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v3.15
 
  1/*
  2 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  3 *  Routines for control of MPU-401 in UART mode
  4 *
  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.
  8 *
  9 *
 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.
 14 *
 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.
 19 *
 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
 23 *
 24 *   13-03-2003:
 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.
 28 *
 29 */
 30
 31#include <asm/io.h>
 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>
 41
 42MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
 43MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
 44MODULE_LICENSE("GPL");
 45
 46static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu);
 47static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu);
 48
 49/*
 50
 51 */
 52
 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))
 57
 58/* Build in lowlevel io */
 59static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data,
 60			      unsigned long addr)
 61{
 62	outb(data, addr);
 63}
 64
 65static unsigned char mpu401_read_port(struct snd_mpu401 *mpu,
 66				      unsigned long addr)
 67{
 68	return inb(addr);
 69}
 70
 71static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data,
 72			      unsigned long addr)
 73{
 74	writeb(data, (void __iomem *)addr);
 75}
 76
 77static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu,
 78				      unsigned long addr)
 79{
 80	return readb((void __iomem *)addr);
 81}
 82/*  */
 83
 84static void snd_mpu401_uart_clear_rx(struct snd_mpu401 *mpu)
 85{
 86	int timeout = 100000;
 87	for (; timeout > 0 && snd_mpu401_input_avail(mpu); timeout--)
 88		mpu->read(mpu, MPU401D(mpu));
 89#ifdef CONFIG_SND_DEBUG
 90	if (timeout <= 0)
 91		snd_printk(KERN_ERR "cmd: clear rx timeout (status = 0x%x)\n",
 92			   mpu->read(mpu, MPU401C(mpu)));
 
 93#endif
 94}
 95
 96static void uart_interrupt_tx(struct snd_mpu401 *mpu)
 97{
 98	unsigned long flags;
 99
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);
105	}
106}
107
108static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
109{
110	unsigned long flags;
111
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);
116		else
117			snd_mpu401_uart_clear_rx(mpu);
118		spin_unlock_irqrestore(&mpu->input_lock, flags);
119	}
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);
124}
125
126/**
127 * snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
128 * @irq: the irq number
129 * @dev_id: mpu401 instance
130 *
131 * Processes the interrupt for MPU401-UART i/o.
132 *
133 * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
134 */
135irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id)
136{
137	struct snd_mpu401 *mpu = dev_id;
138	
139	if (mpu == NULL)
140		return IRQ_NONE;
141	_snd_mpu401_uart_interrupt(mpu);
142	return IRQ_HANDLED;
143}
144
145EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
146
147/**
148 * snd_mpu401_uart_interrupt_tx - generic MPU401-UART transmit irq handler
149 * @irq: the irq number
150 * @dev_id: mpu401 instance
151 *
152 * Processes the interrupt for MPU401-UART output.
153 *
154 * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
155 */
156irqreturn_t snd_mpu401_uart_interrupt_tx(int irq, void *dev_id)
157{
158	struct snd_mpu401 *mpu = dev_id;
159	
160	if (mpu == NULL)
161		return IRQ_NONE;
162	uart_interrupt_tx(mpu);
163	return IRQ_HANDLED;
164}
165
166EXPORT_SYMBOL(snd_mpu401_uart_interrupt_tx);
167
168/*
169 * timer callback
170 * reprogram the timer and call the interrupt job
171 */
172static void snd_mpu401_uart_timer(unsigned long data)
173{
174	struct snd_mpu401 *mpu = (struct snd_mpu401 *)data;
175	unsigned long flags;
176
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);
182	if (mpu->rmidi)
183		_snd_mpu401_uart_interrupt(mpu);
184}
185
186/*
187 * initialize the timer callback if not programmed yet
188 */
189static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input)
190{
191	unsigned long flags;
192
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);
200	} 
201	mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER :
202		MPU401_MODE_OUTPUT_TIMER;
203	spin_unlock_irqrestore (&mpu->timer_lock, flags);
204}
205
206/*
207 * remove the timer callback if still active
208 */
209static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
210{
211	unsigned long flags;
212
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);
219	}
220	spin_unlock_irqrestore (&mpu->timer_lock, flags);
221}
222
223/*
224 * send a UART command
225 * return zero if successful, non-zero for some errors
226 */
227
228static int snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd,
229			       int ack)
230{
231	unsigned long flags;
232	int timeout, ok;
233
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);*/
238	}
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--)
243			udelay(10);
244#ifdef CONFIG_SND_DEBUG
245		if (!timeout)
246			snd_printk(KERN_ERR "cmd: tx timeout (status = 0x%x)\n",
247				   mpu->read(mpu, MPU401C(mpu)));
 
248#endif
249	}
250	mpu->write(mpu, cmd, MPU401C(mpu));
251	if (ack && !(mpu->info_flags & MPU401_INFO_NO_ACK)) {
252		ok = 0;
253		timeout = 10000;
254		while (!ok && timeout-- > 0) {
255			if (snd_mpu401_input_avail(mpu)) {
256				if (mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
257					ok = 1;
258			}
259		}
260		if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
261			ok = 1;
262	} else
263		ok = 1;
264	spin_unlock_irqrestore(&mpu->input_lock, flags);
265	if (!ok) {
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)));
 
270		return 1;
271	}
272	return 0;
273}
274
275static int snd_mpu401_do_reset(struct snd_mpu401 *mpu)
276{
277	if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1))
278		return -EIO;
279	if (snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 0))
280		return -EIO;
281	return 0;
282}
283
284/*
285 * input/output open/close - protected by open_mutex in rawmidi.c
286 */
287static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream *substream)
288{
289	struct snd_mpu401 *mpu;
290	int err;
291
292	mpu = substream->rmidi->private_data;
293	if (mpu->open_input && (err = mpu->open_input(mpu)) < 0)
294		return err;
 
 
 
295	if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
296		if (snd_mpu401_do_reset(mpu) < 0)
297			goto error_out;
298	}
299	mpu->substream_input = substream;
300	set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
301	return 0;
302
303error_out:
304	if (mpu->open_input && mpu->close_input)
305		mpu->close_input(mpu);
306	return -EIO;
307}
308
309static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
310{
311	struct snd_mpu401 *mpu;
312	int err;
313
314	mpu = substream->rmidi->private_data;
315	if (mpu->open_output && (err = mpu->open_output(mpu)) < 0)
316		return err;
 
 
 
317	if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
318		if (snd_mpu401_do_reset(mpu) < 0)
319			goto error_out;
320	}
321	mpu->substream_output = substream;
322	set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
323	return 0;
324
325error_out:
326	if (mpu->open_output && mpu->close_output)
327		mpu->close_output(mpu);
328	return -EIO;
329}
330
331static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream *substream)
332{
333	struct snd_mpu401 *mpu;
334	int err = 0;
335
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);
343	if (err)
344		return -EIO;
345	return 0;
346}
347
348static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream *substream)
349{
350	struct snd_mpu401 *mpu;
351	int err = 0;
352
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);
360	if (err)
361		return -EIO;
362	return 0;
363}
364
365/*
366 * trigger input callback
367 */
368static void
369snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
370{
371	unsigned long flags;
372	struct snd_mpu401 *mpu;
373	int max = 64;
374
375	mpu = substream->rmidi->private_data;
376	if (up) {
377		if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER,
378				       &mpu->mode)) {
379			/* first time - flush FIFO */
380			while (max-- > 0)
381				mpu->read(mpu, MPU401D(mpu));
382			if (mpu->info_flags & MPU401_INFO_USE_TIMER)
383				snd_mpu401_uart_add_timer(mpu, 1);
384		}
385		
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);
390	} else {
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);
394	}
395
396}
397
398/*
399 * transfer input pending data
400 * call with input_lock spinlock held
401 */
402static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
403{
404	int max = 128;
405	unsigned char byte;
406
407	while (max-- > 0) {
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);
413	}
414}
415
416/*
417 *  Tx FIFO sizes:
418 *    CS4237B			- 16 bytes
419 *    AudioDrive ES1688         - 12 bytes
420 *    S3 SonicVibes             -  8 bytes
421 *    SoundBlaster AWE 64       -  2 bytes (ugly hardware)
422 */
423
424/*
425 * write output pending bytes
426 * call with output_lock spinlock held
427 */
428static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
429{
430	unsigned char byte;
431	int max = 256;
432
433	do {
434		if (snd_rawmidi_transmit_peek(mpu->substream_output,
435					      &byte, 1) == 1) {
436			/*
437			 * Try twice because there is hardware that insists on
438			 * setting the output busy bit after each write.
439			 */
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);
445		} else {
446			snd_mpu401_uart_remove_timer (mpu, 0);
447			break;	/* no other data - leave the tx loop */
448		}
449	} while (--max > 0);
450}
451
452/*
453 * output trigger callback
454 */
455static void
456snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
457{
458	unsigned long flags;
459	struct snd_mpu401 *mpu;
460
461	mpu = substream->rmidi->private_data;
462	if (up) {
463		set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
464
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().
468		 */
469		if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
470			snd_mpu401_uart_add_timer(mpu, 0);
471
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);
476	} else {
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);
480	}
481}
482
483/*
484
485 */
486
487static struct snd_rawmidi_ops snd_mpu401_uart_output =
488{
489	.open =		snd_mpu401_uart_output_open,
490	.close =	snd_mpu401_uart_output_close,
491	.trigger =	snd_mpu401_uart_output_trigger,
492};
493
494static struct snd_rawmidi_ops snd_mpu401_uart_input =
495{
496	.open =		snd_mpu401_uart_input_open,
497	.close =	snd_mpu401_uart_input_close,
498	.trigger =	snd_mpu401_uart_input_trigger,
499};
500
501static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
502{
503	struct snd_mpu401 *mpu = rmidi->private_data;
504	if (mpu->irq >= 0)
505		free_irq(mpu->irq, (void *) mpu);
506	release_and_free_resource(mpu->res);
507	kfree(mpu);
508}
509
510/**
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
519 *
520 * Creates a new MPU-401 instance.
521 *
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).
525 *
526 * Return: Zero if successful, or a negative error code.
527 */
528int snd_mpu401_uart_new(struct snd_card *card, int device,
529			unsigned short hardware,
530			unsigned long port,
531			unsigned int info_flags,
532			int irq,
533			struct snd_rawmidi ** rrawmidi)
534{
535	struct snd_mpu401 *mpu;
536	struct snd_rawmidi *rmidi;
537	int in_enable, out_enable;
538	int err;
539
540	if (rrawmidi)
541		*rrawmidi = NULL;
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)
 
548		return err;
549	mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
550	if (mpu == NULL) {
551		snd_printk(KERN_ERR "mpu401_uart: cannot allocate\n");
552		snd_device_free(card, rmidi);
553		return -ENOMEM;
554	}
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;
561	mpu->irq = -1;
 
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",
568				   port, res_size);
569			snd_device_free(card, rmidi);
570			return -EBUSY;
571		}
572	}
573	if (info_flags & MPU401_INFO_MMIO) {
574		mpu->write = mpu401_write_mmio;
575		mpu->read = mpu401_read_mmio;
576	} else {
577		mpu->write = mpu401_write_port;
578		mpu->read = mpu401_read_port;
579	}
580	mpu->port = port;
581	if (hardware == MPU401_HW_PC98II)
582		mpu->cport = port + 2;
583	else
584		mpu->cport = port + 1;
585	if (irq >= 0) {
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);
591			return -EBUSY;
592		}
593	}
594	if (irq < 0 && !(info_flags & MPU401_INFO_IRQ_HOOK))
595		info_flags |= MPU401_INFO_USE_TIMER;
596	mpu->info_flags = info_flags;
597	mpu->irq = irq;
598	if (card->shortname[0])
599		snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI",
600			 card->shortname);
601	else
602		sprintf(rmidi->name, "MPU-401 MIDI %d-%d",card->number, device);
603	if (out_enable) {
604		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
605				    &snd_mpu401_uart_output);
606		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
607	}
608	if (in_enable) {
609		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
610				    &snd_mpu401_uart_input);
611		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
612		if (out_enable)
613			rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
614	}
615	mpu->rmidi = rmidi;
616	if (rrawmidi)
617		*rrawmidi = rmidi;
618	return 0;
 
 
 
619}
620
621EXPORT_SYMBOL(snd_mpu401_uart_new);
622
623/*
624 *  INIT part
625 */
626
627static int __init alsa_mpu401_uart_init(void)
628{
629	return 0;
630}
631
632static void __exit alsa_mpu401_uart_exit(void)
633{
634}
635
636module_init(alsa_mpu401_uart_init)
637module_exit(alsa_mpu401_uart_exit)
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  4 *  Routines for control of MPU-401 in UART mode
  5 *
  6 *  MPU-401 supports UART mode which is not capable generate transmit
  7 *  interrupts thus output is done via polling. Without interrupt,
  8 *  input is done also via polling. Do not expect good performance.
  9 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10 *   13-03-2003:
 11 *      Added support for different kind of hardware I/O. Build in choices
 12 *      are port and mmio. For other kind of I/O, set mpu->read and
 13 *      mpu->write to your own I/O functions.
 
 14 */
 15
 16#include <linux/io.h>
 17#include <linux/delay.h>
 18#include <linux/init.h>
 19#include <linux/slab.h>
 20#include <linux/ioport.h>
 21#include <linux/module.h>
 22#include <linux/interrupt.h>
 23#include <linux/errno.h>
 24#include <sound/core.h>
 25#include <sound/mpu401.h>
 26
 27MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
 28MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
 29MODULE_LICENSE("GPL");
 30
 31static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu);
 32static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu);
 33
 34/*
 35
 36 */
 37
 38#define snd_mpu401_input_avail(mpu) \
 39	(!(mpu->read(mpu, MPU401C(mpu)) & MPU401_RX_EMPTY))
 40#define snd_mpu401_output_ready(mpu) \
 41	(!(mpu->read(mpu, MPU401C(mpu)) & MPU401_TX_FULL))
 42
 43/* Build in lowlevel io */
 44static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data,
 45			      unsigned long addr)
 46{
 47	outb(data, addr);
 48}
 49
 50static unsigned char mpu401_read_port(struct snd_mpu401 *mpu,
 51				      unsigned long addr)
 52{
 53	return inb(addr);
 54}
 55
 56static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data,
 57			      unsigned long addr)
 58{
 59	writeb(data, (void __iomem *)addr);
 60}
 61
 62static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu,
 63				      unsigned long addr)
 64{
 65	return readb((void __iomem *)addr);
 66}
 67/*  */
 68
 69static void snd_mpu401_uart_clear_rx(struct snd_mpu401 *mpu)
 70{
 71	int timeout = 100000;
 72	for (; timeout > 0 && snd_mpu401_input_avail(mpu); timeout--)
 73		mpu->read(mpu, MPU401D(mpu));
 74#ifdef CONFIG_SND_DEBUG
 75	if (timeout <= 0)
 76		dev_err(mpu->rmidi->dev,
 77			"cmd: clear rx timeout (status = 0x%x)\n",
 78			mpu->read(mpu, MPU401C(mpu)));
 79#endif
 80}
 81
 82static void uart_interrupt_tx(struct snd_mpu401 *mpu)
 83{
 84	unsigned long flags;
 85
 86	if (test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode) &&
 87	    test_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode)) {
 88		spin_lock_irqsave(&mpu->output_lock, flags);
 89		snd_mpu401_uart_output_write(mpu);
 90		spin_unlock_irqrestore(&mpu->output_lock, flags);
 91	}
 92}
 93
 94static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
 95{
 96	unsigned long flags;
 97
 98	if (mpu->info_flags & MPU401_INFO_INPUT) {
 99		spin_lock_irqsave(&mpu->input_lock, flags);
100		if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
101			snd_mpu401_uart_input_read(mpu);
102		else
103			snd_mpu401_uart_clear_rx(mpu);
104		spin_unlock_irqrestore(&mpu->input_lock, flags);
105	}
106	if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
107		/* ok. for better Tx performance try do some output
108		   when input is done */
109		uart_interrupt_tx(mpu);
110}
111
112/**
113 * snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
114 * @irq: the irq number
115 * @dev_id: mpu401 instance
116 *
117 * Processes the interrupt for MPU401-UART i/o.
118 *
119 * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
120 */
121irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id)
122{
123	struct snd_mpu401 *mpu = dev_id;
124	
125	if (!mpu)
126		return IRQ_NONE;
127	_snd_mpu401_uart_interrupt(mpu);
128	return IRQ_HANDLED;
129}
130
131EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
132
133/**
134 * snd_mpu401_uart_interrupt_tx - generic MPU401-UART transmit irq handler
135 * @irq: the irq number
136 * @dev_id: mpu401 instance
137 *
138 * Processes the interrupt for MPU401-UART output.
139 *
140 * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
141 */
142irqreturn_t snd_mpu401_uart_interrupt_tx(int irq, void *dev_id)
143{
144	struct snd_mpu401 *mpu = dev_id;
145	
146	if (!mpu)
147		return IRQ_NONE;
148	uart_interrupt_tx(mpu);
149	return IRQ_HANDLED;
150}
151
152EXPORT_SYMBOL(snd_mpu401_uart_interrupt_tx);
153
154/*
155 * timer callback
156 * reprogram the timer and call the interrupt job
157 */
158static void snd_mpu401_uart_timer(struct timer_list *t)
159{
160	struct snd_mpu401 *mpu = from_timer(mpu, t, timer);
161	unsigned long flags;
162
163	spin_lock_irqsave(&mpu->timer_lock, flags);
164	/*mpu->mode |= MPU401_MODE_TIMER;*/
165	mod_timer(&mpu->timer,  1 + jiffies);
 
166	spin_unlock_irqrestore(&mpu->timer_lock, flags);
167	if (mpu->rmidi)
168		_snd_mpu401_uart_interrupt(mpu);
169}
170
171/*
172 * initialize the timer callback if not programmed yet
173 */
174static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input)
175{
176	unsigned long flags;
177
178	spin_lock_irqsave (&mpu->timer_lock, flags);
179	if (mpu->timer_invoked == 0) {
180		timer_setup(&mpu->timer, snd_mpu401_uart_timer, 0);
181		mod_timer(&mpu->timer, 1 + jiffies);
 
 
 
182	} 
183	mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER :
184		MPU401_MODE_OUTPUT_TIMER;
185	spin_unlock_irqrestore (&mpu->timer_lock, flags);
186}
187
188/*
189 * remove the timer callback if still active
190 */
191static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
192{
193	unsigned long flags;
194
195	spin_lock_irqsave (&mpu->timer_lock, flags);
196	if (mpu->timer_invoked) {
197		mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER :
198			~MPU401_MODE_OUTPUT_TIMER;
199		if (! mpu->timer_invoked)
200			del_timer(&mpu->timer);
201	}
202	spin_unlock_irqrestore (&mpu->timer_lock, flags);
203}
204
205/*
206 * send a UART command
207 * return zero if successful, non-zero for some errors
208 */
209
210static int snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd,
211			       int ack)
212{
213	unsigned long flags;
214	int timeout, ok;
215
216	spin_lock_irqsave(&mpu->input_lock, flags);
217	if (mpu->hardware != MPU401_HW_TRID4DWAVE) {
218		mpu->write(mpu, 0x00, MPU401D(mpu));
219		/*snd_mpu401_uart_clear_rx(mpu);*/
220	}
221	/* ok. standard MPU-401 initialization */
222	if (mpu->hardware != MPU401_HW_SB) {
223		for (timeout = 1000; timeout > 0 &&
224			     !snd_mpu401_output_ready(mpu); timeout--)
225			udelay(10);
226#ifdef CONFIG_SND_DEBUG
227		if (!timeout)
228			dev_err(mpu->rmidi->dev,
229				"cmd: tx timeout (status = 0x%x)\n",
230				mpu->read(mpu, MPU401C(mpu)));
231#endif
232	}
233	mpu->write(mpu, cmd, MPU401C(mpu));
234	if (ack && !(mpu->info_flags & MPU401_INFO_NO_ACK)) {
235		ok = 0;
236		timeout = 10000;
237		while (!ok && timeout-- > 0) {
238			if (snd_mpu401_input_avail(mpu)) {
239				if (mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
240					ok = 1;
241			}
242		}
243		if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
244			ok = 1;
245	} else
246		ok = 1;
247	spin_unlock_irqrestore(&mpu->input_lock, flags);
248	if (!ok) {
249		dev_err(mpu->rmidi->dev,
250			"cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)\n",
251			cmd, mpu->port,
252			mpu->read(mpu, MPU401C(mpu)),
253			mpu->read(mpu, MPU401D(mpu)));
254		return 1;
255	}
256	return 0;
257}
258
259static int snd_mpu401_do_reset(struct snd_mpu401 *mpu)
260{
261	if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1))
262		return -EIO;
263	if (snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 0))
264		return -EIO;
265	return 0;
266}
267
268/*
269 * input/output open/close - protected by open_mutex in rawmidi.c
270 */
271static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream *substream)
272{
273	struct snd_mpu401 *mpu;
274	int err;
275
276	mpu = substream->rmidi->private_data;
277	if (mpu->open_input) {
278		err = mpu->open_input(mpu);
279		if (err < 0)
280			return err;
281	}
282	if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
283		if (snd_mpu401_do_reset(mpu) < 0)
284			goto error_out;
285	}
286	mpu->substream_input = substream;
287	set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
288	return 0;
289
290error_out:
291	if (mpu->open_input && mpu->close_input)
292		mpu->close_input(mpu);
293	return -EIO;
294}
295
296static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
297{
298	struct snd_mpu401 *mpu;
299	int err;
300
301	mpu = substream->rmidi->private_data;
302	if (mpu->open_output) {
303		err = mpu->open_output(mpu);
304		if (err < 0)
305			return err;
306	}
307	if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
308		if (snd_mpu401_do_reset(mpu) < 0)
309			goto error_out;
310	}
311	mpu->substream_output = substream;
312	set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
313	return 0;
314
315error_out:
316	if (mpu->open_output && mpu->close_output)
317		mpu->close_output(mpu);
318	return -EIO;
319}
320
321static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream *substream)
322{
323	struct snd_mpu401 *mpu;
324	int err = 0;
325
326	mpu = substream->rmidi->private_data;
327	clear_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
328	mpu->substream_input = NULL;
329	if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode))
330		err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
331	if (mpu->close_input)
332		mpu->close_input(mpu);
333	if (err)
334		return -EIO;
335	return 0;
336}
337
338static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream *substream)
339{
340	struct snd_mpu401 *mpu;
341	int err = 0;
342
343	mpu = substream->rmidi->private_data;
344	clear_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
345	mpu->substream_output = NULL;
346	if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
347		err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
348	if (mpu->close_output)
349		mpu->close_output(mpu);
350	if (err)
351		return -EIO;
352	return 0;
353}
354
355/*
356 * trigger input callback
357 */
358static void
359snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
360{
361	unsigned long flags;
362	struct snd_mpu401 *mpu;
363	int max = 64;
364
365	mpu = substream->rmidi->private_data;
366	if (up) {
367		if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER,
368				       &mpu->mode)) {
369			/* first time - flush FIFO */
370			while (max-- > 0)
371				mpu->read(mpu, MPU401D(mpu));
372			if (mpu->info_flags & MPU401_INFO_USE_TIMER)
373				snd_mpu401_uart_add_timer(mpu, 1);
374		}
375		
376		/* read data in advance */
377		spin_lock_irqsave(&mpu->input_lock, flags);
378		snd_mpu401_uart_input_read(mpu);
379		spin_unlock_irqrestore(&mpu->input_lock, flags);
380	} else {
381		if (mpu->info_flags & MPU401_INFO_USE_TIMER)
382			snd_mpu401_uart_remove_timer(mpu, 1);
383		clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
384	}
385
386}
387
388/*
389 * transfer input pending data
390 * call with input_lock spinlock held
391 */
392static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
393{
394	int max = 128;
395	unsigned char byte;
396
397	while (max-- > 0) {
398		if (! snd_mpu401_input_avail(mpu))
399			break; /* input not available */
400		byte = mpu->read(mpu, MPU401D(mpu));
401		if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
402			snd_rawmidi_receive(mpu->substream_input, &byte, 1);
403	}
404}
405
406/*
407 *  Tx FIFO sizes:
408 *    CS4237B			- 16 bytes
409 *    AudioDrive ES1688         - 12 bytes
410 *    S3 SonicVibes             -  8 bytes
411 *    SoundBlaster AWE 64       -  2 bytes (ugly hardware)
412 */
413
414/*
415 * write output pending bytes
416 * call with output_lock spinlock held
417 */
418static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
419{
420	unsigned char byte;
421	int max = 256;
422
423	do {
424		if (snd_rawmidi_transmit_peek(mpu->substream_output,
425					      &byte, 1) == 1) {
426			/*
427			 * Try twice because there is hardware that insists on
428			 * setting the output busy bit after each write.
429			 */
430			if (!snd_mpu401_output_ready(mpu) &&
431			    !snd_mpu401_output_ready(mpu))
432				break;	/* Tx FIFO full - try again later */
433			mpu->write(mpu, byte, MPU401D(mpu));
434			snd_rawmidi_transmit_ack(mpu->substream_output, 1);
435		} else {
436			snd_mpu401_uart_remove_timer (mpu, 0);
437			break;	/* no other data - leave the tx loop */
438		}
439	} while (--max > 0);
440}
441
442/*
443 * output trigger callback
444 */
445static void
446snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
447{
448	unsigned long flags;
449	struct snd_mpu401 *mpu;
450
451	mpu = substream->rmidi->private_data;
452	if (up) {
453		set_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
454
455		/* try to add the timer at each output trigger,
456		 * since the output timer might have been removed in
457		 * snd_mpu401_uart_output_write().
458		 */
459		if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
460			snd_mpu401_uart_add_timer(mpu, 0);
461
462		/* output pending data */
463		spin_lock_irqsave(&mpu->output_lock, flags);
464		snd_mpu401_uart_output_write(mpu);
465		spin_unlock_irqrestore(&mpu->output_lock, flags);
466	} else {
467		if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
468			snd_mpu401_uart_remove_timer(mpu, 0);
469		clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
470	}
471}
472
473/*
474
475 */
476
477static const struct snd_rawmidi_ops snd_mpu401_uart_output =
478{
479	.open =		snd_mpu401_uart_output_open,
480	.close =	snd_mpu401_uart_output_close,
481	.trigger =	snd_mpu401_uart_output_trigger,
482};
483
484static const struct snd_rawmidi_ops snd_mpu401_uart_input =
485{
486	.open =		snd_mpu401_uart_input_open,
487	.close =	snd_mpu401_uart_input_close,
488	.trigger =	snd_mpu401_uart_input_trigger,
489};
490
491static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
492{
493	struct snd_mpu401 *mpu = rmidi->private_data;
494	if (mpu->irq >= 0)
495		free_irq(mpu->irq, (void *) mpu);
496	release_and_free_resource(mpu->res);
497	kfree(mpu);
498}
499
500/**
501 * snd_mpu401_uart_new - create an MPU401-UART instance
502 * @card: the card instance
503 * @device: the device index, zero-based
504 * @hardware: the hardware type, MPU401_HW_XXXX
505 * @port: the base address of MPU401 port
506 * @info_flags: bitflags MPU401_INFO_XXX
507 * @irq: the ISA irq number, -1 if not to be allocated
508 * @rrawmidi: the pointer to store the new rawmidi instance
509 *
510 * Creates a new MPU-401 instance.
511 *
512 * Note that the rawmidi instance is returned on the rrawmidi argument,
513 * not the mpu401 instance itself.  To access to the mpu401 instance,
514 * cast from rawmidi->private_data (with struct snd_mpu401 magic-cast).
515 *
516 * Return: Zero if successful, or a negative error code.
517 */
518int snd_mpu401_uart_new(struct snd_card *card, int device,
519			unsigned short hardware,
520			unsigned long port,
521			unsigned int info_flags,
522			int irq,
523			struct snd_rawmidi ** rrawmidi)
524{
525	struct snd_mpu401 *mpu;
526	struct snd_rawmidi *rmidi;
527	int in_enable, out_enable;
528	int err;
529
530	if (rrawmidi)
531		*rrawmidi = NULL;
532	if (! (info_flags & (MPU401_INFO_INPUT | MPU401_INFO_OUTPUT)))
533		info_flags |= MPU401_INFO_INPUT | MPU401_INFO_OUTPUT;
534	in_enable = (info_flags & MPU401_INFO_INPUT) ? 1 : 0;
535	out_enable = (info_flags & MPU401_INFO_OUTPUT) ? 1 : 0;
536	err = snd_rawmidi_new(card, "MPU-401U", device,
537			      out_enable, in_enable, &rmidi);
538	if (err < 0)
539		return err;
540	mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
541	if (!mpu) {
542		err = -ENOMEM;
543		goto free_device;
 
544	}
545	rmidi->private_data = mpu;
546	rmidi->private_free = snd_mpu401_uart_free;
547	spin_lock_init(&mpu->input_lock);
548	spin_lock_init(&mpu->output_lock);
549	spin_lock_init(&mpu->timer_lock);
550	mpu->hardware = hardware;
551	mpu->irq = -1;
552	mpu->rmidi = rmidi;
553	if (! (info_flags & MPU401_INFO_INTEGRATED)) {
554		int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
555		mpu->res = request_region(port, res_size, "MPU401 UART");
556		if (!mpu->res) {
557			dev_err(rmidi->dev,
558				"mpu401_uart: unable to grab port 0x%lx size %d\n",
559				port, res_size);
560			err = -EBUSY;
561			goto free_device;
562		}
563	}
564	if (info_flags & MPU401_INFO_MMIO) {
565		mpu->write = mpu401_write_mmio;
566		mpu->read = mpu401_read_mmio;
567	} else {
568		mpu->write = mpu401_write_port;
569		mpu->read = mpu401_read_port;
570	}
571	mpu->port = port;
572	if (hardware == MPU401_HW_PC98II)
573		mpu->cport = port + 2;
574	else
575		mpu->cport = port + 1;
576	if (irq >= 0) {
577		if (request_irq(irq, snd_mpu401_uart_interrupt, 0,
578				"MPU401 UART", (void *) mpu)) {
579			dev_err(rmidi->dev,
580				"mpu401_uart: unable to grab IRQ %d\n", irq);
581			err = -EBUSY;
582			goto free_device;
583		}
584	}
585	if (irq < 0 && !(info_flags & MPU401_INFO_IRQ_HOOK))
586		info_flags |= MPU401_INFO_USE_TIMER;
587	mpu->info_flags = info_flags;
588	mpu->irq = irq;
589	if (card->shortname[0])
590		snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI",
591			 card->shortname);
592	else
593		sprintf(rmidi->name, "MPU-401 MIDI %d-%d",card->number, device);
594	if (out_enable) {
595		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
596				    &snd_mpu401_uart_output);
597		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
598	}
599	if (in_enable) {
600		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
601				    &snd_mpu401_uart_input);
602		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
603		if (out_enable)
604			rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
605	}
 
606	if (rrawmidi)
607		*rrawmidi = rmidi;
608	return 0;
609free_device:
610	snd_device_free(card, rmidi);
611	return err;
612}
613
614EXPORT_SYMBOL(snd_mpu401_uart_new);