diff -r 000000000000 -r bde4ae8d615e os/mm/mmhais/a3facl/src/shared/mlogicalsettingsobserver.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/os/mm/mmhais/a3facl/src/shared/mlogicalsettingsobserver.h	Fri Jun 15 03:10:57 2012 +0200
@@ -0,0 +1,40 @@
+/*
+* Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+*
+*/
+
+
+
+#ifndef MLOGICALSETTINGOBSERVER_H
+#define MLOGICALSETTINGOBSERVER_H
+
+#include "mlogicalchain.h"
+
+/**
+ * An interface to a set of logical audio processing unit callbacks
+ * 
+ * This serves as the method of communication between the context and the logical audio processing units.
+ *
+ * The class is a mixin and is intended to be inherited by the context class that is
+ * interested in observing the audio processing unit settings changes. 
+ * 
+ */
+ class MLogicalSettingObserver
+	{
+public:
+	virtual void ReceiveComponentSettingsChange(TUid aId, TMMRCMessageType aMessageType) = 0;
+	};
+
+#endif // MLOGICALSETTINGOBSERVER_H
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