1 /* 2 * Generic MIDI synth driver for ALSA sequencer 3 * Copyright (c) 1998 by Frank van de Pol <[email protected]> 4 * Jaroslav Kysela <[email protected]> 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 <[email protected]>, Jaroslav Kysela <[email protected]>"); 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 if (printk_ratelimit()) 124 snd_printk(KERN_ERR "MIDI output buffer overrun\n"); 125 return -ENOMEM; 126 } 127 if (snd_rawmidi_kernel_write(substream, buf, count) < count) 128 return -EINVAL; 129 return 0; 130 } 131 132 static int event_process_midi(struct snd_seq_event *ev, int direct, 133 void *private_data, int atomic, int hop) 134 { 135 struct seq_midisynth *msynth = private_data; 136 unsigned char msg[10]; /* buffer for constructing midi messages */ 137 struct snd_rawmidi_substream *substream; 138 int len; 139 140 if (snd_BUG_ON(!msynth)) 141 return -EINVAL; 142 substream = msynth->output_rfile.output; 143 if (substream == NULL) 144 return -ENODEV; 145 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */ 146 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) { 147 /* invalid event */ 148 snd_printd("seq_midi: invalid sysex event flags = 0x%x\n", ev->flags); 149 return 0; 150 } 151 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream); 152 snd_midi_event_reset_decode(msynth->parser); 153 } else { 154 if (msynth->parser == NULL) 155 return -EIO; 156 len = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev); 157 if (len < 0) 158 return 0; 159 if (dump_midi(substream, msg, len) < 0) 160 snd_midi_event_reset_decode(msynth->parser); 161 } 162 return 0; 163 } 164 165 166 static int snd_seq_midisynth_new(struct seq_midisynth *msynth, 167 struct snd_card *card, 168 int device, 169 int subdevice) 170 { 171 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0) 172 return -ENOMEM; 173 msynth->card = card; 174 msynth->device = device; 175 msynth->subdevice = subdevice; 176 return 0; 177 } 178 179 /* open associated midi device for input */ 180 static int midisynth_subscribe(void *private_data, struct snd_seq_port_subscribe *info) 181 { 182 int err; 183 struct seq_midisynth *msynth = private_data; 184 struct snd_rawmidi_runtime *runtime; 185 struct snd_rawmidi_params params; 186 187 /* open midi port */ 188 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device, 189 msynth->subdevice, 190 SNDRV_RAWMIDI_LFLG_INPUT, 191 &msynth->input_rfile)) < 0) { 192 snd_printd("midi input open failed!!!\n"); 193 return err; 194 } 195 runtime = msynth->input_rfile.input->runtime; 196 memset(¶ms, 0, sizeof(params)); 197 params.avail_min = 1; 198 params.buffer_size = input_buffer_size; 199 if ((err = snd_rawmidi_input_params(msynth->input_rfile.input, ¶ms)) < 0) { 200 snd_rawmidi_kernel_release(&msynth->input_rfile); 201 return err; 202 } 203 snd_midi_event_reset_encode(msynth->parser); 204 runtime->event = snd_midi_input_event; 205 runtime->private_data = msynth; 206 snd_rawmidi_kernel_read(msynth->input_rfile.input, NULL, 0); 207 return 0; 208 } 209 210 /* close associated midi device for input */ 211 static int midisynth_unsubscribe(void *private_data, struct snd_seq_port_subscribe *info) 212 { 213 int err; 214 struct seq_midisynth *msynth = private_data; 215 216 if (snd_BUG_ON(!msynth->input_rfile.input)) 217 return -EINVAL; 218 err = snd_rawmidi_kernel_release(&msynth->input_rfile); 219 return err; 220 } 221 222 /* open associated midi device for output */ 223 static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info) 224 { 225 int err; 226 struct seq_midisynth *msynth = private_data; 227 struct snd_rawmidi_params params; 228 229 /* open midi port */ 230 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device, 231 msynth->subdevice, 232 SNDRV_RAWMIDI_LFLG_OUTPUT, 233 &msynth->output_rfile)) < 0) { 234 snd_printd("midi output open failed!!!\n"); 235 return err; 236 } 237 memset(¶ms, 0, sizeof(params)); 238 params.avail_min = 1; 239 params.buffer_size = output_buffer_size; 240 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) { 241 snd_rawmidi_kernel_release(&msynth->output_rfile); 242 return err; 243 } 244 snd_midi_event_reset_decode(msynth->parser); 245 return 0; 246 } 247 248 /* close associated midi device for output */ 249 static int midisynth_unuse(void *private_data, struct snd_seq_port_subscribe *info) 250 { 251 struct seq_midisynth *msynth = private_data; 252 unsigned char buf = 0xff; /* MIDI reset */ 253 254 if (snd_BUG_ON(!msynth->output_rfile.output)) 255 return -EINVAL; 256 /* sending single MIDI reset message to shut the device up */ 257 snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1); 258 snd_rawmidi_drain_output(msynth->output_rfile.output); 259 return snd_rawmidi_kernel_release(&msynth->output_rfile); 260 } 261 262 /* delete given midi synth port */ 263 static void snd_seq_midisynth_delete(struct seq_midisynth *msynth) 264 { 265 if (msynth == NULL) 266 return; 267 268 if (msynth->seq_client > 0) { 269 /* delete port */ 270 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port); 271 } 272 273 if (msynth->parser) 274 snd_midi_event_free(msynth->parser); 275 } 276 277 /* register new midi synth port */ 278 static int 279 snd_seq_midisynth_register_port(struct snd_seq_device *dev) 280 { 281 struct seq_midisynth_client *client; 282 struct seq_midisynth *msynth, *ms; 283 struct snd_seq_port_info *port; 284 struct snd_rawmidi_info *info; 285 struct snd_rawmidi *rmidi = dev->private_data; 286 int newclient = 0; 287 unsigned int p, ports; 288 struct snd_seq_port_callback pcallbacks; 289 struct snd_card *card = dev->card; 290 int device = dev->device; 291 unsigned int input_count = 0, output_count = 0; 292 293 if (snd_BUG_ON(!card || device < 0 || device >= SNDRV_RAWMIDI_DEVICES)) 294 return -EINVAL; 295 info = kmalloc(sizeof(*info), GFP_KERNEL); 296 if (! info) 297 return -ENOMEM; 298 info->device = device; 299 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 300 info->subdevice = 0; 301 if (snd_rawmidi_info_select(card, info) >= 0) 302 output_count = info->subdevices_count; 303 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 304 if (snd_rawmidi_info_select(card, info) >= 0) { 305 input_count = info->subdevices_count; 306 } 307 ports = output_count; 308 if (ports < input_count) 309 ports = input_count; 310 if (ports == 0) { 311 kfree(info); 312 return -ENODEV; 313 } 314 if (ports > (256 / SNDRV_RAWMIDI_DEVICES)) 315 ports = 256 / SNDRV_RAWMIDI_DEVICES; 316 317 mutex_lock(®ister_mutex); 318 client = synths[card->number]; 319 if (client == NULL) { 320 newclient = 1; 321 client = kzalloc(sizeof(*client), GFP_KERNEL); 322 if (client == NULL) { 323 mutex_unlock(®ister_mutex); 324 kfree(info); 325 return -ENOMEM; 326 } 327 client->seq_client = 328 snd_seq_create_kernel_client( 329 card, 0, "%s", card->shortname[0] ? 330 (const char *)card->shortname : "External MIDI"); 331 if (client->seq_client < 0) { 332 kfree(client); 333 mutex_unlock(®ister_mutex); 334 kfree(info); 335 return -ENOMEM; 336 } 337 } 338 339 msynth = kcalloc(ports, sizeof(struct seq_midisynth), GFP_KERNEL); 340 port = kmalloc(sizeof(*port), GFP_KERNEL); 341 if (msynth == NULL || port == NULL) 342 goto __nomem; 343 344 for (p = 0; p < ports; p++) { 345 ms = &msynth[p]; 346 347 if (snd_seq_midisynth_new(ms, card, device, p) < 0) 348 goto __nomem; 349 350 /* declare port */ 351 memset(port, 0, sizeof(*port)); 352 port->addr.client = client->seq_client; 353 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p; 354 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; 355 memset(info, 0, sizeof(*info)); 356 info->device = device; 357 if (p < output_count) 358 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 359 else 360 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 361 info->subdevice = p; 362 if (snd_rawmidi_info_select(card, info) >= 0) 363 strcpy(port->name, info->subname); 364 if (! port->name[0]) { 365 if (info->name[0]) { 366 if (ports > 1) 367 snprintf(port->name, sizeof(port->name), "%s-%d", info->name, p); 368 else 369 snprintf(port->name, sizeof(port->name), "%s", info->name); 370 } else { 371 /* last resort */ 372 if (ports > 1) 373 sprintf(port->name, "MIDI %d-%d-%d", card->number, device, p); 374 else 375 sprintf(port->name, "MIDI %d-%d", card->number, device); 376 } 377 } 378 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count) 379 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 380 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count) 381 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 382 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) && 383 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX) 384 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 385 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC 386 | SNDRV_SEQ_PORT_TYPE_HARDWARE 387 | SNDRV_SEQ_PORT_TYPE_PORT; 388 port->midi_channels = 16; 389 memset(&pcallbacks, 0, sizeof(pcallbacks)); 390 pcallbacks.owner = THIS_MODULE; 391 pcallbacks.private_data = ms; 392 pcallbacks.subscribe = midisynth_subscribe; 393 pcallbacks.unsubscribe = midisynth_unsubscribe; 394 pcallbacks.use = midisynth_use; 395 pcallbacks.unuse = midisynth_unuse; 396 pcallbacks.event_input = event_process_midi; 397 port->kernel = &pcallbacks; 398 if (rmidi->ops && rmidi->ops->get_port_info) 399 rmidi->ops->get_port_info(rmidi, p, port); 400 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0) 401 goto __nomem; 402 ms->seq_client = client->seq_client; 403 ms->seq_port = port->addr.port; 404 } 405 client->ports_per_device[device] = ports; 406 client->ports[device] = msynth; 407 client->num_ports++; 408 if (newclient) 409 synths[card->number] = client; 410 mutex_unlock(®ister_mutex); 411 kfree(info); 412 kfree(port); 413 return 0; /* success */ 414 415 __nomem: 416 if (msynth != NULL) { 417 for (p = 0; p < ports; p++) 418 snd_seq_midisynth_delete(&msynth[p]); 419 kfree(msynth); 420 } 421 if (newclient) { 422 snd_seq_delete_kernel_client(client->seq_client); 423 kfree(client); 424 } 425 kfree(info); 426 kfree(port); 427 mutex_unlock(®ister_mutex); 428 return -ENOMEM; 429 } 430 431 /* release midi synth port */ 432 static int 433 snd_seq_midisynth_unregister_port(struct snd_seq_device *dev) 434 { 435 struct seq_midisynth_client *client; 436 struct seq_midisynth *msynth; 437 struct snd_card *card = dev->card; 438 int device = dev->device, p, ports; 439 440 mutex_lock(®ister_mutex); 441 client = synths[card->number]; 442 if (client == NULL || client->ports[device] == NULL) { 443 mutex_unlock(®ister_mutex); 444 return -ENODEV; 445 } 446 ports = client->ports_per_device[device]; 447 client->ports_per_device[device] = 0; 448 msynth = client->ports[device]; 449 client->ports[device] = NULL; 450 for (p = 0; p < ports; p++) 451 snd_seq_midisynth_delete(&msynth[p]); 452 kfree(msynth); 453 client->num_ports--; 454 if (client->num_ports <= 0) { 455 snd_seq_delete_kernel_client(client->seq_client); 456 synths[card->number] = NULL; 457 kfree(client); 458 } 459 mutex_unlock(®ister_mutex); 460 return 0; 461 } 462 463 464 static int __init alsa_seq_midi_init(void) 465 { 466 static struct snd_seq_dev_ops ops = { 467 snd_seq_midisynth_register_port, 468 snd_seq_midisynth_unregister_port, 469 }; 470 memset(&synths, 0, sizeof(synths)); 471 snd_seq_autoload_lock(); 472 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0); 473 snd_seq_autoload_unlock(); 474 return 0; 475 } 476 477 static void __exit alsa_seq_midi_exit(void) 478 { 479 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH); 480 } 481 482 module_init(alsa_seq_midi_init) 483 module_exit(alsa_seq_midi_exit) 484