net/rfkill/core.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/capability.h>
  25 #include <linux/list.h>
  26 #include <linux/mutex.h>
  27 #include <linux/rfkill.h>
  28 #include <linux/sched.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/device.h>
  31 #include <linux/miscdevice.h>
  32 #include <linux/wait.h>
  33 #include <linux/poll.h>
  34 #include <linux/fs.h>
  35 #include <linux/slab.h>
  36
  37 #include "rfkill.h"
  38
  39 #define POLL_INTERVAL           (5 * HZ)
  40
  41 #define RFKILL_BLOCK_HW         BIT(0)
  42 #define RFKILL_BLOCK_SW         BIT(1)
  43 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  44 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  45                                  RFKILL_BLOCK_SW |\
  46                                  RFKILL_BLOCK_SW_PREV)
  47 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  48
  49 struct rfkill {
  50         spinlock_t              lock;
  51
  52         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 <IvDoorn@gmail.com>");
  96 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  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 #else
 180 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 181 {
 182 }
 183
 184 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 185 {
 186         return 0;
 187 }
 188
 189 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 190 {
 191 }
 192 #endif /* CONFIG_RFKILL_LEDS */
 193
 194 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 195                               enum rfkill_operation op)
 196 {
 197         unsigned long flags;
 198
 199         ev->idx = rfkill->idx;
 200         ev->type = rfkill->type;
 201         ev->op = op;
 202
 203         spin_lock_irqsave(&rfkill->lock, flags);
 204         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 205         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 206                                         RFKILL_BLOCK_SW_PREV));
 207         spin_unlock_irqrestore(&rfkill->lock, flags);
 208 }
 209
 210 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 211 {
 212         struct rfkill_data *data;
 213         struct rfkill_int_event *ev;
 214
 215         list_for_each_entry(data, &rfkill_fds, list) {
 216                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 217                 if (!ev)
 218                         continue;
 219                 rfkill_fill_event(&ev->ev, rfkill, op);
 220                 mutex_lock(&data->mtx);
 221                 list_add_tail(&ev->list, &data->events);
 222                 mutex_unlock(&data->mtx);
 223                 wake_up_interruptible(&data->read_wait);
 224         }
 225 }
 226
 227 static void rfkill_event(struct rfkill *rfkill)
 228 {
 229         if (!rfkill->registered)
 230                 return;
 231
 232         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 233
 234         /* also send event to /dev/rfkill */
 235         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 236 }
 237
 238 /**
 239  * rfkill_set_block - wrapper for set_block method
 240  *
 241  * @rfkill: the rfkill struct to use
 242  * @blocked: the new software state
 243  *
 244  * Calls the set_block method (when applicable) and handles notifications
 245  * etc. as well.
 246  */
 247 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 248 {
 249         unsigned long flags;
 250         bool prev, curr;
 251         int err;
 252
 253         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 254                 return;
 255
 256         /*
 257          * Some platforms (...!) generate input events which affect the
 258          * _hard_ kill state -- whenever something tries to change the
 259          * current software state query the hardware state too.
 260          */
 261         if (rfkill->ops->query)
 262                 rfkill->ops->query(rfkill, rfkill->data);
 263
 264         spin_lock_irqsave(&rfkill->lock, flags);
 265         prev = rfkill->state & RFKILL_BLOCK_SW;
 266
 267         if (prev)
 268                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 269         else
 270                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 271
 272         if (blocked)
 273                 rfkill->state |= RFKILL_BLOCK_SW;
 274         else
 275                 rfkill->state &= ~RFKILL_BLOCK_SW;
 276
 277         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 278         spin_unlock_irqrestore(&rfkill->lock, flags);
 279
 280         err = rfkill->ops->set_block(rfkill->data, blocked);
 281
 282         spin_lock_irqsave(&rfkill->lock, flags);
 283         if (err) {
 284                 /*
 285                  * Failed -- reset status to _PREV, which may be different
 286                  * from what we have set _PREV to earlier in this function
 287                  * if rfkill_set_sw_state was invoked.
 288                  */
 289                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 290                         rfkill->state |= RFKILL_BLOCK_SW;
 291                 else
 292                         rfkill->state &= ~RFKILL_BLOCK_SW;
 293         }
 294         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 295         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 296         curr = rfkill->state & RFKILL_BLOCK_SW;
 297         spin_unlock_irqrestore(&rfkill->lock, flags);
 298
 299         rfkill_led_trigger_event(rfkill);
 300
 301         if (prev != curr)
 302                 rfkill_event(rfkill);
 303 }
 304
 305 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
 306 {
 307         int i;
 308
 309         if (type != RFKILL_TYPE_ALL) {
 310                 rfkill_global_states[type].cur = blocked;
 311                 return;
 312         }
 313
 314         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 315                 rfkill_global_states[i].cur = blocked;
 316 }
 317
 318 #ifdef CONFIG_RFKILL_INPUT
 319 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 320
 321 /**
 322  * __rfkill_switch_all - Toggle state of all switches of given type
 323  * @type: type of interfaces to be affected
 324  * @blocked: the new state
 325  *
 326  * This function sets the state of all switches of given type,
 327  * unless a specific switch is suspended.
 328  *
 329  * Caller must have acquired rfkill_global_mutex.
 330  */
 331 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 332 {
 333         struct rfkill *rfkill;
 334
 335         rfkill_update_global_state(type, blocked);
 336         list_for_each_entry(rfkill, &rfkill_list, node) {
 337                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 338                         continue;
 339
 340                 rfkill_set_block(rfkill, blocked);
 341         }
 342 }
 343
 344 /**
 345  * rfkill_switch_all - Toggle state of all switches of given type
 346  * @type: type of interfaces to be affected
 347  * @blocked: the new state
 348  *
 349  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 350  * Please refer to __rfkill_switch_all() for details.
 351  *
 352  * Does nothing if the EPO lock is active.
 353  */
 354 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 355 {
 356         if (atomic_read(&rfkill_input_disabled))
 357                 return;
 358
 359         mutex_lock(&rfkill_global_mutex);
 360
 361         if (!rfkill_epo_lock_active)
 362                 __rfkill_switch_all(type, blocked);
 363
 364         mutex_unlock(&rfkill_global_mutex);
 365 }
 366
 367 /**
 368  * rfkill_epo - emergency power off all transmitters
 369  *
 370  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 371  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 372  *
 373  * The global state before the EPO is saved and can be restored later
 374  * using rfkill_restore_states().
 375  */
 376 void rfkill_epo(void)
 377 {
 378         struct rfkill *rfkill;
 379         int i;
 380
 381         if (atomic_read(&rfkill_input_disabled))
 382                 return;
 383
 384         mutex_lock(&rfkill_global_mutex);
 385
 386         rfkill_epo_lock_active = true;
 387         list_for_each_entry(rfkill, &rfkill_list, node)
 388                 rfkill_set_block(rfkill, true);
 389
 390         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 391                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 392                 rfkill_global_states[i].cur = true;
 393         }
 394
 395         mutex_unlock(&rfkill_global_mutex);
 396 }
 397
 398 /**
 399  * rfkill_restore_states - restore global states
 400  *
 401  * Restore (and sync switches to) the global state from the
 402  * states in rfkill_default_states.  This can undo the effects of
 403  * a call to rfkill_epo().
 404  */
 405 void rfkill_restore_states(void)
 406 {
 407         int i;
 408
 409         if (atomic_read(&rfkill_input_disabled))
 410                 return;
 411
 412         mutex_lock(&rfkill_global_mutex);
 413
 414         rfkill_epo_lock_active = false;
 415         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 416                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 417         mutex_unlock(&rfkill_global_mutex);
 418 }
 419
 420 /**
 421  * rfkill_remove_epo_lock - unlock state changes
 422  *
 423  * Used by rfkill-input manually unlock state changes, when
 424  * the EPO switch is deactivated.
 425  */
 426 void rfkill_remove_epo_lock(void)
 427 {
 428         if (atomic_read(&rfkill_input_disabled))
 429                 return;
 430
 431         mutex_lock(&rfkill_global_mutex);
 432         rfkill_epo_lock_active = false;
 433         mutex_unlock(&rfkill_global_mutex);
 434 }
 435
 436 /**
 437  * rfkill_is_epo_lock_active - returns true EPO is active
 438  *
 439  * Returns 0 (false) if there is NOT an active EPO contidion,
 440  * and 1 (true) if there is an active EPO contition, which
 441  * locks all radios in one of the BLOCKED states.
 442  *
 443  * Can be called in atomic context.
 444  */
 445 bool rfkill_is_epo_lock_active(void)
 446 {
 447         return rfkill_epo_lock_active;
 448 }
 449
 450 /**
 451  * rfkill_get_global_sw_state - returns global state for a type
 452  * @type: the type to get the global state of
 453  *
 454  * Returns the current global state for a given wireless
 455  * device type.
 456  */
 457 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 458 {
 459         return rfkill_global_states[type].cur;
 460 }
 461 #endif
 462
 463 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 464 {
 465         unsigned long flags;
 466         bool ret, prev;
 467
 468         BUG_ON(!rfkill);
 469
 470         spin_lock_irqsave(&rfkill->lock, flags);
 471         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 472         if (blocked)
 473                 rfkill->state |= RFKILL_BLOCK_HW;
 474         else
 475                 rfkill->state &= ~RFKILL_BLOCK_HW;
 476         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
 477         spin_unlock_irqrestore(&rfkill->lock, flags);
 478
 479         rfkill_led_trigger_event(rfkill);
 480
 481         if (!rfkill->registered)
 482                 return ret;
 483
 484         if (prev != blocked)
 485                 schedule_work(&rfkill->uevent_work);
 486
 487         return ret;
 488 }
 489 EXPORT_SYMBOL(rfkill_set_hw_state);
 490
 491 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 492 {
 493         u32 bit = RFKILL_BLOCK_SW;
 494
 495         /* if in a ops->set_block right now, use other bit */
 496         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 497                 bit = RFKILL_BLOCK_SW_PREV;
 498
 499         if (blocked)
 500                 rfkill->state |= bit;
 501         else
 502                 rfkill->state &= ~bit;
 503 }
 504
 505 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 506 {
 507         unsigned long flags;
 508         bool prev, hwblock;
 509
 510         BUG_ON(!rfkill);
 511
 512         spin_lock_irqsave(&rfkill->lock, flags);
 513         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 514         __rfkill_set_sw_state(rfkill, blocked);
 515         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 516         blocked = blocked || hwblock;
 517         spin_unlock_irqrestore(&rfkill->lock, flags);
 518
 519         if (!rfkill->registered)
 520                 return blocked;
 521
 522         if (prev != blocked && !hwblock)
 523                 schedule_work(&rfkill->uevent_work);
 524
 525         rfkill_led_trigger_event(rfkill);
 526
 527         return blocked;
 528 }
 529 EXPORT_SYMBOL(rfkill_set_sw_state);
 530
 531 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 532 {
 533         unsigned long flags;
 534
 535         BUG_ON(!rfkill);
 536         BUG_ON(rfkill->registered);
 537
 538         spin_lock_irqsave(&rfkill->lock, flags);
 539         __rfkill_set_sw_state(rfkill, blocked);
 540         rfkill->persistent = true;
 541         spin_unlock_irqrestore(&rfkill->lock, flags);
 542 }
 543 EXPORT_SYMBOL(rfkill_init_sw_state);
 544
 545 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 546 {
 547         unsigned long flags;
 548         bool swprev, hwprev;
 549
 550         BUG_ON(!rfkill);
 551
 552         spin_lock_irqsave(&rfkill->lock, flags);
 553
 554         /*
 555          * No need to care about prev/setblock ... this is for uevent only
 556          * and that will get triggered by rfkill_set_block anyway.
 557          */
 558         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 559         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 560         __rfkill_set_sw_state(rfkill, sw);
 561         if (hw)
 562                 rfkill->state |= RFKILL_BLOCK_HW;
 563         else
 564                 rfkill->state &= ~RFKILL_BLOCK_HW;
 565
 566         spin_unlock_irqrestore(&rfkill->lock, flags);
 567
 568         if (!rfkill->registered) {
 569                 rfkill->persistent = true;
 570         } else {
 571                 if (swprev != sw || hwprev != hw)
 572                         schedule_work(&rfkill->uevent_work);
 573
 574                 rfkill_led_trigger_event(rfkill);
 575         }
 576 }
 577 EXPORT_SYMBOL(rfkill_set_states);
 578
 579 static const char * const rfkill_types[] = {
 580         NULL, /* RFKILL_TYPE_ALL */
 581         "wlan",
 582         "bluetooth",
 583         "ultrawideband",
 584         "wimax",
 585         "wwan",
 586         "gps",
 587         "fm",
 588         "nfc",
 589 };
 590
 591 enum rfkill_type rfkill_find_type(const char *name)
 592 {
 593         int i;
 594
 595         BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
 596
 597         if (!name)
 598                 return RFKILL_TYPE_ALL;
 599
 600         for (i = 1; i < NUM_RFKILL_TYPES; i++)
 601                 if (!strcmp(name, rfkill_types[i]))
 602                         return i;
 603         return RFKILL_TYPE_ALL;
 604 }
 605 EXPORT_SYMBOL(rfkill_find_type);
 606
 607 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 608                          char *buf)
 609 {
 610         struct rfkill *rfkill = to_rfkill(dev);
 611
 612         return sprintf(buf, "%s\n", rfkill->name);
 613 }
 614 static DEVICE_ATTR_RO(name);
 615
 616 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 617                          char *buf)
 618 {
 619         struct rfkill *rfkill = to_rfkill(dev);
 620
 621         return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
 622 }
 623 static DEVICE_ATTR_RO(type);
 624
 625 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 626                           char *buf)
 627 {
 628         struct rfkill *rfkill = to_rfkill(dev);
 629
 630         return sprintf(buf, "%d\n", rfkill->idx);
 631 }
 632 static DEVICE_ATTR_RO(index);
 633
 634 static ssize_t persistent_show(struct device *dev,
 635                                struct device_attribute *attr, char *buf)
 636 {
 637         struct rfkill *rfkill = to_rfkill(dev);
 638
 639         return sprintf(buf, "%d\n", rfkill->persistent);
 640 }
 641 static DEVICE_ATTR_RO(persistent);
 642
 643 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 644                          char *buf)
 645 {
 646         struct rfkill *rfkill = to_rfkill(dev);
 647
 648         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 649 }
 650 static DEVICE_ATTR_RO(hard);
 651
 652 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 653                          char *buf)
 654 {
 655         struct rfkill *rfkill = to_rfkill(dev);
 656
 657         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 658 }
 659
 660 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 661                           const char *buf, size_t count)
 662 {
 663         struct rfkill *rfkill = to_rfkill(dev);
 664         unsigned long state;
 665         int err;
 666
 667         if (!capable(CAP_NET_ADMIN))
 668                 return -EPERM;
 669
 670         err = kstrtoul(buf, 0, &state);
 671         if (err)
 672                 return err;
 673
 674         if (state > 1 )
 675                 return -EINVAL;
 676
 677         mutex_lock(&rfkill_global_mutex);
 678         rfkill_set_block(rfkill, state);
 679         mutex_unlock(&rfkill_global_mutex);
 680
 681         return count;
 682 }
 683 static DEVICE_ATTR_RW(soft);
 684
 685 static u8 user_state_from_blocked(unsigned long state)
 686 {
 687         if (state & RFKILL_BLOCK_HW)
 688                 return RFKILL_USER_STATE_HARD_BLOCKED;
 689         if (state & RFKILL_BLOCK_SW)
 690                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 691
 692         return RFKILL_USER_STATE_UNBLOCKED;
 693 }
 694
 695 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 696                           char *buf)
 697 {
 698         struct rfkill *rfkill = to_rfkill(dev);
 699
 700         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 701 }
 702
 703 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 704                            const char *buf, size_t count)
 705 {
 706         struct rfkill *rfkill = to_rfkill(dev);
 707         unsigned long state;
 708         int err;
 709
 710         if (!capable(CAP_NET_ADMIN))
 711                 return -EPERM;
 712
 713         err = kstrtoul(buf, 0, &state);
 714         if (err)
 715                 return err;
 716
 717         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 718             state != RFKILL_USER_STATE_UNBLOCKED)
 719                 return -EINVAL;
 720
 721         mutex_lock(&rfkill_global_mutex);
 722         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 723         mutex_unlock(&rfkill_global_mutex);
 724
 725         return count;
 726 }
 727 static DEVICE_ATTR_RW(state);
 728
 729 static struct attribute *rfkill_dev_attrs[] = {
 730         &dev_attr_name.attr,
 731         &dev_attr_type.attr,
 732         &dev_attr_index.attr,
 733         &dev_attr_persistent.attr,
 734         &dev_attr_state.attr,
 735         &dev_attr_soft.attr,
 736         &dev_attr_hard.attr,
 737         NULL,
 738 };
 739 ATTRIBUTE_GROUPS(rfkill_dev);
 740
 741 static void rfkill_release(struct device *dev)
 742 {
 743         struct rfkill *rfkill = to_rfkill(dev);
 744
 745         kfree(rfkill);
 746 }
 747
 748 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 749 {
 750         struct rfkill *rfkill = to_rfkill(dev);
 751         unsigned long flags;
 752         u32 state;
 753         int error;
 754
 755         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 756         if (error)
 757                 return error;
 758         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 759                                rfkill_types[rfkill->type]);
 760         if (error)
 761                 return error;
 762         spin_lock_irqsave(&rfkill->lock, flags);
 763         state = rfkill->state;
 764         spin_unlock_irqrestore(&rfkill->lock, flags);
 765         error = add_uevent_var(env, "RFKILL_STATE=%d",
 766                                user_state_from_blocked(state));
 767         return error;
 768 }
 769
 770 void rfkill_pause_polling(struct rfkill *rfkill)
 771 {
 772         BUG_ON(!rfkill);
 773
 774         if (!rfkill->ops->poll)
 775                 return;
 776
 777         rfkill->polling_paused = true;
 778         cancel_delayed_work_sync(&rfkill->poll_work);
 779 }
 780 EXPORT_SYMBOL(rfkill_pause_polling);
 781
 782 void rfkill_resume_polling(struct rfkill *rfkill)
 783 {
 784         BUG_ON(!rfkill);
 785
 786         if (!rfkill->ops->poll)
 787                 return;
 788
 789         rfkill->polling_paused = false;
 790
 791         if (rfkill->suspended)
 792                 return;
 793
 794         queue_delayed_work(system_power_efficient_wq,
 795                            &rfkill->poll_work, 0);
 796 }
 797 EXPORT_SYMBOL(rfkill_resume_polling);
 798
 799 static __maybe_unused int rfkill_suspend(struct device *dev)
 800 {
 801         struct rfkill *rfkill = to_rfkill(dev);
 802
 803         rfkill->suspended = true;
 804         cancel_delayed_work_sync(&rfkill->poll_work);
 805
 806         return 0;
 807 }
 808
 809 static __maybe_unused int rfkill_resume(struct device *dev)
 810 {
 811         struct rfkill *rfkill = to_rfkill(dev);
 812         bool cur;
 813
 814         rfkill->suspended = false;
 815
 816         if (!rfkill->persistent) {
 817                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 818                 rfkill_set_block(rfkill, cur);
 819         }
 820
 821         if (rfkill->ops->poll && !rfkill->polling_paused)
 822                 queue_delayed_work(system_power_efficient_wq,
 823                                    &rfkill->poll_work, 0);
 824
 825         return 0;
 826 }
 827
 828 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 829
 830 static struct class rfkill_class = {
 831         .name           = "rfkill",
 832         .dev_release    = rfkill_release,
 833         .dev_groups     = rfkill_dev_groups,
 834         .dev_uevent     = rfkill_dev_uevent,
 835         .pm             = IS_ENABLED(CONFIG_RFKILL_PM) ? &rfkill_pm_ops : NULL,
 836 };
 837
 838 bool rfkill_blocked(struct rfkill *rfkill)
 839 {
 840         unsigned long flags;
 841         u32 state;
 842
 843         spin_lock_irqsave(&rfkill->lock, flags);
 844         state = rfkill->state;
 845         spin_unlock_irqrestore(&rfkill->lock, flags);
 846
 847         return !!(state & RFKILL_BLOCK_ANY);
 848 }
 849 EXPORT_SYMBOL(rfkill_blocked);
 850
 851
 852 struct rfkill * __must_check rfkill_alloc(const char *name,
 853                                           struct device *parent,
 854                                           const enum rfkill_type type,
 855                                           const struct rfkill_ops *ops,
 856                                           void *ops_data)
 857 {
 858         struct rfkill *rfkill;
 859         struct device *dev;
 860
 861         if (WARN_ON(!ops))
 862                 return NULL;
 863
 864         if (WARN_ON(!ops->set_block))
 865                 return NULL;
 866
 867         if (WARN_ON(!name))
 868                 return NULL;
 869
 870         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 871                 return NULL;
 872
 873         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 874         if (!rfkill)
 875                 return NULL;
 876
 877         spin_lock_init(&rfkill->lock);
 878         INIT_LIST_HEAD(&rfkill->node);
 879         rfkill->type = type;
 880         strcpy(rfkill->name, name);
 881         rfkill->ops = ops;
 882         rfkill->data = ops_data;
 883
 884         dev = &rfkill->dev;
 885         dev->class = &rfkill_class;
 886         dev->parent = parent;
 887         device_initialize(dev);
 888
 889         return rfkill;
 890 }
 891 EXPORT_SYMBOL(rfkill_alloc);
 892
 893 static void rfkill_poll(struct work_struct *work)
 894 {
 895         struct rfkill *rfkill;
 896
 897         rfkill = container_of(work, struct rfkill, poll_work.work);
 898
 899         /*
 900          * Poll hardware state -- driver will use one of the
 901          * rfkill_set{,_hw,_sw}_state functions and use its
 902          * return value to update the current status.
 903          */
 904         rfkill->ops->poll(rfkill, rfkill->data);
 905
 906         queue_delayed_work(system_power_efficient_wq,
 907                 &rfkill->poll_work,
 908                 round_jiffies_relative(POLL_INTERVAL));
 909 }
 910
 911 static void rfkill_uevent_work(struct work_struct *work)
 912 {
 913         struct rfkill *rfkill;
 914
 915         rfkill = container_of(work, struct rfkill, uevent_work);
 916
 917         mutex_lock(&rfkill_global_mutex);
 918         rfkill_event(rfkill);
 919         mutex_unlock(&rfkill_global_mutex);
 920 }
 921
 922 static void rfkill_sync_work(struct work_struct *work)
 923 {
 924         struct rfkill *rfkill;
 925         bool cur;
 926
 927         rfkill = container_of(work, struct rfkill, sync_work);
 928
 929         mutex_lock(&rfkill_global_mutex);
 930         cur = rfkill_global_states[rfkill->type].cur;
 931         rfkill_set_block(rfkill, cur);
 932         mutex_unlock(&rfkill_global_mutex);
 933 }
 934
 935 int __must_check rfkill_register(struct rfkill *rfkill)
 936 {
 937         static unsigned long rfkill_no;
 938         struct device *dev;
 939         int error;
 940
 941         if (!rfkill)
 942                 return -EINVAL;
 943
 944         dev = &rfkill->dev;
 945
 946         mutex_lock(&rfkill_global_mutex);
 947
 948         if (rfkill->registered) {
 949                 error = -EALREADY;
 950                 goto unlock;
 951         }
 952
 953         rfkill->idx = rfkill_no;
 954         dev_set_name(dev, "rfkill%lu", rfkill_no);
 955         rfkill_no++;
 956
 957         list_add_tail(&rfkill->node, &rfkill_list);
 958
 959         error = device_add(dev);
 960         if (error)
 961                 goto remove;
 962
 963         error = rfkill_led_trigger_register(rfkill);
 964         if (error)
 965                 goto devdel;
 966
 967         rfkill->registered = true;
 968
 969         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 970         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 971         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 972
 973         if (rfkill->ops->poll)
 974                 queue_delayed_work(system_power_efficient_wq,
 975                         &rfkill->poll_work,
 976                         round_jiffies_relative(POLL_INTERVAL));
 977
 978         if (!rfkill->persistent || rfkill_epo_lock_active) {
 979                 schedule_work(&rfkill->sync_work);
 980         } else {
 981 #ifdef CONFIG_RFKILL_INPUT
 982                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 983
 984                 if (!atomic_read(&rfkill_input_disabled))
 985                         __rfkill_switch_all(rfkill->type, soft_blocked);
 986 #endif
 987         }
 988
 989         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 990
 991         mutex_unlock(&rfkill_global_mutex);
 992         return 0;
 993
 994  devdel:
 995         device_del(&rfkill->dev);
 996  remove:
 997         list_del_init(&rfkill->node);
 998  unlock:
 999         mutex_unlock(&rfkill_global_mutex);
1000         return error;
1001 }
1002 EXPORT_SYMBOL(rfkill_register);
1003
1004 void rfkill_unregister(struct rfkill *rfkill)
1005 {
1006         BUG_ON(!rfkill);
1007
1008         if (rfkill->ops->poll)
1009                 cancel_delayed_work_sync(&rfkill->poll_work);
1010
1011         cancel_work_sync(&rfkill->uevent_work);
1012         cancel_work_sync(&rfkill->sync_work);
1013
1014         rfkill->registered = false;
1015
1016         device_del(&rfkill->dev);
1017
1018         mutex_lock(&rfkill_global_mutex);
1019         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1020         list_del_init(&rfkill->node);
1021         mutex_unlock(&rfkill_global_mutex);
1022
1023         rfkill_led_trigger_unregister(rfkill);
1024 }
1025 EXPORT_SYMBOL(rfkill_unregister);
1026
1027 void rfkill_destroy(struct rfkill *rfkill)
1028 {
1029         if (rfkill)
1030                 put_device(&rfkill->dev);
1031 }
1032 EXPORT_SYMBOL(rfkill_destroy);
1033
1034 static int rfkill_fop_open(struct inode *inode, struct file *file)
1035 {
1036         struct rfkill_data *data;
1037         struct rfkill *rfkill;
1038         struct rfkill_int_event *ev, *tmp;
1039
1040         data = kzalloc(sizeof(*data), GFP_KERNEL);
1041         if (!data)
1042                 return -ENOMEM;
1043
1044         INIT_LIST_HEAD(&data->events);
1045         mutex_init(&data->mtx);
1046         init_waitqueue_head(&data->read_wait);
1047
1048         mutex_lock(&rfkill_global_mutex);
1049         mutex_lock(&data->mtx);
1050         /*
1051          * start getting events from elsewhere but hold mtx to get
1052          * startup events added first
1053          */
1054
1055         list_for_each_entry(rfkill, &rfkill_list, node) {
1056                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1057                 if (!ev)
1058                         goto free;
1059                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1060                 list_add_tail(&ev->list, &data->events);
1061         }
1062         list_add(&data->list, &rfkill_fds);
1063         mutex_unlock(&data->mtx);
1064         mutex_unlock(&rfkill_global_mutex);
1065
1066         file->private_data = data;
1067
1068         return nonseekable_open(inode, file);
1069
1070  free:
1071         mutex_unlock(&data->mtx);
1072         mutex_unlock(&rfkill_global_mutex);
1073         mutex_destroy(&data->mtx);
1074         list_for_each_entry_safe(ev, tmp, &data->events, list)
1075                 kfree(ev);
1076         kfree(data);
1077         return -ENOMEM;
1078 }
1079
1080 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1081 {
1082         struct rfkill_data *data = file->private_data;
1083         unsigned int res = POLLOUT | POLLWRNORM;
1084
1085         poll_wait(file, &data->read_wait, wait);
1086
1087         mutex_lock(&data->mtx);
1088         if (!list_empty(&data->events))
1089                 res = POLLIN | POLLRDNORM;
1090         mutex_unlock(&data->mtx);
1091
1092         return res;
1093 }
1094
1095 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1096                                size_t count, loff_t *pos)
1097 {
1098         struct rfkill_data *data = file->private_data;
1099         struct rfkill_int_event *ev;
1100         unsigned long sz;
1101         int ret;
1102
1103         mutex_lock(&data->mtx);
1104
1105         while (list_empty(&data->events)) {
1106                 if (file->f_flags & O_NONBLOCK) {
1107                         ret = -EAGAIN;
1108                         goto out;
1109                 }
1110                 mutex_unlock(&data->mtx);
1111                 /* since we re-check and it just compares pointers,
1112                  * using !list_empty() without locking isn't a problem
1113                  */
1114                 ret = wait_event_interruptible(data->read_wait,
1115                                                !list_empty(&data->events));
1116                 mutex_lock(&data->mtx);
1117
1118                 if (ret)
1119                         goto out;
1120         }
1121
1122         ev = list_first_entry(&data->events, struct rfkill_int_event,
1123                                 list);
1124
1125         sz = min_t(unsigned long, sizeof(ev->ev), count);
1126         ret = sz;
1127         if (copy_to_user(buf, &ev->ev, sz))
1128                 ret = -EFAULT;
1129
1130         list_del(&ev->list);
1131         kfree(ev);
1132  out:
1133         mutex_unlock(&data->mtx);
1134         return ret;
1135 }
1136
1137 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1138                                 size_t count, loff_t *pos)
1139 {
1140         struct rfkill *rfkill;
1141         struct rfkill_event ev;
1142         int ret;
1143
1144         /* we don't need the 'hard' variable but accept it */
1145         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1146                 return -EINVAL;
1147
1148         /*
1149          * Copy as much data as we can accept into our 'ev' buffer,
1150          * but tell userspace how much we've copied so it can determine
1151          * our API version even in a write() call, if it cares.
1152          */
1153         count = min(count, sizeof(ev));
1154         if (copy_from_user(&ev, buf, count))
1155                 return -EFAULT;
1156
1157         if (ev.type >= NUM_RFKILL_TYPES)
1158                 return -EINVAL;
1159
1160         mutex_lock(&rfkill_global_mutex);
1161
1162         switch (ev.op) {
1163         case RFKILL_OP_CHANGE_ALL:
1164                 rfkill_update_global_state(ev.type, ev.soft);
1165                 list_for_each_entry(rfkill, &rfkill_list, node)
1166                         if (rfkill->type == ev.type ||
1167                             ev.type == RFKILL_TYPE_ALL)
1168                                 rfkill_set_block(rfkill, ev.soft);
1169                 ret = 0;
1170                 break;
1171         case RFKILL_OP_CHANGE:
1172                 list_for_each_entry(rfkill, &rfkill_list, node)
1173                         if (rfkill->idx == ev.idx &&
1174                             (rfkill->type == ev.type ||
1175                              ev.type == RFKILL_TYPE_ALL))
1176                                 rfkill_set_block(rfkill, ev.soft);
1177                 ret = 0;
1178                 break;
1179         default:
1180                 ret = -EINVAL;
1181                 break;
1182         }
1183
1184         mutex_unlock(&rfkill_global_mutex);
1185
1186         return ret ?: count;
1187 }
1188
1189 static int rfkill_fop_release(struct inode *inode, struct file *file)
1190 {
1191         struct rfkill_data *data = file->private_data;
1192         struct rfkill_int_event *ev, *tmp;
1193
1194         mutex_lock(&rfkill_global_mutex);
1195         list_del(&data->list);
1196         mutex_unlock(&rfkill_global_mutex);
1197
1198         mutex_destroy(&data->mtx);
1199         list_for_each_entry_safe(ev, tmp, &data->events, list)
1200                 kfree(ev);
1201
1202 #ifdef CONFIG_RFKILL_INPUT
1203         if (data->input_handler)
1204                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1205                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1206 #endif
1207
1208         kfree(data);
1209
1210         return 0;
1211 }
1212
1213 #ifdef CONFIG_RFKILL_INPUT
1214 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1215                              unsigned long arg)
1216 {
1217         struct rfkill_data *data = file->private_data;
1218
1219         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1220                 return -ENOSYS;
1221
1222         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1223                 return -ENOSYS;
1224
1225         mutex_lock(&data->mtx);
1226
1227         if (!data->input_handler) {
1228                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1229                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1230                 data->input_handler = true;
1231         }
1232
1233         mutex_unlock(&data->mtx);
1234
1235         return 0;
1236 }
1237 #endif
1238
1239 static const struct file_operations rfkill_fops = {
1240         .owner          = THIS_MODULE,
1241         .open           = rfkill_fop_open,
1242         .read           = rfkill_fop_read,
1243         .write          = rfkill_fop_write,
1244         .poll           = rfkill_fop_poll,
1245         .release        = rfkill_fop_release,
1246 #ifdef CONFIG_RFKILL_INPUT
1247         .unlocked_ioctl = rfkill_fop_ioctl,
1248         .compat_ioctl   = rfkill_fop_ioctl,
1249 #endif
1250         .llseek         = no_llseek,
1251 };
1252
1253 static struct miscdevice rfkill_miscdev = {
1254         .name   = "rfkill",
1255         .fops   = &rfkill_fops,
1256         .minor  = MISC_DYNAMIC_MINOR,
1257 };
1258
1259 static int __init rfkill_init(void)
1260 {
1261         int error;
1262
1263         rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1264
1265         error = class_register(&rfkill_class);
1266         if (error)
1267                 goto out;
1268
1269         error = misc_register(&rfkill_miscdev);
1270         if (error) {
1271                 class_unregister(&rfkill_class);
1272                 goto out;
1273         }
1274
1275 #ifdef CONFIG_RFKILL_INPUT
1276         error = rfkill_handler_init();
1277         if (error) {
1278                 misc_deregister(&rfkill_miscdev);
1279                 class_unregister(&rfkill_class);
1280                 goto out;
1281         }
1282 #endif
1283
1284  out:
1285         return error;
1286 }
1287 subsys_initcall(rfkill_init);
1288
1289 static void __exit rfkill_exit(void)
1290 {
1291 #ifdef CONFIG_RFKILL_INPUT
1292         rfkill_handler_exit();
1293 #endif
1294         misc_deregister(&rfkill_miscdev);
1295         class_unregister(&rfkill_class);
1296 }
1297 module_exit(rfkill_exit);