sound/isa/wavefront/wavefront_midi.c

   1 /*
   2  * Copyright (C) by Paul Barton-Davis 1998-1999
   3  *
   4  * This file is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
   5  * Version 2 (June 1991). See the "COPYING" file distributed with this
   6  * software for more info.
   7  */
   8
   9 /* The low level driver for the WaveFront ICS2115 MIDI interface(s)
  10  *
  11  * Note that there is also an MPU-401 emulation (actually, a UART-401
  12  * emulation) on the CS4232 on the Tropez and Tropez Plus. This code
  13  * has nothing to do with that interface at all.
  14  *
  15  * The interface is essentially just a UART-401, but is has the
  16  * interesting property of supporting what Turtle Beach called
  17  * "Virtual MIDI" mode. In this mode, there are effectively *two*
  18  * MIDI buses accessible via the interface, one that is routed
  19  * solely to/from the external WaveFront synthesizer and the other
  20  * corresponding to the pin/socket connector used to link external
  21  * MIDI devices to the board.
  22  *
  23  * This driver fully supports this mode, allowing two distinct MIDI
  24  * busses to be used completely independently, giving 32 channels of
  25  * MIDI routing, 16 to the WaveFront synth and 16 to the external MIDI
  26  * bus. The devices are named /dev/snd/midiCnD0 and /dev/snd/midiCnD1,
  27  * where `n' is the card number. Note that the device numbers may be
  28  * something other than 0 and 1 if the CS4232 UART/MPU-401 interface
  29  * is enabled.
  30  *
  31  * Switching between the two is accomplished externally by the driver
  32  * using the two otherwise unused MIDI bytes. See the code for more details.
  33  *
  34  * NOTE: VIRTUAL MIDI MODE IS ON BY DEFAULT (see lowlevel/isa/wavefront.c)
  35  *
  36  * The main reason to turn off Virtual MIDI mode is when you want to
  37  * tightly couple the WaveFront synth with an external MIDI
  38  * device. You won't be able to distinguish the source of any MIDI
  39  * data except via SysEx ID, but thats probably OK, since for the most
  40  * part, the WaveFront won't be sending any MIDI data at all.
  41  *
  42  * The main reason to turn on Virtual MIDI Mode is to provide two
  43  * completely independent 16-channel MIDI buses, one to the
  44  * WaveFront and one to any external MIDI devices. Given the 32
  45  * voice nature of the WaveFront, its pretty easy to find a use
  46  * for all 16 channels driving just that synth.
  47  *
  48  */
  49
  50 #include <asm/io.h>
  51 #include <linux/init.h>
  52 #include <linux/time.h>
  53 #include <linux/wait.h>
  54 #include <sound/core.h>
  55 #include <sound/snd_wavefront.h>
  56
  57 static inline int
  58 wf_mpu_status (snd_wavefront_midi_t *midi)
  59
  60 {
  61         return inb (midi->mpu_status_port);
  62 }
  63
  64 static inline int
  65 input_avail (snd_wavefront_midi_t *midi)
  66
  67 {
  68         return !(wf_mpu_status(midi) & INPUT_AVAIL);
  69 }
  70
  71 static inline int
  72 output_ready (snd_wavefront_midi_t *midi)
  73
  74 {
  75         return !(wf_mpu_status(midi) & OUTPUT_READY);
  76 }
  77
  78 static inline int
  79 read_data (snd_wavefront_midi_t *midi)
  80
  81 {
  82         return inb (midi->mpu_data_port);
  83 }
  84
  85 static inline void
  86 write_data (snd_wavefront_midi_t *midi, unsigned char byte)
  87
  88 {
  89         outb (byte, midi->mpu_data_port);
  90 }
  91
  92 static snd_wavefront_midi_t *
  93 get_wavefront_midi (struct snd_rawmidi_substream *substream)
  94
  95 {
  96         struct snd_card *card;
  97         snd_wavefront_card_t *acard;
  98
  99         if (substream == NULL || substream->rmidi == NULL)
 100                 return NULL;
 101
 102         card = substream->rmidi->card;
 103
 104         if (card == NULL)
 105                 return NULL;
 106
 107         if (card->private_data == NULL)
 108                 return NULL;
 109
 110         acard = card->private_data;
 111
 112         return &acard->wavefront.midi;
 113 }
 114
 115 static void snd_wavefront_midi_output_write(snd_wavefront_card_t *card)
 116 {
 117         snd_wavefront_midi_t *midi = &card->wavefront.midi;
 118         snd_wavefront_mpu_id  mpu;
 119         unsigned long flags;
 120         unsigned char midi_byte;
 121         int max = 256, mask = 1;
 122         int timeout;
 123
 124         /* Its not OK to try to change the status of "virtuality" of
 125            the MIDI interface while we're outputting stuff.  See
 126            snd_wavefront_midi_{enable,disable}_virtual () for the
 127            other half of this.
 128
 129            The first loop attempts to flush any data from the
 130            current output device, and then the second
 131            emits the switch byte (if necessary), and starts
 132            outputting data for the output device currently in use.
 133         */
 134
 135         if (midi->substream_output[midi->output_mpu] == NULL) {
 136                 goto __second;
 137         }
 138
 139         while (max > 0) {
 140
 141                 /* XXX fix me - no hard timing loops allowed! */
 142
 143                 for (timeout = 30000; timeout > 0; timeout--) {
 144                         if (output_ready (midi))
 145                                 break;
 146                 }
 147
 148                 spin_lock_irqsave (&midi->virtual, flags);
 149                 if ((midi->mode[midi->output_mpu] & MPU401_MODE_OUTPUT) == 0) {
 150                         spin_unlock_irqrestore (&midi->virtual, flags);
 151                         goto __second;
 152                 }
 153                 if (output_ready (midi)) {
 154                         if (snd_rawmidi_transmit(midi->substream_output[midi->output_mpu], &midi_byte, 1) == 1) {
 155                                 if (!midi->isvirtual ||
 156                                         (midi_byte != WF_INTERNAL_SWITCH &&
 157                                          midi_byte != WF_EXTERNAL_SWITCH))
 158                                         write_data(midi, midi_byte);
 159                                 max--;
 160                         } else {
 161                                 if (midi->istimer) {
 162                                         if (--midi->istimer <= 0)
 163                                                 del_timer(&midi->timer);
 164                                 }
 165                                 midi->mode[midi->output_mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
 166                                 spin_unlock_irqrestore (&midi->virtual, flags);
 167                                 goto __second;
 168                         }
 169                 } else {
 170                         spin_unlock_irqrestore (&midi->virtual, flags);
 171                         return;
 172                 }
 173                 spin_unlock_irqrestore (&midi->virtual, flags);
 174         }
 175
 176       __second:
 177
 178         if (midi->substream_output[!midi->output_mpu] == NULL) {
 179                 return;
 180         }
 181
 182         while (max > 0) {
 183
 184                 /* XXX fix me - no hard timing loops allowed! */
 185
 186                 for (timeout = 30000; timeout > 0; timeout--) {
 187                         if (output_ready (midi))
 188                                 break;
 189                 }
 190
 191                 spin_lock_irqsave (&midi->virtual, flags);
 192                 if (!midi->isvirtual)
 193                         mask = 0;
 194                 mpu = midi->output_mpu ^ mask;
 195                 mask = 0;       /* don't invert the value from now */
 196                 if ((midi->mode[mpu] & MPU401_MODE_OUTPUT) == 0) {
 197                         spin_unlock_irqrestore (&midi->virtual, flags);
 198                         return;
 199                 }
 200                 if (snd_rawmidi_transmit_empty(midi->substream_output[mpu]))
 201                         goto __timer;
 202                 if (output_ready (midi)) {
 203                         if (mpu != midi->output_mpu) {
 204                                 write_data(midi, mpu == internal_mpu ?
 205                                                         WF_INTERNAL_SWITCH :
 206                                                         WF_EXTERNAL_SWITCH);
 207                                 midi->output_mpu = mpu;
 208                         } else if (snd_rawmidi_transmit(midi->substream_output[mpu], &midi_byte, 1) == 1) {
 209                                 if (!midi->isvirtual ||
 210                                         (midi_byte != WF_INTERNAL_SWITCH &&
 211                                          midi_byte != WF_EXTERNAL_SWITCH))
 212                                         write_data(midi, midi_byte);
 213                                 max--;
 214                         } else {
 215                               __timer:
 216                                 if (midi->istimer) {
 217                                         if (--midi->istimer <= 0)
 218                                                 del_timer(&midi->timer);
 219                                 }
 220                                 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
 221                                 spin_unlock_irqrestore (&midi->virtual, flags);
 222                                 return;
 223                         }
 224                 } else {
 225                         spin_unlock_irqrestore (&midi->virtual, flags);
 226                         return;
 227                 }
 228                 spin_unlock_irqrestore (&midi->virtual, flags);
 229         }
 230 }
 231
 232 static int snd_wavefront_midi_input_open(struct snd_rawmidi_substream *substream)
 233 {
 234         unsigned long flags;
 235         snd_wavefront_midi_t *midi;
 236         snd_wavefront_mpu_id mpu;
 237
 238         if (snd_BUG_ON(!substream || !substream->rmidi))
 239                 return -ENXIO;
 240         if (snd_BUG_ON(!substream->rmidi->private_data))
 241                 return -ENXIO;
 242
 243         mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
 244
 245         if ((midi = get_wavefront_midi (substream)) == NULL)
 246                 return -EIO;
 247
 248         spin_lock_irqsave (&midi->open, flags);
 249         midi->mode[mpu] |= MPU401_MODE_INPUT;
 250         midi->substream_input[mpu] = substream;
 251         spin_unlock_irqrestore (&midi->open, flags);
 252
 253         return 0;
 254 }
 255
 256 static int snd_wavefront_midi_output_open(struct snd_rawmidi_substream *substream)
 257 {
 258         unsigned long flags;
 259         snd_wavefront_midi_t *midi;
 260         snd_wavefront_mpu_id mpu;
 261
 262         if (snd_BUG_ON(!substream || !substream->rmidi))
 263                 return -ENXIO;
 264         if (snd_BUG_ON(!substream->rmidi->private_data))
 265                 return -ENXIO;
 266
 267         mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
 268
 269         if ((midi = get_wavefront_midi (substream)) == NULL)
 270                 return -EIO;
 271
 272         spin_lock_irqsave (&midi->open, flags);
 273         midi->mode[mpu] |= MPU401_MODE_OUTPUT;
 274         midi->substream_output[mpu] = substream;
 275         spin_unlock_irqrestore (&midi->open, flags);
 276
 277         return 0;
 278 }
 279
 280 static int snd_wavefront_midi_input_close(struct snd_rawmidi_substream *substream)
 281 {
 282         unsigned long flags;
 283         snd_wavefront_midi_t *midi;
 284         snd_wavefront_mpu_id mpu;
 285
 286         if (snd_BUG_ON(!substream || !substream->rmidi))
 287                 return -ENXIO;
 288         if (snd_BUG_ON(!substream->rmidi->private_data))
 289                 return -ENXIO;
 290
 291         mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
 292
 293         if ((midi = get_wavefront_midi (substream)) == NULL)
 294                 return -EIO;
 295
 296         spin_lock_irqsave (&midi->open, flags);
 297         midi->mode[mpu] &= ~MPU401_MODE_INPUT;
 298         spin_unlock_irqrestore (&midi->open, flags);
 299
 300         return 0;
 301 }
 302
 303 static int snd_wavefront_midi_output_close(struct snd_rawmidi_substream *substream)
 304 {
 305         unsigned long flags;
 306         snd_wavefront_midi_t *midi;
 307         snd_wavefront_mpu_id mpu;
 308
 309         if (snd_BUG_ON(!substream || !substream->rmidi))
 310                 return -ENXIO;
 311         if (snd_BUG_ON(!substream->rmidi->private_data))
 312                 return -ENXIO;
 313
 314         mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
 315
 316         if ((midi = get_wavefront_midi (substream)) == NULL)
 317                 return -EIO;
 318
 319         spin_lock_irqsave (&midi->open, flags);
 320         midi->mode[mpu] &= ~MPU401_MODE_OUTPUT;
 321         spin_unlock_irqrestore (&midi->open, flags);
 322         return 0;
 323 }
 324
 325 static void snd_wavefront_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
 326 {
 327         unsigned long flags;
 328         snd_wavefront_midi_t *midi;
 329         snd_wavefront_mpu_id mpu;
 330
 331         if (substream == NULL || substream->rmidi == NULL)
 332                 return;
 333
 334         if (substream->rmidi->private_data == NULL)
 335                 return;
 336
 337         mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
 338
 339         if ((midi = get_wavefront_midi (substream)) == NULL) {
 340                 return;
 341         }
 342
 343         spin_lock_irqsave (&midi->virtual, flags);
 344         if (up) {
 345                 midi->mode[mpu] |= MPU401_MODE_INPUT_TRIGGER;
 346         } else {
 347                 midi->mode[mpu] &= ~MPU401_MODE_INPUT_TRIGGER;
 348         }
 349         spin_unlock_irqrestore (&midi->virtual, flags);
 350 }
 351
 352 static void snd_wavefront_midi_output_timer(unsigned long data)
 353 {
 354         snd_wavefront_card_t *card = (snd_wavefront_card_t *)data;
 355         snd_wavefront_midi_t *midi = &card->wavefront.midi;
 356         unsigned long flags;
 357
 358         spin_lock_irqsave (&midi->virtual, flags);
 359         midi->timer.expires = 1 + jiffies;
 360         add_timer(&midi->timer);
 361         spin_unlock_irqrestore (&midi->virtual, flags);
 362         snd_wavefront_midi_output_write(card);
 363 }
 364
 365 static void snd_wavefront_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
 366 {
 367         unsigned long flags;
 368         snd_wavefront_midi_t *midi;
 369         snd_wavefront_mpu_id mpu;
 370
 371         if (substream == NULL || substream->rmidi == NULL)
 372                 return;
 373
 374         if (substream->rmidi->private_data == NULL)
 375                 return;
 376
 377         mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
 378
 379         if ((midi = get_wavefront_midi (substream)) == NULL) {
 380                 return;
 381         }
 382
 383         spin_lock_irqsave (&midi->virtual, flags);
 384         if (up) {
 385                 if ((midi->mode[mpu] & MPU401_MODE_OUTPUT_TRIGGER) == 0) {
 386                         if (!midi->istimer) {
 387                                 init_timer(&midi->timer);
 388                                 midi->timer.function = snd_wavefront_midi_output_timer;
 389                                 midi->timer.data = (unsigned long) substream->rmidi->card->private_data;
 390                                 midi->timer.expires = 1 + jiffies;
 391                                 add_timer(&midi->timer);
 392                         }
 393                         midi->istimer++;
 394                         midi->mode[mpu] |= MPU401_MODE_OUTPUT_TRIGGER;
 395                 }
 396         } else {
 397                 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
 398         }
 399         spin_unlock_irqrestore (&midi->virtual, flags);
 400
 401         if (up)
 402                 snd_wavefront_midi_output_write((snd_wavefront_card_t *)substream->rmidi->card->private_data);
 403 }
 404
 405 void
 406 snd_wavefront_midi_interrupt (snd_wavefront_card_t *card)
 407
 408 {
 409         unsigned long flags;
 410         snd_wavefront_midi_t *midi;
 411         static struct snd_rawmidi_substream *substream = NULL;
 412         static int mpu = external_mpu;
 413         int max = 128;
 414         unsigned char byte;
 415
 416         midi = &card->wavefront.midi;
 417
 418         if (!input_avail (midi)) { /* not for us */
 419                 snd_wavefront_midi_output_write(card);
 420                 return;
 421         }
 422
 423         spin_lock_irqsave (&midi->virtual, flags);
 424         while (--max) {
 425
 426                 if (input_avail (midi)) {
 427                         byte = read_data (midi);
 428
 429                         if (midi->isvirtual) {
 430                                 if (byte == WF_EXTERNAL_SWITCH) {
 431                                         substream = midi->substream_input[external_mpu];
 432                                         mpu = external_mpu;
 433                                 } else if (byte == WF_INTERNAL_SWITCH) {
 434                                         substream = midi->substream_output[internal_mpu];
 435                                         mpu = internal_mpu;
 436                                 } /* else just leave it as it is */
 437                         } else {
 438                                 substream = midi->substream_input[internal_mpu];
 439                                 mpu = internal_mpu;
 440                         }
 441
 442                         if (substream == NULL) {
 443                                 continue;
 444                         }
 445
 446                         if (midi->mode[mpu] & MPU401_MODE_INPUT_TRIGGER) {
 447                                 snd_rawmidi_receive(substream, &byte, 1);
 448                         }
 449                 } else {
 450                         break;
 451                 }
 452         }
 453         spin_unlock_irqrestore (&midi->virtual, flags);
 454
 455         snd_wavefront_midi_output_write(card);
 456 }
 457
 458 void
 459 snd_wavefront_midi_enable_virtual (snd_wavefront_card_t *card)
 460
 461 {
 462         unsigned long flags;
 463
 464         spin_lock_irqsave (&card->wavefront.midi.virtual, flags);
 465         card->wavefront.midi.isvirtual = 1;
 466         card->wavefront.midi.output_mpu = internal_mpu;
 467         card->wavefront.midi.input_mpu = internal_mpu;
 468         spin_unlock_irqrestore (&card->wavefront.midi.virtual, flags);
 469 }
 470
 471 void
 472 snd_wavefront_midi_disable_virtual (snd_wavefront_card_t *card)
 473
 474 {
 475         unsigned long flags;
 476
 477         spin_lock_irqsave (&card->wavefront.midi.virtual, flags);
 478         // snd_wavefront_midi_input_close (card->ics2115_external_rmidi);
 479         // snd_wavefront_midi_output_close (card->ics2115_external_rmidi);
 480         card->wavefront.midi.isvirtual = 0;
 481         spin_unlock_irqrestore (&card->wavefront.midi.virtual, flags);
 482 }
 483
 484 int
 485 snd_wavefront_midi_start (snd_wavefront_card_t *card)
 486
 487 {
 488         int ok, i;
 489         unsigned char rbuf[4], wbuf[4];
 490         snd_wavefront_t *dev;
 491         snd_wavefront_midi_t *midi;
 492
 493         dev = &card->wavefront;
 494         midi = &dev->midi;
 495
 496         /* The ICS2115 MPU-401 interface doesn't do anything
 497            until its set into UART mode.
 498         */
 499
 500         /* XXX fix me - no hard timing loops allowed! */
 501
 502         for (i = 0; i < 30000 && !output_ready (midi); i++);
 503
 504         if (!output_ready (midi)) {
 505                 snd_printk ("MIDI interface not ready for command\n");
 506                 return -1;
 507         }
 508
 509         /* Any interrupts received from now on
 510            are owned by the MIDI side of things.
 511         */
 512
 513         dev->interrupts_are_midi = 1;
 514
 515         outb (UART_MODE_ON, midi->mpu_command_port);
 516
 517         for (ok = 0, i = 50000; i > 0 && !ok; i--) {
 518                 if (input_avail (midi)) {
 519                         if (read_data (midi) == MPU_ACK) {
 520                                 ok = 1;
 521                                 break;
 522                         }
 523                 }
 524         }
 525
 526         if (!ok) {
 527                 snd_printk ("cannot set UART mode for MIDI interface");
 528                 dev->interrupts_are_midi = 0;
 529                 return -1;
 530         }
 531
 532         /* Route external MIDI to WaveFront synth (by default) */
 533
 534         if (snd_wavefront_cmd (dev, WFC_MISYNTH_ON, rbuf, wbuf)) {
 535                 snd_printk ("can't enable MIDI-IN-2-synth routing.\n");
 536                 /* XXX error ? */
 537         }
 538
 539         /* Turn on Virtual MIDI, but first *always* turn it off,
 540            since otherwise consecutive reloads of the driver will
 541            never cause the hardware to generate the initial "internal" or
 542            "external" source bytes in the MIDI data stream. This
 543            is pretty important, since the internal hardware generally will
 544            be used to generate none or very little MIDI output, and
 545            thus the only source of MIDI data is actually external. Without
 546            the switch bytes, the driver will think it all comes from
 547            the internal interface. Duh.
 548         */
 549
 550         if (snd_wavefront_cmd (dev, WFC_VMIDI_OFF, rbuf, wbuf)) {
 551                 snd_printk ("virtual MIDI mode not disabled\n");
 552                 return 0; /* We're OK, but missing the external MIDI dev */
 553         }
 554
 555         snd_wavefront_midi_enable_virtual (card);
 556
 557         if (snd_wavefront_cmd (dev, WFC_VMIDI_ON, rbuf, wbuf)) {
 558                 snd_printk ("cannot enable virtual MIDI mode.\n");
 559                 snd_wavefront_midi_disable_virtual (card);
 560         }
 561         return 0;
 562 }
 563
 564 struct snd_rawmidi_ops snd_wavefront_midi_output =
 565 {
 566         .open =         snd_wavefront_midi_output_open,
 567         .close =        snd_wavefront_midi_output_close,
 568         .trigger =      snd_wavefront_midi_output_trigger,
 569 };
 570
 571 struct snd_rawmidi_ops snd_wavefront_midi_input =
 572 {
 573         .open =         snd_wavefront_midi_input_open,
 574         .close =        snd_wavefront_midi_input_close,
 575         .trigger =      snd_wavefront_midi_input_trigger,
 576 };
 577