xref: /openbmc/linux/net/rfkill/core.c (revision 9cfc5c90)
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 	const char		*name;
53 	enum rfkill_type	type;
54 
55 	unsigned long		state;
56 
57 	u32			idx;
58 
59 	bool			registered;
60 	bool			persistent;
61 
62 	const struct rfkill_ops	*ops;
63 	void			*data;
64 
65 #ifdef CONFIG_RFKILL_LEDS
66 	struct led_trigger	led_trigger;
67 	const char		*ledtrigname;
68 #endif
69 
70 	struct device		dev;
71 	struct list_head	node;
72 
73 	struct delayed_work	poll_work;
74 	struct work_struct	uevent_work;
75 	struct work_struct	sync_work;
76 };
77 #define to_rfkill(d)	container_of(d, struct rfkill, dev)
78 
79 struct rfkill_int_event {
80 	struct list_head	list;
81 	struct rfkill_event	ev;
82 };
83 
84 struct rfkill_data {
85 	struct list_head	list;
86 	struct list_head	events;
87 	struct mutex		mtx;
88 	wait_queue_head_t	read_wait;
89 	bool			input_handler;
90 };
91 
92 
93 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
94 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
95 MODULE_DESCRIPTION("RF switch support");
96 MODULE_LICENSE("GPL");
97 
98 
99 /*
100  * The locking here should be made much smarter, we currently have
101  * a bit of a stupid situation because drivers might want to register
102  * the rfkill struct under their own lock, and take this lock during
103  * rfkill method calls -- which will cause an AB-BA deadlock situation.
104  *
105  * To fix that, we need to rework this code here to be mostly lock-free
106  * and only use the mutex for list manipulations, not to protect the
107  * various other global variables. Then we can avoid holding the mutex
108  * around driver operations, and all is happy.
109  */
110 static LIST_HEAD(rfkill_list);	/* list of registered rf switches */
111 static DEFINE_MUTEX(rfkill_global_mutex);
112 static LIST_HEAD(rfkill_fds);	/* list of open fds of /dev/rfkill */
113 
114 static unsigned int rfkill_default_state = 1;
115 module_param_named(default_state, rfkill_default_state, uint, 0444);
116 MODULE_PARM_DESC(default_state,
117 		 "Default initial state for all radio types, 0 = radio off");
118 
119 static struct {
120 	bool cur, sav;
121 } rfkill_global_states[NUM_RFKILL_TYPES];
122 
123 static bool rfkill_epo_lock_active;
124 
125 
126 #ifdef CONFIG_RFKILL_LEDS
127 static void rfkill_led_trigger_event(struct rfkill *rfkill)
128 {
129 	struct led_trigger *trigger;
130 
131 	if (!rfkill->registered)
132 		return;
133 
134 	trigger = &rfkill->led_trigger;
135 
136 	if (rfkill->state & RFKILL_BLOCK_ANY)
137 		led_trigger_event(trigger, LED_OFF);
138 	else
139 		led_trigger_event(trigger, LED_FULL);
140 }
141 
142 static void rfkill_led_trigger_activate(struct led_classdev *led)
143 {
144 	struct rfkill *rfkill;
145 
146 	rfkill = container_of(led->trigger, struct rfkill, led_trigger);
147 
148 	rfkill_led_trigger_event(rfkill);
149 }
150 
151 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
152 {
153 	return rfkill->led_trigger.name;
154 }
155 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
156 
157 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
158 {
159 	BUG_ON(!rfkill);
160 
161 	rfkill->ledtrigname = name;
162 }
163 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
164 
165 static int rfkill_led_trigger_register(struct rfkill *rfkill)
166 {
167 	rfkill->led_trigger.name = rfkill->ledtrigname
168 					? : dev_name(&rfkill->dev);
169 	rfkill->led_trigger.activate = rfkill_led_trigger_activate;
170 	return led_trigger_register(&rfkill->led_trigger);
171 }
172 
173 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
174 {
175 	led_trigger_unregister(&rfkill->led_trigger);
176 }
177 #else
178 static void rfkill_led_trigger_event(struct rfkill *rfkill)
179 {
180 }
181 
182 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
183 {
184 	return 0;
185 }
186 
187 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
188 {
189 }
190 #endif /* CONFIG_RFKILL_LEDS */
191 
192 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
193 			      enum rfkill_operation op)
194 {
195 	unsigned long flags;
196 
197 	ev->idx = rfkill->idx;
198 	ev->type = rfkill->type;
199 	ev->op = op;
200 
201 	spin_lock_irqsave(&rfkill->lock, flags);
202 	ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
203 	ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
204 					RFKILL_BLOCK_SW_PREV));
205 	spin_unlock_irqrestore(&rfkill->lock, flags);
206 }
207 
208 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
209 {
210 	struct rfkill_data *data;
211 	struct rfkill_int_event *ev;
212 
213 	list_for_each_entry(data, &rfkill_fds, list) {
214 		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
215 		if (!ev)
216 			continue;
217 		rfkill_fill_event(&ev->ev, rfkill, op);
218 		mutex_lock(&data->mtx);
219 		list_add_tail(&ev->list, &data->events);
220 		mutex_unlock(&data->mtx);
221 		wake_up_interruptible(&data->read_wait);
222 	}
223 }
224 
225 static void rfkill_event(struct rfkill *rfkill)
226 {
227 	if (!rfkill->registered)
228 		return;
229 
230 	kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
231 
232 	/* also send event to /dev/rfkill */
233 	rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
234 }
235 
236 static bool __rfkill_set_hw_state(struct rfkill *rfkill,
237 				  bool blocked, bool *change)
238 {
239 	unsigned long flags;
240 	bool prev, any;
241 
242 	BUG_ON(!rfkill);
243 
244 	spin_lock_irqsave(&rfkill->lock, flags);
245 	prev = !!(rfkill->state & RFKILL_BLOCK_HW);
246 	if (blocked)
247 		rfkill->state |= RFKILL_BLOCK_HW;
248 	else
249 		rfkill->state &= ~RFKILL_BLOCK_HW;
250 	*change = prev != blocked;
251 	any = !!(rfkill->state & RFKILL_BLOCK_ANY);
252 	spin_unlock_irqrestore(&rfkill->lock, flags);
253 
254 	rfkill_led_trigger_event(rfkill);
255 
256 	return any;
257 }
258 
259 /**
260  * rfkill_set_block - wrapper for set_block method
261  *
262  * @rfkill: the rfkill struct to use
263  * @blocked: the new software state
264  *
265  * Calls the set_block method (when applicable) and handles notifications
266  * etc. as well.
267  */
268 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
269 {
270 	unsigned long flags;
271 	bool prev, curr;
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 	prev = rfkill->state & RFKILL_BLOCK_SW;
287 
288 	if (rfkill->state & RFKILL_BLOCK_SW)
289 		rfkill->state |= RFKILL_BLOCK_SW_PREV;
290 	else
291 		rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
292 
293 	if (blocked)
294 		rfkill->state |= RFKILL_BLOCK_SW;
295 	else
296 		rfkill->state &= ~RFKILL_BLOCK_SW;
297 
298 	rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
299 	spin_unlock_irqrestore(&rfkill->lock, flags);
300 
301 	err = rfkill->ops->set_block(rfkill->data, blocked);
302 
303 	spin_lock_irqsave(&rfkill->lock, flags);
304 	if (err) {
305 		/*
306 		 * Failed -- reset status to _prev, this may be different
307 		 * from what set set _PREV to earlier in this function
308 		 * if rfkill_set_sw_state was invoked.
309 		 */
310 		if (rfkill->state & RFKILL_BLOCK_SW_PREV)
311 			rfkill->state |= RFKILL_BLOCK_SW;
312 		else
313 			rfkill->state &= ~RFKILL_BLOCK_SW;
314 	}
315 	rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
316 	rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
317 	curr = rfkill->state & RFKILL_BLOCK_SW;
318 	spin_unlock_irqrestore(&rfkill->lock, flags);
319 
320 	rfkill_led_trigger_event(rfkill);
321 
322 	if (prev != curr)
323 		rfkill_event(rfkill);
324 }
325 
326 #ifdef CONFIG_RFKILL_INPUT
327 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
328 
329 /**
330  * __rfkill_switch_all - Toggle state of all switches of given type
331  * @type: type of interfaces to be affected
332  * @blocked: the new state
333  *
334  * This function sets the state of all switches of given type,
335  * unless a specific switch is claimed by userspace (in which case,
336  * that switch is left alone) or suspended.
337  *
338  * Caller must have acquired rfkill_global_mutex.
339  */
340 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
341 {
342 	struct rfkill *rfkill;
343 
344 	if (type == RFKILL_TYPE_ALL) {
345 		int i;
346 
347 		for (i = 0; i < NUM_RFKILL_TYPES; i++)
348 			rfkill_global_states[i].cur = blocked;
349 	} else {
350 		rfkill_global_states[type].cur = blocked;
351 	}
352 
353 	list_for_each_entry(rfkill, &rfkill_list, node) {
354 		if (rfkill->type != type && type != RFKILL_TYPE_ALL)
355 			continue;
356 
357 		rfkill_set_block(rfkill, blocked);
358 	}
359 }
360 
361 /**
362  * rfkill_switch_all - Toggle state of all switches of given type
363  * @type: type of interfaces to be affected
364  * @blocked: the new state
365  *
366  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
367  * Please refer to __rfkill_switch_all() for details.
368  *
369  * Does nothing if the EPO lock is active.
370  */
371 void rfkill_switch_all(enum rfkill_type type, bool blocked)
372 {
373 	if (atomic_read(&rfkill_input_disabled))
374 		return;
375 
376 	mutex_lock(&rfkill_global_mutex);
377 
378 	if (!rfkill_epo_lock_active)
379 		__rfkill_switch_all(type, blocked);
380 
381 	mutex_unlock(&rfkill_global_mutex);
382 }
383 
384 /**
385  * rfkill_epo - emergency power off all transmitters
386  *
387  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
388  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
389  *
390  * The global state before the EPO is saved and can be restored later
391  * using rfkill_restore_states().
392  */
393 void rfkill_epo(void)
394 {
395 	struct rfkill *rfkill;
396 	int i;
397 
398 	if (atomic_read(&rfkill_input_disabled))
399 		return;
400 
401 	mutex_lock(&rfkill_global_mutex);
402 
403 	rfkill_epo_lock_active = true;
404 	list_for_each_entry(rfkill, &rfkill_list, node)
405 		rfkill_set_block(rfkill, true);
406 
407 	for (i = 0; i < NUM_RFKILL_TYPES; i++) {
408 		rfkill_global_states[i].sav = rfkill_global_states[i].cur;
409 		rfkill_global_states[i].cur = true;
410 	}
411 
412 	mutex_unlock(&rfkill_global_mutex);
413 }
414 
415 /**
416  * rfkill_restore_states - restore global states
417  *
418  * Restore (and sync switches to) the global state from the
419  * states in rfkill_default_states.  This can undo the effects of
420  * a call to rfkill_epo().
421  */
422 void rfkill_restore_states(void)
423 {
424 	int i;
425 
426 	if (atomic_read(&rfkill_input_disabled))
427 		return;
428 
429 	mutex_lock(&rfkill_global_mutex);
430 
431 	rfkill_epo_lock_active = false;
432 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
433 		__rfkill_switch_all(i, rfkill_global_states[i].sav);
434 	mutex_unlock(&rfkill_global_mutex);
435 }
436 
437 /**
438  * rfkill_remove_epo_lock - unlock state changes
439  *
440  * Used by rfkill-input manually unlock state changes, when
441  * the EPO switch is deactivated.
442  */
443 void rfkill_remove_epo_lock(void)
444 {
445 	if (atomic_read(&rfkill_input_disabled))
446 		return;
447 
448 	mutex_lock(&rfkill_global_mutex);
449 	rfkill_epo_lock_active = false;
450 	mutex_unlock(&rfkill_global_mutex);
451 }
452 
453 /**
454  * rfkill_is_epo_lock_active - returns true EPO is active
455  *
456  * Returns 0 (false) if there is NOT an active EPO contidion,
457  * and 1 (true) if there is an active EPO contition, which
458  * locks all radios in one of the BLOCKED states.
459  *
460  * Can be called in atomic context.
461  */
462 bool rfkill_is_epo_lock_active(void)
463 {
464 	return rfkill_epo_lock_active;
465 }
466 
467 /**
468  * rfkill_get_global_sw_state - returns global state for a type
469  * @type: the type to get the global state of
470  *
471  * Returns the current global state for a given wireless
472  * device type.
473  */
474 bool rfkill_get_global_sw_state(const enum rfkill_type type)
475 {
476 	return rfkill_global_states[type].cur;
477 }
478 #endif
479 
480 
481 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
482 {
483 	bool ret, change;
484 
485 	ret = __rfkill_set_hw_state(rfkill, blocked, &change);
486 
487 	if (!rfkill->registered)
488 		return ret;
489 
490 	if (change)
491 		schedule_work(&rfkill->uevent_work);
492 
493 	return ret;
494 }
495 EXPORT_SYMBOL(rfkill_set_hw_state);
496 
497 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
498 {
499 	u32 bit = RFKILL_BLOCK_SW;
500 
501 	/* if in a ops->set_block right now, use other bit */
502 	if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
503 		bit = RFKILL_BLOCK_SW_PREV;
504 
505 	if (blocked)
506 		rfkill->state |= bit;
507 	else
508 		rfkill->state &= ~bit;
509 }
510 
511 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
512 {
513 	unsigned long flags;
514 	bool prev, hwblock;
515 
516 	BUG_ON(!rfkill);
517 
518 	spin_lock_irqsave(&rfkill->lock, flags);
519 	prev = !!(rfkill->state & RFKILL_BLOCK_SW);
520 	__rfkill_set_sw_state(rfkill, blocked);
521 	hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
522 	blocked = blocked || hwblock;
523 	spin_unlock_irqrestore(&rfkill->lock, flags);
524 
525 	if (!rfkill->registered)
526 		return blocked;
527 
528 	if (prev != blocked && !hwblock)
529 		schedule_work(&rfkill->uevent_work);
530 
531 	rfkill_led_trigger_event(rfkill);
532 
533 	return blocked;
534 }
535 EXPORT_SYMBOL(rfkill_set_sw_state);
536 
537 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
538 {
539 	unsigned long flags;
540 
541 	BUG_ON(!rfkill);
542 	BUG_ON(rfkill->registered);
543 
544 	spin_lock_irqsave(&rfkill->lock, flags);
545 	__rfkill_set_sw_state(rfkill, blocked);
546 	rfkill->persistent = true;
547 	spin_unlock_irqrestore(&rfkill->lock, flags);
548 }
549 EXPORT_SYMBOL(rfkill_init_sw_state);
550 
551 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
552 {
553 	unsigned long flags;
554 	bool swprev, hwprev;
555 
556 	BUG_ON(!rfkill);
557 
558 	spin_lock_irqsave(&rfkill->lock, flags);
559 
560 	/*
561 	 * No need to care about prev/setblock ... this is for uevent only
562 	 * and that will get triggered by rfkill_set_block anyway.
563 	 */
564 	swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
565 	hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
566 	__rfkill_set_sw_state(rfkill, sw);
567 	if (hw)
568 		rfkill->state |= RFKILL_BLOCK_HW;
569 	else
570 		rfkill->state &= ~RFKILL_BLOCK_HW;
571 
572 	spin_unlock_irqrestore(&rfkill->lock, flags);
573 
574 	if (!rfkill->registered) {
575 		rfkill->persistent = true;
576 	} else {
577 		if (swprev != sw || hwprev != hw)
578 			schedule_work(&rfkill->uevent_work);
579 
580 		rfkill_led_trigger_event(rfkill);
581 	}
582 }
583 EXPORT_SYMBOL(rfkill_set_states);
584 
585 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
586 			 char *buf)
587 {
588 	struct rfkill *rfkill = to_rfkill(dev);
589 
590 	return sprintf(buf, "%s\n", rfkill->name);
591 }
592 static DEVICE_ATTR_RO(name);
593 
594 static const char *rfkill_get_type_str(enum rfkill_type type)
595 {
596 	BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_NFC + 1);
597 
598 	switch (type) {
599 	case RFKILL_TYPE_WLAN:
600 		return "wlan";
601 	case RFKILL_TYPE_BLUETOOTH:
602 		return "bluetooth";
603 	case RFKILL_TYPE_UWB:
604 		return "ultrawideband";
605 	case RFKILL_TYPE_WIMAX:
606 		return "wimax";
607 	case RFKILL_TYPE_WWAN:
608 		return "wwan";
609 	case RFKILL_TYPE_GPS:
610 		return "gps";
611 	case RFKILL_TYPE_FM:
612 		return "fm";
613 	case RFKILL_TYPE_NFC:
614 		return "nfc";
615 	default:
616 		BUG();
617 	}
618 }
619 
620 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
621 			 char *buf)
622 {
623 	struct rfkill *rfkill = to_rfkill(dev);
624 
625 	return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
626 }
627 static DEVICE_ATTR_RO(type);
628 
629 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
630 			  char *buf)
631 {
632 	struct rfkill *rfkill = to_rfkill(dev);
633 
634 	return sprintf(buf, "%d\n", rfkill->idx);
635 }
636 static DEVICE_ATTR_RO(index);
637 
638 static ssize_t persistent_show(struct device *dev,
639 			       struct device_attribute *attr, char *buf)
640 {
641 	struct rfkill *rfkill = to_rfkill(dev);
642 
643 	return sprintf(buf, "%d\n", rfkill->persistent);
644 }
645 static DEVICE_ATTR_RO(persistent);
646 
647 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
648 			 char *buf)
649 {
650 	struct rfkill *rfkill = to_rfkill(dev);
651 
652 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
653 }
654 static DEVICE_ATTR_RO(hard);
655 
656 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
657 			 char *buf)
658 {
659 	struct rfkill *rfkill = to_rfkill(dev);
660 
661 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
662 }
663 
664 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
665 			  const char *buf, size_t count)
666 {
667 	struct rfkill *rfkill = to_rfkill(dev);
668 	unsigned long state;
669 	int err;
670 
671 	if (!capable(CAP_NET_ADMIN))
672 		return -EPERM;
673 
674 	err = kstrtoul(buf, 0, &state);
675 	if (err)
676 		return err;
677 
678 	if (state > 1 )
679 		return -EINVAL;
680 
681 	mutex_lock(&rfkill_global_mutex);
682 	rfkill_set_block(rfkill, state);
683 	mutex_unlock(&rfkill_global_mutex);
684 
685 	return count;
686 }
687 static DEVICE_ATTR_RW(soft);
688 
689 static u8 user_state_from_blocked(unsigned long state)
690 {
691 	if (state & RFKILL_BLOCK_HW)
692 		return RFKILL_USER_STATE_HARD_BLOCKED;
693 	if (state & RFKILL_BLOCK_SW)
694 		return RFKILL_USER_STATE_SOFT_BLOCKED;
695 
696 	return RFKILL_USER_STATE_UNBLOCKED;
697 }
698 
699 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
700 			  char *buf)
701 {
702 	struct rfkill *rfkill = to_rfkill(dev);
703 
704 	return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
705 }
706 
707 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
708 			   const char *buf, size_t count)
709 {
710 	struct rfkill *rfkill = to_rfkill(dev);
711 	unsigned long state;
712 	int err;
713 
714 	if (!capable(CAP_NET_ADMIN))
715 		return -EPERM;
716 
717 	err = kstrtoul(buf, 0, &state);
718 	if (err)
719 		return err;
720 
721 	if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
722 	    state != RFKILL_USER_STATE_UNBLOCKED)
723 		return -EINVAL;
724 
725 	mutex_lock(&rfkill_global_mutex);
726 	rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
727 	mutex_unlock(&rfkill_global_mutex);
728 
729 	return count;
730 }
731 static DEVICE_ATTR_RW(state);
732 
733 static ssize_t claim_show(struct device *dev, struct device_attribute *attr,
734 			  char *buf)
735 {
736 	return sprintf(buf, "%d\n", 0);
737 }
738 static DEVICE_ATTR_RO(claim);
739 
740 static struct attribute *rfkill_dev_attrs[] = {
741 	&dev_attr_name.attr,
742 	&dev_attr_type.attr,
743 	&dev_attr_index.attr,
744 	&dev_attr_persistent.attr,
745 	&dev_attr_state.attr,
746 	&dev_attr_claim.attr,
747 	&dev_attr_soft.attr,
748 	&dev_attr_hard.attr,
749 	NULL,
750 };
751 ATTRIBUTE_GROUPS(rfkill_dev);
752 
753 static void rfkill_release(struct device *dev)
754 {
755 	struct rfkill *rfkill = to_rfkill(dev);
756 
757 	kfree(rfkill);
758 }
759 
760 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
761 {
762 	struct rfkill *rfkill = to_rfkill(dev);
763 	unsigned long flags;
764 	u32 state;
765 	int error;
766 
767 	error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
768 	if (error)
769 		return error;
770 	error = add_uevent_var(env, "RFKILL_TYPE=%s",
771 			       rfkill_get_type_str(rfkill->type));
772 	if (error)
773 		return error;
774 	spin_lock_irqsave(&rfkill->lock, flags);
775 	state = rfkill->state;
776 	spin_unlock_irqrestore(&rfkill->lock, flags);
777 	error = add_uevent_var(env, "RFKILL_STATE=%d",
778 			       user_state_from_blocked(state));
779 	return error;
780 }
781 
782 void rfkill_pause_polling(struct rfkill *rfkill)
783 {
784 	BUG_ON(!rfkill);
785 
786 	if (!rfkill->ops->poll)
787 		return;
788 
789 	cancel_delayed_work_sync(&rfkill->poll_work);
790 }
791 EXPORT_SYMBOL(rfkill_pause_polling);
792 
793 void rfkill_resume_polling(struct rfkill *rfkill)
794 {
795 	BUG_ON(!rfkill);
796 
797 	if (!rfkill->ops->poll)
798 		return;
799 
800 	queue_delayed_work(system_power_efficient_wq,
801 			   &rfkill->poll_work, 0);
802 }
803 EXPORT_SYMBOL(rfkill_resume_polling);
804 
805 #ifdef CONFIG_PM_SLEEP
806 static int rfkill_suspend(struct device *dev)
807 {
808 	struct rfkill *rfkill = to_rfkill(dev);
809 
810 	rfkill_pause_polling(rfkill);
811 
812 	return 0;
813 }
814 
815 static int rfkill_resume(struct device *dev)
816 {
817 	struct rfkill *rfkill = to_rfkill(dev);
818 	bool cur;
819 
820 	if (!rfkill->persistent) {
821 		cur = !!(rfkill->state & RFKILL_BLOCK_SW);
822 		rfkill_set_block(rfkill, cur);
823 	}
824 
825 	rfkill_resume_polling(rfkill);
826 
827 	return 0;
828 }
829 
830 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
831 #define RFKILL_PM_OPS (&rfkill_pm_ops)
832 #else
833 #define RFKILL_PM_OPS NULL
834 #endif
835 
836 static struct class rfkill_class = {
837 	.name		= "rfkill",
838 	.dev_release	= rfkill_release,
839 	.dev_groups	= rfkill_dev_groups,
840 	.dev_uevent	= rfkill_dev_uevent,
841 	.pm		= RFKILL_PM_OPS,
842 };
843 
844 bool rfkill_blocked(struct rfkill *rfkill)
845 {
846 	unsigned long flags;
847 	u32 state;
848 
849 	spin_lock_irqsave(&rfkill->lock, flags);
850 	state = rfkill->state;
851 	spin_unlock_irqrestore(&rfkill->lock, flags);
852 
853 	return !!(state & RFKILL_BLOCK_ANY);
854 }
855 EXPORT_SYMBOL(rfkill_blocked);
856 
857 
858 struct rfkill * __must_check rfkill_alloc(const char *name,
859 					  struct device *parent,
860 					  const enum rfkill_type type,
861 					  const struct rfkill_ops *ops,
862 					  void *ops_data)
863 {
864 	struct rfkill *rfkill;
865 	struct device *dev;
866 
867 	if (WARN_ON(!ops))
868 		return NULL;
869 
870 	if (WARN_ON(!ops->set_block))
871 		return NULL;
872 
873 	if (WARN_ON(!name))
874 		return NULL;
875 
876 	if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
877 		return NULL;
878 
879 	rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
880 	if (!rfkill)
881 		return NULL;
882 
883 	spin_lock_init(&rfkill->lock);
884 	INIT_LIST_HEAD(&rfkill->node);
885 	rfkill->type = type;
886 	rfkill->name = name;
887 	rfkill->ops = ops;
888 	rfkill->data = ops_data;
889 
890 	dev = &rfkill->dev;
891 	dev->class = &rfkill_class;
892 	dev->parent = parent;
893 	device_initialize(dev);
894 
895 	return rfkill;
896 }
897 EXPORT_SYMBOL(rfkill_alloc);
898 
899 static void rfkill_poll(struct work_struct *work)
900 {
901 	struct rfkill *rfkill;
902 
903 	rfkill = container_of(work, struct rfkill, poll_work.work);
904 
905 	/*
906 	 * Poll hardware state -- driver will use one of the
907 	 * rfkill_set{,_hw,_sw}_state functions and use its
908 	 * return value to update the current status.
909 	 */
910 	rfkill->ops->poll(rfkill, rfkill->data);
911 
912 	queue_delayed_work(system_power_efficient_wq,
913 		&rfkill->poll_work,
914 		round_jiffies_relative(POLL_INTERVAL));
915 }
916 
917 static void rfkill_uevent_work(struct work_struct *work)
918 {
919 	struct rfkill *rfkill;
920 
921 	rfkill = container_of(work, struct rfkill, uevent_work);
922 
923 	mutex_lock(&rfkill_global_mutex);
924 	rfkill_event(rfkill);
925 	mutex_unlock(&rfkill_global_mutex);
926 }
927 
928 static void rfkill_sync_work(struct work_struct *work)
929 {
930 	struct rfkill *rfkill;
931 	bool cur;
932 
933 	rfkill = container_of(work, struct rfkill, sync_work);
934 
935 	mutex_lock(&rfkill_global_mutex);
936 	cur = rfkill_global_states[rfkill->type].cur;
937 	rfkill_set_block(rfkill, cur);
938 	mutex_unlock(&rfkill_global_mutex);
939 }
940 
941 int __must_check rfkill_register(struct rfkill *rfkill)
942 {
943 	static unsigned long rfkill_no;
944 	struct device *dev = &rfkill->dev;
945 	int error;
946 
947 	BUG_ON(!rfkill);
948 
949 	mutex_lock(&rfkill_global_mutex);
950 
951 	if (rfkill->registered) {
952 		error = -EALREADY;
953 		goto unlock;
954 	}
955 
956 	rfkill->idx = rfkill_no;
957 	dev_set_name(dev, "rfkill%lu", rfkill_no);
958 	rfkill_no++;
959 
960 	list_add_tail(&rfkill->node, &rfkill_list);
961 
962 	error = device_add(dev);
963 	if (error)
964 		goto remove;
965 
966 	error = rfkill_led_trigger_register(rfkill);
967 	if (error)
968 		goto devdel;
969 
970 	rfkill->registered = true;
971 
972 	INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
973 	INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
974 	INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
975 
976 	if (rfkill->ops->poll)
977 		queue_delayed_work(system_power_efficient_wq,
978 			&rfkill->poll_work,
979 			round_jiffies_relative(POLL_INTERVAL));
980 
981 	if (!rfkill->persistent || rfkill_epo_lock_active) {
982 		schedule_work(&rfkill->sync_work);
983 	} else {
984 #ifdef CONFIG_RFKILL_INPUT
985 		bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
986 
987 		if (!atomic_read(&rfkill_input_disabled))
988 			__rfkill_switch_all(rfkill->type, soft_blocked);
989 #endif
990 	}
991 
992 	rfkill_send_events(rfkill, RFKILL_OP_ADD);
993 
994 	mutex_unlock(&rfkill_global_mutex);
995 	return 0;
996 
997  devdel:
998 	device_del(&rfkill->dev);
999  remove:
1000 	list_del_init(&rfkill->node);
1001  unlock:
1002 	mutex_unlock(&rfkill_global_mutex);
1003 	return error;
1004 }
1005 EXPORT_SYMBOL(rfkill_register);
1006 
1007 void rfkill_unregister(struct rfkill *rfkill)
1008 {
1009 	BUG_ON(!rfkill);
1010 
1011 	if (rfkill->ops->poll)
1012 		cancel_delayed_work_sync(&rfkill->poll_work);
1013 
1014 	cancel_work_sync(&rfkill->uevent_work);
1015 	cancel_work_sync(&rfkill->sync_work);
1016 
1017 	rfkill->registered = false;
1018 
1019 	device_del(&rfkill->dev);
1020 
1021 	mutex_lock(&rfkill_global_mutex);
1022 	rfkill_send_events(rfkill, RFKILL_OP_DEL);
1023 	list_del_init(&rfkill->node);
1024 	mutex_unlock(&rfkill_global_mutex);
1025 
1026 	rfkill_led_trigger_unregister(rfkill);
1027 }
1028 EXPORT_SYMBOL(rfkill_unregister);
1029 
1030 void rfkill_destroy(struct rfkill *rfkill)
1031 {
1032 	if (rfkill)
1033 		put_device(&rfkill->dev);
1034 }
1035 EXPORT_SYMBOL(rfkill_destroy);
1036 
1037 static int rfkill_fop_open(struct inode *inode, struct file *file)
1038 {
1039 	struct rfkill_data *data;
1040 	struct rfkill *rfkill;
1041 	struct rfkill_int_event *ev, *tmp;
1042 
1043 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1044 	if (!data)
1045 		return -ENOMEM;
1046 
1047 	INIT_LIST_HEAD(&data->events);
1048 	mutex_init(&data->mtx);
1049 	init_waitqueue_head(&data->read_wait);
1050 
1051 	mutex_lock(&rfkill_global_mutex);
1052 	mutex_lock(&data->mtx);
1053 	/*
1054 	 * start getting events from elsewhere but hold mtx to get
1055 	 * startup events added first
1056 	 */
1057 
1058 	list_for_each_entry(rfkill, &rfkill_list, node) {
1059 		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1060 		if (!ev)
1061 			goto free;
1062 		rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1063 		list_add_tail(&ev->list, &data->events);
1064 	}
1065 	list_add(&data->list, &rfkill_fds);
1066 	mutex_unlock(&data->mtx);
1067 	mutex_unlock(&rfkill_global_mutex);
1068 
1069 	file->private_data = data;
1070 
1071 	return nonseekable_open(inode, file);
1072 
1073  free:
1074 	mutex_unlock(&data->mtx);
1075 	mutex_unlock(&rfkill_global_mutex);
1076 	mutex_destroy(&data->mtx);
1077 	list_for_each_entry_safe(ev, tmp, &data->events, list)
1078 		kfree(ev);
1079 	kfree(data);
1080 	return -ENOMEM;
1081 }
1082 
1083 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1084 {
1085 	struct rfkill_data *data = file->private_data;
1086 	unsigned int res = POLLOUT | POLLWRNORM;
1087 
1088 	poll_wait(file, &data->read_wait, wait);
1089 
1090 	mutex_lock(&data->mtx);
1091 	if (!list_empty(&data->events))
1092 		res = POLLIN | POLLRDNORM;
1093 	mutex_unlock(&data->mtx);
1094 
1095 	return res;
1096 }
1097 
1098 static bool rfkill_readable(struct rfkill_data *data)
1099 {
1100 	bool r;
1101 
1102 	mutex_lock(&data->mtx);
1103 	r = !list_empty(&data->events);
1104 	mutex_unlock(&data->mtx);
1105 
1106 	return r;
1107 }
1108 
1109 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1110 			       size_t count, loff_t *pos)
1111 {
1112 	struct rfkill_data *data = file->private_data;
1113 	struct rfkill_int_event *ev;
1114 	unsigned long sz;
1115 	int ret;
1116 
1117 	mutex_lock(&data->mtx);
1118 
1119 	while (list_empty(&data->events)) {
1120 		if (file->f_flags & O_NONBLOCK) {
1121 			ret = -EAGAIN;
1122 			goto out;
1123 		}
1124 		mutex_unlock(&data->mtx);
1125 		ret = wait_event_interruptible(data->read_wait,
1126 					       rfkill_readable(data));
1127 		mutex_lock(&data->mtx);
1128 
1129 		if (ret)
1130 			goto out;
1131 	}
1132 
1133 	ev = list_first_entry(&data->events, struct rfkill_int_event,
1134 				list);
1135 
1136 	sz = min_t(unsigned long, sizeof(ev->ev), count);
1137 	ret = sz;
1138 	if (copy_to_user(buf, &ev->ev, sz))
1139 		ret = -EFAULT;
1140 
1141 	list_del(&ev->list);
1142 	kfree(ev);
1143  out:
1144 	mutex_unlock(&data->mtx);
1145 	return ret;
1146 }
1147 
1148 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1149 				size_t count, loff_t *pos)
1150 {
1151 	struct rfkill *rfkill;
1152 	struct rfkill_event ev;
1153 
1154 	/* we don't need the 'hard' variable but accept it */
1155 	if (count < RFKILL_EVENT_SIZE_V1 - 1)
1156 		return -EINVAL;
1157 
1158 	/*
1159 	 * Copy as much data as we can accept into our 'ev' buffer,
1160 	 * but tell userspace how much we've copied so it can determine
1161 	 * our API version even in a write() call, if it cares.
1162 	 */
1163 	count = min(count, sizeof(ev));
1164 	if (copy_from_user(&ev, buf, count))
1165 		return -EFAULT;
1166 
1167 	if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1168 		return -EINVAL;
1169 
1170 	if (ev.type >= NUM_RFKILL_TYPES)
1171 		return -EINVAL;
1172 
1173 	mutex_lock(&rfkill_global_mutex);
1174 
1175 	if (ev.op == RFKILL_OP_CHANGE_ALL) {
1176 		if (ev.type == RFKILL_TYPE_ALL) {
1177 			enum rfkill_type i;
1178 			for (i = 0; i < NUM_RFKILL_TYPES; i++)
1179 				rfkill_global_states[i].cur = ev.soft;
1180 		} else {
1181 			rfkill_global_states[ev.type].cur = ev.soft;
1182 		}
1183 	}
1184 
1185 	list_for_each_entry(rfkill, &rfkill_list, node) {
1186 		if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1187 			continue;
1188 
1189 		if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1190 			continue;
1191 
1192 		rfkill_set_block(rfkill, ev.soft);
1193 	}
1194 	mutex_unlock(&rfkill_global_mutex);
1195 
1196 	return count;
1197 }
1198 
1199 static int rfkill_fop_release(struct inode *inode, struct file *file)
1200 {
1201 	struct rfkill_data *data = file->private_data;
1202 	struct rfkill_int_event *ev, *tmp;
1203 
1204 	mutex_lock(&rfkill_global_mutex);
1205 	list_del(&data->list);
1206 	mutex_unlock(&rfkill_global_mutex);
1207 
1208 	mutex_destroy(&data->mtx);
1209 	list_for_each_entry_safe(ev, tmp, &data->events, list)
1210 		kfree(ev);
1211 
1212 #ifdef CONFIG_RFKILL_INPUT
1213 	if (data->input_handler)
1214 		if (atomic_dec_return(&rfkill_input_disabled) == 0)
1215 			printk(KERN_DEBUG "rfkill: input handler enabled\n");
1216 #endif
1217 
1218 	kfree(data);
1219 
1220 	return 0;
1221 }
1222 
1223 #ifdef CONFIG_RFKILL_INPUT
1224 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1225 			     unsigned long arg)
1226 {
1227 	struct rfkill_data *data = file->private_data;
1228 
1229 	if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1230 		return -ENOSYS;
1231 
1232 	if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1233 		return -ENOSYS;
1234 
1235 	mutex_lock(&data->mtx);
1236 
1237 	if (!data->input_handler) {
1238 		if (atomic_inc_return(&rfkill_input_disabled) == 1)
1239 			printk(KERN_DEBUG "rfkill: input handler disabled\n");
1240 		data->input_handler = true;
1241 	}
1242 
1243 	mutex_unlock(&data->mtx);
1244 
1245 	return 0;
1246 }
1247 #endif
1248 
1249 static const struct file_operations rfkill_fops = {
1250 	.owner		= THIS_MODULE,
1251 	.open		= rfkill_fop_open,
1252 	.read		= rfkill_fop_read,
1253 	.write		= rfkill_fop_write,
1254 	.poll		= rfkill_fop_poll,
1255 	.release	= rfkill_fop_release,
1256 #ifdef CONFIG_RFKILL_INPUT
1257 	.unlocked_ioctl	= rfkill_fop_ioctl,
1258 	.compat_ioctl	= rfkill_fop_ioctl,
1259 #endif
1260 	.llseek		= no_llseek,
1261 };
1262 
1263 static struct miscdevice rfkill_miscdev = {
1264 	.name	= "rfkill",
1265 	.fops	= &rfkill_fops,
1266 	.minor	= MISC_DYNAMIC_MINOR,
1267 };
1268 
1269 static int __init rfkill_init(void)
1270 {
1271 	int error;
1272 	int i;
1273 
1274 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
1275 		rfkill_global_states[i].cur = !rfkill_default_state;
1276 
1277 	error = class_register(&rfkill_class);
1278 	if (error)
1279 		goto out;
1280 
1281 	error = misc_register(&rfkill_miscdev);
1282 	if (error) {
1283 		class_unregister(&rfkill_class);
1284 		goto out;
1285 	}
1286 
1287 #ifdef CONFIG_RFKILL_INPUT
1288 	error = rfkill_handler_init();
1289 	if (error) {
1290 		misc_deregister(&rfkill_miscdev);
1291 		class_unregister(&rfkill_class);
1292 		goto out;
1293 	}
1294 #endif
1295 
1296  out:
1297 	return error;
1298 }
1299 subsys_initcall(rfkill_init);
1300 
1301 static void __exit rfkill_exit(void)
1302 {
1303 #ifdef CONFIG_RFKILL_INPUT
1304 	rfkill_handler_exit();
1305 #endif
1306 	misc_deregister(&rfkill_miscdev);
1307 	class_unregister(&rfkill_class);
1308 }
1309 module_exit(rfkill_exit);
1310