GNU Linux-libre 4.19.242-gnu1
[releases.git] / net / rfkill / core.c
1 /*
2  * Copyright (C) 2006 - 2007 Ivo van Doorn
3  * Copyright (C) 2007 Dmitry Torokhov
4  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
18  */
19
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/workqueue.h>
24 #include <linux/capability.h>
25 #include <linux/list.h>
26 #include <linux/mutex.h>
27 #include <linux/rfkill.h>
28 #include <linux/sched.h>
29 #include <linux/spinlock.h>
30 #include <linux/device.h>
31 #include <linux/miscdevice.h>
32 #include <linux/wait.h>
33 #include <linux/poll.h>
34 #include <linux/fs.h>
35 #include <linux/slab.h>
36
37 #include "rfkill.h"
38
39 #define POLL_INTERVAL           (5 * HZ)
40
41 #define RFKILL_BLOCK_HW         BIT(0)
42 #define RFKILL_BLOCK_SW         BIT(1)
43 #define RFKILL_BLOCK_SW_PREV    BIT(2)
44 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
45                                  RFKILL_BLOCK_SW |\
46                                  RFKILL_BLOCK_SW_PREV)
47 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
48
49 struct rfkill {
50         spinlock_t              lock;
51
52         enum rfkill_type        type;
53
54         unsigned long           state;
55
56         u32                     idx;
57
58         bool                    registered;
59         bool                    persistent;
60         bool                    polling_paused;
61         bool                    suspended;
62
63         const struct rfkill_ops *ops;
64         void                    *data;
65
66 #ifdef CONFIG_RFKILL_LEDS
67         struct led_trigger      led_trigger;
68         const char              *ledtrigname;
69 #endif
70
71         struct device           dev;
72         struct list_head        node;
73
74         struct delayed_work     poll_work;
75         struct work_struct      uevent_work;
76         struct work_struct      sync_work;
77         char                    name[];
78 };
79 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
80
81 struct rfkill_int_event {
82         struct list_head        list;
83         struct rfkill_event     ev;
84 };
85
86 struct rfkill_data {
87         struct list_head        list;
88         struct list_head        events;
89         struct mutex            mtx;
90         wait_queue_head_t       read_wait;
91         bool                    input_handler;
92 };
93
94
95 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
96 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
97 MODULE_DESCRIPTION("RF switch support");
98 MODULE_LICENSE("GPL");
99
100
101 /*
102  * The locking here should be made much smarter, we currently have
103  * a bit of a stupid situation because drivers might want to register
104  * the rfkill struct under their own lock, and take this lock during
105  * rfkill method calls -- which will cause an AB-BA deadlock situation.
106  *
107  * To fix that, we need to rework this code here to be mostly lock-free
108  * and only use the mutex for list manipulations, not to protect the
109  * various other global variables. Then we can avoid holding the mutex
110  * around driver operations, and all is happy.
111  */
112 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
113 static DEFINE_MUTEX(rfkill_global_mutex);
114 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
115
116 static unsigned int rfkill_default_state = 1;
117 module_param_named(default_state, rfkill_default_state, uint, 0444);
118 MODULE_PARM_DESC(default_state,
119                  "Default initial state for all radio types, 0 = radio off");
120
121 static struct {
122         bool cur, sav;
123 } rfkill_global_states[NUM_RFKILL_TYPES];
124
125 static bool rfkill_epo_lock_active;
126
127
128 #ifdef CONFIG_RFKILL_LEDS
129 static void rfkill_led_trigger_event(struct rfkill *rfkill)
130 {
131         struct led_trigger *trigger;
132
133         if (!rfkill->registered)
134                 return;
135
136         trigger = &rfkill->led_trigger;
137
138         if (rfkill->state & RFKILL_BLOCK_ANY)
139                 led_trigger_event(trigger, LED_OFF);
140         else
141                 led_trigger_event(trigger, LED_FULL);
142 }
143
144 static int rfkill_led_trigger_activate(struct led_classdev *led)
145 {
146         struct rfkill *rfkill;
147
148         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
149
150         rfkill_led_trigger_event(rfkill);
151
152         return 0;
153 }
154
155 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
156 {
157         return rfkill->led_trigger.name;
158 }
159 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
160
161 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
162 {
163         BUG_ON(!rfkill);
164
165         rfkill->ledtrigname = name;
166 }
167 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
168
169 static int rfkill_led_trigger_register(struct rfkill *rfkill)
170 {
171         rfkill->led_trigger.name = rfkill->ledtrigname
172                                         ? : dev_name(&rfkill->dev);
173         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
174         return led_trigger_register(&rfkill->led_trigger);
175 }
176
177 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
178 {
179         led_trigger_unregister(&rfkill->led_trigger);
180 }
181
182 static struct led_trigger rfkill_any_led_trigger;
183 static struct led_trigger rfkill_none_led_trigger;
184 static struct work_struct rfkill_global_led_trigger_work;
185
186 static void rfkill_global_led_trigger_worker(struct work_struct *work)
187 {
188         enum led_brightness brightness = LED_OFF;
189         struct rfkill *rfkill;
190
191         mutex_lock(&rfkill_global_mutex);
192         list_for_each_entry(rfkill, &rfkill_list, node) {
193                 if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
194                         brightness = LED_FULL;
195                         break;
196                 }
197         }
198         mutex_unlock(&rfkill_global_mutex);
199
200         led_trigger_event(&rfkill_any_led_trigger, brightness);
201         led_trigger_event(&rfkill_none_led_trigger,
202                           brightness == LED_OFF ? LED_FULL : LED_OFF);
203 }
204
205 static void rfkill_global_led_trigger_event(void)
206 {
207         schedule_work(&rfkill_global_led_trigger_work);
208 }
209
210 static int rfkill_global_led_trigger_register(void)
211 {
212         int ret;
213
214         INIT_WORK(&rfkill_global_led_trigger_work,
215                         rfkill_global_led_trigger_worker);
216
217         rfkill_any_led_trigger.name = "rfkill-any";
218         ret = led_trigger_register(&rfkill_any_led_trigger);
219         if (ret)
220                 return ret;
221
222         rfkill_none_led_trigger.name = "rfkill-none";
223         ret = led_trigger_register(&rfkill_none_led_trigger);
224         if (ret)
225                 led_trigger_unregister(&rfkill_any_led_trigger);
226         else
227                 /* Delay activation until all global triggers are registered */
228                 rfkill_global_led_trigger_event();
229
230         return ret;
231 }
232
233 static void rfkill_global_led_trigger_unregister(void)
234 {
235         led_trigger_unregister(&rfkill_none_led_trigger);
236         led_trigger_unregister(&rfkill_any_led_trigger);
237         cancel_work_sync(&rfkill_global_led_trigger_work);
238 }
239 #else
240 static void rfkill_led_trigger_event(struct rfkill *rfkill)
241 {
242 }
243
244 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
245 {
246         return 0;
247 }
248
249 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
250 {
251 }
252
253 static void rfkill_global_led_trigger_event(void)
254 {
255 }
256
257 static int rfkill_global_led_trigger_register(void)
258 {
259         return 0;
260 }
261
262 static void rfkill_global_led_trigger_unregister(void)
263 {
264 }
265 #endif /* CONFIG_RFKILL_LEDS */
266
267 static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
268                               enum rfkill_operation op)
269 {
270         unsigned long flags;
271
272         ev->idx = rfkill->idx;
273         ev->type = rfkill->type;
274         ev->op = op;
275
276         spin_lock_irqsave(&rfkill->lock, flags);
277         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
278         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
279                                         RFKILL_BLOCK_SW_PREV));
280         spin_unlock_irqrestore(&rfkill->lock, flags);
281 }
282
283 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
284 {
285         struct rfkill_data *data;
286         struct rfkill_int_event *ev;
287
288         list_for_each_entry(data, &rfkill_fds, list) {
289                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
290                 if (!ev)
291                         continue;
292                 rfkill_fill_event(&ev->ev, rfkill, op);
293                 mutex_lock(&data->mtx);
294                 list_add_tail(&ev->list, &data->events);
295                 mutex_unlock(&data->mtx);
296                 wake_up_interruptible(&data->read_wait);
297         }
298 }
299
300 static void rfkill_event(struct rfkill *rfkill)
301 {
302         if (!rfkill->registered)
303                 return;
304
305         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
306
307         /* also send event to /dev/rfkill */
308         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
309 }
310
311 /**
312  * rfkill_set_block - wrapper for set_block method
313  *
314  * @rfkill: the rfkill struct to use
315  * @blocked: the new software state
316  *
317  * Calls the set_block method (when applicable) and handles notifications
318  * etc. as well.
319  */
320 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
321 {
322         unsigned long flags;
323         bool prev, curr;
324         int err;
325
326         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
327                 return;
328
329         /*
330          * Some platforms (...!) generate input events which affect the
331          * _hard_ kill state -- whenever something tries to change the
332          * current software state query the hardware state too.
333          */
334         if (rfkill->ops->query)
335                 rfkill->ops->query(rfkill, rfkill->data);
336
337         spin_lock_irqsave(&rfkill->lock, flags);
338         prev = rfkill->state & RFKILL_BLOCK_SW;
339
340         if (prev)
341                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
342         else
343                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
344
345         if (blocked)
346                 rfkill->state |= RFKILL_BLOCK_SW;
347         else
348                 rfkill->state &= ~RFKILL_BLOCK_SW;
349
350         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
351         spin_unlock_irqrestore(&rfkill->lock, flags);
352
353         err = rfkill->ops->set_block(rfkill->data, blocked);
354
355         spin_lock_irqsave(&rfkill->lock, flags);
356         if (err) {
357                 /*
358                  * Failed -- reset status to _PREV, which may be different
359                  * from what we have set _PREV to earlier in this function
360                  * if rfkill_set_sw_state was invoked.
361                  */
362                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
363                         rfkill->state |= RFKILL_BLOCK_SW;
364                 else
365                         rfkill->state &= ~RFKILL_BLOCK_SW;
366         }
367         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
368         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
369         curr = rfkill->state & RFKILL_BLOCK_SW;
370         spin_unlock_irqrestore(&rfkill->lock, flags);
371
372         rfkill_led_trigger_event(rfkill);
373         rfkill_global_led_trigger_event();
374
375         if (prev != curr)
376                 rfkill_event(rfkill);
377 }
378
379 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
380 {
381         int i;
382
383         if (type != RFKILL_TYPE_ALL) {
384                 rfkill_global_states[type].cur = blocked;
385                 return;
386         }
387
388         for (i = 0; i < NUM_RFKILL_TYPES; i++)
389                 rfkill_global_states[i].cur = blocked;
390 }
391
392 #ifdef CONFIG_RFKILL_INPUT
393 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
394
395 /**
396  * __rfkill_switch_all - Toggle state of all switches of given type
397  * @type: type of interfaces to be affected
398  * @blocked: the new state
399  *
400  * This function sets the state of all switches of given type,
401  * unless a specific switch is suspended.
402  *
403  * Caller must have acquired rfkill_global_mutex.
404  */
405 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
406 {
407         struct rfkill *rfkill;
408
409         rfkill_update_global_state(type, blocked);
410         list_for_each_entry(rfkill, &rfkill_list, node) {
411                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
412                         continue;
413
414                 rfkill_set_block(rfkill, blocked);
415         }
416 }
417
418 /**
419  * rfkill_switch_all - Toggle state of all switches of given type
420  * @type: type of interfaces to be affected
421  * @blocked: the new state
422  *
423  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
424  * Please refer to __rfkill_switch_all() for details.
425  *
426  * Does nothing if the EPO lock is active.
427  */
428 void rfkill_switch_all(enum rfkill_type type, bool blocked)
429 {
430         if (atomic_read(&rfkill_input_disabled))
431                 return;
432
433         mutex_lock(&rfkill_global_mutex);
434
435         if (!rfkill_epo_lock_active)
436                 __rfkill_switch_all(type, blocked);
437
438         mutex_unlock(&rfkill_global_mutex);
439 }
440
441 /**
442  * rfkill_epo - emergency power off all transmitters
443  *
444  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
445  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
446  *
447  * The global state before the EPO is saved and can be restored later
448  * using rfkill_restore_states().
449  */
450 void rfkill_epo(void)
451 {
452         struct rfkill *rfkill;
453         int i;
454
455         if (atomic_read(&rfkill_input_disabled))
456                 return;
457
458         mutex_lock(&rfkill_global_mutex);
459
460         rfkill_epo_lock_active = true;
461         list_for_each_entry(rfkill, &rfkill_list, node)
462                 rfkill_set_block(rfkill, true);
463
464         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
465                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
466                 rfkill_global_states[i].cur = true;
467         }
468
469         mutex_unlock(&rfkill_global_mutex);
470 }
471
472 /**
473  * rfkill_restore_states - restore global states
474  *
475  * Restore (and sync switches to) the global state from the
476  * states in rfkill_default_states.  This can undo the effects of
477  * a call to rfkill_epo().
478  */
479 void rfkill_restore_states(void)
480 {
481         int i;
482
483         if (atomic_read(&rfkill_input_disabled))
484                 return;
485
486         mutex_lock(&rfkill_global_mutex);
487
488         rfkill_epo_lock_active = false;
489         for (i = 0; i < NUM_RFKILL_TYPES; i++)
490                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
491         mutex_unlock(&rfkill_global_mutex);
492 }
493
494 /**
495  * rfkill_remove_epo_lock - unlock state changes
496  *
497  * Used by rfkill-input manually unlock state changes, when
498  * the EPO switch is deactivated.
499  */
500 void rfkill_remove_epo_lock(void)
501 {
502         if (atomic_read(&rfkill_input_disabled))
503                 return;
504
505         mutex_lock(&rfkill_global_mutex);
506         rfkill_epo_lock_active = false;
507         mutex_unlock(&rfkill_global_mutex);
508 }
509
510 /**
511  * rfkill_is_epo_lock_active - returns true EPO is active
512  *
513  * Returns 0 (false) if there is NOT an active EPO contidion,
514  * and 1 (true) if there is an active EPO contition, which
515  * locks all radios in one of the BLOCKED states.
516  *
517  * Can be called in atomic context.
518  */
519 bool rfkill_is_epo_lock_active(void)
520 {
521         return rfkill_epo_lock_active;
522 }
523
524 /**
525  * rfkill_get_global_sw_state - returns global state for a type
526  * @type: the type to get the global state of
527  *
528  * Returns the current global state for a given wireless
529  * device type.
530  */
531 bool rfkill_get_global_sw_state(const enum rfkill_type type)
532 {
533         return rfkill_global_states[type].cur;
534 }
535 #endif
536
537 bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
538 {
539         unsigned long flags;
540         bool ret, prev;
541
542         BUG_ON(!rfkill);
543
544         spin_lock_irqsave(&rfkill->lock, flags);
545         prev = !!(rfkill->state & RFKILL_BLOCK_HW);
546         if (blocked)
547                 rfkill->state |= RFKILL_BLOCK_HW;
548         else
549                 rfkill->state &= ~RFKILL_BLOCK_HW;
550         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
551         spin_unlock_irqrestore(&rfkill->lock, flags);
552
553         rfkill_led_trigger_event(rfkill);
554         rfkill_global_led_trigger_event();
555
556         if (rfkill->registered && prev != blocked)
557                 schedule_work(&rfkill->uevent_work);
558
559         return ret;
560 }
561 EXPORT_SYMBOL(rfkill_set_hw_state);
562
563 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
564 {
565         u32 bit = RFKILL_BLOCK_SW;
566
567         /* if in a ops->set_block right now, use other bit */
568         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
569                 bit = RFKILL_BLOCK_SW_PREV;
570
571         if (blocked)
572                 rfkill->state |= bit;
573         else
574                 rfkill->state &= ~bit;
575 }
576
577 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
578 {
579         unsigned long flags;
580         bool prev, hwblock;
581
582         BUG_ON(!rfkill);
583
584         spin_lock_irqsave(&rfkill->lock, flags);
585         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
586         __rfkill_set_sw_state(rfkill, blocked);
587         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
588         blocked = blocked || hwblock;
589         spin_unlock_irqrestore(&rfkill->lock, flags);
590
591         if (!rfkill->registered)
592                 return blocked;
593
594         if (prev != blocked && !hwblock)
595                 schedule_work(&rfkill->uevent_work);
596
597         rfkill_led_trigger_event(rfkill);
598         rfkill_global_led_trigger_event();
599
600         return blocked;
601 }
602 EXPORT_SYMBOL(rfkill_set_sw_state);
603
604 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
605 {
606         unsigned long flags;
607
608         BUG_ON(!rfkill);
609         BUG_ON(rfkill->registered);
610
611         spin_lock_irqsave(&rfkill->lock, flags);
612         __rfkill_set_sw_state(rfkill, blocked);
613         rfkill->persistent = true;
614         spin_unlock_irqrestore(&rfkill->lock, flags);
615 }
616 EXPORT_SYMBOL(rfkill_init_sw_state);
617
618 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
619 {
620         unsigned long flags;
621         bool swprev, hwprev;
622
623         BUG_ON(!rfkill);
624
625         spin_lock_irqsave(&rfkill->lock, flags);
626
627         /*
628          * No need to care about prev/setblock ... this is for uevent only
629          * and that will get triggered by rfkill_set_block anyway.
630          */
631         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
632         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
633         __rfkill_set_sw_state(rfkill, sw);
634         if (hw)
635                 rfkill->state |= RFKILL_BLOCK_HW;
636         else
637                 rfkill->state &= ~RFKILL_BLOCK_HW;
638
639         spin_unlock_irqrestore(&rfkill->lock, flags);
640
641         if (!rfkill->registered) {
642                 rfkill->persistent = true;
643         } else {
644                 if (swprev != sw || hwprev != hw)
645                         schedule_work(&rfkill->uevent_work);
646
647                 rfkill_led_trigger_event(rfkill);
648                 rfkill_global_led_trigger_event();
649         }
650 }
651 EXPORT_SYMBOL(rfkill_set_states);
652
653 static const char * const rfkill_types[] = {
654         NULL, /* RFKILL_TYPE_ALL */
655         "wlan",
656         "bluetooth",
657         "ultrawideband",
658         "wimax",
659         "wwan",
660         "gps",
661         "fm",
662         "nfc",
663 };
664
665 enum rfkill_type rfkill_find_type(const char *name)
666 {
667         int i;
668
669         BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
670
671         if (!name)
672                 return RFKILL_TYPE_ALL;
673
674         for (i = 1; i < NUM_RFKILL_TYPES; i++)
675                 if (!strcmp(name, rfkill_types[i]))
676                         return i;
677         return RFKILL_TYPE_ALL;
678 }
679 EXPORT_SYMBOL(rfkill_find_type);
680
681 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
682                          char *buf)
683 {
684         struct rfkill *rfkill = to_rfkill(dev);
685
686         return sprintf(buf, "%s\n", rfkill->name);
687 }
688 static DEVICE_ATTR_RO(name);
689
690 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
691                          char *buf)
692 {
693         struct rfkill *rfkill = to_rfkill(dev);
694
695         return sprintf(buf, "%s\n", rfkill_types[rfkill->type]);
696 }
697 static DEVICE_ATTR_RO(type);
698
699 static ssize_t index_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", rfkill->idx);
705 }
706 static DEVICE_ATTR_RO(index);
707
708 static ssize_t persistent_show(struct device *dev,
709                                struct device_attribute *attr, char *buf)
710 {
711         struct rfkill *rfkill = to_rfkill(dev);
712
713         return sprintf(buf, "%d\n", rfkill->persistent);
714 }
715 static DEVICE_ATTR_RO(persistent);
716
717 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
718                          char *buf)
719 {
720         struct rfkill *rfkill = to_rfkill(dev);
721
722         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
723 }
724 static DEVICE_ATTR_RO(hard);
725
726 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
727                          char *buf)
728 {
729         struct rfkill *rfkill = to_rfkill(dev);
730
731         return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
732 }
733
734 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
735                           const char *buf, size_t count)
736 {
737         struct rfkill *rfkill = to_rfkill(dev);
738         unsigned long state;
739         int err;
740
741         if (!capable(CAP_NET_ADMIN))
742                 return -EPERM;
743
744         err = kstrtoul(buf, 0, &state);
745         if (err)
746                 return err;
747
748         if (state > 1 )
749                 return -EINVAL;
750
751         mutex_lock(&rfkill_global_mutex);
752         rfkill_set_block(rfkill, state);
753         mutex_unlock(&rfkill_global_mutex);
754
755         return count;
756 }
757 static DEVICE_ATTR_RW(soft);
758
759 static u8 user_state_from_blocked(unsigned long state)
760 {
761         if (state & RFKILL_BLOCK_HW)
762                 return RFKILL_USER_STATE_HARD_BLOCKED;
763         if (state & RFKILL_BLOCK_SW)
764                 return RFKILL_USER_STATE_SOFT_BLOCKED;
765
766         return RFKILL_USER_STATE_UNBLOCKED;
767 }
768
769 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
770                           char *buf)
771 {
772         struct rfkill *rfkill = to_rfkill(dev);
773
774         return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
775 }
776
777 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
778                            const char *buf, size_t count)
779 {
780         struct rfkill *rfkill = to_rfkill(dev);
781         unsigned long state;
782         int err;
783
784         if (!capable(CAP_NET_ADMIN))
785                 return -EPERM;
786
787         err = kstrtoul(buf, 0, &state);
788         if (err)
789                 return err;
790
791         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
792             state != RFKILL_USER_STATE_UNBLOCKED)
793                 return -EINVAL;
794
795         mutex_lock(&rfkill_global_mutex);
796         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
797         mutex_unlock(&rfkill_global_mutex);
798
799         return count;
800 }
801 static DEVICE_ATTR_RW(state);
802
803 static struct attribute *rfkill_dev_attrs[] = {
804         &dev_attr_name.attr,
805         &dev_attr_type.attr,
806         &dev_attr_index.attr,
807         &dev_attr_persistent.attr,
808         &dev_attr_state.attr,
809         &dev_attr_soft.attr,
810         &dev_attr_hard.attr,
811         NULL,
812 };
813 ATTRIBUTE_GROUPS(rfkill_dev);
814
815 static void rfkill_release(struct device *dev)
816 {
817         struct rfkill *rfkill = to_rfkill(dev);
818
819         kfree(rfkill);
820 }
821
822 static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
823 {
824         struct rfkill *rfkill = to_rfkill(dev);
825         unsigned long flags;
826         u32 state;
827         int error;
828
829         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
830         if (error)
831                 return error;
832         error = add_uevent_var(env, "RFKILL_TYPE=%s",
833                                rfkill_types[rfkill->type]);
834         if (error)
835                 return error;
836         spin_lock_irqsave(&rfkill->lock, flags);
837         state = rfkill->state;
838         spin_unlock_irqrestore(&rfkill->lock, flags);
839         error = add_uevent_var(env, "RFKILL_STATE=%d",
840                                user_state_from_blocked(state));
841         return error;
842 }
843
844 void rfkill_pause_polling(struct rfkill *rfkill)
845 {
846         BUG_ON(!rfkill);
847
848         if (!rfkill->ops->poll)
849                 return;
850
851         rfkill->polling_paused = true;
852         cancel_delayed_work_sync(&rfkill->poll_work);
853 }
854 EXPORT_SYMBOL(rfkill_pause_polling);
855
856 void rfkill_resume_polling(struct rfkill *rfkill)
857 {
858         BUG_ON(!rfkill);
859
860         if (!rfkill->ops->poll)
861                 return;
862
863         rfkill->polling_paused = false;
864
865         if (rfkill->suspended)
866                 return;
867
868         queue_delayed_work(system_power_efficient_wq,
869                            &rfkill->poll_work, 0);
870 }
871 EXPORT_SYMBOL(rfkill_resume_polling);
872
873 #ifdef CONFIG_PM_SLEEP
874 static int rfkill_suspend(struct device *dev)
875 {
876         struct rfkill *rfkill = to_rfkill(dev);
877
878         rfkill->suspended = true;
879         cancel_delayed_work_sync(&rfkill->poll_work);
880
881         return 0;
882 }
883
884 static int rfkill_resume(struct device *dev)
885 {
886         struct rfkill *rfkill = to_rfkill(dev);
887         bool cur;
888
889         rfkill->suspended = false;
890
891         if (!rfkill->persistent) {
892                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
893                 rfkill_set_block(rfkill, cur);
894         }
895
896         if (rfkill->ops->poll && !rfkill->polling_paused)
897                 queue_delayed_work(system_power_efficient_wq,
898                                    &rfkill->poll_work, 0);
899
900         return 0;
901 }
902
903 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
904 #define RFKILL_PM_OPS (&rfkill_pm_ops)
905 #else
906 #define RFKILL_PM_OPS NULL
907 #endif
908
909 static struct class rfkill_class = {
910         .name           = "rfkill",
911         .dev_release    = rfkill_release,
912         .dev_groups     = rfkill_dev_groups,
913         .dev_uevent     = rfkill_dev_uevent,
914         .pm             = RFKILL_PM_OPS,
915 };
916
917 bool rfkill_blocked(struct rfkill *rfkill)
918 {
919         unsigned long flags;
920         u32 state;
921
922         spin_lock_irqsave(&rfkill->lock, flags);
923         state = rfkill->state;
924         spin_unlock_irqrestore(&rfkill->lock, flags);
925
926         return !!(state & RFKILL_BLOCK_ANY);
927 }
928 EXPORT_SYMBOL(rfkill_blocked);
929
930
931 struct rfkill * __must_check rfkill_alloc(const char *name,
932                                           struct device *parent,
933                                           const enum rfkill_type type,
934                                           const struct rfkill_ops *ops,
935                                           void *ops_data)
936 {
937         struct rfkill *rfkill;
938         struct device *dev;
939
940         if (WARN_ON(!ops))
941                 return NULL;
942
943         if (WARN_ON(!ops->set_block))
944                 return NULL;
945
946         if (WARN_ON(!name))
947                 return NULL;
948
949         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
950                 return NULL;
951
952         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
953         if (!rfkill)
954                 return NULL;
955
956         spin_lock_init(&rfkill->lock);
957         INIT_LIST_HEAD(&rfkill->node);
958         rfkill->type = type;
959         strcpy(rfkill->name, name);
960         rfkill->ops = ops;
961         rfkill->data = ops_data;
962
963         dev = &rfkill->dev;
964         dev->class = &rfkill_class;
965         dev->parent = parent;
966         device_initialize(dev);
967
968         return rfkill;
969 }
970 EXPORT_SYMBOL(rfkill_alloc);
971
972 static void rfkill_poll(struct work_struct *work)
973 {
974         struct rfkill *rfkill;
975
976         rfkill = container_of(work, struct rfkill, poll_work.work);
977
978         /*
979          * Poll hardware state -- driver will use one of the
980          * rfkill_set{,_hw,_sw}_state functions and use its
981          * return value to update the current status.
982          */
983         rfkill->ops->poll(rfkill, rfkill->data);
984
985         queue_delayed_work(system_power_efficient_wq,
986                 &rfkill->poll_work,
987                 round_jiffies_relative(POLL_INTERVAL));
988 }
989
990 static void rfkill_uevent_work(struct work_struct *work)
991 {
992         struct rfkill *rfkill;
993
994         rfkill = container_of(work, struct rfkill, uevent_work);
995
996         mutex_lock(&rfkill_global_mutex);
997         rfkill_event(rfkill);
998         mutex_unlock(&rfkill_global_mutex);
999 }
1000
1001 static void rfkill_sync_work(struct work_struct *work)
1002 {
1003         struct rfkill *rfkill;
1004         bool cur;
1005
1006         rfkill = container_of(work, struct rfkill, sync_work);
1007
1008         mutex_lock(&rfkill_global_mutex);
1009         cur = rfkill_global_states[rfkill->type].cur;
1010         rfkill_set_block(rfkill, cur);
1011         mutex_unlock(&rfkill_global_mutex);
1012 }
1013
1014 int __must_check rfkill_register(struct rfkill *rfkill)
1015 {
1016         static unsigned long rfkill_no;
1017         struct device *dev;
1018         int error;
1019
1020         if (!rfkill)
1021                 return -EINVAL;
1022
1023         dev = &rfkill->dev;
1024
1025         mutex_lock(&rfkill_global_mutex);
1026
1027         if (rfkill->registered) {
1028                 error = -EALREADY;
1029                 goto unlock;
1030         }
1031
1032         rfkill->idx = rfkill_no;
1033         dev_set_name(dev, "rfkill%lu", rfkill_no);
1034         rfkill_no++;
1035
1036         list_add_tail(&rfkill->node, &rfkill_list);
1037
1038         error = device_add(dev);
1039         if (error)
1040                 goto remove;
1041
1042         error = rfkill_led_trigger_register(rfkill);
1043         if (error)
1044                 goto devdel;
1045
1046         rfkill->registered = true;
1047
1048         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
1049         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
1050         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
1051
1052         if (rfkill->ops->poll)
1053                 queue_delayed_work(system_power_efficient_wq,
1054                         &rfkill->poll_work,
1055                         round_jiffies_relative(POLL_INTERVAL));
1056
1057         if (!rfkill->persistent || rfkill_epo_lock_active) {
1058                 schedule_work(&rfkill->sync_work);
1059         } else {
1060 #ifdef CONFIG_RFKILL_INPUT
1061                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
1062
1063                 if (!atomic_read(&rfkill_input_disabled))
1064                         __rfkill_switch_all(rfkill->type, soft_blocked);
1065 #endif
1066         }
1067
1068         rfkill_global_led_trigger_event();
1069         rfkill_send_events(rfkill, RFKILL_OP_ADD);
1070
1071         mutex_unlock(&rfkill_global_mutex);
1072         return 0;
1073
1074  devdel:
1075         device_del(&rfkill->dev);
1076  remove:
1077         list_del_init(&rfkill->node);
1078  unlock:
1079         mutex_unlock(&rfkill_global_mutex);
1080         return error;
1081 }
1082 EXPORT_SYMBOL(rfkill_register);
1083
1084 void rfkill_unregister(struct rfkill *rfkill)
1085 {
1086         BUG_ON(!rfkill);
1087
1088         if (rfkill->ops->poll)
1089                 cancel_delayed_work_sync(&rfkill->poll_work);
1090
1091         cancel_work_sync(&rfkill->uevent_work);
1092         cancel_work_sync(&rfkill->sync_work);
1093
1094         rfkill->registered = false;
1095
1096         device_del(&rfkill->dev);
1097
1098         mutex_lock(&rfkill_global_mutex);
1099         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1100         list_del_init(&rfkill->node);
1101         rfkill_global_led_trigger_event();
1102         mutex_unlock(&rfkill_global_mutex);
1103
1104         rfkill_led_trigger_unregister(rfkill);
1105 }
1106 EXPORT_SYMBOL(rfkill_unregister);
1107
1108 void rfkill_destroy(struct rfkill *rfkill)
1109 {
1110         if (rfkill)
1111                 put_device(&rfkill->dev);
1112 }
1113 EXPORT_SYMBOL(rfkill_destroy);
1114
1115 static int rfkill_fop_open(struct inode *inode, struct file *file)
1116 {
1117         struct rfkill_data *data;
1118         struct rfkill *rfkill;
1119         struct rfkill_int_event *ev, *tmp;
1120
1121         data = kzalloc(sizeof(*data), GFP_KERNEL);
1122         if (!data)
1123                 return -ENOMEM;
1124
1125         INIT_LIST_HEAD(&data->events);
1126         mutex_init(&data->mtx);
1127         init_waitqueue_head(&data->read_wait);
1128
1129         mutex_lock(&rfkill_global_mutex);
1130         mutex_lock(&data->mtx);
1131         /*
1132          * start getting events from elsewhere but hold mtx to get
1133          * startup events added first
1134          */
1135
1136         list_for_each_entry(rfkill, &rfkill_list, node) {
1137                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1138                 if (!ev)
1139                         goto free;
1140                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1141                 list_add_tail(&ev->list, &data->events);
1142         }
1143         list_add(&data->list, &rfkill_fds);
1144         mutex_unlock(&data->mtx);
1145         mutex_unlock(&rfkill_global_mutex);
1146
1147         file->private_data = data;
1148
1149         return nonseekable_open(inode, file);
1150
1151  free:
1152         mutex_unlock(&data->mtx);
1153         mutex_unlock(&rfkill_global_mutex);
1154         mutex_destroy(&data->mtx);
1155         list_for_each_entry_safe(ev, tmp, &data->events, list)
1156                 kfree(ev);
1157         kfree(data);
1158         return -ENOMEM;
1159 }
1160
1161 static __poll_t rfkill_fop_poll(struct file *file, poll_table *wait)
1162 {
1163         struct rfkill_data *data = file->private_data;
1164         __poll_t res = EPOLLOUT | EPOLLWRNORM;
1165
1166         poll_wait(file, &data->read_wait, wait);
1167
1168         mutex_lock(&data->mtx);
1169         if (!list_empty(&data->events))
1170                 res = EPOLLIN | EPOLLRDNORM;
1171         mutex_unlock(&data->mtx);
1172
1173         return res;
1174 }
1175
1176 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1177                                size_t count, loff_t *pos)
1178 {
1179         struct rfkill_data *data = file->private_data;
1180         struct rfkill_int_event *ev;
1181         unsigned long sz;
1182         int ret;
1183
1184         mutex_lock(&data->mtx);
1185
1186         while (list_empty(&data->events)) {
1187                 if (file->f_flags & O_NONBLOCK) {
1188                         ret = -EAGAIN;
1189                         goto out;
1190                 }
1191                 mutex_unlock(&data->mtx);
1192                 /* since we re-check and it just compares pointers,
1193                  * using !list_empty() without locking isn't a problem
1194                  */
1195                 ret = wait_event_interruptible(data->read_wait,
1196                                                !list_empty(&data->events));
1197                 mutex_lock(&data->mtx);
1198
1199                 if (ret)
1200                         goto out;
1201         }
1202
1203         ev = list_first_entry(&data->events, struct rfkill_int_event,
1204                                 list);
1205
1206         sz = min_t(unsigned long, sizeof(ev->ev), count);
1207         ret = sz;
1208         if (copy_to_user(buf, &ev->ev, sz))
1209                 ret = -EFAULT;
1210
1211         list_del(&ev->list);
1212         kfree(ev);
1213  out:
1214         mutex_unlock(&data->mtx);
1215         return ret;
1216 }
1217
1218 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1219                                 size_t count, loff_t *pos)
1220 {
1221         struct rfkill *rfkill;
1222         struct rfkill_event ev;
1223         int ret;
1224
1225         /* we don't need the 'hard' variable but accept it */
1226         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1227                 return -EINVAL;
1228
1229         /*
1230          * Copy as much data as we can accept into our 'ev' buffer,
1231          * but tell userspace how much we've copied so it can determine
1232          * our API version even in a write() call, if it cares.
1233          */
1234         count = min(count, sizeof(ev));
1235         if (copy_from_user(&ev, buf, count))
1236                 return -EFAULT;
1237
1238         if (ev.type >= NUM_RFKILL_TYPES)
1239                 return -EINVAL;
1240
1241         mutex_lock(&rfkill_global_mutex);
1242
1243         switch (ev.op) {
1244         case RFKILL_OP_CHANGE_ALL:
1245                 rfkill_update_global_state(ev.type, ev.soft);
1246                 list_for_each_entry(rfkill, &rfkill_list, node)
1247                         if (rfkill->type == ev.type ||
1248                             ev.type == RFKILL_TYPE_ALL)
1249                                 rfkill_set_block(rfkill, ev.soft);
1250                 ret = 0;
1251                 break;
1252         case RFKILL_OP_CHANGE:
1253                 list_for_each_entry(rfkill, &rfkill_list, node)
1254                         if (rfkill->idx == ev.idx &&
1255                             (rfkill->type == ev.type ||
1256                              ev.type == RFKILL_TYPE_ALL))
1257                                 rfkill_set_block(rfkill, ev.soft);
1258                 ret = 0;
1259                 break;
1260         default:
1261                 ret = -EINVAL;
1262                 break;
1263         }
1264
1265         mutex_unlock(&rfkill_global_mutex);
1266
1267         return ret ?: count;
1268 }
1269
1270 static int rfkill_fop_release(struct inode *inode, struct file *file)
1271 {
1272         struct rfkill_data *data = file->private_data;
1273         struct rfkill_int_event *ev, *tmp;
1274
1275         mutex_lock(&rfkill_global_mutex);
1276         list_del(&data->list);
1277         mutex_unlock(&rfkill_global_mutex);
1278
1279         mutex_destroy(&data->mtx);
1280         list_for_each_entry_safe(ev, tmp, &data->events, list)
1281                 kfree(ev);
1282
1283 #ifdef CONFIG_RFKILL_INPUT
1284         if (data->input_handler)
1285                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1286                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1287 #endif
1288
1289         kfree(data);
1290
1291         return 0;
1292 }
1293
1294 #ifdef CONFIG_RFKILL_INPUT
1295 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1296                              unsigned long arg)
1297 {
1298         struct rfkill_data *data = file->private_data;
1299
1300         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1301                 return -ENOSYS;
1302
1303         if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
1304                 return -ENOSYS;
1305
1306         mutex_lock(&data->mtx);
1307
1308         if (!data->input_handler) {
1309                 if (atomic_inc_return(&rfkill_input_disabled) == 1)
1310                         printk(KERN_DEBUG "rfkill: input handler disabled\n");
1311                 data->input_handler = true;
1312         }
1313
1314         mutex_unlock(&data->mtx);
1315
1316         return 0;
1317 }
1318 #endif
1319
1320 static const struct file_operations rfkill_fops = {
1321         .owner          = THIS_MODULE,
1322         .open           = rfkill_fop_open,
1323         .read           = rfkill_fop_read,
1324         .write          = rfkill_fop_write,
1325         .poll           = rfkill_fop_poll,
1326         .release        = rfkill_fop_release,
1327 #ifdef CONFIG_RFKILL_INPUT
1328         .unlocked_ioctl = rfkill_fop_ioctl,
1329         .compat_ioctl   = rfkill_fop_ioctl,
1330 #endif
1331         .llseek         = no_llseek,
1332 };
1333
1334 #define RFKILL_NAME "rfkill"
1335
1336 static struct miscdevice rfkill_miscdev = {
1337         .fops   = &rfkill_fops,
1338         .name   = RFKILL_NAME,
1339         .minor  = RFKILL_MINOR,
1340 };
1341
1342 static int __init rfkill_init(void)
1343 {
1344         int error;
1345
1346         rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1347
1348         error = class_register(&rfkill_class);
1349         if (error)
1350                 goto error_class;
1351
1352         error = misc_register(&rfkill_miscdev);
1353         if (error)
1354                 goto error_misc;
1355
1356         error = rfkill_global_led_trigger_register();
1357         if (error)
1358                 goto error_led_trigger;
1359
1360 #ifdef CONFIG_RFKILL_INPUT
1361         error = rfkill_handler_init();
1362         if (error)
1363                 goto error_input;
1364 #endif
1365
1366         return 0;
1367
1368 #ifdef CONFIG_RFKILL_INPUT
1369 error_input:
1370         rfkill_global_led_trigger_unregister();
1371 #endif
1372 error_led_trigger:
1373         misc_deregister(&rfkill_miscdev);
1374 error_misc:
1375         class_unregister(&rfkill_class);
1376 error_class:
1377         return error;
1378 }
1379 subsys_initcall(rfkill_init);
1380
1381 static void __exit rfkill_exit(void)
1382 {
1383 #ifdef CONFIG_RFKILL_INPUT
1384         rfkill_handler_exit();
1385 #endif
1386         rfkill_global_led_trigger_unregister();
1387         misc_deregister(&rfkill_miscdev);
1388         class_unregister(&rfkill_class);
1389 }
1390 module_exit(rfkill_exit);
1391
1392 MODULE_ALIAS_MISCDEV(RFKILL_MINOR);
1393 MODULE_ALIAS("devname:" RFKILL_NAME);