drivers/regulator/devres.c

   1 /*
   2  * devres.c  --  Voltage/Current Regulator framework devres implementation.
   3  *
   4  * Copyright 2013 Linaro Ltd
   5  *
   6  *  This program is free software; you can redistribute  it and/or modify it
   7  *  under  the terms of  the GNU General  Public License as published by the
   8  *  Free Software Foundation;  either version 2 of the  License, or (at your
   9  *  option) any later version.
  10  *
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/err.h>
  15 #include <linux/regmap.h>
  16 #include <linux/regulator/consumer.h>
  17 #include <linux/regulator/driver.h>
  18 #include <linux/module.h>
  19
  20 #include "internal.h"
  21
  22 enum {
  23         NORMAL_GET,
  24         EXCLUSIVE_GET,
  25         OPTIONAL_GET,
  26 };
  27
  28 static void devm_regulator_release(struct device *dev, void *res)
  29 {
  30         regulator_put(*(struct regulator **)res);
  31 }
  32
  33 static struct regulator *_devm_regulator_get(struct device *dev, const char *id,
  34                                              int get_type)
  35 {
  36         struct regulator **ptr, *regulator;
  37
  38         ptr = devres_alloc(devm_regulator_release, sizeof(*ptr), GFP_KERNEL);
  39         if (!ptr)
  40                 return ERR_PTR(-ENOMEM);
  41
  42         switch (get_type) {
  43         case NORMAL_GET:
  44                 regulator = regulator_get(dev, id);
  45                 break;
  46         case EXCLUSIVE_GET:
  47                 regulator = regulator_get_exclusive(dev, id);
  48                 break;
  49         case OPTIONAL_GET:
  50                 regulator = regulator_get_optional(dev, id);
  51                 break;
  52         default:
  53                 regulator = ERR_PTR(-EINVAL);
  54         }
  55
  56         if (!IS_ERR(regulator)) {
  57                 *ptr = regulator;
  58                 devres_add(dev, ptr);
  59         } else {
  60                 devres_free(ptr);
  61         }
  62
  63         return regulator;
  64 }
  65
  66 /**
  67  * devm_regulator_get - Resource managed regulator_get()
  68  * @dev: device for regulator "consumer"
  69  * @id: Supply name or regulator ID.
  70  *
  71  * Managed regulator_get(). Regulators returned from this function are
  72  * automatically regulator_put() on driver detach. See regulator_get() for more
  73  * information.
  74  */
  75 struct regulator *devm_regulator_get(struct device *dev, const char *id)
  76 {
  77         return _devm_regulator_get(dev, id, NORMAL_GET);
  78 }
  79 EXPORT_SYMBOL_GPL(devm_regulator_get);
  80
  81 /**
  82  * devm_regulator_get_exclusive - Resource managed regulator_get_exclusive()
  83  * @dev: device for regulator "consumer"
  84  * @id: Supply name or regulator ID.
  85  *
  86  * Managed regulator_get_exclusive(). Regulators returned from this function
  87  * are automatically regulator_put() on driver detach. See regulator_get() for
  88  * more information.
  89  */
  90 struct regulator *devm_regulator_get_exclusive(struct device *dev,
  91                                                const char *id)
  92 {
  93         return _devm_regulator_get(dev, id, EXCLUSIVE_GET);
  94 }
  95 EXPORT_SYMBOL_GPL(devm_regulator_get_exclusive);
  96
  97 /**
  98  * devm_regulator_get_optional - Resource managed regulator_get_optional()
  99  * @dev: device for regulator "consumer"
 100  * @id: Supply name or regulator ID.
 101  *
 102  * Managed regulator_get_optional(). Regulators returned from this
 103  * function are automatically regulator_put() on driver detach. See
 104  * regulator_get_optional() for more information.
 105  */
 106 struct regulator *devm_regulator_get_optional(struct device *dev,
 107                                               const char *id)
 108 {
 109         return _devm_regulator_get(dev, id, OPTIONAL_GET);
 110 }
 111 EXPORT_SYMBOL_GPL(devm_regulator_get_optional);
 112
 113 static int devm_regulator_match(struct device *dev, void *res, void *data)
 114 {
 115         struct regulator **r = res;
 116         if (!r || !*r) {
 117                 WARN_ON(!r || !*r);
 118                 return 0;
 119         }
 120         return *r == data;
 121 }
 122
 123 /**
 124  * devm_regulator_put - Resource managed regulator_put()
 125  * @regulator: regulator to free
 126  *
 127  * Deallocate a regulator allocated with devm_regulator_get(). Normally
 128  * this function will not need to be called and the resource management
 129  * code will ensure that the resource is freed.
 130  */
 131 void devm_regulator_put(struct regulator *regulator)
 132 {
 133         int rc;
 134
 135         rc = devres_release(regulator->dev, devm_regulator_release,
 136                             devm_regulator_match, regulator);
 137         if (rc != 0)
 138                 WARN_ON(rc);
 139 }
 140 EXPORT_SYMBOL_GPL(devm_regulator_put);
 141
 142 /**
 143  * devm_regulator_bulk_get - managed get multiple regulator consumers
 144  *
 145  * @dev:           Device to supply
 146  * @num_consumers: Number of consumers to register
 147  * @consumers:     Configuration of consumers; clients are stored here.
 148  *
 149  * @return 0 on success, an errno on failure.
 150  *
 151  * This helper function allows drivers to get several regulator
 152  * consumers in one operation with management, the regulators will
 153  * automatically be freed when the device is unbound.  If any of the
 154  * regulators cannot be acquired then any regulators that were
 155  * allocated will be freed before returning to the caller.
 156  */
 157 int devm_regulator_bulk_get(struct device *dev, int num_consumers,
 158                             struct regulator_bulk_data *consumers)
 159 {
 160         int i;
 161         int ret;
 162
 163         for (i = 0; i < num_consumers; i++)
 164                 consumers[i].consumer = NULL;
 165
 166         for (i = 0; i < num_consumers; i++) {
 167                 consumers[i].consumer = devm_regulator_get(dev,
 168                                                            consumers[i].supply);
 169                 if (IS_ERR(consumers[i].consumer)) {
 170                         ret = PTR_ERR(consumers[i].consumer);
 171                         dev_err(dev, "Failed to get supply '%s': %d\n",
 172                                 consumers[i].supply, ret);
 173                         consumers[i].consumer = NULL;
 174                         goto err;
 175                 }
 176         }
 177
 178         return 0;
 179
 180 err:
 181         for (i = 0; i < num_consumers && consumers[i].consumer; i++)
 182                 devm_regulator_put(consumers[i].consumer);
 183
 184         return ret;
 185 }
 186 EXPORT_SYMBOL_GPL(devm_regulator_bulk_get);
 187
 188 static void devm_rdev_release(struct device *dev, void *res)
 189 {
 190         regulator_unregister(*(struct regulator_dev **)res);
 191 }
 192
 193 /**
 194  * devm_regulator_register - Resource managed regulator_register()
 195  * @regulator_desc: regulator to register
 196  * @config: runtime configuration for regulator
 197  *
 198  * Called by regulator drivers to register a regulator.  Returns a
 199  * valid pointer to struct regulator_dev on success or an ERR_PTR() on
 200  * error.  The regulator will automatically be released when the device
 201  * is unbound.
 202  */
 203 struct regulator_dev *devm_regulator_register(struct device *dev,
 204                                   const struct regulator_desc *regulator_desc,
 205                                   const struct regulator_config *config)
 206 {
 207         struct regulator_dev **ptr, *rdev;
 208
 209         ptr = devres_alloc(devm_rdev_release, sizeof(*ptr),
 210                            GFP_KERNEL);
 211         if (!ptr)
 212                 return ERR_PTR(-ENOMEM);
 213
 214         rdev = regulator_register(regulator_desc, config);
 215         if (!IS_ERR(rdev)) {
 216                 *ptr = rdev;
 217                 devres_add(dev, ptr);
 218         } else {
 219                 devres_free(ptr);
 220         }
 221
 222         return rdev;
 223 }
 224 EXPORT_SYMBOL_GPL(devm_regulator_register);
 225
 226 static int devm_rdev_match(struct device *dev, void *res, void *data)
 227 {
 228         struct regulator_dev **r = res;
 229         if (!r || !*r) {
 230                 WARN_ON(!r || !*r);
 231                 return 0;
 232         }
 233         return *r == data;
 234 }
 235
 236 /**
 237  * devm_regulator_unregister - Resource managed regulator_unregister()
 238  * @regulator: regulator to free
 239  *
 240  * Unregister a regulator registered with devm_regulator_register().
 241  * Normally this function will not need to be called and the resource
 242  * management code will ensure that the resource is freed.
 243  */
 244 void devm_regulator_unregister(struct device *dev, struct regulator_dev *rdev)
 245 {
 246         int rc;
 247
 248         rc = devres_release(dev, devm_rdev_release, devm_rdev_match, rdev);
 249         if (rc != 0)
 250                 WARN_ON(rc);
 251 }
 252 EXPORT_SYMBOL_GPL(devm_regulator_unregister);
 253
 254 struct regulator_supply_alias_match {
 255         struct device *dev;
 256         const char *id;
 257 };
 258
 259 static int devm_regulator_match_supply_alias(struct device *dev, void *res,
 260                                              void *data)
 261 {
 262         struct regulator_supply_alias_match *match = res;
 263         struct regulator_supply_alias_match *target = data;
 264
 265         return match->dev == target->dev && strcmp(match->id, target->id) == 0;
 266 }
 267
 268 static void devm_regulator_destroy_supply_alias(struct device *dev, void *res)
 269 {
 270         struct regulator_supply_alias_match *match = res;
 271
 272         regulator_unregister_supply_alias(match->dev, match->id);
 273 }
 274
 275 /**
 276  * devm_regulator_register_supply_alias - Resource managed
 277  * regulator_register_supply_alias()
 278  *
 279  * @dev: device that will be given as the regulator "consumer"
 280  * @id: Supply name or regulator ID
 281  * @alias_dev: device that should be used to lookup the supply
 282  * @alias_id: Supply name or regulator ID that should be used to lookup the
 283  * supply
 284  *
 285  * The supply alias will automatically be unregistered when the source
 286  * device is unbound.
 287  */
 288 int devm_regulator_register_supply_alias(struct device *dev, const char *id,
 289                                          struct device *alias_dev,
 290                                          const char *alias_id)
 291 {
 292         struct regulator_supply_alias_match *match;
 293         int ret;
 294
 295         match = devres_alloc(devm_regulator_destroy_supply_alias,
 296                            sizeof(struct regulator_supply_alias_match),
 297                            GFP_KERNEL);
 298         if (!match)
 299                 return -ENOMEM;
 300
 301         match->dev = dev;
 302         match->id = id;
 303
 304         ret = regulator_register_supply_alias(dev, id, alias_dev, alias_id);
 305         if (ret < 0) {
 306                 devres_free(match);
 307                 return ret;
 308         }
 309
 310         devres_add(dev, match);
 311
 312         return 0;
 313 }
 314 EXPORT_SYMBOL_GPL(devm_regulator_register_supply_alias);
 315
 316 /**
 317  * devm_regulator_unregister_supply_alias - Resource managed
 318  * regulator_unregister_supply_alias()
 319  *
 320  * @dev: device that will be given as the regulator "consumer"
 321  * @id: Supply name or regulator ID
 322  *
 323  * Unregister an alias registered with
 324  * devm_regulator_register_supply_alias(). Normally this function
 325  * will not need to be called and the resource management code
 326  * will ensure that the resource is freed.
 327  */
 328 void devm_regulator_unregister_supply_alias(struct device *dev, const char *id)
 329 {
 330         struct regulator_supply_alias_match match;
 331         int rc;
 332
 333         match.dev = dev;
 334         match.id = id;
 335
 336         rc = devres_release(dev, devm_regulator_destroy_supply_alias,
 337                             devm_regulator_match_supply_alias, &match);
 338         if (rc != 0)
 339                 WARN_ON(rc);
 340 }
 341 EXPORT_SYMBOL_GPL(devm_regulator_unregister_supply_alias);
 342
 343 /**
 344  * devm_regulator_bulk_register_supply_alias - Managed register
 345  * multiple aliases
 346  *
 347  * @dev: device that will be given as the regulator "consumer"
 348  * @id: List of supply names or regulator IDs
 349  * @alias_dev: device that should be used to lookup the supply
 350  * @alias_id: List of supply names or regulator IDs that should be used to
 351  * lookup the supply
 352  * @num_id: Number of aliases to register
 353  *
 354  * @return 0 on success, an errno on failure.
 355  *
 356  * This helper function allows drivers to register several supply
 357  * aliases in one operation, the aliases will be automatically
 358  * unregisters when the source device is unbound.  If any of the
 359  * aliases cannot be registered any aliases that were registered
 360  * will be removed before returning to the caller.
 361  */
 362 int devm_regulator_bulk_register_supply_alias(struct device *dev,
 363                                               const char **id,
 364                                               struct device *alias_dev,
 365                                               const char **alias_id,
 366                                               int num_id)
 367 {
 368         int i;
 369         int ret;
 370
 371         for (i = 0; i < num_id; ++i) {
 372                 ret = devm_regulator_register_supply_alias(dev, id[i],
 373                                                            alias_dev,
 374                                                            alias_id[i]);
 375                 if (ret < 0)
 376                         goto err;
 377         }
 378
 379         return 0;
 380
 381 err:
 382         dev_err(dev,
 383                 "Failed to create supply alias %s,%s -> %s,%s\n",
 384                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
 385
 386         while (--i >= 0)
 387                 devm_regulator_unregister_supply_alias(dev, id[i]);
 388
 389         return ret;
 390 }
 391 EXPORT_SYMBOL_GPL(devm_regulator_bulk_register_supply_alias);
 392
 393 /**
 394  * devm_regulator_bulk_unregister_supply_alias - Managed unregister
 395  * multiple aliases
 396  *
 397  * @dev: device that will be given as the regulator "consumer"
 398  * @id: List of supply names or regulator IDs
 399  * @num_id: Number of aliases to unregister
 400  *
 401  * Unregister aliases registered with
 402  * devm_regulator_bulk_register_supply_alias(). Normally this function
 403  * will not need to be called and the resource management code
 404  * will ensure that the resource is freed.
 405  */
 406 void devm_regulator_bulk_unregister_supply_alias(struct device *dev,
 407                                                  const char **id,
 408                                                  int num_id)
 409 {
 410         int i;
 411
 412         for (i = 0; i < num_id; ++i)
 413                 devm_regulator_unregister_supply_alias(dev, id[i]);
 414 }
 415 EXPORT_SYMBOL_GPL(devm_regulator_bulk_unregister_supply_alias);