xref: /linux-6.15/net/rfkill/core.c (revision edc7616c)
1 /*
2  * Copyright (C) 2006 - 2007 Ivo van Doorn
3  * Copyright (C) 2007 Dmitry Torokhov
4  * Copyright 2009 Johannes Berg <[email protected]>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the
18  * Free Software Foundation, Inc.,
19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/workqueue.h>
26 #include <linux/capability.h>
27 #include <linux/list.h>
28 #include <linux/mutex.h>
29 #include <linux/rfkill.h>
30 #include <linux/sched.h>
31 #include <linux/spinlock.h>
32 #include <linux/miscdevice.h>
33 #include <linux/wait.h>
34 #include <linux/poll.h>
35 #include <linux/fs.h>
36 
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 <[email protected]>");
94 MODULE_AUTHOR("Johannes Berg <[email protected]>");
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 	int err;
272 
273 	if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
274 		return;
275 
276 	/*
277 	 * Some platforms (...!) generate input events which affect the
278 	 * _hard_ kill state -- whenever something tries to change the
279 	 * current software state query the hardware state too.
280 	 */
281 	if (rfkill->ops->query)
282 		rfkill->ops->query(rfkill, rfkill->data);
283 
284 	spin_lock_irqsave(&rfkill->lock, flags);
285 	if (rfkill->state & RFKILL_BLOCK_SW)
286 		rfkill->state |= RFKILL_BLOCK_SW_PREV;
287 	else
288 		rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
289 
290 	if (blocked)
291 		rfkill->state |= RFKILL_BLOCK_SW;
292 	else
293 		rfkill->state &= ~RFKILL_BLOCK_SW;
294 
295 	rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
296 	spin_unlock_irqrestore(&rfkill->lock, flags);
297 
298 	err = rfkill->ops->set_block(rfkill->data, blocked);
299 
300 	spin_lock_irqsave(&rfkill->lock, flags);
301 	if (err) {
302 		/*
303 		 * Failed -- reset status to _prev, this may be different
304 		 * from what set set _PREV to earlier in this function
305 		 * if rfkill_set_sw_state was invoked.
306 		 */
307 		if (rfkill->state & RFKILL_BLOCK_SW_PREV)
308 			rfkill->state |= RFKILL_BLOCK_SW;
309 		else
310 			rfkill->state &= ~RFKILL_BLOCK_SW;
311 	}
312 	rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
313 	rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
314 	spin_unlock_irqrestore(&rfkill->lock, flags);
315 
316 	rfkill_led_trigger_event(rfkill);
317 	rfkill_event(rfkill);
318 }
319 
320 #ifdef CONFIG_RFKILL_INPUT
321 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
322 
323 /**
324  * __rfkill_switch_all - Toggle state of all switches of given type
325  * @type: type of interfaces to be affected
326  * @state: the new state
327  *
328  * This function sets the state of all switches of given type,
329  * unless a specific switch is claimed by userspace (in which case,
330  * that switch is left alone) or suspended.
331  *
332  * Caller must have acquired rfkill_global_mutex.
333  */
334 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
335 {
336 	struct rfkill *rfkill;
337 
338 	rfkill_global_states[type].cur = blocked;
339 	list_for_each_entry(rfkill, &rfkill_list, node) {
340 		if (rfkill->type != type)
341 			continue;
342 
343 		rfkill_set_block(rfkill, blocked);
344 	}
345 }
346 
347 /**
348  * rfkill_switch_all - Toggle state of all switches of given type
349  * @type: type of interfaces to be affected
350  * @state: the new state
351  *
352  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
353  * Please refer to __rfkill_switch_all() for details.
354  *
355  * Does nothing if the EPO lock is active.
356  */
357 void rfkill_switch_all(enum rfkill_type type, bool blocked)
358 {
359 	if (atomic_read(&rfkill_input_disabled))
360 		return;
361 
362 	mutex_lock(&rfkill_global_mutex);
363 
364 	if (!rfkill_epo_lock_active)
365 		__rfkill_switch_all(type, blocked);
366 
367 	mutex_unlock(&rfkill_global_mutex);
368 }
369 
370 /**
371  * rfkill_epo - emergency power off all transmitters
372  *
373  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
374  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
375  *
376  * The global state before the EPO is saved and can be restored later
377  * using rfkill_restore_states().
378  */
379 void rfkill_epo(void)
380 {
381 	struct rfkill *rfkill;
382 	int i;
383 
384 	if (atomic_read(&rfkill_input_disabled))
385 		return;
386 
387 	mutex_lock(&rfkill_global_mutex);
388 
389 	rfkill_epo_lock_active = true;
390 	list_for_each_entry(rfkill, &rfkill_list, node)
391 		rfkill_set_block(rfkill, true);
392 
393 	for (i = 0; i < NUM_RFKILL_TYPES; i++) {
394 		rfkill_global_states[i].sav = rfkill_global_states[i].cur;
395 		rfkill_global_states[i].cur = true;
396 	}
397 
398 	mutex_unlock(&rfkill_global_mutex);
399 }
400 
401 /**
402  * rfkill_restore_states - restore global states
403  *
404  * Restore (and sync switches to) the global state from the
405  * states in rfkill_default_states.  This can undo the effects of
406  * a call to rfkill_epo().
407  */
408 void rfkill_restore_states(void)
409 {
410 	int i;
411 
412 	if (atomic_read(&rfkill_input_disabled))
413 		return;
414 
415 	mutex_lock(&rfkill_global_mutex);
416 
417 	rfkill_epo_lock_active = false;
418 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
419 		__rfkill_switch_all(i, rfkill_global_states[i].sav);
420 	mutex_unlock(&rfkill_global_mutex);
421 }
422 
423 /**
424  * rfkill_remove_epo_lock - unlock state changes
425  *
426  * Used by rfkill-input manually unlock state changes, when
427  * the EPO switch is deactivated.
428  */
429 void rfkill_remove_epo_lock(void)
430 {
431 	if (atomic_read(&rfkill_input_disabled))
432 		return;
433 
434 	mutex_lock(&rfkill_global_mutex);
435 	rfkill_epo_lock_active = false;
436 	mutex_unlock(&rfkill_global_mutex);
437 }
438 
439 /**
440  * rfkill_is_epo_lock_active - returns true EPO is active
441  *
442  * Returns 0 (false) if there is NOT an active EPO contidion,
443  * and 1 (true) if there is an active EPO contition, which
444  * locks all radios in one of the BLOCKED states.
445  *
446  * Can be called in atomic context.
447  */
448 bool rfkill_is_epo_lock_active(void)
449 {
450 	return rfkill_epo_lock_active;
451 }
452 
453 /**
454  * rfkill_get_global_sw_state - returns global state for a type
455  * @type: the type to get the global state of
456  *
457  * Returns the current global state for a given wireless
458  * device type.
459  */
460 bool rfkill_get_global_sw_state(const enum rfkill_type type)
461 {
462 	return rfkill_global_states[type].cur;
463 }
464 #endif
465 
466 
467 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
468 {
469 	bool ret, change;
470 
471 	ret = __rfkill_set_hw_state(rfkill, blocked, &change);
472 
473 	if (!rfkill->registered)
474 		return ret;
475 
476 	if (change)
477 		schedule_work(&rfkill->uevent_work);
478 
479 	return ret;
480 }
481 EXPORT_SYMBOL(rfkill_set_hw_state);
482 
483 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
484 {
485 	u32 bit = RFKILL_BLOCK_SW;
486 
487 	/* if in a ops->set_block right now, use other bit */
488 	if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
489 		bit = RFKILL_BLOCK_SW_PREV;
490 
491 	if (blocked)
492 		rfkill->state |= bit;
493 	else
494 		rfkill->state &= ~bit;
495 }
496 
497 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
498 {
499 	unsigned long flags;
500 	bool prev, hwblock;
501 
502 	BUG_ON(!rfkill);
503 
504 	spin_lock_irqsave(&rfkill->lock, flags);
505 	prev = !!(rfkill->state & RFKILL_BLOCK_SW);
506 	__rfkill_set_sw_state(rfkill, blocked);
507 	hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
508 	blocked = blocked || hwblock;
509 	spin_unlock_irqrestore(&rfkill->lock, flags);
510 
511 	if (!rfkill->registered)
512 		return blocked;
513 
514 	if (prev != blocked && !hwblock)
515 		schedule_work(&rfkill->uevent_work);
516 
517 	rfkill_led_trigger_event(rfkill);
518 
519 	return blocked;
520 }
521 EXPORT_SYMBOL(rfkill_set_sw_state);
522 
523 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
524 {
525 	unsigned long flags;
526 
527 	BUG_ON(!rfkill);
528 	BUG_ON(rfkill->registered);
529 
530 	spin_lock_irqsave(&rfkill->lock, flags);
531 	__rfkill_set_sw_state(rfkill, blocked);
532 	rfkill->persistent = true;
533 	spin_unlock_irqrestore(&rfkill->lock, flags);
534 }
535 EXPORT_SYMBOL(rfkill_init_sw_state);
536 
537 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
538 {
539 	unsigned long flags;
540 	bool swprev, hwprev;
541 
542 	BUG_ON(!rfkill);
543 
544 	spin_lock_irqsave(&rfkill->lock, flags);
545 
546 	/*
547 	 * No need to care about prev/setblock ... this is for uevent only
548 	 * and that will get triggered by rfkill_set_block anyway.
549 	 */
550 	swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
551 	hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
552 	__rfkill_set_sw_state(rfkill, sw);
553 	if (hw)
554 		rfkill->state |= RFKILL_BLOCK_HW;
555 	else
556 		rfkill->state &= ~RFKILL_BLOCK_HW;
557 
558 	spin_unlock_irqrestore(&rfkill->lock, flags);
559 
560 	if (!rfkill->registered) {
561 		rfkill->persistent = true;
562 	} else {
563 		if (swprev != sw || hwprev != hw)
564 			schedule_work(&rfkill->uevent_work);
565 
566 		rfkill_led_trigger_event(rfkill);
567 	}
568 }
569 EXPORT_SYMBOL(rfkill_set_states);
570 
571 static ssize_t rfkill_name_show(struct device *dev,
572 				struct device_attribute *attr,
573 				char *buf)
574 {
575 	struct rfkill *rfkill = to_rfkill(dev);
576 
577 	return sprintf(buf, "%s\n", rfkill->name);
578 }
579 
580 static const char *rfkill_get_type_str(enum rfkill_type type)
581 {
582 	BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_FM + 1);
583 
584 	switch (type) {
585 	case RFKILL_TYPE_WLAN:
586 		return "wlan";
587 	case RFKILL_TYPE_BLUETOOTH:
588 		return "bluetooth";
589 	case RFKILL_TYPE_UWB:
590 		return "ultrawideband";
591 	case RFKILL_TYPE_WIMAX:
592 		return "wimax";
593 	case RFKILL_TYPE_WWAN:
594 		return "wwan";
595 	case RFKILL_TYPE_GPS:
596 		return "gps";
597 	case RFKILL_TYPE_FM:
598 		return "fm";
599 	default:
600 		BUG();
601 	}
602 }
603 
604 static ssize_t rfkill_type_show(struct device *dev,
605 				struct device_attribute *attr,
606 				char *buf)
607 {
608 	struct rfkill *rfkill = to_rfkill(dev);
609 
610 	return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
611 }
612 
613 static ssize_t rfkill_idx_show(struct device *dev,
614 			       struct device_attribute *attr,
615 			       char *buf)
616 {
617 	struct rfkill *rfkill = to_rfkill(dev);
618 
619 	return sprintf(buf, "%d\n", rfkill->idx);
620 }
621 
622 static ssize_t rfkill_persistent_show(struct device *dev,
623 			       struct device_attribute *attr,
624 			       char *buf)
625 {
626 	struct rfkill *rfkill = to_rfkill(dev);
627 
628 	return sprintf(buf, "%d\n", rfkill->persistent);
629 }
630 
631 static ssize_t rfkill_hard_show(struct device *dev,
632 				 struct device_attribute *attr,
633 				 char *buf)
634 {
635 	struct rfkill *rfkill = to_rfkill(dev);
636 
637 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
638 }
639 
640 static ssize_t rfkill_soft_show(struct device *dev,
641 				 struct device_attribute *attr,
642 				 char *buf)
643 {
644 	struct rfkill *rfkill = to_rfkill(dev);
645 
646 	return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
647 }
648 
649 static ssize_t rfkill_soft_store(struct device *dev,
650 				  struct device_attribute *attr,
651 				  const char *buf, size_t count)
652 {
653 	struct rfkill *rfkill = to_rfkill(dev);
654 	unsigned long state;
655 	int err;
656 
657 	if (!capable(CAP_NET_ADMIN))
658 		return -EPERM;
659 
660 	err = strict_strtoul(buf, 0, &state);
661 	if (err)
662 		return err;
663 
664 	if (state > 1 )
665 		return -EINVAL;
666 
667 	mutex_lock(&rfkill_global_mutex);
668 	rfkill_set_block(rfkill, state);
669 	mutex_unlock(&rfkill_global_mutex);
670 
671 	return err ?: count;
672 }
673 
674 static u8 user_state_from_blocked(unsigned long state)
675 {
676 	if (state & RFKILL_BLOCK_HW)
677 		return RFKILL_USER_STATE_HARD_BLOCKED;
678 	if (state & RFKILL_BLOCK_SW)
679 		return RFKILL_USER_STATE_SOFT_BLOCKED;
680 
681 	return RFKILL_USER_STATE_UNBLOCKED;
682 }
683 
684 static ssize_t rfkill_state_show(struct device *dev,
685 				 struct device_attribute *attr,
686 				 char *buf)
687 {
688 	struct rfkill *rfkill = to_rfkill(dev);
689 
690 	return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
691 }
692 
693 static ssize_t rfkill_state_store(struct device *dev,
694 				  struct device_attribute *attr,
695 				  const char *buf, size_t count)
696 {
697 	struct rfkill *rfkill = to_rfkill(dev);
698 	unsigned long state;
699 	int err;
700 
701 	if (!capable(CAP_NET_ADMIN))
702 		return -EPERM;
703 
704 	err = strict_strtoul(buf, 0, &state);
705 	if (err)
706 		return err;
707 
708 	if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
709 	    state != RFKILL_USER_STATE_UNBLOCKED)
710 		return -EINVAL;
711 
712 	mutex_lock(&rfkill_global_mutex);
713 	rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
714 	mutex_unlock(&rfkill_global_mutex);
715 
716 	return err ?: count;
717 }
718 
719 static ssize_t rfkill_claim_show(struct device *dev,
720 				 struct device_attribute *attr,
721 				 char *buf)
722 {
723 	return sprintf(buf, "%d\n", 0);
724 }
725 
726 static ssize_t rfkill_claim_store(struct device *dev,
727 				  struct device_attribute *attr,
728 				  const char *buf, size_t count)
729 {
730 	return -EOPNOTSUPP;
731 }
732 
733 static struct device_attribute rfkill_dev_attrs[] = {
734 	__ATTR(name, S_IRUGO, rfkill_name_show, NULL),
735 	__ATTR(type, S_IRUGO, rfkill_type_show, NULL),
736 	__ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
737 	__ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
738 	__ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
739 	__ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
740 	__ATTR(soft, S_IRUGO|S_IWUSR, rfkill_soft_show, rfkill_soft_store),
741 	__ATTR(hard, S_IRUGO, rfkill_hard_show, NULL),
742 	__ATTR_NULL
743 };
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_attrs	= rfkill_dev_attrs,
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 	list_add(&data->list, &rfkill_fds);
1041 
1042 	list_for_each_entry(rfkill, &rfkill_list, node) {
1043 		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1044 		if (!ev)
1045 			goto free;
1046 		rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1047 		list_add_tail(&ev->list, &data->events);
1048 	}
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 };
1244 
1245 static struct miscdevice rfkill_miscdev = {
1246 	.name	= "rfkill",
1247 	.fops	= &rfkill_fops,
1248 	.minor	= MISC_DYNAMIC_MINOR,
1249 };
1250 
1251 static int __init rfkill_init(void)
1252 {
1253 	int error;
1254 	int i;
1255 
1256 	for (i = 0; i < NUM_RFKILL_TYPES; i++)
1257 		rfkill_global_states[i].cur = !rfkill_default_state;
1258 
1259 	error = class_register(&rfkill_class);
1260 	if (error)
1261 		goto out;
1262 
1263 	error = misc_register(&rfkill_miscdev);
1264 	if (error) {
1265 		class_unregister(&rfkill_class);
1266 		goto out;
1267 	}
1268 
1269 #ifdef CONFIG_RFKILL_INPUT
1270 	error = rfkill_handler_init();
1271 	if (error) {
1272 		misc_deregister(&rfkill_miscdev);
1273 		class_unregister(&rfkill_class);
1274 		goto out;
1275 	}
1276 #endif
1277 
1278  out:
1279 	return error;
1280 }
1281 subsys_initcall(rfkill_init);
1282 
1283 static void __exit rfkill_exit(void)
1284 {
1285 #ifdef CONFIG_RFKILL_INPUT
1286 	rfkill_handler_exit();
1287 #endif
1288 	misc_deregister(&rfkill_miscdev);
1289 	class_unregister(&rfkill_class);
1290 }
1291 module_exit(rfkill_exit);
1292