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/module.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 if (printk_ratelimit()) 124 pr_err("ALSA: seq_midi: 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 pr_debug("ALSA: 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 pr_debug("ALSA: seq_midi: 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 pr_debug("ALSA: seq_midi: 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 params.no_active_sensing = 1; 241 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) { 242 snd_rawmidi_kernel_release(&msynth->output_rfile); 243 return err; 244 } 245 snd_midi_event_reset_decode(msynth->parser); 246 return 0; 247 } 248 249 /* close associated midi device for output */ 250 static int midisynth_unuse(void *private_data, struct snd_seq_port_subscribe *info) 251 { 252 struct seq_midisynth *msynth = private_data; 253 254 if (snd_BUG_ON(!msynth->output_rfile.output)) 255 return -EINVAL; 256 snd_rawmidi_drain_output(msynth->output_rfile.output); 257 return snd_rawmidi_kernel_release(&msynth->output_rfile); 258 } 259 260 /* delete given midi synth port */ 261 static void snd_seq_midisynth_delete(struct seq_midisynth *msynth) 262 { 263 if (msynth == NULL) 264 return; 265 266 if (msynth->seq_client > 0) { 267 /* delete port */ 268 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port); 269 } 270 271 snd_midi_event_free(msynth->parser); 272 } 273 274 /* register new midi synth port */ 275 static int 276 snd_seq_midisynth_register_port(struct snd_seq_device *dev) 277 { 278 struct seq_midisynth_client *client; 279 struct seq_midisynth *msynth, *ms; 280 struct snd_seq_port_info *port; 281 struct snd_rawmidi_info *info; 282 struct snd_rawmidi *rmidi = dev->private_data; 283 int newclient = 0; 284 unsigned int p, ports; 285 struct snd_seq_port_callback pcallbacks; 286 struct snd_card *card = dev->card; 287 int device = dev->device; 288 unsigned int input_count = 0, output_count = 0; 289 290 if (snd_BUG_ON(!card || device < 0 || device >= SNDRV_RAWMIDI_DEVICES)) 291 return -EINVAL; 292 info = kmalloc(sizeof(*info), GFP_KERNEL); 293 if (! info) 294 return -ENOMEM; 295 info->device = device; 296 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 297 info->subdevice = 0; 298 if (snd_rawmidi_info_select(card, info) >= 0) 299 output_count = info->subdevices_count; 300 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 301 if (snd_rawmidi_info_select(card, info) >= 0) { 302 input_count = info->subdevices_count; 303 } 304 ports = output_count; 305 if (ports < input_count) 306 ports = input_count; 307 if (ports == 0) { 308 kfree(info); 309 return -ENODEV; 310 } 311 if (ports > (256 / SNDRV_RAWMIDI_DEVICES)) 312 ports = 256 / SNDRV_RAWMIDI_DEVICES; 313 314 mutex_lock(®ister_mutex); 315 client = synths[card->number]; 316 if (client == NULL) { 317 newclient = 1; 318 client = kzalloc(sizeof(*client), GFP_KERNEL); 319 if (client == NULL) { 320 mutex_unlock(®ister_mutex); 321 kfree(info); 322 return -ENOMEM; 323 } 324 client->seq_client = 325 snd_seq_create_kernel_client( 326 card, 0, "%s", card->shortname[0] ? 327 (const char *)card->shortname : "External MIDI"); 328 if (client->seq_client < 0) { 329 kfree(client); 330 mutex_unlock(®ister_mutex); 331 kfree(info); 332 return -ENOMEM; 333 } 334 } 335 336 msynth = kcalloc(ports, sizeof(struct seq_midisynth), GFP_KERNEL); 337 port = kmalloc(sizeof(*port), GFP_KERNEL); 338 if (msynth == NULL || port == NULL) 339 goto __nomem; 340 341 for (p = 0; p < ports; p++) { 342 ms = &msynth[p]; 343 344 if (snd_seq_midisynth_new(ms, card, device, p) < 0) 345 goto __nomem; 346 347 /* declare port */ 348 memset(port, 0, sizeof(*port)); 349 port->addr.client = client->seq_client; 350 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p; 351 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; 352 memset(info, 0, sizeof(*info)); 353 info->device = device; 354 if (p < output_count) 355 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 356 else 357 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 358 info->subdevice = p; 359 if (snd_rawmidi_info_select(card, info) >= 0) 360 strcpy(port->name, info->subname); 361 if (! port->name[0]) { 362 if (info->name[0]) { 363 if (ports > 1) 364 snprintf(port->name, sizeof(port->name), "%s-%u", info->name, p); 365 else 366 snprintf(port->name, sizeof(port->name), "%s", info->name); 367 } else { 368 /* last resort */ 369 if (ports > 1) 370 sprintf(port->name, "MIDI %d-%d-%u", card->number, device, p); 371 else 372 sprintf(port->name, "MIDI %d-%d", card->number, device); 373 } 374 } 375 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count) 376 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 377 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count) 378 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 379 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) && 380 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX) 381 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 382 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC 383 | SNDRV_SEQ_PORT_TYPE_HARDWARE 384 | SNDRV_SEQ_PORT_TYPE_PORT; 385 port->midi_channels = 16; 386 memset(&pcallbacks, 0, sizeof(pcallbacks)); 387 pcallbacks.owner = THIS_MODULE; 388 pcallbacks.private_data = ms; 389 pcallbacks.subscribe = midisynth_subscribe; 390 pcallbacks.unsubscribe = midisynth_unsubscribe; 391 pcallbacks.use = midisynth_use; 392 pcallbacks.unuse = midisynth_unuse; 393 pcallbacks.event_input = event_process_midi; 394 port->kernel = &pcallbacks; 395 if (rmidi->ops && rmidi->ops->get_port_info) 396 rmidi->ops->get_port_info(rmidi, p, port); 397 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0) 398 goto __nomem; 399 ms->seq_client = client->seq_client; 400 ms->seq_port = port->addr.port; 401 } 402 client->ports_per_device[device] = ports; 403 client->ports[device] = msynth; 404 client->num_ports++; 405 if (newclient) 406 synths[card->number] = client; 407 mutex_unlock(®ister_mutex); 408 kfree(info); 409 kfree(port); 410 return 0; /* success */ 411 412 __nomem: 413 if (msynth != NULL) { 414 for (p = 0; p < ports; p++) 415 snd_seq_midisynth_delete(&msynth[p]); 416 kfree(msynth); 417 } 418 if (newclient) { 419 snd_seq_delete_kernel_client(client->seq_client); 420 kfree(client); 421 } 422 kfree(info); 423 kfree(port); 424 mutex_unlock(®ister_mutex); 425 return -ENOMEM; 426 } 427 428 /* release midi synth port */ 429 static int 430 snd_seq_midisynth_unregister_port(struct snd_seq_device *dev) 431 { 432 struct seq_midisynth_client *client; 433 struct seq_midisynth *msynth; 434 struct snd_card *card = dev->card; 435 int device = dev->device, p, ports; 436 437 mutex_lock(®ister_mutex); 438 client = synths[card->number]; 439 if (client == NULL || client->ports[device] == NULL) { 440 mutex_unlock(®ister_mutex); 441 return -ENODEV; 442 } 443 ports = client->ports_per_device[device]; 444 client->ports_per_device[device] = 0; 445 msynth = client->ports[device]; 446 client->ports[device] = NULL; 447 for (p = 0; p < ports; p++) 448 snd_seq_midisynth_delete(&msynth[p]); 449 kfree(msynth); 450 client->num_ports--; 451 if (client->num_ports <= 0) { 452 snd_seq_delete_kernel_client(client->seq_client); 453 synths[card->number] = NULL; 454 kfree(client); 455 } 456 mutex_unlock(®ister_mutex); 457 return 0; 458 } 459 460 461 static int __init alsa_seq_midi_init(void) 462 { 463 static struct snd_seq_dev_ops ops = { 464 snd_seq_midisynth_register_port, 465 snd_seq_midisynth_unregister_port, 466 }; 467 memset(&synths, 0, sizeof(synths)); 468 snd_seq_autoload_lock(); 469 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0); 470 snd_seq_autoload_unlock(); 471 return 0; 472 } 473 474 static void __exit alsa_seq_midi_exit(void) 475 { 476 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH); 477 } 478 479 module_init(alsa_seq_midi_init) 480 module_exit(alsa_seq_midi_exit) 481