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