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