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                    persistent;
  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, sav;
 120 } rfkill_global_states[NUM_RFKILL_TYPES];
 121
 122 static bool rfkill_epo_lock_active;
 123
 124
 125 #ifdef CONFIG_RFKILL_LEDS
 126 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 127 {
 128         struct led_trigger *trigger;
 129
 130         if (!rfkill->registered)
 131                 return;
 132
 133         trigger = &rfkill->led_trigger;
 134
 135         if (rfkill->state & RFKILL_BLOCK_ANY)
 136                 led_trigger_event(trigger, LED_OFF);
 137         else
 138                 led_trigger_event(trigger, LED_FULL);
 139 }
 140
 141 static void rfkill_led_trigger_activate(struct led_classdev *led)
 142 {
 143         struct rfkill *rfkill;
 144
 145         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 146
 147         rfkill_led_trigger_event(rfkill);
 148 }
 149
 150 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 151 {
 152         return rfkill->led_trigger.name;
 153 }
 154 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 155
 156 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 157 {
 158         BUG_ON(!rfkill);
 159
 160         rfkill->ledtrigname = name;
 161 }
 162 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 163
 164 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 165 {
 166         rfkill->led_trigger.name = rfkill->ledtrigname
 167                                         ? : dev_name(&rfkill->dev);
 168         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 169         return led_trigger_register(&rfkill->led_trigger);
 170 }
 171
 172 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 173 {
 174         led_trigger_unregister(&rfkill->led_trigger);
 175 }
 176 #else
 177 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 178 {
 179 }
 180
 181 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 182 {
 183         return 0;
 184 }
 185
 186 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 187 {
 188 }
 189 #endif /* CONFIG_RFKILL_LEDS */
 190
 191 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 192                               enum rfkill_operation op)
 193 {
 194         unsigned long flags;
 195
 196         ev->idx = rfkill->idx;
 197         ev->type = rfkill->type;
 198         ev->op = op;
 199
 200         spin_lock_irqsave(&rfkill->lock, flags);
 201         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 202         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 203                                         RFKILL_BLOCK_SW_PREV));
 204         spin_unlock_irqrestore(&rfkill->lock, flags);
 205 }
 206
 207 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 208 {
 209         struct rfkill_data *data;
 210         struct rfkill_int_event *ev;
 211
 212         list_for_each_entry(data, &rfkill_fds, list) {
 213                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 214                 if (!ev)
 215                         continue;
 216                 rfkill_fill_event(&ev->ev, rfkill, op);
 217                 mutex_lock(&data->mtx);
 218                 list_add_tail(&ev->list, &data->events);
 219                 mutex_unlock(&data->mtx);
 220                 wake_up_interruptible(&data->read_wait);
 221         }
 222 }
 223
 224 static void rfkill_event(struct rfkill *rfkill)
 225 {
 226         if (!rfkill->registered)
 227                 return;
 228
 229         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 230
 231         /* also send event to /dev/rfkill */
 232         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 233 }
 234
 235 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
 236                                   bool blocked, bool *change)
 237 {
 238         unsigned long flags;
 239         bool prev, any;
 240
 241         BUG_ON(!rfkill);
 242
 243         spin_lock_irqsave(&rfkill->lock, flags);
 244         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 245         if (blocked)
 246                 rfkill->state |= RFKILL_BLOCK_HW;
 247         else
 248                 rfkill->state &= ~RFKILL_BLOCK_HW;
 249         *change = prev != blocked;
 250         any = rfkill->state & RFKILL_BLOCK_ANY;
 251         spin_unlock_irqrestore(&rfkill->lock, flags);
 252
 253         rfkill_led_trigger_event(rfkill);
 254
 255         return any;
 256 }
 257
 258 /**
 259  * rfkill_set_block - wrapper for set_block method
 260  *
 261  * @rfkill: the rfkill struct to use
 262  * @blocked: the new software state
 263  *
 264  * Calls the set_block method (when applicable) and handles notifications
 265  * etc. as well.
 266  */
 267 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 268 {
 269         unsigned long flags;
 270         int err;
 271
 272         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 273                 return;
 274
 275         /*
 276          * Some platforms (...!) generate input events which affect the
 277          * _hard_ kill state -- whenever something tries to change the
 278          * current software state query the hardware state too.
 279          */
 280         if (rfkill->ops->query)
 281                 rfkill->ops->query(rfkill, rfkill->data);
 282
 283         spin_lock_irqsave(&rfkill->lock, flags);
 284         if (rfkill->state & RFKILL_BLOCK_SW)
 285                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 286         else
 287                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 288
 289         if (blocked)
 290                 rfkill->state |= RFKILL_BLOCK_SW;
 291         else
 292                 rfkill->state &= ~RFKILL_BLOCK_SW;
 293
 294         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 295         spin_unlock_irqrestore(&rfkill->lock, flags);
 296
 297         err = rfkill->ops->set_block(rfkill->data, blocked);
 298
 299         spin_lock_irqsave(&rfkill->lock, flags);
 300         if (err) {
 301                 /*
 302                  * Failed -- reset status to _prev, this may be different
 303                  * from what set set _PREV to earlier in this function
 304                  * if rfkill_set_sw_state was invoked.
 305                  */
 306                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 307                         rfkill->state |= RFKILL_BLOCK_SW;
 308                 else
 309                         rfkill->state &= ~RFKILL_BLOCK_SW;
 310         }
 311         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 312         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 313         spin_unlock_irqrestore(&rfkill->lock, flags);
 314
 315         rfkill_led_trigger_event(rfkill);
 316         rfkill_event(rfkill);
 317 }
 318
 319 #ifdef CONFIG_RFKILL_INPUT
 320 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 321
 322 /**
 323  * __rfkill_switch_all - Toggle state of all switches of given type
 324  * @type: type of interfaces to be affected
 325  * @state: the new state
 326  *
 327  * This function sets the state of all switches of given type,
 328  * unless a specific switch is claimed by userspace (in which case,
 329  * that switch is left alone) or suspended.
 330  *
 331  * Caller must have acquired rfkill_global_mutex.
 332  */
 333 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 334 {
 335         struct rfkill *rfkill;
 336
 337         rfkill_global_states[type].cur = blocked;
 338         list_for_each_entry(rfkill, &rfkill_list, node) {
 339                 if (rfkill->type != type)
 340                         continue;
 341
 342                 rfkill_set_block(rfkill, blocked);
 343         }
 344 }
 345
 346 /**
 347  * rfkill_switch_all - Toggle state of all switches of given type
 348  * @type: type of interfaces to be affected
 349  * @state: the new state
 350  *
 351  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 352  * Please refer to __rfkill_switch_all() for details.
 353  *
 354  * Does nothing if the EPO lock is active.
 355  */
 356 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 357 {
 358         if (atomic_read(&rfkill_input_disabled))
 359                 return;
 360
 361         mutex_lock(&rfkill_global_mutex);
 362
 363         if (!rfkill_epo_lock_active)
 364                 __rfkill_switch_all(type, blocked);
 365
 366         mutex_unlock(&rfkill_global_mutex);
 367 }
 368
 369 /**
 370  * rfkill_epo - emergency power off all transmitters
 371  *
 372  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 373  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 374  *
 375  * The global state before the EPO is saved and can be restored later
 376  * using rfkill_restore_states().
 377  */
 378 void rfkill_epo(void)
 379 {
 380         struct rfkill *rfkill;
 381         int i;
 382
 383         if (atomic_read(&rfkill_input_disabled))
 384                 return;
 385
 386         mutex_lock(&rfkill_global_mutex);
 387
 388         rfkill_epo_lock_active = true;
 389         list_for_each_entry(rfkill, &rfkill_list, node)
 390                 rfkill_set_block(rfkill, true);
 391
 392         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 393                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 394                 rfkill_global_states[i].cur = true;
 395         }
 396
 397         mutex_unlock(&rfkill_global_mutex);
 398 }
 399
 400 /**
 401  * rfkill_restore_states - restore global states
 402  *
 403  * Restore (and sync switches to) the global state from the
 404  * states in rfkill_default_states.  This can undo the effects of
 405  * a call to rfkill_epo().
 406  */
 407 void rfkill_restore_states(void)
 408 {
 409         int i;
 410
 411         if (atomic_read(&rfkill_input_disabled))
 412                 return;
 413
 414         mutex_lock(&rfkill_global_mutex);
 415
 416         rfkill_epo_lock_active = false;
 417         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 418                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 419         mutex_unlock(&rfkill_global_mutex);
 420 }
 421
 422 /**
 423  * rfkill_remove_epo_lock - unlock state changes
 424  *
 425  * Used by rfkill-input manually unlock state changes, when
 426  * the EPO switch is deactivated.
 427  */
 428 void rfkill_remove_epo_lock(void)
 429 {
 430         if (atomic_read(&rfkill_input_disabled))
 431                 return;
 432
 433         mutex_lock(&rfkill_global_mutex);
 434         rfkill_epo_lock_active = false;
 435         mutex_unlock(&rfkill_global_mutex);
 436 }
 437
 438 /**
 439  * rfkill_is_epo_lock_active - returns true EPO is active
 440  *
 441  * Returns 0 (false) if there is NOT an active EPO contidion,
 442  * and 1 (true) if there is an active EPO contition, which
 443  * locks all radios in one of the BLOCKED states.
 444  *
 445  * Can be called in atomic context.
 446  */
 447 bool rfkill_is_epo_lock_active(void)
 448 {
 449         return rfkill_epo_lock_active;
 450 }
 451
 452 /**
 453  * rfkill_get_global_sw_state - returns global state for a type
 454  * @type: the type to get the global state of
 455  *
 456  * Returns the current global state for a given wireless
 457  * device type.
 458  */
 459 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 460 {
 461         return rfkill_global_states[type].cur;
 462 }
 463 #endif
 464
 465
 466 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 467 {
 468         bool ret, change;
 469
 470         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 471
 472         if (!rfkill->registered)
 473                 return ret;
 474
 475         if (change)
 476                 schedule_work(&rfkill->uevent_work);
 477
 478         return ret;
 479 }
 480 EXPORT_SYMBOL(rfkill_set_hw_state);
 481
 482 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 483 {
 484         u32 bit = RFKILL_BLOCK_SW;
 485
 486         /* if in a ops->set_block right now, use other bit */
 487         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 488                 bit = RFKILL_BLOCK_SW_PREV;
 489
 490         if (blocked)
 491                 rfkill->state |= bit;
 492         else
 493                 rfkill->state &= ~bit;
 494 }
 495
 496 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 497 {
 498         unsigned long flags;
 499         bool prev, hwblock;
 500
 501         BUG_ON(!rfkill);
 502
 503         spin_lock_irqsave(&rfkill->lock, flags);
 504         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 505         __rfkill_set_sw_state(rfkill, blocked);
 506         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 507         blocked = blocked || hwblock;
 508         spin_unlock_irqrestore(&rfkill->lock, flags);
 509
 510         if (!rfkill->registered)
 511                 return blocked;
 512
 513         if (prev != blocked && !hwblock)
 514                 schedule_work(&rfkill->uevent_work);
 515
 516         rfkill_led_trigger_event(rfkill);
 517
 518         return blocked;
 519 }
 520 EXPORT_SYMBOL(rfkill_set_sw_state);
 521
 522 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 523 {
 524         unsigned long flags;
 525
 526         BUG_ON(!rfkill);
 527         BUG_ON(rfkill->registered);
 528
 529         spin_lock_irqsave(&rfkill->lock, flags);
 530         __rfkill_set_sw_state(rfkill, blocked);
 531         rfkill->persistent = true;
 532         spin_unlock_irqrestore(&rfkill->lock, flags);
 533 }
 534 EXPORT_SYMBOL(rfkill_init_sw_state);
 535
 536 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 537 {
 538         unsigned long flags;
 539         bool swprev, hwprev;
 540
 541         BUG_ON(!rfkill);
 542
 543         spin_lock_irqsave(&rfkill->lock, flags);
 544
 545         /*
 546          * No need to care about prev/setblock ... this is for uevent only
 547          * and that will get triggered by rfkill_set_block anyway.
 548          */
 549         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 550         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 551         __rfkill_set_sw_state(rfkill, sw);
 552         if (hw)
 553                 rfkill->state |= RFKILL_BLOCK_HW;
 554         else
 555                 rfkill->state &= ~RFKILL_BLOCK_HW;
 556
 557         spin_unlock_irqrestore(&rfkill->lock, flags);
 558
 559         if (!rfkill->registered) {
 560                 rfkill->persistent = true;
 561         } else {
 562                 if (swprev != sw || hwprev != hw)
 563                         schedule_work(&rfkill->uevent_work);
 564
 565                 rfkill_led_trigger_event(rfkill);
 566         }
 567 }
 568 EXPORT_SYMBOL(rfkill_set_states);
 569
 570 static ssize_t rfkill_name_show(struct device *dev,
 571                                 struct device_attribute *attr,
 572                                 char *buf)
 573 {
 574         struct rfkill *rfkill = to_rfkill(dev);
 575
 576         return sprintf(buf, "%s\n", rfkill->name);
 577 }
 578
 579 static const char *rfkill_get_type_str(enum rfkill_type type)
 580 {
 581         switch (type) {
 582         case RFKILL_TYPE_WLAN:
 583                 return "wlan";
 584         case RFKILL_TYPE_BLUETOOTH:
 585                 return "bluetooth";
 586         case RFKILL_TYPE_UWB:
 587                 return "ultrawideband";
 588         case RFKILL_TYPE_WIMAX:
 589                 return "wimax";
 590         case RFKILL_TYPE_WWAN:
 591                 return "wwan";
 592         case RFKILL_TYPE_GPS:
 593                 return "gps";
 594         default:
 595                 BUG();
 596         }
 597
 598         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_GPS + 1);
 599 }
 600
 601 static ssize_t rfkill_type_show(struct device *dev,
 602                                 struct device_attribute *attr,
 603                                 char *buf)
 604 {
 605         struct rfkill *rfkill = to_rfkill(dev);
 606
 607         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 608 }
 609
 610 static ssize_t rfkill_idx_show(struct device *dev,
 611                                struct device_attribute *attr,
 612                                char *buf)
 613 {
 614         struct rfkill *rfkill = to_rfkill(dev);
 615
 616         return sprintf(buf, "%d\n", rfkill->idx);
 617 }
 618
 619 static ssize_t rfkill_persistent_show(struct device *dev,
 620                                struct device_attribute *attr,
 621                                char *buf)
 622 {
 623         struct rfkill *rfkill = to_rfkill(dev);
 624
 625         return sprintf(buf, "%d\n", rfkill->persistent);
 626 }
 627
 628 static u8 user_state_from_blocked(unsigned long state)
 629 {
 630         if (state & RFKILL_BLOCK_HW)
 631                 return RFKILL_USER_STATE_HARD_BLOCKED;
 632         if (state & RFKILL_BLOCK_SW)
 633                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 634
 635         return RFKILL_USER_STATE_UNBLOCKED;
 636 }
 637
 638 static ssize_t rfkill_state_show(struct device *dev,
 639                                  struct device_attribute *attr,
 640                                  char *buf)
 641 {
 642         struct rfkill *rfkill = to_rfkill(dev);
 643         unsigned long flags;
 644         u32 state;
 645
 646         spin_lock_irqsave(&rfkill->lock, flags);
 647         state = rfkill->state;
 648         spin_unlock_irqrestore(&rfkill->lock, flags);
 649
 650         return sprintf(buf, "%d\n", user_state_from_blocked(state));
 651 }
 652
 653 static ssize_t rfkill_state_store(struct device *dev,
 654                                   struct device_attribute *attr,
 655                                   const char *buf, size_t count)
 656 {
 657         struct rfkill *rfkill = to_rfkill(dev);
 658         unsigned long state;
 659         int err;
 660
 661         if (!capable(CAP_NET_ADMIN))
 662                 return -EPERM;
 663
 664         err = strict_strtoul(buf, 0, &state);
 665         if (err)
 666                 return err;
 667
 668         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 669             state != RFKILL_USER_STATE_UNBLOCKED)
 670                 return -EINVAL;
 671
 672         mutex_lock(&rfkill_global_mutex);
 673         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 674         mutex_unlock(&rfkill_global_mutex);
 675
 676         return err ?: count;
 677 }
 678
 679 static ssize_t rfkill_claim_show(struct device *dev,
 680                                  struct device_attribute *attr,
 681                                  char *buf)
 682 {
 683         return sprintf(buf, "%d\n", 0);
 684 }
 685
 686 static ssize_t rfkill_claim_store(struct device *dev,
 687                                   struct device_attribute *attr,
 688                                   const char *buf, size_t count)
 689 {
 690         return -EOPNOTSUPP;
 691 }
 692
 693 static struct device_attribute rfkill_dev_attrs[] = {
 694         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 695         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 696         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
 697         __ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
 698         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 699         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 700         __ATTR_NULL
 701 };
 702
 703 static void rfkill_release(struct device *dev)
 704 {
 705         struct rfkill *rfkill = to_rfkill(dev);
 706
 707         kfree(rfkill);
 708 }
 709
 710 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 711 {
 712         struct rfkill *rfkill = to_rfkill(dev);
 713         unsigned long flags;
 714         u32 state;
 715         int error;
 716
 717         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 718         if (error)
 719                 return error;
 720         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 721                                rfkill_get_type_str(rfkill->type));
 722         if (error)
 723                 return error;
 724         spin_lock_irqsave(&rfkill->lock, flags);
 725         state = rfkill->state;
 726         spin_unlock_irqrestore(&rfkill->lock, flags);
 727         error = add_uevent_var(env, "RFKILL_STATE=%d",
 728                                user_state_from_blocked(state));
 729         return error;
 730 }
 731
 732 void rfkill_pause_polling(struct rfkill *rfkill)
 733 {
 734         BUG_ON(!rfkill);
 735
 736         if (!rfkill->ops->poll)
 737                 return;
 738
 739         cancel_delayed_work_sync(&rfkill->poll_work);
 740 }
 741 EXPORT_SYMBOL(rfkill_pause_polling);
 742
 743 void rfkill_resume_polling(struct rfkill *rfkill)
 744 {
 745         BUG_ON(!rfkill);
 746
 747         if (!rfkill->ops->poll)
 748                 return;
 749
 750         schedule_work(&rfkill->poll_work.work);
 751 }
 752 EXPORT_SYMBOL(rfkill_resume_polling);
 753
 754 static int rfkill_suspend(struct device *dev, pm_message_t state)
 755 {
 756         struct rfkill *rfkill = to_rfkill(dev);
 757
 758         rfkill_pause_polling(rfkill);
 759
 760         return 0;
 761 }
 762
 763 static int rfkill_resume(struct device *dev)
 764 {
 765         struct rfkill *rfkill = to_rfkill(dev);
 766         bool cur;
 767
 768         if (!rfkill->persistent) {
 769                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 770                 rfkill_set_block(rfkill, cur);
 771         }
 772
 773         rfkill_resume_polling(rfkill);
 774
 775         return 0;
 776 }
 777
 778 static struct class rfkill_class = {
 779         .name           = "rfkill",
 780         .dev_release    = rfkill_release,
 781         .dev_attrs      = rfkill_dev_attrs,
 782         .dev_uevent     = rfkill_dev_uevent,
 783         .suspend        = rfkill_suspend,
 784         .resume         = rfkill_resume,
 785 };
 786
 787 bool rfkill_blocked(struct rfkill *rfkill)
 788 {
 789         unsigned long flags;
 790         u32 state;
 791
 792         spin_lock_irqsave(&rfkill->lock, flags);
 793         state = rfkill->state;
 794         spin_unlock_irqrestore(&rfkill->lock, flags);
 795
 796         return !!(state & RFKILL_BLOCK_ANY);
 797 }
 798 EXPORT_SYMBOL(rfkill_blocked);
 799
 800
 801 struct rfkill * __must_check rfkill_alloc(const char *name,
 802                                           struct device *parent,
 803                                           const enum rfkill_type type,
 804                                           const struct rfkill_ops *ops,
 805                                           void *ops_data)
 806 {
 807         struct rfkill *rfkill;
 808         struct device *dev;
 809
 810         if (WARN_ON(!ops))
 811                 return NULL;
 812
 813         if (WARN_ON(!ops->set_block))
 814                 return NULL;
 815
 816         if (WARN_ON(!name))
 817                 return NULL;
 818
 819         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 820                 return NULL;
 821
 822         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 823         if (!rfkill)
 824                 return NULL;
 825
 826         spin_lock_init(&rfkill->lock);
 827         INIT_LIST_HEAD(&rfkill->node);
 828         rfkill->type = type;
 829         rfkill->name = name;
 830         rfkill->ops = ops;
 831         rfkill->data = ops_data;
 832
 833         dev = &rfkill->dev;
 834         dev->class = &rfkill_class;
 835         dev->parent = parent;
 836         device_initialize(dev);
 837
 838         return rfkill;
 839 }
 840 EXPORT_SYMBOL(rfkill_alloc);
 841
 842 static void rfkill_poll(struct work_struct *work)
 843 {
 844         struct rfkill *rfkill;
 845
 846         rfkill = container_of(work, struct rfkill, poll_work.work);
 847
 848         /*
 849          * Poll hardware state -- driver will use one of the
 850          * rfkill_set{,_hw,_sw}_state functions and use its
 851          * return value to update the current status.
 852          */
 853         rfkill->ops->poll(rfkill, rfkill->data);
 854
 855         schedule_delayed_work(&rfkill->poll_work,
 856                 round_jiffies_relative(POLL_INTERVAL));
 857 }
 858
 859 static void rfkill_uevent_work(struct work_struct *work)
 860 {
 861         struct rfkill *rfkill;
 862
 863         rfkill = container_of(work, struct rfkill, uevent_work);
 864
 865         mutex_lock(&rfkill_global_mutex);
 866         rfkill_event(rfkill);
 867         mutex_unlock(&rfkill_global_mutex);
 868 }
 869
 870 static void rfkill_sync_work(struct work_struct *work)
 871 {
 872         struct rfkill *rfkill;
 873         bool cur;
 874
 875         rfkill = container_of(work, struct rfkill, sync_work);
 876
 877         mutex_lock(&rfkill_global_mutex);
 878         cur = rfkill_global_states[rfkill->type].cur;
 879         rfkill_set_block(rfkill, cur);
 880         mutex_unlock(&rfkill_global_mutex);
 881 }
 882
 883 int __must_check rfkill_register(struct rfkill *rfkill)
 884 {
 885         static unsigned long rfkill_no;
 886         struct device *dev = &rfkill->dev;
 887         int error;
 888
 889         BUG_ON(!rfkill);
 890
 891         mutex_lock(&rfkill_global_mutex);
 892
 893         if (rfkill->registered) {
 894                 error = -EALREADY;
 895                 goto unlock;
 896         }
 897
 898         rfkill->idx = rfkill_no;
 899         dev_set_name(dev, "rfkill%lu", rfkill_no);
 900         rfkill_no++;
 901
 902         list_add_tail(&rfkill->node, &rfkill_list);
 903
 904         error = device_add(dev);
 905         if (error)
 906                 goto remove;
 907
 908         error = rfkill_led_trigger_register(rfkill);
 909         if (error)
 910                 goto devdel;
 911
 912         rfkill->registered = true;
 913
 914         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 915         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 916         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 917
 918         if (rfkill->ops->poll)
 919                 schedule_delayed_work(&rfkill->poll_work,
 920                         round_jiffies_relative(POLL_INTERVAL));
 921
 922         if (!rfkill->persistent || rfkill_epo_lock_active) {
 923                 schedule_work(&rfkill->sync_work);
 924         } else {
 925 #ifdef CONFIG_RFKILL_INPUT
 926                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 927
 928                 if (!atomic_read(&rfkill_input_disabled))
 929                         __rfkill_switch_all(rfkill->type, soft_blocked);
 930 #endif
 931         }
 932
 933         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 934
 935         mutex_unlock(&rfkill_global_mutex);
 936         return 0;
 937
 938  devdel:
 939         device_del(&rfkill->dev);
 940  remove:
 941         list_del_init(&rfkill->node);
 942  unlock:
 943         mutex_unlock(&rfkill_global_mutex);
 944         return error;
 945 }
 946 EXPORT_SYMBOL(rfkill_register);
 947
 948 void rfkill_unregister(struct rfkill *rfkill)
 949 {
 950         BUG_ON(!rfkill);
 951
 952         if (rfkill->ops->poll)
 953                 cancel_delayed_work_sync(&rfkill->poll_work);
 954
 955         cancel_work_sync(&rfkill->uevent_work);
 956         cancel_work_sync(&rfkill->sync_work);
 957
 958         rfkill->registered = false;
 959
 960         device_del(&rfkill->dev);
 961
 962         mutex_lock(&rfkill_global_mutex);
 963         rfkill_send_events(rfkill, RFKILL_OP_DEL);
 964         list_del_init(&rfkill->node);
 965         mutex_unlock(&rfkill_global_mutex);
 966
 967         rfkill_led_trigger_unregister(rfkill);
 968 }
 969 EXPORT_SYMBOL(rfkill_unregister);
 970
 971 void rfkill_destroy(struct rfkill *rfkill)
 972 {
 973         if (rfkill)
 974                 put_device(&rfkill->dev);
 975 }
 976 EXPORT_SYMBOL(rfkill_destroy);
 977
 978 static int rfkill_fop_open(struct inode *inode, struct file *file)
 979 {
 980         struct rfkill_data *data;
 981         struct rfkill *rfkill;
 982         struct rfkill_int_event *ev, *tmp;
 983
 984         data = kzalloc(sizeof(*data), GFP_KERNEL);
 985         if (!data)
 986                 return -ENOMEM;
 987
 988         INIT_LIST_HEAD(&data->events);
 989         mutex_init(&data->mtx);
 990         init_waitqueue_head(&data->read_wait);
 991
 992         mutex_lock(&rfkill_global_mutex);
 993         mutex_lock(&data->mtx);
 994         /*
 995          * start getting events from elsewhere but hold mtx to get
 996          * startup events added first
 997          */
 998         list_add(&data->list, &rfkill_fds);
 999
1000         list_for_each_entry(rfkill, &rfkill_list, node) {
1001                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1002                 if (!ev)
1003                         goto free;
1004                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1005                 list_add_tail(&ev->list, &data->events);
1006         }
1007         mutex_unlock(&data->mtx);
1008         mutex_unlock(&rfkill_global_mutex);
1009
1010         file->private_data = data;
1011
1012         return nonseekable_open(inode, file);
1013
1014  free:
1015         mutex_unlock(&data->mtx);
1016         mutex_unlock(&rfkill_global_mutex);
1017         mutex_destroy(&data->mtx);
1018         list_for_each_entry_safe(ev, tmp, &data->events, list)
1019                 kfree(ev);
1020         kfree(data);
1021         return -ENOMEM;
1022 }
1023
1024 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1025 {
1026         struct rfkill_data *data = file->private_data;
1027         unsigned int res = POLLOUT | POLLWRNORM;
1028
1029         poll_wait(file, &data->read_wait, wait);
1030
1031         mutex_lock(&data->mtx);
1032         if (!list_empty(&data->events))
1033                 res = POLLIN | POLLRDNORM;
1034         mutex_unlock(&data->mtx);
1035
1036         return res;
1037 }
1038
1039 static bool rfkill_readable(struct rfkill_data *data)
1040 {
1041         bool r;
1042
1043         mutex_lock(&data->mtx);
1044         r = !list_empty(&data->events);
1045         mutex_unlock(&data->mtx);
1046
1047         return r;
1048 }
1049
1050 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1051                                size_t count, loff_t *pos)
1052 {
1053         struct rfkill_data *data = file->private_data;
1054         struct rfkill_int_event *ev;
1055         unsigned long sz;
1056         int ret;
1057
1058         mutex_lock(&data->mtx);
1059
1060         while (list_empty(&data->events)) {
1061                 if (file->f_flags & O_NONBLOCK) {
1062                         ret = -EAGAIN;
1063                         goto out;
1064                 }
1065                 mutex_unlock(&data->mtx);
1066                 ret = wait_event_interruptible(data->read_wait,
1067                                                rfkill_readable(data));
1068                 mutex_lock(&data->mtx);
1069
1070                 if (ret)
1071                         goto out;
1072         }
1073
1074         ev = list_first_entry(&data->events, struct rfkill_int_event,
1075                                 list);
1076
1077         sz = min_t(unsigned long, sizeof(ev->ev), count);
1078         ret = sz;
1079         if (copy_to_user(buf, &ev->ev, sz))
1080                 ret = -EFAULT;
1081
1082         list_del(&ev->list);
1083         kfree(ev);
1084  out:
1085         mutex_unlock(&data->mtx);
1086         return ret;
1087 }
1088
1089 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1090                                 size_t count, loff_t *pos)
1091 {
1092         struct rfkill *rfkill;
1093         struct rfkill_event ev;
1094
1095         /* we don't need the 'hard' variable but accept it */
1096         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1097                 return -EINVAL;
1098
1099         /*
1100          * Copy as much data as we can accept into our 'ev' buffer,
1101          * but tell userspace how much we've copied so it can determine
1102          * our API version even in a write() call, if it cares.
1103          */
1104         count = min(count, sizeof(ev));
1105         if (copy_from_user(&ev, buf, count))
1106                 return -EFAULT;
1107
1108         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1109                 return -EINVAL;
1110
1111         if (ev.type >= NUM_RFKILL_TYPES)
1112                 return -EINVAL;
1113
1114         mutex_lock(&rfkill_global_mutex);
1115
1116         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1117                 if (ev.type == RFKILL_TYPE_ALL) {
1118                         enum rfkill_type i;
1119                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1120                                 rfkill_global_states[i].cur = ev.soft;
1121                 } else {
1122                         rfkill_global_states[ev.type].cur = ev.soft;
1123                 }
1124         }
1125
1126         list_for_each_entry(rfkill, &rfkill_list, node) {
1127                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1128                         continue;
1129
1130                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1131                         continue;
1132
1133                 rfkill_set_block(rfkill, ev.soft);
1134         }
1135         mutex_unlock(&rfkill_global_mutex);
1136
1137         return count;
1138 }
1139
1140 static int rfkill_fop_release(struct inode *inode, struct file *file)
1141 {
1142         struct rfkill_data *data = file->private_data;
1143         struct rfkill_int_event *ev, *tmp;
1144
1145         mutex_lock(&rfkill_global_mutex);
1146         list_del(&data->list);
1147         mutex_unlock(&rfkill_global_mutex);
1148
1149         mutex_destroy(&data->mtx);
1150         list_for_each_entry_safe(ev, tmp, &data->events, list)
1151                 kfree(ev);
1152
1153 #ifdef CONFIG_RFKILL_INPUT
1154         if (data->input_handler)
1155                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1156                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1157 #endif
1158
1159         kfree(data);
1160
1161         return 0;
1162 }
1163
1164 #ifdef CONFIG_RFKILL_INPUT
1165 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1166                              unsigned long arg)
1167 {
1168         struct rfkill_data *data = file->private_data;
1169
1170         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1171                 return -ENOSYS;
1172
1173         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1174                 return -ENOSYS;
1175
1176         mutex_lock(&data->mtx);
1177
1178         if (!data->input_handler) {
1179                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1180                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1181                 data->input_handler = true;
1182         }
1183
1184         mutex_unlock(&data->mtx);
1185
1186         return 0;
1187 }
1188 #endif
1189
1190 static const struct file_operations rfkill_fops = {
1191         .open           = rfkill_fop_open,
1192         .read           = rfkill_fop_read,
1193         .write          = rfkill_fop_write,
1194         .poll           = rfkill_fop_poll,
1195         .release        = rfkill_fop_release,
1196 #ifdef CONFIG_RFKILL_INPUT
1197         .unlocked_ioctl = rfkill_fop_ioctl,
1198         .compat_ioctl   = rfkill_fop_ioctl,
1199 #endif
1200 };
1201
1202 static struct miscdevice rfkill_miscdev = {
1203         .name   = "rfkill",
1204         .fops   = &rfkill_fops,
1205         .minor  = MISC_DYNAMIC_MINOR,
1206 };
1207
1208 static int __init rfkill_init(void)
1209 {
1210         int error;
1211         int i;
1212
1213         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1214                 rfkill_global_states[i].cur = !rfkill_default_state;
1215
1216         error = class_register(&rfkill_class);
1217         if (error)
1218                 goto out;
1219
1220         error = misc_register(&rfkill_miscdev);
1221         if (error) {
1222                 class_unregister(&rfkill_class);
1223                 goto out;
1224         }
1225
1226 #ifdef CONFIG_RFKILL_INPUT
1227         error = rfkill_handler_init();
1228         if (error) {
1229                 misc_deregister(&rfkill_miscdev);
1230                 class_unregister(&rfkill_class);
1231                 goto out;
1232         }
1233 #endif
1234
1235  out:
1236         return error;
1237 }
1238 subsys_initcall(rfkill_init);
1239
1240 static void __exit rfkill_exit(void)
1241 {
1242 #ifdef CONFIG_RFKILL_INPUT
1243         rfkill_handler_exit();
1244 #endif
1245         misc_deregister(&rfkill_miscdev);
1246         class_unregister(&rfkill_class);
1247 }
1248 module_exit(rfkill_exit);