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