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/sched.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/miscdevice.h>
  33 #include <linux/wait.h>
  34 #include <linux/poll.h>
  35 #include <linux/fs.h>
  36
  37 #include "rfkill.h"
  38
  39 #define POLL_INTERVAL           (5 * HZ)
  40
  41 #define RFKILL_BLOCK_HW         BIT(0)
  42 #define RFKILL_BLOCK_SW         BIT(1)
  43 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  44 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  45                                  RFKILL_BLOCK_SW |\
  46                                  RFKILL_BLOCK_SW_PREV)
  47 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  48
  49 struct rfkill {
  50         spinlock_t              lock;
  51
  52         const char              *name;
  53         enum rfkill_type        type;
  54
  55         unsigned long           state;
  56
  57         u32                     idx;
  58
  59         bool                    registered;
  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)
 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         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 274                 return;
 275
 276         /*
 277          * Some platforms (...!) generate input events which affect the
 278          * _hard_ kill state -- whenever something tries to change the
 279          * current software state query the hardware state too.
 280          */
 281         if (rfkill->ops->query)
 282                 rfkill->ops->query(rfkill, rfkill->data);
 283
 284         spin_lock_irqsave(&rfkill->lock, flags);
 285         if (rfkill->state & RFKILL_BLOCK_SW)
 286                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 287         else
 288                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 289
 290         if (blocked)
 291                 rfkill->state |= RFKILL_BLOCK_SW;
 292         else
 293                 rfkill->state &= ~RFKILL_BLOCK_SW;
 294
 295         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 296         spin_unlock_irqrestore(&rfkill->lock, flags);
 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                 return blocked;
 513
 514         if (prev != blocked && !hwblock)
 515                 schedule_work(&rfkill->uevent_work);
 516
 517         rfkill_led_trigger_event(rfkill);
 518
 519         return blocked;
 520 }
 521 EXPORT_SYMBOL(rfkill_set_sw_state);
 522
 523 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 524 {
 525         unsigned long flags;
 526
 527         BUG_ON(!rfkill);
 528         BUG_ON(rfkill->registered);
 529
 530         spin_lock_irqsave(&rfkill->lock, flags);
 531         __rfkill_set_sw_state(rfkill, blocked);
 532         rfkill->persistent = true;
 533         spin_unlock_irqrestore(&rfkill->lock, flags);
 534 }
 535 EXPORT_SYMBOL(rfkill_init_sw_state);
 536
 537 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 538 {
 539         unsigned long flags;
 540         bool swprev, hwprev;
 541
 542         BUG_ON(!rfkill);
 543
 544         spin_lock_irqsave(&rfkill->lock, flags);
 545
 546         /*
 547          * No need to care about prev/setblock ... this is for uevent only
 548          * and that will get triggered by rfkill_set_block anyway.
 549          */
 550         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 551         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 552         __rfkill_set_sw_state(rfkill, sw);
 553         if (hw)
 554                 rfkill->state |= RFKILL_BLOCK_HW;
 555         else
 556                 rfkill->state &= ~RFKILL_BLOCK_HW;
 557
 558         spin_unlock_irqrestore(&rfkill->lock, flags);
 559
 560         if (!rfkill->registered) {
 561                 rfkill->persistent = true;
 562         } else {
 563                 if (swprev != sw || hwprev != hw)
 564                         schedule_work(&rfkill->uevent_work);
 565
 566                 rfkill_led_trigger_event(rfkill);
 567         }
 568 }
 569 EXPORT_SYMBOL(rfkill_set_states);
 570
 571 static ssize_t rfkill_name_show(struct device *dev,
 572                                 struct device_attribute *attr,
 573                                 char *buf)
 574 {
 575         struct rfkill *rfkill = to_rfkill(dev);
 576
 577         return sprintf(buf, "%s\n", rfkill->name);
 578 }
 579
 580 static const char *rfkill_get_type_str(enum rfkill_type type)
 581 {
 582         switch (type) {
 583         case RFKILL_TYPE_WLAN:
 584                 return "wlan";
 585         case RFKILL_TYPE_BLUETOOTH:
 586                 return "bluetooth";
 587         case RFKILL_TYPE_UWB:
 588                 return "ultrawideband";
 589         case RFKILL_TYPE_WIMAX:
 590                 return "wimax";
 591         case RFKILL_TYPE_WWAN:
 592                 return "wwan";
 593         case RFKILL_TYPE_GPS:
 594                 return "gps";
 595         case RFKILL_TYPE_FM:
 596                 return "fm";
 597         default:
 598                 BUG();
 599         }
 600
 601         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_FM + 1);
 602 }
 603
 604 static ssize_t rfkill_type_show(struct device *dev,
 605                                 struct device_attribute *attr,
 606                                 char *buf)
 607 {
 608         struct rfkill *rfkill = to_rfkill(dev);
 609
 610         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 611 }
 612
 613 static ssize_t rfkill_idx_show(struct device *dev,
 614                                struct device_attribute *attr,
 615                                char *buf)
 616 {
 617         struct rfkill *rfkill = to_rfkill(dev);
 618
 619         return sprintf(buf, "%d\n", rfkill->idx);
 620 }
 621
 622 static ssize_t rfkill_persistent_show(struct device *dev,
 623                                struct device_attribute *attr,
 624                                char *buf)
 625 {
 626         struct rfkill *rfkill = to_rfkill(dev);
 627
 628         return sprintf(buf, "%d\n", rfkill->persistent);
 629 }
 630
 631 static u8 user_state_from_blocked(unsigned long state)
 632 {
 633         if (state & RFKILL_BLOCK_HW)
 634                 return RFKILL_USER_STATE_HARD_BLOCKED;
 635         if (state & RFKILL_BLOCK_SW)
 636                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 637
 638         return RFKILL_USER_STATE_UNBLOCKED;
 639 }
 640
 641 static ssize_t rfkill_state_show(struct device *dev,
 642                                  struct device_attribute *attr,
 643                                  char *buf)
 644 {
 645         struct rfkill *rfkill = to_rfkill(dev);
 646         unsigned long flags;
 647         u32 state;
 648
 649         spin_lock_irqsave(&rfkill->lock, flags);
 650         state = rfkill->state;
 651         spin_unlock_irqrestore(&rfkill->lock, flags);
 652
 653         return sprintf(buf, "%d\n", user_state_from_blocked(state));
 654 }
 655
 656 static ssize_t rfkill_state_store(struct device *dev,
 657                                   struct device_attribute *attr,
 658                                   const char *buf, size_t count)
 659 {
 660         struct rfkill *rfkill = to_rfkill(dev);
 661         unsigned long state;
 662         int err;
 663
 664         if (!capable(CAP_NET_ADMIN))
 665                 return -EPERM;
 666
 667         err = strict_strtoul(buf, 0, &state);
 668         if (err)
 669                 return err;
 670
 671         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 672             state != RFKILL_USER_STATE_UNBLOCKED)
 673                 return -EINVAL;
 674
 675         mutex_lock(&rfkill_global_mutex);
 676         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 677         mutex_unlock(&rfkill_global_mutex);
 678
 679         return err ?: count;
 680 }
 681
 682 static ssize_t rfkill_claim_show(struct device *dev,
 683                                  struct device_attribute *attr,
 684                                  char *buf)
 685 {
 686         return sprintf(buf, "%d\n", 0);
 687 }
 688
 689 static ssize_t rfkill_claim_store(struct device *dev,
 690                                   struct device_attribute *attr,
 691                                   const char *buf, size_t count)
 692 {
 693         return -EOPNOTSUPP;
 694 }
 695
 696 static struct device_attribute rfkill_dev_attrs[] = {
 697         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 698         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 699         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
 700         __ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
 701         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 702         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 703         __ATTR_NULL
 704 };
 705
 706 static void rfkill_release(struct device *dev)
 707 {
 708         struct rfkill *rfkill = to_rfkill(dev);
 709
 710         kfree(rfkill);
 711 }
 712
 713 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 714 {
 715         struct rfkill *rfkill = to_rfkill(dev);
 716         unsigned long flags;
 717         u32 state;
 718         int error;
 719
 720         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 721         if (error)
 722                 return error;
 723         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 724                                rfkill_get_type_str(rfkill->type));
 725         if (error)
 726                 return error;
 727         spin_lock_irqsave(&rfkill->lock, flags);
 728         state = rfkill->state;
 729         spin_unlock_irqrestore(&rfkill->lock, flags);
 730         error = add_uevent_var(env, "RFKILL_STATE=%d",
 731                                user_state_from_blocked(state));
 732         return error;
 733 }
 734
 735 void rfkill_pause_polling(struct rfkill *rfkill)
 736 {
 737         BUG_ON(!rfkill);
 738
 739         if (!rfkill->ops->poll)
 740                 return;
 741
 742         cancel_delayed_work_sync(&rfkill->poll_work);
 743 }
 744 EXPORT_SYMBOL(rfkill_pause_polling);
 745
 746 void rfkill_resume_polling(struct rfkill *rfkill)
 747 {
 748         BUG_ON(!rfkill);
 749
 750         if (!rfkill->ops->poll)
 751                 return;
 752
 753         schedule_work(&rfkill->poll_work.work);
 754 }
 755 EXPORT_SYMBOL(rfkill_resume_polling);
 756
 757 static int rfkill_suspend(struct device *dev, pm_message_t state)
 758 {
 759         struct rfkill *rfkill = to_rfkill(dev);
 760
 761         rfkill_pause_polling(rfkill);
 762
 763         return 0;
 764 }
 765
 766 static int rfkill_resume(struct device *dev)
 767 {
 768         struct rfkill *rfkill = to_rfkill(dev);
 769         bool cur;
 770
 771         if (!rfkill->persistent) {
 772                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 773                 rfkill_set_block(rfkill, cur);
 774         }
 775
 776         rfkill_resume_polling(rfkill);
 777
 778         return 0;
 779 }
 780
 781 static struct class rfkill_class = {
 782         .name           = "rfkill",
 783         .dev_release    = rfkill_release,
 784         .dev_attrs      = rfkill_dev_attrs,
 785         .dev_uevent     = rfkill_dev_uevent,
 786         .suspend        = rfkill_suspend,
 787         .resume         = rfkill_resume,
 788 };
 789
 790 bool rfkill_blocked(struct rfkill *rfkill)
 791 {
 792         unsigned long flags;
 793         u32 state;
 794
 795         spin_lock_irqsave(&rfkill->lock, flags);
 796         state = rfkill->state;
 797         spin_unlock_irqrestore(&rfkill->lock, flags);
 798
 799         return !!(state & RFKILL_BLOCK_ANY);
 800 }
 801 EXPORT_SYMBOL(rfkill_blocked);
 802
 803
 804 struct rfkill * __must_check rfkill_alloc(const char *name,
 805                                           struct device *parent,
 806                                           const enum rfkill_type type,
 807                                           const struct rfkill_ops *ops,
 808                                           void *ops_data)
 809 {
 810         struct rfkill *rfkill;
 811         struct device *dev;
 812
 813         if (WARN_ON(!ops))
 814                 return NULL;
 815
 816         if (WARN_ON(!ops->set_block))
 817                 return NULL;
 818
 819         if (WARN_ON(!name))
 820                 return NULL;
 821
 822         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 823                 return NULL;
 824
 825         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 826         if (!rfkill)
 827                 return NULL;
 828
 829         spin_lock_init(&rfkill->lock);
 830         INIT_LIST_HEAD(&rfkill->node);
 831         rfkill->type = type;
 832         rfkill->name = name;
 833         rfkill->ops = ops;
 834         rfkill->data = ops_data;
 835
 836         dev = &rfkill->dev;
 837         dev->class = &rfkill_class;
 838         dev->parent = parent;
 839         device_initialize(dev);
 840
 841         return rfkill;
 842 }
 843 EXPORT_SYMBOL(rfkill_alloc);
 844
 845 static void rfkill_poll(struct work_struct *work)
 846 {
 847         struct rfkill *rfkill;
 848
 849         rfkill = container_of(work, struct rfkill, poll_work.work);
 850
 851         /*
 852          * Poll hardware state -- driver will use one of the
 853          * rfkill_set{,_hw,_sw}_state functions and use its
 854          * return value to update the current status.
 855          */
 856         rfkill->ops->poll(rfkill, rfkill->data);
 857
 858         schedule_delayed_work(&rfkill->poll_work,
 859                 round_jiffies_relative(POLL_INTERVAL));
 860 }
 861
 862 static void rfkill_uevent_work(struct work_struct *work)
 863 {
 864         struct rfkill *rfkill;
 865
 866         rfkill = container_of(work, struct rfkill, uevent_work);
 867
 868         mutex_lock(&rfkill_global_mutex);
 869         rfkill_event(rfkill);
 870         mutex_unlock(&rfkill_global_mutex);
 871 }
 872
 873 static void rfkill_sync_work(struct work_struct *work)
 874 {
 875         struct rfkill *rfkill;
 876         bool cur;
 877
 878         rfkill = container_of(work, struct rfkill, sync_work);
 879
 880         mutex_lock(&rfkill_global_mutex);
 881         cur = rfkill_global_states[rfkill->type].cur;
 882         rfkill_set_block(rfkill, cur);
 883         mutex_unlock(&rfkill_global_mutex);
 884 }
 885
 886 int __must_check rfkill_register(struct rfkill *rfkill)
 887 {
 888         static unsigned long rfkill_no;
 889         struct device *dev = &rfkill->dev;
 890         int error;
 891
 892         BUG_ON(!rfkill);
 893
 894         mutex_lock(&rfkill_global_mutex);
 895
 896         if (rfkill->registered) {
 897                 error = -EALREADY;
 898                 goto unlock;
 899         }
 900
 901         rfkill->idx = rfkill_no;
 902         dev_set_name(dev, "rfkill%lu", rfkill_no);
 903         rfkill_no++;
 904
 905         list_add_tail(&rfkill->node, &rfkill_list);
 906
 907         error = device_add(dev);
 908         if (error)
 909                 goto remove;
 910
 911         error = rfkill_led_trigger_register(rfkill);
 912         if (error)
 913                 goto devdel;
 914
 915         rfkill->registered = true;
 916
 917         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 918         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 919         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 920
 921         if (rfkill->ops->poll)
 922                 schedule_delayed_work(&rfkill->poll_work,
 923                         round_jiffies_relative(POLL_INTERVAL));
 924
 925         if (!rfkill->persistent || rfkill_epo_lock_active) {
 926                 schedule_work(&rfkill->sync_work);
 927         } else {
 928 #ifdef CONFIG_RFKILL_INPUT
 929                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 930
 931                 if (!atomic_read(&rfkill_input_disabled))
 932                         __rfkill_switch_all(rfkill->type, soft_blocked);
 933 #endif
 934         }
 935
 936         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 937
 938         mutex_unlock(&rfkill_global_mutex);
 939         return 0;
 940
 941  devdel:
 942         device_del(&rfkill->dev);
 943  remove:
 944         list_del_init(&rfkill->node);
 945  unlock:
 946         mutex_unlock(&rfkill_global_mutex);
 947         return error;
 948 }
 949 EXPORT_SYMBOL(rfkill_register);
 950
 951 void rfkill_unregister(struct rfkill *rfkill)
 952 {
 953         BUG_ON(!rfkill);
 954
 955         if (rfkill->ops->poll)
 956                 cancel_delayed_work_sync(&rfkill->poll_work);
 957
 958         cancel_work_sync(&rfkill->uevent_work);
 959         cancel_work_sync(&rfkill->sync_work);
 960
 961         rfkill->registered = false;
 962
 963         device_del(&rfkill->dev);
 964
 965         mutex_lock(&rfkill_global_mutex);
 966         rfkill_send_events(rfkill, RFKILL_OP_DEL);
 967         list_del_init(&rfkill->node);
 968         mutex_unlock(&rfkill_global_mutex);
 969
 970         rfkill_led_trigger_unregister(rfkill);
 971 }
 972 EXPORT_SYMBOL(rfkill_unregister);
 973
 974 void rfkill_destroy(struct rfkill *rfkill)
 975 {
 976         if (rfkill)
 977                 put_device(&rfkill->dev);
 978 }
 979 EXPORT_SYMBOL(rfkill_destroy);
 980
 981 static int rfkill_fop_open(struct inode *inode, struct file *file)
 982 {
 983         struct rfkill_data *data;
 984         struct rfkill *rfkill;
 985         struct rfkill_int_event *ev, *tmp;
 986
 987         data = kzalloc(sizeof(*data), GFP_KERNEL);
 988         if (!data)
 989                 return -ENOMEM;
 990
 991         INIT_LIST_HEAD(&data->events);
 992         mutex_init(&data->mtx);
 993         init_waitqueue_head(&data->read_wait);
 994
 995         mutex_lock(&rfkill_global_mutex);
 996         mutex_lock(&data->mtx);
 997         /*
 998          * start getting events from elsewhere but hold mtx to get
 999          * startup events added first
1000          */
1001         list_add(&data->list, &rfkill_fds);
1002
1003         list_for_each_entry(rfkill, &rfkill_list, node) {
1004                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1005                 if (!ev)
1006                         goto free;
1007                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1008                 list_add_tail(&ev->list, &data->events);
1009         }
1010         mutex_unlock(&data->mtx);
1011         mutex_unlock(&rfkill_global_mutex);
1012
1013         file->private_data = data;
1014
1015         return nonseekable_open(inode, file);
1016
1017  free:
1018         mutex_unlock(&data->mtx);
1019         mutex_unlock(&rfkill_global_mutex);
1020         mutex_destroy(&data->mtx);
1021         list_for_each_entry_safe(ev, tmp, &data->events, list)
1022                 kfree(ev);
1023         kfree(data);
1024         return -ENOMEM;
1025 }
1026
1027 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1028 {
1029         struct rfkill_data *data = file->private_data;
1030         unsigned int res = POLLOUT | POLLWRNORM;
1031
1032         poll_wait(file, &data->read_wait, wait);
1033
1034         mutex_lock(&data->mtx);
1035         if (!list_empty(&data->events))
1036                 res = POLLIN | POLLRDNORM;
1037         mutex_unlock(&data->mtx);
1038
1039         return res;
1040 }
1041
1042 static bool rfkill_readable(struct rfkill_data *data)
1043 {
1044         bool r;
1045
1046         mutex_lock(&data->mtx);
1047         r = !list_empty(&data->events);
1048         mutex_unlock(&data->mtx);
1049
1050         return r;
1051 }
1052
1053 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1054                                size_t count, loff_t *pos)
1055 {
1056         struct rfkill_data *data = file->private_data;
1057         struct rfkill_int_event *ev;
1058         unsigned long sz;
1059         int ret;
1060
1061         mutex_lock(&data->mtx);
1062
1063         while (list_empty(&data->events)) {
1064                 if (file->f_flags & O_NONBLOCK) {
1065                         ret = -EAGAIN;
1066                         goto out;
1067                 }
1068                 mutex_unlock(&data->mtx);
1069                 ret = wait_event_interruptible(data->read_wait,
1070                                                rfkill_readable(data));
1071                 mutex_lock(&data->mtx);
1072
1073                 if (ret)
1074                         goto out;
1075         }
1076
1077         ev = list_first_entry(&data->events, struct rfkill_int_event,
1078                                 list);
1079
1080         sz = min_t(unsigned long, sizeof(ev->ev), count);
1081         ret = sz;
1082         if (copy_to_user(buf, &ev->ev, sz))
1083                 ret = -EFAULT;
1084
1085         list_del(&ev->list);
1086         kfree(ev);
1087  out:
1088         mutex_unlock(&data->mtx);
1089         return ret;
1090 }
1091
1092 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1093                                 size_t count, loff_t *pos)
1094 {
1095         struct rfkill *rfkill;
1096         struct rfkill_event ev;
1097
1098         /* we don't need the 'hard' variable but accept it */
1099         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1100                 return -EINVAL;
1101
1102         /*
1103          * Copy as much data as we can accept into our 'ev' buffer,
1104          * but tell userspace how much we've copied so it can determine
1105          * our API version even in a write() call, if it cares.
1106          */
1107         count = min(count, sizeof(ev));
1108         if (copy_from_user(&ev, buf, count))
1109                 return -EFAULT;
1110
1111         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1112                 return -EINVAL;
1113
1114         if (ev.type >= NUM_RFKILL_TYPES)
1115                 return -EINVAL;
1116
1117         mutex_lock(&rfkill_global_mutex);
1118
1119         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1120                 if (ev.type == RFKILL_TYPE_ALL) {
1121                         enum rfkill_type i;
1122                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1123                                 rfkill_global_states[i].cur = ev.soft;
1124                 } else {
1125                         rfkill_global_states[ev.type].cur = ev.soft;
1126                 }
1127         }
1128
1129         list_for_each_entry(rfkill, &rfkill_list, node) {
1130                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1131                         continue;
1132
1133                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1134                         continue;
1135
1136                 rfkill_set_block(rfkill, ev.soft);
1137         }
1138         mutex_unlock(&rfkill_global_mutex);
1139
1140         return count;
1141 }
1142
1143 static int rfkill_fop_release(struct inode *inode, struct file *file)
1144 {
1145         struct rfkill_data *data = file->private_data;
1146         struct rfkill_int_event *ev, *tmp;
1147
1148         mutex_lock(&rfkill_global_mutex);
1149         list_del(&data->list);
1150         mutex_unlock(&rfkill_global_mutex);
1151
1152         mutex_destroy(&data->mtx);
1153         list_for_each_entry_safe(ev, tmp, &data->events, list)
1154                 kfree(ev);
1155
1156 #ifdef CONFIG_RFKILL_INPUT
1157         if (data->input_handler)
1158                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1159                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1160 #endif
1161
1162         kfree(data);
1163
1164         return 0;
1165 }
1166
1167 #ifdef CONFIG_RFKILL_INPUT
1168 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1169                              unsigned long arg)
1170 {
1171         struct rfkill_data *data = file->private_data;
1172
1173         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1174                 return -ENOSYS;
1175
1176         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1177                 return -ENOSYS;
1178
1179         mutex_lock(&data->mtx);
1180
1181         if (!data->input_handler) {
1182                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1183                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1184                 data->input_handler = true;
1185         }
1186
1187         mutex_unlock(&data->mtx);
1188
1189         return 0;
1190 }
1191 #endif
1192
1193 static const struct file_operations rfkill_fops = {
1194         .open           = rfkill_fop_open,
1195         .read           = rfkill_fop_read,
1196         .write          = rfkill_fop_write,
1197         .poll           = rfkill_fop_poll,
1198         .release        = rfkill_fop_release,
1199 #ifdef CONFIG_RFKILL_INPUT
1200         .unlocked_ioctl = rfkill_fop_ioctl,
1201         .compat_ioctl   = rfkill_fop_ioctl,
1202 #endif
1203 };
1204
1205 static struct miscdevice rfkill_miscdev = {
1206         .name   = "rfkill",
1207         .fops   = &rfkill_fops,
1208         .minor  = MISC_DYNAMIC_MINOR,
1209 };
1210
1211 static int __init rfkill_init(void)
1212 {
1213         int error;
1214         int i;
1215
1216         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1217                 rfkill_global_states[i].cur = !rfkill_default_state;
1218
1219         error = class_register(&rfkill_class);
1220         if (error)
1221                 goto out;
1222
1223         error = misc_register(&rfkill_miscdev);
1224         if (error) {
1225                 class_unregister(&rfkill_class);
1226                 goto out;
1227         }
1228
1229 #ifdef CONFIG_RFKILL_INPUT
1230         error = rfkill_handler_init();
1231         if (error) {
1232                 misc_deregister(&rfkill_miscdev);
1233                 class_unregister(&rfkill_class);
1234                 goto out;
1235         }
1236 #endif
1237
1238  out:
1239         return error;
1240 }
1241 subsys_initcall(rfkill_init);
1242
1243 static void __exit rfkill_exit(void)
1244 {
1245 #ifdef CONFIG_RFKILL_INPUT
1246         rfkill_handler_exit();
1247 #endif
1248         misc_deregister(&rfkill_miscdev);
1249         class_unregister(&rfkill_class);
1250 }
1251 module_exit(rfkill_exit);