aboutsummaryrefslogtreecommitdiffstats
path: root/net/rfkill/rfkill-input.c
blob: 84efde97c5a773fe027d051cb3522e55534b8eb1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
/*
 * Input layer to RF Kill interface connector
 *
 * Copyright (c) 2007 Dmitry Torokhov
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/init.h>
#include <linux/rfkill.h>
#include <linux/sched.h>

#include "rfkill-input.h"

MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
MODULE_DESCRIPTION("Input layer to RF switch connector");
MODULE_LICENSE("GPL");

enum rfkill_input_master_mode {
	RFKILL_INPUT_MASTER_DONOTHING = 0,
	RFKILL_INPUT_MASTER_RESTORE = 1,
	RFKILL_INPUT_MASTER_UNBLOCKALL = 2,
	RFKILL_INPUT_MASTER_MAX,	/* marker */
};

/* Delay (in ms) between consecutive switch ops */
#define RFKILL_OPS_DELAY 200

static enum rfkill_input_master_mode rfkill_master_switch_mode =
					RFKILL_INPUT_MASTER_UNBLOCKALL;
module_param_named(master_switch_mode, rfkill_master_switch_mode, uint, 0);
MODULE_PARM_DESC(master_switch_mode,
	"SW_RFKILL_ALL ON should: 0=do nothing; 1=restore; 2=unblock all");

enum rfkill_global_sched_op {
	RFKILL_GLOBAL_OP_EPO = 0,
	RFKILL_GLOBAL_OP_RESTORE,
	RFKILL_GLOBAL_OP_UNLOCK,
	RFKILL_GLOBAL_OP_UNBLOCK,
};

/*
 * Currently, the code marked with RFKILL_NEED_SWSET is inactive.
 * If handling of EV_SW SW_WLAN/WWAN/BLUETOOTH/etc is needed in the
 * future, when such events are added, that code will be necessary.
 */

struct rfkill_task {
	struct delayed_work dwork;

	/* ensures that task is serialized */
	struct mutex mutex;

	/* protects everything below */
	spinlock_t lock;

	/* pending regular switch operations (1=pending) */
	unsigned long sw_pending[BITS_TO_LONGS(RFKILL_TYPE_MAX)];

#ifdef RFKILL_NEED_SWSET
	/* set operation pending (1=pending) */
	unsigned long sw_setpending[BITS_TO_LONGS(RFKILL_TYPE_MAX)];

	/* desired state for pending set operation (1=unblock) */
	unsigned long sw_newstate[BITS_TO_LONGS(RFKILL_TYPE_MAX)];
#endif

	/* should the state be complemented (1=yes) */
	unsigned long sw_togglestate[BITS_TO_LONGS(RFKILL_TYPE_MAX)];

	bool global_op_pending;
	enum rfkill_global_sched_op op;

	/* last time it was scheduled */
	unsigned long last_scheduled;
};

static void __rfkill_handle_global_op(enum rfkill_global_sched_op op)
{
	unsigned int i;

	switch (op) {
	case RFKILL_GLOBAL_OP_EPO:
		rfkill_epo();
		break;
	case RFKILL_GLOBAL_OP_RESTORE:
		rfkill_restore_states();
		break;
	case RFKILL_GLOBAL_OP_UNLOCK:
		rfkill_remove_epo_lock();
		break;
	case RFKILL_GLOBAL_OP_UNBLOCK:
		rfkill_remove_epo_lock();
		for (i = 0; i < RFKILL_TYPE_MAX; i++)
			rfkill_switch_all(i, RFKILL_STATE_UNBLOCKED);
		break;
	default:
		/* memory corruption or bug, fail safely */
		rfkill_epo();
		WARN(1, "Unknown requested operation %d! "
			"rfkill Emergency Power Off activated\n",
			op);
	}
}

#ifdef RFKILL_NEED_SWSET
static void __rfkill_handle_normal_op(const enum rfkill_type type,
			const bool sp, const bool s, const bool c)
{
	enum rfkill_state state;

	if (sp)
		state = (s) ? RFKILL_STATE_UNBLOCKED :
			      RFKILL_STATE_SOFT_BLOCKED;
	else
		state = rfkill_get_global_state(type);

	if (c)
		state = rfkill_state_complement(state);

	rfkill_switch_all(type, state);
}
#else
static void __rfkill_handle_normal_op(const enum rfkill_type type,
			const bool c)
{
	enum rfkill_state state;

	state = rfkill_get_global_state(type);
	if (c)
		state = rfkill_state_complement(state);

	rfkill_switch_all(type, state);
}
#endif

static void rfkill_task_handler(struct work_struct *work)
{
	struct rfkill_task *task = container_of(work,
					struct rfkill_task, dwork.work);
	bool doit = true;

	mutex_lock(&task->mutex);

	spin_lock_irq(&task->lock);
	while (doit) {
		if (task->global_op_pending) {
			enum rfkill_global_sched_op op = task->op;
			task->global_op_pending = false;
			memset(task->sw_pending, 0, sizeof(task->sw_pending));
			spin_unlock_irq(&task->lock);

			__rfkill_handle_global_op(op);

			/* make sure we do at least one pass with
			 * !task->global_op_pending */
			spin_lock_irq(&task->lock);
			continue;
		} else if (!rfkill_is_epo_lock_active()) {
			unsigned int i = 0;

			while (!task->global_op_pending &&
						i < RFKILL_TYPE_MAX) {
				if (test_and_clear_bit(i, task->sw_pending)) {
					bool c;
#ifdef RFKILL_NEED_SWSET
					bool sp, s;
					sp = test_and_clear_bit(i,
							task->sw_setpending);
					s = test_bit(i, task->sw_newstate);
#endif
					c = test_and_clear_bit(i,
							task->sw_togglestate);
					spin_unlock_irq(&task->lock);

#ifdef RFKILL_NEED_SWSET
					__rfkill_handle_normal_op(i, sp, s, c);
#else
					__rfkill_handle_normal_op(i, c);
#endif

					spin_lock_irq(&task->lock);
				}
				i++;
			}
		}
		doit = task->global_op_pending;
	}
	spin_unlock_irq(&task->lock);

	mutex_unlock(&task->mutex);
}

static struct rfkill_task rfkill_task = {
	.dwork = __DELAYED_WORK_INITIALIZER(rfkill_task.dwork,
				rfkill_task_handler),
	.mutex = __MUTEX_INITIALIZER(rfkill_task.mutex),
	.lock = __SPIN_LOCK_UNLOCKED(rfkill_task.lock),
};

static unsigned long rfkill_ratelimit(const unsigned long last)
{
	const unsigned long delay = msecs_to_jiffies(RFKILL_OPS_DELAY);
	return (time_after(jiffies, last + delay)) ? 0 : delay;
}

static void rfkill_schedule_ratelimited(void)
{
	if (!delayed_work_pending(&rfkill_task.dwork)) {
		schedule_delayed_work(&rfkill_task.dwork,
				rfkill_ratelimit(rfkill_task.last_scheduled));
		rfkill_task.last_scheduled = jiffies;
	}
}

static void rfkill_schedule_global_op(enum rfkill_global_sched_op op)
{
	unsigned long flags;

	spin_lock_irqsave(&rfkill_task.lock, flags);
	rfkill_task.op = op;
	rfkill_task.global_op_pending = true;
	if (op == RFKILL_GLOBAL_OP_EPO && !rfkill_is_epo_lock_active()) {
		/* bypass the limiter for EPO */
		cancel_delayed_work(&rfkill_task.dwork);
		schedule_delayed_work(&rfkill_task.dwork, 0);
		rfkill_task.last_scheduled = jiffies;
	} else
		rfkill_schedule_ratelimited();
	spin_unlock_irqrestore(&rfkill_task.lock, flags);
}

#ifdef RFKILL_NEED_SWSET
/* Use this if you need to add EV_SW SW_WLAN/WWAN/BLUETOOTH/etc handling */

static void rfkill_schedule_set(enum rfkill_type type,
				enum rfkill_state desired_state)
{
	unsigned long flags;

	if (rfkill_is_epo_lock_active())
		return;

	spin_lock_irqsave(&rfkill_task.lock, flags);
	if (!rfkill_task.global_op_pending) {
		set_bit(type, rfkill_task.sw_pending);
		set_bit(type, rfkill_task.sw_setpending);
		clear_bit(type, rfkill_task.sw_togglestate);
		if (desired_state)
			set_bit(type,  rfkill_task.sw_newstate);
		else
			clear_bit(type, rfkill_task.sw_newstate);
		rfkill_schedule_ratelimited();
	}
	spin_unlock_irqrestore(&rfkill_task.lock, flags);
}
#endif

static void rfkill_schedule_toggle(enum rfkill_type type)
{
	unsigned long flags;

	if (rfkill_is_epo_lock_active())
		return;

	spin_lock_irqsave(&rfkill_task.lock, flags);
	if (!rfkill_task.global_op_pending) {
		set_bit(type, rfkill_task.sw_pending);
		change_bit(type, rfkill_task.sw_togglestate);
		rfkill_schedule_ratelimited();
	}
	spin_unlock_irqrestore(&rfkill_task.lock, flags);
}

static void rfkill_schedule_evsw_rfkillall(int state)
{
	if (state) {
		switch (rfkill_master_switch_mode) {
		case RFKILL_INPUT_MASTER_UNBLOCKALL:
			rfkill_schedule_global_op(RFKILL_GLOBAL_OP_UNBLOCK);
			break;
		case RFKILL_INPUT_MASTER_RESTORE:
			rfkill_schedule_global_op(RFKILL_GLOBAL_OP_RESTORE);
			break;
		case RFKILL_INPUT_MASTER_DONOTHING:
			rfkill_schedule_global_op(RFKILL_GLOBAL_OP_UNLOCK);
			break;
		default:
			/* memory corruption or driver bug! fail safely */
			rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO);
			WARN(1, "Unknown rfkill_master_switch_mode (%d), "
				"driver bug or memory corruption detected!\n",
				rfkill_master_switch_mode);
			break;
		}
	} else
		rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO);
}

static void rfkill_event(struct input_handle *handle, unsigned int type,
			unsigned int code, int data)
{
	if (type == EV_KEY && data == 1) {
		enum rfkill_type t;

		switch (code) {
		case KEY_WLAN:
			t = RFKILL_TYPE_WLAN;
			break;
		case KEY_BLUETOOTH:
			t = RFKILL_TYPE_BLUETOOTH;
			break;
		case KEY_UWB:
			t = RFKILL_TYPE_UWB;
			break;
		case KEY_WIMAX:
			t = RFKILL_TYPE_WIMAX;
			break;
		default:
			return;
		}
		rfkill_schedule_toggle(t);
		return;
	} else if (type == EV_SW) {
		switch (code) {
		case SW_RFKILL_ALL:
			rfkill_schedule_evsw_rfkillall(data);
			return;
		default:
			return;
		}
	}
}

static int rfkill_connect(struct input_handler *handler, struct input_dev *dev,
			  const struct input_device_id *id)
{
	struct input_handle *handle;
	int error;

	handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
	if (!handle)
		return -ENOMEM;

	handle->dev = dev;
	handle->handler = handler;
	handle->name = "rfkill";

	/* causes rfkill_start() to be called */
	error = input_register_handle(handle);
	if (error)
		goto err_free_handle;

	error = input_open_device(handle);
	if (error)
		goto err_unregister_handle;

	return 0;

 err_unregister_handle:
	input_unregister_handle(handle);
 err_free_handle:
	kfree(handle);
	return error;
}

static void rfkill_start(struct input_handle *handle)
{
	/* Take event_lock to guard against configuration changes, we
	 * should be able to deal with concurrency with rfkill_event()
	 * just fine (which event_lock will also avoid). */
	spin_lock_irq(&handle->dev->event_lock);

	if (test_bit(EV_SW, handle->dev->evbit)) {
		if (test_bit(SW_RFKILL_ALL, handle->dev->swbit))
			rfkill_schedule_evsw_rfkillall(test_bit(SW_RFKILL_ALL,
							handle->dev->sw));
		/* add resync for further EV_SW events here */
	}

	spin_unlock_irq(&handle->dev->event_lock);
}

static void rfkill_disconnect(struct input_handle *handle)
{
	input_close_device(handle);
	input_unregister_handle(handle);
	kfree(handle);
}

static const struct input_device_id rfkill_ids[] = {
	{
		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
		.evbit = { BIT_MASK(EV_KEY) },
		.keybit = { [BIT_WORD(KEY_WLAN)] = BIT_MASK(KEY_WLAN) },
	},
	{
		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
		.evbit = { BIT_MASK(EV_KEY) },
		.keybit = { [BIT_WORD(KEY_BLUETOOTH)] = BIT_MASK(KEY_BLUETOOTH) },
	},
	{
		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
		.evbit = { BIT_MASK(EV_KEY) },
		.keybit = { [BIT_WORD(KEY_UWB)] = BIT_MASK(KEY_UWB) },
	},
	{
		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
		.evbit = { BIT_MASK(EV_KEY) },
		.keybit = { [BIT_WORD(KEY_WIMAX)] = BIT_MASK(KEY_WIMAX) },
	},
	{
		.flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_SWBIT,
		.evbit = { BIT(EV_SW) },
		.swbit = { [BIT_WORD(SW_RFKILL_ALL)] = BIT_MASK(SW_RFKILL_ALL) },
	},
	{ }
};

static struct input_handler rfkill_handler = {
	.event =	rfkill_event,
	.connect =	rfkill_connect,
	.disconnect =	rfkill_disconnect,
	.start =	rfkill_start,
	.name =		"rfkill",
	.id_table =	rfkill_ids,
};

static int __init rfkill_handler_init(void)
{
	if (rfkill_master_switch_mode >= RFKILL_INPUT_MASTER_MAX)
		return -EINVAL;

	/*
	 * The penalty to not doing this is a possible RFKILL_OPS_DELAY delay
	 * at the first use.  Acceptable, but if we can avoid it, why not?
	 */
	rfkill_task.last_scheduled =
			jiffies - msecs_to_jiffies(RFKILL_OPS_DELAY) - 1;
	return input_register_handler(&rfkill_handler);
}

static void __exit rfkill_handler_exit(void)
{
	input_unregister_handler(&rfkill_handler);
	cancel_delayed_work_sync(&rfkill_task.dwork);
	rfkill_remove_epo_lock();
}

module_init(rfkill_handler_init);
module_exit(rfkill_handler_exit);