints->max_uA) {
 698                 ret = _regulator_get_current_limit(rdev);
 699                 if (ret > 0)
 700                         count += sprintf(buf + count, "at %d uA ", ret / 1000);
 701         }
 702
 703         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 704                 count += sprintf(buf + count, "fast ");
 705         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 706                 count += sprintf(buf + count, "normal ");
 707         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 708                 count += sprintf(buf + count, "idle ");
 709         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 710                 count += sprintf(buf + count, "standby");
 711
 712         printk(KERN_INFO "regulator: %s: %s\n", rdev_get_name(rdev), buf);
 713 }
 714
 715 static int machine_constraints_voltage(struct regulator_dev *rdev,
 716         struct regulation_constraints *constraints)
 717 {
 718         struct regulator_ops *ops = rdev->desc->ops;
 719         const char *name = rdev_get_name(rdev);
 720         int ret;
 721
 722         /* do we need to apply the constraint voltage */
 723         if (rdev->constraints->apply_uV &&
 724                 rdev->constraints->min_uV == rdev->constraints->max_uV &&
 725                 ops->set_voltage) {
 726                 ret = ops->set_voltage(rdev,
 727                         rdev->constraints->min_uV, rdev->constraints->max_uV);
 728                         if (ret < 0) {
 729                                 printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
 730                                        __func__,
 731                                        rdev->constraints->min_uV, name);
 732                                 rdev->constraints = NULL;
 733                                 return ret;
 734                         }
 735         }
 736
 737         /* constrain machine-level voltage specs to fit
 738          * the actual range supported by this regulator.
 739          */
 740         if (ops->list_voltage && rdev->desc->n_voltages) {
 741                 int     count = rdev->desc->n_voltages;
 742                 int     i;
 743                 int     min_uV = INT_MAX;
 744                 int     max_uV = INT_MIN;
 745                 int     cmin = constraints->min_uV;
 746                 int     cmax = constraints->max_uV;
 747
 748                 /* it's safe to autoconfigure fixed-voltage supplies
 749                    and the constraints are used by list_voltage. */
 750                 if (count == 1 && !cmin) {
 751                         cmin = 1;
 752                         cmax = INT_MAX;
 753                         constraints->min_uV = cmin;
 754                         constraints->max_uV = cmax;
 755                 }
 756
 757                 /* voltage constraints are optional */
 758                 if ((cmin == 0) && (cmax == 0))
 759                         return 0;
 760
 761                 /* else require explicit machine-level constraints */
 762                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 763                         pr_err("%s: %s '%s' voltage constraints\n",
 764                                        __func__, "invalid", name);
 765                         return -EINVAL;
 766                 }
 767
 768                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 769                 for (i = 0; i < count; i++) {
 770                         int     value;
 771
 772                         value = ops->list_voltage(rdev, i);
 773                         if (value <= 0)
 774                                 continue;
 775
 776                         /* maybe adjust [min_uV..max_uV] */
 777                         if (value >= cmin && value < min_uV)
 778                                 min_uV = value;
 779                         if (value <= cmax && value > max_uV)
 780                                 max_uV = value;
 781                 }
 782
 783                 /* final: [min_uV..max_uV] valid iff constraints valid */
 784                 if (max_uV < min_uV) {
 785                         pr_err("%s: %s '%s' voltage constraints\n",
 786                                        __func__, "unsupportable", name);
 787                         return -EINVAL;
 788                 }
 789
 790                 /* use regulator's subset of machine constraints */
 791                 if (constraints->min_uV < min_uV) {
 792                         pr_debug("%s: override '%s' %s, %d -> %d\n",
 793                                        __func__, name, "min_uV",
 794                                         constraints->min_uV, min_uV);
 795                         constraints->min_uV = min_uV;
 796                 }
 797                 if (constraints->max_uV > max_uV) {
 798                         pr_debug("%s: override '%s' %s, %d -> %d\n",
 799                                        __func__, name, "max_uV",
 800                                         constraints->max_uV, max_uV);
 801                         constraints->max_uV = max_uV;
 802                 }
 803         }
 804
 805         return 0;
 806 }
 807
 808 /**
 809  * set_machine_constraints - sets regulator constraints
 810  * @rdev: regulator source
 811  * @constraints: constraints to apply
 812  *
 813  * Allows platform initialisation code to define and constrain
 814  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 815  * Constraints *must* be set by platform code in order for some
 816  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 817  * set_mode.
 818  */
 819 static int set_machine_constraints(struct regulator_dev *rdev,
 820         struct regulation_constraints *constraints)
 821 {
 822         int ret = 0;
 823         const char *name;
 824         struct regulator_ops *ops = rdev->desc->ops;
 825
 826         rdev->constraints = constraints;
 827
 828         name = rdev_get_name(rdev);
 829
 830         ret = machine_constraints_voltage(rdev, constraints);
 831         if (ret != 0)
 832                 goto out;
 833
 834         /* do we need to setup our suspend state */
 835         if (constraints->initial_state) {
 836                 ret = suspend_prepare(rdev, constraints->initial_state);
 837                 if (ret < 0) {
 838                         printk(KERN_ERR "%s: failed to set suspend state for %s\n",
 839                                __func__, name);
 840                         rdev->constraints = NULL;
 841                         goto out;
 842                 }
 843         }
 844
 845         if (constraints->initial_mode) {
 846                 if (!ops->set_mode) {
 847                         printk(KERN_ERR "%s: no set_mode operation for %s\n",
 848                                __func__, name);
 849                         ret = -EINVAL;
 850                         goto out;
 851                 }
 852
 853                 ret = ops->set_mode(rdev, constraints->initial_mode);
 854                 if (ret < 0) {
 855                         printk(KERN_ERR
 856                                "%s: failed to set initial mode for %s: %d\n",
 857                                __func__, name, ret);
 858                         goto out;
 859                 }
 860         }
 861
 862         /* If the constraints say the regulator should be on at this point
 863          * and we have control then make sure it is enabled.
 864          */
 865         if ((constraints->always_on || constraints->boot_on) && ops->enable) {
 866                 ret = ops->enable(rdev);
 867                 if (ret < 0) {
 868                         printk(KERN_ERR "%s: failed to enable %s\n",
 869                                __func__, name);
 870                         rdev->constraints = NULL;
 871                         goto out;
 872                 }
 873         }
 874
 875         print_constraints(rdev);
 876 out:
 877         return ret;
 878 }
 879
 880 /**
 881  * set_supply - set regulator supply regulator
 882  * @rdev: regulator name
 883  * @supply_rdev: supply regulator name
 884  *
 885  * Called by platform initialisation code to set the supply regulator for this
 886  * regulator. This ensures that a regulators supply will also be enabled by the
 887  * core if it's child is enabled.
 888  */
 889 static int set_supply(struct regulator_dev *rdev,
 890         struct regulator_dev *supply_rdev)
 891 {
 892         int err;
 893
 894         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
 895                                 "supply");
 896         if (err) {
 897                 printk(KERN_ERR
 898                        "%s: could not add device link %s err %d\n",
 899                        __func__, supply_rdev->dev.kobj.name, err);
 900                        goto out;
 901         }
 902         rdev->supply = supply_rdev;
 903         list_add(&rdev->slist, &supply_rdev->supply_list);
 904 out:
 905         return err;
 906 }
 907
 908 /**
 909  * set_consumer_device_supply: Bind a regulator to a symbolic supply
 910  * @rdev:         regulator source
 911  * @consumer_dev: device the supply applies to
 912  * @consumer_dev_name: dev_name() string for device supply applies to
 913  * @supply:       symbolic name for supply
 914  *
 915  * Allows platform initialisation code to map physical regulator
 916  * sources to symbolic names for supplies for use by devices.  Devices
 917  * should use these symbolic names to request regulators, avoiding the
 918  * need to provide board-specific regulator names as platform data.
 919  *
 920  * Only one of consumer_dev and consumer_dev_name may be specified.
 921  */
 922 static int set_consumer_device_supply(struct regulator_dev *rdev,
 923         struct device *consumer_dev, const char *consumer_dev_name,
 924         const char *supply)
 925 {
 926         struct regulator_map *node;
 927         int has_dev;
 928
 929         if (consumer_dev && consumer_dev_name)
 930                 return -EINVAL;
 931
 932         if (!consumer_dev_name && consumer_dev)
 933                 consumer_dev_name = dev_name(consumer_dev);
 934
 935         if (supply == NULL)
 936                 return -EINVAL;
 937
 938         if (consumer_dev_name != NULL)
 939                 has_dev = 1;
 940         else
 941                 has_dev = 0;
 942
 943         list_for_each_entry(node, &regulator_map_list, list) {
 944                 if (consumer_dev_name != node->dev_name)
 945                         continue;
 946                 if (strcmp(node->supply, supply) != 0)
 947                         continue;
 948
 949                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
 950                                 dev_name(&node->regulator->dev),
 951                                 node->regulator->desc->name,
 952                                 supply,
 953                                 dev_name(&rdev->dev), rdev_get_name(rdev));
 954                 return -EBUSY;
 955         }
 956
 957         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
 958         if (node == NULL)
 959                 return -ENOMEM;
 960
 961         node->regulator = rdev;
 962         node->supply = supply;
 963
 964         if (has_dev) {
 965                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
 966                 if (node->dev_name == NULL) {
 967                         kfree(node);
 968                         return -ENOMEM;
 969                 }
 970         }
 971
 972         list_add(&node->list, &regulator_map_list);
 973         return 0;
 974 }
 975
 976 static void unset_consumer_device_supply(struct regulator_dev *rdev,
 977         const char *consumer_dev_name, struct device *consumer_dev)
 978 {
 979         struct regulator_map *node, *n;
 980
 981         if (consumer_dev && !consumer_dev_name)
 982                 consumer_dev_name = dev_name(consumer_dev);
 983
 984         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
 985                 if (rdev != node->regulator)
 986                         continue;
 987
 988                 if (consumer_dev_name && node->dev_name &&
 989                     strcmp(consumer_dev_name, node->dev_name))
 990                         continue;
 991
 992                 list_del(&node->list);
 993                 kfree(node->dev_name);
 994                 kfree(node);
 995                 return;
 996         }
 997 }
 998
 999 static void unset_regulator_supplies(struct regulator_dev *rdev)
1000 {
1001         struct regulator_map *node, *n;
1002
1003         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1004                 if (rdev == node->regulator) {
1005                         list_del(&node->list);
1006                         kfree(node->dev_name);
1007                         kfree(node);
1008                         return;
1009                 }
1010         }
1011 }
1012
1013 #define REG_STR_SIZE    32
1014
1015 static struct regulator *create_regulator(struct regulator_dev *rdev,
1016                                           struct device *dev,
1017                                           const char *supply_name)
1018 {
1019         struct regulator *regulator;
1020         char buf[REG_STR_SIZE];
1021         int err, size;
1022
1023         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1024         if (regulator == NULL)
1025                 return NULL;
1026
1027         mutex_lock(&rdev->mutex);
1028         regulator->rdev = rdev;
1029         list_add(&regulator->list, &rdev->consumer_list);
1030
1031         if (dev) {
1032                 /* create a 'requested_microamps_name' sysfs entry */
1033                 size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
1034                         supply_name);
1035                 if (size >= REG_STR_SIZE)
1036                         goto overflow_err;
1037
1038                 regulator->dev = dev;
1039                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1040                 if (regulator->dev_attr.attr.name == NULL)
1041                         goto attr_name_err;
1042
1043                 regulator->dev_attr.attr.owner = THIS_MODULE;
1044                 regulator->dev_attr.attr.mode = 0444;
1045                 regulator->dev_attr.show = device_requested_uA_show;
1046                 err = device_create_file(dev, &regulator->dev_attr);
1047                 if (err < 0) {
1048                         printk(KERN_WARNING "%s: could not add regulator_dev"
1049                                 " load sysfs\n", __func__);
1050                         goto attr_name_err;
1051                 }
1052
1053                 /* also add a link to the device sysfs entry */
1054                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1055                                  dev->kobj.name, supply_name);
1056                 if (size >= REG_STR_SIZE)
1057                         goto attr_err;
1058
1059                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1060                 if (regulator->supply_name == NULL)
1061                         goto attr_err;
1062
1063                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1064                                         buf);
1065                 if (err) {
1066                         printk(KERN_WARNING
1067                                "%s: could not add device link %s err %d\n",
1068                                __func__, dev->kobj.name, err);
1069                         device_remove_file(dev, &regulator->dev_attr);
1070                         goto link_name_err;
1071                 }
1072         }
1073         mutex_unlock(&rdev->mutex);
1074         return regulator;
1075 link_name_err:
1076         kfree(regulator->supply_name);
1077 attr_err:
1078         device_remove_file(regulator->dev, &regulator->dev_attr);
1079 attr_name_err:
1080         kfree(regulator->dev_attr.attr.name);
1081 overflow_err:
1082         list_del(&regulator->list);
1083         kfree(regulator);
1084         mutex_unlock(&rdev->mutex);
1085         return NULL;
1086 }
1087
1088 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1089 {
1090         if (!rdev->desc->ops->enable_time)
1091                 return 0;
1092         return rdev->desc->ops->enable_time(rdev);
1093 }
1094
1095 /* Internal regulator request function */
1096 static struct regulator *_regulator_get(struct device *dev, const char *id,
1097                                         int exclusive)
1098 {
1099         struct regulator_dev *rdev;
1100         struct regulator_map *map;
1101         struct regulator *regulator = ERR_PTR(-ENODEV);
1102         const char *devname = NULL;
1103         int ret;
1104
1105         if (id == NULL) {
1106                 printk(KERN_ERR "regulator: get() with no identifier\n");
1107                 return regulator;
1108         }
1109
1110         if (dev)
1111                 devname = dev_name(dev);
1112
1113         mutex_lock(&regulator_list_mutex);
1114
1115         list_for_each_entry(map, &regulator_map_list, list) {
1116                 /* If the mapping has a device set up it must match */
1117                 if (map->dev_name &&
1118                     (!devname || strcmp(map->dev_name, devname)))
1119                         continue;
1120
1121                 if (strcmp(map->supply, id) == 0) {
1122                         rdev = map->regulator;
1123                         goto found;
1124                 }
1125         }
1126         mutex_unlock(&regulator_list_mutex);
1127         return regulator;
1128
1129 found:
1130         if (rdev->exclusive) {
1131                 regulator = ERR_PTR(-EPERM);
1132                 goto out;
1133         }
1134
1135         if (exclusive && rdev->open_count) {
1136                 regulator = ERR_PTR(-EBUSY);
1137                 goto out;
1138         }
1139
1140         if (!try_module_get(rdev->owner))
1141                 goto out;
1142
1143         regulator = create_regulator(rdev, dev, id);
1144         if (regulator == NULL) {
1145                 regulator = ERR_PTR(-ENOMEM);
1146                 module_put(rdev->owner);
1147         }
1148
1149         rdev->open_count++;
1150         if (exclusive) {
1151                 rdev->exclusive = 1;
1152
1153                 ret = _regulator_is_enabled(rdev);
1154                 if (ret > 0)
1155                         rdev->use_count = 1;
1156                 else
1157                         rdev->use_count = 0;
1158         }
1159
1160 out:
1161         mutex_unlock(&regulator_list_mutex);
1162
1163         return regulator;
1164 }
1165
1166 /**
1167  * regulator_get - lookup and obtain a reference to a regulator.
1168  * @dev: device for regulator "consumer"
1169  * @id: Supply name or regulator ID.
1170  *
1171  * Returns a struct regulator corresponding to the regulator producer,
1172  * or IS_ERR() condition containing errno.
1173  *
1174  * Use of supply names configured via regulator_set_device_supply() is
1175  * strongly encouraged.  It is recommended that the supply name used
1176  * should match the name used for the supply and/or the relevant
1177  * device pins in the datasheet.
1178  */
1179 struct regulator *regulator_get(struct device *dev, const char *id)
1180 {
1181         return _regulator_get(dev, id, 0);
1182 }
1183 EXPORT_SYMBOL_GPL(regulator_get);
1184
1185 /**
1186  * regulator_get_exclusive - obtain exclusive access to a regulator.
1187  * @dev: device for regulator "consumer"
1188  * @id: Supply name or regulator ID.
1189  *
1190  * Returns a struct regulator corresponding to the regulator producer,
1191  * or IS_ERR() condition containing errno.  Other consumers will be
1192  * unable to obtain this reference is held and the use count for the
1193  * regulator will be initialised to reflect the current state of the
1194  * regulator.
1195  *
1196  * This is intended for use by consumers which cannot tolerate shared
1197  * use of the regulator such as those which need to force the
1198  * regulator off for correct operation of the hardware they are
1199  * controlling.
1200  *
1201  * Use of supply names configured via regulator_set_device_supply() is
1202  * strongly encouraged.  It is recommended that the supply name used
1203  * should match the name used for the supply and/or the relevant
1204  * device pins in the datasheet.
1205  */
1206 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1207 {
1208         return _regulator_get(dev, id, 1);
1209 }
1210 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1211
1212 /**
1213  * regulator_put - "free" the regulator source
1214  * @regulator: regulator source
1215  *
1216  * Note: drivers must ensure that all regulator_enable calls made on this
1217  * regulator source are balanced by regulator_disable calls prior to calling
1218  * this function.
1219  */
1220 void regulator_put(struct regulator *regulator)
1221 {
1222         struct regulator_dev *rdev;
1223
1224         if (regulator == NULL || IS_ERR(regulator))
1225                 return;
1226
1227         mutex_lock(&regulator_list_mutex);
1228         rdev = regulator->rdev;
1229
1230         /* remove any sysfs entries */
1231         if (regulator->dev) {
1232                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1233                 kfree(regulator->supply_name);
1234                 device_remove_file(regulator->dev, &regulator->dev_attr);
1235                 kfree(regulator->dev_attr.attr.name);
1236         }
1237         list_del(&regulator->list);
1238         kfree(regulator);
1239
1240         rdev->open_count--;
1241         rdev->exclusive = 0;
1242
1243         module_put(rdev->owner);
1244         mutex_unlock(&regulator_list_mutex);
1245 }
1246 EXPORT_SYMBOL_GPL(regulator_put);
1247
1248 static int _regulator_can_change_status(struct regulator_dev *rdev)
1249 {
1250         if (!rdev->constraints)
1251                 return 0;
1252
1253         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1254                 return 1;
1255         else
1256                 return 0;
1257 }
1258
1259 /* locks held by regulator_enable() */
1260 static int _regulator_enable(struct regulator_dev *rdev)
1261 {
1262         int ret, delay;
1263
1264         /* do we need to enable the supply regulator first */
1265         if (rdev->supply) {
1266                 ret = _regulator_enable(rdev->supply);
1267                 if (ret < 0) {
1268                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1269                                __func__, rdev_get_name(rdev), ret);
1270                         return ret;
1271                 }
1272         }
1273
1274         /* check voltage and requested load before enabling */
1275         if (rdev->constraints &&
1276             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1277                 drms_uA_update(rdev);
1278
1279         if (rdev->use_count == 0) {
1280                 /* The regulator may on if it's not switchable or left on */
1281                 ret = _regulator_is_enabled(rdev);
1282                 if (ret == -EINVAL || ret == 0) {
1283                         if (!_regulator_can_change_status(rdev))
1284                                 return -EPERM;
1285
1286                         if (!rdev->desc->ops->enable)
1287                                 return -EINVAL;
1288
1289                         /* Query before enabling in case configuration
1290                          * dependant.  */
1291                         ret = _regulator_get_enable_time(rdev);
1292                         if (ret >= 0) {
1293                                 delay = ret;
1294                         } else {
1295                                 printk(KERN_WARNING
1296                                         "%s: enable_time() failed for %s: %d\n",
1297                                         __func__, rdev_get_name(rdev),
1298                                         ret);
1299                                 delay = 0;
1300                         }
1301
1302                         /* Allow the regulator to ramp; it would be useful
1303                          * to extend this for bulk operations so that the
1304                          * regulators can ramp together.  */
1305                         ret = rdev->desc->ops->enable(rdev);
1306                         if (ret < 0)
1307                                 return ret;
1308
1309                         if (delay >= 1000)
1310                                 mdelay(delay / 1000);
1311                         else if (delay)
1312                                 udelay(delay);
1313
1314                 } else if (ret < 0) {
1315                         printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
1316                                __func__, rdev_get_name(rdev), ret);
1317                         return ret;
1318                 }
1319                 /* Fallthrough on positive return values - already enabled */
1320         }
1321
1322         rdev->use_count++;
1323
1324         return 0;
1325 }
1326
1327 /**
1328  * regulator_enable - enable regulator output
1329  * @regulator: regulator source
1330  *
1331  * Request that the regulator be enabled with the regulator output at
1332  * the predefined voltage or current value.  Calls to regulator_enable()
1333  * must be balanced with calls to regulator_disable().
1334  *
1335  * NOTE: the output value can be set by other drivers, boot loader or may be
1336  * hardwired in the regulator.
1337  */
1338 int regulator_enable(struct regulator *regulator)
1339 {
1340         struct regulator_dev *rdev = regulator->rdev;
1341         int ret = 0;
1342
1343         mutex_lock(&rdev->mutex);
1344         ret = _regulator_enable(rdev);
1345         mutex_unlock(&rdev->mutex);
1346         return ret;
1347 }
1348 EXPORT_SYMBOL_GPL(regulator_enable);
1349
1350 /* locks held by regulator_disable() */
1351 static int _regulator_disable(struct regulator_dev *rdev)
1352 {
1353         int ret = 0;
1354
1355         if (WARN(rdev->use_count <= 0,
1356                         "unbalanced disables for %s\n",
1357                         rdev_get_name(rdev)))
1358                 return -EIO;
1359
1360         /* are we the last user and permitted to disable ? */
1361         if (rdev->use_count == 1 &&
1362             (rdev->constraints && !rdev->constraints->always_on)) {
1363
1364                 /* we are last user */
1365                 if (_regulator_can_change_status(rdev) &&
1366                     rdev->desc->ops->disable) {
1367                         ret = rdev->desc->ops->disable(rdev);
1368                         if (ret < 0) {
1369                                 printk(KERN_ERR "%s: failed to disable %s\n",
1370                                        __func__, rdev_get_name(rdev));
1371                                 return ret;
1372                         }
1373
1374                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1375                                              NULL);
1376                 }
1377
1378                 /* decrease our supplies ref count and disable if required */
1379                 if (rdev->supply)
1380                         _regulator_disable(rdev->supply);
1381
1382                 rdev->use_count = 0;
1383         } else if (rdev->use_count > 1) {
1384
1385                 if (rdev->constraints &&
1386                         (rdev->constraints->valid_ops_mask &
1387                         REGULATOR_CHANGE_DRMS))
1388                         drms_uA_update(rdev);
1389
1390                 rdev->use_count--;
1391         }
1392         return ret;
1393 }
1394
1395 /**
1396  * regulator_disable - disable regulator output
1397  * @regulator: regulator source
1398  *
1399  * Disable the regulator output voltage or current.  Calls to
1400  * regulator_enable() must be balanced with calls to
1401  * regulator_disable().
1402  *
1403  * NOTE: this will only disable the regulator output if no other consumer
1404  * devices have it enabled, the regulator device supports disabling and
1405  * machine constraints permit this operation.
1406  */
1407 int regulator_disable(struct regulator *regulator)
1408 {
1409         struct regulator_dev *rdev = regulator->rdev;
1410         int ret = 0;
1411
1412         mutex_lock(&rdev->mutex);
1413         ret = _regulator_disable(rdev);
1414         mutex_unlock(&rdev->mutex);
1415         return ret;
1416 }
1417 EXPORT_SYMBOL_GPL(regulator_disable);
1418
1419 /* locks held by regulator_force_disable() */
1420 static int _regulator_force_disable(struct regulator_dev *rdev)
1421 {
1422         int ret = 0;
1423
1424         /* force disable */
1425         if (rdev->desc->ops->disable) {
1426                 /* ah well, who wants to live forever... */
1427                 ret = rdev->desc->ops->disable(rdev);
1428                 if (ret < 0) {
1429                         printk(KERN_ERR "%s: failed to force disable %s\n",
1430                                __func__, rdev_get_name(rdev));
1431                         return ret;
1432                 }
1433                 /* notify other consumers that power has been forced off */
1434                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1435                         REGULATOR_EVENT_DISABLE, NULL);
1436         }
1437
1438         /* decrease our supplies ref count and disable if required */
1439         if (rdev->supply)
1440                 _regulator_disable(rdev->supply);
1441
1442         rdev->use_count = 0;
1443         return ret;
1444 }
1445
1446 /**
1447  * regulator_force_disable - force disable regulator output
1448  * @regulator: regulator source
1449  *
1450  * Forcibly disable the regulator output voltage or current.
1451  * NOTE: this *will* disable the regulator output even if other consumer
1452  * devices have it enabled. This should be used for situations when device
1453  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1454  */
1455 int regulator_force_disable(struct regulator *regulator)
1456 {
1457         int ret;
1458
1459         mutex_lock(&regulator->rdev->mutex);
1460         regulator->uA_load = 0;
1461         ret = _regulator_force_disable(regulator->rdev);
1462         mutex_unlock(&regulator->rdev->mutex);
1463         return ret;
1464 }
1465 EXPORT_SYMBOL_GPL(regulator_force_disable);
1466
1467 static int _regulator_is_enabled(struct regulator_dev *rdev)
1468 {
1469         /* If we don't know then assume that the regulator is always on */
1470         if (!rdev->desc->ops->is_enabled)
1471                 return 1;
1472
1473         return rdev->desc->ops->is_enabled(rdev);
1474 }
1475
1476 /**
1477  * regulator_is_enabled - is the regulator output enabled
1478  * @regulator: regulator source
1479  *
1480  * Returns positive if the regulator driver backing the source/client
1481  * has requested that the device be enabled, zero if it hasn't, else a
1482  * negative errno code.
1483  *
1484  * Note that the device backing this regulator handle can have multiple
1485  * users, so it might be enabled even if regulator_enable() was never
1486  * called for this particular source.
1487  */
1488 int regulator_is_enabled(struct regulator *regulator)
1489 {
1490         int ret;
1491
1492         mutex_lock(&regulator->rdev->mutex);
1493         ret = _regulator_is_enabled(regulator->rdev);
1494         mutex_unlock(&regulator->rdev->mutex);
1495
1496         return ret;
1497 }
1498 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1499
1500 /**
1501  * regulator_count_voltages - count regulator_list_voltage() selectors
1502  * @regulator: regulator source
1503  *
1504  * Returns number of selectors, or negative errno.  Selectors are
1505  * numbered starting at zero, and typically correspond to bitfields
1506  * in hardware registers.
1507  */
1508 int regulator_count_voltages(struct regulator *regulator)
1509 {
1510         struct regulator_dev    *rdev = regulator->rdev;
1511
1512         return rdev->desc->n_voltages ? : -EINVAL;
1513 }
1514 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1515
1516 /**
1517  * regulator_list_voltage - enumerate supported voltages
1518  * @regulator: regulator source
1519  * @selector: identify voltage to list
1520  * Context: can sleep
1521  *
1522  * Returns a voltage that can be passed to @regulator_set_voltage(),
1523  * zero if this selector code can't be used on this sytem, or a
1524  * negative errno.
1525  */
1526 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1527 {
1528         struct regulator_dev    *rdev = regulator->rdev;
1529         struct regulator_ops    *ops = rdev->desc->ops;
1530         int                     ret;
1531
1532         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1533                 return -EINVAL;
1534
1535         mutex_lock(&rdev->mutex);
1536         ret = ops->list_voltage(rdev, selector);
1537         mutex_unlock(&rdev->mutex);
1538
1539         if (ret > 0) {
1540                 if (ret < rdev->constraints->min_uV)
1541                         ret = 0;
1542                 else if (ret > rdev->constraints->max_uV)
1543                         ret = 0;
1544         }
1545
1546         return ret;
1547 }
1548 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1549
1550 /**
1551  * regulator_is_supported_voltage - check if a voltage range can be supported
1552  *
1553  * @regulator: Regulator to check.
1554  * @min_uV: Minimum required voltage in uV.
1555  * @max_uV: Maximum required voltage in uV.
1556  *
1557  * Returns a boolean or a negative error code.
1558  */
1559 int regulator_is_supported_voltage(struct regulator *regulator,
1560                                    int min_uV, int max_uV)
1561 {
1562         int i, voltages, ret;
1563
1564         ret = regulator_count_voltages(regulator);
1565         if (ret < 0)
1566                 return ret;
1567         voltages = ret;
1568
1569         for (i = 0; i < voltages; i++) {
1570                 ret = regulator_list_voltage(regulator, i);
1571
1572                 if (ret >= min_uV && ret <= max_uV)
1573                         return 1;
1574         }
1575
1576         return 0;
1577 }
1578
1579 /**
1580  * regulator_set_voltage - set regulator output voltage
1581  * @regulator: regulator source
1582  * @min_uV: Minimum required voltage in uV
1583  * @max_uV: Maximum acceptable voltage in uV
1584  *
1585  * Sets a voltage regulator to the desired output voltage. This can be set
1586  * during any regulator state. IOW, regulator can be disabled or enabled.
1587  *
1588  * If the regulator is enabled then the voltage will change to the new value
1589  * immediately otherwise if the regulator is disabled the regulator will
1590  * output at the new voltage when enabled.
1591  *
1592  * NOTE: If the regulator is shared between several devices then the lowest
1593  * request voltage that meets the system constraints will be used.
1594  * Regulator system constraints must be set for this regulator before
1595  * calling this function otherwise this call will fail.
1596  */
1597 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1598 {
1599         struct regulator_dev *rdev = regulator->rdev;
1600         int ret;
1601
1602         mutex_lock(&rdev->mutex);
1603
1604         /* sanity check */
1605         if (!rdev->desc->ops->set_voltage) {
1606                 ret = -EINVAL;
1607                 goto out;
1608         }
1609
1610         /* constraints check */
1611         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1612         if (ret < 0)
1613                 goto out;
1614         regulator->min_uV = min_uV;
1615         regulator->max_uV = max_uV;
1616         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1617
1618 out:
1619         _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1620         mutex_unlock(&rdev->mutex);
1621         return ret;
1622 }
1623 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1624
1625 static int _regulator_get_voltage(struct regulator_dev *rdev)
1626 {
1627         /* sanity check */
1628         if (rdev->desc->ops->get_voltage)
1629                 return rdev->desc->ops->get_voltage(rdev);
1630         else
1631                 return -EINVAL;
1632 }
1633
1634 /**
1635  * regulator_get_voltage - get regulator output voltage
1636  * @regulator: regulator source
1637  *
1638  * This returns the current regulator voltage in uV.
1639  *
1640  * NOTE: If the regulator is disabled it will return the voltage value. This
1641  * function should not be used to determine regulator state.
1642  */
1643 int regulator_get_voltage(struct regulator *regulator)
1644 {
1645         int ret;
1646
1647         mutex_lock(&regulator->rdev->mutex);
1648
1649         ret = _regulator_get_voltage(regulator->rdev);
1650
1651         mutex_unlock(&regulator->rdev->mutex);
1652
1653         return ret;
1654 }
1655 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1656
1657 /**
1658  * regulator_set_current_limit - set regulator output current limit
1659  * @regulator: regulator source
1660  * @min_uA: Minimuum supported current in uA
1661  * @max_uA: Maximum supported current in uA
1662  *
1663  * Sets current sink to the desired output current. This can be set during
1664  * any regulator state. IOW, regulator can be disabled or enabled.
1665  *
1666  * If the regulator is enabled then the current will change to the new value
1667  * immediately otherwise if the regulator is disabled the regulator will
1668  * output at the new current when enabled.
1669  *
1670  * NOTE: Regulator system constraints must be set for this regulator before
1671  * calling this function otherwise this call will fail.
1672  */
1673 int regulator_set_current_limit(struct regulator *regulator,
1674                                int min_uA, int max_uA)
1675 {
1676         struct regulator_dev *rdev = regulator->rdev;
1677         int ret;
1678
1679         mutex_lock(&rdev->mutex);
1680
1681         /* sanity check */
1682         if (!rdev->desc->ops->set_current_limit) {
1683                 ret = -EINVAL;
1684                 goto out;
1685         }
1686
1687         /* constraints check */
1688         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1689         if (ret < 0)
1690                 goto out;
1691
1692         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1693 out:
1694         mutex_unlock(&rdev->mutex);
1695         return ret;
1696 }
1697 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1698
1699 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1700 {
1701         int ret;
1702
1703         mutex_lock(&rdev->mutex);
1704
1705         /* sanity check */
1706         if (!rdev->desc->ops->get_current_limit) {
1707                 ret = -EINVAL;
1708                 goto out;
1709         }
1710
1711         ret = rdev->desc->ops->get_current_limit(rdev);
1712 out:
1713         mutex_unlock(&rdev->mutex);
1714         return ret;
1715 }
1716
1717 /**
1718  * regulator_get_current_limit - get regulator output current
1719  * @regulator: regulator source
1720  *
1721  * This returns the current supplied by the specified current sink in uA.
1722  *
1723  * NOTE: If the regulator is disabled it will return the current value. This
1724  * function should not be used to determine regulator state.
1725  */
1726 int regulator_get_current_limit(struct regulator *regulator)
1727 {
1728         return _regulator_get_current_limit(regulator->rdev);
1729 }
1730 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1731
1732 /**
1733  * regulator_set_mode - set regulator operating mode
1734  * @regulator: regulator source
1735  * @mode: operating mode - one of the REGULATOR_MODE constants
1736  *
1737  * Set regulator operating mode to increase regulator efficiency or improve
1738  * regulation performance.
1739  *
1740  * NOTE: Regulator system constraints must be set for this regulator before
1741  * calling this function otherwise this call will fail.
1742  */
1743 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1744 {
1745         struct regulator_dev *rdev = regulator->rdev;
1746         int ret;
1747
1748         mutex_lock(&rdev->mutex);
1749
1750         /* sanity check */
1751         if (!rdev->desc->ops->set_mode) {
1752                 ret = -EINVAL;
1753                 goto out;
1754         }
1755
1756         /* constraints check */
1757         ret = regulator_check_mode(rdev, mode);
1758         if (ret < 0)
1759                 goto out;
1760
1761         ret = rdev->desc->ops->set_mode(rdev, mode);
1762 out:
1763         mutex_unlock(&rdev->mutex);
1764         return ret;
1765 }
1766 EXPORT_SYMBOL_GPL(regulator_set_mode);
1767
1768 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1769 {
1770         int ret;
1771
1772         mutex_lock(&rdev->mutex);
1773
1774         /* sanity check */
1775         if (!rdev->desc->ops->get_mode) {
1776                 ret = -EINVAL;
1777                 goto out;
1778         }
1779
1780         ret = rdev->desc->ops->get_mode(rdev);
1781 out:
1782         mutex_unlock(&rdev->mutex);
1783         return ret;
1784 }
1785
1786 /**
1787  * regulator_get_mode - get regulator operating mode
1788  * @regulator: regulator source
1789  *
1790  * Get the current regulator operating mode.
1791  */
1792 unsigned int regulator_get_mode(struct regulator *regulator)
1793 {
1794         return _regulator_get_mode(regulator->rdev);
1795 }
1796 EXPORT_SYMBOL_GPL(regulator_get_mode);
1797
1798 /**
1799  * regulator_set_optimum_mode - set regulator optimum operating mode
1800  * @regulator: regulator source
1801  * @uA_load: load current
1802  *
1803  * Notifies the regulator core of a new device load. This is then used by
1804  * DRMS (if enabled by constraints) to set the most efficient regulator
1805  * operating mode for the new regulator loading.
1806  *
1807  * Consumer devices notify their supply regulator of the maximum power
1808  * they will require (can be taken from device datasheet in the power
1809  * consumption tables) when they change operational status and hence power
1810  * state. Examples of operational state changes that can affect power
1811  * consumption are :-
1812  *
1813  *    o Device is opened / closed.
1814  *    o Device I/O is about to begin or has just finished.
1815  *    o Device is idling in between work.
1816  *
1817  * This information is also exported via sysfs to userspace.
1818  *
1819  * DRMS will sum the total requested load on the regulator and change
1820  * to the most efficient operating mode if platform constraints allow.
1821  *
1822  * Returns the new regulator mode or error.
1823  */
1824 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1825 {
1826         struct regulator_dev *rdev = regulator->rdev;
1827         struct regulator *consumer;
1828         int ret, output_uV, input_uV, total_uA_load = 0;
1829         unsigned int mode;
1830
1831         mutex_lock(&rdev->mutex);
1832
1833         regulator->uA_load = uA_load;
1834         ret = regulator_check_drms(rdev);
1835         if (ret < 0)
1836                 goto out;
1837         ret = -EINVAL;
1838
1839         /* sanity check */
1840         if (!rdev->desc->ops->get_optimum_mode)
1841                 goto out;
1842
1843         /* get output voltage */
1844         output_uV = rdev->desc->ops->get_voltage(rdev);
1845         if (output_uV <= 0) {
1846                 printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1847                         __func__, rdev_get_name(rdev));
1848                 goto out;
1849         }
1850
1851         /* get input voltage */
1852         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1853                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1854         else
1855                 input_uV = rdev->constraints->input_uV;
1856         if (input_uV <= 0) {
1857                 printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1858                         __func__, rdev_get_name(rdev));
1859                 goto out;
1860         }
1861
1862         /* calc total requested load for this regulator */
1863         list_for_each_entry(consumer, &rdev->consumer_list, list)
1864                 total_uA_load += consumer->uA_load;
1865
1866         mode = rdev->desc->ops->get_optimum_mode(rdev,
1867                                                  input_uV, output_uV,
1868                                                  total_uA_load);
1869         ret = regulator_check_mode(rdev, mode);
1870         if (ret < 0) {
1871                 printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1872                         " %d uA %d -> %d uV\n", __func__, rdev_get_name(rdev),
1873                         total_uA_load, input_uV, output_uV);
1874                 goto out;
1875         }
1876
1877         ret = rdev->desc->ops->set_mode(rdev, mode);
1878         if (ret < 0) {
1879                 printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1880                         __func__, mode, rdev_get_name(rdev));
1881                 goto out;
1882         }
1883         ret = mode;
1884 out:
1885         mutex_unlock(&rdev->mutex);
1886         return ret;
1887 }
1888 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1889
1890 /**
1891  * regulator_register_notifier - register regulator event notifier
1892  * @regulator: regulator source
1893  * @nb: notifier block
1894  *
1895  * Register notifier block to receive regulator events.
1896  */
1897 int regulator_register_notifier(struct regulator *regulator,
1898                               struct notifier_block *nb)
1899 {
1900         return blocking_notifier_chain_register(&regulator->rdev->notifier,
1901                                                 nb);
1902 }
1903 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1904
1905 /**
1906  * regulator_unregister_notifier - unregister regulator event notifier
1907  * @regulator: regulator source
1908  * @nb: notifier block
1909  *
1910  * Unregister regulator event notifier block.
1911  */
1912 int regulator_unregister_notifier(struct regulator *regulator,
1913                                 struct notifier_block *nb)
1914 {
1915         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1916                                                   nb);
1917 }
1918 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1919
1920 /* notify regulator consumers and downstream regulator consumers.
1921  * Note mutex must be held by caller.
1922  */
1923 static void _notifier_call_chain(struct regulator_dev *rdev,
1924                                   unsigned long event, void *data)
1925 {
1926         struct regulator_dev *_rdev;
1927
1928         /* call rdev chain first */
1929         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1930
1931         /* now notify regulator we supply */
1932         list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1933                 mutex_lock(&_rdev->mutex);
1934                 _notifier_call_chain(_rdev, event, data);
1935                 mutex_unlock(&_rdev->mutex);
1936         }
1937 }
1938
1939 /**
1940  * regulator_bulk_get - get multiple regulator consumers
1941  *
1942  * @dev:           Device to supply
1943  * @num_consumers: Number of consumers to register
1944  * @consumers:     Configuration of consumers; clients are stored here.
1945  *
1946  * @return 0 on success, an errno on failure.
1947  *
1948  * This helper function allows drivers to get several regulator
1949  * consumers in one operation.  If any of the regulators cannot be
1950  * acquired then any regulators that were allocated will be freed
1951  * before returning to the caller.
1952  */
1953 int regulator_bulk_get(struct device *dev, int num_consumers,
1954                        struct regulator_bulk_data *consumers)
1955 {
1956         int i;
1957         int ret;
1958
1959         for (i = 0; i < num_consumers; i++)
1960                 consumers[i].consumer = NULL;
1961
1962         for (i = 0; i < num_consumers; i++) {
1963                 consumers[i].consumer = regulator_get(dev,
1964                                                       consumers[i].supply);
1965                 if (IS_ERR(consumers[i].consumer)) {
1966                         ret = PTR_ERR(consumers[i].consumer);
1967                         dev_err(dev, "Failed to get supply '%s': %d\n",
1968                                 consumers[i].supply, ret);
1969                         consumers[i].consumer = NULL;
1970                         goto err;
1971                 }
1972         }
1973
1974         return 0;
1975
1976 err:
1977         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1978                 regulator_put(consumers[i].consumer);
1979
1980         return ret;
1981 }
1982 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1983
1984 /**
1985  * regulator_bulk_enable - enable multiple regulator consumers
1986  *
1987  * @num_consumers: Number of consumers
1988  * @consumers:     Consumer data; clients are stored here.
1989  * @return         0 on success, an errno on failure
1990  *
1991  * This convenience API allows consumers to enable multiple regulator
1992  * clients in a single API call.  If any consumers cannot be enabled
1993  * then any others that were enabled will be disabled again prior to
1994  * return.
1995  */
1996 int regulator_bulk_enable(int num_consumers,
1997                           struct regulator_bulk_data *consumers)
1998 {
1999         int i;
2000         int ret;
2001
2002         for (i = 0; i < num_consumers; i++) {
2003                 ret = regulator_enable(consumers[i].consumer);
2004                 if (ret != 0)
2005                         goto err;
2006         }
2007
2008         return 0;
2009
2010 err:
2011         printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
2012         for (--i; i >= 0; --i)
2013                 regulator_disable(consumers[i].consumer);
2014
2015         return ret;
2016 }
2017 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2018
2019 /**
2020  * regulator_bulk_disable - disable multiple regulator consumers
2021  *
2022  * @num_consumers: Number of consumers
2023  * @consumers:     Consumer data; clients are stored here.
2024  * @return         0 on success, an errno on failure
2025  *
2026  * This convenience API allows consumers to disable multiple regulator
2027  * clients in a single API call.  If any consumers cannot be enabled
2028  * then any others that were disabled will be disabled again prior to
2029  * return.
2030  */
2031 int regulator_bulk_disable(int num_consumers,
2032                            struct regulator_bulk_data *consumers)
2033 {
2034         int i;
2035         int ret;
2036
2037         for (i = 0; i < num_consumers; i++) {
2038                 ret = regulator_disable(consumers[i].consumer);
2039                 if (ret != 0)
2040                         goto err;
2041         }
2042
2043         return 0;
2044
2045 err:
2046         printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
2047                ret);
2048         for (--i; i >= 0; --i)
2049                 regulator_enable(consumers[i].consumer);
2050
2051         return ret;
2052 }
2053 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2054
2055 /**
2056  * regulator_bulk_free - free multiple regulator consumers
2057  *
2058  * @num_consumers: Number of consumers
2059  * @consumers:     Consumer data; clients are stored here.
2060  *
2061  * This convenience API allows consumers to free multiple regulator
2062  * clients in a single API call.
2063  */
2064 void regulator_bulk_free(int num_consumers,
2065                          struct regulator_bulk_data *consumers)
2066 {
2067         int i;
2068
2069         for (i = 0; i < num_consumers; i++) {
2070                 regulator_put(consumers[i].consumer);
2071                 consumers[i].consumer = NULL;
2072         }
2073 }
2074 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2075
2076 /**
2077  * regulator_notifier_call_chain - call regulator event notifier
2078  * @rdev: regulator source
2079  * @event: notifier block
2080  * @data: callback-specific data.
2081  *
2082  * Called by regulator drivers to notify clients a regulator event has
2083  * occurred. We also notify regulator clients downstream.
2084  * Note lock must be held by caller.
2085  */
2086 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2087                                   unsigned long event, void *data)
2088 {
2089         _notifier_call_chain(rdev, event, data);
2090         return NOTIFY_DONE;
2091
2092 }
2093 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2094
2095 /**
2096  * regulator_mode_to_status - convert a regulator mode into a status
2097  *
2098  * @mode: Mode to convert
2099  *
2100  * Convert a regulator mode into a status.
2101  */
2102 int regulator_mode_to_status(unsigned int mode)
2103 {
2104         switch (mode) {
2105         case REGULATOR_MODE_FAST:
2106                 return REGULATOR_STATUS_FAST;
2107         case REGULATOR_MODE_NORMAL:
2108                 return REGULATOR_STATUS_NORMAL;
2109         case REGULATOR_MODE_IDLE:
2110                 return REGULATOR_STATUS_IDLE;
2111         case REGULATOR_STATUS_STANDBY:
2112                 return REGULATOR_STATUS_STANDBY;
2113         default:
2114                 return 0;
2115         }
2116 }
2117 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2118
2119 /*
2120  * To avoid cluttering sysfs (and memory) with useless state, only
2121  * create attributes that can be meaningfully displayed.
2122  */
2123 static int add_regulator_attributes(struct regulator_dev *rdev)
2124 {
2125         struct device           *dev = &rdev->dev;
2126         struct regulator_ops    *ops = rdev->desc->ops;
2127         int                     status = 0;
2128
2129         /* some attributes need specific methods to be displayed */
2130         if (ops->get_voltage) {
2131                 status = device_create_file(dev, &dev_attr_microvolts);
2132                 if (status < 0)
2133                         return status;
2134         }
2135         if (ops->get_current_limit) {
2136                 status = device_create_file(dev, &dev_attr_microamps);
2137                 if (status < 0)
2138                         return status;
2139         }
2140         if (ops->get_mode) {
2141                 status = device_create_file(dev, &dev_attr_opmode);
2142                 if (status < 0)
2143                         return status;
2144         }
2145         if (ops->is_enabled) {
2146                 status = device_create_file(dev, &dev_attr_state);
2147                 if (status < 0)
2148                         return status;
2149         }
2150         if (ops->get_status) {
2151                 status = device_create_file(dev, &dev_attr_status);
2152                 if (status < 0)
2153                         return status;
2154         }
2155
2156         /* some attributes are type-specific */
2157         if (rdev->desc->type == REGULATOR_CURRENT) {
2158                 status = device_create_file(dev, &dev_attr_requested_microamps);
2159                 if (status < 0)
2160                         return status;
2161         }
2162
2163         /* all the other attributes exist to support constraints;
2164          * don't show them if there are no constraints, or if the
2165          * relevant supporting methods are missing.
2166          */
2167         if (!rdev->constraints)
2168                 return status;
2169
2170         /* constraints need specific supporting methods */
2171         if (ops->set_voltage) {
2172                 status = device_create_file(dev, &dev_attr_min_microvolts);
2173                 if (status < 0)
2174                         return status;
2175                 status = device_create_file(dev, &dev_attr_max_microvolts);
2176                 if (status < 0)
2177                         return status;
2178         }
2179         if (ops->set_current_limit) {
2180                 status = device_create_file(dev, &dev_attr_min_microamps);
2181                 if (status < 0)
2182                         return status;
2183                 status = device_create_file(dev, &dev_attr_max_microamps);
2184                 if (status < 0)
2185                         return status;
2186         }
2187
2188         /* suspend mode constraints need multiple supporting methods */
2189         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2190                 return status;
2191
2192         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2193         if (status < 0)
2194                 return status;
2195         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2196         if (status < 0)
2197                 return status;
2198         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2199         if (status < 0)
2200                 return status;
2201
2202         if (ops->set_suspend_voltage) {
2203                 status = device_create_file(dev,
2204                                 &dev_attr_suspend_standby_microvolts);
2205                 if (status < 0)
2206                         return status;
2207                 status = device_create_file(dev,
2208                                 &dev_attr_suspend_mem_microvolts);
2209                 if (status < 0)
2210                         return status;
2211                 status = device_create_file(dev,
2212                                 &dev_attr_suspend_disk_microvolts);
2213                 if (status < 0)
2214                         return status;
2215         }
2216
2217         if (ops->set_suspend_mode) {
2218                 status = device_create_file(dev,
2219                                 &dev_attr_suspend_standby_mode);
2220                 if (status < 0)
2221                         return status;
2222                 status = device_create_file(dev,
2223                                 &dev_attr_suspend_mem_mode);
2224                 if (status < 0)
2225                         return status;
2226                 status = device_create_file(dev,
2227                                 &dev_attr_suspend_disk_mode);
2228                 if (status < 0)
2229                         return status;
2230         }
2231
2232         return status;
2233 }
2234
2235 /**
2236  * regulator_register - register regulator
2237  * @regulator_desc: regulator to register
2238  * @dev: struct device for the regulator
2239  * @init_data: platform provided init data, passed through by driver
2240  * @driver_data: private regulator data
2241  *
2242  * Called by regulator drivers to register a regulator.
2243  * Returns 0 on success.
2244  */
2245 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2246         struct device *dev, struct regulator_init_data *init_data,
2247         void *driver_data)
2248 {
2249         static atomic_t regulator_no = ATOMIC_INIT(0);
2250         struct regulator_dev *rdev;
2251         int ret, i;
2252
2253         if (regulator_desc == NULL)
2254                 return ERR_PTR(-EINVAL);
2255
2256         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2257                 return ERR_PTR(-EINVAL);
2258
2259         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2260             regulator_desc->type != REGULATOR_CURRENT)
2261                 return ERR_PTR(-EINVAL);
2262
2263         if (!init_data)
2264                 return ERR_PTR(-EINVAL);
2265
2266         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2267         if (rdev == NULL)
2268                 return ERR_PTR(-ENOMEM);
2269
2270         mutex_lock(&regulator_list_mutex);
2271
2272         mutex_init(&rdev->mutex);
2273         rdev->reg_data = driver_data;
2274         rdev->owner = regulator_desc->owner;
2275         rdev->desc = regulator_desc;
2276         INIT_LIST_HEAD(&rdev->consumer_list);
2277         INIT_LIST_HEAD(&rdev->supply_list);
2278         INIT_LIST_HEAD(&rdev->list);
2279         INIT_LIST_HEAD(&rdev->slist);
2280         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2281
2282         /* preform any regulator specific init */
2283         if (init_data->regulator_init) {
2284                 ret = init_data->regulator_init(rdev->reg_data);
2285                 if (ret < 0)
2286                         goto clean;
2287         }
2288
2289         /* register with sysfs */
2290         rdev->dev.class = &regulator_class;
2291         rdev->dev.parent = dev;
2292         dev_set_name(&rdev->dev, "regulator.%d",
2293                      atomic_inc_return(&regulator_no) - 1);
2294         ret = device_register(&rdev->dev);
2295         if (ret != 0)
2296                 goto clean;
2297
2298         dev_set_drvdata(&rdev->dev, rdev);
2299
2300         /* set regulator constraints */
2301         ret = set_machine_constraints(rdev, &init_data->constraints);
2302         if (ret < 0)
2303                 goto scrub;
2304
2305         /* add attributes supported by this regulator */
2306         ret = add_regulator_attributes(rdev);
2307         if (ret < 0)
2308                 goto scrub;
2309
2310         /* set supply regulator if it exists */
2311         if (init_data->supply_regulator_dev) {
2312                 ret = set_supply(rdev,
2313                         dev_get_drvdata(init_data->supply_regulator_dev));
2314                 if (ret < 0)
2315                         goto scrub;
2316         }
2317
2318         /* add consumers devices */
2319         for (i = 0; i < init_data->num_consumer_supplies; i++) {
2320                 ret = set_consumer_device_supply(rdev,
2321                         init_data->consumer_supplies[i].dev,
2322                         init_data->consumer_supplies[i].dev_name,
2323                         init_data->consumer_supplies[i].supply);
2324                 if (ret < 0) {
2325                         for (--i; i >= 0; i--)
2326                                 unset_consumer_device_supply(rdev,
2327                                     init_data->consumer_supplies[i].dev_name,
2328                                     init_data->consumer_supplies[i].dev);
2329                         goto scrub;
2330                 }
2331         }
2332
2333         list_add(&rdev->list, &regulator_list);
2334 out:
2335         mutex_unlock(&regulator_list_mutex);
2336         return rdev;
2337
2338 scrub:
2339         device_unregister(&rdev->dev);
2340         /* device core frees rdev */
2341         rdev = ERR_PTR(ret);
2342         goto out;
2343
2344 clean:
2345         kfree(rdev);
2346         rdev = ERR_PTR(ret);
2347         goto out;
2348 }
2349 EXPORT_SYMBOL_GPL(regulator_register);
2350
2351 /**
2352  * regulator_unregister - unregister regulator
2353  * @rdev: regulator to unregister
2354  *
2355  * Called by regulator drivers to unregister a regulator.
2356  */
2357 void regulator_unregister(struct regulator_dev *rdev)
2358 {
2359         if (rdev == NULL)
2360                 return;
2361
2362         mutex_lock(&regulator_list_mutex);
2363         WARN_ON(rdev->open_count);
2364         unset_regulator_supplies(rdev);
2365         list_del(&rdev->list);
2366         if (rdev->supply)
2367                 sysfs_remove_link(&rdev->dev.kobj, "supply");
2368         device_unregister(&rdev->dev);
2369         mutex_unlock(&regulator_list_mutex);
2370 }
2371 EXPORT_SYMBOL_GPL(regulator_unregister);
2372
2373 /**
2374  * regulator_suspend_prepare - prepare regulators for system wide suspend
2375  * @state: system suspend state
2376  *
2377  * Configure each regulator with it's suspend operating parameters for state.
2378  * This will usually be called by machine suspend code prior to supending.
2379  */
2380 int regulator_suspend_prepare(suspend_state_t state)
2381 {
2382         struct regulator_dev *rdev;
2383         int ret = 0;
2384
2385         /* ON is handled by regulator active state */
2386         if (state == PM_SUSPEND_ON)
2387                 return -EINVAL;
2388
2389         mutex_lock(&regulator_list_mutex);
2390         list_for_each_entry(rdev, &regulator_list, list) {
2391
2392                 mutex_lock(&rdev->mutex);
2393                 ret = suspend_prepare(rdev, state);
2394                 mutex_unlock(&rdev->mutex);
2395
2396                 if (ret < 0) {
2397                         printk(KERN_ERR "%s: failed to prepare %s\n",
2398                                 __func__, rdev_get_name(rdev));
2399                         goto out;
2400                 }
2401         }
2402 out:
2403         mutex_unlock(&regulator_list_mutex);
2404         return ret;
2405 }
2406 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2407
2408 /**
2409  * regulator_has_full_constraints - the system has fully specified constraints
2410  *
2411  * Calling this function will cause the regulator API to disable all
2412  * regulators which have a zero use count and don't have an always_on
2413  * constraint in a late_initcall.
2414  *
2415  * The intention is that this will become the default behaviour in a
2416  * future kernel release so users are encouraged to use this facility
2417  * now.
2418  */
2419 void regulator_has_full_constraints(void)
2420 {
2421         has_full_constraints = 1;
2422 }
2423 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2424
2425 /**
2426  * rdev_get_drvdata - get rdev regulator driver data
2427  * @rdev: regulator
2428  *
2429  * Get rdev regulator driver private data. This call can be used in the
2430  * regulator driver context.
2431  */
2432 void *rdev_get_drvdata(struct regulator_dev *rdev)
2433 {
2434         return rdev->reg_data;
2435 }
2436 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2437
2438 /**
2439  * regulator_get_drvdata - get regulator driver data
2440  * @regulator: regulator
2441  *
2442  * Get regulator driver private data. This call can be used in the consumer
2443  * driver context when non API regulator specific functions need to be called.
2444  */
2445 void *regulator_get_drvdata(struct regulator *regulator)
2446 {
2447         return regulator->rdev->reg_data;
2448 }
2449 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2450
2451 /**
2452  * regulator_set_drvdata - set regulator driver data
2453  * @regulator: regulator
2454  * @data: data
2455  */
2456 void regulator_set_drvdata(struct regulator *regulator, void *data)
2457 {
2458         regulator->rdev->reg_data = data;
2459 }
2460 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2461
2462 /**
2463  * regulator_get_id - get regulator ID
2464  * @rdev: regulator
2465  */
2466 int rdev_get_id(struct regulator_dev *rdev)
2467 {
2468         return rdev->desc->id;
2469 }
2470 EXPORT_SYMBOL_GPL(rdev_get_id);
2471
2472 struct device *rdev_get_dev(struct regulator_dev *rdev)
2473 {
2474         return &rdev->dev;
2475 }
2476 EXPORT_SYMBOL_GPL(rdev_get_dev);
2477
2478 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2479 {
2480         return reg_init_data->driver_data;
2481 }
2482 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2483
2484 static int __init regulator_init(void)
2485 {
2486         printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2487         return class_register(&regulator_class);
2488 }
2489
2490 /* init early to allow our consumers to complete system booting */
2491 core_initcall(regulator_init);
2492
2493 static int __init regulator_init_complete(void)
2494 {
2495         struct regulator_dev *rdev;
2496         struct regulator_ops *ops;
2497         struct regulation_constraints *c;
2498         int enabled, ret;
2499         const char *name;
2500
2501         mutex_lock(&regulator_list_mutex);
2502
2503         /* If we have a full configuration then disable any regulators
2504          * which are not in use or always_on.  This will become the
2505          * default behaviour in the future.
2506          */
2507         list_for_each_entry(rdev, &regulator_list, list) {
2508                 ops = rdev->desc->ops;
2509                 c = rdev->constraints;
2510
2511                 name = rdev_get_name(rdev);
2512
2513                 if (!ops->disable || (c && c->always_on))
2514                         continue;
2515
2516                 mutex_lock(&rdev->mutex);
2517
2518                 if (rdev->use_count)
2519                         goto unlock;
2520
2521                 /* If we can't read the status assume it's on. */
2522                 if (ops->is_enabled)
2523                         enabled = ops->is_enabled(rdev);
2524                 else
2525                         enabled = 1;
2526
2527                 if (!enabled)
2528                         goto unlock;
2529
2530                 if (has_full_constraints) {
2531                         /* We log since this may kill the system if it
2532                          * goes wrong. */
2533                         printk(KERN_INFO "%s: disabling %s\n",
2534                                __func__, name);
2535                         ret = ops->disable(rdev);
2536                         if (ret != 0) {
2537                                 printk(KERN_ERR
2538                                        "%s: couldn't disable %s: %d\n",
2539                                        __func__, name, ret);
2540                         }
2541                 } else {
2542                         /* The intention is that in future we will
2543                          * assume that full constraints are provided
2544                          * so warn even if we aren't going to do
2545                          * anything here.
2546                          */
2547                         printk(KERN_WARNING
2548                                "%s: incomplete constraints, leaving %s on\n",
2549                                __func__, name);
2550                 }
2551
2552 unlock:
2553                 mutex_unlock(&rdev->mutex);
2554         }
2555
2556         mutex_unlock(&regulator_list_mutex);
2557
2558         return 0;
2559 }
2560 late_initcall(regulator_init_complete);