net: Use sendmsg(MSG_SPLICE_PAGES) not sendpage in skb_send_sock()
[platform/kernel/linux-rpi.git] / net / rfkill / core.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2006 - 2007 Ivo van Doorn
4  * Copyright (C) 2007 Dmitry Torokhov
5  * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
6  */
7
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/workqueue.h>
12 #include <linux/capability.h>
13 #include <linux/list.h>
14 #include <linux/mutex.h>
15 #include <linux/rfkill.h>
16 #include <linux/sched.h>
17 #include <linux/spinlock.h>
18 #include <linux/device.h>
19 #include <linux/miscdevice.h>
20 #include <linux/wait.h>
21 #include <linux/poll.h>
22 #include <linux/fs.h>
23 #include <linux/slab.h>
24
25 #include "rfkill.h"
26
27 #define POLL_INTERVAL           (5 * HZ)
28
29 #define RFKILL_BLOCK_HW         BIT(0)
30 #define RFKILL_BLOCK_SW         BIT(1)
31 #define RFKILL_BLOCK_SW_PREV    BIT(2)
32 #define RFKILL_BLOCK_ANY        (RFKILL_BLOCK_HW |\
33                                  RFKILL_BLOCK_SW |\
34                                  RFKILL_BLOCK_SW_PREV)
35 #define RFKILL_BLOCK_SW_SETCALL BIT(31)
36
37 struct rfkill {
38         spinlock_t              lock;
39
40         enum rfkill_type        type;
41
42         unsigned long           state;
43         unsigned long           hard_block_reasons;
44
45         u32                     idx;
46
47         bool                    registered;
48         bool                    persistent;
49         bool                    polling_paused;
50         bool                    suspended;
51
52         const struct rfkill_ops *ops;
53         void                    *data;
54
55 #ifdef CONFIG_RFKILL_LEDS
56         struct led_trigger      led_trigger;
57         const char              *ledtrigname;
58 #endif
59
60         struct device           dev;
61         struct list_head        node;
62
63         struct delayed_work     poll_work;
64         struct work_struct      uevent_work;
65         struct work_struct      sync_work;
66         char                    name[];
67 };
68 #define to_rfkill(d)    container_of(d, struct rfkill, dev)
69
70 struct rfkill_int_event {
71         struct list_head        list;
72         struct rfkill_event_ext ev;
73 };
74
75 struct rfkill_data {
76         struct list_head        list;
77         struct list_head        events;
78         struct mutex            mtx;
79         wait_queue_head_t       read_wait;
80         bool                    input_handler;
81         u8                      max_size;
82 };
83
84
85 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
86 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
87 MODULE_DESCRIPTION("RF switch support");
88 MODULE_LICENSE("GPL");
89
90
91 /*
92  * The locking here should be made much smarter, we currently have
93  * a bit of a stupid situation because drivers might want to register
94  * the rfkill struct under their own lock, and take this lock during
95  * rfkill method calls -- which will cause an AB-BA deadlock situation.
96  *
97  * To fix that, we need to rework this code here to be mostly lock-free
98  * and only use the mutex for list manipulations, not to protect the
99  * various other global variables. Then we can avoid holding the mutex
100  * around driver operations, and all is happy.
101  */
102 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
103 static DEFINE_MUTEX(rfkill_global_mutex);
104 static LIST_HEAD(rfkill_fds);   /* list of open fds of /dev/rfkill */
105
106 static unsigned int rfkill_default_state = 1;
107 module_param_named(default_state, rfkill_default_state, uint, 0444);
108 MODULE_PARM_DESC(default_state,
109                  "Default initial state for all radio types, 0 = radio off");
110
111 static struct {
112         bool cur, sav;
113 } rfkill_global_states[NUM_RFKILL_TYPES];
114
115 static bool rfkill_epo_lock_active;
116
117
118 #ifdef CONFIG_RFKILL_LEDS
119 static void rfkill_led_trigger_event(struct rfkill *rfkill)
120 {
121         struct led_trigger *trigger;
122
123         if (!rfkill->registered)
124                 return;
125
126         trigger = &rfkill->led_trigger;
127
128         if (rfkill->state & RFKILL_BLOCK_ANY)
129                 led_trigger_event(trigger, LED_OFF);
130         else
131                 led_trigger_event(trigger, LED_FULL);
132 }
133
134 static int rfkill_led_trigger_activate(struct led_classdev *led)
135 {
136         struct rfkill *rfkill;
137
138         rfkill = container_of(led->trigger, struct rfkill, led_trigger);
139
140         rfkill_led_trigger_event(rfkill);
141
142         return 0;
143 }
144
145 const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
146 {
147         return rfkill->led_trigger.name;
148 }
149 EXPORT_SYMBOL(rfkill_get_led_trigger_name);
150
151 void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
152 {
153         BUG_ON(!rfkill);
154
155         rfkill->ledtrigname = name;
156 }
157 EXPORT_SYMBOL(rfkill_set_led_trigger_name);
158
159 static int rfkill_led_trigger_register(struct rfkill *rfkill)
160 {
161         rfkill->led_trigger.name = rfkill->ledtrigname
162                                         ? : dev_name(&rfkill->dev);
163         rfkill->led_trigger.activate = rfkill_led_trigger_activate;
164         return led_trigger_register(&rfkill->led_trigger);
165 }
166
167 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
168 {
169         led_trigger_unregister(&rfkill->led_trigger);
170 }
171
172 static struct led_trigger rfkill_any_led_trigger;
173 static struct led_trigger rfkill_none_led_trigger;
174 static struct work_struct rfkill_global_led_trigger_work;
175
176 static void rfkill_global_led_trigger_worker(struct work_struct *work)
177 {
178         enum led_brightness brightness = LED_OFF;
179         struct rfkill *rfkill;
180
181         mutex_lock(&rfkill_global_mutex);
182         list_for_each_entry(rfkill, &rfkill_list, node) {
183                 if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
184                         brightness = LED_FULL;
185                         break;
186                 }
187         }
188         mutex_unlock(&rfkill_global_mutex);
189
190         led_trigger_event(&rfkill_any_led_trigger, brightness);
191         led_trigger_event(&rfkill_none_led_trigger,
192                           brightness == LED_OFF ? LED_FULL : LED_OFF);
193 }
194
195 static void rfkill_global_led_trigger_event(void)
196 {
197         schedule_work(&rfkill_global_led_trigger_work);
198 }
199
200 static int rfkill_global_led_trigger_register(void)
201 {
202         int ret;
203
204         INIT_WORK(&rfkill_global_led_trigger_work,
205                         rfkill_global_led_trigger_worker);
206
207         rfkill_any_led_trigger.name = "rfkill-any";
208         ret = led_trigger_register(&rfkill_any_led_trigger);
209         if (ret)
210                 return ret;
211
212         rfkill_none_led_trigger.name = "rfkill-none";
213         ret = led_trigger_register(&rfkill_none_led_trigger);
214         if (ret)
215                 led_trigger_unregister(&rfkill_any_led_trigger);
216         else
217                 /* Delay activation until all global triggers are registered */
218                 rfkill_global_led_trigger_event();
219
220         return ret;
221 }
222
223 static void rfkill_global_led_trigger_unregister(void)
224 {
225         led_trigger_unregister(&rfkill_none_led_trigger);
226         led_trigger_unregister(&rfkill_any_led_trigger);
227         cancel_work_sync(&rfkill_global_led_trigger_work);
228 }
229 #else
230 static void rfkill_led_trigger_event(struct rfkill *rfkill)
231 {
232 }
233
234 static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
235 {
236         return 0;
237 }
238
239 static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
240 {
241 }
242
243 static void rfkill_global_led_trigger_event(void)
244 {
245 }
246
247 static int rfkill_global_led_trigger_register(void)
248 {
249         return 0;
250 }
251
252 static void rfkill_global_led_trigger_unregister(void)
253 {
254 }
255 #endif /* CONFIG_RFKILL_LEDS */
256
257 static void rfkill_fill_event(struct rfkill_event_ext *ev,
258                               struct rfkill *rfkill,
259                               enum rfkill_operation op)
260 {
261         unsigned long flags;
262
263         ev->idx = rfkill->idx;
264         ev->type = rfkill->type;
265         ev->op = op;
266
267         spin_lock_irqsave(&rfkill->lock, flags);
268         ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
269         ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
270                                         RFKILL_BLOCK_SW_PREV));
271         ev->hard_block_reasons = rfkill->hard_block_reasons;
272         spin_unlock_irqrestore(&rfkill->lock, flags);
273 }
274
275 static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
276 {
277         struct rfkill_data *data;
278         struct rfkill_int_event *ev;
279
280         list_for_each_entry(data, &rfkill_fds, list) {
281                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
282                 if (!ev)
283                         continue;
284                 rfkill_fill_event(&ev->ev, rfkill, op);
285                 mutex_lock(&data->mtx);
286                 list_add_tail(&ev->list, &data->events);
287                 mutex_unlock(&data->mtx);
288                 wake_up_interruptible(&data->read_wait);
289         }
290 }
291
292 static void rfkill_event(struct rfkill *rfkill)
293 {
294         if (!rfkill->registered)
295                 return;
296
297         kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
298
299         /* also send event to /dev/rfkill */
300         rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
301 }
302
303 /**
304  * rfkill_set_block - wrapper for set_block method
305  *
306  * @rfkill: the rfkill struct to use
307  * @blocked: the new software state
308  *
309  * Calls the set_block method (when applicable) and handles notifications
310  * etc. as well.
311  */
312 static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
313 {
314         unsigned long flags;
315         bool prev, curr;
316         int err;
317
318         if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
319                 return;
320
321         /*
322          * Some platforms (...!) generate input events which affect the
323          * _hard_ kill state -- whenever something tries to change the
324          * current software state query the hardware state too.
325          */
326         if (rfkill->ops->query)
327                 rfkill->ops->query(rfkill, rfkill->data);
328
329         spin_lock_irqsave(&rfkill->lock, flags);
330         prev = rfkill->state & RFKILL_BLOCK_SW;
331
332         if (prev)
333                 rfkill->state |= RFKILL_BLOCK_SW_PREV;
334         else
335                 rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
336
337         if (blocked)
338                 rfkill->state |= RFKILL_BLOCK_SW;
339         else
340                 rfkill->state &= ~RFKILL_BLOCK_SW;
341
342         rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
343         spin_unlock_irqrestore(&rfkill->lock, flags);
344
345         err = rfkill->ops->set_block(rfkill->data, blocked);
346
347         spin_lock_irqsave(&rfkill->lock, flags);
348         if (err) {
349                 /*
350                  * Failed -- reset status to _PREV, which may be different
351                  * from what we have set _PREV to earlier in this function
352                  * if rfkill_set_sw_state was invoked.
353                  */
354                 if (rfkill->state & RFKILL_BLOCK_SW_PREV)
355                         rfkill->state |= RFKILL_BLOCK_SW;
356                 else
357                         rfkill->state &= ~RFKILL_BLOCK_SW;
358         }
359         rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
360         rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
361         curr = rfkill->state & RFKILL_BLOCK_SW;
362         spin_unlock_irqrestore(&rfkill->lock, flags);
363
364         rfkill_led_trigger_event(rfkill);
365         rfkill_global_led_trigger_event();
366
367         if (prev != curr)
368                 rfkill_event(rfkill);
369 }
370
371 static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
372 {
373         int i;
374
375         if (type != RFKILL_TYPE_ALL) {
376                 rfkill_global_states[type].cur = blocked;
377                 return;
378         }
379
380         for (i = 0; i < NUM_RFKILL_TYPES; i++)
381                 rfkill_global_states[i].cur = blocked;
382 }
383
384 #ifdef CONFIG_RFKILL_INPUT
385 static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
386
387 /**
388  * __rfkill_switch_all - Toggle state of all switches of given type
389  * @type: type of interfaces to be affected
390  * @blocked: the new state
391  *
392  * This function sets the state of all switches of given type,
393  * unless a specific switch is suspended.
394  *
395  * Caller must have acquired rfkill_global_mutex.
396  */
397 static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
398 {
399         struct rfkill *rfkill;
400
401         rfkill_update_global_state(type, blocked);
402         list_for_each_entry(rfkill, &rfkill_list, node) {
403                 if (rfkill->type != type && type != RFKILL_TYPE_ALL)
404                         continue;
405
406                 rfkill_set_block(rfkill, blocked);
407         }
408 }
409
410 /**
411  * rfkill_switch_all - Toggle state of all switches of given type
412  * @type: type of interfaces to be affected
413  * @blocked: the new state
414  *
415  * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
416  * Please refer to __rfkill_switch_all() for details.
417  *
418  * Does nothing if the EPO lock is active.
419  */
420 void rfkill_switch_all(enum rfkill_type type, bool blocked)
421 {
422         if (atomic_read(&rfkill_input_disabled))
423                 return;
424
425         mutex_lock(&rfkill_global_mutex);
426
427         if (!rfkill_epo_lock_active)
428                 __rfkill_switch_all(type, blocked);
429
430         mutex_unlock(&rfkill_global_mutex);
431 }
432
433 /**
434  * rfkill_epo - emergency power off all transmitters
435  *
436  * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
437  * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
438  *
439  * The global state before the EPO is saved and can be restored later
440  * using rfkill_restore_states().
441  */
442 void rfkill_epo(void)
443 {
444         struct rfkill *rfkill;
445         int i;
446
447         if (atomic_read(&rfkill_input_disabled))
448                 return;
449
450         mutex_lock(&rfkill_global_mutex);
451
452         rfkill_epo_lock_active = true;
453         list_for_each_entry(rfkill, &rfkill_list, node)
454                 rfkill_set_block(rfkill, true);
455
456         for (i = 0; i < NUM_RFKILL_TYPES; i++) {
457                 rfkill_global_states[i].sav = rfkill_global_states[i].cur;
458                 rfkill_global_states[i].cur = true;
459         }
460
461         mutex_unlock(&rfkill_global_mutex);
462 }
463
464 /**
465  * rfkill_restore_states - restore global states
466  *
467  * Restore (and sync switches to) the global state from the
468  * states in rfkill_default_states.  This can undo the effects of
469  * a call to rfkill_epo().
470  */
471 void rfkill_restore_states(void)
472 {
473         int i;
474
475         if (atomic_read(&rfkill_input_disabled))
476                 return;
477
478         mutex_lock(&rfkill_global_mutex);
479
480         rfkill_epo_lock_active = false;
481         for (i = 0; i < NUM_RFKILL_TYPES; i++)
482                 __rfkill_switch_all(i, rfkill_global_states[i].sav);
483         mutex_unlock(&rfkill_global_mutex);
484 }
485
486 /**
487  * rfkill_remove_epo_lock - unlock state changes
488  *
489  * Used by rfkill-input manually unlock state changes, when
490  * the EPO switch is deactivated.
491  */
492 void rfkill_remove_epo_lock(void)
493 {
494         if (atomic_read(&rfkill_input_disabled))
495                 return;
496
497         mutex_lock(&rfkill_global_mutex);
498         rfkill_epo_lock_active = false;
499         mutex_unlock(&rfkill_global_mutex);
500 }
501
502 /**
503  * rfkill_is_epo_lock_active - returns true EPO is active
504  *
505  * Returns 0 (false) if there is NOT an active EPO condition,
506  * and 1 (true) if there is an active EPO condition, which
507  * locks all radios in one of the BLOCKED states.
508  *
509  * Can be called in atomic context.
510  */
511 bool rfkill_is_epo_lock_active(void)
512 {
513         return rfkill_epo_lock_active;
514 }
515
516 /**
517  * rfkill_get_global_sw_state - returns global state for a type
518  * @type: the type to get the global state of
519  *
520  * Returns the current global state for a given wireless
521  * device type.
522  */
523 bool rfkill_get_global_sw_state(const enum rfkill_type type)
524 {
525         return rfkill_global_states[type].cur;
526 }
527 #endif
528
529 bool rfkill_set_hw_state_reason(struct rfkill *rfkill,
530                                 bool blocked, unsigned long reason)
531 {
532         unsigned long flags;
533         bool ret, prev;
534
535         BUG_ON(!rfkill);
536
537         if (WARN(reason &
538             ~(RFKILL_HARD_BLOCK_SIGNAL | RFKILL_HARD_BLOCK_NOT_OWNER),
539             "hw_state reason not supported: 0x%lx", reason))
540                 return blocked;
541
542         spin_lock_irqsave(&rfkill->lock, flags);
543         prev = !!(rfkill->hard_block_reasons & reason);
544         if (blocked) {
545                 rfkill->state |= RFKILL_BLOCK_HW;
546                 rfkill->hard_block_reasons |= reason;
547         } else {
548                 rfkill->hard_block_reasons &= ~reason;
549                 if (!rfkill->hard_block_reasons)
550                         rfkill->state &= ~RFKILL_BLOCK_HW;
551         }
552         ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
553         spin_unlock_irqrestore(&rfkill->lock, flags);
554
555         rfkill_led_trigger_event(rfkill);
556         rfkill_global_led_trigger_event();
557
558         if (rfkill->registered && prev != blocked)
559                 schedule_work(&rfkill->uevent_work);
560
561         return ret;
562 }
563 EXPORT_SYMBOL(rfkill_set_hw_state_reason);
564
565 static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
566 {
567         u32 bit = RFKILL_BLOCK_SW;
568
569         /* if in a ops->set_block right now, use other bit */
570         if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
571                 bit = RFKILL_BLOCK_SW_PREV;
572
573         if (blocked)
574                 rfkill->state |= bit;
575         else
576                 rfkill->state &= ~bit;
577 }
578
579 bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
580 {
581         unsigned long flags;
582         bool prev, hwblock;
583
584         BUG_ON(!rfkill);
585
586         spin_lock_irqsave(&rfkill->lock, flags);
587         prev = !!(rfkill->state & RFKILL_BLOCK_SW);
588         __rfkill_set_sw_state(rfkill, blocked);
589         hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
590         blocked = blocked || hwblock;
591         spin_unlock_irqrestore(&rfkill->lock, flags);
592
593         if (!rfkill->registered)
594                 return blocked;
595
596         if (prev != blocked && !hwblock)
597                 schedule_work(&rfkill->uevent_work);
598
599         rfkill_led_trigger_event(rfkill);
600         rfkill_global_led_trigger_event();
601
602         return blocked;
603 }
604 EXPORT_SYMBOL(rfkill_set_sw_state);
605
606 void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
607 {
608         unsigned long flags;
609
610         BUG_ON(!rfkill);
611         BUG_ON(rfkill->registered);
612
613         spin_lock_irqsave(&rfkill->lock, flags);
614         __rfkill_set_sw_state(rfkill, blocked);
615         rfkill->persistent = true;
616         spin_unlock_irqrestore(&rfkill->lock, flags);
617 }
618 EXPORT_SYMBOL(rfkill_init_sw_state);
619
620 void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
621 {
622         unsigned long flags;
623         bool swprev, hwprev;
624
625         BUG_ON(!rfkill);
626
627         spin_lock_irqsave(&rfkill->lock, flags);
628
629         /*
630          * No need to care about prev/setblock ... this is for uevent only
631          * and that will get triggered by rfkill_set_block anyway.
632          */
633         swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
634         hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
635         __rfkill_set_sw_state(rfkill, sw);
636         if (hw)
637                 rfkill->state |= RFKILL_BLOCK_HW;
638         else
639                 rfkill->state &= ~RFKILL_BLOCK_HW;
640
641         spin_unlock_irqrestore(&rfkill->lock, flags);
642
643         if (!rfkill->registered) {
644                 rfkill->persistent = true;
645         } else {
646                 if (swprev != sw || hwprev != hw)
647                         schedule_work(&rfkill->uevent_work);
648
649                 rfkill_led_trigger_event(rfkill);
650                 rfkill_global_led_trigger_event();
651         }
652 }
653 EXPORT_SYMBOL(rfkill_set_states);
654
655 static const char * const rfkill_types[] = {
656         NULL, /* RFKILL_TYPE_ALL */
657         "wlan",
658         "bluetooth",
659         "ultrawideband",
660         "wimax",
661         "wwan",
662         "gps",
663         "fm",
664         "nfc",
665 };
666
667 enum rfkill_type rfkill_find_type(const char *name)
668 {
669         int i;
670
671         BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
672
673         if (!name)
674                 return RFKILL_TYPE_ALL;
675
676         for (i = 1; i < NUM_RFKILL_TYPES; i++)
677                 if (!strcmp(name, rfkill_types[i]))
678                         return i;
679         return RFKILL_TYPE_ALL;
680 }
681 EXPORT_SYMBOL(rfkill_find_type);
682
683 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
684                          char *buf)
685 {
686         struct rfkill *rfkill = to_rfkill(dev);
687
688         return sysfs_emit(buf, "%s\n", rfkill->name);
689 }
690 static DEVICE_ATTR_RO(name);
691
692 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
693                          char *buf)
694 {
695         struct rfkill *rfkill = to_rfkill(dev);
696
697         return sysfs_emit(buf, "%s\n", rfkill_types[rfkill->type]);
698 }
699 static DEVICE_ATTR_RO(type);
700
701 static ssize_t index_show(struct device *dev, struct device_attribute *attr,
702                           char *buf)
703 {
704         struct rfkill *rfkill = to_rfkill(dev);
705
706         return sysfs_emit(buf, "%d\n", rfkill->idx);
707 }
708 static DEVICE_ATTR_RO(index);
709
710 static ssize_t persistent_show(struct device *dev,
711                                struct device_attribute *attr, char *buf)
712 {
713         struct rfkill *rfkill = to_rfkill(dev);
714
715         return sysfs_emit(buf, "%d\n", rfkill->persistent);
716 }
717 static DEVICE_ATTR_RO(persistent);
718
719 static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
720                          char *buf)
721 {
722         struct rfkill *rfkill = to_rfkill(dev);
723
724         return sysfs_emit(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0);
725 }
726 static DEVICE_ATTR_RO(hard);
727
728 static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
729                          char *buf)
730 {
731         struct rfkill *rfkill = to_rfkill(dev);
732
733         return sysfs_emit(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0);
734 }
735
736 static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
737                           const char *buf, size_t count)
738 {
739         struct rfkill *rfkill = to_rfkill(dev);
740         unsigned long state;
741         int err;
742
743         if (!capable(CAP_NET_ADMIN))
744                 return -EPERM;
745
746         err = kstrtoul(buf, 0, &state);
747         if (err)
748                 return err;
749
750         if (state > 1 )
751                 return -EINVAL;
752
753         mutex_lock(&rfkill_global_mutex);
754         rfkill_set_block(rfkill, state);
755         mutex_unlock(&rfkill_global_mutex);
756
757         return count;
758 }
759 static DEVICE_ATTR_RW(soft);
760
761 static ssize_t hard_block_reasons_show(struct device *dev,
762                                        struct device_attribute *attr,
763                                        char *buf)
764 {
765         struct rfkill *rfkill = to_rfkill(dev);
766
767         return sysfs_emit(buf, "0x%lx\n", rfkill->hard_block_reasons);
768 }
769 static DEVICE_ATTR_RO(hard_block_reasons);
770
771 static u8 user_state_from_blocked(unsigned long state)
772 {
773         if (state & RFKILL_BLOCK_HW)
774                 return RFKILL_USER_STATE_HARD_BLOCKED;
775         if (state & RFKILL_BLOCK_SW)
776                 return RFKILL_USER_STATE_SOFT_BLOCKED;
777
778         return RFKILL_USER_STATE_UNBLOCKED;
779 }
780
781 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
782                           char *buf)
783 {
784         struct rfkill *rfkill = to_rfkill(dev);
785
786         return sysfs_emit(buf, "%d\n", user_state_from_blocked(rfkill->state));
787 }
788
789 static ssize_t state_store(struct device *dev, struct device_attribute *attr,
790                            const char *buf, size_t count)
791 {
792         struct rfkill *rfkill = to_rfkill(dev);
793         unsigned long state;
794         int err;
795
796         if (!capable(CAP_NET_ADMIN))
797                 return -EPERM;
798
799         err = kstrtoul(buf, 0, &state);
800         if (err)
801                 return err;
802
803         if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
804             state != RFKILL_USER_STATE_UNBLOCKED)
805                 return -EINVAL;
806
807         mutex_lock(&rfkill_global_mutex);
808         rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
809         mutex_unlock(&rfkill_global_mutex);
810
811         return count;
812 }
813 static DEVICE_ATTR_RW(state);
814
815 static struct attribute *rfkill_dev_attrs[] = {
816         &dev_attr_name.attr,
817         &dev_attr_type.attr,
818         &dev_attr_index.attr,
819         &dev_attr_persistent.attr,
820         &dev_attr_state.attr,
821         &dev_attr_soft.attr,
822         &dev_attr_hard.attr,
823         &dev_attr_hard_block_reasons.attr,
824         NULL,
825 };
826 ATTRIBUTE_GROUPS(rfkill_dev);
827
828 static void rfkill_release(struct device *dev)
829 {
830         struct rfkill *rfkill = to_rfkill(dev);
831
832         kfree(rfkill);
833 }
834
835 static int rfkill_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
836 {
837         struct rfkill *rfkill = to_rfkill(dev);
838         unsigned long flags;
839         unsigned long reasons;
840         u32 state;
841         int error;
842
843         error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
844         if (error)
845                 return error;
846         error = add_uevent_var(env, "RFKILL_TYPE=%s",
847                                rfkill_types[rfkill->type]);
848         if (error)
849                 return error;
850         spin_lock_irqsave(&rfkill->lock, flags);
851         state = rfkill->state;
852         reasons = rfkill->hard_block_reasons;
853         spin_unlock_irqrestore(&rfkill->lock, flags);
854         error = add_uevent_var(env, "RFKILL_STATE=%d",
855                                user_state_from_blocked(state));
856         if (error)
857                 return error;
858         return add_uevent_var(env, "RFKILL_HW_BLOCK_REASON=0x%lx", reasons);
859 }
860
861 void rfkill_pause_polling(struct rfkill *rfkill)
862 {
863         BUG_ON(!rfkill);
864
865         if (!rfkill->ops->poll)
866                 return;
867
868         rfkill->polling_paused = true;
869         cancel_delayed_work_sync(&rfkill->poll_work);
870 }
871 EXPORT_SYMBOL(rfkill_pause_polling);
872
873 void rfkill_resume_polling(struct rfkill *rfkill)
874 {
875         BUG_ON(!rfkill);
876
877         if (!rfkill->ops->poll)
878                 return;
879
880         rfkill->polling_paused = false;
881
882         if (rfkill->suspended)
883                 return;
884
885         queue_delayed_work(system_power_efficient_wq,
886                            &rfkill->poll_work, 0);
887 }
888 EXPORT_SYMBOL(rfkill_resume_polling);
889
890 #ifdef CONFIG_PM_SLEEP
891 static int rfkill_suspend(struct device *dev)
892 {
893         struct rfkill *rfkill = to_rfkill(dev);
894
895         rfkill->suspended = true;
896         cancel_delayed_work_sync(&rfkill->poll_work);
897
898         return 0;
899 }
900
901 static int rfkill_resume(struct device *dev)
902 {
903         struct rfkill *rfkill = to_rfkill(dev);
904         bool cur;
905
906         rfkill->suspended = false;
907
908         if (!rfkill->registered)
909                 return 0;
910
911         if (!rfkill->persistent) {
912                 cur = !!(rfkill->state & RFKILL_BLOCK_SW);
913                 rfkill_set_block(rfkill, cur);
914         }
915
916         if (rfkill->ops->poll && !rfkill->polling_paused)
917                 queue_delayed_work(system_power_efficient_wq,
918                                    &rfkill->poll_work, 0);
919
920         return 0;
921 }
922
923 static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
924 #define RFKILL_PM_OPS (&rfkill_pm_ops)
925 #else
926 #define RFKILL_PM_OPS NULL
927 #endif
928
929 static struct class rfkill_class = {
930         .name           = "rfkill",
931         .dev_release    = rfkill_release,
932         .dev_groups     = rfkill_dev_groups,
933         .dev_uevent     = rfkill_dev_uevent,
934         .pm             = RFKILL_PM_OPS,
935 };
936
937 bool rfkill_blocked(struct rfkill *rfkill)
938 {
939         unsigned long flags;
940         u32 state;
941
942         spin_lock_irqsave(&rfkill->lock, flags);
943         state = rfkill->state;
944         spin_unlock_irqrestore(&rfkill->lock, flags);
945
946         return !!(state & RFKILL_BLOCK_ANY);
947 }
948 EXPORT_SYMBOL(rfkill_blocked);
949
950 bool rfkill_soft_blocked(struct rfkill *rfkill)
951 {
952         unsigned long flags;
953         u32 state;
954
955         spin_lock_irqsave(&rfkill->lock, flags);
956         state = rfkill->state;
957         spin_unlock_irqrestore(&rfkill->lock, flags);
958
959         return !!(state & RFKILL_BLOCK_SW);
960 }
961 EXPORT_SYMBOL(rfkill_soft_blocked);
962
963 struct rfkill * __must_check rfkill_alloc(const char *name,
964                                           struct device *parent,
965                                           const enum rfkill_type type,
966                                           const struct rfkill_ops *ops,
967                                           void *ops_data)
968 {
969         struct rfkill *rfkill;
970         struct device *dev;
971
972         if (WARN_ON(!ops))
973                 return NULL;
974
975         if (WARN_ON(!ops->set_block))
976                 return NULL;
977
978         if (WARN_ON(!name))
979                 return NULL;
980
981         if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
982                 return NULL;
983
984         rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
985         if (!rfkill)
986                 return NULL;
987
988         spin_lock_init(&rfkill->lock);
989         INIT_LIST_HEAD(&rfkill->node);
990         rfkill->type = type;
991         strcpy(rfkill->name, name);
992         rfkill->ops = ops;
993         rfkill->data = ops_data;
994
995         dev = &rfkill->dev;
996         dev->class = &rfkill_class;
997         dev->parent = parent;
998         device_initialize(dev);
999
1000         return rfkill;
1001 }
1002 EXPORT_SYMBOL(rfkill_alloc);
1003
1004 static void rfkill_poll(struct work_struct *work)
1005 {
1006         struct rfkill *rfkill;
1007
1008         rfkill = container_of(work, struct rfkill, poll_work.work);
1009
1010         /*
1011          * Poll hardware state -- driver will use one of the
1012          * rfkill_set{,_hw,_sw}_state functions and use its
1013          * return value to update the current status.
1014          */
1015         rfkill->ops->poll(rfkill, rfkill->data);
1016
1017         queue_delayed_work(system_power_efficient_wq,
1018                 &rfkill->poll_work,
1019                 round_jiffies_relative(POLL_INTERVAL));
1020 }
1021
1022 static void rfkill_uevent_work(struct work_struct *work)
1023 {
1024         struct rfkill *rfkill;
1025
1026         rfkill = container_of(work, struct rfkill, uevent_work);
1027
1028         mutex_lock(&rfkill_global_mutex);
1029         rfkill_event(rfkill);
1030         mutex_unlock(&rfkill_global_mutex);
1031 }
1032
1033 static void rfkill_sync_work(struct work_struct *work)
1034 {
1035         struct rfkill *rfkill;
1036         bool cur;
1037
1038         rfkill = container_of(work, struct rfkill, sync_work);
1039
1040         mutex_lock(&rfkill_global_mutex);
1041         cur = rfkill_global_states[rfkill->type].cur;
1042         rfkill_set_block(rfkill, cur);
1043         mutex_unlock(&rfkill_global_mutex);
1044 }
1045
1046 int __must_check rfkill_register(struct rfkill *rfkill)
1047 {
1048         static unsigned long rfkill_no;
1049         struct device *dev;
1050         int error;
1051
1052         if (!rfkill)
1053                 return -EINVAL;
1054
1055         dev = &rfkill->dev;
1056
1057         mutex_lock(&rfkill_global_mutex);
1058
1059         if (rfkill->registered) {
1060                 error = -EALREADY;
1061                 goto unlock;
1062         }
1063
1064         rfkill->idx = rfkill_no;
1065         dev_set_name(dev, "rfkill%lu", rfkill_no);
1066         rfkill_no++;
1067
1068         list_add_tail(&rfkill->node, &rfkill_list);
1069
1070         error = device_add(dev);
1071         if (error)
1072                 goto remove;
1073
1074         error = rfkill_led_trigger_register(rfkill);
1075         if (error)
1076                 goto devdel;
1077
1078         rfkill->registered = true;
1079
1080         INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
1081         INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
1082         INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
1083
1084         if (rfkill->ops->poll)
1085                 queue_delayed_work(system_power_efficient_wq,
1086                         &rfkill->poll_work,
1087                         round_jiffies_relative(POLL_INTERVAL));
1088
1089         if (!rfkill->persistent || rfkill_epo_lock_active) {
1090                 schedule_work(&rfkill->sync_work);
1091         } else {
1092 #ifdef CONFIG_RFKILL_INPUT
1093                 bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
1094
1095                 if (!atomic_read(&rfkill_input_disabled))
1096                         __rfkill_switch_all(rfkill->type, soft_blocked);
1097 #endif
1098         }
1099
1100         rfkill_global_led_trigger_event();
1101         rfkill_send_events(rfkill, RFKILL_OP_ADD);
1102
1103         mutex_unlock(&rfkill_global_mutex);
1104         return 0;
1105
1106  devdel:
1107         device_del(&rfkill->dev);
1108  remove:
1109         list_del_init(&rfkill->node);
1110  unlock:
1111         mutex_unlock(&rfkill_global_mutex);
1112         return error;
1113 }
1114 EXPORT_SYMBOL(rfkill_register);
1115
1116 void rfkill_unregister(struct rfkill *rfkill)
1117 {
1118         BUG_ON(!rfkill);
1119
1120         if (rfkill->ops->poll)
1121                 cancel_delayed_work_sync(&rfkill->poll_work);
1122
1123         cancel_work_sync(&rfkill->uevent_work);
1124         cancel_work_sync(&rfkill->sync_work);
1125
1126         rfkill->registered = false;
1127
1128         device_del(&rfkill->dev);
1129
1130         mutex_lock(&rfkill_global_mutex);
1131         rfkill_send_events(rfkill, RFKILL_OP_DEL);
1132         list_del_init(&rfkill->node);
1133         rfkill_global_led_trigger_event();
1134         mutex_unlock(&rfkill_global_mutex);
1135
1136         rfkill_led_trigger_unregister(rfkill);
1137 }
1138 EXPORT_SYMBOL(rfkill_unregister);
1139
1140 void rfkill_destroy(struct rfkill *rfkill)
1141 {
1142         if (rfkill)
1143                 put_device(&rfkill->dev);
1144 }
1145 EXPORT_SYMBOL(rfkill_destroy);
1146
1147 static int rfkill_fop_open(struct inode *inode, struct file *file)
1148 {
1149         struct rfkill_data *data;
1150         struct rfkill *rfkill;
1151         struct rfkill_int_event *ev, *tmp;
1152
1153         data = kzalloc(sizeof(*data), GFP_KERNEL);
1154         if (!data)
1155                 return -ENOMEM;
1156
1157         data->max_size = RFKILL_EVENT_SIZE_V1;
1158
1159         INIT_LIST_HEAD(&data->events);
1160         mutex_init(&data->mtx);
1161         init_waitqueue_head(&data->read_wait);
1162
1163         mutex_lock(&rfkill_global_mutex);
1164         mutex_lock(&data->mtx);
1165         /*
1166          * start getting events from elsewhere but hold mtx to get
1167          * startup events added first
1168          */
1169
1170         list_for_each_entry(rfkill, &rfkill_list, node) {
1171                 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1172                 if (!ev)
1173                         goto free;
1174                 rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
1175                 list_add_tail(&ev->list, &data->events);
1176         }
1177         list_add(&data->list, &rfkill_fds);
1178         mutex_unlock(&data->mtx);
1179         mutex_unlock(&rfkill_global_mutex);
1180
1181         file->private_data = data;
1182
1183         return stream_open(inode, file);
1184
1185  free:
1186         mutex_unlock(&data->mtx);
1187         mutex_unlock(&rfkill_global_mutex);
1188         mutex_destroy(&data->mtx);
1189         list_for_each_entry_safe(ev, tmp, &data->events, list)
1190                 kfree(ev);
1191         kfree(data);
1192         return -ENOMEM;
1193 }
1194
1195 static __poll_t rfkill_fop_poll(struct file *file, poll_table *wait)
1196 {
1197         struct rfkill_data *data = file->private_data;
1198         __poll_t res = EPOLLOUT | EPOLLWRNORM;
1199
1200         poll_wait(file, &data->read_wait, wait);
1201
1202         mutex_lock(&data->mtx);
1203         if (!list_empty(&data->events))
1204                 res = EPOLLIN | EPOLLRDNORM;
1205         mutex_unlock(&data->mtx);
1206
1207         return res;
1208 }
1209
1210 static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
1211                                size_t count, loff_t *pos)
1212 {
1213         struct rfkill_data *data = file->private_data;
1214         struct rfkill_int_event *ev;
1215         unsigned long sz;
1216         int ret;
1217
1218         mutex_lock(&data->mtx);
1219
1220         while (list_empty(&data->events)) {
1221                 if (file->f_flags & O_NONBLOCK) {
1222                         ret = -EAGAIN;
1223                         goto out;
1224                 }
1225                 mutex_unlock(&data->mtx);
1226                 /* since we re-check and it just compares pointers,
1227                  * using !list_empty() without locking isn't a problem
1228                  */
1229                 ret = wait_event_interruptible(data->read_wait,
1230                                                !list_empty(&data->events));
1231                 mutex_lock(&data->mtx);
1232
1233                 if (ret)
1234                         goto out;
1235         }
1236
1237         ev = list_first_entry(&data->events, struct rfkill_int_event,
1238                                 list);
1239
1240         sz = min_t(unsigned long, sizeof(ev->ev), count);
1241         sz = min_t(unsigned long, sz, data->max_size);
1242         ret = sz;
1243         if (copy_to_user(buf, &ev->ev, sz))
1244                 ret = -EFAULT;
1245
1246         list_del(&ev->list);
1247         kfree(ev);
1248  out:
1249         mutex_unlock(&data->mtx);
1250         return ret;
1251 }
1252
1253 static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
1254                                 size_t count, loff_t *pos)
1255 {
1256         struct rfkill_data *data = file->private_data;
1257         struct rfkill *rfkill;
1258         struct rfkill_event_ext ev;
1259         int ret;
1260
1261         /* we don't need the 'hard' variable but accept it */
1262         if (count < RFKILL_EVENT_SIZE_V1 - 1)
1263                 return -EINVAL;
1264
1265         /*
1266          * Copy as much data as we can accept into our 'ev' buffer,
1267          * but tell userspace how much we've copied so it can determine
1268          * our API version even in a write() call, if it cares.
1269          */
1270         count = min(count, sizeof(ev));
1271         count = min_t(size_t, count, data->max_size);
1272         if (copy_from_user(&ev, buf, count))
1273                 return -EFAULT;
1274
1275         if (ev.type >= NUM_RFKILL_TYPES)
1276                 return -EINVAL;
1277
1278         mutex_lock(&rfkill_global_mutex);
1279
1280         switch (ev.op) {
1281         case RFKILL_OP_CHANGE_ALL:
1282                 rfkill_update_global_state(ev.type, ev.soft);
1283                 list_for_each_entry(rfkill, &rfkill_list, node)
1284                         if (rfkill->type == ev.type ||
1285                             ev.type == RFKILL_TYPE_ALL)
1286                                 rfkill_set_block(rfkill, ev.soft);
1287                 ret = 0;
1288                 break;
1289         case RFKILL_OP_CHANGE:
1290                 list_for_each_entry(rfkill, &rfkill_list, node)
1291                         if (rfkill->idx == ev.idx &&
1292                             (rfkill->type == ev.type ||
1293                              ev.type == RFKILL_TYPE_ALL))
1294                                 rfkill_set_block(rfkill, ev.soft);
1295                 ret = 0;
1296                 break;
1297         default:
1298                 ret = -EINVAL;
1299                 break;
1300         }
1301
1302         mutex_unlock(&rfkill_global_mutex);
1303
1304         return ret ?: count;
1305 }
1306
1307 static int rfkill_fop_release(struct inode *inode, struct file *file)
1308 {
1309         struct rfkill_data *data = file->private_data;
1310         struct rfkill_int_event *ev, *tmp;
1311
1312         mutex_lock(&rfkill_global_mutex);
1313         list_del(&data->list);
1314         mutex_unlock(&rfkill_global_mutex);
1315
1316         mutex_destroy(&data->mtx);
1317         list_for_each_entry_safe(ev, tmp, &data->events, list)
1318                 kfree(ev);
1319
1320 #ifdef CONFIG_RFKILL_INPUT
1321         if (data->input_handler)
1322                 if (atomic_dec_return(&rfkill_input_disabled) == 0)
1323                         printk(KERN_DEBUG "rfkill: input handler enabled\n");
1324 #endif
1325
1326         kfree(data);
1327
1328         return 0;
1329 }
1330
1331 static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
1332                              unsigned long arg)
1333 {
1334         struct rfkill_data *data = file->private_data;
1335         int ret = -ENOSYS;
1336         u32 size;
1337
1338         if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
1339                 return -ENOSYS;
1340
1341         mutex_lock(&data->mtx);
1342         switch (_IOC_NR(cmd)) {
1343 #ifdef CONFIG_RFKILL_INPUT
1344         case RFKILL_IOC_NOINPUT:
1345                 if (!data->input_handler) {
1346                         if (atomic_inc_return(&rfkill_input_disabled) == 1)
1347                                 printk(KERN_DEBUG "rfkill: input handler disabled\n");
1348                         data->input_handler = true;
1349                 }
1350                 ret = 0;
1351                 break;
1352 #endif
1353         case RFKILL_IOC_MAX_SIZE:
1354                 if (get_user(size, (__u32 __user *)arg)) {
1355                         ret = -EFAULT;
1356                         break;
1357                 }
1358                 if (size < RFKILL_EVENT_SIZE_V1 || size > U8_MAX) {
1359                         ret = -EINVAL;
1360                         break;
1361                 }
1362                 data->max_size = size;
1363                 ret = 0;
1364                 break;
1365         default:
1366                 break;
1367         }
1368         mutex_unlock(&data->mtx);
1369
1370         return ret;
1371 }
1372
1373 static const struct file_operations rfkill_fops = {
1374         .owner          = THIS_MODULE,
1375         .open           = rfkill_fop_open,
1376         .read           = rfkill_fop_read,
1377         .write          = rfkill_fop_write,
1378         .poll           = rfkill_fop_poll,
1379         .release        = rfkill_fop_release,
1380         .unlocked_ioctl = rfkill_fop_ioctl,
1381         .compat_ioctl   = compat_ptr_ioctl,
1382         .llseek         = no_llseek,
1383 };
1384
1385 #define RFKILL_NAME "rfkill"
1386
1387 static struct miscdevice rfkill_miscdev = {
1388         .fops   = &rfkill_fops,
1389         .name   = RFKILL_NAME,
1390         .minor  = RFKILL_MINOR,
1391 };
1392
1393 static int __init rfkill_init(void)
1394 {
1395         int error;
1396
1397         rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);
1398
1399         error = class_register(&rfkill_class);
1400         if (error)
1401                 goto error_class;
1402
1403         error = misc_register(&rfkill_miscdev);
1404         if (error)
1405                 goto error_misc;
1406
1407         error = rfkill_global_led_trigger_register();
1408         if (error)
1409                 goto error_led_trigger;
1410
1411 #ifdef CONFIG_RFKILL_INPUT
1412         error = rfkill_handler_init();
1413         if (error)
1414                 goto error_input;
1415 #endif
1416
1417         return 0;
1418
1419 #ifdef CONFIG_RFKILL_INPUT
1420 error_input:
1421         rfkill_global_led_trigger_unregister();
1422 #endif
1423 error_led_trigger:
1424         misc_deregister(&rfkill_miscdev);
1425 error_misc:
1426         class_unregister(&rfkill_class);
1427 error_class:
1428         return error;
1429 }
1430 subsys_initcall(rfkill_init);
1431
1432 static void __exit rfkill_exit(void)
1433 {
1434 #ifdef CONFIG_RFKILL_INPUT
1435         rfkill_handler_exit();
1436 #endif
1437         rfkill_global_led_trigger_unregister();
1438         misc_deregister(&rfkill_miscdev);
1439         class_unregister(&rfkill_class);
1440 }
1441 module_exit(rfkill_exit);
1442
1443 MODULE_ALIAS_MISCDEV(RFKILL_MINOR);
1444 MODULE_ALIAS("devname:" RFKILL_NAME);