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(struct timer_list
*t
)
174 struct snd_mpu401
*mpu
= from_timer(mpu
, t
, timer
);
177 spin_lock_irqsave(&mpu
->timer_lock
, flags
);
178 /*mpu->mode |= MPU401_MODE_TIMER;*/
179 mod_timer(&mpu
->timer
, 1 + jiffies
);
180 spin_unlock_irqrestore(&mpu
->timer_lock
, flags
);
182 _snd_mpu401_uart_interrupt(mpu
);
186 * initialize the timer callback if not programmed yet
188 static void snd_mpu401_uart_add_timer (struct snd_mpu401
*mpu
, int input
)
192 spin_lock_irqsave (&mpu
->timer_lock
, flags
);
193 if (mpu
->timer_invoked
== 0) {
194 timer_setup(&mpu
->timer
, snd_mpu401_uart_timer
, 0);
195 mod_timer(&mpu
->timer
, 1 + jiffies
);
197 mpu
->timer_invoked
|= input
? MPU401_MODE_INPUT_TIMER
:
198 MPU401_MODE_OUTPUT_TIMER
;
199 spin_unlock_irqrestore (&mpu
->timer_lock
, flags
);
203 * remove the timer callback if still active
205 static void snd_mpu401_uart_remove_timer (struct snd_mpu401
*mpu
, int input
)
209 spin_lock_irqsave (&mpu
->timer_lock
, flags
);
210 if (mpu
->timer_invoked
) {
211 mpu
->timer_invoked
&= input
? ~MPU401_MODE_INPUT_TIMER
:
212 ~MPU401_MODE_OUTPUT_TIMER
;
213 if (! mpu
->timer_invoked
)
214 del_timer(&mpu
->timer
);
216 spin_unlock_irqrestore (&mpu
->timer_lock
, flags
);
220 * send a UART command
221 * return zero if successful, non-zero for some errors
224 static int snd_mpu401_uart_cmd(struct snd_mpu401
* mpu
, unsigned char cmd
,
230 spin_lock_irqsave(&mpu
->input_lock
, flags
);
231 if (mpu
->hardware
!= MPU401_HW_TRID4DWAVE
) {
232 mpu
->write(mpu
, 0x00, MPU401D(mpu
));
233 /*snd_mpu401_uart_clear_rx(mpu);*/
235 /* ok. standard MPU-401 initialization */
236 if (mpu
->hardware
!= MPU401_HW_SB
) {
237 for (timeout
= 1000; timeout
> 0 &&
238 !snd_mpu401_output_ready(mpu
); timeout
--)
240 #ifdef CONFIG_SND_DEBUG
242 snd_printk(KERN_ERR
"cmd: tx timeout (status = 0x%x)\n",
243 mpu
->read(mpu
, MPU401C(mpu
)));
246 mpu
->write(mpu
, cmd
, MPU401C(mpu
));
247 if (ack
&& !(mpu
->info_flags
& MPU401_INFO_NO_ACK
)) {
250 while (!ok
&& timeout
-- > 0) {
251 if (snd_mpu401_input_avail(mpu
)) {
252 if (mpu
->read(mpu
, MPU401D(mpu
)) == MPU401_ACK
)
256 if (!ok
&& mpu
->read(mpu
, MPU401D(mpu
)) == MPU401_ACK
)
260 spin_unlock_irqrestore(&mpu
->input_lock
, flags
);
262 snd_printk(KERN_ERR
"cmd: 0x%x failed at 0x%lx "
263 "(status = 0x%x, data = 0x%x)\n", cmd
, mpu
->port
,
264 mpu
->read(mpu
, MPU401C(mpu
)),
265 mpu
->read(mpu
, MPU401D(mpu
)));
271 static int snd_mpu401_do_reset(struct snd_mpu401
*mpu
)
273 if (snd_mpu401_uart_cmd(mpu
, MPU401_RESET
, 1))
275 if (snd_mpu401_uart_cmd(mpu
, MPU401_ENTER_UART
, 0))
281 * input/output open/close - protected by open_mutex in rawmidi.c
283 static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream
*substream
)
285 struct snd_mpu401
*mpu
;
288 mpu
= substream
->rmidi
->private_data
;
289 if (mpu
->open_input
&& (err
= mpu
->open_input(mpu
)) < 0)
291 if (! test_bit(MPU401_MODE_BIT_OUTPUT
, &mpu
->mode
)) {
292 if (snd_mpu401_do_reset(mpu
) < 0)
295 mpu
->substream_input
= substream
;
296 set_bit(MPU401_MODE_BIT_INPUT
, &mpu
->mode
);
300 if (mpu
->open_input
&& mpu
->close_input
)
301 mpu
->close_input(mpu
);
305 static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream
*substream
)
307 struct snd_mpu401
*mpu
;
310 mpu
= substream
->rmidi
->private_data
;
311 if (mpu
->open_output
&& (err
= mpu
->open_output(mpu
)) < 0)
313 if (! test_bit(MPU401_MODE_BIT_INPUT
, &mpu
->mode
)) {
314 if (snd_mpu401_do_reset(mpu
) < 0)
317 mpu
->substream_output
= substream
;
318 set_bit(MPU401_MODE_BIT_OUTPUT
, &mpu
->mode
);
322 if (mpu
->open_output
&& mpu
->close_output
)
323 mpu
->close_output(mpu
);
327 static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream
*substream
)
329 struct snd_mpu401
*mpu
;
332 mpu
= substream
->rmidi
->private_data
;
333 clear_bit(MPU401_MODE_BIT_INPUT
, &mpu
->mode
);
334 mpu
->substream_input
= NULL
;
335 if (! test_bit(MPU401_MODE_BIT_OUTPUT
, &mpu
->mode
))
336 err
= snd_mpu401_uart_cmd(mpu
, MPU401_RESET
, 0);
337 if (mpu
->close_input
)
338 mpu
->close_input(mpu
);
344 static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream
*substream
)
346 struct snd_mpu401
*mpu
;
349 mpu
= substream
->rmidi
->private_data
;
350 clear_bit(MPU401_MODE_BIT_OUTPUT
, &mpu
->mode
);
351 mpu
->substream_output
= NULL
;
352 if (! test_bit(MPU401_MODE_BIT_INPUT
, &mpu
->mode
))
353 err
= snd_mpu401_uart_cmd(mpu
, MPU401_RESET
, 0);
354 if (mpu
->close_output
)
355 mpu
->close_output(mpu
);
362 * trigger input callback
365 snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream
*substream
, int up
)
368 struct snd_mpu401
*mpu
;
371 mpu
= substream
->rmidi
->private_data
;
373 if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER
,
375 /* first time - flush FIFO */
377 mpu
->read(mpu
, MPU401D(mpu
));
378 if (mpu
->info_flags
& MPU401_INFO_USE_TIMER
)
379 snd_mpu401_uart_add_timer(mpu
, 1);
382 /* read data in advance */
383 spin_lock_irqsave(&mpu
->input_lock
, flags
);
384 snd_mpu401_uart_input_read(mpu
);
385 spin_unlock_irqrestore(&mpu
->input_lock
, flags
);
387 if (mpu
->info_flags
& MPU401_INFO_USE_TIMER
)
388 snd_mpu401_uart_remove_timer(mpu
, 1);
389 clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER
, &mpu
->mode
);
395 * transfer input pending data
396 * call with input_lock spinlock held
398 static void snd_mpu401_uart_input_read(struct snd_mpu401
* mpu
)
404 if (! snd_mpu401_input_avail(mpu
))
405 break; /* input not available */
406 byte
= mpu
->read(mpu
, MPU401D(mpu
));
407 if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER
, &mpu
->mode
))
408 snd_rawmidi_receive(mpu
->substream_input
, &byte
, 1);
415 * AudioDrive ES1688 - 12 bytes
416 * S3 SonicVibes - 8 bytes
417 * SoundBlaster AWE 64 - 2 bytes (ugly hardware)
421 * write output pending bytes
422 * call with output_lock spinlock held
424 static void snd_mpu401_uart_output_write(struct snd_mpu401
* mpu
)
430 if (snd_rawmidi_transmit_peek(mpu
->substream_output
,
433 * Try twice because there is hardware that insists on
434 * setting the output busy bit after each write.
436 if (!snd_mpu401_output_ready(mpu
) &&
437 !snd_mpu401_output_ready(mpu
))
438 break; /* Tx FIFO full - try again later */
439 mpu
->write(mpu
, byte
, MPU401D(mpu
));
440 snd_rawmidi_transmit_ack(mpu
->substream_output
, 1);
442 snd_mpu401_uart_remove_timer (mpu
, 0);
443 break; /* no other data - leave the tx loop */
449 * output trigger callback
452 snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream
*substream
, int up
)
455 struct snd_mpu401
*mpu
;
457 mpu
= substream
->rmidi
->private_data
;
459 set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER
, &mpu
->mode
);
461 /* try to add the timer at each output trigger,
462 * since the output timer might have been removed in
463 * snd_mpu401_uart_output_write().
465 if (! (mpu
->info_flags
& MPU401_INFO_TX_IRQ
))
466 snd_mpu401_uart_add_timer(mpu
, 0);
468 /* output pending data */
469 spin_lock_irqsave(&mpu
->output_lock
, flags
);
470 snd_mpu401_uart_output_write(mpu
);
471 spin_unlock_irqrestore(&mpu
->output_lock
, flags
);
473 if (! (mpu
->info_flags
& MPU401_INFO_TX_IRQ
))
474 snd_mpu401_uart_remove_timer(mpu
, 0);
475 clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER
, &mpu
->mode
);
483 static const struct snd_rawmidi_ops snd_mpu401_uart_output
=
485 .open
= snd_mpu401_uart_output_open
,
486 .close
= snd_mpu401_uart_output_close
,
487 .trigger
= snd_mpu401_uart_output_trigger
,
490 static const struct snd_rawmidi_ops snd_mpu401_uart_input
=
492 .open
= snd_mpu401_uart_input_open
,
493 .close
= snd_mpu401_uart_input_close
,
494 .trigger
= snd_mpu401_uart_input_trigger
,
497 static void snd_mpu401_uart_free(struct snd_rawmidi
*rmidi
)
499 struct snd_mpu401
*mpu
= rmidi
->private_data
;
501 free_irq(mpu
->irq
, (void *) mpu
);
502 release_and_free_resource(mpu
->res
);
507 * snd_mpu401_uart_new - create an MPU401-UART instance
508 * @card: the card instance
509 * @device: the device index, zero-based
510 * @hardware: the hardware type, MPU401_HW_XXXX
511 * @port: the base address of MPU401 port
512 * @info_flags: bitflags MPU401_INFO_XXX
513 * @irq: the ISA irq number, -1 if not to be allocated
514 * @rrawmidi: the pointer to store the new rawmidi instance
516 * Creates a new MPU-401 instance.
518 * Note that the rawmidi instance is returned on the rrawmidi argument,
519 * not the mpu401 instance itself. To access to the mpu401 instance,
520 * cast from rawmidi->private_data (with struct snd_mpu401 magic-cast).
522 * Return: Zero if successful, or a negative error code.
524 int snd_mpu401_uart_new(struct snd_card
*card
, int device
,
525 unsigned short hardware
,
527 unsigned int info_flags
,
529 struct snd_rawmidi
** rrawmidi
)
531 struct snd_mpu401
*mpu
;
532 struct snd_rawmidi
*rmidi
;
533 int in_enable
, out_enable
;
538 if (! (info_flags
& (MPU401_INFO_INPUT
| MPU401_INFO_OUTPUT
)))
539 info_flags
|= MPU401_INFO_INPUT
| MPU401_INFO_OUTPUT
;
540 in_enable
= (info_flags
& MPU401_INFO_INPUT
) ? 1 : 0;
541 out_enable
= (info_flags
& MPU401_INFO_OUTPUT
) ? 1 : 0;
542 if ((err
= snd_rawmidi_new(card
, "MPU-401U", device
,
543 out_enable
, in_enable
, &rmidi
)) < 0)
545 mpu
= kzalloc(sizeof(*mpu
), GFP_KERNEL
);
550 rmidi
->private_data
= mpu
;
551 rmidi
->private_free
= snd_mpu401_uart_free
;
552 spin_lock_init(&mpu
->input_lock
);
553 spin_lock_init(&mpu
->output_lock
);
554 spin_lock_init(&mpu
->timer_lock
);
555 mpu
->hardware
= hardware
;
557 if (! (info_flags
& MPU401_INFO_INTEGRATED
)) {
558 int res_size
= hardware
== MPU401_HW_PC98II
? 4 : 2;
559 mpu
->res
= request_region(port
, res_size
, "MPU401 UART");
561 snd_printk(KERN_ERR
"mpu401_uart: "
562 "unable to grab port 0x%lx size %d\n",
568 if (info_flags
& MPU401_INFO_MMIO
) {
569 mpu
->write
= mpu401_write_mmio
;
570 mpu
->read
= mpu401_read_mmio
;
572 mpu
->write
= mpu401_write_port
;
573 mpu
->read
= mpu401_read_port
;
576 if (hardware
== MPU401_HW_PC98II
)
577 mpu
->cport
= port
+ 2;
579 mpu
->cport
= port
+ 1;
581 if (request_irq(irq
, snd_mpu401_uart_interrupt
, 0,
582 "MPU401 UART", (void *) mpu
)) {
583 snd_printk(KERN_ERR
"mpu401_uart: "
584 "unable to grab IRQ %d\n", irq
);
589 if (irq
< 0 && !(info_flags
& MPU401_INFO_IRQ_HOOK
))
590 info_flags
|= MPU401_INFO_USE_TIMER
;
591 mpu
->info_flags
= info_flags
;
593 if (card
->shortname
[0])
594 snprintf(rmidi
->name
, sizeof(rmidi
->name
), "%s MIDI",
597 sprintf(rmidi
->name
, "MPU-401 MIDI %d-%d",card
->number
, device
);
599 snd_rawmidi_set_ops(rmidi
, SNDRV_RAWMIDI_STREAM_OUTPUT
,
600 &snd_mpu401_uart_output
);
601 rmidi
->info_flags
|= SNDRV_RAWMIDI_INFO_OUTPUT
;
604 snd_rawmidi_set_ops(rmidi
, SNDRV_RAWMIDI_STREAM_INPUT
,
605 &snd_mpu401_uart_input
);
606 rmidi
->info_flags
|= SNDRV_RAWMIDI_INFO_INPUT
;
608 rmidi
->info_flags
|= SNDRV_RAWMIDI_INFO_DUPLEX
;
615 snd_device_free(card
, rmidi
);
619 EXPORT_SYMBOL(snd_mpu401_uart_new
);
625 static int __init
alsa_mpu401_uart_init(void)
630 static void __exit
alsa_mpu401_uart_exit(void)
634 module_init(alsa_mpu401_uart_init
)
635 module_exit(alsa_mpu401_uart_exit
)