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 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 setup_timer(&mpu->timer, snd_mpu401_uart_timer,
196 mod_timer(&mpu->timer, 1 + jiffies);
198 mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER :
199 MPU401_MODE_OUTPUT_TIMER;
200 spin_unlock_irqrestore (&mpu->timer_lock, flags);
204 * remove the timer callback if still active
206 static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
210 spin_lock_irqsave (&mpu->timer_lock, flags);
211 if (mpu->timer_invoked) {
212 mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER :
213 ~MPU401_MODE_OUTPUT_TIMER;
214 if (! mpu->timer_invoked)
215 del_timer(&mpu->timer);
217 spin_unlock_irqrestore (&mpu->timer_lock, flags);
221 * send a UART command
222 * return zero if successful, non-zero for some errors
225 static int snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd,
231 spin_lock_irqsave(&mpu->input_lock, flags);
232 if (mpu->hardware != MPU401_HW_TRID4DWAVE) {
233 mpu->write(mpu, 0x00, MPU401D(mpu));
234 /*snd_mpu401_uart_clear_rx(mpu);*/
236 /* ok. standard MPU-401 initialization */
237 if (mpu->hardware != MPU401_HW_SB) {
238 for (timeout = 1000; timeout > 0 &&
239 !snd_mpu401_output_ready(mpu); timeout--)
241 #ifdef CONFIG_SND_DEBUG
243 snd_printk(KERN_ERR "cmd: tx timeout (status = 0x%x)\n",
244 mpu->read(mpu, MPU401C(mpu)));
247 mpu->write(mpu, cmd, MPU401C(mpu));
248 if (ack && !(mpu->info_flags & MPU401_INFO_NO_ACK)) {
251 while (!ok && timeout-- > 0) {
252 if (snd_mpu401_input_avail(mpu)) {
253 if (mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
257 if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
261 spin_unlock_irqrestore(&mpu->input_lock, flags);
263 snd_printk(KERN_ERR "cmd: 0x%x failed at 0x%lx "
264 "(status = 0x%x, data = 0x%x)\n", cmd, mpu->port,
265 mpu->read(mpu, MPU401C(mpu)),
266 mpu->read(mpu, MPU401D(mpu)));
272 static int snd_mpu401_do_reset(struct snd_mpu401 *mpu)
274 if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1))
276 if (snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 0))
282 * input/output open/close - protected by open_mutex in rawmidi.c
284 static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream *substream)
286 struct snd_mpu401 *mpu;
289 mpu = substream->rmidi->private_data;
290 if (mpu->open_input && (err = mpu->open_input(mpu)) < 0)
292 if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
293 if (snd_mpu401_do_reset(mpu) < 0)
296 mpu->substream_input = substream;
297 set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
301 if (mpu->open_input && mpu->close_input)
302 mpu->close_input(mpu);
306 static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
308 struct snd_mpu401 *mpu;
311 mpu = substream->rmidi->private_data;
312 if (mpu->open_output && (err = mpu->open_output(mpu)) < 0)
314 if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
315 if (snd_mpu401_do_reset(mpu) < 0)
318 mpu->substream_output = substream;
319 set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
323 if (mpu->open_output && mpu->close_output)
324 mpu->close_output(mpu);
328 static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream *substream)
330 struct snd_mpu401 *mpu;
333 mpu = substream->rmidi->private_data;
334 clear_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
335 mpu->substream_input = NULL;
336 if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode))
337 err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
338 if (mpu->close_input)
339 mpu->close_input(mpu);
345 static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream *substream)
347 struct snd_mpu401 *mpu;
350 mpu = substream->rmidi->private_data;
351 clear_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
352 mpu->substream_output = NULL;
353 if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
354 err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
355 if (mpu->close_output)
356 mpu->close_output(mpu);
363 * trigger input callback
366 snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
369 struct snd_mpu401 *mpu;
372 mpu = substream->rmidi->private_data;
374 if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER,
376 /* first time - flush FIFO */
378 mpu->read(mpu, MPU401D(mpu));
379 if (mpu->info_flags & MPU401_INFO_USE_TIMER)
380 snd_mpu401_uart_add_timer(mpu, 1);
383 /* read data in advance */
384 spin_lock_irqsave(&mpu->input_lock, flags);
385 snd_mpu401_uart_input_read(mpu);
386 spin_unlock_irqrestore(&mpu->input_lock, flags);
388 if (mpu->info_flags & MPU401_INFO_USE_TIMER)
389 snd_mpu401_uart_remove_timer(mpu, 1);
390 clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
396 * transfer input pending data
397 * call with input_lock spinlock held
399 static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
405 if (! snd_mpu401_input_avail(mpu))
406 break; /* input not available */
407 byte = mpu->read(mpu, MPU401D(mpu));
408 if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
409 snd_rawmidi_receive(mpu->substream_input, &byte, 1);
416 * AudioDrive ES1688 - 12 bytes
417 * S3 SonicVibes - 8 bytes
418 * SoundBlaster AWE 64 - 2 bytes (ugly hardware)
422 * write output pending bytes
423 * call with output_lock spinlock held
425 static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
431 if (snd_rawmidi_transmit_peek(mpu->substream_output,
434 * Try twice because there is hardware that insists on
435 * setting the output busy bit after each write.
437 if (!snd_mpu401_output_ready(mpu) &&
438 !snd_mpu401_output_ready(mpu))
439 break; /* Tx FIFO full - try again later */
440 mpu->write(mpu, byte, MPU401D(mpu));
441 snd_rawmidi_transmit_ack(mpu->substream_output, 1);
443 snd_mpu401_uart_remove_timer (mpu, 0);
444 break; /* no other data - leave the tx loop */
450 * output trigger callback
453 snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
456 struct snd_mpu401 *mpu;
458 mpu = substream->rmidi->private_data;
460 set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
462 /* try to add the timer at each output trigger,
463 * since the output timer might have been removed in
464 * snd_mpu401_uart_output_write().
466 if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
467 snd_mpu401_uart_add_timer(mpu, 0);
469 /* output pending data */
470 spin_lock_irqsave(&mpu->output_lock, flags);
471 snd_mpu401_uart_output_write(mpu);
472 spin_unlock_irqrestore(&mpu->output_lock, flags);
474 if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
475 snd_mpu401_uart_remove_timer(mpu, 0);
476 clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
484 static const struct snd_rawmidi_ops snd_mpu401_uart_output =
486 .open = snd_mpu401_uart_output_open,
487 .close = snd_mpu401_uart_output_close,
488 .trigger = snd_mpu401_uart_output_trigger,
491 static const struct snd_rawmidi_ops snd_mpu401_uart_input =
493 .open = snd_mpu401_uart_input_open,
494 .close = snd_mpu401_uart_input_close,
495 .trigger = snd_mpu401_uart_input_trigger,
498 static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
500 struct snd_mpu401 *mpu = rmidi->private_data;
502 free_irq(mpu->irq, (void *) mpu);
503 release_and_free_resource(mpu->res);
508 * snd_mpu401_uart_new - create an MPU401-UART instance
509 * @card: the card instance
510 * @device: the device index, zero-based
511 * @hardware: the hardware type, MPU401_HW_XXXX
512 * @port: the base address of MPU401 port
513 * @info_flags: bitflags MPU401_INFO_XXX
514 * @irq: the ISA irq number, -1 if not to be allocated
515 * @rrawmidi: the pointer to store the new rawmidi instance
517 * Creates a new MPU-401 instance.
519 * Note that the rawmidi instance is returned on the rrawmidi argument,
520 * not the mpu401 instance itself. To access to the mpu401 instance,
521 * cast from rawmidi->private_data (with struct snd_mpu401 magic-cast).
523 * Return: Zero if successful, or a negative error code.
525 int snd_mpu401_uart_new(struct snd_card *card, int device,
526 unsigned short hardware,
528 unsigned int info_flags,
530 struct snd_rawmidi ** rrawmidi)
532 struct snd_mpu401 *mpu;
533 struct snd_rawmidi *rmidi;
534 int in_enable, out_enable;
539 if (! (info_flags & (MPU401_INFO_INPUT | MPU401_INFO_OUTPUT)))
540 info_flags |= MPU401_INFO_INPUT | MPU401_INFO_OUTPUT;
541 in_enable = (info_flags & MPU401_INFO_INPUT) ? 1 : 0;
542 out_enable = (info_flags & MPU401_INFO_OUTPUT) ? 1 : 0;
543 if ((err = snd_rawmidi_new(card, "MPU-401U", device,
544 out_enable, in_enable, &rmidi)) < 0)
546 mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
548 snd_printk(KERN_ERR "mpu401_uart: cannot allocate\n");
549 snd_device_free(card, rmidi);
552 rmidi->private_data = mpu;
553 rmidi->private_free = snd_mpu401_uart_free;
554 spin_lock_init(&mpu->input_lock);
555 spin_lock_init(&mpu->output_lock);
556 spin_lock_init(&mpu->timer_lock);
557 mpu->hardware = hardware;
559 if (! (info_flags & MPU401_INFO_INTEGRATED)) {
560 int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
561 mpu->res = request_region(port, res_size, "MPU401 UART");
562 if (mpu->res == NULL) {
563 snd_printk(KERN_ERR "mpu401_uart: "
564 "unable to grab port 0x%lx size %d\n",
566 snd_device_free(card, rmidi);
570 if (info_flags & MPU401_INFO_MMIO) {
571 mpu->write = mpu401_write_mmio;
572 mpu->read = mpu401_read_mmio;
574 mpu->write = mpu401_write_port;
575 mpu->read = mpu401_read_port;
578 if (hardware == MPU401_HW_PC98II)
579 mpu->cport = port + 2;
581 mpu->cport = port + 1;
583 if (request_irq(irq, snd_mpu401_uart_interrupt, 0,
584 "MPU401 UART", (void *) mpu)) {
585 snd_printk(KERN_ERR "mpu401_uart: "
586 "unable to grab IRQ %d\n", irq);
587 snd_device_free(card, rmidi);
591 if (irq < 0 && !(info_flags & MPU401_INFO_IRQ_HOOK))
592 info_flags |= MPU401_INFO_USE_TIMER;
593 mpu->info_flags = info_flags;
595 if (card->shortname[0])
596 snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI",
599 sprintf(rmidi->name, "MPU-401 MIDI %d-%d",card->number, device);
601 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
602 &snd_mpu401_uart_output);
603 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
606 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
607 &snd_mpu401_uart_input);
608 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
610 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
618 EXPORT_SYMBOL(snd_mpu401_uart_new);
624 static int __init alsa_mpu401_uart_init(void)
629 static void __exit alsa_mpu401_uart_exit(void)
633 module_init(alsa_mpu401_uart_init)
634 module_exit(alsa_mpu401_uart_exit)