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[zen-stable.git] / sound / isa / wavefront / wavefront_midi.c
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1 /*
2 * Copyright (C) by Paul Barton-Davis 1998-1999
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 */
9 /* The low level driver for the WaveFront ICS2115 MIDI interface(s)
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.
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.
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.
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.
34 * NOTE: VIRTUAL MIDI MODE IS ON BY DEFAULT (see lowlevel/isa/wavefront.c)
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.
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.
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>
57 static inline int
58 wf_mpu_status (snd_wavefront_midi_t *midi)
61 return inb (midi->mpu_status_port);
64 static inline int
65 input_avail (snd_wavefront_midi_t *midi)
68 return !(wf_mpu_status(midi) & INPUT_AVAIL);
71 static inline int
72 output_ready (snd_wavefront_midi_t *midi)
75 return !(wf_mpu_status(midi) & OUTPUT_READY);
78 static inline int
79 read_data (snd_wavefront_midi_t *midi)
82 return inb (midi->mpu_data_port);
85 static inline void
86 write_data (snd_wavefront_midi_t *midi, unsigned char byte)
89 outb (byte, midi->mpu_data_port);
92 static snd_wavefront_midi_t *
93 get_wavefront_midi (struct snd_rawmidi_substream *substream)
96 struct snd_card *card;
97 snd_wavefront_card_t *acard;
99 if (substream == NULL || substream->rmidi == NULL)
100 return NULL;
102 card = substream->rmidi->card;
104 if (card == NULL)
105 return NULL;
107 if (card->private_data == NULL)
108 return NULL;
110 acard = card->private_data;
112 return &acard->wavefront.midi;
115 static void snd_wavefront_midi_output_write(snd_wavefront_card_t *card)
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;
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.
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.
135 if (midi->substream_output[midi->output_mpu] == NULL) {
136 goto __second;
139 while (max > 0) {
141 /* XXX fix me - no hard timing loops allowed! */
143 for (timeout = 30000; timeout > 0; timeout--) {
144 if (output_ready (midi))
145 break;
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;
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);
165 midi->mode[midi->output_mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
166 spin_unlock_irqrestore (&midi->virtual, flags);
167 goto __second;
169 } else {
170 spin_unlock_irqrestore (&midi->virtual, flags);
171 return;
173 spin_unlock_irqrestore (&midi->virtual, flags);
176 __second:
178 if (midi->substream_output[!midi->output_mpu] == NULL) {
179 return;
182 while (max > 0) {
184 /* XXX fix me - no hard timing loops allowed! */
186 for (timeout = 30000; timeout > 0; timeout--) {
187 if (output_ready (midi))
188 break;
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;
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);
220 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
221 spin_unlock_irqrestore (&midi->virtual, flags);
222 return;
224 } else {
225 spin_unlock_irqrestore (&midi->virtual, flags);
226 return;
228 spin_unlock_irqrestore (&midi->virtual, flags);
232 static int snd_wavefront_midi_input_open(struct snd_rawmidi_substream *substream)
234 unsigned long flags;
235 snd_wavefront_midi_t *midi;
236 snd_wavefront_mpu_id mpu;
238 if (snd_BUG_ON(!substream || !substream->rmidi))
239 return -ENXIO;
240 if (snd_BUG_ON(!substream->rmidi->private_data))
241 return -ENXIO;
243 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
245 if ((midi = get_wavefront_midi (substream)) == NULL)
246 return -EIO;
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);
253 return 0;
256 static int snd_wavefront_midi_output_open(struct snd_rawmidi_substream *substream)
258 unsigned long flags;
259 snd_wavefront_midi_t *midi;
260 snd_wavefront_mpu_id mpu;
262 if (snd_BUG_ON(!substream || !substream->rmidi))
263 return -ENXIO;
264 if (snd_BUG_ON(!substream->rmidi->private_data))
265 return -ENXIO;
267 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
269 if ((midi = get_wavefront_midi (substream)) == NULL)
270 return -EIO;
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);
277 return 0;
280 static int snd_wavefront_midi_input_close(struct snd_rawmidi_substream *substream)
282 unsigned long flags;
283 snd_wavefront_midi_t *midi;
284 snd_wavefront_mpu_id mpu;
286 if (snd_BUG_ON(!substream || !substream->rmidi))
287 return -ENXIO;
288 if (snd_BUG_ON(!substream->rmidi->private_data))
289 return -ENXIO;
291 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
293 if ((midi = get_wavefront_midi (substream)) == NULL)
294 return -EIO;
296 spin_lock_irqsave (&midi->open, flags);
297 midi->mode[mpu] &= ~MPU401_MODE_INPUT;
298 spin_unlock_irqrestore (&midi->open, flags);
300 return 0;
303 static int snd_wavefront_midi_output_close(struct snd_rawmidi_substream *substream)
305 unsigned long flags;
306 snd_wavefront_midi_t *midi;
307 snd_wavefront_mpu_id mpu;
309 if (snd_BUG_ON(!substream || !substream->rmidi))
310 return -ENXIO;
311 if (snd_BUG_ON(!substream->rmidi->private_data))
312 return -ENXIO;
314 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
316 if ((midi = get_wavefront_midi (substream)) == NULL)
317 return -EIO;
319 spin_lock_irqsave (&midi->open, flags);
320 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT;
321 spin_unlock_irqrestore (&midi->open, flags);
322 return 0;
325 static void snd_wavefront_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
327 unsigned long flags;
328 snd_wavefront_midi_t *midi;
329 snd_wavefront_mpu_id mpu;
331 if (substream == NULL || substream->rmidi == NULL)
332 return;
334 if (substream->rmidi->private_data == NULL)
335 return;
337 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
339 if ((midi = get_wavefront_midi (substream)) == NULL) {
340 return;
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;
349 spin_unlock_irqrestore (&midi->virtual, flags);
352 static void snd_wavefront_midi_output_timer(unsigned long data)
354 snd_wavefront_card_t *card = (snd_wavefront_card_t *)data;
355 snd_wavefront_midi_t *midi = &card->wavefront.midi;
356 unsigned long flags;
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);
365 static void snd_wavefront_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
367 unsigned long flags;
368 snd_wavefront_midi_t *midi;
369 snd_wavefront_mpu_id mpu;
371 if (substream == NULL || substream->rmidi == NULL)
372 return;
374 if (substream->rmidi->private_data == NULL)
375 return;
377 mpu = *((snd_wavefront_mpu_id *) substream->rmidi->private_data);
379 if ((midi = get_wavefront_midi (substream)) == NULL) {
380 return;
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);
393 midi->istimer++;
394 midi->mode[mpu] |= MPU401_MODE_OUTPUT_TRIGGER;
396 } else {
397 midi->mode[mpu] &= ~MPU401_MODE_OUTPUT_TRIGGER;
399 spin_unlock_irqrestore (&midi->virtual, flags);
401 if (up)
402 snd_wavefront_midi_output_write((snd_wavefront_card_t *)substream->rmidi->card->private_data);
405 void
406 snd_wavefront_midi_interrupt (snd_wavefront_card_t *card)
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;
416 midi = &card->wavefront.midi;
418 if (!input_avail (midi)) { /* not for us */
419 snd_wavefront_midi_output_write(card);
420 return;
423 spin_lock_irqsave (&midi->virtual, flags);
424 while (--max) {
426 if (input_avail (midi)) {
427 byte = read_data (midi);
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;
442 if (substream == NULL) {
443 continue;
446 if (midi->mode[mpu] & MPU401_MODE_INPUT_TRIGGER) {
447 snd_rawmidi_receive(substream, &byte, 1);
449 } else {
450 break;
453 spin_unlock_irqrestore (&midi->virtual, flags);
455 snd_wavefront_midi_output_write(card);
458 void
459 snd_wavefront_midi_enable_virtual (snd_wavefront_card_t *card)
462 unsigned long flags;
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);
471 void
472 snd_wavefront_midi_disable_virtual (snd_wavefront_card_t *card)
475 unsigned long flags;
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);
484 int __devinit
485 snd_wavefront_midi_start (snd_wavefront_card_t *card)
488 int ok, i;
489 unsigned char rbuf[4], wbuf[4];
490 snd_wavefront_t *dev;
491 snd_wavefront_midi_t *midi;
493 dev = &card->wavefront;
494 midi = &dev->midi;
496 /* The ICS2115 MPU-401 interface doesn't do anything
497 until its set into UART mode.
500 /* XXX fix me - no hard timing loops allowed! */
502 for (i = 0; i < 30000 && !output_ready (midi); i++);
504 if (!output_ready (midi)) {
505 snd_printk ("MIDI interface not ready for command\n");
506 return -1;
509 /* Any interrupts received from now on
510 are owned by the MIDI side of things.
513 dev->interrupts_are_midi = 1;
515 outb (UART_MODE_ON, midi->mpu_command_port);
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;
526 if (!ok) {
527 snd_printk ("cannot set UART mode for MIDI interface");
528 dev->interrupts_are_midi = 0;
529 return -1;
532 /* Route external MIDI to WaveFront synth (by default) */
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 ? */
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.
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 */
555 snd_wavefront_midi_enable_virtual (card);
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);
561 return 0;
564 struct snd_rawmidi_ops snd_wavefront_midi_output =
566 .open = snd_wavefront_midi_output_open,
567 .close = snd_wavefront_midi_output_close,
568 .trigger = snd_wavefront_midi_output_trigger,
571 struct snd_rawmidi_ops snd_wavefront_midi_input =
573 .open = snd_wavefront_midi_input_open,
574 .close = snd_wavefront_midi_input_close,
575 .trigger = snd_wavefront_midi_input_trigger,