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/slab.h>
  20 #include <linux/err.h>
  21 #include <linux/mutex.h>
  22 #include <linux/suspend.h>
  23 #include <linux/delay.h>
  24 #include <linux/regulator/consumer.h>
  25 #include <linux/regulator/driver.h>
  26 #include <linux/regulator/machine.h>
  27
  28 #include "dummy.h"
  29
  30 #define REGULATOR_VERSION "0.5"
  31
  32 static DEFINE_MUTEX(regulator_list_mutex);
  33 static LIST_HEAD(regulator_list);
  34 static LIST_HEAD(regulator_map_list);
  35 static int has_full_constraints;
  36
  37 /*
  38  * struct regulator_map
  39  *
  40  * Used to provide symbolic supply names to devices.
  41  */
  42 struct regulator_map {
  43         struct list_head list;
  44         const char *dev_name;   /* The dev_name() for the consumer */
  45         const char *supply;
  46         struct regulator_dev *regulator;
  47 };
  48
  49 /*
  50  * struct regulator
  51  *
  52  * One for each consumer device.
  53  */
  54 struct regulator {
  55         struct device *dev;
  56         struct list_head list;
  57         int uA_load;
  58         int min_uV;
  59         int max_uV;
  60         char *supply_name;
  61         struct device_attribute dev_attr;
  62         struct regulator_dev *rdev;
  63 };
  64
  65 static int _regulator_is_enabled(struct regulator_dev *rdev);
  66 static int _regulator_disable(struct regulator_dev *rdev);
  67 static int _regulator_get_voltage(struct regulator_dev *rdev);
  68 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  69 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  70 static void _notifier_call_chain(struct regulator_dev *rdev,
  71                                   unsigned long event, void *data);
  72
  73 static const char *rdev_get_name(struct regulator_dev *rdev)
  74 {
  75         if (rdev->constraints && rdev->constraints->name)
  76                 return rdev->constraints->name;
  77         else if (rdev->desc->name)
  78                 return rdev->desc->name;
  79         else
  80                 return "";
  81 }
  82
  83 /* gets the regulator for a given consumer device */
  84 static struct regulator *get_device_regulator(struct device *dev)
  85 {
  86         struct regulator *regulator = NULL;
  87         struct regulator_dev *rdev;
  88
  89         mutex_lock(&regulator_list_mutex);
  90         list_for_each_entry(rdev, &regulator_list, list) {
  91                 mutex_lock(&rdev->mutex);
  92                 list_for_each_entry(regulator, &rdev->consumer_list, list) {
  93                         if (regulator->dev == dev) {
  94                                 mutex_unlock(&rdev->mutex);
  95                                 mutex_unlock(&regulator_list_mutex);
  96                                 return regulator;
  97                         }
  98                 }
  99                 mutex_unlock(&rdev->mutex);
 100         }
 101         mutex_unlock(&regulator_list_mutex);
 102         return NULL;
 103 }
 104
 105 /* Platform voltage constraint check */
 106 static int regulator_check_voltage(struct regulator_dev *rdev,
 107                                    int *min_uV, int *max_uV)
 108 {
 109         BUG_ON(*min_uV > *max_uV);
 110
 111         if (!rdev->constraints) {
 112                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 113                        rdev_get_name(rdev));
 114                 return -ENODEV;
 115         }
 116         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE)) {
 117                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 118                        __func__, rdev_get_name(rdev));
 119                 return -EPERM;
 120         }
 121
 122         if (*max_uV > rdev->constraints->max_uV)
 123                 *max_uV = rdev->constraints->max_uV;
 124         if (*min_uV < rdev->constraints->min_uV)
 125                 *min_uV = rdev->constraints->min_uV;
 126
 127         if (*min_uV > *max_uV)
 128                 return -EINVAL;
 129
 130         return 0;
 131 }
 132
 133 /* current constraint check */
 134 static int regulator_check_current_limit(struct regulator_dev *rdev,
 135                                         int *min_uA, int *max_uA)
 136 {
 137         BUG_ON(*min_uA > *max_uA);
 138
 139         if (!rdev->constraints) {
 140                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 141                        rdev_get_name(rdev));
 142                 return -ENODEV;
 143         }
 144         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_CURRENT)) {
 145                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 146                        __func__, rdev_get_name(rdev));
 147                 return -EPERM;
 148         }
 149
 150         if (*max_uA > rdev->constraints->max_uA)
 151                 *max_uA = rdev->constraints->max_uA;
 152         if (*min_uA < rdev->constraints->min_uA)
 153                 *min_uA = rdev->constraints->min_uA;
 154
 155         if (*min_uA > *max_uA)
 156                 return -EINVAL;
 157
 158         return 0;
 159 }
 160
 161 /* operating mode constraint check */
 162 static int regulator_check_mode(struct regulator_dev *rdev, int mode)
 163 {
 164         switch (mode) {
 165         case REGULATOR_MODE_FAST:
 166         case REGULATOR_MODE_NORMAL:
 167         case REGULATOR_MODE_IDLE:
 168         case REGULATOR_MODE_STANDBY:
 169                 break;
 170         default:
 171                 return -EINVAL;
 172         }
 173
 174         if (!rdev->constraints) {
 175                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 176                        rdev_get_name(rdev));
 177                 return -ENODEV;
 178         }
 179         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_MODE)) {
 180                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 181                        __func__, rdev_get_name(rdev));
 182                 return -EPERM;
 183         }
 184         if (!(rdev->constraints->valid_modes_mask & mode)) {
 185                 printk(KERN_ERR "%s: invalid mode %x for %s\n",
 186                        __func__, mode, rdev_get_name(rdev));
 187                 return -EINVAL;
 188         }
 189         return 0;
 190 }
 191
 192 /* dynamic regulator mode switching constraint check */
 193 static int regulator_check_drms(struct regulator_dev *rdev)
 194 {
 195         if (!rdev->constraints) {
 196                 printk(KERN_ERR "%s: no constraints for %s\n", __func__,
 197                        rdev_get_name(rdev));
 198                 return -ENODEV;
 199         }
 200         if (!(rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) {
 201                 printk(KERN_ERR "%s: operation not allowed for %s\n",
 202                        __func__, rdev_get_name(rdev));
 203                 return -EPERM;
 204         }
 205         return 0;
 206 }
 207
 208 static ssize_t device_requested_uA_show(struct device *dev,
 209                              struct device_attribute *attr, char *buf)
 210 {
 211         struct regulator *regulator;
 212
 213         regulator = get_device_regulator(dev);
 214         if (regulator == NULL)
 215                 return 0;
 216
 217         return sprintf(buf, "%d\n", regulator->uA_load);
 218 }
 219
 220 static ssize_t regulator_uV_show(struct device *dev,
 221                                 struct device_attribute *attr, char *buf)
 222 {
 223         struct regulator_dev *rdev = dev_get_drvdata(dev);
 224         ssize_t ret;
 225
 226         mutex_lock(&rdev->mutex);
 227         ret = sprintf(buf, "%d\n", _regulator_get_voltage(rdev));
 228         mutex_unlock(&rdev->mutex);
 229
 230         return ret;
 231 }
 232 static DEVICE_ATTR(microvolts, 0444, regulator_uV_show, NULL);
 233
 234 static ssize_t regulator_uA_show(struct device *dev,
 235                                 struct device_attribute *attr, char *buf)
 236 {
 237         struct regulator_dev *rdev = dev_get_drvdata(dev);
 238
 239         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 240 }
 241 static DEVICE_ATTR(microamps, 0444, regulator_uA_show, NULL);
 242
 243 static ssize_t regulator_name_show(struct device *dev,
 244                              struct device_attribute *attr, char *buf)
 245 {
 246         struct regulator_dev *rdev = dev_get_drvdata(dev);
 247
 248         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 249 }
 250
 251 static ssize_t regulator_print_opmode(char *buf, int mode)
 252 {
 253         switch (mode) {
 254         case REGULATOR_MODE_FAST:
 255                 return sprintf(buf, "fast\n");
 256         case REGULATOR_MODE_NORMAL:
 257                 return sprintf(buf, "normal\n");
 258         case REGULATOR_MODE_IDLE:
 259                 return sprintf(buf, "idle\n");
 260         case REGULATOR_MODE_STANDBY:
 261                 return sprintf(buf, "standby\n");
 262         }
 263         return sprintf(buf, "unknown\n");
 264 }
 265
 266 static ssize_t regulator_opmode_show(struct device *dev,
 267                                     struct device_attribute *attr, char *buf)
 268 {
 269         struct regulator_dev *rdev = dev_get_drvdata(dev);
 270
 271         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 272 }
 273 static DEVICE_ATTR(opmode, 0444, regulator_opmode_show, NULL);
 274
 275 static ssize_t regulator_print_state(char *buf, int state)
 276 {
 277         if (state > 0)
 278                 return sprintf(buf, "enabled\n");
 279         else if (state == 0)
 280                 return sprintf(buf, "disabled\n");
 281         else
 282                 return sprintf(buf, "unknown\n");
 283 }
 284
 285 static ssize_t regulator_state_show(struct device *dev,
 286                                    struct device_attribute *attr, char *buf)
 287 {
 288         struct regulator_dev *rdev = dev_get_drvdata(dev);
 289         ssize_t ret;
 290
 291         mutex_lock(&rdev->mutex);
 292         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 293         mutex_unlock(&rdev->mutex);
 294
 295         return ret;
 296 }
 297 static DEVICE_ATTR(state, 0444, regulator_state_show, NULL);
 298
 299 static ssize_t regulator_status_show(struct device *dev,
 300                                    struct device_attribute *attr, char *buf)
 301 {
 302         struct regulator_dev *rdev = dev_get_drvdata(dev);
 303         int status;
 304         char *label;
 305
 306         status = rdev->desc->ops->get_status(rdev);
 307         if (status < 0)
 308                 return status;
 309
 310         switch (status) {
 311         case REGULATOR_STATUS_OFF:
 312                 label = "off";
 313                 break;
 314         case REGULATOR_STATUS_ON:
 315                 label = "on";
 316                 break;
 317         case REGULATOR_STATUS_ERROR:
 318                 label = "error";
 319                 break;
 320         case REGULATOR_STATUS_FAST:
 321                 label = "fast";
 322                 break;
 323         case REGULATOR_STATUS_NORMAL:
 324                 label = "normal";
 325                 break;
 326         case REGULATOR_STATUS_IDLE:
 327                 label = "idle";
 328                 break;
 329         case REGULATOR_STATUS_STANDBY:
 330                 label = "standby";
 331                 break;
 332         default:
 333                 return -ERANGE;
 334         }
 335
 336         return sprintf(buf, "%s\n", label);
 337 }
 338 static DEVICE_ATTR(status, 0444, regulator_status_show, NULL);
 339
 340 static ssize_t regulator_min_uA_show(struct device *dev,
 341                                     struct device_attribute *attr, char *buf)
 342 {
 343         struct regulator_dev *rdev = dev_get_drvdata(dev);
 344
 345         if (!rdev->constraints)
 346                 return sprintf(buf, "constraint not defined\n");
 347
 348         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 349 }
 350 static DEVICE_ATTR(min_microamps, 0444, regulator_min_uA_show, NULL);
 351
 352 static ssize_t regulator_max_uA_show(struct device *dev,
 353                                     struct device_attribute *attr, char *buf)
 354 {
 355         struct regulator_dev *rdev = dev_get_drvdata(dev);
 356
 357         if (!rdev->constraints)
 358                 return sprintf(buf, "constraint not defined\n");
 359
 360         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 361 }
 362 static DEVICE_ATTR(max_microamps, 0444, regulator_max_uA_show, NULL);
 363
 364 static ssize_t regulator_min_uV_show(struct device *dev,
 365                                     struct device_attribute *attr, char *buf)
 366 {
 367         struct regulator_dev *rdev = dev_get_drvdata(dev);
 368
 369         if (!rdev->constraints)
 370                 return sprintf(buf, "constraint not defined\n");
 371
 372         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 373 }
 374 static DEVICE_ATTR(min_microvolts, 0444, regulator_min_uV_show, NULL);
 375
 376 static ssize_t regulator_max_uV_show(struct device *dev,
 377                                     struct device_attribute *attr, char *buf)
 378 {
 379         struct regulator_dev *rdev = dev_get_drvdata(dev);
 380
 381         if (!rdev->constraints)
 382                 return sprintf(buf, "constraint not defined\n");
 383
 384         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 385 }
 386 static DEVICE_ATTR(max_microvolts, 0444, regulator_max_uV_show, NULL);
 387
 388 static ssize_t regulator_total_uA_show(struct device *dev,
 389                                       struct device_attribute *attr, char *buf)
 390 {
 391         struct regulator_dev *rdev = dev_get_drvdata(dev);
 392         struct regulator *regulator;
 393         int uA = 0;
 394
 395         mutex_lock(&rdev->mutex);
 396         list_for_each_entry(regulator, &rdev->consumer_list, list)
 397                 uA += regulator->uA_load;
 398         mutex_unlock(&rdev->mutex);
 399         return sprintf(buf, "%d\n", uA);
 400 }
 401 static DEVICE_ATTR(requested_microamps, 0444, regulator_total_uA_show, NULL);
 402
 403 static ssize_t regulator_num_users_show(struct device *dev,
 404                                       struct device_attribute *attr, char *buf)
 405 {
 406         struct regulator_dev *rdev = dev_get_drvdata(dev);
 407         return sprintf(buf, "%d\n", rdev->use_count);
 408 }
 409
 410 static ssize_t regulator_type_show(struct device *dev,
 411                                   struct device_attribute *attr, char *buf)
 412 {
 413         struct regulator_dev *rdev = dev_get_drvdata(dev);
 414
 415         switch (rdev->desc->type) {
 416         case REGULATOR_VOLTAGE:
 417                 return sprintf(buf, "voltage\n");
 418         case REGULATOR_CURRENT:
 419                 return sprintf(buf, "current\n");
 420         }
 421         return sprintf(buf, "unknown\n");
 422 }
 423
 424 static ssize_t regulator_suspend_mem_uV_show(struct device *dev,
 425                                 struct device_attribute *attr, char *buf)
 426 {
 427         struct regulator_dev *rdev = dev_get_drvdata(dev);
 428
 429         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 430 }
 431 static DEVICE_ATTR(suspend_mem_microvolts, 0444,
 432                 regulator_suspend_mem_uV_show, NULL);
 433
 434 static ssize_t regulator_suspend_disk_uV_show(struct device *dev,
 435                                 struct device_attribute *attr, char *buf)
 436 {
 437         struct regulator_dev *rdev = dev_get_drvdata(dev);
 438
 439         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 440 }
 441 static DEVICE_ATTR(suspend_disk_microvolts, 0444,
 442                 regulator_suspend_disk_uV_show, NULL);
 443
 444 static ssize_t regulator_suspend_standby_uV_show(struct device *dev,
 445                                 struct device_attribute *attr, char *buf)
 446 {
 447         struct regulator_dev *rdev = dev_get_drvdata(dev);
 448
 449         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 450 }
 451 static DEVICE_ATTR(suspend_standby_microvolts, 0444,
 452                 regulator_suspend_standby_uV_show, NULL);
 453
 454 static ssize_t regulator_suspend_mem_mode_show(struct device *dev,
 455                                 struct device_attribute *attr, char *buf)
 456 {
 457         struct regulator_dev *rdev = dev_get_drvdata(dev);
 458
 459         return regulator_print_opmode(buf,
 460                 rdev->constraints->state_mem.mode);
 461 }
 462 static DEVICE_ATTR(suspend_mem_mode, 0444,
 463                 regulator_suspend_mem_mode_show, NULL);
 464
 465 static ssize_t regulator_suspend_disk_mode_show(struct device *dev,
 466                                 struct device_attribute *attr, char *buf)
 467 {
 468         struct regulator_dev *rdev = dev_get_drvdata(dev);
 469
 470         return regulator_print_opmode(buf,
 471                 rdev->constraints->state_disk.mode);
 472 }
 473 static DEVICE_ATTR(suspend_disk_mode, 0444,
 474                 regulator_suspend_disk_mode_show, NULL);
 475
 476 static ssize_t regulator_suspend_standby_mode_show(struct device *dev,
 477                                 struct device_attribute *attr, char *buf)
 478 {
 479         struct regulator_dev *rdev = dev_get_drvdata(dev);
 480
 481         return regulator_print_opmode(buf,
 482                 rdev->constraints->state_standby.mode);
 483 }
 484 static DEVICE_ATTR(suspend_standby_mode, 0444,
 485                 regulator_suspend_standby_mode_show, NULL);
 486
 487 static ssize_t regulator_suspend_mem_state_show(struct device *dev,
 488                                    struct device_attribute *attr, char *buf)
 489 {
 490         struct regulator_dev *rdev = dev_get_drvdata(dev);
 491
 492         return regulator_print_state(buf,
 493                         rdev->constraints->state_mem.enabled);
 494 }
 495 static DEVICE_ATTR(suspend_mem_state, 0444,
 496                 regulator_suspend_mem_state_show, NULL);
 497
 498 static ssize_t regulator_suspend_disk_state_show(struct device *dev,
 499                                    struct device_attribute *attr, char *buf)
 500 {
 501         struct regulator_dev *rdev = dev_get_drvdata(dev);
 502
 503         return regulator_print_state(buf,
 504                         rdev->constraints->state_disk.enabled);
 505 }
 506 static DEVICE_ATTR(suspend_disk_state, 0444,
 507                 regulator_suspend_disk_state_show, NULL);
 508
 509 static ssize_t regulator_suspend_standby_state_show(struct device *dev,
 510                                    struct device_attribute *attr, char *buf)
 511 {
 512         struct regulator_dev *rdev = dev_get_drvdata(dev);
 513
 514         return regulator_print_state(buf,
 515                         rdev->constraints->state_standby.enabled);
 516 }
 517 static DEVICE_ATTR(suspend_standby_state, 0444,
 518                 regulator_suspend_standby_state_show, NULL);
 519
 520
 521 /*
 522  * These are the only attributes are present for all regulators.
 523  * Other attributes are a function of regulator functionality.
 524  */
 525 static struct device_attribute regulator_dev_attrs[] = {
 526         __ATTR(name, 0444, regulator_name_show, NULL),
 527         __ATTR(num_users, 0444, regulator_num_users_show, NULL),
 528         __ATTR(type, 0444, regulator_type_show, NULL),
 529         __ATTR_NULL,
 530 };
 531
 532 static void regulator_dev_release(struct device *dev)
 533 {
 534         struct regulator_dev *rdev = dev_get_drvdata(dev);
 535         kfree(rdev);
 536 }
 537
 538 static struct class regulator_class = {
 539         .name = "regulator",
 540         .dev_release = regulator_dev_release,
 541         .dev_attrs = regulator_dev_attrs,
 542 };
 543
 544 /* Calculate the new optimum regulator operating mode based on the new total
 545  * consumer load. All locks held by caller */
 546 static void drms_uA_update(struct regulator_dev *rdev)
 547 {
 548         struct regulator *sibling;
 549         int current_uA = 0, output_uV, input_uV, err;
 550         unsigned int mode;
 551
 552         err = regulator_check_drms(rdev);
 553         if (err < 0 || !rdev->desc->ops->get_optimum_mode ||
 554             !rdev->desc->ops->get_voltage || !rdev->desc->ops->set_mode)
 555                 return;
 556
 557         /* get output voltage */
 558         output_uV = rdev->desc->ops->get_voltage(rdev);
 559         if (output_uV <= 0)
 560                 return;
 561
 562         /* get input voltage */
 563         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
 564                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
 565         else
 566                 input_uV = rdev->constraints->input_uV;
 567         if (input_uV <= 0)
 568                 return;
 569
 570         /* calc total requested load */
 571         list_for_each_entry(sibling, &rdev->consumer_list, list)
 572                 current_uA += sibling->uA_load;
 573
 574         /* now get the optimum mode for our new total regulator load */
 575         mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
 576                                                   output_uV, current_uA);
 577
 578         /* check the new mode is allowed */
 579         err = regulator_check_mode(rdev, mode);
 580         if (err == 0)
 581                 rdev->desc->ops->set_mode(rdev, mode);
 582 }
 583
 584 static int suspend_set_state(struct regulator_dev *rdev,
 585         struct regulator_state *rstate)
 586 {
 587         int ret = 0;
 588         bool can_set_state;
 589
 590         can_set_state = rdev->desc->ops->set_suspend_enable &&
 591                 rdev->desc->ops->set_suspend_disable;
 592
 593         /* If we have no suspend mode configration don't set anything;
 594          * only warn if the driver actually makes the suspend mode
 595          * configurable.
 596          */
 597         if (!rstate->enabled && !rstate->disabled) {
 598                 if (can_set_state)
 599                         printk(KERN_WARNING "%s: No configuration for %s\n",
 600                                __func__, rdev_get_name(rdev));
 601                 return 0;
 602         }
 603
 604         if (rstate->enabled && rstate->disabled) {
 605                 printk(KERN_ERR "%s: invalid configuration for %s\n",
 606                        __func__, rdev_get_name(rdev));
 607                 return -EINVAL;
 608         }
 609
 610         if (!can_set_state) {
 611                 printk(KERN_ERR "%s: no way to set suspend state\n",
 612                         __func__);
 613                 return -EINVAL;
 614         }
 615
 616         if (rstate->enabled)
 617                 ret = rdev->desc->ops->set_suspend_enable(rdev);
 618         else
 619                 ret = rdev->desc->ops->set_suspend_disable(rdev);
 620         if (ret < 0) {
 621                 printk(KERN_ERR "%s: failed to enabled/disable\n", __func__);
 622                 return ret;
 623         }
 624
 625         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
 626                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
 627                 if (ret < 0) {
 628                         printk(KERN_ERR "%s: failed to set voltage\n",
 629                                 __func__);
 630                         return ret;
 631                 }
 632         }
 633
 634         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
 635                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
 636                 if (ret < 0) {
 637                         printk(KERN_ERR "%s: failed to set mode\n", __func__);
 638                         return ret;
 639                 }
 640         }
 641         return ret;
 642 }
 643
 644 /* locks held by caller */
 645 static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state)
 646 {
 647         if (!rdev->constraints)
 648                 return -EINVAL;
 649
 650         switch (state) {
 651         case PM_SUSPEND_STANDBY:
 652                 return suspend_set_state(rdev,
 653                         &rdev->constraints->state_standby);
 654         case PM_SUSPEND_MEM:
 655                 return suspend_set_state(rdev,
 656                         &rdev->constraints->state_mem);
 657         case PM_SUSPEND_MAX:
 658                 return suspend_set_state(rdev,
 659                         &rdev->constraints->state_disk);
 660         default:
 661                 return -EINVAL;
 662         }
 663 }
 664
 665 static void print_constraints(struct regulator_dev *rdev)
 666 {
 667         struct regulation_constraints *constraints = rdev->constraints;
 668         char buf[80] = "";
 669         int count = 0;
 670         int ret;
 671
 672         if (constraints->min_uV && constraints->max_uV) {
 673                 if (constraints->min_uV == constraints->max_uV)
 674                         count += sprintf(buf + count, "%d mV ",
 675                                          constraints->min_uV / 1000);
 676                 else
 677                         count += sprintf(buf + count, "%d <--> %d mV ",
 678                                          constraints->min_uV / 1000,
 679                                          constraints->max_uV / 1000);
 680         }
 681
 682         if (!constraints->min_uV ||
 683             constraints->min_uV != constraints->max_uV) {
 684                 ret = _regulator_get_voltage(rdev);
 685                 if (ret > 0)
 686                         count += sprintf(buf + count, "at %d mV ", ret / 1000);
 687         }
 688
 689         if (constraints->min_uA && constraints->max_uA) {
 690                 if (constraints->min_uA == constraints->max_uA)
 691                         count += sprintf(buf + count, "%d mA ",
 692                                          constraints->min_uA / 1000);
 693                 else
 694                         count += sprintf(buf + count, "%d <--> %d mA ",
 695                                          constraints->min_uA / 1000,
 696                                          constraints->max_uA / 1000);
 697         }
 698
 699         if (!constraints->min_uA ||
 700             constraints->min_uA != constraints->max_uA) {
 701                 ret = _regulator_get_current_limit(rdev);
 702                 if (ret > 0)
 703                         count += sprintf(buf + count, "at %d uA ", ret / 1000);
 704         }
 705
 706         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
 707                 count += sprintf(buf + count, "fast ");
 708         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
 709                 count += sprintf(buf + count, "normal ");
 710         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
 711                 count += sprintf(buf + count, "idle ");
 712         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
 713                 count += sprintf(buf + count, "standby");
 714
 715         printk(KERN_INFO "regulator: %s: %s\n", rdev_get_name(rdev), buf);
 716 }
 717
 718 static int machine_constraints_voltage(struct regulator_dev *rdev,
 719         struct regulation_constraints *constraints)
 720 {
 721         struct regulator_ops *ops = rdev->desc->ops;
 722         const char *name = rdev_get_name(rdev);
 723         int ret;
 724
 725         /* do we need to apply the constraint voltage */
 726         if (rdev->constraints->apply_uV &&
 727                 rdev->constraints->min_uV == rdev->constraints->max_uV &&
 728                 ops->set_voltage) {
 729                 ret = ops->set_voltage(rdev,
 730                         rdev->constraints->min_uV, rdev->constraints->max_uV);
 731                         if (ret < 0) {
 732                                 printk(KERN_ERR "%s: failed to apply %duV constraint to %s\n",
 733                                        __func__,
 734                                        rdev->constraints->min_uV, name);
 735                                 rdev->constraints = NULL;
 736                                 return ret;
 737                         }
 738         }
 739
 740         /* constrain machine-level voltage specs to fit
 741          * the actual range supported by this regulator.
 742          */
 743         if (ops->list_voltage && rdev->desc->n_voltages) {
 744                 int     count = rdev->desc->n_voltages;
 745                 int     i;
 746                 int     min_uV = INT_MAX;
 747                 int     max_uV = INT_MIN;
 748                 int     cmin = constraints->min_uV;
 749                 int     cmax = constraints->max_uV;
 750
 751                 /* it's safe to autoconfigure fixed-voltage supplies
 752                    and the constraints are used by list_voltage. */
 753                 if (count == 1 && !cmin) {
 754                         cmin = 1;
 755                         cmax = INT_MAX;
 756                         constraints->min_uV = cmin;
 757                         constraints->max_uV = cmax;
 758                 }
 759
 760                 /* voltage constraints are optional */
 761                 if ((cmin == 0) && (cmax == 0))
 762                         return 0;
 763
 764                 /* else require explicit machine-level constraints */
 765                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
 766                         pr_err("%s: %s '%s' voltage constraints\n",
 767                                        __func__, "invalid", name);
 768                         return -EINVAL;
 769                 }
 770
 771                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
 772                 for (i = 0; i < count; i++) {
 773                         int     value;
 774
 775                         value = ops->list_voltage(rdev, i);
 776                         if (value <= 0)
 777                                 continue;
 778
 779                         /* maybe adjust [min_uV..max_uV] */
 780                         if (value >= cmin && value < min_uV)
 781                                 min_uV = value;
 782                         if (value <= cmax && value > max_uV)
 783                                 max_uV = value;
 784                 }
 785
 786                 /* final: [min_uV..max_uV] valid iff constraints valid */
 787                 if (max_uV < min_uV) {
 788                         pr_err("%s: %s '%s' voltage constraints\n",
 789                                        __func__, "unsupportable", name);
 790                         return -EINVAL;
 791                 }
 792
 793                 /* use regulator's subset of machine constraints */
 794                 if (constraints->min_uV < min_uV) {
 795                         pr_debug("%s: override '%s' %s, %d -> %d\n",
 796                                        __func__, name, "min_uV",
 797                                         constraints->min_uV, min_uV);
 798                         constraints->min_uV = min_uV;
 799                 }
 800                 if (constraints->max_uV > max_uV) {
 801                         pr_debug("%s: override '%s' %s, %d -> %d\n",
 802                                        __func__, name, "max_uV",
 803                                         constraints->max_uV, max_uV);
 804                         constraints->max_uV = max_uV;
 805                 }
 806         }
 807
 808         return 0;
 809 }
 810
 811 /**
 812  * set_machine_constraints - sets regulator constraints
 813  * @rdev: regulator source
 814  * @constraints: constraints to apply
 815  *
 816  * Allows platform initialisation code to define and constrain
 817  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
 818  * Constraints *must* be set by platform code in order for some
 819  * regulator operations to proceed i.e. set_voltage, set_current_limit,
 820  * set_mode.
 821  */
 822 static int set_machine_constraints(struct regulator_dev *rdev,
 823         struct regulation_constraints *constraints)
 824 {
 825         int ret = 0;
 826         const char *name;
 827         struct regulator_ops *ops = rdev->desc->ops;
 828
 829         rdev->constraints = constraints;
 830
 831         name = rdev_get_name(rdev);
 832
 833         ret = machine_constraints_voltage(rdev, constraints);
 834         if (ret != 0)
 835                 goto out;
 836
 837         /* do we need to setup our suspend state */
 838         if (constraints->initial_state) {
 839                 ret = suspend_prepare(rdev, constraints->initial_state);
 840                 if (ret < 0) {
 841                         printk(KERN_ERR "%s: failed to set suspend state for %s\n",
 842                                __func__, name);
 843                         rdev->constraints = NULL;
 844                         goto out;
 845                 }
 846         }
 847
 848         if (constraints->initial_mode) {
 849                 if (!ops->set_mode) {
 850                         printk(KERN_ERR "%s: no set_mode operation for %s\n",
 851                                __func__, name);
 852                         ret = -EINVAL;
 853                         goto out;
 854                 }
 855
 856                 ret = ops->set_mode(rdev, constraints->initial_mode);
 857                 if (ret < 0) {
 858                         printk(KERN_ERR
 859                                "%s: failed to set initial mode for %s: %d\n",
 860                                __func__, name, ret);
 861                         goto out;
 862                 }
 863         }
 864
 865         /* If the constraints say the regulator should be on at this point
 866          * and we have control then make sure it is enabled.
 867          */
 868         if ((constraints->always_on || constraints->boot_on) && ops->enable) {
 869                 ret = ops->enable(rdev);
 870                 if (ret < 0) {
 871                         printk(KERN_ERR "%s: failed to enable %s\n",
 872                                __func__, name);
 873                         rdev->constraints = NULL;
 874                         goto out;
 875                 }
 876         }
 877
 878         print_constraints(rdev);
 879 out:
 880         return ret;
 881 }
 882
 883 /**
 884  * set_supply - set regulator supply regulator
 885  * @rdev: regulator name
 886  * @supply_rdev: supply regulator name
 887  *
 888  * Called by platform initialisation code to set the supply regulator for this
 889  * regulator. This ensures that a regulators supply will also be enabled by the
 890  * core if it's child is enabled.
 891  */
 892 static int set_supply(struct regulator_dev *rdev,
 893         struct regulator_dev *supply_rdev)
 894 {
 895         int err;
 896
 897         err = sysfs_create_link(&rdev->dev.kobj, &supply_rdev->dev.kobj,
 898                                 "supply");
 899         if (err) {
 900                 printk(KERN_ERR
 901                        "%s: could not add device link %s err %d\n",
 902                        __func__, supply_rdev->dev.kobj.name, err);
 903                        goto out;
 904         }
 905         rdev->supply = supply_rdev;
 906         list_add(&rdev->slist, &supply_rdev->supply_list);
 907 out:
 908         return err;
 909 }
 910
 911 /**
 912  * set_consumer_device_supply: Bind a regulator to a symbolic supply
 913  * @rdev:         regulator source
 914  * @consumer_dev: device the supply applies to
 915  * @consumer_dev_name: dev_name() string for device supply applies to
 916  * @supply:       symbolic name for supply
 917  *
 918  * Allows platform initialisation code to map physical regulator
 919  * sources to symbolic names for supplies for use by devices.  Devices
 920  * should use these symbolic names to request regulators, avoiding the
 921  * need to provide board-specific regulator names as platform data.
 922  *
 923  * Only one of consumer_dev and consumer_dev_name may be specified.
 924  */
 925 static int set_consumer_device_supply(struct regulator_dev *rdev,
 926         struct device *consumer_dev, const char *consumer_dev_name,
 927         const char *supply)
 928 {
 929         struct regulator_map *node;
 930         int has_dev;
 931
 932         if (consumer_dev && consumer_dev_name)
 933                 return -EINVAL;
 934
 935         if (!consumer_dev_name && consumer_dev)
 936                 consumer_dev_name = dev_name(consumer_dev);
 937
 938         if (supply == NULL)
 939                 return -EINVAL;
 940
 941         if (consumer_dev_name != NULL)
 942                 has_dev = 1;
 943         else
 944                 has_dev = 0;
 945
 946         list_for_each_entry(node, &regulator_map_list, list) {
 947                 if (node->dev_name && consumer_dev_name) {
 948                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
 949                                 continue;
 950                 } else if (node->dev_name || consumer_dev_name) {
 951                         continue;
 952                 }
 953
 954                 if (strcmp(node->supply, supply) != 0)
 955                         continue;
 956
 957                 dev_dbg(consumer_dev, "%s/%s is '%s' supply; fail %s/%s\n",
 958                                 dev_name(&node->regulator->dev),
 959                                 node->regulator->desc->name,
 960                                 supply,
 961                                 dev_name(&rdev->dev), rdev_get_name(rdev));
 962                 return -EBUSY;
 963         }
 964
 965         node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
 966         if (node == NULL)
 967                 return -ENOMEM;
 968
 969         node->regulator = rdev;
 970         node->supply = supply;
 971
 972         if (has_dev) {
 973                 node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
 974                 if (node->dev_name == NULL) {
 975                         kfree(node);
 976                         return -ENOMEM;
 977                 }
 978         }
 979
 980         list_add(&node->list, &regulator_map_list);
 981         return 0;
 982 }
 983
 984 static void unset_regulator_supplies(struct regulator_dev *rdev)
 985 {
 986         struct regulator_map *node, *n;
 987
 988         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
 989                 if (rdev == node->regulator) {
 990                         list_del(&node->list);
 991                         kfree(node->dev_name);
 992                         kfree(node);
 993                 }
 994         }
 995 }
 996
 997 #define REG_STR_SIZE    32
 998
 999 static struct regulator *create_regulator(struct regulator_dev *rdev,
1000                                           struct device *dev,
1001                                           const char *supply_name)
1002 {
1003         struct regulator *regulator;
1004         char buf[REG_STR_SIZE];
1005         int err, size;
1006
1007         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1008         if (regulator == NULL)
1009                 return NULL;
1010
1011         mutex_lock(&rdev->mutex);
1012         regulator->rdev = rdev;
1013         list_add(&regulator->list, &rdev->consumer_list);
1014
1015         if (dev) {
1016                 /* create a 'requested_microamps_name' sysfs entry */
1017                 size = scnprintf(buf, REG_STR_SIZE, "microamps_requested_%s",
1018                         supply_name);
1019                 if (size >= REG_STR_SIZE)
1020                         goto overflow_err;
1021
1022                 regulator->dev = dev;
1023                 sysfs_attr_init(&regulator->dev_attr.attr);
1024                 regulator->dev_attr.attr.name = kstrdup(buf, GFP_KERNEL);
1025                 if (regulator->dev_attr.attr.name == NULL)
1026                         goto attr_name_err;
1027
1028                 regulator->dev_attr.attr.owner = THIS_MODULE;
1029                 regulator->dev_attr.attr.mode = 0444;
1030                 regulator->dev_attr.show = device_requested_uA_show;
1031                 err = device_create_file(dev, &regulator->dev_attr);
1032                 if (err < 0) {
1033                         printk(KERN_WARNING "%s: could not add regulator_dev"
1034                                 " load sysfs\n", __func__);
1035                         goto attr_name_err;
1036                 }
1037
1038                 /* also add a link to the device sysfs entry */
1039                 size = scnprintf(buf, REG_STR_SIZE, "%s-%s",
1040                                  dev->kobj.name, supply_name);
1041                 if (size >= REG_STR_SIZE)
1042                         goto attr_err;
1043
1044                 regulator->supply_name = kstrdup(buf, GFP_KERNEL);
1045                 if (regulator->supply_name == NULL)
1046                         goto attr_err;
1047
1048                 err = sysfs_create_link(&rdev->dev.kobj, &dev->kobj,
1049                                         buf);
1050                 if (err) {
1051                         printk(KERN_WARNING
1052                                "%s: could not add device link %s err %d\n",
1053                                __func__, dev->kobj.name, err);
1054                         device_remove_file(dev, &regulator->dev_attr);
1055                         goto link_name_err;
1056                 }
1057         }
1058         mutex_unlock(&rdev->mutex);
1059         return regulator;
1060 link_name_err:
1061         kfree(regulator->supply_name);
1062 attr_err:
1063         device_remove_file(regulator->dev, &regulator->dev_attr);
1064 attr_name_err:
1065         kfree(regulator->dev_attr.attr.name);
1066 overflow_err:
1067         list_del(&regulator->list);
1068         kfree(regulator);
1069         mutex_unlock(&rdev->mutex);
1070         return NULL;
1071 }
1072
1073 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1074 {
1075         if (!rdev->desc->ops->enable_time)
1076                 return 0;
1077         return rdev->desc->ops->enable_time(rdev);
1078 }
1079
1080 /* Internal regulator request function */
1081 static struct regulator *_regulator_get(struct device *dev, const char *id,
1082                                         int exclusive)
1083 {
1084         struct regulator_dev *rdev;
1085         struct regulator_map *map;
1086         struct regulator *regulator = ERR_PTR(-ENODEV);
1087         const char *devname = NULL;
1088         int ret;
1089
1090         if (id == NULL) {
1091                 printk(KERN_ERR "regulator: get() with no identifier\n");
1092                 return regulator;
1093         }
1094
1095         if (dev)
1096                 devname = dev_name(dev);
1097
1098         mutex_lock(&regulator_list_mutex);
1099
1100         list_for_each_entry(map, &regulator_map_list, list) {
1101                 /* If the mapping has a device set up it must match */
1102                 if (map->dev_name &&
1103                     (!devname || strcmp(map->dev_name, devname)))
1104                         continue;
1105
1106                 if (strcmp(map->supply, id) == 0) {
1107                         rdev = map->regulator;
1108                         goto found;
1109                 }
1110         }
1111
1112 #ifdef CONFIG_REGULATOR_DUMMY
1113         if (!devname)
1114                 devname = "deviceless";
1115
1116         /* If the board didn't flag that it was fully constrained then
1117          * substitute in a dummy regulator so consumers can continue.
1118          */
1119         if (!has_full_constraints) {
1120                 pr_warning("%s supply %s not found, using dummy regulator\n",
1121                            devname, id);
1122                 rdev = dummy_regulator_rdev;
1123                 goto found;
1124         }
1125 #endif
1126
1127         mutex_unlock(&regulator_list_mutex);
1128         return regulator;
1129
1130 found:
1131         if (rdev->exclusive) {
1132                 regulator = ERR_PTR(-EPERM);
1133                 goto out;
1134         }
1135
1136         if (exclusive && rdev->open_count) {
1137                 regulator = ERR_PTR(-EBUSY);
1138                 goto out;
1139         }
1140
1141         if (!try_module_get(rdev->owner))
1142                 goto out;
1143
1144         regulator = create_regulator(rdev, dev, id);
1145         if (regulator == NULL) {
1146                 regulator = ERR_PTR(-ENOMEM);
1147                 module_put(rdev->owner);
1148         }
1149
1150         rdev->open_count++;
1151         if (exclusive) {
1152                 rdev->exclusive = 1;
1153
1154                 ret = _regulator_is_enabled(rdev);
1155                 if (ret > 0)
1156                         rdev->use_count = 1;
1157                 else
1158                         rdev->use_count = 0;
1159         }
1160
1161 out:
1162         mutex_unlock(&regulator_list_mutex);
1163
1164         return regulator;
1165 }
1166
1167 /**
1168  * regulator_get - lookup and obtain a reference to a regulator.
1169  * @dev: device for regulator "consumer"
1170  * @id: Supply name or regulator ID.
1171  *
1172  * Returns a struct regulator corresponding to the regulator producer,
1173  * or IS_ERR() condition containing errno.
1174  *
1175  * Use of supply names configured via regulator_set_device_supply() is
1176  * strongly encouraged.  It is recommended that the supply name used
1177  * should match the name used for the supply and/or the relevant
1178  * device pins in the datasheet.
1179  */
1180 struct regulator *regulator_get(struct device *dev, const char *id)
1181 {
1182         return _regulator_get(dev, id, 0);
1183 }
1184 EXPORT_SYMBOL_GPL(regulator_get);
1185
1186 /**
1187  * regulator_get_exclusive - obtain exclusive access to a regulator.
1188  * @dev: device for regulator "consumer"
1189  * @id: Supply name or regulator ID.
1190  *
1191  * Returns a struct regulator corresponding to the regulator producer,
1192  * or IS_ERR() condition containing errno.  Other consumers will be
1193  * unable to obtain this reference is held and the use count for the
1194  * regulator will be initialised to reflect the current state of the
1195  * regulator.
1196  *
1197  * This is intended for use by consumers which cannot tolerate shared
1198  * use of the regulator such as those which need to force the
1199  * regulator off for correct operation of the hardware they are
1200  * controlling.
1201  *
1202  * Use of supply names configured via regulator_set_device_supply() is
1203  * strongly encouraged.  It is recommended that the supply name used
1204  * should match the name used for the supply and/or the relevant
1205  * device pins in the datasheet.
1206  */
1207 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
1208 {
1209         return _regulator_get(dev, id, 1);
1210 }
1211 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
1212
1213 /**
1214  * regulator_put - "free" the regulator source
1215  * @regulator: regulator source
1216  *
1217  * Note: drivers must ensure that all regulator_enable calls made on this
1218  * regulator source are balanced by regulator_disable calls prior to calling
1219  * this function.
1220  */
1221 void regulator_put(struct regulator *regulator)
1222 {
1223         struct regulator_dev *rdev;
1224
1225         if (regulator == NULL || IS_ERR(regulator))
1226                 return;
1227
1228         mutex_lock(&regulator_list_mutex);
1229         rdev = regulator->rdev;
1230
1231         /* remove any sysfs entries */
1232         if (regulator->dev) {
1233                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
1234                 kfree(regulator->supply_name);
1235                 device_remove_file(regulator->dev, &regulator->dev_attr);
1236                 kfree(regulator->dev_attr.attr.name);
1237         }
1238         list_del(&regulator->list);
1239         kfree(regulator);
1240
1241         rdev->open_count--;
1242         rdev->exclusive = 0;
1243
1244         module_put(rdev->owner);
1245         mutex_unlock(&regulator_list_mutex);
1246 }
1247 EXPORT_SYMBOL_GPL(regulator_put);
1248
1249 static int _regulator_can_change_status(struct regulator_dev *rdev)
1250 {
1251         if (!rdev->constraints)
1252                 return 0;
1253
1254         if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_STATUS)
1255                 return 1;
1256         else
1257                 return 0;
1258 }
1259
1260 /* locks held by regulator_enable() */
1261 static int _regulator_enable(struct regulator_dev *rdev)
1262 {
1263         int ret, delay;
1264
1265         /* do we need to enable the supply regulator first */
1266         if (rdev->supply) {
1267                 ret = _regulator_enable(rdev->supply);
1268                 if (ret < 0) {
1269                         printk(KERN_ERR "%s: failed to enable %s: %d\n",
1270                                __func__, rdev_get_name(rdev), ret);
1271                         return ret;
1272                 }
1273         }
1274
1275         /* check voltage and requested load before enabling */
1276         if (rdev->constraints &&
1277             (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS))
1278                 drms_uA_update(rdev);
1279
1280         if (rdev->use_count == 0) {
1281                 /* The regulator may on if it's not switchable or left on */
1282                 ret = _regulator_is_enabled(rdev);
1283                 if (ret == -EINVAL || ret == 0) {
1284                         if (!_regulator_can_change_status(rdev))
1285                                 return -EPERM;
1286
1287                         if (!rdev->desc->ops->enable)
1288                                 return -EINVAL;
1289
1290                         /* Query before enabling in case configuration
1291                          * dependant.  */
1292                         ret = _regulator_get_enable_time(rdev);
1293                         if (ret >= 0) {
1294                                 delay = ret;
1295                         } else {
1296                                 printk(KERN_WARNING
1297                                         "%s: enable_time() failed for %s: %d\n",
1298                                         __func__, rdev_get_name(rdev),
1299                                         ret);
1300                                 delay = 0;
1301                         }
1302
1303                         /* Allow the regulator to ramp; it would be useful
1304                          * to extend this for bulk operations so that the
1305                          * regulators can ramp together.  */
1306                         ret = rdev->desc->ops->enable(rdev);
1307                         if (ret < 0)
1308                                 return ret;
1309
1310                         if (delay >= 1000)
1311                                 mdelay(delay / 1000);
1312                         else if (delay)
1313                                 udelay(delay);
1314
1315                 } else if (ret < 0) {
1316                         printk(KERN_ERR "%s: is_enabled() failed for %s: %d\n",
1317                                __func__, rdev_get_name(rdev), ret);
1318                         return ret;
1319                 }
1320                 /* Fallthrough on positive return values - already enabled */
1321         }
1322
1323         rdev->use_count++;
1324
1325         return 0;
1326 }
1327
1328 /**
1329  * regulator_enable - enable regulator output
1330  * @regulator: regulator source
1331  *
1332  * Request that the regulator be enabled with the regulator output at
1333  * the predefined voltage or current value.  Calls to regulator_enable()
1334  * must be balanced with calls to regulator_disable().
1335  *
1336  * NOTE: the output value can be set by other drivers, boot loader or may be
1337  * hardwired in the regulator.
1338  */
1339 int regulator_enable(struct regulator *regulator)
1340 {
1341         struct regulator_dev *rdev = regulator->rdev;
1342         int ret = 0;
1343
1344         mutex_lock(&rdev->mutex);
1345         ret = _regulator_enable(rdev);
1346         mutex_unlock(&rdev->mutex);
1347         return ret;
1348 }
1349 EXPORT_SYMBOL_GPL(regulator_enable);
1350
1351 /* locks held by regulator_disable() */
1352 static int _regulator_disable(struct regulator_dev *rdev)
1353 {
1354         int ret = 0;
1355
1356         if (WARN(rdev->use_count <= 0,
1357                         "unbalanced disables for %s\n",
1358                         rdev_get_name(rdev)))
1359                 return -EIO;
1360
1361         /* are we the last user and permitted to disable ? */
1362         if (rdev->use_count == 1 &&
1363             (rdev->constraints && !rdev->constraints->always_on)) {
1364
1365                 /* we are last user */
1366                 if (_regulator_can_change_status(rdev) &&
1367                     rdev->desc->ops->disable) {
1368                         ret = rdev->desc->ops->disable(rdev);
1369                         if (ret < 0) {
1370                                 printk(KERN_ERR "%s: failed to disable %s\n",
1371                                        __func__, rdev_get_name(rdev));
1372                                 return ret;
1373                         }
1374
1375                         _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
1376                                              NULL);
1377                 }
1378
1379                 /* decrease our supplies ref count and disable if required */
1380                 if (rdev->supply)
1381                         _regulator_disable(rdev->supply);
1382
1383                 rdev->use_count = 0;
1384         } else if (rdev->use_count > 1) {
1385
1386                 if (rdev->constraints &&
1387                         (rdev->constraints->valid_ops_mask &
1388                         REGULATOR_CHANGE_DRMS))
1389                         drms_uA_update(rdev);
1390
1391                 rdev->use_count--;
1392         }
1393         return ret;
1394 }
1395
1396 /**
1397  * regulator_disable - disable regulator output
1398  * @regulator: regulator source
1399  *
1400  * Disable the regulator output voltage or current.  Calls to
1401  * regulator_enable() must be balanced with calls to
1402  * regulator_disable().
1403  *
1404  * NOTE: this will only disable the regulator output if no other consumer
1405  * devices have it enabled, the regulator device supports disabling and
1406  * machine constraints permit this operation.
1407  */
1408 int regulator_disable(struct regulator *regulator)
1409 {
1410         struct regulator_dev *rdev = regulator->rdev;
1411         int ret = 0;
1412
1413         mutex_lock(&rdev->mutex);
1414         ret = _regulator_disable(rdev);
1415         mutex_unlock(&rdev->mutex);
1416         return ret;
1417 }
1418 EXPORT_SYMBOL_GPL(regulator_disable);
1419
1420 /* locks held by regulator_force_disable() */
1421 static int _regulator_force_disable(struct regulator_dev *rdev)
1422 {
1423         int ret = 0;
1424
1425         /* force disable */
1426         if (rdev->desc->ops->disable) {
1427                 /* ah well, who wants to live forever... */
1428                 ret = rdev->desc->ops->disable(rdev);
1429                 if (ret < 0) {
1430                         printk(KERN_ERR "%s: failed to force disable %s\n",
1431                                __func__, rdev_get_name(rdev));
1432                         return ret;
1433                 }
1434                 /* notify other consumers that power has been forced off */
1435                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
1436                         REGULATOR_EVENT_DISABLE, NULL);
1437         }
1438
1439         /* decrease our supplies ref count and disable if required */
1440         if (rdev->supply)
1441                 _regulator_disable(rdev->supply);
1442
1443         rdev->use_count = 0;
1444         return ret;
1445 }
1446
1447 /**
1448  * regulator_force_disable - force disable regulator output
1449  * @regulator: regulator source
1450  *
1451  * Forcibly disable the regulator output voltage or current.
1452  * NOTE: this *will* disable the regulator output even if other consumer
1453  * devices have it enabled. This should be used for situations when device
1454  * damage will likely occur if the regulator is not disabled (e.g. over temp).
1455  */
1456 int regulator_force_disable(struct regulator *regulator)
1457 {
1458         int ret;
1459
1460         mutex_lock(&regulator->rdev->mutex);
1461         regulator->uA_load = 0;
1462         ret = _regulator_force_disable(regulator->rdev);
1463         mutex_unlock(&regulator->rdev->mutex);
1464         return ret;
1465 }
1466 EXPORT_SYMBOL_GPL(regulator_force_disable);
1467
1468 static int _regulator_is_enabled(struct regulator_dev *rdev)
1469 {
1470         /* If we don't know then assume that the regulator is always on */
1471         if (!rdev->desc->ops->is_enabled)
1472                 return 1;
1473
1474         return rdev->desc->ops->is_enabled(rdev);
1475 }
1476
1477 /**
1478  * regulator_is_enabled - is the regulator output enabled
1479  * @regulator: regulator source
1480  *
1481  * Returns positive if the regulator driver backing the source/client
1482  * has requested that the device be enabled, zero if it hasn't, else a
1483  * negative errno code.
1484  *
1485  * Note that the device backing this regulator handle can have multiple
1486  * users, so it might be enabled even if regulator_enable() was never
1487  * called for this particular source.
1488  */
1489 int regulator_is_enabled(struct regulator *regulator)
1490 {
1491         int ret;
1492
1493         mutex_lock(&regulator->rdev->mutex);
1494         ret = _regulator_is_enabled(regulator->rdev);
1495         mutex_unlock(&regulator->rdev->mutex);
1496
1497         return ret;
1498 }
1499 EXPORT_SYMBOL_GPL(regulator_is_enabled);
1500
1501 /**
1502  * regulator_count_voltages - count regulator_list_voltage() selectors
1503  * @regulator: regulator source
1504  *
1505  * Returns number of selectors, or negative errno.  Selectors are
1506  * numbered starting at zero, and typically correspond to bitfields
1507  * in hardware registers.
1508  */
1509 int regulator_count_voltages(struct regulator *regulator)
1510 {
1511         struct regulator_dev    *rdev = regulator->rdev;
1512
1513         return rdev->desc->n_voltages ? : -EINVAL;
1514 }
1515 EXPORT_SYMBOL_GPL(regulator_count_voltages);
1516
1517 /**
1518  * regulator_list_voltage - enumerate supported voltages
1519  * @regulator: regulator source
1520  * @selector: identify voltage to list
1521  * Context: can sleep
1522  *
1523  * Returns a voltage that can be passed to @regulator_set_voltage(),
1524  * zero if this selector code can't be used on this system, or a
1525  * negative errno.
1526  */
1527 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
1528 {
1529         struct regulator_dev    *rdev = regulator->rdev;
1530         struct regulator_ops    *ops = rdev->desc->ops;
1531         int                     ret;
1532
1533         if (!ops->list_voltage || selector >= rdev->desc->n_voltages)
1534                 return -EINVAL;
1535
1536         mutex_lock(&rdev->mutex);
1537         ret = ops->list_voltage(rdev, selector);
1538         mutex_unlock(&rdev->mutex);
1539
1540         if (ret > 0) {
1541                 if (ret < rdev->constraints->min_uV)
1542                         ret = 0;
1543                 else if (ret > rdev->constraints->max_uV)
1544                         ret = 0;
1545         }
1546
1547         return ret;
1548 }
1549 EXPORT_SYMBOL_GPL(regulator_list_voltage);
1550
1551 /**
1552  * regulator_is_supported_voltage - check if a voltage range can be supported
1553  *
1554  * @regulator: Regulator to check.
1555  * @min_uV: Minimum required voltage in uV.
1556  * @max_uV: Maximum required voltage in uV.
1557  *
1558  * Returns a boolean or a negative error code.
1559  */
1560 int regulator_is_supported_voltage(struct regulator *regulator,
1561                                    int min_uV, int max_uV)
1562 {
1563         int i, voltages, ret;
1564
1565         ret = regulator_count_voltages(regulator);
1566         if (ret < 0)
1567                 return ret;
1568         voltages = ret;
1569
1570         for (i = 0; i < voltages; i++) {
1571                 ret = regulator_list_voltage(regulator, i);
1572
1573                 if (ret >= min_uV && ret <= max_uV)
1574                         return 1;
1575         }
1576
1577         return 0;
1578 }
1579
1580 /**
1581  * regulator_set_voltage - set regulator output voltage
1582  * @regulator: regulator source
1583  * @min_uV: Minimum required voltage in uV
1584  * @max_uV: Maximum acceptable voltage in uV
1585  *
1586  * Sets a voltage regulator to the desired output voltage. This can be set
1587  * during any regulator state. IOW, regulator can be disabled or enabled.
1588  *
1589  * If the regulator is enabled then the voltage will change to the new value
1590  * immediately otherwise if the regulator is disabled the regulator will
1591  * output at the new voltage when enabled.
1592  *
1593  * NOTE: If the regulator is shared between several devices then the lowest
1594  * request voltage that meets the system constraints will be used.
1595  * Regulator system constraints must be set for this regulator before
1596  * calling this function otherwise this call will fail.
1597  */
1598 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
1599 {
1600         struct regulator_dev *rdev = regulator->rdev;
1601         int ret;
1602
1603         mutex_lock(&rdev->mutex);
1604
1605         /* sanity check */
1606         if (!rdev->desc->ops->set_voltage) {
1607                 ret = -EINVAL;
1608                 goto out;
1609         }
1610
1611         /* constraints check */
1612         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
1613         if (ret < 0)
1614                 goto out;
1615         regulator->min_uV = min_uV;
1616         regulator->max_uV = max_uV;
1617         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV);
1618
1619 out:
1620         _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE, NULL);
1621         mutex_unlock(&rdev->mutex);
1622         return ret;
1623 }
1624 EXPORT_SYMBOL_GPL(regulator_set_voltage);
1625
1626 static int _regulator_get_voltage(struct regulator_dev *rdev)
1627 {
1628         /* sanity check */
1629         if (rdev->desc->ops->get_voltage)
1630                 return rdev->desc->ops->get_voltage(rdev);
1631         else
1632                 return -EINVAL;
1633 }
1634
1635 /**
1636  * regulator_get_voltage - get regulator output voltage
1637  * @regulator: regulator source
1638  *
1639  * This returns the current regulator voltage in uV.
1640  *
1641  * NOTE: If the regulator is disabled it will return the voltage value. This
1642  * function should not be used to determine regulator state.
1643  */
1644 int regulator_get_voltage(struct regulator *regulator)
1645 {
1646         int ret;
1647
1648         mutex_lock(&regulator->rdev->mutex);
1649
1650         ret = _regulator_get_voltage(regulator->rdev);
1651
1652         mutex_unlock(&regulator->rdev->mutex);
1653
1654         return ret;
1655 }
1656 EXPORT_SYMBOL_GPL(regulator_get_voltage);
1657
1658 /**
1659  * regulator_set_current_limit - set regulator output current limit
1660  * @regulator: regulator source
1661  * @min_uA: Minimuum supported current in uA
1662  * @max_uA: Maximum supported current in uA
1663  *
1664  * Sets current sink to the desired output current. This can be set during
1665  * any regulator state. IOW, regulator can be disabled or enabled.
1666  *
1667  * If the regulator is enabled then the current will change to the new value
1668  * immediately otherwise if the regulator is disabled the regulator will
1669  * output at the new current when enabled.
1670  *
1671  * NOTE: Regulator system constraints must be set for this regulator before
1672  * calling this function otherwise this call will fail.
1673  */
1674 int regulator_set_current_limit(struct regulator *regulator,
1675                                int min_uA, int max_uA)
1676 {
1677         struct regulator_dev *rdev = regulator->rdev;
1678         int ret;
1679
1680         mutex_lock(&rdev->mutex);
1681
1682         /* sanity check */
1683         if (!rdev->desc->ops->set_current_limit) {
1684                 ret = -EINVAL;
1685                 goto out;
1686         }
1687
1688         /* constraints check */
1689         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
1690         if (ret < 0)
1691                 goto out;
1692
1693         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
1694 out:
1695         mutex_unlock(&rdev->mutex);
1696         return ret;
1697 }
1698 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
1699
1700 static int _regulator_get_current_limit(struct regulator_dev *rdev)
1701 {
1702         int ret;
1703
1704         mutex_lock(&rdev->mutex);
1705
1706         /* sanity check */
1707         if (!rdev->desc->ops->get_current_limit) {
1708                 ret = -EINVAL;
1709                 goto out;
1710         }
1711
1712         ret = rdev->desc->ops->get_current_limit(rdev);
1713 out:
1714         mutex_unlock(&rdev->mutex);
1715         return ret;
1716 }
1717
1718 /**
1719  * regulator_get_current_limit - get regulator output current
1720  * @regulator: regulator source
1721  *
1722  * This returns the current supplied by the specified current sink in uA.
1723  *
1724  * NOTE: If the regulator is disabled it will return the current value. This
1725  * function should not be used to determine regulator state.
1726  */
1727 int regulator_get_current_limit(struct regulator *regulator)
1728 {
1729         return _regulator_get_current_limit(regulator->rdev);
1730 }
1731 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
1732
1733 /**
1734  * regulator_set_mode - set regulator operating mode
1735  * @regulator: regulator source
1736  * @mode: operating mode - one of the REGULATOR_MODE constants
1737  *
1738  * Set regulator operating mode to increase regulator efficiency or improve
1739  * regulation performance.
1740  *
1741  * NOTE: Regulator system constraints must be set for this regulator before
1742  * calling this function otherwise this call will fail.
1743  */
1744 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
1745 {
1746         struct regulator_dev *rdev = regulator->rdev;
1747         int ret;
1748         int regulator_curr_mode;
1749
1750         mutex_lock(&rdev->mutex);
1751
1752         /* sanity check */
1753         if (!rdev->desc->ops->set_mode) {
1754                 ret = -EINVAL;
1755                 goto out;
1756         }
1757
1758         /* return if the same mode is requested */
1759         if (rdev->desc->ops->get_mode) {
1760                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
1761                 if (regulator_curr_mode == mode) {
1762                         ret = 0;
1763                         goto out;
1764                 }
1765         }
1766
1767         /* constraints check */
1768         ret = regulator_check_mode(rdev, mode);
1769         if (ret < 0)
1770                 goto out;
1771
1772         ret = rdev->desc->ops->set_mode(rdev, mode);
1773 out:
1774         mutex_unlock(&rdev->mutex);
1775         return ret;
1776 }
1777 EXPORT_SYMBOL_GPL(regulator_set_mode);
1778
1779 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
1780 {
1781         int ret;
1782
1783         mutex_lock(&rdev->mutex);
1784
1785         /* sanity check */
1786         if (!rdev->desc->ops->get_mode) {
1787                 ret = -EINVAL;
1788                 goto out;
1789         }
1790
1791         ret = rdev->desc->ops->get_mode(rdev);
1792 out:
1793         mutex_unlock(&rdev->mutex);
1794         return ret;
1795 }
1796
1797 /**
1798  * regulator_get_mode - get regulator operating mode
1799  * @regulator: regulator source
1800  *
1801  * Get the current regulator operating mode.
1802  */
1803 unsigned int regulator_get_mode(struct regulator *regulator)
1804 {
1805         return _regulator_get_mode(regulator->rdev);
1806 }
1807 EXPORT_SYMBOL_GPL(regulator_get_mode);
1808
1809 /**
1810  * regulator_set_optimum_mode - set regulator optimum operating mode
1811  * @regulator: regulator source
1812  * @uA_load: load current
1813  *
1814  * Notifies the regulator core of a new device load. This is then used by
1815  * DRMS (if enabled by constraints) to set the most efficient regulator
1816  * operating mode for the new regulator loading.
1817  *
1818  * Consumer devices notify their supply regulator of the maximum power
1819  * they will require (can be taken from device datasheet in the power
1820  * consumption tables) when they change operational status and hence power
1821  * state. Examples of operational state changes that can affect power
1822  * consumption are :-
1823  *
1824  *    o Device is opened / closed.
1825  *    o Device I/O is about to begin or has just finished.
1826  *    o Device is idling in between work.
1827  *
1828  * This information is also exported via sysfs to userspace.
1829  *
1830  * DRMS will sum the total requested load on the regulator and change
1831  * to the most efficient operating mode if platform constraints allow.
1832  *
1833  * Returns the new regulator mode or error.
1834  */
1835 int regulator_set_optimum_mode(struct regulator *regulator, int uA_load)
1836 {
1837         struct regulator_dev *rdev = regulator->rdev;
1838         struct regulator *consumer;
1839         int ret, output_uV, input_uV, total_uA_load = 0;
1840         unsigned int mode;
1841
1842         mutex_lock(&rdev->mutex);
1843
1844         regulator->uA_load = uA_load;
1845         ret = regulator_check_drms(rdev);
1846         if (ret < 0)
1847                 goto out;
1848         ret = -EINVAL;
1849
1850         /* sanity check */
1851         if (!rdev->desc->ops->get_optimum_mode)
1852                 goto out;
1853
1854         /* get output voltage */
1855         output_uV = rdev->desc->ops->get_voltage(rdev);
1856         if (output_uV <= 0) {
1857                 printk(KERN_ERR "%s: invalid output voltage found for %s\n",
1858                         __func__, rdev_get_name(rdev));
1859                 goto out;
1860         }
1861
1862         /* get input voltage */
1863         if (rdev->supply && rdev->supply->desc->ops->get_voltage)
1864                 input_uV = rdev->supply->desc->ops->get_voltage(rdev->supply);
1865         else
1866                 input_uV = rdev->constraints->input_uV;
1867         if (input_uV <= 0) {
1868                 printk(KERN_ERR "%s: invalid input voltage found for %s\n",
1869                         __func__, rdev_get_name(rdev));
1870                 goto out;
1871         }
1872
1873         /* calc total requested load for this regulator */
1874         list_for_each_entry(consumer, &rdev->consumer_list, list)
1875                 total_uA_load += consumer->uA_load;
1876
1877         mode = rdev->desc->ops->get_optimum_mode(rdev,
1878                                                  input_uV, output_uV,
1879                                                  total_uA_load);
1880         ret = regulator_check_mode(rdev, mode);
1881         if (ret < 0) {
1882                 printk(KERN_ERR "%s: failed to get optimum mode for %s @"
1883                         " %d uA %d -> %d uV\n", __func__, rdev_get_name(rdev),
1884                         total_uA_load, input_uV, output_uV);
1885                 goto out;
1886         }
1887
1888         ret = rdev->desc->ops->set_mode(rdev, mode);
1889         if (ret < 0) {
1890                 printk(KERN_ERR "%s: failed to set optimum mode %x for %s\n",
1891                         __func__, mode, rdev_get_name(rdev));
1892                 goto out;
1893         }
1894         ret = mode;
1895 out:
1896         mutex_unlock(&rdev->mutex);
1897         return ret;
1898 }
1899 EXPORT_SYMBOL_GPL(regulator_set_optimum_mode);
1900
1901 /**
1902  * regulator_register_notifier - register regulator event notifier
1903  * @regulator: regulator source
1904  * @nb: notifier block
1905  *
1906  * Register notifier block to receive regulator events.
1907  */
1908 int regulator_register_notifier(struct regulator *regulator,
1909                               struct notifier_block *nb)
1910 {
1911         return blocking_notifier_chain_register(&regulator->rdev->notifier,
1912                                                 nb);
1913 }
1914 EXPORT_SYMBOL_GPL(regulator_register_notifier);
1915
1916 /**
1917  * regulator_unregister_notifier - unregister regulator event notifier
1918  * @regulator: regulator source
1919  * @nb: notifier block
1920  *
1921  * Unregister regulator event notifier block.
1922  */
1923 int regulator_unregister_notifier(struct regulator *regulator,
1924                                 struct notifier_block *nb)
1925 {
1926         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
1927                                                   nb);
1928 }
1929 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
1930
1931 /* notify regulator consumers and downstream regulator consumers.
1932  * Note mutex must be held by caller.
1933  */
1934 static void _notifier_call_chain(struct regulator_dev *rdev,
1935                                   unsigned long event, void *data)
1936 {
1937         struct regulator_dev *_rdev;
1938
1939         /* call rdev chain first */
1940         blocking_notifier_call_chain(&rdev->notifier, event, NULL);
1941
1942         /* now notify regulator we supply */
1943         list_for_each_entry(_rdev, &rdev->supply_list, slist) {
1944                 mutex_lock(&_rdev->mutex);
1945                 _notifier_call_chain(_rdev, event, data);
1946                 mutex_unlock(&_rdev->mutex);
1947         }
1948 }
1949
1950 /**
1951  * regulator_bulk_get - get multiple regulator consumers
1952  *
1953  * @dev:           Device to supply
1954  * @num_consumers: Number of consumers to register
1955  * @consumers:     Configuration of consumers; clients are stored here.
1956  *
1957  * @return 0 on success, an errno on failure.
1958  *
1959  * This helper function allows drivers to get several regulator
1960  * consumers in one operation.  If any of the regulators cannot be
1961  * acquired then any regulators that were allocated will be freed
1962  * before returning to the caller.
1963  */
1964 int regulator_bulk_get(struct device *dev, int num_consumers,
1965                        struct regulator_bulk_data *consumers)
1966 {
1967         int i;
1968         int ret;
1969
1970         for (i = 0; i < num_consumers; i++)
1971                 consumers[i].consumer = NULL;
1972
1973         for (i = 0; i < num_consumers; i++) {
1974                 consumers[i].consumer = regulator_get(dev,
1975                                                       consumers[i].supply);
1976                 if (IS_ERR(consumers[i].consumer)) {
1977                         ret = PTR_ERR(consumers[i].consumer);
1978                         dev_err(dev, "Failed to get supply '%s': %d\n",
1979                                 consumers[i].supply, ret);
1980                         consumers[i].consumer = NULL;
1981                         goto err;
1982                 }
1983         }
1984
1985         return 0;
1986
1987 err:
1988         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
1989                 regulator_put(consumers[i].consumer);
1990
1991         return ret;
1992 }
1993 EXPORT_SYMBOL_GPL(regulator_bulk_get);
1994
1995 /**
1996  * regulator_bulk_enable - enable multiple regulator consumers
1997  *
1998  * @num_consumers: Number of consumers
1999  * @consumers:     Consumer data; clients are stored here.
2000  * @return         0 on success, an errno on failure
2001  *
2002  * This convenience API allows consumers to enable multiple regulator
2003  * clients in a single API call.  If any consumers cannot be enabled
2004  * then any others that were enabled will be disabled again prior to
2005  * return.
2006  */
2007 int regulator_bulk_enable(int num_consumers,
2008                           struct regulator_bulk_data *consumers)
2009 {
2010         int i;
2011         int ret;
2012
2013         for (i = 0; i < num_consumers; i++) {
2014                 ret = regulator_enable(consumers[i].consumer);
2015                 if (ret != 0)
2016                         goto err;
2017         }
2018
2019         return 0;
2020
2021 err:
2022         printk(KERN_ERR "Failed to enable %s: %d\n", consumers[i].supply, ret);
2023         for (--i; i >= 0; --i)
2024                 regulator_disable(consumers[i].consumer);
2025
2026         return ret;
2027 }
2028 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
2029
2030 /**
2031  * regulator_bulk_disable - disable multiple regulator consumers
2032  *
2033  * @num_consumers: Number of consumers
2034  * @consumers:     Consumer data; clients are stored here.
2035  * @return         0 on success, an errno on failure
2036  *
2037  * This convenience API allows consumers to disable multiple regulator
2038  * clients in a single API call.  If any consumers cannot be enabled
2039  * then any others that were disabled will be disabled again prior to
2040  * return.
2041  */
2042 int regulator_bulk_disable(int num_consumers,
2043                            struct regulator_bulk_data *consumers)
2044 {
2045         int i;
2046         int ret;
2047
2048         for (i = 0; i < num_consumers; i++) {
2049                 ret = regulator_disable(consumers[i].consumer);
2050                 if (ret != 0)
2051                         goto err;
2052         }
2053
2054         return 0;
2055
2056 err:
2057         printk(KERN_ERR "Failed to disable %s: %d\n", consumers[i].supply,
2058                ret);
2059         for (--i; i >= 0; --i)
2060                 regulator_enable(consumers[i].consumer);
2061
2062         return ret;
2063 }
2064 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
2065
2066 /**
2067  * regulator_bulk_free - free multiple regulator consumers
2068  *
2069  * @num_consumers: Number of consumers
2070  * @consumers:     Consumer data; clients are stored here.
2071  *
2072  * This convenience API allows consumers to free multiple regulator
2073  * clients in a single API call.
2074  */
2075 void regulator_bulk_free(int num_consumers,
2076                          struct regulator_bulk_data *consumers)
2077 {
2078         int i;
2079
2080         for (i = 0; i < num_consumers; i++) {
2081                 regulator_put(consumers[i].consumer);
2082                 consumers[i].consumer = NULL;
2083         }
2084 }
2085 EXPORT_SYMBOL_GPL(regulator_bulk_free);
2086
2087 /**
2088  * regulator_notifier_call_chain - call regulator event notifier
2089  * @rdev: regulator source
2090  * @event: notifier block
2091  * @data: callback-specific data.
2092  *
2093  * Called by regulator drivers to notify clients a regulator event has
2094  * occurred. We also notify regulator clients downstream.
2095  * Note lock must be held by caller.
2096  */
2097 int regulator_notifier_call_chain(struct regulator_dev *rdev,
2098                                   unsigned long event, void *data)
2099 {
2100         _notifier_call_chain(rdev, event, data);
2101         return NOTIFY_DONE;
2102
2103 }
2104 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
2105
2106 /**
2107  * regulator_mode_to_status - convert a regulator mode into a status
2108  *
2109  * @mode: Mode to convert
2110  *
2111  * Convert a regulator mode into a status.
2112  */
2113 int regulator_mode_to_status(unsigned int mode)
2114 {
2115         switch (mode) {
2116         case REGULATOR_MODE_FAST:
2117                 return REGULATOR_STATUS_FAST;
2118         case REGULATOR_MODE_NORMAL:
2119                 return REGULATOR_STATUS_NORMAL;
2120         case REGULATOR_MODE_IDLE:
2121                 return REGULATOR_STATUS_IDLE;
2122         case REGULATOR_STATUS_STANDBY:
2123                 return REGULATOR_STATUS_STANDBY;
2124         default:
2125                 return 0;
2126         }
2127 }
2128 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
2129
2130 /*
2131  * To avoid cluttering sysfs (and memory) with useless state, only
2132  * create attributes that can be meaningfully displayed.
2133  */
2134 static int add_regulator_attributes(struct regulator_dev *rdev)
2135 {
2136         struct device           *dev = &rdev->dev;
2137         struct regulator_ops    *ops = rdev->desc->ops;
2138         int                     status = 0;
2139
2140         /* some attributes need specific methods to be displayed */
2141         if (ops->get_voltage) {
2142                 status = device_create_file(dev, &dev_attr_microvolts);
2143                 if (status < 0)
2144                         return status;
2145         }
2146         if (ops->get_current_limit) {
2147                 status = device_create_file(dev, &dev_attr_microamps);
2148                 if (status < 0)
2149                         return status;
2150         }
2151         if (ops->get_mode) {
2152                 status = device_create_file(dev, &dev_attr_opmode);
2153                 if (status < 0)
2154                         return status;
2155         }
2156         if (ops->is_enabled) {
2157                 status = device_create_file(dev, &dev_attr_state);
2158                 if (status < 0)
2159                         return status;
2160         }
2161         if (ops->get_status) {
2162                 status = device_create_file(dev, &dev_attr_status);
2163                 if (status < 0)
2164                         return status;
2165         }
2166
2167         /* some attributes are type-specific */
2168         if (rdev->desc->type == REGULATOR_CURRENT) {
2169                 status = device_create_file(dev, &dev_attr_requested_microamps);
2170                 if (status < 0)
2171                         return status;
2172         }
2173
2174         /* all the other attributes exist to support constraints;
2175          * don't show them if there are no constraints, or if the
2176          * relevant supporting methods are missing.
2177          */
2178         if (!rdev->constraints)
2179                 return status;
2180
2181         /* constraints need specific supporting methods */
2182         if (ops->set_voltage) {
2183                 status = device_create_file(dev, &dev_attr_min_microvolts);
2184                 if (status < 0)
2185                         return status;
2186                 status = device_create_file(dev, &dev_attr_max_microvolts);
2187                 if (status < 0)
2188                         return status;
2189         }
2190         if (ops->set_current_limit) {
2191                 status = device_create_file(dev, &dev_attr_min_microamps);
2192                 if (status < 0)
2193                         return status;
2194                 status = device_create_file(dev, &dev_attr_max_microamps);
2195                 if (status < 0)
2196                         return status;
2197         }
2198
2199         /* suspend mode constraints need multiple supporting methods */
2200         if (!(ops->set_suspend_enable && ops->set_suspend_disable))
2201                 return status;
2202
2203         status = device_create_file(dev, &dev_attr_suspend_standby_state);
2204         if (status < 0)
2205                 return status;
2206         status = device_create_file(dev, &dev_attr_suspend_mem_state);
2207         if (status < 0)
2208                 return status;
2209         status = device_create_file(dev, &dev_attr_suspend_disk_state);
2210         if (status < 0)
2211                 return status;
2212
2213         if (ops->set_suspend_voltage) {
2214                 status = device_create_file(dev,
2215                                 &dev_attr_suspend_standby_microvolts);
2216                 if (status < 0)
2217                         return status;
2218                 status = device_create_file(dev,
2219                                 &dev_attr_suspend_mem_microvolts);
2220                 if (status < 0)
2221                         return status;
2222                 status = device_create_file(dev,
2223                                 &dev_attr_suspend_disk_microvolts);
2224                 if (status < 0)
2225                         return status;
2226         }
2227
2228         if (ops->set_suspend_mode) {
2229                 status = device_create_file(dev,
2230                                 &dev_attr_suspend_standby_mode);
2231                 if (status < 0)
2232                         return status;
2233                 status = device_create_file(dev,
2234                                 &dev_attr_suspend_mem_mode);
2235                 if (status < 0)
2236                         return status;
2237                 status = device_create_file(dev,
2238                                 &dev_attr_suspend_disk_mode);
2239                 if (status < 0)
2240                         return status;
2241         }
2242
2243         return status;
2244 }
2245
2246 /**
2247  * regulator_register - register regulator
2248  * @regulator_desc: regulator to register
2249  * @dev: struct device for the regulator
2250  * @init_data: platform provided init data, passed through by driver
2251  * @driver_data: private regulator data
2252  *
2253  * Called by regulator drivers to register a regulator.
2254  * Returns 0 on success.
2255  */
2256 struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
2257         struct device *dev, struct regulator_init_data *init_data,
2258         void *driver_data)
2259 {
2260         static atomic_t regulator_no = ATOMIC_INIT(0);
2261         struct regulator_dev *rdev;
2262         int ret, i;
2263
2264         if (regulator_desc == NULL)
2265                 return ERR_PTR(-EINVAL);
2266
2267         if (regulator_desc->name == NULL || regulator_desc->ops == NULL)
2268                 return ERR_PTR(-EINVAL);
2269
2270         if (regulator_desc->type != REGULATOR_VOLTAGE &&
2271             regulator_desc->type != REGULATOR_CURRENT)
2272                 return ERR_PTR(-EINVAL);
2273
2274         if (!init_data)
2275                 return ERR_PTR(-EINVAL);
2276
2277         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
2278         if (rdev == NULL)
2279                 return ERR_PTR(-ENOMEM);
2280
2281         mutex_lock(&regulator_list_mutex);
2282
2283         mutex_init(&rdev->mutex);
2284         rdev->reg_data = driver_data;
2285         rdev->owner = regulator_desc->owner;
2286         rdev->desc = regulator_desc;
2287         INIT_LIST_HEAD(&rdev->consumer_list);
2288         INIT_LIST_HEAD(&rdev->supply_list);
2289         INIT_LIST_HEAD(&rdev->list);
2290         INIT_LIST_HEAD(&rdev->slist);
2291         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
2292
2293         /* preform any regulator specific init */
2294         if (init_data->regulator_init) {
2295                 ret = init_data->regulator_init(rdev->reg_data);
2296                 if (ret < 0)
2297                         goto clean;
2298         }
2299
2300         /* register with sysfs */
2301         rdev->dev.class = &regulator_class;
2302         rdev->dev.parent = dev;
2303         dev_set_name(&rdev->dev, "regulator.%d",
2304                      atomic_inc_return(&regulator_no) - 1);
2305         ret = device_register(&rdev->dev);
2306         if (ret != 0)
2307                 goto clean;
2308
2309         dev_set_drvdata(&rdev->dev, rdev);
2310
2311         /* set regulator constraints */
2312         ret = set_machine_constraints(rdev, &init_data->constraints);
2313         if (ret < 0)
2314                 goto scrub;
2315
2316         /* add attributes supported by this regulator */
2317         ret = add_regulator_attributes(rdev);
2318         if (ret < 0)
2319                 goto scrub;
2320
2321         /* set supply regulator if it exists */
2322         if (init_data->supply_regulator && init_data->supply_regulator_dev) {
2323                 dev_err(dev,
2324                         "Supply regulator specified by both name and dev\n");
2325                 goto scrub;
2326         }
2327
2328         if (init_data->supply_regulator) {
2329                 struct regulator_dev *r;
2330                 int found = 0;
2331
2332                 list_for_each_entry(r, &regulator_list, list) {
2333                         if (strcmp(rdev_get_name(r),
2334                                    init_data->supply_regulator) == 0) {
2335                                 found = 1;
2336                                 break;
2337                         }
2338                 }
2339
2340                 if (!found) {
2341                         dev_err(dev, "Failed to find supply %s\n",
2342                                 init_data->supply_regulator);
2343                         goto scrub;
2344                 }
2345
2346                 ret = set_supply(rdev, r);
2347                 if (ret < 0)
2348                         goto scrub;
2349         }
2350
2351         if (init_data->supply_regulator_dev) {
2352                 dev_warn(dev, "Uses supply_regulator_dev instead of regulator_supply\n");
2353                 ret = set_supply(rdev,
2354                         dev_get_drvdata(init_data->supply_regulator_dev));
2355                 if (ret < 0)
2356                         goto scrub;
2357         }
2358
2359         /* add consumers devices */
2360         for (i = 0; i < init_data->num_consumer_supplies; i++) {
2361                 ret = set_consumer_device_supply(rdev,
2362                         init_data->consumer_supplies[i].dev,
2363                         init_data->consumer_supplies[i].dev_name,
2364                         init_data->consumer_supplies[i].supply);
2365                 if (ret < 0)
2366                         goto unset_supplies;
2367         }
2368
2369         list_add(&rdev->list, &regulator_list);
2370 out:
2371         mutex_unlock(&regulator_list_mutex);
2372         return rdev;
2373
2374 unset_supplies:
2375         unset_regulator_supplies(rdev);
2376
2377 scrub:
2378         device_unregister(&rdev->dev);
2379         /* device core frees rdev */
2380         rdev = ERR_PTR(ret);
2381         goto out;
2382
2383 clean:
2384         kfree(rdev);
2385         rdev = ERR_PTR(ret);
2386         goto out;
2387 }
2388 EXPORT_SYMBOL_GPL(regulator_register);
2389
2390 /**
2391  * regulator_unregister - unregister regulator
2392  * @rdev: regulator to unregister
2393  *
2394  * Called by regulator drivers to unregister a regulator.
2395  */
2396 void regulator_unregister(struct regulator_dev *rdev)
2397 {
2398         if (rdev == NULL)
2399                 return;
2400
2401         mutex_lock(&regulator_list_mutex);
2402         WARN_ON(rdev->open_count);
2403         unset_regulator_supplies(rdev);
2404         list_del(&rdev->list);
2405         if (rdev->supply)
2406                 sysfs_remove_link(&rdev->dev.kobj, "supply");
2407         device_unregister(&rdev->dev);
2408         mutex_unlock(&regulator_list_mutex);
2409 }
2410 EXPORT_SYMBOL_GPL(regulator_unregister);
2411
2412 /**
2413  * regulator_suspend_prepare - prepare regulators for system wide suspend
2414  * @state: system suspend state
2415  *
2416  * Configure each regulator with it's suspend operating parameters for state.
2417  * This will usually be called by machine suspend code prior to supending.
2418  */
2419 int regulator_suspend_prepare(suspend_state_t state)
2420 {
2421         struct regulator_dev *rdev;
2422         int ret = 0;
2423
2424         /* ON is handled by regulator active state */
2425         if (state == PM_SUSPEND_ON)
2426                 return -EINVAL;
2427
2428         mutex_lock(&regulator_list_mutex);
2429         list_for_each_entry(rdev, &regulator_list, list) {
2430
2431                 mutex_lock(&rdev->mutex);
2432                 ret = suspend_prepare(rdev, state);
2433                 mutex_unlock(&rdev->mutex);
2434
2435                 if (ret < 0) {
2436                         printk(KERN_ERR "%s: failed to prepare %s\n",
2437                                 __func__, rdev_get_name(rdev));
2438                         goto out;
2439                 }
2440         }
2441 out:
2442         mutex_unlock(&regulator_list_mutex);
2443         return ret;
2444 }
2445 EXPORT_SYMBOL_GPL(regulator_suspend_prepare);
2446
2447 /**
2448  * regulator_has_full_constraints - the system has fully specified constraints
2449  *
2450  * Calling this function will cause the regulator API to disable all
2451  * regulators which have a zero use count and don't have an always_on
2452  * constraint in a late_initcall.
2453  *
2454  * The intention is that this will become the default behaviour in a
2455  * future kernel release so users are encouraged to use this facility
2456  * now.
2457  */
2458 void regulator_has_full_constraints(void)
2459 {
2460         has_full_constraints = 1;
2461 }
2462 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
2463
2464 /**
2465  * rdev_get_drvdata - get rdev regulator driver data
2466  * @rdev: regulator
2467  *
2468  * Get rdev regulator driver private data. This call can be used in the
2469  * regulator driver context.
2470  */
2471 void *rdev_get_drvdata(struct regulator_dev *rdev)
2472 {
2473         return rdev->reg_data;
2474 }
2475 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
2476
2477 /**
2478  * regulator_get_drvdata - get regulator driver data
2479  * @regulator: regulator
2480  *
2481  * Get regulator driver private data. This call can be used in the consumer
2482  * driver context when non API regulator specific functions need to be called.
2483  */
2484 void *regulator_get_drvdata(struct regulator *regulator)
2485 {
2486         return regulator->rdev->reg_data;
2487 }
2488 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
2489
2490 /**
2491  * regulator_set_drvdata - set regulator driver data
2492  * @regulator: regulator
2493  * @data: data
2494  */
2495 void regulator_set_drvdata(struct regulator *regulator, void *data)
2496 {
2497         regulator->rdev->reg_data = data;
2498 }
2499 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
2500
2501 /**
2502  * regulator_get_id - get regulator ID
2503  * @rdev: regulator
2504  */
2505 int rdev_get_id(struct regulator_dev *rdev)
2506 {
2507         return rdev->desc->id;
2508 }
2509 EXPORT_SYMBOL_GPL(rdev_get_id);
2510
2511 struct device *rdev_get_dev(struct regulator_dev *rdev)
2512 {
2513         return &rdev->dev;
2514 }
2515 EXPORT_SYMBOL_GPL(rdev_get_dev);
2516
2517 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
2518 {
2519         return reg_init_data->driver_data;
2520 }
2521 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
2522
2523 static int __init regulator_init(void)
2524 {
2525         int ret;
2526
2527         printk(KERN_INFO "regulator: core version %s\n", REGULATOR_VERSION);
2528
2529         ret = class_register(&regulator_class);
2530
2531         regulator_dummy_init();
2532
2533         return ret;
2534 }
2535
2536 /* init early to allow our consumers to complete system booting */
2537 core_initcall(regulator_init);
2538
2539 static int __init regulator_init_complete(void)
2540 {
2541         struct regulator_dev *rdev;
2542         struct regulator_ops *ops;
2543         struct regulation_constraints *c;
2544         int enabled, ret;
2545         const char *name;
2546
2547         mutex_lock(&regulator_list_mutex);
2548
2549         /* If we have a full configuration then disable any regulators
2550          * which are not in use or always_on.  This will become the
2551          * default behaviour in the future.
2552          */
2553         list_for_each_entry(rdev, &regulator_list, list) {
2554                 ops = rdev->desc->ops;
2555                 c = rdev->constraints;
2556
2557                 name = rdev_get_name(rdev);
2558
2559                 if (!ops->disable || (c && c->always_on))
2560                         continue;
2561
2562                 mutex_lock(&rdev->mutex);
2563
2564                 if (rdev->use_count)
2565                         goto unlock;
2566
2567                 /* If we can't read the status assume it's on. */
2568                 if (ops->is_enabled)
2569                         enabled = ops->is_enabled(rdev);
2570                 else
2571                         enabled = 1;
2572
2573                 if (!enabled)
2574                         goto unlock;
2575
2576                 if (has_full_constraints) {
2577                         /* We log since this may kill the system if it
2578                          * goes wrong. */
2579                         printk(KERN_INFO "%s: disabling %s\n",
2580                                __func__, name);
2581                         ret = ops->disable(rdev);
2582                         if (ret != 0) {
2583                                 printk(KERN_ERR
2584                                        "%s: couldn't disable %s: %d\n",
2585                                        __func__, name, ret);
2586                         }
2587                 } else {
2588                         /* The intention is that in future we will
2589                          * assume that full constraints are provided
2590                          * so warn even if we aren't going to do
2591                          * anything here.
2592                          */
2593                         printk(KERN_WARNING
2594                                "%s: incomplete constraints, leaving %s on\n",
2595                                __func__, name);
2596                 }
2597
2598 unlock:
2599                 mutex_unlock(&rdev->mutex);
2600         }
2601
2602         mutex_unlock(&regulator_list_mutex);
2603
2604         return 0;
2605 }
2606 late_initcall(regulator_init_complete);