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/spinlock.h>
  31 #include <linux/miscdevice.h>
  32 #include <linux/wait.h>
  33 #include <linux/poll.h>
  34 #include <linux/fs.h>
  35
  36 #include "rfkill.h"
  37
  38 #define POLL_INTERVAL           (5 * HZ)
  39
  40 #define RFKILL_BLOCK_HW         BIT(0)
  41 #define RFKILL_BLOCK_SW         BIT(1)
  42 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  43 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  44                                  RFKILL_BLOCK_SW |\
  45                                  RFKILL_BLOCK_SW_PREV)
  46 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  47
  48 struct rfkill {
  49         spinlock_t              lock;
  50
  51         const char              *name;
  52         enum rfkill_type        type;
  53
  54         unsigned long           state;
  55
  56         u32                     idx;
  57
  58         bool                    registered;
  59         bool                    persistent;
  60
  61         const struct rfkill_ops *ops;
  62         void                    *data;
  63
  64 #ifdef CONFIG_RFKILL_LEDS
  65         struct led_trigger      led_trigger;
  66         const char              *ledtrigname;
  67 #endif
  68
  69         struct device           dev;
  70         struct list_head        node;
  71
  72         struct delayed_work     poll_work;
  73         struct work_struct      uevent_work;
  74         struct work_struct      sync_work;
  75 };
  76 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
  77
  78 struct rfkill_int_event {
  79         struct list_head        list;
  80         struct rfkill_event     ev;
  81 };
  82
  83 struct rfkill_data {
  84         struct list_head        list;
  85         struct list_head        events;
  86         struct mutex            mtx;
  87         wait_queue_head_t       read_wait;
  88         bool                    input_handler;
  89 };
  90
  91
  92 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  93 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  94 MODULE_DESCRIPTION("RF switch support");
  95 MODULE_LICENSE("GPL");
  96
  97
  98 /*
  99  * The locking here should be made much smarter, we currently have
 100  * a bit of a stupid situation because drivers might want to register
 101  * the rfkill struct under their own lock, and take this lock during
 102  * rfkill method calls -- which will cause an AB-BA deadlock situation.
 103  *
 104  * To fix that, we need to rework this code here to be mostly lock-free
 105  * and only use the mutex for list manipulations, not to protect the
 106  * various other global variables. Then we can avoid holding the mutex
 107  * around driver operations, and all is happy.
 108  */
 109 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 110 static DEFINE_MUTEX(rfkill_global_mutex);
 111 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 112
 113 static unsigned int rfkill_default_state = 1;
 114 module_param_named(default_state, rfkill_default_state, uint, 0444);
 115 MODULE_PARM_DESC(default_state,
 116                  "Default initial state for all radio types, 0 = radio off");
 117
 118 static struct {
 119         bool cur, sav;
 120 } rfkill_global_states[NUM_RFKILL_TYPES];
 121
 122 static bool rfkill_epo_lock_active;
 123
 124
 125 #ifdef CONFIG_RFKILL_LEDS
 126 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 127 {
 128         struct led_trigger *trigger;
 129
 130         if (!rfkill->registered)
 131                 return;
 132
 133         trigger = &rfkill->led_trigger;
 134
 135         if (rfkill->state & RFKILL_BLOCK_ANY)
 136                 led_trigger_event(trigger, LED_OFF);
 137         else
 138                 led_trigger_event(trigger, LED_FULL);
 139 }
 140
 141 static void rfkill_led_trigger_activate(struct led_classdev *led)
 142 {
 143         struct rfkill *rfkill;
 144
 145         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 146
 147         rfkill_led_trigger_event(rfkill);
 148 }
 149
 150 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 151 {
 152         return rfkill->led_trigger.name;
 153 }
 154 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 155
 156 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 157 {
 158         BUG_ON(!rfkill);
 159
 160         rfkill->ledtrigname = name;
 161 }
 162 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 163
 164 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 165 {
 166         rfkill->led_trigger.name = rfkill->ledtrigname
 167                                         ? : dev_name(&rfkill->dev);
 168         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 169         return led_trigger_register(&rfkill->led_trigger);
 170 }
 171
 172 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 173 {
 174         led_trigger_unregister(&rfkill->led_trigger);
 175 }
 176 #else
 177 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 178 {
 179 }
 180
 181 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 182 {
 183         return 0;
 184 }
 185
 186 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 187 {
 188 }
 189 #endif /* CONFIG_RFKILL_LEDS */
 190
 191 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 192                               enum rfkill_operation op)
 193 {
 194         unsigned long flags;
 195
 196         ev->idx = rfkill->idx;
 197         ev->type = rfkill->type;
 198         ev->op = op;
 199
 200         spin_lock_irqsave(&rfkill->lock, flags);
 201         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 202         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 203                                         RFKILL_BLOCK_SW_PREV));
 204         spin_unlock_irqrestore(&rfkill->lock, flags);
 205 }
 206
 207 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 208 {
 209         struct rfkill_data *data;
 210         struct rfkill_int_event *ev;
 211
 212         list_for_each_entry(data, &rfkill_fds, list) {
 213                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 214                 if (!ev)
 215                         continue;
 216                 rfkill_fill_event(&ev->ev, rfkill, op);
 217                 mutex_lock(&data->mtx);
 218                 list_add_tail(&ev->list, &data->events);
 219                 mutex_unlock(&data->mtx);
 220                 wake_up_interruptible(&data->read_wait);
 221         }
 222 }
 223
 224 static void rfkill_event(struct rfkill *rfkill)
 225 {
 226         if (!rfkill->registered)
 227                 return;
 228
 229         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 230
 231         /* also send event to /dev/rfkill */
 232         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 233 }
 234
 235 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
 236                                   bool blocked, bool *change)
 237 {
 238         unsigned long flags;
 239         bool prev, any;
 240
 241         BUG_ON(!rfkill);
 242
 243         spin_lock_irqsave(&rfkill->lock, flags);
 244         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 245         if (blocked)
 246                 rfkill->state |= RFKILL_BLOCK_HW;
 247         else
 248                 rfkill->state &= ~RFKILL_BLOCK_HW;
 249         *change = prev != blocked;
 250         any = rfkill->state & RFKILL_BLOCK_ANY;
 251         spin_unlock_irqrestore(&rfkill->lock, flags);
 252
 253         rfkill_led_trigger_event(rfkill);
 254
 255         return any;
 256 }
 257
 258 /**
 259  * rfkill_set_block - wrapper for set_block method
 260  *
 261  * @rfkill: the rfkill struct to use
 262  * @blocked: the new software state
 263  *
 264  * Calls the set_block method (when applicable) and handles notifications
 265  * etc. as well.
 266  */
 267 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 268 {
 269         unsigned long flags;
 270         int err;
 271
 272         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 273                 return;
 274
 275         /*
 276          * Some platforms (...!) generate input events which affect the
 277          * _hard_ kill state -- whenever something tries to change the
 278          * current software state query the hardware state too.
 279          */
 280         if (rfkill->ops->query)
 281                 rfkill->ops->query(rfkill, rfkill->data);
 282
 283         spin_lock_irqsave(&rfkill->lock, flags);
 284         if (rfkill->state & RFKILL_BLOCK_SW)
 285                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 286         else
 287                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 288
 289         if (blocked)
 290                 rfkill->state |= RFKILL_BLOCK_SW;
 291         else
 292                 rfkill->state &= ~RFKILL_BLOCK_SW;
 293
 294         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 295         spin_unlock_irqrestore(&rfkill->lock, flags);
 296
 297         err = rfkill->ops->set_block(rfkill->data, blocked);
 298
 299         spin_lock_irqsave(&rfkill->lock, flags);
 300         if (err) {
 301                 /*
 302                  * Failed -- reset status to _prev, this may be different
 303                  * from what set set _PREV to earlier in this function
 304                  * if rfkill_set_sw_state was invoked.
 305                  */
 306                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 307                         rfkill->state |= RFKILL_BLOCK_SW;
 308                 else
 309                         rfkill->state &= ~RFKILL_BLOCK_SW;
 310         }
 311         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 312         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 313         spin_unlock_irqrestore(&rfkill->lock, flags);
 314
 315         rfkill_led_trigger_event(rfkill);
 316         rfkill_event(rfkill);
 317 }
 318
 319 #ifdef CONFIG_RFKILL_INPUT
 320 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 321
 322 /**
 323  * __rfkill_switch_all - Toggle state of all switches of given type
 324  * @type: type of interfaces to be affected
 325  * @state: the new state
 326  *
 327  * This function sets the state of all switches of given type,
 328  * unless a specific switch is claimed by userspace (in which case,
 329  * that switch is left alone) or suspended.
 330  *
 331  * Caller must have acquired rfkill_global_mutex.
 332  */
 333 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 334 {
 335         struct rfkill *rfkill;
 336
 337         rfkill_global_states[type].cur = blocked;
 338         list_for_each_entry(rfkill, &rfkill_list, node) {
 339                 if (rfkill->type != type)
 340                         continue;
 341
 342                 rfkill_set_block(rfkill, blocked);
 343         }
 344 }
 345
 346 /**
 347  * rfkill_switch_all - Toggle state of all switches of given type
 348  * @type: type of interfaces to be affected
 349  * @state: the new state
 350  *
 351  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 352  * Please refer to __rfkill_switch_all() for details.
 353  *
 354  * Does nothing if the EPO lock is active.
 355  */
 356 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 357 {
 358         if (atomic_read(&rfkill_input_disabled))
 359                 return;
 360
 361         mutex_lock(&rfkill_global_mutex);
 362
 363         if (!rfkill_epo_lock_active)
 364                 __rfkill_switch_all(type, blocked);
 365
 366         mutex_unlock(&rfkill_global_mutex);
 367 }
 368
 369 /**
 370  * rfkill_epo - emergency power off all transmitters
 371  *
 372  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 373  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 374  *
 375  * The global state before the EPO is saved and can be restored later
 376  * using rfkill_restore_states().
 377  */
 378 void rfkill_epo(void)
 379 {
 380         struct rfkill *rfkill;
 381         int i;
 382
 383         if (atomic_read(&rfkill_input_disabled))
 384                 return;
 385
 386         mutex_lock(&rfkill_global_mutex);
 387
 388         rfkill_epo_lock_active = true;
 389         list_for_each_entry(rfkill, &rfkill_list, node)
 390                 rfkill_set_block(rfkill, true);
 391
 392         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 393                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 394                 rfkill_global_states[i].cur = true;
 395         }
 396
 397         mutex_unlock(&rfkill_global_mutex);
 398 }
 399
 400 /**
 401  * rfkill_restore_states - restore global states
 402  *
 403  * Restore (and sync switches to) the global state from the
 404  * states in rfkill_default_states.  This can undo the effects of
 405  * a call to rfkill_epo().
 406  */
 407 void rfkill_restore_states(void)
 408 {
 409         int i;
 410
 411         if (atomic_read(&rfkill_input_disabled))
 412                 return;
 413
 414         mutex_lock(&rfkill_global_mutex);
 415
 416         rfkill_epo_lock_active = false;
 417         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 418                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 419         mutex_unlock(&rfkill_global_mutex);
 420 }
 421
 422 /**
 423  * rfkill_remove_epo_lock - unlock state changes
 424  *
 425  * Used by rfkill-input manually unlock state changes, when
 426  * the EPO switch is deactivated.
 427  */
 428 void rfkill_remove_epo_lock(void)
 429 {
 430         if (atomic_read(&rfkill_input_disabled))
 431                 return;
 432
 433         mutex_lock(&rfkill_global_mutex);
 434         rfkill_epo_lock_active = false;
 435         mutex_unlock(&rfkill_global_mutex);
 436 }
 437
 438 /**
 439  * rfkill_is_epo_lock_active - returns true EPO is active
 440  *
 441  * Returns 0 (false) if there is NOT an active EPO contidion,
 442  * and 1 (true) if there is an active EPO contition, which
 443  * locks all radios in one of the BLOCKED states.
 444  *
 445  * Can be called in atomic context.
 446  */
 447 bool rfkill_is_epo_lock_active(void)
 448 {
 449         return rfkill_epo_lock_active;
 450 }
 451
 452 /**
 453  * rfkill_get_global_sw_state - returns global state for a type
 454  * @type: the type to get the global state of
 455  *
 456  * Returns the current global state for a given wireless
 457  * device type.
 458  */
 459 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 460 {
 461         return rfkill_global_states[type].cur;
 462 }
 463 #endif
 464
 465
 466 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 467 {
 468         bool ret, change;
 469
 470         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 471
 472         if (!rfkill->registered)
 473                 return ret;
 474
 475         if (change)
 476                 schedule_work(&rfkill->uevent_work);
 477
 478         return ret;
 479 }
 480 EXPORT_SYMBOL(rfkill_set_hw_state);
 481
 482 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 483 {
 484         u32 bit = RFKILL_BLOCK_SW;
 485
 486         /* if in a ops->set_block right now, use other bit */
 487         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 488                 bit = RFKILL_BLOCK_SW_PREV;
 489
 490         if (blocked)
 491                 rfkill->state |= bit;
 492         else
 493                 rfkill->state &= ~bit;
 494 }
 495
 496 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 497 {
 498         unsigned long flags;
 499         bool prev, hwblock;
 500
 501         BUG_ON(!rfkill);
 502
 503         spin_lock_irqsave(&rfkill->lock, flags);
 504         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 505         __rfkill_set_sw_state(rfkill, blocked);
 506         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 507         blocked = blocked || hwblock;
 508         spin_unlock_irqrestore(&rfkill->lock, flags);
 509
 510         if (!rfkill->registered)
 511                 return blocked;
 512
 513         if (prev != blocked && !hwblock)
 514                 schedule_work(&rfkill->uevent_work);
 515
 516         rfkill_led_trigger_event(rfkill);
 517
 518         return blocked;
 519 }
 520 EXPORT_SYMBOL(rfkill_set_sw_state);
 521
 522 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 523 {
 524         unsigned long flags;
 525
 526         BUG_ON(!rfkill);
 527         BUG_ON(rfkill->registered);
 528
 529         spin_lock_irqsave(&rfkill->lock, flags);
 530         __rfkill_set_sw_state(rfkill, blocked);
 531         rfkill->persistent = true;
 532         spin_unlock_irqrestore(&rfkill->lock, flags);
 533 }
 534 EXPORT_SYMBOL(rfkill_init_sw_state);
 535
 536 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 537 {
 538         unsigned long flags;
 539         bool swprev, hwprev;
 540
 541         BUG_ON(!rfkill);
 542
 543         spin_lock_irqsave(&rfkill->lock, flags);
 544
 545         /*
 546          * No need to care about prev/setblock ... this is for uevent only
 547          * and that will get triggered by rfkill_set_block anyway.
 548          */
 549         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 550         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 551         __rfkill_set_sw_state(rfkill, sw);
 552
 553         spin_unlock_irqrestore(&rfkill->lock, flags);
 554
 555         if (!rfkill->registered) {
 556                 rfkill->persistent = true;
 557         } else {
 558                 if (swprev != sw || hwprev != hw)
 559                         schedule_work(&rfkill->uevent_work);
 560
 561                 rfkill_led_trigger_event(rfkill);
 562         }
 563 }
 564 EXPORT_SYMBOL(rfkill_set_states);
 565
 566 static ssize_t rfkill_name_show(struct device *dev,
 567                                 struct device_attribute *attr,
 568                                 char *buf)
 569 {
 570         struct rfkill *rfkill = to_rfkill(dev);
 571
 572         return sprintf(buf, "%s\n", rfkill->name);
 573 }
 574
 575 static const char *rfkill_get_type_str(enum rfkill_type type)
 576 {
 577         switch (type) {
 578         case RFKILL_TYPE_WLAN:
 579                 return "wlan";
 580         case RFKILL_TYPE_BLUETOOTH:
 581                 return "bluetooth";
 582         case RFKILL_TYPE_UWB:
 583                 return "ultrawideband";
 584         case RFKILL_TYPE_WIMAX:
 585                 return "wimax";
 586         case RFKILL_TYPE_WWAN:
 587                 return "wwan";
 588         default:
 589                 BUG();
 590         }
 591
 592         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_WWAN + 1);
 593 }
 594
 595 static ssize_t rfkill_type_show(struct device *dev,
 596                                 struct device_attribute *attr,
 597                                 char *buf)
 598 {
 599         struct rfkill *rfkill = to_rfkill(dev);
 600
 601         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 602 }
 603
 604 static ssize_t rfkill_idx_show(struct device *dev,
 605                                struct device_attribute *attr,
 606                                char *buf)
 607 {
 608         struct rfkill *rfkill = to_rfkill(dev);
 609
 610         return sprintf(buf, "%d\n", rfkill->idx);
 611 }
 612
 613 static u8 user_state_from_blocked(unsigned long state)
 614 {
 615         if (state & RFKILL_BLOCK_HW)
 616                 return RFKILL_USER_STATE_HARD_BLOCKED;
 617         if (state & RFKILL_BLOCK_SW)
 618                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 619
 620         return RFKILL_USER_STATE_UNBLOCKED;
 621 }
 622
 623 static ssize_t rfkill_state_show(struct device *dev,
 624                                  struct device_attribute *attr,
 625                                  char *buf)
 626 {
 627         struct rfkill *rfkill = to_rfkill(dev);
 628         unsigned long flags;
 629         u32 state;
 630
 631         spin_lock_irqsave(&rfkill->lock, flags);
 632         state = rfkill->state;
 633         spin_unlock_irqrestore(&rfkill->lock, flags);
 634
 635         return sprintf(buf, "%d\n", user_state_from_blocked(state));
 636 }
 637
 638 static ssize_t rfkill_state_store(struct device *dev,
 639                                   struct device_attribute *attr,
 640                                   const char *buf, size_t count)
 641 {
 642         /*
 643          * The intention was that userspace can only take control over
 644          * a given device when/if rfkill-input doesn't control it due
 645          * to user_claim. Since user_claim is currently unsupported,
 646          * we never support changing the state from userspace -- this
 647          * can be implemented again later.
 648          */
 649
 650         return -EPERM;
 651 }
 652
 653 static ssize_t rfkill_claim_show(struct device *dev,
 654                                  struct device_attribute *attr,
 655                                  char *buf)
 656 {
 657         return sprintf(buf, "%d\n", 0);
 658 }
 659
 660 static ssize_t rfkill_claim_store(struct device *dev,
 661                                   struct device_attribute *attr,
 662                                   const char *buf, size_t count)
 663 {
 664         return -EOPNOTSUPP;
 665 }
 666
 667 static struct device_attribute rfkill_dev_attrs[] = {
 668         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 669         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 670         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
 671         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 672         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 673         __ATTR_NULL
 674 };
 675
 676 static void rfkill_release(struct device *dev)
 677 {
 678         struct rfkill *rfkill = to_rfkill(dev);
 679
 680         kfree(rfkill);
 681 }
 682
 683 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 684 {
 685         struct rfkill *rfkill = to_rfkill(dev);
 686         unsigned long flags;
 687         u32 state;
 688         int error;
 689
 690         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 691         if (error)
 692                 return error;
 693         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 694                                rfkill_get_type_str(rfkill->type));
 695         if (error)
 696                 return error;
 697         spin_lock_irqsave(&rfkill->lock, flags);
 698         state = rfkill->state;
 699         spin_unlock_irqrestore(&rfkill->lock, flags);
 700         error = add_uevent_var(env, "RFKILL_STATE=%d",
 701                                user_state_from_blocked(state));
 702         return error;
 703 }
 704
 705 void rfkill_pause_polling(struct rfkill *rfkill)
 706 {
 707         BUG_ON(!rfkill);
 708
 709         if (!rfkill->ops->poll)
 710                 return;
 711
 712         cancel_delayed_work_sync(&rfkill->poll_work);
 713 }
 714 EXPORT_SYMBOL(rfkill_pause_polling);
 715
 716 void rfkill_resume_polling(struct rfkill *rfkill)
 717 {
 718         BUG_ON(!rfkill);
 719
 720         if (!rfkill->ops->poll)
 721                 return;
 722
 723         schedule_work(&rfkill->poll_work.work);
 724 }
 725 EXPORT_SYMBOL(rfkill_resume_polling);
 726
 727 static int rfkill_suspend(struct device *dev, pm_message_t state)
 728 {
 729         struct rfkill *rfkill = to_rfkill(dev);
 730
 731         rfkill_pause_polling(rfkill);
 732
 733         return 0;
 734 }
 735
 736 static int rfkill_resume(struct device *dev)
 737 {
 738         struct rfkill *rfkill = to_rfkill(dev);
 739         bool cur;
 740
 741         if (!rfkill->persistent) {
 742                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 743                 rfkill_set_block(rfkill, cur);
 744         }
 745
 746         rfkill_resume_polling(rfkill);
 747
 748         return 0;
 749 }
 750
 751 static struct class rfkill_class = {
 752         .name           = "rfkill",
 753         .dev_release    = rfkill_release,
 754         .dev_attrs      = rfkill_dev_attrs,
 755         .dev_uevent     = rfkill_dev_uevent,
 756         .suspend        = rfkill_suspend,
 757         .resume         = rfkill_resume,
 758 };
 759
 760 bool rfkill_blocked(struct rfkill *rfkill)
 761 {
 762         unsigned long flags;
 763         u32 state;
 764
 765         spin_lock_irqsave(&rfkill->lock, flags);
 766         state = rfkill->state;
 767         spin_unlock_irqrestore(&rfkill->lock, flags);
 768
 769         return !!(state & RFKILL_BLOCK_ANY);
 770 }
 771 EXPORT_SYMBOL(rfkill_blocked);
 772
 773
 774 struct rfkill * __must_check rfkill_alloc(const char *name,
 775                                           struct device *parent,
 776                                           const enum rfkill_type type,
 777                                           const struct rfkill_ops *ops,
 778                                           void *ops_data)
 779 {
 780         struct rfkill *rfkill;
 781         struct device *dev;
 782
 783         if (WARN_ON(!ops))
 784                 return NULL;
 785
 786         if (WARN_ON(!ops->set_block))
 787                 return NULL;
 788
 789         if (WARN_ON(!name))
 790                 return NULL;
 791
 792         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 793                 return NULL;
 794
 795         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 796         if (!rfkill)
 797                 return NULL;
 798
 799         spin_lock_init(&rfkill->lock);
 800         INIT_LIST_HEAD(&rfkill->node);
 801         rfkill->type = type;
 802         rfkill->name = name;
 803         rfkill->ops = ops;
 804         rfkill->data = ops_data;
 805
 806         dev = &rfkill->dev;
 807         dev->class = &rfkill_class;
 808         dev->parent = parent;
 809         device_initialize(dev);
 810
 811         return rfkill;
 812 }
 813 EXPORT_SYMBOL(rfkill_alloc);
 814
 815 static void rfkill_poll(struct work_struct *work)
 816 {
 817         struct rfkill *rfkill;
 818
 819         rfkill = container_of(work, struct rfkill, poll_work.work);
 820
 821         /*
 822          * Poll hardware state -- driver will use one of the
 823          * rfkill_set{,_hw,_sw}_state functions and use its
 824          * return value to update the current status.
 825          */
 826         rfkill->ops->poll(rfkill, rfkill->data);
 827
 828         schedule_delayed_work(&rfkill->poll_work,
 829                 round_jiffies_relative(POLL_INTERVAL));
 830 }
 831
 832 static void rfkill_uevent_work(struct work_struct *work)
 833 {
 834         struct rfkill *rfkill;
 835
 836         rfkill = container_of(work, struct rfkill, uevent_work);
 837
 838         mutex_lock(&rfkill_global_mutex);
 839         rfkill_event(rfkill);
 840         mutex_unlock(&rfkill_global_mutex);
 841 }
 842
 843 static void rfkill_sync_work(struct work_struct *work)
 844 {
 845         struct rfkill *rfkill;
 846         bool cur;
 847
 848         rfkill = container_of(work, struct rfkill, sync_work);
 849
 850         mutex_lock(&rfkill_global_mutex);
 851         cur = rfkill_global_states[rfkill->type].cur;
 852         rfkill_set_block(rfkill, cur);
 853         mutex_unlock(&rfkill_global_mutex);
 854 }
 855
 856 int __must_check rfkill_register(struct rfkill *rfkill)
 857 {
 858         static unsigned long rfkill_no;
 859         struct device *dev = &rfkill->dev;
 860         int error;
 861
 862         BUG_ON(!rfkill);
 863
 864         mutex_lock(&rfkill_global_mutex);
 865
 866         if (rfkill->registered) {
 867                 error = -EALREADY;
 868                 goto unlock;
 869         }
 870
 871         rfkill->idx = rfkill_no;
 872         dev_set_name(dev, "rfkill%lu", rfkill_no);
 873         rfkill_no++;
 874
 875         list_add_tail(&rfkill->node, &rfkill_list);
 876
 877         error = device_add(dev);
 878         if (error)
 879                 goto remove;
 880
 881         error = rfkill_led_trigger_register(rfkill);
 882         if (error)
 883                 goto devdel;
 884
 885         rfkill->registered = true;
 886
 887         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 888         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 889         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 890
 891         if (rfkill->ops->poll)
 892                 schedule_delayed_work(&rfkill->poll_work,
 893                         round_jiffies_relative(POLL_INTERVAL));
 894
 895         if (!rfkill->persistent || rfkill_epo_lock_active) {
 896                 schedule_work(&rfkill->sync_work);
 897         } else {
 898 #ifdef CONFIG_RFKILL_INPUT
 899                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 900
 901                 if (!atomic_read(&rfkill_input_disabled))
 902                         __rfkill_switch_all(rfkill->type, soft_blocked);
 903 #endif
 904         }
 905
 906         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 907
 908         mutex_unlock(&rfkill_global_mutex);
 909         return 0;
 910
 911  devdel:
 912         device_del(&rfkill->dev);
 913  remove:
 914         list_del_init(&rfkill->node);
 915  unlock:
 916         mutex_unlock(&rfkill_global_mutex);
 917         return error;
 918 }
 919 EXPORT_SYMBOL(rfkill_register);
 920
 921 void rfkill_unregister(struct rfkill *rfkill)
 922 {
 923         BUG_ON(!rfkill);
 924
 925         if (rfkill->ops->poll)
 926                 cancel_delayed_work_sync(&rfkill->poll_work);
 927
 928         cancel_work_sync(&rfkill->uevent_work);
 929         cancel_work_sync(&rfkill->sync_work);
 930
 931         rfkill->registered = false;
 932
 933         device_del(&rfkill->dev);
 934
 935         mutex_lock(&rfkill_global_mutex);
 936         rfkill_send_events(rfkill, RFKILL_OP_DEL);
 937         list_del_init(&rfkill->node);
 938         mutex_unlock(&rfkill_global_mutex);
 939
 940         rfkill_led_trigger_unregister(rfkill);
 941 }
 942 EXPORT_SYMBOL(rfkill_unregister);
 943
 944 void rfkill_destroy(struct rfkill *rfkill)
 945 {
 946         if (rfkill)
 947                 put_device(&rfkill->dev);
 948 }
 949 EXPORT_SYMBOL(rfkill_destroy);
 950
 951 static int rfkill_fop_open(struct inode *inode, struct file *file)
 952 {
 953         struct rfkill_data *data;
 954         struct rfkill *rfkill;
 955         struct rfkill_int_event *ev, *tmp;
 956
 957         data = kzalloc(sizeof(*data), GFP_KERNEL);
 958         if (!data)
 959                 return -ENOMEM;
 960
 961         INIT_LIST_HEAD(&data->events);
 962         mutex_init(&data->mtx);
 963         init_waitqueue_head(&data->read_wait);
 964
 965         mutex_lock(&rfkill_global_mutex);
 966         mutex_lock(&data->mtx);
 967         /*
 968          * start getting events from elsewhere but hold mtx to get
 969          * startup events added first
 970          */
 971         list_add(&data->list, &rfkill_fds);
 972
 973         list_for_each_entry(rfkill, &rfkill_list, node) {
 974                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 975                 if (!ev)
 976                         goto free;
 977                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
 978                 list_add_tail(&ev->list, &data->events);
 979         }
 980         mutex_unlock(&data->mtx);
 981         mutex_unlock(&rfkill_global_mutex);
 982
 983         file->private_data = data;
 984
 985         return nonseekable_open(inode, file);
 986
 987  free:
 988         mutex_unlock(&data->mtx);
 989         mutex_unlock(&rfkill_global_mutex);
 990         mutex_destroy(&data->mtx);
 991         list_for_each_entry_safe(ev, tmp, &data->events, list)
 992                 kfree(ev);
 993         kfree(data);
 994         return -ENOMEM;
 995 }
 996
 997 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
 998 {
 999         struct rfkill_data *data = file->private_data;
1000         unsigned int res = POLLOUT | POLLWRNORM;
1001
1002         poll_wait(file, &data->read_wait, wait);
1003
1004         mutex_lock(&data->mtx);
1005         if (!list_empty(&data->events))
1006                 res = POLLIN | POLLRDNORM;
1007         mutex_unlock(&data->mtx);
1008
1009         return res;
1010 }
1011
1012 static bool rfkill_readable(struct rfkill_data *data)
1013 {
1014         bool r;
1015
1016         mutex_lock(&data->mtx);
1017         r = !list_empty(&data->events);
1018         mutex_unlock(&data->mtx);
1019
1020         return r;
1021 }
1022
1023 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1024                                size_t count, loff_t *pos)
1025 {
1026         struct rfkill_data *data = file->private_data;
1027         struct rfkill_int_event *ev;
1028         unsigned long sz;
1029         int ret;
1030
1031         mutex_lock(&data->mtx);
1032
1033         while (list_empty(&data->events)) {
1034                 if (file->f_flags & O_NONBLOCK) {
1035                         ret = -EAGAIN;
1036                         goto out;
1037                 }
1038                 mutex_unlock(&data->mtx);
1039                 ret = wait_event_interruptible(data->read_wait,
1040                                                rfkill_readable(data));
1041                 mutex_lock(&data->mtx);
1042
1043                 if (ret)
1044                         goto out;
1045         }
1046
1047         ev = list_first_entry(&data->events, struct rfkill_int_event,
1048                                 list);
1049
1050         sz = min_t(unsigned long, sizeof(ev->ev), count);
1051         ret = sz;
1052         if (copy_to_user(buf, &ev->ev, sz))
1053                 ret = -EFAULT;
1054
1055         list_del(&ev->list);
1056         kfree(ev);
1057  out:
1058         mutex_unlock(&data->mtx);
1059         return ret;
1060 }
1061
1062 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1063                                 size_t count, loff_t *pos)
1064 {
1065         struct rfkill *rfkill;
1066         struct rfkill_event ev;
1067
1068         /* we don't need the 'hard' variable but accept it */
1069         if (count < sizeof(ev) - 1)
1070                 return -EINVAL;
1071
1072         if (copy_from_user(&ev, buf, sizeof(ev) - 1))
1073                 return -EFAULT;
1074
1075         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1076                 return -EINVAL;
1077
1078         if (ev.type >= NUM_RFKILL_TYPES)
1079                 return -EINVAL;
1080
1081         mutex_lock(&rfkill_global_mutex);
1082
1083         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1084                 if (ev.type == RFKILL_TYPE_ALL) {
1085                         enum rfkill_type i;
1086                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1087                                 rfkill_global_states[i].cur = ev.soft;
1088                 } else {
1089                         rfkill_global_states[ev.type].cur = ev.soft;
1090                 }
1091         }
1092
1093         list_for_each_entry(rfkill, &rfkill_list, node) {
1094                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1095                         continue;
1096
1097                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1098                         continue;
1099
1100                 rfkill_set_block(rfkill, ev.soft);
1101         }
1102         mutex_unlock(&rfkill_global_mutex);
1103
1104         return count;
1105 }
1106
1107 static int rfkill_fop_release(struct inode *inode, struct file *file)
1108 {
1109         struct rfkill_data *data = file->private_data;
1110         struct rfkill_int_event *ev, *tmp;
1111
1112         mutex_lock(&rfkill_global_mutex);
1113         list_del(&data->list);
1114         mutex_unlock(&rfkill_global_mutex);
1115
1116         mutex_destroy(&data->mtx);
1117         list_for_each_entry_safe(ev, tmp, &data->events, list)
1118                 kfree(ev);
1119
1120 #ifdef CONFIG_RFKILL_INPUT
1121         if (data->input_handler)
1122                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1123                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1124 #endif
1125
1126         kfree(data);
1127
1128         return 0;
1129 }
1130
1131 #ifdef CONFIG_RFKILL_INPUT
1132 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1133                              unsigned long arg)
1134 {
1135         struct rfkill_data *data = file->private_data;
1136
1137         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1138                 return -ENOSYS;
1139
1140         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1141                 return -ENOSYS;
1142
1143         mutex_lock(&data->mtx);
1144
1145         if (!data->input_handler) {
1146                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1147                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1148                 data->input_handler = true;
1149         }
1150
1151         mutex_unlock(&data->mtx);
1152
1153         return 0;
1154 }
1155 #endif
1156
1157 static const struct file_operations rfkill_fops = {
1158         .open           = rfkill_fop_open,
1159         .read           = rfkill_fop_read,
1160         .write          = rfkill_fop_write,
1161         .poll           = rfkill_fop_poll,
1162         .release        = rfkill_fop_release,
1163 #ifdef CONFIG_RFKILL_INPUT
1164         .unlocked_ioctl = rfkill_fop_ioctl,
1165         .compat_ioctl   = rfkill_fop_ioctl,
1166 #endif
1167 };
1168
1169 static struct miscdevice rfkill_miscdev = {
1170         .name   = "rfkill",
1171         .fops   = &rfkill_fops,
1172         .minor  = MISC_DYNAMIC_MINOR,
1173 };
1174
1175 static int __init rfkill_init(void)
1176 {
1177         int error;
1178         int i;
1179
1180         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1181                 rfkill_global_states[i].cur = !rfkill_default_state;
1182
1183         error = class_register(&rfkill_class);
1184         if (error)
1185                 goto out;
1186
1187         error = misc_register(&rfkill_miscdev);
1188         if (error) {
1189                 class_unregister(&rfkill_class);
1190                 goto out;
1191         }
1192
1193 #ifdef CONFIG_RFKILL_INPUT
1194         error = rfkill_handler_init();
1195         if (error) {
1196                 misc_deregister(&rfkill_miscdev);
1197                 class_unregister(&rfkill_class);
1198                 goto out;
1199         }
1200 #endif
1201
1202  out:
1203         return error;
1204 }
1205 subsys_initcall(rfkill_init);
1206
1207 static void __exit rfkill_exit(void)
1208 {
1209 #ifdef CONFIG_RFKILL_INPUT
1210         rfkill_handler_exit();
1211 #endif
1212         misc_deregister(&rfkill_miscdev);
1213         class_unregister(&rfkill_class);
1214 }
1215 module_exit(rfkill_exit);