kernel/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         const char              *name;
  53         enum rfkill_type        type;
  54
  55         unsigned long           state;
  56
  57         u32                     idx;
  58
  59         bool                    registered;
  60         bool                    persistent;
  61
  62         const struct rfkill_ops *ops;
  63         void                    *data;
  64
  65 #ifdef CONFIG_RFKILL_LEDS
  66         struct led_trigger      led_trigger;
  67         const char              *ledtrigname;
  68 #endif
  69
  70         struct device           dev;
  71         struct list_head        node;
  72
  73         struct delayed_work     poll_work;
  74         struct work_struct      uevent_work;
  75         struct work_struct      sync_work;
  76 };
  77 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
  78
  79 struct rfkill_int_event {
  80         struct list_head        list;
  81         struct rfkill_event     ev;
  82 };
  83
  84 struct rfkill_data {
  85         struct list_head        list;
  86         struct list_head        events;
  87         struct mutex            mtx;
  88         wait_queue_head_t       read_wait;
  89         bool                    input_handler;
  90 };
  91
  92
  93 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  94 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  95 MODULE_DESCRIPTION("RF switch support");
  96 MODULE_LICENSE("GPL");
  97
  98
  99 /*
 100  * The locking here should be made much smarter, we currently have
 101  * a bit of a stupid situation because drivers might want to register
 102  * the rfkill struct under their own lock, and take this lock during
 103  * rfkill method calls -- which will cause an AB-BA deadlock situation.
 104  *
 105  * To fix that, we need to rework this code here to be mostly lock-free
 106  * and only use the mutex for list manipulations, not to protect the
 107  * various other global variables. Then we can avoid holding the mutex
 108  * around driver operations, and all is happy.
 109  */
 110 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 111 static DEFINE_MUTEX(rfkill_global_mutex);
 112 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 113
 114 static unsigned int rfkill_default_state = 1;
 115 module_param_named(default_state, rfkill_default_state, uint, 0444);
 116 MODULE_PARM_DESC(default_state,
 117                  "Default initial state for all radio types, 0 = radio off");
 118
 119 static struct {
 120         bool cur, sav;
 121 } rfkill_global_states[NUM_RFKILL_TYPES];
 122
 123 static bool rfkill_epo_lock_active;
 124
 125
 126 #ifdef CONFIG_RFKILL_LEDS
 127 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 128 {
 129         struct led_trigger *trigger;
 130
 131         if (!rfkill->registered)
 132                 return;
 133
 134         trigger = &rfkill->led_trigger;
 135
 136         if (rfkill->state & RFKILL_BLOCK_ANY)
 137                 led_trigger_event(trigger, LED_OFF);
 138         else
 139                 led_trigger_event(trigger, LED_FULL);
 140 }
 141
 142 static void rfkill_led_trigger_activate(struct led_classdev *led)
 143 {
 144         struct rfkill *rfkill;
 145
 146         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 147
 148         rfkill_led_trigger_event(rfkill);
 149 }
 150
 151 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 152 {
 153         return rfkill->led_trigger.name;
 154 }
 155 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 156
 157 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 158 {
 159         BUG_ON(!rfkill);
 160
 161         rfkill->ledtrigname = name;
 162 }
 163 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 164
 165 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 166 {
 167         rfkill->led_trigger.name = rfkill->ledtrigname
 168                                         ? : dev_name(&rfkill->dev);
 169         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 170         return led_trigger_register(&rfkill->led_trigger);
 171 }
 172
 173 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 174 {
 175         led_trigger_unregister(&rfkill->led_trigger);
 176 }
 177 #else
 178 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 179 {
 180 }
 181
 182 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 183 {
 184         return 0;
 185 }
 186
 187 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 188 {
 189 }
 190 #endif /* CONFIG_RFKILL_LEDS */
 191
 192 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 193                               enum rfkill_operation op)
 194 {
 195         unsigned long flags;
 196
 197         ev->idx = rfkill->idx;
 198         ev->type = rfkill->type;
 199         ev->op = op;
 200
 201         spin_lock_irqsave(&rfkill->lock, flags);
 202         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 203         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 204                                         RFKILL_BLOCK_SW_PREV));
 205         spin_unlock_irqrestore(&rfkill->lock, flags);
 206 }
 207
 208 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 209 {
 210         struct rfkill_data *data;
 211         struct rfkill_int_event *ev;
 212
 213         list_for_each_entry(data, &rfkill_fds, list) {
 214                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 215                 if (!ev)
 216                         continue;
 217                 rfkill_fill_event(&ev->ev, rfkill, op);
 218                 mutex_lock(&data->mtx);
 219                 list_add_tail(&ev->list, &data->events);
 220                 mutex_unlock(&data->mtx);
 221                 wake_up_interruptible(&data->read_wait);
 222         }
 223 }
 224
 225 static void rfkill_event(struct rfkill *rfkill)
 226 {
 227         if (!rfkill->registered)
 228                 return;
 229
 230         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 231
 232         /* also send event to /dev/rfkill */
 233         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 234 }
 235
 236 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
 237                                   bool blocked, bool *change)
 238 {
 239         unsigned long flags;
 240         bool prev, any;
 241
 242         BUG_ON(!rfkill);
 243
 244         spin_lock_irqsave(&rfkill->lock, flags);
 245         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 246         if (blocked)
 247                 rfkill->state |= RFKILL_BLOCK_HW;
 248         else
 249                 rfkill->state &= ~RFKILL_BLOCK_HW;
 250         *change = prev != blocked;
 251         any = !!(rfkill->state & RFKILL_BLOCK_ANY);
 252         spin_unlock_irqrestore(&rfkill->lock, flags);
 253
 254         rfkill_led_trigger_event(rfkill);
 255
 256         return any;
 257 }
 258
 259 /**
 260  * rfkill_set_block - wrapper for set_block method
 261  *
 262  * @rfkill: the rfkill struct to use
 263  * @blocked: the new software state
 264  *
 265  * Calls the set_block method (when applicable) and handles notifications
 266  * etc. as well.
 267  */
 268 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 269 {
 270         unsigned long flags;
 271         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         rfkill_global_states[type].cur = blocked;
 345         list_for_each_entry(rfkill, &rfkill_list, node) {
 346                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 347                         continue;
 348
 349                 rfkill_set_block(rfkill, blocked);
 350         }
 351 }
 352
 353 /**
 354  * rfkill_switch_all - Toggle state of all switches of given type
 355  * @type: type of interfaces to be affected
 356  * @blocked: the new state
 357  *
 358  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 359  * Please refer to __rfkill_switch_all() for details.
 360  *
 361  * Does nothing if the EPO lock is active.
 362  */
 363 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 364 {
 365         if (atomic_read(&rfkill_input_disabled))
 366                 return;
 367
 368         mutex_lock(&rfkill_global_mutex);
 369
 370         if (!rfkill_epo_lock_active)
 371                 __rfkill_switch_all(type, blocked);
 372
 373         mutex_unlock(&rfkill_global_mutex);
 374 }
 375
 376 /**
 377  * rfkill_epo - emergency power off all transmitters
 378  *
 379  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 380  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 381  *
 382  * The global state before the EPO is saved and can be restored later
 383  * using rfkill_restore_states().
 384  */
 385 void rfkill_epo(void)
 386 {
 387         struct rfkill *rfkill;
 388         int i;
 389
 390         if (atomic_read(&rfkill_input_disabled))
 391                 return;
 392
 393         mutex_lock(&rfkill_global_mutex);
 394
 395         rfkill_epo_lock_active = true;
 396         list_for_each_entry(rfkill, &rfkill_list, node)
 397                 rfkill_set_block(rfkill, true);
 398
 399         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 400                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 401                 rfkill_global_states[i].cur = true;
 402         }
 403
 404         mutex_unlock(&rfkill_global_mutex);
 405 }
 406
 407 /**
 408  * rfkill_restore_states - restore global states
 409  *
 410  * Restore (and sync switches to) the global state from the
 411  * states in rfkill_default_states.  This can undo the effects of
 412  * a call to rfkill_epo().
 413  */
 414 void rfkill_restore_states(void)
 415 {
 416         int i;
 417
 418         if (atomic_read(&rfkill_input_disabled))
 419                 return;
 420
 421         mutex_lock(&rfkill_global_mutex);
 422
 423         rfkill_epo_lock_active = false;
 424         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 425                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 426         mutex_unlock(&rfkill_global_mutex);
 427 }
 428
 429 /**
 430  * rfkill_remove_epo_lock - unlock state changes
 431  *
 432  * Used by rfkill-input manually unlock state changes, when
 433  * the EPO switch is deactivated.
 434  */
 435 void rfkill_remove_epo_lock(void)
 436 {
 437         if (atomic_read(&rfkill_input_disabled))
 438                 return;
 439
 440         mutex_lock(&rfkill_global_mutex);
 441         rfkill_epo_lock_active = false;
 442         mutex_unlock(&rfkill_global_mutex);
 443 }
 444
 445 /**
 446  * rfkill_is_epo_lock_active - returns true EPO is active
 447  *
 448  * Returns 0 (false) if there is NOT an active EPO contidion,
 449  * and 1 (true) if there is an active EPO contition, which
 450  * locks all radios in one of the BLOCKED states.
 451  *
 452  * Can be called in atomic context.
 453  */
 454 bool rfkill_is_epo_lock_active(void)
 455 {
 456         return rfkill_epo_lock_active;
 457 }
 458
 459 /**
 460  * rfkill_get_global_sw_state - returns global state for a type
 461  * @type: the type to get the global state of
 462  *
 463  * Returns the current global state for a given wireless
 464  * device type.
 465  */
 466 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 467 {
 468         return rfkill_global_states[type].cur;
 469 }
 470 #endif
 471
 472
 473 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 474 {
 475         bool ret, change;
 476
 477         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 478
 479         if (!rfkill->registered)
 480                 return ret;
 481
 482         if (change)
 483                 schedule_work(&rfkill->uevent_work);
 484
 485         return ret;
 486 }
 487 EXPORT_SYMBOL(rfkill_set_hw_state);
 488
 489 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 490 {
 491         u32 bit = RFKILL_BLOCK_SW;
 492
 493         /* if in a ops->set_block right now, use other bit */
 494         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 495                 bit = RFKILL_BLOCK_SW_PREV;
 496
 497         if (blocked)
 498                 rfkill->state |= bit;
 499         else
 500                 rfkill->state &= ~bit;
 501 }
 502
 503 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 504 {
 505         unsigned long flags;
 506         bool prev, hwblock;
 507
 508         BUG_ON(!rfkill);
 509
 510         spin_lock_irqsave(&rfkill->lock, flags);
 511         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 512         __rfkill_set_sw_state(rfkill, blocked);
 513         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 514         blocked = blocked || hwblock;
 515         spin_unlock_irqrestore(&rfkill->lock, flags);
 516
 517         if (!rfkill->registered)
 518                 return blocked;
 519
 520         if (prev != blocked && !hwblock)
 521                 schedule_work(&rfkill->uevent_work);
 522
 523         rfkill_led_trigger_event(rfkill);
 524
 525         return blocked;
 526 }
 527 EXPORT_SYMBOL(rfkill_set_sw_state);
 528
 529 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 530 {
 531         unsigned long flags;
 532
 533         BUG_ON(!rfkill);
 534         BUG_ON(rfkill->registered);
 535
 536         spin_lock_irqsave(&rfkill->lock, flags);
 537         __rfkill_set_sw_state(rfkill, blocked);
 538         rfkill->persistent = true;
 539         spin_unlock_irqrestore(&rfkill->lock, flags);
 540 }
 541 EXPORT_SYMBOL(rfkill_init_sw_state);
 542
 543 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 544 {
 545         unsigned long flags;
 546         bool swprev, hwprev;
 547
 548         BUG_ON(!rfkill);
 549
 550         spin_lock_irqsave(&rfkill->lock, flags);
 551
 552         /*
 553          * No need to care about prev/setblock ... this is for uevent only
 554          * and that will get triggered by rfkill_set_block anyway.
 555          */
 556         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 557         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 558         __rfkill_set_sw_state(rfkill, sw);
 559         if (hw)
 560                 rfkill->state |= RFKILL_BLOCK_HW;
 561         else
 562                 rfkill->state &= ~RFKILL_BLOCK_HW;
 563
 564         spin_unlock_irqrestore(&rfkill->lock, flags);
 565
 566         if (!rfkill->registered) {
 567                 rfkill->persistent = true;
 568         } else {
 569                 if (swprev != sw || hwprev != hw)
 570                         schedule_work(&rfkill->uevent_work);
 571
 572                 rfkill_led_trigger_event(rfkill);
 573         }
 574 }
 575 EXPORT_SYMBOL(rfkill_set_states);
 576
 577 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 578                          char *buf)
 579 {
 580         struct rfkill *rfkill = to_rfkill(dev);
 581
 582         return sprintf(buf, "%s\n", rfkill->name);
 583 }
 584 static DEVICE_ATTR_RO(name);
 585
 586 static const char *rfkill_get_type_str(enum rfkill_type type)
 587 {
 588         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_NFC + 1);
 589
 590         switch (type) {
 591         case RFKILL_TYPE_WLAN:
 592                 return "wlan";
 593         case RFKILL_TYPE_BLUETOOTH:
 594                 return "bluetooth";
 595         case RFKILL_TYPE_UWB:
 596                 return "ultrawideband";
 597         case RFKILL_TYPE_WIMAX:
 598                 return "wimax";
 599         case RFKILL_TYPE_WWAN:
 600                 return "wwan";
 601         case RFKILL_TYPE_GPS:
 602                 return "gps";
 603         case RFKILL_TYPE_FM:
 604                 return "fm";
 605         case RFKILL_TYPE_NFC:
 606                 return "nfc";
 607         default:
 608                 BUG();
 609         }
 610 }
 611
 612 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 613                          char *buf)
 614 {
 615         struct rfkill *rfkill = to_rfkill(dev);
 616
 617         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 618 }
 619 static DEVICE_ATTR_RO(type);
 620
 621 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 622                           char *buf)
 623 {
 624         struct rfkill *rfkill = to_rfkill(dev);
 625
 626         return sprintf(buf, "%d\n", rfkill->idx);
 627 }
 628 static DEVICE_ATTR_RO(index);
 629
 630 static ssize_t persistent_show(struct device *dev,
 631                                struct device_attribute *attr, char *buf)
 632 {
 633         struct rfkill *rfkill = to_rfkill(dev);
 634
 635         return sprintf(buf, "%d\n", rfkill->persistent);
 636 }
 637 static DEVICE_ATTR_RO(persistent);
 638
 639 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 640                          char *buf)
 641 {
 642         struct rfkill *rfkill = to_rfkill(dev);
 643
 644         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 645 }
 646 static DEVICE_ATTR_RO(hard);
 647
 648 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 649                          char *buf)
 650 {
 651         struct rfkill *rfkill = to_rfkill(dev);
 652
 653         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 654 }
 655
 656 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 657                           const char *buf, size_t count)
 658 {
 659         struct rfkill *rfkill = to_rfkill(dev);
 660         unsigned long state;
 661         int err;
 662
 663         if (!capable(CAP_NET_ADMIN))
 664                 return -EPERM;
 665
 666         err = kstrtoul(buf, 0, &state);
 667         if (err)
 668                 return err;
 669
 670         if (state > 1 )
 671                 return -EINVAL;
 672
 673         mutex_lock(&rfkill_global_mutex);
 674         rfkill_set_block(rfkill, state);
 675         mutex_unlock(&rfkill_global_mutex);
 676
 677         return count;
 678 }
 679 static DEVICE_ATTR_RW(soft);
 680
 681 static u8 user_state_from_blocked(unsigned long state)
 682 {
 683         if (state & RFKILL_BLOCK_HW)
 684                 return RFKILL_USER_STATE_HARD_BLOCKED;
 685         if (state & RFKILL_BLOCK_SW)
 686                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 687
 688         return RFKILL_USER_STATE_UNBLOCKED;
 689 }
 690
 691 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 692                           char *buf)
 693 {
 694         struct rfkill *rfkill = to_rfkill(dev);
 695
 696         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 697 }
 698
 699 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 700                            const char *buf, size_t count)
 701 {
 702         struct rfkill *rfkill = to_rfkill(dev);
 703         unsigned long state;
 704         int err;
 705
 706         if (!capable(CAP_NET_ADMIN))
 707                 return -EPERM;
 708
 709         err = kstrtoul(buf, 0, &state);
 710         if (err)
 711                 return err;
 712
 713         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 714             state != RFKILL_USER_STATE_UNBLOCKED)
 715                 return -EINVAL;
 716
 717         mutex_lock(&rfkill_global_mutex);
 718         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 719         mutex_unlock(&rfkill_global_mutex);
 720
 721         return count;
 722 }
 723 static DEVICE_ATTR_RW(state);
 724
 725 static ssize_t claim_show(struct device *dev, struct device_attribute *attr,
 726                           char *buf)
 727 {
 728         return sprintf(buf, "%d\n", 0);
 729 }
 730 static DEVICE_ATTR_RO(claim);
 731
 732 static struct attribute *rfkill_dev_attrs[] = {
 733         &dev_attr_name.attr,
 734         &dev_attr_type.attr,
 735         &dev_attr_index.attr,
 736         &dev_attr_persistent.attr,
 737         &dev_attr_state.attr,
 738         &dev_attr_claim.attr,
 739         &dev_attr_soft.attr,
 740         &dev_attr_hard.attr,
 741         NULL,
 742 };
 743 ATTRIBUTE_GROUPS(rfkill_dev);
 744
 745 static void rfkill_release(struct device *dev)
 746 {
 747         struct rfkill *rfkill = to_rfkill(dev);
 748
 749         kfree(rfkill);
 750 }
 751
 752 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 753 {
 754         struct rfkill *rfkill = to_rfkill(dev);
 755         unsigned long flags;
 756         u32 state;
 757         int error;
 758
 759         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 760         if (error)
 761                 return error;
 762         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 763                                rfkill_get_type_str(rfkill->type));
 764         if (error)
 765                 return error;
 766         spin_lock_irqsave(&rfkill->lock, flags);
 767         state = rfkill->state;
 768         spin_unlock_irqrestore(&rfkill->lock, flags);
 769         error = add_uevent_var(env, "RFKILL_STATE=%d",
 770                                user_state_from_blocked(state));
 771         return error;
 772 }
 773
 774 void rfkill_pause_polling(struct rfkill *rfkill)
 775 {
 776         BUG_ON(!rfkill);
 777
 778         if (!rfkill->ops->poll)
 779                 return;
 780
 781         cancel_delayed_work_sync(&rfkill->poll_work);
 782 }
 783 EXPORT_SYMBOL(rfkill_pause_polling);
 784
 785 void rfkill_resume_polling(struct rfkill *rfkill)
 786 {
 787         BUG_ON(!rfkill);
 788
 789         if (!rfkill->ops->poll)
 790                 return;
 791
 792         queue_delayed_work(system_power_efficient_wq,
 793                            &rfkill->poll_work, 0);
 794 }
 795 EXPORT_SYMBOL(rfkill_resume_polling);
 796
 797 static int rfkill_suspend(struct device *dev, pm_message_t state)
 798 {
 799         struct rfkill *rfkill = to_rfkill(dev);
 800
 801         rfkill_pause_polling(rfkill);
 802
 803         return 0;
 804 }
 805
 806 static int rfkill_resume(struct device *dev)
 807 {
 808         struct rfkill *rfkill = to_rfkill(dev);
 809         bool cur;
 810
 811         if (!rfkill->persistent) {
 812                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 813                 rfkill_set_block(rfkill, cur);
 814         }
 815
 816         rfkill_resume_polling(rfkill);
 817
 818         return 0;
 819 }
 820
 821 static struct class rfkill_class = {
 822         .name           = "rfkill",
 823         .dev_release    = rfkill_release,
 824         .dev_groups     = rfkill_dev_groups,
 825         .dev_uevent     = rfkill_dev_uevent,
 826         .suspend        = rfkill_suspend,
 827         .resume         = rfkill_resume,
 828 };
 829
 830 bool rfkill_blocked(struct rfkill *rfkill)
 831 {
 832         unsigned long flags;
 833         u32 state;
 834
 835         spin_lock_irqsave(&rfkill->lock, flags);
 836         state = rfkill->state;
 837         spin_unlock_irqrestore(&rfkill->lock, flags);
 838
 839         return !!(state & RFKILL_BLOCK_ANY);
 840 }
 841 EXPORT_SYMBOL(rfkill_blocked);
 842
 843
 844 struct rfkill * __must_check rfkill_alloc(const char *name,
 845                                           struct device *parent,
 846                                           const enum rfkill_type type,
 847                                           const struct rfkill_ops *ops,
 848                                           void *ops_data)
 849 {
 850         struct rfkill *rfkill;
 851         struct device *dev;
 852
 853         if (WARN_ON(!ops))
 854                 return NULL;
 855
 856         if (WARN_ON(!ops->set_block))
 857                 return NULL;
 858
 859         if (WARN_ON(!name))
 860                 return NULL;
 861
 862         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 863                 return NULL;
 864
 865         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 866         if (!rfkill)
 867                 return NULL;
 868
 869         spin_lock_init(&rfkill->lock);
 870         INIT_LIST_HEAD(&rfkill->node);
 871         rfkill->type = type;
 872         rfkill->name = name;
 873         rfkill->ops = ops;
 874         rfkill->data = ops_data;
 875
 876         dev = &rfkill->dev;
 877         dev->class = &rfkill_class;
 878         dev->parent = parent;
 879         device_initialize(dev);
 880
 881         return rfkill;
 882 }
 883 EXPORT_SYMBOL(rfkill_alloc);
 884
 885 static void rfkill_poll(struct work_struct *work)
 886 {
 887         struct rfkill *rfkill;
 888
 889         rfkill = container_of(work, struct rfkill, poll_work.work);
 890
 891         /*
 892          * Poll hardware state -- driver will use one of the
 893          * rfkill_set{,_hw,_sw}_state functions and use its
 894          * return value to update the current status.
 895          */
 896         rfkill->ops->poll(rfkill, rfkill->data);
 897
 898         queue_delayed_work(system_power_efficient_wq,
 899                 &rfkill->poll_work,
 900                 round_jiffies_relative(POLL_INTERVAL));
 901 }
 902
 903 static void rfkill_uevent_work(struct work_struct *work)
 904 {
 905         struct rfkill *rfkill;
 906
 907         rfkill = container_of(work, struct rfkill, uevent_work);
 908
 909         mutex_lock(&rfkill_global_mutex);
 910         rfkill_event(rfkill);
 911         mutex_unlock(&rfkill_global_mutex);
 912 }
 913
 914 static void rfkill_sync_work(struct work_struct *work)
 915 {
 916         struct rfkill *rfkill;
 917         bool cur;
 918
 919         rfkill = container_of(work, struct rfkill, sync_work);
 920
 921         mutex_lock(&rfkill_global_mutex);
 922         cur = rfkill_global_states[rfkill->type].cur;
 923         rfkill_set_block(rfkill, cur);
 924         mutex_unlock(&rfkill_global_mutex);
 925 }
 926
 927 int __must_check rfkill_register(struct rfkill *rfkill)
 928 {
 929         static unsigned long rfkill_no;
 930         struct device *dev = &rfkill->dev;
 931         int error;
 932
 933         BUG_ON(!rfkill);
 934
 935         mutex_lock(&rfkill_global_mutex);
 936
 937         if (rfkill->registered) {
 938                 error = -EALREADY;
 939                 goto unlock;
 940         }
 941
 942         rfkill->idx = rfkill_no;
 943         dev_set_name(dev, "rfkill%lu", rfkill_no);
 944         rfkill_no++;
 945
 946         list_add_tail(&rfkill->node, &rfkill_list);
 947
 948         error = device_add(dev);
 949         if (error)
 950                 goto remove;
 951
 952         error = rfkill_led_trigger_register(rfkill);
 953         if (error)
 954                 goto devdel;
 955
 956         rfkill->registered = true;
 957
 958         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 959         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 960         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 961
 962         if (rfkill->ops->poll)
 963                 queue_delayed_work(system_power_efficient_wq,
 964                         &rfkill->poll_work,
 965                         round_jiffies_relative(POLL_INTERVAL));
 966
 967         if (!rfkill->persistent || rfkill_epo_lock_active) {
 968                 schedule_work(&rfkill->sync_work);
 969         } else {
 970 #ifdef CONFIG_RFKILL_INPUT
 971                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 972
 973                 if (!atomic_read(&rfkill_input_disabled))
 974                         __rfkill_switch_all(rfkill->type, soft_blocked);
 975 #endif
 976         }
 977
 978         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 979
 980         mutex_unlock(&rfkill_global_mutex);
 981         return 0;
 982
 983  devdel:
 984         device_del(&rfkill->dev);
 985  remove:
 986         list_del_init(&rfkill->node);
 987  unlock:
 988         mutex_unlock(&rfkill_global_mutex);
 989         return error;
 990 }
 991 EXPORT_SYMBOL(rfkill_register);
 992
 993 void rfkill_unregister(struct rfkill *rfkill)
 994 {
 995         BUG_ON(!rfkill);
 996
 997         if (rfkill->ops->poll)
 998                 cancel_delayed_work_sync(&rfkill->poll_work);
 999
1000         cancel_work_sync(&rfkill->uevent_work);
1001         cancel_work_sync(&rfkill->sync_work);
1002
1003         rfkill->registered = false;
1004
1005         device_del(&rfkill->dev);
1006
1007         mutex_lock(&rfkill_global_mutex);
1008         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1009         list_del_init(&rfkill->node);
1010         mutex_unlock(&rfkill_global_mutex);
1011
1012         rfkill_led_trigger_unregister(rfkill);
1013 }
1014 EXPORT_SYMBOL(rfkill_unregister);
1015
1016 void rfkill_destroy(struct rfkill *rfkill)
1017 {
1018         if (rfkill)
1019                 put_device(&rfkill->dev);
1020 }
1021 EXPORT_SYMBOL(rfkill_destroy);
1022
1023 static int rfkill_fop_open(struct inode *inode, struct file *file)
1024 {
1025         struct rfkill_data *data;
1026         struct rfkill *rfkill;
1027         struct rfkill_int_event *ev, *tmp;
1028
1029         data = kzalloc(sizeof(*data), GFP_KERNEL);
1030         if (!data)
1031                 return -ENOMEM;
1032
1033         INIT_LIST_HEAD(&data->events);
1034         mutex_init(&data->mtx);
1035         init_waitqueue_head(&data->read_wait);
1036
1037         mutex_lock(&rfkill_global_mutex);
1038         mutex_lock(&data->mtx);
1039         /*
1040          * start getting events from elsewhere but hold mtx to get
1041          * startup events added first
1042          */
1043
1044         list_for_each_entry(rfkill, &rfkill_list, node) {
1045                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1046                 if (!ev)
1047                         goto free;
1048                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1049                 list_add_tail(&ev->list, &data->events);
1050         }
1051         list_add(&data->list, &rfkill_fds);
1052         mutex_unlock(&data->mtx);
1053         mutex_unlock(&rfkill_global_mutex);
1054
1055         file->private_data = data;
1056
1057         return nonseekable_open(inode, file);
1058
1059  free:
1060         mutex_unlock(&data->mtx);
1061         mutex_unlock(&rfkill_global_mutex);
1062         mutex_destroy(&data->mtx);
1063         list_for_each_entry_safe(ev, tmp, &data->events, list)
1064                 kfree(ev);
1065         kfree(data);
1066         return -ENOMEM;
1067 }
1068
1069 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1070 {
1071         struct rfkill_data *data = file->private_data;
1072         unsigned int res = POLLOUT | POLLWRNORM;
1073
1074         poll_wait(file, &data->read_wait, wait);
1075
1076         mutex_lock(&data->mtx);
1077         if (!list_empty(&data->events))
1078                 res = POLLIN | POLLRDNORM;
1079         mutex_unlock(&data->mtx);
1080
1081         return res;
1082 }
1083
1084 static bool rfkill_readable(struct rfkill_data *data)
1085 {
1086         bool r;
1087
1088         mutex_lock(&data->mtx);
1089         r = !list_empty(&data->events);
1090         mutex_unlock(&data->mtx);
1091
1092         return r;
1093 }
1094
1095 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1096                                size_t count, loff_t *pos)
1097 {
1098         struct rfkill_data *data = file->private_data;
1099         struct rfkill_int_event *ev;
1100         unsigned long sz;
1101         int ret;
1102
1103         mutex_lock(&data->mtx);
1104
1105         while (list_empty(&data->events)) {
1106                 if (file->f_flags & O_NONBLOCK) {
1107                         ret = -EAGAIN;
1108                         goto out;
1109                 }
1110                 mutex_unlock(&data->mtx);
1111                 ret = wait_event_interruptible(data->read_wait,
1112                                                rfkill_readable(data));
1113                 mutex_lock(&data->mtx);
1114
1115                 if (ret)
1116                         goto out;
1117         }
1118
1119         ev = list_first_entry(&data->events, struct rfkill_int_event,
1120                                 list);
1121
1122         sz = min_t(unsigned long, sizeof(ev->ev), count);
1123         ret = sz;
1124         if (copy_to_user(buf, &ev->ev, sz))
1125                 ret = -EFAULT;
1126
1127         list_del(&ev->list);
1128         kfree(ev);
1129  out:
1130         mutex_unlock(&data->mtx);
1131         return ret;
1132 }
1133
1134 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1135                                 size_t count, loff_t *pos)
1136 {
1137         struct rfkill *rfkill;
1138         struct rfkill_event ev;
1139
1140         /* we don't need the 'hard' variable but accept it */
1141         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1142                 return -EINVAL;
1143
1144         /*
1145          * Copy as much data as we can accept into our 'ev' buffer,
1146          * but tell userspace how much we've copied so it can determine
1147          * our API version even in a write() call, if it cares.
1148          */
1149         count = min(count, sizeof(ev));
1150         if (copy_from_user(&ev, buf, count))
1151                 return -EFAULT;
1152
1153         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1154                 return -EINVAL;
1155
1156         if (ev.type >= NUM_RFKILL_TYPES)
1157                 return -EINVAL;
1158
1159         mutex_lock(&rfkill_global_mutex);
1160
1161         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1162                 if (ev.type == RFKILL_TYPE_ALL) {
1163                         enum rfkill_type i;
1164                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1165                                 rfkill_global_states[i].cur = ev.soft;
1166                 } else {
1167                         rfkill_global_states[ev.type].cur = ev.soft;
1168                 }
1169         }
1170
1171         list_for_each_entry(rfkill, &rfkill_list, node) {
1172                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1173                         continue;
1174
1175                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1176                         continue;
1177
1178                 rfkill_set_block(rfkill, ev.soft);
1179         }
1180         mutex_unlock(&rfkill_global_mutex);
1181
1182         return count;
1183 }
1184
1185 static int rfkill_fop_release(struct inode *inode, struct file *file)
1186 {
1187         struct rfkill_data *data = file->private_data;
1188         struct rfkill_int_event *ev, *tmp;
1189
1190         mutex_lock(&rfkill_global_mutex);
1191         list_del(&data->list);
1192         mutex_unlock(&rfkill_global_mutex);
1193
1194         mutex_destroy(&data->mtx);
1195         list_for_each_entry_safe(ev, tmp, &data->events, list)
1196                 kfree(ev);
1197
1198 #ifdef CONFIG_RFKILL_INPUT
1199         if (data->input_handler)
1200                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1201                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1202 #endif
1203
1204         kfree(data);
1205
1206         return 0;
1207 }
1208
1209 #ifdef CONFIG_RFKILL_INPUT
1210 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1211                              unsigned long arg)
1212 {
1213         struct rfkill_data *data = file->private_data;
1214
1215         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1216                 return -ENOSYS;
1217
1218         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1219                 return -ENOSYS;
1220
1221         mutex_lock(&data->mtx);
1222
1223         if (!data->input_handler) {
1224                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1225                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1226                 data->input_handler = true;
1227         }
1228
1229         mutex_unlock(&data->mtx);
1230
1231         return 0;
1232 }
1233 #endif
1234
1235 static const struct file_operations rfkill_fops = {
1236         .owner          = THIS_MODULE,
1237         .open           = rfkill_fop_open,
1238         .read           = rfkill_fop_read,
1239         .write          = rfkill_fop_write,
1240         .poll           = rfkill_fop_poll,
1241         .release        = rfkill_fop_release,
1242 #ifdef CONFIG_RFKILL_INPUT
1243         .unlocked_ioctl = rfkill_fop_ioctl,
1244         .compat_ioctl   = rfkill_fop_ioctl,
1245 #endif
1246         .llseek         = no_llseek,
1247 };
1248
1249 static struct miscdevice rfkill_miscdev = {
1250         .name   = "rfkill",
1251         .fops   = &rfkill_fops,
1252         .minor  = MISC_DYNAMIC_MINOR,
1253 };
1254
1255 static int __init rfkill_init(void)
1256 {
1257         int error;
1258         int i;
1259
1260         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1261                 rfkill_global_states[i].cur = !rfkill_default_state;
1262
1263         error = class_register(&rfkill_class);
1264         if (error)
1265                 goto out;
1266
1267         error = misc_register(&rfkill_miscdev);
1268         if (error) {
1269                 class_unregister(&rfkill_class);
1270                 goto out;
1271         }
1272
1273 #ifdef CONFIG_RFKILL_INPUT
1274         error = rfkill_handler_init();
1275         if (error) {
1276                 misc_deregister(&rfkill_miscdev);
1277                 class_unregister(&rfkill_class);
1278                 goto out;
1279         }
1280 #endif
1281
1282  out:
1283         return error;
1284 }
1285 subsys_initcall(rfkill_init);
1286
1287 static void __exit rfkill_exit(void)
1288 {
1289 #ifdef CONFIG_RFKILL_INPUT
1290         rfkill_handler_exit();
1291 #endif
1292         misc_deregister(&rfkill_miscdev);
1293         class_unregister(&rfkill_class);
1294 }
1295 module_exit(rfkill_exit);