2 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3 * Routines for control of MPU-401 in UART mode
5 * MPU-401 supports UART mode which is not capable generate transmit
6 * interrupts thus output is done via polling. Without interrupt,
7 * input is done also via polling. Do not expect good performance.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 * Added support for different kind of hardware I/O. Build in choices
26 * are port and mmio. For other kind of I/O, set mpu->read and
27 * mpu->write to your own I/O functions.
32 #include <linux/delay.h>
33 #include <linux/init.h>
34 #include <linux/slab.h>
35 #include <linux/ioport.h>
36 #include <linux/module.h>
37 #include <linux/interrupt.h>
38 #include <linux/errno.h>
39 #include <sound/core.h>
40 #include <sound/mpu401.h>
42 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
43 MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
44 MODULE_LICENSE("GPL");
46 static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu);
47 static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu);
53 #define snd_mpu401_input_avail(mpu) \
54 (!(mpu->read(mpu, MPU401C(mpu)) & MPU401_RX_EMPTY))
55 #define snd_mpu401_output_ready(mpu) \
56 (!(mpu->read(mpu, MPU401C(mpu)) & MPU401_TX_FULL))
58 /* Build in lowlevel io */
59 static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data,
65 static unsigned char mpu401_read_port(struct snd_mpu401 *mpu,
71 static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data,
74 writeb(data, (void __iomem *)addr);
77 static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu,
80 return readb((void __iomem *)addr);
84 static void snd_mpu401_uart_clear_rx(struct snd_mpu401 *mpu)
87 for (; timeout > 0 && snd_mpu401_input_avail(mpu); timeout--)
88 mpu->read(mpu, MPU401D(mpu));
89 #ifdef CONFIG_SND_DEBUG
91 snd_printk(KERN_ERR "cmd: clear rx timeout (status = 0x%x)\n",
92 mpu->read(mpu, MPU401C(mpu)));
96 static void uart_interrupt_tx(struct snd_mpu401 *mpu)
100 if (test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode) &&
101 test_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode)) {
102 spin_lock_irqsave(&mpu->output_lock, flags);
103 snd_mpu401_uart_output_write(mpu);
104 spin_unlock_irqrestore(&mpu->output_lock, flags);
108 static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
112 if (mpu->info_flags & MPU401_INFO_INPUT) {
113 spin_lock_irqsave(&mpu->input_lock, flags);
114 if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
115 snd_mpu401_uart_input_read(mpu);
117 snd_mpu401_uart_clear_rx(mpu);
118 spin_unlock_irqrestore(&mpu->input_lock, flags);
120 if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
121 /* ok. for better Tx performance try do some output
122 when input is done */
123 uart_interrupt_tx(mpu);
127 * snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
128 * @irq: the irq number
129 * @dev_id: mpu401 instance
131 * Processes the interrupt for MPU401-UART i/o.
133 * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
135 irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id)
137 struct snd_mpu401 *mpu = dev_id;
141 _snd_mpu401_uart_interrupt(mpu);
145 EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
148 * snd_mpu401_uart_interrupt_tx - generic MPU401-UART transmit irq handler
149 * @irq: the irq number
150 * @dev_id: mpu401 instance
152 * Processes the interrupt for MPU401-UART output.
154 * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
156 irqreturn_t snd_mpu401_uart_interrupt_tx(int irq, void *dev_id)
158 struct snd_mpu401 *mpu = dev_id;
162 uart_interrupt_tx(mpu);
166 EXPORT_SYMBOL(snd_mpu401_uart_interrupt_tx);
170 * reprogram the timer and call the interrupt job
172 static void snd_mpu401_uart_timer(unsigned long data)
174 struct snd_mpu401 *mpu = (struct snd_mpu401 *)data;
177 spin_lock_irqsave(&mpu->timer_lock, flags);
178 /*mpu->mode |= MPU401_MODE_TIMER;*/
179 mpu->timer.expires = 1 + jiffies;
180 add_timer(&mpu->timer);
181 spin_unlock_irqrestore(&mpu->timer_lock, flags);
183 _snd_mpu401_uart_interrupt(mpu);
187 * initialize the timer callback if not programmed yet
189 static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input)
193 spin_lock_irqsave (&mpu->timer_lock, flags);
194 if (mpu->timer_invoked == 0) {
195 init_timer(&mpu->timer);
196 mpu->timer.data = (unsigned long)mpu;
197 mpu->timer.function = snd_mpu401_uart_timer;
198 mpu->timer.expires = 1 + jiffies;
199 add_timer(&mpu->timer);
201 mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER :
202 MPU401_MODE_OUTPUT_TIMER;
203 spin_unlock_irqrestore (&mpu->timer_lock, flags);
207 * remove the timer callback if still active
209 static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
213 spin_lock_irqsave (&mpu->timer_lock, flags);
214 if (mpu->timer_invoked) {
215 mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER :
216 ~MPU401_MODE_OUTPUT_TIMER;
217 if (! mpu->timer_invoked)
218 del_timer(&mpu->timer);
220 spin_unlock_irqrestore (&mpu->timer_lock, flags);
224 * send a UART command
225 * return zero if successful, non-zero for some errors
228 static int snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd,
234 spin_lock_irqsave(&mpu->input_lock, flags);
235 if (mpu->hardware != MPU401_HW_TRID4DWAVE) {
236 mpu->write(mpu, 0x00, MPU401D(mpu));
237 /*snd_mpu401_uart_clear_rx(mpu);*/
239 /* ok. standard MPU-401 initialization */
240 if (mpu->hardware != MPU401_HW_SB) {
241 for (timeout = 1000; timeout > 0 &&
242 !snd_mpu401_output_ready(mpu); timeout--)
244 #ifdef CONFIG_SND_DEBUG
246 snd_printk(KERN_ERR "cmd: tx timeout (status = 0x%x)\n",
247 mpu->read(mpu, MPU401C(mpu)));
250 mpu->write(mpu, cmd, MPU401C(mpu));
251 if (ack && !(mpu->info_flags & MPU401_INFO_NO_ACK)) {
254 while (!ok && timeout-- > 0) {
255 if (snd_mpu401_input_avail(mpu)) {
256 if (mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
260 if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
264 spin_unlock_irqrestore(&mpu->input_lock, flags);
266 snd_printk(KERN_ERR "cmd: 0x%x failed at 0x%lx "
267 "(status = 0x%x, data = 0x%x)\n", cmd, mpu->port,
268 mpu->read(mpu, MPU401C(mpu)),
269 mpu->read(mpu, MPU401D(mpu)));
275 static int snd_mpu401_do_reset(struct snd_mpu401 *mpu)
277 if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1))
279 if (snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 0))
285 * input/output open/close - protected by open_mutex in rawmidi.c
287 static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream *substream)
289 struct snd_mpu401 *mpu;
292 mpu = substream->rmidi->private_data;
293 if (mpu->open_input && (err = mpu->open_input(mpu)) < 0)
295 if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
296 if (snd_mpu401_do_reset(mpu) < 0)
299 mpu->substream_input = substream;
300 set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
304 if (mpu->open_input && mpu->close_input)
305 mpu->close_input(mpu);
309 static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
311 struct snd_mpu401 *mpu;
314 mpu = substream->rmidi->private_data;
315 if (mpu->open_output && (err = mpu->open_output(mpu)) < 0)
317 if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
318 if (snd_mpu401_do_reset(mpu) < 0)
321 mpu->substream_output = substream;
322 set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
326 if (mpu->open_output && mpu->close_output)
327 mpu->close_output(mpu);
331 static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream *substream)
333 struct snd_mpu401 *mpu;
336 mpu = substream->rmidi->private_data;
337 clear_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
338 mpu->substream_input = NULL;
339 if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode))
340 err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
341 if (mpu->close_input)
342 mpu->close_input(mpu);
348 static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream *substream)
350 struct snd_mpu401 *mpu;
353 mpu = substream->rmidi->private_data;
354 clear_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
355 mpu->substream_output = NULL;
356 if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
357 err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
358 if (mpu->close_output)
359 mpu->close_output(mpu);
366 * trigger input callback
369 snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
372 struct snd_mpu401 *mpu;
375 mpu = substream->rmidi->private_data;
377 if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER,
379 /* first time - flush FIFO */
381 mpu->read(mpu, MPU401D(mpu));
382 if (mpu->info_flags & MPU401_INFO_USE_TIMER)
383 snd_mpu401_uart_add_timer(mpu, 1);
386 /* read data in advance */
387 spin_lock_irqsave(&mpu->input_lock, flags);
388 snd_mpu401_uart_input_read(mpu);
389 spin_unlock_irqrestore(&mpu->input_lock, flags);
391 if (mpu->info_flags & MPU401_INFO_USE_TIMER)
392 snd_mpu401_uart_remove_timer(mpu, 1);
393 clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
399 * transfer input pending data
400 * call with input_lock spinlock held
402 static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
408 if (! snd_mpu401_input_avail(mpu))
409 break; /* input not available */
410 byte = mpu->read(mpu, MPU401D(mpu));
411 if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
412 snd_rawmidi_receive(mpu->substream_input, &byte, 1);
419 * AudioDrive ES1688 - 12 bytes
420 * S3 SonicVibes - 8 bytes
421 * SoundBlaster AWE 64 - 2 bytes (ugly hardware)
425 * write output pending bytes
426 * call with output_lock spinlock held
428 static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
434 if (snd_rawmidi_transmit_peek(mpu->substream_output,
437 * Try twice because there is hardware that insists on
438 * setting the output busy bit after each write.
440 if (!snd_mpu401_output_ready(mpu) &&
441 !snd_mpu401_output_ready(mpu))
442 break; /* Tx FIFO full - try again later */
443 mpu->write(mpu, byte, MPU401D(mpu));
444 snd_rawmidi_transmit_ack(mpu->substream_output, 1);
446 snd_mpu401_uart_remove_timer (mpu, 0);
447 break; /* no other data - leave the tx loop */
453 * output trigger callback
456 snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
459 struct snd_mpu401 *mpu;
461 mpu = substream->rmidi->private_data;
463 set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
465 /* try to add the timer at each output trigger,
466 * since the output timer might have been removed in
467 * snd_mpu401_uart_output_write().
469 if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
470 snd_mpu401_uart_add_timer(mpu, 0);
472 /* output pending data */
473 spin_lock_irqsave(&mpu->output_lock, flags);
474 snd_mpu401_uart_output_write(mpu);
475 spin_unlock_irqrestore(&mpu->output_lock, flags);
477 if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
478 snd_mpu401_uart_remove_timer(mpu, 0);
479 clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
487 static struct snd_rawmidi_ops snd_mpu401_uart_output =
489 .open = snd_mpu401_uart_output_open,
490 .close = snd_mpu401_uart_output_close,
491 .trigger = snd_mpu401_uart_output_trigger,
494 static struct snd_rawmidi_ops snd_mpu401_uart_input =
496 .open = snd_mpu401_uart_input_open,
497 .close = snd_mpu401_uart_input_close,
498 .trigger = snd_mpu401_uart_input_trigger,
501 static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
503 struct snd_mpu401 *mpu = rmidi->private_data;
505 free_irq(mpu->irq, (void *) mpu);
506 release_and_free_resource(mpu->res);
511 * snd_mpu401_uart_new - create an MPU401-UART instance
512 * @card: the card instance
513 * @device: the device index, zero-based
514 * @hardware: the hardware type, MPU401_HW_XXXX
515 * @port: the base address of MPU401 port
516 * @info_flags: bitflags MPU401_INFO_XXX
517 * @irq: the ISA irq number, -1 if not to be allocated
518 * @rrawmidi: the pointer to store the new rawmidi instance
520 * Creates a new MPU-401 instance.
522 * Note that the rawmidi instance is returned on the rrawmidi argument,
523 * not the mpu401 instance itself. To access to the mpu401 instance,
524 * cast from rawmidi->private_data (with struct snd_mpu401 magic-cast).
526 * Return: Zero if successful, or a negative error code.
528 int snd_mpu401_uart_new(struct snd_card *card, int device,
529 unsigned short hardware,
531 unsigned int info_flags,
533 struct snd_rawmidi ** rrawmidi)
535 struct snd_mpu401 *mpu;
536 struct snd_rawmidi *rmidi;
537 int in_enable, out_enable;
542 if (! (info_flags & (MPU401_INFO_INPUT | MPU401_INFO_OUTPUT)))
543 info_flags |= MPU401_INFO_INPUT | MPU401_INFO_OUTPUT;
544 in_enable = (info_flags & MPU401_INFO_INPUT) ? 1 : 0;
545 out_enable = (info_flags & MPU401_INFO_OUTPUT) ? 1 : 0;
546 if ((err = snd_rawmidi_new(card, "MPU-401U", device,
547 out_enable, in_enable, &rmidi)) < 0)
549 mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
551 snd_printk(KERN_ERR "mpu401_uart: cannot allocate\n");
552 snd_device_free(card, rmidi);
555 rmidi->private_data = mpu;
556 rmidi->private_free = snd_mpu401_uart_free;
557 spin_lock_init(&mpu->input_lock);
558 spin_lock_init(&mpu->output_lock);
559 spin_lock_init(&mpu->timer_lock);
560 mpu->hardware = hardware;
562 if (! (info_flags & MPU401_INFO_INTEGRATED)) {
563 int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
564 mpu->res = request_region(port, res_size, "MPU401 UART");
565 if (mpu->res == NULL) {
566 snd_printk(KERN_ERR "mpu401_uart: "
567 "unable to grab port 0x%lx size %d\n",
569 snd_device_free(card, rmidi);
573 if (info_flags & MPU401_INFO_MMIO) {
574 mpu->write = mpu401_write_mmio;
575 mpu->read = mpu401_read_mmio;
577 mpu->write = mpu401_write_port;
578 mpu->read = mpu401_read_port;
581 if (hardware == MPU401_HW_PC98II)
582 mpu->cport = port + 2;
584 mpu->cport = port + 1;
586 if (request_irq(irq, snd_mpu401_uart_interrupt, 0,
587 "MPU401 UART", (void *) mpu)) {
588 snd_printk(KERN_ERR "mpu401_uart: "
589 "unable to grab IRQ %d\n", irq);
590 snd_device_free(card, rmidi);
594 if (irq < 0 && !(info_flags & MPU401_INFO_IRQ_HOOK))
595 info_flags |= MPU401_INFO_USE_TIMER;
596 mpu->info_flags = info_flags;
598 if (card->shortname[0])
599 snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI",
602 sprintf(rmidi->name, "MPU-401 MIDI %d-%d",card->number, device);
604 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
605 &snd_mpu401_uart_output);
606 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
609 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
610 &snd_mpu401_uart_input);
611 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
613 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
621 EXPORT_SYMBOL(snd_mpu401_uart_new);
627 static int __init alsa_mpu401_uart_init(void)
632 static void __exit alsa_mpu401_uart_exit(void)
636 module_init(alsa_mpu401_uart_init)
637 module_exit(alsa_mpu401_uart_exit)