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 30MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>"); 31MODULE_DESCRIPTION("MIDI byte <-> sequencer event coder"); 32MODULE_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 */ 45static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 46static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 47static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 48static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 49static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 50static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev); 51static void note_decode(struct snd_seq_event *ev, unsigned char *buf); 52static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf); 53static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf); 54static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf); 55static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf); 56 57/* 58 * event list 59 */ 60static 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 95static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, int len, 96 struct snd_seq_event *ev); 97static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, int count, 98 struct snd_seq_event *ev); 99 100static 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 114int 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 137void 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 */ 148static 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 155void 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 164void 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 174void snd_midi_event_no_status(struct snd_midi_event *dev, int on) 175{ 176 dev->nostat = on ? 1 : 0; 177} 178 179/* 180 * resize buffer 181 */ 182 183/* 184 * read bytes and encode to sequencer event if finished 185 * return the size of encoded bytes 186 */ 187long snd_midi_event_encode(struct snd_midi_event *dev, unsigned char *buf, long count, 188 struct snd_seq_event *ev) 189{ 190 long result = 0; 191 int rc; 192 193 ev->type = SNDRV_SEQ_EVENT_NONE; 194 195 while (count-- > 0) { 196 rc = snd_midi_event_encode_byte(dev, *buf++, ev); 197 result++; 198 if (rc < 0) 199 return rc; 200 else if (rc > 0) 201 return result; 202 } 203 204 return result; 205} 206 207/* 208 * read one byte and encode to sequencer event: 209 * return 1 if MIDI bytes are encoded to an event 210 * 0 data is not finished 211 * negative for error 212 */ 213int snd_midi_event_encode_byte(struct snd_midi_event *dev, int c, 214 struct snd_seq_event *ev) 215{ 216 int rc = 0; 217 unsigned long flags; 218 219 c &= 0xff; 220 221 if (c >= MIDI_CMD_COMMON_CLOCK) { 222 /* real-time event */ 223 ev->type = status_event[ST_SPECIAL + c - 0xf0].event; 224 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 225 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 226 return ev->type != SNDRV_SEQ_EVENT_NONE; 227 } 228 229 spin_lock_irqsave(&dev->lock, flags); 230 if ((c & 0x80) && 231 (c != MIDI_CMD_COMMON_SYSEX_END || dev->type != ST_SYSEX)) { 232 /* new command */ 233 dev->buf[0] = c; 234 if ((c & 0xf0) == 0xf0) /* system messages */ 235 dev->type = (c & 0x0f) + ST_SPECIAL; 236 else 237 dev->type = (c >> 4) & 0x07; 238 dev->read = 1; 239 dev->qlen = status_event[dev->type].qlen; 240 } else { 241 if (dev->qlen > 0) { 242 /* rest of command */ 243 dev->buf[dev->read++] = c; 244 if (dev->type != ST_SYSEX) 245 dev->qlen--; 246 } else { 247 /* running status */ 248 dev->buf[1] = c; 249 dev->qlen = status_event[dev->type].qlen - 1; 250 dev->read = 2; 251 } 252 } 253 if (dev->qlen == 0) { 254 ev->type = status_event[dev->type].event; 255 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 256 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 257 if (status_event[dev->type].encode) /* set data values */ 258 status_event[dev->type].encode(dev, ev); 259 if (dev->type >= ST_SPECIAL) 260 dev->type = ST_INVALID; 261 rc = 1; 262 } else if (dev->type == ST_SYSEX) { 263 if (c == MIDI_CMD_COMMON_SYSEX_END || 264 dev->read >= dev->bufsize) { 265 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 266 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE; 267 ev->type = SNDRV_SEQ_EVENT_SYSEX; 268 ev->data.ext.len = dev->read; 269 ev->data.ext.ptr = dev->buf; 270 if (c != MIDI_CMD_COMMON_SYSEX_END) 271 dev->read = 0; /* continue to parse */ 272 else 273 reset_encode(dev); /* all parsed */ 274 rc = 1; 275 } 276 } 277 278 spin_unlock_irqrestore(&dev->lock, flags); 279 return rc; 280} 281 282/* encode note event */ 283static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 284{ 285 ev->data.note.channel = dev->buf[0] & 0x0f; 286 ev->data.note.note = dev->buf[1]; 287 ev->data.note.velocity = dev->buf[2]; 288} 289 290/* encode one parameter controls */ 291static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 292{ 293 ev->data.control.channel = dev->buf[0] & 0x0f; 294 ev->data.control.value = dev->buf[1]; 295} 296 297/* encode pitch wheel change */ 298static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 299{ 300 ev->data.control.channel = dev->buf[0] & 0x0f; 301 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192; 302} 303 304/* encode midi control change */ 305static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 306{ 307 ev->data.control.channel = dev->buf[0] & 0x0f; 308 ev->data.control.param = dev->buf[1]; 309 ev->data.control.value = dev->buf[2]; 310} 311 312/* encode one parameter value*/ 313static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 314{ 315 ev->data.control.value = dev->buf[1]; 316} 317 318/* encode song position */ 319static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 320{ 321 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1]; 322} 323 324/* 325 * decode from a sequencer event to midi bytes 326 * return the size of decoded midi events 327 */ 328long snd_midi_event_decode(struct snd_midi_event *dev, unsigned char *buf, long count, 329 struct snd_seq_event *ev) 330{ 331 unsigned int cmd, type; 332 333 if (ev->type == SNDRV_SEQ_EVENT_NONE) 334 return -ENOENT; 335 336 for (type = 0; type < ARRAY_SIZE(status_event); type++) { 337 if (ev->type == status_event[type].event) 338 goto __found; 339 } 340 for (type = 0; type < ARRAY_SIZE(extra_event); type++) { 341 if (ev->type == extra_event[type].event) 342 return extra_event[type].decode(dev, buf, count, ev); 343 } 344 return -ENOENT; 345 346 __found: 347 if (type >= ST_SPECIAL) 348 cmd = 0xf0 + (type - ST_SPECIAL); 349 else 350 /* data.note.channel and data.control.channel is identical */ 351 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f); 352 353 354 if (cmd == MIDI_CMD_COMMON_SYSEX) { 355 snd_midi_event_reset_decode(dev); 356 return snd_seq_expand_var_event(ev, count, buf, 1, 0); 357 } else { 358 int qlen; 359 unsigned char xbuf[4]; 360 unsigned long flags; 361 362 spin_lock_irqsave(&dev->lock, flags); 363 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) { 364 dev->lastcmd = cmd; 365 spin_unlock_irqrestore(&dev->lock, flags); 366 xbuf[0] = cmd; 367 if (status_event[type].decode) 368 status_event[type].decode(ev, xbuf + 1); 369 qlen = status_event[type].qlen + 1; 370 } else { 371 spin_unlock_irqrestore(&dev->lock, flags); 372 if (status_event[type].decode) 373 status_event[type].decode(ev, xbuf + 0); 374 qlen = status_event[type].qlen; 375 } 376 if (count < qlen) 377 return -ENOMEM; 378 memcpy(buf, xbuf, qlen); 379 return qlen; 380 } 381} 382 383 384/* decode note event */ 385static void note_decode(struct snd_seq_event *ev, unsigned char *buf) 386{ 387 buf[0] = ev->data.note.note & 0x7f; 388 buf[1] = ev->data.note.velocity & 0x7f; 389} 390 391/* decode one parameter controls */ 392static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf) 393{ 394 buf[0] = ev->data.control.value & 0x7f; 395} 396 397/* decode pitch wheel change */ 398static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf) 399{ 400 int value = ev->data.control.value + 8192; 401 buf[0] = value & 0x7f; 402 buf[1] = (value >> 7) & 0x7f; 403} 404 405/* decode midi control change */ 406static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf) 407{ 408 buf[0] = ev->data.control.param & 0x7f; 409 buf[1] = ev->data.control.value & 0x7f; 410} 411 412/* decode song position */ 413static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf) 414{ 415 buf[0] = ev->data.control.value & 0x7f; 416 buf[1] = (ev->data.control.value >> 7) & 0x7f; 417} 418 419/* decode 14bit control */ 420static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, 421 int count, struct snd_seq_event *ev) 422{ 423 unsigned char cmd; 424 int idx = 0; 425 426 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 427 if (ev->data.control.param < 0x20) { 428 if (count < 4) 429 return -ENOMEM; 430 if (dev->nostat && count < 6) 431 return -ENOMEM; 432 if (cmd != dev->lastcmd || dev->nostat) { 433 if (count < 5) 434 return -ENOMEM; 435 buf[idx++] = dev->lastcmd = cmd; 436 } 437 buf[idx++] = ev->data.control.param; 438 buf[idx++] = (ev->data.control.value >> 7) & 0x7f; 439 if (dev->nostat) 440 buf[idx++] = cmd; 441 buf[idx++] = ev->data.control.param + 0x20; 442 buf[idx++] = ev->data.control.value & 0x7f; 443 } else { 444 if (count < 2) 445 return -ENOMEM; 446 if (cmd != dev->lastcmd || dev->nostat) { 447 if (count < 3) 448 return -ENOMEM; 449 buf[idx++] = dev->lastcmd = cmd; 450 } 451 buf[idx++] = ev->data.control.param & 0x7f; 452 buf[idx++] = ev->data.control.value & 0x7f; 453 } 454 return idx; 455} 456 457/* decode reg/nonreg param */ 458static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, 459 int count, struct snd_seq_event *ev) 460{ 461 unsigned char cmd; 462 char *cbytes; 463 static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB, 464 MIDI_CTL_NONREG_PARM_NUM_LSB, 465 MIDI_CTL_MSB_DATA_ENTRY, 466 MIDI_CTL_LSB_DATA_ENTRY }; 467 static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB, 468 MIDI_CTL_REGIST_PARM_NUM_LSB, 469 MIDI_CTL_MSB_DATA_ENTRY, 470 MIDI_CTL_LSB_DATA_ENTRY }; 471 unsigned char bytes[4]; 472 int idx = 0, i; 473 474 if (count < 8) 475 return -ENOMEM; 476 if (dev->nostat && count < 12) 477 return -ENOMEM; 478 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 479 bytes[0] = (ev->data.control.param & 0x3f80) >> 7; 480 bytes[1] = ev->data.control.param & 0x007f; 481 bytes[2] = (ev->data.control.value & 0x3f80) >> 7; 482 bytes[3] = ev->data.control.value & 0x007f; 483 if (cmd != dev->lastcmd && !dev->nostat) { 484 if (count < 9) 485 return -ENOMEM; 486 buf[idx++] = dev->lastcmd = cmd; 487 } 488 cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn; 489 for (i = 0; i < 4; i++) { 490 if (dev->nostat) 491 buf[idx++] = dev->lastcmd = cmd; 492 buf[idx++] = cbytes[i]; 493 buf[idx++] = bytes[i]; 494 } 495 return idx; 496} 497 498/* 499 * exports 500 */ 501 502EXPORT_SYMBOL(snd_midi_event_new); 503EXPORT_SYMBOL(snd_midi_event_free); 504EXPORT_SYMBOL(snd_midi_event_reset_encode); 505EXPORT_SYMBOL(snd_midi_event_reset_decode); 506EXPORT_SYMBOL(snd_midi_event_no_status); 507EXPORT_SYMBOL(snd_midi_event_encode); 508EXPORT_SYMBOL(snd_midi_event_encode_byte); 509EXPORT_SYMBOL(snd_midi_event_decode); 510 511static int __init alsa_seq_midi_event_init(void) 512{ 513 return 0; 514} 515 516static void __exit alsa_seq_midi_event_exit(void) 517{ 518} 519 520module_init(alsa_seq_midi_event_init) 521module_exit(alsa_seq_midi_event_exit) 522