aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/media/IR/ir-keytable.c
blob: 7961d59f5cace91b18fc6a67fef4caea09f08265 (plain) (blame)
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
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
/* ir-keytable.c - handle IR scancode->keycode tables
 *
 * Copyright (C) 2009 by Mauro Carvalho Chehab <mchehab@redhat.com>
 *
 * 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/input.h>
#include <linux/slab.h>
#include "ir-core-priv.h"

/* Sizes are in bytes, 256 bytes allows for 32 entries on x64 */
#define IR_TAB_MIN_SIZE	256
#define IR_TAB_MAX_SIZE	8192

/* FIXME: IR_KEYPRESS_TIMEOUT should be protocol specific */
#define IR_KEYPRESS_TIMEOUT 250

/**
 * ir_resize_table() - resizes a scancode table if necessary
 * @rc_tab:	the ir_scancode_table to resize
 * @return:	zero on success or a negative error code
 *
 * This routine will shrink the ir_scancode_table if it has lots of
 * unused entries and grow it if it is full.
 */
static int ir_resize_table(struct ir_scancode_table *rc_tab)
{
	unsigned int oldalloc = rc_tab->alloc;
	unsigned int newalloc = oldalloc;
	struct ir_scancode *oldscan = rc_tab->scan;
	struct ir_scancode *newscan;

	if (rc_tab->size == rc_tab->len) {
		/* All entries in use -> grow keytable */
		if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
			return -ENOMEM;

		newalloc *= 2;
		IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
	}

	if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
		/* Less than 1/3 of entries in use -> shrink keytable */
		newalloc /= 2;
		IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
	}

	if (newalloc == oldalloc)
		return 0;

	newscan = kmalloc(newalloc, GFP_ATOMIC);
	if (!newscan) {
		IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
		return -ENOMEM;
	}

	memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
	rc_tab->scan = newscan;
	rc_tab->alloc = newalloc;
	rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
	kfree(oldscan);
	return 0;
}

/**
 * ir_do_setkeycode() - internal function to set a keycode in the
 *			scancode->keycode table
 * @dev:	the struct input_dev device descriptor
 * @rc_tab:	the struct ir_scancode_table to set the keycode in
 * @scancode:	the scancode for the ir command
 * @keycode:	the keycode for the ir command
 * @resize:	whether the keytable may be shrunk
 * @return:	-EINVAL if the keycode could not be inserted, otherwise zero.
 *
 * This routine is used internally to manipulate the scancode->keycode table.
 * The caller has to hold @rc_tab->lock.
 */
static int ir_do_setkeycode(struct input_dev *dev,
			    struct ir_scancode_table *rc_tab,
			    unsigned scancode, unsigned keycode,
			    bool resize)
{
	unsigned int i;
	int old_keycode = KEY_RESERVED;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);

	/*
	 * Unfortunately, some hardware-based IR decoders don't provide
	 * all bits for the complete IR code. In general, they provide only
	 * the command part of the IR code. Yet, as it is possible to replace
	 * the provided IR with another one, it is needed to allow loading
	 * IR tables from other remotes. So,
	 */
	if (ir_dev->props && ir_dev->props->scanmask) {
		scancode &= ir_dev->props->scanmask;
	}

	/* First check if we already have a mapping for this ir command */
	for (i = 0; i < rc_tab->len; i++) {
		/* Keytable is sorted from lowest to highest scancode */
		if (rc_tab->scan[i].scancode > scancode)
			break;
		else if (rc_tab->scan[i].scancode < scancode)
			continue;

		old_keycode = rc_tab->scan[i].keycode;
		rc_tab->scan[i].keycode = keycode;

		/* Did the user wish to remove the mapping? */
		if (keycode == KEY_RESERVED || keycode == KEY_UNKNOWN) {
			IR_dprintk(1, "#%d: Deleting scan 0x%04x\n",
				   i, scancode);
			rc_tab->len--;
			memmove(&rc_tab->scan[i], &rc_tab->scan[i + 1],
				(rc_tab->len - i) * sizeof(struct ir_scancode));
		}

		/* Possibly shrink the keytable, failure is not a problem */
		ir_resize_table(rc_tab);
		break;
	}

	if (old_keycode == KEY_RESERVED && keycode != KEY_RESERVED) {
		/* No previous mapping found, we might need to grow the table */
		if (resize && ir_resize_table(rc_tab))
			return -ENOMEM;

		IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
			   i, scancode, keycode);

		/* i is the proper index to insert our new keycode */
		memmove(&rc_tab->scan[i + 1], &rc_tab->scan[i],
			(rc_tab->len - i) * sizeof(struct ir_scancode));
		rc_tab->scan[i].scancode = scancode;
		rc_tab->scan[i].keycode = keycode;
		rc_tab->len++;
		set_bit(keycode, dev->keybit);
	} else {
		IR_dprintk(1, "#%d: Replacing scan 0x%04x with key 0x%04x\n",
			   i, scancode, keycode);
		/* A previous mapping was updated... */
		clear_bit(old_keycode, dev->keybit);
		/* ...but another scancode might use the same keycode */
		for (i = 0; i < rc_tab->len; i++) {
			if (rc_tab->scan[i].keycode == old_keycode) {
				set_bit(old_keycode, dev->keybit);
				break;
			}
		}
	}

	return 0;
}

/**
 * ir_setkeycode() - set a keycode in the scancode->keycode table
 * @dev:	the struct input_dev device descriptor
 * @scancode:	the desired scancode
 * @keycode:	result
 * @return:	-EINVAL if the keycode could not be inserted, otherwise zero.
 *
 * This routine is used to handle evdev EVIOCSKEY ioctl.
 */
static int ir_setkeycode(struct input_dev *dev,
			 unsigned int scancode, unsigned int keycode)
{
	int rc;
	unsigned long flags;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

	spin_lock_irqsave(&rc_tab->lock, flags);
	rc = ir_do_setkeycode(dev, rc_tab, scancode, keycode, true);
	spin_unlock_irqrestore(&rc_tab->lock, flags);
	return rc;
}

/**
 * ir_setkeytable() - sets several entries in the scancode->keycode table
 * @dev:	the struct input_dev device descriptor
 * @to:		the struct ir_scancode_table to copy entries to
 * @from:	the struct ir_scancode_table to copy entries from
 * @return:	-EINVAL if all keycodes could not be inserted, otherwise zero.
 *
 * This routine is used to handle table initialization.
 */
static int ir_setkeytable(struct input_dev *dev,
			  struct ir_scancode_table *to,
			  const struct ir_scancode_table *from)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
	unsigned long flags;
	unsigned int i;
	int rc = 0;

	spin_lock_irqsave(&rc_tab->lock, flags);
	for (i = 0; i < from->size; i++) {
		rc = ir_do_setkeycode(dev, to, from->scan[i].scancode,
				      from->scan[i].keycode, false);
		if (rc)
			break;
	}
	spin_unlock_irqrestore(&rc_tab->lock, flags);
	return rc;
}

/**
 * ir_getkeycode() - get a keycode from the scancode->keycode table
 * @dev:	the struct input_dev device descriptor
 * @scancode:	the desired scancode
 * @keycode:	used to return the keycode, if found, or KEY_RESERVED
 * @return:	always returns zero.
 *
 * This routine is used to handle evdev EVIOCGKEY ioctl.
 */
static int ir_getkeycode(struct input_dev *dev,
			 unsigned int scancode, unsigned int *keycode)
{
	int start, end, mid;
	unsigned long flags;
	int key = KEY_RESERVED;
	struct ir_input_dev *ir_dev = input_get_drvdata(dev);
	struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;

	spin_lock_irqsave(&rc_tab->lock, flags);
	start = 0;
	end = rc_tab->len - 1;
	while (start <= end) {
		mid = (start + end) / 2;
		if (rc_tab->scan[mid].scancode < scancode)
			start = mid + 1;
		else if (rc_tab->scan[mid].scancode > scancode)
			end = mid - 1;
		else {
			key = rc_tab->scan[mid].keycode;
			break;
		}
	}
	spin_unlock_irqrestore(&rc_tab->lock, flags);

	if (key == KEY_RESERVED)
		IR_dprintk(1, "unknown key for scancode 0x%04x\n",
			   scancode);

	*keycode = key;
	return 0;
}

/**
 * ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
 * @input_dev:	the struct input_dev descriptor of the device
 * @scancode:	the scancode that we're seeking
 *
 * This routine is used by the input routines when a key is pressed at the
 * IR. The scancode is received and needs to be converted into a keycode.
 * If the key is not found, it returns KEY_RESERVED. Otherwise, returns the
 * corresponding keycode from the table.
 */
u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
{
	int keycode;

	ir_getkeycode(dev, scancode, &keycode);
	if (keycode != KEY_RESERVED)
		IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
			   dev->name, scancode, keycode);
	return keycode;
}
EXPORT_SYMBOL_GPL(ir_g_keycode_from_table);

/**
 * ir_keyup() - generates input event to cleanup a key press
 * @ir:         the struct ir_input_dev descriptor of the device
 *
 * This routine is used to signal that a key has been released on the
 * remote control. It reports a keyup input event via input_report_key().
 */
static void ir_keyup(struct ir_input_dev *ir)
{
	if (!ir->keypressed)
		return;

	IR_dprintk(1, "keyup key 0x%04x\n", ir->last_keycode);
	input_report_key(ir->input_dev, ir->last_keycode, 0);
	input_sync(ir->input_dev);
	ir->keypressed = false;
}

/**
 * ir_timer_keyup() - generates a keyup event after a timeout
 * @cookie:     a pointer to struct ir_input_dev passed to setup_timer()
 *
 * This routine will generate a keyup event some time after a keydown event
 * is generated when no further activity has been detected.
 */
static void ir_timer_keyup(unsigned long cookie)
{
	struct ir_input_dev *ir = (struct ir_input_dev *)cookie;
	unsigned long flags;

	/*
	 * ir->keyup_jiffies is used to prevent a race condition if a
	 * hardware interrupt occurs at this point and the keyup timer
	 * event is moved further into the future as a result.
	 *
	 * The timer will then be reactivated and this function called
	 * again in the future. We need to exit gracefully in that case
	 * to allow the input subsystem to do its auto-repeat magic or
	 * a keyup event might follow immediately after the keydown.
	 */
	spin_lock_irqsave(&ir->keylock, flags);
	if (time_is_before_eq_jiffies(ir->keyup_jiffies))
		ir_keyup(ir);
	spin_unlock_irqrestore(&ir->keylock, flags);
}

/**
 * ir_repeat() - notifies the IR core that a key is still pressed
 * @dev:        the struct input_dev descriptor of the device
 *
 * This routine is used by IR decoders when a repeat message which does
 * not include the necessary bits to reproduce the scancode has been
 * received.
 */
void ir_repeat(struct input_dev *dev)
{
	unsigned long flags;
	struct ir_input_dev *ir = input_get_drvdata(dev);

	spin_lock_irqsave(&ir->keylock, flags);

	input_event(dev, EV_MSC, MSC_SCAN, ir->last_scancode);

	if (!ir->keypressed)
		goto out;

	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);

out:
	spin_unlock_irqrestore(&ir->keylock, flags);
}
EXPORT_SYMBOL_GPL(ir_repeat);

/**
 * ir_keydown() - generates input event for a key press
 * @dev:        the struct input_dev descriptor of the device
 * @scancode:   the scancode that we're seeking
 * @toggle:     the toggle value (protocol dependent, if the protocol doesn't
 *              support toggle values, this should be set to zero)
 *
 * This routine is used by the input routines when a key is pressed at the
 * IR. It gets the keycode for a scancode and reports an input event via
 * input_report_key().
 */
void ir_keydown(struct input_dev *dev, int scancode, u8 toggle)
{
	unsigned long flags;
	struct ir_input_dev *ir = input_get_drvdata(dev);

	u32 keycode = ir_g_keycode_from_table(dev, scancode);

	spin_lock_irqsave(&ir->keylock, flags);

	input_event(dev, EV_MSC, MSC_SCAN, scancode);

	/* Repeat event? */
	if (ir->keypressed &&
	    ir->last_scancode == scancode &&
	    ir->last_toggle == toggle)
		goto set_timer;

	/* Release old keypress */
	ir_keyup(ir);

	ir->last_scancode = scancode;
	ir->last_toggle = toggle;
	ir->last_keycode = keycode;


	if (keycode == KEY_RESERVED)
		goto out;


	/* Register a keypress */
	ir->keypressed = true;
	IR_dprintk(1, "%s: key down event, key 0x%04x, scancode 0x%04x\n",
		   dev->name, keycode, scancode);
	input_report_key(dev, ir->last_keycode, 1);
	input_sync(dev);

set_timer:
	ir->keyup_jiffies = jiffies + msecs_to_jiffies(IR_KEYPRESS_TIMEOUT);
	mod_timer(&ir->timer_keyup, ir->keyup_jiffies);
out:
	spin_unlock_irqrestore(&ir->keylock, flags);
}
EXPORT_SYMBOL_GPL(ir_keydown);

static int ir_open(struct input_dev *input_dev)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);

	return ir_dev->props->open(ir_dev->props->priv);
}

static void ir_close(struct input_dev *input_dev)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);

	ir_dev->props->close(ir_dev->props->priv);
}

/**
 * __ir_input_register() - sets the IR keycode table and add the handlers
 *			    for keymap table get/set
 * @input_dev:	the struct input_dev descriptor of the device
 * @rc_tab:	the struct ir_scancode_table table of scancode/keymap
 *
 * This routine is used to initialize the input infrastructure
 * to work with an IR.
 * It will register the input/evdev interface for the device and
 * register the syfs code for IR class
 */
int __ir_input_register(struct input_dev *input_dev,
		      const struct ir_scancode_table *rc_tab,
		      struct ir_dev_props *props,
		      const char *driver_name)
{
	struct ir_input_dev *ir_dev;
	int rc;

	if (rc_tab->scan == NULL || !rc_tab->size)
		return -EINVAL;

	ir_dev = kzalloc(sizeof(*ir_dev), GFP_KERNEL);
	if (!ir_dev)
		return -ENOMEM;

	ir_dev->driver_name = kasprintf(GFP_KERNEL, "%s", driver_name);
	if (!ir_dev->driver_name) {
		rc = -ENOMEM;
		goto out_dev;
	}

	input_dev->getkeycode = ir_getkeycode;
	input_dev->setkeycode = ir_setkeycode;
	input_set_drvdata(input_dev, ir_dev);
	ir_dev->input_dev = input_dev;

	spin_lock_init(&ir_dev->rc_tab.lock);
	spin_lock_init(&ir_dev->keylock);
	setup_timer(&ir_dev->timer_keyup, ir_timer_keyup, (unsigned long)ir_dev);

	ir_dev->rc_tab.name = rc_tab->name;
	ir_dev->rc_tab.ir_type = rc_tab->ir_type;
	ir_dev->rc_tab.alloc = roundup_pow_of_two(rc_tab->size *
						  sizeof(struct ir_scancode));
	ir_dev->rc_tab.scan = kmalloc(ir_dev->rc_tab.alloc, GFP_KERNEL);
	ir_dev->rc_tab.size = ir_dev->rc_tab.alloc / sizeof(struct ir_scancode);
	if (props) {
		ir_dev->props = props;
		if (props->open)
			input_dev->open = ir_open;
		if (props->close)
			input_dev->close = ir_close;
	}

	if (!ir_dev->rc_tab.scan) {
		rc = -ENOMEM;
		goto out_name;
	}

	IR_dprintk(1, "Allocated space for %u keycode entries (%u bytes)\n",
		   ir_dev->rc_tab.size, ir_dev->rc_tab.alloc);

	set_bit(EV_KEY, input_dev->evbit);
	set_bit(EV_REP, input_dev->evbit);
	set_bit(EV_MSC, input_dev->evbit);
	set_bit(MSC_SCAN, input_dev->mscbit);

	if (ir_setkeytable(input_dev, &ir_dev->rc_tab, rc_tab)) {
		rc = -ENOMEM;
		goto out_table;
	}

	rc = ir_register_class(input_dev);
	if (rc < 0)
		goto out_table;

	if (ir_dev->props)
		if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW) {
			rc = ir_raw_event_register(input_dev);
			if (rc < 0)
				goto out_event;
		}

	IR_dprintk(1, "Registered input device on %s for %s remote%s.\n",
		   driver_name, rc_tab->name,
		   (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_IR_RAW) ?
			" in raw mode" : "");

	/*
	 * Default delay of 250ms is too short for some protocols, expecially
	 * since the timeout is currently set to 250ms. Increase it to 500ms,
	 * to avoid wrong repetition of the keycodes.
	 */
	input_dev->rep[REP_DELAY] = 500;

	return 0;

out_event:
	ir_unregister_class(input_dev);
out_table:
	kfree(ir_dev->rc_tab.scan);
out_name:
	kfree(ir_dev->driver_name);
out_dev:
	kfree(ir_dev);
	return rc;
}
EXPORT_SYMBOL_GPL(__ir_input_register);

/**
 * ir_input_unregister() - unregisters IR and frees resources
 * @input_dev:	the struct input_dev descriptor of the device

 * This routine is used to free memory and de-register interfaces.
 */
void ir_input_unregister(struct input_dev *input_dev)
{
	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
	struct ir_scancode_table *rc_tab;

	if (!ir_dev)
		return;

	IR_dprintk(1, "Freed keycode table\n");

	del_timer_sync(&ir_dev->timer_keyup);
	if (ir_dev->props)
		if (ir_dev->props->driver_type == RC_DRIVER_IR_RAW)
			ir_raw_event_unregister(input_dev);

	rc_tab = &ir_dev->rc_tab;
	rc_tab->size = 0;
	kfree(rc_tab->scan);
	rc_tab->scan = NULL;

	ir_unregister_class(input_dev);

	kfree(ir_dev->driver_name);
	kfree(ir_dev);
}
EXPORT_SYMBOL_GPL(ir_input_unregister);

int ir_core_debug;    /* ir_debug level (0,1,2) */
EXPORT_SYMBOL_GPL(ir_core_debug);
module_param_named(debug, ir_core_debug, int, 0644);

MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
MODULE_LICENSE("GPL");