linux/net/rfkill/core.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright (C) 2006 - 2007 Ivo van Doorn
   4 * Copyright (C) 2007 Dmitry Torokhov
   5 * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   6 */
   7
   8#include <linux/kernel.h>
   9#include <linux/module.h>
  10#include <linux/init.h>
  11#include <linux/workqueue.h>
  12#include <linux/capability.h>
  13#include <linux/list.h>
  14#include <linux/mutex.h>
  15#include <linux/rfkill.h>
  16#include <linux/sched.h>
  17#include <linux/spinlock.h>
  18#include <linux/device.h>
  19#include <linux/miscdevice.h>
  20#include <linux/wait.h>
  21#include <linux/poll.h>
  22#include <linux/fs.h>
  23#include <linux/slab.h>
  24
  25#include "rfkill.h"
  26
  27#define POLL_INTERVAL           (5 * HZ)
  28
  29#define RFKILL_BLOCK_HW         BIT(0)
  30#define RFKILL_BLOCK_SW         BIT(1)
  31#define RFKILL_BLOCK_SW_PREV    BIT(2)
  32#define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  33                                 RFKILL_BLOCK_SW |\
  34                                 RFKILL_BLOCK_SW_PREV)
  35#define RFKILL_BLOCK_SW_SETCALL BIT(31)
  36
  37struct rfkill {
  38        spinlock_t              lock;
  39
  40        enum rfkill_type        type;
  41
  42        unsigned long           state;
  43
  44        u32                     idx;
  45
  46        bool                    registered;
  47        bool                    persistent;
  48        bool                    polling_paused;
  49        bool                    suspended;
  50
  51        const struct rfkill_ops *ops;
  52        void                    *data;
  53
  54#ifdef CONFIG_RFKILL_LEDS
  55        struct led_trigger      led_trigger;
  56        const char              *ledtrigname;
  57#endif
  58
  59        struct device           dev;
  60        struct list_head        node;
  61
  62        struct delayed_work     poll_work;
  63        struct work_struct      uevent_work;
  64        struct work_struct      sync_work;
  65        char                    name[];
  66};
  67#define to_rfkill(d)    container_of(d, struct rfkill, dev)
  68
  69struct rfkill_int_event {
  70        struct list_head        list;
  71        struct rfkill_event     ev;
  72};
  73
  74struct rfkill_data {
  75        struct list_head        list;
  76        struct list_head        events;
  77        struct mutex            mtx;
  78        wait_queue_head_t       read_wait;
  79        bool                    input_handler;
  80};
  81
  82
  83MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  84MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  85MODULE_DESCRIPTION("RF switch support");
  86MODULE_LICENSE("GPL");
  87
  88
  89/*
  90 * The locking here should be made much smarter, we currently have
  91 * a bit of a stupid situation because drivers might want to register
  92 * the rfkill struct under their own lock, and take this lock during
  93 * rfkill method calls -- which will cause an AB-BA deadlock situation.
  94 *
  95 * To fix that, we need to rework this code here to be mostly lock-free
  96 * and only use the mutex for list manipulations, not to protect the
  97 * various other global variables. Then we can avoid holding the mutex
  98 * around driver operations, and all is happy.
  99 */
 100static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 101static DEFINE_MUTEX(rfkill_global_mutex);
 102static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 103
 104static unsigned int rfkill_default_state = 1;
 105module_param_named(default_state, rfkill_default_state, uint, 0444);
 106MODULE_PARM_DESC(default_state,
 107                 "Default initial state for all radio types, 0 = radio off");
 108
 109static struct {
 110        bool cur, sav;
 111} rfkill_global_states[NUM_RFKILL_TYPES];
 112
 113static bool rfkill_epo_lock_active;
 114
 115
 116#ifdef CONFIG_RFKILL_LEDS
 117static void rfkill_led_trigger_event(struct rfkill *rfkill)
 118{
 119        struct led_trigger *trigger;
 120
 121        if (!rfkill->registered)
 122                return;
 123
 124        trigger = &rfkill->led_trigger;
 125
 126        if (rfkill->state & RFKILL_BLOCK_ANY)
 127                led_trigger_event(trigger, LED_OFF);
 128        else
 129                led_trigger_event(trigger, LED_FULL);
 130}
 131
 132static int rfkill_led_trigger_activate(struct led_classdev *led)
 133{
 134        struct rfkill *rfkill;
 135
 136        rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 137
 138        rfkill_led_trigger_event(rfkill);
 139
 140        return 0;
 141}
 142
 143const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 144{
 145        return rfkill->led_trigger.name;
 146}
 147EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 148
 149void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 150{
 151        BUG_ON(!rfkill);
 152
 153        rfkill->ledtrigname = name;
 154}
 155EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 156
 157static int rfkill_led_trigger_register(struct rfkill *rfkill)
 158{
 159        rfkill->led_trigger.name = rfkill->ledtrigname
 160                                        ? : dev_name(&rfkill->dev);
 161        rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 162        return led_trigger_register(&rfkill->led_trigger);
 163}
 164
 165static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 166{
 167        led_trigger_unregister(&rfkill->led_trigger);
 168}
 169
 170static struct led_trigger rfkill_any_led_trigger;
 171static struct led_trigger rfkill_none_led_trigger;
 172static struct work_struct rfkill_global_led_trigger_work;
 173
 174static void rfkill_global_led_trigger_worker(struct work_struct *work)
 175{
 176        enum led_brightness brightness = LED_OFF;
 177        struct rfkill *rfkill;
 178
 179        mutex_lock(&rfkill_global_mutex);
 180        list_for_each_entry(rfkill, &rfkill_list, node) {
 181                if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
 182                        brightness = LED_FULL;
 183                        break;
 184                }
 185        }
 186        mutex_unlock(&rfkill_global_mutex);
 187
 188        led_trigger_event(&rfkill_any_led_trigger, brightness);
 189        led_trigger_event(&rfkill_none_led_trigger,
 190                          brightness == LED_OFF ? LED_FULL : LED_OFF);
 191}
 192
 193static void rfkill_global_led_trigger_event(void)
 194{
 195        schedule_work(&rfkill_global_led_trigger_work);
 196}
 197
 198static int rfkill_global_led_trigger_register(void)
 199{
 200        int ret;
 201
 202        INIT_WORK(&rfkill_global_led_trigger_work,
 203                        rfkill_global_led_trigger_worker);
 204
 205        rfkill_any_led_trigger.name = "rfkill-any";
 206        ret = led_trigger_register(&rfkill_any_led_trigger);
 207        if (ret)
 208                return ret;
 209
 210        rfkill_none_led_trigger.name = "rfkill-none";
 211        ret = led_trigger_register(&rfkill_none_led_trigger);
 212        if (ret)
 213                led_trigger_unregister(&rfkill_any_led_trigger);
 214        else
 215                /* Delay activation until all global triggers are registered */
 216                rfkill_global_led_trigger_event();
 217
 218        return ret;
 219}
 220
 221static void rfkill_global_led_trigger_unregister(void)
 222{
 223        led_trigger_unregister(&rfkill_none_led_trigger);
 224        led_trigger_unregister(&rfkill_any_led_trigger);
 225        cancel_work_sync(&rfkill_global_led_trigger_work);
 226}
 227#else
 228static void rfkill_led_trigger_event(struct rfkill *rfkill)
 229{
 230}
 231
 232static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 233{
 234        return 0;
 235}
 236
 237static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 238{
 239}
 240
 241static void rfkill_global_led_trigger_event(void)
 242{
 243}
 244
 245static int rfkill_global_led_trigger_register(void)
 246{
 247        return 0;
 248}
 249
 250static void rfkill_global_led_trigger_unregister(void)
 251{
 252}
 253#endif /* CONFIG_RFKILL_LEDS */
 254
 255static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 256                              enum rfkill_operation op)
 257{
 258        unsigned long flags;
 259
 260        ev->idx = rfkill->idx;
 261        ev->type = rfkill->type;
 262        ev->op = op;
 263
 264        spin_lock_irqsave(&rfkill->lock, flags);
 265        ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 266        ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 267                                        RFKILL_BLOCK_SW_PREV));
 268        spin_unlock_irqrestore(&rfkill->lock, flags);
 269}
 270
 271static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 272{
 273        struct rfkill_data *data;
 274        struct rfkill_int_event *ev;
 275
 276        list_for_each_entry(data, &rfkill_fds, list) {
 277                ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 278                if (!ev)
 279                        continue;
 280                rfkill_fill_event(&ev->ev, rfkill, op);
 281                mutex_lock(&data->mtx);
 282                list_add_tail(&ev->list, &data->events);
 283                mutex_unlock(&data->mtx);
 284                wake_up_interruptible(&data->read_wait);
 285        }
 286}
 287
 288static void rfkill_event(struct rfkill *rfkill)
 289{
 290        if (!rfkill->registered)
 291                return;
 292
 293        kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 294
 295        /* also send event to /dev/rfkill */
 296        rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 297}
 298
 299/**
 300 * rfkill_set_block - wrapper for set_block method
 301 *
 302 * @rfkill: the rfkill struct to use
 303 * @blocked: the new software state
 304 *
 305 * Calls the set_block method (when applicable) and handles notifications
 306 * etc. as well.
 307 */
 308static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 309{
 310        unsigned long flags;
 311        bool prev, curr;
 312        int err;
 313
 314        if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 315                return;
 316
 317        /*
 318         * Some platforms (...!) generate input events which affect the
 319         * _hard_ kill state -- whenever something tries to change the
 320         * current software state query the hardware state too.
 321         */
 322        if (rfkill->ops->query)
 323                rfkill->ops->query(rfkill, rfkill->data);
 324
 325        spin_lock_irqsave(&rfkill->lock, flags);
 326        prev = rfkill->state & RFKILL_BLOCK_SW;
 327
 328        if (prev)
 329                rfkill->state |= RFKILL_BLOCK_SW_PREV;
 330        else
 331                rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 332
 333        if (blocked)
 334                rfkill->state |= RFKILL_BLOCK_SW;
 335        else
 336                rfkill->state &= ~RFKILL_BLOCK_SW;
 337
 338        rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 339        spin_unlock_irqrestore(&rfkill->lock, flags);
 340
 341        err = rfkill->ops->set_block(rfkill->data, blocked);
 342
 343        spin_lock_irqsave(&rfkill->lock, flags);
 344        if (err) {
 345                /*
 346                 * Failed -- reset status to _PREV, which may be different
 347                 * from what we have set _PREV to earlier in this function
 348                 * if rfkill_set_sw_state was invoked.
 349                 */
 350                if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 351                        rfkill->state |= RFKILL_BLOCK_SW;
 352                else
 353                        rfkill->state &= ~RFKILL_BLOCK_SW;
 354        }
 355        rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 356        rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 357        curr = rfkill->state & RFKILL_BLOCK_SW;
 358        spin_unlock_irqrestore(&rfkill->lock, flags);
 359
 360        rfkill_led_trigger_event(rfkill);
 361        rfkill_global_led_trigger_event();
 362
 363        if (prev != curr)
 364                rfkill_event(rfkill);
 365}
 366
 367static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
 368{
 369        int i;
 370
 371        if (type != RFKILL_TYPE_ALL) {
 372                rfkill_global_states[type].cur = blocked;
 373                return;
 374        }
 375
 376        for (i = 0; i < NUM_RFKILL_TYPES; i++)
 377                rfkill_global_states[i].cur = blocked;
 378}
 379
 380#ifdef CONFIG_RFKILL_INPUT
 381static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 382
 383/**
 384 * __rfkill_switch_all - Toggle state of all switches of given type
 385 * @type: type of interfaces to be affected
 386 * @blocked: the new state
 387 *
 388 * This function sets the state of all switches of given type,
 389 * unless a specific switch is suspended.
 390 *
 391 * Caller must have acquired rfkill_global_mutex.
 392 */
 393static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 394{
 395        struct rfkill *rfkill;
 396
 397        rfkill_update_global_state(type, blocked);
 398        list_for_each_entry(rfkill, &rfkill_list, node) {
 399                if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 400                        continue;
 401
 402                rfkill_set_block(rfkill, blocked);
 403        }
 404}
 405
 406/**
 407 * rfkill_switch_all - Toggle state of all switches of given type
 408 * @type: type of interfaces to be affected
 409 * @blocked: the new state
 410 *
 411 * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 412 * Please refer to __rfkill_switch_all() for details.
 413 *
 414 * Does nothing if the EPO lock is active.
 415 */
 416void rfkill_switch_all(enum rfkill_type type, bool blocked)
 417{
 418        if (atomic_read(&rfkill_input_disabled))
 419                return;
 420
 421        mutex_lock(&rfkill_global_mutex);
 422
 423        if (!rfkill_epo_lock_active)
 424                __rfkill_switch_all(type, blocked);
 425
 426        mutex_unlock(&rfkill_global_mutex);
 427}
 428
 429/**
 430 * rfkill_epo - emergency power off all transmitters
 431 *
 432 * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 433 * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 434 *
 435 * The global state before the EPO is saved and can be restored later
 436 * using rfkill_restore_states().
 437 */
 438void rfkill_epo(void)
 439{
 440        struct rfkill *rfkill;
 441        int i;
 442
 443        if (atomic_read(&rfkill_input_disabled))
 444                return;
 445
 446        mutex_lock(&rfkill_global_mutex);
 447
 448        rfkill_epo_lock_active = true;
 449        list_for_each_entry(rfkill, &rfkill_list, node)
 450                rfkill_set_block(rfkill, true);
 451
 452        for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 453                rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 454                rfkill_global_states[i].cur = true;
 455        }
 456
 457        mutex_unlock(&rfkill_global_mutex);
 458}
 459
 460/**
 461 * rfkill_restore_states - restore global states
 462 *
 463 * Restore (and sync switches to) the global state from the
 464 * states in rfkill_default_states.  This can undo the effects of
 465 * a call to rfkill_epo().
 466 */
 467void rfkill_restore_states(void)
 468{
 469        int i;
 470
 471        if (atomic_read(&rfkill_input_disabled))
 472                return;
 473
 474        mutex_lock(&rfkill_global_mutex);
 475
 476        rfkill_epo_lock_active = false;
 477        for (i = 0; i < NUM_RFKILL_TYPES; i++)
 478                __rfkill_switch_all(i, rfkill_global_states[i].sav);
 479        mutex_unlock(&rfkill_global_mutex);
 480}
 481
 482/**
 483 * rfkill_remove_epo_lock - unlock state changes
 484 *
 485 * Used by rfkill-input manually unlock state changes, when
 486 * the EPO switch is deactivated.
 487 */
 488void rfkill_remove_epo_lock(void)
 489{
 490        if (atomic_read(&rfkill_input_disabled))
 491                return;
 492
 493        mutex_lock(&rfkill_global_mutex);
 494        rfkill_epo_lock_active = false;
 495        mutex_unlock(&rfkill_global_mutex);
 496}
 497
 498/**
 499 * rfkill_is_epo_lock_active - returns true EPO is active
 500 *
 501 * Returns 0 (false) if there is NOT an active EPO condition,
 502 * and 1 (true) if there is an active EPO condition, which
 503 * locks all radios in one of the BLOCKED states.
 504 *
 505 * Can be called in atomic context.
 506 */
 507bool rfkill_is_epo_lock_active(void)
 508{
 509        return rfkill_epo_lock_active;
 510}
 511
 512/**
 513 * rfkill_get_global_sw_state - returns global state for a type
 514 * @type: the type to get the global state of
 515 *
 516 * Returns the current global state for a given wireless
 517 * device type.
 518 */
 519bool rfkill_get_global_sw_state(const enum rfkill_type type)
 520{
 521        return rfkill_global_states[type].cur;
 522}
 523#endif
 524
 525bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 526{
 527        unsigned long flags;
 528        bool ret, prev;
 529
 530        BUG_ON(!rfkill);
 531
 532        spin_lock_irqsave(&rfkill->lock, flags);
 533        prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 534        if (blocked)
 535                rfkill->state |= RFKILL_BLOCK_HW;
 536        else
 537                rfkill->state &= ~RFKILL_BLOCK_HW;
 538        ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
 539        spin_unlock_irqrestore(&rfkill->lock, flags);
 540
 541        rfkill_led_trigger_event(rfkill);
 542        rfkill_global_led_trigger_event();
 543
 544        if (rfkill->registered && prev != blocked)
 545                schedule_work(&rfkill->uevent_work);
 546
 547        return ret;
 548}
 549EXPORT_SYMBOL(rfkill_set_hw_state);
 550
 551static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 552{
 553        u32 bit = RFKILL_BLOCK_SW;
 554
 555        /* if in a ops->set_block right now, use other bit */
 556        if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 557                bit = RFKILL_BLOCK_SW_PREV;
 558
 559        if (blocked)
 560                rfkill->state |= bit;
 561        else
 562                rfkill->state &= ~bit;
 563}
 564
 565bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 566{
 567        unsigned long flags;
 568        bool prev, hwblock;
 569
 570        BUG_ON(!rfkill);
 571
 572        spin_lock_irqsave(&rfkill->lock, flags);
 573        prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 574        __rfkill_set_sw_state(rfkill, blocked);
 575        hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 576        blocked = blocked || hwblock;
 577        spin_unlock_irqrestore(&rfkill->lock, flags);
 578
 579        if (!rfkill->registered)
 580                return blocked;
 581
 582        if (prev != blocked && !hwblock)
 583                schedule_work(&rfkill->uevent_work);
 584
 585        rfkill_led_trigger_event(rfkill);
 586        rfkill_global_led_trigger_event();
 587
 588        return blocked;
 589}
 590EXPORT_SYMBOL(rfkill_set_sw_state);
 591
 592void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 593{
 594        unsigned long flags;
 595
 596        BUG_ON(!rfkill);
 597        BUG_ON(rfkill->registered);
 598
 599        spin_lock_irqsave(&rfkill->lock, flags);
 600        __rfkill_set_sw_state(rfkill, blocked);
 601        rfkill->persistent = true;
 602        spin_unlock_irqrestore(&rfkill->lock, flags);
 603}
 604EXPORT_SYMBOL(rfkill_init_sw_state);
 605
 606void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 607{
 608        unsigned long flags;
 609        bool swprev, hwprev;
 610
 611        BUG_ON(!rfkill);
 612
 613        spin_lock_irqsave(&rfkill->lock, flags);
 614
 615        /*
 616         * No need to care about prev/setblock ... this is for uevent only
 617         * and that will get triggered by rfkill_set_block anyway.
 618         */
 619        swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 620        hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 621        __rfkill_set_sw_state(rfkill, sw);
 622        if (hw)
 623                rfkill->state |= RFKILL_BLOCK_HW;
 624        else
 625                rfkill->state &= ~RFKILL_BLOCK_HW;
 626
 627        spin_unlock_irqrestore(&rfkill->lock, flags);
 628
 629        if (!rfkill->registered) {
 630                rfkill->persistent = true;
 631        } else {
 632                if (swprev != sw || hwprev != hw)
 633                        schedule_work(&rfkill->uevent_work);
 634
 635                rfkill_led_trigger_event(rfkill);
 636                rfkill_global_led_trigger_event();
 637        }
 638}
 639EXPORT_SYMBOL(rfkill_set_states);
 640
 641static const char * const rfkill_types[] = {
 642        NULL, /* RFKILL_TYPE_ALL */
 643        "wlan",
 644        "bluetooth",
 645        "ultrawideband",
 646        "wimax",
 647        "wwan",
 648        "gps",
 649        "fm",
 650        "nfc",
 651};
 652
 653enum rfkill_type rfkill_find_type(const char *name)
 654{
 655        int i;
 656
 657        BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
 658
 659        if (!name)
 660                return RFKILL_TYPE_ALL;
 661
 662        for (i = 1; i < NUM_RFKILL_TYPES; i++)
 663                if (!strcmp(name, rfkill_types[i]))
 664                        return i;
 665        return RFKILL_TYPE_ALL;
 666}
 667EXPORT_SYMBOL(rfkill_find_type);
 668
 669static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 670                         char *buf)
 671{
 672        struct rfkill *rfkill = to_rfkill(dev);
 673
 674        return sprintf(buf, "%s\n", rfkill->name);
 675}
 676static DEVICE_ATTR_RO(name);
 677
 678static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 679                         char *buf)
 680{
 681        struct rfkill *rfkill = to_rfkill(dev);
 682
 683        return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
 684}
 685static DEVICE_ATTR_RO(type);
 686
 687static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 688                          char *buf)
 689{
 690        struct rfkill *rfkill = to_rfkill(dev);
 691
 692        return sprintf(buf, "%d\n", rfkill->idx);
 693}
 694static DEVICE_ATTR_RO(index);
 695
 696static ssize_t persistent_show(struct device *dev,
 697                               struct device_attribute *attr, char *buf)
 698{
 699        struct rfkill *rfkill = to_rfkill(dev);
 700
 701        return sprintf(buf, "%d\n", rfkill->persistent);
 702}
 703static DEVICE_ATTR_RO(persistent);
 704
 705static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 706                         char *buf)
 707{
 708        struct rfkill *rfkill = to_rfkill(dev);
 709
 710        return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 711}
 712static DEVICE_ATTR_RO(hard);
 713
 714static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 715                         char *buf)
 716{
 717        struct rfkill *rfkill = to_rfkill(dev);
 718
 719        return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 720}
 721
 722static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 723                          const char *buf, size_t count)
 724{
 725        struct rfkill *rfkill = to_rfkill(dev);
 726        unsigned long state;
 727        int err;
 728
 729        if (!capable(CAP_NET_ADMIN))
 730                return -EPERM;
 731
 732        err = kstrtoul(buf, 0, &state);
 733        if (err)
 734                return err;
 735
 736        if (state > 1 )
 737                return -EINVAL;
 738
 739        mutex_lock(&rfkill_global_mutex);
 740        rfkill_set_block(rfkill, state);
 741        mutex_unlock(&rfkill_global_mutex);
 742
 743        return count;
 744}
 745static DEVICE_ATTR_RW(soft);
 746
 747static u8 user_state_from_blocked(unsigned long state)
 748{
 749        if (state & RFKILL_BLOCK_HW)
 750                return RFKILL_USER_STATE_HARD_BLOCKED;
 751        if (state & RFKILL_BLOCK_SW)
 752                return RFKILL_USER_STATE_SOFT_BLOCKED;
 753
 754        return RFKILL_USER_STATE_UNBLOCKED;
 755}
 756
 757static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 758                          char *buf)
 759{
 760        struct rfkill *rfkill = to_rfkill(dev);
 761
 762        return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 763}
 764
 765static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 766                           const char *buf, size_t count)
 767{
 768        struct rfkill *rfkill = to_rfkill(dev);
 769        unsigned long state;
 770        int err;
 771
 772        if (!capable(CAP_NET_ADMIN))
 773                return -EPERM;
 774
 775        err = kstrtoul(buf, 0, &state);
 776        if (err)
 777                return err;
 778
 779        if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 780            state != RFKILL_USER_STATE_UNBLOCKED)
 781                return -EINVAL;
 782
 783        mutex_lock(&rfkill_global_mutex);
 784        rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 785        mutex_unlock(&rfkill_global_mutex);
 786
 787        return count;
 788}
 789static DEVICE_ATTR_RW(state);
 790
 791static struct attribute *rfkill_dev_attrs[] = {
 792        &dev_attr_name.attr,
 793        &dev_attr_type.attr,
 794        &dev_attr_index.attr,
 795        &dev_attr_persistent.attr,
 796        &dev_attr_state.attr,
 797        &dev_attr_soft.attr,
 798        &dev_attr_hard.attr,
 799        NULL,
 800};
 801ATTRIBUTE_GROUPS(rfkill_dev);
 802
 803static void rfkill_release(struct device *dev)
 804{
 805        struct rfkill *rfkill = to_rfkill(dev);
 806
 807        kfree(rfkill);
 808}
 809
 810static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 811{
 812        struct rfkill *rfkill = to_rfkill(dev);
 813        unsigned long flags;
 814        u32 state;
 815        int error;
 816
 817        error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 818        if (error)
 819                return error;
 820        error = add_uevent_var(env, "RFKILL_TYPE=%s",
 821                               rfkill_types[rfkill->type]);
 822        if (error)
 823                return error;
 824        spin_lock_irqsave(&rfkill->lock, flags);
 825        state = rfkill->state;
 826        spin_unlock_irqrestore(&rfkill->lock, flags);
 827        error = add_uevent_var(env, "RFKILL_STATE=%d",
 828                               user_state_from_blocked(state));
 829        return error;
 830}
 831
 832void rfkill_pause_polling(struct rfkill *rfkill)
 833{
 834        BUG_ON(!rfkill);
 835
 836        if (!rfkill->ops->poll)
 837                return;
 838
 839        rfkill->polling_paused = true;
 840        cancel_delayed_work_sync(&rfkill->poll_work);
 841}
 842EXPORT_SYMBOL(rfkill_pause_polling);
 843
 844void rfkill_resume_polling(struct rfkill *rfkill)
 845{
 846        BUG_ON(!rfkill);
 847
 848        if (!rfkill->ops->poll)
 849                return;
 850
 851        rfkill->polling_paused = false;
 852
 853        if (rfkill->suspended)
 854                return;
 855
 856        queue_delayed_work(system_power_efficient_wq,
 857                           &rfkill->poll_work, 0);
 858}
 859EXPORT_SYMBOL(rfkill_resume_polling);
 860
 861#ifdef CONFIG_PM_SLEEP
 862static int rfkill_suspend(struct device *dev)
 863{
 864        struct rfkill *rfkill = to_rfkill(dev);
 865
 866        rfkill->suspended = true;
 867        cancel_delayed_work_sync(&rfkill->poll_work);
 868
 869        return 0;
 870}
 871
 872static int rfkill_resume(struct device *dev)
 873{
 874        struct rfkill *rfkill = to_rfkill(dev);
 875        bool cur;
 876
 877        rfkill->suspended = false;
 878
 879        if (!rfkill->persistent) {
 880                cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 881                rfkill_set_block(rfkill, cur);
 882        }
 883
 884        if (rfkill->ops->poll && !rfkill->polling_paused)
 885                queue_delayed_work(system_power_efficient_wq,
 886                                   &rfkill->poll_work, 0);
 887
 888        return 0;
 889}
 890
 891static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 892#define RFKILL_PM_OPS (&rfkill_pm_ops)
 893#else
 894#define RFKILL_PM_OPS NULL
 895#endif
 896
 897static struct class rfkill_class = {
 898        .name           = "rfkill",
 899        .dev_release    = rfkill_release,
 900        .dev_groups     = rfkill_dev_groups,
 901        .dev_uevent     = rfkill_dev_uevent,
 902        .pm             = RFKILL_PM_OPS,
 903};
 904
 905bool rfkill_blocked(struct rfkill *rfkill)
 906{
 907        unsigned long flags;
 908        u32 state;
 909
 910        spin_lock_irqsave(&rfkill->lock, flags);
 911        state = rfkill->state;
 912        spin_unlock_irqrestore(&rfkill->lock, flags);
 913
 914        return !!(state & RFKILL_BLOCK_ANY);
 915}
 916EXPORT_SYMBOL(rfkill_blocked);
 917
 918
 919struct rfkill * __must_check rfkill_alloc(const char *name,
 920                                          struct device *parent,
 921                                          const enum rfkill_type type,
 922                                          const struct rfkill_ops *ops,
 923                                          void *ops_data)
 924{
 925        struct rfkill *rfkill;
 926        struct device *dev;
 927
 928        if (WARN_ON(!ops))
 929                return NULL;
 930
 931        if (WARN_ON(!ops->set_block))
 932                return NULL;
 933
 934        if (WARN_ON(!name))
 935                return NULL;
 936
 937        if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 938                return NULL;
 939
 940        rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 941        if (!rfkill)
 942                return NULL;
 943
 944        spin_lock_init(&rfkill->lock);
 945        INIT_LIST_HEAD(&rfkill->node);
 946        rfkill->type = type;
 947        strcpy(rfkill->name, name);
 948        rfkill->ops = ops;
 949        rfkill->data = ops_data;
 950
 951        dev = &rfkill->dev;
 952        dev->class = &rfkill_class;
 953        dev->parent = parent;
 954        device_initialize(dev);
 955
 956        return rfkill;
 957}
 958EXPORT_SYMBOL(rfkill_alloc);
 959
 960static void rfkill_poll(struct work_struct *work)
 961{
 962        struct rfkill *rfkill;
 963
 964        rfkill = container_of(work, struct rfkill, poll_work.work);
 965
 966        /*
 967         * Poll hardware state -- driver will use one of the
 968         * rfkill_set{,_hw,_sw}_state functions and use its
 969         * return value to update the current status.
 970         */
 971        rfkill->ops->poll(rfkill, rfkill->data);
 972
 973        queue_delayed_work(system_power_efficient_wq,
 974                &rfkill->poll_work,
 975                round_jiffies_relative(POLL_INTERVAL));
 976}
 977
 978static void rfkill_uevent_work(struct work_struct *work)
 979{
 980        struct rfkill *rfkill;
 981
 982        rfkill = container_of(work, struct rfkill, uevent_work);
 983
 984        mutex_lock(&rfkill_global_mutex);
 985        rfkill_event(rfkill);
 986        mutex_unlock(&rfkill_global_mutex);
 987}
 988
 989static void rfkill_sync_work(struct work_struct *work)
 990{
 991        struct rfkill *rfkill;
 992        bool cur;
 993
 994        rfkill = container_of(work, struct rfkill, sync_work);
 995
 996        mutex_lock(&rfkill_global_mutex);
 997        cur = rfkill_global_states[rfkill->type].cur;
 998        rfkill_set_block(rfkill, cur);
 999        mutex_unlock(&rfkill_global_mutex);
1000}
1001
1002int __must_check rfkill_register(struct rfkill *rfkill)
1003{
1004        static unsigned long rfkill_no;
1005        struct device *dev;
1006        int error;
1007
1008        if (!rfkill)
1009                return -EINVAL;
1010
1011        dev = &rfkill->dev;
1012
1013        mutex_lock(&rfkill_global_mutex);
1014
1015        if (rfkill->registered) {
1016                error = -EALREADY;
1017                goto unlock;
1018        }
1019
1020        rfkill->idx = rfkill_no;
1021        dev_set_name(dev, "rfkill%lu", rfkill_no);
1022        rfkill_no++;
1023
1024        list_add_tail(&rfkill->node, &rfkill_list);
1025
1026        error = device_add(dev);
1027        if (error)
1028                goto remove;
1029
1030        error = rfkill_led_trigger_register(rfkill);
1031        if (error)
1032                goto devdel;
1033
1034        rfkill->registered = true;
1035
1036        INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
1037        INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
1038        INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
1039
1040        if (rfkill->ops->poll)
1041                queue_delayed_work(system_power_efficient_wq,
1042                        &rfkill->poll_work,
1043                        round_jiffies_relative(POLL_INTERVAL));
1044
1045        if (!rfkill->persistent || rfkill_epo_lock_active) {
1046                schedule_work(&rfkill->sync_work);
1047        } else {
1048#ifdef CONFIG_RFKILL_INPUT
1049                bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
1050
1051                if (!atomic_read(&rfkill_input_disabled))
1052                        __rfkill_switch_all(rfkill->type, soft_blocked);
1053#endif
1054        }
1055
1056        rfkill_global_led_trigger_event();
1057        rfkill_send_events(rfkill, RFKILL_OP_ADD);
1058
1059        mutex_unlock(&rfkill_global_mutex);
1060        return 0;
1061
1062 devdel:
1063        device_del(&rfkill->dev);
1064 remove:
1065        list_del_init(&rfkill->node);
1066 unlock:
1067        mutex_unlock(&rfkill_global_mutex);
1068        return error;
1069}
1070EXPORT_SYMBOL(rfkill_register);
1071
1072void rfkill_unregister(struct rfkill *rfkill)
1073{
1074        BUG_ON(!rfkill);
1075
1076        if (rfkill->ops->poll)
1077                cancel_delayed_work_sync(&rfkill->poll_work);
1078
1079        cancel_work_sync(&rfkill->uevent_work);
1080        cancel_work_sync(&rfkill->sync_work);
1081
1082        rfkill->registered = false;
1083
1084        device_del(&rfkill->dev);
1085
1086        mutex_lock(&rfkill_global_mutex);
1087        rfkill_send_events(rfkill, RFKILL_OP_DEL);
1088        list_del_init(&rfkill->node);
1089        rfkill_global_led_trigger_event();
1090        mutex_unlock(&rfkill_global_mutex);
1091
1092        rfkill_led_trigger_unregister(rfkill);
1093}
1094EXPORT_SYMBOL(rfkill_unregister);
1095
1096void rfkill_destroy(struct rfkill *rfkill)
1097{
1098        if (rfkill)
1099                put_device(&rfkill->dev);
1100}
1101EXPORT_SYMBOL(rfkill_destroy);
1102
1103static int rfkill_fop_open(struct inode *inode, struct file *file)
1104{
1105        struct rfkill_data *data;
1106        struct rfkill *rfkill;
1107        struct rfkill_int_event *ev, *tmp;
1108
1109        data = kzalloc(sizeof(*data), GFP_KERNEL);
1110        if (!data)
1111                return -ENOMEM;
1112
1113        INIT_LIST_HEAD(&data->events);
1114        mutex_init(&data->mtx);
1115        init_waitqueue_head(&data->read_wait);
1116
1117        mutex_lock(&rfkill_global_mutex);
1118        mutex_lock(&data->mtx);
1119        /*
1120         * start getting events from elsewhere but hold mtx to get
1121         * startup events added first
1122         */
1123
1124        list_for_each_entry(rfkill, &rfkill_list, node) {
1125                ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1126                if (!ev)
1127                        goto free;
1128                rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1129                list_add_tail(&ev->list, &data->events);
1130        }
1131        list_add(&data->list, &rfkill_fds);
1132        mutex_unlock(&data->mtx);
1133        mutex_unlock(&rfkill_global_mutex);
1134
1135        file->private_data = data;
1136
1137        return stream_open(inode, file);
1138
1139 free:
1140        mutex_unlock(&data->mtx);
1141        mutex_unlock(&rfkill_global_mutex);
1142        mutex_destroy(&data->mtx);
1143        list_for_each_entry_safe(ev, tmp, &data->events, list)
1144                kfree(ev);
1145        kfree(data);
1146        return -ENOMEM;
1147}
1148
1149static __poll_t rfkill_fop_poll(struct file *file, poll_table *wait)
1150{
1151        struct rfkill_data *data = file->private_data;
1152        __poll_t res = EPOLLOUT | EPOLLWRNORM;
1153
1154        poll_wait(file, &data->read_wait, wait);
1155
1156        mutex_lock(&data->mtx);
1157        if (!list_empty(&data->events))
1158                res = EPOLLIN | EPOLLRDNORM;
1159        mutex_unlock(&data->mtx);
1160
1161        return res;
1162}
1163
1164static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1165                               size_t count, loff_t *pos)
1166{
1167        struct rfkill_data *data = file->private_data;
1168        struct rfkill_int_event *ev;
1169        unsigned long sz;
1170        int ret;
1171
1172        mutex_lock(&data->mtx);
1173
1174        while (list_empty(&data->events)) {
1175                if (file->f_flags & O_NONBLOCK) {
1176                        ret = -EAGAIN;
1177                        goto out;
1178                }
1179                mutex_unlock(&data->mtx);
1180                /* since we re-check and it just compares pointers,
1181                 * using !list_empty() without locking isn't a problem
1182                 */
1183                ret = wait_event_interruptible(data->read_wait,
1184                                               !list_empty(&data->events));
1185                mutex_lock(&data->mtx);
1186
1187                if (ret)
1188                        goto out;
1189        }
1190
1191        ev = list_first_entry(&data->events, struct rfkill_int_event,
1192                                list);
1193
1194        sz = min_t(unsigned long, sizeof(ev->ev), count);
1195        ret = sz;
1196        if (copy_to_user(buf, &ev->ev, sz))
1197                ret = -EFAULT;
1198
1199        list_del(&ev->list);
1200        kfree(ev);
1201 out:
1202        mutex_unlock(&data->mtx);
1203        return ret;
1204}
1205
1206static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1207                                size_t count, loff_t *pos)
1208{
1209        struct rfkill *rfkill;
1210        struct rfkill_event ev;
1211        int ret;
1212
1213        /* we don't need the 'hard' variable but accept it */
1214        if (count < RFKILL_EVENT_SIZE_V1 - 1)
1215                return -EINVAL;
1216
1217        /*
1218         * Copy as much data as we can accept into our 'ev' buffer,
1219         * but tell userspace how much we've copied so it can determine
1220         * our API version even in a write() call, if it cares.
1221         */
1222        count = min(count, sizeof(ev));
1223        if (copy_from_user(&ev, buf, count))
1224                return -EFAULT;
1225
1226        if (ev.type >= NUM_RFKILL_TYPES)
1227                return -EINVAL;
1228
1229        mutex_lock(&rfkill_global_mutex);
1230
1231        switch (ev.op) {
1232        case RFKILL_OP_CHANGE_ALL:
1233                rfkill_update_global_state(ev.type, ev.soft);
1234                list_for_each_entry(rfkill, &rfkill_list, node)
1235                        if (rfkill->type == ev.type ||
1236                            ev.type == RFKILL_TYPE_ALL)
1237                                rfkill_set_block(rfkill, ev.soft);
1238                ret = 0;
1239                break;
1240        case RFKILL_OP_CHANGE:
1241                list_for_each_entry(rfkill, &rfkill_list, node)
1242                        if (rfkill->idx == ev.idx &&
1243                            (rfkill->type == ev.type ||
1244                             ev.type == RFKILL_TYPE_ALL))
1245                                rfkill_set_block(rfkill, ev.soft);
1246                ret = 0;
1247                break;
1248        default:
1249                ret = -EINVAL;
1250                break;
1251        }
1252
1253        mutex_unlock(&rfkill_global_mutex);
1254
1255        return ret ?: count;
1256}
1257
1258static int rfkill_fop_release(struct inode *inode, struct file *file)
1259{
1260        struct rfkill_data *data = file->private_data;
1261        struct rfkill_int_event *ev, *tmp;
1262
1263        mutex_lock(&rfkill_global_mutex);
1264        list_del(&data->list);
1265        mutex_unlock(&rfkill_global_mutex);
1266
1267        mutex_destroy(&data->mtx);
1268        list_for_each_entry_safe(ev, tmp, &data->events, list)
1269                kfree(ev);
1270
1271#ifdef CONFIG_RFKILL_INPUT
1272        if (data->input_handler)
1273                if (atomic_dec_return(&rfkill_input_disabled) == 0)
1274                        printk(KERN_DEBUG "rfkill: input handler enabled\n");
1275#endif
1276
1277        kfree(data);
1278
1279        return 0;
1280}
1281
1282#ifdef CONFIG_RFKILL_INPUT
1283static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1284                             unsigned long arg)
1285{
1286        struct rfkill_data *data = file->private_data;
1287
1288        if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1289                return -ENOSYS;
1290
1291        if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1292                return -ENOSYS;
1293
1294        mutex_lock(&data->mtx);
1295
1296        if (!data->input_handler) {
1297                if (atomic_inc_return(&rfkill_input_disabled) == 1)
1298                        printk(KERN_DEBUG "rfkill: input handler disabled\n");
1299                data->input_handler = true;
1300        }
1301
1302        mutex_unlock(&data->mtx);
1303
1304        return 0;
1305}
1306#endif
1307
1308static const struct file_operations rfkill_fops = {
1309        .owner          = THIS_MODULE,
1310        .open           = rfkill_fop_open,
1311        .read           = rfkill_fop_read,
1312        .write          = rfkill_fop_write,
1313        .poll           = rfkill_fop_poll,
1314        .release        = rfkill_fop_release,
1315#ifdef CONFIG_RFKILL_INPUT
1316        .unlocked_ioctl = rfkill_fop_ioctl,
1317        .compat_ioctl   = compat_ptr_ioctl,
1318#endif
1319        .llseek         = no_llseek,
1320};
1321
1322#define RFKILL_NAME "rfkill"
1323
1324static struct miscdevice rfkill_miscdev = {
1325        .fops   = &rfkill_fops,
1326        .name   = RFKILL_NAME,
1327        .minor  = RFKILL_MINOR,
1328};
1329
1330static int __init rfkill_init(void)
1331{
1332        int error;
1333
1334        rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1335
1336        error = class_register(&rfkill_class);
1337        if (error)
1338                goto error_class;
1339
1340        error = misc_register(&rfkill_miscdev);
1341        if (error)
1342                goto error_misc;
1343
1344        error = rfkill_global_led_trigger_register();
1345        if (error)
1346                goto error_led_trigger;
1347
1348#ifdef CONFIG_RFKILL_INPUT
1349        error = rfkill_handler_init();
1350        if (error)
1351                goto error_input;
1352#endif
1353
1354        return 0;
1355
1356#ifdef CONFIG_RFKILL_INPUT
1357error_input:
1358        rfkill_global_led_trigger_unregister();
1359#endif
1360error_led_trigger:
1361        misc_deregister(&rfkill_miscdev);
1362error_misc:
1363        class_unregister(&rfkill_class);
1364error_class:
1365        return error;
1366}
1367subsys_initcall(rfkill_init);
1368
1369static void __exit rfkill_exit(void)
1370{
1371#ifdef CONFIG_RFKILL_INPUT
1372        rfkill_handler_exit();
1373#endif
1374        rfkill_global_led_trigger_unregister();
1375        misc_deregister(&rfkill_miscdev);
1376        class_unregister(&rfkill_class);
1377}
1378module_exit(rfkill_exit);
1379
1380MODULE_ALIAS_MISCDEV(RFKILL_MINOR);
1381MODULE_ALIAS("devname:" RFKILL_NAME);
1382