Merge branch 'linux-tegra-2.6.36' into android-tegra-2.6.36
[firefly-linux-kernel-4.4.55.git] / net / rfkill / core.c
1 /*
2  * Copyright (C) 2006 - 2007 Ivo van Doorn
3  * Copyright (C) 2007 Dmitry Torokhov
4  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the
18  * Free Software Foundation, Inc.,
19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20  */
21
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/workqueue.h>
26 #include <linux/capability.h>
27 #include <linux/list.h>
28 #include <linux/mutex.h>
29 #include <linux/rfkill.h>
30 #include <linux/sched.h>
31 #include <linux/spinlock.h>
32 #include <linux/miscdevice.h>
33 #include <linux/wait.h>
34 #include <linux/poll.h>
35 #include <linux/fs.h>
36 #include <linux/slab.h>
37
38 #include "rfkill.h"
39
40 #define POLL_INTERVAL           (5 * HZ)
41
42 #define RFKILL_BLOCK_HW         BIT(0)
43 #define RFKILL_BLOCK_SW         BIT(1)
44 #define RFKILL_BLOCK_SW_PREV    BIT(2)
45 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
46                                  RFKILL_BLOCK_SW |\
47                                  RFKILL_BLOCK_SW_PREV)
48 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
49
50 struct rfkill {
51         spinlock_t              lock;
52
53         const char              *name;
54         enum rfkill_type        type;
55
56         unsigned long           state;
57
58         u32                     idx;
59
60         bool                    registered;
61         bool                    persistent;
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 };
78 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
79
80 struct rfkill_int_event {
81         struct list_head        list;
82         struct rfkill_event     ev;
83 };
84
85 struct rfkill_data {
86         struct list_head        list;
87         struct list_head        events;
88         struct mutex            mtx;
89         wait_queue_head_t       read_wait;
90         bool                    input_handler;
91 };
92
93
94 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
95 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
96 MODULE_DESCRIPTION("RF switch support");
97 MODULE_LICENSE("GPL");
98
99
100 /*
101  * The locking here should be made much smarter, we currently have
102  * a bit of a stupid situation because drivers might want to register
103  * the rfkill struct under their own lock, and take this lock during
104  * rfkill method calls -- which will cause an AB-BA deadlock situation.
105  *
106  * To fix that, we need to rework this code here to be mostly lock-free
107  * and only use the mutex for list manipulations, not to protect the
108  * various other global variables. Then we can avoid holding the mutex
109  * around driver operations, and all is happy.
110  */
111 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
112 static DEFINE_MUTEX(rfkill_global_mutex);
113 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
114
115 static unsigned int rfkill_default_state = 1;
116 module_param_named(default_state, rfkill_default_state, uint, 0444);
117 MODULE_PARM_DESC(default_state,
118                  "Default initial state for all radio types, 0 = radio off");
119
120 static struct {
121         bool cur, sav;
122 } rfkill_global_states[NUM_RFKILL_TYPES];
123
124 static bool rfkill_epo_lock_active;
125
126
127 #ifdef CONFIG_RFKILL_LEDS
128 static void rfkill_led_trigger_event(struct rfkill *rfkill)
129 {
130         struct led_trigger *trigger;
131
132         if (!rfkill->registered)
133                 return;
134
135         trigger = &rfkill->led_trigger;
136
137         if (rfkill->state & RFKILL_BLOCK_ANY)
138                 led_trigger_event(trigger, LED_OFF);
139         else
140                 led_trigger_event(trigger, LED_FULL);
141 }
142
143 static void rfkill_led_trigger_activate(struct led_classdev *led)
144 {
145         struct rfkill *rfkill;
146
147         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
148
149         rfkill_led_trigger_event(rfkill);
150 }
151
152 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
153 {
154         return rfkill->led_trigger.name;
155 }
156 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
157
158 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
159 {
160         BUG_ON(!rfkill);
161
162         rfkill->ledtrigname = name;
163 }
164 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
165
166 static int rfkill_led_trigger_register(struct rfkill *rfkill)
167 {
168         rfkill->led_trigger.name = rfkill->ledtrigname
169                                         ? : dev_name(&rfkill->dev);
170         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
171         return led_trigger_register(&rfkill->led_trigger);
172 }
173
174 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
175 {
176         led_trigger_unregister(&rfkill->led_trigger);
177 }
178 #else
179 static void rfkill_led_trigger_event(struct rfkill *rfkill)
180 {
181 }
182
183 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
184 {
185         return 0;
186 }
187
188 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
189 {
190 }
191 #endif /* CONFIG_RFKILL_LEDS */
192
193 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
194                               enum rfkill_operation op)
195 {
196         unsigned long flags;
197
198         ev->idx = rfkill->idx;
199         ev->type = rfkill->type;
200         ev->op = op;
201
202         spin_lock_irqsave(&rfkill->lock, flags);
203         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
204         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
205                                         RFKILL_BLOCK_SW_PREV));
206         spin_unlock_irqrestore(&rfkill->lock, flags);
207 }
208
209 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
210 {
211         struct rfkill_data *data;
212         struct rfkill_int_event *ev;
213
214         list_for_each_entry(data, &rfkill_fds, list) {
215                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
216                 if (!ev)
217                         continue;
218                 rfkill_fill_event(&ev->ev, rfkill, op);
219                 mutex_lock(&data->mtx);
220                 list_add_tail(&ev->list, &data->events);
221                 mutex_unlock(&data->mtx);
222                 wake_up_interruptible(&data->read_wait);
223         }
224 }
225
226 static void rfkill_event(struct rfkill *rfkill)
227 {
228         if (!rfkill->registered)
229                 return;
230
231         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
232
233         /* also send event to /dev/rfkill */
234         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
235 }
236
237 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
238                                   bool blocked, bool *change)
239 {
240         unsigned long flags;
241         bool prev, any;
242
243         BUG_ON(!rfkill);
244
245         spin_lock_irqsave(&rfkill->lock, flags);
246         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
247         if (blocked)
248                 rfkill->state |= RFKILL_BLOCK_HW;
249         else
250                 rfkill->state &= ~RFKILL_BLOCK_HW;
251         *change = prev != blocked;
252         any = rfkill->state & RFKILL_BLOCK_ANY;
253         spin_unlock_irqrestore(&rfkill->lock, flags);
254
255         rfkill_led_trigger_event(rfkill);
256
257         return any;
258 }
259
260 /**
261  * rfkill_set_block - wrapper for set_block method
262  *
263  * @rfkill: the rfkill struct to use
264  * @blocked: the new software state
265  *
266  * Calls the set_block method (when applicable) and handles notifications
267  * etc. as well.
268  */
269 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
270 {
271         unsigned long flags;
272         int err;
273
274         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
275                 return;
276
277         /*
278          * Some platforms (...!) generate input events which affect the
279          * _hard_ kill state -- whenever something tries to change the
280          * current software state query the hardware state too.
281          */
282         if (rfkill->ops->query)
283                 rfkill->ops->query(rfkill, rfkill->data);
284
285         spin_lock_irqsave(&rfkill->lock, flags);
286         if (rfkill->state & RFKILL_BLOCK_SW)
287                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
288         else
289                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
290
291         if (blocked)
292                 rfkill->state |= RFKILL_BLOCK_SW;
293         else
294                 rfkill->state &= ~RFKILL_BLOCK_SW;
295
296         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
297         spin_unlock_irqrestore(&rfkill->lock, flags);
298
299         err = rfkill->ops->set_block(rfkill->data, blocked);
300
301         spin_lock_irqsave(&rfkill->lock, flags);
302         if (err) {
303                 /*
304                  * Failed -- reset status to _prev, this may be different
305                  * from what set set _PREV to earlier in this function
306                  * if rfkill_set_sw_state was invoked.
307                  */
308                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
309                         rfkill->state |= RFKILL_BLOCK_SW;
310                 else
311                         rfkill->state &= ~RFKILL_BLOCK_SW;
312         }
313         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
314         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
315         spin_unlock_irqrestore(&rfkill->lock, flags);
316
317         rfkill_led_trigger_event(rfkill);
318         rfkill_event(rfkill);
319 }
320
321 #ifdef CONFIG_RFKILL_INPUT
322 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
323
324 /**
325  * __rfkill_switch_all - Toggle state of all switches of given type
326  * @type: type of interfaces to be affected
327  * @state: the new state
328  *
329  * This function sets the state of all switches of given type,
330  * unless a specific switch is claimed by userspace (in which case,
331  * that switch is left alone) or suspended.
332  *
333  * Caller must have acquired rfkill_global_mutex.
334  */
335 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
336 {
337         struct rfkill *rfkill;
338
339         rfkill_global_states[type].cur = blocked;
340         list_for_each_entry(rfkill, &rfkill_list, node) {
341                 if (rfkill->type != type)
342                         continue;
343
344                 rfkill_set_block(rfkill, blocked);
345         }
346 }
347
348 /**
349  * rfkill_switch_all - Toggle state of all switches of given type
350  * @type: type of interfaces to be affected
351  * @state: the new state
352  *
353  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
354  * Please refer to __rfkill_switch_all() for details.
355  *
356  * Does nothing if the EPO lock is active.
357  */
358 void rfkill_switch_all(enum rfkill_type type, bool blocked)
359 {
360         if (atomic_read(&rfkill_input_disabled))
361                 return;
362
363         mutex_lock(&rfkill_global_mutex);
364
365         if (!rfkill_epo_lock_active)
366                 __rfkill_switch_all(type, blocked);
367
368         mutex_unlock(&rfkill_global_mutex);
369 }
370
371 /**
372  * rfkill_epo - emergency power off all transmitters
373  *
374  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
375  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
376  *
377  * The global state before the EPO is saved and can be restored later
378  * using rfkill_restore_states().
379  */
380 void rfkill_epo(void)
381 {
382         struct rfkill *rfkill;
383         int i;
384
385         if (atomic_read(&rfkill_input_disabled))
386                 return;
387
388         mutex_lock(&rfkill_global_mutex);
389
390         rfkill_epo_lock_active = true;
391         list_for_each_entry(rfkill, &rfkill_list, node)
392                 rfkill_set_block(rfkill, true);
393
394         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
395                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
396                 rfkill_global_states[i].cur = true;
397         }
398
399         mutex_unlock(&rfkill_global_mutex);
400 }
401
402 /**
403  * rfkill_restore_states - restore global states
404  *
405  * Restore (and sync switches to) the global state from the
406  * states in rfkill_default_states.  This can undo the effects of
407  * a call to rfkill_epo().
408  */
409 void rfkill_restore_states(void)
410 {
411         int i;
412
413         if (atomic_read(&rfkill_input_disabled))
414                 return;
415
416         mutex_lock(&rfkill_global_mutex);
417
418         rfkill_epo_lock_active = false;
419         for (i = 0; i < NUM_RFKILL_TYPES; i++)
420                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
421         mutex_unlock(&rfkill_global_mutex);
422 }
423
424 /**
425  * rfkill_remove_epo_lock - unlock state changes
426  *
427  * Used by rfkill-input manually unlock state changes, when
428  * the EPO switch is deactivated.
429  */
430 void rfkill_remove_epo_lock(void)
431 {
432         if (atomic_read(&rfkill_input_disabled))
433                 return;
434
435         mutex_lock(&rfkill_global_mutex);
436         rfkill_epo_lock_active = false;
437         mutex_unlock(&rfkill_global_mutex);
438 }
439
440 /**
441  * rfkill_is_epo_lock_active - returns true EPO is active
442  *
443  * Returns 0 (false) if there is NOT an active EPO contidion,
444  * and 1 (true) if there is an active EPO contition, which
445  * locks all radios in one of the BLOCKED states.
446  *
447  * Can be called in atomic context.
448  */
449 bool rfkill_is_epo_lock_active(void)
450 {
451         return rfkill_epo_lock_active;
452 }
453
454 /**
455  * rfkill_get_global_sw_state - returns global state for a type
456  * @type: the type to get the global state of
457  *
458  * Returns the current global state for a given wireless
459  * device type.
460  */
461 bool rfkill_get_global_sw_state(const enum rfkill_type type)
462 {
463         return rfkill_global_states[type].cur;
464 }
465 #endif
466
467
468 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
469 {
470         bool ret, change;
471
472         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
473
474         if (!rfkill->registered)
475                 return ret;
476
477         if (change)
478                 schedule_work(&rfkill->uevent_work);
479
480         return ret;
481 }
482 EXPORT_SYMBOL(rfkill_set_hw_state);
483
484 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
485 {
486         u32 bit = RFKILL_BLOCK_SW;
487
488         /* if in a ops->set_block right now, use other bit */
489         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
490                 bit = RFKILL_BLOCK_SW_PREV;
491
492         if (blocked)
493                 rfkill->state |= bit;
494         else
495                 rfkill->state &= ~bit;
496 }
497
498 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
499 {
500         unsigned long flags;
501         bool prev, hwblock;
502
503         BUG_ON(!rfkill);
504
505         spin_lock_irqsave(&rfkill->lock, flags);
506         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
507         __rfkill_set_sw_state(rfkill, blocked);
508         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
509         blocked = blocked || hwblock;
510         spin_unlock_irqrestore(&rfkill->lock, flags);
511
512         if (!rfkill->registered)
513                 return blocked;
514
515         if (prev != blocked && !hwblock)
516                 schedule_work(&rfkill->uevent_work);
517
518         rfkill_led_trigger_event(rfkill);
519
520         return blocked;
521 }
522 EXPORT_SYMBOL(rfkill_set_sw_state);
523
524 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
525 {
526         unsigned long flags;
527
528         BUG_ON(!rfkill);
529         BUG_ON(rfkill->registered);
530
531         spin_lock_irqsave(&rfkill->lock, flags);
532         __rfkill_set_sw_state(rfkill, blocked);
533         rfkill->persistent = true;
534         spin_unlock_irqrestore(&rfkill->lock, flags);
535 }
536 EXPORT_SYMBOL(rfkill_init_sw_state);
537
538 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
539 {
540         unsigned long flags;
541         bool swprev, hwprev;
542
543         BUG_ON(!rfkill);
544
545         spin_lock_irqsave(&rfkill->lock, flags);
546
547         /*
548          * No need to care about prev/setblock ... this is for uevent only
549          * and that will get triggered by rfkill_set_block anyway.
550          */
551         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
552         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
553         __rfkill_set_sw_state(rfkill, sw);
554         if (hw)
555                 rfkill->state |= RFKILL_BLOCK_HW;
556         else
557                 rfkill->state &= ~RFKILL_BLOCK_HW;
558
559         spin_unlock_irqrestore(&rfkill->lock, flags);
560
561         if (!rfkill->registered) {
562                 rfkill->persistent = true;
563         } else {
564                 if (swprev != sw || hwprev != hw)
565                         schedule_work(&rfkill->uevent_work);
566
567                 rfkill_led_trigger_event(rfkill);
568         }
569 }
570 EXPORT_SYMBOL(rfkill_set_states);
571
572 static ssize_t rfkill_name_show(struct device *dev,
573                                 struct device_attribute *attr,
574                                 char *buf)
575 {
576         struct rfkill *rfkill = to_rfkill(dev);
577
578         return sprintf(buf, "%s\n", rfkill->name);
579 }
580
581 static const char *rfkill_get_type_str(enum rfkill_type type)
582 {
583         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_FM + 1);
584
585         switch (type) {
586         case RFKILL_TYPE_WLAN:
587                 return "wlan";
588         case RFKILL_TYPE_BLUETOOTH:
589                 return "bluetooth";
590         case RFKILL_TYPE_UWB:
591                 return "ultrawideband";
592         case RFKILL_TYPE_WIMAX:
593                 return "wimax";
594         case RFKILL_TYPE_WWAN:
595                 return "wwan";
596         case RFKILL_TYPE_GPS:
597                 return "gps";
598         case RFKILL_TYPE_FM:
599                 return "fm";
600         default:
601                 BUG();
602         }
603 }
604
605 static ssize_t rfkill_type_show(struct device *dev,
606                                 struct device_attribute *attr,
607                                 char *buf)
608 {
609         struct rfkill *rfkill = to_rfkill(dev);
610
611         return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
612 }
613
614 static ssize_t rfkill_idx_show(struct device *dev,
615                                struct device_attribute *attr,
616                                char *buf)
617 {
618         struct rfkill *rfkill = to_rfkill(dev);
619
620         return sprintf(buf, "%d\n", rfkill->idx);
621 }
622
623 static ssize_t rfkill_persistent_show(struct device *dev,
624                                struct device_attribute *attr,
625                                char *buf)
626 {
627         struct rfkill *rfkill = to_rfkill(dev);
628
629         return sprintf(buf, "%d\n", rfkill->persistent);
630 }
631
632 static ssize_t rfkill_hard_show(struct device *dev,
633                                  struct device_attribute *attr,
634                                  char *buf)
635 {
636         struct rfkill *rfkill = to_rfkill(dev);
637
638         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
639 }
640
641 static ssize_t rfkill_soft_show(struct device *dev,
642                                  struct device_attribute *attr,
643                                  char *buf)
644 {
645         struct rfkill *rfkill = to_rfkill(dev);
646
647         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
648 }
649
650 static ssize_t rfkill_soft_store(struct device *dev,
651                                   struct device_attribute *attr,
652                                   const char *buf, size_t count)
653 {
654         struct rfkill *rfkill = to_rfkill(dev);
655         unsigned long state;
656         int err;
657
658         if (!capable(CAP_NET_ADMIN))
659                 return -EPERM;
660
661         err = strict_strtoul(buf, 0, &state);
662         if (err)
663                 return err;
664
665         if (state > 1 )
666                 return -EINVAL;
667
668         mutex_lock(&rfkill_global_mutex);
669         rfkill_set_block(rfkill, state);
670         mutex_unlock(&rfkill_global_mutex);
671
672         return err ?: count;
673 }
674
675 static u8 user_state_from_blocked(unsigned long state)
676 {
677         if (state & RFKILL_BLOCK_HW)
678                 return RFKILL_USER_STATE_HARD_BLOCKED;
679         if (state & RFKILL_BLOCK_SW)
680                 return RFKILL_USER_STATE_SOFT_BLOCKED;
681
682         return RFKILL_USER_STATE_UNBLOCKED;
683 }
684
685 static ssize_t rfkill_state_show(struct device *dev,
686                                  struct device_attribute *attr,
687                                  char *buf)
688 {
689         struct rfkill *rfkill = to_rfkill(dev);
690
691         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
692 }
693
694 static ssize_t rfkill_state_store(struct device *dev,
695                                   struct device_attribute *attr,
696                                   const char *buf, size_t count)
697 {
698         struct rfkill *rfkill = to_rfkill(dev);
699         unsigned long state;
700         int err;
701
702         if (!capable(CAP_NET_ADMIN))
703                 return -EPERM;
704
705         err = strict_strtoul(buf, 0, &state);
706         if (err)
707                 return err;
708
709         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
710             state != RFKILL_USER_STATE_UNBLOCKED)
711                 return -EINVAL;
712
713         mutex_lock(&rfkill_global_mutex);
714         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
715         mutex_unlock(&rfkill_global_mutex);
716
717         return err ?: count;
718 }
719
720 static ssize_t rfkill_claim_show(struct device *dev,
721                                  struct device_attribute *attr,
722                                  char *buf)
723 {
724         return sprintf(buf, "%d\n", 0);
725 }
726
727 static ssize_t rfkill_claim_store(struct device *dev,
728                                   struct device_attribute *attr,
729                                   const char *buf, size_t count)
730 {
731         return -EOPNOTSUPP;
732 }
733
734 static struct device_attribute rfkill_dev_attrs[] = {
735         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
736         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
737         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
738         __ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
739         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
740         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
741         __ATTR(soft, S_IRUGO|S_IWUSR, rfkill_soft_show, rfkill_soft_store),
742         __ATTR(hard, S_IRUGO, rfkill_hard_show, NULL),
743         __ATTR_NULL
744 };
745
746 static void rfkill_release(struct device *dev)
747 {
748         struct rfkill *rfkill = to_rfkill(dev);
749
750         kfree(rfkill);
751 }
752
753 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
754 {
755         struct rfkill *rfkill = to_rfkill(dev);
756         unsigned long flags;
757         u32 state;
758         int error;
759
760         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
761         if (error)
762                 return error;
763         error = add_uevent_var(env, "RFKILL_TYPE=%s",
764                                rfkill_get_type_str(rfkill->type));
765         if (error)
766                 return error;
767         spin_lock_irqsave(&rfkill->lock, flags);
768         state = rfkill->state;
769         spin_unlock_irqrestore(&rfkill->lock, flags);
770         error = add_uevent_var(env, "RFKILL_STATE=%d",
771                                user_state_from_blocked(state));
772         return error;
773 }
774
775 void rfkill_pause_polling(struct rfkill *rfkill)
776 {
777         BUG_ON(!rfkill);
778
779         if (!rfkill->ops->poll)
780                 return;
781
782         cancel_delayed_work_sync(&rfkill->poll_work);
783 }
784 EXPORT_SYMBOL(rfkill_pause_polling);
785
786 #ifdef CONFIG_RFKILL_PM
787 void rfkill_resume_polling(struct rfkill *rfkill)
788 {
789         BUG_ON(!rfkill);
790
791         if (!rfkill->ops->poll)
792                 return;
793
794         schedule_work(&rfkill->poll_work.work);
795 }
796 EXPORT_SYMBOL(rfkill_resume_polling);
797
798 static int rfkill_suspend(struct device *dev, pm_message_t state)
799 {
800         struct rfkill *rfkill = to_rfkill(dev);
801
802         rfkill_pause_polling(rfkill);
803
804         return 0;
805 }
806
807 static int rfkill_resume(struct device *dev)
808 {
809         struct rfkill *rfkill = to_rfkill(dev);
810         bool cur;
811
812         if (!rfkill->persistent) {
813                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
814                 rfkill_set_block(rfkill, cur);
815         }
816
817         rfkill_resume_polling(rfkill);
818
819         return 0;
820 }
821 #endif
822
823 static struct class rfkill_class = {
824         .name           = "rfkill",
825         .dev_release    = rfkill_release,
826         .dev_attrs      = rfkill_dev_attrs,
827         .dev_uevent     = rfkill_dev_uevent,
828 #ifdef CONFIG_RFKILL_PM
829         .suspend        = rfkill_suspend,
830         .resume         = rfkill_resume,
831 #endif
832 };
833
834 bool rfkill_blocked(struct rfkill *rfkill)
835 {
836         unsigned long flags;
837         u32 state;
838
839         spin_lock_irqsave(&rfkill->lock, flags);
840         state = rfkill->state;
841         spin_unlock_irqrestore(&rfkill->lock, flags);
842
843         return !!(state & RFKILL_BLOCK_ANY);
844 }
845 EXPORT_SYMBOL(rfkill_blocked);
846
847
848 struct rfkill * __must_check rfkill_alloc(const char *name,
849                                           struct device *parent,
850                                           const enum rfkill_type type,
851                                           const struct rfkill_ops *ops,
852                                           void *ops_data)
853 {
854         struct rfkill *rfkill;
855         struct device *dev;
856
857         if (WARN_ON(!ops))
858                 return NULL;
859
860         if (WARN_ON(!ops->set_block))
861                 return NULL;
862
863         if (WARN_ON(!name))
864                 return NULL;
865
866         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
867                 return NULL;
868
869         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
870         if (!rfkill)
871                 return NULL;
872
873         spin_lock_init(&rfkill->lock);
874         INIT_LIST_HEAD(&rfkill->node);
875         rfkill->type = type;
876         rfkill->name = name;
877         rfkill->ops = ops;
878         rfkill->data = ops_data;
879
880         dev = &rfkill->dev;
881         dev->class = &rfkill_class;
882         dev->parent = parent;
883         device_initialize(dev);
884
885         return rfkill;
886 }
887 EXPORT_SYMBOL(rfkill_alloc);
888
889 static void rfkill_poll(struct work_struct *work)
890 {
891         struct rfkill *rfkill;
892
893         rfkill = container_of(work, struct rfkill, poll_work.work);
894
895         /*
896          * Poll hardware state -- driver will use one of the
897          * rfkill_set{,_hw,_sw}_state functions and use its
898          * return value to update the current status.
899          */
900         rfkill->ops->poll(rfkill, rfkill->data);
901
902         schedule_delayed_work(&rfkill->poll_work,
903                 round_jiffies_relative(POLL_INTERVAL));
904 }
905
906 static void rfkill_uevent_work(struct work_struct *work)
907 {
908         struct rfkill *rfkill;
909
910         rfkill = container_of(work, struct rfkill, uevent_work);
911
912         mutex_lock(&rfkill_global_mutex);
913         rfkill_event(rfkill);
914         mutex_unlock(&rfkill_global_mutex);
915 }
916
917 static void rfkill_sync_work(struct work_struct *work)
918 {
919         struct rfkill *rfkill;
920         bool cur;
921
922         rfkill = container_of(work, struct rfkill, sync_work);
923
924         mutex_lock(&rfkill_global_mutex);
925         cur = rfkill_global_states[rfkill->type].cur;
926         rfkill_set_block(rfkill, cur);
927         mutex_unlock(&rfkill_global_mutex);
928 }
929
930 int __must_check rfkill_register(struct rfkill *rfkill)
931 {
932         static unsigned long rfkill_no;
933         struct device *dev = &rfkill->dev;
934         int error;
935
936         BUG_ON(!rfkill);
937
938         mutex_lock(&rfkill_global_mutex);
939
940         if (rfkill->registered) {
941                 error = -EALREADY;
942                 goto unlock;
943         }
944
945         rfkill->idx = rfkill_no;
946         dev_set_name(dev, "rfkill%lu", rfkill_no);
947         rfkill_no++;
948
949         list_add_tail(&rfkill->node, &rfkill_list);
950
951         error = device_add(dev);
952         if (error)
953                 goto remove;
954
955         error = rfkill_led_trigger_register(rfkill);
956         if (error)
957                 goto devdel;
958
959         rfkill->registered = true;
960
961         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
962         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
963         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
964
965         if (rfkill->ops->poll)
966                 schedule_delayed_work(&rfkill->poll_work,
967                         round_jiffies_relative(POLL_INTERVAL));
968
969         if (!rfkill->persistent || rfkill_epo_lock_active) {
970                 schedule_work(&rfkill->sync_work);
971         } else {
972 #ifdef CONFIG_RFKILL_INPUT
973                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
974
975                 if (!atomic_read(&rfkill_input_disabled))
976                         __rfkill_switch_all(rfkill->type, soft_blocked);
977 #endif
978         }
979
980         rfkill_send_events(rfkill, RFKILL_OP_ADD);
981
982         mutex_unlock(&rfkill_global_mutex);
983         return 0;
984
985  devdel:
986         device_del(&rfkill->dev);
987  remove:
988         list_del_init(&rfkill->node);
989  unlock:
990         mutex_unlock(&rfkill_global_mutex);
991         return error;
992 }
993 EXPORT_SYMBOL(rfkill_register);
994
995 void rfkill_unregister(struct rfkill *rfkill)
996 {
997         BUG_ON(!rfkill);
998
999         if (rfkill->ops->poll)
1000                 cancel_delayed_work_sync(&rfkill->poll_work);
1001
1002         cancel_work_sync(&rfkill->uevent_work);
1003         cancel_work_sync(&rfkill->sync_work);
1004
1005         rfkill->registered = false;
1006
1007         device_del(&rfkill->dev);
1008
1009         mutex_lock(&rfkill_global_mutex);
1010         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1011         list_del_init(&rfkill->node);
1012         mutex_unlock(&rfkill_global_mutex);
1013
1014         rfkill_led_trigger_unregister(rfkill);
1015 }
1016 EXPORT_SYMBOL(rfkill_unregister);
1017
1018 void rfkill_destroy(struct rfkill *rfkill)
1019 {
1020         if (rfkill)
1021                 put_device(&rfkill->dev);
1022 }
1023 EXPORT_SYMBOL(rfkill_destroy);
1024
1025 static int rfkill_fop_open(struct inode *inode, struct file *file)
1026 {
1027         struct rfkill_data *data;
1028         struct rfkill *rfkill;
1029         struct rfkill_int_event *ev, *tmp;
1030
1031         data = kzalloc(sizeof(*data), GFP_KERNEL);
1032         if (!data)
1033                 return -ENOMEM;
1034
1035         INIT_LIST_HEAD(&data->events);
1036         mutex_init(&data->mtx);
1037         init_waitqueue_head(&data->read_wait);
1038
1039         mutex_lock(&rfkill_global_mutex);
1040         mutex_lock(&data->mtx);
1041         /*
1042          * start getting events from elsewhere but hold mtx to get
1043          * startup events added first
1044          */
1045         list_add(&data->list, &rfkill_fds);
1046
1047         list_for_each_entry(rfkill, &rfkill_list, node) {
1048                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1049                 if (!ev)
1050                         goto free;
1051                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1052                 list_add_tail(&ev->list, &data->events);
1053         }
1054         mutex_unlock(&data->mtx);
1055         mutex_unlock(&rfkill_global_mutex);
1056
1057         file->private_data = data;
1058
1059         return nonseekable_open(inode, file);
1060
1061  free:
1062         mutex_unlock(&data->mtx);
1063         mutex_unlock(&rfkill_global_mutex);
1064         mutex_destroy(&data->mtx);
1065         list_for_each_entry_safe(ev, tmp, &data->events, list)
1066                 kfree(ev);
1067         kfree(data);
1068         return -ENOMEM;
1069 }
1070
1071 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1072 {
1073         struct rfkill_data *data = file->private_data;
1074         unsigned int res = POLLOUT | POLLWRNORM;
1075
1076         poll_wait(file, &data->read_wait, wait);
1077
1078         mutex_lock(&data->mtx);
1079         if (!list_empty(&data->events))
1080                 res = POLLIN | POLLRDNORM;
1081         mutex_unlock(&data->mtx);
1082
1083         return res;
1084 }
1085
1086 static bool rfkill_readable(struct rfkill_data *data)
1087 {
1088         bool r;
1089
1090         mutex_lock(&data->mtx);
1091         r = !list_empty(&data->events);
1092         mutex_unlock(&data->mtx);
1093
1094         return r;
1095 }
1096
1097 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1098                                size_t count, loff_t *pos)
1099 {
1100         struct rfkill_data *data = file->private_data;
1101         struct rfkill_int_event *ev;
1102         unsigned long sz;
1103         int ret;
1104
1105         mutex_lock(&data->mtx);
1106
1107         while (list_empty(&data->events)) {
1108                 if (file->f_flags & O_NONBLOCK) {
1109                         ret = -EAGAIN;
1110                         goto out;
1111                 }
1112                 mutex_unlock(&data->mtx);
1113                 ret = wait_event_interruptible(data->read_wait,
1114                                                rfkill_readable(data));
1115                 mutex_lock(&data->mtx);
1116
1117                 if (ret)
1118                         goto out;
1119         }
1120
1121         ev = list_first_entry(&data->events, struct rfkill_int_event,
1122                                 list);
1123
1124         sz = min_t(unsigned long, sizeof(ev->ev), count);
1125         ret = sz;
1126         if (copy_to_user(buf, &ev->ev, sz))
1127                 ret = -EFAULT;
1128
1129         list_del(&ev->list);
1130         kfree(ev);
1131  out:
1132         mutex_unlock(&data->mtx);
1133         return ret;
1134 }
1135
1136 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1137                                 size_t count, loff_t *pos)
1138 {
1139         struct rfkill *rfkill;
1140         struct rfkill_event ev;
1141
1142         /* we don't need the 'hard' variable but accept it */
1143         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1144                 return -EINVAL;
1145
1146         /*
1147          * Copy as much data as we can accept into our 'ev' buffer,
1148          * but tell userspace how much we've copied so it can determine
1149          * our API version even in a write() call, if it cares.
1150          */
1151         count = min(count, sizeof(ev));
1152         if (copy_from_user(&ev, buf, count))
1153                 return -EFAULT;
1154
1155         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1156                 return -EINVAL;
1157
1158         if (ev.type >= NUM_RFKILL_TYPES)
1159                 return -EINVAL;
1160
1161         mutex_lock(&rfkill_global_mutex);
1162
1163         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1164                 if (ev.type == RFKILL_TYPE_ALL) {
1165                         enum rfkill_type i;
1166                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1167                                 rfkill_global_states[i].cur = ev.soft;
1168                 } else {
1169                         rfkill_global_states[ev.type].cur = ev.soft;
1170                 }
1171         }
1172
1173         list_for_each_entry(rfkill, &rfkill_list, node) {
1174                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1175                         continue;
1176
1177                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1178                         continue;
1179
1180                 rfkill_set_block(rfkill, ev.soft);
1181         }
1182         mutex_unlock(&rfkill_global_mutex);
1183
1184         return count;
1185 }
1186
1187 static int rfkill_fop_release(struct inode *inode, struct file *file)
1188 {
1189         struct rfkill_data *data = file->private_data;
1190         struct rfkill_int_event *ev, *tmp;
1191
1192         mutex_lock(&rfkill_global_mutex);
1193         list_del(&data->list);
1194         mutex_unlock(&rfkill_global_mutex);
1195
1196         mutex_destroy(&data->mtx);
1197         list_for_each_entry_safe(ev, tmp, &data->events, list)
1198                 kfree(ev);
1199
1200 #ifdef CONFIG_RFKILL_INPUT
1201         if (data->input_handler)
1202                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1203                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1204 #endif
1205
1206         kfree(data);
1207
1208         return 0;
1209 }
1210
1211 #ifdef CONFIG_RFKILL_INPUT
1212 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1213                              unsigned long arg)
1214 {
1215         struct rfkill_data *data = file->private_data;
1216
1217         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1218                 return -ENOSYS;
1219
1220         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1221                 return -ENOSYS;
1222
1223         mutex_lock(&data->mtx);
1224
1225         if (!data->input_handler) {
1226                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1227                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1228                 data->input_handler = true;
1229         }
1230
1231         mutex_unlock(&data->mtx);
1232
1233         return 0;
1234 }
1235 #endif
1236
1237 static const struct file_operations rfkill_fops = {
1238         .owner          = THIS_MODULE,
1239         .open           = rfkill_fop_open,
1240         .read           = rfkill_fop_read,
1241         .write          = rfkill_fop_write,
1242         .poll           = rfkill_fop_poll,
1243         .release        = rfkill_fop_release,
1244 #ifdef CONFIG_RFKILL_INPUT
1245         .unlocked_ioctl = rfkill_fop_ioctl,
1246         .compat_ioctl   = rfkill_fop_ioctl,
1247 #endif
1248 };
1249
1250 static struct miscdevice rfkill_miscdev = {
1251         .name   = "rfkill",
1252         .fops   = &rfkill_fops,
1253         .minor  = MISC_DYNAMIC_MINOR,
1254 };
1255
1256 static int __init rfkill_init(void)
1257 {
1258         int error;
1259         int i;
1260
1261         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1262                 rfkill_global_states[i].cur = !rfkill_default_state;
1263
1264         error = class_register(&rfkill_class);
1265         if (error)
1266                 goto out;
1267
1268         error = misc_register(&rfkill_miscdev);
1269         if (error) {
1270                 class_unregister(&rfkill_class);
1271                 goto out;
1272         }
1273
1274 #ifdef CONFIG_RFKILL_INPUT
1275         error = rfkill_handler_init();
1276         if (error) {
1277                 misc_deregister(&rfkill_miscdev);
1278                 class_unregister(&rfkill_class);
1279                 goto out;
1280         }
1281 #endif
1282
1283  out:
1284         return error;
1285 }
1286 subsys_initcall(rfkill_init);
1287
1288 static void __exit rfkill_exit(void)
1289 {
1290 #ifdef CONFIG_RFKILL_INPUT
1291         rfkill_handler_exit();
1292 #endif
1293         misc_deregister(&rfkill_miscdev);
1294         class_unregister(&rfkill_class);
1295 }
1296 module_exit(rfkill_exit);