net/rfkill/core.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the
  18  * Free Software Foundation, Inc.,
  19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/capability.h>
  27 #include <linux/list.h>
  28 #include <linux/mutex.h>
  29 #include <linux/rfkill.h>
  30 #include <linux/sched.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/miscdevice.h>
  33 #include <linux/wait.h>
  34 #include <linux/poll.h>
  35 #include <linux/fs.h>
  36
  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         int err;
 272
 273         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 274                 return;
 275
 276         /*
 277          * Some platforms (...!) generate input events which affect the
 278          * _hard_ kill state -- whenever something tries to change the
 279          * current software state query the hardware state too.
 280          */
 281         if (rfkill->ops->query)
 282                 rfkill->ops->query(rfkill, rfkill->data);
 283
 284         spin_lock_irqsave(&rfkill->lock, flags);
 285         if (rfkill->state & RFKILL_BLOCK_SW)
 286                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 287         else
 288                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 289
 290         if (blocked)
 291                 rfkill->state |= RFKILL_BLOCK_SW;
 292         else
 293                 rfkill->state &= ~RFKILL_BLOCK_SW;
 294
 295         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 296         spin_unlock_irqrestore(&rfkill->lock, flags);
 297
 298         err = rfkill->ops->set_block(rfkill->data, blocked);
 299
 300         spin_lock_irqsave(&rfkill->lock, flags);
 301         if (err) {
 302                 /*
 303                  * Failed -- reset status to _prev, this may be different
 304                  * from what set set _PREV to earlier in this function
 305                  * if rfkill_set_sw_state was invoked.
 306                  */
 307                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 308                         rfkill->state |= RFKILL_BLOCK_SW;
 309                 else
 310                         rfkill->state &= ~RFKILL_BLOCK_SW;
 311         }
 312         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 313         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 314         spin_unlock_irqrestore(&rfkill->lock, flags);
 315
 316         rfkill_led_trigger_event(rfkill);
 317         rfkill_event(rfkill);
 318 }
 319
 320 #ifdef CONFIG_RFKILL_INPUT
 321 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 322
 323 /**
 324  * __rfkill_switch_all - Toggle state of all switches of given type
 325  * @type: type of interfaces to be affected
 326  * @state: the new state
 327  *
 328  * This function sets the state of all switches of given type,
 329  * unless a specific switch is claimed by userspace (in which case,
 330  * that switch is left alone) or suspended.
 331  *
 332  * Caller must have acquired rfkill_global_mutex.
 333  */
 334 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 335 {
 336         struct rfkill *rfkill;
 337
 338         rfkill_global_states[type].cur = blocked;
 339         list_for_each_entry(rfkill, &rfkill_list, node) {
 340                 if (rfkill->type != type)
 341                         continue;
 342
 343                 rfkill_set_block(rfkill, blocked);
 344         }
 345 }
 346
 347 /**
 348  * rfkill_switch_all - Toggle state of all switches of given type
 349  * @type: type of interfaces to be affected
 350  * @state: the new state
 351  *
 352  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 353  * Please refer to __rfkill_switch_all() for details.
 354  *
 355  * Does nothing if the EPO lock is active.
 356  */
 357 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 358 {
 359         if (atomic_read(&rfkill_input_disabled))
 360                 return;
 361
 362         mutex_lock(&rfkill_global_mutex);
 363
 364         if (!rfkill_epo_lock_active)
 365                 __rfkill_switch_all(type, blocked);
 366
 367         mutex_unlock(&rfkill_global_mutex);
 368 }
 369
 370 /**
 371  * rfkill_epo - emergency power off all transmitters
 372  *
 373  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 374  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 375  *
 376  * The global state before the EPO is saved and can be restored later
 377  * using rfkill_restore_states().
 378  */
 379 void rfkill_epo(void)
 380 {
 381         struct rfkill *rfkill;
 382         int i;
 383
 384         if (atomic_read(&rfkill_input_disabled))
 385                 return;
 386
 387         mutex_lock(&rfkill_global_mutex);
 388
 389         rfkill_epo_lock_active = true;
 390         list_for_each_entry(rfkill, &rfkill_list, node)
 391                 rfkill_set_block(rfkill, true);
 392
 393         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 394                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 395                 rfkill_global_states[i].cur = true;
 396         }
 397
 398         mutex_unlock(&rfkill_global_mutex);
 399 }
 400
 401 /**
 402  * rfkill_restore_states - restore global states
 403  *
 404  * Restore (and sync switches to) the global state from the
 405  * states in rfkill_default_states.  This can undo the effects of
 406  * a call to rfkill_epo().
 407  */
 408 void rfkill_restore_states(void)
 409 {
 410         int i;
 411
 412         if (atomic_read(&rfkill_input_disabled))
 413                 return;
 414
 415         mutex_lock(&rfkill_global_mutex);
 416
 417         rfkill_epo_lock_active = false;
 418         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 419                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 420         mutex_unlock(&rfkill_global_mutex);
 421 }
 422
 423 /**
 424  * rfkill_remove_epo_lock - unlock state changes
 425  *
 426  * Used by rfkill-input manually unlock state changes, when
 427  * the EPO switch is deactivated.
 428  */
 429 void rfkill_remove_epo_lock(void)
 430 {
 431         if (atomic_read(&rfkill_input_disabled))
 432                 return;
 433
 434         mutex_lock(&rfkill_global_mutex);
 435         rfkill_epo_lock_active = false;
 436         mutex_unlock(&rfkill_global_mutex);
 437 }
 438
 439 /**
 440  * rfkill_is_epo_lock_active - returns true EPO is active
 441  *
 442  * Returns 0 (false) if there is NOT an active EPO contidion,
 443  * and 1 (true) if there is an active EPO contition, which
 444  * locks all radios in one of the BLOCKED states.
 445  *
 446  * Can be called in atomic context.
 447  */
 448 bool rfkill_is_epo_lock_active(void)
 449 {
 450         return rfkill_epo_lock_active;
 451 }
 452
 453 /**
 454  * rfkill_get_global_sw_state - returns global state for a type
 455  * @type: the type to get the global state of
 456  *
 457  * Returns the current global state for a given wireless
 458  * device type.
 459  */
 460 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 461 {
 462         return rfkill_global_states[type].cur;
 463 }
 464 #endif
 465
 466
 467 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 468 {
 469         bool ret, change;
 470
 471         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 472
 473         if (!rfkill->registered)
 474                 return ret;
 475
 476         if (change)
 477                 schedule_work(&rfkill->uevent_work);
 478
 479         return ret;
 480 }
 481 EXPORT_SYMBOL(rfkill_set_hw_state);
 482
 483 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 484 {
 485         u32 bit = RFKILL_BLOCK_SW;
 486
 487         /* if in a ops->set_block right now, use other bit */
 488         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 489                 bit = RFKILL_BLOCK_SW_PREV;
 490
 491         if (blocked)
 492                 rfkill->state |= bit;
 493         else
 494                 rfkill->state &= ~bit;
 495 }
 496
 497 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 498 {
 499         unsigned long flags;
 500         bool prev, hwblock;
 501
 502         BUG_ON(!rfkill);
 503
 504         spin_lock_irqsave(&rfkill->lock, flags);
 505         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 506         __rfkill_set_sw_state(rfkill, blocked);
 507         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 508         blocked = blocked || hwblock;
 509         spin_unlock_irqrestore(&rfkill->lock, flags);
 510
 511         if (!rfkill->registered)
 512                 return blocked;
 513
 514         if (prev != blocked && !hwblock)
 515                 schedule_work(&rfkill->uevent_work);
 516
 517         rfkill_led_trigger_event(rfkill);
 518
 519         return blocked;
 520 }
 521 EXPORT_SYMBOL(rfkill_set_sw_state);
 522
 523 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 524 {
 525         unsigned long flags;
 526
 527         BUG_ON(!rfkill);
 528         BUG_ON(rfkill->registered);
 529
 530         spin_lock_irqsave(&rfkill->lock, flags);
 531         __rfkill_set_sw_state(rfkill, blocked);
 532         rfkill->persistent = true;
 533         spin_unlock_irqrestore(&rfkill->lock, flags);
 534 }
 535 EXPORT_SYMBOL(rfkill_init_sw_state);
 536
 537 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 538 {
 539         unsigned long flags;
 540         bool swprev, hwprev;
 541
 542         BUG_ON(!rfkill);
 543
 544         spin_lock_irqsave(&rfkill->lock, flags);
 545
 546         /*
 547          * No need to care about prev/setblock ... this is for uevent only
 548          * and that will get triggered by rfkill_set_block anyway.
 549          */
 550         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 551         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 552         __rfkill_set_sw_state(rfkill, sw);
 553         if (hw)
 554                 rfkill->state |= RFKILL_BLOCK_HW;
 555         else
 556                 rfkill->state &= ~RFKILL_BLOCK_HW;
 557
 558         spin_unlock_irqrestore(&rfkill->lock, flags);
 559
 560         if (!rfkill->registered) {
 561                 rfkill->persistent = true;
 562         } else {
 563                 if (swprev != sw || hwprev != hw)
 564                         schedule_work(&rfkill->uevent_work);
 565
 566                 rfkill_led_trigger_event(rfkill);
 567         }
 568 }
 569 EXPORT_SYMBOL(rfkill_set_states);
 570
 571 static ssize_t rfkill_name_show(struct device *dev,
 572                                 struct device_attribute *attr,
 573                                 char *buf)
 574 {
 575         struct rfkill *rfkill = to_rfkill(dev);
 576
 577         return sprintf(buf, "%s\n", rfkill->name);
 578 }
 579
 580 static const char *rfkill_get_type_str(enum rfkill_type type)
 581 {
 582         switch (type) {
 583         case RFKILL_TYPE_WLAN:
 584                 return "wlan";
 585         case RFKILL_TYPE_BLUETOOTH:
 586                 return "bluetooth";
 587         case RFKILL_TYPE_UWB:
 588                 return "ultrawideband";
 589         case RFKILL_TYPE_WIMAX:
 590                 return "wimax";
 591         case RFKILL_TYPE_WWAN:
 592                 return "wwan";
 593         case RFKILL_TYPE_GPS:
 594                 return "gps";
 595         default:
 596                 BUG();
 597         }
 598
 599         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_GPS + 1);
 600 }
 601
 602 static ssize_t rfkill_type_show(struct device *dev,
 603                                 struct device_attribute *attr,
 604                                 char *buf)
 605 {
 606         struct rfkill *rfkill = to_rfkill(dev);
 607
 608         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 609 }
 610
 611 static ssize_t rfkill_idx_show(struct device *dev,
 612                                struct device_attribute *attr,
 613                                char *buf)
 614 {
 615         struct rfkill *rfkill = to_rfkill(dev);
 616
 617         return sprintf(buf, "%d\n", rfkill->idx);
 618 }
 619
 620 static ssize_t rfkill_persistent_show(struct device *dev,
 621                                struct device_attribute *attr,
 622                                char *buf)
 623 {
 624         struct rfkill *rfkill = to_rfkill(dev);
 625
 626         return sprintf(buf, "%d\n", rfkill->persistent);
 627 }
 628
 629 static u8 user_state_from_blocked(unsigned long state)
 630 {
 631         if (state & RFKILL_BLOCK_HW)
 632                 return RFKILL_USER_STATE_HARD_BLOCKED;
 633         if (state & RFKILL_BLOCK_SW)
 634                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 635
 636         return RFKILL_USER_STATE_UNBLOCKED;
 637 }
 638
 639 static ssize_t rfkill_state_show(struct device *dev,
 640                                  struct device_attribute *attr,
 641                                  char *buf)
 642 {
 643         struct rfkill *rfkill = to_rfkill(dev);
 644         unsigned long flags;
 645         u32 state;
 646
 647         spin_lock_irqsave(&rfkill->lock, flags);
 648         state = rfkill->state;
 649         spin_unlock_irqrestore(&rfkill->lock, flags);
 650
 651         return sprintf(buf, "%d\n", user_state_from_blocked(state));
 652 }
 653
 654 static ssize_t rfkill_state_store(struct device *dev,
 655                                   struct device_attribute *attr,
 656                                   const char *buf, size_t count)
 657 {
 658         struct rfkill *rfkill = to_rfkill(dev);
 659         unsigned long state;
 660         int err;
 661
 662         if (!capable(CAP_NET_ADMIN))
 663                 return -EPERM;
 664
 665         err = strict_strtoul(buf, 0, &state);
 666         if (err)
 667                 return err;
 668
 669         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 670             state != RFKILL_USER_STATE_UNBLOCKED)
 671                 return -EINVAL;
 672
 673         mutex_lock(&rfkill_global_mutex);
 674         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 675         mutex_unlock(&rfkill_global_mutex);
 676
 677         return err ?: count;
 678 }
 679
 680 static ssize_t rfkill_claim_show(struct device *dev,
 681                                  struct device_attribute *attr,
 682                                  char *buf)
 683 {
 684         return sprintf(buf, "%d\n", 0);
 685 }
 686
 687 static ssize_t rfkill_claim_store(struct device *dev,
 688                                   struct device_attribute *attr,
 689                                   const char *buf, size_t count)
 690 {
 691         return -EOPNOTSUPP;
 692 }
 693
 694 static struct device_attribute rfkill_dev_attrs[] = {
 695         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 696         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 697         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
 698         __ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
 699         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 700         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 701         __ATTR_NULL
 702 };
 703
 704 static void rfkill_release(struct device *dev)
 705 {
 706         struct rfkill *rfkill = to_rfkill(dev);
 707
 708         kfree(rfkill);
 709 }
 710
 711 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 712 {
 713         struct rfkill *rfkill = to_rfkill(dev);
 714         unsigned long flags;
 715         u32 state;
 716         int error;
 717
 718         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 719         if (error)
 720                 return error;
 721         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 722                                rfkill_get_type_str(rfkill->type));
 723         if (error)
 724                 return error;
 725         spin_lock_irqsave(&rfkill->lock, flags);
 726         state = rfkill->state;
 727         spin_unlock_irqrestore(&rfkill->lock, flags);
 728         error = add_uevent_var(env, "RFKILL_STATE=%d",
 729                                user_state_from_blocked(state));
 730         return error;
 731 }
 732
 733 void rfkill_pause_polling(struct rfkill *rfkill)
 734 {
 735         BUG_ON(!rfkill);
 736
 737         if (!rfkill->ops->poll)
 738                 return;
 739
 740         cancel_delayed_work_sync(&rfkill->poll_work);
 741 }
 742 EXPORT_SYMBOL(rfkill_pause_polling);
 743
 744 void rfkill_resume_polling(struct rfkill *rfkill)
 745 {
 746         BUG_ON(!rfkill);
 747
 748         if (!rfkill->ops->poll)
 749                 return;
 750
 751         schedule_work(&rfkill->poll_work.work);
 752 }
 753 EXPORT_SYMBOL(rfkill_resume_polling);
 754
 755 static int rfkill_suspend(struct device *dev, pm_message_t state)
 756 {
 757         struct rfkill *rfkill = to_rfkill(dev);
 758
 759         rfkill_pause_polling(rfkill);
 760
 761         return 0;
 762 }
 763
 764 static int rfkill_resume(struct device *dev)
 765 {
 766         struct rfkill *rfkill = to_rfkill(dev);
 767         bool cur;
 768
 769         if (!rfkill->persistent) {
 770                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 771                 rfkill_set_block(rfkill, cur);
 772         }
 773
 774         rfkill_resume_polling(rfkill);
 775
 776         return 0;
 777 }
 778
 779 static struct class rfkill_class = {
 780         .name           = "rfkill",
 781         .dev_release    = rfkill_release,
 782         .dev_attrs      = rfkill_dev_attrs,
 783         .dev_uevent     = rfkill_dev_uevent,
 784         .suspend        = rfkill_suspend,
 785         .resume         = rfkill_resume,
 786 };
 787
 788 bool rfkill_blocked(struct rfkill *rfkill)
 789 {
 790         unsigned long flags;
 791         u32 state;
 792
 793         spin_lock_irqsave(&rfkill->lock, flags);
 794         state = rfkill->state;
 795         spin_unlock_irqrestore(&rfkill->lock, flags);
 796
 797         return !!(state & RFKILL_BLOCK_ANY);
 798 }
 799 EXPORT_SYMBOL(rfkill_blocked);
 800
 801
 802 struct rfkill * __must_check rfkill_alloc(const char *name,
 803                                           struct device *parent,
 804                                           const enum rfkill_type type,
 805                                           const struct rfkill_ops *ops,
 806                                           void *ops_data)
 807 {
 808         struct rfkill *rfkill;
 809         struct device *dev;
 810
 811         if (WARN_ON(!ops))
 812                 return NULL;
 813
 814         if (WARN_ON(!ops->set_block))
 815                 return NULL;
 816
 817         if (WARN_ON(!name))
 818                 return NULL;
 819
 820         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 821                 return NULL;
 822
 823         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 824         if (!rfkill)
 825                 return NULL;
 826
 827         spin_lock_init(&rfkill->lock);
 828         INIT_LIST_HEAD(&rfkill->node);
 829         rfkill->type = type;
 830         rfkill->name = name;
 831         rfkill->ops = ops;
 832         rfkill->data = ops_data;
 833
 834         dev = &rfkill->dev;
 835         dev->class = &rfkill_class;
 836         dev->parent = parent;
 837         device_initialize(dev);
 838
 839         return rfkill;
 840 }
 841 EXPORT_SYMBOL(rfkill_alloc);
 842
 843 static void rfkill_poll(struct work_struct *work)
 844 {
 845         struct rfkill *rfkill;
 846
 847         rfkill = container_of(work, struct rfkill, poll_work.work);
 848
 849         /*
 850          * Poll hardware state -- driver will use one of the
 851          * rfkill_set{,_hw,_sw}_state functions and use its
 852          * return value to update the current status.
 853          */
 854         rfkill->ops->poll(rfkill, rfkill->data);
 855
 856         schedule_delayed_work(&rfkill->poll_work,
 857                 round_jiffies_relative(POLL_INTERVAL));
 858 }
 859
 860 static void rfkill_uevent_work(struct work_struct *work)
 861 {
 862         struct rfkill *rfkill;
 863
 864         rfkill = container_of(work, struct rfkill, uevent_work);
 865
 866         mutex_lock(&rfkill_global_mutex);
 867         rfkill_event(rfkill);
 868         mutex_unlock(&rfkill_global_mutex);
 869 }
 870
 871 static void rfkill_sync_work(struct work_struct *work)
 872 {
 873         struct rfkill *rfkill;
 874         bool cur;
 875
 876         rfkill = container_of(work, struct rfkill, sync_work);
 877
 878         mutex_lock(&rfkill_global_mutex);
 879         cur = rfkill_global_states[rfkill->type].cur;
 880         rfkill_set_block(rfkill, cur);
 881         mutex_unlock(&rfkill_global_mutex);
 882 }
 883
 884 int __must_check rfkill_register(struct rfkill *rfkill)
 885 {
 886         static unsigned long rfkill_no;
 887         struct device *dev = &rfkill->dev;
 888         int error;
 889
 890         BUG_ON(!rfkill);
 891
 892         mutex_lock(&rfkill_global_mutex);
 893
 894         if (rfkill->registered) {
 895                 error = -EALREADY;
 896                 goto unlock;
 897         }
 898
 899         rfkill->idx = rfkill_no;
 900         dev_set_name(dev, "rfkill%lu", rfkill_no);
 901         rfkill_no++;
 902
 903         list_add_tail(&rfkill->node, &rfkill_list);
 904
 905         error = device_add(dev);
 906         if (error)
 907                 goto remove;
 908
 909         error = rfkill_led_trigger_register(rfkill);
 910         if (error)
 911                 goto devdel;
 912
 913         rfkill->registered = true;
 914
 915         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 916         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 917         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 918
 919         if (rfkill->ops->poll)
 920                 schedule_delayed_work(&rfkill->poll_work,
 921                         round_jiffies_relative(POLL_INTERVAL));
 922
 923         if (!rfkill->persistent || rfkill_epo_lock_active) {
 924                 schedule_work(&rfkill->sync_work);
 925         } else {
 926 #ifdef CONFIG_RFKILL_INPUT
 927                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 928
 929                 if (!atomic_read(&rfkill_input_disabled))
 930                         __rfkill_switch_all(rfkill->type, soft_blocked);
 931 #endif
 932         }
 933
 934         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 935
 936         mutex_unlock(&rfkill_global_mutex);
 937         return 0;
 938
 939  devdel:
 940         device_del(&rfkill->dev);
 941  remove:
 942         list_del_init(&rfkill->node);
 943  unlock:
 944         mutex_unlock(&rfkill_global_mutex);
 945         return error;
 946 }
 947 EXPORT_SYMBOL(rfkill_register);
 948
 949 void rfkill_unregister(struct rfkill *rfkill)
 950 {
 951         BUG_ON(!rfkill);
 952
 953         if (rfkill->ops->poll)
 954                 cancel_delayed_work_sync(&rfkill->poll_work);
 955
 956         cancel_work_sync(&rfkill->uevent_work);
 957         cancel_work_sync(&rfkill->sync_work);
 958
 959         rfkill->registered = false;
 960
 961         device_del(&rfkill->dev);
 962
 963         mutex_lock(&rfkill_global_mutex);
 964         rfkill_send_events(rfkill, RFKILL_OP_DEL);
 965         list_del_init(&rfkill->node);
 966         mutex_unlock(&rfkill_global_mutex);
 967
 968         rfkill_led_trigger_unregister(rfkill);
 969 }
 970 EXPORT_SYMBOL(rfkill_unregister);
 971
 972 void rfkill_destroy(struct rfkill *rfkill)
 973 {
 974         if (rfkill)
 975                 put_device(&rfkill->dev);
 976 }
 977 EXPORT_SYMBOL(rfkill_destroy);
 978
 979 static int rfkill_fop_open(struct inode *inode, struct file *file)
 980 {
 981         struct rfkill_data *data;
 982         struct rfkill *rfkill;
 983         struct rfkill_int_event *ev, *tmp;
 984
 985         data = kzalloc(sizeof(*data), GFP_KERNEL);
 986         if (!data)
 987                 return -ENOMEM;
 988
 989         INIT_LIST_HEAD(&data->events);
 990         mutex_init(&data->mtx);
 991         init_waitqueue_head(&data->read_wait);
 992
 993         mutex_lock(&rfkill_global_mutex);
 994         mutex_lock(&data->mtx);
 995         /*
 996          * start getting events from elsewhere but hold mtx to get
 997          * startup events added first
 998          */
 999         list_add(&data->list, &rfkill_fds);
1000
1001         list_for_each_entry(rfkill, &rfkill_list, node) {
1002                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1003                 if (!ev)
1004                         goto free;
1005                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1006                 list_add_tail(&ev->list, &data->events);
1007         }
1008         mutex_unlock(&data->mtx);
1009         mutex_unlock(&rfkill_global_mutex);
1010
1011         file->private_data = data;
1012
1013         return nonseekable_open(inode, file);
1014
1015  free:
1016         mutex_unlock(&data->mtx);
1017         mutex_unlock(&rfkill_global_mutex);
1018         mutex_destroy(&data->mtx);
1019         list_for_each_entry_safe(ev, tmp, &data->events, list)
1020                 kfree(ev);
1021         kfree(data);
1022         return -ENOMEM;
1023 }
1024
1025 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1026 {
1027         struct rfkill_data *data = file->private_data;
1028         unsigned int res = POLLOUT | POLLWRNORM;
1029
1030         poll_wait(file, &data->read_wait, wait);
1031
1032         mutex_lock(&data->mtx);
1033         if (!list_empty(&data->events))
1034                 res = POLLIN | POLLRDNORM;
1035         mutex_unlock(&data->mtx);
1036
1037         return res;
1038 }
1039
1040 static bool rfkill_readable(struct rfkill_data *data)
1041 {
1042         bool r;
1043
1044         mutex_lock(&data->mtx);
1045         r = !list_empty(&data->events);
1046         mutex_unlock(&data->mtx);
1047
1048         return r;
1049 }
1050
1051 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1052                                size_t count, loff_t *pos)
1053 {
1054         struct rfkill_data *data = file->private_data;
1055         struct rfkill_int_event *ev;
1056         unsigned long sz;
1057         int ret;
1058
1059         mutex_lock(&data->mtx);
1060
1061         while (list_empty(&data->events)) {
1062                 if (file->f_flags & O_NONBLOCK) {
1063                         ret = -EAGAIN;
1064                         goto out;
1065                 }
1066                 mutex_unlock(&data->mtx);
1067                 ret = wait_event_interruptible(data->read_wait,
1068                                                rfkill_readable(data));
1069                 mutex_lock(&data->mtx);
1070
1071                 if (ret)
1072                         goto out;
1073         }
1074
1075         ev = list_first_entry(&data->events, struct rfkill_int_event,
1076                                 list);
1077
1078         sz = min_t(unsigned long, sizeof(ev->ev), count);
1079         ret = sz;
1080         if (copy_to_user(buf, &ev->ev, sz))
1081                 ret = -EFAULT;
1082
1083         list_del(&ev->list);
1084         kfree(ev);
1085  out:
1086         mutex_unlock(&data->mtx);
1087         return ret;
1088 }
1089
1090 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1091                                 size_t count, loff_t *pos)
1092 {
1093         struct rfkill *rfkill;
1094         struct rfkill_event ev;
1095
1096         /* we don't need the 'hard' variable but accept it */
1097         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1098                 return -EINVAL;
1099
1100         /*
1101          * Copy as much data as we can accept into our 'ev' buffer,
1102          * but tell userspace how much we've copied so it can determine
1103          * our API version even in a write() call, if it cares.
1104          */
1105         count = min(count, sizeof(ev));
1106         if (copy_from_user(&ev, buf, count))
1107                 return -EFAULT;
1108
1109         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1110                 return -EINVAL;
1111
1112         if (ev.type >= NUM_RFKILL_TYPES)
1113                 return -EINVAL;
1114
1115         mutex_lock(&rfkill_global_mutex);
1116
1117         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1118                 if (ev.type == RFKILL_TYPE_ALL) {
1119                         enum rfkill_type i;
1120                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1121                                 rfkill_global_states[i].cur = ev.soft;
1122                 } else {
1123                         rfkill_global_states[ev.type].cur = ev.soft;
1124                 }
1125         }
1126
1127         list_for_each_entry(rfkill, &rfkill_list, node) {
1128                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1129                         continue;
1130
1131                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1132                         continue;
1133
1134                 rfkill_set_block(rfkill, ev.soft);
1135         }
1136         mutex_unlock(&rfkill_global_mutex);
1137
1138         return count;
1139 }
1140
1141 static int rfkill_fop_release(struct inode *inode, struct file *file)
1142 {
1143         struct rfkill_data *data = file->private_data;
1144         struct rfkill_int_event *ev, *tmp;
1145
1146         mutex_lock(&rfkill_global_mutex);
1147         list_del(&data->list);
1148         mutex_unlock(&rfkill_global_mutex);
1149
1150         mutex_destroy(&data->mtx);
1151         list_for_each_entry_safe(ev, tmp, &data->events, list)
1152                 kfree(ev);
1153
1154 #ifdef CONFIG_RFKILL_INPUT
1155         if (data->input_handler)
1156                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1157                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1158 #endif
1159
1160         kfree(data);
1161
1162         return 0;
1163 }
1164
1165 #ifdef CONFIG_RFKILL_INPUT
1166 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1167                              unsigned long arg)
1168 {
1169         struct rfkill_data *data = file->private_data;
1170
1171         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1172                 return -ENOSYS;
1173
1174         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1175                 return -ENOSYS;
1176
1177         mutex_lock(&data->mtx);
1178
1179         if (!data->input_handler) {
1180                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1181                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1182                 data->input_handler = true;
1183         }
1184
1185         mutex_unlock(&data->mtx);
1186
1187         return 0;
1188 }
1189 #endif
1190
1191 static const struct file_operations rfkill_fops = {
1192         .open           = rfkill_fop_open,
1193         .read           = rfkill_fop_read,
1194         .write          = rfkill_fop_write,
1195         .poll           = rfkill_fop_poll,
1196         .release        = rfkill_fop_release,
1197 #ifdef CONFIG_RFKILL_INPUT
1198         .unlocked_ioctl = rfkill_fop_ioctl,
1199         .compat_ioctl   = rfkill_fop_ioctl,
1200 #endif
1201 };
1202
1203 static struct miscdevice rfkill_miscdev = {
1204         .name   = "rfkill",
1205         .fops   = &rfkill_fops,
1206         .minor  = MISC_DYNAMIC_MINOR,
1207 };
1208
1209 static int __init rfkill_init(void)
1210 {
1211         int error;
1212         int i;
1213
1214         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1215                 rfkill_global_states[i].cur = !rfkill_default_state;
1216
1217         error = class_register(&rfkill_class);
1218         if (error)
1219                 goto out;
1220
1221         error = misc_register(&rfkill_miscdev);
1222         if (error) {
1223                 class_unregister(&rfkill_class);
1224                 goto out;
1225         }
1226
1227 #ifdef CONFIG_RFKILL_INPUT
1228         error = rfkill_handler_init();
1229         if (error) {
1230                 misc_deregister(&rfkill_miscdev);
1231                 class_unregister(&rfkill_class);
1232                 goto out;
1233         }
1234 #endif
1235
1236  out:
1237         return error;
1238 }
1239 subsys_initcall(rfkill_init);
1240
1241 static void __exit rfkill_exit(void)
1242 {
1243 #ifdef CONFIG_RFKILL_INPUT
1244         rfkill_handler_exit();
1245 #endif
1246         misc_deregister(&rfkill_miscdev);
1247         class_unregister(&rfkill_class);
1248 }
1249 module_exit(rfkill_exit);