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, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/capability.h>
  25 #include <linux/list.h>
  26 #include <linux/mutex.h>
  27 #include <linux/rfkill.h>
  28 #include <linux/sched.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/device.h>
  31 #include <linux/miscdevice.h>
  32 #include <linux/wait.h>
  33 #include <linux/poll.h>
  34 #include <linux/fs.h>
  35 #include <linux/slab.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         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         char                    name[];
  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         bool prev, curr;
 272         int err;
 273
 274         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 275                 return;
 276
 277         /*
 278          * Some platforms (...!) generate input events which affect the
 279          * _hard_ kill state -- whenever something tries to change the
 280          * current software state query the hardware state too.
 281          */
 282         if (rfkill->ops->query)
 283                 rfkill->ops->query(rfkill, rfkill->data);
 284
 285         spin_lock_irqsave(&rfkill->lock, flags);
 286         prev = rfkill->state & RFKILL_BLOCK_SW;
 287
 288         if (rfkill->state & RFKILL_BLOCK_SW)
 289                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 290         else
 291                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 292
 293         if (blocked)
 294                 rfkill->state |= RFKILL_BLOCK_SW;
 295         else
 296                 rfkill->state &= ~RFKILL_BLOCK_SW;
 297
 298         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 299         spin_unlock_irqrestore(&rfkill->lock, flags);
 300
 301         err = rfkill->ops->set_block(rfkill->data, blocked);
 302
 303         spin_lock_irqsave(&rfkill->lock, flags);
 304         if (err) {
 305                 /*
 306                  * Failed -- reset status to _prev, this may be different
 307                  * from what set set _PREV to earlier in this function
 308                  * if rfkill_set_sw_state was invoked.
 309                  */
 310                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 311                         rfkill->state |= RFKILL_BLOCK_SW;
 312                 else
 313                         rfkill->state &= ~RFKILL_BLOCK_SW;
 314         }
 315         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 316         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 317         curr = rfkill->state & RFKILL_BLOCK_SW;
 318         spin_unlock_irqrestore(&rfkill->lock, flags);
 319
 320         rfkill_led_trigger_event(rfkill);
 321
 322         if (prev != curr)
 323                 rfkill_event(rfkill);
 324 }
 325
 326 #ifdef CONFIG_RFKILL_INPUT
 327 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 328
 329 /**
 330  * __rfkill_switch_all - Toggle state of all switches of given type
 331  * @type: type of interfaces to be affected
 332  * @blocked: the new state
 333  *
 334  * This function sets the state of all switches of given type,
 335  * unless a specific switch is claimed by userspace (in which case,
 336  * that switch is left alone) or suspended.
 337  *
 338  * Caller must have acquired rfkill_global_mutex.
 339  */
 340 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 341 {
 342         struct rfkill *rfkill;
 343
 344         if (type == RFKILL_TYPE_ALL) {
 345                 int i;
 346
 347                 for (i = 0; i < NUM_RFKILL_TYPES; i++)
 348                         rfkill_global_states[i].cur = blocked;
 349         } else {
 350                 rfkill_global_states[type].cur = blocked;
 351         }
 352
 353         list_for_each_entry(rfkill, &rfkill_list, node) {
 354                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 355                         continue;
 356
 357                 rfkill_set_block(rfkill, blocked);
 358         }
 359 }
 360
 361 /**
 362  * rfkill_switch_all - Toggle state of all switches of given type
 363  * @type: type of interfaces to be affected
 364  * @blocked: the new state
 365  *
 366  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 367  * Please refer to __rfkill_switch_all() for details.
 368  *
 369  * Does nothing if the EPO lock is active.
 370  */
 371 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 372 {
 373         if (atomic_read(&rfkill_input_disabled))
 374                 return;
 375
 376         mutex_lock(&rfkill_global_mutex);
 377
 378         if (!rfkill_epo_lock_active)
 379                 __rfkill_switch_all(type, blocked);
 380
 381         mutex_unlock(&rfkill_global_mutex);
 382 }
 383
 384 /**
 385  * rfkill_epo - emergency power off all transmitters
 386  *
 387  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 388  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 389  *
 390  * The global state before the EPO is saved and can be restored later
 391  * using rfkill_restore_states().
 392  */
 393 void rfkill_epo(void)
 394 {
 395         struct rfkill *rfkill;
 396         int i;
 397
 398         if (atomic_read(&rfkill_input_disabled))
 399                 return;
 400
 401         mutex_lock(&rfkill_global_mutex);
 402
 403         rfkill_epo_lock_active = true;
 404         list_for_each_entry(rfkill, &rfkill_list, node)
 405                 rfkill_set_block(rfkill, true);
 406
 407         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 408                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 409                 rfkill_global_states[i].cur = true;
 410         }
 411
 412         mutex_unlock(&rfkill_global_mutex);
 413 }
 414
 415 /**
 416  * rfkill_restore_states - restore global states
 417  *
 418  * Restore (and sync switches to) the global state from the
 419  * states in rfkill_default_states.  This can undo the effects of
 420  * a call to rfkill_epo().
 421  */
 422 void rfkill_restore_states(void)
 423 {
 424         int i;
 425
 426         if (atomic_read(&rfkill_input_disabled))
 427                 return;
 428
 429         mutex_lock(&rfkill_global_mutex);
 430
 431         rfkill_epo_lock_active = false;
 432         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 433                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 434         mutex_unlock(&rfkill_global_mutex);
 435 }
 436
 437 /**
 438  * rfkill_remove_epo_lock - unlock state changes
 439  *
 440  * Used by rfkill-input manually unlock state changes, when
 441  * the EPO switch is deactivated.
 442  */
 443 void rfkill_remove_epo_lock(void)
 444 {
 445         if (atomic_read(&rfkill_input_disabled))
 446                 return;
 447
 448         mutex_lock(&rfkill_global_mutex);
 449         rfkill_epo_lock_active = false;
 450         mutex_unlock(&rfkill_global_mutex);
 451 }
 452
 453 /**
 454  * rfkill_is_epo_lock_active - returns true EPO is active
 455  *
 456  * Returns 0 (false) if there is NOT an active EPO contidion,
 457  * and 1 (true) if there is an active EPO contition, which
 458  * locks all radios in one of the BLOCKED states.
 459  *
 460  * Can be called in atomic context.
 461  */
 462 bool rfkill_is_epo_lock_active(void)
 463 {
 464         return rfkill_epo_lock_active;
 465 }
 466
 467 /**
 468  * rfkill_get_global_sw_state - returns global state for a type
 469  * @type: the type to get the global state of
 470  *
 471  * Returns the current global state for a given wireless
 472  * device type.
 473  */
 474 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 475 {
 476         return rfkill_global_states[type].cur;
 477 }
 478 #endif
 479
 480
 481 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 482 {
 483         bool ret, change;
 484
 485         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 486
 487         if (!rfkill->registered)
 488                 return ret;
 489
 490         if (change)
 491                 schedule_work(&rfkill->uevent_work);
 492
 493         return ret;
 494 }
 495 EXPORT_SYMBOL(rfkill_set_hw_state);
 496
 497 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 498 {
 499         u32 bit = RFKILL_BLOCK_SW;
 500
 501         /* if in a ops->set_block right now, use other bit */
 502         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 503                 bit = RFKILL_BLOCK_SW_PREV;
 504
 505         if (blocked)
 506                 rfkill->state |= bit;
 507         else
 508                 rfkill->state &= ~bit;
 509 }
 510
 511 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 512 {
 513         unsigned long flags;
 514         bool prev, hwblock;
 515
 516         BUG_ON(!rfkill);
 517
 518         spin_lock_irqsave(&rfkill->lock, flags);
 519         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 520         __rfkill_set_sw_state(rfkill, blocked);
 521         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 522         blocked = blocked || hwblock;
 523         spin_unlock_irqrestore(&rfkill->lock, flags);
 524
 525         if (!rfkill->registered)
 526                 return blocked;
 527
 528         if (prev != blocked && !hwblock)
 529                 schedule_work(&rfkill->uevent_work);
 530
 531         rfkill_led_trigger_event(rfkill);
 532
 533         return blocked;
 534 }
 535 EXPORT_SYMBOL(rfkill_set_sw_state);
 536
 537 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 538 {
 539         unsigned long flags;
 540
 541         BUG_ON(!rfkill);
 542         BUG_ON(rfkill->registered);
 543
 544         spin_lock_irqsave(&rfkill->lock, flags);
 545         __rfkill_set_sw_state(rfkill, blocked);
 546         rfkill->persistent = true;
 547         spin_unlock_irqrestore(&rfkill->lock, flags);
 548 }
 549 EXPORT_SYMBOL(rfkill_init_sw_state);
 550
 551 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 552 {
 553         unsigned long flags;
 554         bool swprev, hwprev;
 555
 556         BUG_ON(!rfkill);
 557
 558         spin_lock_irqsave(&rfkill->lock, flags);
 559
 560         /*
 561          * No need to care about prev/setblock ... this is for uevent only
 562          * and that will get triggered by rfkill_set_block anyway.
 563          */
 564         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 565         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 566         __rfkill_set_sw_state(rfkill, sw);
 567         if (hw)
 568                 rfkill->state |= RFKILL_BLOCK_HW;
 569         else
 570                 rfkill->state &= ~RFKILL_BLOCK_HW;
 571
 572         spin_unlock_irqrestore(&rfkill->lock, flags);
 573
 574         if (!rfkill->registered) {
 575                 rfkill->persistent = true;
 576         } else {
 577                 if (swprev != sw || hwprev != hw)
 578                         schedule_work(&rfkill->uevent_work);
 579
 580                 rfkill_led_trigger_event(rfkill);
 581         }
 582 }
 583 EXPORT_SYMBOL(rfkill_set_states);
 584
 585 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 586                          char *buf)
 587 {
 588         struct rfkill *rfkill = to_rfkill(dev);
 589
 590         return sprintf(buf, "%s\n", rfkill->name);
 591 }
 592 static DEVICE_ATTR_RO(name);
 593
 594 static const char *rfkill_get_type_str(enum rfkill_type type)
 595 {
 596         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_NFC + 1);
 597
 598         switch (type) {
 599         case RFKILL_TYPE_WLAN:
 600                 return "wlan";
 601         case RFKILL_TYPE_BLUETOOTH:
 602                 return "bluetooth";
 603         case RFKILL_TYPE_UWB:
 604                 return "ultrawideband";
 605         case RFKILL_TYPE_WIMAX:
 606                 return "wimax";
 607         case RFKILL_TYPE_WWAN:
 608                 return "wwan";
 609         case RFKILL_TYPE_GPS:
 610                 return "gps";
 611         case RFKILL_TYPE_FM:
 612                 return "fm";
 613         case RFKILL_TYPE_NFC:
 614                 return "nfc";
 615         default:
 616                 BUG();
 617         }
 618 }
 619
 620 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 621                          char *buf)
 622 {
 623         struct rfkill *rfkill = to_rfkill(dev);
 624
 625         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 626 }
 627 static DEVICE_ATTR_RO(type);
 628
 629 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 630                           char *buf)
 631 {
 632         struct rfkill *rfkill = to_rfkill(dev);
 633
 634         return sprintf(buf, "%d\n", rfkill->idx);
 635 }
 636 static DEVICE_ATTR_RO(index);
 637
 638 static ssize_t persistent_show(struct device *dev,
 639                                struct device_attribute *attr, char *buf)
 640 {
 641         struct rfkill *rfkill = to_rfkill(dev);
 642
 643         return sprintf(buf, "%d\n", rfkill->persistent);
 644 }
 645 static DEVICE_ATTR_RO(persistent);
 646
 647 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 648                          char *buf)
 649 {
 650         struct rfkill *rfkill = to_rfkill(dev);
 651
 652         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 653 }
 654 static DEVICE_ATTR_RO(hard);
 655
 656 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 657                          char *buf)
 658 {
 659         struct rfkill *rfkill = to_rfkill(dev);
 660
 661         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 662 }
 663
 664 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 665                           const char *buf, size_t count)
 666 {
 667         struct rfkill *rfkill = to_rfkill(dev);
 668         unsigned long state;
 669         int err;
 670
 671         if (!capable(CAP_NET_ADMIN))
 672                 return -EPERM;
 673
 674         err = kstrtoul(buf, 0, &state);
 675         if (err)
 676                 return err;
 677
 678         if (state > 1 )
 679                 return -EINVAL;
 680
 681         mutex_lock(&rfkill_global_mutex);
 682         rfkill_set_block(rfkill, state);
 683         mutex_unlock(&rfkill_global_mutex);
 684
 685         return count;
 686 }
 687 static DEVICE_ATTR_RW(soft);
 688
 689 static u8 user_state_from_blocked(unsigned long state)
 690 {
 691         if (state & RFKILL_BLOCK_HW)
 692                 return RFKILL_USER_STATE_HARD_BLOCKED;
 693         if (state & RFKILL_BLOCK_SW)
 694                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 695
 696         return RFKILL_USER_STATE_UNBLOCKED;
 697 }
 698
 699 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 700                           char *buf)
 701 {
 702         struct rfkill *rfkill = to_rfkill(dev);
 703
 704         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 705 }
 706
 707 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 708                            const char *buf, size_t count)
 709 {
 710         struct rfkill *rfkill = to_rfkill(dev);
 711         unsigned long state;
 712         int err;
 713
 714         if (!capable(CAP_NET_ADMIN))
 715                 return -EPERM;
 716
 717         err = kstrtoul(buf, 0, &state);
 718         if (err)
 719                 return err;
 720
 721         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 722             state != RFKILL_USER_STATE_UNBLOCKED)
 723                 return -EINVAL;
 724
 725         mutex_lock(&rfkill_global_mutex);
 726         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 727         mutex_unlock(&rfkill_global_mutex);
 728
 729         return count;
 730 }
 731 static DEVICE_ATTR_RW(state);
 732
 733 static ssize_t claim_show(struct device *dev, struct device_attribute *attr,
 734                           char *buf)
 735 {
 736         return sprintf(buf, "%d\n", 0);
 737 }
 738 static DEVICE_ATTR_RO(claim);
 739
 740 static struct attribute *rfkill_dev_attrs[] = {
 741         &dev_attr_name.attr,
 742         &dev_attr_type.attr,
 743         &dev_attr_index.attr,
 744         &dev_attr_persistent.attr,
 745         &dev_attr_state.attr,
 746         &dev_attr_claim.attr,
 747         &dev_attr_soft.attr,
 748         &dev_attr_hard.attr,
 749         NULL,
 750 };
 751 ATTRIBUTE_GROUPS(rfkill_dev);
 752
 753 static void rfkill_release(struct device *dev)
 754 {
 755         struct rfkill *rfkill = to_rfkill(dev);
 756
 757         kfree(rfkill);
 758 }
 759
 760 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 761 {
 762         struct rfkill *rfkill = to_rfkill(dev);
 763         unsigned long flags;
 764         u32 state;
 765         int error;
 766
 767         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 768         if (error)
 769                 return error;
 770         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 771                                rfkill_get_type_str(rfkill->type));
 772         if (error)
 773                 return error;
 774         spin_lock_irqsave(&rfkill->lock, flags);
 775         state = rfkill->state;
 776         spin_unlock_irqrestore(&rfkill->lock, flags);
 777         error = add_uevent_var(env, "RFKILL_STATE=%d",
 778                                user_state_from_blocked(state));
 779         return error;
 780 }
 781
 782 void rfkill_pause_polling(struct rfkill *rfkill)
 783 {
 784         BUG_ON(!rfkill);
 785
 786         if (!rfkill->ops->poll)
 787                 return;
 788
 789         cancel_delayed_work_sync(&rfkill->poll_work);
 790 }
 791 EXPORT_SYMBOL(rfkill_pause_polling);
 792
 793 void rfkill_resume_polling(struct rfkill *rfkill)
 794 {
 795         BUG_ON(!rfkill);
 796
 797         if (!rfkill->ops->poll)
 798                 return;
 799
 800         queue_delayed_work(system_power_efficient_wq,
 801                            &rfkill->poll_work, 0);
 802 }
 803 EXPORT_SYMBOL(rfkill_resume_polling);
 804
 805 #ifdef CONFIG_PM_SLEEP
 806 static int rfkill_suspend(struct device *dev)
 807 {
 808         struct rfkill *rfkill = to_rfkill(dev);
 809
 810         rfkill_pause_polling(rfkill);
 811
 812         return 0;
 813 }
 814
 815 static int rfkill_resume(struct device *dev)
 816 {
 817         struct rfkill *rfkill = to_rfkill(dev);
 818         bool cur;
 819
 820         if (!rfkill->persistent) {
 821                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 822                 rfkill_set_block(rfkill, cur);
 823         }
 824
 825         rfkill_resume_polling(rfkill);
 826
 827         return 0;
 828 }
 829
 830 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 831 #define RFKILL_PM_OPS (&rfkill_pm_ops)
 832 #else
 833 #define RFKILL_PM_OPS NULL
 834 #endif
 835
 836 static struct class rfkill_class = {
 837         .name           = "rfkill",
 838         .dev_release    = rfkill_release,
 839         .dev_groups     = rfkill_dev_groups,
 840         .dev_uevent     = rfkill_dev_uevent,
 841         .pm             = RFKILL_PM_OPS,
 842 };
 843
 844 bool rfkill_blocked(struct rfkill *rfkill)
 845 {
 846         unsigned long flags;
 847         u32 state;
 848
 849         spin_lock_irqsave(&rfkill->lock, flags);
 850         state = rfkill->state;
 851         spin_unlock_irqrestore(&rfkill->lock, flags);
 852
 853         return !!(state & RFKILL_BLOCK_ANY);
 854 }
 855 EXPORT_SYMBOL(rfkill_blocked);
 856
 857
 858 struct rfkill * __must_check rfkill_alloc(const char *name,
 859                                           struct device *parent,
 860                                           const enum rfkill_type type,
 861                                           const struct rfkill_ops *ops,
 862                                           void *ops_data)
 863 {
 864         struct rfkill *rfkill;
 865         struct device *dev;
 866
 867         if (WARN_ON(!ops))
 868                 return NULL;
 869
 870         if (WARN_ON(!ops->set_block))
 871                 return NULL;
 872
 873         if (WARN_ON(!name))
 874                 return NULL;
 875
 876         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 877                 return NULL;
 878
 879         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 880         if (!rfkill)
 881                 return NULL;
 882
 883         spin_lock_init(&rfkill->lock);
 884         INIT_LIST_HEAD(&rfkill->node);
 885         rfkill->type = type;
 886         strcpy(rfkill->name, name);
 887         rfkill->ops = ops;
 888         rfkill->data = ops_data;
 889
 890         dev = &rfkill->dev;
 891         dev->class = &rfkill_class;
 892         dev->parent = parent;
 893         device_initialize(dev);
 894
 895         return rfkill;
 896 }
 897 EXPORT_SYMBOL(rfkill_alloc);
 898
 899 static void rfkill_poll(struct work_struct *work)
 900 {
 901         struct rfkill *rfkill;
 902
 903         rfkill = container_of(work, struct rfkill, poll_work.work);
 904
 905         /*
 906          * Poll hardware state -- driver will use one of the
 907          * rfkill_set{,_hw,_sw}_state functions and use its
 908          * return value to update the current status.
 909          */
 910         rfkill->ops->poll(rfkill, rfkill->data);
 911
 912         queue_delayed_work(system_power_efficient_wq,
 913                 &rfkill->poll_work,
 914                 round_jiffies_relative(POLL_INTERVAL));
 915 }
 916
 917 static void rfkill_uevent_work(struct work_struct *work)
 918 {
 919         struct rfkill *rfkill;
 920
 921         rfkill = container_of(work, struct rfkill, uevent_work);
 922
 923         mutex_lock(&rfkill_global_mutex);
 924         rfkill_event(rfkill);
 925         mutex_unlock(&rfkill_global_mutex);
 926 }
 927
 928 static void rfkill_sync_work(struct work_struct *work)
 929 {
 930         struct rfkill *rfkill;
 931         bool cur;
 932
 933         rfkill = container_of(work, struct rfkill, sync_work);
 934
 935         mutex_lock(&rfkill_global_mutex);
 936         cur = rfkill_global_states[rfkill->type].cur;
 937         rfkill_set_block(rfkill, cur);
 938         mutex_unlock(&rfkill_global_mutex);
 939 }
 940
 941 int __must_check rfkill_register(struct rfkill *rfkill)
 942 {
 943         static unsigned long rfkill_no;
 944         struct device *dev = &rfkill->dev;
 945         int error;
 946
 947         BUG_ON(!rfkill);
 948
 949         mutex_lock(&rfkill_global_mutex);
 950
 951         if (rfkill->registered) {
 952                 error = -EALREADY;
 953                 goto unlock;
 954         }
 955
 956         rfkill->idx = rfkill_no;
 957         dev_set_name(dev, "rfkill%lu", rfkill_no);
 958         rfkill_no++;
 959
 960         list_add_tail(&rfkill->node, &rfkill_list);
 961
 962         error = device_add(dev);
 963         if (error)
 964                 goto remove;
 965
 966         error = rfkill_led_trigger_register(rfkill);
 967         if (error)
 968                 goto devdel;
 969
 970         rfkill->registered = true;
 971
 972         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 973         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 974         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 975
 976         if (rfkill->ops->poll)
 977                 queue_delayed_work(system_power_efficient_wq,
 978                         &rfkill->poll_work,
 979                         round_jiffies_relative(POLL_INTERVAL));
 980
 981         if (!rfkill->persistent || rfkill_epo_lock_active) {
 982                 schedule_work(&rfkill->sync_work);
 983         } else {
 984 #ifdef CONFIG_RFKILL_INPUT
 985                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 986
 987                 if (!atomic_read(&rfkill_input_disabled))
 988                         __rfkill_switch_all(rfkill->type, soft_blocked);
 989 #endif
 990         }
 991
 992         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 993
 994         mutex_unlock(&rfkill_global_mutex);
 995         return 0;
 996
 997  devdel:
 998         device_del(&rfkill->dev);
 999  remove:
1000         list_del_init(&rfkill->node);
1001  unlock:
1002         mutex_unlock(&rfkill_global_mutex);
1003         return error;
1004 }
1005 EXPORT_SYMBOL(rfkill_register);
1006
1007 void rfkill_unregister(struct rfkill *rfkill)
1008 {
1009         BUG_ON(!rfkill);
1010
1011         if (rfkill->ops->poll)
1012                 cancel_delayed_work_sync(&rfkill->poll_work);
1013
1014         cancel_work_sync(&rfkill->uevent_work);
1015         cancel_work_sync(&rfkill->sync_work);
1016
1017         rfkill->registered = false;
1018
1019         device_del(&rfkill->dev);
1020
1021         mutex_lock(&rfkill_global_mutex);
1022         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1023         list_del_init(&rfkill->node);
1024         mutex_unlock(&rfkill_global_mutex);
1025
1026         rfkill_led_trigger_unregister(rfkill);
1027 }
1028 EXPORT_SYMBOL(rfkill_unregister);
1029
1030 void rfkill_destroy(struct rfkill *rfkill)
1031 {
1032         if (rfkill)
1033                 put_device(&rfkill->dev);
1034 }
1035 EXPORT_SYMBOL(rfkill_destroy);
1036
1037 static int rfkill_fop_open(struct inode *inode, struct file *file)
1038 {
1039         struct rfkill_data *data;
1040         struct rfkill *rfkill;
1041         struct rfkill_int_event *ev, *tmp;
1042
1043         data = kzalloc(sizeof(*data), GFP_KERNEL);
1044         if (!data)
1045                 return -ENOMEM;
1046
1047         INIT_LIST_HEAD(&data->events);
1048         mutex_init(&data->mtx);
1049         init_waitqueue_head(&data->read_wait);
1050
1051         mutex_lock(&rfkill_global_mutex);
1052         mutex_lock(&data->mtx);
1053         /*
1054          * start getting events from elsewhere but hold mtx to get
1055          * startup events added first
1056          */
1057
1058         list_for_each_entry(rfkill, &rfkill_list, node) {
1059                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1060                 if (!ev)
1061                         goto free;
1062                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1063                 list_add_tail(&ev->list, &data->events);
1064         }
1065         list_add(&data->list, &rfkill_fds);
1066         mutex_unlock(&data->mtx);
1067         mutex_unlock(&rfkill_global_mutex);
1068
1069         file->private_data = data;
1070
1071         return nonseekable_open(inode, file);
1072
1073  free:
1074         mutex_unlock(&data->mtx);
1075         mutex_unlock(&rfkill_global_mutex);
1076         mutex_destroy(&data->mtx);
1077         list_for_each_entry_safe(ev, tmp, &data->events, list)
1078                 kfree(ev);
1079         kfree(data);
1080         return -ENOMEM;
1081 }
1082
1083 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1084 {
1085         struct rfkill_data *data = file->private_data;
1086         unsigned int res = POLLOUT | POLLWRNORM;
1087
1088         poll_wait(file, &data->read_wait, wait);
1089
1090         mutex_lock(&data->mtx);
1091         if (!list_empty(&data->events))
1092                 res = POLLIN | POLLRDNORM;
1093         mutex_unlock(&data->mtx);
1094
1095         return res;
1096 }
1097
1098 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1099                                size_t count, loff_t *pos)
1100 {
1101         struct rfkill_data *data = file->private_data;
1102         struct rfkill_int_event *ev;
1103         unsigned long sz;
1104         int ret;
1105
1106         mutex_lock(&data->mtx);
1107
1108         while (list_empty(&data->events)) {
1109                 if (file->f_flags & O_NONBLOCK) {
1110                         ret = -EAGAIN;
1111                         goto out;
1112                 }
1113                 mutex_unlock(&data->mtx);
1114                 /* since we re-check and it just compares pointers,
1115                  * using !list_empty() without locking isn't a problem
1116                  */
1117                 ret = wait_event_interruptible(data->read_wait,
1118                                                !list_empty(&data->events));
1119                 mutex_lock(&data->mtx);
1120
1121                 if (ret)
1122                         goto out;
1123         }
1124
1125         ev = list_first_entry(&data->events, struct rfkill_int_event,
1126                                 list);
1127
1128         sz = min_t(unsigned long, sizeof(ev->ev), count);
1129         ret = sz;
1130         if (copy_to_user(buf, &ev->ev, sz))
1131                 ret = -EFAULT;
1132
1133         list_del(&ev->list);
1134         kfree(ev);
1135  out:
1136         mutex_unlock(&data->mtx);
1137         return ret;
1138 }
1139
1140 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1141                                 size_t count, loff_t *pos)
1142 {
1143         struct rfkill *rfkill;
1144         struct rfkill_event ev;
1145
1146         /* we don't need the 'hard' variable but accept it */
1147         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1148                 return -EINVAL;
1149
1150         /*
1151          * Copy as much data as we can accept into our 'ev' buffer,
1152          * but tell userspace how much we've copied so it can determine
1153          * our API version even in a write() call, if it cares.
1154          */
1155         count = min(count, sizeof(ev));
1156         if (copy_from_user(&ev, buf, count))
1157                 return -EFAULT;
1158
1159         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1160                 return -EINVAL;
1161
1162         if (ev.type >= NUM_RFKILL_TYPES)
1163                 return -EINVAL;
1164
1165         mutex_lock(&rfkill_global_mutex);
1166
1167         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1168                 if (ev.type == RFKILL_TYPE_ALL) {
1169                         enum rfkill_type i;
1170                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1171                                 rfkill_global_states[i].cur = ev.soft;
1172                 } else {
1173                         rfkill_global_states[ev.type].cur = ev.soft;
1174                 }
1175         }
1176
1177         list_for_each_entry(rfkill, &rfkill_list, node) {
1178                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1179                         continue;
1180
1181                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1182                         continue;
1183
1184                 rfkill_set_block(rfkill, ev.soft);
1185         }
1186         mutex_unlock(&rfkill_global_mutex);
1187
1188         return count;
1189 }
1190
1191 static int rfkill_fop_release(struct inode *inode, struct file *file)
1192 {
1193         struct rfkill_data *data = file->private_data;
1194         struct rfkill_int_event *ev, *tmp;
1195
1196         mutex_lock(&rfkill_global_mutex);
1197         list_del(&data->list);
1198         mutex_unlock(&rfkill_global_mutex);
1199
1200         mutex_destroy(&data->mtx);
1201         list_for_each_entry_safe(ev, tmp, &data->events, list)
1202                 kfree(ev);
1203
1204 #ifdef CONFIG_RFKILL_INPUT
1205         if (data->input_handler)
1206                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1207                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1208 #endif
1209
1210         kfree(data);
1211
1212         return 0;
1213 }
1214
1215 #ifdef CONFIG_RFKILL_INPUT
1216 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1217                              unsigned long arg)
1218 {
1219         struct rfkill_data *data = file->private_data;
1220
1221         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1222                 return -ENOSYS;
1223
1224         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1225                 return -ENOSYS;
1226
1227         mutex_lock(&data->mtx);
1228
1229         if (!data->input_handler) {
1230                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1231                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1232                 data->input_handler = true;
1233         }
1234
1235         mutex_unlock(&data->mtx);
1236
1237         return 0;
1238 }
1239 #endif
1240
1241 static const struct file_operations rfkill_fops = {
1242         .owner          = THIS_MODULE,
1243         .open           = rfkill_fop_open,
1244         .read           = rfkill_fop_read,
1245         .write          = rfkill_fop_write,
1246         .poll           = rfkill_fop_poll,
1247         .release        = rfkill_fop_release,
1248 #ifdef CONFIG_RFKILL_INPUT
1249         .unlocked_ioctl = rfkill_fop_ioctl,
1250         .compat_ioctl   = rfkill_fop_ioctl,
1251 #endif
1252         .llseek         = no_llseek,
1253 };
1254
1255 static struct miscdevice rfkill_miscdev = {
1256         .name   = "rfkill",
1257         .fops   = &rfkill_fops,
1258         .minor  = MISC_DYNAMIC_MINOR,
1259 };
1260
1261 static int __init rfkill_init(void)
1262 {
1263         int error;
1264         int i;
1265
1266         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1267                 rfkill_global_states[i].cur = !rfkill_default_state;
1268
1269         error = class_register(&rfkill_class);
1270         if (error)
1271                 goto out;
1272
1273         error = misc_register(&rfkill_miscdev);
1274         if (error) {
1275                 class_unregister(&rfkill_class);
1276                 goto out;
1277         }
1278
1279 #ifdef CONFIG_RFKILL_INPUT
1280         error = rfkill_handler_init();
1281         if (error) {
1282                 misc_deregister(&rfkill_miscdev);
1283                 class_unregister(&rfkill_class);
1284                 goto out;
1285         }
1286 #endif
1287
1288  out:
1289         return error;
1290 }
1291 subsys_initcall(rfkill_init);
1292
1293 static void __exit rfkill_exit(void)
1294 {
1295 #ifdef CONFIG_RFKILL_INPUT
1296         rfkill_handler_exit();
1297 #endif
1298         misc_deregister(&rfkill_miscdev);
1299         class_unregister(&rfkill_class);
1300 }
1301 module_exit(rfkill_exit);