From 8c875845a79e20b12dfee6d1dea5bf0e0dc0834f Mon Sep 17 00:00:00 2001
From: hap <happppp@users.noreply.github.com>
Date: Sun, 4 Nov 2018 16:14:07 +0100
Subject: [PATCH] k054321: remember initial speaker input gains, this fixes
 volume balance in xmen (nw)

---
 src/devices/machine/k054321.cpp | 34 +++++++++++++++++++++++++--------
 src/devices/machine/k054321.h   |  3 +++
 src/mame/drivers/rungun.cpp     |  4 ++--
 3 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/src/devices/machine/k054321.cpp b/src/devices/machine/k054321.cpp
index a47addbafb5..21e02e9042f 100644
--- a/src/devices/machine/k054321.cpp
+++ b/src/devices/machine/k054321.cpp
@@ -56,15 +56,29 @@ void k054321_device::sound_map(address_map &map)
 	map(0x3, 0x3).r(FUNC(k054321_device::main2_r));
 }
 
-k054321_device::k054321_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
-	: device_t(mconfig, K054321, tag, owner, clock),
-	  m_left(*this, finder_base::DUMMY_TAG),
-	  m_right(*this, finder_base::DUMMY_TAG)
+k054321_device::k054321_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	device_t(mconfig, K054321, tag, owner, clock),
+	m_left(*this, finder_base::DUMMY_TAG),
+	m_right(*this, finder_base::DUMMY_TAG)
 {
 }
 
 void k054321_device::device_start()
 {
+	// make sure that device_sound_interface is configured
+	if (!m_left->inputs() && !m_right->inputs())
+		throw device_missing_dependencies();
+
+	// remember initial input gains
+	m_left_gains = std::make_unique<float[]>(m_left->inputs());
+	m_right_gains = std::make_unique<float[]>(m_right->inputs());
+
+	for (int i = 0; i < m_left->inputs(); i++)
+		m_left_gains[i] = m_left->input_gain(i);
+	for (int i = 0; i < m_right->inputs(); i++)
+		m_right_gains[i] = m_right->input_gain(i);
+
+	// register for savestates
 	save_item(NAME(m_main1));
 	save_item(NAME(m_main2));
 	save_item(NAME(m_sound1));
@@ -110,8 +124,12 @@ WRITE8_MEMBER(k054321_device::volume_reset_w)
 
 WRITE8_MEMBER(k054321_device::volume_up_w)
 {
-	m_volume ++;
-	propagate_volume();
+	// assume that max volume is 64
+	if (data && m_volume < 64)
+	{
+		m_volume++;
+		propagate_volume();
+	}
 }
 
 READ8_MEMBER(k054321_device::busy_r)
@@ -136,7 +154,7 @@ void k054321_device::propagate_volume()
 	double vol = pow(2, (m_volume - 40)/10.0);
 
 	for (int i = 0; i < m_left->inputs(); i++)
-		m_left->set_input_gain(i, m_active & 2 ? vol : 0.0);
+		m_left->set_input_gain(i, m_active & 2 ? vol * m_left_gains[i] : 0.0);
 	for (int i = 0; i < m_right->inputs(); i++)
-		m_right->set_input_gain(i, m_active & 1 ? vol : 0.0);
+		m_right->set_input_gain(i, m_active & 1 ? vol * m_right_gains[i] : 0.0);
 }
diff --git a/src/devices/machine/k054321.h b/src/devices/machine/k054321.h
index 78097b559da..2fe51758d26 100644
--- a/src/devices/machine/k054321.h
+++ b/src/devices/machine/k054321.h
@@ -29,6 +29,9 @@ private:
 	required_device<device_sound_interface> m_left;
 	required_device<device_sound_interface> m_right;
 
+	std::unique_ptr<float[]> m_left_gains;
+	std::unique_ptr<float[]> m_right_gains;
+
 	u8 m_main1;
 	u8 m_main2;
 	u8 m_sound1;
diff --git a/src/mame/drivers/rungun.cpp b/src/mame/drivers/rungun.cpp
index 0968954f148..3d88523a831 100644
--- a/src/mame/drivers/rungun.cpp
+++ b/src/mame/drivers/rungun.cpp
@@ -459,8 +459,8 @@ MACHINE_CONFIG_START(rungun_state::rng)
 	// BGM, volumes handtuned to make SFXs audible (still not 100% right tho)
 	MCFG_DEVICE_ADD("k054539_2", K054539, 18.432_MHz_XTAL)
 	MCFG_DEVICE_ADDRESS_MAP(0, k054539_map)
-	MCFG_SOUND_ROUTE(0, "rspeaker", 0.25)
-	MCFG_SOUND_ROUTE(1, "lspeaker", 0.25)
+	MCFG_SOUND_ROUTE(0, "rspeaker", 0.6)
+	MCFG_SOUND_ROUTE(1, "lspeaker", 0.6)
 MACHINE_CONFIG_END
 
 // for dual-screen output Run and Gun requires the video de-multiplexer board connected to the Jamma output, this gives you 2 Jamma connectors, one for each screen.