summaryrefslogtreecommitdiff
path: root/drivers/media/rc/ir-mce_kbd-decoder.c
blob: 67f1c179c713dcede5b5a5809107e2a92199905c (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
/* ir-mce_kbd-decoder.c - A decoder for the RC6-ish keyboard/mouse IR protocol
 * used by the Microsoft Remote Keyboard for Windows Media Center Edition,
 * referred to by Microsoft's Windows Media Center remote specification docs
 * as "an internal protocol called MCIR-2".
 *
 * Copyright (C) 2011 by Jarod Wilson <jarod@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/module.h>

#include "rc-core-priv.h"

/*
 * This decoder currently supports:
 * - MCIR-2 29-bit IR signals used for mouse movement and buttons
 * - MCIR-2 32-bit IR signals used for standard keyboard keys
 *
 * The media keys on the keyboard send RC-6 signals that are indistinguishable
 * from the keys of the same name on the stock MCE remote, and will be handled
 * by the standard RC-6 decoder, and be made available to the system via the
 * input device for the remote, rather than the keyboard/mouse one.
 */

#define MCIR2_UNIT		333333	/* ns */
#define MCIR2_HEADER_NBITS	5
#define MCIR2_MOUSE_NBITS	29
#define MCIR2_KEYBOARD_NBITS	32
#define MCIR2_PREFIX_PULSE	(8 * MCIR2_UNIT)
#define MCIR2_PREFIX_SPACE	(1 * MCIR2_UNIT)
#define MCIR2_MAX_LEN		(3 * MCIR2_UNIT)
#define MCIR2_BIT_START		(1 * MCIR2_UNIT)
#define MCIR2_BIT_END		(1 * MCIR2_UNIT)
#define MCIR2_BIT_0		(1 * MCIR2_UNIT)
#define MCIR2_BIT_SET		(2 * MCIR2_UNIT)
#define MCIR2_MODE_MASK		0xf	/* for the header bits */
#define MCIR2_KEYBOARD_HEADER	0x4
#define MCIR2_MOUSE_HEADER	0x1
#define MCIR2_MASK_KEYS_START	0xe0

enum mce_kbd_mode {
	MCIR2_MODE_KEYBOARD,
	MCIR2_MODE_MOUSE,
	MCIR2_MODE_UNKNOWN,
};

enum mce_kbd_state {
	STATE_INACTIVE,
	STATE_HEADER_BIT_START,
	STATE_HEADER_BIT_END,
	STATE_BODY_BIT_START,
	STATE_BODY_BIT_END,
	STATE_FINISHED,
};

static unsigned char kbd_keycodes[256] = {
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_A,
	KEY_B,		KEY_C,		KEY_D,		KEY_E,		KEY_F,
	KEY_G,		KEY_H,		KEY_I,		KEY_J,		KEY_K,
	KEY_L,		KEY_M,		KEY_N,		KEY_O,		KEY_P,
	KEY_Q,		KEY_R,		KEY_S,		KEY_T,		KEY_U,
	KEY_V,		KEY_W,		KEY_X,		KEY_Y,		KEY_Z,
	KEY_1,		KEY_2,		KEY_3,		KEY_4,		KEY_5,
	KEY_6,		KEY_7,		KEY_8,		KEY_9,		KEY_0,
	KEY_ENTER,	KEY_ESC,	KEY_BACKSPACE,	KEY_TAB,	KEY_SPACE,
	KEY_MINUS,	KEY_EQUAL,	KEY_LEFTBRACE,	KEY_RIGHTBRACE,	KEY_BACKSLASH,
	KEY_BACKSLASH,	KEY_SEMICOLON,	KEY_APOSTROPHE,	KEY_GRAVE,	KEY_COMMA,
	KEY_DOT,	KEY_SLASH,	KEY_CAPSLOCK,	KEY_F1,		KEY_F2,
	KEY_F3,		KEY_F4,		KEY_F5,		KEY_F6,		KEY_F7,
	KEY_F8,		KEY_F9,		KEY_F10,	KEY_F11,	KEY_F12,
	KEY_SYSRQ,	KEY_SCROLLLOCK,	KEY_PAUSE,	KEY_INSERT,	KEY_HOME,
	KEY_PAGEUP,	KEY_DELETE,	KEY_END,	KEY_PAGEDOWN,	KEY_RIGHT,
	KEY_LEFT,	KEY_DOWN,	KEY_UP,		KEY_NUMLOCK,	KEY_KPSLASH,
	KEY_KPASTERISK,	KEY_KPMINUS,	KEY_KPPLUS,	KEY_KPENTER,	KEY_KP1,
	KEY_KP2,	KEY_KP3,	KEY_KP4,	KEY_KP5,	KEY_KP6,
	KEY_KP7,	KEY_KP8,	KEY_KP9,	KEY_KP0,	KEY_KPDOT,
	KEY_102ND,	KEY_COMPOSE,	KEY_POWER,	KEY_KPEQUAL,	KEY_F13,
	KEY_F14,	KEY_F15,	KEY_F16,	KEY_F17,	KEY_F18,
	KEY_F19,	KEY_F20,	KEY_F21,	KEY_F22,	KEY_F23,
	KEY_F24,	KEY_OPEN,	KEY_HELP,	KEY_PROPS,	KEY_FRONT,
	KEY_STOP,	KEY_AGAIN,	KEY_UNDO,	KEY_CUT,	KEY_COPY,
	KEY_PASTE,	KEY_FIND,	KEY_MUTE,	KEY_VOLUMEUP,	KEY_VOLUMEDOWN,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_KPCOMMA,	KEY_RESERVED,
	KEY_RO,		KEY_KATAKANAHIRAGANA, KEY_YEN,	KEY_HENKAN,	KEY_MUHENKAN,
	KEY_KPJPCOMMA,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_HANGUEL,
	KEY_HANJA,	KEY_KATAKANA,	KEY_HIRAGANA,	KEY_ZENKAKUHANKAKU, KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,	KEY_LEFTCTRL,
	KEY_LEFTSHIFT,	KEY_LEFTALT,	KEY_LEFTMETA,	KEY_RIGHTCTRL,	KEY_RIGHTSHIFT,
	KEY_RIGHTALT,	KEY_RIGHTMETA,	KEY_PLAYPAUSE,	KEY_STOPCD,	KEY_PREVIOUSSONG,
	KEY_NEXTSONG,	KEY_EJECTCD,	KEY_VOLUMEUP,	KEY_VOLUMEDOWN,	KEY_MUTE,
	KEY_WWW,	KEY_BACK,	KEY_FORWARD,	KEY_STOP,	KEY_FIND,
	KEY_SCROLLUP,	KEY_SCROLLDOWN,	KEY_EDIT,	KEY_SLEEP,	KEY_COFFEE,
	KEY_REFRESH,	KEY_CALC,	KEY_RESERVED,	KEY_RESERVED,	KEY_RESERVED,
	KEY_RESERVED
};

static void mce_kbd_rx_timeout(struct timer_list *t)
{
	struct ir_raw_event_ctrl *raw = from_timer(raw, t, mce_kbd.rx_timeout);
	unsigned char maskcode;
	unsigned long flags;
	int i;

	dev_dbg(&raw->dev->dev, "timer callback clearing all keys\n");

	spin_lock_irqsave(&raw->mce_kbd.keylock, flags);

	if (time_is_before_eq_jiffies(raw->mce_kbd.rx_timeout.expires)) {
		for (i = 0; i < 7; i++) {
			maskcode = kbd_keycodes[MCIR2_MASK_KEYS_START + i];
			input_report_key(raw->dev->input_dev, maskcode, 0);
		}

		for (i = 0; i < MCIR2_MASK_KEYS_START; i++)
			input_report_key(raw->dev->input_dev, kbd_keycodes[i],
					 0);

		input_sync(raw->dev->input_dev);
	}
	spin_unlock_irqrestore(&raw->mce_kbd.keylock, flags);
}

static enum mce_kbd_mode mce_kbd_mode(struct mce_kbd_dec *data)
{
	switch (data->header & MCIR2_MODE_MASK) {
	case MCIR2_KEYBOARD_HEADER:
		return MCIR2_MODE_KEYBOARD;
	case MCIR2_MOUSE_HEADER:
		return MCIR2_MODE_MOUSE;
	default:
		return MCIR2_MODE_UNKNOWN;
	}
}

static void ir_mce_kbd_process_keyboard_data(struct rc_dev *dev, u32 scancode)
{
	u8 keydata1  = (scancode >> 8) & 0xff;
	u8 keydata2  = (scancode >> 16) & 0xff;
	u8 shiftmask = scancode & 0xff;
	unsigned char maskcode;
	int i, keystate;

	dev_dbg(&dev->dev, "keyboard: keydata2 = 0x%02x, keydata1 = 0x%02x, shiftmask = 0x%02x\n",
		keydata2, keydata1, shiftmask);

	for (i = 0; i < 7; i++) {
		maskcode = kbd_keycodes[MCIR2_MASK_KEYS_START + i];
		if (shiftmask & (1 << i))
			keystate = 1;
		else
			keystate = 0;
		input_report_key(dev->input_dev, maskcode, keystate);
	}

	if (keydata1)
		input_report_key(dev->input_dev, kbd_keycodes[keydata1], 1);
	if (keydata2)
		input_report_key(dev->input_dev, kbd_keycodes[keydata2], 1);

	if (!keydata1 && !keydata2) {
		for (i = 0; i < MCIR2_MASK_KEYS_START; i++)
			input_report_key(dev->input_dev, kbd_keycodes[i], 0);
	}
}

static void ir_mce_kbd_process_mouse_data(struct rc_dev *dev, u32 scancode)
{
	/* raw mouse coordinates */
	u8 xdata = (scancode >> 7) & 0x7f;
	u8 ydata = (scancode >> 14) & 0x7f;
	int x, y;
	/* mouse buttons */
	bool right = scancode & 0x40;
	bool left  = scancode & 0x20;

	if (xdata & 0x40)
		x = -((~xdata & 0x7f) + 1);
	else
		x = xdata;

	if (ydata & 0x40)
		y = -((~ydata & 0x7f) + 1);
	else
		y = ydata;

	dev_dbg(&dev->dev, "mouse: x = %d, y = %d, btns = %s%s\n",
		x, y, left ? "L" : "", right ? "R" : "");

	input_report_rel(dev->input_dev, REL_X, x);
	input_report_rel(dev->input_dev, REL_Y, y);

	input_report_key(dev->input_dev, BTN_LEFT, left);
	input_report_key(dev->input_dev, BTN_RIGHT, right);
}

/**
 * ir_mce_kbd_decode() - Decode one mce_kbd pulse or space
 * @dev:	the struct rc_dev descriptor of the device
 * @ev:		the struct ir_raw_event descriptor of the pulse/space
 *
 * This function returns -EINVAL if the pulse violates the state machine
 */
static int ir_mce_kbd_decode(struct rc_dev *dev, struct ir_raw_event ev)
{
	struct mce_kbd_dec *data = &dev->raw->mce_kbd;
	u32 scancode;
	unsigned long delay;
	struct lirc_scancode lsc = {};

	if (!is_timing_event(ev)) {
		if (ev.reset)
			data->state = STATE_INACTIVE;
		return 0;
	}

	if (!geq_margin(ev.duration, MCIR2_UNIT, MCIR2_UNIT / 2))
		goto out;

again:
	dev_dbg(&dev->dev, "started at state %i (%uus %s)\n",
		data->state, TO_US(ev.duration), TO_STR(ev.pulse));

	if (!geq_margin(ev.duration, MCIR2_UNIT, MCIR2_UNIT / 2))
		return 0;

	switch (data->state) {

	case STATE_INACTIVE:
		if (!ev.pulse)
			break;

		/* Note: larger margin on first pulse since each MCIR2_UNIT
		   is quite short and some hardware takes some time to
		   adjust to the signal */
		if (!eq_margin(ev.duration, MCIR2_PREFIX_PULSE, MCIR2_UNIT))
			break;

		data->state = STATE_HEADER_BIT_START;
		data->count = 0;
		data->header = 0;
		return 0;

	case STATE_HEADER_BIT_START:
		if (geq_margin(ev.duration, MCIR2_MAX_LEN, MCIR2_UNIT / 2))
			break;

		data->header <<= 1;
		if (ev.pulse)
			data->header |= 1;
		data->count++;
		data->state = STATE_HEADER_BIT_END;
		return 0;

	case STATE_HEADER_BIT_END:
		decrease_duration(&ev, MCIR2_BIT_END);

		if (data->count != MCIR2_HEADER_NBITS) {
			data->state = STATE_HEADER_BIT_START;
			goto again;
		}

		switch (mce_kbd_mode(data)) {
		case MCIR2_MODE_KEYBOARD:
			data->wanted_bits = MCIR2_KEYBOARD_NBITS;
			break;
		case MCIR2_MODE_MOUSE:
			data->wanted_bits = MCIR2_MOUSE_NBITS;
			break;
		default:
			dev_dbg(&dev->dev, "not keyboard or mouse data\n");
			goto out;
		}

		data->count = 0;
		data->body = 0;
		data->state = STATE_BODY_BIT_START;
		goto again;

	case STATE_BODY_BIT_START:
		if (geq_margin(ev.duration, MCIR2_MAX_LEN, MCIR2_UNIT / 2))
			break;

		data->body <<= 1;
		if (ev.pulse)
			data->body |= 1;
		data->count++;
		data->state = STATE_BODY_BIT_END;
		return 0;

	case STATE_BODY_BIT_END:
		if (data->count == data->wanted_bits)
			data->state = STATE_FINISHED;
		else
			data->state = STATE_BODY_BIT_START;

		decrease_duration(&ev, MCIR2_BIT_END);
		goto again;

	case STATE_FINISHED:
		if (ev.pulse)
			break;

		switch (data->wanted_bits) {
		case MCIR2_KEYBOARD_NBITS:
			scancode = data->body & 0xffffff;
			dev_dbg(&dev->dev, "keyboard data 0x%08x\n",
				data->body);
			spin_lock(&data->keylock);
			if (scancode) {
				delay = nsecs_to_jiffies(dev->timeout) +
					msecs_to_jiffies(100);
				mod_timer(&data->rx_timeout, jiffies + delay);
			} else {
				del_timer(&data->rx_timeout);
			}
			/* Pass data to keyboard buffer parser */
			ir_mce_kbd_process_keyboard_data(dev, scancode);
			spin_unlock(&data->keylock);
			lsc.rc_proto = RC_PROTO_MCIR2_KBD;
			break;
		case MCIR2_MOUSE_NBITS:
			scancode = data->body & 0x1fffff;
			dev_dbg(&dev->dev, "mouse data 0x%06x\n", scancode);
			/* Pass data to mouse buffer parser */
			ir_mce_kbd_process_mouse_data(dev, scancode);
			lsc.rc_proto = RC_PROTO_MCIR2_MSE;
			break;
		default:
			dev_dbg(&dev->dev, "not keyboard or mouse data\n");
			goto out;
		}

		lsc.scancode = scancode;
		ir_lirc_scancode_event(dev, &lsc);
		data->state = STATE_INACTIVE;
		input_event(dev->input_dev, EV_MSC, MSC_SCAN, scancode);
		input_sync(dev->input_dev);
		return 0;
	}

out:
	dev_dbg(&dev->dev, "failed at state %i (%uus %s)\n",
		data->state, TO_US(ev.duration), TO_STR(ev.pulse));
	data->state = STATE_INACTIVE;
	return -EINVAL;
}

static int ir_mce_kbd_register(struct rc_dev *dev)
{
	struct mce_kbd_dec *mce_kbd = &dev->raw->mce_kbd;

	timer_setup(&mce_kbd->rx_timeout, mce_kbd_rx_timeout, 0);
	spin_lock_init(&mce_kbd->keylock);

	return 0;
}

static int ir_mce_kbd_unregister(struct rc_dev *dev)
{
	struct mce_kbd_dec *mce_kbd = &dev->raw->mce_kbd;

	del_timer_sync(&mce_kbd->rx_timeout);

	return 0;
}

static const struct ir_raw_timings_manchester ir_mce_kbd_timings = {
	.leader_pulse	= MCIR2_PREFIX_PULSE,
	.invert		= 1,
	.clock		= MCIR2_UNIT,
	.trailer_space	= MCIR2_UNIT * 10,
};

/**
 * ir_mce_kbd_encode() - Encode a scancode as a stream of raw events
 *
 * @protocol:   protocol to encode
 * @scancode:   scancode to encode
 * @events:     array of raw ir events to write into
 * @max:        maximum size of @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.
 */
static int ir_mce_kbd_encode(enum rc_proto protocol, u32 scancode,
			     struct ir_raw_event *events, unsigned int max)
{
	struct ir_raw_event *e = events;
	int len, ret;
	u64 raw;

	if (protocol == RC_PROTO_MCIR2_KBD) {
		raw = scancode |
		      ((u64)MCIR2_KEYBOARD_HEADER << MCIR2_KEYBOARD_NBITS);
		len = MCIR2_KEYBOARD_NBITS + MCIR2_HEADER_NBITS;
	} else {
		raw = scancode |
		      ((u64)MCIR2_MOUSE_HEADER << MCIR2_MOUSE_NBITS);
		len = MCIR2_MOUSE_NBITS + MCIR2_HEADER_NBITS;
	}

	ret = ir_raw_gen_manchester(&e, max, &ir_mce_kbd_timings, len, raw);
	if (ret < 0)
		return ret;

	return e - events;
}

static struct ir_raw_handler mce_kbd_handler = {
	.protocols	= RC_PROTO_BIT_MCIR2_KBD | RC_PROTO_BIT_MCIR2_MSE,
	.decode		= ir_mce_kbd_decode,
	.encode		= ir_mce_kbd_encode,
	.raw_register	= ir_mce_kbd_register,
	.raw_unregister	= ir_mce_kbd_unregister,
	.carrier	= 36000,
	.min_timeout	= MCIR2_MAX_LEN + MCIR2_UNIT / 2,
};

static int __init ir_mce_kbd_decode_init(void)
{
	ir_raw_handler_register(&mce_kbd_handler);

	printk(KERN_INFO "IR MCE Keyboard/mouse protocol handler initialized\n");
	return 0;
}

static void __exit ir_mce_kbd_decode_exit(void)
{
	ir_raw_handler_unregister(&mce_kbd_handler);
}

module_init(ir_mce_kbd_decode_init);
module_exit(ir_mce_kbd_decode_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jarod Wilson <jarod@redhat.com>");
MODULE_DESCRIPTION("MCE Keyboard/mouse IR protocol decoder");