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 int 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         return 0;
 153 }
 154
 155 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 156 {
 157         return rfkill->led_trigger.name;
 158 }
 159 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 160
 161 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 162 {
 163         BUG_ON(!rfkill);
 164
 165         rfkill->ledtrigname = name;
 166 }
 167 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 168
 169 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 170 {
 171         rfkill->led_trigger.name = rfkill->ledtrigname
 172                                         ? : dev_name(&rfkill->dev);
 173         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 174         return led_trigger_register(&rfkill->led_trigger);
 175 }
 176
 177 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 178 {
 179         led_trigger_unregister(&rfkill->led_trigger);
 180 }
 181
 182 static struct led_trigger rfkill_any_led_trigger;
 183 static struct led_trigger rfkill_none_led_trigger;
 184 static struct work_struct rfkill_global_led_trigger_work;
 185
 186 static void rfkill_global_led_trigger_worker(struct work_struct *work)
 187 {
 188         enum led_brightness brightness = LED_OFF;
 189         struct rfkill *rfkill;
 190
 191         mutex_lock(&rfkill_global_mutex);
 192         list_for_each_entry(rfkill, &rfkill_list, node) {
 193                 if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
 194                         brightness = LED_FULL;
 195                         break;
 196                 }
 197         }
 198         mutex_unlock(&rfkill_global_mutex);
 199
 200         led_trigger_event(&rfkill_any_led_trigger, brightness);
 201         led_trigger_event(&rfkill_none_led_trigger,
 202                           brightness == LED_OFF ? LED_FULL : LED_OFF);
 203 }
 204
 205 static void rfkill_global_led_trigger_event(void)
 206 {
 207         schedule_work(&rfkill_global_led_trigger_work);
 208 }
 209
 210 static int rfkill_global_led_trigger_register(void)
 211 {
 212         int ret;
 213
 214         INIT_WORK(&rfkill_global_led_trigger_work,
 215                         rfkill_global_led_trigger_worker);
 216
 217         rfkill_any_led_trigger.name = "rfkill-any";
 218         ret = led_trigger_register(&rfkill_any_led_trigger);
 219         if (ret)
 220                 return ret;
 221
 222         rfkill_none_led_trigger.name = "rfkill-none";
 223         ret = led_trigger_register(&rfkill_none_led_trigger);
 224         if (ret)
 225                 led_trigger_unregister(&rfkill_any_led_trigger);
 226         else
 227                 /* Delay activation until all global triggers are registered */
 228                 rfkill_global_led_trigger_event();
 229
 230         return ret;
 231 }
 232
 233 static void rfkill_global_led_trigger_unregister(void)
 234 {
 235         led_trigger_unregister(&rfkill_none_led_trigger);
 236         led_trigger_unregister(&rfkill_any_led_trigger);
 237         cancel_work_sync(&rfkill_global_led_trigger_work);
 238 }
 239 #else
 240 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 241 {
 242 }
 243
 244 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 245 {
 246         return 0;
 247 }
 248
 249 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 250 {
 251 }
 252
 253 static void rfkill_global_led_trigger_event(void)
 254 {
 255 }
 256
 257 static int rfkill_global_led_trigger_register(void)
 258 {
 259         return 0;
 260 }
 261
 262 static void rfkill_global_led_trigger_unregister(void)
 263 {
 264 }
 265 #endif /* CONFIG_RFKILL_LEDS */
 266
 267 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 268                               enum rfkill_operation op)
 269 {
 270         unsigned long flags;
 271
 272         ev->idx = rfkill->idx;
 273         ev->type = rfkill->type;
 274         ev->op = op;
 275
 276         spin_lock_irqsave(&rfkill->lock, flags);
 277         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 278         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 279                                         RFKILL_BLOCK_SW_PREV));
 280         spin_unlock_irqrestore(&rfkill->lock, flags);
 281 }
 282
 283 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 284 {
 285         struct rfkill_data *data;
 286         struct rfkill_int_event *ev;
 287
 288         list_for_each_entry(data, &rfkill_fds, list) {
 289                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 290                 if (!ev)
 291                         continue;
 292                 rfkill_fill_event(&ev->ev, rfkill, op);
 293                 mutex_lock(&data->mtx);
 294                 list_add_tail(&ev->list, &data->events);
 295                 mutex_unlock(&data->mtx);
 296                 wake_up_interruptible(&data->read_wait);
 297         }
 298 }
 299
 300 static void rfkill_event(struct rfkill *rfkill)
 301 {
 302         if (!rfkill->registered)
 303                 return;
 304
 305         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 306
 307         /* also send event to /dev/rfkill */
 308         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 309 }
 310
 311 /**
 312  * rfkill_set_block - wrapper for set_block method
 313  *
 314  * @rfkill: the rfkill struct to use
 315  * @blocked: the new software state
 316  *
 317  * Calls the set_block method (when applicable) and handles notifications
 318  * etc. as well.
 319  */
 320 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 321 {
 322         unsigned long flags;
 323         bool prev, curr;
 324         int err;
 325
 326         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 327                 return;
 328
 329         /*
 330          * Some platforms (...!) generate input events which affect the
 331          * _hard_ kill state -- whenever something tries to change the
 332          * current software state query the hardware state too.
 333          */
 334         if (rfkill->ops->query)
 335                 rfkill->ops->query(rfkill, rfkill->data);
 336
 337         spin_lock_irqsave(&rfkill->lock, flags);
 338         prev = rfkill->state & RFKILL_BLOCK_SW;
 339
 340         if (prev)
 341                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 342         else
 343                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 344
 345         if (blocked)
 346                 rfkill->state |= RFKILL_BLOCK_SW;
 347         else
 348                 rfkill->state &= ~RFKILL_BLOCK_SW;
 349
 350         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 351         spin_unlock_irqrestore(&rfkill->lock, flags);
 352
 353         err = rfkill->ops->set_block(rfkill->data, blocked);
 354
 355         spin_lock_irqsave(&rfkill->lock, flags);
 356         if (err) {
 357                 /*
 358                  * Failed -- reset status to _PREV, which may be different
 359                  * from what we have set _PREV to earlier in this function
 360                  * if rfkill_set_sw_state was invoked.
 361                  */
 362                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 363                         rfkill->state |= RFKILL_BLOCK_SW;
 364                 else
 365                         rfkill->state &= ~RFKILL_BLOCK_SW;
 366         }
 367         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 368         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 369         curr = rfkill->state & RFKILL_BLOCK_SW;
 370         spin_unlock_irqrestore(&rfkill->lock, flags);
 371
 372         rfkill_led_trigger_event(rfkill);
 373         rfkill_global_led_trigger_event();
 374
 375         if (prev != curr)
 376                 rfkill_event(rfkill);
 377 }
 378
 379 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
 380 {
 381         int i;
 382
 383         if (type != RFKILL_TYPE_ALL) {
 384                 rfkill_global_states[type].cur = blocked;
 385                 return;
 386         }
 387
 388         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 389                 rfkill_global_states[i].cur = blocked;
 390 }
 391
 392 #ifdef CONFIG_RFKILL_INPUT
 393 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 394
 395 /**
 396  * __rfkill_switch_all - Toggle state of all switches of given type
 397  * @type: type of interfaces to be affected
 398  * @blocked: the new state
 399  *
 400  * This function sets the state of all switches of given type,
 401  * unless a specific switch is suspended.
 402  *
 403  * Caller must have acquired rfkill_global_mutex.
 404  */
 405 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 406 {
 407         struct rfkill *rfkill;
 408
 409         rfkill_update_global_state(type, blocked);
 410         list_for_each_entry(rfkill, &rfkill_list, node) {
 411                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 412                         continue;
 413
 414                 rfkill_set_block(rfkill, blocked);
 415         }
 416 }
 417
 418 /**
 419  * rfkill_switch_all - Toggle state of all switches of given type
 420  * @type: type of interfaces to be affected
 421  * @blocked: the new state
 422  *
 423  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 424  * Please refer to __rfkill_switch_all() for details.
 425  *
 426  * Does nothing if the EPO lock is active.
 427  */
 428 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 429 {
 430         if (atomic_read(&rfkill_input_disabled))
 431                 return;
 432
 433         mutex_lock(&rfkill_global_mutex);
 434
 435         if (!rfkill_epo_lock_active)
 436                 __rfkill_switch_all(type, blocked);
 437
 438         mutex_unlock(&rfkill_global_mutex);
 439 }
 440
 441 /**
 442  * rfkill_epo - emergency power off all transmitters
 443  *
 444  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 445  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 446  *
 447  * The global state before the EPO is saved and can be restored later
 448  * using rfkill_restore_states().
 449  */
 450 void rfkill_epo(void)
 451 {
 452         struct rfkill *rfkill;
 453         int i;
 454
 455         if (atomic_read(&rfkill_input_disabled))
 456                 return;
 457
 458         mutex_lock(&rfkill_global_mutex);
 459
 460         rfkill_epo_lock_active = true;
 461         list_for_each_entry(rfkill, &rfkill_list, node)
 462                 rfkill_set_block(rfkill, true);
 463
 464         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 465                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 466                 rfkill_global_states[i].cur = true;
 467         }
 468
 469         mutex_unlock(&rfkill_global_mutex);
 470 }
 471
 472 /**
 473  * rfkill_restore_states - restore global states
 474  *
 475  * Restore (and sync switches to) the global state from the
 476  * states in rfkill_default_states.  This can undo the effects of
 477  * a call to rfkill_epo().
 478  */
 479 void rfkill_restore_states(void)
 480 {
 481         int i;
 482
 483         if (atomic_read(&rfkill_input_disabled))
 484                 return;
 485
 486         mutex_lock(&rfkill_global_mutex);
 487
 488         rfkill_epo_lock_active = false;
 489         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 490                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 491         mutex_unlock(&rfkill_global_mutex);
 492 }
 493
 494 /**
 495  * rfkill_remove_epo_lock - unlock state changes
 496  *
 497  * Used by rfkill-input manually unlock state changes, when
 498  * the EPO switch is deactivated.
 499  */
 500 void rfkill_remove_epo_lock(void)
 501 {
 502         if (atomic_read(&rfkill_input_disabled))
 503                 return;
 504
 505         mutex_lock(&rfkill_global_mutex);
 506         rfkill_epo_lock_active = false;
 507         mutex_unlock(&rfkill_global_mutex);
 508 }
 509
 510 /**
 511  * rfkill_is_epo_lock_active - returns true EPO is active
 512  *
 513  * Returns 0 (false) if there is NOT an active EPO condition,
 514  * and 1 (true) if there is an active EPO condition, which
 515  * locks all radios in one of the BLOCKED states.
 516  *
 517  * Can be called in atomic context.
 518  */
 519 bool rfkill_is_epo_lock_active(void)
 520 {
 521         return rfkill_epo_lock_active;
 522 }
 523
 524 /**
 525  * rfkill_get_global_sw_state - returns global state for a type
 526  * @type: the type to get the global state of
 527  *
 528  * Returns the current global state for a given wireless
 529  * device type.
 530  */
 531 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 532 {
 533         return rfkill_global_states[type].cur;
 534 }
 535 #endif
 536
 537 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 538 {
 539         unsigned long flags;
 540         bool ret, prev;
 541
 542         BUG_ON(!rfkill);
 543
 544         spin_lock_irqsave(&rfkill->lock, flags);
 545         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 546         if (blocked)
 547                 rfkill->state |= RFKILL_BLOCK_HW;
 548         else
 549                 rfkill->state &= ~RFKILL_BLOCK_HW;
 550         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
 551         spin_unlock_irqrestore(&rfkill->lock, flags);
 552
 553         rfkill_led_trigger_event(rfkill);
 554         rfkill_global_led_trigger_event();
 555
 556         if (rfkill->registered && prev != blocked)
 557                 schedule_work(&rfkill->uevent_work);
 558
 559         return ret;
 560 }
 561 EXPORT_SYMBOL(rfkill_set_hw_state);
 562
 563 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 564 {
 565         u32 bit = RFKILL_BLOCK_SW;
 566
 567         /* if in a ops->set_block right now, use other bit */
 568         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 569                 bit = RFKILL_BLOCK_SW_PREV;
 570
 571         if (blocked)
 572                 rfkill->state |= bit;
 573         else
 574                 rfkill->state &= ~bit;
 575 }
 576
 577 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 578 {
 579         unsigned long flags;
 580         bool prev, hwblock;
 581
 582         BUG_ON(!rfkill);
 583
 584         spin_lock_irqsave(&rfkill->lock, flags);
 585         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 586         __rfkill_set_sw_state(rfkill, blocked);
 587         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 588         blocked = blocked || hwblock;
 589         spin_unlock_irqrestore(&rfkill->lock, flags);
 590
 591         if (!rfkill->registered)
 592                 return blocked;
 593
 594         if (prev != blocked && !hwblock)
 595                 schedule_work(&rfkill->uevent_work);
 596
 597         rfkill_led_trigger_event(rfkill);
 598         rfkill_global_led_trigger_event();
 599
 600         return blocked;
 601 }
 602 EXPORT_SYMBOL(rfkill_set_sw_state);
 603
 604 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 605 {
 606         unsigned long flags;
 607
 608         BUG_ON(!rfkill);
 609         BUG_ON(rfkill->registered);
 610
 611         spin_lock_irqsave(&rfkill->lock, flags);
 612         __rfkill_set_sw_state(rfkill, blocked);
 613         rfkill->persistent = true;
 614         spin_unlock_irqrestore(&rfkill->lock, flags);
 615 }
 616 EXPORT_SYMBOL(rfkill_init_sw_state);
 617
 618 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 619 {
 620         unsigned long flags;
 621         bool swprev, hwprev;
 622
 623         BUG_ON(!rfkill);
 624
 625         spin_lock_irqsave(&rfkill->lock, flags);
 626
 627         /*
 628          * No need to care about prev/setblock ... this is for uevent only
 629          * and that will get triggered by rfkill_set_block anyway.
 630          */
 631         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 632         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 633         __rfkill_set_sw_state(rfkill, sw);
 634         if (hw)
 635                 rfkill->state |= RFKILL_BLOCK_HW;
 636         else
 637                 rfkill->state &= ~RFKILL_BLOCK_HW;
 638
 639         spin_unlock_irqrestore(&rfkill->lock, flags);
 640
 641         if (!rfkill->registered) {
 642                 rfkill->persistent = true;
 643         } else {
 644                 if (swprev != sw || hwprev != hw)
 645                         schedule_work(&rfkill->uevent_work);
 646
 647                 rfkill_led_trigger_event(rfkill);
 648                 rfkill_global_led_trigger_event();
 649         }
 650 }
 651 EXPORT_SYMBOL(rfkill_set_states);
 652
 653 static const char * const rfkill_types[] = {
 654         NULL, /* RFKILL_TYPE_ALL */
 655         "wlan",
 656         "bluetooth",
 657         "ultrawideband",
 658         "wimax",
 659         "wwan",
 660         "gps",
 661         "fm",
 662         "nfc",
 663 };
 664
 665 enum rfkill_type rfkill_find_type(const char *name)
 666 {
 667         int i;
 668
 669         BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
 670
 671         if (!name)
 672                 return RFKILL_TYPE_ALL;
 673
 674         for (i = 1; i < NUM_RFKILL_TYPES; i++)
 675                 if (!strcmp(name, rfkill_types[i]))
 676                         return i;
 677         return RFKILL_TYPE_ALL;
 678 }
 679 EXPORT_SYMBOL(rfkill_find_type);
 680
 681 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 682                          char *buf)
 683 {
 684         struct rfkill *rfkill = to_rfkill(dev);
 685
 686         return sprintf(buf, "%s\n", rfkill->name);
 687 }
 688 static DEVICE_ATTR_RO(name);
 689
 690 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 691                          char *buf)
 692 {
 693         struct rfkill *rfkill = to_rfkill(dev);
 694
 695         return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
 696 }
 697 static DEVICE_ATTR_RO(type);
 698
 699 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 700                           char *buf)
 701 {
 702         struct rfkill *rfkill = to_rfkill(dev);
 703
 704         return sprintf(buf, "%d\n", rfkill->idx);
 705 }
 706 static DEVICE_ATTR_RO(index);
 707
 708 static ssize_t persistent_show(struct device *dev,
 709                                struct device_attribute *attr, char *buf)
 710 {
 711         struct rfkill *rfkill = to_rfkill(dev);
 712
 713         return sprintf(buf, "%d\n", rfkill->persistent);
 714 }
 715 static DEVICE_ATTR_RO(persistent);
 716
 717 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 718                          char *buf)
 719 {
 720         struct rfkill *rfkill = to_rfkill(dev);
 721
 722         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 723 }
 724 static DEVICE_ATTR_RO(hard);
 725
 726 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 727                          char *buf)
 728 {
 729         struct rfkill *rfkill = to_rfkill(dev);
 730
 731         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 732 }
 733
 734 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 735                           const char *buf, size_t count)
 736 {
 737         struct rfkill *rfkill = to_rfkill(dev);
 738         unsigned long state;
 739         int err;
 740
 741         if (!capable(CAP_NET_ADMIN))
 742                 return -EPERM;
 743
 744         err = kstrtoul(buf, 0, &state);
 745         if (err)
 746                 return err;
 747
 748         if (state > 1 )
 749                 return -EINVAL;
 750
 751         mutex_lock(&rfkill_global_mutex);
 752         rfkill_set_block(rfkill, state);
 753         mutex_unlock(&rfkill_global_mutex);
 754
 755         return count;
 756 }
 757 static DEVICE_ATTR_RW(soft);
 758
 759 static u8 user_state_from_blocked(unsigned long state)
 760 {
 761         if (state & RFKILL_BLOCK_HW)
 762                 return RFKILL_USER_STATE_HARD_BLOCKED;
 763         if (state & RFKILL_BLOCK_SW)
 764                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 765
 766         return RFKILL_USER_STATE_UNBLOCKED;
 767 }
 768
 769 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 770                           char *buf)
 771 {
 772         struct rfkill *rfkill = to_rfkill(dev);
 773
 774         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 775 }
 776
 777 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 778                            const char *buf, size_t count)
 779 {
 780         struct rfkill *rfkill = to_rfkill(dev);
 781         unsigned long state;
 782         int err;
 783
 784         if (!capable(CAP_NET_ADMIN))
 785                 return -EPERM;
 786
 787         err = kstrtoul(buf, 0, &state);
 788         if (err)
 789                 return err;
 790
 791         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 792             state != RFKILL_USER_STATE_UNBLOCKED)
 793                 return -EINVAL;
 794
 795         mutex_lock(&rfkill_global_mutex);
 796         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 797         mutex_unlock(&rfkill_global_mutex);
 798
 799         return count;
 800 }
 801 static DEVICE_ATTR_RW(state);
 802
 803 static struct attribute *rfkill_dev_attrs[] = {
 804         &dev_attr_name.attr,
 805         &dev_attr_type.attr,
 806         &dev_attr_index.attr,
 807         &dev_attr_persistent.attr,
 808         &dev_attr_state.attr,
 809         &dev_attr_soft.attr,
 810         &dev_attr_hard.attr,
 811         NULL,
 812 };
 813 ATTRIBUTE_GROUPS(rfkill_dev);
 814
 815 static void rfkill_release(struct device *dev)
 816 {
 817         struct rfkill *rfkill = to_rfkill(dev);
 818
 819         kfree(rfkill);
 820 }
 821
 822 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 823 {
 824         struct rfkill *rfkill = to_rfkill(dev);
 825         unsigned long flags;
 826         u32 state;
 827         int error;
 828
 829         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 830         if (error)
 831                 return error;
 832         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 833                                rfkill_types[rfkill->type]);
 834         if (error)
 835                 return error;
 836         spin_lock_irqsave(&rfkill->lock, flags);
 837         state = rfkill->state;
 838         spin_unlock_irqrestore(&rfkill->lock, flags);
 839         error = add_uevent_var(env, "RFKILL_STATE=%d",
 840                                user_state_from_blocked(state));
 841         return error;
 842 }
 843
 844 void rfkill_pause_polling(struct rfkill *rfkill)
 845 {
 846         BUG_ON(!rfkill);
 847
 848         if (!rfkill->ops->poll)
 849                 return;
 850
 851         rfkill->polling_paused = true;
 852         cancel_delayed_work_sync(&rfkill->poll_work);
 853 }
 854 EXPORT_SYMBOL(rfkill_pause_polling);
 855
 856 void rfkill_resume_polling(struct rfkill *rfkill)
 857 {
 858         BUG_ON(!rfkill);
 859
 860         if (!rfkill->ops->poll)
 861                 return;
 862
 863         rfkill->polling_paused = false;
 864
 865         if (rfkill->suspended)
 866                 return;
 867
 868         queue_delayed_work(system_power_efficient_wq,
 869                            &rfkill->poll_work, 0);
 870 }
 871 EXPORT_SYMBOL(rfkill_resume_polling);
 872
 873 #ifdef CONFIG_PM_SLEEP
 874 static int rfkill_suspend(struct device *dev)
 875 {
 876         struct rfkill *rfkill = to_rfkill(dev);
 877
 878         rfkill->suspended = true;
 879         cancel_delayed_work_sync(&rfkill->poll_work);
 880
 881         return 0;
 882 }
 883
 884 static int rfkill_resume(struct device *dev)
 885 {
 886         struct rfkill *rfkill = to_rfkill(dev);
 887         bool cur;
 888
 889         rfkill->suspended = false;
 890
 891         if (!rfkill->persistent) {
 892                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 893                 rfkill_set_block(rfkill, cur);
 894         }
 895
 896         if (rfkill->ops->poll && !rfkill->polling_paused)
 897                 queue_delayed_work(system_power_efficient_wq,
 898                                    &rfkill->poll_work, 0);
 899
 900         return 0;
 901 }
 902
 903 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 904 #define RFKILL_PM_OPS (&rfkill_pm_ops)
 905 #else
 906 #define RFKILL_PM_OPS NULL
 907 #endif
 908
 909 static struct class rfkill_class = {
 910         .name           = "rfkill",
 911         .dev_release    = rfkill_release,
 912         .dev_groups     = rfkill_dev_groups,
 913         .dev_uevent     = rfkill_dev_uevent,
 914         .pm             = RFKILL_PM_OPS,
 915 };
 916
 917 bool rfkill_blocked(struct rfkill *rfkill)
 918 {
 919         unsigned long flags;
 920         u32 state;
 921
 922         spin_lock_irqsave(&rfkill->lock, flags);
 923         state = rfkill->state;
 924         spin_unlock_irqrestore(&rfkill->lock, flags);
 925
 926         return !!(state & RFKILL_BLOCK_ANY);
 927 }
 928 EXPORT_SYMBOL(rfkill_blocked);
 929
 930
 931 struct rfkill * __must_check rfkill_alloc(const char *name,
 932                                           struct device *parent,
 933                                           const enum rfkill_type type,
 934                                           const struct rfkill_ops *ops,
 935                                           void *ops_data)
 936 {
 937         struct rfkill *rfkill;
 938         struct device *dev;
 939
 940         if (WARN_ON(!ops))
 941                 return NULL;
 942
 943         if (WARN_ON(!ops->set_block))
 944                 return NULL;
 945
 946         if (WARN_ON(!name))
 947                 return NULL;
 948
 949         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 950                 return NULL;
 951
 952         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 953         if (!rfkill)
 954                 return NULL;
 955
 956         spin_lock_init(&rfkill->lock);
 957         INIT_LIST_HEAD(&rfkill->node);
 958         rfkill->type = type;
 959         strcpy(rfkill->name, name);
 960         rfkill->ops = ops;
 961         rfkill->data = ops_data;
 962
 963         dev = &rfkill->dev;
 964         dev->class = &rfkill_class;
 965         dev->parent = parent;
 966         device_initialize(dev);
 967
 968         return rfkill;
 969 }
 970 EXPORT_SYMBOL(rfkill_alloc);
 971
 972 static void rfkill_poll(struct work_struct *work)
 973 {
 974         struct rfkill *rfkill;
 975
 976         rfkill = container_of(work, struct rfkill, poll_work.work);
 977
 978         /*
 979          * Poll hardware state -- driver will use one of the
 980          * rfkill_set{,_hw,_sw}_state functions and use its
 981          * return value to update the current status.
 982          */
 983         rfkill->ops->poll(rfkill, rfkill->data);
 984
 985         queue_delayed_work(system_power_efficient_wq,
 986                 &rfkill->poll_work,
 987                 round_jiffies_relative(POLL_INTERVAL));
 988 }
 989
 990 static void rfkill_uevent_work(struct work_struct *work)
 991 {
 992         struct rfkill *rfkill;
 993
 994         rfkill = container_of(work, struct rfkill, uevent_work);
 995
 996         mutex_lock(&rfkill_global_mutex);
 997         rfkill_event(rfkill);
 998         mutex_unlock(&rfkill_global_mutex);
 999 }
1000
1001 static void rfkill_sync_work(struct work_struct *work)
1002 {
1003         struct rfkill *rfkill;
1004         bool cur;
1005
1006         rfkill = container_of(work, struct rfkill, sync_work);
1007
1008         mutex_lock(&rfkill_global_mutex);
1009         cur = rfkill_global_states[rfkill->type].cur;
1010         rfkill_set_block(rfkill, cur);
1011         mutex_unlock(&rfkill_global_mutex);
1012 }
1013
1014 int __must_check rfkill_register(struct rfkill *rfkill)
1015 {
1016         static unsigned long rfkill_no;
1017         struct device *dev = &rfkill->dev;
1018         int error;
1019
1020         BUG_ON(!rfkill);
1021
1022         mutex_lock(&rfkill_global_mutex);
1023
1024         if (rfkill->registered) {
1025                 error = -EALREADY;
1026                 goto unlock;
1027         }
1028
1029         rfkill->idx = rfkill_no;
1030         dev_set_name(dev, "rfkill%lu", rfkill_no);
1031         rfkill_no++;
1032
1033         list_add_tail(&rfkill->node, &rfkill_list);
1034
1035         error = device_add(dev);
1036         if (error)
1037                 goto remove;
1038
1039         error = rfkill_led_trigger_register(rfkill);
1040         if (error)
1041                 goto devdel;
1042
1043         rfkill->registered = true;
1044
1045         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
1046         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
1047         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
1048
1049         if (rfkill->ops->poll)
1050                 queue_delayed_work(system_power_efficient_wq,
1051                         &rfkill->poll_work,
1052                         round_jiffies_relative(POLL_INTERVAL));
1053
1054         if (!rfkill->persistent || rfkill_epo_lock_active) {
1055                 schedule_work(&rfkill->sync_work);
1056         } else {
1057 #ifdef CONFIG_RFKILL_INPUT
1058                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
1059
1060                 if (!atomic_read(&rfkill_input_disabled))
1061                         __rfkill_switch_all(rfkill->type, soft_blocked);
1062 #endif
1063         }
1064
1065         rfkill_global_led_trigger_event();
1066         rfkill_send_events(rfkill, RFKILL_OP_ADD);
1067
1068         mutex_unlock(&rfkill_global_mutex);
1069         return 0;
1070
1071  devdel:
1072         device_del(&rfkill->dev);
1073  remove:
1074         list_del_init(&rfkill->node);
1075  unlock:
1076         mutex_unlock(&rfkill_global_mutex);
1077         return error;
1078 }
1079 EXPORT_SYMBOL(rfkill_register);
1080
1081 void rfkill_unregister(struct rfkill *rfkill)
1082 {
1083         BUG_ON(!rfkill);
1084
1085         if (rfkill->ops->poll)
1086                 cancel_delayed_work_sync(&rfkill->poll_work);
1087
1088         cancel_work_sync(&rfkill->uevent_work);
1089         cancel_work_sync(&rfkill->sync_work);
1090
1091         rfkill->registered = false;
1092
1093         device_del(&rfkill->dev);
1094
1095         mutex_lock(&rfkill_global_mutex);
1096         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1097         list_del_init(&rfkill->node);
1098         rfkill_global_led_trigger_event();
1099         mutex_unlock(&rfkill_global_mutex);
1100
1101         rfkill_led_trigger_unregister(rfkill);
1102 }
1103 EXPORT_SYMBOL(rfkill_unregister);
1104
1105 void rfkill_destroy(struct rfkill *rfkill)
1106 {
1107         if (rfkill)
1108                 put_device(&rfkill->dev);
1109 }
1110 EXPORT_SYMBOL(rfkill_destroy);
1111
1112 static int rfkill_fop_open(struct inode *inode, struct file *file)
1113 {
1114         struct rfkill_data *data;
1115         struct rfkill *rfkill;
1116         struct rfkill_int_event *ev, *tmp;
1117
1118         data = kzalloc(sizeof(*data), GFP_KERNEL);
1119         if (!data)
1120                 return -ENOMEM;
1121
1122         INIT_LIST_HEAD(&data->events);
1123         mutex_init(&data->mtx);
1124         init_waitqueue_head(&data->read_wait);
1125
1126         mutex_lock(&rfkill_global_mutex);
1127         mutex_lock(&data->mtx);
1128         /*
1129          * start getting events from elsewhere but hold mtx to get
1130          * startup events added first
1131          */
1132
1133         list_for_each_entry(rfkill, &rfkill_list, node) {
1134                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1135                 if (!ev)
1136                         goto free;
1137                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1138                 list_add_tail(&ev->list, &data->events);
1139         }
1140         list_add(&data->list, &rfkill_fds);
1141         mutex_unlock(&data->mtx);
1142         mutex_unlock(&rfkill_global_mutex);
1143
1144         file->private_data = data;
1145
1146         return nonseekable_open(inode, file);
1147
1148  free:
1149         mutex_unlock(&data->mtx);
1150         mutex_unlock(&rfkill_global_mutex);
1151         mutex_destroy(&data->mtx);
1152         list_for_each_entry_safe(ev, tmp, &data->events, list)
1153                 kfree(ev);
1154         kfree(data);
1155         return -ENOMEM;
1156 }
1157
1158 static __poll_t rfkill_fop_poll(struct file *file, poll_table *wait)
1159 {
1160         struct rfkill_data *data = file->private_data;
1161         __poll_t res = EPOLLOUT | EPOLLWRNORM;
1162
1163         poll_wait(file, &data->read_wait, wait);
1164
1165         mutex_lock(&data->mtx);
1166         if (!list_empty(&data->events))
1167                 res = EPOLLIN | EPOLLRDNORM;
1168         mutex_unlock(&data->mtx);
1169
1170         return res;
1171 }
1172
1173 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1174                                size_t count, loff_t *pos)
1175 {
1176         struct rfkill_data *data = file->private_data;
1177         struct rfkill_int_event *ev;
1178         unsigned long sz;
1179         int ret;
1180
1181         mutex_lock(&data->mtx);
1182
1183         while (list_empty(&data->events)) {
1184                 if (file->f_flags & O_NONBLOCK) {
1185                         ret = -EAGAIN;
1186                         goto out;
1187                 }
1188                 mutex_unlock(&data->mtx);
1189                 /* since we re-check and it just compares pointers,
1190                  * using !list_empty() without locking isn't a problem
1191                  */
1192                 ret = wait_event_interruptible(data->read_wait,
1193                                                !list_empty(&data->events));
1194                 mutex_lock(&data->mtx);
1195
1196                 if (ret)
1197                         goto out;
1198         }
1199
1200         ev = list_first_entry(&data->events, struct rfkill_int_event,
1201                                 list);
1202
1203         sz = min_t(unsigned long, sizeof(ev->ev), count);
1204         ret = sz;
1205         if (copy_to_user(buf, &ev->ev, sz))
1206                 ret = -EFAULT;
1207
1208         list_del(&ev->list);
1209         kfree(ev);
1210  out:
1211         mutex_unlock(&data->mtx);
1212         return ret;
1213 }
1214
1215 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1216                                 size_t count, loff_t *pos)
1217 {
1218         struct rfkill *rfkill;
1219         struct rfkill_event ev;
1220         int ret;
1221
1222         /* we don't need the 'hard' variable but accept it */
1223         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1224                 return -EINVAL;
1225
1226         /*
1227          * Copy as much data as we can accept into our 'ev' buffer,
1228          * but tell userspace how much we've copied so it can determine
1229          * our API version even in a write() call, if it cares.
1230          */
1231         count = min(count, sizeof(ev));
1232         if (copy_from_user(&ev, buf, count))
1233                 return -EFAULT;
1234
1235         if (ev.type >= NUM_RFKILL_TYPES)
1236                 return -EINVAL;
1237
1238         mutex_lock(&rfkill_global_mutex);
1239
1240         switch (ev.op) {
1241         case RFKILL_OP_CHANGE_ALL:
1242                 rfkill_update_global_state(ev.type, ev.soft);
1243                 list_for_each_entry(rfkill, &rfkill_list, node)
1244                         if (rfkill->type == ev.type ||
1245                             ev.type == RFKILL_TYPE_ALL)
1246                                 rfkill_set_block(rfkill, ev.soft);
1247                 ret = 0;
1248                 break;
1249         case RFKILL_OP_CHANGE:
1250                 list_for_each_entry(rfkill, &rfkill_list, node)
1251                         if (rfkill->idx == ev.idx &&
1252                             (rfkill->type == ev.type ||
1253                              ev.type == RFKILL_TYPE_ALL))
1254                                 rfkill_set_block(rfkill, ev.soft);
1255                 ret = 0;
1256                 break;
1257         default:
1258                 ret = -EINVAL;
1259                 break;
1260         }
1261
1262         mutex_unlock(&rfkill_global_mutex);
1263
1264         return ret ?: count;
1265 }
1266
1267 static int rfkill_fop_release(struct inode *inode, struct file *file)
1268 {
1269         struct rfkill_data *data = file->private_data;
1270         struct rfkill_int_event *ev, *tmp;
1271
1272         mutex_lock(&rfkill_global_mutex);
1273         list_del(&data->list);
1274         mutex_unlock(&rfkill_global_mutex);
1275
1276         mutex_destroy(&data->mtx);
1277         list_for_each_entry_safe(ev, tmp, &data->events, list)
1278                 kfree(ev);
1279
1280 #ifdef CONFIG_RFKILL_INPUT
1281         if (data->input_handler)
1282                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1283                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1284 #endif
1285
1286         kfree(data);
1287
1288         return 0;
1289 }
1290
1291 #ifdef CONFIG_RFKILL_INPUT
1292 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1293                              unsigned long arg)
1294 {
1295         struct rfkill_data *data = file->private_data;
1296
1297         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1298                 return -ENOSYS;
1299
1300         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1301                 return -ENOSYS;
1302
1303         mutex_lock(&data->mtx);
1304
1305         if (!data->input_handler) {
1306                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1307                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1308                 data->input_handler = true;
1309         }
1310
1311         mutex_unlock(&data->mtx);
1312
1313         return 0;
1314 }
1315 #endif
1316
1317 static const struct file_operations rfkill_fops = {
1318         .owner          = THIS_MODULE,
1319         .open           = rfkill_fop_open,
1320         .read           = rfkill_fop_read,
1321         .write          = rfkill_fop_write,
1322         .poll           = rfkill_fop_poll,
1323         .release        = rfkill_fop_release,
1324 #ifdef CONFIG_RFKILL_INPUT
1325         .unlocked_ioctl = rfkill_fop_ioctl,
1326         .compat_ioctl   = rfkill_fop_ioctl,
1327 #endif
1328         .llseek         = no_llseek,
1329 };
1330
1331 static struct miscdevice rfkill_miscdev = {
1332         .name   = "rfkill",
1333         .fops   = &rfkill_fops,
1334         .minor  = MISC_DYNAMIC_MINOR,
1335 };
1336
1337 static int __init rfkill_init(void)
1338 {
1339         int error;
1340
1341         rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1342
1343         error = class_register(&rfkill_class);
1344         if (error)
1345                 goto error_class;
1346
1347         error = misc_register(&rfkill_miscdev);
1348         if (error)
1349                 goto error_misc;
1350
1351         error = rfkill_global_led_trigger_register();
1352         if (error)
1353                 goto error_led_trigger;
1354
1355 #ifdef CONFIG_RFKILL_INPUT
1356         error = rfkill_handler_init();
1357         if (error)
1358                 goto error_input;
1359 #endif
1360
1361         return 0;
1362
1363 #ifdef CONFIG_RFKILL_INPUT
1364 error_input:
1365         rfkill_global_led_trigger_unregister();
1366 #endif
1367 error_led_trigger:
1368         misc_deregister(&rfkill_miscdev);
1369 error_misc:
1370         class_unregister(&rfkill_class);
1371 error_class:
1372         return error;
1373 }
1374 subsys_initcall(rfkill_init);
1375
1376 static void __exit rfkill_exit(void)
1377 {
1378 #ifdef CONFIG_RFKILL_INPUT
1379         rfkill_handler_exit();
1380 #endif
1381         rfkill_global_led_trigger_unregister();
1382         misc_deregister(&rfkill_miscdev);
1383         class_unregister(&rfkill_class);
1384 }
1385 module_exit(rfkill_exit);