rfkill: add function to query state
[linux-3.10.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/spinlock.h>
31 #include <linux/miscdevice.h>
32 #include <linux/wait.h>
33 #include <linux/poll.h>
34 #include <linux/fs.h>
35
36 #include "rfkill.h"
37
38 #define POLL_INTERVAL           (5 * HZ)
39
40 #define RFKILL_BLOCK_HW         BIT(0)
41 #define RFKILL_BLOCK_SW         BIT(1)
42 #define RFKILL_BLOCK_SW_PREV    BIT(2)
43 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
44                                  RFKILL_BLOCK_SW |\
45                                  RFKILL_BLOCK_SW_PREV)
46 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
47
48 struct rfkill {
49         spinlock_t              lock;
50
51         const char              *name;
52         enum rfkill_type        type;
53
54         unsigned long           state;
55
56         u32                     idx;
57
58         bool                    registered;
59         bool                    suspended;
60
61         const struct rfkill_ops *ops;
62         void                    *data;
63
64 #ifdef CONFIG_RFKILL_LEDS
65         struct led_trigger      led_trigger;
66         const char              *ledtrigname;
67 #endif
68
69         struct device           dev;
70         struct list_head        node;
71
72         struct delayed_work     poll_work;
73         struct work_struct      uevent_work;
74         struct work_struct      sync_work;
75 };
76 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
77
78 struct rfkill_int_event {
79         struct list_head        list;
80         struct rfkill_event     ev;
81 };
82
83 struct rfkill_data {
84         struct list_head        list;
85         struct list_head        events;
86         struct mutex            mtx;
87         wait_queue_head_t       read_wait;
88         bool                    input_handler;
89 };
90
91
92 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
93 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
94 MODULE_DESCRIPTION("RF switch support");
95 MODULE_LICENSE("GPL");
96
97
98 /*
99  * The locking here should be made much smarter, we currently have
100  * a bit of a stupid situation because drivers might want to register
101  * the rfkill struct under their own lock, and take this lock during
102  * rfkill method calls -- which will cause an AB-BA deadlock situation.
103  *
104  * To fix that, we need to rework this code here to be mostly lock-free
105  * and only use the mutex for list manipulations, not to protect the
106  * various other global variables. Then we can avoid holding the mutex
107  * around driver operations, and all is happy.
108  */
109 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
110 static DEFINE_MUTEX(rfkill_global_mutex);
111 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
112
113 static unsigned int rfkill_default_state = 1;
114 module_param_named(default_state, rfkill_default_state, uint, 0444);
115 MODULE_PARM_DESC(default_state,
116                  "Default initial state for all radio types, 0 = radio off");
117
118 static struct {
119         bool cur, def;
120 } rfkill_global_states[NUM_RFKILL_TYPES];
121
122 static unsigned long rfkill_states_default_locked;
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 || rfkill->suspended)
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         /*
275          * Some platforms (...!) generate input events which affect the
276          * _hard_ kill state -- whenever something tries to change the
277          * current software state query the hardware state too.
278          */
279         if (rfkill->ops->query)
280                 rfkill->ops->query(rfkill, rfkill->data);
281
282         spin_lock_irqsave(&rfkill->lock, flags);
283         if (rfkill->state & RFKILL_BLOCK_SW)
284                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
285         else
286                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
287
288         if (blocked)
289                 rfkill->state |= RFKILL_BLOCK_SW;
290         else
291                 rfkill->state &= ~RFKILL_BLOCK_SW;
292
293         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
294         spin_unlock_irqrestore(&rfkill->lock, flags);
295
296         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
297                 return;
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].def = 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].def);
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 void rfkill_set_global_sw_state(const enum rfkill_type type, bool blocked)
468 {
469         BUG_ON(type == RFKILL_TYPE_ALL);
470
471         mutex_lock(&rfkill_global_mutex);
472
473         /* don't allow unblock when epo */
474         if (rfkill_epo_lock_active && !blocked)
475                 goto out;
476
477         /* too late */
478         if (rfkill_states_default_locked & BIT(type))
479                 goto out;
480
481         rfkill_states_default_locked |= BIT(type);
482
483         rfkill_global_states[type].cur = blocked;
484         rfkill_global_states[type].def = blocked;
485  out:
486         mutex_unlock(&rfkill_global_mutex);
487 }
488 EXPORT_SYMBOL(rfkill_set_global_sw_state);
489
490
491 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
492 {
493         bool ret, change;
494
495         ret = __rfkill_set_hw_state(rfkill, blocked, &change);
496
497         if (!rfkill->registered)
498                 return ret;
499
500         if (change)
501                 schedule_work(&rfkill->uevent_work);
502
503         return ret;
504 }
505 EXPORT_SYMBOL(rfkill_set_hw_state);
506
507 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
508 {
509         u32 bit = RFKILL_BLOCK_SW;
510
511         /* if in a ops->set_block right now, use other bit */
512         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
513                 bit = RFKILL_BLOCK_SW_PREV;
514
515         if (blocked)
516                 rfkill->state |= bit;
517         else
518                 rfkill->state &= ~bit;
519 }
520
521 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
522 {
523         unsigned long flags;
524         bool prev, hwblock;
525
526         BUG_ON(!rfkill);
527
528         spin_lock_irqsave(&rfkill->lock, flags);
529         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
530         __rfkill_set_sw_state(rfkill, blocked);
531         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
532         blocked = blocked || hwblock;
533         spin_unlock_irqrestore(&rfkill->lock, flags);
534
535         if (!rfkill->registered)
536                 return blocked;
537
538         if (prev != blocked && !hwblock)
539                 schedule_work(&rfkill->uevent_work);
540
541         rfkill_led_trigger_event(rfkill);
542
543         return blocked;
544 }
545 EXPORT_SYMBOL(rfkill_set_sw_state);
546
547 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
548 {
549         unsigned long flags;
550         bool swprev, hwprev;
551
552         BUG_ON(!rfkill);
553
554         spin_lock_irqsave(&rfkill->lock, flags);
555
556         /*
557          * No need to care about prev/setblock ... this is for uevent only
558          * and that will get triggered by rfkill_set_block anyway.
559          */
560         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
561         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
562         __rfkill_set_sw_state(rfkill, sw);
563
564         spin_unlock_irqrestore(&rfkill->lock, flags);
565
566         if (!rfkill->registered)
567                 return;
568
569         if (swprev != sw || hwprev != hw)
570                 schedule_work(&rfkill->uevent_work);
571
572         rfkill_led_trigger_event(rfkill);
573 }
574 EXPORT_SYMBOL(rfkill_set_states);
575
576 static ssize_t rfkill_name_show(struct device *dev,
577                                 struct device_attribute *attr,
578                                 char *buf)
579 {
580         struct rfkill *rfkill = to_rfkill(dev);
581
582         return sprintf(buf, "%s\n", rfkill->name);
583 }
584
585 static const char *rfkill_get_type_str(enum rfkill_type type)
586 {
587         switch (type) {
588         case RFKILL_TYPE_WLAN:
589                 return "wlan";
590         case RFKILL_TYPE_BLUETOOTH:
591                 return "bluetooth";
592         case RFKILL_TYPE_UWB:
593                 return "ultrawideband";
594         case RFKILL_TYPE_WIMAX:
595                 return "wimax";
596         case RFKILL_TYPE_WWAN:
597                 return "wwan";
598         default:
599                 BUG();
600         }
601
602         BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_WWAN + 1);
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 u8 user_state_from_blocked(unsigned long state)
624 {
625         if (state & RFKILL_BLOCK_HW)
626                 return RFKILL_USER_STATE_HARD_BLOCKED;
627         if (state & RFKILL_BLOCK_SW)
628                 return RFKILL_USER_STATE_SOFT_BLOCKED;
629
630         return RFKILL_USER_STATE_UNBLOCKED;
631 }
632
633 static ssize_t rfkill_state_show(struct device *dev,
634                                  struct device_attribute *attr,
635                                  char *buf)
636 {
637         struct rfkill *rfkill = to_rfkill(dev);
638         unsigned long flags;
639         u32 state;
640
641         spin_lock_irqsave(&rfkill->lock, flags);
642         state = rfkill->state;
643         spin_unlock_irqrestore(&rfkill->lock, flags);
644
645         return sprintf(buf, "%d\n", user_state_from_blocked(state));
646 }
647
648 static ssize_t rfkill_state_store(struct device *dev,
649                                   struct device_attribute *attr,
650                                   const char *buf, size_t count)
651 {
652         /*
653          * The intention was that userspace can only take control over
654          * a given device when/if rfkill-input doesn't control it due
655          * to user_claim. Since user_claim is currently unsupported,
656          * we never support changing the state from userspace -- this
657          * can be implemented again later.
658          */
659
660         return -EPERM;
661 }
662
663 static ssize_t rfkill_claim_show(struct device *dev,
664                                  struct device_attribute *attr,
665                                  char *buf)
666 {
667         return sprintf(buf, "%d\n", 0);
668 }
669
670 static ssize_t rfkill_claim_store(struct device *dev,
671                                   struct device_attribute *attr,
672                                   const char *buf, size_t count)
673 {
674         return -EOPNOTSUPP;
675 }
676
677 static struct device_attribute rfkill_dev_attrs[] = {
678         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
679         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
680         __ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
681         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
682         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
683         __ATTR_NULL
684 };
685
686 static void rfkill_release(struct device *dev)
687 {
688         struct rfkill *rfkill = to_rfkill(dev);
689
690         kfree(rfkill);
691 }
692
693 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
694 {
695         struct rfkill *rfkill = to_rfkill(dev);
696         unsigned long flags;
697         u32 state;
698         int error;
699
700         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
701         if (error)
702                 return error;
703         error = add_uevent_var(env, "RFKILL_TYPE=%s",
704                                rfkill_get_type_str(rfkill->type));
705         if (error)
706                 return error;
707         spin_lock_irqsave(&rfkill->lock, flags);
708         state = rfkill->state;
709         spin_unlock_irqrestore(&rfkill->lock, flags);
710         error = add_uevent_var(env, "RFKILL_STATE=%d",
711                                user_state_from_blocked(state));
712         return error;
713 }
714
715 void rfkill_pause_polling(struct rfkill *rfkill)
716 {
717         BUG_ON(!rfkill);
718
719         if (!rfkill->ops->poll)
720                 return;
721
722         cancel_delayed_work_sync(&rfkill->poll_work);
723 }
724 EXPORT_SYMBOL(rfkill_pause_polling);
725
726 void rfkill_resume_polling(struct rfkill *rfkill)
727 {
728         BUG_ON(!rfkill);
729
730         if (!rfkill->ops->poll)
731                 return;
732
733         schedule_work(&rfkill->poll_work.work);
734 }
735 EXPORT_SYMBOL(rfkill_resume_polling);
736
737 static int rfkill_suspend(struct device *dev, pm_message_t state)
738 {
739         struct rfkill *rfkill = to_rfkill(dev);
740
741         rfkill_pause_polling(rfkill);
742
743         rfkill->suspended = true;
744
745         return 0;
746 }
747
748 static int rfkill_resume(struct device *dev)
749 {
750         struct rfkill *rfkill = to_rfkill(dev);
751         bool cur;
752
753         mutex_lock(&rfkill_global_mutex);
754         cur = rfkill_global_states[rfkill->type].cur;
755         rfkill_set_block(rfkill, cur);
756         mutex_unlock(&rfkill_global_mutex);
757
758         rfkill->suspended = false;
759
760         schedule_work(&rfkill->uevent_work);
761
762         rfkill_resume_polling(rfkill);
763
764         return 0;
765 }
766
767 static struct class rfkill_class = {
768         .name           = "rfkill",
769         .dev_release    = rfkill_release,
770         .dev_attrs      = rfkill_dev_attrs,
771         .dev_uevent     = rfkill_dev_uevent,
772         .suspend        = rfkill_suspend,
773         .resume         = rfkill_resume,
774 };
775
776 bool rfkill_blocked(struct rfkill *rfkill)
777 {
778         unsigned long flags;
779         u32 state;
780
781         spin_lock_irqsave(&rfkill->lock, flags);
782         state = rfkill->state;
783         spin_unlock_irqrestore(&rfkill->lock, flags);
784
785         return !!(state & RFKILL_BLOCK_ANY);
786 }
787 EXPORT_SYMBOL(rfkill_blocked);
788
789
790 struct rfkill * __must_check rfkill_alloc(const char *name,
791                                           struct device *parent,
792                                           const enum rfkill_type type,
793                                           const struct rfkill_ops *ops,
794                                           void *ops_data)
795 {
796         struct rfkill *rfkill;
797         struct device *dev;
798
799         if (WARN_ON(!ops))
800                 return NULL;
801
802         if (WARN_ON(!ops->set_block))
803                 return NULL;
804
805         if (WARN_ON(!name))
806                 return NULL;
807
808         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
809                 return NULL;
810
811         rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
812         if (!rfkill)
813                 return NULL;
814
815         spin_lock_init(&rfkill->lock);
816         INIT_LIST_HEAD(&rfkill->node);
817         rfkill->type = type;
818         rfkill->name = name;
819         rfkill->ops = ops;
820         rfkill->data = ops_data;
821
822         dev = &rfkill->dev;
823         dev->class = &rfkill_class;
824         dev->parent = parent;
825         device_initialize(dev);
826
827         return rfkill;
828 }
829 EXPORT_SYMBOL(rfkill_alloc);
830
831 static void rfkill_poll(struct work_struct *work)
832 {
833         struct rfkill *rfkill;
834
835         rfkill = container_of(work, struct rfkill, poll_work.work);
836
837         /*
838          * Poll hardware state -- driver will use one of the
839          * rfkill_set{,_hw,_sw}_state functions and use its
840          * return value to update the current status.
841          */
842         rfkill->ops->poll(rfkill, rfkill->data);
843
844         schedule_delayed_work(&rfkill->poll_work,
845                 round_jiffies_relative(POLL_INTERVAL));
846 }
847
848 static void rfkill_uevent_work(struct work_struct *work)
849 {
850         struct rfkill *rfkill;
851
852         rfkill = container_of(work, struct rfkill, uevent_work);
853
854         mutex_lock(&rfkill_global_mutex);
855         rfkill_event(rfkill);
856         mutex_unlock(&rfkill_global_mutex);
857 }
858
859 static void rfkill_sync_work(struct work_struct *work)
860 {
861         struct rfkill *rfkill;
862         bool cur;
863
864         rfkill = container_of(work, struct rfkill, sync_work);
865
866         mutex_lock(&rfkill_global_mutex);
867         cur = rfkill_global_states[rfkill->type].cur;
868         rfkill_set_block(rfkill, cur);
869         mutex_unlock(&rfkill_global_mutex);
870 }
871
872 int __must_check rfkill_register(struct rfkill *rfkill)
873 {
874         static unsigned long rfkill_no;
875         struct device *dev = &rfkill->dev;
876         int error;
877
878         BUG_ON(!rfkill);
879
880         mutex_lock(&rfkill_global_mutex);
881
882         if (rfkill->registered) {
883                 error = -EALREADY;
884                 goto unlock;
885         }
886
887         rfkill->idx = rfkill_no;
888         dev_set_name(dev, "rfkill%lu", rfkill_no);
889         rfkill_no++;
890
891         if (!(rfkill_states_default_locked & BIT(rfkill->type))) {
892                 /* first of its kind */
893                 BUILD_BUG_ON(NUM_RFKILL_TYPES >
894                         sizeof(rfkill_states_default_locked) * 8);
895                 rfkill_states_default_locked |= BIT(rfkill->type);
896                 rfkill_global_states[rfkill->type].cur =
897                         rfkill_global_states[rfkill->type].def;
898         }
899
900         list_add_tail(&rfkill->node, &rfkill_list);
901
902         error = device_add(dev);
903         if (error)
904                 goto remove;
905
906         error = rfkill_led_trigger_register(rfkill);
907         if (error)
908                 goto devdel;
909
910         rfkill->registered = true;
911
912         if (rfkill->ops->poll) {
913                 INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
914                 schedule_delayed_work(&rfkill->poll_work,
915                         round_jiffies_relative(POLL_INTERVAL));
916         }
917
918         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
919
920         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
921         schedule_work(&rfkill->sync_work);
922         rfkill_send_events(rfkill, RFKILL_OP_ADD);
923
924         mutex_unlock(&rfkill_global_mutex);
925         return 0;
926
927  devdel:
928         device_del(&rfkill->dev);
929  remove:
930         list_del_init(&rfkill->node);
931  unlock:
932         mutex_unlock(&rfkill_global_mutex);
933         return error;
934 }
935 EXPORT_SYMBOL(rfkill_register);
936
937 void rfkill_unregister(struct rfkill *rfkill)
938 {
939         BUG_ON(!rfkill);
940
941         if (rfkill->ops->poll)
942                 cancel_delayed_work_sync(&rfkill->poll_work);
943
944         cancel_work_sync(&rfkill->uevent_work);
945         cancel_work_sync(&rfkill->sync_work);
946
947         rfkill->registered = false;
948
949         device_del(&rfkill->dev);
950
951         mutex_lock(&rfkill_global_mutex);
952         rfkill_send_events(rfkill, RFKILL_OP_DEL);
953         list_del_init(&rfkill->node);
954         mutex_unlock(&rfkill_global_mutex);
955
956         rfkill_led_trigger_unregister(rfkill);
957 }
958 EXPORT_SYMBOL(rfkill_unregister);
959
960 void rfkill_destroy(struct rfkill *rfkill)
961 {
962         if (rfkill)
963                 put_device(&rfkill->dev);
964 }
965 EXPORT_SYMBOL(rfkill_destroy);
966
967 static int rfkill_fop_open(struct inode *inode, struct file *file)
968 {
969         struct rfkill_data *data;
970         struct rfkill *rfkill;
971         struct rfkill_int_event *ev, *tmp;
972
973         data = kzalloc(sizeof(*data), GFP_KERNEL);
974         if (!data)
975                 return -ENOMEM;
976
977         INIT_LIST_HEAD(&data->events);
978         mutex_init(&data->mtx);
979         init_waitqueue_head(&data->read_wait);
980
981         mutex_lock(&rfkill_global_mutex);
982         mutex_lock(&data->mtx);
983         /*
984          * start getting events from elsewhere but hold mtx to get
985          * startup events added first
986          */
987         list_add(&data->list, &rfkill_fds);
988
989         list_for_each_entry(rfkill, &rfkill_list, node) {
990                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
991                 if (!ev)
992                         goto free;
993                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
994                 list_add_tail(&ev->list, &data->events);
995         }
996         mutex_unlock(&data->mtx);
997         mutex_unlock(&rfkill_global_mutex);
998
999         file->private_data = data;
1000
1001         return nonseekable_open(inode, file);
1002
1003  free:
1004         mutex_unlock(&data->mtx);
1005         mutex_unlock(&rfkill_global_mutex);
1006         mutex_destroy(&data->mtx);
1007         list_for_each_entry_safe(ev, tmp, &data->events, list)
1008                 kfree(ev);
1009         kfree(data);
1010         return -ENOMEM;
1011 }
1012
1013 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1014 {
1015         struct rfkill_data *data = file->private_data;
1016         unsigned int res = POLLOUT | POLLWRNORM;
1017
1018         poll_wait(file, &data->read_wait, wait);
1019
1020         mutex_lock(&data->mtx);
1021         if (!list_empty(&data->events))
1022                 res = POLLIN | POLLRDNORM;
1023         mutex_unlock(&data->mtx);
1024
1025         return res;
1026 }
1027
1028 static bool rfkill_readable(struct rfkill_data *data)
1029 {
1030         bool r;
1031
1032         mutex_lock(&data->mtx);
1033         r = !list_empty(&data->events);
1034         mutex_unlock(&data->mtx);
1035
1036         return r;
1037 }
1038
1039 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1040                                size_t count, loff_t *pos)
1041 {
1042         struct rfkill_data *data = file->private_data;
1043         struct rfkill_int_event *ev;
1044         unsigned long sz;
1045         int ret;
1046
1047         mutex_lock(&data->mtx);
1048
1049         while (list_empty(&data->events)) {
1050                 if (file->f_flags & O_NONBLOCK) {
1051                         ret = -EAGAIN;
1052                         goto out;
1053                 }
1054                 mutex_unlock(&data->mtx);
1055                 ret = wait_event_interruptible(data->read_wait,
1056                                                rfkill_readable(data));
1057                 mutex_lock(&data->mtx);
1058
1059                 if (ret)
1060                         goto out;
1061         }
1062
1063         ev = list_first_entry(&data->events, struct rfkill_int_event,
1064                                 list);
1065
1066         sz = min_t(unsigned long, sizeof(ev->ev), count);
1067         ret = sz;
1068         if (copy_to_user(buf, &ev->ev, sz))
1069                 ret = -EFAULT;
1070
1071         list_del(&ev->list);
1072         kfree(ev);
1073  out:
1074         mutex_unlock(&data->mtx);
1075         return ret;
1076 }
1077
1078 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1079                                 size_t count, loff_t *pos)
1080 {
1081         struct rfkill *rfkill;
1082         struct rfkill_event ev;
1083
1084         /* we don't need the 'hard' variable but accept it */
1085         if (count < sizeof(ev) - 1)
1086                 return -EINVAL;
1087
1088         if (copy_from_user(&ev, buf, sizeof(ev) - 1))
1089                 return -EFAULT;
1090
1091         if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1092                 return -EINVAL;
1093
1094         if (ev.type >= NUM_RFKILL_TYPES)
1095                 return -EINVAL;
1096
1097         mutex_lock(&rfkill_global_mutex);
1098
1099         if (ev.op == RFKILL_OP_CHANGE_ALL) {
1100                 if (ev.type == RFKILL_TYPE_ALL) {
1101                         enum rfkill_type i;
1102                         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1103                                 rfkill_global_states[i].cur = ev.soft;
1104                 } else {
1105                         rfkill_global_states[ev.type].cur = ev.soft;
1106                 }
1107         }
1108
1109         list_for_each_entry(rfkill, &rfkill_list, node) {
1110                 if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1111                         continue;
1112
1113                 if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1114                         continue;
1115
1116                 rfkill_set_block(rfkill, ev.soft);
1117         }
1118         mutex_unlock(&rfkill_global_mutex);
1119
1120         return count;
1121 }
1122
1123 static int rfkill_fop_release(struct inode *inode, struct file *file)
1124 {
1125         struct rfkill_data *data = file->private_data;
1126         struct rfkill_int_event *ev, *tmp;
1127
1128         mutex_lock(&rfkill_global_mutex);
1129         list_del(&data->list);
1130         mutex_unlock(&rfkill_global_mutex);
1131
1132         mutex_destroy(&data->mtx);
1133         list_for_each_entry_safe(ev, tmp, &data->events, list)
1134                 kfree(ev);
1135
1136 #ifdef CONFIG_RFKILL_INPUT
1137         if (data->input_handler)
1138                 atomic_dec(&rfkill_input_disabled);
1139 #endif
1140
1141         kfree(data);
1142
1143         return 0;
1144 }
1145
1146 #ifdef CONFIG_RFKILL_INPUT
1147 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1148                              unsigned long arg)
1149 {
1150         struct rfkill_data *data = file->private_data;
1151
1152         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1153                 return -ENOSYS;
1154
1155         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1156                 return -ENOSYS;
1157
1158         mutex_lock(&data->mtx);
1159
1160         if (!data->input_handler) {
1161                 atomic_inc(&rfkill_input_disabled);
1162                 data->input_handler = true;
1163         }
1164
1165         mutex_unlock(&data->mtx);
1166
1167         return 0;
1168 }
1169 #endif
1170
1171 static const struct file_operations rfkill_fops = {
1172         .open           = rfkill_fop_open,
1173         .read           = rfkill_fop_read,
1174         .write          = rfkill_fop_write,
1175         .poll           = rfkill_fop_poll,
1176         .release        = rfkill_fop_release,
1177 #ifdef CONFIG_RFKILL_INPUT
1178         .unlocked_ioctl = rfkill_fop_ioctl,
1179         .compat_ioctl   = rfkill_fop_ioctl,
1180 #endif
1181 };
1182
1183 static struct miscdevice rfkill_miscdev = {
1184         .name   = "rfkill",
1185         .fops   = &rfkill_fops,
1186         .minor  = MISC_DYNAMIC_MINOR,
1187 };
1188
1189 static int __init rfkill_init(void)
1190 {
1191         int error;
1192         int i;
1193
1194         for (i = 0; i < NUM_RFKILL_TYPES; i++)
1195                 rfkill_global_states[i].def = !rfkill_default_state;
1196
1197         error = class_register(&rfkill_class);
1198         if (error)
1199                 goto out;
1200
1201         error = misc_register(&rfkill_miscdev);
1202         if (error) {
1203                 class_unregister(&rfkill_class);
1204                 goto out;
1205         }
1206
1207 #ifdef CONFIG_RFKILL_INPUT
1208         error = rfkill_handler_init();
1209         if (error) {
1210                 misc_deregister(&rfkill_miscdev);
1211                 class_unregister(&rfkill_class);
1212                 goto out;
1213         }
1214 #endif
1215
1216  out:
1217         return error;
1218 }
1219 subsys_initcall(rfkill_init);
1220
1221 static void __exit rfkill_exit(void)
1222 {
1223 #ifdef CONFIG_RFKILL_INPUT
1224         rfkill_handler_exit();
1225 #endif
1226         misc_deregister(&rfkill_miscdev);
1227         class_unregister(&rfkill_class);
1228 }
1229 module_exit(rfkill_exit);