1 /* ir-mce_kbd-decoder.c - A decoder for the RC6-ish keyboard/mouse IR protocol
2 * used by the Microsoft Remote Keyboard for Windows Media Center Edition,
3 * referred to by Microsoft's Windows Media Center remote specification docs
4 * as "an internal protocol called MCIR-2".
5 *
6 * Copyright (C) 2011 by Jarod Wilson <jarod@redhat.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation version 2 of the License.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 */
17 #include <linux/module.h>
18
19 #include "rc-core-priv.h"
20
21 /*
22 * This decoder currently supports:
23 * - MCIR-2 29-bit IR signals used for mouse movement and buttons
24 * - MCIR-2 32-bit IR signals used for standard keyboard keys
25 *
26 * The media keys on the keyboard send RC-6 signals that are inditinguishable
27 * from the keys of the same name on the stock MCE remote, and will be handled
28 * by the standard RC-6 decoder, and be made available to the system via the
29 * input device for the remote, rather than the keyboard/mouse one.
30 */
31
32 #define MCIR2_UNIT 333333 /* ns */
33 #define MCIR2_HEADER_NBITS 5
34 #define MCIR2_MOUSE_NBITS 29
35 #define MCIR2_KEYBOARD_NBITS 32
36 #define MCIR2_PREFIX_PULSE (8 * MCIR2_UNIT)
37 #define MCIR2_PREFIX_SPACE (1 * MCIR2_UNIT)
38 #define MCIR2_MAX_LEN (3 * MCIR2_UNIT)
39 #define MCIR2_BIT_START (1 * MCIR2_UNIT)
40 #define MCIR2_BIT_END (1 * MCIR2_UNIT)
41 #define MCIR2_BIT_0 (1 * MCIR2_UNIT)
42 #define MCIR2_BIT_SET (2 * MCIR2_UNIT)
43 #define MCIR2_MODE_MASK 0xf /* for the header bits */
44 #define MCIR2_KEYBOARD_HEADER 0x4
45 #define MCIR2_MOUSE_HEADER 0x1
46 #define MCIR2_MASK_KEYS_START 0xe0
47
48 enum mce_kbd_mode {
49 MCIR2_MODE_KEYBOARD,
50 MCIR2_MODE_MOUSE,
51 MCIR2_MODE_UNKNOWN,
52 };
53
54 enum mce_kbd_state {
55 STATE_INACTIVE,
56 STATE_HEADER_BIT_START,
57 STATE_HEADER_BIT_END,
58 STATE_BODY_BIT_START,
59 STATE_BODY_BIT_END,
60 STATE_FINISHED,
61 };
62
63 static unsigned char kbd_keycodes[256] = {
64 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_A,
65 KEY_B, KEY_C, KEY_D, KEY_E, KEY_F,
66 KEY_G, KEY_H, KEY_I, KEY_J, KEY_K,
67 KEY_L, KEY_M, KEY_N, KEY_O, KEY_P,
68 KEY_Q, KEY_R, KEY_S, KEY_T, KEY_U,
69 KEY_V, KEY_W, KEY_X, KEY_Y, KEY_Z,
70 KEY_1, KEY_2, KEY_3, KEY_4, KEY_5,
71 KEY_6, KEY_7, KEY_8, KEY_9, KEY_0,
72 KEY_ENTER, KEY_ESC, KEY_BACKSPACE, KEY_TAB, KEY_SPACE,
73 KEY_MINUS, KEY_EQUAL, KEY_LEFTBRACE, KEY_RIGHTBRACE, KEY_BACKSLASH,
74 KEY_RESERVED, KEY_SEMICOLON, KEY_APOSTROPHE, KEY_GRAVE, KEY_COMMA,
75 KEY_DOT, KEY_SLASH, KEY_CAPSLOCK, KEY_F1, KEY_F2,
76 KEY_F3, KEY_F4, KEY_F5, KEY_F6, KEY_F7,
77 KEY_F8, KEY_F9, KEY_F10, KEY_F11, KEY_F12,
78 KEY_SYSRQ, KEY_SCROLLLOCK, KEY_PAUSE, KEY_INSERT, KEY_HOME,
79 KEY_PAGEUP, KEY_DELETE, KEY_END, KEY_PAGEDOWN, KEY_RIGHT,
80 KEY_LEFT, KEY_DOWN, KEY_UP, KEY_NUMLOCK, KEY_KPSLASH,
81 KEY_KPASTERISK, KEY_KPMINUS, KEY_KPPLUS, KEY_KPENTER, KEY_KP1,
82 KEY_KP2, KEY_KP3, KEY_KP4, KEY_KP5, KEY_KP6,
83 KEY_KP7, KEY_KP8, KEY_KP9, KEY_KP0, KEY_KPDOT,
84 KEY_102ND, KEY_COMPOSE, KEY_POWER, KEY_KPEQUAL, KEY_F13,
85 KEY_F14, KEY_F15, KEY_F16, KEY_F17, KEY_F18,
86 KEY_F19, KEY_F20, KEY_F21, KEY_F22, KEY_F23,
87 KEY_F24, KEY_OPEN, KEY_HELP, KEY_PROPS, KEY_FRONT,
88 KEY_STOP, KEY_AGAIN, KEY_UNDO, KEY_CUT, KEY_COPY,
89 KEY_PASTE, KEY_FIND, KEY_MUTE, KEY_VOLUMEUP, KEY_VOLUMEDOWN,
90 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_KPCOMMA, KEY_RESERVED,
91 KEY_RO, KEY_KATAKANAHIRAGANA, KEY_YEN, KEY_HENKAN, KEY_MUHENKAN,
92 KEY_KPJPCOMMA, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_HANGUEL,
93 KEY_HANJA, KEY_KATAKANA, KEY_HIRAGANA, KEY_ZENKAKUHANKAKU, KEY_RESERVED,
94 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
95 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
96 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
97 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
98 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
99 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
100 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
101 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
102 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
103 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
104 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
105 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
106 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
107 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
108 KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED, KEY_LEFTCTRL,
109 KEY_LEFTSHIFT, KEY_LEFTALT, KEY_LEFTMETA, KEY_RIGHTCTRL, KEY_RIGHTSHIFT,
110 KEY_RIGHTALT, KEY_RIGHTMETA, KEY_PLAYPAUSE, KEY_STOPCD, KEY_PREVIOUSSONG,
111 KEY_NEXTSONG, KEY_EJECTCD, KEY_VOLUMEUP, KEY_VOLUMEDOWN, KEY_MUTE,
112 KEY_WWW, KEY_BACK, KEY_FORWARD, KEY_STOP, KEY_FIND,
113 KEY_SCROLLUP, KEY_SCROLLDOWN, KEY_EDIT, KEY_SLEEP, KEY_COFFEE,
114 KEY_REFRESH, KEY_CALC, KEY_RESERVED, KEY_RESERVED, KEY_RESERVED,
115 KEY_RESERVED
116 };
117
mce_kbd_rx_timeout(unsigned long data)118 static void mce_kbd_rx_timeout(unsigned long data)
119 {
120 struct mce_kbd_dec *mce_kbd = (struct mce_kbd_dec *)data;
121 int i;
122 unsigned char maskcode;
123
124 IR_dprintk(2, "timer callback clearing all keys\n");
125
126 for (i = 0; i < 7; i++) {
127 maskcode = kbd_keycodes[MCIR2_MASK_KEYS_START + i];
128 input_report_key(mce_kbd->idev, maskcode, 0);
129 }
130
131 for (i = 0; i < MCIR2_MASK_KEYS_START; i++)
132 input_report_key(mce_kbd->idev, kbd_keycodes[i], 0);
133 }
134
mce_kbd_mode(struct mce_kbd_dec * data)135 static enum mce_kbd_mode mce_kbd_mode(struct mce_kbd_dec *data)
136 {
137 switch (data->header & MCIR2_MODE_MASK) {
138 case MCIR2_KEYBOARD_HEADER:
139 return MCIR2_MODE_KEYBOARD;
140 case MCIR2_MOUSE_HEADER:
141 return MCIR2_MODE_MOUSE;
142 default:
143 return MCIR2_MODE_UNKNOWN;
144 }
145 }
146
ir_mce_kbd_process_keyboard_data(struct input_dev * idev,u32 scancode)147 static void ir_mce_kbd_process_keyboard_data(struct input_dev *idev,
148 u32 scancode)
149 {
150 u8 keydata = (scancode >> 8) & 0xff;
151 u8 shiftmask = scancode & 0xff;
152 unsigned char keycode, maskcode;
153 int i, keystate;
154
155 IR_dprintk(1, "keyboard: keydata = 0x%02x, shiftmask = 0x%02x\n",
156 keydata, shiftmask);
157
158 for (i = 0; i < 7; i++) {
159 maskcode = kbd_keycodes[MCIR2_MASK_KEYS_START + i];
160 if (shiftmask & (1 << i))
161 keystate = 1;
162 else
163 keystate = 0;
164 input_report_key(idev, maskcode, keystate);
165 }
166
167 if (keydata) {
168 keycode = kbd_keycodes[keydata];
169 input_report_key(idev, keycode, 1);
170 } else {
171 for (i = 0; i < MCIR2_MASK_KEYS_START; i++)
172 input_report_key(idev, kbd_keycodes[i], 0);
173 }
174 }
175
ir_mce_kbd_process_mouse_data(struct input_dev * idev,u32 scancode)176 static void ir_mce_kbd_process_mouse_data(struct input_dev *idev, u32 scancode)
177 {
178 /* raw mouse coordinates */
179 u8 xdata = (scancode >> 7) & 0x7f;
180 u8 ydata = (scancode >> 14) & 0x7f;
181 int x, y;
182 /* mouse buttons */
183 bool right = scancode & 0x40;
184 bool left = scancode & 0x20;
185
186 if (xdata & 0x40)
187 x = -((~xdata & 0x7f) + 1);
188 else
189 x = xdata;
190
191 if (ydata & 0x40)
192 y = -((~ydata & 0x7f) + 1);
193 else
194 y = ydata;
195
196 IR_dprintk(1, "mouse: x = %d, y = %d, btns = %s%s\n",
197 x, y, left ? "L" : "", right ? "R" : "");
198
199 input_report_rel(idev, REL_X, x);
200 input_report_rel(idev, REL_Y, y);
201
202 input_report_key(idev, BTN_LEFT, left);
203 input_report_key(idev, BTN_RIGHT, right);
204 }
205
206 /**
207 * ir_mce_kbd_decode() - Decode one mce_kbd pulse or space
208 * @dev: the struct rc_dev descriptor of the device
209 * @ev: the struct ir_raw_event descriptor of the pulse/space
210 *
211 * This function returns -EINVAL if the pulse violates the state machine
212 */
ir_mce_kbd_decode(struct rc_dev * dev,struct ir_raw_event ev)213 static int ir_mce_kbd_decode(struct rc_dev *dev, struct ir_raw_event ev)
214 {
215 struct mce_kbd_dec *data = &dev->raw->mce_kbd;
216 u32 scancode;
217 unsigned long delay;
218
219 if (!(dev->enabled_protocols & RC_BIT_MCE_KBD))
220 return 0;
221
222 if (!is_timing_event(ev)) {
223 if (ev.reset)
224 data->state = STATE_INACTIVE;
225 return 0;
226 }
227
228 if (!geq_margin(ev.duration, MCIR2_UNIT, MCIR2_UNIT / 2))
229 goto out;
230
231 again:
232 IR_dprintk(2, "started at state %i (%uus %s)\n",
233 data->state, TO_US(ev.duration), TO_STR(ev.pulse));
234
235 if (!geq_margin(ev.duration, MCIR2_UNIT, MCIR2_UNIT / 2))
236 return 0;
237
238 switch (data->state) {
239
240 case STATE_INACTIVE:
241 if (!ev.pulse)
242 break;
243
244 /* Note: larger margin on first pulse since each MCIR2_UNIT
245 is quite short and some hardware takes some time to
246 adjust to the signal */
247 if (!eq_margin(ev.duration, MCIR2_PREFIX_PULSE, MCIR2_UNIT))
248 break;
249
250 data->state = STATE_HEADER_BIT_START;
251 data->count = 0;
252 data->header = 0;
253 return 0;
254
255 case STATE_HEADER_BIT_START:
256 if (geq_margin(ev.duration, MCIR2_MAX_LEN, MCIR2_UNIT / 2))
257 break;
258
259 data->header <<= 1;
260 if (ev.pulse)
261 data->header |= 1;
262 data->count++;
263 data->state = STATE_HEADER_BIT_END;
264 return 0;
265
266 case STATE_HEADER_BIT_END:
267 if (!is_transition(&ev, &dev->raw->prev_ev))
268 break;
269
270 decrease_duration(&ev, MCIR2_BIT_END);
271
272 if (data->count != MCIR2_HEADER_NBITS) {
273 data->state = STATE_HEADER_BIT_START;
274 goto again;
275 }
276
277 switch (mce_kbd_mode(data)) {
278 case MCIR2_MODE_KEYBOARD:
279 data->wanted_bits = MCIR2_KEYBOARD_NBITS;
280 break;
281 case MCIR2_MODE_MOUSE:
282 data->wanted_bits = MCIR2_MOUSE_NBITS;
283 break;
284 default:
285 IR_dprintk(1, "not keyboard or mouse data\n");
286 goto out;
287 }
288
289 data->count = 0;
290 data->body = 0;
291 data->state = STATE_BODY_BIT_START;
292 goto again;
293
294 case STATE_BODY_BIT_START:
295 if (geq_margin(ev.duration, MCIR2_MAX_LEN, MCIR2_UNIT / 2))
296 break;
297
298 data->body <<= 1;
299 if (ev.pulse)
300 data->body |= 1;
301 data->count++;
302 data->state = STATE_BODY_BIT_END;
303 return 0;
304
305 case STATE_BODY_BIT_END:
306 if (!is_transition(&ev, &dev->raw->prev_ev))
307 break;
308
309 if (data->count == data->wanted_bits)
310 data->state = STATE_FINISHED;
311 else
312 data->state = STATE_BODY_BIT_START;
313
314 decrease_duration(&ev, MCIR2_BIT_END);
315 goto again;
316
317 case STATE_FINISHED:
318 if (ev.pulse)
319 break;
320
321 switch (data->wanted_bits) {
322 case MCIR2_KEYBOARD_NBITS:
323 scancode = data->body & 0xffff;
324 IR_dprintk(1, "keyboard data 0x%08x\n", data->body);
325 if (dev->timeout)
326 delay = usecs_to_jiffies(dev->timeout / 1000);
327 else
328 delay = msecs_to_jiffies(100);
329 mod_timer(&data->rx_timeout, jiffies + delay);
330 /* Pass data to keyboard buffer parser */
331 ir_mce_kbd_process_keyboard_data(data->idev, scancode);
332 break;
333 case MCIR2_MOUSE_NBITS:
334 scancode = data->body & 0x1fffff;
335 IR_dprintk(1, "mouse data 0x%06x\n", scancode);
336 /* Pass data to mouse buffer parser */
337 ir_mce_kbd_process_mouse_data(data->idev, scancode);
338 break;
339 default:
340 IR_dprintk(1, "not keyboard or mouse data\n");
341 goto out;
342 }
343
344 data->state = STATE_INACTIVE;
345 input_sync(data->idev);
346 return 0;
347 }
348
349 out:
350 IR_dprintk(1, "failed at state %i (%uus %s)\n",
351 data->state, TO_US(ev.duration), TO_STR(ev.pulse));
352 data->state = STATE_INACTIVE;
353 input_sync(data->idev);
354 return -EINVAL;
355 }
356
ir_mce_kbd_register(struct rc_dev * dev)357 static int ir_mce_kbd_register(struct rc_dev *dev)
358 {
359 struct mce_kbd_dec *mce_kbd = &dev->raw->mce_kbd;
360 struct input_dev *idev;
361 int i, ret;
362
363 idev = input_allocate_device();
364 if (!idev)
365 return -ENOMEM;
366
367 snprintf(mce_kbd->name, sizeof(mce_kbd->name),
368 "MCE IR Keyboard/Mouse (%s)", dev->driver_name);
369 strlcat(mce_kbd->phys, "/input0", sizeof(mce_kbd->phys));
370
371 idev->name = mce_kbd->name;
372 idev->phys = mce_kbd->phys;
373
374 /* Keyboard bits */
375 set_bit(EV_KEY, idev->evbit);
376 set_bit(EV_REP, idev->evbit);
377 for (i = 0; i < sizeof(kbd_keycodes); i++)
378 set_bit(kbd_keycodes[i], idev->keybit);
379
380 /* Mouse bits */
381 set_bit(EV_REL, idev->evbit);
382 set_bit(REL_X, idev->relbit);
383 set_bit(REL_Y, idev->relbit);
384 set_bit(BTN_LEFT, idev->keybit);
385 set_bit(BTN_RIGHT, idev->keybit);
386
387 /* Report scancodes too */
388 set_bit(EV_MSC, idev->evbit);
389 set_bit(MSC_SCAN, idev->mscbit);
390
391 setup_timer(&mce_kbd->rx_timeout, mce_kbd_rx_timeout,
392 (unsigned long)mce_kbd);
393
394 input_set_drvdata(idev, mce_kbd);
395
396 #if 0
397 /* Adding this reference means two input devices are associated with
398 * this rc-core device, which ir-keytable doesn't cope with yet */
399 idev->dev.parent = &dev->dev;
400 #endif
401
402 ret = input_register_device(idev);
403 if (ret < 0) {
404 input_free_device(idev);
405 return -EIO;
406 }
407
408 mce_kbd->idev = idev;
409
410 return 0;
411 }
412
ir_mce_kbd_unregister(struct rc_dev * dev)413 static int ir_mce_kbd_unregister(struct rc_dev *dev)
414 {
415 struct mce_kbd_dec *mce_kbd = &dev->raw->mce_kbd;
416 struct input_dev *idev = mce_kbd->idev;
417
418 del_timer_sync(&mce_kbd->rx_timeout);
419 input_unregister_device(idev);
420
421 return 0;
422 }
423
424 static struct ir_raw_handler mce_kbd_handler = {
425 .protocols = RC_BIT_MCE_KBD,
426 .decode = ir_mce_kbd_decode,
427 .raw_register = ir_mce_kbd_register,
428 .raw_unregister = ir_mce_kbd_unregister,
429 };
430
ir_mce_kbd_decode_init(void)431 static int __init ir_mce_kbd_decode_init(void)
432 {
433 ir_raw_handler_register(&mce_kbd_handler);
434
435 printk(KERN_INFO "IR MCE Keyboard/mouse protocol handler initialized\n");
436 return 0;
437 }
438
ir_mce_kbd_decode_exit(void)439 static void __exit ir_mce_kbd_decode_exit(void)
440 {
441 ir_raw_handler_unregister(&mce_kbd_handler);
442 }
443
444 module_init(ir_mce_kbd_decode_init);
445 module_exit(ir_mce_kbd_decode_exit);
446
447 MODULE_LICENSE("GPL");
448 MODULE_AUTHOR("Jarod Wilson <jarod@redhat.com>");
449 MODULE_DESCRIPTION("MCE Keyboard/mouse IR protocol decoder");
450