net/rfkill/core.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  * Copyright 2009 Johannes Berg <[email protected]>
   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         bool                    polling_paused;
  61         bool                    suspended;
  62
  63         const struct rfkill_ops *ops;
  64         void                    *data;
  65
  66 #ifdef CONFIG_RFKILL_LEDS
  67         struct led_trigger      led_trigger;
  68         const char              *ledtrigname;
  69 #endif
  70
  71         struct device           dev;
  72         struct list_head        node;
  73
  74         struct delayed_work     poll_work;
  75         struct work_struct      uevent_work;
  76         struct work_struct      sync_work;
  77         char                    name[];
  78 };
  79 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
  80
  81 struct rfkill_int_event {
  82         struct list_head        list;
  83         struct rfkill_event     ev;
  84 };
  85
  86 struct rfkill_data {
  87         struct list_head        list;
  88         struct list_head        events;
  89         struct mutex            mtx;
  90         wait_queue_head_t       read_wait;
  91         bool                    input_handler;
  92 };
  93
  94
  95 MODULE_AUTHOR("Ivo van Doorn <[email protected]>");
  96 MODULE_AUTHOR("Johannes Berg <[email protected]>");
  97 MODULE_DESCRIPTION("RF switch support");
  98 MODULE_LICENSE("GPL");
  99
 100
 101 /*
 102  * The locking here should be made much smarter, we currently have
 103  * a bit of a stupid situation because drivers might want to register
 104  * the rfkill struct under their own lock, and take this lock during
 105  * rfkill method calls -- which will cause an AB-BA deadlock situation.
 106  *
 107  * To fix that, we need to rework this code here to be mostly lock-free
 108  * and only use the mutex for list manipulations, not to protect the
 109  * various other global variables. Then we can avoid holding the mutex
 110  * around driver operations, and all is happy.
 111  */
 112 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 113 static DEFINE_MUTEX(rfkill_global_mutex);
 114 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 115
 116 static unsigned int rfkill_default_state = 1;
 117 module_param_named(default_state, rfkill_default_state, uint, 0444);
 118 MODULE_PARM_DESC(default_state,
 119                  "Default initial state for all radio types, 0 = radio off");
 120
 121 static struct {
 122         bool cur, sav;
 123 } rfkill_global_states[NUM_RFKILL_TYPES];
 124
 125 static bool rfkill_epo_lock_active;
 126
 127
 128 #ifdef CONFIG_RFKILL_LEDS
 129 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 130 {
 131         struct led_trigger *trigger;
 132
 133         if (!rfkill->registered)
 134                 return;
 135
 136         trigger = &rfkill->led_trigger;
 137
 138         if (rfkill->state & RFKILL_BLOCK_ANY)
 139                 led_trigger_event(trigger, LED_OFF);
 140         else
 141                 led_trigger_event(trigger, LED_FULL);
 142 }
 143
 144 static void rfkill_led_trigger_activate(struct led_classdev *led)
 145 {
 146         struct rfkill *rfkill;
 147
 148         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 149
 150         rfkill_led_trigger_event(rfkill);
 151 }
 152
 153 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 154 {
 155         return rfkill->led_trigger.name;
 156 }
 157 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 158
 159 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 160 {
 161         BUG_ON(!rfkill);
 162
 163         rfkill->ledtrigname = name;
 164 }
 165 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 166
 167 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 168 {
 169         rfkill->led_trigger.name = rfkill->ledtrigname
 170                                         ? : dev_name(&rfkill->dev);
 171         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 172         return led_trigger_register(&rfkill->led_trigger);
 173 }
 174
 175 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 176 {
 177         led_trigger_unregister(&rfkill->led_trigger);
 178 }
 179
 180 static struct led_trigger rfkill_any_led_trigger;
 181 static struct led_trigger rfkill_none_led_trigger;
 182 static struct work_struct rfkill_global_led_trigger_work;
 183
 184 static void rfkill_global_led_trigger_worker(struct work_struct *work)
 185 {
 186         enum led_brightness brightness = LED_OFF;
 187         struct rfkill *rfkill;
 188
 189         mutex_lock(&rfkill_global_mutex);
 190         list_for_each_entry(rfkill, &rfkill_list, node) {
 191                 if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
 192                         brightness = LED_FULL;
 193                         break;
 194                 }
 195         }
 196         mutex_unlock(&rfkill_global_mutex);
 197
 198         led_trigger_event(&rfkill_any_led_trigger, brightness);
 199         led_trigger_event(&rfkill_none_led_trigger,
 200                           brightness == LED_OFF ? LED_FULL : LED_OFF);
 201 }
 202
 203 static void rfkill_global_led_trigger_event(void)
 204 {
 205         schedule_work(&rfkill_global_led_trigger_work);
 206 }
 207
 208 static int rfkill_global_led_trigger_register(void)
 209 {
 210         int ret;
 211
 212         INIT_WORK(&rfkill_global_led_trigger_work,
 213                         rfkill_global_led_trigger_worker);
 214
 215         rfkill_any_led_trigger.name = "rfkill-any";
 216         ret = led_trigger_register(&rfkill_any_led_trigger);
 217         if (ret)
 218                 return ret;
 219
 220         rfkill_none_led_trigger.name = "rfkill-none";
 221         ret = led_trigger_register(&rfkill_none_led_trigger);
 222         if (ret)
 223                 led_trigger_unregister(&rfkill_any_led_trigger);
 224         else
 225                 /* Delay activation until all global triggers are registered */
 226                 rfkill_global_led_trigger_event();
 227
 228         return ret;
 229 }
 230
 231 static void rfkill_global_led_trigger_unregister(void)
 232 {
 233         led_trigger_unregister(&rfkill_none_led_trigger);
 234         led_trigger_unregister(&rfkill_any_led_trigger);
 235         cancel_work_sync(&rfkill_global_led_trigger_work);
 236 }
 237 #else
 238 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 239 {
 240 }
 241
 242 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 243 {
 244         return 0;
 245 }
 246
 247 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 248 {
 249 }
 250
 251 static void rfkill_global_led_trigger_event(void)
 252 {
 253 }
 254
 255 static int rfkill_global_led_trigger_register(void)
 256 {
 257         return 0;
 258 }
 259
 260 static void rfkill_global_led_trigger_unregister(void)
 261 {
 262 }
 263 #endif /* CONFIG_RFKILL_LEDS */
 264
 265 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 266                               enum rfkill_operation op)
 267 {
 268         unsigned long flags;
 269
 270         ev->idx = rfkill->idx;
 271         ev->type = rfkill->type;
 272         ev->op = op;
 273
 274         spin_lock_irqsave(&rfkill->lock, flags);
 275         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 276         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 277                                         RFKILL_BLOCK_SW_PREV));
 278         spin_unlock_irqrestore(&rfkill->lock, flags);
 279 }
 280
 281 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 282 {
 283         struct rfkill_data *data;
 284         struct rfkill_int_event *ev;
 285
 286         list_for_each_entry(data, &rfkill_fds, list) {
 287                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 288                 if (!ev)
 289                         continue;
 290                 rfkill_fill_event(&ev->ev, rfkill, op);
 291                 mutex_lock(&data->mtx);
 292                 list_add_tail(&ev->list, &data->events);
 293                 mutex_unlock(&data->mtx);
 294                 wake_up_interruptible(&data->read_wait);
 295         }
 296 }
 297
 298 static void rfkill_event(struct rfkill *rfkill)
 299 {
 300         if (!rfkill->registered)
 301                 return;
 302
 303         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 304
 305         /* also send event to /dev/rfkill */
 306         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 307 }
 308
 309 /**
 310  * rfkill_set_block - wrapper for set_block method
 311  *
 312  * @rfkill: the rfkill struct to use
 313  * @blocked: the new software state
 314  *
 315  * Calls the set_block method (when applicable) and handles notifications
 316  * etc. as well.
 317  */
 318 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 319 {
 320         unsigned long flags;
 321         bool prev, curr;
 322         int err;
 323
 324         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 325                 return;
 326
 327         /*
 328          * Some platforms (...!) generate input events which affect the
 329          * _hard_ kill state -- whenever something tries to change the
 330          * current software state query the hardware state too.
 331          */
 332         if (rfkill->ops->query)
 333                 rfkill->ops->query(rfkill, rfkill->data);
 334
 335         spin_lock_irqsave(&rfkill->lock, flags);
 336         prev = rfkill->state & RFKILL_BLOCK_SW;
 337
 338         if (prev)
 339                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 340         else
 341                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 342
 343         if (blocked)
 344                 rfkill->state |= RFKILL_BLOCK_SW;
 345         else
 346                 rfkill->state &= ~RFKILL_BLOCK_SW;
 347
 348         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 349         spin_unlock_irqrestore(&rfkill->lock, flags);
 350
 351         err = rfkill->ops->set_block(rfkill->data, blocked);
 352
 353         spin_lock_irqsave(&rfkill->lock, flags);
 354         if (err) {
 355                 /*
 356                  * Failed -- reset status to _PREV, which may be different
 357                  * from what we have set _PREV to earlier in this function
 358                  * if rfkill_set_sw_state was invoked.
 359                  */
 360                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 361                         rfkill->state |= RFKILL_BLOCK_SW;
 362                 else
 363                         rfkill->state &= ~RFKILL_BLOCK_SW;
 364         }
 365         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 366         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 367         curr = rfkill->state & RFKILL_BLOCK_SW;
 368         spin_unlock_irqrestore(&rfkill->lock, flags);
 369
 370         rfkill_led_trigger_event(rfkill);
 371         rfkill_global_led_trigger_event();
 372
 373         if (prev != curr)
 374                 rfkill_event(rfkill);
 375 }
 376
 377 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
 378 {
 379         int i;
 380
 381         if (type != RFKILL_TYPE_ALL) {
 382                 rfkill_global_states[type].cur = blocked;
 383                 return;
 384         }
 385
 386         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 387                 rfkill_global_states[i].cur = blocked;
 388 }
 389
 390 #ifdef CONFIG_RFKILL_INPUT
 391 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 392
 393 /**
 394  * __rfkill_switch_all - Toggle state of all switches of given type
 395  * @type: type of interfaces to be affected
 396  * @blocked: the new state
 397  *
 398  * This function sets the state of all switches of given type,
 399  * unless a specific switch is suspended.
 400  *
 401  * Caller must have acquired rfkill_global_mutex.
 402  */
 403 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 404 {
 405         struct rfkill *rfkill;
 406
 407         rfkill_update_global_state(type, blocked);
 408         list_for_each_entry(rfkill, &rfkill_list, node) {
 409                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 410                         continue;
 411
 412                 rfkill_set_block(rfkill, blocked);
 413         }
 414 }
 415
 416 /**
 417  * rfkill_switch_all - Toggle state of all switches of given type
 418  * @type: type of interfaces to be affected
 419  * @blocked: the new state
 420  *
 421  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 422  * Please refer to __rfkill_switch_all() for details.
 423  *
 424  * Does nothing if the EPO lock is active.
 425  */
 426 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 427 {
 428         if (atomic_read(&rfkill_input_disabled))
 429                 return;
 430
 431         mutex_lock(&rfkill_global_mutex);
 432
 433         if (!rfkill_epo_lock_active)
 434                 __rfkill_switch_all(type, blocked);
 435
 436         mutex_unlock(&rfkill_global_mutex);
 437 }
 438
 439 /**
 440  * rfkill_epo - emergency power off all transmitters
 441  *
 442  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 443  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 444  *
 445  * The global state before the EPO is saved and can be restored later
 446  * using rfkill_restore_states().
 447  */
 448 void rfkill_epo(void)
 449 {
 450         struct rfkill *rfkill;
 451         int i;
 452
 453         if (atomic_read(&rfkill_input_disabled))
 454                 return;
 455
 456         mutex_lock(&rfkill_global_mutex);
 457
 458         rfkill_epo_lock_active = true;
 459         list_for_each_entry(rfkill, &rfkill_list, node)
 460                 rfkill_set_block(rfkill, true);
 461
 462         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 463                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 464                 rfkill_global_states[i].cur = true;
 465         }
 466
 467         mutex_unlock(&rfkill_global_mutex);
 468 }
 469
 470 /**
 471  * rfkill_restore_states - restore global states
 472  *
 473  * Restore (and sync switches to) the global state from the
 474  * states in rfkill_default_states.  This can undo the effects of
 475  * a call to rfkill_epo().
 476  */
 477 void rfkill_restore_states(void)
 478 {
 479         int i;
 480
 481         if (atomic_read(&rfkill_input_disabled))
 482                 return;
 483
 484         mutex_lock(&rfkill_global_mutex);
 485
 486         rfkill_epo_lock_active = false;
 487         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 488                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 489         mutex_unlock(&rfkill_global_mutex);
 490 }
 491
 492 /**
 493  * rfkill_remove_epo_lock - unlock state changes
 494  *
 495  * Used by rfkill-input manually unlock state changes, when
 496  * the EPO switch is deactivated.
 497  */
 498 void rfkill_remove_epo_lock(void)
 499 {
 500         if (atomic_read(&rfkill_input_disabled))
 501                 return;
 502
 503         mutex_lock(&rfkill_global_mutex);
 504         rfkill_epo_lock_active = false;
 505         mutex_unlock(&rfkill_global_mutex);
 506 }
 507
 508 /**
 509  * rfkill_is_epo_lock_active - returns true EPO is active
 510  *
 511  * Returns 0 (false) if there is NOT an active EPO contidion,
 512  * and 1 (true) if there is an active EPO contition, which
 513  * locks all radios in one of the BLOCKED states.
 514  *
 515  * Can be called in atomic context.
 516  */
 517 bool rfkill_is_epo_lock_active(void)
 518 {
 519         return rfkill_epo_lock_active;
 520 }
 521
 522 /**
 523  * rfkill_get_global_sw_state - returns global state for a type
 524  * @type: the type to get the global state of
 525  *
 526  * Returns the current global state for a given wireless
 527  * device type.
 528  */
 529 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 530 {
 531         return rfkill_global_states[type].cur;
 532 }
 533 #endif
 534
 535 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 536 {
 537         unsigned long flags;
 538         bool ret, prev;
 539
 540         BUG_ON(!rfkill);
 541
 542         spin_lock_irqsave(&rfkill->lock, flags);
 543         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 544         if (blocked)
 545                 rfkill->state |= RFKILL_BLOCK_HW;
 546         else
 547                 rfkill->state &= ~RFKILL_BLOCK_HW;
 548         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
 549         spin_unlock_irqrestore(&rfkill->lock, flags);
 550
 551         rfkill_led_trigger_event(rfkill);
 552         rfkill_global_led_trigger_event();
 553
 554         if (rfkill->registered && prev != blocked)
 555                 schedule_work(&rfkill->uevent_work);
 556
 557         return ret;
 558 }
 559 EXPORT_SYMBOL(rfkill_set_hw_state);
 560
 561 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 562 {
 563         u32 bit = RFKILL_BLOCK_SW;
 564
 565         /* if in a ops->set_block right now, use other bit */
 566         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 567                 bit = RFKILL_BLOCK_SW_PREV;
 568
 569         if (blocked)
 570                 rfkill->state |= bit;
 571         else
 572                 rfkill->state &= ~bit;
 573 }
 574
 575 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 576 {
 577         unsigned long flags;
 578         bool prev, hwblock;
 579
 580         BUG_ON(!rfkill);
 581
 582         spin_lock_irqsave(&rfkill->lock, flags);
 583         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 584         __rfkill_set_sw_state(rfkill, blocked);
 585         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 586         blocked = blocked || hwblock;
 587         spin_unlock_irqrestore(&rfkill->lock, flags);
 588
 589         if (!rfkill->registered)
 590                 return blocked;
 591
 592         if (prev != blocked && !hwblock)
 593                 schedule_work(&rfkill->uevent_work);
 594
 595         rfkill_led_trigger_event(rfkill);
 596         rfkill_global_led_trigger_event();
 597
 598         return blocked;
 599 }
 600 EXPORT_SYMBOL(rfkill_set_sw_state);
 601
 602 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 603 {
 604         unsigned long flags;
 605
 606         BUG_ON(!rfkill);
 607         BUG_ON(rfkill->registered);
 608
 609         spin_lock_irqsave(&rfkill->lock, flags);
 610         __rfkill_set_sw_state(rfkill, blocked);
 611         rfkill->persistent = true;
 612         spin_unlock_irqrestore(&rfkill->lock, flags);
 613 }
 614 EXPORT_SYMBOL(rfkill_init_sw_state);
 615
 616 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 617 {
 618         unsigned long flags;
 619         bool swprev, hwprev;
 620
 621         BUG_ON(!rfkill);
 622
 623         spin_lock_irqsave(&rfkill->lock, flags);
 624
 625         /*
 626          * No need to care about prev/setblock ... this is for uevent only
 627          * and that will get triggered by rfkill_set_block anyway.
 628          */
 629         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 630         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 631         __rfkill_set_sw_state(rfkill, sw);
 632         if (hw)
 633                 rfkill->state |= RFKILL_BLOCK_HW;
 634         else
 635                 rfkill->state &= ~RFKILL_BLOCK_HW;
 636
 637         spin_unlock_irqrestore(&rfkill->lock, flags);
 638
 639         if (!rfkill->registered) {
 640                 rfkill->persistent = true;
 641         } else {
 642                 if (swprev != sw || hwprev != hw)
 643                         schedule_work(&rfkill->uevent_work);
 644
 645                 rfkill_led_trigger_event(rfkill);
 646                 rfkill_global_led_trigger_event();
 647         }
 648 }
 649 EXPORT_SYMBOL(rfkill_set_states);
 650
 651 static const char * const rfkill_types[] = {
 652         NULL, /* RFKILL_TYPE_ALL */
 653         "wlan",
 654         "bluetooth",
 655         "ultrawideband",
 656         "wimax",
 657         "wwan",
 658         "gps",
 659         "fm",
 660         "nfc",
 661 };
 662
 663 enum rfkill_type rfkill_find_type(const char *name)
 664 {
 665         int i;
 666
 667         BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
 668
 669         if (!name)
 670                 return RFKILL_TYPE_ALL;
 671
 672         for (i = 1; i < NUM_RFKILL_TYPES; i++)
 673                 if (!strcmp(name, rfkill_types[i]))
 674                         return i;
 675         return RFKILL_TYPE_ALL;
 676 }
 677 EXPORT_SYMBOL(rfkill_find_type);
 678
 679 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 680                          char *buf)
 681 {
 682         struct rfkill *rfkill = to_rfkill(dev);
 683
 684         return sprintf(buf, "%s\n", rfkill->name);
 685 }
 686 static DEVICE_ATTR_RO(name);
 687
 688 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 689                          char *buf)
 690 {
 691         struct rfkill *rfkill = to_rfkill(dev);
 692
 693         return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
 694 }
 695 static DEVICE_ATTR_RO(type);
 696
 697 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 698                           char *buf)
 699 {
 700         struct rfkill *rfkill = to_rfkill(dev);
 701
 702         return sprintf(buf, "%d\n", rfkill->idx);
 703 }
 704 static DEVICE_ATTR_RO(index);
 705
 706 static ssize_t persistent_show(struct device *dev,
 707                                struct device_attribute *attr, char *buf)
 708 {
 709         struct rfkill *rfkill = to_rfkill(dev);
 710
 711         return sprintf(buf, "%d\n", rfkill->persistent);
 712 }
 713 static DEVICE_ATTR_RO(persistent);
 714
 715 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 716                          char *buf)
 717 {
 718         struct rfkill *rfkill = to_rfkill(dev);
 719
 720         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 721 }
 722 static DEVICE_ATTR_RO(hard);
 723
 724 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 725                          char *buf)
 726 {
 727         struct rfkill *rfkill = to_rfkill(dev);
 728
 729         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 730 }
 731
 732 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 733                           const char *buf, size_t count)
 734 {
 735         struct rfkill *rfkill = to_rfkill(dev);
 736         unsigned long state;
 737         int err;
 738
 739         if (!capable(CAP_NET_ADMIN))
 740                 return -EPERM;
 741
 742         err = kstrtoul(buf, 0, &state);
 743         if (err)
 744                 return err;
 745
 746         if (state > 1 )
 747                 return -EINVAL;
 748
 749         mutex_lock(&rfkill_global_mutex);
 750         rfkill_set_block(rfkill, state);
 751         mutex_unlock(&rfkill_global_mutex);
 752
 753         return count;
 754 }
 755 static DEVICE_ATTR_RW(soft);
 756
 757 static u8 user_state_from_blocked(unsigned long state)
 758 {
 759         if (state & RFKILL_BLOCK_HW)
 760                 return RFKILL_USER_STATE_HARD_BLOCKED;
 761         if (state & RFKILL_BLOCK_SW)
 762                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 763
 764         return RFKILL_USER_STATE_UNBLOCKED;
 765 }
 766
 767 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 768                           char *buf)
 769 {
 770         struct rfkill *rfkill = to_rfkill(dev);
 771
 772         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 773 }
 774
 775 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 776                            const char *buf, size_t count)
 777 {
 778         struct rfkill *rfkill = to_rfkill(dev);
 779         unsigned long state;
 780         int err;
 781
 782         if (!capable(CAP_NET_ADMIN))
 783                 return -EPERM;
 784
 785         err = kstrtoul(buf, 0, &state);
 786         if (err)
 787                 return err;
 788
 789         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 790             state != RFKILL_USER_STATE_UNBLOCKED)
 791                 return -EINVAL;
 792
 793         mutex_lock(&rfkill_global_mutex);
 794         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 795         mutex_unlock(&rfkill_global_mutex);
 796
 797         return count;
 798 }
 799 static DEVICE_ATTR_RW(state);
 800
 801 static struct attribute *rfkill_dev_attrs[] = {
 802         &dev_attr_name.attr,
 803         &dev_attr_type.attr,
 804         &dev_attr_index.attr,
 805         &dev_attr_persistent.attr,
 806         &dev_attr_state.attr,
 807         &dev_attr_soft.attr,
 808         &dev_attr_hard.attr,
 809         NULL,
 810 };
 811 ATTRIBUTE_GROUPS(rfkill_dev);
 812
 813 static void rfkill_release(struct device *dev)
 814 {
 815         struct rfkill *rfkill = to_rfkill(dev);
 816
 817         kfree(rfkill);
 818 }
 819
 820 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 821 {
 822         struct rfkill *rfkill = to_rfkill(dev);
 823         unsigned long flags;
 824         u32 state;
 825         int error;
 826
 827         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 828         if (error)
 829                 return error;
 830         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 831                                rfkill_types[rfkill->type]);
 832         if (error)
 833                 return error;
 834         spin_lock_irqsave(&rfkill->lock, flags);
 835         state = rfkill->state;
 836         spin_unlock_irqrestore(&rfkill->lock, flags);
 837         error = add_uevent_var(env, "RFKILL_STATE=%d",
 838                                user_state_from_blocked(state));
 839         return error;
 840 }
 841
 842 void rfkill_pause_polling(struct rfkill *rfkill)
 843 {
 844         BUG_ON(!rfkill);
 845
 846         if (!rfkill->ops->poll)
 847                 return;
 848
 849         rfkill->polling_paused = true;
 850         cancel_delayed_work_sync(&rfkill->poll_work);
 851 }
 852 EXPORT_SYMBOL(rfkill_pause_polling);
 853
 854 void rfkill_resume_polling(struct rfkill *rfkill)
 855 {
 856         BUG_ON(!rfkill);
 857
 858         if (!rfkill->ops->poll)
 859                 return;
 860
 861         rfkill->polling_paused = false;
 862
 863         if (rfkill->suspended)
 864                 return;
 865
 866         queue_delayed_work(system_power_efficient_wq,
 867                            &rfkill->poll_work, 0);
 868 }
 869 EXPORT_SYMBOL(rfkill_resume_polling);
 870
 871 #ifdef CONFIG_PM_SLEEP
 872 static int rfkill_suspend(struct device *dev)
 873 {
 874         struct rfkill *rfkill = to_rfkill(dev);
 875
 876         rfkill->suspended = true;
 877         cancel_delayed_work_sync(&rfkill->poll_work);
 878
 879         return 0;
 880 }
 881
 882 static int rfkill_resume(struct device *dev)
 883 {
 884         struct rfkill *rfkill = to_rfkill(dev);
 885         bool cur;
 886
 887         rfkill->suspended = false;
 888
 889         if (!rfkill->persistent) {
 890                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 891                 rfkill_set_block(rfkill, cur);
 892         }
 893
 894         if (rfkill->ops->poll && !rfkill->polling_paused)
 895                 queue_delayed_work(system_power_efficient_wq,
 896                                    &rfkill->poll_work, 0);
 897
 898         return 0;
 899 }
 900
 901 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 902 #define RFKILL_PM_OPS (&rfkill_pm_ops)
 903 #else
 904 #define RFKILL_PM_OPS NULL
 905 #endif
 906
 907 static struct class rfkill_class = {
 908         .name           = "rfkill",
 909         .dev_release    = rfkill_release,
 910         .dev_groups     = rfkill_dev_groups,
 911         .dev_uevent     = rfkill_dev_uevent,
 912         .pm             = RFKILL_PM_OPS,
 913 };
 914
 915 bool rfkill_blocked(struct rfkill *rfkill)
 916 {
 917         unsigned long flags;
 918         u32 state;
 919
 920         spin_lock_irqsave(&rfkill->lock, flags);
 921         state = rfkill->state;
 922         spin_unlock_irqrestore(&rfkill->lock, flags);
 923
 924         return !!(state & RFKILL_BLOCK_ANY);
 925 }
 926 EXPORT_SYMBOL(rfkill_blocked);
 927
 928
 929 struct rfkill * __must_check rfkill_alloc(const char *name,
 930                                           struct device *parent,
 931                                           const enum rfkill_type type,
 932                                           const struct rfkill_ops *ops,
 933                                           void *ops_data)
 934 {
 935         struct rfkill *rfkill;
 936         struct device *dev;
 937
 938         if (WARN_ON(!ops))
 939                 return NULL;
 940
 941         if (WARN_ON(!ops->set_block))
 942                 return NULL;
 943
 944         if (WARN_ON(!name))
 945                 return NULL;
 946
 947         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 948                 return NULL;
 949
 950         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 951         if (!rfkill)
 952                 return NULL;
 953
 954         spin_lock_init(&rfkill->lock);
 955         INIT_LIST_HEAD(&rfkill->node);
 956         rfkill->type = type;
 957         strcpy(rfkill->name, name);
 958         rfkill->ops = ops;
 959         rfkill->data = ops_data;
 960
 961         dev = &rfkill->dev;
 962         dev->class = &rfkill_class;
 963         dev->parent = parent;
 964         device_initialize(dev);
 965
 966         return rfkill;
 967 }
 968 EXPORT_SYMBOL(rfkill_alloc);
 969
 970 static void rfkill_poll(struct work_struct *work)
 971 {
 972         struct rfkill *rfkill;
 973
 974         rfkill = container_of(work, struct rfkill, poll_work.work);
 975
 976         /*
 977          * Poll hardware state -- driver will use one of the
 978          * rfkill_set{,_hw,_sw}_state functions and use its
 979          * return value to update the current status.
 980          */
 981         rfkill->ops->poll(rfkill, rfkill->data);
 982
 983         queue_delayed_work(system_power_efficient_wq,
 984                 &rfkill->poll_work,
 985                 round_jiffies_relative(POLL_INTERVAL));
 986 }
 987
 988 static void rfkill_uevent_work(struct work_struct *work)
 989 {
 990         struct rfkill *rfkill;
 991
 992         rfkill = container_of(work, struct rfkill, uevent_work);
 993
 994         mutex_lock(&rfkill_global_mutex);
 995         rfkill_event(rfkill);
 996         mutex_unlock(&rfkill_global_mutex);
 997 }
 998
 999 static void rfkill_sync_work(struct work_struct *work)
1000 {
1001         struct rfkill *rfkill;
1002         bool cur;
1003
1004         rfkill = container_of(work, struct rfkill, sync_work);
1005
1006         mutex_lock(&rfkill_global_mutex);
1007         cur = rfkill_global_states[rfkill->type].cur;
1008         rfkill_set_block(rfkill, cur);
1009         mutex_unlock(&rfkill_global_mutex);
1010 }
1011
1012 int __must_check rfkill_register(struct rfkill *rfkill)
1013 {
1014         static unsigned long rfkill_no;
1015         struct device *dev = &rfkill->dev;
1016         int error;
1017
1018         BUG_ON(!rfkill);
1019
1020         mutex_lock(&rfkill_global_mutex);
1021
1022         if (rfkill->registered) {
1023                 error = -EALREADY;
1024                 goto unlock;
1025         }
1026
1027         rfkill->idx = rfkill_no;
1028         dev_set_name(dev, "rfkill%lu", rfkill_no);
1029         rfkill_no++;
1030
1031         list_add_tail(&rfkill->node, &rfkill_list);
1032
1033         error = device_add(dev);
1034         if (error)
1035                 goto remove;
1036
1037         error = rfkill_led_trigger_register(rfkill);
1038         if (error)
1039                 goto devdel;
1040
1041         rfkill->registered = true;
1042
1043         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
1044         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
1045         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
1046
1047         if (rfkill->ops->poll)
1048                 queue_delayed_work(system_power_efficient_wq,
1049                         &rfkill->poll_work,
1050                         round_jiffies_relative(POLL_INTERVAL));
1051
1052         if (!rfkill->persistent || rfkill_epo_lock_active) {
1053                 schedule_work(&rfkill->sync_work);
1054         } else {
1055 #ifdef CONFIG_RFKILL_INPUT
1056                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
1057
1058                 if (!atomic_read(&rfkill_input_disabled))
1059                         __rfkill_switch_all(rfkill->type, soft_blocked);
1060 #endif
1061         }
1062
1063         rfkill_global_led_trigger_event();
1064         rfkill_send_events(rfkill, RFKILL_OP_ADD);
1065
1066         mutex_unlock(&rfkill_global_mutex);
1067         return 0;
1068
1069  devdel:
1070         device_del(&rfkill->dev);
1071  remove:
1072         list_del_init(&rfkill->node);
1073  unlock:
1074         mutex_unlock(&rfkill_global_mutex);
1075         return error;
1076 }
1077 EXPORT_SYMBOL(rfkill_register);
1078
1079 void rfkill_unregister(struct rfkill *rfkill)
1080 {
1081         BUG_ON(!rfkill);
1082
1083         if (rfkill->ops->poll)
1084                 cancel_delayed_work_sync(&rfkill->poll_work);
1085
1086         cancel_work_sync(&rfkill->uevent_work);
1087         cancel_work_sync(&rfkill->sync_work);
1088
1089         rfkill->registered = false;
1090
1091         device_del(&rfkill->dev);
1092
1093         mutex_lock(&rfkill_global_mutex);
1094         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1095         list_del_init(&rfkill->node);
1096         rfkill_global_led_trigger_event();
1097         mutex_unlock(&rfkill_global_mutex);
1098
1099         rfkill_led_trigger_unregister(rfkill);
1100 }
1101 EXPORT_SYMBOL(rfkill_unregister);
1102
1103 void rfkill_destroy(struct rfkill *rfkill)
1104 {
1105         if (rfkill)
1106                 put_device(&rfkill->dev);
1107 }
1108 EXPORT_SYMBOL(rfkill_destroy);
1109
1110 static int rfkill_fop_open(struct inode *inode, struct file *file)
1111 {
1112         struct rfkill_data *data;
1113         struct rfkill *rfkill;
1114         struct rfkill_int_event *ev, *tmp;
1115
1116         data = kzalloc(sizeof(*data), GFP_KERNEL);
1117         if (!data)
1118                 return -ENOMEM;
1119
1120         INIT_LIST_HEAD(&data->events);
1121         mutex_init(&data->mtx);
1122         init_waitqueue_head(&data->read_wait);
1123
1124         mutex_lock(&rfkill_global_mutex);
1125         mutex_lock(&data->mtx);
1126         /*
1127          * start getting events from elsewhere but hold mtx to get
1128          * startup events added first
1129          */
1130
1131         list_for_each_entry(rfkill, &rfkill_list, node) {
1132                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1133                 if (!ev)
1134                         goto free;
1135                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1136                 list_add_tail(&ev->list, &data->events);
1137         }
1138         list_add(&data->list, &rfkill_fds);
1139         mutex_unlock(&data->mtx);
1140         mutex_unlock(&rfkill_global_mutex);
1141
1142         file->private_data = data;
1143
1144         return nonseekable_open(inode, file);
1145
1146  free:
1147         mutex_unlock(&data->mtx);
1148         mutex_unlock(&rfkill_global_mutex);
1149         mutex_destroy(&data->mtx);
1150         list_for_each_entry_safe(ev, tmp, &data->events, list)
1151                 kfree(ev);
1152         kfree(data);
1153         return -ENOMEM;
1154 }
1155
1156 static __poll_t rfkill_fop_poll(struct file *file, poll_table *wait)
1157 {
1158         struct rfkill_data *data = file->private_data;
1159         __poll_t res = EPOLLOUT | EPOLLWRNORM;
1160
1161         poll_wait(file, &data->read_wait, wait);
1162
1163         mutex_lock(&data->mtx);
1164         if (!list_empty(&data->events))
1165                 res = EPOLLIN | EPOLLRDNORM;
1166         mutex_unlock(&data->mtx);
1167
1168         return res;
1169 }
1170
1171 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1172                                size_t count, loff_t *pos)
1173 {
1174         struct rfkill_data *data = file->private_data;
1175         struct rfkill_int_event *ev;
1176         unsigned long sz;
1177         int ret;
1178
1179         mutex_lock(&data->mtx);
1180
1181         while (list_empty(&data->events)) {
1182                 if (file->f_flags & O_NONBLOCK) {
1183                         ret = -EAGAIN;
1184                         goto out;
1185                 }
1186                 mutex_unlock(&data->mtx);
1187                 /* since we re-check and it just compares pointers,
1188                  * using !list_empty() without locking isn't a problem
1189                  */
1190                 ret = wait_event_interruptible(data->read_wait,
1191                                                !list_empty(&data->events));
1192                 mutex_lock(&data->mtx);
1193
1194                 if (ret)
1195                         goto out;
1196         }
1197
1198         ev = list_first_entry(&data->events, struct rfkill_int_event,
1199                                 list);
1200
1201         sz = min_t(unsigned long, sizeof(ev->ev), count);
1202         ret = sz;
1203         if (copy_to_user(buf, &ev->ev, sz))
1204                 ret = -EFAULT;
1205
1206         list_del(&ev->list);
1207         kfree(ev);
1208  out:
1209         mutex_unlock(&data->mtx);
1210         return ret;
1211 }
1212
1213 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1214                                 size_t count, loff_t *pos)
1215 {
1216         struct rfkill *rfkill;
1217         struct rfkill_event ev;
1218         int ret;
1219
1220         /* we don't need the 'hard' variable but accept it */
1221         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1222                 return -EINVAL;
1223
1224         /*
1225          * Copy as much data as we can accept into our 'ev' buffer,
1226          * but tell userspace how much we've copied so it can determine
1227          * our API version even in a write() call, if it cares.
1228          */
1229         count = min(count, sizeof(ev));
1230         if (copy_from_user(&ev, buf, count))
1231                 return -EFAULT;
1232
1233         if (ev.type >= NUM_RFKILL_TYPES)
1234                 return -EINVAL;
1235
1236         mutex_lock(&rfkill_global_mutex);
1237
1238         switch (ev.op) {
1239         case RFKILL_OP_CHANGE_ALL:
1240                 rfkill_update_global_state(ev.type, ev.soft);
1241                 list_for_each_entry(rfkill, &rfkill_list, node)
1242                         if (rfkill->type == ev.type ||
1243                             ev.type == RFKILL_TYPE_ALL)
1244                                 rfkill_set_block(rfkill, ev.soft);
1245                 ret = 0;
1246                 break;
1247         case RFKILL_OP_CHANGE:
1248                 list_for_each_entry(rfkill, &rfkill_list, node)
1249                         if (rfkill->idx == ev.idx &&
1250                             (rfkill->type == ev.type ||
1251                              ev.type == RFKILL_TYPE_ALL))
1252                                 rfkill_set_block(rfkill, ev.soft);
1253                 ret = 0;
1254                 break;
1255         default:
1256                 ret = -EINVAL;
1257                 break;
1258         }
1259
1260         mutex_unlock(&rfkill_global_mutex);
1261
1262         return ret ?: count;
1263 }
1264
1265 static int rfkill_fop_release(struct inode *inode, struct file *file)
1266 {
1267         struct rfkill_data *data = file->private_data;
1268         struct rfkill_int_event *ev, *tmp;
1269
1270         mutex_lock(&rfkill_global_mutex);
1271         list_del(&data->list);
1272         mutex_unlock(&rfkill_global_mutex);
1273
1274         mutex_destroy(&data->mtx);
1275         list_for_each_entry_safe(ev, tmp, &data->events, list)
1276                 kfree(ev);
1277
1278 #ifdef CONFIG_RFKILL_INPUT
1279         if (data->input_handler)
1280                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1281                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1282 #endif
1283
1284         kfree(data);
1285
1286         return 0;
1287 }
1288
1289 #ifdef CONFIG_RFKILL_INPUT
1290 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1291                              unsigned long arg)
1292 {
1293         struct rfkill_data *data = file->private_data;
1294
1295         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1296                 return -ENOSYS;
1297
1298         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1299                 return -ENOSYS;
1300
1301         mutex_lock(&data->mtx);
1302
1303         if (!data->input_handler) {
1304                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1305                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1306                 data->input_handler = true;
1307         }
1308
1309         mutex_unlock(&data->mtx);
1310
1311         return 0;
1312 }
1313 #endif
1314
1315 static const struct file_operations rfkill_fops = {
1316         .owner          = THIS_MODULE,
1317         .open           = rfkill_fop_open,
1318         .read           = rfkill_fop_read,
1319         .write          = rfkill_fop_write,
1320         .poll           = rfkill_fop_poll,
1321         .release        = rfkill_fop_release,
1322 #ifdef CONFIG_RFKILL_INPUT
1323         .unlocked_ioctl = rfkill_fop_ioctl,
1324         .compat_ioctl   = rfkill_fop_ioctl,
1325 #endif
1326         .llseek         = no_llseek,
1327 };
1328
1329 static struct miscdevice rfkill_miscdev = {
1330         .name   = "rfkill",
1331         .fops   = &rfkill_fops,
1332         .minor  = MISC_DYNAMIC_MINOR,
1333 };
1334
1335 static int __init rfkill_init(void)
1336 {
1337         int error;
1338
1339         rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1340
1341         error = class_register(&rfkill_class);
1342         if (error)
1343                 goto error_class;
1344
1345         error = misc_register(&rfkill_miscdev);
1346         if (error)
1347                 goto error_misc;
1348
1349         error = rfkill_global_led_trigger_register();
1350         if (error)
1351                 goto error_led_trigger;
1352
1353 #ifdef CONFIG_RFKILL_INPUT
1354         error = rfkill_handler_init();
1355         if (error)
1356                 goto error_input;
1357 #endif
1358
1359         return 0;
1360
1361 #ifdef CONFIG_RFKILL_INPUT
1362 error_input:
1363         rfkill_global_led_trigger_unregister();
1364 #endif
1365 error_led_trigger:
1366         misc_deregister(&rfkill_miscdev);
1367 error_misc:
1368         class_unregister(&rfkill_class);
1369 error_class:
1370         return error;
1371 }
1372 subsys_initcall(rfkill_init);
1373
1374 static void __exit rfkill_exit(void)
1375 {
1376 #ifdef CONFIG_RFKILL_INPUT
1377         rfkill_handler_exit();
1378 #endif
1379         rfkill_global_led_trigger_unregister();
1380         misc_deregister(&rfkill_miscdev);
1381         class_unregister(&rfkill_class);
1382 }
1383 module_exit(rfkill_exit);