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/regulator/consumer.h>
  23 #include <linux/regulator/driver.h>
  24 #include <linux/regulator/machine.h>
  25
  26 #define REGULATOR_VERSION "0.5"
  27
  28 static DEFINE_MUTEX(regulator_list_mutex);
  29 static LIST_HEAD(regulator_list);
  30 static LIST_HEAD(regulator_map_list);
  31
  32 /**
  33  * struct regulator_dev
  34  *
  35  * Voltage / Current regulator class device. One for each regulator.
  36  */
  37 struct regulator_dev {
  38         struct regulator_desc *desc;
  39         int use_count;
  40
  41         /* lists we belong to */
  42         struct list_head list; /* list of all regulators */
  43         struct list_head slist; /* list of supplied regulators */
  44
  45         /* lists we own */
  46         struct list_head consumer_list; /* consumers we supply */
  47         struct list_head supply_list; /* regulators we supply */
  48
  49         struct blocking_notifier_head notifier;
  50         struct mutex mutex; /* consumer lock */
  51         struct module *owner;
  52         struct device dev;
  53         struct regulation_constraints *constraints;
  54         struct regulator_dev *supply;   /* for tree */
  55
  56         void *reg_data;         /* regulator_dev data */
  57 };
  58
  59 /**
  60  * struct regulator_map
  61  *
  62  * Used to provide symbolic supply names to devices.
  63  */
  64 struct regulator_map {
  65         struct list_head list;
  66         struct device *dev;
  67         const char *supply;
  68         struct regulator_dev *regulator;
  69 };
  70
  71 /*
  72  * struct regulator
  73  *
  74  * One for each consumer device.
  75  */
  76 struct regulator {
  77         struct device *dev;
  78         struct list_head list;
  79         int uA_load;
  80         int min_uV;
  81         int max_uV;
  82         int enabled; /* count of client enables */
  83         char *supply_name;
  84         struct device_attribute dev_attr;
  85         struct regulator_dev *rdev;
  86 };
  87
  88 static int _regulator_is_enabled(struct regulator_dev *rdev);
  89 static int _regulator_disable(struct regulator_dev *rdev);
  90 static int _regulator_get_voltage(struct regulator_dev *rdev);
  91 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  92 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  93 static void _notifier_call_chain(struct regulator_dev *rdev,
  94                                   unsigned long event, void *data);
  95
  96 /* gets the regulator for a given consumer device */
  97 static struct regulator *get_device_regulator(struct device *dev)
  98 {
  99         struct regulator *regulator = NULL;
 100         struct regulator_dev *rdev;
 101
 102         mutex_lock(&regulator_list_mutex);
 103         list_for_each_entry(rdev, &regulator_list, list) {
 104                 mutex_lock(&rdev->mutex);
 105                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
 106                         if (regulator->dev == dev) {
 107                                 mutex_unlock(&rdev->mutex);
 108                                 mutex_unlock(&regulator_list_mutex);
 109                                 return regulator;
 110                         }
 111                 }
 112                 mutex_unlock(&rdev->mutex);
 113         }
 114         mutex_unlock(&regulator_list_mutex);
 115         return NULL;
 116 }
 117
 118 /* Platform voltage constraint check */
 119 static int regulator_check_voltage(struct regulator_dev *rdev,
 120                                    int *min_uV, int *max_uV)
 121 {
 122         BUG_ON(*min_uV > *max_uV);
 123
 124         if (!rdev->constraints) {
 125                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 126                        rdev->desc->name);
 127                 return -ENODEV;
 128         }
 129         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 130                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 131                        __func__, rdev->desc->name);
 132                 return -EPERM;
 133         }
 134
 135         if (*max_uV > rdev->constraints->max_uV)
 136                 *max_uV = rdev->constraints->max_uV;
 137         if (*min_uV < rdev->constraints->min_uV)
 138                 *min_uV = rdev->constraints->min_uV;
 139
 140         if (*min_uV > *max_uV)
 141                 return -EINVAL;
 142
 143         return 0;
 144 }
 145
 146 /* current constraint check */
 147 static int regulator_check_current_limit(struct regulator_dev *rdev,
 148                                         int *min_uA, int *max_uA)
 149 {
 150         BUG_ON(*min_uA > *max_uA);
 151
 152         if (!rdev->constraints) {
 153                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 154                        rdev->desc->name);
 155                 return -ENODEV;
 156         }
 157         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 158                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 159                        __func__, rdev->desc->name);
 160                 return -EPERM;
 161         }
 162
 163         if (*max_uA > rdev->constraints->max_uA)
 164                 *max_uA = rdev->constraints->max_uA;
 165         if (*min_uA < rdev->constraints->min_uA)
 166                 *min_uA = rdev->constraints->min_uA;
 167
 168         if (*min_uA > *max_uA)
 169                 return -EINVAL;
 170
 171         return 0;
 172 }
 173
 174 /* operating mode constraint check */
 175 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
 176 {
 177         switch (mode) {
 178         case REGULATOR_MODE_FAST:
 179         case REGULATOR_MODE_NORMAL:
 180         case REGULATOR_MODE_IDLE:
 181         case REGULATOR_MODE_STANDBY:
 182                 break;
 183         default:
 184                 return -EINVAL;
 185         }
 186
 187         if (!rdev->constraints) {
 188                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 189                        rdev->desc->name);
 190                 return -ENODEV;
 191         }
 192         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 193                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 194                        __func__, rdev->desc->name);
 195                 return -EPERM;
 196         }
 197         if (!(rdev->constraints->valid_modes_mask & mode)) {
 198                 printk(KERN_ERR "%s: invalid mode %x for %s\n",
 199                        __func__, mode, rdev->desc->name);
 200                 return -EINVAL;
 201         }
 202         return 0;
 203 }
 204
 205 /* dynamic regulator mode switching constraint check */
 206 static int regulator_check_drms(struct regulator_dev *rdev)
 207 {
 208         if (!rdev->constraints) {
 209                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 210                        rdev->desc->name);
 211                 return -ENODEV;
 212         }
 213         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 214                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 215                        __func__, rdev->desc->name);
 216                 return -EPERM;
 217         }
 218         return 0;
 219 }
 220
 221 static ssize_t device_requested_uA_show(struct device *dev,
 222                              struct device_attribute *attr, char *buf)
 223 {
 224         struct regulator *regulator;
 225
 226         regulator = get_device_regulator(dev);
 227         if (regulator == NULL)
 228                 return 0;
 229
 230         return sprintf(buf, "%d\n", regulator->uA_load);
 231 }
 232
 233 static ssize_t regulator_uV_show(struct device *dev,
 234                                 struct device_attribute *attr, char *buf)
 235 {
 236         struct regulator_dev *rdev = dev_get_drvdata(dev);
 237         ssize_t ret;
 238
 239         mutex_lock(&rdev->mutex);
 240         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 241         mutex_unlock(&rdev->mutex);
 242
 243         return ret;
 244 }
 245
 246 static ssize_t regulator_uA_show(struct device *dev,
 247                                 struct device_attribute *attr, char *buf)
 248 {
 249         struct regulator_dev *rdev = dev_get_drvdata(dev);
 250
 251         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 252 }
 253
 254 static ssize_t regulator_name_show(struct device *dev,
 255                              struct device_attribute *attr, char *buf)
 256 {
 257         struct regulator_dev *rdev = dev_get_drvdata(dev);
 258         const char *name;
 259
 260         if (rdev->constraints->name)
 261                 name = rdev->constraints->name;
 262         else if (rdev->desc->name)
 263                 name = rdev->desc->name;
 264         else
 265                 name = "";
 266
 267         return sprintf(buf, "%s\n", name);
 268 }
 269
 270 static ssize_t regulator_print_opmode(char *buf, int mode)
 271 {
 272         switch (mode) {
 273         case REGULATOR_MODE_FAST:
 274                 return sprintf(buf, "fast\n");
 275         case REGULATOR_MODE_NORMAL:
 276                 return sprintf(buf, "normal\n");
 277         case REGULATOR_MODE_IDLE:
 278                 return sprintf(buf, "idle\n");
 279         case REGULATOR_MODE_STANDBY:
 280                 return sprintf(buf, "standby\n");
 281         }
 282         return sprintf(buf, "unknown\n");
 283 }
 284
 285 static ssize_t regulator_opmode_show(struct device *dev,
 286                                     struct device_attribute *attr, char *buf)
 287 {
 288         struct regulator_dev *rdev = dev_get_drvdata(dev);
 289
 290         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 291 }
 292
 293 static ssize_t regulator_print_state(char *buf, int state)
 294 {
 295         if (state > 0)
 296                 return sprintf(buf, "enabled\n");
 297         else if (state == 0)
 298                 return sprintf(buf, "disabled\n");
 299         else
 300                 return sprintf(buf, "unknown\n");
 301 }
 302
 303 static ssize_t regulator_state_show(struct device *dev,
 304                                    struct device_attribute *attr, char *buf)
 305 {
 306         struct regulator_dev *rdev = dev_get_drvdata(dev);
 307
 308         return regulator_print_state(buf, _regulator_is_enabled(rdev));
 309 }
 310
 311 static ssize_t regulator_min_uA_show(struct device *dev,
 312                                     struct device_attribute *attr, char *buf)
 313 {
 314         struct regulator_dev *rdev = dev_get_drvdata(dev);
 315
 316         if (!rdev->constraints)
 317                 return sprintf(buf, "constraint not defined\n");
 318
 319         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 320 }
 321
 322 static ssize_t regulator_max_uA_show(struct device *dev,
 323                                     struct device_attribute *attr, char *buf)
 324 {
 325         struct regulator_dev *rdev = dev_get_drvdata(dev);
 326
 327         if (!rdev->constraints)
 328                 return sprintf(buf, "constraint not defined\n");
 329
 330         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 331 }
 332
 333 static ssize_t regulator_min_uV_show(struct device *dev,
 334                                     struct device_attribute *attr, char *buf)
 335 {
 336         struct regulator_dev *rdev = dev_get_drvdata(dev);
 337
 338         if (!rdev->constraints)
 339                 return sprintf(buf, "constraint not defined\n");
 340
 341         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 342 }
 343
 344 static ssize_t regulator_max_uV_show(struct device *dev,
 345                                     struct device_attribute *attr, char *buf)
 346 {
 347         struct regulator_dev *rdev = dev_get_drvdata(dev);
 348
 349         if (!rdev->constraints)
 350                 return sprintf(buf, "constraint not defined\n");
 351
 352         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 353 }
 354
 355 static ssize_t regulator_total_uA_show(struct device *dev,
 356                                       struct device_attribute *attr, char *buf)
 357 {
 358         struct regulator_dev *rdev = dev_get_drvdata(dev);
 359         struct regulator *regulator;
 360         int uA = 0;
 361
 362         mutex_lock(&rdev->mutex);
 363         list_for_each_entry(regulator, &rdev->consumer_list, list)
 364             uA += regulator->uA_load;
 365         mutex_unlock(&rdev->mutex);
 366         return sprintf(buf, "%d\n", uA);
 367 }
 368
 369 static ssize_t regulator_num_users_show(struct device *dev,
 370                                       struct device_attribute *attr, char *buf)
 371 {
 372         struct regulator_dev *rdev = dev_get_drvdata(dev);
 373         return sprintf(buf, "%d\n", rdev->use_count);
 374 }
 375
 376 static ssize_t regulator_type_show(struct device *dev,
 377                                   struct device_attribute *attr, char *buf)
 378 {
 379         struct regulator_dev *rdev = dev_get_drvdata(dev);
 380
 381         switch (rdev->desc->type) {
 382         case REGULATOR_VOLTAGE:
 383                 return sprintf(buf, "voltage\n");
 384         case REGULATOR_CURRENT:
 385                 return sprintf(buf, "current\n");
 386         }
 387         return sprintf(buf, "unknown\n");
 388 }
 389
 390 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 391                                 struct device_attribute *attr, char *buf)
 392 {
 393         struct regulator_dev *rdev = dev_get_drvdata(dev);
 394
 395         if (!rdev->constraints)
 396                 return sprintf(buf, "not defined\n");
 397         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 398 }
 399
 400 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 401                                 struct device_attribute *attr, char *buf)
 402 {
 403         struct regulator_dev *rdev = dev_get_drvdata(dev);
 404
 405         if (!rdev->constraints)
 406                 return sprintf(buf, "not defined\n");
 407         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 408 }
 409
 410 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 411                                 struct device_attribute *attr, char *buf)
 412 {
 413         struct regulator_dev *rdev = dev_get_drvdata(dev);
 414
 415         if (!rdev->constraints)
 416                 return sprintf(buf, "not defined\n");
 417         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 418 }
 419
 420 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 421                                 struct device_attribute *attr, char *buf)
 422 {
 423         struct regulator_dev *rdev = dev_get_drvdata(dev);
 424
 425         if (!rdev->constraints)
 426                 return sprintf(buf, "not defined\n");
 427         return regulator_print_opmode(buf,
 428                 rdev->constraints->state_mem.mode);
 429 }
 430
 431 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 432                                 struct device_attribute *attr, char *buf)
 433 {
 434         struct regulator_dev *rdev = dev_get_drvdata(dev);
 435
 436         if (!rdev->constraints)
 437                 return sprintf(buf, "not defined\n");
 438         return regulator_print_opmode(buf,
 439                 rdev->constraints->state_disk.mode);
 440 }
 441
 442 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 443                                 struct device_attribute *attr, char *buf)
 444 {
 445         struct regulator_dev *rdev = dev_get_drvdata(dev);
 446
 447         if (!rdev->constraints)
 448                 return sprintf(buf, "not defined\n");
 449         return regulator_print_opmode(buf,
 450                 rdev->constraints->state_standby.mode);
 451 }
 452
 453 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 454                                    struct device_attribute *attr, char *buf)
 455 {
 456         struct regulator_dev *rdev = dev_get_drvdata(dev);
 457
 458         if (!rdev->constraints)
 459                 return sprintf(buf, "not defined\n");
 460
 461         return regulator_print_state(buf,
 462                         rdev->constraints->state_mem.enabled);
 463 }
 464
 465 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 466                                    struct device_attribute *attr, char *buf)
 467 {
 468         struct regulator_dev *rdev = dev_get_drvdata(dev);
 469
 470         if (!rdev->constraints)
 471                 return sprintf(buf, "not defined\n");
 472
 473         return regulator_print_state(buf,
 474                         rdev->constraints->state_disk.enabled);
 475 }
 476
 477 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 478                                    struct device_attribute *attr, char *buf)
 479 {
 480         struct regulator_dev *rdev = dev_get_drvdata(dev);
 481
 482         if (!rdev->constraints)
 483                 return sprintf(buf, "not defined\n");
 484
 485         return regulator_print_state(buf,
 486                         rdev->constraints->state_standby.enabled);
 487 }
 488
 489 static struct device_attribute regulator_dev_attrs[] = {
 490         __ATTR(name, 0444, regulator_name_show, NULL),
 491         __ATTR(microvolts, 0444, regulator_uV_show, NULL),
 492         __ATTR(microamps, 0444, regulator_uA_show, NULL),
 493         __ATTR(opmode, 0444, regulator_opmode_show, NULL),
 494         __ATTR(state, 0444, regulator_state_show, NULL),
 495         __ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL),
 496         __ATTR(min_microamps, 0444, regulator_min_uA_show, NULL),
 497         __ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL),
 498         __ATTR(max_microamps, 0444, regulator_max_uA_show, NULL),
 499         __ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL),
 500         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
 501         __ATTR(type, 0444, regulator_type_show, NULL),
 502         __ATTR(suspend_mem_microvolts, 0444,
 503                 regulator_suspend_mem_uV_show, NULL),
 504         __ATTR(suspend_disk_microvolts, 0444,
 505                 regulator_suspend_disk_uV_show, NULL),
 506         __ATTR(suspend_standby_microvolts, 0444,
 507                 regulator_suspend_standby_uV_show, NULL),
 508         __ATTR(suspend_mem_mode, 0444,
 509                 regulator_suspend_mem_mode_show, NULL),
 510         __ATTR(suspend_disk_mode, 0444,
 511                 regulator_suspend_disk_mode_show, NULL),
 512         __ATTR(suspend_standby_mode, 0444,
 513                 regulator_suspend_standby_mode_show, NULL),
 514         __ATTR(suspend_mem_state, 0444,
 515                 regulator_suspend_mem_state_show, NULL),
 516         __ATTR(suspend_disk_state, 0444,
 517                 regulator_suspend_disk_state_show, NULL),
 518         __ATTR(suspend_standby_state, 0444,
 519                 regulator_suspend_standby_state_show, NULL),
 520         __ATTR_NULL,
 521 };
 522
 523 static void regulator_dev_release(struct device *dev)
 524 {
 525         struct regulator_dev *rdev = dev_get_drvdata(dev);
 526         kfree(rdev);
 527 }
 528
 529 static struct class regulator_class = {
 530         .name = "regulator",
 531         .dev_release = regulator_dev_release,
 532         .dev_attrs = regulator_dev_attrs,
 533 };
 534
 535 /* Calculate the new optimum regulator operating mode based on the new total
 536  * consumer load. All locks held by caller */
 537 static void drms_uA_update(struct regulator_dev *rdev)
 538 {
 539         struct regulator *sibling;
 540         int current_uA = 0, output_uV, input_uV, err;
 541         unsigned int mode;
 542
 543         err = regulator_check_drms(rdev);
 544         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 545             !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode);
 546         return;
 547
 548         /* get output voltage */
 549         output_uV = rdev->desc->ops->get_voltage(rdev);
 550         if (output_uV <= 0)
 551                 return;
 552
 553         /* get input voltage */
 554         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
 555                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
 556         else
 557                 input_uV = rdev->constraints->input_uV;
 558         if (input_uV <= 0)
 559                 return;
 560
 561         /* calc total requested load */
 562         list_for_each_entry(sibling, &rdev->consumer_list, list)
 563             current_uA += sibling->uA_load;
 564
 565         /* now get the optimum mode for our new total regulator load */
 566         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 567                                                   output_uV, current_uA);
 568
 569         /* check the new mode is allowed */
 570         err = regulator_check_mode(rdev, mode);
 571         if (err == 0)
 572                 rdev->desc->ops->set_mode(rdev, mode);
 573 }
 574
 575 static int suspend_set_state(struct regulator_dev *rdev,
 576         struct regulator_state *rstate)
 577 {
 578         int ret = 0;
 579
 580         /* enable & disable are mandatory for suspend control */
 581         if (!rdev->desc->ops->set_suspend_enable ||
 582                 !rdev->desc->ops->set_suspend_disable) {
 583                 printk(KERN_ERR "%s: no way to set suspend state\n",
 584                         __func__);
 585                 return -EINVAL;
 586         }
 587
 588         if (rstate->enabled)
 589                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 590         else
 591                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 592         if (ret < 0) {
 593                 printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
 594                 return ret;
 595         }
 596
 597         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 598                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 599                 if (ret < 0) {
 600                         printk(KERN_ERR "%s: failed to set voltage\n",
 601                                 __func__);
 602                         return ret;
 603                 }
 604         }
 605
 606         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 607                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 608                 if (ret < 0) {
 609                         printk(KERN_ERR "%s: failed to set mode\n", __func__);
 610                         return ret;
 611                 }
 612         }
 613         return ret;
 614 }
 615
 616 /* locks held by caller */
 617 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 618 {
 619         if (!rdev->constraints)
 620                 return -EINVAL;
 621
 622         switch (state) {
 623         case PM_SUSPEND_STANDBY:
 624                 return suspend_set_state(rdev,
 625                         &rdev->constraints->state_standby);
 626         case PM_SUSPEND_MEM:
 627                 return suspend_set_state(rdev,
 628                         &rdev->constraints->state_mem);
 629         case PM_SUSPEND_MAX:
 630                 return suspend_set_state(rdev,
 631                         &rdev->constraints->state_disk);
 632         default:
 633                 return -EINVAL;
 634         }
 635 }
 636
 637 static void print_constraints(struct regulator_dev *rdev)
 638 {
 639         struct regulation_constraints *constraints = rdev->constraints;
 640         char buf[80];
 641         int count;
 642
 643         if (rdev->desc->type == REGULATOR_VOLTAGE) {
 644                 if (constraints->min_uV == constraints->max_uV)
 645                         count = sprintf(buf, "%d mV ",
 646                                         constraints->min_uV / 1000);
 647                 else
 648                         count = sprintf(buf, "%d <--> %d mV ",
 649                                         constraints->min_uV / 1000,
 650                                         constraints->max_uV / 1000);
 651         } else {
 652                 if (constraints->min_uA == constraints->max_uA)
 653                         count = sprintf(buf, "%d mA ",
 654                                         constraints->min_uA / 1000);
 655                 else
 656                         count = sprintf(buf, "%d <--> %d mA ",
 657                                         constraints->min_uA / 1000,
 658                                         constraints->max_uA / 1000);
 659         }
 660         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 661                 count += sprintf(buf + count, "fast ");
 662         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 663                 count += sprintf(buf + count, "normal ");
 664         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 665                 count += sprintf(buf + count, "idle ");
 666         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 667                 count += sprintf(buf + count, "standby");
 668
 669         printk(KERN_INFO "regulator: %s: %s\n", rdev->desc->name, buf);
 670 }
 671
 672 /**
 673  * set_machine_constraints - sets regulator constraints
 674  * @regulator: regulator source
 675  *
 676  * Allows platform initialisation code to define and constrain
 677  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 678  * Constraints *must* be set by platform code in order for some
 679  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 680  * set_mode.
 681  */
 682 static int set_machine_constraints(struct regulator_dev *rdev,
 683         struct regulation_constraints *constraints)
 684 {
 685         int ret = 0;
 686         const char *name;
 687         struct regulator_ops *ops = rdev->desc->ops;
 688
 689         if (constraints->name)
 690                 name = constraints->name;
 691         else if (rdev->desc->name)
 692                 name = rdev->desc->name;
 693         else
 694                 name = "regulator";
 695
 696         rdev->constraints = constraints;
 697
 698         /* do we need to apply the constraint voltage */
 699         if (rdev->constraints->apply_uV &&
 700                 rdev->constraints->min_uV == rdev->constraints->max_uV &&
 701                 ops->set_voltage) {
 702                 ret = ops->set_voltage(rdev,
 703                         rdev->constraints->min_uV, rdev->constraints->max_uV);
 704                         if (ret < 0) {
 705                                 printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
 706                                        __func__,
 707                                        rdev->constraints->min_uV, name);
 708                                 rdev->constraints = NULL;
 709                                 goto out;
 710                         }
 711         }
 712
 713         /* are we enabled at boot time by firmware / bootloader */
 714         if (rdev->constraints->boot_on)
 715                 rdev->use_count = 1;
 716
 717         /* do we need to setup our suspend state */
 718         if (constraints->initial_state) {
 719                 ret = suspend_prepare(rdev, constraints->initial_state);
 720                 if (ret < 0) {
 721                         printk(KERN_ERR "%s: failed to set suspend state for %s\n",
 722                                __func__, name);
 723                         rdev->constraints = NULL;
 724                         goto out;
 725                 }
 726         }
 727
 728         /* if always_on is set then turn the regulator on if it's not
 729          * already on. */
 730         if (constraints->always_on && ops->enable &&
 731             ((ops->is_enabled && !ops->is_enabled(rdev)) ||
 732              (!ops->is_enabled && !constraints->boot_on))) {
 733                 ret = ops->enable(rdev);
 734                 if (ret < 0) {
 735                         printk(KERN_ERR "%s: failed to enable %s\n",
 736                                __func__, name);
 737                         rdev->constraints = NULL;
 738                         goto out;
 739                 }
 740         }
 741
 742         print_constraints(rdev);
 743 out:
 744         return ret;
 745 }
 746
 747 /**
 748  * set_supply - set regulator supply regulator
 749  * @regulator: regulator name
 750  * @supply: supply regulator name
 751  *
 752  * Called by platform initialisation code to set the supply regulator for this
 753  * regulator. This ensures that a regulators supply will also be enabled by the
 754  * core if it's child is enabled.
 755  */
 756 static int set_supply(struct regulator_dev *rdev,
 757         struct regulator_dev *supply_rdev)
 758 {
 759         int err;
 760
 761         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
 762                                 "supply");
 763         if (err) {
 764                 printk(KERN_ERR
 765                        "%s: could not add device link %s err %d\n",
 766                        __func__, supply_rdev->dev.kobj.name, err);
 767                        goto out;
 768         }
 769         rdev->supply = supply_rdev;
 770         list_add(&rdev->slist, &supply_rdev->supply_list);
 771 out:
 772         return err;
 773 }
 774
 775 /**
 776  * set_consumer_device_supply: Bind a regulator to a symbolic supply
 777  * @regulator: regulator source
 778  * @dev:       device the supply applies to
 779  * @supply:    symbolic name for supply
 780  *
 781  * Allows platform initialisation code to map physical regulator
 782  * sources to symbolic names for supplies for use by devices.  Devices
 783  * should use these symbolic names to request regulators, avoiding the
 784  * need to provide board-specific regulator names as platform data.
 785  */
 786 static int set_consumer_device_supply(struct regulator_dev *rdev,
 787         struct device *consumer_dev, const char *supply)
 788 {
 789         struct regulator_map *node;
 790
 791         if (supply == NULL)
 792                 return -EINVAL;
 793
 794         node = kmalloc(sizeof(struct regulator_map), GFP_KERNEL);
 795         if (node == NULL)
 796                 return -ENOMEM;
 797
 798         node->regulator = rdev;
 799         node->dev = consumer_dev;
 800         node->supply = supply;
 801
 802         list_add(&node->list, &regulator_map_list);
 803         return 0;
 804 }
 805
 806 static void unset_consumer_device_supply(struct regulator_dev *rdev,
 807         struct device *consumer_dev)
 808 {
 809         struct regulator_map *node, *n;
 810
 811         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
 812                 if (rdev == node->regulator &&
 813                         consumer_dev == node->dev) {
 814                         list_del(&node->list);
 815                         kfree(node);
 816                         return;
 817                 }
 818         }
 819 }
 820
 821 #define REG_STR_SIZE    32
 822
 823 static struct regulator *create_regulator(struct regulator_dev *rdev,
 824                                           struct device *dev,
 825                                           const char *supply_name)
 826 {
 827         struct regulator *regulator;
 828         char buf[REG_STR_SIZE];
 829         int err, size;
 830
 831         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
 832         if (regulator == NULL)
 833                 return NULL;
 834
 835         mutex_lock(&rdev->mutex);
 836         regulator->rdev = rdev;
 837         list_add(&regulator->list, &rdev->consumer_list);
 838
 839         if (dev) {
 840                 /* create a 'requested_microamps_name' sysfs entry */
 841                 size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
 842                         supply_name);
 843                 if (size >= REG_STR_SIZE)
 844                         goto overflow_err;
 845
 846                 regulator->dev = dev;
 847                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
 848                 if (regulator->dev_attr.attr.name == NULL)
 849                         goto attr_name_err;
 850
 851                 regulator->dev_attr.attr.owner = THIS_MODULE;
 852                 regulator->dev_attr.attr.mode = 0444;
 853                 regulator->dev_attr.show = device_requested_uA_show;
 854                 err = device_create_file(dev, &regulator->dev_attr);
 855                 if (err < 0) {
 856                         printk(KERN_WARNING "%s: could not add regulator_dev"
 857                                 " load sysfs\n", __func__);
 858                         goto attr_name_err;
 859                 }
 860
 861                 /* also add a link to the device sysfs entry */
 862                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
 863                                  dev->kobj.name, supply_name);
 864                 if (size >= REG_STR_SIZE)
 865                         goto attr_err;
 866
 867                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
 868                 if (regulator->supply_name == NULL)
 869                         goto attr_err;
 870
 871                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
 872                                         buf);
 873                 if (err) {
 874                         printk(KERN_WARNING
 875                                "%s: could not add device link %s err %d\n",
 876                                __func__, dev->kobj.name, err);
 877                         device_remove_file(dev, &regulator->dev_attr);
 878                         goto link_name_err;
 879                 }
 880         }
 881         mutex_unlock(&rdev->mutex);
 882         return regulator;
 883 link_name_err:
 884         kfree(regulator->supply_name);
 885 attr_err:
 886         device_remove_file(regulator->dev, &regulator->dev_attr);
 887 attr_name_err:
 888         kfree(regulator->dev_attr.attr.name);
 889 overflow_err:
 890         list_del(&regulator->list);
 891         kfree(regulator);
 892         mutex_unlock(&rdev->mutex);
 893         return NULL;
 894 }
 895
 896 /**
 897  * regulator_get - lookup and obtain a reference to a regulator.
 898  * @dev: device for regulator "consumer"
 899  * @id: Supply name or regulator ID.
 900  *
 901  * Returns a struct regulator corresponding to the regulator producer,
 902  * or IS_ERR() condition containing errno.  Use of supply names
 903  * configured via regulator_set_device_supply() is strongly
 904  * encouraged.
 905  */
 906 struct regulator *regulator_get(struct device *dev, const char *id)
 907 {
 908         struct regulator_dev *rdev;
 909         struct regulator_map *map;
 910         struct regulator *regulator = ERR_PTR(-ENODEV);
 911
 912         if (id == NULL) {
 913                 printk(KERN_ERR "regulator: get() with no identifier\n");
 914                 return regulator;
 915         }
 916
 917         mutex_lock(&regulator_list_mutex);
 918
 919         list_for_each_entry(map, &regulator_map_list, list) {
 920                 if (dev == map->dev &&
 921                     strcmp(map->supply, id) == 0) {
 922                         rdev = map->regulator;
 923                         goto found;
 924                 }
 925         }
 926         printk(KERN_ERR "regulator: Unable to get requested regulator: %s\n",
 927                id);
 928         mutex_unlock(&regulator_list_mutex);
 929         return regulator;
 930
 931 found:
 932         if (!try_module_get(rdev->owner))
 933                 goto out;
 934
 935         regulator = create_regulator(rdev, dev, id);
 936         if (regulator == NULL) {
 937                 regulator = ERR_PTR(-ENOMEM);
 938                 module_put(rdev->owner);
 939         }
 940
 941 out:
 942         mutex_unlock(&regulator_list_mutex);
 943         return regulator;
 944 }
 945 EXPORT_SYMBOL_GPL(regulator_get);
 946
 947 /**
 948  * regulator_put - "free" the regulator source
 949  * @regulator: regulator source
 950  *
 951  * Note: drivers must ensure that all regulator_enable calls made on this
 952  * regulator source are balanced by regulator_disable calls prior to calling
 953  * this function.
 954  */
 955 void regulator_put(struct regulator *regulator)
 956 {
 957         struct regulator_dev *rdev;
 958
 959         if (regulator == NULL || IS_ERR(regulator))
 960                 return;
 961
 962         mutex_lock(&regulator_list_mutex);
 963         rdev = regulator->rdev;
 964
 965         if (WARN(regulator->enabled, "Releasing supply %s while enabled\n",
 966                                regulator->supply_name))
 967                 _regulator_disable(rdev);
 968
 969         /* remove any sysfs entries */
 970         if (regulator->dev) {
 971                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
 972                 kfree(regulator->supply_name);
 973                 device_remove_file(regulator->dev, &regulator->dev_attr);
 974                 kfree(regulator->dev_attr.attr.name);
 975         }
 976         list_del(&regulator->list);
 977         kfree(regulator);
 978
 979         module_put(rdev->owner);
 980         mutex_unlock(&regulator_list_mutex);
 981 }
 982 EXPORT_SYMBOL_GPL(regulator_put);
 983
 984 /* locks held by regulator_enable() */
 985 static int _regulator_enable(struct regulator_dev *rdev)
 986 {
 987         int ret = -EINVAL;
 988
 989         if (!rdev->constraints) {
 990                 printk(KERN_ERR "%s: %s has no constraints\n",
 991                        __func__, rdev->desc->name);
 992                 return ret;
 993         }
 994
 995         /* do we need to enable the supply regulator first */
 996         if (rdev->supply) {
 997                 ret = _regulator_enable(rdev->supply);
 998                 if (ret < 0) {
 999                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1000                                __func__, rdev->desc->name, ret);
1001                         return ret;
1002                 }
1003         }
1004
1005         /* check voltage and requested load before enabling */
1006         if (rdev->desc->ops->enable) {
1007
1008                 if (rdev->constraints &&
1009                         (rdev->constraints->valid_ops_mask &
1010                         REGULATOR_CHANGE_DRMS))
1011                         drms_uA_update(rdev);
1012
1013                 ret = rdev->desc->ops->enable(rdev);
1014                 if (ret < 0) {
1015                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1016                                __func__, rdev->desc->name, ret);
1017                         return ret;
1018                 }
1019                 rdev->use_count++;
1020                 return ret;
1021         }
1022
1023         return ret;
1024 }
1025
1026 /**
1027  * regulator_enable - enable regulator output
1028  * @regulator: regulator source
1029  *
1030  * Enable the regulator output at the predefined voltage or current value.
1031  * NOTE: the output value can be set by other drivers, boot loader or may be
1032  * hardwired in the regulator.
1033  * NOTE: calls to regulator_enable() must be balanced with calls to
1034  * regulator_disable().
1035  */
1036 int regulator_enable(struct regulator *regulator)
1037 {
1038         struct regulator_dev *rdev = regulator->rdev;
1039         int ret = 0;
1040
1041         mutex_lock(&rdev->mutex);
1042         if (regulator->enabled == 0)
1043                 ret = _regulator_enable(rdev);
1044         else if (regulator->enabled < 0)
1045                 ret = -EIO;
1046         if (ret == 0)
1047                 regulator->enabled++;
1048         mutex_unlock(&rdev->mutex);
1049         return ret;
1050 }
1051 EXPORT_SYMBOL_GPL(regulator_enable);
1052
1053 /* locks held by regulator_disable() */
1054 static int _regulator_disable(struct regulator_dev *rdev)
1055 {
1056         int ret = 0;
1057
1058         /* are we the last user and permitted to disable ? */
1059         if (rdev->use_count == 1 && !rdev->constraints->always_on) {
1060
1061                 /* we are last user */
1062                 if (rdev->desc->ops->disable) {
1063                         ret = rdev->desc->ops->disable(rdev);
1064                         if (ret < 0) {
1065                                 printk(KERN_ERR "%s: failed to disable %s\n",
1066                                        __func__, rdev->desc->name);
1067                                 return ret;
1068                         }
1069                 }
1070
1071                 /* decrease our supplies ref count and disable if required */
1072                 if (rdev->supply)
1073                         _regulator_disable(rdev->supply);
1074
1075                 rdev->use_count = 0;
1076         } else if (rdev->use_count > 1) {
1077
1078                 if (rdev->constraints &&
1079                         (rdev->constraints->valid_ops_mask &
1080                         REGULATOR_CHANGE_DRMS))
1081                         drms_uA_update(rdev);
1082
1083                 rdev->use_count--;
1084         }
1085         return ret;
1086 }
1087
1088 /**
1089  * regulator_disable - disable regulator output
1090  * @regulator: regulator source
1091  *
1092  * Disable the regulator output voltage or current.
1093  * NOTE: this will only disable the regulator output if no other consumer
1094  * devices have it enabled.
1095  * NOTE: calls to regulator_enable() must be balanced with calls to
1096  * regulator_disable().
1097  */
1098 int regulator_disable(struct regulator *regulator)
1099 {
1100         struct regulator_dev *rdev = regulator->rdev;
1101         int ret = 0;
1102
1103         mutex_lock(&rdev->mutex);
1104         if (regulator->enabled == 1) {
1105                 ret = _regulator_disable(rdev);
1106                 if (ret == 0)
1107                         regulator->uA_load = 0;
1108         } else if (WARN(regulator->enabled <= 0,
1109                         "unbalanced disables for supply %s\n",
1110                         regulator->supply_name))
1111                 ret = -EIO;
1112         if (ret == 0)
1113                 regulator->enabled--;
1114         mutex_unlock(&rdev->mutex);
1115         return ret;
1116 }
1117 EXPORT_SYMBOL_GPL(regulator_disable);
1118
1119 /* locks held by regulator_force_disable() */
1120 static int _regulator_force_disable(struct regulator_dev *rdev)
1121 {
1122         int ret = 0;
1123
1124         /* force disable */
1125         if (rdev->desc->ops->disable) {
1126                 /* ah well, who wants to live forever... */
1127                 ret = rdev->desc->ops->disable(rdev);
1128                 if (ret < 0) {
1129                         printk(KERN_ERR "%s: failed to force disable %s\n",
1130                                __func__, rdev->desc->name);
1131                         return ret;
1132                 }
1133                 /* notify other consumers that power has been forced off */
1134                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE,
1135                         NULL);
1136         }
1137
1138         /* decrease our supplies ref count and disable if required */
1139         if (rdev->supply)
1140                 _regulator_disable(rdev->supply);
1141
1142         rdev->use_count = 0;
1143         return ret;
1144 }
1145
1146 /**
1147  * regulator_force_disable - force disable regulator output
1148  * @regulator: regulator source
1149  *
1150  * Forcibly disable the regulator output voltage or current.
1151  * NOTE: this *will* disable the regulator output even if other consumer
1152  * devices have it enabled. This should be used for situations when device
1153  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1154  */
1155 int regulator_force_disable(struct regulator *regulator)
1156 {
1157         int ret;
1158
1159         mutex_lock(&regulator->rdev->mutex);
1160         regulator->enabled = 0;
1161         regulator->uA_load = 0;
1162         ret = _regulator_force_disable(regulator->rdev);
1163         mutex_unlock(&regulator->rdev->mutex);
1164         return ret;
1165 }
1166 EXPORT_SYMBOL_GPL(regulator_force_disable);
1167
1168 static int _regulator_is_enabled(struct regulator_dev *rdev)
1169 {
1170         int ret;
1171
1172         mutex_lock(&rdev->mutex);
1173
1174         /* sanity check */
1175         if (!rdev->desc->ops->is_enabled) {
1176                 ret = -EINVAL;
1177                 goto out;
1178         }
1179
1180         ret = rdev->desc->ops->is_enabled(rdev);
1181 out:
1182         mutex_unlock(&rdev->mutex);
1183         return ret;
1184 }
1185
1186 /**
1187  * regulator_is_enabled - is the regulator output enabled
1188  * @regulator: regulator source
1189  *
1190  * Returns positive if the regulator driver backing the source/client
1191  * has requested that the device be enabled, zero if it hasn't, else a
1192  * negative errno code.
1193  *
1194  * Note that the device backing this regulator handle can have multiple
1195  * users, so it might be enabled even if regulator_enable() was never
1196  * called for this particular source.
1197  */
1198 int regulator_is_enabled(struct regulator *regulator)
1199 {
1200         return _regulator_is_enabled(regulator->rdev);
1201 }
1202 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1203
1204 /**
1205  * regulator_set_voltage - set regulator output voltage
1206  * @regulator: regulator source
1207  * @min_uV: Minimum required voltage in uV
1208  * @max_uV: Maximum acceptable voltage in uV
1209  *
1210  * Sets a voltage regulator to the desired output voltage. This can be set
1211  * during any regulator state. IOW, regulator can be disabled or enabled.
1212  *
1213  * If the regulator is enabled then the voltage will change to the new value
1214  * immediately otherwise if the regulator is disabled the regulator will
1215  * output at the new voltage when enabled.
1216  *
1217  * NOTE: If the regulator is shared between several devices then the lowest
1218  * request voltage that meets the system constraints will be used.
1219  * NOTE: Regulator system constraints must be set for this regulator before
1220  * calling this function otherwise this call will fail.
1221  */
1222 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1223 {
1224         struct regulator_dev *rdev = regulator->rdev;
1225         int ret;
1226
1227         mutex_lock(&rdev->mutex);
1228
1229         /* sanity check */
1230         if (!rdev->desc->ops->set_voltage) {
1231                 ret = -EINVAL;
1232                 goto out;
1233         }
1234
1235         /* constraints check */
1236         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1237         if (ret < 0)
1238                 goto out;
1239         regulator->min_uV = min_uV;
1240         regulator->max_uV = max_uV;
1241         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1242
1243 out:
1244         mutex_unlock(&rdev->mutex);
1245         return ret;
1246 }
1247 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1248
1249 static int _regulator_get_voltage(struct regulator_dev *rdev)
1250 {
1251         /* sanity check */
1252         if (rdev->desc->ops->get_voltage)
1253                 return rdev->desc->ops->get_voltage(rdev);
1254         else
1255                 return -EINVAL;
1256 }
1257
1258 /**
1259  * regulator_get_voltage - get regulator output voltage
1260  * @regulator: regulator source
1261  *
1262  * This returns the current regulator voltage in uV.
1263  *
1264  * NOTE: If the regulator is disabled it will return the voltage value. This
1265  * function should not be used to determine regulator state.
1266  */
1267 int regulator_get_voltage(struct regulator *regulator)
1268 {
1269         int ret;
1270
1271         mutex_lock(&regulator->rdev->mutex);
1272
1273         ret = _regulator_get_voltage(regulator->rdev);
1274
1275         mutex_unlock(&regulator->rdev->mutex);
1276
1277         return ret;
1278 }
1279 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1280
1281 /**
1282  * regulator_set_current_limit - set regulator output current limit
1283  * @regulator: regulator source
1284  * @min_uA: Minimuum supported current in uA
1285  * @max_uA: Maximum supported current in uA
1286  *
1287  * Sets current sink to the desired output current. This can be set during
1288  * any regulator state. IOW, regulator can be disabled or enabled.
1289  *
1290  * If the regulator is enabled then the current will change to the new value
1291  * immediately otherwise if the regulator is disabled the regulator will
1292  * output at the new current when enabled.
1293  *
1294  * NOTE: Regulator system constraints must be set for this regulator before
1295  * calling this function otherwise this call will fail.
1296  */
1297 int regulator_set_current_limit(struct regulator *regulator,
1298                                int min_uA, int max_uA)
1299 {
1300         struct regulator_dev *rdev = regulator->rdev;
1301         int ret;
1302
1303         mutex_lock(&rdev->mutex);
1304
1305         /* sanity check */
1306         if (!rdev->desc->ops->set_current_limit) {
1307                 ret = -EINVAL;
1308                 goto out;
1309         }
1310
1311         /* constraints check */
1312         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1313         if (ret < 0)
1314                 goto out;
1315
1316         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1317 out:
1318         mutex_unlock(&rdev->mutex);
1319         return ret;
1320 }
1321 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1322
1323 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1324 {
1325         int ret;
1326
1327         mutex_lock(&rdev->mutex);
1328
1329         /* sanity check */
1330         if (!rdev->desc->ops->get_current_limit) {
1331                 ret = -EINVAL;
1332                 goto out;
1333         }
1334
1335         ret = rdev->desc->ops->get_current_limit(rdev);
1336 out:
1337         mutex_unlock(&rdev->mutex);
1338         return ret;
1339 }
1340
1341 /**
1342  * regulator_get_current_limit - get regulator output current
1343  * @regulator: regulator source
1344  *
1345  * This returns the current supplied by the specified current sink in uA.
1346  *
1347  * NOTE: If the regulator is disabled it will return the current value. This
1348  * function should not be used to determine regulator state.
1349  */
1350 int regulator_get_current_limit(struct regulator *regulator)
1351 {
1352         return _regulator_get_current_limit(regulator->rdev);
1353 }
1354 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1355
1356 /**
1357  * regulator_set_mode - set regulator operating mode
1358  * @regulator: regulator source
1359  * @mode: operating mode - one of the REGULATOR_MODE constants
1360  *
1361  * Set regulator operating mode to increase regulator efficiency or improve
1362  * regulation performance.
1363  *
1364  * NOTE: Regulator system constraints must be set for this regulator before
1365  * calling this function otherwise this call will fail.
1366  */
1367 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1368 {
1369         struct regulator_dev *rdev = regulator->rdev;
1370         int ret;
1371
1372         mutex_lock(&rdev->mutex);
1373
1374         /* sanity check */
1375         if (!rdev->desc->ops->set_mode) {
1376                 ret = -EINVAL;
1377                 goto out;
1378         }
1379
1380         /* constraints check */
1381         ret = regulator_check_mode(rdev, mode);
1382         if (ret < 0)
1383                 goto out;
1384
1385         ret = rdev->desc->ops->set_mode(rdev, mode);
1386 out:
1387         mutex_unlock(&rdev->mutex);
1388         return ret;
1389 }
1390 EXPORT_SYMBOL_GPL(regulator_set_mode);
1391
1392 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1393 {
1394         int ret;
1395
1396         mutex_lock(&rdev->mutex);
1397
1398         /* sanity check */
1399         if (!rdev->desc->ops->get_mode) {
1400                 ret = -EINVAL;
1401                 goto out;
1402         }
1403
1404         ret = rdev->desc->ops->get_mode(rdev);
1405 out:
1406         mutex_unlock(&rdev->mutex);
1407         return ret;
1408 }
1409
1410 /**
1411  * regulator_get_mode - get regulator operating mode
1412  * @regulator: regulator source
1413  *
1414  * Get the current regulator operating mode.
1415  */
1416 unsigned int regulator_get_mode(struct regulator *regulator)
1417 {
1418         return _regulator_get_mode(regulator->rdev);
1419 }
1420 EXPORT_SYMBOL_GPL(regulator_get_mode);
1421
1422 /**
1423  * regulator_set_optimum_mode - set regulator optimum operating mode
1424  * @regulator: regulator source
1425  * @uA_load: load current
1426  *
1427  * Notifies the regulator core of a new device load. This is then used by
1428  * DRMS (if enabled by constraints) to set the most efficient regulator
1429  * operating mode for the new regulator loading.
1430  *
1431  * Consumer devices notify their supply regulator of the maximum power
1432  * they will require (can be taken from device datasheet in the power
1433  * consumption tables) when they change operational status and hence power
1434  * state. Examples of operational state changes that can affect power
1435  * consumption are :-
1436  *
1437  *    o Device is opened / closed.
1438  *    o Device I/O is about to begin or has just finished.
1439  *    o Device is idling in between work.
1440  *
1441  * This information is also exported via sysfs to userspace.
1442  *
1443  * DRMS will sum the total requested load on the regulator and change
1444  * to the most efficient operating mode if platform constraints allow.
1445  *
1446  * Returns the new regulator mode or error.
1447  */
1448 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1449 {
1450         struct regulator_dev *rdev = regulator->rdev;
1451         struct regulator *consumer;
1452         int ret, output_uV, input_uV, total_uA_load = 0;
1453         unsigned int mode;
1454
1455         mutex_lock(&rdev->mutex);
1456
1457         regulator->uA_load = uA_load;
1458         ret = regulator_check_drms(rdev);
1459         if (ret < 0)
1460                 goto out;
1461         ret = -EINVAL;
1462
1463         /* sanity check */
1464         if (!rdev->desc->ops->get_optimum_mode)
1465                 goto out;
1466
1467         /* get output voltage */
1468         output_uV = rdev->desc->ops->get_voltage(rdev);
1469         if (output_uV <= 0) {
1470                 printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1471                         __func__, rdev->desc->name);
1472                 goto out;
1473         }
1474
1475         /* get input voltage */
1476         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1477                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1478         else
1479                 input_uV = rdev->constraints->input_uV;
1480         if (input_uV <= 0) {
1481                 printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1482                         __func__, rdev->desc->name);
1483                 goto out;
1484         }
1485
1486         /* calc total requested load for this regulator */
1487         list_for_each_entry(consumer, &rdev->consumer_list, list)
1488             total_uA_load += consumer->uA_load;
1489
1490         mode = rdev->desc->ops->get_optimum_mode(rdev,
1491                                                  input_uV, output_uV,
1492                                                  total_uA_load);
1493         ret = regulator_check_mode(rdev, mode);
1494         if (ret < 0) {
1495                 printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1496                         " %d uA %d -> %d uV\n", __func__, rdev->desc->name,
1497                         total_uA_load, input_uV, output_uV);
1498                 goto out;
1499         }
1500
1501         ret = rdev->desc->ops->set_mode(rdev, mode);
1502         if (ret < 0) {
1503                 printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1504                         __func__, mode, rdev->desc->name);
1505                 goto out;
1506         }
1507         ret = mode;
1508 out:
1509         mutex_unlock(&rdev->mutex);
1510         return ret;
1511 }
1512 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1513
1514 /**
1515  * regulator_register_notifier - register regulator event notifier
1516  * @regulator: regulator source
1517  * @notifier_block: notifier block
1518  *
1519  * Register notifier block to receive regulator events.
1520  */
1521 int regulator_register_notifier(struct regulator *regulator,
1522                               struct notifier_block *nb)
1523 {
1524         return blocking_notifier_chain_register(&regulator->rdev->notifier,
1525                                                 nb);
1526 }
1527 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1528
1529 /**
1530  * regulator_unregister_notifier - unregister regulator event notifier
1531  * @regulator: regulator source
1532  * @notifier_block: notifier block
1533  *
1534  * Unregister regulator event notifier block.
1535  */
1536 int regulator_unregister_notifier(struct regulator *regulator,
1537                                 struct notifier_block *nb)
1538 {
1539         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1540                                                   nb);
1541 }
1542 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1543
1544 /* notify regulator consumers and downstream regulator consumers */
1545 static void _notifier_call_chain(struct regulator_dev *rdev,
1546                                   unsigned long event, void *data)
1547 {
1548         struct regulator_dev *_rdev;
1549
1550         /* call rdev chain first */
1551         mutex_lock(&rdev->mutex);
1552         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1553         mutex_unlock(&rdev->mutex);
1554
1555         /* now notify regulator we supply */
1556         list_for_each_entry(_rdev, &rdev->supply_list, slist)
1557                 _notifier_call_chain(_rdev, event, data);
1558 }
1559
1560 /**
1561  * regulator_bulk_get - get multiple regulator consumers
1562  *
1563  * @dev:           Device to supply
1564  * @num_consumers: Number of consumers to register
1565  * @consumers:     Configuration of consumers; clients are stored here.
1566  *
1567  * @return 0 on success, an errno on failure.
1568  *
1569  * This helper function allows drivers to get several regulator
1570  * consumers in one operation.  If any of the regulators cannot be
1571  * acquired then any regulators that were allocated will be freed
1572  * before returning to the caller.
1573  */
1574 int regulator_bulk_get(struct device *dev, int num_consumers,
1575                        struct regulator_bulk_data *consumers)
1576 {
1577         int i;
1578         int ret;
1579
1580         for (i = 0; i < num_consumers; i++)
1581                 consumers[i].consumer = NULL;
1582
1583         for (i = 0; i < num_consumers; i++) {
1584                 consumers[i].consumer = regulator_get(dev,
1585                                                       consumers[i].supply);
1586                 if (IS_ERR(consumers[i].consumer)) {
1587                         dev_err(dev, "Failed to get supply '%s'\n",
1588                                 consumers[i].supply);
1589                         ret = PTR_ERR(consumers[i].consumer);
1590                         consumers[i].consumer = NULL;
1591                         goto err;
1592                 }
1593         }
1594
1595         return 0;
1596
1597 err:
1598         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1599                 regulator_put(consumers[i].consumer);
1600
1601         return ret;
1602 }
1603 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1604
1605 /**
1606  * regulator_bulk_enable - enable multiple regulator consumers
1607  *
1608  * @num_consumers: Number of consumers
1609  * @consumers:     Consumer data; clients are stored here.
1610  * @return         0 on success, an errno on failure
1611  *
1612  * This convenience API allows consumers to enable multiple regulator
1613  * clients in a single API call.  If any consumers cannot be enabled
1614  * then any others that were enabled will be disabled again prior to
1615  * return.
1616  */
1617 int regulator_bulk_enable(int num_consumers,
1618                           struct regulator_bulk_data *consumers)
1619 {
1620         int i;
1621         int ret;
1622
1623         for (i = 0; i < num_consumers; i++) {
1624                 ret = regulator_enable(consumers[i].consumer);
1625                 if (ret != 0)
1626                         goto err;
1627         }
1628
1629         return 0;
1630
1631 err:
1632         printk(KERN_ERR "Failed to enable %s\n", consumers[i].supply);
1633         for (i = 0; i < num_consumers; i++)
1634                 regulator_disable(consumers[i].consumer);
1635
1636         return ret;
1637 }
1638 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
1639
1640 /**
1641  * regulator_bulk_disable - disable multiple regulator consumers
1642  *
1643  * @num_consumers: Number of consumers
1644  * @consumers:     Consumer data; clients are stored here.
1645  * @return         0 on success, an errno on failure
1646  *
1647  * This convenience API allows consumers to disable multiple regulator
1648  * clients in a single API call.  If any consumers cannot be enabled
1649  * then any others that were disabled will be disabled again prior to
1650  * return.
1651  */
1652 int regulator_bulk_disable(int num_consumers,
1653                            struct regulator_bulk_data *consumers)
1654 {
1655         int i;
1656         int ret;
1657
1658         for (i = 0; i < num_consumers; i++) {
1659                 ret = regulator_disable(consumers[i].consumer);
1660                 if (ret != 0)
1661                         goto err;
1662         }
1663
1664         return 0;
1665
1666 err:
1667         printk(KERN_ERR "Failed to disable %s\n", consumers[i].supply);
1668         for (i = 0; i < num_consumers; i++)
1669                 regulator_enable(consumers[i].consumer);
1670
1671         return ret;
1672 }
1673 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
1674
1675 /**
1676  * regulator_bulk_free - free multiple regulator consumers
1677  *
1678  * @num_consumers: Number of consumers
1679  * @consumers:     Consumer data; clients are stored here.
1680  *
1681  * This convenience API allows consumers to free multiple regulator
1682  * clients in a single API call.
1683  */
1684 void regulator_bulk_free(int num_consumers,
1685                          struct regulator_bulk_data *consumers)
1686 {
1687         int i;
1688
1689         for (i = 0; i < num_consumers; i++) {
1690                 regulator_put(consumers[i].consumer);
1691                 consumers[i].consumer = NULL;
1692         }
1693 }
1694 EXPORT_SYMBOL_GPL(regulator_bulk_free);
1695
1696 /**
1697  * regulator_notifier_call_chain - call regulator event notifier
1698  * @regulator: regulator source
1699  * @event: notifier block
1700  * @data:
1701  *
1702  * Called by regulator drivers to notify clients a regulator event has
1703  * occurred. We also notify regulator clients downstream.
1704  */
1705 int regulator_notifier_call_chain(struct regulator_dev *rdev,
1706                                   unsigned long event, void *data)
1707 {
1708         _notifier_call_chain(rdev, event, data);
1709         return NOTIFY_DONE;
1710
1711 }
1712 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
1713
1714 /**
1715  * regulator_register - register regulator
1716  * @regulator: regulator source
1717  * @reg_data: private regulator data
1718  *
1719  * Called by regulator drivers to register a regulator.
1720  * Returns 0 on success.
1721  */
1722 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
1723         struct device *dev, void *driver_data)
1724 {
1725         static atomic_t regulator_no = ATOMIC_INIT(0);
1726         struct regulator_dev *rdev;
1727         struct regulator_init_data *init_data = dev->platform_data;
1728         int ret, i;
1729
1730         if (regulator_desc == NULL)
1731                 return ERR_PTR(-EINVAL);
1732
1733         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
1734                 return ERR_PTR(-EINVAL);
1735
1736         if (!regulator_desc->type == REGULATOR_VOLTAGE &&
1737             !regulator_desc->type == REGULATOR_CURRENT)
1738                 return ERR_PTR(-EINVAL);
1739
1740         if (!init_data)
1741                 return ERR_PTR(-EINVAL);
1742
1743         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
1744         if (rdev == NULL)
1745                 return ERR_PTR(-ENOMEM);
1746
1747         mutex_lock(&regulator_list_mutex);
1748
1749         mutex_init(&rdev->mutex);
1750         rdev->reg_data = driver_data;
1751         rdev->owner = regulator_desc->owner;
1752         rdev->desc = regulator_desc;
1753         INIT_LIST_HEAD(&rdev->consumer_list);
1754         INIT_LIST_HEAD(&rdev->supply_list);
1755         INIT_LIST_HEAD(&rdev->list);
1756         INIT_LIST_HEAD(&rdev->slist);
1757         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
1758
1759         /* preform any regulator specific init */
1760         if (init_data->regulator_init) {
1761                 ret = init_data->regulator_init(rdev->reg_data);
1762                 if (ret < 0)
1763                         goto clean;
1764         }
1765
1766         /* set regulator constraints */
1767         ret = set_machine_constraints(rdev, &init_data->constraints);
1768         if (ret < 0)
1769                 goto clean;
1770
1771         /* register with sysfs */
1772         rdev->dev.class = &regulator_class;
1773         rdev->dev.parent = dev;
1774         dev_set_name(&rdev->dev, "regulator.%d",
1775                      atomic_inc_return(&regulator_no) - 1);
1776         ret = device_register(&rdev->dev);
1777         if (ret != 0)
1778                 goto clean;
1779
1780         dev_set_drvdata(&rdev->dev, rdev);
1781
1782         /* set supply regulator if it exists */
1783         if (init_data->supply_regulator_dev) {
1784                 ret = set_supply(rdev,
1785                         dev_get_drvdata(init_data->supply_regulator_dev));
1786                 if (ret < 0)
1787                         goto scrub;
1788         }
1789
1790         /* add consumers devices */
1791         for (i = 0; i < init_data->num_consumer_supplies; i++) {
1792                 ret = set_consumer_device_supply(rdev,
1793                         init_data->consumer_supplies[i].dev,
1794                         init_data->consumer_supplies[i].supply);
1795                 if (ret < 0) {
1796                         for (--i; i >= 0; i--)
1797                                 unset_consumer_device_supply(rdev,
1798                                         init_data->consumer_supplies[i].dev);
1799                         goto scrub;
1800                 }
1801         }
1802
1803         list_add(&rdev->list, &regulator_list);
1804 out:
1805         mutex_unlock(&regulator_list_mutex);
1806         return rdev;
1807
1808 scrub:
1809         device_unregister(&rdev->dev);
1810 clean:
1811         kfree(rdev);
1812         rdev = ERR_PTR(ret);
1813         goto out;
1814 }
1815 EXPORT_SYMBOL_GPL(regulator_register);
1816
1817 /**
1818  * regulator_unregister - unregister regulator
1819  * @regulator: regulator source
1820  *
1821  * Called by regulator drivers to unregister a regulator.
1822  */
1823 void regulator_unregister(struct regulator_dev *rdev)
1824 {
1825         if (rdev == NULL)
1826                 return;
1827
1828         mutex_lock(&regulator_list_mutex);
1829         list_del(&rdev->list);
1830         if (rdev->supply)
1831                 sysfs_remove_link(&rdev->dev.kobj, "supply");
1832         device_unregister(&rdev->dev);
1833         mutex_unlock(&regulator_list_mutex);
1834 }
1835 EXPORT_SYMBOL_GPL(regulator_unregister);
1836
1837 /**
1838  * regulator_suspend_prepare: prepare regulators for system wide suspend
1839  * @state: system suspend state
1840  *
1841  * Configure each regulator with it's suspend operating parameters for state.
1842  * This will usually be called by machine suspend code prior to supending.
1843  */
1844 int regulator_suspend_prepare(suspend_state_t state)
1845 {
1846         struct regulator_dev *rdev;
1847         int ret = 0;
1848
1849         /* ON is handled by regulator active state */
1850         if (state == PM_SUSPEND_ON)
1851                 return -EINVAL;
1852
1853         mutex_lock(&regulator_list_mutex);
1854         list_for_each_entry(rdev, &regulator_list, list) {
1855
1856                 mutex_lock(&rdev->mutex);
1857                 ret = suspend_prepare(rdev, state);
1858                 mutex_unlock(&rdev->mutex);
1859
1860                 if (ret < 0) {
1861                         printk(KERN_ERR "%s: failed to prepare %s\n",
1862                                 __func__, rdev->desc->name);
1863                         goto out;
1864                 }
1865         }
1866 out:
1867         mutex_unlock(&regulator_list_mutex);
1868         return ret;
1869 }
1870 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
1871
1872 /**
1873  * rdev_get_drvdata - get rdev regulator driver data
1874  * @regulator: regulator
1875  *
1876  * Get rdev regulator driver private data. This call can be used in the
1877  * regulator driver context.
1878  */
1879 void *rdev_get_drvdata(struct regulator_dev *rdev)
1880 {
1881         return rdev->reg_data;
1882 }
1883 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
1884
1885 /**
1886  * regulator_get_drvdata - get regulator driver data
1887  * @regulator: regulator
1888  *
1889  * Get regulator driver private data. This call can be used in the consumer
1890  * driver context when non API regulator specific functions need to be called.
1891  */
1892 void *regulator_get_drvdata(struct regulator *regulator)
1893 {
1894         return regulator->rdev->reg_data;
1895 }
1896 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
1897
1898 /**
1899  * regulator_set_drvdata - set regulator driver data
1900  * @regulator: regulator
1901  * @data: data
1902  */
1903 void regulator_set_drvdata(struct regulator *regulator, void *data)
1904 {
1905         regulator->rdev->reg_data = data;
1906 }
1907 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
1908
1909 /**
1910  * regulator_get_id - get regulator ID
1911  * @regulator: regulator
1912  */
1913 int rdev_get_id(struct regulator_dev *rdev)
1914 {
1915         return rdev->desc->id;
1916 }
1917 EXPORT_SYMBOL_GPL(rdev_get_id);
1918
1919 struct device *rdev_get_dev(struct regulator_dev *rdev)
1920 {
1921         return &rdev->dev;
1922 }
1923 EXPORT_SYMBOL_GPL(rdev_get_dev);
1924
1925 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
1926 {
1927         return reg_init_data->driver_data;
1928 }
1929 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
1930
1931 static int __init regulator_init(void)
1932 {
1933         printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
1934         return class_register(&regulator_class);
1935 }
1936
1937 /* init early to allow our consumers to complete system booting */
1938 core_initcall(regulator_init);