net/rfkill/core.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/capability.h>
  25 #include <linux/list.h>
  26 #include <linux/mutex.h>
  27 #include <linux/rfkill.h>
  28 #include <linux/sched.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/device.h>
  31 #include <linux/miscdevice.h>
  32 #include <linux/wait.h>
  33 #include <linux/poll.h>
  34 #include <linux/fs.h>
  35 #include <linux/slab.h>
  36
  37 #include "rfkill.h"
  38
  39 #define POLL_INTERVAL           (5 * HZ)
  40
  41 #define RFKILL_BLOCK_HW         BIT(0)
  42 #define RFKILL_BLOCK_SW         BIT(1)
  43 #define RFKILL_BLOCK_SW_PREV    BIT(2)
  44 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
  45                                  RFKILL_BLOCK_SW |\
  46                                  RFKILL_BLOCK_SW_PREV)
  47 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
  48
  49 struct rfkill {
  50         spinlock_t              lock;
  51
  52         enum rfkill_type        type;
  53
  54         unsigned long           state;
  55
  56         u32                     idx;
  57
  58         bool                    registered;
  59         bool                    persistent;
  60         bool                    polling_paused;
  61         bool                    suspended;
  62
  63         const struct rfkill_ops *ops;
  64         void                    *data;
  65
  66 #ifdef CONFIG_RFKILL_LEDS
  67         struct led_trigger      led_trigger;
  68         const char              *ledtrigname;
  69 #endif
  70
  71         struct device           dev;
  72         struct list_head        node;
  73
  74         struct delayed_work     poll_work;
  75         struct work_struct      uevent_work;
  76         struct work_struct      sync_work;
  77         char                    name[];
  78 };
  79 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
  80
  81 struct rfkill_int_event {
  82         struct list_head        list;
  83         struct rfkill_event     ev;
  84 };
  85
  86 struct rfkill_data {
  87         struct list_head        list;
  88         struct list_head        events;
  89         struct mutex            mtx;
  90         wait_queue_head_t       read_wait;
  91         bool                    input_handler;
  92 };
  93
  94
  95 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  96 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  97 MODULE_DESCRIPTION("RF switch support");
  98 MODULE_LICENSE("GPL");
  99
 100
 101 /*
 102  * The locking here should be made much smarter, we currently have
 103  * a bit of a stupid situation because drivers might want to register
 104  * the rfkill struct under their own lock, and take this lock during
 105  * rfkill method calls -- which will cause an AB-BA deadlock situation.
 106  *
 107  * To fix that, we need to rework this code here to be mostly lock-free
 108  * and only use the mutex for list manipulations, not to protect the
 109  * various other global variables. Then we can avoid holding the mutex
 110  * around driver operations, and all is happy.
 111  */
 112 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
 113 static DEFINE_MUTEX(rfkill_global_mutex);
 114 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
 115
 116 static unsigned int rfkill_default_state = 1;
 117 module_param_named(default_state, rfkill_default_state, uint, 0444);
 118 MODULE_PARM_DESC(default_state,
 119                  "Default initial state for all radio types, 0 = radio off");
 120
 121 static struct {
 122         bool cur, sav;
 123 } rfkill_global_states[NUM_RFKILL_TYPES];
 124
 125 static bool rfkill_epo_lock_active;
 126
 127
 128 #ifdef CONFIG_RFKILL_LEDS
 129 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 130 {
 131         struct led_trigger *trigger;
 132
 133         if (!rfkill->registered)
 134                 return;
 135
 136         trigger = &rfkill->led_trigger;
 137
 138         if (rfkill->state & RFKILL_BLOCK_ANY)
 139                 led_trigger_event(trigger, LED_OFF);
 140         else
 141                 led_trigger_event(trigger, LED_FULL);
 142 }
 143
 144 static void rfkill_led_trigger_activate(struct led_classdev *led)
 145 {
 146         struct rfkill *rfkill;
 147
 148         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
 149
 150         rfkill_led_trigger_event(rfkill);
 151 }
 152
 153 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
 154 {
 155         return rfkill->led_trigger.name;
 156 }
 157 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
 158
 159 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
 160 {
 161         BUG_ON(!rfkill);
 162
 163         rfkill->ledtrigname = name;
 164 }
 165 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
 166
 167 static int rfkill_led_trigger_register(struct rfkill *rfkill)
 168 {
 169         rfkill->led_trigger.name = rfkill->ledtrigname
 170                                         ? : dev_name(&rfkill->dev);
 171         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
 172         return led_trigger_register(&rfkill->led_trigger);
 173 }
 174
 175 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 176 {
 177         led_trigger_unregister(&rfkill->led_trigger);
 178 }
 179 #else
 180 static void rfkill_led_trigger_event(struct rfkill *rfkill)
 181 {
 182 }
 183
 184 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
 185 {
 186         return 0;
 187 }
 188
 189 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 190 {
 191 }
 192 #endif /* CONFIG_RFKILL_LEDS */
 193
 194 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
 195                               enum rfkill_operation op)
 196 {
 197         unsigned long flags;
 198
 199         ev->idx = rfkill->idx;
 200         ev->type = rfkill->type;
 201         ev->op = op;
 202
 203         spin_lock_irqsave(&rfkill->lock, flags);
 204         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
 205         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
 206                                         RFKILL_BLOCK_SW_PREV));
 207         spin_unlock_irqrestore(&rfkill->lock, flags);
 208 }
 209
 210 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
 211 {
 212         struct rfkill_data *data;
 213         struct rfkill_int_event *ev;
 214
 215         list_for_each_entry(data, &rfkill_fds, list) {
 216                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 217                 if (!ev)
 218                         continue;
 219                 rfkill_fill_event(&ev->ev, rfkill, op);
 220                 mutex_lock(&data->mtx);
 221                 list_add_tail(&ev->list, &data->events);
 222                 mutex_unlock(&data->mtx);
 223                 wake_up_interruptible(&data->read_wait);
 224         }
 225 }
 226
 227 static void rfkill_event(struct rfkill *rfkill)
 228 {
 229         if (!rfkill->registered)
 230                 return;
 231
 232         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
 233
 234         /* also send event to /dev/rfkill */
 235         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
 236 }
 237
 238 /**
 239  * rfkill_set_block - wrapper for set_block method
 240  *
 241  * @rfkill: the rfkill struct to use
 242  * @blocked: the new software state
 243  *
 244  * Calls the set_block method (when applicable) and handles notifications
 245  * etc. as well.
 246  */
 247 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
 248 {
 249         unsigned long flags;
 250         bool prev, curr;
 251         int err;
 252
 253         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
 254                 return;
 255
 256         /*
 257          * Some platforms (...!) generate input events which affect the
 258          * _hard_ kill state -- whenever something tries to change the
 259          * current software state query the hardware state too.
 260          */
 261         if (rfkill->ops->query)
 262                 rfkill->ops->query(rfkill, rfkill->data);
 263
 264         spin_lock_irqsave(&rfkill->lock, flags);
 265         prev = rfkill->state & RFKILL_BLOCK_SW;
 266
 267         if (prev)
 268                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
 269         else
 270                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 271
 272         if (blocked)
 273                 rfkill->state |= RFKILL_BLOCK_SW;
 274         else
 275                 rfkill->state &= ~RFKILL_BLOCK_SW;
 276
 277         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
 278         spin_unlock_irqrestore(&rfkill->lock, flags);
 279
 280         err = rfkill->ops->set_block(rfkill->data, blocked);
 281
 282         spin_lock_irqsave(&rfkill->lock, flags);
 283         if (err) {
 284                 /*
 285                  * Failed -- reset status to _prev, this may be different
 286                  * from what set set _PREV to earlier in this function
 287                  * if rfkill_set_sw_state was invoked.
 288                  */
 289                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
 290                         rfkill->state |= RFKILL_BLOCK_SW;
 291                 else
 292                         rfkill->state &= ~RFKILL_BLOCK_SW;
 293         }
 294         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
 295         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
 296         curr = rfkill->state & RFKILL_BLOCK_SW;
 297         spin_unlock_irqrestore(&rfkill->lock, flags);
 298
 299         rfkill_led_trigger_event(rfkill);
 300
 301         if (prev != curr)
 302                 rfkill_event(rfkill);
 303 }
 304
 305 #ifdef CONFIG_RFKILL_INPUT
 306 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
 307
 308 /**
 309  * __rfkill_switch_all - Toggle state of all switches of given type
 310  * @type: type of interfaces to be affected
 311  * @blocked: the new state
 312  *
 313  * This function sets the state of all switches of given type,
 314  * unless a specific switch is suspended.
 315  *
 316  * Caller must have acquired rfkill_global_mutex.
 317  */
 318 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
 319 {
 320         struct rfkill *rfkill;
 321
 322         if (type == RFKILL_TYPE_ALL) {
 323                 int i;
 324
 325                 for (i = 0; i < NUM_RFKILL_TYPES; i++)
 326                         rfkill_global_states[i].cur = blocked;
 327         } else {
 328                 rfkill_global_states[type].cur = blocked;
 329         }
 330
 331         list_for_each_entry(rfkill, &rfkill_list, node) {
 332                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
 333                         continue;
 334
 335                 rfkill_set_block(rfkill, blocked);
 336         }
 337 }
 338
 339 /**
 340  * rfkill_switch_all - Toggle state of all switches of given type
 341  * @type: type of interfaces to be affected
 342  * @blocked: the new state
 343  *
 344  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
 345  * Please refer to __rfkill_switch_all() for details.
 346  *
 347  * Does nothing if the EPO lock is active.
 348  */
 349 void rfkill_switch_all(enum rfkill_type type, bool blocked)
 350 {
 351         if (atomic_read(&rfkill_input_disabled))
 352                 return;
 353
 354         mutex_lock(&rfkill_global_mutex);
 355
 356         if (!rfkill_epo_lock_active)
 357                 __rfkill_switch_all(type, blocked);
 358
 359         mutex_unlock(&rfkill_global_mutex);
 360 }
 361
 362 /**
 363  * rfkill_epo - emergency power off all transmitters
 364  *
 365  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
 366  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
 367  *
 368  * The global state before the EPO is saved and can be restored later
 369  * using rfkill_restore_states().
 370  */
 371 void rfkill_epo(void)
 372 {
 373         struct rfkill *rfkill;
 374         int i;
 375
 376         if (atomic_read(&rfkill_input_disabled))
 377                 return;
 378
 379         mutex_lock(&rfkill_global_mutex);
 380
 381         rfkill_epo_lock_active = true;
 382         list_for_each_entry(rfkill, &rfkill_list, node)
 383                 rfkill_set_block(rfkill, true);
 384
 385         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
 386                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
 387                 rfkill_global_states[i].cur = true;
 388         }
 389
 390         mutex_unlock(&rfkill_global_mutex);
 391 }
 392
 393 /**
 394  * rfkill_restore_states - restore global states
 395  *
 396  * Restore (and sync switches to) the global state from the
 397  * states in rfkill_default_states.  This can undo the effects of
 398  * a call to rfkill_epo().
 399  */
 400 void rfkill_restore_states(void)
 401 {
 402         int i;
 403
 404         if (atomic_read(&rfkill_input_disabled))
 405                 return;
 406
 407         mutex_lock(&rfkill_global_mutex);
 408
 409         rfkill_epo_lock_active = false;
 410         for (i = 0; i < NUM_RFKILL_TYPES; i++)
 411                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
 412         mutex_unlock(&rfkill_global_mutex);
 413 }
 414
 415 /**
 416  * rfkill_remove_epo_lock - unlock state changes
 417  *
 418  * Used by rfkill-input manually unlock state changes, when
 419  * the EPO switch is deactivated.
 420  */
 421 void rfkill_remove_epo_lock(void)
 422 {
 423         if (atomic_read(&rfkill_input_disabled))
 424                 return;
 425
 426         mutex_lock(&rfkill_global_mutex);
 427         rfkill_epo_lock_active = false;
 428         mutex_unlock(&rfkill_global_mutex);
 429 }
 430
 431 /**
 432  * rfkill_is_epo_lock_active - returns true EPO is active
 433  *
 434  * Returns 0 (false) if there is NOT an active EPO contidion,
 435  * and 1 (true) if there is an active EPO contition, which
 436  * locks all radios in one of the BLOCKED states.
 437  *
 438  * Can be called in atomic context.
 439  */
 440 bool rfkill_is_epo_lock_active(void)
 441 {
 442         return rfkill_epo_lock_active;
 443 }
 444
 445 /**
 446  * rfkill_get_global_sw_state - returns global state for a type
 447  * @type: the type to get the global state of
 448  *
 449  * Returns the current global state for a given wireless
 450  * device type.
 451  */
 452 bool rfkill_get_global_sw_state(const enum rfkill_type type)
 453 {
 454         return rfkill_global_states[type].cur;
 455 }
 456 #endif
 457
 458
 459 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
 460 {
 461         unsigned long flags;
 462         bool ret, prev;
 463
 464         BUG_ON(!rfkill);
 465
 466         spin_lock_irqsave(&rfkill->lock, flags);
 467         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
 468         if (blocked)
 469                 rfkill->state |= RFKILL_BLOCK_HW;
 470         else
 471                 rfkill->state &= ~RFKILL_BLOCK_HW;
 472         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
 473         spin_unlock_irqrestore(&rfkill->lock, flags);
 474
 475         rfkill_led_trigger_event(rfkill);
 476
 477         if (!rfkill->registered)
 478                 return ret;
 479
 480         if (prev != blocked)
 481                 schedule_work(&rfkill->uevent_work);
 482
 483         return ret;
 484 }
 485 EXPORT_SYMBOL(rfkill_set_hw_state);
 486
 487 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 488 {
 489         u32 bit = RFKILL_BLOCK_SW;
 490
 491         /* if in a ops->set_block right now, use other bit */
 492         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
 493                 bit = RFKILL_BLOCK_SW_PREV;
 494
 495         if (blocked)
 496                 rfkill->state |= bit;
 497         else
 498                 rfkill->state &= ~bit;
 499 }
 500
 501 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
 502 {
 503         unsigned long flags;
 504         bool prev, hwblock;
 505
 506         BUG_ON(!rfkill);
 507
 508         spin_lock_irqsave(&rfkill->lock, flags);
 509         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
 510         __rfkill_set_sw_state(rfkill, blocked);
 511         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
 512         blocked = blocked || hwblock;
 513         spin_unlock_irqrestore(&rfkill->lock, flags);
 514
 515         if (!rfkill->registered)
 516                 return blocked;
 517
 518         if (prev != blocked && !hwblock)
 519                 schedule_work(&rfkill->uevent_work);
 520
 521         rfkill_led_trigger_event(rfkill);
 522
 523         return blocked;
 524 }
 525 EXPORT_SYMBOL(rfkill_set_sw_state);
 526
 527 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
 528 {
 529         unsigned long flags;
 530
 531         BUG_ON(!rfkill);
 532         BUG_ON(rfkill->registered);
 533
 534         spin_lock_irqsave(&rfkill->lock, flags);
 535         __rfkill_set_sw_state(rfkill, blocked);
 536         rfkill->persistent = true;
 537         spin_unlock_irqrestore(&rfkill->lock, flags);
 538 }
 539 EXPORT_SYMBOL(rfkill_init_sw_state);
 540
 541 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
 542 {
 543         unsigned long flags;
 544         bool swprev, hwprev;
 545
 546         BUG_ON(!rfkill);
 547
 548         spin_lock_irqsave(&rfkill->lock, flags);
 549
 550         /*
 551          * No need to care about prev/setblock ... this is for uevent only
 552          * and that will get triggered by rfkill_set_block anyway.
 553          */
 554         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
 555         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
 556         __rfkill_set_sw_state(rfkill, sw);
 557         if (hw)
 558                 rfkill->state |= RFKILL_BLOCK_HW;
 559         else
 560                 rfkill->state &= ~RFKILL_BLOCK_HW;
 561
 562         spin_unlock_irqrestore(&rfkill->lock, flags);
 563
 564         if (!rfkill->registered) {
 565                 rfkill->persistent = true;
 566         } else {
 567                 if (swprev != sw || hwprev != hw)
 568                         schedule_work(&rfkill->uevent_work);
 569
 570                 rfkill_led_trigger_event(rfkill);
 571         }
 572 }
 573 EXPORT_SYMBOL(rfkill_set_states);
 574
 575 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 576                          char *buf)
 577 {
 578         struct rfkill *rfkill = to_rfkill(dev);
 579
 580         return sprintf(buf, "%s\n", rfkill->name);
 581 }
 582 static DEVICE_ATTR_RO(name);
 583
 584 static const char *rfkill_get_type_str(enum rfkill_type type)
 585 {
 586         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_NFC + 1);
 587
 588         switch (type) {
 589         case RFKILL_TYPE_WLAN:
 590                 return "wlan";
 591         case RFKILL_TYPE_BLUETOOTH:
 592                 return "bluetooth";
 593         case RFKILL_TYPE_UWB:
 594                 return "ultrawideband";
 595         case RFKILL_TYPE_WIMAX:
 596                 return "wimax";
 597         case RFKILL_TYPE_WWAN:
 598                 return "wwan";
 599         case RFKILL_TYPE_GPS:
 600                 return "gps";
 601         case RFKILL_TYPE_FM:
 602                 return "fm";
 603         case RFKILL_TYPE_NFC:
 604                 return "nfc";
 605         default:
 606                 BUG();
 607         }
 608 }
 609
 610 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 611                          char *buf)
 612 {
 613         struct rfkill *rfkill = to_rfkill(dev);
 614
 615         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
 616 }
 617 static DEVICE_ATTR_RO(type);
 618
 619 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
 620                           char *buf)
 621 {
 622         struct rfkill *rfkill = to_rfkill(dev);
 623
 624         return sprintf(buf, "%d\n", rfkill->idx);
 625 }
 626 static DEVICE_ATTR_RO(index);
 627
 628 static ssize_t persistent_show(struct device *dev,
 629                                struct device_attribute *attr, char *buf)
 630 {
 631         struct rfkill *rfkill = to_rfkill(dev);
 632
 633         return sprintf(buf, "%d\n", rfkill->persistent);
 634 }
 635 static DEVICE_ATTR_RO(persistent);
 636
 637 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
 638                          char *buf)
 639 {
 640         struct rfkill *rfkill = to_rfkill(dev);
 641
 642         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
 643 }
 644 static DEVICE_ATTR_RO(hard);
 645
 646 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
 647                          char *buf)
 648 {
 649         struct rfkill *rfkill = to_rfkill(dev);
 650
 651         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
 652 }
 653
 654 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
 655                           const char *buf, size_t count)
 656 {
 657         struct rfkill *rfkill = to_rfkill(dev);
 658         unsigned long state;
 659         int err;
 660
 661         if (!capable(CAP_NET_ADMIN))
 662                 return -EPERM;
 663
 664         err = kstrtoul(buf, 0, &state);
 665         if (err)
 666                 return err;
 667
 668         if (state > 1 )
 669                 return -EINVAL;
 670
 671         mutex_lock(&rfkill_global_mutex);
 672         rfkill_set_block(rfkill, state);
 673         mutex_unlock(&rfkill_global_mutex);
 674
 675         return count;
 676 }
 677 static DEVICE_ATTR_RW(soft);
 678
 679 static u8 user_state_from_blocked(unsigned long state)
 680 {
 681         if (state & RFKILL_BLOCK_HW)
 682                 return RFKILL_USER_STATE_HARD_BLOCKED;
 683         if (state & RFKILL_BLOCK_SW)
 684                 return RFKILL_USER_STATE_SOFT_BLOCKED;
 685
 686         return RFKILL_USER_STATE_UNBLOCKED;
 687 }
 688
 689 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 690                           char *buf)
 691 {
 692         struct rfkill *rfkill = to_rfkill(dev);
 693
 694         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
 695 }
 696
 697 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
 698                            const char *buf, size_t count)
 699 {
 700         struct rfkill *rfkill = to_rfkill(dev);
 701         unsigned long state;
 702         int err;
 703
 704         if (!capable(CAP_NET_ADMIN))
 705                 return -EPERM;
 706
 707         err = kstrtoul(buf, 0, &state);
 708         if (err)
 709                 return err;
 710
 711         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
 712             state != RFKILL_USER_STATE_UNBLOCKED)
 713                 return -EINVAL;
 714
 715         mutex_lock(&rfkill_global_mutex);
 716         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
 717         mutex_unlock(&rfkill_global_mutex);
 718
 719         return count;
 720 }
 721 static DEVICE_ATTR_RW(state);
 722
 723 static struct attribute *rfkill_dev_attrs[] = {
 724         &dev_attr_name.attr,
 725         &dev_attr_type.attr,
 726         &dev_attr_index.attr,
 727         &dev_attr_persistent.attr,
 728         &dev_attr_state.attr,
 729         &dev_attr_soft.attr,
 730         &dev_attr_hard.attr,
 731         NULL,
 732 };
 733 ATTRIBUTE_GROUPS(rfkill_dev);
 734
 735 static void rfkill_release(struct device *dev)
 736 {
 737         struct rfkill *rfkill = to_rfkill(dev);
 738
 739         kfree(rfkill);
 740 }
 741
 742 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
 743 {
 744         struct rfkill *rfkill = to_rfkill(dev);
 745         unsigned long flags;
 746         u32 state;
 747         int error;
 748
 749         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
 750         if (error)
 751                 return error;
 752         error = add_uevent_var(env, "RFKILL_TYPE=%s",
 753                                rfkill_get_type_str(rfkill->type));
 754         if (error)
 755                 return error;
 756         spin_lock_irqsave(&rfkill->lock, flags);
 757         state = rfkill->state;
 758         spin_unlock_irqrestore(&rfkill->lock, flags);
 759         error = add_uevent_var(env, "RFKILL_STATE=%d",
 760                                user_state_from_blocked(state));
 761         return error;
 762 }
 763
 764 void rfkill_pause_polling(struct rfkill *rfkill)
 765 {
 766         BUG_ON(!rfkill);
 767
 768         if (!rfkill->ops->poll)
 769                 return;
 770
 771         rfkill->polling_paused = true;
 772         cancel_delayed_work_sync(&rfkill->poll_work);
 773 }
 774 EXPORT_SYMBOL(rfkill_pause_polling);
 775
 776 void rfkill_resume_polling(struct rfkill *rfkill)
 777 {
 778         BUG_ON(!rfkill);
 779
 780         if (!rfkill->ops->poll)
 781                 return;
 782
 783         rfkill->polling_paused = false;
 784
 785         if (rfkill->suspended)
 786                 return;
 787
 788         queue_delayed_work(system_power_efficient_wq,
 789                            &rfkill->poll_work, 0);
 790 }
 791 EXPORT_SYMBOL(rfkill_resume_polling);
 792
 793 #ifdef CONFIG_PM_SLEEP
 794 static int rfkill_suspend(struct device *dev)
 795 {
 796         struct rfkill *rfkill = to_rfkill(dev);
 797
 798         rfkill->suspended = true;
 799         cancel_delayed_work_sync(&rfkill->poll_work);
 800
 801         return 0;
 802 }
 803
 804 static int rfkill_resume(struct device *dev)
 805 {
 806         struct rfkill *rfkill = to_rfkill(dev);
 807         bool cur;
 808
 809         rfkill->suspended = false;
 810
 811         if (!rfkill->persistent) {
 812                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
 813                 rfkill_set_block(rfkill, cur);
 814         }
 815
 816         if (rfkill->ops->poll && !rfkill->polling_paused)
 817                 queue_delayed_work(system_power_efficient_wq,
 818                                    &rfkill->poll_work, 0);
 819
 820         return 0;
 821 }
 822
 823 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
 824 #define RFKILL_PM_OPS (&rfkill_pm_ops)
 825 #else
 826 #define RFKILL_PM_OPS NULL
 827 #endif
 828
 829 static struct class rfkill_class = {
 830         .name           = "rfkill",
 831         .dev_release    = rfkill_release,
 832         .dev_groups     = rfkill_dev_groups,
 833         .dev_uevent     = rfkill_dev_uevent,
 834         .pm             = RFKILL_PM_OPS,
 835 };
 836
 837 bool rfkill_blocked(struct rfkill *rfkill)
 838 {
 839         unsigned long flags;
 840         u32 state;
 841
 842         spin_lock_irqsave(&rfkill->lock, flags);
 843         state = rfkill->state;
 844         spin_unlock_irqrestore(&rfkill->lock, flags);
 845
 846         return !!(state & RFKILL_BLOCK_ANY);
 847 }
 848 EXPORT_SYMBOL(rfkill_blocked);
 849
 850
 851 struct rfkill * __must_check rfkill_alloc(const char *name,
 852                                           struct device *parent,
 853                                           const enum rfkill_type type,
 854                                           const struct rfkill_ops *ops,
 855                                           void *ops_data)
 856 {
 857         struct rfkill *rfkill;
 858         struct device *dev;
 859
 860         if (WARN_ON(!ops))
 861                 return NULL;
 862
 863         if (WARN_ON(!ops->set_block))
 864                 return NULL;
 865
 866         if (WARN_ON(!name))
 867                 return NULL;
 868
 869         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
 870                 return NULL;
 871
 872         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
 873         if (!rfkill)
 874                 return NULL;
 875
 876         spin_lock_init(&rfkill->lock);
 877         INIT_LIST_HEAD(&rfkill->node);
 878         rfkill->type = type;
 879         strcpy(rfkill->name, name);
 880         rfkill->ops = ops;
 881         rfkill->data = ops_data;
 882
 883         dev = &rfkill->dev;
 884         dev->class = &rfkill_class;
 885         dev->parent = parent;
 886         device_initialize(dev);
 887
 888         return rfkill;
 889 }
 890 EXPORT_SYMBOL(rfkill_alloc);
 891
 892 static void rfkill_poll(struct work_struct *work)
 893 {
 894         struct rfkill *rfkill;
 895
 896         rfkill = container_of(work, struct rfkill, poll_work.work);
 897
 898         /*
 899          * Poll hardware state -- driver will use one of the
 900          * rfkill_set{,_hw,_sw}_state functions and use its
 901          * return value to update the current status.
 902          */
 903         rfkill->ops->poll(rfkill, rfkill->data);
 904
 905         queue_delayed_work(system_power_efficient_wq,
 906                 &rfkill->poll_work,
 907                 round_jiffies_relative(POLL_INTERVAL));
 908 }
 909
 910 static void rfkill_uevent_work(struct work_struct *work)
 911 {
 912         struct rfkill *rfkill;
 913
 914         rfkill = container_of(work, struct rfkill, uevent_work);
 915
 916         mutex_lock(&rfkill_global_mutex);
 917         rfkill_event(rfkill);
 918         mutex_unlock(&rfkill_global_mutex);
 919 }
 920
 921 static void rfkill_sync_work(struct work_struct *work)
 922 {
 923         struct rfkill *rfkill;
 924         bool cur;
 925
 926         rfkill = container_of(work, struct rfkill, sync_work);
 927
 928         mutex_lock(&rfkill_global_mutex);
 929         cur = rfkill_global_states[rfkill->type].cur;
 930         rfkill_set_block(rfkill, cur);
 931         mutex_unlock(&rfkill_global_mutex);
 932 }
 933
 934 int __must_check rfkill_register(struct rfkill *rfkill)
 935 {
 936         static unsigned long rfkill_no;
 937         struct device *dev = &rfkill->dev;
 938         int error;
 939
 940         BUG_ON(!rfkill);
 941
 942         mutex_lock(&rfkill_global_mutex);
 943
 944         if (rfkill->registered) {
 945                 error = -EALREADY;
 946                 goto unlock;
 947         }
 948
 949         rfkill->idx = rfkill_no;
 950         dev_set_name(dev, "rfkill%lu", rfkill_no);
 951         rfkill_no++;
 952
 953         list_add_tail(&rfkill->node, &rfkill_list);
 954
 955         error = device_add(dev);
 956         if (error)
 957                 goto remove;
 958
 959         error = rfkill_led_trigger_register(rfkill);
 960         if (error)
 961                 goto devdel;
 962
 963         rfkill->registered = true;
 964
 965         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
 966         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
 967         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
 968
 969         if (rfkill->ops->poll)
 970                 queue_delayed_work(system_power_efficient_wq,
 971                         &rfkill->poll_work,
 972                         round_jiffies_relative(POLL_INTERVAL));
 973
 974         if (!rfkill->persistent || rfkill_epo_lock_active) {
 975                 schedule_work(&rfkill->sync_work);
 976         } else {
 977 #ifdef CONFIG_RFKILL_INPUT
 978                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
 979
 980                 if (!atomic_read(&rfkill_input_disabled))
 981                         __rfkill_switch_all(rfkill->type, soft_blocked);
 982 #endif
 983         }
 984
 985         rfkill_send_events(rfkill, RFKILL_OP_ADD);
 986
 987         mutex_unlock(&rfkill_global_mutex);
 988         return 0;
 989
 990  devdel:
 991         device_del(&rfkill->dev);
 992  remove:
 993         list_del_init(&rfkill->node);
 994  unlock:
 995         mutex_unlock(&rfkill_global_mutex);
 996         return error;
 997 }
 998 EXPORT_SYMBOL(rfkill_register);
 999
1000 void rfkill_unregister(struct rfkill *rfkill)
1001 {
1002         BUG_ON(!rfkill);
1003
1004         if (rfkill->ops->poll)
1005                 cancel_delayed_work_sync(&rfkill->poll_work);
1006
1007         cancel_work_sync(&rfkill->uevent_work);
1008         cancel_work_sync(&rfkill->sync_work);
1009
1010         rfkill->registered = false;
1011
1012         device_del(&rfkill->dev);
1013
1014         mutex_lock(&rfkill_global_mutex);
1015         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1016         list_del_init(&rfkill->node);
1017         mutex_unlock(&rfkill_global_mutex);
1018
1019         rfkill_led_trigger_unregister(rfkill);
1020 }
1021 EXPORT_SYMBOL(rfkill_unregister);
1022
1023 void rfkill_destroy(struct rfkill *rfkill)
1024 {
1025         if (rfkill)
1026                 put_device(&rfkill->dev);
1027 }
1028 EXPORT_SYMBOL(rfkill_destroy);
1029
1030 static int rfkill_fop_open(struct inode *inode, struct file *file)
1031 {
1032         struct rfkill_data *data;
1033         struct rfkill *rfkill;
1034         struct rfkill_int_event *ev, *tmp;
1035
1036         data = kzalloc(sizeof(*data), GFP_KERNEL);
1037         if (!data)
1038                 return -ENOMEM;
1039
1040         INIT_LIST_HEAD(&data->events);
1041         mutex_init(&data->mtx);
1042         init_waitqueue_head(&data->read_wait);
1043
1044         mutex_lock(&rfkill_global_mutex);
1045         mutex_lock(&data->mtx);
1046         /*
1047          * start getting events from elsewhere but hold mtx to get
1048          * startup events added first
1049          */
1050
1051         list_for_each_entry(rfkill, &rfkill_list, node) {
1052                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1053                 if (!ev)
1054                         goto free;
1055                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1056                 list_add_tail(&ev->list, &data->events);
1057         }
1058         list_add(&data->list, &rfkill_fds);
1059         mutex_unlock(&data->mtx);
1060         mutex_unlock(&rfkill_global_mutex);
1061
1062         file->private_data = data;
1063
1064         return nonseekable_open(inode, file);
1065
1066  free:
1067         mutex_unlock(&data->mtx);
1068         mutex_unlock(&rfkill_global_mutex);
1069         mutex_destroy(&data->mtx);
1070         list_for_each_entry_safe(ev, tmp, &data->events, list)
1071                 kfree(ev);
1072         kfree(data);
1073         return -ENOMEM;
1074 }
1075
1076 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1077 {
1078         struct rfkill_data *data = file->private_data;
1079         unsigned int res = POLLOUT | POLLWRNORM;
1080
1081         poll_wait(file, &data->read_wait, wait);
1082
1083         mutex_lock(&data->mtx);
1084         if (!list_empty(&data->events))
1085                 res = POLLIN | POLLRDNORM;
1086         mutex_unlock(&data->mtx);
1087
1088         return res;
1089 }
1090
1091 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1092                                size_t count, loff_t *pos)
1093 {
1094         struct rfkill_data *data = file->private_data;
1095         struct rfkill_int_event *ev;
1096         unsigned long sz;
1097         int ret;
1098
1099         mutex_lock(&data->mtx);
1100
1101         while (list_empty(&data->events)) {
1102                 if (file->f_flags & O_NONBLOCK) {
1103                         ret = -EAGAIN;
1104                         goto out;
1105                 }
1106                 mutex_unlock(&data->mtx);
1107                 /* since we re-check and it just compares pointers,
1108                  * using !list_empty() without locking isn't a problem
1109                  */
1110                 ret = wait_event_interruptible(data->read_wait,
1111                                                !list_empty(&data->events));
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);