Revert "Fix netplay desync when using wii-u adapter."

This reverts commit 429ae8fb01.

 Conflicts:
	Source/Core/Core/HW/SI_DeviceGCAdapter.cpp
	Source/Core/Core/HW/SI_DeviceGCAdapter.h

Source/Core/Core/HW/SI_DeviceGCAdapter.cpp

@@ -33,6 +33,86 @@ GCPadStatus CSIDevice_GCAdapter::GetPadStatus()
 	return PadStatus;
 }
 
+int CSIDevice_GCAdapter::RunBuffer(u8* _pBuffer, int _iLength)
+{
+	// For debug logging only
+	ISIDevice::RunBuffer(_pBuffer, _iLength);
+
+	// Read the command
+	EBufferCommands command = static_cast<EBufferCommands>(_pBuffer[3]);
+
+	const u8 numPAD = NetPlay_InGamePadToLocalPad(ISIDevice::m_iDeviceNumber);
+	if (numPAD < 4)
+	{
+		if (!GCAdapter::DeviceConnected(numPAD))
+		{
+			reinterpret_cast<u32*>(_pBuffer)[0] = SI_NONE;
+			return 4;
+		}
+	}
+
+	// Handle it
+	switch (command)
+	{
+	case CMD_RESET:
+	case CMD_ID:
+		*(u32*)&_pBuffer[0] = SI_GC_CONTROLLER;
+		break;
+
+	case CMD_DIRECT:
+		{
+			INFO_LOG(SERIALINTERFACE, "PAD - Direct (Length: %d)", _iLength);
+			u32 high, low;
+			GetData(high, low);
+			for (int i = 0; i < (_iLength - 1) / 2; i++)
+			{
+				_pBuffer[i + 0] = (high >> (i * 8)) & 0xff;
+				_pBuffer[i + 4] = (low >> (i * 8)) & 0xff;
+			}
+		}
+		break;
+
+	case CMD_ORIGIN:
+		{
+			INFO_LOG(SERIALINTERFACE, "PAD - Get Origin");
+
+			Calibrate();
+
+			u8* pCalibration = reinterpret_cast<u8*>(&m_Origin);
+			for (int i = 0; i < (int)sizeof(SOrigin); i++)
+			{
+				_pBuffer[i ^ 3] = *pCalibration++;
+			}
+		}
+		break;
+
+	// Recalibrate (FiRES: i am not 100 percent sure about this)
+	case CMD_RECALIBRATE:
+		{
+			INFO_LOG(SERIALINTERFACE, "PAD - Recalibrate");
+
+			Calibrate();
+
+			u8* pCalibration = reinterpret_cast<u8*>(&m_Origin);
+			for (int i = 0; i < (int)sizeof(SOrigin); i++)
+			{
+				_pBuffer[i ^ 3] = *pCalibration++;
+			}
+		}
+		break;
+
+	// DEFAULT
+	default:
+		{
+			ERROR_LOG(SERIALINTERFACE, "Unknown SI command     (0x%x)", command);
+			PanicAlert("SI: Unknown command (0x%x)", command);
+		}
+		break;
+	}
+
+	return _iLength;
+}
+
 void CSIDevice_GCController::Rumble(u8 numPad, ControlState strength)
 {
 	SIDevices device = SConfig::GetInstance().m_SIDevice[numPad];

Source/Core/Core/HW/SI_DeviceGCAdapter.h

@@ -14,4 +14,5 @@ public:
 	CSIDevice_GCAdapter(SIDevices device, int _iDeviceNumber);
 
 	GCPadStatus GetPadStatus() override;
+	int RunBuffer(u8* _pBuffer, int _iLength) override;
 };