1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) by Paul Barton-Davis 1998-1999
4 */
5
6 /* The low level driver for the WaveFront ICS2115 MIDI interface(s)
7 *
8 * Note that there is also an MPU-401 emulation (actually, a UART-401
9 * emulation) on the CS4232 on the Tropez and Tropez Plus. This code
10 * has nothing to do with that interface at all.
11 *
12 * The interface is essentially just a UART-401, but is has the
13 * interesting property of supporting what Turtle Beach called
14 * "Virtual MIDI" mode. In this mode, there are effectively *two*
15 * MIDI buses accessible via the interface, one that is routed
16 * solely to/from the external WaveFront synthesizer and the other
17 * corresponding to the pin/socket connector used to link external
18 * MIDI devices to the board.
19 *
20 * This driver fully supports this mode, allowing two distinct MIDI
21 * busses to be used completely independently, giving 32 channels of
22 * MIDI routing, 16 to the WaveFront synth and 16 to the external MIDI
23 * bus. The devices are named /dev/snd/midiCnD0 and /dev/snd/midiCnD1,
24 * where `n' is the card number. Note that the device numbers may be
25 * something other than 0 and 1 if the CS4232 UART/MPU-401 interface
26 * is enabled.
27 *
28 * Switching between the two is accomplished externally by the driver
29 * using the two otherwise unused MIDI bytes. See the code for more details.
30 *
31 * NOTE: VIRTUAL MIDI MODE IS ON BY DEFAULT (see lowlevel/isa/wavefront.c)
32 *
33 * The main reason to turn off Virtual MIDI mode is when you want to
34 * tightly couple the WaveFront synth with an external MIDI
35 * device. You won't be able to distinguish the source of any MIDI
36 * data except via SysEx ID, but thats probably OK, since for the most
37 * part, the WaveFront won't be sending any MIDI data at all.
38 *
39 * The main reason to turn on Virtual MIDI Mode is to provide two
40 * completely independent 16-channel MIDI buses, one to the
41 * WaveFront and one to any external MIDI devices. Given the 32
42 * voice nature of the WaveFront, its pretty easy to find a use
43 * for all 16 channels driving just that synth.
44 *
45 */
46
47 #include <linux/io.h>
48 #include <linux/init.h>
49 #include <linux/time.h>
50 #include <linux/wait.h>
51 #include <sound/core.h>
52 #include <sound/snd_wavefront.h>
53
54 static inline int
wf_mpu_status(snd_wavefront_midi_t * midi)55 wf_mpu_status (snd_wavefront_midi_t *midi)
56
57 {
58 return inb (midi->mpu_status_port);
59 }
60
61 static inline int
input_avail(snd_wavefront_midi_t * midi)62 input_avail (snd_wavefront_midi_t *midi)
63
64 {
65 return !(wf_mpu_status(midi) & INPUT_AVAIL);
66 }
67
68 static inline int
output_ready(snd_wavefront_midi_t * midi)69 output_ready (snd_wavefront_midi_t *midi)
70
71 {
72 return !(wf_mpu_status(midi) & OUTPUT_READY);
73 }
74
75 static inline int
read_data(snd_wavefront_midi_t * midi)76 read_data (snd_wavefront_midi_t *midi)
77
78 {
79 return inb (midi->mpu_data_port);
80 }
81
82 static inline void
write_data(snd_wavefront_midi_t * midi,unsigned char byte)83 write_data (snd_wavefront_midi_t *midi, unsigned char byte)
84
85 {
86 outb (byte, midi->mpu_data_port);
87 }
88
89 static snd_wavefront_midi_t *
get_wavefront_midi(struct snd_rawmidi_substream * substream)90 get_wavefront_midi (struct snd_rawmidi_substream *substream)
91
92 {
93 struct snd_card *card;
94 snd_wavefront_card_t *acard;
95
96 if (substream == NULL || substream->rmidi == NULL)
97 return NULL;
98
99 card = substream->rmidi->card;
100
101 if (card == NULL)
102 return NULL;
103
104 if (card->private_data == NULL)
105 return NULL;
106
107 acard = card->private_data;
108
109 return &acard->wavefront.midi;
110 }
111
snd_wavefront_midi_output_write(snd_wavefront_card_t * card)112 static void snd_wavefront_midi_output_write(snd_wavefront_card_t *card)
113 {
114 snd_wavefront_midi_t *midi = &card->wavefront.midi;
115 snd_wavefront_mpu_id mpu;
116 unsigned long flags;
117 unsigned char midi_byte;
118 int max = 256, mask = 1;
119 int timeout;
120
121 /* Its not OK to try to change the status of "virtuality" of
122 the MIDI interface while we're outputting stuff. See
123 snd_wavefront_midi_{enable,disable}_virtual () for the
124 other half of this.
125
126 The first loop attempts to flush any data from the
127 current output device, and then the second
128 emits the switch byte (if necessary), and starts
129 outputting data for the output device currently in use.
130 */
131
132 if (midi->substream_output[midi->output_mpu] == NULL) {
133 goto __second;
134 }
135
136 while (max > 0) {
137
138 /* XXX fix me - no hard timing loops allowed! */
139
140 for (timeout = 30000; timeout > 0; timeout--) {
141 if (output_ready (midi))
142 break;
143 }
144
145 spin_lock_irqsave (&midi->virtual, flags);
146 if ((midi->mode[midi->output_mpu] & MPU401_MODE_OUTPUT) == 0) {
147 spin_unlock_irqrestore (&midi->virtual, flags);
148 goto __second;
149 }
150 if (output_ready (midi)) {
151 if (snd_rawmidi_transmit(midi->substream_output[midi->output_mpu], &midi_byte, 1) == 1) {
152 if (!midi->isvirtual ||
153 (midi_byte != WF_INTERNAL_SWITCH &&
154 midi_byte != WF_EXTERNAL_SWITCH))
155 write_data(midi, midi_byte);
156 max--;
157 } else {
158 if (midi->istimer) {
159 if (--midi->istimer <= 0)
160 del_timer(&midi->timer);
161 }
162 midi->mode[midi->output_mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
163 spin_unlock_irqrestore (&midi->virtual, flags);
164 goto __second;
165 }
166 } else {
167 spin_unlock_irqrestore (&midi->virtual, flags);
168 return;
169 }
170 spin_unlock_irqrestore (&midi->virtual, flags);
171 }
172
173 __second:
174
175 if (midi->substream_output[!midi->output_mpu] == NULL) {
176 return;
177 }
178
179 while (max > 0) {
180
181 /* XXX fix me - no hard timing loops allowed! */
182
183 for (timeout = 30000; timeout > 0; timeout--) {
184 if (output_ready (midi))
185 break;
186 }
187
188 spin_lock_irqsave (&midi->virtual, flags);
189 if (!midi->isvirtual)
190 mask = 0;
191 mpu = midi->output_mpu ^ mask;
192 mask = 0; /* don't invert the value from now */
193 if ((midi->mode[mpu] & MPU401_MODE_OUTPUT) == 0) {
194 spin_unlock_irqrestore (&midi->virtual, flags);
195 return;
196 }
197 if (snd_rawmidi_transmit_empty(midi->substream_output[mpu]))
198 goto __timer;
199 if (output_ready (midi)) {
200 if (mpu != midi->output_mpu) {
201 write_data(midi, mpu == internal_mpu ?
202 WF_INTERNAL_SWITCH :
203 WF_EXTERNAL_SWITCH);
204 midi->output_mpu = mpu;
205 } else if (snd_rawmidi_transmit(midi->substream_output[mpu], &midi_byte, 1) == 1) {
206 if (!midi->isvirtual ||
207 (midi_byte != WF_INTERNAL_SWITCH &&
208 midi_byte != WF_EXTERNAL_SWITCH))
209 write_data(midi, midi_byte);
210 max--;
211 } else {
212 __timer:
213 if (midi->istimer) {
214 if (--midi->istimer <= 0)
215 del_timer(&midi->timer);
216 }
217 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
218 spin_unlock_irqrestore (&midi->virtual, flags);
219 return;
220 }
221 } else {
222 spin_unlock_irqrestore (&midi->virtual, flags);
223 return;
224 }
225 spin_unlock_irqrestore (&midi->virtual, flags);
226 }
227 }
228
snd_wavefront_midi_input_open(struct snd_rawmidi_substream * substream)229 static int snd_wavefront_midi_input_open(struct snd_rawmidi_substream *substream)
230 {
231 unsigned long flags;
232 snd_wavefront_midi_t *midi;
233 snd_wavefront_mpu_id mpu;
234
235 if (snd_BUG_ON(!substream || !substream->rmidi))
236 return -ENXIO;
237 if (snd_BUG_ON(!substream->rmidi->private_data))
238 return -ENXIO;
239
240 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
241
242 midi = get_wavefront_midi(substream);
243 if (!midi)
244 return -EIO;
245
246 spin_lock_irqsave (&midi->open, flags);
247 midi->mode[mpu] |= MPU401_MODE_INPUT;
248 midi->substream_input[mpu] = substream;
249 spin_unlock_irqrestore (&midi->open, flags);
250
251 return 0;
252 }
253
snd_wavefront_midi_output_open(struct snd_rawmidi_substream * substream)254 static int snd_wavefront_midi_output_open(struct snd_rawmidi_substream *substream)
255 {
256 unsigned long flags;
257 snd_wavefront_midi_t *midi;
258 snd_wavefront_mpu_id mpu;
259
260 if (snd_BUG_ON(!substream || !substream->rmidi))
261 return -ENXIO;
262 if (snd_BUG_ON(!substream->rmidi->private_data))
263 return -ENXIO;
264
265 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
266
267 midi = get_wavefront_midi(substream);
268 if (!midi)
269 return -EIO;
270
271 spin_lock_irqsave (&midi->open, flags);
272 midi->mode[mpu] |= MPU401_MODE_OUTPUT;
273 midi->substream_output[mpu] = substream;
274 spin_unlock_irqrestore (&midi->open, flags);
275
276 return 0;
277 }
278
snd_wavefront_midi_input_close(struct snd_rawmidi_substream * substream)279 static int snd_wavefront_midi_input_close(struct snd_rawmidi_substream *substream)
280 {
281 unsigned long flags;
282 snd_wavefront_midi_t *midi;
283 snd_wavefront_mpu_id mpu;
284
285 if (snd_BUG_ON(!substream || !substream->rmidi))
286 return -ENXIO;
287 if (snd_BUG_ON(!substream->rmidi->private_data))
288 return -ENXIO;
289
290 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
291
292 midi = get_wavefront_midi(substream);
293 if (!midi)
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
snd_wavefront_midi_output_close(struct snd_rawmidi_substream * substream)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 midi = get_wavefront_midi(substream);
317 if (!midi)
318 return -EIO;
319
320 spin_lock_irqsave (&midi->open, flags);
321 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT;
322 spin_unlock_irqrestore (&midi->open, flags);
323 return 0;
324 }
325
snd_wavefront_midi_input_trigger(struct snd_rawmidi_substream * substream,int up)326 static void snd_wavefront_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
327 {
328 unsigned long flags;
329 snd_wavefront_midi_t *midi;
330 snd_wavefront_mpu_id mpu;
331
332 if (substream == NULL || substream->rmidi == NULL)
333 return;
334
335 if (substream->rmidi->private_data == NULL)
336 return;
337
338 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
339
340 midi = get_wavefront_midi(substream);
341 if (!midi)
342 return;
343
344 spin_lock_irqsave (&midi->virtual, flags);
345 if (up) {
346 midi->mode[mpu] |= MPU401_MODE_INPUT_TRIGGER;
347 } else {
348 midi->mode[mpu] &= ~MPU401_MODE_INPUT_TRIGGER;
349 }
350 spin_unlock_irqrestore (&midi->virtual, flags);
351 }
352
snd_wavefront_midi_output_timer(struct timer_list * t)353 static void snd_wavefront_midi_output_timer(struct timer_list *t)
354 {
355 snd_wavefront_midi_t *midi = from_timer(midi, t, timer);
356 snd_wavefront_card_t *card = midi->timer_card;
357 unsigned long flags;
358
359 spin_lock_irqsave (&midi->virtual, flags);
360 mod_timer(&midi->timer, 1 + jiffies);
361 spin_unlock_irqrestore (&midi->virtual, flags);
362 snd_wavefront_midi_output_write(card);
363 }
364
snd_wavefront_midi_output_trigger(struct snd_rawmidi_substream * substream,int up)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 midi = get_wavefront_midi(substream);
380 if (!midi)
381 return;
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 timer_setup(&midi->timer,
388 snd_wavefront_midi_output_timer,
389 0);
390 mod_timer(&midi->timer, 1 + jiffies);
391 }
392 midi->istimer++;
393 midi->mode[mpu] |= MPU401_MODE_OUTPUT_TRIGGER;
394 }
395 } else {
396 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
397 }
398 spin_unlock_irqrestore (&midi->virtual, flags);
399
400 if (up)
401 snd_wavefront_midi_output_write((snd_wavefront_card_t *)substream->rmidi->card->private_data);
402 }
403
404 void
snd_wavefront_midi_interrupt(snd_wavefront_card_t * card)405 snd_wavefront_midi_interrupt (snd_wavefront_card_t *card)
406
407 {
408 unsigned long flags;
409 snd_wavefront_midi_t *midi;
410 static struct snd_rawmidi_substream *substream = NULL;
411 static int mpu = external_mpu;
412 int max = 128;
413 unsigned char byte;
414
415 midi = &card->wavefront.midi;
416
417 if (!input_avail (midi)) { /* not for us */
418 snd_wavefront_midi_output_write(card);
419 return;
420 }
421
422 spin_lock_irqsave (&midi->virtual, flags);
423 while (--max) {
424
425 if (input_avail (midi)) {
426 byte = read_data (midi);
427
428 if (midi->isvirtual) {
429 if (byte == WF_EXTERNAL_SWITCH) {
430 substream = midi->substream_input[external_mpu];
431 mpu = external_mpu;
432 } else if (byte == WF_INTERNAL_SWITCH) {
433 substream = midi->substream_output[internal_mpu];
434 mpu = internal_mpu;
435 } /* else just leave it as it is */
436 } else {
437 substream = midi->substream_input[internal_mpu];
438 mpu = internal_mpu;
439 }
440
441 if (substream == NULL) {
442 continue;
443 }
444
445 if (midi->mode[mpu] & MPU401_MODE_INPUT_TRIGGER) {
446 snd_rawmidi_receive(substream, &byte, 1);
447 }
448 } else {
449 break;
450 }
451 }
452 spin_unlock_irqrestore (&midi->virtual, flags);
453
454 snd_wavefront_midi_output_write(card);
455 }
456
457 void
snd_wavefront_midi_enable_virtual(snd_wavefront_card_t * card)458 snd_wavefront_midi_enable_virtual (snd_wavefront_card_t *card)
459
460 {
461 unsigned long flags;
462
463 spin_lock_irqsave (&card->wavefront.midi.virtual, flags);
464 card->wavefront.midi.isvirtual = 1;
465 card->wavefront.midi.output_mpu = internal_mpu;
466 card->wavefront.midi.input_mpu = internal_mpu;
467 spin_unlock_irqrestore (&card->wavefront.midi.virtual, flags);
468 }
469
470 void
snd_wavefront_midi_disable_virtual(snd_wavefront_card_t * card)471 snd_wavefront_midi_disable_virtual (snd_wavefront_card_t *card)
472
473 {
474 unsigned long flags;
475
476 spin_lock_irqsave (&card->wavefront.midi.virtual, flags);
477 // snd_wavefront_midi_input_close (card->ics2115_external_rmidi);
478 // snd_wavefront_midi_output_close (card->ics2115_external_rmidi);
479 card->wavefront.midi.isvirtual = 0;
480 spin_unlock_irqrestore (&card->wavefront.midi.virtual, flags);
481 }
482
483 int
snd_wavefront_midi_start(snd_wavefront_card_t * card)484 snd_wavefront_midi_start (snd_wavefront_card_t *card)
485
486 {
487 int ok, i;
488 unsigned char rbuf[4], wbuf[4];
489 snd_wavefront_t *dev;
490 snd_wavefront_midi_t *midi;
491
492 dev = &card->wavefront;
493 midi = &dev->midi;
494
495 /* The ICS2115 MPU-401 interface doesn't do anything
496 until its set into UART mode.
497 */
498
499 /* XXX fix me - no hard timing loops allowed! */
500
501 for (i = 0; i < 30000 && !output_ready (midi); i++);
502
503 if (!output_ready (midi)) {
504 snd_printk ("MIDI interface not ready for command\n");
505 return -1;
506 }
507
508 /* Any interrupts received from now on
509 are owned by the MIDI side of things.
510 */
511
512 dev->interrupts_are_midi = 1;
513
514 outb (UART_MODE_ON, midi->mpu_command_port);
515
516 for (ok = 0, i = 50000; i > 0 && !ok; i--) {
517 if (input_avail (midi)) {
518 if (read_data (midi) == MPU_ACK) {
519 ok = 1;
520 break;
521 }
522 }
523 }
524
525 if (!ok) {
526 snd_printk ("cannot set UART mode for MIDI interface");
527 dev->interrupts_are_midi = 0;
528 return -1;
529 }
530
531 /* Route external MIDI to WaveFront synth (by default) */
532
533 if (snd_wavefront_cmd (dev, WFC_MISYNTH_ON, rbuf, wbuf)) {
534 snd_printk ("can't enable MIDI-IN-2-synth routing.\n");
535 /* XXX error ? */
536 }
537
538 /* Turn on Virtual MIDI, but first *always* turn it off,
539 since otherwise consecutive reloads of the driver will
540 never cause the hardware to generate the initial "internal" or
541 "external" source bytes in the MIDI data stream. This
542 is pretty important, since the internal hardware generally will
543 be used to generate none or very little MIDI output, and
544 thus the only source of MIDI data is actually external. Without
545 the switch bytes, the driver will think it all comes from
546 the internal interface. Duh.
547 */
548
549 if (snd_wavefront_cmd (dev, WFC_VMIDI_OFF, rbuf, wbuf)) {
550 snd_printk ("virtual MIDI mode not disabled\n");
551 return 0; /* We're OK, but missing the external MIDI dev */
552 }
553
554 snd_wavefront_midi_enable_virtual (card);
555
556 if (snd_wavefront_cmd (dev, WFC_VMIDI_ON, rbuf, wbuf)) {
557 snd_printk ("cannot enable virtual MIDI mode.\n");
558 snd_wavefront_midi_disable_virtual (card);
559 }
560 return 0;
561 }
562
563 const struct snd_rawmidi_ops snd_wavefront_midi_output =
564 {
565 .open = snd_wavefront_midi_output_open,
566 .close = snd_wavefront_midi_output_close,
567 .trigger = snd_wavefront_midi_output_trigger,
568 };
569
570 const struct snd_rawmidi_ops snd_wavefront_midi_input =
571 {
572 .open = snd_wavefront_midi_input_open,
573 .close = snd_wavefront_midi_input_close,
574 .trigger = snd_wavefront_midi_input_trigger,
575 };
576
577