1 /* 2 * MIDI byte <-> sequencer event coder 3 * 4 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>, 5 * Jaroslav Kysela <perex@perex.cz> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 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 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 #include <linux/slab.h> 23 #include <linux/errno.h> 24 #include <linux/string.h> 25 #include <linux/module.h> 26 #include <sound/core.h> 27 #include <sound/seq_kernel.h> 28 #include <sound/seq_midi_event.h> 29 #include <sound/asoundef.h> 30 31 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>"); 32 MODULE_DESCRIPTION("MIDI byte <-> sequencer event coder"); 33 MODULE_LICENSE("GPL"); 34 35 /* event type, index into status_event[] */ 36 /* from 0 to 6 are normal commands (note off, on, etc.) for 0x9?-0xe? */ 37 #define ST_INVALID 7 38 #define ST_SPECIAL 8 39 #define ST_SYSEX ST_SPECIAL 40 /* from 8 to 15 are events for 0xf0-0xf7 */ 41 42 43 /* 44 * prototypes 45 */ 46 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 47 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 48 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 49 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 50 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 51 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 52 static void note_decode(struct snd_seq_event *ev, unsigned char *buf); 53 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf); 54 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf); 55 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf); 56 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf); 57 58 /* 59 * event list 60 */ 61 static struct status_event_list { 62 int event; 63 int qlen; 64 void (*encode)(struct snd_midi_event *dev, struct snd_seq_event *ev); 65 void (*decode)(struct snd_seq_event *ev, unsigned char *buf); 66 } status_event[] = { 67 /* 0x80 - 0xef */ 68 {SNDRV_SEQ_EVENT_NOTEOFF, 2, note_event, note_decode}, 69 {SNDRV_SEQ_EVENT_NOTEON, 2, note_event, note_decode}, 70 {SNDRV_SEQ_EVENT_KEYPRESS, 2, note_event, note_decode}, 71 {SNDRV_SEQ_EVENT_CONTROLLER, 2, two_param_ctrl_event, two_param_decode}, 72 {SNDRV_SEQ_EVENT_PGMCHANGE, 1, one_param_ctrl_event, one_param_decode}, 73 {SNDRV_SEQ_EVENT_CHANPRESS, 1, one_param_ctrl_event, one_param_decode}, 74 {SNDRV_SEQ_EVENT_PITCHBEND, 2, pitchbend_ctrl_event, pitchbend_decode}, 75 /* invalid */ 76 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, 77 /* 0xf0 - 0xff */ 78 {SNDRV_SEQ_EVENT_SYSEX, 1, NULL, NULL}, /* sysex: 0xf0 */ 79 {SNDRV_SEQ_EVENT_QFRAME, 1, one_param_event, one_param_decode}, /* 0xf1 */ 80 {SNDRV_SEQ_EVENT_SONGPOS, 2, songpos_event, songpos_decode}, /* 0xf2 */ 81 {SNDRV_SEQ_EVENT_SONGSEL, 1, one_param_event, one_param_decode}, /* 0xf3 */ 82 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf4 */ 83 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf5 */ 84 {SNDRV_SEQ_EVENT_TUNE_REQUEST, 0, NULL, NULL}, /* 0xf6 */ 85 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf7 */ 86 {SNDRV_SEQ_EVENT_CLOCK, 0, NULL, NULL}, /* 0xf8 */ 87 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf9 */ 88 {SNDRV_SEQ_EVENT_START, 0, NULL, NULL}, /* 0xfa */ 89 {SNDRV_SEQ_EVENT_CONTINUE, 0, NULL, NULL}, /* 0xfb */ 90 {SNDRV_SEQ_EVENT_STOP, 0, NULL, NULL}, /* 0xfc */ 91 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xfd */ 92 {SNDRV_SEQ_EVENT_SENSING, 0, NULL, NULL}, /* 0xfe */ 93 {SNDRV_SEQ_EVENT_RESET, 0, NULL, NULL}, /* 0xff */ 94 }; 95 96 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, int len, 97 struct snd_seq_event *ev); 98 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, int count, 99 struct snd_seq_event *ev); 100 101 static struct extra_event_list { 102 int event; 103 int (*decode)(struct snd_midi_event *dev, unsigned char *buf, int len, 104 struct snd_seq_event *ev); 105 } extra_event[] = { 106 {SNDRV_SEQ_EVENT_CONTROL14, extra_decode_ctrl14}, 107 {SNDRV_SEQ_EVENT_NONREGPARAM, extra_decode_xrpn}, 108 {SNDRV_SEQ_EVENT_REGPARAM, extra_decode_xrpn}, 109 }; 110 111 /* 112 * new/delete record 113 */ 114 115 int snd_midi_event_new(int bufsize, struct snd_midi_event **rdev) 116 { 117 struct snd_midi_event *dev; 118 119 *rdev = NULL; 120 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 121 if (dev == NULL) 122 return -ENOMEM; 123 if (bufsize > 0) { 124 dev->buf = kmalloc(bufsize, GFP_KERNEL); 125 if (dev->buf == NULL) { 126 kfree(dev); 127 return -ENOMEM; 128 } 129 } 130 dev->bufsize = bufsize; 131 dev->lastcmd = 0xff; 132 dev->type = ST_INVALID; 133 spin_lock_init(&dev->lock); 134 *rdev = dev; 135 return 0; 136 } 137 EXPORT_SYMBOL(snd_midi_event_new); 138 139 void snd_midi_event_free(struct snd_midi_event *dev) 140 { 141 if (dev != NULL) { 142 kfree(dev->buf); 143 kfree(dev); 144 } 145 } 146 EXPORT_SYMBOL(snd_midi_event_free); 147 148 /* 149 * initialize record 150 */ 151 static inline void reset_encode(struct snd_midi_event *dev) 152 { 153 dev->read = 0; 154 dev->qlen = 0; 155 dev->type = ST_INVALID; 156 } 157 158 void snd_midi_event_reset_encode(struct snd_midi_event *dev) 159 { 160 unsigned long flags; 161 162 spin_lock_irqsave(&dev->lock, flags); 163 reset_encode(dev); 164 spin_unlock_irqrestore(&dev->lock, flags); 165 } 166 EXPORT_SYMBOL(snd_midi_event_reset_encode); 167 168 void snd_midi_event_reset_decode(struct snd_midi_event *dev) 169 { 170 unsigned long flags; 171 172 spin_lock_irqsave(&dev->lock, flags); 173 dev->lastcmd = 0xff; 174 spin_unlock_irqrestore(&dev->lock, flags); 175 } 176 EXPORT_SYMBOL(snd_midi_event_reset_decode); 177 178 #if 0 179 void snd_midi_event_init(struct snd_midi_event *dev) 180 { 181 snd_midi_event_reset_encode(dev); 182 snd_midi_event_reset_decode(dev); 183 } 184 #endif /* 0 */ 185 186 void snd_midi_event_no_status(struct snd_midi_event *dev, int on) 187 { 188 dev->nostat = on ? 1 : 0; 189 } 190 EXPORT_SYMBOL(snd_midi_event_no_status); 191 192 /* 193 * resize buffer 194 */ 195 #if 0 196 int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize) 197 { 198 unsigned char *new_buf, *old_buf; 199 unsigned long flags; 200 201 if (bufsize == dev->bufsize) 202 return 0; 203 new_buf = kmalloc(bufsize, GFP_KERNEL); 204 if (new_buf == NULL) 205 return -ENOMEM; 206 spin_lock_irqsave(&dev->lock, flags); 207 old_buf = dev->buf; 208 dev->buf = new_buf; 209 dev->bufsize = bufsize; 210 reset_encode(dev); 211 spin_unlock_irqrestore(&dev->lock, flags); 212 kfree(old_buf); 213 return 0; 214 } 215 #endif /* 0 */ 216 217 /* 218 * read bytes and encode to sequencer event if finished 219 * return the size of encoded bytes 220 */ 221 long snd_midi_event_encode(struct snd_midi_event *dev, unsigned char *buf, long count, 222 struct snd_seq_event *ev) 223 { 224 long result = 0; 225 int rc; 226 227 ev->type = SNDRV_SEQ_EVENT_NONE; 228 229 while (count-- > 0) { 230 rc = snd_midi_event_encode_byte(dev, *buf++, ev); 231 result++; 232 if (rc < 0) 233 return rc; 234 else if (rc > 0) 235 return result; 236 } 237 238 return result; 239 } 240 EXPORT_SYMBOL(snd_midi_event_encode); 241 242 /* 243 * read one byte and encode to sequencer event: 244 * return 1 if MIDI bytes are encoded to an event 245 * 0 data is not finished 246 * negative for error 247 */ 248 int snd_midi_event_encode_byte(struct snd_midi_event *dev, int c, 249 struct snd_seq_event *ev) 250 { 251 int rc = 0; 252 unsigned long flags; 253 254 c &= 0xff; 255 256 if (c >= MIDI_CMD_COMMON_CLOCK) { 257 /* real-time event */ 258 ev->type = status_event[ST_SPECIAL + c - 0xf0].event; 259 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 260 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 261 return ev->type != SNDRV_SEQ_EVENT_NONE; 262 } 263 264 spin_lock_irqsave(&dev->lock, flags); 265 if ((c & 0x80) && 266 (c != MIDI_CMD_COMMON_SYSEX_END || dev->type != ST_SYSEX)) { 267 /* new command */ 268 dev->buf[0] = c; 269 if ((c & 0xf0) == 0xf0) /* system messages */ 270 dev->type = (c & 0x0f) + ST_SPECIAL; 271 else 272 dev->type = (c >> 4) & 0x07; 273 dev->read = 1; 274 dev->qlen = status_event[dev->type].qlen; 275 } else { 276 if (dev->qlen > 0) { 277 /* rest of command */ 278 dev->buf[dev->read++] = c; 279 if (dev->type != ST_SYSEX) 280 dev->qlen--; 281 } else { 282 /* running status */ 283 dev->buf[1] = c; 284 dev->qlen = status_event[dev->type].qlen - 1; 285 dev->read = 2; 286 } 287 } 288 if (dev->qlen == 0) { 289 ev->type = status_event[dev->type].event; 290 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 291 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 292 if (status_event[dev->type].encode) /* set data values */ 293 status_event[dev->type].encode(dev, ev); 294 if (dev->type >= ST_SPECIAL) 295 dev->type = ST_INVALID; 296 rc = 1; 297 } else if (dev->type == ST_SYSEX) { 298 if (c == MIDI_CMD_COMMON_SYSEX_END || 299 dev->read >= dev->bufsize) { 300 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 301 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE; 302 ev->type = SNDRV_SEQ_EVENT_SYSEX; 303 ev->data.ext.len = dev->read; 304 ev->data.ext.ptr = dev->buf; 305 if (c != MIDI_CMD_COMMON_SYSEX_END) 306 dev->read = 0; /* continue to parse */ 307 else 308 reset_encode(dev); /* all parsed */ 309 rc = 1; 310 } 311 } 312 313 spin_unlock_irqrestore(&dev->lock, flags); 314 return rc; 315 } 316 EXPORT_SYMBOL(snd_midi_event_encode_byte); 317 318 /* encode note event */ 319 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 320 { 321 ev->data.note.channel = dev->buf[0] & 0x0f; 322 ev->data.note.note = dev->buf[1]; 323 ev->data.note.velocity = dev->buf[2]; 324 } 325 326 /* encode one parameter controls */ 327 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 328 { 329 ev->data.control.channel = dev->buf[0] & 0x0f; 330 ev->data.control.value = dev->buf[1]; 331 } 332 333 /* encode pitch wheel change */ 334 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 335 { 336 ev->data.control.channel = dev->buf[0] & 0x0f; 337 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192; 338 } 339 340 /* encode midi control change */ 341 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 342 { 343 ev->data.control.channel = dev->buf[0] & 0x0f; 344 ev->data.control.param = dev->buf[1]; 345 ev->data.control.value = dev->buf[2]; 346 } 347 348 /* encode one parameter value*/ 349 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 350 { 351 ev->data.control.value = dev->buf[1]; 352 } 353 354 /* encode song position */ 355 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 356 { 357 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1]; 358 } 359 360 /* 361 * decode from a sequencer event to midi bytes 362 * return the size of decoded midi events 363 */ 364 long snd_midi_event_decode(struct snd_midi_event *dev, unsigned char *buf, long count, 365 struct snd_seq_event *ev) 366 { 367 unsigned int cmd, type; 368 369 if (ev->type == SNDRV_SEQ_EVENT_NONE) 370 return -ENOENT; 371 372 for (type = 0; type < ARRAY_SIZE(status_event); type++) { 373 if (ev->type == status_event[type].event) 374 goto __found; 375 } 376 for (type = 0; type < ARRAY_SIZE(extra_event); type++) { 377 if (ev->type == extra_event[type].event) 378 return extra_event[type].decode(dev, buf, count, ev); 379 } 380 return -ENOENT; 381 382 __found: 383 if (type >= ST_SPECIAL) 384 cmd = 0xf0 + (type - ST_SPECIAL); 385 else 386 /* data.note.channel and data.control.channel is identical */ 387 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f); 388 389 390 if (cmd == MIDI_CMD_COMMON_SYSEX) { 391 snd_midi_event_reset_decode(dev); 392 return snd_seq_expand_var_event(ev, count, buf, 1, 0); 393 } else { 394 int qlen; 395 unsigned char xbuf[4]; 396 unsigned long flags; 397 398 spin_lock_irqsave(&dev->lock, flags); 399 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) { 400 dev->lastcmd = cmd; 401 spin_unlock_irqrestore(&dev->lock, flags); 402 xbuf[0] = cmd; 403 if (status_event[type].decode) 404 status_event[type].decode(ev, xbuf + 1); 405 qlen = status_event[type].qlen + 1; 406 } else { 407 spin_unlock_irqrestore(&dev->lock, flags); 408 if (status_event[type].decode) 409 status_event[type].decode(ev, xbuf + 0); 410 qlen = status_event[type].qlen; 411 } 412 if (count < qlen) 413 return -ENOMEM; 414 memcpy(buf, xbuf, qlen); 415 return qlen; 416 } 417 } 418 EXPORT_SYMBOL(snd_midi_event_decode); 419 420 421 /* decode note event */ 422 static void note_decode(struct snd_seq_event *ev, unsigned char *buf) 423 { 424 buf[0] = ev->data.note.note & 0x7f; 425 buf[1] = ev->data.note.velocity & 0x7f; 426 } 427 428 /* decode one parameter controls */ 429 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf) 430 { 431 buf[0] = ev->data.control.value & 0x7f; 432 } 433 434 /* decode pitch wheel change */ 435 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf) 436 { 437 int value = ev->data.control.value + 8192; 438 buf[0] = value & 0x7f; 439 buf[1] = (value >> 7) & 0x7f; 440 } 441 442 /* decode midi control change */ 443 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf) 444 { 445 buf[0] = ev->data.control.param & 0x7f; 446 buf[1] = ev->data.control.value & 0x7f; 447 } 448 449 /* decode song position */ 450 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf) 451 { 452 buf[0] = ev->data.control.value & 0x7f; 453 buf[1] = (ev->data.control.value >> 7) & 0x7f; 454 } 455 456 /* decode 14bit control */ 457 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, 458 int count, struct snd_seq_event *ev) 459 { 460 unsigned char cmd; 461 int idx = 0; 462 463 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 464 if (ev->data.control.param < 0x20) { 465 if (count < 4) 466 return -ENOMEM; 467 if (dev->nostat && count < 6) 468 return -ENOMEM; 469 if (cmd != dev->lastcmd || dev->nostat) { 470 if (count < 5) 471 return -ENOMEM; 472 buf[idx++] = dev->lastcmd = cmd; 473 } 474 buf[idx++] = ev->data.control.param; 475 buf[idx++] = (ev->data.control.value >> 7) & 0x7f; 476 if (dev->nostat) 477 buf[idx++] = cmd; 478 buf[idx++] = ev->data.control.param + 0x20; 479 buf[idx++] = ev->data.control.value & 0x7f; 480 } else { 481 if (count < 2) 482 return -ENOMEM; 483 if (cmd != dev->lastcmd || dev->nostat) { 484 if (count < 3) 485 return -ENOMEM; 486 buf[idx++] = dev->lastcmd = cmd; 487 } 488 buf[idx++] = ev->data.control.param & 0x7f; 489 buf[idx++] = ev->data.control.value & 0x7f; 490 } 491 return idx; 492 } 493 494 /* decode reg/nonreg param */ 495 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, 496 int count, struct snd_seq_event *ev) 497 { 498 unsigned char cmd; 499 char *cbytes; 500 static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB, 501 MIDI_CTL_NONREG_PARM_NUM_LSB, 502 MIDI_CTL_MSB_DATA_ENTRY, 503 MIDI_CTL_LSB_DATA_ENTRY }; 504 static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB, 505 MIDI_CTL_REGIST_PARM_NUM_LSB, 506 MIDI_CTL_MSB_DATA_ENTRY, 507 MIDI_CTL_LSB_DATA_ENTRY }; 508 unsigned char bytes[4]; 509 int idx = 0, i; 510 511 if (count < 8) 512 return -ENOMEM; 513 if (dev->nostat && count < 12) 514 return -ENOMEM; 515 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 516 bytes[0] = (ev->data.control.param & 0x3f80) >> 7; 517 bytes[1] = ev->data.control.param & 0x007f; 518 bytes[2] = (ev->data.control.value & 0x3f80) >> 7; 519 bytes[3] = ev->data.control.value & 0x007f; 520 if (cmd != dev->lastcmd && !dev->nostat) { 521 if (count < 9) 522 return -ENOMEM; 523 buf[idx++] = dev->lastcmd = cmd; 524 } 525 cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn; 526 for (i = 0; i < 4; i++) { 527 if (dev->nostat) 528 buf[idx++] = dev->lastcmd = cmd; 529 buf[idx++] = cbytes[i]; 530 buf[idx++] = bytes[i]; 531 } 532 return idx; 533 } 534 535 static int __init alsa_seq_midi_event_init(void) 536 { 537 return 0; 538 } 539 540 static void __exit alsa_seq_midi_event_exit(void) 541 { 542 } 543 544 module_init(alsa_seq_midi_event_init) 545 module_exit(alsa_seq_midi_event_exit) 546