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@suse.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 <asm/semaphore.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@suse.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 typedef struct { 55 snd_card_t *card; 56 int device; 57 int subdevice; 58 snd_rawmidi_file_t input_rfile; 59 snd_rawmidi_file_t output_rfile; 60 int seq_client; 61 int seq_port; 62 snd_midi_event_t *parser; 63 } seq_midisynth_t; 64 65 typedef struct { 66 int seq_client; 67 int num_ports; 68 int ports_per_device[SNDRV_RAWMIDI_DEVICES]; 69 seq_midisynth_t *ports[SNDRV_RAWMIDI_DEVICES]; 70 } seq_midisynth_client_t; 71 72 static seq_midisynth_client_t *synths[SNDRV_CARDS]; 73 static DECLARE_MUTEX(register_mutex); 74 75 /* handle rawmidi input event (MIDI v1.0 stream) */ 76 static void snd_midi_input_event(snd_rawmidi_substream_t * substream) 77 { 78 snd_rawmidi_runtime_t *runtime; 79 seq_midisynth_t *msynth; 80 snd_seq_event_t ev; 81 char buf[16], *pbuf; 82 long res, count; 83 84 if (substream == NULL) 85 return; 86 runtime = substream->runtime; 87 msynth = (seq_midisynth_t *) 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(snd_rawmidi_substream_t *substream, const char *buf, int count) 116 { 117 snd_rawmidi_runtime_t *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(snd_seq_event_t * ev, int direct, 132 void *private_data, int atomic, int hop) 133 { 134 seq_midisynth_t *msynth = (seq_midisynth_t *) private_data; 135 unsigned char msg[10]; /* buffer for constructing midi messages */ 136 snd_rawmidi_substream_t *substream; 137 int res; 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 res = snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream); 150 snd_midi_event_reset_decode(msynth->parser); 151 if (res < 0) 152 return res; 153 } else { 154 if (msynth->parser == NULL) 155 return -EIO; 156 res = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev); 157 if (res < 0) 158 return res; 159 if ((res = dump_midi(substream, msg, res)) < 0) { 160 snd_midi_event_reset_decode(msynth->parser); 161 return res; 162 } 163 } 164 return 0; 165 } 166 167 168 static int snd_seq_midisynth_new(seq_midisynth_t *msynth, 169 snd_card_t *card, 170 int device, 171 int subdevice) 172 { 173 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0) 174 return -ENOMEM; 175 msynth->card = card; 176 msynth->device = device; 177 msynth->subdevice = subdevice; 178 return 0; 179 } 180 181 /* open associated midi device for input */ 182 static int midisynth_subscribe(void *private_data, snd_seq_port_subscribe_t *info) 183 { 184 int err; 185 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 186 snd_rawmidi_runtime_t *runtime; 187 snd_rawmidi_params_t params; 188 189 /* open midi port */ 190 if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_INPUT, &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, snd_seq_port_subscribe_t *info) 211 { 212 int err; 213 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 214 215 snd_assert(msynth->input_rfile.input != NULL, return -EINVAL); 216 err = snd_rawmidi_kernel_release(&msynth->input_rfile); 217 return err; 218 } 219 220 /* open associated midi device for output */ 221 static int midisynth_use(void *private_data, snd_seq_port_subscribe_t *info) 222 { 223 int err; 224 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 225 snd_rawmidi_params_t params; 226 227 /* open midi port */ 228 if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_OUTPUT, &msynth->output_rfile)) < 0) { 229 snd_printd("midi output open failed!!!\n"); 230 return err; 231 } 232 memset(¶ms, 0, sizeof(params)); 233 params.avail_min = 1; 234 params.buffer_size = output_buffer_size; 235 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) { 236 snd_rawmidi_kernel_release(&msynth->output_rfile); 237 return err; 238 } 239 snd_midi_event_reset_decode(msynth->parser); 240 return 0; 241 } 242 243 /* close associated midi device for output */ 244 static int midisynth_unuse(void *private_data, snd_seq_port_subscribe_t *info) 245 { 246 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 247 unsigned char buf = 0xff; /* MIDI reset */ 248 249 snd_assert(msynth->output_rfile.output != NULL, return -EINVAL); 250 /* sending single MIDI reset message to shut the device up */ 251 snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1); 252 snd_rawmidi_drain_output(msynth->output_rfile.output); 253 return snd_rawmidi_kernel_release(&msynth->output_rfile); 254 } 255 256 /* delete given midi synth port */ 257 static void snd_seq_midisynth_delete(seq_midisynth_t *msynth) 258 { 259 if (msynth == NULL) 260 return; 261 262 if (msynth->seq_client > 0) { 263 /* delete port */ 264 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port); 265 } 266 267 if (msynth->parser) 268 snd_midi_event_free(msynth->parser); 269 } 270 271 /* set our client name */ 272 static int set_client_name(seq_midisynth_client_t *client, snd_card_t *card, 273 snd_rawmidi_info_t *rmidi) 274 { 275 snd_seq_client_info_t cinfo; 276 const char *name; 277 278 memset(&cinfo, 0, sizeof(cinfo)); 279 cinfo.client = client->seq_client; 280 cinfo.type = KERNEL_CLIENT; 281 name = rmidi->name[0] ? (const char *)rmidi->name : "External MIDI"; 282 strlcpy(cinfo.name, name, sizeof(cinfo.name)); 283 return snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, &cinfo); 284 } 285 286 /* register new midi synth port */ 287 static int 288 snd_seq_midisynth_register_port(snd_seq_device_t *dev) 289 { 290 seq_midisynth_client_t *client; 291 seq_midisynth_t *msynth, *ms; 292 snd_seq_port_info_t *port; 293 snd_rawmidi_info_t *info; 294 int newclient = 0; 295 unsigned int p, ports; 296 snd_seq_client_callback_t callbacks; 297 snd_seq_port_callback_t pcallbacks; 298 snd_card_t *card = dev->card; 299 int device = dev->device; 300 unsigned int input_count = 0, output_count = 0; 301 302 snd_assert(card != NULL && device >= 0 && device < SNDRV_RAWMIDI_DEVICES, return -EINVAL); 303 info = kmalloc(sizeof(*info), GFP_KERNEL); 304 if (! info) 305 return -ENOMEM; 306 info->device = device; 307 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 308 info->subdevice = 0; 309 if (snd_rawmidi_info_select(card, info) >= 0) 310 output_count = info->subdevices_count; 311 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 312 if (snd_rawmidi_info_select(card, info) >= 0) { 313 input_count = info->subdevices_count; 314 } 315 ports = output_count; 316 if (ports < input_count) 317 ports = input_count; 318 if (ports == 0) { 319 kfree(info); 320 return -ENODEV; 321 } 322 if (ports > (256 / SNDRV_RAWMIDI_DEVICES)) 323 ports = 256 / SNDRV_RAWMIDI_DEVICES; 324 325 down(®ister_mutex); 326 client = synths[card->number]; 327 if (client == NULL) { 328 newclient = 1; 329 client = kcalloc(1, sizeof(*client), GFP_KERNEL); 330 if (client == NULL) { 331 up(®ister_mutex); 332 kfree(info); 333 return -ENOMEM; 334 } 335 memset(&callbacks, 0, sizeof(callbacks)); 336 callbacks.private_data = client; 337 callbacks.allow_input = callbacks.allow_output = 1; 338 client->seq_client = snd_seq_create_kernel_client(card, 0, &callbacks); 339 if (client->seq_client < 0) { 340 kfree(client); 341 up(®ister_mutex); 342 kfree(info); 343 return -ENOMEM; 344 } 345 set_client_name(client, card, info); 346 } else if (device == 0) 347 set_client_name(client, card, info); /* use the first device's name */ 348 349 msynth = kcalloc(ports, sizeof(seq_midisynth_t), GFP_KERNEL); 350 port = kmalloc(sizeof(*port), GFP_KERNEL); 351 if (msynth == NULL || port == NULL) 352 goto __nomem; 353 354 for (p = 0; p < ports; p++) { 355 ms = &msynth[p]; 356 357 if (snd_seq_midisynth_new(ms, card, device, p) < 0) 358 goto __nomem; 359 360 /* declare port */ 361 memset(port, 0, sizeof(*port)); 362 port->addr.client = client->seq_client; 363 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p; 364 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; 365 memset(info, 0, sizeof(*info)); 366 info->device = device; 367 if (p < output_count) 368 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 369 else 370 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 371 info->subdevice = p; 372 if (snd_rawmidi_info_select(card, info) >= 0) 373 strcpy(port->name, info->subname); 374 if (! port->name[0]) { 375 if (info->name[0]) { 376 if (ports > 1) 377 snprintf(port->name, sizeof(port->name), "%s-%d", info->name, p); 378 else 379 snprintf(port->name, sizeof(port->name), "%s", info->name); 380 } else { 381 /* last resort */ 382 if (ports > 1) 383 sprintf(port->name, "MIDI %d-%d-%d", card->number, device, p); 384 else 385 sprintf(port->name, "MIDI %d-%d", card->number, device); 386 } 387 } 388 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count) 389 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 390 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count) 391 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 392 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) && 393 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX) 394 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 395 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC; 396 port->midi_channels = 16; 397 memset(&pcallbacks, 0, sizeof(pcallbacks)); 398 pcallbacks.owner = THIS_MODULE; 399 pcallbacks.private_data = ms; 400 pcallbacks.subscribe = midisynth_subscribe; 401 pcallbacks.unsubscribe = midisynth_unsubscribe; 402 pcallbacks.use = midisynth_use; 403 pcallbacks.unuse = midisynth_unuse; 404 pcallbacks.event_input = event_process_midi; 405 port->kernel = &pcallbacks; 406 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0) 407 goto __nomem; 408 ms->seq_client = client->seq_client; 409 ms->seq_port = port->addr.port; 410 } 411 client->ports_per_device[device] = ports; 412 client->ports[device] = msynth; 413 client->num_ports++; 414 if (newclient) 415 synths[card->number] = client; 416 up(®ister_mutex); 417 return 0; /* success */ 418 419 __nomem: 420 if (msynth != NULL) { 421 for (p = 0; p < ports; p++) 422 snd_seq_midisynth_delete(&msynth[p]); 423 kfree(msynth); 424 } 425 if (newclient) { 426 snd_seq_delete_kernel_client(client->seq_client); 427 kfree(client); 428 } 429 kfree(info); 430 kfree(port); 431 up(®ister_mutex); 432 return -ENOMEM; 433 } 434 435 /* release midi synth port */ 436 static int 437 snd_seq_midisynth_unregister_port(snd_seq_device_t *dev) 438 { 439 seq_midisynth_client_t *client; 440 seq_midisynth_t *msynth; 441 snd_card_t *card = dev->card; 442 int device = dev->device, p, ports; 443 444 down(®ister_mutex); 445 client = synths[card->number]; 446 if (client == NULL || client->ports[device] == NULL) { 447 up(®ister_mutex); 448 return -ENODEV; 449 } 450 ports = client->ports_per_device[device]; 451 client->ports_per_device[device] = 0; 452 msynth = client->ports[device]; 453 client->ports[device] = NULL; 454 snd_runtime_check(msynth != NULL || ports <= 0, goto __skip); 455 for (p = 0; p < ports; p++) 456 snd_seq_midisynth_delete(&msynth[p]); 457 kfree(msynth); 458 __skip: 459 client->num_ports--; 460 if (client->num_ports <= 0) { 461 snd_seq_delete_kernel_client(client->seq_client); 462 synths[card->number] = NULL; 463 kfree(client); 464 } 465 up(®ister_mutex); 466 return 0; 467 } 468 469 470 static int __init alsa_seq_midi_init(void) 471 { 472 static snd_seq_dev_ops_t ops = { 473 snd_seq_midisynth_register_port, 474 snd_seq_midisynth_unregister_port, 475 }; 476 memset(&synths, 0, sizeof(synths)); 477 snd_seq_autoload_lock(); 478 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0); 479 snd_seq_autoload_unlock(); 480 return 0; 481 } 482 483 static void __exit alsa_seq_midi_exit(void) 484 { 485 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH); 486 } 487 488 module_init(alsa_seq_midi_init) 489 module_exit(alsa_seq_midi_exit) 490