1 /* 2 * Generic MIDI synth driver for ALSA sequencer 3 * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl> 4 * Jaroslav Kysela <perex@perex.cz> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 */ 21 22 /* 23 Possible options for midisynth module: 24 - automatic opening of midi ports on first received event or subscription 25 (close will be performed when client leaves) 26 */ 27 28 29 #include <linux/init.h> 30 #include <linux/slab.h> 31 #include <linux/errno.h> 32 #include <linux/string.h> 33 #include <linux/moduleparam.h> 34 #include <linux/mutex.h> 35 #include <sound/core.h> 36 #include <sound/rawmidi.h> 37 #include <sound/seq_kernel.h> 38 #include <sound/seq_device.h> 39 #include <sound/seq_midi_event.h> 40 #include <sound/initval.h> 41 42 MODULE_AUTHOR("Frank van de Pol <fvdpol@coil.demon.nl>, Jaroslav Kysela <perex@perex.cz>"); 43 MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI synth."); 44 MODULE_LICENSE("GPL"); 45 static int output_buffer_size = PAGE_SIZE; 46 module_param(output_buffer_size, int, 0644); 47 MODULE_PARM_DESC(output_buffer_size, "Output buffer size in bytes."); 48 static int input_buffer_size = PAGE_SIZE; 49 module_param(input_buffer_size, int, 0644); 50 MODULE_PARM_DESC(input_buffer_size, "Input buffer size in bytes."); 51 52 /* data for this midi synth driver */ 53 struct seq_midisynth { 54 struct snd_card *card; 55 int device; 56 int subdevice; 57 struct snd_rawmidi_file input_rfile; 58 struct snd_rawmidi_file output_rfile; 59 int seq_client; 60 int seq_port; 61 struct snd_midi_event *parser; 62 }; 63 64 struct seq_midisynth_client { 65 int seq_client; 66 int num_ports; 67 int ports_per_device[SNDRV_RAWMIDI_DEVICES]; 68 struct seq_midisynth *ports[SNDRV_RAWMIDI_DEVICES]; 69 }; 70 71 static struct seq_midisynth_client *synths[SNDRV_CARDS]; 72 static DEFINE_MUTEX(register_mutex); 73 74 /* handle rawmidi input event (MIDI v1.0 stream) */ 75 static void snd_midi_input_event(struct snd_rawmidi_substream *substream) 76 { 77 struct snd_rawmidi_runtime *runtime; 78 struct seq_midisynth *msynth; 79 struct snd_seq_event ev; 80 char buf[16], *pbuf; 81 long res, count; 82 83 if (substream == NULL) 84 return; 85 runtime = substream->runtime; 86 msynth = runtime->private_data; 87 if (msynth == NULL) 88 return; 89 memset(&ev, 0, sizeof(ev)); 90 while (runtime->avail > 0) { 91 res = snd_rawmidi_kernel_read(substream, buf, sizeof(buf)); 92 if (res <= 0) 93 continue; 94 if (msynth->parser == NULL) 95 continue; 96 pbuf = buf; 97 while (res > 0) { 98 count = snd_midi_event_encode(msynth->parser, pbuf, res, &ev); 99 if (count < 0) 100 break; 101 pbuf += count; 102 res -= count; 103 if (ev.type != SNDRV_SEQ_EVENT_NONE) { 104 ev.source.port = msynth->seq_port; 105 ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS; 106 snd_seq_kernel_client_dispatch(msynth->seq_client, &ev, 1, 0); 107 /* clear event and reset header */ 108 memset(&ev, 0, sizeof(ev)); 109 } 110 } 111 } 112 } 113 114 static int dump_midi(struct snd_rawmidi_substream *substream, const char *buf, int count) 115 { 116 struct snd_rawmidi_runtime *runtime; 117 int tmp; 118 119 if (snd_BUG_ON(!substream || !buf)) 120 return -EINVAL; 121 runtime = substream->runtime; 122 if ((tmp = runtime->avail) < count) { 123 snd_printd("warning, output event was lost (count = %i, available = %i)\n", count, tmp); 124 return -ENOMEM; 125 } 126 if (snd_rawmidi_kernel_write(substream, buf, count) < count) 127 return -EINVAL; 128 return 0; 129 } 130 131 static int event_process_midi(struct snd_seq_event *ev, int direct, 132 void *private_data, int atomic, int hop) 133 { 134 struct seq_midisynth *msynth = private_data; 135 unsigned char msg[10]; /* buffer for constructing midi messages */ 136 struct snd_rawmidi_substream *substream; 137 int len; 138 139 if (snd_BUG_ON(!msynth)) 140 return -EINVAL; 141 substream = msynth->output_rfile.output; 142 if (substream == NULL) 143 return -ENODEV; 144 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */ 145 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) { 146 /* invalid event */ 147 snd_printd("seq_midi: invalid sysex event flags = 0x%x\n", ev->flags); 148 return 0; 149 } 150 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream); 151 snd_midi_event_reset_decode(msynth->parser); 152 } else { 153 if (msynth->parser == NULL) 154 return -EIO; 155 len = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev); 156 if (len < 0) 157 return 0; 158 if (dump_midi(substream, msg, len) < 0) 159 snd_midi_event_reset_decode(msynth->parser); 160 } 161 return 0; 162 } 163 164 165 static int snd_seq_midisynth_new(struct seq_midisynth *msynth, 166 struct snd_card *card, 167 int device, 168 int subdevice) 169 { 170 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0) 171 return -ENOMEM; 172 msynth->card = card; 173 msynth->device = device; 174 msynth->subdevice = subdevice; 175 return 0; 176 } 177 178 /* open associated midi device for input */ 179 static int midisynth_subscribe(void *private_data, struct snd_seq_port_subscribe *info) 180 { 181 int err; 182 struct seq_midisynth *msynth = private_data; 183 struct snd_rawmidi_runtime *runtime; 184 struct snd_rawmidi_params params; 185 186 /* open midi port */ 187 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device, 188 msynth->subdevice, 189 SNDRV_RAWMIDI_LFLG_INPUT, 190 &msynth->input_rfile)) < 0) { 191 snd_printd("midi input open failed!!!\n"); 192 return err; 193 } 194 runtime = msynth->input_rfile.input->runtime; 195 memset(¶ms, 0, sizeof(params)); 196 params.avail_min = 1; 197 params.buffer_size = input_buffer_size; 198 if ((err = snd_rawmidi_input_params(msynth->input_rfile.input, ¶ms)) < 0) { 199 snd_rawmidi_kernel_release(&msynth->input_rfile); 200 return err; 201 } 202 snd_midi_event_reset_encode(msynth->parser); 203 runtime->event = snd_midi_input_event; 204 runtime->private_data = msynth; 205 snd_rawmidi_kernel_read(msynth->input_rfile.input, NULL, 0); 206 return 0; 207 } 208 209 /* close associated midi device for input */ 210 static int midisynth_unsubscribe(void *private_data, struct snd_seq_port_subscribe *info) 211 { 212 int err; 213 struct seq_midisynth *msynth = private_data; 214 215 if (snd_BUG_ON(!msynth->input_rfile.input)) 216 return -EINVAL; 217 err = snd_rawmidi_kernel_release(&msynth->input_rfile); 218 return err; 219 } 220 221 /* open associated midi device for output */ 222 static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info) 223 { 224 int err; 225 struct seq_midisynth *msynth = private_data; 226 struct snd_rawmidi_params params; 227 228 /* open midi port */ 229 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device, 230 msynth->subdevice, 231 SNDRV_RAWMIDI_LFLG_OUTPUT, 232 &msynth->output_rfile)) < 0) { 233 snd_printd("midi output open failed!!!\n"); 234 return err; 235 } 236 memset(¶ms, 0, sizeof(params)); 237 params.avail_min = 1; 238 params.buffer_size = output_buffer_size; 239 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) { 240 snd_rawmidi_kernel_release(&msynth->output_rfile); 241 return err; 242 } 243 snd_midi_event_reset_decode(msynth->parser); 244 return 0; 245 } 246 247 /* close associated midi device for output */ 248 static int midisynth_unuse(void *private_data, struct snd_seq_port_subscribe *info) 249 { 250 struct seq_midisynth *msynth = private_data; 251 unsigned char buf = 0xff; /* MIDI reset */ 252 253 if (snd_BUG_ON(!msynth->output_rfile.output)) 254 return -EINVAL; 255 /* sending single MIDI reset message to shut the device up */ 256 snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1); 257 snd_rawmidi_drain_output(msynth->output_rfile.output); 258 return snd_rawmidi_kernel_release(&msynth->output_rfile); 259 } 260 261 /* delete given midi synth port */ 262 static void snd_seq_midisynth_delete(struct seq_midisynth *msynth) 263 { 264 if (msynth == NULL) 265 return; 266 267 if (msynth->seq_client > 0) { 268 /* delete port */ 269 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port); 270 } 271 272 if (msynth->parser) 273 snd_midi_event_free(msynth->parser); 274 } 275 276 /* register new midi synth port */ 277 static int 278 snd_seq_midisynth_register_port(struct snd_seq_device *dev) 279 { 280 struct seq_midisynth_client *client; 281 struct seq_midisynth *msynth, *ms; 282 struct snd_seq_port_info *port; 283 struct snd_rawmidi_info *info; 284 struct snd_rawmidi *rmidi = dev->private_data; 285 int newclient = 0; 286 unsigned int p, ports; 287 struct snd_seq_port_callback pcallbacks; 288 struct snd_card *card = dev->card; 289 int device = dev->device; 290 unsigned int input_count = 0, output_count = 0; 291 292 if (snd_BUG_ON(!card || device < 0 || device >= SNDRV_RAWMIDI_DEVICES)) 293 return -EINVAL; 294 info = kmalloc(sizeof(*info), GFP_KERNEL); 295 if (! info) 296 return -ENOMEM; 297 info->device = device; 298 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 299 info->subdevice = 0; 300 if (snd_rawmidi_info_select(card, info) >= 0) 301 output_count = info->subdevices_count; 302 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 303 if (snd_rawmidi_info_select(card, info) >= 0) { 304 input_count = info->subdevices_count; 305 } 306 ports = output_count; 307 if (ports < input_count) 308 ports = input_count; 309 if (ports == 0) { 310 kfree(info); 311 return -ENODEV; 312 } 313 if (ports > (256 / SNDRV_RAWMIDI_DEVICES)) 314 ports = 256 / SNDRV_RAWMIDI_DEVICES; 315 316 mutex_lock(®ister_mutex); 317 client = synths[card->number]; 318 if (client == NULL) { 319 newclient = 1; 320 client = kzalloc(sizeof(*client), GFP_KERNEL); 321 if (client == NULL) { 322 mutex_unlock(®ister_mutex); 323 kfree(info); 324 return -ENOMEM; 325 } 326 client->seq_client = 327 snd_seq_create_kernel_client( 328 card, 0, "%s", card->shortname[0] ? 329 (const char *)card->shortname : "External MIDI"); 330 if (client->seq_client < 0) { 331 kfree(client); 332 mutex_unlock(®ister_mutex); 333 kfree(info); 334 return -ENOMEM; 335 } 336 } 337 338 msynth = kcalloc(ports, sizeof(struct seq_midisynth), GFP_KERNEL); 339 port = kmalloc(sizeof(*port), GFP_KERNEL); 340 if (msynth == NULL || port == NULL) 341 goto __nomem; 342 343 for (p = 0; p < ports; p++) { 344 ms = &msynth[p]; 345 346 if (snd_seq_midisynth_new(ms, card, device, p) < 0) 347 goto __nomem; 348 349 /* declare port */ 350 memset(port, 0, sizeof(*port)); 351 port->addr.client = client->seq_client; 352 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p; 353 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; 354 memset(info, 0, sizeof(*info)); 355 info->device = device; 356 if (p < output_count) 357 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 358 else 359 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 360 info->subdevice = p; 361 if (snd_rawmidi_info_select(card, info) >= 0) 362 strcpy(port->name, info->subname); 363 if (! port->name[0]) { 364 if (info->name[0]) { 365 if (ports > 1) 366 snprintf(port->name, sizeof(port->name), "%s-%d", info->name, p); 367 else 368 snprintf(port->name, sizeof(port->name), "%s", info->name); 369 } else { 370 /* last resort */ 371 if (ports > 1) 372 sprintf(port->name, "MIDI %d-%d-%d", card->number, device, p); 373 else 374 sprintf(port->name, "MIDI %d-%d", card->number, device); 375 } 376 } 377 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count) 378 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 379 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count) 380 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 381 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) && 382 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX) 383 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 384 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC 385 | SNDRV_SEQ_PORT_TYPE_HARDWARE 386 | SNDRV_SEQ_PORT_TYPE_PORT; 387 port->midi_channels = 16; 388 memset(&pcallbacks, 0, sizeof(pcallbacks)); 389 pcallbacks.owner = THIS_MODULE; 390 pcallbacks.private_data = ms; 391 pcallbacks.subscribe = midisynth_subscribe; 392 pcallbacks.unsubscribe = midisynth_unsubscribe; 393 pcallbacks.use = midisynth_use; 394 pcallbacks.unuse = midisynth_unuse; 395 pcallbacks.event_input = event_process_midi; 396 port->kernel = &pcallbacks; 397 if (rmidi->ops && rmidi->ops->get_port_info) 398 rmidi->ops->get_port_info(rmidi, p, port); 399 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0) 400 goto __nomem; 401 ms->seq_client = client->seq_client; 402 ms->seq_port = port->addr.port; 403 } 404 client->ports_per_device[device] = ports; 405 client->ports[device] = msynth; 406 client->num_ports++; 407 if (newclient) 408 synths[card->number] = client; 409 mutex_unlock(®ister_mutex); 410 kfree(info); 411 kfree(port); 412 return 0; /* success */ 413 414 __nomem: 415 if (msynth != NULL) { 416 for (p = 0; p < ports; p++) 417 snd_seq_midisynth_delete(&msynth[p]); 418 kfree(msynth); 419 } 420 if (newclient) { 421 snd_seq_delete_kernel_client(client->seq_client); 422 kfree(client); 423 } 424 kfree(info); 425 kfree(port); 426 mutex_unlock(®ister_mutex); 427 return -ENOMEM; 428 } 429 430 /* release midi synth port */ 431 static int 432 snd_seq_midisynth_unregister_port(struct snd_seq_device *dev) 433 { 434 struct seq_midisynth_client *client; 435 struct seq_midisynth *msynth; 436 struct snd_card *card = dev->card; 437 int device = dev->device, p, ports; 438 439 mutex_lock(®ister_mutex); 440 client = synths[card->number]; 441 if (client == NULL || client->ports[device] == NULL) { 442 mutex_unlock(®ister_mutex); 443 return -ENODEV; 444 } 445 ports = client->ports_per_device[device]; 446 client->ports_per_device[device] = 0; 447 msynth = client->ports[device]; 448 client->ports[device] = NULL; 449 for (p = 0; p < ports; p++) 450 snd_seq_midisynth_delete(&msynth[p]); 451 kfree(msynth); 452 client->num_ports--; 453 if (client->num_ports <= 0) { 454 snd_seq_delete_kernel_client(client->seq_client); 455 synths[card->number] = NULL; 456 kfree(client); 457 } 458 mutex_unlock(®ister_mutex); 459 return 0; 460 } 461 462 463 static int __init alsa_seq_midi_init(void) 464 { 465 static struct snd_seq_dev_ops ops = { 466 snd_seq_midisynth_register_port, 467 snd_seq_midisynth_unregister_port, 468 }; 469 memset(&synths, 0, sizeof(synths)); 470 snd_seq_autoload_lock(); 471 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0); 472 snd_seq_autoload_unlock(); 473 return 0; 474 } 475 476 static void __exit alsa_seq_midi_exit(void) 477 { 478 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH); 479 } 480 481 module_init(alsa_seq_midi_init) 482 module_exit(alsa_seq_midi_exit) 483