aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/media/rc/rc-ir-raw.c
blob: dd47fe567f03561bef0a6a87bdc20b574b990972 (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
/* rc-ir-raw.c - handle IR pulse/space events
 *
 * Copyright (C) 2010 by Mauro Carvalho Chehab
 *
 * This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation version 2 of the License.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 */

#include <linux/export.h>
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/kmod.h>
#include <linux/sched.h>
#include <linux/freezer.h>
#include "rc-core-priv.h"

/* Define the max number of pulse/space transitions to buffer */
#define MAX_IR_EVENT_SIZE      512

/* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */
static LIST_HEAD(ir_raw_client_list);

/* Used to handle IR raw handler extensions */
static DEFINE_MUTEX(ir_raw_handler_lock);
static LIST_HEAD(ir_raw_handler_list);
static u64 available_protocols;

static int ir_raw_event_thread(void *data)
{
	struct ir_raw_event ev;
	struct ir_raw_handler *handler;
	struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data;
	int retval;

	while (!kthread_should_stop()) {

		spin_lock_irq(&raw->lock);
		retval = kfifo_len(&raw->kfifo);

		if (retval < sizeof(ev)) {
			set_current_state(TASK_INTERRUPTIBLE);

			if (kthread_should_stop())
				set_current_state(TASK_RUNNING);

			spin_unlock_irq(&raw->lock);
			schedule();
			continue;
		}

		retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));
		spin_unlock_irq(&raw->lock);

		mutex_lock(&ir_raw_handler_lock);
		list_for_each_entry(handler, &ir_raw_handler_list, list)
			handler->decode(raw->dev, ev);
		raw->prev_ev = ev;
		mutex_unlock(&ir_raw_handler_lock);
	}

	return 0;
}

/**
 * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
 * @dev:	the struct rc_dev device descriptor
 * @ev:		the struct ir_raw_event descriptor of the pulse/space
 *
 * This routine (which may be called from an interrupt context) stores a
 * pulse/space duration for the raw ir decoding state machines. Pulses are
 * signalled as positive values and spaces as negative values. A zero value
 * will reset the decoding state machines.
 */
int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev)
{
	if (!dev->raw)
		return -EINVAL;

	IR_dprintk(2, "sample: (%05dus %s)\n",
		   TO_US(ev->duration), TO_STR(ev->pulse));

	if (kfifo_in(&dev->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
		return -ENOMEM;

	return 0;
}
EXPORT_SYMBOL_GPL(ir_raw_event_store);

/**
 * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
 * @dev:	the struct rc_dev device descriptor
 * @type:	the type of the event that has occurred
 *
 * This routine (which may be called from an interrupt context) is used to
 * store the beginning of an ir pulse or space (or the start/end of ir
 * reception) for the raw ir decoding state machines. This is used by
 * hardware which does not provide durations directly but only interrupts
 * (or similar events) on state change.
 */
int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type)
{
	ktime_t			now;
	s64			delta; /* ns */
	DEFINE_IR_RAW_EVENT(ev);
	int			rc = 0;
	int			delay;

	if (!dev->raw)
		return -EINVAL;

	now = ktime_get();
	delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event));
	delay = MS_TO_NS(dev->input_dev->rep[REP_DELAY]);

	/* Check for a long duration since last event or if we're
	 * being called for the first time, note that delta can't
	 * possibly be negative.
	 */
	if (delta > delay || !dev->raw->last_type)
		type |= IR_START_EVENT;
	else
		ev.duration = delta;

	if (type & IR_START_EVENT)
		ir_raw_event_reset(dev);
	else if (dev->raw->last_type & IR_SPACE) {
		ev.pulse = false;
		rc = ir_raw_event_store(dev, &ev);
	} else if (dev->raw->last_type & IR_PULSE) {
		ev.pulse = true;
		rc = ir_raw_event_store(dev, &ev);
	} else
		return 0;

	dev->raw->last_event = now;
	dev->raw->last_type = type;
	return rc;
}
EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);

/**
 * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing
 * @dev:	the struct rc_dev device descriptor
 * @type:	the type of the event that has occurred
 *
 * This routine (which may be called from an interrupt context) works
 * in similar manner to ir_raw_event_store_edge.
 * This routine is intended for devices with limited internal buffer
 * It automerges samples of same type, and handles timeouts. Returns non-zero
 * if the event was added, and zero if the event was ignored due to idle
 * processing.
 */
int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev)
{
	if (!dev->raw)
		return -EINVAL;

	/* Ignore spaces in idle mode */
	if (dev->idle && !ev->pulse)
		return 0;
	else if (dev->idle)
		ir_raw_event_set_idle(dev, false);

	if (!dev->raw->this_ev.duration)
		dev->raw->this_ev = *ev;
	else if (ev->pulse == dev->raw->this_ev.pulse)
		dev->raw->this_ev.duration += ev->duration;
	else {
		ir_raw_event_store(dev, &dev->raw->this_ev);
		dev->raw->this_ev = *ev;
	}

	/* Enter idle mode if nessesary */
	if (!ev->pulse && dev->timeout &&
	    dev->raw->this_ev.duration >= dev->timeout)
		ir_raw_event_set_idle(dev, true);

	return 1;
}
EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter);

/**
 * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
 * @dev:	the struct rc_dev device descriptor
 * @idle:	whether the device is idle or not
 */
void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
{
	if (!dev->raw)
		return;

	IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave");

	if (idle) {
		dev->raw->this_ev.timeout = true;
		ir_raw_event_store(dev, &dev->raw->this_ev);
		init_ir_raw_event(&dev->raw->this_ev);
	}

	if (dev->s_idle)
		dev->s_idle(dev, idle);

	dev->idle = idle;
}
EXPORT_SYMBOL_GPL(ir_raw_event_set_idle);

/**
 * ir_raw_event_handle() - schedules the decoding of stored ir data
 * @dev:	the struct rc_dev device descriptor
 *
 * This routine will tell rc-core to start decoding stored ir data.
 */
void ir_raw_event_handle(struct rc_dev *dev)
{
	unsigned long flags;

	if (!dev->raw)
		return;

	spin_lock_irqsave(&dev->raw->lock, flags);
	wake_up_process(dev->raw->thread);
	spin_unlock_irqrestore(&dev->raw->lock, flags);
}
EXPORT_SYMBOL_GPL(ir_raw_event_handle);

/* used internally by the sysfs interface */
u64
ir_raw_get_allowed_protocols(void)
{
	u64 protocols;
	mutex_lock(&ir_raw_handler_lock);
	protocols = available_protocols;
	mutex_unlock(&ir_raw_handler_lock);
	return protocols;
}

static int change_protocol(struct rc_dev *dev, u64 *rc_type)
{
	/* the caller will update dev->enabled_protocols */
	return 0;
}

/**
 * ir_raw_encode_scancode() - Encode a scancode as raw events
 *
 * @protocols:		permitted protocols
 * @scancode:		scancode filter describing a single scancode
 * @events:		array of raw events to write into
 * @max:		max number of raw events
 *
 * Attempts to encode the scancode as raw events.
 *
 * Returns:	The number of events written.
 *		-ENOBUFS if there isn't enough space in the array to fit the
 *		encoding. In this case all @max events will have been written.
 *		-EINVAL if the scancode is ambiguous or invalid, or if no
 *		compatible encoder was found.
 */
int ir_raw_encode_scancode(u64 protocols,
			   const struct rc_scancode_filter *scancode,
			   struct ir_raw_event *events, unsigned int max)
{
	struct ir_raw_handler *handler;
	int ret = -EINVAL;

	mutex_lock(&ir_raw_handler_lock);
	list_for_each_entry(handler, &ir_raw_handler_list, list) {
		if (handler->protocols & protocols && handler->encode) {
			ret = handler->encode(protocols, scancode, events, max);
			if (ret >= 0 || ret == -ENOBUFS)
				break;
		}
	}
	mutex_unlock(&ir_raw_handler_lock);

	return ret;
}
EXPORT_SYMBOL(ir_raw_encode_scancode);

/*
 * Used to (un)register raw event clients
 */
int ir_raw_event_register(struct rc_dev *dev)
{
	int rc;
	struct ir_raw_handler *handler;

	if (!dev)
		return -EINVAL;

	dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL);
	if (!dev->raw)
		return -ENOMEM;

	dev->raw->dev = dev;
	dev->change_protocol = change_protocol;
	rc = kfifo_alloc(&dev->raw->kfifo,
			 sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE,
			 GFP_KERNEL);
	if (rc < 0)
		goto out;

	spin_lock_init(&dev->raw->lock);
	dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw,
				       "rc%ld", dev->devno);

	if (IS_ERR(dev->raw->thread)) {
		rc = PTR_ERR(dev->raw->thread);
		goto out;
	}

	mutex_lock(&ir_raw_handler_lock);
	list_add_tail(&dev->raw->list, &ir_raw_client_list);
	list_for_each_entry(handler, &ir_raw_handler_list, list)
		if (handler->raw_register)
			handler->raw_register(dev);
	mutex_unlock(&ir_raw_handler_lock);

	return 0;

out:
	kfree(dev->raw);
	dev->raw = NULL;
	return rc;
}

void ir_raw_event_unregister(struct rc_dev *dev)
{
	struct ir_raw_handler *handler;

	if (!dev || !dev->raw)
		return;

	kthread_stop(dev->raw->thread);

	mutex_lock(&ir_raw_handler_lock);
	list_del(&dev->raw->list);
	list_for_each_entry(handler, &ir_raw_handler_list, list)
		if (handler->raw_unregister)
			handler->raw_unregister(dev);
	mutex_unlock(&ir_raw_handler_lock);

	kfifo_free(&dev->raw->kfifo);
	kfree(dev->raw);
	dev->raw = NULL;
}

/*
 * Extension interface - used to register the IR decoders
 */

int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
{
	struct ir_raw_event_ctrl *raw;

	mutex_lock(&ir_raw_handler_lock);
	list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
	if (ir_raw_handler->raw_register)
		list_for_each_entry(raw, &ir_raw_client_list, list)
			ir_raw_handler->raw_register(raw->dev);
	available_protocols |= ir_raw_handler->protocols;
	mutex_unlock(&ir_raw_handler_lock);

	return 0;
}
EXPORT_SYMBOL(ir_raw_handler_register);

void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
{
	struct ir_raw_event_ctrl *raw;

	mutex_lock(&ir_raw_handler_lock);
	list_del(&ir_raw_handler->list);
	if (ir_raw_handler->raw_unregister)
		list_for_each_entry(raw, &ir_raw_client_list, list)
			ir_raw_handler->raw_unregister(raw->dev);
	available_protocols &= ~ir_raw_handler->protocols;
	mutex_unlock(&ir_raw_handler_lock);
}
EXPORT_SYMBOL(ir_raw_handler_unregister);

void ir_raw_init(void)
{
	/* Load the decoder modules */

	load_nec_decode();
	load_rc5_decode();
	load_rc6_decode();
	load_jvc_decode();
	load_sony_decode();
	load_sanyo_decode();
	load_sharp_decode();
	load_mce_kbd_decode();
	load_lirc_codec();
	load_xmp_decode();

	/* If needed, we may later add some init code. In this case,
	   it is needed to change the CONFIG_MODULE test at rc-core.h
	 */
}

Privacy Policy