net/rfkill/core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2006 - 2007 Ivo van Doorn
   4  * Copyright (C) 2007 Dmitry Torokhov
   5  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/workqueue.h>
  12 #include <linux/capability.h>
  13 #include <linux/list.h>
  14 #include <linux/mutex.h>
  15 #include <linux/rfkill.h>
  16 #include <linux/sched.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/device.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/wait.h>
  21 #include <linux/poll.h>
  22 #include <linux/fs.h>
  23 #include <linux/slab.h>
  24
  25 #include "rfkill.h"
  26
  27 #define POLL_INTERVAL           (5 * HZ)
  28
  29 #define RFKILL_BLOCK_HW         BIT(0)
  30 #define RFKILL_BLOCK_SW         BIT(1)
  31 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  32 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  33                                  RFKILL_BLOCK_SW |\
  34                                  RFKILL_BLOCK_SW_PREV)
  35 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  36
  37 struct rfkill {
  38         spinlock_t              lock;
  39
  40         enum rfkill_type        type;
  41
  42         unsigned long           state;
  43
  44         u32                     idx;
  45
  46         bool                    registered;
  47         bool                    persistent;
  48         bool                    polling_paused;
  49         bool                    suspended;
  50
  51         const struct rfkill_ops *ops;
  52         void                    *data;
  53
  54 #ifdef CONFIG_RFKILL_LEDS
  55         struct led_trigger      led_trigger;
  56         const char              *ledtrigname;
  57 #endif
  58
  59         struct device           dev;
  60         struct list_head        node;
  61
  62         struct delayed_work     poll_work;
  63         struct work_struct      uevent_work;
  64         struct work_struct      sync_work;
  65         char                    name[];
  66 };
  67 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
  68
  69 struct rfkill_int_event {
  70         struct list_head        list;
  71         struct rfkill_event     ev;
  72 };
  73
  74 struct rfkill_data {
  75         struct list_head        list;
  76         struct list_head        events;
  77         struct mutex            mtx;
  78         wait_queue_head_t       read_wait;
  79         bool                    input_handler;
  80 };
  81
  82
  83 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  84 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  85 MODULE_DESCRIPTION("RF switch support");
  86 MODULE_LICENSE("GPL");
  87
  88
  89 /*
  90  * The locking here should be made much smarter, we currently have
  91  * a bit of a stupid situation because drivers might want to register
  92  * the rfkill struct under their own lock, and take this lock during
  93  * rfkill method calls -- which will cause an AB-BA deadlock situation.
  94  *
  95  * To fix that, we need to rework this code here to be mostly lock-free
  96  * and only use the mutex for list manipulations, not to protect the
  97  * various other global variables. Then we can avoid holding the mutex
  98  * around driver operations, and all is happy.
  99  */
 100 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 101 static DEFINE_MUTEX(rfkill_global_mutex);
 102 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 103
 104 static unsigned int rfkill_default_state = 1;
 105 module_param_named(default_state, rfkill_default_state, uint, 0444);
 106 MODULE_PARM_DESC(default_state,
 107                  "Default initial state for all radio types, 0 = radio off");
 108
 109 static struct {
 110         bool cur, sav;
 111 } rfkill_global_states[NUM_RFKILL_TYPES];
 112
 113 static bool rfkill_epo_lock_active;
 114
 115
 116 #ifdef CONFIG_RFKILL_LEDS
 117 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 118 {
 119         struct led_trigger *trigger;
 120
 121         if (!rfkill->registered)
 122                 return;
 123
 124         trigger = &rfkill->led_trigger;
 125
 126         if (rfkill->state & RFKILL_BLOCK_ANY)
 127                 led_trigger_event(trigger, LED_OFF);
 128         else
 129                 led_trigger_event(trigger, LED_FULL);
 130 }
 131
 132 static int rfkill_led_trigger_activate(struct led_classdev *led)
 133 {
 134         struct rfkill *rfkill;
 135
 136         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 137
 138         rfkill_led_trigger_event(rfkill);
 139
 140         return 0;
 141 }
 142
 143 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 144 {
 145         return rfkill->led_trigger.name;
 146 }
 147 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 148
 149 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 150 {
 151         BUG_ON(!rfkill);
 152
 153         rfkill->ledtrigname = name;
 154 }
 155 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 156
 157 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 158 {
 159         rfkill->led_trigger.name = rfkill->ledtrigname
 160                                         ? : dev_name(&rfkill->dev);
 161         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 162         return led_trigger_register(&rfkill->led_trigger);
 163 }
 164
 165 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 166 {
 167         led_trigger_unregister(&rfkill->led_trigger);
 168 }
 169
 170 static struct led_trigger rfkill_any_led_trigger;
 171 static struct led_trigger rfkill_none_led_trigger;
 172 static struct work_struct rfkill_global_led_trigger_work;
 173
 174 static void rfkill_global_led_trigger_worker(struct work_struct *work)
 175 {
 176         enum led_brightness brightness = LED_OFF;
 177         struct rfkill *rfkill;
 178
 179         mutex_lock(&rfkill_global_mutex);
 180         list_for_each_entry(rfkill, &rfkill_list, node) {
 181                 if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
 182                         brightness = LED_FULL;
 183                         break;
 184                 }
 185         }
 186         mutex_unlock(&rfkill_global_mutex);
 187
 188         led_trigger_event(&rfkill_any_led_trigger, brightness);
 189         led_trigger_event(&rfkill_none_led_trigger,
 190                           brightness == LED_OFF ? LED_FULL : LED_OFF);
 191 }
 192
 193 static void rfkill_global_led_trigger_event(void)
 194 {
 195         schedule_work(&rfkill_global_led_trigger_work);
 196 }
 197
 198 static int rfkill_global_led_trigger_register(void)
 199 {
 200         int ret;
 201
 202         INIT_WORK(&rfkill_global_led_trigger_work,
 203                         rfkill_global_led_trigger_worker);
 204
 205         rfkill_any_led_trigger.name = "rfkill-any";
 206         ret = led_trigger_register(&rfkill_any_led_trigger);
 207         if (ret)
 208                 return ret;
 209
 210         rfkill_none_led_trigger.name = "rfkill-none";
 211         ret = led_trigger_register(&rfkill_none_led_trigger);
 212         if (ret)
 213                 led_trigger_unregister(&rfkill_any_led_trigger);
 214         else
 215                 /* Delay activation until all global triggers are registered */
 216                 rfkill_global_led_trigger_event();
 217
 218         return ret;
 219 }
 220
 221 static void rfkill_global_led_trigger_unregister(void)
 222 {
 223         led_trigger_unregister(&rfkill_none_led_trigger);
 224         led_trigger_unregister(&rfkill_any_led_trigger);
 225         cancel_work_sync(&rfkill_global_led_trigger_work);
 226 }
 227 #else
 228 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 229 {
 230 }
 231
 232 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 233 {
 234         return 0;
 235 }
 236
 237 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 238 {
 239 }
 240
 241 static void rfkill_global_led_trigger_event(void)
 242 {
 243 }
 244
 245 static int rfkill_global_led_trigger_register(void)
 246 {
 247         return 0;
 248 }
 249
 250 static void rfkill_global_led_trigger_unregister(void)
 251 {
 252 }
 253 #endif /* CONFIG_RFKILL_LEDS */
 254
 255 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 256                               enum rfkill_operation op)
 257 {
 258         unsigned long flags;
 259
 260         ev->idx = rfkill->idx;
 261         ev->type = rfkill->type;
 262         ev->op = op;
 263
 264         spin_lock_irqsave(&rfkill->lock, flags);
 265         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 266         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 267                                         RFKILL_BLOCK_SW_PREV));
 268         spin_unlock_irqrestore(&rfkill->lock, flags);
 269 }
 270
 271 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 272 {
 273         struct rfkill_data *data;
 274         struct rfkill_int_event *ev;
 275
 276         list_for_each_entry(data, &rfkill_fds, list) {
 277                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 278                 if (!ev)
 279                         continue;
 280                 rfkill_fill_event(&ev->ev, rfkill, op);
 281                 mutex_lock(&data->mtx);
 282                 list_add_tail(&ev->list, &data->events);
 283                 mutex_unlock(&data->mtx);
 284                 wake_up_interruptible(&data->read_wait);
 285         }
 286 }
 287
 288 static void rfkill_event(struct rfkill *rfkill)
 289 {
 290         if (!rfkill->registered)
 291                 return;
 292
 293         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 294
 295         /* also send event to /dev/rfkill */
 296         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 297 }
 298
 299 /**
 300  * rfkill_set_block - wrapper for set_block method
 301  *
 302  * @rfkill: the rfkill struct to use
 303  * @blocked: the new software state
 304  *
 305  * Calls the set_block method (when applicable) and handles notifications
 306  * etc. as well.
 307  */
 308 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 309 {
 310         unsigned long flags;
 311         bool prev, curr;
 312         int err;
 313
 314         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 315                 return;
 316
 317         /*
 318          * Some platforms (...!) generate input events which affect the
 319          * _hard_ kill state -- whenever something tries to change the
 320          * current software state query the hardware state too.
 321          */
 322         if (rfkill->ops->query)
 323                 rfkill->ops->query(rfkill, rfkill->data);
 324
 325         spin_lock_irqsave(&rfkill->lock, flags);
 326         prev = rfkill->state & RFKILL_BLOCK_SW;
 327
 328         if (prev)
 329                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 330         else
 331                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 332
 333         if (blocked)
 334                 rfkill->state |= RFKILL_BLOCK_SW;
 335         else
 336                 rfkill->state &= ~RFKILL_BLOCK_SW;
 337
 338         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 339         spin_unlock_irqrestore(&rfkill->lock, flags);
 340
 341         err = rfkill->ops->set_block(rfkill->data, blocked);
 342
 343         spin_lock_irqsave(&rfkill->lock, flags);
 344         if (err) {
 345                 /*
 346                  * Failed -- reset status to _PREV, which may be different
 347                  * from what we have set _PREV to earlier in this function
 348                  * if rfkill_set_sw_state was invoked.
 349                  */
 350                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 351                         rfkill->state |= RFKILL_BLOCK_SW;
 352                 else
 353                         rfkill->state &= ~RFKILL_BLOCK_SW;
 354         }
 355         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 356         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 357         curr = rfkill->state & RFKILL_BLOCK_SW;
 358         spin_unlock_irqrestore(&rfkill->lock, flags);
 359
 360         rfkill_led_trigger_event(rfkill);
 361         rfkill_global_led_trigger_event();
 362
 363         if (prev != curr)
 364                 rfkill_event(rfkill);
 365 }
 366
 367 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
 368 {
 369         int i;
 370
 371         if (type != RFKILL_TYPE_ALL) {
 372                 rfkill_global_states[type].cur = blocked;
 373                 return;
 374         }
 375
 376         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 377                 rfkill_global_states[i].cur = blocked;
 378 }
 379
 380 #ifdef CONFIG_RFKILL_INPUT
 381 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 382
 383 /**
 384  * __rfkill_switch_all - Toggle state of all switches of given type
 385  * @type: type of interfaces to be affected
 386  * @blocked: the new state
 387  *
 388  * This function sets the state of all switches of given type,
 389  * unless a specific switch is suspended.
 390  *
 391  * Caller must have acquired rfkill_global_mutex.
 392  */
 393 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 394 {
 395         struct rfkill *rfkill;
 396
 397         rfkill_update_global_state(type, blocked);
 398         list_for_each_entry(rfkill, &rfkill_list, node) {
 399                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 400                         continue;
 401
 402                 rfkill_set_block(rfkill, blocked);
 403         }
 404 }
 405
 406 /**
 407  * rfkill_switch_all - Toggle state of all switches of given type
 408  * @type: type of interfaces to be affected
 409  * @blocked: the new state
 410  *
 411  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 412  * Please refer to __rfkill_switch_all() for details.
 413  *
 414  * Does nothing if the EPO lock is active.
 415  */
 416 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 417 {
 418         if (atomic_read(&rfkill_input_disabled))
 419                 return;
 420
 421         mutex_lock(&rfkill_global_mutex);
 422
 423         if (!rfkill_epo_lock_active)
 424                 __rfkill_switch_all(type, blocked);
 425
 426         mutex_unlock(&rfkill_global_mutex);
 427 }
 428
 429 /**
 430  * rfkill_epo - emergency power off all transmitters
 431  *
 432  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 433  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 434  *
 435  * The global state before the EPO is saved and can be restored later
 436  * using rfkill_restore_states().
 437  */
 438 void rfkill_epo(void)
 439 {
 440         struct rfkill *rfkill;
 441         int i;
 442
 443         if (atomic_read(&rfkill_input_disabled))
 444                 return;
 445
 446         mutex_lock(&rfkill_global_mutex);
 447
 448         rfkill_epo_lock_active = true;
 449         list_for_each_entry(rfkill, &rfkill_list, node)
 450                 rfkill_set_block(rfkill, true);
 451
 452         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 453                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 454                 rfkill_global_states[i].cur = true;
 455         }
 456
 457         mutex_unlock(&rfkill_global_mutex);
 458 }
 459
 460 /**
 461  * rfkill_restore_states - restore global states
 462  *
 463  * Restore (and sync switches to) the global state from the
 464  * states in rfkill_default_states.  This can undo the effects of
 465  * a call to rfkill_epo().
 466  */
 467 void rfkill_restore_states(void)
 468 {
 469         int i;
 470
 471         if (atomic_read(&rfkill_input_disabled))
 472                 return;
 473
 474         mutex_lock(&rfkill_global_mutex);
 475
 476         rfkill_epo_lock_active = false;
 477         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 478                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 479         mutex_unlock(&rfkill_global_mutex);
 480 }
 481
 482 /**
 483  * rfkill_remove_epo_lock - unlock state changes
 484  *
 485  * Used by rfkill-input manually unlock state changes, when
 486  * the EPO switch is deactivated.
 487  */
 488 void rfkill_remove_epo_lock(void)
 489 {
 490         if (atomic_read(&rfkill_input_disabled))
 491                 return;
 492
 493         mutex_lock(&rfkill_global_mutex);
 494         rfkill_epo_lock_active = false;
 495         mutex_unlock(&rfkill_global_mutex);
 496 }
 497
 498 /**
 499  * rfkill_is_epo_lock_active - returns true EPO is active
 500  *
 501  * Returns 0 (false) if there is NOT an active EPO condition,
 502  * and 1 (true) if there is an active EPO condition, which
 503  * locks all radios in one of the BLOCKED states.
 504  *
 505  * Can be called in atomic context.
 506  */
 507 bool rfkill_is_epo_lock_active(void)
 508 {
 509         return rfkill_epo_lock_active;
 510 }
 511
 512 /**
 513  * rfkill_get_global_sw_state - returns global state for a type
 514  * @type: the type to get the global state of
 515  *
 516  * Returns the current global state for a given wireless
 517  * device type.
 518  */
 519 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 520 {
 521         return rfkill_global_states[type].cur;
 522 }
 523 #endif
 524
 525 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 526 {
 527         unsigned long flags;
 528         bool ret, prev;
 529
 530         BUG_ON(!rfkill);
 531
 532         spin_lock_irqsave(&rfkill->lock, flags);
 533         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 534         if (blocked)
 535                 rfkill->state |= RFKILL_BLOCK_HW;
 536         else
 537                 rfkill->state &= ~RFKILL_BLOCK_HW;
 538         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
 539         spin_unlock_irqrestore(&rfkill->lock, flags);
 540
 541         rfkill_led_trigger_event(rfkill);
 542         rfkill_global_led_trigger_event();
 543
 544         if (rfkill->registered && prev != blocked)
 545                 schedule_work(&rfkill->uevent_work);
 546
 547         return ret;
 548 }
 549 EXPORT_SYMBOL(rfkill_set_hw_state);
 550
 551 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 552 {
 553         u32 bit = RFKILL_BLOCK_SW;
 554
 555         /* if in a ops->set_block right now, use other bit */
 556         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 557                 bit = RFKILL_BLOCK_SW_PREV;
 558
 559         if (blocked)
 560                 rfkill->state |= bit;
 561         else
 562                 rfkill->state &= ~bit;
 563 }
 564
 565 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 566 {
 567         unsigned long flags;
 568         bool prev, hwblock;
 569
 570         BUG_ON(!rfkill);
 571
 572         spin_lock_irqsave(&rfkill->lock, flags);
 573         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 574         __rfkill_set_sw_state(rfkill, blocked);
 575         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 576         blocked = blocked || hwblock;
 577         spin_unlock_irqrestore(&rfkill->lock, flags);
 578
 579         if (!rfkill->registered)
 580                 return blocked;
 581
 582         if (prev != blocked && !hwblock)
 583                 schedule_work(&rfkill->uevent_work);
 584
 585         rfkill_led_trigger_event(rfkill);
 586         rfkill_global_led_trigger_event();
 587
 588         return blocked;
 589 }
 590 EXPORT_SYMBOL(rfkill_set_sw_state);
 591
 592 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 593 {
 594         unsigned long flags;
 595
 596         BUG_ON(!rfkill);
 597         BUG_ON(rfkill->registered);
 598
 599         spin_lock_irqsave(&rfkill->lock, flags);
 600         __rfkill_set_sw_state(rfkill, blocked);
 601         rfkill->persistent = true;
 602         spin_unlock_irqrestore(&rfkill->lock, flags);
 603 }
 604 EXPORT_SYMBOL(rfkill_init_sw_state);
 605
 606 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 607 {
 608         unsigned long flags;
 609         bool swprev, hwprev;
 610
 611         BUG_ON(!rfkill);
 612
 613         spin_lock_irqsave(&rfkill->lock, flags);
 614
 615         /*
 616          * No need to care about prev/setblock ... this is for uevent only
 617          * and that will get triggered by rfkill_set_block anyway.
 618          */
 619         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 620         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 621         __rfkill_set_sw_state(rfkill, sw);
 622         if (hw)
 623                 rfkill->state |= RFKILL_BLOCK_HW;
 624         else
 625                 rfkill->state &= ~RFKILL_BLOCK_HW;
 626
 627         spin_unlock_irqrestore(&rfkill->lock, flags);
 628
 629         if (!rfkill->registered) {
 630                 rfkill->persistent = true;
 631         } else {
 632                 if (swprev != sw || hwprev != hw)
 633                         schedule_work(&rfkill->uevent_work);
 634
 635                 rfkill_led_trigger_event(rfkill);
 636                 rfkill_global_led_trigger_event();
 637         }
 638 }
 639 EXPORT_SYMBOL(rfkill_set_states);
 640
 641 static const char * const rfkill_types[] = {
 642         NULL, /* RFKILL_TYPE_ALL */
 643         "wlan",
 644         "bluetooth",
 645         "ultrawideband",
 646         "wimax",
 647         "wwan",
 648         "gps",
 649         "fm",
 650         "nfc",
 651 };
 652
 653 enum rfkill_type rfkill_find_type(const char *name)
 654 {
 655         int i;
 656
 657         BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
 658
 659         if (!name)
 660                 return RFKILL_TYPE_ALL;
 661
 662         for (i = 1; i < NUM_RFKILL_TYPES; i++)
 663                 if (!strcmp(name, rfkill_types[i]))
 664                         return i;
 665         return RFKILL_TYPE_ALL;
 666 }
 667 EXPORT_SYMBOL(rfkill_find_type);
 668
 669 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 670                          char *buf)
 671 {
 672         struct rfkill *rfkill = to_rfkill(dev);
 673
 674         return sprintf(buf, "%s\n", rfkill->name);
 675 }
 676 static DEVICE_ATTR_RO(name);
 677
 678 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 679                          char *buf)
 680 {
 681         struct rfkill *rfkill = to_rfkill(dev);
 682
 683         return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
 684 }
 685 static DEVICE_ATTR_RO(type);
 686
 687 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 688                           char *buf)
 689 {
 690         struct rfkill *rfkill = to_rfkill(dev);
 691
 692         return sprintf(buf, "%d\n", rfkill->idx);
 693 }
 694 static DEVICE_ATTR_RO(index);
 695
 696 static ssize_t persistent_show(struct device *dev,
 697                                struct device_attribute *attr, char *buf)
 698 {
 699         struct rfkill *rfkill = to_rfkill(dev);
 700
 701         return sprintf(buf, "%d\n", rfkill->persistent);
 702 }
 703 static DEVICE_ATTR_RO(persistent);
 704
 705 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 706                          char *buf)
 707 {
 708         struct rfkill *rfkill = to_rfkill(dev);
 709
 710         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 711 }
 712 static DEVICE_ATTR_RO(hard);
 713
 714 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 715                          char *buf)
 716 {
 717         struct rfkill *rfkill = to_rfkill(dev);
 718
 719         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 720 }
 721
 722 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 723                           const char *buf, size_t count)
 724 {
 725         struct rfkill *rfkill = to_rfkill(dev);
 726         unsigned long state;
 727         int err;
 728
 729         if (!capable(CAP_NET_ADMIN))
 730                 return -EPERM;
 731
 732         err = kstrtoul(buf, 0, &state);
 733         if (err)
 734                 return err;
 735
 736         if (state > 1 )
 737                 return -EINVAL;
 738
 739         mutex_lock(&rfkill_global_mutex);
 740         rfkill_set_block(rfkill, state);
 741         mutex_unlock(&rfkill_global_mutex);
 742
 743         return count;
 744 }
 745 static DEVICE_ATTR_RW(soft);
 746
 747 static u8 user_state_from_blocked(unsigned long state)
 748 {
 749         if (state & RFKILL_BLOCK_HW)
 750                 return RFKILL_USER_STATE_HARD_BLOCKED;
 751         if (state & RFKILL_BLOCK_SW)
 752                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 753
 754         return RFKILL_USER_STATE_UNBLOCKED;
 755 }
 756
 757 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 758                           char *buf)
 759 {
 760         struct rfkill *rfkill = to_rfkill(dev);
 761
 762         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 763 }
 764
 765 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 766                            const char *buf, size_t count)
 767 {
 768         struct rfkill *rfkill = to_rfkill(dev);
 769         unsigned long state;
 770         int err;
 771
 772         if (!capable(CAP_NET_ADMIN))
 773                 return -EPERM;
 774
 775         err = kstrtoul(buf, 0, &state);
 776         if (err)
 777                 return err;
 778
 779         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 780             state != RFKILL_USER_STATE_UNBLOCKED)
 781                 return -EINVAL;
 782
 783         mutex_lock(&rfkill_global_mutex);
 784         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 785         mutex_unlock(&rfkill_global_mutex);
 786
 787         return count;
 788 }
 789 static DEVICE_ATTR_RW(state);
 790
 791 static struct attribute *rfkill_dev_attrs[] = {
 792         &dev_attr_name.attr,
 793         &dev_attr_type.attr,
 794         &dev_attr_index.attr,
 795         &dev_attr_persistent.attr,
 796         &dev_attr_state.attr,
 797         &dev_attr_soft.attr,
 798         &dev_attr_hard.attr,
 799         NULL,
 800 };
 801 ATTRIBUTE_GROUPS(rfkill_dev);
 802
 803 static void rfkill_release(struct device *dev)
 804 {
 805         struct rfkill *rfkill = to_rfkill(dev);
 806
 807         kfree(rfkill);
 808 }
 809
 810 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 811 {
 812         struct rfkill *rfkill = to_rfkill(dev);
 813         unsigned long flags;
 814         u32 state;
 815         int error;
 816
 817         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 818         if (error)
 819                 return error;
 820         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 821                                rfkill_types[rfkill->type]);
 822         if (error)
 823                 return error;
 824         spin_lock_irqsave(&rfkill->lock, flags);
 825         state = rfkill->state;
 826         spin_unlock_irqrestore(&rfkill->lock, flags);
 827         error = add_uevent_var(env, "RFKILL_STATE=%d",
 828                                user_state_from_blocked(state));
 829         return error;
 830 }
 831
 832 void rfkill_pause_polling(struct rfkill *rfkill)
 833 {
 834         BUG_ON(!rfkill);
 835
 836         if (!rfkill->ops->poll)
 837                 return;
 838
 839         rfkill->polling_paused = true;
 840         cancel_delayed_work_sync(&rfkill->poll_work);
 841 }
 842 EXPORT_SYMBOL(rfkill_pause_polling);
 843
 844 void rfkill_resume_polling(struct rfkill *rfkill)
 845 {
 846         BUG_ON(!rfkill);
 847
 848         if (!rfkill->ops->poll)
 849                 return;
 850
 851         rfkill->polling_paused = false;
 852
 853         if (rfkill->suspended)
 854                 return;
 855
 856         queue_delayed_work(system_power_efficient_wq,
 857                            &rfkill->poll_work, 0);
 858 }
 859 EXPORT_SYMBOL(rfkill_resume_polling);
 860
 861 #ifdef CONFIG_PM_SLEEP
 862 static int rfkill_suspend(struct device *dev)
 863 {
 864         struct rfkill *rfkill = to_rfkill(dev);
 865
 866         rfkill->suspended = true;
 867         cancel_delayed_work_sync(&rfkill->poll_work);
 868
 869         return 0;
 870 }
 871
 872 static int rfkill_resume(struct device *dev)
 873 {
 874         struct rfkill *rfkill = to_rfkill(dev);
 875         bool cur;
 876
 877         rfkill->suspended = false;
 878
 879         if (!rfkill->registered)
 880                 return 0;
 881
 882         if (!rfkill->persistent) {
 883                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 884                 rfkill_set_block(rfkill, cur);
 885         }
 886
 887         if (rfkill->ops->poll && !rfkill->polling_paused)
 888                 queue_delayed_work(system_power_efficient_wq,
 889                                    &rfkill->poll_work, 0);
 890
 891         return 0;
 892 }
 893
 894 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 895 #define RFKILL_PM_OPS (&rfkill_pm_ops)
 896 #else
 897 #define RFKILL_PM_OPS NULL
 898 #endif
 899
 900 static struct class rfkill_class = {
 901         .name           = "rfkill",
 902         .dev_release    = rfkill_release,
 903         .dev_groups     = rfkill_dev_groups,
 904         .dev_uevent     = rfkill_dev_uevent,
 905         .pm             = RFKILL_PM_OPS,
 906 };
 907
 908 bool rfkill_blocked(struct rfkill *rfkill)
 909 {
 910         unsigned long flags;
 911         u32 state;
 912
 913         spin_lock_irqsave(&rfkill->lock, flags);
 914         state = rfkill->state;
 915         spin_unlock_irqrestore(&rfkill->lock, flags);
 916
 917         return !!(state & RFKILL_BLOCK_ANY);
 918 }
 919 EXPORT_SYMBOL(rfkill_blocked);
 920
 921
 922 struct rfkill * __must_check rfkill_alloc(const char *name,
 923                                           struct device *parent,
 924                                           const enum rfkill_type type,
 925                                           const struct rfkill_ops *ops,
 926                                           void *ops_data)
 927 {
 928         struct rfkill *rfkill;
 929         struct device *dev;
 930
 931         if (WARN_ON(!ops))
 932                 return NULL;
 933
 934         if (WARN_ON(!ops->set_block))
 935                 return NULL;
 936
 937         if (WARN_ON(!name))
 938                 return NULL;
 939
 940         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 941                 return NULL;
 942
 943         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 944         if (!rfkill)
 945                 return NULL;
 946
 947         spin_lock_init(&rfkill->lock);
 948         INIT_LIST_HEAD(&rfkill->node);
 949         rfkill->type = type;
 950         strcpy(rfkill->name, name);
 951         rfkill->ops = ops;
 952         rfkill->data = ops_data;
 953
 954         dev = &rfkill->dev;
 955         dev->class = &rfkill_class;
 956         dev->parent = parent;
 957         device_initialize(dev);
 958
 959         return rfkill;
 960 }
 961 EXPORT_SYMBOL(rfkill_alloc);
 962
 963 static void rfkill_poll(struct work_struct *work)
 964 {
 965         struct rfkill *rfkill;
 966
 967         rfkill = container_of(work, struct rfkill, poll_work.work);
 968
 969         /*
 970          * Poll hardware state -- driver will use one of the
 971          * rfkill_set{,_hw,_sw}_state functions and use its
 972          * return value to update the current status.
 973          */
 974         rfkill->ops->poll(rfkill, rfkill->data);
 975
 976         queue_delayed_work(system_power_efficient_wq,
 977                 &rfkill->poll_work,
 978                 round_jiffies_relative(POLL_INTERVAL));
 979 }
 980
 981 static void rfkill_uevent_work(struct work_struct *work)
 982 {
 983         struct rfkill *rfkill;
 984
 985         rfkill = container_of(work, struct rfkill, uevent_work);
 986
 987         mutex_lock(&rfkill_global_mutex);
 988         rfkill_event(rfkill);
 989         mutex_unlock(&rfkill_global_mutex);
 990 }
 991
 992 static void rfkill_sync_work(struct work_struct *work)
 993 {
 994         struct rfkill *rfkill;
 995         bool cur;
 996
 997         rfkill = container_of(work, struct rfkill, sync_work);
 998
 999         mutex_lock(&rfkill_global_mutex);
1000         cur = rfkill_global_states[rfkill->type].cur;
1001         rfkill_set_block(rfkill, cur);
1002         mutex_unlock(&rfkill_global_mutex);
1003 }
1004
1005 int __must_check rfkill_register(struct rfkill *rfkill)
1006 {
1007         static unsigned long rfkill_no;
1008         struct device *dev;
1009         int error;
1010
1011         if (!rfkill)
1012                 return -EINVAL;
1013
1014         dev = &rfkill->dev;
1015
1016         mutex_lock(&rfkill_global_mutex);
1017
1018         if (rfkill->registered) {
1019                 error = -EALREADY;
1020                 goto unlock;
1021         }
1022
1023         rfkill->idx = rfkill_no;
1024         dev_set_name(dev, "rfkill%lu", rfkill_no);
1025         rfkill_no++;
1026
1027         list_add_tail(&rfkill->node, &rfkill_list);
1028
1029         error = device_add(dev);
1030         if (error)
1031                 goto remove;
1032
1033         error = rfkill_led_trigger_register(rfkill);
1034         if (error)
1035                 goto devdel;
1036
1037         rfkill->registered = true;
1038
1039         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
1040         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
1041         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
1042
1043         if (rfkill->ops->poll)
1044                 queue_delayed_work(system_power_efficient_wq,
1045                         &rfkill->poll_work,
1046                         round_jiffies_relative(POLL_INTERVAL));
1047
1048         if (!rfkill->persistent || rfkill_epo_lock_active) {
1049                 schedule_work(&rfkill->sync_work);
1050         } else {
1051 #ifdef CONFIG_RFKILL_INPUT
1052                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
1053
1054                 if (!atomic_read(&rfkill_input_disabled))
1055                         __rfkill_switch_all(rfkill->type, soft_blocked);
1056 #endif
1057         }
1058
1059         rfkill_global_led_trigger_event();
1060         rfkill_send_events(rfkill, RFKILL_OP_ADD);
1061
1062         mutex_unlock(&rfkill_global_mutex);
1063         return 0;
1064
1065  devdel:
1066         device_del(&rfkill->dev);
1067  remove:
1068         list_del_init(&rfkill->node);
1069  unlock:
1070         mutex_unlock(&rfkill_global_mutex);
1071         return error;
1072 }
1073 EXPORT_SYMBOL(rfkill_register);
1074
1075 void rfkill_unregister(struct rfkill *rfkill)
1076 {
1077         BUG_ON(!rfkill);
1078
1079         if (rfkill->ops->poll)
1080                 cancel_delayed_work_sync(&rfkill->poll_work);
1081
1082         cancel_work_sync(&rfkill->uevent_work);
1083         cancel_work_sync(&rfkill->sync_work);
1084
1085         rfkill->registered = false;
1086
1087         device_del(&rfkill->dev);
1088
1089         mutex_lock(&rfkill_global_mutex);
1090         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1091         list_del_init(&rfkill->node);
1092         rfkill_global_led_trigger_event();
1093         mutex_unlock(&rfkill_global_mutex);
1094
1095         rfkill_led_trigger_unregister(rfkill);
1096 }
1097 EXPORT_SYMBOL(rfkill_unregister);
1098
1099 void rfkill_destroy(struct rfkill *rfkill)
1100 {
1101         if (rfkill)
1102                 put_device(&rfkill->dev);
1103 }
1104 EXPORT_SYMBOL(rfkill_destroy);
1105
1106 static int rfkill_fop_open(struct inode *inode, struct file *file)
1107 {
1108         struct rfkill_data *data;
1109         struct rfkill *rfkill;
1110         struct rfkill_int_event *ev, *tmp;
1111
1112         data = kzalloc(sizeof(*data), GFP_KERNEL);
1113         if (!data)
1114                 return -ENOMEM;
1115
1116         INIT_LIST_HEAD(&data->events);
1117         mutex_init(&data->mtx);
1118         init_waitqueue_head(&data->read_wait);
1119
1120         mutex_lock(&rfkill_global_mutex);
1121         mutex_lock(&data->mtx);
1122         /*
1123          * start getting events from elsewhere but hold mtx to get
1124          * startup events added first
1125          */
1126
1127         list_for_each_entry(rfkill, &rfkill_list, node) {
1128                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1129                 if (!ev)
1130                         goto free;
1131                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1132                 list_add_tail(&ev->list, &data->events);
1133         }
1134         list_add(&data->list, &rfkill_fds);
1135         mutex_unlock(&data->mtx);
1136         mutex_unlock(&rfkill_global_mutex);
1137
1138         file->private_data = data;
1139
1140         return stream_open(inode, file);
1141
1142  free:
1143         mutex_unlock(&data->mtx);
1144         mutex_unlock(&rfkill_global_mutex);
1145         mutex_destroy(&data->mtx);
1146         list_for_each_entry_safe(ev, tmp, &data->events, list)
1147                 kfree(ev);
1148         kfree(data);
1149         return -ENOMEM;
1150 }
1151
1152 static __poll_t rfkill_fop_poll(struct file *file, poll_table *wait)
1153 {
1154         struct rfkill_data *data = file->private_data;
1155         __poll_t res = EPOLLOUT | EPOLLWRNORM;
1156
1157         poll_wait(file, &data->read_wait, wait);
1158
1159         mutex_lock(&data->mtx);
1160         if (!list_empty(&data->events))
1161                 res = EPOLLIN | EPOLLRDNORM;
1162         mutex_unlock(&data->mtx);
1163
1164         return res;
1165 }
1166
1167 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1168                                size_t count, loff_t *pos)
1169 {
1170         struct rfkill_data *data = file->private_data;
1171         struct rfkill_int_event *ev;
1172         unsigned long sz;
1173         int ret;
1174
1175         mutex_lock(&data->mtx);
1176
1177         while (list_empty(&data->events)) {
1178                 if (file->f_flags & O_NONBLOCK) {
1179                         ret = -EAGAIN;
1180                         goto out;
1181                 }
1182                 mutex_unlock(&data->mtx);
1183                 /* since we re-check and it just compares pointers,
1184                  * using !list_empty() without locking isn't a problem
1185                  */
1186                 ret = wait_event_interruptible(data->read_wait,
1187                                                !list_empty(&data->events));
1188                 mutex_lock(&data->mtx);
1189
1190                 if (ret)
1191                         goto out;
1192         }
1193
1194         ev = list_first_entry(&data->events, struct rfkill_int_event,
1195                                 list);
1196
1197         sz = min_t(unsigned long, sizeof(ev->ev), count);
1198         ret = sz;
1199         if (copy_to_user(buf, &ev->ev, sz))
1200                 ret = -EFAULT;
1201
1202         list_del(&ev->list);
1203         kfree(ev);
1204  out:
1205         mutex_unlock(&data->mtx);
1206         return ret;
1207 }
1208
1209 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1210                                 size_t count, loff_t *pos)
1211 {
1212         struct rfkill *rfkill;
1213         struct rfkill_event ev;
1214         int ret;
1215
1216         /* we don't need the 'hard' variable but accept it */
1217         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1218                 return -EINVAL;
1219
1220         /*
1221          * Copy as much data as we can accept into our 'ev' buffer,
1222          * but tell userspace how much we've copied so it can determine
1223          * our API version even in a write() call, if it cares.
1224          */
1225         count = min(count, sizeof(ev));
1226         if (copy_from_user(&ev, buf, count))
1227                 return -EFAULT;
1228
1229         if (ev.type >= NUM_RFKILL_TYPES)
1230                 return -EINVAL;
1231
1232         mutex_lock(&rfkill_global_mutex);
1233
1234         switch (ev.op) {
1235         case RFKILL_OP_CHANGE_ALL:
1236                 rfkill_update_global_state(ev.type, ev.soft);
1237                 list_for_each_entry(rfkill, &rfkill_list, node)
1238                         if (rfkill->type == ev.type ||
1239                             ev.type == RFKILL_TYPE_ALL)
1240                                 rfkill_set_block(rfkill, ev.soft);
1241                 ret = 0;
1242                 break;
1243         case RFKILL_OP_CHANGE:
1244                 list_for_each_entry(rfkill, &rfkill_list, node)
1245                         if (rfkill->idx == ev.idx &&
1246                             (rfkill->type == ev.type ||
1247                              ev.type == RFKILL_TYPE_ALL))
1248                                 rfkill_set_block(rfkill, ev.soft);
1249                 ret = 0;
1250                 break;
1251         default:
1252                 ret = -EINVAL;
1253                 break;
1254         }
1255
1256         mutex_unlock(&rfkill_global_mutex);
1257
1258         return ret ?: count;
1259 }
1260
1261 static int rfkill_fop_release(struct inode *inode, struct file *file)
1262 {
1263         struct rfkill_data *data = file->private_data;
1264         struct rfkill_int_event *ev, *tmp;
1265
1266         mutex_lock(&rfkill_global_mutex);
1267         list_del(&data->list);
1268         mutex_unlock(&rfkill_global_mutex);
1269
1270         mutex_destroy(&data->mtx);
1271         list_for_each_entry_safe(ev, tmp, &data->events, list)
1272                 kfree(ev);
1273
1274 #ifdef CONFIG_RFKILL_INPUT
1275         if (data->input_handler)
1276                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1277                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1278 #endif
1279
1280         kfree(data);
1281
1282         return 0;
1283 }
1284
1285 #ifdef CONFIG_RFKILL_INPUT
1286 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1287                              unsigned long arg)
1288 {
1289         struct rfkill_data *data = file->private_data;
1290
1291         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1292                 return -ENOSYS;
1293
1294         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1295                 return -ENOSYS;
1296
1297         mutex_lock(&data->mtx);
1298
1299         if (!data->input_handler) {
1300                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1301                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1302                 data->input_handler = true;
1303         }
1304
1305         mutex_unlock(&data->mtx);
1306
1307         return 0;
1308 }
1309 #endif
1310
1311 static const struct file_operations rfkill_fops = {
1312         .owner          = THIS_MODULE,
1313         .open           = rfkill_fop_open,
1314         .read           = rfkill_fop_read,
1315         .write          = rfkill_fop_write,
1316         .poll           = rfkill_fop_poll,
1317         .release        = rfkill_fop_release,
1318 #ifdef CONFIG_RFKILL_INPUT
1319         .unlocked_ioctl = rfkill_fop_ioctl,
1320         .compat_ioctl   = rfkill_fop_ioctl,
1321 #endif
1322         .llseek         = no_llseek,
1323 };
1324
1325 #define RFKILL_NAME "rfkill"
1326
1327 static struct miscdevice rfkill_miscdev = {
1328         .fops   = &rfkill_fops,
1329         .name   = RFKILL_NAME,
1330         .minor  = RFKILL_MINOR,
1331 };
1332
1333 static int __init rfkill_init(void)
1334 {
1335         int error;
1336
1337         rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1338
1339         error = class_register(&rfkill_class);
1340         if (error)
1341                 goto error_class;
1342
1343         error = misc_register(&rfkill_miscdev);
1344         if (error)
1345                 goto error_misc;
1346
1347         error = rfkill_global_led_trigger_register();
1348         if (error)
1349                 goto error_led_trigger;
1350
1351 #ifdef CONFIG_RFKILL_INPUT
1352         error = rfkill_handler_init();
1353         if (error)
1354                 goto error_input;
1355 #endif
1356
1357         return 0;
1358
1359 #ifdef CONFIG_RFKILL_INPUT
1360 error_input:
1361         rfkill_global_led_trigger_unregister();
1362 #endif
1363 error_led_trigger:
1364         misc_deregister(&rfkill_miscdev);
1365 error_misc:
1366         class_unregister(&rfkill_class);
1367 error_class:
1368         return error;
1369 }
1370 subsys_initcall(rfkill_init);
1371
1372 static void __exit rfkill_exit(void)
1373 {
1374 #ifdef CONFIG_RFKILL_INPUT
1375         rfkill_handler_exit();
1376 #endif
1377         rfkill_global_led_trigger_unregister();
1378         misc_deregister(&rfkill_miscdev);
1379         class_unregister(&rfkill_class);
1380 }
1381 module_exit(rfkill_exit);
1382
1383 MODULE_ALIAS_MISCDEV(RFKILL_MINOR);
1384 MODULE_ALIAS("devname:" RFKILL_NAME);