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 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(seq_midisynth_t *msynth, 165 snd_card_t *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, snd_seq_port_subscribe_t *info) 179 { 180 int err; 181 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 182 snd_rawmidi_runtime_t *runtime; 183 snd_rawmidi_params_t params; 184 185 /* open midi port */ 186 if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_INPUT, &msynth->input_rfile)) < 0) { 187 snd_printd("midi input open failed!!!\n"); 188 return err; 189 } 190 runtime = msynth->input_rfile.input->runtime; 191 memset(¶ms, 0, sizeof(params)); 192 params.avail_min = 1; 193 params.buffer_size = input_buffer_size; 194 if ((err = snd_rawmidi_input_params(msynth->input_rfile.input, ¶ms)) < 0) { 195 snd_rawmidi_kernel_release(&msynth->input_rfile); 196 return err; 197 } 198 snd_midi_event_reset_encode(msynth->parser); 199 runtime->event = snd_midi_input_event; 200 runtime->private_data = msynth; 201 snd_rawmidi_kernel_read(msynth->input_rfile.input, NULL, 0); 202 return 0; 203 } 204 205 /* close associated midi device for input */ 206 static int midisynth_unsubscribe(void *private_data, snd_seq_port_subscribe_t *info) 207 { 208 int err; 209 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 210 211 snd_assert(msynth->input_rfile.input != NULL, return -EINVAL); 212 err = snd_rawmidi_kernel_release(&msynth->input_rfile); 213 return err; 214 } 215 216 /* open associated midi device for output */ 217 static int midisynth_use(void *private_data, snd_seq_port_subscribe_t *info) 218 { 219 int err; 220 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 221 snd_rawmidi_params_t params; 222 223 /* open midi port */ 224 if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_OUTPUT, &msynth->output_rfile)) < 0) { 225 snd_printd("midi output open failed!!!\n"); 226 return err; 227 } 228 memset(¶ms, 0, sizeof(params)); 229 params.avail_min = 1; 230 params.buffer_size = output_buffer_size; 231 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) { 232 snd_rawmidi_kernel_release(&msynth->output_rfile); 233 return err; 234 } 235 snd_midi_event_reset_decode(msynth->parser); 236 return 0; 237 } 238 239 /* close associated midi device for output */ 240 static int midisynth_unuse(void *private_data, snd_seq_port_subscribe_t *info) 241 { 242 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data; 243 unsigned char buf = 0xff; /* MIDI reset */ 244 245 snd_assert(msynth->output_rfile.output != NULL, return -EINVAL); 246 /* sending single MIDI reset message to shut the device up */ 247 snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1); 248 snd_rawmidi_drain_output(msynth->output_rfile.output); 249 return snd_rawmidi_kernel_release(&msynth->output_rfile); 250 } 251 252 /* delete given midi synth port */ 253 static void snd_seq_midisynth_delete(seq_midisynth_t *msynth) 254 { 255 if (msynth == NULL) 256 return; 257 258 if (msynth->seq_client > 0) { 259 /* delete port */ 260 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port); 261 } 262 263 if (msynth->parser) 264 snd_midi_event_free(msynth->parser); 265 } 266 267 /* set our client name */ 268 static int set_client_name(seq_midisynth_client_t *client, snd_card_t *card, 269 snd_rawmidi_info_t *rmidi) 270 { 271 snd_seq_client_info_t cinfo; 272 const char *name; 273 274 memset(&cinfo, 0, sizeof(cinfo)); 275 cinfo.client = client->seq_client; 276 cinfo.type = KERNEL_CLIENT; 277 name = rmidi->name[0] ? (const char *)rmidi->name : "External MIDI"; 278 strlcpy(cinfo.name, name, sizeof(cinfo.name)); 279 return snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, &cinfo); 280 } 281 282 /* register new midi synth port */ 283 static int 284 snd_seq_midisynth_register_port(snd_seq_device_t *dev) 285 { 286 seq_midisynth_client_t *client; 287 seq_midisynth_t *msynth, *ms; 288 snd_seq_port_info_t *port; 289 snd_rawmidi_info_t *info; 290 int newclient = 0; 291 unsigned int p, ports; 292 snd_seq_client_callback_t callbacks; 293 snd_seq_port_callback_t pcallbacks; 294 snd_card_t *card = dev->card; 295 int device = dev->device; 296 unsigned int input_count = 0, output_count = 0; 297 298 snd_assert(card != NULL && device >= 0 && device < SNDRV_RAWMIDI_DEVICES, return -EINVAL); 299 info = kmalloc(sizeof(*info), GFP_KERNEL); 300 if (! info) 301 return -ENOMEM; 302 info->device = device; 303 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 304 info->subdevice = 0; 305 if (snd_rawmidi_info_select(card, info) >= 0) 306 output_count = info->subdevices_count; 307 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 308 if (snd_rawmidi_info_select(card, info) >= 0) { 309 input_count = info->subdevices_count; 310 } 311 ports = output_count; 312 if (ports < input_count) 313 ports = input_count; 314 if (ports == 0) { 315 kfree(info); 316 return -ENODEV; 317 } 318 if (ports > (256 / SNDRV_RAWMIDI_DEVICES)) 319 ports = 256 / SNDRV_RAWMIDI_DEVICES; 320 321 down(®ister_mutex); 322 client = synths[card->number]; 323 if (client == NULL) { 324 newclient = 1; 325 client = kcalloc(1, sizeof(*client), GFP_KERNEL); 326 if (client == NULL) { 327 up(®ister_mutex); 328 kfree(info); 329 return -ENOMEM; 330 } 331 memset(&callbacks, 0, sizeof(callbacks)); 332 callbacks.private_data = client; 333 callbacks.allow_input = callbacks.allow_output = 1; 334 client->seq_client = snd_seq_create_kernel_client(card, 0, &callbacks); 335 if (client->seq_client < 0) { 336 kfree(client); 337 up(®ister_mutex); 338 kfree(info); 339 return -ENOMEM; 340 } 341 set_client_name(client, card, info); 342 } else if (device == 0) 343 set_client_name(client, card, info); /* use the first device's name */ 344 345 msynth = kcalloc(ports, sizeof(seq_midisynth_t), GFP_KERNEL); 346 port = kmalloc(sizeof(*port), GFP_KERNEL); 347 if (msynth == NULL || port == NULL) 348 goto __nomem; 349 350 for (p = 0; p < ports; p++) { 351 ms = &msynth[p]; 352 353 if (snd_seq_midisynth_new(ms, card, device, p) < 0) 354 goto __nomem; 355 356 /* declare port */ 357 memset(port, 0, sizeof(*port)); 358 port->addr.client = client->seq_client; 359 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p; 360 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; 361 memset(info, 0, sizeof(*info)); 362 info->device = device; 363 if (p < output_count) 364 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 365 else 366 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 367 info->subdevice = p; 368 if (snd_rawmidi_info_select(card, info) >= 0) 369 strcpy(port->name, info->subname); 370 if (! port->name[0]) { 371 if (info->name[0]) { 372 if (ports > 1) 373 snprintf(port->name, sizeof(port->name), "%s-%d", info->name, p); 374 else 375 snprintf(port->name, sizeof(port->name), "%s", info->name); 376 } else { 377 /* last resort */ 378 if (ports > 1) 379 sprintf(port->name, "MIDI %d-%d-%d", card->number, device, p); 380 else 381 sprintf(port->name, "MIDI %d-%d", card->number, device); 382 } 383 } 384 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count) 385 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 386 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count) 387 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 388 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) && 389 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX) 390 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 391 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC; 392 port->midi_channels = 16; 393 memset(&pcallbacks, 0, sizeof(pcallbacks)); 394 pcallbacks.owner = THIS_MODULE; 395 pcallbacks.private_data = ms; 396 pcallbacks.subscribe = midisynth_subscribe; 397 pcallbacks.unsubscribe = midisynth_unsubscribe; 398 pcallbacks.use = midisynth_use; 399 pcallbacks.unuse = midisynth_unuse; 400 pcallbacks.event_input = event_process_midi; 401 port->kernel = &pcallbacks; 402 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0) 403 goto __nomem; 404 ms->seq_client = client->seq_client; 405 ms->seq_port = port->addr.port; 406 } 407 client->ports_per_device[device] = ports; 408 client->ports[device] = msynth; 409 client->num_ports++; 410 if (newclient) 411 synths[card->number] = client; 412 up(®ister_mutex); 413 kfree(info); 414 kfree(port); 415 return 0; /* success */ 416 417 __nomem: 418 if (msynth != NULL) { 419 for (p = 0; p < ports; p++) 420 snd_seq_midisynth_delete(&msynth[p]); 421 kfree(msynth); 422 } 423 if (newclient) { 424 snd_seq_delete_kernel_client(client->seq_client); 425 kfree(client); 426 } 427 kfree(info); 428 kfree(port); 429 up(®ister_mutex); 430 return -ENOMEM; 431 } 432 433 /* release midi synth port */ 434 static int 435 snd_seq_midisynth_unregister_port(snd_seq_device_t *dev) 436 { 437 seq_midisynth_client_t *client; 438 seq_midisynth_t *msynth; 439 snd_card_t *card = dev->card; 440 int device = dev->device, p, ports; 441 442 down(®ister_mutex); 443 client = synths[card->number]; 444 if (client == NULL || client->ports[device] == NULL) { 445 up(®ister_mutex); 446 return -ENODEV; 447 } 448 ports = client->ports_per_device[device]; 449 client->ports_per_device[device] = 0; 450 msynth = client->ports[device]; 451 client->ports[device] = NULL; 452 snd_runtime_check(msynth != NULL || ports <= 0, goto __skip); 453 for (p = 0; p < ports; p++) 454 snd_seq_midisynth_delete(&msynth[p]); 455 kfree(msynth); 456 __skip: 457 client->num_ports--; 458 if (client->num_ports <= 0) { 459 snd_seq_delete_kernel_client(client->seq_client); 460 synths[card->number] = NULL; 461 kfree(client); 462 } 463 up(®ister_mutex); 464 return 0; 465 } 466 467 468 static int __init alsa_seq_midi_init(void) 469 { 470 static snd_seq_dev_ops_t ops = { 471 snd_seq_midisynth_register_port, 472 snd_seq_midisynth_unregister_port, 473 }; 474 memset(&synths, 0, sizeof(synths)); 475 snd_seq_autoload_lock(); 476 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0); 477 snd_seq_autoload_unlock(); 478 return 0; 479 } 480 481 static void __exit alsa_seq_midi_exit(void) 482 { 483 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH); 484 } 485 486 module_init(alsa_seq_midi_init) 487 module_exit(alsa_seq_midi_exit) 488