1 /* 2 * MIDI byte <-> sequencer event coder 3 * 4 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>, 5 * Jaroslav Kysela <perex@suse.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 <sound/driver.h> 23 #include <linux/slab.h> 24 #include <linux/errno.h> 25 #include <linux/string.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@suse.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 } 137 138 void snd_midi_event_free(struct snd_midi_event *dev) 139 { 140 if (dev != NULL) { 141 kfree(dev->buf); 142 kfree(dev); 143 } 144 } 145 146 /* 147 * initialize record 148 */ 149 static inline void reset_encode(struct snd_midi_event *dev) 150 { 151 dev->read = 0; 152 dev->qlen = 0; 153 dev->type = ST_INVALID; 154 } 155 156 void snd_midi_event_reset_encode(struct snd_midi_event *dev) 157 { 158 unsigned long flags; 159 160 spin_lock_irqsave(&dev->lock, flags); 161 reset_encode(dev); 162 spin_unlock_irqrestore(&dev->lock, flags); 163 } 164 165 void snd_midi_event_reset_decode(struct snd_midi_event *dev) 166 { 167 unsigned long flags; 168 169 spin_lock_irqsave(&dev->lock, flags); 170 dev->lastcmd = 0xff; 171 spin_unlock_irqrestore(&dev->lock, flags); 172 } 173 174 #if 0 175 void snd_midi_event_init(struct snd_midi_event *dev) 176 { 177 snd_midi_event_reset_encode(dev); 178 snd_midi_event_reset_decode(dev); 179 } 180 #endif /* 0 */ 181 182 void snd_midi_event_no_status(struct snd_midi_event *dev, int on) 183 { 184 dev->nostat = on ? 1 : 0; 185 } 186 187 /* 188 * resize buffer 189 */ 190 #if 0 191 int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize) 192 { 193 unsigned char *new_buf, *old_buf; 194 unsigned long flags; 195 196 if (bufsize == dev->bufsize) 197 return 0; 198 new_buf = kmalloc(bufsize, GFP_KERNEL); 199 if (new_buf == NULL) 200 return -ENOMEM; 201 spin_lock_irqsave(&dev->lock, flags); 202 old_buf = dev->buf; 203 dev->buf = new_buf; 204 dev->bufsize = bufsize; 205 reset_encode(dev); 206 spin_unlock_irqrestore(&dev->lock, flags); 207 kfree(old_buf); 208 return 0; 209 } 210 #endif /* 0 */ 211 212 /* 213 * read bytes and encode to sequencer event if finished 214 * return the size of encoded bytes 215 */ 216 long snd_midi_event_encode(struct snd_midi_event *dev, unsigned char *buf, long count, 217 struct snd_seq_event *ev) 218 { 219 long result = 0; 220 int rc; 221 222 ev->type = SNDRV_SEQ_EVENT_NONE; 223 224 while (count-- > 0) { 225 rc = snd_midi_event_encode_byte(dev, *buf++, ev); 226 result++; 227 if (rc < 0) 228 return rc; 229 else if (rc > 0) 230 return result; 231 } 232 233 return result; 234 } 235 236 /* 237 * read one byte and encode to sequencer event: 238 * return 1 if MIDI bytes are encoded to an event 239 * 0 data is not finished 240 * negative for error 241 */ 242 int snd_midi_event_encode_byte(struct snd_midi_event *dev, int c, 243 struct snd_seq_event *ev) 244 { 245 int rc = 0; 246 unsigned long flags; 247 248 c &= 0xff; 249 250 if (c >= MIDI_CMD_COMMON_CLOCK) { 251 /* real-time event */ 252 ev->type = status_event[ST_SPECIAL + c - 0xf0].event; 253 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 254 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 255 return 1; 256 } 257 258 spin_lock_irqsave(&dev->lock, flags); 259 if ((c & 0x80) && 260 (c != MIDI_CMD_COMMON_SYSEX_END || dev->type != ST_SYSEX)) { 261 /* new command */ 262 dev->buf[0] = c; 263 if ((c & 0xf0) == 0xf0) /* system messages */ 264 dev->type = (c & 0x0f) + ST_SPECIAL; 265 else 266 dev->type = (c >> 4) & 0x07; 267 dev->read = 1; 268 dev->qlen = status_event[dev->type].qlen; 269 } else { 270 if (dev->qlen > 0) { 271 /* rest of command */ 272 dev->buf[dev->read++] = c; 273 if (dev->type != ST_SYSEX) 274 dev->qlen--; 275 } else { 276 /* running status */ 277 dev->buf[1] = c; 278 dev->qlen = status_event[dev->type].qlen - 1; 279 dev->read = 2; 280 } 281 } 282 if (dev->qlen == 0) { 283 ev->type = status_event[dev->type].event; 284 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 285 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 286 if (status_event[dev->type].encode) /* set data values */ 287 status_event[dev->type].encode(dev, ev); 288 if (dev->type >= ST_SPECIAL) 289 dev->type = ST_INVALID; 290 rc = 1; 291 } else if (dev->type == ST_SYSEX) { 292 if (c == MIDI_CMD_COMMON_SYSEX_END || 293 dev->read >= dev->bufsize) { 294 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 295 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE; 296 ev->type = SNDRV_SEQ_EVENT_SYSEX; 297 ev->data.ext.len = dev->read; 298 ev->data.ext.ptr = dev->buf; 299 if (c != MIDI_CMD_COMMON_SYSEX_END) 300 dev->read = 0; /* continue to parse */ 301 else 302 reset_encode(dev); /* all parsed */ 303 rc = 1; 304 } 305 } 306 307 spin_unlock_irqrestore(&dev->lock, flags); 308 return rc; 309 } 310 311 /* encode note event */ 312 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 313 { 314 ev->data.note.channel = dev->buf[0] & 0x0f; 315 ev->data.note.note = dev->buf[1]; 316 ev->data.note.velocity = dev->buf[2]; 317 } 318 319 /* encode one parameter controls */ 320 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 321 { 322 ev->data.control.channel = dev->buf[0] & 0x0f; 323 ev->data.control.value = dev->buf[1]; 324 } 325 326 /* encode pitch wheel change */ 327 static void pitchbend_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 = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192; 331 } 332 333 /* encode midi control change */ 334 static void two_param_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.param = dev->buf[1]; 338 ev->data.control.value = dev->buf[2]; 339 } 340 341 /* encode one parameter value*/ 342 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 343 { 344 ev->data.control.value = dev->buf[1]; 345 } 346 347 /* encode song position */ 348 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 349 { 350 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1]; 351 } 352 353 /* 354 * decode from a sequencer event to midi bytes 355 * return the size of decoded midi events 356 */ 357 long snd_midi_event_decode(struct snd_midi_event *dev, unsigned char *buf, long count, 358 struct snd_seq_event *ev) 359 { 360 unsigned int cmd, type; 361 362 if (ev->type == SNDRV_SEQ_EVENT_NONE) 363 return -ENOENT; 364 365 for (type = 0; type < ARRAY_SIZE(status_event); type++) { 366 if (ev->type == status_event[type].event) 367 goto __found; 368 } 369 for (type = 0; type < ARRAY_SIZE(extra_event); type++) { 370 if (ev->type == extra_event[type].event) 371 return extra_event[type].decode(dev, buf, count, ev); 372 } 373 return -ENOENT; 374 375 __found: 376 if (type >= ST_SPECIAL) 377 cmd = 0xf0 + (type - ST_SPECIAL); 378 else 379 /* data.note.channel and data.control.channel is identical */ 380 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f); 381 382 383 if (cmd == MIDI_CMD_COMMON_SYSEX) { 384 snd_midi_event_reset_decode(dev); 385 return snd_seq_expand_var_event(ev, count, buf, 1, 0); 386 } else { 387 int qlen; 388 unsigned char xbuf[4]; 389 unsigned long flags; 390 391 spin_lock_irqsave(&dev->lock, flags); 392 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) { 393 dev->lastcmd = cmd; 394 spin_unlock_irqrestore(&dev->lock, flags); 395 xbuf[0] = cmd; 396 if (status_event[type].decode) 397 status_event[type].decode(ev, xbuf + 1); 398 qlen = status_event[type].qlen + 1; 399 } else { 400 spin_unlock_irqrestore(&dev->lock, flags); 401 if (status_event[type].decode) 402 status_event[type].decode(ev, xbuf + 0); 403 qlen = status_event[type].qlen; 404 } 405 if (count < qlen) 406 return -ENOMEM; 407 memcpy(buf, xbuf, qlen); 408 return qlen; 409 } 410 } 411 412 413 /* decode note event */ 414 static void note_decode(struct snd_seq_event *ev, unsigned char *buf) 415 { 416 buf[0] = ev->data.note.note & 0x7f; 417 buf[1] = ev->data.note.velocity & 0x7f; 418 } 419 420 /* decode one parameter controls */ 421 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf) 422 { 423 buf[0] = ev->data.control.value & 0x7f; 424 } 425 426 /* decode pitch wheel change */ 427 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf) 428 { 429 int value = ev->data.control.value + 8192; 430 buf[0] = value & 0x7f; 431 buf[1] = (value >> 7) & 0x7f; 432 } 433 434 /* decode midi control change */ 435 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf) 436 { 437 buf[0] = ev->data.control.param & 0x7f; 438 buf[1] = ev->data.control.value & 0x7f; 439 } 440 441 /* decode song position */ 442 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf) 443 { 444 buf[0] = ev->data.control.value & 0x7f; 445 buf[1] = (ev->data.control.value >> 7) & 0x7f; 446 } 447 448 /* decode 14bit control */ 449 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, 450 int count, struct snd_seq_event *ev) 451 { 452 unsigned char cmd; 453 int idx = 0; 454 455 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 456 if (ev->data.control.param < 0x20) { 457 if (count < 4) 458 return -ENOMEM; 459 if (dev->nostat && count < 6) 460 return -ENOMEM; 461 if (cmd != dev->lastcmd || dev->nostat) { 462 if (count < 5) 463 return -ENOMEM; 464 buf[idx++] = dev->lastcmd = cmd; 465 } 466 buf[idx++] = ev->data.control.param; 467 buf[idx++] = (ev->data.control.value >> 7) & 0x7f; 468 if (dev->nostat) 469 buf[idx++] = cmd; 470 buf[idx++] = ev->data.control.param + 0x20; 471 buf[idx++] = ev->data.control.value & 0x7f; 472 } else { 473 if (count < 2) 474 return -ENOMEM; 475 if (cmd != dev->lastcmd || dev->nostat) { 476 if (count < 3) 477 return -ENOMEM; 478 buf[idx++] = dev->lastcmd = cmd; 479 } 480 buf[idx++] = ev->data.control.param & 0x7f; 481 buf[idx++] = ev->data.control.value & 0x7f; 482 } 483 return idx; 484 } 485 486 /* decode reg/nonreg param */ 487 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, 488 int count, struct snd_seq_event *ev) 489 { 490 unsigned char cmd; 491 char *cbytes; 492 static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB, 493 MIDI_CTL_NONREG_PARM_NUM_LSB, 494 MIDI_CTL_MSB_DATA_ENTRY, 495 MIDI_CTL_LSB_DATA_ENTRY }; 496 static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB, 497 MIDI_CTL_REGIST_PARM_NUM_LSB, 498 MIDI_CTL_MSB_DATA_ENTRY, 499 MIDI_CTL_LSB_DATA_ENTRY }; 500 unsigned char bytes[4]; 501 int idx = 0, i; 502 503 if (count < 8) 504 return -ENOMEM; 505 if (dev->nostat && count < 12) 506 return -ENOMEM; 507 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 508 bytes[0] = ev->data.control.param & 0x007f; 509 bytes[1] = (ev->data.control.param & 0x3f80) >> 7; 510 bytes[2] = ev->data.control.value & 0x007f; 511 bytes[3] = (ev->data.control.value & 0x3f80) >> 7; 512 if (cmd != dev->lastcmd && !dev->nostat) { 513 if (count < 9) 514 return -ENOMEM; 515 buf[idx++] = dev->lastcmd = cmd; 516 } 517 cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn; 518 for (i = 0; i < 4; i++) { 519 if (dev->nostat) 520 buf[idx++] = dev->lastcmd = cmd; 521 buf[idx++] = cbytes[i]; 522 buf[idx++] = bytes[i]; 523 } 524 return idx; 525 } 526 527 /* 528 * exports 529 */ 530 531 EXPORT_SYMBOL(snd_midi_event_new); 532 EXPORT_SYMBOL(snd_midi_event_free); 533 EXPORT_SYMBOL(snd_midi_event_reset_encode); 534 EXPORT_SYMBOL(snd_midi_event_reset_decode); 535 EXPORT_SYMBOL(snd_midi_event_no_status); 536 EXPORT_SYMBOL(snd_midi_event_encode); 537 EXPORT_SYMBOL(snd_midi_event_encode_byte); 538 EXPORT_SYMBOL(snd_midi_event_decode); 539 540 static int __init alsa_seq_midi_event_init(void) 541 { 542 return 0; 543 } 544 545 static void __exit alsa_seq_midi_event_exit(void) 546 { 547 } 548 549 module_init(alsa_seq_midi_event_init) 550 module_exit(alsa_seq_midi_event_exit) 551