net/rfkill/rfkill.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the
  17  * Free Software Foundation, Inc.,
  18  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/init.h>
  24 #include <linux/workqueue.h>
  25 #include <linux/capability.h>
  26 #include <linux/list.h>
  27 #include <linux/mutex.h>
  28 #include <linux/rfkill.h>
  29
  30 /* Get declaration of rfkill_switch_all() to shut up sparse. */
  31 #include "rfkill-input.h"
  32
  33
  34 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  35 MODULE_VERSION("1.0");
  36 MODULE_DESCRIPTION("RF switch support");
  37 MODULE_LICENSE("GPL");
  38
  39 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
  40 static DEFINE_MUTEX(rfkill_mutex);
  41
  42 static unsigned int rfkill_default_state = RFKILL_STATE_UNBLOCKED;
  43 module_param_named(default_state, rfkill_default_state, uint, 0444);
  44 MODULE_PARM_DESC(default_state,
  45                  "Default initial state for all radio types, 0 = radio off");
  46
  47 static enum rfkill_state rfkill_states[RFKILL_TYPE_MAX];
  48
  49 static BLOCKING_NOTIFIER_HEAD(rfkill_notifier_list);
  50
  51
  52 /**
  53  * register_rfkill_notifier - Add notifier to rfkill notifier chain
  54  * @nb: pointer to the new entry to add to the chain
  55  *
  56  * See blocking_notifier_chain_register() for return value and further
  57  * observations.
  58  *
  59  * Adds a notifier to the rfkill notifier chain.  The chain will be
  60  * called with a pointer to the relevant rfkill structure as a parameter,
  61  * refer to include/linux/rfkill.h for the possible events.
  62  *
  63  * Notifiers added to this chain are to always return NOTIFY_DONE.  This
  64  * chain is a blocking notifier chain: notifiers can sleep.
  65  *
  66  * Calls to this chain may have been done through a workqueue.  One must
  67  * assume unordered asynchronous behaviour, there is no way to know if
  68  * actions related to the event that generated the notification have been
  69  * carried out already.
  70  */
  71 int register_rfkill_notifier(struct notifier_block *nb)
  72 {
  73         return blocking_notifier_chain_register(&rfkill_notifier_list, nb);
  74 }
  75 EXPORT_SYMBOL_GPL(register_rfkill_notifier);
  76
  77 /**
  78  * unregister_rfkill_notifier - remove notifier from rfkill notifier chain
  79  * @nb: pointer to the entry to remove from the chain
  80  *
  81  * See blocking_notifier_chain_unregister() for return value and further
  82  * observations.
  83  *
  84  * Removes a notifier from the rfkill notifier chain.
  85  */
  86 int unregister_rfkill_notifier(struct notifier_block *nb)
  87 {
  88         return blocking_notifier_chain_unregister(&rfkill_notifier_list, nb);
  89 }
  90 EXPORT_SYMBOL_GPL(unregister_rfkill_notifier);
  91
  92
  93 static void rfkill_led_trigger(struct rfkill *rfkill,
  94                                enum rfkill_state state)
  95 {
  96 #ifdef CONFIG_RFKILL_LEDS
  97         struct led_trigger *led = &rfkill->led_trigger;
  98
  99         if (!led->name)
 100                 return;
 101         if (state != RFKILL_STATE_UNBLOCKED)
 102                 led_trigger_event(led, LED_OFF);
 103         else
 104                 led_trigger_event(led, LED_FULL);
 105 #endif /* CONFIG_RFKILL_LEDS */
 106 }
 107
 108 static void notify_rfkill_state_change(struct rfkill *rfkill)
 109 {
 110         blocking_notifier_call_chain(&rfkill_notifier_list,
 111                         RFKILL_STATE_CHANGED,
 112                         rfkill);
 113 }
 114
 115 static void update_rfkill_state(struct rfkill *rfkill)
 116 {
 117         enum rfkill_state newstate, oldstate;
 118
 119         if (rfkill->get_state) {
 120                 mutex_lock(&rfkill->mutex);
 121                 if (!rfkill->get_state(rfkill->data, &newstate)) {
 122                         oldstate = rfkill->state;
 123                         rfkill->state = newstate;
 124                         if (oldstate != newstate)
 125                                 notify_rfkill_state_change(rfkill);
 126                 }
 127                 mutex_unlock(&rfkill->mutex);
 128         }
 129 }
 130
 131 /**
 132  * rfkill_toggle_radio - wrapper for toggle_radio hook
 133  *
 134  * @rfkill: the rfkill struct to use
 135  * @force: calls toggle_radio even if cache says it is not needed,
 136  *      and also makes sure notifications of the state will be
 137  *      sent even if it didn't change
 138  * @state: the new state to call toggle_radio() with
 139  *
 140  * Calls rfkill->toggle_radio, enforcing the API for toggle_radio
 141  * calls and handling all the red tape such as issuing notifications
 142  * if the call is successful.
 143  *
 144  * Note that @force cannot override a (possibly cached) state of
 145  * RFKILL_STATE_HARD_BLOCKED.  Any device making use of
 146  * RFKILL_STATE_HARD_BLOCKED implements either get_state() or
 147  * rfkill_force_state(), so the cache either is bypassed or valid.
 148  *
 149  * Note that we do call toggle_radio for RFKILL_STATE_SOFT_BLOCKED
 150  * even if the radio is in RFKILL_STATE_HARD_BLOCKED state, so as to
 151  * give the driver a hint that it should double-BLOCK the transmitter.
 152  *
 153  * Caller must have acquired rfkill->mutex.
 154  */
 155 static int rfkill_toggle_radio(struct rfkill *rfkill,
 156                                 enum rfkill_state state,
 157                                 int force)
 158 {
 159         int retval = 0;
 160         enum rfkill_state oldstate, newstate;
 161
 162         oldstate = rfkill->state;
 163
 164         if (rfkill->get_state && !force &&
 165             !rfkill->get_state(rfkill->data, &newstate))
 166                 rfkill->state = newstate;
 167
 168         switch (state) {
 169         case RFKILL_STATE_HARD_BLOCKED:
 170                 /* typically happens when refreshing hardware state,
 171                  * such as on resume */
 172                 state = RFKILL_STATE_SOFT_BLOCKED;
 173                 break;
 174         case RFKILL_STATE_UNBLOCKED:
 175                 /* force can't override this, only rfkill_force_state() can */
 176                 if (rfkill->state == RFKILL_STATE_HARD_BLOCKED)
 177                         return -EPERM;
 178                 break;
 179         case RFKILL_STATE_SOFT_BLOCKED:
 180                 /* nothing to do, we want to give drivers the hint to double
 181                  * BLOCK even a transmitter that is already in state
 182                  * RFKILL_STATE_HARD_BLOCKED */
 183                 break;
 184         }
 185
 186         if (force || state != rfkill->state) {
 187                 retval = rfkill->toggle_radio(rfkill->data, state);
 188                 /* never allow a HARD->SOFT downgrade! */
 189                 if (!retval && rfkill->state != RFKILL_STATE_HARD_BLOCKED)
 190                         rfkill->state = state;
 191         }
 192
 193         if (force || rfkill->state != oldstate) {
 194                 rfkill_led_trigger(rfkill, rfkill->state);
 195                 notify_rfkill_state_change(rfkill);
 196         }
 197
 198         return retval;
 199 }
 200
 201 /**
 202  * rfkill_switch_all - Toggle state of all switches of given type
 203  * @type: type of interfaces to be affeceted
 204  * @state: the new state
 205  *
 206  * This function toggles state of all switches of given type unless
 207  * a specific switch is claimed by userspace in which case it is
 208  * left alone.
 209  */
 210 void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
 211 {
 212         struct rfkill *rfkill;
 213
 214         mutex_lock(&rfkill_mutex);
 215
 216         rfkill_states[type] = state;
 217
 218         list_for_each_entry(rfkill, &rfkill_list, node) {
 219                 if ((!rfkill->user_claim) && (rfkill->type == type)) {
 220                         mutex_lock(&rfkill->mutex);
 221                         rfkill_toggle_radio(rfkill, state, 0);
 222                         mutex_unlock(&rfkill->mutex);
 223                 }
 224         }
 225
 226         mutex_unlock(&rfkill_mutex);
 227 }
 228 EXPORT_SYMBOL(rfkill_switch_all);
 229
 230 /**
 231  * rfkill_epo - emergency power off all transmitters
 232  *
 233  * This kicks all rfkill devices to RFKILL_STATE_SOFT_BLOCKED, ignoring
 234  * everything in its path but rfkill_mutex and rfkill->mutex.
 235  */
 236 void rfkill_epo(void)
 237 {
 238         struct rfkill *rfkill;
 239
 240         mutex_lock(&rfkill_mutex);
 241         list_for_each_entry(rfkill, &rfkill_list, node) {
 242                 mutex_lock(&rfkill->mutex);
 243                 rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1);
 244                 mutex_unlock(&rfkill->mutex);
 245         }
 246         mutex_unlock(&rfkill_mutex);
 247 }
 248 EXPORT_SYMBOL_GPL(rfkill_epo);
 249
 250 /**
 251  * rfkill_force_state - Force the internal rfkill radio state
 252  * @rfkill: pointer to the rfkill class to modify.
 253  * @state: the current radio state the class should be forced to.
 254  *
 255  * This function updates the internal state of the radio cached
 256  * by the rfkill class.  It should be used when the driver gets
 257  * a notification by the firmware/hardware of the current *real*
 258  * state of the radio rfkill switch.
 259  *
 260  * Devices which are subject to external changes on their rfkill
 261  * state (such as those caused by a hardware rfkill line) MUST
 262  * have their driver arrange to call rfkill_force_state() as soon
 263  * as possible after such a change.
 264  *
 265  * This function may not be called from an atomic context.
 266  */
 267 int rfkill_force_state(struct rfkill *rfkill, enum rfkill_state state)
 268 {
 269         enum rfkill_state oldstate;
 270
 271         if (state != RFKILL_STATE_SOFT_BLOCKED &&
 272             state != RFKILL_STATE_UNBLOCKED &&
 273             state != RFKILL_STATE_HARD_BLOCKED)
 274                 return -EINVAL;
 275
 276         mutex_lock(&rfkill->mutex);
 277
 278         oldstate = rfkill->state;
 279         rfkill->state = state;
 280
 281         if (state != oldstate)
 282                 notify_rfkill_state_change(rfkill);
 283
 284         mutex_unlock(&rfkill->mutex);
 285
 286         return 0;
 287 }
 288 EXPORT_SYMBOL(rfkill_force_state);
 289
 290 static ssize_t rfkill_name_show(struct device *dev,
 291                                 struct device_attribute *attr,
 292                                 char *buf)
 293 {
 294         struct rfkill *rfkill = to_rfkill(dev);
 295
 296         return sprintf(buf, "%s\n", rfkill->name);
 297 }
 298
 299 static const char *rfkill_get_type_str(enum rfkill_type type)
 300 {
 301         switch (type) {
 302         case RFKILL_TYPE_WLAN:
 303                 return "wlan";
 304         case RFKILL_TYPE_BLUETOOTH:
 305                 return "bluetooth";
 306         case RFKILL_TYPE_UWB:
 307                 return "ultrawideband";
 308         case RFKILL_TYPE_WIMAX:
 309                 return "wimax";
 310         case RFKILL_TYPE_WWAN:
 311                 return "wwan";
 312         default:
 313                 BUG();
 314         }
 315 }
 316
 317 static ssize_t rfkill_type_show(struct device *dev,
 318                                 struct device_attribute *attr,
 319                                 char *buf)
 320 {
 321         struct rfkill *rfkill = to_rfkill(dev);
 322
 323         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 324 }
 325
 326 static ssize_t rfkill_state_show(struct device *dev,
 327                                  struct device_attribute *attr,
 328                                  char *buf)
 329 {
 330         struct rfkill *rfkill = to_rfkill(dev);
 331
 332         update_rfkill_state(rfkill);
 333         return sprintf(buf, "%d\n", rfkill->state);
 334 }
 335
 336 static ssize_t rfkill_state_store(struct device *dev,
 337                                   struct device_attribute *attr,
 338                                   const char *buf, size_t count)
 339 {
 340         struct rfkill *rfkill = to_rfkill(dev);
 341         unsigned int state = simple_strtoul(buf, NULL, 0);
 342         int error;
 343
 344         if (!capable(CAP_NET_ADMIN))
 345                 return -EPERM;
 346
 347         /* RFKILL_STATE_HARD_BLOCKED is illegal here... */
 348         if (state != RFKILL_STATE_UNBLOCKED &&
 349             state != RFKILL_STATE_SOFT_BLOCKED)
 350                 return -EINVAL;
 351
 352         if (mutex_lock_interruptible(&rfkill->mutex))
 353                 return -ERESTARTSYS;
 354         error = rfkill_toggle_radio(rfkill, state, 0);
 355         mutex_unlock(&rfkill->mutex);
 356
 357         return error ? error : count;
 358 }
 359
 360 static ssize_t rfkill_claim_show(struct device *dev,
 361                                  struct device_attribute *attr,
 362                                  char *buf)
 363 {
 364         struct rfkill *rfkill = to_rfkill(dev);
 365
 366         return sprintf(buf, "%d", rfkill->user_claim);
 367 }
 368
 369 static ssize_t rfkill_claim_store(struct device *dev,
 370                                   struct device_attribute *attr,
 371                                   const char *buf, size_t count)
 372 {
 373         struct rfkill *rfkill = to_rfkill(dev);
 374         bool claim = !!simple_strtoul(buf, NULL, 0);
 375         int error;
 376
 377         if (!capable(CAP_NET_ADMIN))
 378                 return -EPERM;
 379
 380         if (rfkill->user_claim_unsupported)
 381                 return -EOPNOTSUPP;
 382
 383         /*
 384          * Take the global lock to make sure the kernel is not in
 385          * the middle of rfkill_switch_all
 386          */
 387         error = mutex_lock_interruptible(&rfkill_mutex);
 388         if (error)
 389                 return error;
 390
 391         if (rfkill->user_claim != claim) {
 392                 if (!claim) {
 393                         mutex_lock(&rfkill->mutex);
 394                         rfkill_toggle_radio(rfkill,
 395                                             rfkill_states[rfkill->type],
 396                                             0);
 397                         mutex_unlock(&rfkill->mutex);
 398                 }
 399                 rfkill->user_claim = claim;
 400         }
 401
 402         mutex_unlock(&rfkill_mutex);
 403
 404         return error ? error : count;
 405 }
 406
 407 static struct device_attribute rfkill_dev_attrs[] = {
 408         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 409         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 410         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 411         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 412         __ATTR_NULL
 413 };
 414
 415 static void rfkill_release(struct device *dev)
 416 {
 417         struct rfkill *rfkill = to_rfkill(dev);
 418
 419         kfree(rfkill);
 420         module_put(THIS_MODULE);
 421 }
 422
 423 #ifdef CONFIG_PM
 424 static int rfkill_suspend(struct device *dev, pm_message_t state)
 425 {
 426         struct rfkill *rfkill = to_rfkill(dev);
 427
 428         if (dev->power.power_state.event != state.event) {
 429                 if (state.event & PM_EVENT_SLEEP) {
 430                         /* Stop transmitter, keep state, no notifies */
 431                         update_rfkill_state(rfkill);
 432
 433                         mutex_lock(&rfkill->mutex);
 434                         rfkill->toggle_radio(rfkill->data,
 435                                                 RFKILL_STATE_SOFT_BLOCKED);
 436                         mutex_unlock(&rfkill->mutex);
 437                 }
 438
 439                 dev->power.power_state = state;
 440         }
 441
 442         return 0;
 443 }
 444
 445 static int rfkill_resume(struct device *dev)
 446 {
 447         struct rfkill *rfkill = to_rfkill(dev);
 448
 449         if (dev->power.power_state.event != PM_EVENT_ON) {
 450                 mutex_lock(&rfkill->mutex);
 451
 452                 /* restore radio state AND notify everybody */
 453                 rfkill_toggle_radio(rfkill, rfkill->state, 1);
 454
 455                 mutex_unlock(&rfkill->mutex);
 456         }
 457
 458         dev->power.power_state = PMSG_ON;
 459         return 0;
 460 }
 461 #else
 462 #define rfkill_suspend NULL
 463 #define rfkill_resume NULL
 464 #endif
 465
 466 static int rfkill_blocking_uevent_notifier(struct notifier_block *nb,
 467                                         unsigned long eventid,
 468                                         void *data)
 469 {
 470         struct rfkill *rfkill = (struct rfkill *)data;
 471
 472         switch (eventid) {
 473         case RFKILL_STATE_CHANGED:
 474                 kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 475                 break;
 476         default:
 477                 break;
 478         }
 479
 480         return NOTIFY_DONE;
 481 }
 482
 483 static struct notifier_block rfkill_blocking_uevent_nb = {
 484         .notifier_call  = rfkill_blocking_uevent_notifier,
 485         .priority       = 0,
 486 };
 487
 488 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 489 {
 490         struct rfkill *rfkill = to_rfkill(dev);
 491         int error;
 492
 493         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 494         if (error)
 495                 return error;
 496         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 497                                 rfkill_get_type_str(rfkill->type));
 498         if (error)
 499                 return error;
 500         error = add_uevent_var(env, "RFKILL_STATE=%d", rfkill->state);
 501         return error;
 502 }
 503
 504 static struct class rfkill_class = {
 505         .name           = "rfkill",
 506         .dev_release    = rfkill_release,
 507         .dev_attrs      = rfkill_dev_attrs,
 508         .suspend        = rfkill_suspend,
 509         .resume         = rfkill_resume,
 510         .dev_uevent     = rfkill_dev_uevent,
 511 };
 512
 513 static int rfkill_add_switch(struct rfkill *rfkill)
 514 {
 515         mutex_lock(&rfkill_mutex);
 516
 517         rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0);
 518
 519         list_add_tail(&rfkill->node, &rfkill_list);
 520
 521         mutex_unlock(&rfkill_mutex);
 522
 523         return 0;
 524 }
 525
 526 static void rfkill_remove_switch(struct rfkill *rfkill)
 527 {
 528         mutex_lock(&rfkill_mutex);
 529         list_del_init(&rfkill->node);
 530         mutex_unlock(&rfkill_mutex);
 531
 532         mutex_lock(&rfkill->mutex);
 533         rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1);
 534         mutex_unlock(&rfkill->mutex);
 535 }
 536
 537 /**
 538  * rfkill_allocate - allocate memory for rfkill structure.
 539  * @parent: device that has rf switch on it
 540  * @type: type of the switch (RFKILL_TYPE_*)
 541  *
 542  * This function should be called by the network driver when it needs
 543  * rfkill structure. Once the structure is allocated the driver shoud
 544  * finish its initialization by setting name, private data, enable_radio
 545  * and disable_radio methods and then register it with rfkill_register().
 546  * NOTE: If registration fails the structure shoudl be freed by calling
 547  * rfkill_free() otherwise rfkill_unregister() should be used.
 548  */
 549 struct rfkill *rfkill_allocate(struct device *parent, enum rfkill_type type)
 550 {
 551         struct rfkill *rfkill;
 552         struct device *dev;
 553
 554         rfkill = kzalloc(sizeof(struct rfkill), GFP_KERNEL);
 555         if (!rfkill)
 556                 return NULL;
 557
 558         mutex_init(&rfkill->mutex);
 559         INIT_LIST_HEAD(&rfkill->node);
 560         rfkill->type = type;
 561
 562         dev = &rfkill->dev;
 563         dev->class = &rfkill_class;
 564         dev->parent = parent;
 565         device_initialize(dev);
 566
 567         __module_get(THIS_MODULE);
 568
 569         return rfkill;
 570 }
 571 EXPORT_SYMBOL(rfkill_allocate);
 572
 573 /**
 574  * rfkill_free - Mark rfkill structure for deletion
 575  * @rfkill: rfkill structure to be destroyed
 576  *
 577  * Decrements reference count of rfkill structure so it is destroyed.
 578  * Note that rfkill_free() should _not_ be called after rfkill_unregister().
 579  */
 580 void rfkill_free(struct rfkill *rfkill)
 581 {
 582         if (rfkill)
 583                 put_device(&rfkill->dev);
 584 }
 585 EXPORT_SYMBOL(rfkill_free);
 586
 587 static void rfkill_led_trigger_register(struct rfkill *rfkill)
 588 {
 589 #ifdef CONFIG_RFKILL_LEDS
 590         int error;
 591
 592         rfkill->led_trigger.name = rfkill->dev.bus_id;
 593         error = led_trigger_register(&rfkill->led_trigger);
 594         if (error)
 595                 rfkill->led_trigger.name = NULL;
 596 #endif /* CONFIG_RFKILL_LEDS */
 597 }
 598
 599 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 600 {
 601 #ifdef CONFIG_RFKILL_LEDS
 602         if (rfkill->led_trigger.name) {
 603                 led_trigger_unregister(&rfkill->led_trigger);
 604                 rfkill->led_trigger.name = NULL;
 605         }
 606 #endif
 607 }
 608
 609 /**
 610  * rfkill_register - Register a rfkill structure.
 611  * @rfkill: rfkill structure to be registered
 612  *
 613  * This function should be called by the network driver when the rfkill
 614  * structure needs to be registered. Immediately from registration the
 615  * switch driver should be able to service calls to toggle_radio.
 616  */
 617 int rfkill_register(struct rfkill *rfkill)
 618 {
 619         static atomic_t rfkill_no = ATOMIC_INIT(0);
 620         struct device *dev = &rfkill->dev;
 621         int error;
 622
 623         if (!rfkill->toggle_radio)
 624                 return -EINVAL;
 625         if (rfkill->type >= RFKILL_TYPE_MAX)
 626                 return -EINVAL;
 627
 628         snprintf(dev->bus_id, sizeof(dev->bus_id),
 629                  "rfkill%ld", (long)atomic_inc_return(&rfkill_no) - 1);
 630
 631         rfkill_led_trigger_register(rfkill);
 632
 633         error = rfkill_add_switch(rfkill);
 634         if (error) {
 635                 rfkill_led_trigger_unregister(rfkill);
 636                 return error;
 637         }
 638
 639         error = device_add(dev);
 640         if (error) {
 641                 rfkill_remove_switch(rfkill);
 642                 rfkill_led_trigger_unregister(rfkill);
 643                 return error;
 644         }
 645
 646         return 0;
 647 }
 648 EXPORT_SYMBOL(rfkill_register);
 649
 650 /**
 651  * rfkill_unregister - Unregister a rfkill structure.
 652  * @rfkill: rfkill structure to be unregistered
 653  *
 654  * This function should be called by the network driver during device
 655  * teardown to destroy rfkill structure. Note that rfkill_free() should
 656  * _not_ be called after rfkill_unregister().
 657  */
 658 void rfkill_unregister(struct rfkill *rfkill)
 659 {
 660         device_del(&rfkill->dev);
 661         rfkill_remove_switch(rfkill);
 662         rfkill_led_trigger_unregister(rfkill);
 663         put_device(&rfkill->dev);
 664 }
 665 EXPORT_SYMBOL(rfkill_unregister);
 666
 667 /*
 668  * Rfkill module initialization/deinitialization.
 669  */
 670 static int __init rfkill_init(void)
 671 {
 672         int error;
 673         int i;
 674
 675         /* RFKILL_STATE_HARD_BLOCKED is illegal here... */
 676         if (rfkill_default_state != RFKILL_STATE_SOFT_BLOCKED &&
 677             rfkill_default_state != RFKILL_STATE_UNBLOCKED)
 678                 return -EINVAL;
 679
 680         for (i = 0; i < ARRAY_SIZE(rfkill_states); i++)
 681                 rfkill_states[i] = rfkill_default_state;
 682
 683         error = class_register(&rfkill_class);
 684         if (error) {
 685                 printk(KERN_ERR "rfkill: unable to register rfkill class\n");
 686                 return error;
 687         }
 688
 689         register_rfkill_notifier(&rfkill_blocking_uevent_nb);
 690
 691         return 0;
 692 }
 693
 694 static void __exit rfkill_exit(void)
 695 {
 696         unregister_rfkill_notifier(&rfkill_blocking_uevent_nb);
 697         class_unregister(&rfkill_class);
 698 }
 699
 700 subsys_initcall(rfkill_init);
 701 module_exit(rfkill_exit);