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/device.h>
  33 #include <linux/miscdevice.h>
  34 #include <linux/wait.h>
  35 #include <linux/poll.h>
  36 #include <linux/fs.h>
  37 #include <linux/slab.h>
  38
  39 #include "rfkill.h"
  40
  41 #define POLL_INTERVAL           (5 * HZ)
  42
  43 #define RFKILL_BLOCK_HW         BIT(0)
  44 #define RFKILL_BLOCK_SW         BIT(1)
  45 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  46 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  47                                  RFKILL_BLOCK_SW |\
  48                                  RFKILL_BLOCK_SW_PREV)
  49 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  50
  51 struct rfkill {
  52         spinlock_t              lock;
  53
  54         const char              *name;
  55         enum rfkill_type        type;
  56
  57         unsigned long           state;
  58
  59         u32                     idx;
  60
  61         bool                    registered;
  62         bool                    persistent;
  63
  64         const struct rfkill_ops *ops;
  65         void                    *data;
  66
  67 #ifdef CONFIG_RFKILL_LEDS
  68         struct led_trigger      led_trigger;
  69         const char              *ledtrigname;
  70 #endif
  71
  72         struct device           dev;
  73         struct list_head        node;
  74
  75         struct delayed_work     poll_work;
  76         struct work_struct      uevent_work;
  77         struct work_struct      sync_work;
  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 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
 239                                   bool blocked, bool *change)
 240 {
 241         unsigned long flags;
 242         bool prev, any;
 243
 244         BUG_ON(!rfkill);
 245
 246         spin_lock_irqsave(&rfkill->lock, flags);
 247         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 248         if (blocked)
 249                 rfkill->state |= RFKILL_BLOCK_HW;
 250         else
 251                 rfkill->state &= ~RFKILL_BLOCK_HW;
 252         *change = prev != blocked;
 253         any = !!(rfkill->state & RFKILL_BLOCK_ANY);
 254         spin_unlock_irqrestore(&rfkill->lock, flags);
 255
 256         rfkill_led_trigger_event(rfkill);
 257
 258         return any;
 259 }
 260
 261 /**
 262  * rfkill_set_block - wrapper for set_block method
 263  *
 264  * @rfkill: the rfkill struct to use
 265  * @blocked: the new software state
 266  *
 267  * Calls the set_block method (when applicable) and handles notifications
 268  * etc. as well.
 269  */
 270 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 271 {
 272         unsigned long flags;
 273         bool prev, curr;
 274         int err;
 275
 276         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 277                 return;
 278
 279         /*
 280          * Some platforms (...!) generate input events which affect the
 281          * _hard_ kill state -- whenever something tries to change the
 282          * current software state query the hardware state too.
 283          */
 284         if (rfkill->ops->query)
 285                 rfkill->ops->query(rfkill, rfkill->data);
 286
 287         spin_lock_irqsave(&rfkill->lock, flags);
 288         prev = rfkill->state & RFKILL_BLOCK_SW;
 289
 290         if (rfkill->state & RFKILL_BLOCK_SW)
 291                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 292         else
 293                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 294
 295         if (blocked)
 296                 rfkill->state |= RFKILL_BLOCK_SW;
 297         else
 298                 rfkill->state &= ~RFKILL_BLOCK_SW;
 299
 300         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 301         spin_unlock_irqrestore(&rfkill->lock, flags);
 302
 303         err = rfkill->ops->set_block(rfkill->data, blocked);
 304
 305         spin_lock_irqsave(&rfkill->lock, flags);
 306         if (err) {
 307                 /*
 308                  * Failed -- reset status to _prev, this may be different
 309                  * from what set set _PREV to earlier in this function
 310                  * if rfkill_set_sw_state was invoked.
 311                  */
 312                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 313                         rfkill->state |= RFKILL_BLOCK_SW;
 314                 else
 315                         rfkill->state &= ~RFKILL_BLOCK_SW;
 316         }
 317         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 318         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 319         curr = rfkill->state & RFKILL_BLOCK_SW;
 320         spin_unlock_irqrestore(&rfkill->lock, flags);
 321
 322         rfkill_led_trigger_event(rfkill);
 323
 324         if (prev != curr)
 325                 rfkill_event(rfkill);
 326 }
 327
 328 #ifdef CONFIG_RFKILL_INPUT
 329 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 330
 331 /**
 332  * __rfkill_switch_all - Toggle state of all switches of given type
 333  * @type: type of interfaces to be affected
 334  * @state: the new state
 335  *
 336  * This function sets the state of all switches of given type,
 337  * unless a specific switch is claimed by userspace (in which case,
 338  * that switch is left alone) or suspended.
 339  *
 340  * Caller must have acquired rfkill_global_mutex.
 341  */
 342 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 343 {
 344         struct rfkill *rfkill;
 345
 346         rfkill_global_states[type].cur = blocked;
 347         list_for_each_entry(rfkill, &rfkill_list, node) {
 348                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 349                         continue;
 350
 351                 rfkill_set_block(rfkill, blocked);
 352         }
 353 }
 354
 355 /**
 356  * rfkill_switch_all - Toggle state of all switches of given type
 357  * @type: type of interfaces to be affected
 358  * @state: the new state
 359  *
 360  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 361  * Please refer to __rfkill_switch_all() for details.
 362  *
 363  * Does nothing if the EPO lock is active.
 364  */
 365 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 366 {
 367         if (atomic_read(&rfkill_input_disabled))
 368                 return;
 369
 370         mutex_lock(&rfkill_global_mutex);
 371
 372         if (!rfkill_epo_lock_active)
 373                 __rfkill_switch_all(type, blocked);
 374
 375         mutex_unlock(&rfkill_global_mutex);
 376 }
 377
 378 /**
 379  * rfkill_epo - emergency power off all transmitters
 380  *
 381  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 382  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 383  *
 384  * The global state before the EPO is saved and can be restored later
 385  * using rfkill_restore_states().
 386  */
 387 void rfkill_epo(void)
 388 {
 389         struct rfkill *rfkill;
 390         int i;
 391
 392         if (atomic_read(&rfkill_input_disabled))
 393                 return;
 394
 395         mutex_lock(&rfkill_global_mutex);
 396
 397         rfkill_epo_lock_active = true;
 398         list_for_each_entry(rfkill, &rfkill_list, node)
 399                 rfkill_set_block(rfkill, true);
 400
 401         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 402                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 403                 rfkill_global_states[i].cur = true;
 404         }
 405
 406         mutex_unlock(&rfkill_global_mutex);
 407 }
 408
 409 /**
 410  * rfkill_restore_states - restore global states
 411  *
 412  * Restore (and sync switches to) the global state from the
 413  * states in rfkill_default_states.  This can undo the effects of
 414  * a call to rfkill_epo().
 415  */
 416 void rfkill_restore_states(void)
 417 {
 418         int i;
 419
 420         if (atomic_read(&rfkill_input_disabled))
 421                 return;
 422
 423         mutex_lock(&rfkill_global_mutex);
 424
 425         rfkill_epo_lock_active = false;
 426         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 427                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 428         mutex_unlock(&rfkill_global_mutex);
 429 }
 430
 431 /**
 432  * rfkill_remove_epo_lock - unlock state changes
 433  *
 434  * Used by rfkill-input manually unlock state changes, when
 435  * the EPO switch is deactivated.
 436  */
 437 void rfkill_remove_epo_lock(void)
 438 {
 439         if (atomic_read(&rfkill_input_disabled))
 440                 return;
 441
 442         mutex_lock(&rfkill_global_mutex);
 443         rfkill_epo_lock_active = false;
 444         mutex_unlock(&rfkill_global_mutex);
 445 }
 446
 447 /**
 448  * rfkill_is_epo_lock_active - returns true EPO is active
 449  *
 450  * Returns 0 (false) if there is NOT an active EPO contidion,
 451  * and 1 (true) if there is an active EPO contition, which
 452  * locks all radios in one of the BLOCKED states.
 453  *
 454  * Can be called in atomic context.
 455  */
 456 bool rfkill_is_epo_lock_active(void)
 457 {
 458         return rfkill_epo_lock_active;
 459 }
 460
 461 /**
 462  * rfkill_get_global_sw_state - returns global state for a type
 463  * @type: the type to get the global state of
 464  *
 465  * Returns the current global state for a given wireless
 466  * device type.
 467  */
 468 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 469 {
 470         return rfkill_global_states[type].cur;
 471 }
 472 #endif
 473
 474
 475 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 476 {
 477         bool ret, change;
 478
 479         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
 480
 481         if (!rfkill->registered)
 482                 return ret;
 483
 484         if (change)
 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 ssize_t name_show(struct device *dev, struct device_attribute *attr,
 580                          char *buf)
 581 {
 582         struct rfkill *rfkill = to_rfkill(dev);
 583
 584         return sprintf(buf, "%s\n", rfkill->name);
 585 }
 586 static DEVICE_ATTR_RO(name);
 587
 588 static const char *rfkill_get_type_str(enum rfkill_type type)
 589 {
 590         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_NFC + 1);
 591
 592         switch (type) {
 593         case RFKILL_TYPE_WLAN:
 594                 return "wlan";
 595         case RFKILL_TYPE_BLUETOOTH:
 596                 return "bluetooth";
 597         case RFKILL_TYPE_UWB:
 598                 return "ultrawideband";
 599         case RFKILL_TYPE_WIMAX:
 600                 return "wimax";
 601         case RFKILL_TYPE_WWAN:
 602                 return "wwan";
 603         case RFKILL_TYPE_GPS:
 604                 return "gps";
 605         case RFKILL_TYPE_FM:
 606                 return "fm";
 607         case RFKILL_TYPE_NFC:
 608                 return "nfc";
 609         default:
 610                 BUG();
 611         }
 612 }
 613
 614 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 615                          char *buf)
 616 {
 617         struct rfkill *rfkill = to_rfkill(dev);
 618
 619         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 620 }
 621 static DEVICE_ATTR_RO(type);
 622
 623 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 624                           char *buf)
 625 {
 626         struct rfkill *rfkill = to_rfkill(dev);
 627
 628         return sprintf(buf, "%d\n", rfkill->idx);
 629 }
 630 static DEVICE_ATTR_RO(index);
 631
 632 static ssize_t persistent_show(struct device *dev,
 633                                struct device_attribute *attr, char *buf)
 634 {
 635         struct rfkill *rfkill = to_rfkill(dev);
 636
 637         return sprintf(buf, "%d\n", rfkill->persistent);
 638 }
 639 static DEVICE_ATTR_RO(persistent);
 640
 641 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 642                          char *buf)
 643 {
 644         struct rfkill *rfkill = to_rfkill(dev);
 645
 646         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 647 }
 648 static DEVICE_ATTR_RO(hard);
 649
 650 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 651                          char *buf)
 652 {
 653         struct rfkill *rfkill = to_rfkill(dev);
 654
 655         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 656 }
 657
 658 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 659                           const char *buf, size_t count)
 660 {
 661         struct rfkill *rfkill = to_rfkill(dev);
 662         unsigned long state;
 663         int err;
 664
 665         if (!capable(CAP_NET_ADMIN))
 666                 return -EPERM;
 667
 668         err = kstrtoul(buf, 0, &state);
 669         if (err)
 670                 return err;
 671
 672         if (state > 1 )
 673                 return -EINVAL;
 674
 675         mutex_lock(&rfkill_global_mutex);
 676         rfkill_set_block(rfkill, state);
 677         mutex_unlock(&rfkill_global_mutex);
 678
 679         return count;
 680 }
 681 static DEVICE_ATTR_RW(soft);
 682
 683 static u8 user_state_from_blocked(unsigned long state)
 684 {
 685         if (state & RFKILL_BLOCK_HW)
 686                 return RFKILL_USER_STATE_HARD_BLOCKED;
 687         if (state & RFKILL_BLOCK_SW)
 688                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 689
 690         return RFKILL_USER_STATE_UNBLOCKED;
 691 }
 692
 693 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 694                           char *buf)
 695 {
 696         struct rfkill *rfkill = to_rfkill(dev);
 697
 698         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 699 }
 700
 701 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 702                            const char *buf, size_t count)
 703 {
 704         struct rfkill *rfkill = to_rfkill(dev);
 705         unsigned long state;
 706         int err;
 707
 708         if (!capable(CAP_NET_ADMIN))
 709                 return -EPERM;
 710
 711         err = kstrtoul(buf, 0, &state);
 712         if (err)
 713                 return err;
 714
 715         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 716             state != RFKILL_USER_STATE_UNBLOCKED)
 717                 return -EINVAL;
 718
 719         mutex_lock(&rfkill_global_mutex);
 720         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 721         mutex_unlock(&rfkill_global_mutex);
 722
 723         return count;
 724 }
 725 static DEVICE_ATTR_RW(state);
 726
 727 static ssize_t claim_show(struct device *dev, struct device_attribute *attr,
 728                           char *buf)
 729 {
 730         return sprintf(buf, "%d\n", 0);
 731 }
 732 static DEVICE_ATTR_RO(claim);
 733
 734 static struct attribute *rfkill_dev_attrs[] = {
 735         &dev_attr_name.attr,
 736         &dev_attr_type.attr,
 737         &dev_attr_index.attr,
 738         &dev_attr_persistent.attr,
 739         &dev_attr_state.attr,
 740         &dev_attr_claim.attr,
 741         &dev_attr_soft.attr,
 742         &dev_attr_hard.attr,
 743         NULL,
 744 };
 745 ATTRIBUTE_GROUPS(rfkill_dev);
 746
 747 static void rfkill_release(struct device *dev)
 748 {
 749         struct rfkill *rfkill = to_rfkill(dev);
 750
 751         kfree(rfkill);
 752 }
 753
 754 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 755 {
 756         struct rfkill *rfkill = to_rfkill(dev);
 757         unsigned long flags;
 758         u32 state;
 759         int error;
 760
 761         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 762         if (error)
 763                 return error;
 764         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 765                                rfkill_get_type_str(rfkill->type));
 766         if (error)
 767                 return error;
 768         spin_lock_irqsave(&rfkill->lock, flags);
 769         state = rfkill->state;
 770         spin_unlock_irqrestore(&rfkill->lock, flags);
 771         error = add_uevent_var(env, "RFKILL_STATE=%d",
 772                                user_state_from_blocked(state));
 773         return error;
 774 }
 775
 776 void rfkill_pause_polling(struct rfkill *rfkill)
 777 {
 778         BUG_ON(!rfkill);
 779
 780         if (!rfkill->ops->poll)
 781                 return;
 782
 783         cancel_delayed_work_sync(&rfkill->poll_work);
 784 }
 785 EXPORT_SYMBOL(rfkill_pause_polling);
 786
 787 void rfkill_resume_polling(struct rfkill *rfkill)
 788 {
 789         BUG_ON(!rfkill);
 790
 791         if (!rfkill->ops->poll)
 792                 return;
 793
 794         schedule_work(&rfkill->poll_work.work);
 795 }
 796 EXPORT_SYMBOL(rfkill_resume_polling);
 797
 798 static int rfkill_suspend(struct device *dev, pm_message_t state)
 799 {
 800         struct rfkill *rfkill = to_rfkill(dev);
 801
 802         rfkill_pause_polling(rfkill);
 803
 804         return 0;
 805 }
 806
 807 static int rfkill_resume(struct device *dev)
 808 {
 809         struct rfkill *rfkill = to_rfkill(dev);
 810         bool cur;
 811
 812         if (!rfkill->persistent) {
 813                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 814                 rfkill_set_block(rfkill, cur);
 815         }
 816
 817         rfkill_resume_polling(rfkill);
 818
 819         return 0;
 820 }
 821
 822 static struct class rfkill_class = {
 823         .name           = "rfkill",
 824         .dev_release    = rfkill_release,
 825         .dev_groups     = rfkill_dev_groups,
 826         .dev_uevent     = rfkill_dev_uevent,
 827         .suspend        = rfkill_suspend,
 828         .resume         = rfkill_resume,
 829 };
 830
 831 bool rfkill_blocked(struct rfkill *rfkill)
 832 {
 833         unsigned long flags;
 834         u32 state;
 835
 836         spin_lock_irqsave(&rfkill->lock, flags);
 837         state = rfkill->state;
 838         spin_unlock_irqrestore(&rfkill->lock, flags);
 839
 840         return !!(state & RFKILL_BLOCK_ANY);
 841 }
 842 EXPORT_SYMBOL(rfkill_blocked);
 843
 844
 845 struct rfkill * __must_check rfkill_alloc(const char *name,
 846                                           struct device *parent,
 847                                           const enum rfkill_type type,
 848                                           const struct rfkill_ops *ops,
 849                                           void *ops_data)
 850 {
 851         struct rfkill *rfkill;
 852         struct device *dev;
 853
 854         if (WARN_ON(!ops))
 855                 return NULL;
 856
 857         if (WARN_ON(!ops->set_block))
 858                 return NULL;
 859
 860         if (WARN_ON(!name))
 861                 return NULL;
 862
 863         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 864                 return NULL;
 865
 866         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
 867         if (!rfkill)
 868                 return NULL;
 869
 870         spin_lock_init(&rfkill->lock);
 871         INIT_LIST_HEAD(&rfkill->node);
 872         rfkill->type = type;
 873         rfkill->name = name;
 874         rfkill->ops = ops;
 875         rfkill->data = ops_data;
 876
 877         dev = &rfkill->dev;
 878         dev->class = &rfkill_class;
 879         dev->parent = parent;
 880         device_initialize(dev);
 881
 882         return rfkill;
 883 }
 884 EXPORT_SYMBOL(rfkill_alloc);
 885
 886 static void rfkill_poll(struct work_struct *work)
 887 {
 888         struct rfkill *rfkill;
 889
 890         rfkill = container_of(work, struct rfkill, poll_work.work);
 891
 892         /*
 893          * Poll hardware state -- driver will use one of the
 894          * rfkill_set{,_hw,_sw}_state functions and use its
 895          * return value to update the current status.
 896          */
 897         rfkill->ops->poll(rfkill, rfkill->data);
 898
 899         schedule_delayed_work(&rfkill->poll_work,
 900                 round_jiffies_relative(POLL_INTERVAL));
 901 }
 902
 903 static void rfkill_uevent_work(struct work_struct *work)
 904 {
 905         struct rfkill *rfkill;
 906
 907         rfkill = container_of(work, struct rfkill, uevent_work);
 908
 909         mutex_lock(&rfkill_global_mutex);
 910         rfkill_event(rfkill);
 911         mutex_unlock(&rfkill_global_mutex);
 912 }
 913
 914 static void rfkill_sync_work(struct work_struct *work)
 915 {
 916         struct rfkill *rfkill;
 917         bool cur;
 918
 919         rfkill = container_of(work, struct rfkill, sync_work);
 920
 921         mutex_lock(&rfkill_global_mutex);
 922         cur = rfkill_global_states[rfkill->type].cur;
 923         rfkill_set_block(rfkill, cur);
 924         mutex_unlock(&rfkill_global_mutex);
 925 }
 926
 927 int __must_check rfkill_register(struct rfkill *rfkill)
 928 {
 929         static unsigned long rfkill_no;
 930         struct device *dev = &rfkill->dev;
 931         int error;
 932
 933         BUG_ON(!rfkill);
 934
 935         mutex_lock(&rfkill_global_mutex);
 936
 937         if (rfkill->registered) {
 938                 error = -EALREADY;
 939                 goto unlock;
 940         }
 941
 942         rfkill->idx = rfkill_no;
 943         dev_set_name(dev, "rfkill%lu", rfkill_no);
 944         rfkill_no++;
 945
 946         list_add_tail(&rfkill->node, &rfkill_list);
 947
 948         error = device_add(dev);
 949         if (error)
 950                 goto remove;
 951
 952         error = rfkill_led_trigger_register(rfkill);
 953         if (error)
 954                 goto devdel;
 955
 956         rfkill->registered = true;
 957
 958         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 959         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 960         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 961
 962         if (rfkill->ops->poll)
 963                 schedule_delayed_work(&rfkill->poll_work,
 964                         round_jiffies_relative(POLL_INTERVAL));
 965
 966         if (!rfkill->persistent || rfkill_epo_lock_active) {
 967                 schedule_work(&rfkill->sync_work);
 968         } else {
 969 #ifdef CONFIG_RFKILL_INPUT
 970                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 971
 972                 if (!atomic_read(&rfkill_input_disabled))
 973                         __rfkill_switch_all(rfkill->type, soft_blocked);
 974 #endif
 975         }
 976
 977         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 978
 979         mutex_unlock(&rfkill_global_mutex);
 980         return 0;
 981
 982  devdel:
 983         device_del(&rfkill->dev);
 984  remove:
 985         list_del_init(&rfkill->node);
 986  unlock:
 987         mutex_unlock(&rfkill_global_mutex);
 988         return error;
 989 }
 990 EXPORT_SYMBOL(rfkill_register);
 991
 992 void rfkill_unregister(struct rfkill *rfkill)
 993 {
 994         BUG_ON(!rfkill);
 995
 996         if (rfkill->ops->poll)
 997                 cancel_delayed_work_sync(&rfkill->poll_work);
 998
 999         cancel_work_sync(&rfkill->uevent_work);
1000         cancel_work_sync(&rfkill->sync_work);
1001
1002         rfkill->registered = false;
1003
1004         device_del(&rfkill->dev);
1005
1006         mutex_lock(&rfkill_global_mutex);
1007         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1008         list_del_init(&rfkill->node);
1009         mutex_unlock(&rfkill_global_mutex);
1010
1011         rfkill_led_trigger_unregister(rfkill);
1012 }
1013 EXPORT_SYMBOL(rfkill_unregister);
1014
1015 void rfkill_destroy(struct rfkill *rfkill)
1016 {
1017         if (rfkill)
1018                 put_device(&rfkill->dev);
1019 }
1020 EXPORT_SYMBOL(rfkill_destroy);
1021
1022 static int rfkill_fop_open(struct inode *inode, struct file *file)
1023 {
1024         struct rfkill_data *data;
1025         struct rfkill *rfkill;
1026         struct rfkill_int_event *ev, *tmp;
1027
1028         data = kzalloc(sizeof(*data), GFP_KERNEL);
1029         if (!data)
1030                 return -ENOMEM;
1031
1032         INIT_LIST_HEAD(&data->events);
1033         mutex_init(&data->mtx);
1034         init_waitqueue_head(&data->read_wait);
1035
1036         mutex_lock(&rfkill_global_mutex);
1037         mutex_lock(&data->mtx);
1038         /*
1039          * start getting events from elsewhere but hold mtx to get
1040          * startup events added first
1041          */
1042
1043         list_for_each_entry(rfkill, &rfkill_list, node) {
1044                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1045                 if (!ev)
1046                         goto free;
1047                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1048                 list_add_tail(&ev->list, &data->events);
1049         }
1050         list_add(&data->list, &rfkill_fds);
1051         mutex_unlock(&data->mtx);
1052         mutex_unlock(&rfkill_global_mutex);
1053
1054         file->private_data = data;
1055
1056         return nonseekable_open(inode, file);
1057
1058  free:
1059         mutex_unlock(&data->mtx);
1060         mutex_unlock(&rfkill_global_mutex);
1061         mutex_destroy(&data->mtx);
1062         list_for_each_entry_safe(ev, tmp, &data->events, list)
1063                 kfree(ev);
1064         kfree(data);
1065         return -ENOMEM;
1066 }
1067
1068 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1069 {
1070         struct rfkill_data *data = file->private_data;
1071         unsigned int res = POLLOUT | POLLWRNORM;
1072
1073         poll_wait(file, &data->read_wait, wait);
1074
1075         mutex_lock(&data->mtx);
1076         if (!list_empty(&data->events))
1077                 res = POLLIN | POLLRDNORM;
1078         mutex_unlock(&data->mtx);
1079
1080         return res;
1081 }
1082
1083 static bool rfkill_readable(struct rfkill_data *data)
1084 {
1085         bool r;
1086
1087         mutex_lock(&data->mtx);
1088         r = !list_empty(&data->events);
1089         mutex_unlock(&data->mtx);
1090
1091         return r;
1092 }
1093
1094 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1095                                size_t count, loff_t *pos)
1096 {
1097         struct rfkill_data *data = file->private_data;
1098         struct rfkill_int_event *ev;
1099         unsigned long sz;
1100         int ret;
1101
1102         mutex_lock(&data->mtx);
1103
1104         while (list_empty(&data->events)) {
1105                 if (file->f_flags & O_NONBLOCK) {
1106                         ret = -EAGAIN;
1107                         goto out;
1108                 }
1109                 mutex_unlock(&data->mtx);
1110                 ret = wait_event_interruptible(data->read_wait,
1111                                                rfkill_readable(data));
1112                 mutex_lock(&data->mtx);
1113
1114                 if (ret)
1115                         goto out;
1116         }
1117
1118         ev = list_first_entry(&data->events, struct rfkill_int_event,
1119                                 list);
1120
1121         sz = min_t(unsigned long, sizeof(ev->ev), count);
1122         ret = sz;
1123         if (copy_to_user(buf, &ev->ev, sz))
1124                 ret = -EFAULT;
1125
1126         list_del(&ev->list);
1127         kfree(ev);
1128  out:
1129         mutex_unlock(&data->mtx);
1130         return ret;
1131 }
1132
1133 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1134                                 size_t count, loff_t *pos)
1135 {
1136         struct rfkill *rfkill;
1137         struct rfkill_event ev;
1138
1139         /* we don't need the 'hard' variable but accept it */
1140         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1141                 return -EINVAL;
1142
1143         /*
1144          * Copy as much data as we can accept into our 'ev' buffer,
1145          * but tell userspace how much we've copied so it can determine
1146          * our API version even in a write() call, if it cares.
1147          */
1148         count = min(count, sizeof(ev));
1149         if (copy_from_user(&ev, buf, count))
1150                 return -EFAULT;
1151
1152         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1153                 return -EINVAL;
1154
1155         if (ev.type >= NUM_RFKILL_TYPES)
1156                 return -EINVAL;
1157
1158         mutex_lock(&rfkill_global_mutex);
1159
1160         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1161                 if (ev.type == RFKILL_TYPE_ALL) {
1162                         enum rfkill_type i;
1163                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1164                                 rfkill_global_states[i].cur = ev.soft;
1165                 } else {
1166                         rfkill_global_states[ev.type].cur = ev.soft;
1167                 }
1168         }
1169
1170         list_for_each_entry(rfkill, &rfkill_list, node) {
1171                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1172                         continue;
1173
1174                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1175                         continue;
1176
1177                 rfkill_set_block(rfkill, ev.soft);
1178         }
1179         mutex_unlock(&rfkill_global_mutex);
1180
1181         return count;
1182 }
1183
1184 static int rfkill_fop_release(struct inode *inode, struct file *file)
1185 {
1186         struct rfkill_data *data = file->private_data;
1187         struct rfkill_int_event *ev, *tmp;
1188
1189         mutex_lock(&rfkill_global_mutex);
1190         list_del(&data->list);
1191         mutex_unlock(&rfkill_global_mutex);
1192
1193         mutex_destroy(&data->mtx);
1194         list_for_each_entry_safe(ev, tmp, &data->events, list)
1195                 kfree(ev);
1196
1197 #ifdef CONFIG_RFKILL_INPUT
1198         if (data->input_handler)
1199                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1200                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1201 #endif
1202
1203         kfree(data);
1204
1205         return 0;
1206 }
1207
1208 #ifdef CONFIG_RFKILL_INPUT
1209 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1210                              unsigned long arg)
1211 {
1212         struct rfkill_data *data = file->private_data;
1213
1214         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1215                 return -ENOSYS;
1216
1217         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1218                 return -ENOSYS;
1219
1220         mutex_lock(&data->mtx);
1221
1222         if (!data->input_handler) {
1223                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1224                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1225                 data->input_handler = true;
1226         }
1227
1228         mutex_unlock(&data->mtx);
1229
1230         return 0;
1231 }
1232 #endif
1233
1234 static const struct file_operations rfkill_fops = {
1235         .owner          = THIS_MODULE,
1236         .open           = rfkill_fop_open,
1237         .read           = rfkill_fop_read,
1238         .write          = rfkill_fop_write,
1239         .poll           = rfkill_fop_poll,
1240         .release        = rfkill_fop_release,
1241 #ifdef CONFIG_RFKILL_INPUT
1242         .unlocked_ioctl = rfkill_fop_ioctl,
1243         .compat_ioctl   = rfkill_fop_ioctl,
1244 #endif
1245         .llseek         = no_llseek,
1246 };
1247
1248 static struct miscdevice rfkill_miscdev = {
1249         .name   = "rfkill",
1250         .fops   = &rfkill_fops,
1251         .minor  = MISC_DYNAMIC_MINOR,
1252 };
1253
1254 static int __init rfkill_init(void)
1255 {
1256         int error;
1257         int i;
1258
1259         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1260                 rfkill_global_states[i].cur = !rfkill_default_state;
1261
1262         error = class_register(&rfkill_class);
1263         if (error)
1264                 goto out;
1265
1266         error = misc_register(&rfkill_miscdev);
1267         if (error) {
1268                 class_unregister(&rfkill_class);
1269                 goto out;
1270         }
1271
1272 #ifdef CONFIG_RFKILL_INPUT
1273         error = rfkill_handler_init();
1274         if (error) {
1275                 misc_deregister(&rfkill_miscdev);
1276                 class_unregister(&rfkill_class);
1277                 goto out;
1278         }
1279 #endif
1280
1281  out:
1282         return error;
1283 }
1284 subsys_initcall(rfkill_init);
1285
1286 static void __exit rfkill_exit(void)
1287 {
1288 #ifdef CONFIG_RFKILL_INPUT
1289         rfkill_handler_exit();
1290 #endif
1291         misc_deregister(&rfkill_miscdev);
1292         class_unregister(&rfkill_class);
1293 }
1294 module_exit(rfkill_exit);