simple device provider added
diff --git a/providers/of/device/src/main/java/org/onlab/onos/provider/of/device/impl/OpenFlowDeviceProvider.java b/providers/of/device/src/main/java/org/onlab/onos/provider/of/device/impl/OpenFlowDeviceProvider.java
index f63b448..f7e3c95 100644
--- a/providers/of/device/src/main/java/org/onlab/onos/provider/of/device/impl/OpenFlowDeviceProvider.java
+++ b/providers/of/device/src/main/java/org/onlab/onos/provider/of/device/impl/OpenFlowDeviceProvider.java
@@ -1,22 +1,30 @@
 package org.onlab.onos.provider.of.device.impl;
 
+import static org.slf4j.LoggerFactory.getLogger;
+
+import java.net.URI;
+import java.net.URISyntaxException;
+
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.onlab.onos.net.Device;
+import org.onlab.onos.net.DeviceId;
 import org.onlab.onos.net.MastershipRole;
+import org.onlab.onos.net.device.DeviceDescription;
 import org.onlab.onos.net.device.DeviceProvider;
 import org.onlab.onos.net.device.DeviceProviderRegistry;
 import org.onlab.onos.net.device.DeviceProviderService;
 import org.onlab.onos.net.provider.AbstractProvider;
 import org.onlab.onos.net.provider.ProviderId;
+import org.onlab.onos.of.controller.Dpid;
 import org.onlab.onos.of.controller.OpenFlowController;
+import org.onlab.onos.of.controller.OpenFlowSwitchListener;
+import org.onlab.onos.of.controller.RoleState;
 import org.slf4j.Logger;
 
-import static org.slf4j.LoggerFactory.getLogger;
-
 /**
  * Provider which uses an OpenFlow controller to detect network
  * infrastructure devices.
@@ -44,6 +52,7 @@
     @Activate
     public void activate() {
         providerService = providerRegistry.register(this);
+        controller.addListener(new InternalDeviceProvider());
         log.info("Started");
     }
 
@@ -61,7 +70,55 @@
 
     @Override
     public void roleChanged(Device device, MastershipRole newRole) {
+        switch (newRole) {
+        case MASTER:
+            controller.setRole(new Dpid(device.id().uri().getSchemeSpecificPart()),
+                    RoleState.MASTER);
+            break;
+        case STANDBY:
+            controller.setRole(new Dpid(device.id().uri().getSchemeSpecificPart()),
+                    RoleState.EQUAL);
+        case NONE:
+            controller.setRole(new Dpid(device.id().uri().getSchemeSpecificPart()),
+                    RoleState.SLAVE);
+            break;
+        default:
+            log.error("Unknown Mastership state : {}", newRole);
+
+        }
         log.info("Accepting mastership role change for device {}", device.id());
     }
 
+    private class InternalDeviceProvider implements OpenFlowSwitchListener {
+
+        @Override
+        public void switchAdded(final Dpid dpid) {
+            URI uri = buildURI(dpid);
+            providerService.deviceConnected(new DeviceId(uri), new DeviceDescription() {
+
+                @Override
+                public URI deviceURI() {
+                    return buildURI(dpid);
+                }
+            });
+        }
+
+        @Override
+        public void switchRemoved(Dpid dpid) {
+            URI uri = buildURI(dpid);
+            providerService.deviceDisconnected(new DeviceId(uri));
+        }
+
+        private URI buildURI(Dpid dpid) {
+            URI uri = null;
+            try {
+                uri = new URI("of", Long.toHexString(dpid.value()), null);
+            } catch (URISyntaxException e) {
+                log.warn("URI construction for device {} failed.", dpid);
+            }
+            return uri;
+        }
+
+    }
+
 }