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; 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 if (!snd_midi_event_encode_byte(msynth->parser, 99 *pbuf++, &ev)) 100 continue; 101 ev.source.port = msynth->seq_port; 102 ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS; 103 snd_seq_kernel_client_dispatch(msynth->seq_client, &ev, 1, 0); 104 /* clear event and reset header */ 105 memset(&ev, 0, sizeof(ev)); 106 } 107 } 108 } 109 110 static int dump_midi(struct snd_rawmidi_substream *substream, const char *buf, int count) 111 { 112 struct snd_rawmidi_runtime *runtime; 113 int tmp; 114 115 if (snd_BUG_ON(!substream || !buf)) 116 return -EINVAL; 117 runtime = substream->runtime; 118 if ((tmp = runtime->avail) < count) { 119 if (printk_ratelimit()) 120 pr_err("ALSA: seq_midi: MIDI output buffer overrun\n"); 121 return -ENOMEM; 122 } 123 if (snd_rawmidi_kernel_write(substream, buf, count) < count) 124 return -EINVAL; 125 return 0; 126 } 127 128 static int event_process_midi(struct snd_seq_event *ev, int direct, 129 void *private_data, int atomic, int hop) 130 { 131 struct seq_midisynth *msynth = private_data; 132 unsigned char msg[10]; /* buffer for constructing midi messages */ 133 struct snd_rawmidi_substream *substream; 134 int len; 135 136 if (snd_BUG_ON(!msynth)) 137 return -EINVAL; 138 substream = msynth->output_rfile.output; 139 if (substream == NULL) 140 return -ENODEV; 141 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */ 142 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) { 143 /* invalid event */ 144 pr_debug("ALSA: seq_midi: invalid sysex event flags = 0x%x\n", ev->flags); 145 return 0; 146 } 147 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream); 148 snd_midi_event_reset_decode(msynth->parser); 149 } else { 150 if (msynth->parser == NULL) 151 return -EIO; 152 len = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev); 153 if (len < 0) 154 return 0; 155 if (dump_midi(substream, msg, len) < 0) 156 snd_midi_event_reset_decode(msynth->parser); 157 } 158 return 0; 159 } 160 161 162 static int snd_seq_midisynth_new(struct seq_midisynth *msynth, 163 struct snd_card *card, 164 int device, 165 int subdevice) 166 { 167 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0) 168 return -ENOMEM; 169 msynth->card = card; 170 msynth->device = device; 171 msynth->subdevice = subdevice; 172 return 0; 173 } 174 175 /* open associated midi device for input */ 176 static int midisynth_subscribe(void *private_data, struct snd_seq_port_subscribe *info) 177 { 178 int err; 179 struct seq_midisynth *msynth = private_data; 180 struct snd_rawmidi_runtime *runtime; 181 struct snd_rawmidi_params params; 182 183 /* open midi port */ 184 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device, 185 msynth->subdevice, 186 SNDRV_RAWMIDI_LFLG_INPUT, 187 &msynth->input_rfile)) < 0) { 188 pr_debug("ALSA: seq_midi: midi input open failed!!!\n"); 189 return err; 190 } 191 runtime = msynth->input_rfile.input->runtime; 192 memset(¶ms, 0, sizeof(params)); 193 params.avail_min = 1; 194 params.buffer_size = input_buffer_size; 195 if ((err = snd_rawmidi_input_params(msynth->input_rfile.input, ¶ms)) < 0) { 196 snd_rawmidi_kernel_release(&msynth->input_rfile); 197 return err; 198 } 199 snd_midi_event_reset_encode(msynth->parser); 200 runtime->event = snd_midi_input_event; 201 runtime->private_data = msynth; 202 snd_rawmidi_kernel_read(msynth->input_rfile.input, NULL, 0); 203 return 0; 204 } 205 206 /* close associated midi device for input */ 207 static int midisynth_unsubscribe(void *private_data, struct snd_seq_port_subscribe *info) 208 { 209 int err; 210 struct seq_midisynth *msynth = private_data; 211 212 if (snd_BUG_ON(!msynth->input_rfile.input)) 213 return -EINVAL; 214 err = snd_rawmidi_kernel_release(&msynth->input_rfile); 215 return err; 216 } 217 218 /* open associated midi device for output */ 219 static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info) 220 { 221 int err; 222 struct seq_midisynth *msynth = private_data; 223 struct snd_rawmidi_params params; 224 225 /* open midi port */ 226 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device, 227 msynth->subdevice, 228 SNDRV_RAWMIDI_LFLG_OUTPUT, 229 &msynth->output_rfile)) < 0) { 230 pr_debug("ALSA: seq_midi: midi output open failed!!!\n"); 231 return err; 232 } 233 memset(¶ms, 0, sizeof(params)); 234 params.avail_min = 1; 235 params.buffer_size = output_buffer_size; 236 params.no_active_sensing = 1; 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; 249 250 if (snd_BUG_ON(!msynth->output_rfile.output)) 251 return -EINVAL; 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(struct seq_midisynth *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 snd_midi_event_free(msynth->parser); 268 } 269 270 /* register new midi synth port */ 271 static int 272 snd_seq_midisynth_probe(struct device *_dev) 273 { 274 struct snd_seq_device *dev = to_seq_dev(_dev); 275 struct seq_midisynth_client *client; 276 struct seq_midisynth *msynth, *ms; 277 struct snd_seq_port_info *port; 278 struct snd_rawmidi_info *info; 279 struct snd_rawmidi *rmidi = dev->private_data; 280 int newclient = 0; 281 unsigned int p, ports; 282 struct snd_seq_port_callback pcallbacks; 283 struct snd_card *card = dev->card; 284 int device = dev->device; 285 unsigned int input_count = 0, output_count = 0; 286 287 if (snd_BUG_ON(!card || device < 0 || device >= SNDRV_RAWMIDI_DEVICES)) 288 return -EINVAL; 289 info = kmalloc(sizeof(*info), GFP_KERNEL); 290 if (! info) 291 return -ENOMEM; 292 info->device = device; 293 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 294 info->subdevice = 0; 295 if (snd_rawmidi_info_select(card, info) >= 0) 296 output_count = info->subdevices_count; 297 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 298 if (snd_rawmidi_info_select(card, info) >= 0) { 299 input_count = info->subdevices_count; 300 } 301 ports = output_count; 302 if (ports < input_count) 303 ports = input_count; 304 if (ports == 0) { 305 kfree(info); 306 return -ENODEV; 307 } 308 if (ports > (256 / SNDRV_RAWMIDI_DEVICES)) 309 ports = 256 / SNDRV_RAWMIDI_DEVICES; 310 311 mutex_lock(®ister_mutex); 312 client = synths[card->number]; 313 if (client == NULL) { 314 newclient = 1; 315 client = kzalloc(sizeof(*client), GFP_KERNEL); 316 if (client == NULL) { 317 mutex_unlock(®ister_mutex); 318 kfree(info); 319 return -ENOMEM; 320 } 321 client->seq_client = 322 snd_seq_create_kernel_client( 323 card, 0, "%s", card->shortname[0] ? 324 (const char *)card->shortname : "External MIDI"); 325 if (client->seq_client < 0) { 326 kfree(client); 327 mutex_unlock(®ister_mutex); 328 kfree(info); 329 return -ENOMEM; 330 } 331 } 332 333 msynth = kcalloc(ports, sizeof(struct seq_midisynth), GFP_KERNEL); 334 port = kmalloc(sizeof(*port), GFP_KERNEL); 335 if (msynth == NULL || port == NULL) 336 goto __nomem; 337 338 for (p = 0; p < ports; p++) { 339 ms = &msynth[p]; 340 341 if (snd_seq_midisynth_new(ms, card, device, p) < 0) 342 goto __nomem; 343 344 /* declare port */ 345 memset(port, 0, sizeof(*port)); 346 port->addr.client = client->seq_client; 347 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p; 348 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; 349 memset(info, 0, sizeof(*info)); 350 info->device = device; 351 if (p < output_count) 352 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT; 353 else 354 info->stream = SNDRV_RAWMIDI_STREAM_INPUT; 355 info->subdevice = p; 356 if (snd_rawmidi_info_select(card, info) >= 0) 357 strcpy(port->name, info->subname); 358 if (! port->name[0]) { 359 if (info->name[0]) { 360 if (ports > 1) 361 snprintf(port->name, sizeof(port->name), "%s-%u", info->name, p); 362 else 363 snprintf(port->name, sizeof(port->name), "%s", info->name); 364 } else { 365 /* last resort */ 366 if (ports > 1) 367 sprintf(port->name, "MIDI %d-%d-%u", card->number, device, p); 368 else 369 sprintf(port->name, "MIDI %d-%d", card->number, device); 370 } 371 } 372 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count) 373 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE; 374 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count) 375 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ; 376 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) && 377 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX) 378 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX; 379 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC 380 | SNDRV_SEQ_PORT_TYPE_HARDWARE 381 | SNDRV_SEQ_PORT_TYPE_PORT; 382 port->midi_channels = 16; 383 memset(&pcallbacks, 0, sizeof(pcallbacks)); 384 pcallbacks.owner = THIS_MODULE; 385 pcallbacks.private_data = ms; 386 pcallbacks.subscribe = midisynth_subscribe; 387 pcallbacks.unsubscribe = midisynth_unsubscribe; 388 pcallbacks.use = midisynth_use; 389 pcallbacks.unuse = midisynth_unuse; 390 pcallbacks.event_input = event_process_midi; 391 port->kernel = &pcallbacks; 392 if (rmidi->ops && rmidi->ops->get_port_info) 393 rmidi->ops->get_port_info(rmidi, p, port); 394 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0) 395 goto __nomem; 396 ms->seq_client = client->seq_client; 397 ms->seq_port = port->addr.port; 398 } 399 client->ports_per_device[device] = ports; 400 client->ports[device] = msynth; 401 client->num_ports++; 402 if (newclient) 403 synths[card->number] = client; 404 mutex_unlock(®ister_mutex); 405 kfree(info); 406 kfree(port); 407 return 0; /* success */ 408 409 __nomem: 410 if (msynth != NULL) { 411 for (p = 0; p < ports; p++) 412 snd_seq_midisynth_delete(&msynth[p]); 413 kfree(msynth); 414 } 415 if (newclient) { 416 snd_seq_delete_kernel_client(client->seq_client); 417 kfree(client); 418 } 419 kfree(info); 420 kfree(port); 421 mutex_unlock(®ister_mutex); 422 return -ENOMEM; 423 } 424 425 /* release midi synth port */ 426 static int 427 snd_seq_midisynth_remove(struct device *_dev) 428 { 429 struct snd_seq_device *dev = to_seq_dev(_dev); 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 static struct snd_seq_driver seq_midisynth_driver = { 459 .driver = { 460 .name = KBUILD_MODNAME, 461 .probe = snd_seq_midisynth_probe, 462 .remove = snd_seq_midisynth_remove, 463 }, 464 .id = SNDRV_SEQ_DEV_ID_MIDISYNTH, 465 .argsize = 0, 466 }; 467 468 module_snd_seq_driver(seq_midisynth_driver); 469