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 <sound/core.h> 26 #include <sound/seq_kernel.h> 27 #include <sound/seq_midi_event.h> 28 #include <sound/asoundef.h> 29 30 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>"); 31 MODULE_DESCRIPTION("MIDI byte <-> sequencer event coder"); 32 MODULE_LICENSE("GPL"); 33 34 /* event type, index into status_event[] */ 35 /* from 0 to 6 are normal commands (note off, on, etc.) for 0x9?-0xe? */ 36 #define ST_INVALID 7 37 #define ST_SPECIAL 8 38 #define ST_SYSEX ST_SPECIAL 39 /* from 8 to 15 are events for 0xf0-0xf7 */ 40 41 42 /* 43 * prototypes 44 */ 45 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 46 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 47 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 48 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 49 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 50 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 51 static void note_decode(struct snd_seq_event *ev, unsigned char *buf); 52 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf); 53 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf); 54 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf); 55 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf); 56 57 /* 58 * event list 59 */ 60 static struct status_event_list { 61 int event; 62 int qlen; 63 void (*encode)(struct snd_midi_event *dev, struct snd_seq_event *ev); 64 void (*decode)(struct snd_seq_event *ev, unsigned char *buf); 65 } status_event[] = { 66 /* 0x80 - 0xef */ 67 {SNDRV_SEQ_EVENT_NOTEOFF, 2, note_event, note_decode}, 68 {SNDRV_SEQ_EVENT_NOTEON, 2, note_event, note_decode}, 69 {SNDRV_SEQ_EVENT_KEYPRESS, 2, note_event, note_decode}, 70 {SNDRV_SEQ_EVENT_CONTROLLER, 2, two_param_ctrl_event, two_param_decode}, 71 {SNDRV_SEQ_EVENT_PGMCHANGE, 1, one_param_ctrl_event, one_param_decode}, 72 {SNDRV_SEQ_EVENT_CHANPRESS, 1, one_param_ctrl_event, one_param_decode}, 73 {SNDRV_SEQ_EVENT_PITCHBEND, 2, pitchbend_ctrl_event, pitchbend_decode}, 74 /* invalid */ 75 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, 76 /* 0xf0 - 0xff */ 77 {SNDRV_SEQ_EVENT_SYSEX, 1, NULL, NULL}, /* sysex: 0xf0 */ 78 {SNDRV_SEQ_EVENT_QFRAME, 1, one_param_event, one_param_decode}, /* 0xf1 */ 79 {SNDRV_SEQ_EVENT_SONGPOS, 2, songpos_event, songpos_decode}, /* 0xf2 */ 80 {SNDRV_SEQ_EVENT_SONGSEL, 1, one_param_event, one_param_decode}, /* 0xf3 */ 81 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf4 */ 82 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf5 */ 83 {SNDRV_SEQ_EVENT_TUNE_REQUEST, 0, NULL, NULL}, /* 0xf6 */ 84 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf7 */ 85 {SNDRV_SEQ_EVENT_CLOCK, 0, NULL, NULL}, /* 0xf8 */ 86 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf9 */ 87 {SNDRV_SEQ_EVENT_START, 0, NULL, NULL}, /* 0xfa */ 88 {SNDRV_SEQ_EVENT_CONTINUE, 0, NULL, NULL}, /* 0xfb */ 89 {SNDRV_SEQ_EVENT_STOP, 0, NULL, NULL}, /* 0xfc */ 90 {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xfd */ 91 {SNDRV_SEQ_EVENT_SENSING, 0, NULL, NULL}, /* 0xfe */ 92 {SNDRV_SEQ_EVENT_RESET, 0, NULL, NULL}, /* 0xff */ 93 }; 94 95 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, int len, 96 struct snd_seq_event *ev); 97 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, int count, 98 struct snd_seq_event *ev); 99 100 static struct extra_event_list { 101 int event; 102 int (*decode)(struct snd_midi_event *dev, unsigned char *buf, int len, 103 struct snd_seq_event *ev); 104 } extra_event[] = { 105 {SNDRV_SEQ_EVENT_CONTROL14, extra_decode_ctrl14}, 106 {SNDRV_SEQ_EVENT_NONREGPARAM, extra_decode_xrpn}, 107 {SNDRV_SEQ_EVENT_REGPARAM, extra_decode_xrpn}, 108 }; 109 110 /* 111 * new/delete record 112 */ 113 114 int snd_midi_event_new(int bufsize, struct snd_midi_event **rdev) 115 { 116 struct snd_midi_event *dev; 117 118 *rdev = NULL; 119 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 120 if (dev == NULL) 121 return -ENOMEM; 122 if (bufsize > 0) { 123 dev->buf = kmalloc(bufsize, GFP_KERNEL); 124 if (dev->buf == NULL) { 125 kfree(dev); 126 return -ENOMEM; 127 } 128 } 129 dev->bufsize = bufsize; 130 dev->lastcmd = 0xff; 131 dev->type = ST_INVALID; 132 spin_lock_init(&dev->lock); 133 *rdev = dev; 134 return 0; 135 } 136 137 void snd_midi_event_free(struct snd_midi_event *dev) 138 { 139 if (dev != NULL) { 140 kfree(dev->buf); 141 kfree(dev); 142 } 143 } 144 145 /* 146 * initialize record 147 */ 148 static inline void reset_encode(struct snd_midi_event *dev) 149 { 150 dev->read = 0; 151 dev->qlen = 0; 152 dev->type = ST_INVALID; 153 } 154 155 void snd_midi_event_reset_encode(struct snd_midi_event *dev) 156 { 157 unsigned long flags; 158 159 spin_lock_irqsave(&dev->lock, flags); 160 reset_encode(dev); 161 spin_unlock_irqrestore(&dev->lock, flags); 162 } 163 164 void snd_midi_event_reset_decode(struct snd_midi_event *dev) 165 { 166 unsigned long flags; 167 168 spin_lock_irqsave(&dev->lock, flags); 169 dev->lastcmd = 0xff; 170 spin_unlock_irqrestore(&dev->lock, flags); 171 } 172 173 #if 0 174 void snd_midi_event_init(struct snd_midi_event *dev) 175 { 176 snd_midi_event_reset_encode(dev); 177 snd_midi_event_reset_decode(dev); 178 } 179 #endif /* 0 */ 180 181 void snd_midi_event_no_status(struct snd_midi_event *dev, int on) 182 { 183 dev->nostat = on ? 1 : 0; 184 } 185 186 /* 187 * resize buffer 188 */ 189 #if 0 190 int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize) 191 { 192 unsigned char *new_buf, *old_buf; 193 unsigned long flags; 194 195 if (bufsize == dev->bufsize) 196 return 0; 197 new_buf = kmalloc(bufsize, GFP_KERNEL); 198 if (new_buf == NULL) 199 return -ENOMEM; 200 spin_lock_irqsave(&dev->lock, flags); 201 old_buf = dev->buf; 202 dev->buf = new_buf; 203 dev->bufsize = bufsize; 204 reset_encode(dev); 205 spin_unlock_irqrestore(&dev->lock, flags); 206 kfree(old_buf); 207 return 0; 208 } 209 #endif /* 0 */ 210 211 /* 212 * read bytes and encode to sequencer event if finished 213 * return the size of encoded bytes 214 */ 215 long snd_midi_event_encode(struct snd_midi_event *dev, unsigned char *buf, long count, 216 struct snd_seq_event *ev) 217 { 218 long result = 0; 219 int rc; 220 221 ev->type = SNDRV_SEQ_EVENT_NONE; 222 223 while (count-- > 0) { 224 rc = snd_midi_event_encode_byte(dev, *buf++, ev); 225 result++; 226 if (rc < 0) 227 return rc; 228 else if (rc > 0) 229 return result; 230 } 231 232 return result; 233 } 234 235 /* 236 * read one byte and encode to sequencer event: 237 * return 1 if MIDI bytes are encoded to an event 238 * 0 data is not finished 239 * negative for error 240 */ 241 int snd_midi_event_encode_byte(struct snd_midi_event *dev, int c, 242 struct snd_seq_event *ev) 243 { 244 int rc = 0; 245 unsigned long flags; 246 247 c &= 0xff; 248 249 if (c >= MIDI_CMD_COMMON_CLOCK) { 250 /* real-time event */ 251 ev->type = status_event[ST_SPECIAL + c - 0xf0].event; 252 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 253 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 254 return ev->type != SNDRV_SEQ_EVENT_NONE; 255 } 256 257 spin_lock_irqsave(&dev->lock, flags); 258 if ((c & 0x80) && 259 (c != MIDI_CMD_COMMON_SYSEX_END || dev->type != ST_SYSEX)) { 260 /* new command */ 261 dev->buf[0] = c; 262 if ((c & 0xf0) == 0xf0) /* system messages */ 263 dev->type = (c & 0x0f) + ST_SPECIAL; 264 else 265 dev->type = (c >> 4) & 0x07; 266 dev->read = 1; 267 dev->qlen = status_event[dev->type].qlen; 268 } else { 269 if (dev->qlen > 0) { 270 /* rest of command */ 271 dev->buf[dev->read++] = c; 272 if (dev->type != ST_SYSEX) 273 dev->qlen--; 274 } else { 275 /* running status */ 276 dev->buf[1] = c; 277 dev->qlen = status_event[dev->type].qlen - 1; 278 dev->read = 2; 279 } 280 } 281 if (dev->qlen == 0) { 282 ev->type = status_event[dev->type].event; 283 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 284 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 285 if (status_event[dev->type].encode) /* set data values */ 286 status_event[dev->type].encode(dev, ev); 287 if (dev->type >= ST_SPECIAL) 288 dev->type = ST_INVALID; 289 rc = 1; 290 } else if (dev->type == ST_SYSEX) { 291 if (c == MIDI_CMD_COMMON_SYSEX_END || 292 dev->read >= dev->bufsize) { 293 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 294 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE; 295 ev->type = SNDRV_SEQ_EVENT_SYSEX; 296 ev->data.ext.len = dev->read; 297 ev->data.ext.ptr = dev->buf; 298 if (c != MIDI_CMD_COMMON_SYSEX_END) 299 dev->read = 0; /* continue to parse */ 300 else 301 reset_encode(dev); /* all parsed */ 302 rc = 1; 303 } 304 } 305 306 spin_unlock_irqrestore(&dev->lock, flags); 307 return rc; 308 } 309 310 /* encode note event */ 311 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 312 { 313 ev->data.note.channel = dev->buf[0] & 0x0f; 314 ev->data.note.note = dev->buf[1]; 315 ev->data.note.velocity = dev->buf[2]; 316 } 317 318 /* encode one parameter controls */ 319 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 320 { 321 ev->data.control.channel = dev->buf[0] & 0x0f; 322 ev->data.control.value = dev->buf[1]; 323 } 324 325 /* encode pitch wheel change */ 326 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 327 { 328 ev->data.control.channel = dev->buf[0] & 0x0f; 329 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192; 330 } 331 332 /* encode midi control change */ 333 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 334 { 335 ev->data.control.channel = dev->buf[0] & 0x0f; 336 ev->data.control.param = dev->buf[1]; 337 ev->data.control.value = dev->buf[2]; 338 } 339 340 /* encode one parameter value*/ 341 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 342 { 343 ev->data.control.value = dev->buf[1]; 344 } 345 346 /* encode song position */ 347 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 348 { 349 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1]; 350 } 351 352 /* 353 * decode from a sequencer event to midi bytes 354 * return the size of decoded midi events 355 */ 356 long snd_midi_event_decode(struct snd_midi_event *dev, unsigned char *buf, long count, 357 struct snd_seq_event *ev) 358 { 359 unsigned int cmd, type; 360 361 if (ev->type == SNDRV_SEQ_EVENT_NONE) 362 return -ENOENT; 363 364 for (type = 0; type < ARRAY_SIZE(status_event); type++) { 365 if (ev->type == status_event[type].event) 366 goto __found; 367 } 368 for (type = 0; type < ARRAY_SIZE(extra_event); type++) { 369 if (ev->type == extra_event[type].event) 370 return extra_event[type].decode(dev, buf, count, ev); 371 } 372 return -ENOENT; 373 374 __found: 375 if (type >= ST_SPECIAL) 376 cmd = 0xf0 + (type - ST_SPECIAL); 377 else 378 /* data.note.channel and data.control.channel is identical */ 379 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f); 380 381 382 if (cmd == MIDI_CMD_COMMON_SYSEX) { 383 snd_midi_event_reset_decode(dev); 384 return snd_seq_expand_var_event(ev, count, buf, 1, 0); 385 } else { 386 int qlen; 387 unsigned char xbuf[4]; 388 unsigned long flags; 389 390 spin_lock_irqsave(&dev->lock, flags); 391 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) { 392 dev->lastcmd = cmd; 393 spin_unlock_irqrestore(&dev->lock, flags); 394 xbuf[0] = cmd; 395 if (status_event[type].decode) 396 status_event[type].decode(ev, xbuf + 1); 397 qlen = status_event[type].qlen + 1; 398 } else { 399 spin_unlock_irqrestore(&dev->lock, flags); 400 if (status_event[type].decode) 401 status_event[type].decode(ev, xbuf + 0); 402 qlen = status_event[type].qlen; 403 } 404 if (count < qlen) 405 return -ENOMEM; 406 memcpy(buf, xbuf, qlen); 407 return qlen; 408 } 409 } 410 411 412 /* decode note event */ 413 static void note_decode(struct snd_seq_event *ev, unsigned char *buf) 414 { 415 buf[0] = ev->data.note.note & 0x7f; 416 buf[1] = ev->data.note.velocity & 0x7f; 417 } 418 419 /* decode one parameter controls */ 420 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf) 421 { 422 buf[0] = ev->data.control.value & 0x7f; 423 } 424 425 /* decode pitch wheel change */ 426 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf) 427 { 428 int value = ev->data.control.value + 8192; 429 buf[0] = value & 0x7f; 430 buf[1] = (value >> 7) & 0x7f; 431 } 432 433 /* decode midi control change */ 434 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf) 435 { 436 buf[0] = ev->data.control.param & 0x7f; 437 buf[1] = ev->data.control.value & 0x7f; 438 } 439 440 /* decode song position */ 441 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf) 442 { 443 buf[0] = ev->data.control.value & 0x7f; 444 buf[1] = (ev->data.control.value >> 7) & 0x7f; 445 } 446 447 /* decode 14bit control */ 448 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, 449 int count, struct snd_seq_event *ev) 450 { 451 unsigned char cmd; 452 int idx = 0; 453 454 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 455 if (ev->data.control.param < 0x20) { 456 if (count < 4) 457 return -ENOMEM; 458 if (dev->nostat && count < 6) 459 return -ENOMEM; 460 if (cmd != dev->lastcmd || dev->nostat) { 461 if (count < 5) 462 return -ENOMEM; 463 buf[idx++] = dev->lastcmd = cmd; 464 } 465 buf[idx++] = ev->data.control.param; 466 buf[idx++] = (ev->data.control.value >> 7) & 0x7f; 467 if (dev->nostat) 468 buf[idx++] = cmd; 469 buf[idx++] = ev->data.control.param + 0x20; 470 buf[idx++] = ev->data.control.value & 0x7f; 471 } else { 472 if (count < 2) 473 return -ENOMEM; 474 if (cmd != dev->lastcmd || dev->nostat) { 475 if (count < 3) 476 return -ENOMEM; 477 buf[idx++] = dev->lastcmd = cmd; 478 } 479 buf[idx++] = ev->data.control.param & 0x7f; 480 buf[idx++] = ev->data.control.value & 0x7f; 481 } 482 return idx; 483 } 484 485 /* decode reg/nonreg param */ 486 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, 487 int count, struct snd_seq_event *ev) 488 { 489 unsigned char cmd; 490 char *cbytes; 491 static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB, 492 MIDI_CTL_NONREG_PARM_NUM_LSB, 493 MIDI_CTL_MSB_DATA_ENTRY, 494 MIDI_CTL_LSB_DATA_ENTRY }; 495 static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB, 496 MIDI_CTL_REGIST_PARM_NUM_LSB, 497 MIDI_CTL_MSB_DATA_ENTRY, 498 MIDI_CTL_LSB_DATA_ENTRY }; 499 unsigned char bytes[4]; 500 int idx = 0, i; 501 502 if (count < 8) 503 return -ENOMEM; 504 if (dev->nostat && count < 12) 505 return -ENOMEM; 506 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 507 bytes[0] = (ev->data.control.param & 0x3f80) >> 7; 508 bytes[1] = ev->data.control.param & 0x007f; 509 bytes[2] = (ev->data.control.value & 0x3f80) >> 7; 510 bytes[3] = ev->data.control.value & 0x007f; 511 if (cmd != dev->lastcmd && !dev->nostat) { 512 if (count < 9) 513 return -ENOMEM; 514 buf[idx++] = dev->lastcmd = cmd; 515 } 516 cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn; 517 for (i = 0; i < 4; i++) { 518 if (dev->nostat) 519 buf[idx++] = dev->lastcmd = cmd; 520 buf[idx++] = cbytes[i]; 521 buf[idx++] = bytes[i]; 522 } 523 return idx; 524 } 525 526 /* 527 * exports 528 */ 529 530 EXPORT_SYMBOL(snd_midi_event_new); 531 EXPORT_SYMBOL(snd_midi_event_free); 532 EXPORT_SYMBOL(snd_midi_event_reset_encode); 533 EXPORT_SYMBOL(snd_midi_event_reset_decode); 534 EXPORT_SYMBOL(snd_midi_event_no_status); 535 EXPORT_SYMBOL(snd_midi_event_encode); 536 EXPORT_SYMBOL(snd_midi_event_encode_byte); 537 EXPORT_SYMBOL(snd_midi_event_decode); 538 539 static int __init alsa_seq_midi_event_init(void) 540 { 541 return 0; 542 } 543 544 static void __exit alsa_seq_midi_event_exit(void) 545 { 546 } 547 548 module_init(alsa_seq_midi_event_init) 549 module_exit(alsa_seq_midi_event_exit) 550