xref: /openbmc/linux/net/rfkill/core.c (revision 8e9356c6)
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  * @state: 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 	rfkill_global_states[type].cur = blocked;
345 	list_for_each_entry(rfkill, &rfkill_list, node) {
346 		if (rfkill->type != type && type != RFKILL_TYPE_ALL)
347 			continue;
348 
349 		rfkill_set_block(rfkill, blocked);
350 	}
351 }
352 
353 /**
354  * rfkill_switch_all - Toggle state of all switches of given type
355  * @type: type of interfaces to be affected
356  * @state: the new state
357  *
358  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
359  * Please refer to __rfkill_switch_all() for details.
360  *
361  * Does nothing if the EPO lock is active.
362  */
363 void rfkill_switch_all(enum rfkill_type type, bool blocked)
364 {
365 	if (atomic_read(&rfkill_input_disabled))
366 		return;
367 
368 	mutex_lock(&rfkill_global_mutex);
369 
370 	if (!rfkill_epo_lock_active)
371 		__rfkill_switch_all(type, blocked);
372 
373 	mutex_unlock(&rfkill_global_mutex);
374 }
375 
376 /**
377  * rfkill_epo - emergency power off all transmitters
378  *
379  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
380  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
381  *
382  * The global state before the EPO is saved and can be restored later
383  * using rfkill_restore_states().
384  */
385 void rfkill_epo(void)
386 {
387 	struct rfkill *rfkill;
388 	int i;
389 
390 	if (atomic_read(&rfkill_input_disabled))
391 		return;
392 
393 	mutex_lock(&rfkill_global_mutex);
394 
395 	rfkill_epo_lock_active = true;
396 	list_for_each_entry(rfkill, &rfkill_list, node)
397 		rfkill_set_block(rfkill, true);
398 
399 	for (i = 0; i < NUM_RFKILL_TYPES; i++) {
400 		rfkill_global_states[i].sav = rfkill_global_states[i].cur;
401 		rfkill_global_states[i].cur = true;
402 	}
403 
404 	mutex_unlock(&rfkill_global_mutex);
405 }
406 
407 /**
408  * rfkill_restore_states - restore global states
409  *
410  * Restore (and sync switches to) the global state from the
411  * states in rfkill_default_states.  This can undo the effects of
412  * a call to rfkill_epo().
413  */
414 void rfkill_restore_states(void)
415 {
416 	int i;
417 
418 	if (atomic_read(&rfkill_input_disabled))
419 		return;
420 
421 	mutex_lock(&rfkill_global_mutex);
422 
423 	rfkill_epo_lock_active = false;
424 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
425 		__rfkill_switch_all(i, rfkill_global_states[i].sav);
426 	mutex_unlock(&rfkill_global_mutex);
427 }
428 
429 /**
430  * rfkill_remove_epo_lock - unlock state changes
431  *
432  * Used by rfkill-input manually unlock state changes, when
433  * the EPO switch is deactivated.
434  */
435 void rfkill_remove_epo_lock(void)
436 {
437 	if (atomic_read(&rfkill_input_disabled))
438 		return;
439 
440 	mutex_lock(&rfkill_global_mutex);
441 	rfkill_epo_lock_active = false;
442 	mutex_unlock(&rfkill_global_mutex);
443 }
444 
445 /**
446  * rfkill_is_epo_lock_active - returns true EPO is active
447  *
448  * Returns 0 (false) if there is NOT an active EPO contidion,
449  * and 1 (true) if there is an active EPO contition, which
450  * locks all radios in one of the BLOCKED states.
451  *
452  * Can be called in atomic context.
453  */
454 bool rfkill_is_epo_lock_active(void)
455 {
456 	return rfkill_epo_lock_active;
457 }
458 
459 /**
460  * rfkill_get_global_sw_state - returns global state for a type
461  * @type: the type to get the global state of
462  *
463  * Returns the current global state for a given wireless
464  * device type.
465  */
466 bool rfkill_get_global_sw_state(const enum rfkill_type type)
467 {
468 	return rfkill_global_states[type].cur;
469 }
470 #endif
471 
472 
473 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
474 {
475 	bool ret, change;
476 
477 	ret = __rfkill_set_hw_state(rfkill, blocked, &change);
478 
479 	if (!rfkill->registered)
480 		return ret;
481 
482 	if (change)
483 		schedule_work(&rfkill->uevent_work);
484 
485 	return ret;
486 }
487 EXPORT_SYMBOL(rfkill_set_hw_state);
488 
489 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
490 {
491 	u32 bit = RFKILL_BLOCK_SW;
492 
493 	/* if in a ops->set_block right now, use other bit */
494 	if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
495 		bit = RFKILL_BLOCK_SW_PREV;
496 
497 	if (blocked)
498 		rfkill->state |= bit;
499 	else
500 		rfkill->state &= ~bit;
501 }
502 
503 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
504 {
505 	unsigned long flags;
506 	bool prev, hwblock;
507 
508 	BUG_ON(!rfkill);
509 
510 	spin_lock_irqsave(&rfkill->lock, flags);
511 	prev = !!(rfkill->state & RFKILL_BLOCK_SW);
512 	__rfkill_set_sw_state(rfkill, blocked);
513 	hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
514 	blocked = blocked || hwblock;
515 	spin_unlock_irqrestore(&rfkill->lock, flags);
516 
517 	if (!rfkill->registered)
518 		return blocked;
519 
520 	if (prev != blocked && !hwblock)
521 		schedule_work(&rfkill->uevent_work);
522 
523 	rfkill_led_trigger_event(rfkill);
524 
525 	return blocked;
526 }
527 EXPORT_SYMBOL(rfkill_set_sw_state);
528 
529 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
530 {
531 	unsigned long flags;
532 
533 	BUG_ON(!rfkill);
534 	BUG_ON(rfkill->registered);
535 
536 	spin_lock_irqsave(&rfkill->lock, flags);
537 	__rfkill_set_sw_state(rfkill, blocked);
538 	rfkill->persistent = true;
539 	spin_unlock_irqrestore(&rfkill->lock, flags);
540 }
541 EXPORT_SYMBOL(rfkill_init_sw_state);
542 
543 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
544 {
545 	unsigned long flags;
546 	bool swprev, hwprev;
547 
548 	BUG_ON(!rfkill);
549 
550 	spin_lock_irqsave(&rfkill->lock, flags);
551 
552 	/*
553 	 * No need to care about prev/setblock ... this is for uevent only
554 	 * and that will get triggered by rfkill_set_block anyway.
555 	 */
556 	swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
557 	hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
558 	__rfkill_set_sw_state(rfkill, sw);
559 	if (hw)
560 		rfkill->state |= RFKILL_BLOCK_HW;
561 	else
562 		rfkill->state &= ~RFKILL_BLOCK_HW;
563 
564 	spin_unlock_irqrestore(&rfkill->lock, flags);
565 
566 	if (!rfkill->registered) {
567 		rfkill->persistent = true;
568 	} else {
569 		if (swprev != sw || hwprev != hw)
570 			schedule_work(&rfkill->uevent_work);
571 
572 		rfkill_led_trigger_event(rfkill);
573 	}
574 }
575 EXPORT_SYMBOL(rfkill_set_states);
576 
577 static ssize_t name_show(struct device *dev, 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 static DEVICE_ATTR_RO(name);
585 
586 static const char *rfkill_get_type_str(enum rfkill_type type)
587 {
588 	BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_NFC + 1);
589 
590 	switch (type) {
591 	case RFKILL_TYPE_WLAN:
592 		return "wlan";
593 	case RFKILL_TYPE_BLUETOOTH:
594 		return "bluetooth";
595 	case RFKILL_TYPE_UWB:
596 		return "ultrawideband";
597 	case RFKILL_TYPE_WIMAX:
598 		return "wimax";
599 	case RFKILL_TYPE_WWAN:
600 		return "wwan";
601 	case RFKILL_TYPE_GPS:
602 		return "gps";
603 	case RFKILL_TYPE_FM:
604 		return "fm";
605 	case RFKILL_TYPE_NFC:
606 		return "nfc";
607 	default:
608 		BUG();
609 	}
610 }
611 
612 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
613 			 char *buf)
614 {
615 	struct rfkill *rfkill = to_rfkill(dev);
616 
617 	return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
618 }
619 static DEVICE_ATTR_RO(type);
620 
621 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
622 			  char *buf)
623 {
624 	struct rfkill *rfkill = to_rfkill(dev);
625 
626 	return sprintf(buf, "%d\n", rfkill->idx);
627 }
628 static DEVICE_ATTR_RO(index);
629 
630 static ssize_t persistent_show(struct device *dev,
631 			       struct device_attribute *attr, char *buf)
632 {
633 	struct rfkill *rfkill = to_rfkill(dev);
634 
635 	return sprintf(buf, "%d\n", rfkill->persistent);
636 }
637 static DEVICE_ATTR_RO(persistent);
638 
639 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
640 			 char *buf)
641 {
642 	struct rfkill *rfkill = to_rfkill(dev);
643 
644 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
645 }
646 static DEVICE_ATTR_RO(hard);
647 
648 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
649 			 char *buf)
650 {
651 	struct rfkill *rfkill = to_rfkill(dev);
652 
653 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
654 }
655 
656 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
657 			  const char *buf, size_t count)
658 {
659 	struct rfkill *rfkill = to_rfkill(dev);
660 	unsigned long state;
661 	int err;
662 
663 	if (!capable(CAP_NET_ADMIN))
664 		return -EPERM;
665 
666 	err = kstrtoul(buf, 0, &state);
667 	if (err)
668 		return err;
669 
670 	if (state > 1 )
671 		return -EINVAL;
672 
673 	mutex_lock(&rfkill_global_mutex);
674 	rfkill_set_block(rfkill, state);
675 	mutex_unlock(&rfkill_global_mutex);
676 
677 	return count;
678 }
679 static DEVICE_ATTR_RW(soft);
680 
681 static u8 user_state_from_blocked(unsigned long state)
682 {
683 	if (state & RFKILL_BLOCK_HW)
684 		return RFKILL_USER_STATE_HARD_BLOCKED;
685 	if (state & RFKILL_BLOCK_SW)
686 		return RFKILL_USER_STATE_SOFT_BLOCKED;
687 
688 	return RFKILL_USER_STATE_UNBLOCKED;
689 }
690 
691 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
692 			  char *buf)
693 {
694 	struct rfkill *rfkill = to_rfkill(dev);
695 
696 	return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
697 }
698 
699 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
700 			   const char *buf, size_t count)
701 {
702 	struct rfkill *rfkill = to_rfkill(dev);
703 	unsigned long state;
704 	int err;
705 
706 	if (!capable(CAP_NET_ADMIN))
707 		return -EPERM;
708 
709 	err = kstrtoul(buf, 0, &state);
710 	if (err)
711 		return err;
712 
713 	if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
714 	    state != RFKILL_USER_STATE_UNBLOCKED)
715 		return -EINVAL;
716 
717 	mutex_lock(&rfkill_global_mutex);
718 	rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
719 	mutex_unlock(&rfkill_global_mutex);
720 
721 	return count;
722 }
723 static DEVICE_ATTR_RW(state);
724 
725 static ssize_t claim_show(struct device *dev, struct device_attribute *attr,
726 			  char *buf)
727 {
728 	return sprintf(buf, "%d\n", 0);
729 }
730 static DEVICE_ATTR_RO(claim);
731 
732 static struct attribute *rfkill_dev_attrs[] = {
733 	&dev_attr_name.attr,
734 	&dev_attr_type.attr,
735 	&dev_attr_index.attr,
736 	&dev_attr_persistent.attr,
737 	&dev_attr_state.attr,
738 	&dev_attr_claim.attr,
739 	&dev_attr_soft.attr,
740 	&dev_attr_hard.attr,
741 	NULL,
742 };
743 ATTRIBUTE_GROUPS(rfkill_dev);
744 
745 static void rfkill_release(struct device *dev)
746 {
747 	struct rfkill *rfkill = to_rfkill(dev);
748 
749 	kfree(rfkill);
750 }
751 
752 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
753 {
754 	struct rfkill *rfkill = to_rfkill(dev);
755 	unsigned long flags;
756 	u32 state;
757 	int error;
758 
759 	error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
760 	if (error)
761 		return error;
762 	error = add_uevent_var(env, "RFKILL_TYPE=%s",
763 			       rfkill_get_type_str(rfkill->type));
764 	if (error)
765 		return error;
766 	spin_lock_irqsave(&rfkill->lock, flags);
767 	state = rfkill->state;
768 	spin_unlock_irqrestore(&rfkill->lock, flags);
769 	error = add_uevent_var(env, "RFKILL_STATE=%d",
770 			       user_state_from_blocked(state));
771 	return error;
772 }
773 
774 void rfkill_pause_polling(struct rfkill *rfkill)
775 {
776 	BUG_ON(!rfkill);
777 
778 	if (!rfkill->ops->poll)
779 		return;
780 
781 	cancel_delayed_work_sync(&rfkill->poll_work);
782 }
783 EXPORT_SYMBOL(rfkill_pause_polling);
784 
785 void rfkill_resume_polling(struct rfkill *rfkill)
786 {
787 	BUG_ON(!rfkill);
788 
789 	if (!rfkill->ops->poll)
790 		return;
791 
792 	schedule_work(&rfkill->poll_work.work);
793 }
794 EXPORT_SYMBOL(rfkill_resume_polling);
795 
796 static int rfkill_suspend(struct device *dev, pm_message_t state)
797 {
798 	struct rfkill *rfkill = to_rfkill(dev);
799 
800 	rfkill_pause_polling(rfkill);
801 
802 	return 0;
803 }
804 
805 static int rfkill_resume(struct device *dev)
806 {
807 	struct rfkill *rfkill = to_rfkill(dev);
808 	bool cur;
809 
810 	if (!rfkill->persistent) {
811 		cur = !!(rfkill->state & RFKILL_BLOCK_SW);
812 		rfkill_set_block(rfkill, cur);
813 	}
814 
815 	rfkill_resume_polling(rfkill);
816 
817 	return 0;
818 }
819 
820 static struct class rfkill_class = {
821 	.name		= "rfkill",
822 	.dev_release	= rfkill_release,
823 	.dev_groups	= rfkill_dev_groups,
824 	.dev_uevent	= rfkill_dev_uevent,
825 	.suspend	= rfkill_suspend,
826 	.resume		= rfkill_resume,
827 };
828 
829 bool rfkill_blocked(struct rfkill *rfkill)
830 {
831 	unsigned long flags;
832 	u32 state;
833 
834 	spin_lock_irqsave(&rfkill->lock, flags);
835 	state = rfkill->state;
836 	spin_unlock_irqrestore(&rfkill->lock, flags);
837 
838 	return !!(state & RFKILL_BLOCK_ANY);
839 }
840 EXPORT_SYMBOL(rfkill_blocked);
841 
842 
843 struct rfkill * __must_check rfkill_alloc(const char *name,
844 					  struct device *parent,
845 					  const enum rfkill_type type,
846 					  const struct rfkill_ops *ops,
847 					  void *ops_data)
848 {
849 	struct rfkill *rfkill;
850 	struct device *dev;
851 
852 	if (WARN_ON(!ops))
853 		return NULL;
854 
855 	if (WARN_ON(!ops->set_block))
856 		return NULL;
857 
858 	if (WARN_ON(!name))
859 		return NULL;
860 
861 	if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
862 		return NULL;
863 
864 	rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
865 	if (!rfkill)
866 		return NULL;
867 
868 	spin_lock_init(&rfkill->lock);
869 	INIT_LIST_HEAD(&rfkill->node);
870 	rfkill->type = type;
871 	rfkill->name = name;
872 	rfkill->ops = ops;
873 	rfkill->data = ops_data;
874 
875 	dev = &rfkill->dev;
876 	dev->class = &rfkill_class;
877 	dev->parent = parent;
878 	device_initialize(dev);
879 
880 	return rfkill;
881 }
882 EXPORT_SYMBOL(rfkill_alloc);
883 
884 static void rfkill_poll(struct work_struct *work)
885 {
886 	struct rfkill *rfkill;
887 
888 	rfkill = container_of(work, struct rfkill, poll_work.work);
889 
890 	/*
891 	 * Poll hardware state -- driver will use one of the
892 	 * rfkill_set{,_hw,_sw}_state functions and use its
893 	 * return value to update the current status.
894 	 */
895 	rfkill->ops->poll(rfkill, rfkill->data);
896 
897 	schedule_delayed_work(&rfkill->poll_work,
898 		round_jiffies_relative(POLL_INTERVAL));
899 }
900 
901 static void rfkill_uevent_work(struct work_struct *work)
902 {
903 	struct rfkill *rfkill;
904 
905 	rfkill = container_of(work, struct rfkill, uevent_work);
906 
907 	mutex_lock(&rfkill_global_mutex);
908 	rfkill_event(rfkill);
909 	mutex_unlock(&rfkill_global_mutex);
910 }
911 
912 static void rfkill_sync_work(struct work_struct *work)
913 {
914 	struct rfkill *rfkill;
915 	bool cur;
916 
917 	rfkill = container_of(work, struct rfkill, sync_work);
918 
919 	mutex_lock(&rfkill_global_mutex);
920 	cur = rfkill_global_states[rfkill->type].cur;
921 	rfkill_set_block(rfkill, cur);
922 	mutex_unlock(&rfkill_global_mutex);
923 }
924 
925 int __must_check rfkill_register(struct rfkill *rfkill)
926 {
927 	static unsigned long rfkill_no;
928 	struct device *dev = &rfkill->dev;
929 	int error;
930 
931 	BUG_ON(!rfkill);
932 
933 	mutex_lock(&rfkill_global_mutex);
934 
935 	if (rfkill->registered) {
936 		error = -EALREADY;
937 		goto unlock;
938 	}
939 
940 	rfkill->idx = rfkill_no;
941 	dev_set_name(dev, "rfkill%lu", rfkill_no);
942 	rfkill_no++;
943 
944 	list_add_tail(&rfkill->node, &rfkill_list);
945 
946 	error = device_add(dev);
947 	if (error)
948 		goto remove;
949 
950 	error = rfkill_led_trigger_register(rfkill);
951 	if (error)
952 		goto devdel;
953 
954 	rfkill->registered = true;
955 
956 	INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
957 	INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
958 	INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
959 
960 	if (rfkill->ops->poll)
961 		schedule_delayed_work(&rfkill->poll_work,
962 			round_jiffies_relative(POLL_INTERVAL));
963 
964 	if (!rfkill->persistent || rfkill_epo_lock_active) {
965 		schedule_work(&rfkill->sync_work);
966 	} else {
967 #ifdef CONFIG_RFKILL_INPUT
968 		bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
969 
970 		if (!atomic_read(&rfkill_input_disabled))
971 			__rfkill_switch_all(rfkill->type, soft_blocked);
972 #endif
973 	}
974 
975 	rfkill_send_events(rfkill, RFKILL_OP_ADD);
976 
977 	mutex_unlock(&rfkill_global_mutex);
978 	return 0;
979 
980  devdel:
981 	device_del(&rfkill->dev);
982  remove:
983 	list_del_init(&rfkill->node);
984  unlock:
985 	mutex_unlock(&rfkill_global_mutex);
986 	return error;
987 }
988 EXPORT_SYMBOL(rfkill_register);
989 
990 void rfkill_unregister(struct rfkill *rfkill)
991 {
992 	BUG_ON(!rfkill);
993 
994 	if (rfkill->ops->poll)
995 		cancel_delayed_work_sync(&rfkill->poll_work);
996 
997 	cancel_work_sync(&rfkill->uevent_work);
998 	cancel_work_sync(&rfkill->sync_work);
999 
1000 	rfkill->registered = false;
1001 
1002 	device_del(&rfkill->dev);
1003 
1004 	mutex_lock(&rfkill_global_mutex);
1005 	rfkill_send_events(rfkill, RFKILL_OP_DEL);
1006 	list_del_init(&rfkill->node);
1007 	mutex_unlock(&rfkill_global_mutex);
1008 
1009 	rfkill_led_trigger_unregister(rfkill);
1010 }
1011 EXPORT_SYMBOL(rfkill_unregister);
1012 
1013 void rfkill_destroy(struct rfkill *rfkill)
1014 {
1015 	if (rfkill)
1016 		put_device(&rfkill->dev);
1017 }
1018 EXPORT_SYMBOL(rfkill_destroy);
1019 
1020 static int rfkill_fop_open(struct inode *inode, struct file *file)
1021 {
1022 	struct rfkill_data *data;
1023 	struct rfkill *rfkill;
1024 	struct rfkill_int_event *ev, *tmp;
1025 
1026 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1027 	if (!data)
1028 		return -ENOMEM;
1029 
1030 	INIT_LIST_HEAD(&data->events);
1031 	mutex_init(&data->mtx);
1032 	init_waitqueue_head(&data->read_wait);
1033 
1034 	mutex_lock(&rfkill_global_mutex);
1035 	mutex_lock(&data->mtx);
1036 	/*
1037 	 * start getting events from elsewhere but hold mtx to get
1038 	 * startup events added first
1039 	 */
1040 
1041 	list_for_each_entry(rfkill, &rfkill_list, node) {
1042 		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1043 		if (!ev)
1044 			goto free;
1045 		rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1046 		list_add_tail(&ev->list, &data->events);
1047 	}
1048 	list_add(&data->list, &rfkill_fds);
1049 	mutex_unlock(&data->mtx);
1050 	mutex_unlock(&rfkill_global_mutex);
1051 
1052 	file->private_data = data;
1053 
1054 	return nonseekable_open(inode, file);
1055 
1056  free:
1057 	mutex_unlock(&data->mtx);
1058 	mutex_unlock(&rfkill_global_mutex);
1059 	mutex_destroy(&data->mtx);
1060 	list_for_each_entry_safe(ev, tmp, &data->events, list)
1061 		kfree(ev);
1062 	kfree(data);
1063 	return -ENOMEM;
1064 }
1065 
1066 static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
1067 {
1068 	struct rfkill_data *data = file->private_data;
1069 	unsigned int res = POLLOUT | POLLWRNORM;
1070 
1071 	poll_wait(file, &data->read_wait, wait);
1072 
1073 	mutex_lock(&data->mtx);
1074 	if (!list_empty(&data->events))
1075 		res = POLLIN | POLLRDNORM;
1076 	mutex_unlock(&data->mtx);
1077 
1078 	return res;
1079 }
1080 
1081 static bool rfkill_readable(struct rfkill_data *data)
1082 {
1083 	bool r;
1084 
1085 	mutex_lock(&data->mtx);
1086 	r = !list_empty(&data->events);
1087 	mutex_unlock(&data->mtx);
1088 
1089 	return r;
1090 }
1091 
1092 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1093 			       size_t count, loff_t *pos)
1094 {
1095 	struct rfkill_data *data = file->private_data;
1096 	struct rfkill_int_event *ev;
1097 	unsigned long sz;
1098 	int ret;
1099 
1100 	mutex_lock(&data->mtx);
1101 
1102 	while (list_empty(&data->events)) {
1103 		if (file->f_flags & O_NONBLOCK) {
1104 			ret = -EAGAIN;
1105 			goto out;
1106 		}
1107 		mutex_unlock(&data->mtx);
1108 		ret = wait_event_interruptible(data->read_wait,
1109 					       rfkill_readable(data));
1110 		mutex_lock(&data->mtx);
1111 
1112 		if (ret)
1113 			goto out;
1114 	}
1115 
1116 	ev = list_first_entry(&data->events, struct rfkill_int_event,
1117 				list);
1118 
1119 	sz = min_t(unsigned long, sizeof(ev->ev), count);
1120 	ret = sz;
1121 	if (copy_to_user(buf, &ev->ev, sz))
1122 		ret = -EFAULT;
1123 
1124 	list_del(&ev->list);
1125 	kfree(ev);
1126  out:
1127 	mutex_unlock(&data->mtx);
1128 	return ret;
1129 }
1130 
1131 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1132 				size_t count, loff_t *pos)
1133 {
1134 	struct rfkill *rfkill;
1135 	struct rfkill_event ev;
1136 
1137 	/* we don't need the 'hard' variable but accept it */
1138 	if (count < RFKILL_EVENT_SIZE_V1 - 1)
1139 		return -EINVAL;
1140 
1141 	/*
1142 	 * Copy as much data as we can accept into our 'ev' buffer,
1143 	 * but tell userspace how much we've copied so it can determine
1144 	 * our API version even in a write() call, if it cares.
1145 	 */
1146 	count = min(count, sizeof(ev));
1147 	if (copy_from_user(&ev, buf, count))
1148 		return -EFAULT;
1149 
1150 	if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
1151 		return -EINVAL;
1152 
1153 	if (ev.type >= NUM_RFKILL_TYPES)
1154 		return -EINVAL;
1155 
1156 	mutex_lock(&rfkill_global_mutex);
1157 
1158 	if (ev.op == RFKILL_OP_CHANGE_ALL) {
1159 		if (ev.type == RFKILL_TYPE_ALL) {
1160 			enum rfkill_type i;
1161 			for (i = 0; i < NUM_RFKILL_TYPES; i++)
1162 				rfkill_global_states[i].cur = ev.soft;
1163 		} else {
1164 			rfkill_global_states[ev.type].cur = ev.soft;
1165 		}
1166 	}
1167 
1168 	list_for_each_entry(rfkill, &rfkill_list, node) {
1169 		if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
1170 			continue;
1171 
1172 		if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
1173 			continue;
1174 
1175 		rfkill_set_block(rfkill, ev.soft);
1176 	}
1177 	mutex_unlock(&rfkill_global_mutex);
1178 
1179 	return count;
1180 }
1181 
1182 static int rfkill_fop_release(struct inode *inode, struct file *file)
1183 {
1184 	struct rfkill_data *data = file->private_data;
1185 	struct rfkill_int_event *ev, *tmp;
1186 
1187 	mutex_lock(&rfkill_global_mutex);
1188 	list_del(&data->list);
1189 	mutex_unlock(&rfkill_global_mutex);
1190 
1191 	mutex_destroy(&data->mtx);
1192 	list_for_each_entry_safe(ev, tmp, &data->events, list)
1193 		kfree(ev);
1194 
1195 #ifdef CONFIG_RFKILL_INPUT
1196 	if (data->input_handler)
1197 		if (atomic_dec_return(&rfkill_input_disabled) == 0)
1198 			printk(KERN_DEBUG "rfkill: input handler enabled\n");
1199 #endif
1200 
1201 	kfree(data);
1202 
1203 	return 0;
1204 }
1205 
1206 #ifdef CONFIG_RFKILL_INPUT
1207 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1208 			     unsigned long arg)
1209 {
1210 	struct rfkill_data *data = file->private_data;
1211 
1212 	if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1213 		return -ENOSYS;
1214 
1215 	if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1216 		return -ENOSYS;
1217 
1218 	mutex_lock(&data->mtx);
1219 
1220 	if (!data->input_handler) {
1221 		if (atomic_inc_return(&rfkill_input_disabled) == 1)
1222 			printk(KERN_DEBUG "rfkill: input handler disabled\n");
1223 		data->input_handler = true;
1224 	}
1225 
1226 	mutex_unlock(&data->mtx);
1227 
1228 	return 0;
1229 }
1230 #endif
1231 
1232 static const struct file_operations rfkill_fops = {
1233 	.owner		= THIS_MODULE,
1234 	.open		= rfkill_fop_open,
1235 	.read		= rfkill_fop_read,
1236 	.write		= rfkill_fop_write,
1237 	.poll		= rfkill_fop_poll,
1238 	.release	= rfkill_fop_release,
1239 #ifdef CONFIG_RFKILL_INPUT
1240 	.unlocked_ioctl	= rfkill_fop_ioctl,
1241 	.compat_ioctl	= rfkill_fop_ioctl,
1242 #endif
1243 	.llseek		= no_llseek,
1244 };
1245 
1246 static struct miscdevice rfkill_miscdev = {
1247 	.name	= "rfkill",
1248 	.fops	= &rfkill_fops,
1249 	.minor	= MISC_DYNAMIC_MINOR,
1250 };
1251 
1252 static int __init rfkill_init(void)
1253 {
1254 	int error;
1255 	int i;
1256 
1257 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
1258 		rfkill_global_states[i].cur = !rfkill_default_state;
1259 
1260 	error = class_register(&rfkill_class);
1261 	if (error)
1262 		goto out;
1263 
1264 	error = misc_register(&rfkill_miscdev);
1265 	if (error) {
1266 		class_unregister(&rfkill_class);
1267 		goto out;
1268 	}
1269 
1270 #ifdef CONFIG_RFKILL_INPUT
1271 	error = rfkill_handler_init();
1272 	if (error) {
1273 		misc_deregister(&rfkill_miscdev);
1274 		class_unregister(&rfkill_class);
1275 		goto out;
1276 	}
1277 #endif
1278 
1279  out:
1280 	return error;
1281 }
1282 subsys_initcall(rfkill_init);
1283 
1284 static void __exit rfkill_exit(void)
1285 {
1286 #ifdef CONFIG_RFKILL_INPUT
1287 	rfkill_handler_exit();
1288 #endif
1289 	misc_deregister(&rfkill_miscdev);
1290 	class_unregister(&rfkill_class);
1291 }
1292 module_exit(rfkill_exit);
1293