Initial OPNMIDI integration

Config.mk

@@ -96,4 +96,8 @@ LIBADLMIDIHOME=$(realpath external/libadlmidi)
 LIBADLMIDIBUILDDIR=build-libadlmidi
 LIBADLMIDILIB=$(LIBADLMIDIBUILDDIR)/libADLMIDI.a
 
+LIBOPNMIDIHOME=$(realpath external/libopnmidi)
+LIBOPNMIDIBUILDDIR=build-libopnmidi
+LIBOPNMIDILIB=$(LIBOPNMIDIBUILDDIR)/libOPNMIDI.a
+
 INIHHOME=$(realpath external/inih)

Kernel.mk

@@ -31,6 +31,7 @@ OBJS		:=	src/config.o \
 			src/soundfontmanager.o \
 			src/synth/mt32synth.o \
 			src/synth/oplsynth.o \
+			src/synth/opnsynth.o \
 			src/synth/soundfontsynth.o \
 			src/synth/synthbase.o \
 			src/zoneallocator.o
@@ -89,6 +90,9 @@ EXTRALIBS	+=	$(FLUIDSYNTHLIB)
 INCLUDE		+=	-I $(LIBADLMIDIHOME)/include
 EXTRALIBS	+=	$(LIBADLMIDILIB)
 
+INCLUDE		+=	-I $(LIBOPNMIDIHOME)/include
+EXTRALIBS	+=	$(LIBOPNMIDILIB)
+
 #
 # Generate version string from git tag
 #

Makefile

@@ -150,10 +150,28 @@ $(LIBADLMIDIBUILDDIR)/.done: $(CIRCLESTDLIBHOME)/.done
 	@cmake --build $(LIBADLMIDIBUILDDIR) --target ADLMIDI_static
 	@touch $@
 
+#
+# Build libOPNMIDI
+#
+libopnmidi: $(LIBOPNMIDIBUILDDIR)/.done
+
+$(LIBOPNMIDIBUILDDIR)/.done: $(CIRCLESTDLIBHOME)/.done
+	@CFLAGS="$(CFLAGS_EXTERNAL)" \
+	CXXFLAGS="$(CFLAGS_EXTERNAL)" \
+	cmake  -B $(LIBOPNMIDIBUILDDIR) \
+		   $(CMAKE_TOOLCHAIN_FLAGS) \
+		  	-DCMAKE_BUILD_TYPE=Release \
+		  	-DWITH_MIDI_SEQUENCER=OFF \
+		  	-DUSE_VGM_FILE_DUMPER=OFF \
+		  	$(LIBOPNMIDIHOME) \
+		  	>/dev/null
+	@cmake --build $(LIBOPNMIDIBUILDDIR) --target OPNMIDI_static
+	@touch $@
+
 #
 # Build kernel itself
 #
-all: circle-stdlib mt32emu fluidsynth libadlmidi
+all: circle-stdlib mt32emu fluidsynth libadlmidi libopnmidi
 	@$(MAKE) -f Kernel.mk $(KERNEL).img $(KERNEL).hex
 
 #
@@ -183,3 +201,6 @@ mrproper: clean
 
 # Clean libADLMIDI
 	@$(RM) -r $(LIBADLMIDIBUILDDIR)
+
+# Clean libOPNMIDI
+	@$(RM) -r $(LIBOPNMIDIBUILDDIR)

include/config.h

@@ -38,7 +38,8 @@ public:
 	#define ENUM_SYSTEMDEFAULTSYNTH(ENUM) \
 		ENUM(MT32, mt32)              \
 		ENUM(SoundFont, soundfont)    \
-		ENUM(OPL, opl)
+		ENUM(OPL, opl)                \
+		ENUM(OPN, opn)
 
 	#define ENUM_AUDIOOUTPUTDEVICE(ENUM) \
 		ENUM(PWM, pwm)                   \

include/mt32pi.h

@@ -62,6 +62,7 @@
 #include "synth/mt32romset.h"
 #include "synth/mt32synth.h"
 #include "synth/oplsynth.h"
+#include "synth/opnsynth.h"
 #include "synth/soundfontsynth.h"
 #include "synth/synth.h"
 
@@ -114,6 +115,7 @@ private:
 	bool InitMT32Synth();
 	bool InitSoundFontSynth();
 	bool InitOPLSynth();
+	bool InitOPNSynth();
 
 	// Tasks for specific CPU cores
 	void MainTask();
@@ -216,6 +218,7 @@ private:
 	CMT32Synth* m_pMT32Synth;
 	CSoundFontSynth* m_pSoundFontSynth;
 	COPLSynth* m_pOPLSynth;
+	COPNSynth* m_pOPNSynth;
 
 	// MIDI receive buffer
 	CRingBuffer<u8, MIDIRxBufferSize> m_MIDIRxBuffer;

include/synth/opnsynth.h

@@ -0,0 +1,55 @@
+//
+// opnsynth.h
+//
+// mt32-pi - A baremetal MIDI synthesizer for Raspberry Pi
+// Copyright (C) 2020-2022 Dale Whinham <daleyo@gmail.com>
+//
+// This file is part of mt32-pi.
+//
+// mt32-pi 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 3 of the License, or (at your option) any later
+// version.
+//
+// mt32-pi 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
+// mt32-pi. If not, see <http://www.gnu.org/licenses/>.
+//
+
+#ifndef _opnsynth_h
+#define _opnsynth_h
+
+#include <circle/types.h>
+
+#include <opnmidi.h>
+
+#include "synth/synthbase.h"
+
+class COPNSynth : public CSynthBase
+{
+public:
+	COPNSynth(unsigned nSampleRate);
+	virtual ~COPNSynth() override;
+
+	// CSynthBase
+	virtual bool Initialize() override;
+	virtual void HandleMIDIShortMessage(u32 nMessage) override;
+	virtual void HandleMIDISysExMessage(const u8* pData, size_t nSize) override;
+	virtual bool IsActive() override;
+	virtual void AllSoundOff() override;
+	virtual void SetMasterVolume(u8 nVolume) override;
+	virtual size_t Render(s16* pOutBuffer, size_t nFrames) override;
+	virtual size_t Render(float* pOutBuffer, size_t nFrames) override;
+	virtual void ReportStatus() const override;
+
+private:
+	OPN2_MIDIPlayer* m_pSynth;
+
+	u8 m_nVolume;
+};
+
+#endif

include/synth/synth.h

@@ -28,6 +28,7 @@ enum class TSynth
 	MT32,
 	SoundFont,
 	OPL,
+	OPN,
 };
 
 #endif

sdcard/mt32-pi.cfg

@@ -34,6 +34,7 @@ verbose = off
 # mt32:      Use mt32emu (Munt) for Roland MT-32 emulation
 # soundfont: Use FluidSynth for SoundFont synthesis
 # opl: 	     Use ADLMIDI for Yamaha OPL synthesis
+# opn: 	     Use OPNMIDI for Yamaha OPN synthesis
 default_synth = mt32
 
 # Enable or disable support for USB devices.

src/mt32pi.cpp

@@ -121,7 +121,8 @@ CMT32Pi::CMT32Pi(CI2CMaster* pI2CMaster, CSPIMaster* pSPIMaster, CInterruptSyste
 	  m_pCurrentSynth(nullptr),
 	  m_pMT32Synth(nullptr),
 	  m_pSoundFontSynth(nullptr),
-	  m_pOPLSynth(nullptr)
+	  m_pOPLSynth(nullptr),
+	  m_pOPNSynth(nullptr)
 {
 	s_pThis = this;
 }
@@ -280,6 +281,9 @@ bool CMT32Pi::Initialize(bool bSerialMIDIAvailable)
 	LCDLog(TLCDLogType::Startup, "Init ADLMIDI");
 	InitOPLSynth();
 
+	LCDLog(TLCDLogType::Startup, "Init OPNMIDI");
+	InitOPNSynth();
+
 	// Set initial synthesizer
 	if (m_pConfig->SystemDefaultSynth == CConfig::TSystemDefaultSynth::MT32)
 		m_pCurrentSynth = m_pMT32Synth;
@@ -287,6 +291,8 @@ bool CMT32Pi::Initialize(bool bSerialMIDIAvailable)
 		m_pCurrentSynth = m_pSoundFontSynth;
 	else if (m_pConfig->SystemDefaultSynth == CConfig::TSystemDefaultSynth::OPL)
 		m_pCurrentSynth = m_pOPLSynth;
+	else if (m_pConfig->SystemDefaultSynth == CConfig::TSystemDefaultSynth::OPN)
+		m_pCurrentSynth = m_pOPNSynth;
 
 	if (!m_pCurrentSynth)
 	{
@@ -299,6 +305,8 @@ bool CMT32Pi::Initialize(bool bSerialMIDIAvailable)
 			m_pCurrentSynth = m_pSoundFontSynth;
 		else if (m_pOPLSynth)
 			m_pCurrentSynth = m_pOPLSynth;
+		else if (m_pOPNSynth)
+			m_pCurrentSynth = m_pOPNSynth;
 		else
 		{
 			m_pLogger->Write(MT32PiName, LogPanic, "No synths available; ROMs/SoundFonts not found");
@@ -437,6 +445,24 @@ bool CMT32Pi::InitOPLSynth()
 	return true;
 }
 
+bool CMT32Pi::InitOPNSynth()
+{
+	assert(m_pOPNSynth == nullptr);
+
+	m_pOPNSynth = new COPNSynth(m_pConfig->AudioSampleRate);
+	if (!m_pOPNSynth->Initialize())
+	{
+		m_pLogger->Write(MT32PiName, LogWarning, "OPNMIDI init failed; no banks present?");
+		delete m_pOPNSynth;
+		m_pOPNSynth = nullptr;
+		return false;
+	}
+
+	m_pOPNSynth->SetUserInterface(&m_UserInterface);
+
+	return true;
+}
+
 void CMT32Pi::MainTask()
 {
 	CScheduler* const pScheduler = CScheduler::Get();
@@ -1101,6 +1127,8 @@ void CMT32Pi::ProcessButtonEvent(const TButtonEvent& Event)
 			SwitchSynth(TSynth::SoundFont);
 		else if (m_pCurrentSynth == m_pSoundFontSynth)
 			SwitchSynth(TSynth::OPL);
+		else if (m_pCurrentSynth == m_pOPLSynth)
+			SwitchSynth(TSynth::OPN);
 		else
 			SwitchSynth(TSynth::MT32);
 	}
@@ -1165,6 +1193,11 @@ void CMT32Pi::SwitchSynth(TSynth NewSynth)
 			pNewSynth = m_pOPLSynth;
 			pModeString = "OPL mode";
 			break;
+
+		case TSynth::OPN:
+			pNewSynth = m_pOPNSynth;
+			pModeString = "OPN mode";
+			break;
 	}
 
 	if (pNewSynth == nullptr)
@@ -1244,6 +1277,8 @@ void CMT32Pi::SetMasterVolume(s32 nVolume)
 		m_pSoundFontSynth->SetMasterVolume(m_nMasterVolume);
 	if (m_pOPLSynth)
 		m_pOPLSynth->SetMasterVolume(m_nMasterVolume);
+	if (m_pOPNSynth)
+		m_pOPNSynth->SetMasterVolume(m_nMasterVolume);
 
 	if (m_pCurrentSynth != m_pMT32Synth)
 		LCDLog(TLCDLogType::Notice, "Volume: %d", m_nMasterVolume);