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 #ifdef CONFIG_PM_SLEEP
 798 static int rfkill_suspend(struct device *dev)
 799 {
 800         struct rfkill *rfkill = to_rfkill(dev);
 801
 802         rfkill_pause_polling(rfkill);
 803
 804         return 0;
 805 }
 806
 807 static int rfkill_resume(struct device *dev)
 808 {
 809         struct rfkill *rfkill = to_rfkill(dev);
 810         bool cur;
 811
 812         if (!rfkill->persistent) {
 813                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 814                 rfkill_set_block(rfkill, cur);
 815         }
 816
 817         rfkill_resume_polling(rfkill);
 818
 819         return 0;
 820 }
 821
 822 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 823 #define RFKILL_PM_OPS (&rfkill_pm_ops)
 824 #else
 825 #define RFKILL_PM_OPS NULL
 826 #endif
 827
 828 static struct class rfkill_class = {
 829         .name           = "rfkill",
 830         .dev_release    = rfkill_release,
 831         .dev_groups     = rfkill_dev_groups,
 832         .dev_uevent     = rfkill_dev_uevent,
 833         .pm             = RFKILL_PM_OPS,
 834 };
 835
 836 bool rfkill_blocked(struct rfkill *rfkill)
 837 {
 838         unsigned long flags;
 839         u32 state;
 840
 841         spin_lock_irqsave(&rfkill->lock, flags);
 842         state = rfkill->state;
 843         spin_unlock_irqrestore(&rfkill->lock, flags);
 844
 845         return !!(state & RFKILL_BLOCK_ANY);
 846 }
 847 EXPORT_SYMBOL(rfkill_blocked);
 848
 849
 850 struct rfkill * __must_check rfkill_alloc(const char *name,
 851                                           struct device *parent,
 852                                           const enum rfkill_type type,
 853                                           const struct rfkill_ops *ops,
 854                                           void *ops_data)
 855 {
 856         struct rfkill *rfkill;
 857         struct device *dev;
 858
 859         if (WARN_ON(!ops))
 860                 return NULL;
 861
 862         if (WARN_ON(!ops->set_block))
 863                 return NULL;
 864
 865         if (WARN_ON(!name))
 866                 return NULL;
 867
 868         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 869                 return NULL;
 870
 871         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 872         if (!rfkill)
 873                 return NULL;
 874
 875         spin_lock_init(&rfkill->lock);
 876         INIT_LIST_HEAD(&rfkill->node);
 877         rfkill->type = type;
 878         rfkill->name = name;
 879         rfkill->ops = ops;
 880         rfkill->data = ops_data;
 881
 882         dev = &rfkill->dev;
 883         dev->class = &rfkill_class;
 884         dev->parent = parent;
 885         device_initialize(dev);
 886
 887         return rfkill;
 888 }
 889 EXPORT_SYMBOL(rfkill_alloc);
 890
 891 static void rfkill_poll(struct work_struct *work)
 892 {
 893         struct rfkill *rfkill;
 894
 895         rfkill = container_of(work, struct rfkill, poll_work.work);
 896
 897         /*
 898          * Poll hardware state -- driver will use one of the
 899          * rfkill_set{,_hw,_sw}_state functions and use its
 900          * return value to update the current status.
 901          */
 902         rfkill->ops->poll(rfkill, rfkill->data);
 903
 904         queue_delayed_work(system_power_efficient_wq,
 905                 &rfkill->poll_work,
 906                 round_jiffies_relative(POLL_INTERVAL));
 907 }
 908
 909 static void rfkill_uevent_work(struct work_struct *work)
 910 {
 911         struct rfkill *rfkill;
 912
 913         rfkill = container_of(work, struct rfkill, uevent_work);
 914
 915         mutex_lock(&rfkill_global_mutex);
 916         rfkill_event(rfkill);
 917         mutex_unlock(&rfkill_global_mutex);
 918 }
 919
 920 static void rfkill_sync_work(struct work_struct *work)
 921 {
 922         struct rfkill *rfkill;
 923         bool cur;
 924
 925         rfkill = container_of(work, struct rfkill, sync_work);
 926
 927         mutex_lock(&rfkill_global_mutex);
 928         cur = rfkill_global_states[rfkill->type].cur;
 929         rfkill_set_block(rfkill, cur);
 930         mutex_unlock(&rfkill_global_mutex);
 931 }
 932
 933 int __must_check rfkill_register(struct rfkill *rfkill)
 934 {
 935         static unsigned long rfkill_no;
 936         struct device *dev = &rfkill->dev;
 937         int error;
 938
 939         BUG_ON(!rfkill);
 940
 941         mutex_lock(&rfkill_global_mutex);
 942
 943         if (rfkill->registered) {
 944                 error = -EALREADY;
 945                 goto unlock;
 946         }
 947
 948         rfkill->idx = rfkill_no;
 949         dev_set_name(dev, "rfkill%lu", rfkill_no);
 950         rfkill_no++;
 951
 952         list_add_tail(&rfkill->node, &rfkill_list);
 953
 954         error = device_add(dev);
 955         if (error)
 956                 goto remove;
 957
 958         error = rfkill_led_trigger_register(rfkill);
 959         if (error)
 960                 goto devdel;
 961
 962         rfkill->registered = true;
 963
 964         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 965         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 966         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 967
 968         if (rfkill->ops->poll)
 969                 queue_delayed_work(system_power_efficient_wq,
 970                         &rfkill->poll_work,
 971                         round_jiffies_relative(POLL_INTERVAL));
 972
 973         if (!rfkill->persistent || rfkill_epo_lock_active) {
 974                 schedule_work(&rfkill->sync_work);
 975         } else {
 976 #ifdef CONFIG_RFKILL_INPUT
 977                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 978
 979                 if (!atomic_read(&rfkill_input_disabled))
 980                         __rfkill_switch_all(rfkill->type, soft_blocked);
 981 #endif
 982         }
 983
 984         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 985
 986         mutex_unlock(&rfkill_global_mutex);
 987         return 0;
 988
 989  devdel:
 990         device_del(&rfkill->dev);
 991  remove:
 992         list_del_init(&rfkill->node);
 993  unlock:
 994         mutex_unlock(&rfkill_global_mutex);
 995         return error;
 996 }
 997 EXPORT_SYMBOL(rfkill_register);
 998
 999 void rfkill_unregister(struct rfkill *rfkill)
1000 {
1001         BUG_ON(!rfkill);
1002
1003         if (rfkill->ops->poll)
1004                 cancel_delayed_work_sync(&rfkill->poll_work);
1005
1006         cancel_work_sync(&rfkill->uevent_work);
1007         cancel_work_sync(&rfkill->sync_work);
1008
1009         rfkill->registered = false;
1010
1011         device_del(&rfkill->dev);
1012
1013         mutex_lock(&rfkill_global_mutex);
1014         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1015         list_del_init(&rfkill->node);
1016         mutex_unlock(&rfkill_global_mutex);
1017
1018         rfkill_led_trigger_unregister(rfkill);
1019 }
1020 EXPORT_SYMBOL(rfkill_unregister);
1021
1022 void rfkill_destroy(struct rfkill *rfkill)
1023 {
1024         if (rfkill)
1025                 put_device(&rfkill->dev);
1026 }
1027 EXPORT_SYMBOL(rfkill_destroy);
1028
1029 static int rfkill_fop_open(struct inode *inode, struct file *file)
1030 {
1031         struct rfkill_data *data;
1032         struct rfkill *rfkill;
1033         struct rfkill_int_event *ev, *tmp;
1034
1035         data = kzalloc(sizeof(*data), GFP_KERNEL);
1036         if (!data)
1037                 return -ENOMEM;
1038
1039         INIT_LIST_HEAD(&data->events);
1040         mutex_init(&data->mtx);
1041         init_waitqueue_head(&data->read_wait);
1042
1043         mutex_lock(&rfkill_global_mutex);
1044         mutex_lock(&data->mtx);
1045         /*
1046          * start getting events from elsewhere but hold mtx to get
1047          * startup events added first
1048          */
1049
1050         list_for_each_entry(rfkill, &rfkill_list, node) {
1051                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1052                 if (!ev)
1053                         goto free;
1054                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1055                 list_add_tail(&ev->list, &data->events);
1056         }
1057         list_add(&data->list, &rfkill_fds);
1058         mutex_unlock(&data->mtx);
1059         mutex_unlock(&rfkill_global_mutex);
1060
1061         file->private_data = data;
1062
1063         return nonseekable_open(inode, file);
1064
1065  free:
1066         mutex_unlock(&data->mtx);
1067         mutex_unlock(&rfkill_global_mutex);
1068         mutex_destroy(&data->mtx);
1069         list_for_each_entry_safe(ev, tmp, &data->events, list)
1070                 kfree(ev);
1071         kfree(data);
1072         return -ENOMEM;
1073 }
1074
1075 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1076 {
1077         struct rfkill_data *data = file->private_data;
1078         unsigned int res = POLLOUT | POLLWRNORM;
1079
1080         poll_wait(file, &data->read_wait, wait);
1081
1082         mutex_lock(&data->mtx);
1083         if (!list_empty(&data->events))
1084                 res = POLLIN | POLLRDNORM;
1085         mutex_unlock(&data->mtx);
1086
1087         return res;
1088 }
1089
1090 static bool rfkill_readable(struct rfkill_data *data)
1091 {
1092         bool r;
1093
1094         mutex_lock(&data->mtx);
1095         r = !list_empty(&data->events);
1096         mutex_unlock(&data->mtx);
1097
1098         return r;
1099 }
1100
1101 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1102                                size_t count, loff_t *pos)
1103 {
1104         struct rfkill_data *data = file->private_data;
1105         struct rfkill_int_event *ev;
1106         unsigned long sz;
1107         int ret;
1108
1109         mutex_lock(&data->mtx);
1110
1111         while (list_empty(&data->events)) {
1112                 if (file->f_flags & O_NONBLOCK) {
1113                         ret = -EAGAIN;
1114                         goto out;
1115                 }
1116                 mutex_unlock(&data->mtx);
1117                 ret = wait_event_interruptible(data->read_wait,
1118                                                rfkill_readable(data));
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);