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