sound/pci/emu10k1/emumpu401.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  *  Routines for control of EMU10K1 MPU-401 in UART mode
  */

 #include <linux/time.h>
 #include <linux/init.h>
 #include <sound/core.h>
 #include <sound/emu10k1.h>

 #define EMU10K1_MIDI_MODE_INPUT		(1<<0)
 #define EMU10K1_MIDI_MODE_OUTPUT	(1<<1)

 static inline unsigned char mpu401_read(struct snd_emu10k1 *emu,
 					struct snd_emu10k1_midi *mpu, int idx)
 {
 	if (emu->audigy)
 		return (unsigned char)snd_emu10k1_ptr_read(emu, mpu->port + idx, 0);
 	else
 		return inb(emu->port + mpu->port + idx);
 }

 static inline void mpu401_write(struct snd_emu10k1 *emu,
 				struct snd_emu10k1_midi *mpu, int data, int idx)
 {
 	if (emu->audigy)
 		snd_emu10k1_ptr_write(emu, mpu->port + idx, 0, data);
 	else
 		outb(data, emu->port + mpu->port + idx);
 }

 #define mpu401_write_data(emu, mpu, data)	mpu401_write(emu, mpu, data, 0)
 #define mpu401_write_cmd(emu, mpu, data)	mpu401_write(emu, mpu, data, 1)
 #define mpu401_read_data(emu, mpu)		mpu401_read(emu, mpu, 0)
 #define mpu401_read_stat(emu, mpu)		mpu401_read(emu, mpu, 1)

 #define mpu401_input_avail(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x80))
 #define mpu401_output_ready(emu,mpu)	(!(mpu401_read_stat(emu,mpu) & 0x40))

 #define MPU401_RESET		0xff
 #define MPU401_ENTER_UART	0x3f
 #define MPU401_ACK		0xfe

 static void mpu401_clear_rx(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *mpu)
 {
 	int timeout = 100000;
 	for (; timeout > 0 && mpu401_input_avail(emu, mpu); timeout--)
 		mpu401_read_data(emu, mpu);
 #ifdef CONFIG_SND_DEBUG
 	if (timeout <= 0)
 		dev_err(emu->card->dev,
 			"cmd: clear rx timeout (status = 0x%x)\n",
 			mpu401_read_stat(emu, mpu));
 #endif
 }

 /*

  */

 static void do_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, unsigned int status)
 {
 	unsigned char byte;

 	if (midi->rmidi == NULL) {
 		snd_emu10k1_intr_disable(emu, midi->tx_enable | midi->rx_enable);
 		return;
 	}

 	spin_lock(&midi->input_lock);
 	if ((status & midi->ipr_rx) && mpu401_input_avail(emu, midi)) {
 		if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
 			mpu401_clear_rx(emu, midi);
 		} else {
 			byte = mpu401_read_data(emu, midi);
 			if (midi->substream_input)
 				snd_rawmidi_receive(midi->substream_input, &byte, 1);
 		}
 	}
 	spin_unlock(&midi->input_lock);

 	spin_lock(&midi->output_lock);
 	if ((status & midi->ipr_tx) && mpu401_output_ready(emu, midi)) {
 		if (midi->substream_output &&
 		    snd_rawmidi_transmit(midi->substream_output, &byte, 1) == 1) {
 			mpu401_write_data(emu, midi, byte);
 		} else {
 			snd_emu10k1_intr_disable(emu, midi->tx_enable);
 		}
 	}
 	spin_unlock(&midi->output_lock);
 }

 static void snd_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, unsigned int status)
 {
 	do_emu10k1_midi_interrupt(emu, &emu->midi, status);
 }

 static void snd_emu10k1_midi_interrupt2(struct snd_emu10k1 *emu, unsigned int status)
 {
 	do_emu10k1_midi_interrupt(emu, &emu->midi2, status);
 }

 static int snd_emu10k1_midi_cmd(struct snd_emu10k1 * emu, struct snd_emu10k1_midi *midi, unsigned char cmd, int ack)
 {
 	unsigned long flags;
 	int timeout, ok;

 	spin_lock_irqsave(&midi->input_lock, flags);
 	mpu401_write_data(emu, midi, 0x00);
 	/* mpu401_clear_rx(emu, midi); */

 	mpu401_write_cmd(emu, midi, cmd);
 	if (ack) {
 		ok = 0;
 		timeout = 10000;
 		while (!ok && timeout-- > 0) {
 			if (mpu401_input_avail(emu, midi)) {
 				if (mpu401_read_data(emu, midi) == MPU401_ACK)
 					ok = 1;
 			}
 		}
 		if (!ok && mpu401_read_data(emu, midi) == MPU401_ACK)
 			ok = 1;
 	} else {
 		ok = 1;
 	}
 	spin_unlock_irqrestore(&midi->input_lock, flags);
 	if (!ok) {
 		dev_err(emu->card->dev,
 			"midi_cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)!!!\n",
 			   cmd, emu->port,
 			   mpu401_read_stat(emu, midi),
 			   mpu401_read_data(emu, midi));
 		return 1;
 	}
 	return 0;
 }

 static int snd_emu10k1_midi_input_open(struct snd_rawmidi_substream *substream)
 {
 	struct snd_emu10k1 *emu;
 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
 	unsigned long flags;

 	emu = midi->emu;
 	if (snd_BUG_ON(!emu))
 		return -ENXIO;
 	spin_lock_irqsave(&midi->open_lock, flags);
 	midi->midi_mode |= EMU10K1_MIDI_MODE_INPUT;
 	midi->substream_input = substream;
 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
 			goto error_out;
 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
 			goto error_out;
 	} else {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 	}
 	return 0;

 error_out:
 	return -EIO;
 }

 static int snd_emu10k1_midi_output_open(struct snd_rawmidi_substream *substream)
 {
 	struct snd_emu10k1 *emu;
 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
 	unsigned long flags;

 	emu = midi->emu;
 	if (snd_BUG_ON(!emu))
 		return -ENXIO;
 	spin_lock_irqsave(&midi->open_lock, flags);
 	midi->midi_mode |= EMU10K1_MIDI_MODE_OUTPUT;
 	midi->substream_output = substream;
 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
 			goto error_out;
 		if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
 			goto error_out;
 	} else {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 	}
 	return 0;

 error_out:
 	return -EIO;
 }

 static int snd_emu10k1_midi_input_close(struct snd_rawmidi_substream *substream)
 {
 	struct snd_emu10k1 *emu;
 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
 	unsigned long flags;
 	int err = 0;

 	emu = midi->emu;
 	if (snd_BUG_ON(!emu))
 		return -ENXIO;
 	spin_lock_irqsave(&midi->open_lock, flags);
 	snd_emu10k1_intr_disable(emu, midi->rx_enable);
 	midi->midi_mode &= ~EMU10K1_MIDI_MODE_INPUT;
 	midi->substream_input = NULL;
 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
 	} else {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 	}
 	return err;
 }

 static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
 {
 	struct snd_emu10k1 *emu;
 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
 	unsigned long flags;
 	int err = 0;

 	emu = midi->emu;
 	if (snd_BUG_ON(!emu))
 		return -ENXIO;
 	spin_lock_irqsave(&midi->open_lock, flags);
 	snd_emu10k1_intr_disable(emu, midi->tx_enable);
 	midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
 	midi->substream_output = NULL;
 	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 		err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
 	} else {
 		spin_unlock_irqrestore(&midi->open_lock, flags);
 	}
 	return err;
 }

 static void snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
 {
 	struct snd_emu10k1 *emu;
 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
 	emu = midi->emu;
 	if (snd_BUG_ON(!emu))
 		return;

 	if (up)
 		snd_emu10k1_intr_enable(emu, midi->rx_enable);
 	else
 		snd_emu10k1_intr_disable(emu, midi->rx_enable);
 }

 static void snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
 {
 	struct snd_emu10k1 *emu;
 	struct snd_emu10k1_midi *midi = (struct snd_emu10k1_midi *)substream->rmidi->private_data;
 	unsigned long flags;

 	emu = midi->emu;
 	if (snd_BUG_ON(!emu))
 		return;

 	if (up) {
 		int max = 4;
 		unsigned char byte;

 		/* try to send some amount of bytes here before interrupts */
 		spin_lock_irqsave(&midi->output_lock, flags);
 		while (max > 0) {
 			if (mpu401_output_ready(emu, midi)) {
 				if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT) ||
 				    snd_rawmidi_transmit(substream, &byte, 1) != 1) {
 					/* no more data */
 					spin_unlock_irqrestore(&midi->output_lock, flags);
 					return;
 				}
 				mpu401_write_data(emu, midi, byte);
 				max--;
 			} else {
 				break;
 			}
 		}
 		spin_unlock_irqrestore(&midi->output_lock, flags);
 		snd_emu10k1_intr_enable(emu, midi->tx_enable);
 	} else {
 		snd_emu10k1_intr_disable(emu, midi->tx_enable);
 	}
 }

 /*

  */

 static const struct snd_rawmidi_ops snd_emu10k1_midi_output =
 {
 	.open =		snd_emu10k1_midi_output_open,
 	.close =	snd_emu10k1_midi_output_close,
 	.trigger =	snd_emu10k1_midi_output_trigger,
 };

 static const struct snd_rawmidi_ops snd_emu10k1_midi_input =
 {
 	.open =		snd_emu10k1_midi_input_open,
 	.close =	snd_emu10k1_midi_input_close,
 	.trigger =	snd_emu10k1_midi_input_trigger,
 };

 static void snd_emu10k1_midi_free(struct snd_rawmidi *rmidi)
 {
 	struct snd_emu10k1_midi *midi = rmidi->private_data;
 	midi->interrupt = NULL;
 	midi->rmidi = NULL;
 }

 static int emu10k1_midi_init(struct snd_emu10k1 *emu, struct snd_emu10k1_midi *midi, int device, char *name)
 {
 	struct snd_rawmidi *rmidi;
 	int err;

 	if ((err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi)) < 0)
 		return err;
 	midi->emu = emu;
 	spin_lock_init(&midi->open_lock);
 	spin_lock_init(&midi->input_lock);
 	spin_lock_init(&midi->output_lock);
 	strcpy(rmidi->name, name);
 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1_midi_output);
 	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1_midi_input);
 	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
 	                     SNDRV_RAWMIDI_INFO_INPUT |
 	                     SNDRV_RAWMIDI_INFO_DUPLEX;
 	rmidi->private_data = midi;
 	rmidi->private_free = snd_emu10k1_midi_free;
 	midi->rmidi = rmidi;
 	return 0;
 }

 int snd_emu10k1_midi(struct snd_emu10k1 *emu)
 {
 	struct snd_emu10k1_midi *midi = &emu->midi;
 	int err;

 	if ((err = emu10k1_midi_init(emu, midi, 0, "EMU10K1 MPU-401 (UART)")) < 0)
 		return err;

 	midi->tx_enable = INTE_MIDITXENABLE;
 	midi->rx_enable = INTE_MIDIRXENABLE;
 	midi->port = MUDATA;
 	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
 	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
 	midi->interrupt = snd_emu10k1_midi_interrupt;
 	return 0;
 }

 int snd_emu10k1_audigy_midi(struct snd_emu10k1 *emu)
 {
 	struct snd_emu10k1_midi *midi;
 	int err;

 	midi = &emu->midi;
 	if ((err = emu10k1_midi_init(emu, midi, 0, "Audigy MPU-401 (UART)")) < 0)
 		return err;

 	midi->tx_enable = INTE_MIDITXENABLE;
 	midi->rx_enable = INTE_MIDIRXENABLE;
 	midi->port = A_MUDATA1;
 	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
 	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
 	midi->interrupt = snd_emu10k1_midi_interrupt;

 	midi = &emu->midi2;
 	if ((err = emu10k1_midi_init(emu, midi, 1, "Audigy MPU-401 #2")) < 0)
 		return err;

 	midi->tx_enable = INTE_A_MIDITXENABLE2;
 	midi->rx_enable = INTE_A_MIDIRXENABLE2;
 	midi->port = A_MUDATA2;
 	midi->ipr_tx = IPR_A_MIDITRANSBUFEMPTY2;
 	midi->ipr_rx = IPR_A_MIDIRECVBUFEMPTY2;
 	midi->interrupt = snd_emu10k1_midi_interrupt2;
 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
	* Routines for control of EMU10K1 MPU-401 in UART mode
	*/

	#include <linux/time.h>
	#include <linux/init.h>
	#include <sound/core.h>
	#include <sound/emu10k1.h>

	#define EMU10K1_MIDI_MODE_INPUT (1<<0)
	#define EMU10K1_MIDI_MODE_OUTPUT (1<<1)

	static inline unsigned char mpu401_read(struct snd_emu10k1 *emu,
	struct snd_emu10k1_midi *mpu, int idx)
	{
	if (emu->audigy)
	return (unsigned char)snd_emu10k1_ptr_read(emu, mpu->port + idx, 0);
	else
	return inb(emu->port + mpu->port + idx);
	}

	static inline void mpu401_write(struct snd_emu10k1 *emu,
	struct snd_emu10k1_midi *mpu, int data, int idx)
	{
	if (emu->audigy)
	snd_emu10k1_ptr_write(emu, mpu->port + idx, 0, data);
	else
	outb(data, emu->port + mpu->port + idx);
	}

	#define mpu401_write_data(emu, mpu, data) mpu401_write(emu, mpu, data, 0)
	#define mpu401_write_cmd(emu, mpu, data) mpu401_write(emu, mpu, data, 1)
	#define mpu401_read_data(emu, mpu) mpu401_read(emu, mpu, 0)
	#define mpu401_read_stat(emu, mpu) mpu401_read(emu, mpu, 1)

	#define mpu401_input_avail(emu,mpu) (!(mpu401_read_stat(emu,mpu) & 0x80))
	#define mpu401_output_ready(emu,mpu) (!(mpu401_read_stat(emu,mpu) & 0x40))

	#define MPU401_RESET 0xff
	#define MPU401_ENTER_UART 0x3f
	#define MPU401_ACK 0xfe

	static void mpu401_clear_rx(struct snd_emu10k1 emu, struct snd_emu10k1_midi mpu)
	{
	int timeout = 100000;
	for (; timeout > 0 && mpu401_input_avail(emu, mpu); timeout--)
	mpu401_read_data(emu, mpu);
	#ifdef CONFIG_SND_DEBUG
	if (timeout <= 0)
	dev_err(emu->card->dev,
	"cmd: clear rx timeout (status = 0x%x)\n",
	mpu401_read_stat(emu, mpu));
	#endif
	}

	/*

	*/

	static void do_emu10k1_midi_interrupt(struct snd_emu10k1 emu, struct snd_emu10k1_midi midi, unsigned int status)
	{
	unsigned char byte;

	if (midi->rmidi == NULL) {
	snd_emu10k1_intr_disable(emu, midi->tx_enable \| midi->rx_enable);
	return;
	}

	spin_lock(&midi->input_lock);
	if ((status & midi->ipr_rx) && mpu401_input_avail(emu, midi)) {
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
	mpu401_clear_rx(emu, midi);
	} else {
	byte = mpu401_read_data(emu, midi);
	if (midi->substream_input)
	snd_rawmidi_receive(midi->substream_input, &byte, 1);
	}
	}
	spin_unlock(&midi->input_lock);

	spin_lock(&midi->output_lock);
	if ((status & midi->ipr_tx) && mpu401_output_ready(emu, midi)) {
	if (midi->substream_output &&
	snd_rawmidi_transmit(midi->substream_output, &byte, 1) == 1) {
	mpu401_write_data(emu, midi, byte);
	} else {
	snd_emu10k1_intr_disable(emu, midi->tx_enable);
	}
	}
	spin_unlock(&midi->output_lock);
	}

	static void snd_emu10k1_midi_interrupt(struct snd_emu10k1 *emu, unsigned int status)
	{
	do_emu10k1_midi_interrupt(emu, &emu->midi, status);
	}

	static void snd_emu10k1_midi_interrupt2(struct snd_emu10k1 *emu, unsigned int status)
	{
	do_emu10k1_midi_interrupt(emu, &emu->midi2, status);
	}

	static int snd_emu10k1_midi_cmd(struct snd_emu10k1 * emu, struct snd_emu10k1_midi *midi, unsigned char cmd, int ack)
	{
	unsigned long flags;
	int timeout, ok;

	spin_lock_irqsave(&midi->input_lock, flags);
	mpu401_write_data(emu, midi, 0x00);
	/* mpu401_clear_rx(emu, midi); */

	mpu401_write_cmd(emu, midi, cmd);
	if (ack) {
	ok = 0;
	timeout = 10000;
	while (!ok && timeout-- > 0) {
	if (mpu401_input_avail(emu, midi)) {
	if (mpu401_read_data(emu, midi) == MPU401_ACK)
	ok = 1;
	}
	}
	if (!ok && mpu401_read_data(emu, midi) == MPU401_ACK)
	ok = 1;
	} else {
	ok = 1;
	}
	spin_unlock_irqrestore(&midi->input_lock, flags);
	if (!ok) {
	dev_err(emu->card->dev,
	"midi_cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)!!!\n",
	cmd, emu->port,
	mpu401_read_stat(emu, midi),
	mpu401_read_data(emu, midi));
	return 1;
	}
	return 0;
	}

	static int snd_emu10k1_midi_input_open(struct snd_rawmidi_substream *substream)
	{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi midi = (struct snd_emu10k1_midi )substream->rmidi->private_data;
	unsigned long flags;

	emu = midi->emu;
	if (snd_BUG_ON(!emu))
	return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	midi->midi_mode \|= EMU10K1_MIDI_MODE_INPUT;
	midi->substream_input = substream;
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
	goto error_out;
	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
	goto error_out;
	} else {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return 0;

	error_out:
	return -EIO;
	}

	static int snd_emu10k1_midi_output_open(struct snd_rawmidi_substream *substream)
	{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi midi = (struct snd_emu10k1_midi )substream->rmidi->private_data;
	unsigned long flags;

	emu = midi->emu;
	if (snd_BUG_ON(!emu))
	return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	midi->midi_mode \|= EMU10K1_MIDI_MODE_OUTPUT;
	midi->substream_output = substream;
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 1))
	goto error_out;
	if (snd_emu10k1_midi_cmd(emu, midi, MPU401_ENTER_UART, 1))
	goto error_out;
	} else {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return 0;

	error_out:
	return -EIO;
	}

	static int snd_emu10k1_midi_input_close(struct snd_rawmidi_substream *substream)
	{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi midi = (struct snd_emu10k1_midi )substream->rmidi->private_data;
	unsigned long flags;
	int err = 0;

	emu = midi->emu;
	if (snd_BUG_ON(!emu))
	return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	snd_emu10k1_intr_disable(emu, midi->rx_enable);
	midi->midi_mode &= ~EMU10K1_MIDI_MODE_INPUT;
	midi->substream_input = NULL;
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT)) {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
	} else {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return err;
	}

	static int snd_emu10k1_midi_output_close(struct snd_rawmidi_substream *substream)
	{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi midi = (struct snd_emu10k1_midi )substream->rmidi->private_data;
	unsigned long flags;
	int err = 0;

	emu = midi->emu;
	if (snd_BUG_ON(!emu))
	return -ENXIO;
	spin_lock_irqsave(&midi->open_lock, flags);
	snd_emu10k1_intr_disable(emu, midi->tx_enable);
	midi->midi_mode &= ~EMU10K1_MIDI_MODE_OUTPUT;
	midi->substream_output = NULL;
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_INPUT)) {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	err = snd_emu10k1_midi_cmd(emu, midi, MPU401_RESET, 0);
	} else {
	spin_unlock_irqrestore(&midi->open_lock, flags);
	}
	return err;
	}

	static void snd_emu10k1_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
	{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi midi = (struct snd_emu10k1_midi )substream->rmidi->private_data;
	emu = midi->emu;
	if (snd_BUG_ON(!emu))
	return;

	if (up)
	snd_emu10k1_intr_enable(emu, midi->rx_enable);
	else
	snd_emu10k1_intr_disable(emu, midi->rx_enable);
	}

	static void snd_emu10k1_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
	{
	struct snd_emu10k1 *emu;
	struct snd_emu10k1_midi midi = (struct snd_emu10k1_midi )substream->rmidi->private_data;
	unsigned long flags;

	emu = midi->emu;
	if (snd_BUG_ON(!emu))
	return;

	if (up) {
	int max = 4;
	unsigned char byte;

	/* try to send some amount of bytes here before interrupts */
	spin_lock_irqsave(&midi->output_lock, flags);
	while (max > 0) {
	if (mpu401_output_ready(emu, midi)) {
	if (!(midi->midi_mode & EMU10K1_MIDI_MODE_OUTPUT) \|\|
	snd_rawmidi_transmit(substream, &byte, 1) != 1) {
	/* no more data */
	spin_unlock_irqrestore(&midi->output_lock, flags);
	return;
	}
	mpu401_write_data(emu, midi, byte);
	max--;
	} else {
	break;
	}
	}
	spin_unlock_irqrestore(&midi->output_lock, flags);
	snd_emu10k1_intr_enable(emu, midi->tx_enable);
	} else {
	snd_emu10k1_intr_disable(emu, midi->tx_enable);
	}
	}

	/*

	*/

	static const struct snd_rawmidi_ops snd_emu10k1_midi_output =
	{
	.open = snd_emu10k1_midi_output_open,
	.close = snd_emu10k1_midi_output_close,
	.trigger = snd_emu10k1_midi_output_trigger,
	};

	static const struct snd_rawmidi_ops snd_emu10k1_midi_input =
	{
	.open = snd_emu10k1_midi_input_open,
	.close = snd_emu10k1_midi_input_close,
	.trigger = snd_emu10k1_midi_input_trigger,
	};

	static void snd_emu10k1_midi_free(struct snd_rawmidi *rmidi)
	{
	struct snd_emu10k1_midi *midi = rmidi->private_data;
	midi->interrupt = NULL;
	midi->rmidi = NULL;
	}

	static int emu10k1_midi_init(struct snd_emu10k1 emu, struct snd_emu10k1_midi midi, int device, char *name)
	{
	struct snd_rawmidi *rmidi;
	int err;

	if ((err = snd_rawmidi_new(emu->card, name, device, 1, 1, &rmidi)) < 0)
	return err;
	midi->emu = emu;
	spin_lock_init(&midi->open_lock);
	spin_lock_init(&midi->input_lock);
	spin_lock_init(&midi->output_lock);
	strcpy(rmidi->name, name);
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_emu10k1_midi_output);
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_emu10k1_midi_input);
	rmidi->info_flags \|= SNDRV_RAWMIDI_INFO_OUTPUT \|
	SNDRV_RAWMIDI_INFO_INPUT \|
	SNDRV_RAWMIDI_INFO_DUPLEX;
	rmidi->private_data = midi;
	rmidi->private_free = snd_emu10k1_midi_free;
	midi->rmidi = rmidi;
	return 0;
	}

	int snd_emu10k1_midi(struct snd_emu10k1 *emu)
	{
	struct snd_emu10k1_midi *midi = &emu->midi;
	int err;

	if ((err = emu10k1_midi_init(emu, midi, 0, "EMU10K1 MPU-401 (UART)")) < 0)
	return err;

	midi->tx_enable = INTE_MIDITXENABLE;
	midi->rx_enable = INTE_MIDIRXENABLE;
	midi->port = MUDATA;
	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
	midi->interrupt = snd_emu10k1_midi_interrupt;
	return 0;
	}

	int snd_emu10k1_audigy_midi(struct snd_emu10k1 *emu)
	{
	struct snd_emu10k1_midi *midi;
	int err;

	midi = &emu->midi;
	if ((err = emu10k1_midi_init(emu, midi, 0, "Audigy MPU-401 (UART)")) < 0)
	return err;

	midi->tx_enable = INTE_MIDITXENABLE;
	midi->rx_enable = INTE_MIDIRXENABLE;
	midi->port = A_MUDATA1;
	midi->ipr_tx = IPR_MIDITRANSBUFEMPTY;
	midi->ipr_rx = IPR_MIDIRECVBUFEMPTY;
	midi->interrupt = snd_emu10k1_midi_interrupt;

	midi = &emu->midi2;
	if ((err = emu10k1_midi_init(emu, midi, 1, "Audigy MPU-401 #2")) < 0)
	return err;

	midi->tx_enable = INTE_A_MIDITXENABLE2;
	midi->rx_enable = INTE_A_MIDIRXENABLE2;
	midi->port = A_MUDATA2;
	midi->ipr_tx = IPR_A_MIDITRANSBUFEMPTY2;
	midi->ipr_rx = IPR_A_MIDIRECVBUFEMPTY2;
	midi->interrupt = snd_emu10k1_midi_interrupt2;
	return 0;
	}