1 /* 2 * Virtual Raw MIDI client on Sequencer 3 * 4 * Copyright (c) 2000 by 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 23 /* 24 * Virtual Raw MIDI client 25 * 26 * The virtual rawmidi client is a sequencer client which associate 27 * a rawmidi device file. The created rawmidi device file can be 28 * accessed as a normal raw midi, but its MIDI source and destination 29 * are arbitrary. For example, a user-client software synth connected 30 * to this port can be used as a normal midi device as well. 31 * 32 * The virtual rawmidi device accepts also multiple opens. Each file 33 * has its own input buffer, so that no conflict would occur. The drain 34 * of input/output buffer acts only to the local buffer. 35 * 36 */ 37 38 #include <sound/driver.h> 39 #include <linux/init.h> 40 #include <linux/wait.h> 41 #include <linux/sched.h> 42 #include <linux/slab.h> 43 #include <sound/core.h> 44 #include <sound/rawmidi.h> 45 #include <sound/info.h> 46 #include <sound/control.h> 47 #include <sound/minors.h> 48 #include <sound/seq_kernel.h> 49 #include <sound/seq_midi_event.h> 50 #include <sound/seq_virmidi.h> 51 52 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>"); 53 MODULE_DESCRIPTION("Virtual Raw MIDI client on Sequencer"); 54 MODULE_LICENSE("GPL"); 55 56 /* 57 * initialize an event record 58 */ 59 static void snd_virmidi_init_event(snd_virmidi_t *vmidi, snd_seq_event_t *ev) 60 { 61 memset(ev, 0, sizeof(*ev)); 62 ev->source.port = vmidi->port; 63 switch (vmidi->seq_mode) { 64 case SNDRV_VIRMIDI_SEQ_DISPATCH: 65 ev->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS; 66 break; 67 case SNDRV_VIRMIDI_SEQ_ATTACH: 68 /* FIXME: source and destination are same - not good.. */ 69 ev->dest.client = vmidi->client; 70 ev->dest.port = vmidi->port; 71 break; 72 } 73 ev->type = SNDRV_SEQ_EVENT_NONE; 74 } 75 76 /* 77 * decode input event and put to read buffer of each opened file 78 */ 79 static int snd_virmidi_dev_receive_event(snd_virmidi_dev_t *rdev, snd_seq_event_t *ev) 80 { 81 snd_virmidi_t *vmidi; 82 struct list_head *list; 83 unsigned char msg[4]; 84 int len; 85 86 read_lock(&rdev->filelist_lock); 87 list_for_each(list, &rdev->filelist) { 88 vmidi = list_entry(list, snd_virmidi_t, list); 89 if (!vmidi->trigger) 90 continue; 91 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { 92 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) 93 continue; 94 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream); 95 } else { 96 len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev); 97 if (len > 0) 98 snd_rawmidi_receive(vmidi->substream, msg, len); 99 } 100 } 101 read_unlock(&rdev->filelist_lock); 102 103 return 0; 104 } 105 106 /* 107 * receive an event from the remote virmidi port 108 * 109 * for rawmidi inputs, you can call this function from the event 110 * handler of a remote port which is attached to the virmidi via 111 * SNDRV_VIRMIDI_SEQ_ATTACH. 112 */ 113 /* exported */ 114 int snd_virmidi_receive(snd_rawmidi_t *rmidi, snd_seq_event_t *ev) 115 { 116 snd_virmidi_dev_t *rdev; 117 118 rdev = rmidi->private_data; 119 return snd_virmidi_dev_receive_event(rdev, ev); 120 } 121 122 /* 123 * event handler of virmidi port 124 */ 125 static int snd_virmidi_event_input(snd_seq_event_t *ev, int direct, 126 void *private_data, int atomic, int hop) 127 { 128 snd_virmidi_dev_t *rdev; 129 130 rdev = private_data; 131 if (!(rdev->flags & SNDRV_VIRMIDI_USE)) 132 return 0; /* ignored */ 133 return snd_virmidi_dev_receive_event(rdev, ev); 134 } 135 136 /* 137 * trigger rawmidi stream for input 138 */ 139 static void snd_virmidi_input_trigger(snd_rawmidi_substream_t * substream, int up) 140 { 141 snd_virmidi_t *vmidi = substream->runtime->private_data; 142 143 if (up) { 144 vmidi->trigger = 1; 145 } else { 146 vmidi->trigger = 0; 147 } 148 } 149 150 /* 151 * trigger rawmidi stream for output 152 */ 153 static void snd_virmidi_output_trigger(snd_rawmidi_substream_t * substream, int up) 154 { 155 snd_virmidi_t *vmidi = substream->runtime->private_data; 156 int count, res; 157 unsigned char buf[32], *pbuf; 158 159 if (up) { 160 vmidi->trigger = 1; 161 if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH && 162 !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) { 163 snd_rawmidi_transmit_ack(substream, substream->runtime->buffer_size - substream->runtime->avail); 164 return; /* ignored */ 165 } 166 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) { 167 if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, 0, 0) < 0) 168 return; 169 vmidi->event.type = SNDRV_SEQ_EVENT_NONE; 170 } 171 while (1) { 172 count = snd_rawmidi_transmit_peek(substream, buf, sizeof(buf)); 173 if (count <= 0) 174 break; 175 pbuf = buf; 176 while (count > 0) { 177 res = snd_midi_event_encode(vmidi->parser, pbuf, count, &vmidi->event); 178 if (res < 0) { 179 snd_midi_event_reset_encode(vmidi->parser); 180 continue; 181 } 182 snd_rawmidi_transmit_ack(substream, res); 183 pbuf += res; 184 count -= res; 185 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) { 186 if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, 0, 0) < 0) 187 return; 188 vmidi->event.type = SNDRV_SEQ_EVENT_NONE; 189 } 190 } 191 } 192 } else { 193 vmidi->trigger = 0; 194 } 195 } 196 197 /* 198 * open rawmidi handle for input 199 */ 200 static int snd_virmidi_input_open(snd_rawmidi_substream_t * substream) 201 { 202 snd_virmidi_dev_t *rdev = substream->rmidi->private_data; 203 snd_rawmidi_runtime_t *runtime = substream->runtime; 204 snd_virmidi_t *vmidi; 205 unsigned long flags; 206 207 vmidi = kcalloc(1, sizeof(*vmidi), GFP_KERNEL); 208 if (vmidi == NULL) 209 return -ENOMEM; 210 vmidi->substream = substream; 211 if (snd_midi_event_new(0, &vmidi->parser) < 0) { 212 kfree(vmidi); 213 return -ENOMEM; 214 } 215 vmidi->seq_mode = rdev->seq_mode; 216 vmidi->client = rdev->client; 217 vmidi->port = rdev->port; 218 runtime->private_data = vmidi; 219 write_lock_irqsave(&rdev->filelist_lock, flags); 220 list_add_tail(&vmidi->list, &rdev->filelist); 221 write_unlock_irqrestore(&rdev->filelist_lock, flags); 222 vmidi->rdev = rdev; 223 return 0; 224 } 225 226 /* 227 * open rawmidi handle for output 228 */ 229 static int snd_virmidi_output_open(snd_rawmidi_substream_t * substream) 230 { 231 snd_virmidi_dev_t *rdev = substream->rmidi->private_data; 232 snd_rawmidi_runtime_t *runtime = substream->runtime; 233 snd_virmidi_t *vmidi; 234 235 vmidi = kcalloc(1, sizeof(*vmidi), GFP_KERNEL); 236 if (vmidi == NULL) 237 return -ENOMEM; 238 vmidi->substream = substream; 239 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) { 240 kfree(vmidi); 241 return -ENOMEM; 242 } 243 vmidi->seq_mode = rdev->seq_mode; 244 vmidi->client = rdev->client; 245 vmidi->port = rdev->port; 246 snd_virmidi_init_event(vmidi, &vmidi->event); 247 vmidi->rdev = rdev; 248 runtime->private_data = vmidi; 249 return 0; 250 } 251 252 /* 253 * close rawmidi handle for input 254 */ 255 static int snd_virmidi_input_close(snd_rawmidi_substream_t * substream) 256 { 257 snd_virmidi_t *vmidi = substream->runtime->private_data; 258 snd_midi_event_free(vmidi->parser); 259 list_del(&vmidi->list); 260 substream->runtime->private_data = NULL; 261 kfree(vmidi); 262 return 0; 263 } 264 265 /* 266 * close rawmidi handle for output 267 */ 268 static int snd_virmidi_output_close(snd_rawmidi_substream_t * substream) 269 { 270 snd_virmidi_t *vmidi = substream->runtime->private_data; 271 snd_midi_event_free(vmidi->parser); 272 substream->runtime->private_data = NULL; 273 kfree(vmidi); 274 return 0; 275 } 276 277 /* 278 * subscribe callback - allow output to rawmidi device 279 */ 280 static int snd_virmidi_subscribe(void *private_data, snd_seq_port_subscribe_t *info) 281 { 282 snd_virmidi_dev_t *rdev; 283 284 rdev = private_data; 285 if (!try_module_get(rdev->card->module)) 286 return -EFAULT; 287 rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE; 288 return 0; 289 } 290 291 /* 292 * unsubscribe callback - disallow output to rawmidi device 293 */ 294 static int snd_virmidi_unsubscribe(void *private_data, snd_seq_port_subscribe_t *info) 295 { 296 snd_virmidi_dev_t *rdev; 297 298 rdev = private_data; 299 rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE; 300 module_put(rdev->card->module); 301 return 0; 302 } 303 304 305 /* 306 * use callback - allow input to rawmidi device 307 */ 308 static int snd_virmidi_use(void *private_data, snd_seq_port_subscribe_t *info) 309 { 310 snd_virmidi_dev_t *rdev; 311 312 rdev = private_data; 313 if (!try_module_get(rdev->card->module)) 314 return -EFAULT; 315 rdev->flags |= SNDRV_VIRMIDI_USE; 316 return 0; 317 } 318 319 /* 320 * unuse callback - disallow input to rawmidi device 321 */ 322 static int snd_virmidi_unuse(void *private_data, snd_seq_port_subscribe_t *info) 323 { 324 snd_virmidi_dev_t *rdev; 325 326 rdev = private_data; 327 rdev->flags &= ~SNDRV_VIRMIDI_USE; 328 module_put(rdev->card->module); 329 return 0; 330 } 331 332 333 /* 334 * Register functions 335 */ 336 337 static snd_rawmidi_ops_t snd_virmidi_input_ops = { 338 .open = snd_virmidi_input_open, 339 .close = snd_virmidi_input_close, 340 .trigger = snd_virmidi_input_trigger, 341 }; 342 343 static snd_rawmidi_ops_t snd_virmidi_output_ops = { 344 .open = snd_virmidi_output_open, 345 .close = snd_virmidi_output_close, 346 .trigger = snd_virmidi_output_trigger, 347 }; 348 349 /* 350 * create a sequencer client and a port 351 */ 352 static int snd_virmidi_dev_attach_seq(snd_virmidi_dev_t *rdev) 353 { 354 int client; 355 snd_seq_client_callback_t callbacks; 356 snd_seq_port_callback_t pcallbacks; 357 snd_seq_client_info_t *info; 358 snd_seq_port_info_t *pinfo; 359 int err; 360 361 if (rdev->client >= 0) 362 return 0; 363 364 info = kmalloc(sizeof(*info), GFP_KERNEL); 365 pinfo = kmalloc(sizeof(*pinfo), GFP_KERNEL); 366 if (! info || ! pinfo) { 367 err = -ENOMEM; 368 goto __error; 369 } 370 371 memset(&callbacks, 0, sizeof(callbacks)); 372 callbacks.private_data = rdev; 373 callbacks.allow_input = 1; 374 callbacks.allow_output = 1; 375 client = snd_seq_create_kernel_client(rdev->card, rdev->device, &callbacks); 376 if (client < 0) { 377 err = client; 378 goto __error; 379 } 380 rdev->client = client; 381 382 /* set client name */ 383 memset(info, 0, sizeof(*info)); 384 info->client = client; 385 info->type = KERNEL_CLIENT; 386 sprintf(info->name, "%s %d-%d", rdev->rmidi->name, rdev->card->number, rdev->device); 387 snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, &info); 388 389 /* create a port */ 390 memset(pinfo, 0, sizeof(*pinfo)); 391 pinfo->addr.client = client; 392 sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device); 393 /* set all capabilities */ 394 pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 395 pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 396 pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 397 pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC; 398 pinfo->midi_channels = 16; 399 memset(&pcallbacks, 0, sizeof(pcallbacks)); 400 pcallbacks.owner = THIS_MODULE; 401 pcallbacks.private_data = rdev; 402 pcallbacks.subscribe = snd_virmidi_subscribe; 403 pcallbacks.unsubscribe = snd_virmidi_unsubscribe; 404 pcallbacks.use = snd_virmidi_use; 405 pcallbacks.unuse = snd_virmidi_unuse; 406 pcallbacks.event_input = snd_virmidi_event_input; 407 pinfo->kernel = &pcallbacks; 408 err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, &pinfo); 409 if (err < 0) { 410 snd_seq_delete_kernel_client(client); 411 rdev->client = -1; 412 goto __error; 413 } 414 415 rdev->port = pinfo->addr.port; 416 err = 0; /* success */ 417 418 __error: 419 kfree(info); 420 kfree(pinfo); 421 return err; 422 } 423 424 425 /* 426 * release the sequencer client 427 */ 428 static void snd_virmidi_dev_detach_seq(snd_virmidi_dev_t *rdev) 429 { 430 if (rdev->client >= 0) { 431 snd_seq_delete_kernel_client(rdev->client); 432 rdev->client = -1; 433 } 434 } 435 436 /* 437 * register the device 438 */ 439 static int snd_virmidi_dev_register(snd_rawmidi_t *rmidi) 440 { 441 snd_virmidi_dev_t *rdev = rmidi->private_data; 442 int err; 443 444 switch (rdev->seq_mode) { 445 case SNDRV_VIRMIDI_SEQ_DISPATCH: 446 err = snd_virmidi_dev_attach_seq(rdev); 447 if (err < 0) 448 return err; 449 break; 450 case SNDRV_VIRMIDI_SEQ_ATTACH: 451 if (rdev->client == 0) 452 return -EINVAL; 453 /* should check presence of port more strictly.. */ 454 break; 455 default: 456 snd_printk(KERN_ERR "seq_mode is not set: %d\n", rdev->seq_mode); 457 return -EINVAL; 458 } 459 return 0; 460 } 461 462 463 /* 464 * unregister the device 465 */ 466 static int snd_virmidi_dev_unregister(snd_rawmidi_t *rmidi) 467 { 468 snd_virmidi_dev_t *rdev = rmidi->private_data; 469 470 if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH) 471 snd_virmidi_dev_detach_seq(rdev); 472 return 0; 473 } 474 475 /* 476 * 477 */ 478 static snd_rawmidi_global_ops_t snd_virmidi_global_ops = { 479 .dev_register = snd_virmidi_dev_register, 480 .dev_unregister = snd_virmidi_dev_unregister, 481 }; 482 483 /* 484 * free device 485 */ 486 static void snd_virmidi_free(snd_rawmidi_t *rmidi) 487 { 488 snd_virmidi_dev_t *rdev = rmidi->private_data; 489 kfree(rdev); 490 } 491 492 /* 493 * create a new device 494 * 495 */ 496 /* exported */ 497 int snd_virmidi_new(snd_card_t *card, int device, snd_rawmidi_t **rrmidi) 498 { 499 snd_rawmidi_t *rmidi; 500 snd_virmidi_dev_t *rdev; 501 int err; 502 503 *rrmidi = NULL; 504 if ((err = snd_rawmidi_new(card, "VirMidi", device, 505 16, /* may be configurable */ 506 16, /* may be configurable */ 507 &rmidi)) < 0) 508 return err; 509 strcpy(rmidi->name, rmidi->id); 510 rdev = kcalloc(1, sizeof(*rdev), GFP_KERNEL); 511 if (rdev == NULL) { 512 snd_device_free(card, rmidi); 513 return -ENOMEM; 514 } 515 rdev->card = card; 516 rdev->rmidi = rmidi; 517 rdev->device = device; 518 rdev->client = -1; 519 rwlock_init(&rdev->filelist_lock); 520 INIT_LIST_HEAD(&rdev->filelist); 521 rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH; 522 rmidi->private_data = rdev; 523 rmidi->private_free = snd_virmidi_free; 524 rmidi->ops = &snd_virmidi_global_ops; 525 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops); 526 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops); 527 rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT | 528 SNDRV_RAWMIDI_INFO_OUTPUT | 529 SNDRV_RAWMIDI_INFO_DUPLEX; 530 *rrmidi = rmidi; 531 return 0; 532 } 533 534 /* 535 * ENTRY functions 536 */ 537 538 static int __init alsa_virmidi_init(void) 539 { 540 return 0; 541 } 542 543 static void __exit alsa_virmidi_exit(void) 544 { 545 } 546 547 module_init(alsa_virmidi_init) 548 module_exit(alsa_virmidi_exit) 549 550 EXPORT_SYMBOL(snd_virmidi_new); 551 EXPORT_SYMBOL(snd_virmidi_receive); 552