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 void snd_midi_event_no_status(struct snd_midi_event *dev, int on) 179 { 180 dev->nostat = on ? 1 : 0; 181 } 182 EXPORT_SYMBOL(snd_midi_event_no_status); 183 184 /* 185 * read one byte and encode to sequencer event: 186 * return true if MIDI bytes are encoded to an event 187 * false data is not finished 188 */ 189 bool snd_midi_event_encode_byte(struct snd_midi_event *dev, unsigned char c, 190 struct snd_seq_event *ev) 191 { 192 bool rc = false; 193 unsigned long flags; 194 195 if (c >= MIDI_CMD_COMMON_CLOCK) { 196 /* real-time event */ 197 ev->type = status_event[ST_SPECIAL + c - 0xf0].event; 198 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 199 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 200 return ev->type != SNDRV_SEQ_EVENT_NONE; 201 } 202 203 spin_lock_irqsave(&dev->lock, flags); 204 if ((c & 0x80) && 205 (c != MIDI_CMD_COMMON_SYSEX_END || dev->type != ST_SYSEX)) { 206 /* new command */ 207 dev->buf[0] = c; 208 if ((c & 0xf0) == 0xf0) /* system messages */ 209 dev->type = (c & 0x0f) + ST_SPECIAL; 210 else 211 dev->type = (c >> 4) & 0x07; 212 dev->read = 1; 213 dev->qlen = status_event[dev->type].qlen; 214 } else { 215 if (dev->qlen > 0) { 216 /* rest of command */ 217 dev->buf[dev->read++] = c; 218 if (dev->type != ST_SYSEX) 219 dev->qlen--; 220 } else { 221 /* running status */ 222 dev->buf[1] = c; 223 dev->qlen = status_event[dev->type].qlen - 1; 224 dev->read = 2; 225 } 226 } 227 if (dev->qlen == 0) { 228 ev->type = status_event[dev->type].event; 229 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 230 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; 231 if (status_event[dev->type].encode) /* set data values */ 232 status_event[dev->type].encode(dev, ev); 233 if (dev->type >= ST_SPECIAL) 234 dev->type = ST_INVALID; 235 rc = true; 236 } else if (dev->type == ST_SYSEX) { 237 if (c == MIDI_CMD_COMMON_SYSEX_END || 238 dev->read >= dev->bufsize) { 239 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; 240 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE; 241 ev->type = SNDRV_SEQ_EVENT_SYSEX; 242 ev->data.ext.len = dev->read; 243 ev->data.ext.ptr = dev->buf; 244 if (c != MIDI_CMD_COMMON_SYSEX_END) 245 dev->read = 0; /* continue to parse */ 246 else 247 reset_encode(dev); /* all parsed */ 248 rc = true; 249 } 250 } 251 252 spin_unlock_irqrestore(&dev->lock, flags); 253 return rc; 254 } 255 EXPORT_SYMBOL(snd_midi_event_encode_byte); 256 257 /* encode note event */ 258 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 259 { 260 ev->data.note.channel = dev->buf[0] & 0x0f; 261 ev->data.note.note = dev->buf[1]; 262 ev->data.note.velocity = dev->buf[2]; 263 } 264 265 /* encode one parameter controls */ 266 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 267 { 268 ev->data.control.channel = dev->buf[0] & 0x0f; 269 ev->data.control.value = dev->buf[1]; 270 } 271 272 /* encode pitch wheel change */ 273 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 274 { 275 ev->data.control.channel = dev->buf[0] & 0x0f; 276 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192; 277 } 278 279 /* encode midi control change */ 280 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 281 { 282 ev->data.control.channel = dev->buf[0] & 0x0f; 283 ev->data.control.param = dev->buf[1]; 284 ev->data.control.value = dev->buf[2]; 285 } 286 287 /* encode one parameter value*/ 288 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 289 { 290 ev->data.control.value = dev->buf[1]; 291 } 292 293 /* encode song position */ 294 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev) 295 { 296 ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1]; 297 } 298 299 /* 300 * decode from a sequencer event to midi bytes 301 * return the size of decoded midi events 302 */ 303 long snd_midi_event_decode(struct snd_midi_event *dev, unsigned char *buf, long count, 304 struct snd_seq_event *ev) 305 { 306 unsigned int cmd, type; 307 308 if (ev->type == SNDRV_SEQ_EVENT_NONE) 309 return -ENOENT; 310 311 for (type = 0; type < ARRAY_SIZE(status_event); type++) { 312 if (ev->type == status_event[type].event) 313 goto __found; 314 } 315 for (type = 0; type < ARRAY_SIZE(extra_event); type++) { 316 if (ev->type == extra_event[type].event) 317 return extra_event[type].decode(dev, buf, count, ev); 318 } 319 return -ENOENT; 320 321 __found: 322 if (type >= ST_SPECIAL) 323 cmd = 0xf0 + (type - ST_SPECIAL); 324 else 325 /* data.note.channel and data.control.channel is identical */ 326 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f); 327 328 329 if (cmd == MIDI_CMD_COMMON_SYSEX) { 330 snd_midi_event_reset_decode(dev); 331 return snd_seq_expand_var_event(ev, count, buf, 1, 0); 332 } else { 333 int qlen; 334 unsigned char xbuf[4]; 335 unsigned long flags; 336 337 spin_lock_irqsave(&dev->lock, flags); 338 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) { 339 dev->lastcmd = cmd; 340 spin_unlock_irqrestore(&dev->lock, flags); 341 xbuf[0] = cmd; 342 if (status_event[type].decode) 343 status_event[type].decode(ev, xbuf + 1); 344 qlen = status_event[type].qlen + 1; 345 } else { 346 spin_unlock_irqrestore(&dev->lock, flags); 347 if (status_event[type].decode) 348 status_event[type].decode(ev, xbuf + 0); 349 qlen = status_event[type].qlen; 350 } 351 if (count < qlen) 352 return -ENOMEM; 353 memcpy(buf, xbuf, qlen); 354 return qlen; 355 } 356 } 357 EXPORT_SYMBOL(snd_midi_event_decode); 358 359 360 /* decode note event */ 361 static void note_decode(struct snd_seq_event *ev, unsigned char *buf) 362 { 363 buf[0] = ev->data.note.note & 0x7f; 364 buf[1] = ev->data.note.velocity & 0x7f; 365 } 366 367 /* decode one parameter controls */ 368 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf) 369 { 370 buf[0] = ev->data.control.value & 0x7f; 371 } 372 373 /* decode pitch wheel change */ 374 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf) 375 { 376 int value = ev->data.control.value + 8192; 377 buf[0] = value & 0x7f; 378 buf[1] = (value >> 7) & 0x7f; 379 } 380 381 /* decode midi control change */ 382 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf) 383 { 384 buf[0] = ev->data.control.param & 0x7f; 385 buf[1] = ev->data.control.value & 0x7f; 386 } 387 388 /* decode song position */ 389 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf) 390 { 391 buf[0] = ev->data.control.value & 0x7f; 392 buf[1] = (ev->data.control.value >> 7) & 0x7f; 393 } 394 395 /* decode 14bit control */ 396 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, 397 int count, struct snd_seq_event *ev) 398 { 399 unsigned char cmd; 400 int idx = 0; 401 402 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 403 if (ev->data.control.param < 0x20) { 404 if (count < 4) 405 return -ENOMEM; 406 if (dev->nostat && count < 6) 407 return -ENOMEM; 408 if (cmd != dev->lastcmd || dev->nostat) { 409 if (count < 5) 410 return -ENOMEM; 411 buf[idx++] = dev->lastcmd = cmd; 412 } 413 buf[idx++] = ev->data.control.param; 414 buf[idx++] = (ev->data.control.value >> 7) & 0x7f; 415 if (dev->nostat) 416 buf[idx++] = cmd; 417 buf[idx++] = ev->data.control.param + 0x20; 418 buf[idx++] = ev->data.control.value & 0x7f; 419 } else { 420 if (count < 2) 421 return -ENOMEM; 422 if (cmd != dev->lastcmd || dev->nostat) { 423 if (count < 3) 424 return -ENOMEM; 425 buf[idx++] = dev->lastcmd = cmd; 426 } 427 buf[idx++] = ev->data.control.param & 0x7f; 428 buf[idx++] = ev->data.control.value & 0x7f; 429 } 430 return idx; 431 } 432 433 /* decode reg/nonreg param */ 434 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, 435 int count, struct snd_seq_event *ev) 436 { 437 unsigned char cmd; 438 char *cbytes; 439 static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB, 440 MIDI_CTL_NONREG_PARM_NUM_LSB, 441 MIDI_CTL_MSB_DATA_ENTRY, 442 MIDI_CTL_LSB_DATA_ENTRY }; 443 static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB, 444 MIDI_CTL_REGIST_PARM_NUM_LSB, 445 MIDI_CTL_MSB_DATA_ENTRY, 446 MIDI_CTL_LSB_DATA_ENTRY }; 447 unsigned char bytes[4]; 448 int idx = 0, i; 449 450 if (count < 8) 451 return -ENOMEM; 452 if (dev->nostat && count < 12) 453 return -ENOMEM; 454 cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f); 455 bytes[0] = (ev->data.control.param & 0x3f80) >> 7; 456 bytes[1] = ev->data.control.param & 0x007f; 457 bytes[2] = (ev->data.control.value & 0x3f80) >> 7; 458 bytes[3] = ev->data.control.value & 0x007f; 459 if (cmd != dev->lastcmd && !dev->nostat) { 460 if (count < 9) 461 return -ENOMEM; 462 buf[idx++] = dev->lastcmd = cmd; 463 } 464 cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn; 465 for (i = 0; i < 4; i++) { 466 if (dev->nostat) 467 buf[idx++] = dev->lastcmd = cmd; 468 buf[idx++] = cbytes[i]; 469 buf[idx++] = bytes[i]; 470 } 471 return idx; 472 } 473