vgmplay: Disable POKEY and QSound devices if not required

src/devices/sound/pokey.cpp

@@ -201,8 +201,6 @@ void pokey_device::device_start()
 	//int sample_rate = clock();
 	int i;
 
-	m_clock_period = attotime::from_hz(clock());
-
 	/* Setup channels */
 	for (i=0; i<POKEY_CHANNELS; i++)
 	{
@@ -364,12 +362,15 @@ void pokey_device::device_post_load()
 
 void pokey_device::device_clock_changed()
 {
-	m_clock_period = attotime::from_hz(clock());
+	m_clock_period = clocks_to_attotime(1);
 
-	if (m_stream != nullptr)
-		m_stream->set_sample_rate(clock());
-	else
-		m_stream = stream_alloc(0, 1, clock());
+	if (clock() != 0)
+	{
+		if (m_stream != nullptr)
+			m_stream->set_sample_rate(clock());
+		else
+			m_stream = stream_alloc(0, 1, clock());
+	}
 }
 
 //-------------------------------------------------

src/emu/diexec.cpp

@@ -465,11 +465,11 @@ void device_execute_interface::interface_pre_reset()
 	// reset the total number of cycles
 	m_totalcycles = 0;
 
-	// enable all devices (except for disabled devices)
-	if (!disabled())
-		resume(SUSPEND_ANY_REASON);
-	else
+	// enable all devices (except for disabled and unclocked devices)
+	if (disabled())
 		suspend(SUSPEND_REASON_DISABLE, true);
+	else if (device().clock() != 0)
+		resume(SUSPEND_ANY_REASON);
 }
 
 

src/mame/drivers/vgmplay.cpp

@@ -1119,7 +1119,11 @@ uint8_t vgmplay_state::r8(int off) const
 
 void vgmplay_state::machine_start()
 {
-	//m_nescpu->
+	// Disable executing devices if not required
+	m_pokey[0]->set_unscaled_clock(0);
+	m_pokey[1]->set_unscaled_clock(0);
+	m_qsound->set_unscaled_clock(0);
+
 	uint32_t size = 0;
 	if(m_file->exists() && m_file->length() > 0) {
 		size = m_file->length();