net/rfkill/core.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the
  18  * Free Software Foundation, Inc.,
  19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/capability.h>
  27 #include <linux/list.h>
  28 #include <linux/mutex.h>
  29 #include <linux/rfkill.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/miscdevice.h>
  32 #include <linux/wait.h>
  33 #include <linux/poll.h>
  34 #include <linux/fs.h>
  35
  36 #include "rfkill.h"
  37
  38 #define POLL_INTERVAL           (5 * HZ)
  39
  40 #define RFKILL_BLOCK_HW         BIT(0)
  41 #define RFKILL_BLOCK_SW         BIT(1)
  42 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  43 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  44                                  RFKILL_BLOCK_SW |\
  45                                  RFKILL_BLOCK_SW_PREV)
  46 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  47
  48 struct rfkill {
  49         spinlock_t              lock;
  50
  51         const char              *name;
  52         enum rfkill_type        type;
  53
  54         unsigned long           state;
  55
  56         u32                     idx;
  57
  58         bool                    registered;
  59         bool                    suspended;
  60
  61         const struct rfkill_ops *ops;
  62         void                    *data;
  63
  64 #ifdef CONFIG_RFKILL_LEDS
  65         struct led_trigger      led_trigger;
  66         const char              *ledtrigname;
  67 #endif
  68
  69         struct device           dev;
  70         struct list_head        node;
  71
  72         struct delayed_work     poll_work;
  73         struct work_struct      uevent_work;
  74         struct work_struct      sync_work;
  75 };
  76 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
  77
  78 struct rfkill_int_event {
  79         struct list_head        list;
  80         struct rfkill_event     ev;
  81 };
  82
  83 struct rfkill_data {
  84         struct list_head        list;
  85         struct list_head        events;
  86         struct mutex            mtx;
  87         wait_queue_head_t       read_wait;
  88         bool                    input_handler;
  89 };
  90
  91
  92 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  93 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  94 MODULE_DESCRIPTION("RF switch support");
  95 MODULE_LICENSE("GPL");
  96
  97
  98 /*
  99  * The locking here should be made much smarter, we currently have
 100  * a bit of a stupid situation because drivers might want to register
 101  * the rfkill struct under their own lock, and take this lock during
 102  * rfkill method calls -- which will cause an AB-BA deadlock situation.
 103  *
 104  * To fix that, we need to rework this code here to be mostly lock-free
 105  * and only use the mutex for list manipulations, not to protect the
 106  * various other global variables. Then we can avoid holding the mutex
 107  * around driver operations, and all is happy.
 108  */
 109 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 110 static DEFINE_MUTEX(rfkill_global_mutex);
 111 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 112
 113 static unsigned int rfkill_default_state = 1;
 114 module_param_named(default_state, rfkill_default_state, uint, 0444);
 115 MODULE_PARM_DESC(default_state,
 116                  "Default initial state for all radio types, 0 = radio off");
 117
 118 static struct {
 119         bool cur, def;
 120 } rfkill_global_states[NUM_RFKILL_TYPES];
 121
 122 static unsigned long rfkill_states_default_locked;
 123
 124 static bool rfkill_epo_lock_active;
 125
 126
 127 #ifdef CONFIG_RFKILL_LEDS
 128 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 129 {
 130         struct led_trigger *trigger;
 131
 132         if (!rfkill->registered)
 133                 return;
 134
 135         trigger = &rfkill->led_trigger;
 136
 137         if (rfkill->state & RFKILL_BLOCK_ANY)
 138                 led_trigger_event(trigger, LED_OFF);
 139         else
 140                 led_trigger_event(trigger, LED_FULL);
 141 }
 142
 143 static void rfkill_led_trigger_activate(struct led_classdev *led)
 144 {
 145         struct rfkill *rfkill;
 146
 147         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 148
 149         rfkill_led_trigger_event(rfkill);
 150 }
 151
 152 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 153 {
 154         return rfkill->led_trigger.name;
 155 }
 156 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 157
 158 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 159 {
 160         BUG_ON(!rfkill);
 161
 162         rfkill->ledtrigname = name;
 163 }
 164 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 165
 166 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 167 {
 168         rfkill->led_trigger.name = rfkill->ledtrigname
 169                                         ? : dev_name(&rfkill->dev);
 170         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 171         return led_trigger_register(&rfkill->led_trigger);
 172 }
 173
 174 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 175 {
 176         led_trigger_unregister(&rfkill->led_trigger);
 177 }
 178 #else
 179 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 180 {
 181 }
 182
 183 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 184 {
 185         return 0;
 186 }
 187
 188 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 189 {
 190 }
 191 #endif /* CONFIG_RFKILL_LEDS */
 192
 193 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 194                               enum rfkill_operation op)
 195 {
 196         unsigned long flags;
 197
 198         ev->idx = rfkill->idx;
 199         ev->type = rfkill->type;
 200         ev->op = op;
 201
 202         spin_lock_irqsave(&rfkill->lock, flags);
 203         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 204         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 205                                         RFKILL_BLOCK_SW_PREV));
 206         spin_unlock_irqrestore(&rfkill->lock, flags);
 207 }
 208
 209 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 210 {
 211         struct rfkill_data *data;
 212         struct rfkill_int_event *ev;
 213
 214         list_for_each_entry(data, &rfkill_fds, list) {
 215                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 216                 if (!ev)
 217                         continue;
 218                 rfkill_fill_event(&ev->ev, rfkill, op);
 219                 mutex_lock(&data->mtx);
 220                 list_add_tail(&ev->list, &data->events);
 221                 mutex_unlock(&data->mtx);
 222                 wake_up_interruptible(&data->read_wait);
 223         }
 224 }
 225
 226 static void rfkill_event(struct rfkill *rfkill)
 227 {
 228         if (!rfkill->registered || rfkill->suspended)
 229                 return;
 230
 231         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 232
 233         /* also send event to /dev/rfkill */
 234         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 235 }
 236
 237 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
 238                                   bool blocked, bool *change)
 239 {
 240         unsigned long flags;
 241         bool prev, any;
 242
 243         BUG_ON(!rfkill);
 244
 245         spin_lock_irqsave(&rfkill->lock, flags);
 246         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 247         if (blocked)
 248                 rfkill->state |= RFKILL_BLOCK_HW;
 249         else
 250                 rfkill->state &= ~RFKILL_BLOCK_HW;
 251         *change = prev != blocked;
 252         any = rfkill->state & RFKILL_BLOCK_ANY;
 253         spin_unlock_irqrestore(&rfkill->lock, flags);
 254
 255         rfkill_led_trigger_event(rfkill);
 256
 257         return any;
 258 }
 259
 260 /**
 261  * rfkill_set_block - wrapper for set_block method
 262  *
 263  * @rfkill: the rfkill struct to use
 264  * @blocked: the new software state
 265  *
 266  * Calls the set_block method (when applicable) and handles notifications
 267  * etc. as well.
 268  */
 269 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 270 {
 271         unsigned long flags;
 272         int err;
 273
 274         /*
 275          * Some platforms (...!) generate input events which affect the
 276          * _hard_ kill state -- whenever something tries to change the
 277          * current software state query the hardware state too.
 278          */
 279         if (rfkill->ops->query)
 280                 rfkill->ops->query(rfkill, rfkill->data);
 281
 282         spin_lock_irqsave(&rfkill->lock, flags);
 283         if (rfkill->state & RFKILL_BLOCK_SW)
 284                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 285         else
 286                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 287
 288         if (blocked)
 289                 rfkill->state |= RFKILL_BLOCK_SW;
 290         else
 291                 rfkill->state &= ~RFKILL_BLOCK_SW;
 292
 293         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 294         spin_unlock_irqrestore(&rfkill->lock, flags);
 295
 296         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 297                 return;
 298
 299         err = rfkill->ops->set_block(rfkill->data, blocked);
 300
 301         spin_lock_irqsave(&rfkill->lock, flags);
 302         if (err) {
 303                 /*
 304                  * Failed -- reset status to _prev, this may be different
 305                  * from what set set _PREV to earlier in this function
 306                  * if rfkill_set_sw_state was invoked.
 307                  */
 308                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 309                         rfkill->state |= RFKILL_BLOCK_SW;
 310                 else
 311                         rfkill->state &= ~RFKILL_BLOCK_SW;
 312         }
 313         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 314         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 315         spin_unlock_irqrestore(&rfkill->lock, flags);
 316
 317         rfkill_led_trigger_event(rfkill);
 318         rfkill_event(rfkill);
 319 }
 320
 321 #ifdef CONFIG_RFKILL_INPUT
 322 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 323
 324 /**
 325  * __rfkill_switch_all - Toggle state of all switches of given type
 326  * @type: type of interfaces to be affected
 327  * @state: the new state
 328  *
 329  * This function sets the state of all switches of given type,
 330  * unless a specific switch is claimed by userspace (in which case,
 331  * that switch is left alone) or suspended.
 332  *
 333  * Caller must have acquired rfkill_global_mutex.
 334  */
 335 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 336 {
 337         struct rfkill *rfkill;
 338
 339         rfkill_global_states[type].cur = blocked;
 340         list_for_each_entry(rfkill, &rfkill_list, node) {
 341                 if (rfkill->type != type)
 342                         continue;
 343
 344                 rfkill_set_block(rfkill, blocked);
 345         }
 346 }
 347
 348 /**
 349  * rfkill_switch_all - Toggle state of all switches of given type
 350  * @type: type of interfaces to be affected
 351  * @state: the new state
 352  *
 353  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 354  * Please refer to __rfkill_switch_all() for details.
 355  *
 356  * Does nothing if the EPO lock is active.
 357  */
 358 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 359 {
 360         if (atomic_read(&rfkill_input_disabled))
 361                 return;
 362
 363         mutex_lock(&rfkill_global_mutex);
 364
 365         if (!rfkill_epo_lock_active)
 366                 __rfkill_switch_all(type, blocked);
 367
 368         mutex_unlock(&rfkill_global_mutex);
 369 }
 370
 371 /**
 372  * rfkill_epo - emergency power off all transmitters
 373  *
 374  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 375  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 376  *
 377  * The global state before the EPO is saved and can be restored later
 378  * using rfkill_restore_states().
 379  */
 380 void rfkill_epo(void)
 381 {
 382         struct rfkill *rfkill;
 383         int i;
 384
 385         if (atomic_read(&rfkill_input_disabled))
 386                 return;
 387
 388         mutex_lock(&rfkill_global_mutex);
 389
 390         rfkill_epo_lock_active = true;
 391         list_for_each_entry(rfkill, &rfkill_list, node)
 392                 rfkill_set_block(rfkill, true);
 393
 394         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 395                 rfkill_global_states[i].def = rfkill_global_states[i].cur;
 396                 rfkill_global_states[i].cur = true;
 397         }
 398
 399         mutex_unlock(&rfkill_global_mutex);
 400 }
 401
 402 /**
 403  * rfkill_restore_states - restore global states
 404  *
 405  * Restore (and sync switches to) the global state from the
 406  * states in rfkill_default_states.  This can undo the effects of
 407  * a call to rfkill_epo().
 408  */
 409 void rfkill_restore_states(void)
 410 {
 411         int i;
 412
 413         if (atomic_read(&rfkill_input_disabled))
 414                 return;
 415
 416         mutex_lock(&rfkill_global_mutex);
 417
 418         rfkill_epo_lock_active = false;
 419         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 420                 __rfkill_switch_all(i, rfkill_global_states[i].def);
 421         mutex_unlock(&rfkill_global_mutex);
 422 }
 423
 424 /**
 425  * rfkill_remove_epo_lock - unlock state changes
 426  *
 427  * Used by rfkill-input manually unlock state changes, when
 428  * the EPO switch is deactivated.
 429  */
 430 void rfkill_remove_epo_lock(void)
 431 {
 432         if (atomic_read(&rfkill_input_disabled))
 433                 return;
 434
 435         mutex_lock(&rfkill_global_mutex);
 436         rfkill_epo_lock_active = false;
 437         mutex_unlock(&rfkill_global_mutex);
 438 }
 439
 440 /**
 441  * rfkill_is_epo_lock_active - returns true EPO is active
 442  *
 443  * Returns 0 (false) if there is NOT an active EPO contidion,
 444  * and 1 (true) if there is an active EPO contition, which
 445  * locks all radios in one of the BLOCKED states.
 446  *
 447  * Can be called in atomic context.
 448  */
 449 bool rfkill_is_epo_lock_active(void)
 450 {
 451         return rfkill_epo_lock_active;
 452 }
 453
 454 /**
 455  * rfkill_get_global_sw_state - returns global state for a type
 456  * @type: the type to get the global state of
 457  *
 458  * Returns the current global state for a given wireless
 459  * device type.
 460  */
 461 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 462 {
 463         return rfkill_global_states[type].cur;
 464 }
 465 #endif
 466
 467 void rfkill_set_global_sw_state(const enum rfkill_type type, bool blocked)
 468 {
 469         BUG_ON(type == RFKILL_TYPE_ALL);
 470
 471         mutex_lock(&rfkill_global_mutex);
 472
 473         /* don't allow unblock when epo */
 474         if (rfkill_epo_lock_active && !blocked)
 475                 goto out;
 476
 477         /* too late */
 478         if (rfkill_states_default_locked & BIT(type))
 479                 goto out;
 480
 481         rfkill_states_default_locked |= BIT(type);
 482
 483         rfkill_global_states[type].cur = blocked;
 484         rfkill_global_states[type].def = blocked;
 485  out:
 486         mutex_unlock(&rfkill_global_mutex);
 487 }
 488 EXPORT_SYMBOL(rfkill_set_global_sw_state);
 489
 490
 491 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 492 {
 493         bool ret, change;
 494
 495         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 496
 497         if (!rfkill->registered)
 498                 return ret;
 499
 500         if (change)
 501                 schedule_work(&rfkill->uevent_work);
 502
 503         return ret;
 504 }
 505 EXPORT_SYMBOL(rfkill_set_hw_state);
 506
 507 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 508 {
 509         u32 bit = RFKILL_BLOCK_SW;
 510
 511         /* if in a ops->set_block right now, use other bit */
 512         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 513                 bit = RFKILL_BLOCK_SW_PREV;
 514
 515         if (blocked)
 516                 rfkill->state |= bit;
 517         else
 518                 rfkill->state &= ~bit;
 519 }
 520
 521 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 522 {
 523         unsigned long flags;
 524         bool prev, hwblock;
 525
 526         BUG_ON(!rfkill);
 527
 528         spin_lock_irqsave(&rfkill->lock, flags);
 529         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 530         __rfkill_set_sw_state(rfkill, blocked);
 531         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 532         blocked = blocked || hwblock;
 533         spin_unlock_irqrestore(&rfkill->lock, flags);
 534
 535         if (!rfkill->registered)
 536                 return blocked;
 537
 538         if (prev != blocked && !hwblock)
 539                 schedule_work(&rfkill->uevent_work);
 540
 541         rfkill_led_trigger_event(rfkill);
 542
 543         return blocked;
 544 }
 545 EXPORT_SYMBOL(rfkill_set_sw_state);
 546
 547 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 548 {
 549         unsigned long flags;
 550         bool swprev, hwprev;
 551
 552         BUG_ON(!rfkill);
 553
 554         spin_lock_irqsave(&rfkill->lock, flags);
 555
 556         /*
 557          * No need to care about prev/setblock ... this is for uevent only
 558          * and that will get triggered by rfkill_set_block anyway.
 559          */
 560         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 561         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 562         __rfkill_set_sw_state(rfkill, sw);
 563
 564         spin_unlock_irqrestore(&rfkill->lock, flags);
 565
 566         if (!rfkill->registered)
 567                 return;
 568
 569         if (swprev != sw || hwprev != hw)
 570                 schedule_work(&rfkill->uevent_work);
 571
 572         rfkill_led_trigger_event(rfkill);
 573 }
 574 EXPORT_SYMBOL(rfkill_set_states);
 575
 576 static ssize_t rfkill_name_show(struct device *dev,
 577                                 struct device_attribute *attr,
 578                                 char *buf)
 579 {
 580         struct rfkill *rfkill = to_rfkill(dev);
 581
 582         return sprintf(buf, "%s\n", rfkill->name);
 583 }
 584
 585 static const char *rfkill_get_type_str(enum rfkill_type type)
 586 {
 587         switch (type) {
 588         case RFKILL_TYPE_WLAN:
 589                 return "wlan";
 590         case RFKILL_TYPE_BLUETOOTH:
 591                 return "bluetooth";
 592         case RFKILL_TYPE_UWB:
 593                 return "ultrawideband";
 594         case RFKILL_TYPE_WIMAX:
 595                 return "wimax";
 596         case RFKILL_TYPE_WWAN:
 597                 return "wwan";
 598         default:
 599                 BUG();
 600         }
 601
 602         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_WWAN + 1);
 603 }
 604
 605 static ssize_t rfkill_type_show(struct device *dev,
 606                                 struct device_attribute *attr,
 607                                 char *buf)
 608 {
 609         struct rfkill *rfkill = to_rfkill(dev);
 610
 611         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 612 }
 613
 614 static ssize_t rfkill_idx_show(struct device *dev,
 615                                struct device_attribute *attr,
 616                                char *buf)
 617 {
 618         struct rfkill *rfkill = to_rfkill(dev);
 619
 620         return sprintf(buf, "%d\n", rfkill->idx);
 621 }
 622
 623 static u8 user_state_from_blocked(unsigned long state)
 624 {
 625         if (state & RFKILL_BLOCK_HW)
 626                 return RFKILL_USER_STATE_HARD_BLOCKED;
 627         if (state & RFKILL_BLOCK_SW)
 628                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 629
 630         return RFKILL_USER_STATE_UNBLOCKED;
 631 }
 632
 633 static ssize_t rfkill_state_show(struct device *dev,
 634                                  struct device_attribute *attr,
 635                                  char *buf)
 636 {
 637         struct rfkill *rfkill = to_rfkill(dev);
 638         unsigned long flags;
 639         u32 state;
 640
 641         spin_lock_irqsave(&rfkill->lock, flags);
 642         state = rfkill->state;
 643         spin_unlock_irqrestore(&rfkill->lock, flags);
 644
 645         return sprintf(buf, "%d\n", user_state_from_blocked(state));
 646 }
 647
 648 static ssize_t rfkill_state_store(struct device *dev,
 649                                   struct device_attribute *attr,
 650                                   const char *buf, size_t count)
 651 {
 652         /*
 653          * The intention was that userspace can only take control over
 654          * a given device when/if rfkill-input doesn't control it due
 655          * to user_claim. Since user_claim is currently unsupported,
 656          * we never support changing the state from userspace -- this
 657          * can be implemented again later.
 658          */
 659
 660         return -EPERM;
 661 }
 662
 663 static ssize_t rfkill_claim_show(struct device *dev,
 664                                  struct device_attribute *attr,
 665                                  char *buf)
 666 {
 667         return sprintf(buf, "%d\n", 0);
 668 }
 669
 670 static ssize_t rfkill_claim_store(struct device *dev,
 671                                   struct device_attribute *attr,
 672                                   const char *buf, size_t count)
 673 {
 674         return -EOPNOTSUPP;
 675 }
 676
 677 static struct device_attribute rfkill_dev_attrs[] = {
 678         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 679         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 680         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
 681         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 682         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 683         __ATTR_NULL
 684 };
 685
 686 static void rfkill_release(struct device *dev)
 687 {
 688         struct rfkill *rfkill = to_rfkill(dev);
 689
 690         kfree(rfkill);
 691 }
 692
 693 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 694 {
 695         struct rfkill *rfkill = to_rfkill(dev);
 696         unsigned long flags;
 697         u32 state;
 698         int error;
 699
 700         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 701         if (error)
 702                 return error;
 703         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 704                                rfkill_get_type_str(rfkill->type));
 705         if (error)
 706                 return error;
 707         spin_lock_irqsave(&rfkill->lock, flags);
 708         state = rfkill->state;
 709         spin_unlock_irqrestore(&rfkill->lock, flags);
 710         error = add_uevent_var(env, "RFKILL_STATE=%d",
 711                                user_state_from_blocked(state));
 712         return error;
 713 }
 714
 715 void rfkill_pause_polling(struct rfkill *rfkill)
 716 {
 717         BUG_ON(!rfkill);
 718
 719         if (!rfkill->ops->poll)
 720                 return;
 721
 722         cancel_delayed_work_sync(&rfkill->poll_work);
 723 }
 724 EXPORT_SYMBOL(rfkill_pause_polling);
 725
 726 void rfkill_resume_polling(struct rfkill *rfkill)
 727 {
 728         BUG_ON(!rfkill);
 729
 730         if (!rfkill->ops->poll)
 731                 return;
 732
 733         schedule_work(&rfkill->poll_work.work);
 734 }
 735 EXPORT_SYMBOL(rfkill_resume_polling);
 736
 737 static int rfkill_suspend(struct device *dev, pm_message_t state)
 738 {
 739         struct rfkill *rfkill = to_rfkill(dev);
 740
 741         rfkill_pause_polling(rfkill);
 742
 743         rfkill->suspended = true;
 744
 745         return 0;
 746 }
 747
 748 static int rfkill_resume(struct device *dev)
 749 {
 750         struct rfkill *rfkill = to_rfkill(dev);
 751         bool cur;
 752
 753         mutex_lock(&rfkill_global_mutex);
 754         cur = rfkill_global_states[rfkill->type].cur;
 755         rfkill_set_block(rfkill, cur);
 756         mutex_unlock(&rfkill_global_mutex);
 757
 758         rfkill->suspended = false;
 759
 760         schedule_work(&rfkill->uevent_work);
 761
 762         rfkill_resume_polling(rfkill);
 763
 764         return 0;
 765 }
 766
 767 static struct class rfkill_class = {
 768         .name           = "rfkill",
 769         .dev_release    = rfkill_release,
 770         .dev_attrs      = rfkill_dev_attrs,
 771         .dev_uevent     = rfkill_dev_uevent,
 772         .suspend        = rfkill_suspend,
 773         .resume         = rfkill_resume,
 774 };
 775
 776
 777 struct rfkill * __must_check rfkill_alloc(const char *name,
 778                                           struct device *parent,
 779                                           const enum rfkill_type type,
 780                                           const struct rfkill_ops *ops,
 781                                           void *ops_data)
 782 {
 783         struct rfkill *rfkill;
 784         struct device *dev;
 785
 786         if (WARN_ON(!ops))
 787                 return NULL;
 788
 789         if (WARN_ON(!ops->set_block))
 790                 return NULL;
 791
 792         if (WARN_ON(!name))
 793                 return NULL;
 794
 795         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 796                 return NULL;
 797
 798         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 799         if (!rfkill)
 800                 return NULL;
 801
 802         spin_lock_init(&rfkill->lock);
 803         INIT_LIST_HEAD(&rfkill->node);
 804         rfkill->type = type;
 805         rfkill->name = name;
 806         rfkill->ops = ops;
 807         rfkill->data = ops_data;
 808
 809         dev = &rfkill->dev;
 810         dev->class = &rfkill_class;
 811         dev->parent = parent;
 812         device_initialize(dev);
 813
 814         return rfkill;
 815 }
 816 EXPORT_SYMBOL(rfkill_alloc);
 817
 818 static void rfkill_poll(struct work_struct *work)
 819 {
 820         struct rfkill *rfkill;
 821
 822         rfkill = container_of(work, struct rfkill, poll_work.work);
 823
 824         /*
 825          * Poll hardware state -- driver will use one of the
 826          * rfkill_set{,_hw,_sw}_state functions and use its
 827          * return value to update the current status.
 828          */
 829         rfkill->ops->poll(rfkill, rfkill->data);
 830
 831         schedule_delayed_work(&rfkill->poll_work,
 832                 round_jiffies_relative(POLL_INTERVAL));
 833 }
 834
 835 static void rfkill_uevent_work(struct work_struct *work)
 836 {
 837         struct rfkill *rfkill;
 838
 839         rfkill = container_of(work, struct rfkill, uevent_work);
 840
 841         mutex_lock(&rfkill_global_mutex);
 842         rfkill_event(rfkill);
 843         mutex_unlock(&rfkill_global_mutex);
 844 }
 845
 846 static void rfkill_sync_work(struct work_struct *work)
 847 {
 848         struct rfkill *rfkill;
 849         bool cur;
 850
 851         rfkill = container_of(work, struct rfkill, sync_work);
 852
 853         mutex_lock(&rfkill_global_mutex);
 854         cur = rfkill_global_states[rfkill->type].cur;
 855         rfkill_set_block(rfkill, cur);
 856         mutex_unlock(&rfkill_global_mutex);
 857 }
 858
 859 int __must_check rfkill_register(struct rfkill *rfkill)
 860 {
 861         static unsigned long rfkill_no;
 862         struct device *dev = &rfkill->dev;
 863         int error;
 864
 865         BUG_ON(!rfkill);
 866
 867         mutex_lock(&rfkill_global_mutex);
 868
 869         if (rfkill->registered) {
 870                 error = -EALREADY;
 871                 goto unlock;
 872         }
 873
 874         rfkill->idx = rfkill_no;
 875         dev_set_name(dev, "rfkill%lu", rfkill_no);
 876         rfkill_no++;
 877
 878         if (!(rfkill_states_default_locked & BIT(rfkill->type))) {
 879                 /* first of its kind */
 880                 BUILD_BUG_ON(NUM_RFKILL_TYPES >
 881                         sizeof(rfkill_states_default_locked) * 8);
 882                 rfkill_states_default_locked |= BIT(rfkill->type);
 883                 rfkill_global_states[rfkill->type].cur =
 884                         rfkill_global_states[rfkill->type].def;
 885         }
 886
 887         list_add_tail(&rfkill->node, &rfkill_list);
 888
 889         error = device_add(dev);
 890         if (error)
 891                 goto remove;
 892
 893         error = rfkill_led_trigger_register(rfkill);
 894         if (error)
 895                 goto devdel;
 896
 897         rfkill->registered = true;
 898
 899         if (rfkill->ops->poll) {
 900                 INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 901                 schedule_delayed_work(&rfkill->poll_work,
 902                         round_jiffies_relative(POLL_INTERVAL));
 903         }
 904
 905         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 906
 907         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 908         schedule_work(&rfkill->sync_work);
 909         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 910
 911         mutex_unlock(&rfkill_global_mutex);
 912         return 0;
 913
 914  devdel:
 915         device_del(&rfkill->dev);
 916  remove:
 917         list_del_init(&rfkill->node);
 918  unlock:
 919         mutex_unlock(&rfkill_global_mutex);
 920         return error;
 921 }
 922 EXPORT_SYMBOL(rfkill_register);
 923
 924 void rfkill_unregister(struct rfkill *rfkill)
 925 {
 926         BUG_ON(!rfkill);
 927
 928         if (rfkill->ops->poll)
 929                 cancel_delayed_work_sync(&rfkill->poll_work);
 930
 931         cancel_work_sync(&rfkill->uevent_work);
 932         cancel_work_sync(&rfkill->sync_work);
 933
 934         rfkill->registered = false;
 935
 936         device_del(&rfkill->dev);
 937
 938         mutex_lock(&rfkill_global_mutex);
 939         rfkill_send_events(rfkill, RFKILL_OP_DEL);
 940         list_del_init(&rfkill->node);
 941         mutex_unlock(&rfkill_global_mutex);
 942
 943         rfkill_led_trigger_unregister(rfkill);
 944 }
 945 EXPORT_SYMBOL(rfkill_unregister);
 946
 947 void rfkill_destroy(struct rfkill *rfkill)
 948 {
 949         if (rfkill)
 950                 put_device(&rfkill->dev);
 951 }
 952 EXPORT_SYMBOL(rfkill_destroy);
 953
 954 static int rfkill_fop_open(struct inode *inode, struct file *file)
 955 {
 956         struct rfkill_data *data;
 957         struct rfkill *rfkill;
 958         struct rfkill_int_event *ev, *tmp;
 959
 960         data = kzalloc(sizeof(*data), GFP_KERNEL);
 961         if (!data)
 962                 return -ENOMEM;
 963
 964         INIT_LIST_HEAD(&data->events);
 965         mutex_init(&data->mtx);
 966         init_waitqueue_head(&data->read_wait);
 967
 968         mutex_lock(&rfkill_global_mutex);
 969         mutex_lock(&data->mtx);
 970         /*
 971          * start getting events from elsewhere but hold mtx to get
 972          * startup events added first
 973          */
 974         list_add(&data->list, &rfkill_fds);
 975
 976         list_for_each_entry(rfkill, &rfkill_list, node) {
 977                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 978                 if (!ev)
 979                         goto free;
 980                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
 981                 list_add_tail(&ev->list, &data->events);
 982         }
 983         mutex_unlock(&data->mtx);
 984         mutex_unlock(&rfkill_global_mutex);
 985
 986         file->private_data = data;
 987
 988         return nonseekable_open(inode, file);
 989
 990  free:
 991         mutex_unlock(&data->mtx);
 992         mutex_unlock(&rfkill_global_mutex);
 993         mutex_destroy(&data->mtx);
 994         list_for_each_entry_safe(ev, tmp, &data->events, list)
 995                 kfree(ev);
 996         kfree(data);
 997         return -ENOMEM;
 998 }
 999
1000 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1001 {
1002         struct rfkill_data *data = file->private_data;
1003         unsigned int res = POLLOUT | POLLWRNORM;
1004
1005         poll_wait(file, &data->read_wait, wait);
1006
1007         mutex_lock(&data->mtx);
1008         if (!list_empty(&data->events))
1009                 res = POLLIN | POLLRDNORM;
1010         mutex_unlock(&data->mtx);
1011
1012         return res;
1013 }
1014
1015 static bool rfkill_readable(struct rfkill_data *data)
1016 {
1017         bool r;
1018
1019         mutex_lock(&data->mtx);
1020         r = !list_empty(&data->events);
1021         mutex_unlock(&data->mtx);
1022
1023         return r;
1024 }
1025
1026 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1027                                size_t count, loff_t *pos)
1028 {
1029         struct rfkill_data *data = file->private_data;
1030         struct rfkill_int_event *ev;
1031         unsigned long sz;
1032         int ret;
1033
1034         mutex_lock(&data->mtx);
1035
1036         while (list_empty(&data->events)) {
1037                 if (file->f_flags & O_NONBLOCK) {
1038                         ret = -EAGAIN;
1039                         goto out;
1040                 }
1041                 mutex_unlock(&data->mtx);
1042                 ret = wait_event_interruptible(data->read_wait,
1043                                                rfkill_readable(data));
1044                 mutex_lock(&data->mtx);
1045
1046                 if (ret)
1047                         goto out;
1048         }
1049
1050         ev = list_first_entry(&data->events, struct rfkill_int_event,
1051                                 list);
1052
1053         sz = min_t(unsigned long, sizeof(ev->ev), count);
1054         ret = sz;
1055         if (copy_to_user(buf, &ev->ev, sz))
1056                 ret = -EFAULT;
1057
1058         list_del(&ev->list);
1059         kfree(ev);
1060  out:
1061         mutex_unlock(&data->mtx);
1062         return ret;
1063 }
1064
1065 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1066                                 size_t count, loff_t *pos)
1067 {
1068         struct rfkill *rfkill;
1069         struct rfkill_event ev;
1070
1071         /* we don't need the 'hard' variable but accept it */
1072         if (count < sizeof(ev) - 1)
1073                 return -EINVAL;
1074
1075         if (copy_from_user(&ev, buf, sizeof(ev) - 1))
1076                 return -EFAULT;
1077
1078         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1079                 return -EINVAL;
1080
1081         if (ev.type >= NUM_RFKILL_TYPES)
1082                 return -EINVAL;
1083
1084         mutex_lock(&rfkill_global_mutex);
1085
1086         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1087                 if (ev.type == RFKILL_TYPE_ALL) {
1088                         enum rfkill_type i;
1089                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1090                                 rfkill_global_states[i].cur = ev.soft;
1091                 } else {
1092                         rfkill_global_states[ev.type].cur = ev.soft;
1093                 }
1094         }
1095
1096         list_for_each_entry(rfkill, &rfkill_list, node) {
1097                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1098                         continue;
1099
1100                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1101                         continue;
1102
1103                 rfkill_set_block(rfkill, ev.soft);
1104         }
1105         mutex_unlock(&rfkill_global_mutex);
1106
1107         return count;
1108 }
1109
1110 static int rfkill_fop_release(struct inode *inode, struct file *file)
1111 {
1112         struct rfkill_data *data = file->private_data;
1113         struct rfkill_int_event *ev, *tmp;
1114
1115         mutex_lock(&rfkill_global_mutex);
1116         list_del(&data->list);
1117         mutex_unlock(&rfkill_global_mutex);
1118
1119         mutex_destroy(&data->mtx);
1120         list_for_each_entry_safe(ev, tmp, &data->events, list)
1121                 kfree(ev);
1122
1123 #ifdef CONFIG_RFKILL_INPUT
1124         if (data->input_handler)
1125                 atomic_dec(&rfkill_input_disabled);
1126 #endif
1127
1128         kfree(data);
1129
1130         return 0;
1131 }
1132
1133 #ifdef CONFIG_RFKILL_INPUT
1134 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1135                              unsigned long arg)
1136 {
1137         struct rfkill_data *data = file->private_data;
1138
1139         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1140                 return -ENOSYS;
1141
1142         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1143                 return -ENOSYS;
1144
1145         mutex_lock(&data->mtx);
1146
1147         if (!data->input_handler) {
1148                 atomic_inc(&rfkill_input_disabled);
1149                 data->input_handler = true;
1150         }
1151
1152         mutex_unlock(&data->mtx);
1153
1154         return 0;
1155 }
1156 #endif
1157
1158 static const struct file_operations rfkill_fops = {
1159         .open           = rfkill_fop_open,
1160         .read           = rfkill_fop_read,
1161         .write          = rfkill_fop_write,
1162         .poll           = rfkill_fop_poll,
1163         .release        = rfkill_fop_release,
1164 #ifdef CONFIG_RFKILL_INPUT
1165         .unlocked_ioctl = rfkill_fop_ioctl,
1166         .compat_ioctl   = rfkill_fop_ioctl,
1167 #endif
1168 };
1169
1170 static struct miscdevice rfkill_miscdev = {
1171         .name   = "rfkill",
1172         .fops   = &rfkill_fops,
1173         .minor  = MISC_DYNAMIC_MINOR,
1174 };
1175
1176 static int __init rfkill_init(void)
1177 {
1178         int error;
1179         int i;
1180
1181         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1182                 rfkill_global_states[i].def = !rfkill_default_state;
1183
1184         error = class_register(&rfkill_class);
1185         if (error)
1186                 goto out;
1187
1188         error = misc_register(&rfkill_miscdev);
1189         if (error) {
1190                 class_unregister(&rfkill_class);
1191                 goto out;
1192         }
1193
1194 #ifdef CONFIG_RFKILL_INPUT
1195         error = rfkill_handler_init();
1196         if (error) {
1197                 misc_deregister(&rfkill_miscdev);
1198                 class_unregister(&rfkill_class);
1199                 goto out;
1200         }
1201 #endif
1202
1203  out:
1204         return error;
1205 }
1206 subsys_initcall(rfkill_init);
1207
1208 static void __exit rfkill_exit(void)
1209 {
1210 #ifdef CONFIG_RFKILL_INPUT
1211         rfkill_handler_exit();
1212 #endif
1213         misc_deregister(&rfkill_miscdev);
1214         class_unregister(&rfkill_class);
1215 }
1216 module_exit(rfkill_exit);