sound/core/seq/seq_midi.c

   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(&params, 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, &params)) < 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(&params, 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, &params)) < 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(&register_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(&register_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(&register_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(&register_mutex);
 417         kfree(info);
 418         kfree(port);
 419         return 0;       /* success */
 420
 421       __nomem:
 422         if (msynth != NULL) {
 423                 for (p = 0; p < ports; p++)
 424                         snd_seq_midisynth_delete(&msynth[p]);
 425                 kfree(msynth);
 426         }
 427         if (newclient) {
 428                 snd_seq_delete_kernel_client(client->seq_client);
 429                 kfree(client);
 430         }
 431         kfree(info);
 432         kfree(port);
 433         up(&register_mutex);
 434         return -ENOMEM;
 435 }
 436
 437 /* release midi synth port */
 438 static int
 439 snd_seq_midisynth_unregister_port(snd_seq_device_t *dev)
 440 {
 441         seq_midisynth_client_t *client;
 442         seq_midisynth_t *msynth;
 443         snd_card_t *card = dev->card;
 444         int device = dev->device, p, ports;
 445
 446         down(&register_mutex);
 447         client = synths[card->number];
 448         if (client == NULL || client->ports[device] == NULL) {
 449                 up(&register_mutex);
 450                 return -ENODEV;
 451         }
 452         ports = client->ports_per_device[device];
 453         client->ports_per_device[device] = 0;
 454         msynth = client->ports[device];
 455         client->ports[device] = NULL;
 456         snd_runtime_check(msynth != NULL || ports <= 0, goto __skip);
 457         for (p = 0; p < ports; p++)
 458                 snd_seq_midisynth_delete(&msynth[p]);
 459         kfree(msynth);
 460       __skip:
 461         client->num_ports--;
 462         if (client->num_ports <= 0) {
 463                 snd_seq_delete_kernel_client(client->seq_client);
 464                 synths[card->number] = NULL;
 465                 kfree(client);
 466         }
 467         up(&register_mutex);
 468         return 0;
 469 }
 470
 471
 472 static int __init alsa_seq_midi_init(void)
 473 {
 474         static snd_seq_dev_ops_t ops = {
 475                 snd_seq_midisynth_register_port,
 476                 snd_seq_midisynth_unregister_port,
 477         };
 478         memset(&synths, 0, sizeof(synths));
 479         snd_seq_autoload_lock();
 480         snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0);
 481         snd_seq_autoload_unlock();
 482         return 0;
 483 }
 484
 485 static void __exit alsa_seq_midi_exit(void)
 486 {
 487         snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH);
 488 }
 489
 490 module_init(alsa_seq_midi_init)
 491 module_exit(alsa_seq_midi_exit)