xref: /linux/net/rfkill/core.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
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, which may be different
286 		 * from what we have 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 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
306 {
307 	int i;
308 
309 	if (type != RFKILL_TYPE_ALL) {
310 		rfkill_global_states[type].cur = blocked;
311 		return;
312 	}
313 
314 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
315 		rfkill_global_states[i].cur = blocked;
316 }
317 
318 #ifdef CONFIG_RFKILL_INPUT
319 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
320 
321 /**
322  * __rfkill_switch_all - Toggle state of all switches of given type
323  * @type: type of interfaces to be affected
324  * @blocked: the new state
325  *
326  * This function sets the state of all switches of given type,
327  * unless a specific switch is suspended.
328  *
329  * Caller must have acquired rfkill_global_mutex.
330  */
331 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
332 {
333 	struct rfkill *rfkill;
334 
335 	rfkill_update_global_state(type, blocked);
336 	list_for_each_entry(rfkill, &rfkill_list, node) {
337 		if (rfkill->type != type && type != RFKILL_TYPE_ALL)
338 			continue;
339 
340 		rfkill_set_block(rfkill, blocked);
341 	}
342 }
343 
344 /**
345  * rfkill_switch_all - Toggle state of all switches of given type
346  * @type: type of interfaces to be affected
347  * @blocked: the new state
348  *
349  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
350  * Please refer to __rfkill_switch_all() for details.
351  *
352  * Does nothing if the EPO lock is active.
353  */
354 void rfkill_switch_all(enum rfkill_type type, bool blocked)
355 {
356 	if (atomic_read(&rfkill_input_disabled))
357 		return;
358 
359 	mutex_lock(&rfkill_global_mutex);
360 
361 	if (!rfkill_epo_lock_active)
362 		__rfkill_switch_all(type, blocked);
363 
364 	mutex_unlock(&rfkill_global_mutex);
365 }
366 
367 /**
368  * rfkill_epo - emergency power off all transmitters
369  *
370  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
371  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
372  *
373  * The global state before the EPO is saved and can be restored later
374  * using rfkill_restore_states().
375  */
376 void rfkill_epo(void)
377 {
378 	struct rfkill *rfkill;
379 	int i;
380 
381 	if (atomic_read(&rfkill_input_disabled))
382 		return;
383 
384 	mutex_lock(&rfkill_global_mutex);
385 
386 	rfkill_epo_lock_active = true;
387 	list_for_each_entry(rfkill, &rfkill_list, node)
388 		rfkill_set_block(rfkill, true);
389 
390 	for (i = 0; i < NUM_RFKILL_TYPES; i++) {
391 		rfkill_global_states[i].sav = rfkill_global_states[i].cur;
392 		rfkill_global_states[i].cur = true;
393 	}
394 
395 	mutex_unlock(&rfkill_global_mutex);
396 }
397 
398 /**
399  * rfkill_restore_states - restore global states
400  *
401  * Restore (and sync switches to) the global state from the
402  * states in rfkill_default_states.  This can undo the effects of
403  * a call to rfkill_epo().
404  */
405 void rfkill_restore_states(void)
406 {
407 	int i;
408 
409 	if (atomic_read(&rfkill_input_disabled))
410 		return;
411 
412 	mutex_lock(&rfkill_global_mutex);
413 
414 	rfkill_epo_lock_active = false;
415 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
416 		__rfkill_switch_all(i, rfkill_global_states[i].sav);
417 	mutex_unlock(&rfkill_global_mutex);
418 }
419 
420 /**
421  * rfkill_remove_epo_lock - unlock state changes
422  *
423  * Used by rfkill-input manually unlock state changes, when
424  * the EPO switch is deactivated.
425  */
426 void rfkill_remove_epo_lock(void)
427 {
428 	if (atomic_read(&rfkill_input_disabled))
429 		return;
430 
431 	mutex_lock(&rfkill_global_mutex);
432 	rfkill_epo_lock_active = false;
433 	mutex_unlock(&rfkill_global_mutex);
434 }
435 
436 /**
437  * rfkill_is_epo_lock_active - returns true EPO is active
438  *
439  * Returns 0 (false) if there is NOT an active EPO contidion,
440  * and 1 (true) if there is an active EPO contition, which
441  * locks all radios in one of the BLOCKED states.
442  *
443  * Can be called in atomic context.
444  */
445 bool rfkill_is_epo_lock_active(void)
446 {
447 	return rfkill_epo_lock_active;
448 }
449 
450 /**
451  * rfkill_get_global_sw_state - returns global state for a type
452  * @type: the type to get the global state of
453  *
454  * Returns the current global state for a given wireless
455  * device type.
456  */
457 bool rfkill_get_global_sw_state(const enum rfkill_type type)
458 {
459 	return rfkill_global_states[type].cur;
460 }
461 #endif
462 
463 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
464 {
465 	unsigned long flags;
466 	bool ret, prev;
467 
468 	BUG_ON(!rfkill);
469 
470 	spin_lock_irqsave(&rfkill->lock, flags);
471 	prev = !!(rfkill->state & RFKILL_BLOCK_HW);
472 	if (blocked)
473 		rfkill->state |= RFKILL_BLOCK_HW;
474 	else
475 		rfkill->state &= ~RFKILL_BLOCK_HW;
476 	ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
477 	spin_unlock_irqrestore(&rfkill->lock, flags);
478 
479 	rfkill_led_trigger_event(rfkill);
480 
481 	if (!rfkill->registered)
482 		return ret;
483 
484 	if (prev != blocked)
485 		schedule_work(&rfkill->uevent_work);
486 
487 	return ret;
488 }
489 EXPORT_SYMBOL(rfkill_set_hw_state);
490 
491 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
492 {
493 	u32 bit = RFKILL_BLOCK_SW;
494 
495 	/* if in a ops->set_block right now, use other bit */
496 	if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
497 		bit = RFKILL_BLOCK_SW_PREV;
498 
499 	if (blocked)
500 		rfkill->state |= bit;
501 	else
502 		rfkill->state &= ~bit;
503 }
504 
505 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
506 {
507 	unsigned long flags;
508 	bool prev, hwblock;
509 
510 	BUG_ON(!rfkill);
511 
512 	spin_lock_irqsave(&rfkill->lock, flags);
513 	prev = !!(rfkill->state & RFKILL_BLOCK_SW);
514 	__rfkill_set_sw_state(rfkill, blocked);
515 	hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
516 	blocked = blocked || hwblock;
517 	spin_unlock_irqrestore(&rfkill->lock, flags);
518 
519 	if (!rfkill->registered)
520 		return blocked;
521 
522 	if (prev != blocked && !hwblock)
523 		schedule_work(&rfkill->uevent_work);
524 
525 	rfkill_led_trigger_event(rfkill);
526 
527 	return blocked;
528 }
529 EXPORT_SYMBOL(rfkill_set_sw_state);
530 
531 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
532 {
533 	unsigned long flags;
534 
535 	BUG_ON(!rfkill);
536 	BUG_ON(rfkill->registered);
537 
538 	spin_lock_irqsave(&rfkill->lock, flags);
539 	__rfkill_set_sw_state(rfkill, blocked);
540 	rfkill->persistent = true;
541 	spin_unlock_irqrestore(&rfkill->lock, flags);
542 }
543 EXPORT_SYMBOL(rfkill_init_sw_state);
544 
545 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
546 {
547 	unsigned long flags;
548 	bool swprev, hwprev;
549 
550 	BUG_ON(!rfkill);
551 
552 	spin_lock_irqsave(&rfkill->lock, flags);
553 
554 	/*
555 	 * No need to care about prev/setblock ... this is for uevent only
556 	 * and that will get triggered by rfkill_set_block anyway.
557 	 */
558 	swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
559 	hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
560 	__rfkill_set_sw_state(rfkill, sw);
561 	if (hw)
562 		rfkill->state |= RFKILL_BLOCK_HW;
563 	else
564 		rfkill->state &= ~RFKILL_BLOCK_HW;
565 
566 	spin_unlock_irqrestore(&rfkill->lock, flags);
567 
568 	if (!rfkill->registered) {
569 		rfkill->persistent = true;
570 	} else {
571 		if (swprev != sw || hwprev != hw)
572 			schedule_work(&rfkill->uevent_work);
573 
574 		rfkill_led_trigger_event(rfkill);
575 	}
576 }
577 EXPORT_SYMBOL(rfkill_set_states);
578 
579 static const char * const rfkill_types[] = {
580 	NULL, /* RFKILL_TYPE_ALL */
581 	"wlan",
582 	"bluetooth",
583 	"ultrawideband",
584 	"wimax",
585 	"wwan",
586 	"gps",
587 	"fm",
588 	"nfc",
589 };
590 
591 enum rfkill_type rfkill_find_type(const char *name)
592 {
593 	int i;
594 
595 	BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
596 
597 	if (!name)
598 		return RFKILL_TYPE_ALL;
599 
600 	for (i = 1; i < NUM_RFKILL_TYPES; i++)
601 		if (!strcmp(name, rfkill_types[i]))
602 			return i;
603 	return RFKILL_TYPE_ALL;
604 }
605 EXPORT_SYMBOL(rfkill_find_type);
606 
607 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
608 			 char *buf)
609 {
610 	struct rfkill *rfkill = to_rfkill(dev);
611 
612 	return sprintf(buf, "%s\n", rfkill->name);
613 }
614 static DEVICE_ATTR_RO(name);
615 
616 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
617 			 char *buf)
618 {
619 	struct rfkill *rfkill = to_rfkill(dev);
620 
621 	return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
622 }
623 static DEVICE_ATTR_RO(type);
624 
625 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
626 			  char *buf)
627 {
628 	struct rfkill *rfkill = to_rfkill(dev);
629 
630 	return sprintf(buf, "%d\n", rfkill->idx);
631 }
632 static DEVICE_ATTR_RO(index);
633 
634 static ssize_t persistent_show(struct device *dev,
635 			       struct device_attribute *attr, char *buf)
636 {
637 	struct rfkill *rfkill = to_rfkill(dev);
638 
639 	return sprintf(buf, "%d\n", rfkill->persistent);
640 }
641 static DEVICE_ATTR_RO(persistent);
642 
643 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
644 			 char *buf)
645 {
646 	struct rfkill *rfkill = to_rfkill(dev);
647 
648 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
649 }
650 static DEVICE_ATTR_RO(hard);
651 
652 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
653 			 char *buf)
654 {
655 	struct rfkill *rfkill = to_rfkill(dev);
656 
657 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
658 }
659 
660 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
661 			  const char *buf, size_t count)
662 {
663 	struct rfkill *rfkill = to_rfkill(dev);
664 	unsigned long state;
665 	int err;
666 
667 	if (!capable(CAP_NET_ADMIN))
668 		return -EPERM;
669 
670 	err = kstrtoul(buf, 0, &state);
671 	if (err)
672 		return err;
673 
674 	if (state > 1 )
675 		return -EINVAL;
676 
677 	mutex_lock(&rfkill_global_mutex);
678 	rfkill_set_block(rfkill, state);
679 	mutex_unlock(&rfkill_global_mutex);
680 
681 	return count;
682 }
683 static DEVICE_ATTR_RW(soft);
684 
685 static u8 user_state_from_blocked(unsigned long state)
686 {
687 	if (state & RFKILL_BLOCK_HW)
688 		return RFKILL_USER_STATE_HARD_BLOCKED;
689 	if (state & RFKILL_BLOCK_SW)
690 		return RFKILL_USER_STATE_SOFT_BLOCKED;
691 
692 	return RFKILL_USER_STATE_UNBLOCKED;
693 }
694 
695 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
696 			  char *buf)
697 {
698 	struct rfkill *rfkill = to_rfkill(dev);
699 
700 	return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
701 }
702 
703 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
704 			   const char *buf, size_t count)
705 {
706 	struct rfkill *rfkill = to_rfkill(dev);
707 	unsigned long state;
708 	int err;
709 
710 	if (!capable(CAP_NET_ADMIN))
711 		return -EPERM;
712 
713 	err = kstrtoul(buf, 0, &state);
714 	if (err)
715 		return err;
716 
717 	if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
718 	    state != RFKILL_USER_STATE_UNBLOCKED)
719 		return -EINVAL;
720 
721 	mutex_lock(&rfkill_global_mutex);
722 	rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
723 	mutex_unlock(&rfkill_global_mutex);
724 
725 	return count;
726 }
727 static DEVICE_ATTR_RW(state);
728 
729 static struct attribute *rfkill_dev_attrs[] = {
730 	&dev_attr_name.attr,
731 	&dev_attr_type.attr,
732 	&dev_attr_index.attr,
733 	&dev_attr_persistent.attr,
734 	&dev_attr_state.attr,
735 	&dev_attr_soft.attr,
736 	&dev_attr_hard.attr,
737 	NULL,
738 };
739 ATTRIBUTE_GROUPS(rfkill_dev);
740 
741 static void rfkill_release(struct device *dev)
742 {
743 	struct rfkill *rfkill = to_rfkill(dev);
744 
745 	kfree(rfkill);
746 }
747 
748 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
749 {
750 	struct rfkill *rfkill = to_rfkill(dev);
751 	unsigned long flags;
752 	u32 state;
753 	int error;
754 
755 	error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
756 	if (error)
757 		return error;
758 	error = add_uevent_var(env, "RFKILL_TYPE=%s",
759 			       rfkill_types[rfkill->type]);
760 	if (error)
761 		return error;
762 	spin_lock_irqsave(&rfkill->lock, flags);
763 	state = rfkill->state;
764 	spin_unlock_irqrestore(&rfkill->lock, flags);
765 	error = add_uevent_var(env, "RFKILL_STATE=%d",
766 			       user_state_from_blocked(state));
767 	return error;
768 }
769 
770 void rfkill_pause_polling(struct rfkill *rfkill)
771 {
772 	BUG_ON(!rfkill);
773 
774 	if (!rfkill->ops->poll)
775 		return;
776 
777 	rfkill->polling_paused = true;
778 	cancel_delayed_work_sync(&rfkill->poll_work);
779 }
780 EXPORT_SYMBOL(rfkill_pause_polling);
781 
782 void rfkill_resume_polling(struct rfkill *rfkill)
783 {
784 	BUG_ON(!rfkill);
785 
786 	if (!rfkill->ops->poll)
787 		return;
788 
789 	rfkill->polling_paused = false;
790 
791 	if (rfkill->suspended)
792 		return;
793 
794 	queue_delayed_work(system_power_efficient_wq,
795 			   &rfkill->poll_work, 0);
796 }
797 EXPORT_SYMBOL(rfkill_resume_polling);
798 
799 #ifdef CONFIG_PM_SLEEP
800 static int rfkill_suspend(struct device *dev)
801 {
802 	struct rfkill *rfkill = to_rfkill(dev);
803 
804 	rfkill->suspended = true;
805 	cancel_delayed_work_sync(&rfkill->poll_work);
806 
807 	return 0;
808 }
809 
810 static int rfkill_resume(struct device *dev)
811 {
812 	struct rfkill *rfkill = to_rfkill(dev);
813 	bool cur;
814 
815 	rfkill->suspended = false;
816 
817 	if (!rfkill->persistent) {
818 		cur = !!(rfkill->state & RFKILL_BLOCK_SW);
819 		rfkill_set_block(rfkill, cur);
820 	}
821 
822 	if (rfkill->ops->poll && !rfkill->polling_paused)
823 		queue_delayed_work(system_power_efficient_wq,
824 				   &rfkill->poll_work, 0);
825 
826 	return 0;
827 }
828 
829 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
830 #define RFKILL_PM_OPS (&rfkill_pm_ops)
831 #else
832 #define RFKILL_PM_OPS NULL
833 #endif
834 
835 static struct class rfkill_class = {
836 	.name		= "rfkill",
837 	.dev_release	= rfkill_release,
838 	.dev_groups	= rfkill_dev_groups,
839 	.dev_uevent	= rfkill_dev_uevent,
840 	.pm		= RFKILL_PM_OPS,
841 };
842 
843 bool rfkill_blocked(struct rfkill *rfkill)
844 {
845 	unsigned long flags;
846 	u32 state;
847 
848 	spin_lock_irqsave(&rfkill->lock, flags);
849 	state = rfkill->state;
850 	spin_unlock_irqrestore(&rfkill->lock, flags);
851 
852 	return !!(state & RFKILL_BLOCK_ANY);
853 }
854 EXPORT_SYMBOL(rfkill_blocked);
855 
856 
857 struct rfkill * __must_check rfkill_alloc(const char *name,
858 					  struct device *parent,
859 					  const enum rfkill_type type,
860 					  const struct rfkill_ops *ops,
861 					  void *ops_data)
862 {
863 	struct rfkill *rfkill;
864 	struct device *dev;
865 
866 	if (WARN_ON(!ops))
867 		return NULL;
868 
869 	if (WARN_ON(!ops->set_block))
870 		return NULL;
871 
872 	if (WARN_ON(!name))
873 		return NULL;
874 
875 	if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
876 		return NULL;
877 
878 	rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
879 	if (!rfkill)
880 		return NULL;
881 
882 	spin_lock_init(&rfkill->lock);
883 	INIT_LIST_HEAD(&rfkill->node);
884 	rfkill->type = type;
885 	strcpy(rfkill->name, name);
886 	rfkill->ops = ops;
887 	rfkill->data = ops_data;
888 
889 	dev = &rfkill->dev;
890 	dev->class = &rfkill_class;
891 	dev->parent = parent;
892 	device_initialize(dev);
893 
894 	return rfkill;
895 }
896 EXPORT_SYMBOL(rfkill_alloc);
897 
898 static void rfkill_poll(struct work_struct *work)
899 {
900 	struct rfkill *rfkill;
901 
902 	rfkill = container_of(work, struct rfkill, poll_work.work);
903 
904 	/*
905 	 * Poll hardware state -- driver will use one of the
906 	 * rfkill_set{,_hw,_sw}_state functions and use its
907 	 * return value to update the current status.
908 	 */
909 	rfkill->ops->poll(rfkill, rfkill->data);
910 
911 	queue_delayed_work(system_power_efficient_wq,
912 		&rfkill->poll_work,
913 		round_jiffies_relative(POLL_INTERVAL));
914 }
915 
916 static void rfkill_uevent_work(struct work_struct *work)
917 {
918 	struct rfkill *rfkill;
919 
920 	rfkill = container_of(work, struct rfkill, uevent_work);
921 
922 	mutex_lock(&rfkill_global_mutex);
923 	rfkill_event(rfkill);
924 	mutex_unlock(&rfkill_global_mutex);
925 }
926 
927 static void rfkill_sync_work(struct work_struct *work)
928 {
929 	struct rfkill *rfkill;
930 	bool cur;
931 
932 	rfkill = container_of(work, struct rfkill, sync_work);
933 
934 	mutex_lock(&rfkill_global_mutex);
935 	cur = rfkill_global_states[rfkill->type].cur;
936 	rfkill_set_block(rfkill, cur);
937 	mutex_unlock(&rfkill_global_mutex);
938 }
939 
940 int __must_check rfkill_register(struct rfkill *rfkill)
941 {
942 	static unsigned long rfkill_no;
943 	struct device *dev = &rfkill->dev;
944 	int error;
945 
946 	BUG_ON(!rfkill);
947 
948 	mutex_lock(&rfkill_global_mutex);
949 
950 	if (rfkill->registered) {
951 		error = -EALREADY;
952 		goto unlock;
953 	}
954 
955 	rfkill->idx = rfkill_no;
956 	dev_set_name(dev, "rfkill%lu", rfkill_no);
957 	rfkill_no++;
958 
959 	list_add_tail(&rfkill->node, &rfkill_list);
960 
961 	error = device_add(dev);
962 	if (error)
963 		goto remove;
964 
965 	error = rfkill_led_trigger_register(rfkill);
966 	if (error)
967 		goto devdel;
968 
969 	rfkill->registered = true;
970 
971 	INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
972 	INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
973 	INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
974 
975 	if (rfkill->ops->poll)
976 		queue_delayed_work(system_power_efficient_wq,
977 			&rfkill->poll_work,
978 			round_jiffies_relative(POLL_INTERVAL));
979 
980 	if (!rfkill->persistent || rfkill_epo_lock_active) {
981 		schedule_work(&rfkill->sync_work);
982 	} else {
983 #ifdef CONFIG_RFKILL_INPUT
984 		bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
985 
986 		if (!atomic_read(&rfkill_input_disabled))
987 			__rfkill_switch_all(rfkill->type, soft_blocked);
988 #endif
989 	}
990 
991 	rfkill_send_events(rfkill, RFKILL_OP_ADD);
992 
993 	mutex_unlock(&rfkill_global_mutex);
994 	return 0;
995 
996  devdel:
997 	device_del(&rfkill->dev);
998  remove:
999 	list_del_init(&rfkill->node);
1000  unlock:
1001 	mutex_unlock(&rfkill_global_mutex);
1002 	return error;
1003 }
1004 EXPORT_SYMBOL(rfkill_register);
1005 
1006 void rfkill_unregister(struct rfkill *rfkill)
1007 {
1008 	BUG_ON(!rfkill);
1009 
1010 	if (rfkill->ops->poll)
1011 		cancel_delayed_work_sync(&rfkill->poll_work);
1012 
1013 	cancel_work_sync(&rfkill->uevent_work);
1014 	cancel_work_sync(&rfkill->sync_work);
1015 
1016 	rfkill->registered = false;
1017 
1018 	device_del(&rfkill->dev);
1019 
1020 	mutex_lock(&rfkill_global_mutex);
1021 	rfkill_send_events(rfkill, RFKILL_OP_DEL);
1022 	list_del_init(&rfkill->node);
1023 	mutex_unlock(&rfkill_global_mutex);
1024 
1025 	rfkill_led_trigger_unregister(rfkill);
1026 }
1027 EXPORT_SYMBOL(rfkill_unregister);
1028 
1029 void rfkill_destroy(struct rfkill *rfkill)
1030 {
1031 	if (rfkill)
1032 		put_device(&rfkill->dev);
1033 }
1034 EXPORT_SYMBOL(rfkill_destroy);
1035 
1036 static int rfkill_fop_open(struct inode *inode, struct file *file)
1037 {
1038 	struct rfkill_data *data;
1039 	struct rfkill *rfkill;
1040 	struct rfkill_int_event *ev, *tmp;
1041 
1042 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1043 	if (!data)
1044 		return -ENOMEM;
1045 
1046 	INIT_LIST_HEAD(&data->events);
1047 	mutex_init(&data->mtx);
1048 	init_waitqueue_head(&data->read_wait);
1049 
1050 	mutex_lock(&rfkill_global_mutex);
1051 	mutex_lock(&data->mtx);
1052 	/*
1053 	 * start getting events from elsewhere but hold mtx to get
1054 	 * startup events added first
1055 	 */
1056 
1057 	list_for_each_entry(rfkill, &rfkill_list, node) {
1058 		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1059 		if (!ev)
1060 			goto free;
1061 		rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1062 		list_add_tail(&ev->list, &data->events);
1063 	}
1064 	list_add(&data->list, &rfkill_fds);
1065 	mutex_unlock(&data->mtx);
1066 	mutex_unlock(&rfkill_global_mutex);
1067 
1068 	file->private_data = data;
1069 
1070 	return nonseekable_open(inode, file);
1071 
1072  free:
1073 	mutex_unlock(&data->mtx);
1074 	mutex_unlock(&rfkill_global_mutex);
1075 	mutex_destroy(&data->mtx);
1076 	list_for_each_entry_safe(ev, tmp, &data->events, list)
1077 		kfree(ev);
1078 	kfree(data);
1079 	return -ENOMEM;
1080 }
1081 
1082 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1083 {
1084 	struct rfkill_data *data = file->private_data;
1085 	unsigned int res = POLLOUT | POLLWRNORM;
1086 
1087 	poll_wait(file, &data->read_wait, wait);
1088 
1089 	mutex_lock(&data->mtx);
1090 	if (!list_empty(&data->events))
1091 		res = POLLIN | POLLRDNORM;
1092 	mutex_unlock(&data->mtx);
1093 
1094 	return res;
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 		/* since we re-check and it just compares pointers,
1114 		 * using !list_empty() without locking isn't a problem
1115 		 */
1116 		ret = wait_event_interruptible(data->read_wait,
1117 					       !list_empty(&data->events));
1118 		mutex_lock(&data->mtx);
1119 
1120 		if (ret)
1121 			goto out;
1122 	}
1123 
1124 	ev = list_first_entry(&data->events, struct rfkill_int_event,
1125 				list);
1126 
1127 	sz = min_t(unsigned long, sizeof(ev->ev), count);
1128 	ret = sz;
1129 	if (copy_to_user(buf, &ev->ev, sz))
1130 		ret = -EFAULT;
1131 
1132 	list_del(&ev->list);
1133 	kfree(ev);
1134  out:
1135 	mutex_unlock(&data->mtx);
1136 	return ret;
1137 }
1138 
1139 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1140 				size_t count, loff_t *pos)
1141 {
1142 	struct rfkill *rfkill;
1143 	struct rfkill_event ev;
1144 	int ret;
1145 
1146 	/* we don't need the 'hard' variable but accept it */
1147 	if (count < RFKILL_EVENT_SIZE_V1 - 1)
1148 		return -EINVAL;
1149 
1150 	/*
1151 	 * Copy as much data as we can accept into our 'ev' buffer,
1152 	 * but tell userspace how much we've copied so it can determine
1153 	 * our API version even in a write() call, if it cares.
1154 	 */
1155 	count = min(count, sizeof(ev));
1156 	if (copy_from_user(&ev, buf, count))
1157 		return -EFAULT;
1158 
1159 	if (ev.type >= NUM_RFKILL_TYPES)
1160 		return -EINVAL;
1161 
1162 	mutex_lock(&rfkill_global_mutex);
1163 
1164 	switch (ev.op) {
1165 	case RFKILL_OP_CHANGE_ALL:
1166 		rfkill_update_global_state(ev.type, ev.soft);
1167 		list_for_each_entry(rfkill, &rfkill_list, node)
1168 			if (rfkill->type == ev.type ||
1169 			    ev.type == RFKILL_TYPE_ALL)
1170 				rfkill_set_block(rfkill, ev.soft);
1171 		ret = 0;
1172 		break;
1173 	case RFKILL_OP_CHANGE:
1174 		list_for_each_entry(rfkill, &rfkill_list, node)
1175 			if (rfkill->idx == ev.idx &&
1176 			    (rfkill->type == ev.type ||
1177 			     ev.type == RFKILL_TYPE_ALL))
1178 				rfkill_set_block(rfkill, ev.soft);
1179 		ret = 0;
1180 		break;
1181 	default:
1182 		ret = -EINVAL;
1183 		break;
1184 	}
1185 
1186 	mutex_unlock(&rfkill_global_mutex);
1187 
1188 	return ret ?: count;
1189 }
1190 
1191 static int rfkill_fop_release(struct inode *inode, struct file *file)
1192 {
1193 	struct rfkill_data *data = file->private_data;
1194 	struct rfkill_int_event *ev, *tmp;
1195 
1196 	mutex_lock(&rfkill_global_mutex);
1197 	list_del(&data->list);
1198 	mutex_unlock(&rfkill_global_mutex);
1199 
1200 	mutex_destroy(&data->mtx);
1201 	list_for_each_entry_safe(ev, tmp, &data->events, list)
1202 		kfree(ev);
1203 
1204 #ifdef CONFIG_RFKILL_INPUT
1205 	if (data->input_handler)
1206 		if (atomic_dec_return(&rfkill_input_disabled) == 0)
1207 			printk(KERN_DEBUG "rfkill: input handler enabled\n");
1208 #endif
1209 
1210 	kfree(data);
1211 
1212 	return 0;
1213 }
1214 
1215 #ifdef CONFIG_RFKILL_INPUT
1216 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1217 			     unsigned long arg)
1218 {
1219 	struct rfkill_data *data = file->private_data;
1220 
1221 	if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1222 		return -ENOSYS;
1223 
1224 	if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1225 		return -ENOSYS;
1226 
1227 	mutex_lock(&data->mtx);
1228 
1229 	if (!data->input_handler) {
1230 		if (atomic_inc_return(&rfkill_input_disabled) == 1)
1231 			printk(KERN_DEBUG "rfkill: input handler disabled\n");
1232 		data->input_handler = true;
1233 	}
1234 
1235 	mutex_unlock(&data->mtx);
1236 
1237 	return 0;
1238 }
1239 #endif
1240 
1241 static const struct file_operations rfkill_fops = {
1242 	.owner		= THIS_MODULE,
1243 	.open		= rfkill_fop_open,
1244 	.read		= rfkill_fop_read,
1245 	.write		= rfkill_fop_write,
1246 	.poll		= rfkill_fop_poll,
1247 	.release	= rfkill_fop_release,
1248 #ifdef CONFIG_RFKILL_INPUT
1249 	.unlocked_ioctl	= rfkill_fop_ioctl,
1250 	.compat_ioctl	= rfkill_fop_ioctl,
1251 #endif
1252 	.llseek		= no_llseek,
1253 };
1254 
1255 static struct miscdevice rfkill_miscdev = {
1256 	.name	= "rfkill",
1257 	.fops	= &rfkill_fops,
1258 	.minor	= MISC_DYNAMIC_MINOR,
1259 };
1260 
1261 static int __init rfkill_init(void)
1262 {
1263 	int error;
1264 
1265 	rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1266 
1267 	error = class_register(&rfkill_class);
1268 	if (error)
1269 		goto out;
1270 
1271 	error = misc_register(&rfkill_miscdev);
1272 	if (error) {
1273 		class_unregister(&rfkill_class);
1274 		goto out;
1275 	}
1276 
1277 #ifdef CONFIG_RFKILL_INPUT
1278 	error = rfkill_handler_init();
1279 	if (error) {
1280 		misc_deregister(&rfkill_miscdev);
1281 		class_unregister(&rfkill_class);
1282 		goto out;
1283 	}
1284 #endif
1285 
1286  out:
1287 	return error;
1288 }
1289 subsys_initcall(rfkill_init);
1290 
1291 static void __exit rfkill_exit(void)
1292 {
1293 #ifdef CONFIG_RFKILL_INPUT
1294 	rfkill_handler_exit();
1295 #endif
1296 	misc_deregister(&rfkill_miscdev);
1297 	class_unregister(&rfkill_class);
1298 }
1299 module_exit(rfkill_exit);
1300