started to split out the midi drivers

svn-id: r5889

4 files changed, 219 insertions, 546 deletions

diff --git a/sound/mididrv.cpp b/sound/mididrv.cpp
index ce379a51c6..c13cb8e0f5 100644
--- a/sound/mididrv.cpp
+++ b/sound/mididrv.cpp
@@ -20,8 +20,6 @@
  */
 
 /*
- * Timidity support by Lionel Ulmer <lionel.ulmer@free.fr>
- * QuickTime support by Florent Boudet <flobo@ifrance.com>
  * Raw output support by Michael Pearce
  * MorphOS support by Ruediger Hanke 
  * Alsa support by Nicolas Noble <nicolas@nobis-crew.org> copied from
@@ -30,170 +28,35 @@
 
 #include "stdafx.h"
 #include "mididrv.h"
-#include "fmopl.h"
-#include "mixer.h"
+#include "mpu401.h"
 #include "common/engine.h"	// for warning/error/debug
-#include "common/util.h"
+#include "common/util.h"	// for ARRAYSIZE
 
 
 
-////////////////////////////////////////
-//
-// Common MPU401 implementation methods
-//
-////////////////////////////////////////
-
-typedef void TimerCallback (void *);
-
-class MidiDriver_MPU401;
-
-class MidiChannel_MPU401 : public MidiChannel {
-	friend class MidiDriver_MPU401;
-
-private:
-	MidiDriver_MPU401 *_owner;
-	bool _allocated;
-	byte _channel;
-
-	void init (MidiDriver_MPU401 *owner, byte channel);
-	void allocate() { _allocated = true; }
-
-public:
-	void release() { _allocated = false; }
-
-	// Regular messages
-	void noteOff (byte note);
-	void noteOn (byte note, byte velocity);
-	void programChange (byte program);
-	void pitchBend (int16 bend);
-
-	// Control Change messages
-	void controlChange (byte control, byte value);
-	void modulationWheel (byte value) { controlChange (1, value); }
-	void volume (byte value) { controlChange (7, value); }
-	void panPosition (byte value) { controlChange (10, value); }
-	void pitchBendFactor (byte value);
-	void detune (byte value) { controlChange (17, value); }
-	void priority (byte value) { controlChange (18, value); }
-	void sustain (bool value) { controlChange (64, value ? 1 : 0); }
-	void effectLevel (byte value) { controlChange (91, value); }
-	void chorusLevel (byte value) { controlChange (93, value); }
-	void allNotesOff() { controlChange (123, 0); }
-
-	// SysEx messages
-	void sysEx_customInstrument (uint32 type, byte *instr);
-};
-
-
-
-class MidiDriver_MPU401 : public MidiDriver {
-private:
-	MidiChannel_MPU401 _midi_channels [16];
-	bool _started_thread;
-	TimerCallback *_timer_proc;
-	void *_timer_param;
-
-	static int midi_driver_thread (void *param);
-
-public:
-	MidiDriver_MPU401();
-
-	virtual void setTimerCallback (void *timer_param, void (*timer_proc) (void *));
-	virtual uint32 getBaseTempo (void) { return 0x4A0000; }
-
-	virtual MidiChannel *allocateChannel();
-	virtual MidiChannel *getPercussionChannel() { return &_midi_channels [9]; }
-};
-
-
-
-void MidiChannel_MPU401::init (MidiDriver_MPU401 *owner, byte channel)
-{
-	_owner = owner;
-	_channel = channel;
-	_allocated = false;
-}
-
-void MidiChannel_MPU401::noteOff (byte note) { _owner->send(note << 8 | 0x80 | _channel); }
-void MidiChannel_MPU401::noteOn (byte note, byte velocity) { _owner->send (velocity << 16 | note << 8 | 0x90 | _channel); }
-void MidiChannel_MPU401::programChange (byte program) { _owner->send(program << 8 | 0xC0 | _channel); }
-void MidiChannel_MPU401::pitchBend (int16 bend) { _owner->send((((bend + 0x2000) >> 7) & 0x7F) << 16 | ((bend + 0x2000) & 0x7F) << 8 | 0xE0 | _channel); }
-void MidiChannel_MPU401::controlChange (byte control, byte value) { _owner->send(value << 16 | control << 8 | 0xB0 | _channel); }
-void MidiChannel_MPU401::pitchBendFactor (byte value) { _owner->setPitchBendRange (_channel, value); }
-void MidiChannel_MPU401::sysEx_customInstrument (uint32 type, byte *instr) { _owner->sysEx_customInstrument (_channel, type, instr); }
-
-
-
-MidiDriver_MPU401::MidiDriver_MPU401() : MidiDriver()
-{
-	uint i;
-	for (i = 0; i < ARRAYSIZE(_midi_channels); ++i) {
-		_midi_channels [i].init (this, i);
-	}
-}
-
-
-
-MidiChannel *MidiDriver_MPU401::allocateChannel()
+/* Default (empty) property method */
+uint32 MidiDriver::property(int prop, uint32 param)
 {
-	MidiChannel_MPU401 *chan;
-	uint i;
-	
-	for (i = 0; i < ARRAYSIZE(_midi_channels); ++i) {
-		if (i == 9) continue;
-		chan = &_midi_channels[i];
-		if (!chan->_allocated) {
-			chan->allocate();
-			return (chan);
-		}
-	}
-	return NULL;
+	return 0;
 }
 
 
-void MidiDriver_MPU401::setTimerCallback (void *timer_param, void (*timer_proc) (void *))
-{
-	if (!_timer_proc || !timer_proc) {
-		_timer_proc = (TimerCallback *) timer_proc;
-		_timer_param = timer_param;
-		if (!_started_thread && timer_proc)
-			g_system->create_thread (midi_driver_thread, this);
-		_started_thread = true;
-	}
-}
-
-int MidiDriver_MPU401::midi_driver_thread(void *param)
+/* retrieve a string representation of an error code */
+const char *MidiDriver::get_error_name(int error_code)
 {
-	MidiDriver_MPU401 *mid = (MidiDriver_MPU401 *)param;
-	int old_time, cur_time;
-	
-	old_time = g_system->get_msecs();
-
-	for (;;) {
-		g_system->delay_msecs(10);
-
-		cur_time = g_system->get_msecs();
-		while (old_time < cur_time) {
-			old_time += 10;
-			// Don't use mid->_se_on_timer()
-			// We must come in through IMuseMonitor to protect
-			// against conflicts with script access to IMuse.
-			if (mid->_timer_proc)
-				(*(mid->_timer_proc)) (mid->_timer_param);
-		}
-	}
+	static const char *const midi_errors[] = {
+		"No error",
+		"Cannot connect",
+		"Streaming not available",
+		"Device not available",
+		"Driver already open"
+	};
 
-	return 0;
+	if ((uint) error_code >= ARRAYSIZE(midi_errors))
+		return "Unknown Error";
+	return midi_errors[error_code];
 }
 
-
-
-// FIXME - the following disables reverb support in the QuickTime / CoreAudio
-// midi backends. For some reasons, reverb will suck away a *lot* of CPU time.
-// Until we know for sure what is causing this and if there is a better way to
-// fix the problem, we just disable all reverb for these backends.
-#define COREAUDIO_REVERB_HACK
-
 #if defined(WIN32) && !defined(_WIN32_WCE)
 
 /* Windows MIDI driver */
@@ -792,397 +655,6 @@ MidiDriver *MidiDriver_SEQ_create()
 
 #endif
 
-#if defined(__APPLE__) || defined(macintosh)
-// FIXME - this is for Mac OS X and Mac OS 9. It's not really possible
-// to check for these *cleanly* without a configure script, though..
-
-
-#if defined(MACOSX)
- // On MacOSX, these are in a frameworks!
-#include <QuickTime/QuickTimeComponents.h>
-#include <QuickTime/QuickTimeMusic.h>
-#else
-#include <QuickTimeComponents.h>
-#include <QuickTimeMusic.h>
-#endif
-
-
-/* QuickTime MIDI driver */
-class MidiDriver_QT:public MidiDriver_MPU401 {
-public:
-	int open(int mode);
-	void close();
-	void send(uint32 b);
-	void pause(bool p) { }
-	void set_stream_callback(void *param, StreamCallback *sc);
-	void setPitchBendRange (byte channel, uint range);
-
-private:
-	NoteAllocator qtNoteAllocator;
-	NoteChannel qtNoteChannel[16];
-	NoteRequest simpleNoteRequest;
-
-	StreamCallback *_stream_proc;
-	void *_stream_param;
-	int _mode;
-
-	// Pitch bend tracking. Necessary since QTMA handles
-	// pitch bending so differently from MPU401.
-	uint16 _pitchbend [16];
-	byte _pitchbend_range [16];
-};
-
-void MidiDriver_QT::set_stream_callback(void *param, StreamCallback *sc)
-{
-	_stream_param = param;
-	_stream_proc = sc;
-}
-
-int MidiDriver_QT::open(int mode)
-{
-	ComponentResult qtErr = noErr;
-	int i;
-
-	qtNoteAllocator = NULL;
-
-	if (mode == MO_STREAMING)
-		return MERR_STREAMING_NOT_AVAILABLE;
-
-	_mode = mode;
-
-	for (i = 0; i < 15; i++)
-		qtNoteChannel[i] = NULL;
-
-	qtNoteAllocator = OpenDefaultComponent(kNoteAllocatorComponentType, 0);
-	if (qtNoteAllocator == NULL)
-		goto bail;
-
-	simpleNoteRequest.info.flags = 0;
-	*(short *)(&simpleNoteRequest.info.polyphony) = EndianS16_NtoB(15);	// simultaneous tones
-	*(Fixed *) (&simpleNoteRequest.info.typicalPolyphony) = EndianU32_NtoB(0x00010000);
-
-	qtErr = NAStuffToneDescription(qtNoteAllocator, 1, &simpleNoteRequest.tone);
-	if (qtErr != noErr)
-		goto bail;
-
-	for (i = 0; i < 15; i++) {
-		qtErr = NANewNoteChannel(qtNoteAllocator, &simpleNoteRequest, &(qtNoteChannel[i]));
-		if ((qtErr != noErr) || (qtNoteChannel == NULL))
-			goto bail;
-	}
-	return 0;
-
-bail:
-	error("Init QT failed %x %x %d\n", (int)qtNoteAllocator, (int)qtNoteChannel, (int)qtErr);
-	for (i = 0; i < 15; i++) {
-		if (qtNoteChannel[i] != NULL)
-			NADisposeNoteChannel(qtNoteAllocator, qtNoteChannel[i]);
-		qtNoteChannel[i] = NULL;
-	}
-
-	if (qtNoteAllocator != NULL) {
-		CloseComponent(qtNoteAllocator);
-		qtNoteAllocator = NULL;
-	}
-
-	return MERR_DEVICE_NOT_AVAILABLE;
-}
-
-void MidiDriver_QT::close()
-{
-	_mode = 0;
-
-	for (int i = 0; i < 15; i++) {
-		if (qtNoteChannel[i] != NULL)
-			NADisposeNoteChannel(qtNoteAllocator, qtNoteChannel[i]);
-		qtNoteChannel[i] = NULL;
-	}
-
-	if (qtNoteAllocator != NULL) {
-		CloseComponent(qtNoteAllocator);
-		qtNoteAllocator = NULL;
-	}
-}
-
-void MidiDriver_QT::send(uint32 b)
-{
-	if (_mode != MO_SIMPLE)
-		error("MidiDriver_QT:send called but driver is not in simple mode");
-
-	MusicMIDIPacket midPacket;
-	unsigned char *midiCmd = midPacket.data;
-	midPacket.length = 3;
-	midiCmd[3] = (b & 0xFF000000) >> 24;
-	midiCmd[2] = (b & 0x00FF0000) >> 16;
-	midiCmd[1] = (b & 0x0000FF00) >> 8;
-	midiCmd[0] = (b & 0x000000FF);
-
-	unsigned char chanID = midiCmd[0] & 0x0F;
-	switch (midiCmd[0] & 0xF0) {
-	case 0x80:										// Note off
-		NAPlayNote(qtNoteAllocator, qtNoteChannel[chanID], midiCmd[1], 0);
-		break;
-
-	case 0x90:										// Note on
-		NAPlayNote(qtNoteAllocator, qtNoteChannel[chanID], midiCmd[1], midiCmd[2]);
-		break;
-
-	case 0xB0:										// Effect
-		switch (midiCmd[1]) {
-		case 0x01:									// Modulation
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID],
-											kControllerModulationWheel, midiCmd[2] << 8);
-			break;
-
-		case 0x07:									// Volume
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID], kControllerVolume, midiCmd[2] * 300);
-			break;
-
-		case 0x0A:									// Pan
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID], kControllerPan,
-											(midiCmd[2] << 1) + 0xFF);
-			break;
-
-		case 0x40:									// Sustain on/off
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID], kControllerSustain, midiCmd[2]);
-			break;
-
-		case 0x5b:									// ext effect depth
-#if !defined(COREAUDIO_REVERB_HACK)
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID], kControllerReverb, midiCmd[2] << 8);
-#endif
-			break;
-
-		case 0x5d:									// chorus depth
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID], kControllerChorus, midiCmd[2] << 8);
-			break;
-
-		case 0x7b:									// mode message all notes off
-			for (int i = 0; i < 128; i++)
-				NAPlayNote(qtNoteAllocator, qtNoteChannel[chanID], i, 0);
-			break;
-		case 0x64:
-		case 0x65:
-		case 0x06:
-		case 0x26:
-			// pitch bend changes - ignore those for now
-			break;
-
-		case 0x12:	// Occurs in Scumm games
-		case 0x79:	// Occurs in Simon1
-			// What are these ?!? Ignore it for now
-			break;
-
-		default:
-			// Error: Unknown MIDI effect: 007f76b3
-			warning("Unknown MIDI effect: %08x", (int)b);
-			break;
-		}
-		break;
-
-	case 0xC0:										// Program change
-		NASetInstrumentNumber(qtNoteAllocator, qtNoteChannel[chanID], midiCmd[1] + 1);
-		break;
-
-	case 0xE0:{									// Pitch bend
-			// QuickTime specifies pitchbend in semitones, using 8.8 fixed point values;
-			// but iMuse sends us the pitch bend data as 0-16383. which has to be mapped
-			// to +/- 12 semitones. Based on this, we first center the input data, then
-			// multiply it by a factor. If all was right, the factor would be 3/8, but for
-			// mysterious reasons the actual factor we have to use is more like 1/32 or 3/64.
-			// Maybe the QT docs are right, and 
-			_pitchbend[chanID] = ((uint16) midiCmd[1] | (uint16) (midiCmd[2] << 7));
- 			long theBend = ((long) _pitchbend[chanID] - 0x2000) * _pitchbend_range[chanID] / 32;
-
-			NASetController(qtNoteAllocator, qtNoteChannel[chanID], kControllerPitchBend, theBend);
-		}
-		break;
-
-	default:
-		error("Unknown Command: %08x", (int)b);
-		NASendMIDI(qtNoteAllocator, qtNoteChannel[chanID], &midPacket);
-		break;
-	}
-}
-
-void MidiDriver_QT::setPitchBendRange (byte channel, uint range)
-{
-	if (_pitchbend_range[channel] == range)
-		return;
-	_pitchbend_range[channel] = range;
-
-	long theBend = _pitchbend[channel];
-	theBend = (theBend - 0x2000) * range / 32;
-	NASetController(qtNoteAllocator, qtNoteChannel[channel], kControllerPitchBend, theBend);
-}
-
-MidiDriver *MidiDriver_QT_create()
-{
-	return new MidiDriver_QT();
-}
-
-#endif // __APPLE__ || macintosh
-
-
-#ifdef __APPLE__
-
-#include <AudioUnit/AudioUnit.h>
-
-/* CoreAudio MIDI driver */
-/* Based on code by Benjamin W. Zale */
-class MidiDriver_CORE:public MidiDriver_MPU401 {
-public:
-	MidiDriver_CORE():au_MusicDevice(NULL), au_output(NULL) {
-	} int open(int mode);
-	void close();
-	void send(uint32 b);
-	void pause(bool p);
-	void set_stream_callback(void *param, StreamCallback *sc);
-	// void setPitchBendRange (byte channel, uint range);
-
-private:
-	AudioUnit au_MusicDevice;
-	AudioUnit au_output;
-
-	int _mode;
-};
-
-
-void MidiDriver_CORE::set_stream_callback(void *param, StreamCallback *sc)
-{
-}
-
-
-int MidiDriver_CORE::open(int mode)
-{
-	if (au_output != NULL)
-		return MERR_ALREADY_OPEN;
-
-	if (mode == MO_STREAMING)
-		return MERR_STREAMING_NOT_AVAILABLE;
-
-	_mode = mode;
-
-	int err;
-	AudioUnitConnection auconnect;
-	ComponentDescription compdesc;
-	Component compid;
-
-	// Open the Music Device
-	compdesc.componentType = kAudioUnitComponentType;
-	compdesc.componentSubType = kAudioUnitSubType_MusicDevice;
-	compdesc.componentManufacturer = kAudioUnitID_DLSSynth;
-	compdesc.componentFlags = 0;
-	compdesc.componentFlagsMask = 0;
-	compid = FindNextComponent(NULL, &compdesc);
-	au_MusicDevice = (AudioUnit) OpenComponent(compid);
-
-	// open the output unit
-	au_output = (AudioUnit) OpenDefaultComponent(kAudioUnitComponentType, kAudioUnitSubType_Output);
-
-	// connect the units
-	auconnect.sourceAudioUnit = au_MusicDevice;
-	auconnect.sourceOutputNumber = 0;
-	auconnect.destInputNumber = 0;
-	err =
-		AudioUnitSetProperty(au_output, kAudioUnitProperty_MakeConnection, kAudioUnitScope_Input, 0,
-												 (void *)&auconnect, sizeof(AudioUnitConnection));
-
-	// initialize the units
-	AudioUnitInitialize(au_MusicDevice);
-	AudioUnitInitialize(au_output);
-
-	// start the output
-	AudioOutputUnitStart(au_output);
-
-	return 0;
-}
-
-void MidiDriver_CORE::close()
-{
-	// Stop the output
-	AudioOutputUnitStop(au_output);
-
-	// Cleanup
-	CloseComponent(au_output);
-	CloseComponent(au_MusicDevice);
-
-	_mode = 0;
-}
-
-void MidiDriver_CORE::send(uint32 b)
-{
-	unsigned char first_byte, seccond_byte, status_byte;
-	status_byte = (b & 0x000000FF);
-	first_byte = (b & 0x0000FF00) >> 8;
-	seccond_byte = (b & 0x00FF0000) >> 16;
-
-#ifdef COREAUDIO_REVERB_HACK
-	if ((status_byte&0xF0) == 0xB0 && first_byte == 0x5b)
-		return;
-#endif
-
-	MusicDeviceMIDIEvent(au_MusicDevice, status_byte, first_byte, seccond_byte, 0);
-}
-
-void MidiDriver_CORE::pause(bool)
-{
-}
-
-MidiDriver *MidiDriver_CORE_create()
-{
-	return new MidiDriver_CORE();
-}
-
-#endif // __APPLE__
-
-/* NULL driver */
-class MidiDriver_NULL:public MidiDriver_MPU401 {
-public:
-	int open(int mode);
-	void close() { }
-	void send(uint32 b) { }
-	void pause(bool p) { }
-	void set_stream_callback(void *param, StreamCallback *sc) { }
-	// void setPitchBendRange (byte channel, uint range);
-private:
-};
-
-int MidiDriver_NULL::open(int mode)
-{
-	warning("Music not enabled - MIDI support selected with no MIDI driver available. Try Adlib");
-	return 0;
-}
-
-MidiDriver *MidiDriver_NULL_create()
-{
-	return new MidiDriver_NULL();
-}
-
-
-
-/* Default (empty) property method */
-uint32 MidiDriver::property(int prop, uint32 param)
-{
-	return 0;
-}
-
-
-/* retrieve a string representation of an error code */
-const char *MidiDriver::get_error_name(int error_code)
-{
-	static const char *const midi_errors[] = {
-		"No error",
-		"Cannot connect",
-		"Streaming not available",
-		"Device not available",
-		"Driver already open"
-	};
-
-	if ((uint) error_code >= ARRAYSIZE(midi_errors))
-		return "Unknown Error";
-	return midi_errors[error_code];
-}
 
 #if defined(UNIX) && defined(USE_ALSA)
 
diff --git a/sound/module.mk b/sound/module.mk
index 41abc334f7..1e066a5837 100644
--- a/sound/module.mk
+++ b/sound/module.mk
@@ -4,7 +4,8 @@ MODULE_OBJS = \
 	sound/fmopl.o \
 	sound/mididrv.o \
 	sound/midistreamer.o \
-	sound/mixer.o
+	sound/mixer.o \
+	sound/mpu401.o
 
 # Include common rules 
 include common.rules
diff --git a/sound/mpu401.cpp b/sound/mpu401.cpp
new file mode 100644
index 0000000000..f2e2ca5e9e
--- /dev/null
+++ b/sound/mpu401.cpp
@@ -0,0 +1,104 @@
+/* ScummVM - Scumm Interpreter
+ * Copyright (C) 2001/2002 The ScummVM project
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * $Header$
+ */
+
+#include "stdafx.h"
+#include "mpu401.h"
+#include "common/engine.h"	// for g_system
+#include "common/util.h"	// for ARRAYSIZE
+
+
+void MidiChannel_MPU401::init (MidiDriver_MPU401 *owner, byte channel)
+{
+	_owner = owner;
+	_channel = channel;
+	_allocated = false;
+}
+
+void MidiChannel_MPU401::noteOff (byte note) { _owner->send(note << 8 | 0x80 | _channel); }
+void MidiChannel_MPU401::noteOn (byte note, byte velocity) { _owner->send (velocity << 16 | note << 8 | 0x90 | _channel); }
+void MidiChannel_MPU401::programChange (byte program) { _owner->send(program << 8 | 0xC0 | _channel); }
+void MidiChannel_MPU401::pitchBend (int16 bend) { _owner->send((((bend + 0x2000) >> 7) & 0x7F) << 16 | ((bend + 0x2000) & 0x7F) << 8 | 0xE0 | _channel); }
+void MidiChannel_MPU401::controlChange (byte control, byte value) { _owner->send(value << 16 | control << 8 | 0xB0 | _channel); }
+void MidiChannel_MPU401::pitchBendFactor (byte value) { _owner->setPitchBendRange (_channel, value); }
+void MidiChannel_MPU401::sysEx_customInstrument (uint32 type, byte *instr) { _owner->sysEx_customInstrument (_channel, type, instr); }
+
+
+MidiDriver_MPU401::MidiDriver_MPU401() : MidiDriver()
+{
+	uint i;
+	for (i = 0; i < ARRAYSIZE(_midi_channels); ++i) {
+		_midi_channels [i].init (this, i);
+	}
+}
+
+
+
+MidiChannel *MidiDriver_MPU401::allocateChannel()
+{
+	MidiChannel_MPU401 *chan;
+	uint i;
+	
+	for (i = 0; i < ARRAYSIZE(_midi_channels); ++i) {
+		if (i == 9) continue;
+		chan = &_midi_channels[i];
+		if (!chan->_allocated) {
+			chan->allocate();
+			return (chan);
+		}
+	}
+	return NULL;
+}
+
+
+void MidiDriver_MPU401::setTimerCallback (void *timer_param, void (*timer_proc) (void *))
+{
+	if (!_timer_proc || !timer_proc) {
+		_timer_proc = (TimerCallback *) timer_proc;
+		_timer_param = timer_param;
+		if (!_started_thread && timer_proc)
+			g_system->create_thread (midi_driver_thread, this);
+		_started_thread = true;
+	}
+}
+
+int MidiDriver_MPU401::midi_driver_thread(void *param)
+{
+	MidiDriver_MPU401 *mid = (MidiDriver_MPU401 *)param;
+	int old_time, cur_time;
+	
+	old_time = g_system->get_msecs();
+
+	for (;;) {
+		g_system->delay_msecs(10);
+
+		cur_time = g_system->get_msecs();
+		while (old_time < cur_time) {
+			old_time += 10;
+			// Don't use mid->_se_on_timer()
+			// We must come in through IMuseMonitor to protect
+			// against conflicts with script access to IMuse.
+			if (mid->_timer_proc)
+				(*(mid->_timer_proc)) (mid->_timer_param);
+		}
+	}
+
+	return 0;
+}
+
diff --git a/sound/mpu401.h b/sound/mpu401.h
new file mode 100644
index 0000000000..4de50b6418
--- /dev/null
+++ b/sound/mpu401.h
@@ -0,0 +1,96 @@
+/* ScummVM - Scumm Interpreter
+ * Copyright (C) 2001/2002 The ScummVM project
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * $Header$
+ *
+ */
+
+#ifndef SOUND_MPU401_H
+#define SOUND_MPU401_H
+
+#include "mididrv.h"
+
+////////////////////////////////////////
+//
+// Common MPU401 implementation methods
+//
+////////////////////////////////////////
+
+typedef void TimerCallback (void *);
+
+class MidiDriver_MPU401;
+
+class MidiChannel_MPU401 : public MidiChannel {
+	friend class MidiDriver_MPU401;
+
+private:
+	MidiDriver_MPU401 *_owner;
+	bool _allocated;
+	byte _channel;
+
+	void init (MidiDriver_MPU401 *owner, byte channel);
+	void allocate() { _allocated = true; }
+
+public:
+	void release() { _allocated = false; }
+
+	// Regular messages
+	void noteOff (byte note);
+	void noteOn (byte note, byte velocity);
+	void programChange (byte program);
+	void pitchBend (int16 bend);
+
+	// Control Change messages
+	void controlChange (byte control, byte value);
+	void modulationWheel (byte value) { controlChange (1, value); }
+	void volume (byte value) { controlChange (7, value); }
+	void panPosition (byte value) { controlChange (10, value); }
+	void pitchBendFactor (byte value);
+	void detune (byte value) { controlChange (17, value); }
+	void priority (byte value) { controlChange (18, value); }
+	void sustain (bool value) { controlChange (64, value ? 1 : 0); }
+	void effectLevel (byte value) { controlChange (91, value); }
+	void chorusLevel (byte value) { controlChange (93, value); }
+	void allNotesOff() { controlChange (123, 0); }
+
+	// SysEx messages
+	void sysEx_customInstrument (uint32 type, byte *instr);
+};
+
+
+
+class MidiDriver_MPU401 : public MidiDriver {
+private:
+	MidiChannel_MPU401 _midi_channels [16];
+	bool _started_thread;
+	TimerCallback *_timer_proc;
+	void *_timer_param;
+
+	static int midi_driver_thread (void *param);
+
+public:
+	MidiDriver_MPU401();
+
+	virtual void setTimerCallback (void *timer_param, void (*timer_proc) (void *));
+	virtual uint32 getBaseTempo (void) { return 0x4A0000; }
+
+	virtual MidiChannel *allocateChannel();
+	virtual MidiChannel *getPercussionChannel() { return &_midi_channels [9]; }
+};
+
+
+#endif