VOL-2909 - Disaggregating rw_core/core/.

This breaks the core package into logical components. (adapter manager, adapter proxy, devices, nbi/api), as well as the "core" which aggregates all these.

Change-Id: I257ac64024a1cf3efe3f5d89d508e60e6e681fb1
diff --git a/rw_core/core/device/agent.go b/rw_core/core/device/agent.go
new file mode 100755
index 0000000..8d18e10
--- /dev/null
+++ b/rw_core/core/device/agent.go
@@ -0,0 +1,1704 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+
+ * http://www.apache.org/licenses/LICENSE-2.0
+
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package device
+
+import (
+	"context"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"github.com/golang/protobuf/ptypes"
+	"github.com/opencord/voltha-go/rw_core/core/adapter"
+	"github.com/opencord/voltha-go/rw_core/core/device/remote"
+	"github.com/opencord/voltha-lib-go/v3/pkg/kafka"
+	"reflect"
+	"sync"
+	"time"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/opencord/voltha-go/db/model"
+	coreutils "github.com/opencord/voltha-go/rw_core/utils"
+	fu "github.com/opencord/voltha-lib-go/v3/pkg/flows"
+	"github.com/opencord/voltha-lib-go/v3/pkg/log"
+	ic "github.com/opencord/voltha-protos/v3/go/inter_container"
+	ofp "github.com/opencord/voltha-protos/v3/go/openflow_13"
+	"github.com/opencord/voltha-protos/v3/go/voltha"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// Agent represents device agent attributes
+type Agent struct {
+	deviceID         string
+	parentID         string
+	deviceType       string
+	isRootdevice     bool
+	adapterProxy     *remote.AdapterProxy
+	adapterMgr       *adapter.Manager
+	deviceMgr        *Manager
+	clusterDataProxy *model.Proxy
+	exitChannel      chan int
+	device           *voltha.Device
+	requestQueue     *coreutils.RequestQueue
+	defaultTimeout   time.Duration
+	startOnce        sync.Once
+	stopOnce         sync.Once
+	stopped          bool
+}
+
+//newAgent creates a new device agent. The device will be initialized when start() is called.
+func newAgent(ap *remote.AdapterProxy, device *voltha.Device, deviceMgr *Manager, cdProxy *model.Proxy, timeout time.Duration) *Agent {
+	var agent Agent
+	agent.adapterProxy = ap
+	if device.Id == "" {
+		agent.deviceID = coreutils.CreateDeviceID()
+	} else {
+		agent.deviceID = device.Id
+	}
+
+	agent.isRootdevice = device.Root
+	agent.parentID = device.ParentId
+	agent.deviceType = device.Type
+	agent.deviceMgr = deviceMgr
+	agent.adapterMgr = deviceMgr.adapterMgr
+	agent.exitChannel = make(chan int, 1)
+	agent.clusterDataProxy = cdProxy
+	agent.defaultTimeout = timeout
+	agent.device = proto.Clone(device).(*voltha.Device)
+	agent.requestQueue = coreutils.NewRequestQueue()
+	return &agent
+}
+
+// start() saves the device to the data model and registers for callbacks on that device if deviceToCreate!=nil.
+// Otherwise, it will load the data from the dB and setup the necessary callbacks and proxies. Returns the device that
+// was started.
+func (agent *Agent) start(ctx context.Context, deviceToCreate *voltha.Device) (*voltha.Device, error) {
+	needToStart := false
+	if agent.startOnce.Do(func() { needToStart = true }); !needToStart {
+		return agent.getDevice(ctx)
+	}
+	var startSucceeded bool
+	defer func() {
+		if !startSucceeded {
+			if err := agent.stop(ctx); err != nil {
+				logger.Errorw("failed-to-cleanup-after-unsuccessful-start", log.Fields{"device-id": agent.deviceID, "error": err})
+			}
+		}
+	}()
+
+	var device *voltha.Device
+	if deviceToCreate == nil {
+		// Load the existing device
+		device := &voltha.Device{}
+		have, err := agent.clusterDataProxy.Get(ctx, "devices/"+agent.deviceID, device)
+		if err != nil {
+			return nil, err
+		} else if !have {
+			return nil, status.Errorf(codes.NotFound, "device-%s", agent.deviceID)
+		}
+
+		agent.deviceType = device.Adapter
+		agent.device = proto.Clone(device).(*voltha.Device)
+
+		logger.Infow("device-loaded-from-dB", log.Fields{"device-id": agent.deviceID})
+	} else {
+		// Create a new device
+		// Assumption is that AdminState, FlowGroups, and Flows are unitialized since this
+		// is a new device, so populate them here before passing the device to clusterDataProxy.AddWithId.
+		// agent.deviceId will also have been set during newAgent().
+		device = (proto.Clone(deviceToCreate)).(*voltha.Device)
+		device.Id = agent.deviceID
+		device.AdminState = voltha.AdminState_PREPROVISIONED
+		device.FlowGroups = &ofp.FlowGroups{Items: nil}
+		device.Flows = &ofp.Flows{Items: nil}
+		if !deviceToCreate.GetRoot() && deviceToCreate.ProxyAddress != nil {
+			// Set the default vlan ID to the one specified by the parent adapter.  It can be
+			// overwritten by the child adapter during a device update request
+			device.Vlan = deviceToCreate.ProxyAddress.ChannelId
+		}
+
+		// Add the initial device to the local model
+		if err := agent.clusterDataProxy.AddWithID(ctx, "devices", agent.deviceID, device); err != nil {
+			return nil, status.Errorf(codes.Aborted, "failed-adding-device-%s: %s", agent.deviceID, err)
+		}
+		agent.device = device
+	}
+
+	startSucceeded = true
+	logger.Debugw("device-agent-started", log.Fields{"device-id": agent.deviceID})
+
+	return agent.getDevice(ctx)
+}
+
+// stop stops the device agent.  Not much to do for now
+func (agent *Agent) stop(ctx context.Context) error {
+	needToStop := false
+	if agent.stopOnce.Do(func() { needToStop = true }); !needToStop {
+		return nil
+	}
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	logger.Infow("stopping-device-agent", log.Fields{"deviceId": agent.deviceID, "parentId": agent.parentID})
+
+	//	Remove the device from the KV store
+	if err := agent.clusterDataProxy.Remove(ctx, "devices/"+agent.deviceID); err != nil {
+		return err
+	}
+
+	close(agent.exitChannel)
+
+	agent.stopped = true
+
+	logger.Infow("device-agent-stopped", log.Fields{"device-id": agent.deviceID, "parent-id": agent.parentID})
+
+	return nil
+}
+
+// Load the most recent state from the KVStore for the device.
+func (agent *Agent) reconcileWithKVStore(ctx context.Context) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		logger.Warnw("request-aborted", log.Fields{"device-id": agent.deviceID, "error": err})
+		return
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debug("reconciling-device-agent-devicetype")
+	// TODO: context timeout
+	device := &voltha.Device{}
+	if have, err := agent.clusterDataProxy.Get(ctx, "devices/"+agent.deviceID, device); err != nil {
+		logger.Errorw("kv-get-failed", log.Fields{"device-id": agent.deviceID, "error": err})
+		return
+	} else if !have {
+		return // not found in kv
+	}
+
+	agent.deviceType = device.Adapter
+	agent.device = device
+	logger.Debugw("reconciled-device-agent-devicetype", log.Fields{"device-id": agent.deviceID, "type": agent.deviceType})
+}
+
+// onSuccess is a common callback for scenarios where we receive a nil response following a request to an adapter
+// and the only action required is to publish a successful result on kafka
+func (agent *Agent) onSuccess(rpc string, response interface{}, reqArgs ...interface{}) {
+	logger.Debugw("response successful", log.Fields{"rpc": rpc, "device-id": agent.deviceID})
+	// TODO: Post success message onto kafka
+}
+
+// onFailure is a common callback for scenarios where we receive an error response following a request to an adapter
+// and the only action required is to publish the failed result on kafka
+func (agent *Agent) onFailure(rpc string, response interface{}, reqArgs ...interface{}) {
+	if res, ok := response.(error); ok {
+		logger.Errorw("rpc-failed", log.Fields{"rpc": rpc, "device-id": agent.deviceID, "error": res, "args": reqArgs})
+	} else {
+		logger.Errorw("rpc-failed-invalid-error", log.Fields{"rpc": rpc, "device-id": agent.deviceID, "args": reqArgs})
+	}
+	// TODO: Post failure message onto kafka
+}
+
+func (agent *Agent) waitForAdapterResponse(ctx context.Context, cancel context.CancelFunc, rpc string, ch chan *kafka.RpcResponse,
+	onSuccess coreutils.ResponseCallback, onFailure coreutils.ResponseCallback, reqArgs ...interface{}) {
+	defer cancel()
+	select {
+	case rpcResponse, ok := <-ch:
+		if !ok {
+			onFailure(rpc, status.Errorf(codes.Aborted, "channel-closed"), reqArgs)
+		} else if rpcResponse.Err != nil {
+			onFailure(rpc, rpcResponse.Err, reqArgs)
+		} else {
+			onSuccess(rpc, rpcResponse.Reply, reqArgs)
+		}
+	case <-ctx.Done():
+		onFailure(rpc, ctx.Err(), reqArgs)
+	}
+}
+
+// getDevice returns the device data from cache
+func (agent *Agent) getDevice(ctx context.Context) (*voltha.Device, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+	return proto.Clone(agent.device).(*voltha.Device), nil
+}
+
+// getDeviceWithoutLock is a helper function to be used ONLY by any device agent function AFTER it has acquired the device lock.
+func (agent *Agent) getDeviceWithoutLock() *voltha.Device {
+	return proto.Clone(agent.device).(*voltha.Device)
+}
+
+// enableDevice activates a preprovisioned or a disable device
+func (agent *Agent) enableDevice(ctx context.Context) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	logger.Debugw("enableDevice", log.Fields{"device-id": agent.deviceID})
+
+	cloned := agent.getDeviceWithoutLock()
+
+	// First figure out which adapter will handle this device type.  We do it at this stage as allow devices to be
+	// pre-provisioned with the required adapter not registered.   At this stage, since we need to communicate
+	// with the adapter then we need to know the adapter that will handle this request
+	adapterName, err := agent.adapterMgr.GetAdapterType(cloned.Type)
+	if err != nil {
+		return err
+	}
+	cloned.Adapter = adapterName
+
+	if cloned.AdminState == voltha.AdminState_ENABLED {
+		logger.Warnw("device-already-enabled", log.Fields{"device-id": agent.deviceID})
+		err = status.Error(codes.FailedPrecondition, fmt.Sprintf("cannot-enable-an-already-enabled-device: %s ", cloned.Id))
+		return err
+	}
+
+	if cloned.AdminState == voltha.AdminState_DELETED {
+		// This is a temporary state when a device is deleted before it gets removed from the model.
+		err = status.Error(codes.FailedPrecondition, fmt.Sprintf("cannot-enable-a-deleted-device: %s ", cloned.Id))
+		return err
+	}
+
+	previousAdminState := cloned.AdminState
+
+	// Update the Admin State and set the operational state to activating before sending the request to the
+	// Adapters
+	if err := agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, voltha.AdminState_ENABLED, cloned.ConnectStatus, voltha.OperStatus_ACTIVATING); err != nil {
+		return err
+	}
+
+	// Adopt the device if it was in pre-provision state.  In all other cases, try to re-enable it.
+	device := proto.Clone(cloned).(*voltha.Device)
+	var ch chan *kafka.RpcResponse
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	if previousAdminState == voltha.AdminState_PREPROVISIONED {
+		ch, err = agent.adapterProxy.AdoptDevice(subCtx, device)
+	} else {
+		ch, err = agent.adapterProxy.ReEnableDevice(subCtx, device)
+	}
+	if err != nil {
+		cancel()
+		return err
+	}
+	// Wait for response
+	go agent.waitForAdapterResponse(subCtx, cancel, "enableDevice", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) waitForAdapterFlowResponse(ctx context.Context, cancel context.CancelFunc, ch chan *kafka.RpcResponse, response coreutils.Response) {
+	defer cancel()
+	select {
+	case rpcResponse, ok := <-ch:
+		if !ok {
+			response.Error(status.Errorf(codes.Aborted, "channel-closed"))
+		} else if rpcResponse.Err != nil {
+			response.Error(rpcResponse.Err)
+		} else {
+			response.Done()
+		}
+	case <-ctx.Done():
+		response.Error(ctx.Err())
+	}
+}
+
+//deleteFlowWithoutPreservingOrder removes a flow specified by index from the flows slice.  This function will
+//panic if the index is out of range.
+func deleteFlowWithoutPreservingOrder(flows []*ofp.OfpFlowStats, index int) []*ofp.OfpFlowStats {
+	flows[index] = flows[len(flows)-1]
+	flows[len(flows)-1] = nil
+	return flows[:len(flows)-1]
+}
+
+//deleteGroupWithoutPreservingOrder removes a group specified by index from the groups slice.  This function will
+//panic if the index is out of range.
+func deleteGroupWithoutPreservingOrder(groups []*ofp.OfpGroupEntry, index int) []*ofp.OfpGroupEntry {
+	groups[index] = groups[len(groups)-1]
+	groups[len(groups)-1] = nil
+	return groups[:len(groups)-1]
+}
+
+func flowsToUpdateToDelete(newFlows, existingFlows []*ofp.OfpFlowStats) (updatedNewFlows, flowsToDelete, updatedAllFlows []*ofp.OfpFlowStats) {
+	// Process flows
+	for _, flow := range existingFlows {
+		if idx := fu.FindFlows(newFlows, flow); idx == -1 {
+			updatedAllFlows = append(updatedAllFlows, flow)
+		} else {
+			// We have a matching flow (i.e. the following field matches: "TableId", "Priority", "Flags", "Cookie",
+			// "Match".  If this is an exact match (i.e. all other fields matches as well) then this flow will be
+			// ignored.  Otherwise, the previous flow will be deleted and the new one added
+			if proto.Equal(newFlows[idx], flow) {
+				// Flow already exist, remove it from the new flows but keep it in the updated flows slice
+				newFlows = deleteFlowWithoutPreservingOrder(newFlows, idx)
+				updatedAllFlows = append(updatedAllFlows, flow)
+			} else {
+				// Minor change to flow, delete old and add new one
+				flowsToDelete = append(flowsToDelete, flow)
+			}
+		}
+	}
+	updatedAllFlows = append(updatedAllFlows, newFlows...)
+	return newFlows, flowsToDelete, updatedAllFlows
+}
+
+func groupsToUpdateToDelete(newGroups, existingGroups []*ofp.OfpGroupEntry) (updatedNewGroups, groupsToDelete, updatedAllGroups []*ofp.OfpGroupEntry) {
+	for _, group := range existingGroups {
+		if idx := fu.FindGroup(newGroups, group.Desc.GroupId); idx == -1 { // does not exist now
+			updatedAllGroups = append(updatedAllGroups, group)
+		} else {
+			// Follow same logic as flows
+			if proto.Equal(newGroups[idx], group) {
+				// Group already exist, remove it from the new groups
+				newGroups = deleteGroupWithoutPreservingOrder(newGroups, idx)
+				updatedAllGroups = append(updatedAllGroups, group)
+			} else {
+				// Minor change to group, delete old and add new one
+				groupsToDelete = append(groupsToDelete, group)
+			}
+		}
+	}
+	updatedAllGroups = append(updatedAllGroups, newGroups...)
+	return newGroups, groupsToDelete, updatedAllGroups
+}
+
+func (agent *Agent) addFlowsAndGroupsToAdapter(ctx context.Context, newFlows []*ofp.OfpFlowStats, newGroups []*ofp.OfpGroupEntry, flowMetadata *voltha.FlowMetadata) (coreutils.Response, error) {
+	logger.Debugw("add-flows-groups-to-adapters", log.Fields{"device-id": agent.deviceID, "flows": newFlows, "groups": newGroups, "flow-metadata": flowMetadata})
+
+	if (len(newFlows) | len(newGroups)) == 0 {
+		logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": newFlows, "groups": newGroups})
+		return coreutils.DoneResponse(), nil
+	}
+
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return coreutils.DoneResponse(), err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	device := agent.getDeviceWithoutLock()
+	dType := agent.adapterMgr.GetDeviceType(device.Type)
+	if dType == nil {
+		return coreutils.DoneResponse(), status.Errorf(codes.FailedPrecondition, "non-existent-device-type-%s", device.Type)
+	}
+
+	existingFlows := proto.Clone(device.Flows).(*voltha.Flows)
+	existingGroups := proto.Clone(device.FlowGroups).(*ofp.FlowGroups)
+
+	// Process flows
+	newFlows, flowsToDelete, updatedAllFlows := flowsToUpdateToDelete(newFlows, existingFlows.Items)
+
+	// Process groups
+	newGroups, groupsToDelete, updatedAllGroups := groupsToUpdateToDelete(newGroups, existingGroups.Items)
+
+	// Sanity check
+	if (len(updatedAllFlows) | len(flowsToDelete) | len(updatedAllGroups) | len(groupsToDelete)) == 0 {
+		logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": newFlows, "groups": newGroups})
+		return coreutils.DoneResponse(), nil
+	}
+
+	// store the changed data
+	device.Flows = &voltha.Flows{Items: updatedAllFlows}
+	device.FlowGroups = &voltha.FlowGroups{Items: updatedAllGroups}
+	if err := agent.updateDeviceWithoutLock(ctx, device); err != nil {
+		return coreutils.DoneResponse(), status.Errorf(codes.Internal, "failure-updating-device-%s", agent.deviceID)
+	}
+
+	// Send update to adapters
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	response := coreutils.NewResponse()
+	if !dType.AcceptsAddRemoveFlowUpdates {
+		if len(updatedAllGroups) != 0 && reflect.DeepEqual(existingGroups.Items, updatedAllGroups) && len(updatedAllFlows) != 0 && reflect.DeepEqual(existingFlows.Items, updatedAllFlows) {
+			logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": newFlows, "groups": newGroups})
+			cancel()
+			return coreutils.DoneResponse(), nil
+		}
+		rpcResponse, err := agent.adapterProxy.UpdateFlowsBulk(subCtx, device, &voltha.Flows{Items: updatedAllFlows}, &voltha.FlowGroups{Items: updatedAllGroups}, flowMetadata)
+		if err != nil {
+			cancel()
+			return coreutils.DoneResponse(), err
+		}
+		go agent.waitForAdapterFlowResponse(subCtx, cancel, rpcResponse, response)
+	} else {
+		flowChanges := &ofp.FlowChanges{
+			ToAdd:    &voltha.Flows{Items: newFlows},
+			ToRemove: &voltha.Flows{Items: flowsToDelete},
+		}
+		groupChanges := &ofp.FlowGroupChanges{
+			ToAdd:    &voltha.FlowGroups{Items: newGroups},
+			ToRemove: &voltha.FlowGroups{Items: groupsToDelete},
+			ToUpdate: &voltha.FlowGroups{Items: []*ofp.OfpGroupEntry{}},
+		}
+		rpcResponse, err := agent.adapterProxy.UpdateFlowsIncremental(subCtx, device, flowChanges, groupChanges, flowMetadata)
+		if err != nil {
+			cancel()
+			return coreutils.DoneResponse(), err
+		}
+		go agent.waitForAdapterFlowResponse(subCtx, cancel, rpcResponse, response)
+	}
+	return response, nil
+}
+
+//addFlowsAndGroups adds the "newFlows" and "newGroups" from the existing flows/groups and sends the update to the
+//adapters
+func (agent *Agent) addFlowsAndGroups(ctx context.Context, newFlows []*ofp.OfpFlowStats, newGroups []*ofp.OfpGroupEntry, flowMetadata *voltha.FlowMetadata) error {
+	response, err := agent.addFlowsAndGroupsToAdapter(ctx, newFlows, newGroups, flowMetadata)
+	if err != nil {
+		return err
+	}
+	if errs := coreutils.WaitForNilOrErrorResponses(agent.defaultTimeout, response); errs != nil {
+		logger.Warnw("no-adapter-response", log.Fields{"device-id": agent.deviceID, "result": errs})
+		return status.Errorf(codes.Aborted, "flow-failure-device-%s", agent.deviceID)
+	}
+	return nil
+}
+
+func (agent *Agent) deleteFlowsAndGroupsFromAdapter(ctx context.Context, flowsToDel []*ofp.OfpFlowStats, groupsToDel []*ofp.OfpGroupEntry, flowMetadata *voltha.FlowMetadata) (coreutils.Response, error) {
+	logger.Debugw("delete-flows-groups-from-adapter", log.Fields{"device-id": agent.deviceID, "flows": flowsToDel, "groups": groupsToDel})
+
+	if (len(flowsToDel) | len(groupsToDel)) == 0 {
+		logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": flowsToDel, "groups": groupsToDel})
+		return coreutils.DoneResponse(), nil
+	}
+
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return coreutils.DoneResponse(), err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	device := agent.getDeviceWithoutLock()
+	dType := agent.adapterMgr.GetDeviceType(device.Type)
+	if dType == nil {
+		return coreutils.DoneResponse(), status.Errorf(codes.FailedPrecondition, "non-existent-device-type-%s", device.Type)
+	}
+
+	existingFlows := proto.Clone(device.Flows).(*voltha.Flows)
+	existingGroups := proto.Clone(device.FlowGroups).(*ofp.FlowGroups)
+
+	var flowsToKeep []*ofp.OfpFlowStats
+	var groupsToKeep []*ofp.OfpGroupEntry
+
+	// Process flows
+	for _, flow := range existingFlows.Items {
+		if idx := fu.FindFlows(flowsToDel, flow); idx == -1 {
+			flowsToKeep = append(flowsToKeep, flow)
+		}
+	}
+
+	// Process groups
+	for _, group := range existingGroups.Items {
+		if fu.FindGroup(groupsToDel, group.Desc.GroupId) == -1 { // does not exist now
+			groupsToKeep = append(groupsToKeep, group)
+		}
+	}
+
+	logger.Debugw("deleteFlowsAndGroups",
+		log.Fields{
+			"device-id":      agent.deviceID,
+			"flows-to-del":   len(flowsToDel),
+			"flows-to-keep":  len(flowsToKeep),
+			"groups-to-del":  len(groupsToDel),
+			"groups-to-keep": len(groupsToKeep),
+		})
+
+	// Sanity check
+	if (len(flowsToKeep) | len(flowsToDel) | len(groupsToKeep) | len(groupsToDel)) == 0 {
+		logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows-to-del": flowsToDel, "groups-to-del": groupsToDel})
+		return coreutils.DoneResponse(), nil
+	}
+
+	// store the changed data
+	device.Flows = &voltha.Flows{Items: flowsToKeep}
+	device.FlowGroups = &voltha.FlowGroups{Items: groupsToKeep}
+	if err := agent.updateDeviceWithoutLock(ctx, device); err != nil {
+		return coreutils.DoneResponse(), status.Errorf(codes.Internal, "failure-updating-%s", agent.deviceID)
+	}
+
+	// Send update to adapters
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	response := coreutils.NewResponse()
+	if !dType.AcceptsAddRemoveFlowUpdates {
+		if len(groupsToKeep) != 0 && reflect.DeepEqual(existingGroups.Items, groupsToKeep) && len(flowsToKeep) != 0 && reflect.DeepEqual(existingFlows.Items, flowsToKeep) {
+			logger.Debugw("nothing-to-update", log.Fields{"deviceId": agent.deviceID, "flowsToDel": flowsToDel, "groupsToDel": groupsToDel})
+			cancel()
+			return coreutils.DoneResponse(), nil
+		}
+		rpcResponse, err := agent.adapterProxy.UpdateFlowsBulk(subCtx, device, &voltha.Flows{Items: flowsToKeep}, &voltha.FlowGroups{Items: groupsToKeep}, flowMetadata)
+		if err != nil {
+			cancel()
+			return coreutils.DoneResponse(), err
+		}
+		go agent.waitForAdapterFlowResponse(subCtx, cancel, rpcResponse, response)
+	} else {
+		flowChanges := &ofp.FlowChanges{
+			ToAdd:    &voltha.Flows{Items: []*ofp.OfpFlowStats{}},
+			ToRemove: &voltha.Flows{Items: flowsToDel},
+		}
+		groupChanges := &ofp.FlowGroupChanges{
+			ToAdd:    &voltha.FlowGroups{Items: []*ofp.OfpGroupEntry{}},
+			ToRemove: &voltha.FlowGroups{Items: groupsToDel},
+			ToUpdate: &voltha.FlowGroups{Items: []*ofp.OfpGroupEntry{}},
+		}
+		rpcResponse, err := agent.adapterProxy.UpdateFlowsIncremental(subCtx, device, flowChanges, groupChanges, flowMetadata)
+		if err != nil {
+			cancel()
+			return coreutils.DoneResponse(), err
+		}
+		go agent.waitForAdapterFlowResponse(subCtx, cancel, rpcResponse, response)
+	}
+	return response, nil
+}
+
+//deleteFlowsAndGroups removes the "flowsToDel" and "groupsToDel" from the existing flows/groups and sends the update to the
+//adapters
+func (agent *Agent) deleteFlowsAndGroups(ctx context.Context, flowsToDel []*ofp.OfpFlowStats, groupsToDel []*ofp.OfpGroupEntry, flowMetadata *voltha.FlowMetadata) error {
+	response, err := agent.deleteFlowsAndGroupsFromAdapter(ctx, flowsToDel, groupsToDel, flowMetadata)
+	if err != nil {
+		return err
+	}
+	if res := coreutils.WaitForNilOrErrorResponses(agent.defaultTimeout, response); res != nil {
+		return status.Errorf(codes.Aborted, "errors-%s", res)
+	}
+	return nil
+}
+
+func (agent *Agent) updateFlowsAndGroupsToAdapter(ctx context.Context, updatedFlows []*ofp.OfpFlowStats, updatedGroups []*ofp.OfpGroupEntry, flowMetadata *voltha.FlowMetadata) (coreutils.Response, error) {
+	logger.Debugw("updateFlowsAndGroups", log.Fields{"device-id": agent.deviceID, "flows": updatedFlows, "groups": updatedGroups})
+
+	if (len(updatedFlows) | len(updatedGroups)) == 0 {
+		logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": updatedFlows, "groups": updatedGroups})
+		return coreutils.DoneResponse(), nil
+	}
+
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return coreutils.DoneResponse(), err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	device := agent.getDeviceWithoutLock()
+	if device.OperStatus != voltha.OperStatus_ACTIVE || device.ConnectStatus != voltha.ConnectStatus_REACHABLE || device.AdminState != voltha.AdminState_ENABLED {
+		return coreutils.DoneResponse(), status.Errorf(codes.FailedPrecondition, "invalid device states")
+	}
+	dType := agent.adapterMgr.GetDeviceType(device.Type)
+	if dType == nil {
+		return coreutils.DoneResponse(), status.Errorf(codes.FailedPrecondition, "non-existent-device-type-%s", device.Type)
+	}
+
+	existingFlows := proto.Clone(device.Flows).(*voltha.Flows)
+	existingGroups := proto.Clone(device.FlowGroups).(*ofp.FlowGroups)
+
+	if len(updatedGroups) != 0 && reflect.DeepEqual(existingGroups.Items, updatedGroups) && len(updatedFlows) != 0 && reflect.DeepEqual(existingFlows.Items, updatedFlows) {
+		logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": updatedFlows, "groups": updatedGroups})
+		return coreutils.DoneResponse(), nil
+	}
+
+	logger.Debugw("updating-flows-and-groups",
+		log.Fields{
+			"device-id":      agent.deviceID,
+			"updated-flows":  updatedFlows,
+			"updated-groups": updatedGroups,
+		})
+
+	// store the updated data
+	device.Flows = &voltha.Flows{Items: updatedFlows}
+	device.FlowGroups = &voltha.FlowGroups{Items: updatedGroups}
+	if err := agent.updateDeviceWithoutLock(ctx, device); err != nil {
+		return coreutils.DoneResponse(), status.Errorf(codes.Internal, "failure-updating-%s", agent.deviceID)
+	}
+
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	response := coreutils.NewResponse()
+	// Process bulk flow update differently than incremental update
+	if !dType.AcceptsAddRemoveFlowUpdates {
+		rpcResponse, err := agent.adapterProxy.UpdateFlowsBulk(subCtx, device, &voltha.Flows{Items: updatedFlows}, &voltha.FlowGroups{Items: updatedGroups}, nil)
+		if err != nil {
+			cancel()
+			return coreutils.DoneResponse(), err
+		}
+		go agent.waitForAdapterFlowResponse(subCtx, cancel, rpcResponse, response)
+	} else {
+		var flowsToAdd []*ofp.OfpFlowStats
+		var flowsToDelete []*ofp.OfpFlowStats
+		var groupsToAdd []*ofp.OfpGroupEntry
+		var groupsToDelete []*ofp.OfpGroupEntry
+
+		// Process flows
+		for _, flow := range updatedFlows {
+			if idx := fu.FindFlows(existingFlows.Items, flow); idx == -1 {
+				flowsToAdd = append(flowsToAdd, flow)
+			}
+		}
+		for _, flow := range existingFlows.Items {
+			if idx := fu.FindFlows(updatedFlows, flow); idx != -1 {
+				flowsToDelete = append(flowsToDelete, flow)
+			}
+		}
+
+		// Process groups
+		for _, g := range updatedGroups {
+			if fu.FindGroup(existingGroups.Items, g.Desc.GroupId) == -1 { // does not exist now
+				groupsToAdd = append(groupsToAdd, g)
+			}
+		}
+		for _, group := range existingGroups.Items {
+			if fu.FindGroup(updatedGroups, group.Desc.GroupId) != -1 { // does not exist now
+				groupsToDelete = append(groupsToDelete, group)
+			}
+		}
+
+		logger.Debugw("updating-flows-and-groups",
+			log.Fields{
+				"device-id":        agent.deviceID,
+				"flows-to-add":     flowsToAdd,
+				"flows-to-delete":  flowsToDelete,
+				"groups-to-add":    groupsToAdd,
+				"groups-to-delete": groupsToDelete,
+			})
+
+		// Sanity check
+		if (len(flowsToAdd) | len(flowsToDelete) | len(groupsToAdd) | len(groupsToDelete) | len(updatedGroups)) == 0 {
+			logger.Debugw("nothing-to-update", log.Fields{"device-id": agent.deviceID, "flows": updatedFlows, "groups": updatedGroups})
+			cancel()
+			return coreutils.DoneResponse(), nil
+		}
+
+		flowChanges := &ofp.FlowChanges{
+			ToAdd:    &voltha.Flows{Items: flowsToAdd},
+			ToRemove: &voltha.Flows{Items: flowsToDelete},
+		}
+		groupChanges := &ofp.FlowGroupChanges{
+			ToAdd:    &voltha.FlowGroups{Items: groupsToAdd},
+			ToRemove: &voltha.FlowGroups{Items: groupsToDelete},
+			ToUpdate: &voltha.FlowGroups{Items: updatedGroups},
+		}
+		rpcResponse, err := agent.adapterProxy.UpdateFlowsIncremental(subCtx, device, flowChanges, groupChanges, flowMetadata)
+		if err != nil {
+			cancel()
+			return coreutils.DoneResponse(), err
+		}
+		go agent.waitForAdapterFlowResponse(subCtx, cancel, rpcResponse, response)
+	}
+
+	return response, nil
+}
+
+//updateFlowsAndGroups replaces the existing flows and groups with "updatedFlows" and "updatedGroups" respectively. It
+//also sends the updates to the adapters
+func (agent *Agent) updateFlowsAndGroups(ctx context.Context, updatedFlows []*ofp.OfpFlowStats, updatedGroups []*ofp.OfpGroupEntry, flowMetadata *voltha.FlowMetadata) error {
+	response, err := agent.updateFlowsAndGroupsToAdapter(ctx, updatedFlows, updatedGroups, flowMetadata)
+	if err != nil {
+		return err
+	}
+	if res := coreutils.WaitForNilOrErrorResponses(agent.defaultTimeout, response); res != nil {
+		return status.Errorf(codes.Aborted, "errors-%s", res)
+	}
+	return nil
+}
+
+//deleteAllFlows deletes all flows in the device table
+func (agent *Agent) deleteAllFlows(ctx context.Context) error {
+	logger.Debugw("deleteAllFlows", log.Fields{"deviceId": agent.deviceID})
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	device := agent.getDeviceWithoutLock()
+	// purge all flows on the device by setting it to nil
+	device.Flows = &ofp.Flows{Items: nil}
+	if err := agent.updateDeviceWithoutLock(ctx, device); err != nil {
+		// The caller logs the error
+		return err
+	}
+	return nil
+}
+
+//disableDevice disable a device
+func (agent *Agent) disableDevice(ctx context.Context) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("disableDevice", log.Fields{"device-id": agent.deviceID})
+
+	cloned := agent.getDeviceWithoutLock()
+
+	if cloned.AdminState == voltha.AdminState_DISABLED {
+		logger.Debugw("device-already-disabled", log.Fields{"id": agent.deviceID})
+		return nil
+	}
+	if cloned.AdminState == voltha.AdminState_PREPROVISIONED ||
+		cloned.AdminState == voltha.AdminState_DELETED {
+		return status.Errorf(codes.FailedPrecondition, "deviceId:%s, invalid-admin-state:%s", agent.deviceID, cloned.AdminState)
+	}
+
+	// Update the Admin State and operational state before sending the request out
+	if err := agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, voltha.AdminState_DISABLED, cloned.ConnectStatus, voltha.OperStatus_UNKNOWN); err != nil {
+		return err
+	}
+
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.DisableDevice(subCtx, proto.Clone(cloned).(*voltha.Device))
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "disableDevice", ch, agent.onSuccess, agent.onFailure)
+
+	return nil
+}
+
+func (agent *Agent) rebootDevice(ctx context.Context) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("rebootDevice", log.Fields{"device-id": agent.deviceID})
+
+	device := agent.getDeviceWithoutLock()
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.RebootDevice(subCtx, device)
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "rebootDevice", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) deleteDevice(ctx context.Context) error {
+	logger.Debugw("deleteDevice", log.Fields{"device-id": agent.deviceID})
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	cloned := agent.getDeviceWithoutLock()
+
+	previousState := cloned.AdminState
+
+	// No check is required when deleting a device.  Changing the state to DELETE will trigger the removal of this
+	// device by the state machine
+	if err := agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, voltha.AdminState_DELETED, cloned.ConnectStatus, cloned.OperStatus); err != nil {
+		return err
+	}
+
+	// If the device was in pre-prov state (only parent device are in that state) then do not send the request to the
+	// adapter
+	if previousState != ic.AdminState_PREPROVISIONED {
+		subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+		ch, err := agent.adapterProxy.DeleteDevice(subCtx, cloned)
+		if err != nil {
+			cancel()
+			return err
+		}
+		go agent.waitForAdapterResponse(subCtx, cancel, "deleteDevice", ch, agent.onSuccess, agent.onFailure)
+	}
+	return nil
+}
+
+func (agent *Agent) setParentID(ctx context.Context, device *voltha.Device, parentID string) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	logger.Debugw("setParentId", log.Fields{"device-id": device.Id, "parent-id": parentID})
+
+	cloned := agent.getDeviceWithoutLock()
+	cloned.ParentId = parentID
+	// Store the device
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, ""); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (agent *Agent) updatePmConfigs(ctx context.Context, pmConfigs *voltha.PmConfigs) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("updatePmConfigs", log.Fields{"device-id": pmConfigs.Id})
+
+	cloned := agent.getDeviceWithoutLock()
+	cloned.PmConfigs = proto.Clone(pmConfigs).(*voltha.PmConfigs)
+	// Store the device
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, ""); err != nil {
+		return err
+	}
+	// Send the request to the adapter
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.UpdatePmConfigs(subCtx, cloned, pmConfigs)
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "updatePmConfigs", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) initPmConfigs(ctx context.Context, pmConfigs *voltha.PmConfigs) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("initPmConfigs", log.Fields{"device-id": pmConfigs.Id})
+
+	cloned := agent.getDeviceWithoutLock()
+	cloned.PmConfigs = proto.Clone(pmConfigs).(*voltha.PmConfigs)
+	updateCtx := context.WithValue(ctx, model.RequestTimestamp, time.Now().UnixNano())
+	return agent.updateDeviceInStoreWithoutLock(updateCtx, cloned, false, "")
+}
+
+func (agent *Agent) listPmConfigs(ctx context.Context) (*voltha.PmConfigs, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("listPmConfigs", log.Fields{"device-id": agent.deviceID})
+
+	return agent.getDeviceWithoutLock().PmConfigs, nil
+}
+
+func (agent *Agent) downloadImage(ctx context.Context, img *voltha.ImageDownload) (*voltha.OperationResp, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	logger.Debugw("downloadImage", log.Fields{"device-id": agent.deviceID})
+
+	device := agent.getDeviceWithoutLock()
+
+	if device.AdminState != voltha.AdminState_ENABLED {
+		return nil, status.Errorf(codes.FailedPrecondition, "device-id:%s, expected-admin-state:%s", agent.deviceID, voltha.AdminState_ENABLED)
+	}
+	// Save the image
+	clonedImg := proto.Clone(img).(*voltha.ImageDownload)
+	clonedImg.DownloadState = voltha.ImageDownload_DOWNLOAD_REQUESTED
+	cloned := proto.Clone(device).(*voltha.Device)
+	if cloned.ImageDownloads == nil {
+		cloned.ImageDownloads = []*voltha.ImageDownload{clonedImg}
+	} else {
+		if device.AdminState != voltha.AdminState_ENABLED {
+			logger.Debugw("device-not-enabled", log.Fields{"id": agent.deviceID})
+			return nil, status.Errorf(codes.FailedPrecondition, "deviceId:%s, expected-admin-state:%s", agent.deviceID, voltha.AdminState_ENABLED)
+		}
+		// Save the image
+		clonedImg := proto.Clone(img).(*voltha.ImageDownload)
+		clonedImg.DownloadState = voltha.ImageDownload_DOWNLOAD_REQUESTED
+		if device.ImageDownloads == nil {
+			device.ImageDownloads = []*voltha.ImageDownload{clonedImg}
+		} else {
+			device.ImageDownloads = append(device.ImageDownloads, clonedImg)
+		}
+		if err := agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, voltha.AdminState_DOWNLOADING_IMAGE, device.ConnectStatus, device.OperStatus); err != nil {
+			return nil, err
+		}
+
+		// Send the request to the adapter
+		subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+		ch, err := agent.adapterProxy.DownloadImage(ctx, cloned, clonedImg)
+		if err != nil {
+			cancel()
+			return nil, err
+		}
+		go agent.waitForAdapterResponse(subCtx, cancel, "downloadImage", ch, agent.onSuccess, agent.onFailure)
+	}
+	return &voltha.OperationResp{Code: voltha.OperationResp_OPERATION_SUCCESS}, nil
+}
+
+// isImageRegistered is a helper method to figure out if an image is already registered
+func isImageRegistered(img *voltha.ImageDownload, device *voltha.Device) bool {
+	for _, image := range device.ImageDownloads {
+		if image.Id == img.Id && image.Name == img.Name {
+			return true
+		}
+	}
+	return false
+}
+
+func (agent *Agent) cancelImageDownload(ctx context.Context, img *voltha.ImageDownload) (*voltha.OperationResp, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	logger.Debugw("cancelImageDownload", log.Fields{"device-id": agent.deviceID})
+
+	device := agent.getDeviceWithoutLock()
+
+	// Verify whether the Image is in the list of image being downloaded
+	if !isImageRegistered(img, device) {
+		return nil, status.Errorf(codes.FailedPrecondition, "device-id:%s, image-not-registered:%s", agent.deviceID, img.Name)
+	}
+
+	// Update image download state
+	for _, image := range device.ImageDownloads {
+		if image.Id == img.Id && image.Name == img.Name {
+			image.DownloadState = voltha.ImageDownload_DOWNLOAD_CANCELLED
+		}
+	}
+
+	if device.AdminState == voltha.AdminState_DOWNLOADING_IMAGE {
+		// Set the device to Enabled
+		if err := agent.updateDeviceStateInStoreWithoutLock(ctx, device, voltha.AdminState_ENABLED, device.ConnectStatus, device.OperStatus); err != nil {
+			return nil, err
+		}
+		subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+		ch, err := agent.adapterProxy.CancelImageDownload(subCtx, device, img)
+		if err != nil {
+			cancel()
+			return nil, err
+		}
+		go agent.waitForAdapterResponse(subCtx, cancel, "cancelImageDownload", ch, agent.onSuccess, agent.onFailure)
+	}
+	return &voltha.OperationResp{Code: voltha.OperationResp_OPERATION_SUCCESS}, nil
+}
+
+func (agent *Agent) activateImage(ctx context.Context, img *voltha.ImageDownload) (*voltha.OperationResp, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("activateImage", log.Fields{"device-id": agent.deviceID})
+	cloned := agent.getDeviceWithoutLock()
+
+	// Verify whether the Image is in the list of image being downloaded
+	if !isImageRegistered(img, cloned) {
+		return nil, status.Errorf(codes.FailedPrecondition, "device-id:%s, image-not-registered:%s", agent.deviceID, img.Name)
+	}
+
+	if cloned.AdminState == voltha.AdminState_DOWNLOADING_IMAGE {
+		return nil, status.Errorf(codes.FailedPrecondition, "device-id:%s, device-in-downloading-state:%s", agent.deviceID, img.Name)
+	}
+	// Update image download state
+	for _, image := range cloned.ImageDownloads {
+		if image.Id == img.Id && image.Name == img.Name {
+			image.ImageState = voltha.ImageDownload_IMAGE_ACTIVATING
+		}
+	}
+	// Set the device to downloading_image
+	if err := agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, voltha.AdminState_DOWNLOADING_IMAGE, cloned.ConnectStatus, cloned.OperStatus); err != nil {
+		return nil, err
+	}
+
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.ActivateImageUpdate(subCtx, proto.Clone(cloned).(*voltha.Device), img)
+	if err != nil {
+		cancel()
+		return nil, err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "activateImageUpdate", ch, agent.onSuccess, agent.onFailure)
+
+	// The status of the AdminState will be changed following the update_download_status response from the adapter
+	// The image name will also be removed from the device list
+	return &voltha.OperationResp{Code: voltha.OperationResp_OPERATION_SUCCESS}, nil
+}
+
+func (agent *Agent) revertImage(ctx context.Context, img *voltha.ImageDownload) (*voltha.OperationResp, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("revertImage", log.Fields{"device-id": agent.deviceID})
+
+	cloned := agent.getDeviceWithoutLock()
+
+	// Verify whether the Image is in the list of image being downloaded
+	if !isImageRegistered(img, cloned) {
+		return nil, status.Errorf(codes.FailedPrecondition, "deviceId:%s, image-not-registered:%s", agent.deviceID, img.Name)
+	}
+
+	if cloned.AdminState != voltha.AdminState_ENABLED {
+		return nil, status.Errorf(codes.FailedPrecondition, "deviceId:%s, device-not-enabled-state:%s", agent.deviceID, img.Name)
+	}
+	// Update image download state
+	for _, image := range cloned.ImageDownloads {
+		if image.Id == img.Id && image.Name == img.Name {
+			image.ImageState = voltha.ImageDownload_IMAGE_REVERTING
+		}
+	}
+
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, ""); err != nil {
+		return nil, err
+	}
+
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.RevertImageUpdate(subCtx, proto.Clone(cloned).(*voltha.Device), img)
+	if err != nil {
+		cancel()
+		return nil, err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "revertImageUpdate", ch, agent.onSuccess, agent.onFailure)
+
+	return &voltha.OperationResp{Code: voltha.OperationResp_OPERATION_SUCCESS}, nil
+}
+
+func (agent *Agent) getImageDownloadStatus(ctx context.Context, img *voltha.ImageDownload) (*voltha.ImageDownload, error) {
+	logger.Debugw("getImageDownloadStatus", log.Fields{"device-id": agent.deviceID})
+
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	device := agent.getDeviceWithoutLock()
+	ch, err := agent.adapterProxy.GetImageDownloadStatus(ctx, device, img)
+	agent.requestQueue.RequestComplete()
+	if err != nil {
+		return nil, err
+	}
+	// Wait for the adapter response
+	rpcResponse, ok := <-ch
+	if !ok {
+		return nil, status.Errorf(codes.Aborted, "channel-closed-device-id-%s", agent.deviceID)
+	}
+	if rpcResponse.Err != nil {
+		return nil, rpcResponse.Err
+	}
+	// Successful response
+	imgDownload := &voltha.ImageDownload{}
+	if err := ptypes.UnmarshalAny(rpcResponse.Reply, imgDownload); err != nil {
+		return nil, status.Errorf(codes.InvalidArgument, "%s", err.Error())
+	}
+	return imgDownload, nil
+}
+
+func (agent *Agent) updateImageDownload(ctx context.Context, img *voltha.ImageDownload) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("updating-image-download", log.Fields{"device-id": agent.deviceID, "img": img})
+
+	cloned := agent.getDeviceWithoutLock()
+
+	// Update the image as well as remove it if the download was cancelled
+	clonedImages := make([]*voltha.ImageDownload, len(cloned.ImageDownloads))
+	for _, image := range cloned.ImageDownloads {
+		if image.Id == img.Id && image.Name == img.Name {
+			if image.DownloadState != voltha.ImageDownload_DOWNLOAD_CANCELLED {
+				clonedImages = append(clonedImages, img)
+			}
+		}
+	}
+	cloned.ImageDownloads = clonedImages
+	// Set the Admin state to enabled if required
+	if (img.DownloadState != voltha.ImageDownload_DOWNLOAD_REQUESTED &&
+		img.DownloadState != voltha.ImageDownload_DOWNLOAD_STARTED) ||
+		(img.ImageState != voltha.ImageDownload_IMAGE_ACTIVATING) {
+		return agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, voltha.AdminState_ENABLED, cloned.ConnectStatus, cloned.OperStatus)
+	}
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) getImageDownload(ctx context.Context, img *voltha.ImageDownload) (*voltha.ImageDownload, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("getImageDownload", log.Fields{"device-id": agent.deviceID})
+
+	cloned := agent.getDeviceWithoutLock()
+	for _, image := range cloned.ImageDownloads {
+		if image.Id == img.Id && image.Name == img.Name {
+			return image, nil
+		}
+	}
+	return nil, status.Errorf(codes.NotFound, "image-not-found:%s", img.Name)
+}
+
+func (agent *Agent) listImageDownloads(ctx context.Context, deviceID string) (*voltha.ImageDownloads, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("listImageDownloads", log.Fields{"device-id": agent.deviceID})
+
+	return &voltha.ImageDownloads{Items: agent.getDeviceWithoutLock().ImageDownloads}, nil
+}
+
+// getPorts retrieves the ports information of the device based on the port type.
+func (agent *Agent) getPorts(ctx context.Context, portType voltha.Port_PortType) *voltha.Ports {
+	logger.Debugw("getPorts", log.Fields{"device-id": agent.deviceID, "port-type": portType})
+	ports := &voltha.Ports{}
+	if device, _ := agent.deviceMgr.GetDevice(ctx, agent.deviceID); device != nil {
+		for _, port := range device.Ports {
+			if port.Type == portType {
+				ports.Items = append(ports.Items, port)
+			}
+		}
+	}
+	return ports
+}
+
+// getSwitchCapability retrieves the switch capability of a parent device
+func (agent *Agent) getSwitchCapability(ctx context.Context) (*ic.SwitchCapability, error) {
+	logger.Debugw("getSwitchCapability", log.Fields{"device-id": agent.deviceID})
+
+	cloned, err := agent.getDevice(ctx)
+	if err != nil {
+		return nil, err
+	}
+	ch, err := agent.adapterProxy.GetOfpDeviceInfo(ctx, cloned)
+	if err != nil {
+		return nil, err
+	}
+
+	// Wait for adapter response
+	rpcResponse, ok := <-ch
+	if !ok {
+		return nil, status.Errorf(codes.Aborted, "channel-closed")
+	}
+	if rpcResponse.Err != nil {
+		return nil, rpcResponse.Err
+	}
+	// Successful response
+	switchCap := &ic.SwitchCapability{}
+	if err := ptypes.UnmarshalAny(rpcResponse.Reply, switchCap); err != nil {
+		return nil, err
+	}
+	return switchCap, nil
+}
+
+// getPortCapability retrieves the port capability of a device
+func (agent *Agent) getPortCapability(ctx context.Context, portNo uint32) (*ic.PortCapability, error) {
+	logger.Debugw("getPortCapability", log.Fields{"device-id": agent.deviceID})
+	device, err := agent.getDevice(ctx)
+	if err != nil {
+		return nil, err
+	}
+	ch, err := agent.adapterProxy.GetOfpPortInfo(ctx, device, portNo)
+	if err != nil {
+		return nil, err
+	}
+	// Wait for adapter response
+	rpcResponse, ok := <-ch
+	if !ok {
+		return nil, status.Errorf(codes.Aborted, "channel-closed")
+	}
+	if rpcResponse.Err != nil {
+		return nil, rpcResponse.Err
+	}
+	// Successful response
+	portCap := &ic.PortCapability{}
+	if err := ptypes.UnmarshalAny(rpcResponse.Reply, portCap); err != nil {
+		return nil, status.Errorf(codes.InvalidArgument, "%s", err.Error())
+	}
+	return portCap, nil
+}
+
+func (agent *Agent) onPacketFailure(rpc string, response interface{}, args ...interface{}) {
+	// packet data is encoded in the args param as the first parameter
+	var packet []byte
+	if len(args) >= 1 {
+		if pkt, ok := args[0].([]byte); ok {
+			packet = pkt
+		}
+	}
+	var errResp error
+	if err, ok := response.(error); ok {
+		errResp = err
+	}
+	logger.Warnw("packet-out-error", log.Fields{
+		"device-id": agent.deviceID,
+		"error":     errResp,
+		"packet":    hex.EncodeToString(packet),
+	})
+}
+
+func (agent *Agent) packetOut(ctx context.Context, outPort uint32, packet *ofp.OfpPacketOut) error {
+	// If deviceType=="" then we must have taken ownership of this device.
+	// Fixes VOL-2226 where a core would take ownership and have stale data
+	if agent.deviceType == "" {
+		agent.reconcileWithKVStore(ctx)
+	}
+	//	Send packet to adapter
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.PacketOut(subCtx, agent.deviceType, agent.deviceID, outPort, packet)
+	if err != nil {
+		cancel()
+		return nil
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "packetOut", ch, agent.onSuccess, agent.onPacketFailure, packet.Data)
+	return nil
+}
+
+// updatePartialDeviceData updates a subset of a device that an Adapter can update.
+// TODO:  May need a specific proto to handle only a subset of a device that can be changed by an adapter
+func (agent *Agent) mergeDeviceInfoFromAdapter(device *voltha.Device) (*voltha.Device, error) {
+	cloned := agent.getDeviceWithoutLock()
+	cloned.Root = device.Root
+	cloned.Vendor = device.Vendor
+	cloned.Model = device.Model
+	cloned.SerialNumber = device.SerialNumber
+	cloned.MacAddress = device.MacAddress
+	cloned.Vlan = device.Vlan
+	cloned.Reason = device.Reason
+	return cloned, nil
+}
+
+func (agent *Agent) updateDeviceUsingAdapterData(ctx context.Context, device *voltha.Device) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("updateDeviceUsingAdapterData", log.Fields{"device-id": device.Id})
+
+	updatedDevice, err := agent.mergeDeviceInfoFromAdapter(device)
+	if err != nil {
+		return status.Errorf(codes.Internal, "%s", err.Error())
+	}
+	cloned := proto.Clone(updatedDevice).(*voltha.Device)
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) updateDeviceWithoutLock(ctx context.Context, device *voltha.Device) error {
+	logger.Debugw("updateDevice", log.Fields{"deviceId": device.Id})
+	//cloned := proto.Clone(device).(*voltha.Device)
+	cloned := device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) updateDeviceStatus(ctx context.Context, operStatus voltha.OperStatus_Types, connStatus voltha.ConnectStatus_Types) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	cloned := agent.getDeviceWithoutLock()
+
+	newConnStatus, newOperStatus := cloned.ConnectStatus, cloned.OperStatus
+	// Ensure the enums passed in are valid - they will be invalid if they are not set when this function is invoked
+	if s, ok := voltha.ConnectStatus_Types_value[connStatus.String()]; ok {
+		logger.Debugw("updateDeviceStatus-conn", log.Fields{"ok": ok, "val": s})
+		newConnStatus = connStatus
+	}
+	if s, ok := voltha.OperStatus_Types_value[operStatus.String()]; ok {
+		logger.Debugw("updateDeviceStatus-oper", log.Fields{"ok": ok, "val": s})
+		newOperStatus = operStatus
+	}
+	logger.Debugw("updateDeviceStatus", log.Fields{"deviceId": cloned.Id, "operStatus": cloned.OperStatus, "connectStatus": cloned.ConnectStatus})
+	// Store the device
+	return agent.updateDeviceStateInStoreWithoutLock(ctx, cloned, cloned.AdminState, newConnStatus, newOperStatus)
+}
+
+func (agent *Agent) updatePortsOperState(ctx context.Context, operStatus voltha.OperStatus_Types) error {
+	logger.Debugw("updatePortsOperState", log.Fields{"device-id": agent.deviceID})
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	cloned := agent.getDeviceWithoutLock()
+	for _, port := range cloned.Ports {
+		port.OperStatus = operStatus
+	}
+	// Store the device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) updatePortState(ctx context.Context, portType voltha.Port_PortType, portNo uint32, operStatus voltha.OperStatus_Types) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	// Work only on latest data
+	// TODO: Get list of ports from device directly instead of the entire device
+	cloned := agent.getDeviceWithoutLock()
+
+	// Ensure the enums passed in are valid - they will be invalid if they are not set when this function is invoked
+	if _, ok := voltha.Port_PortType_value[portType.String()]; !ok {
+		return status.Errorf(codes.InvalidArgument, "%s", portType)
+	}
+	for _, port := range cloned.Ports {
+		if port.Type == portType && port.PortNo == portNo {
+			port.OperStatus = operStatus
+		}
+	}
+	logger.Debugw("portStatusUpdate", log.Fields{"deviceId": cloned.Id})
+	// Store the device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) deleteAllPorts(ctx context.Context) error {
+	logger.Debugw("deleteAllPorts", log.Fields{"deviceId": agent.deviceID})
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	cloned := agent.getDeviceWithoutLock()
+
+	if cloned.AdminState != voltha.AdminState_DISABLED && cloned.AdminState != voltha.AdminState_DELETED {
+		err := status.Error(codes.FailedPrecondition, fmt.Sprintf("invalid-state-%v", cloned.AdminState))
+		logger.Warnw("invalid-state-removing-ports", log.Fields{"state": cloned.AdminState, "error": err})
+		return err
+	}
+	if len(cloned.Ports) == 0 {
+		logger.Debugw("no-ports-present", log.Fields{"deviceId": agent.deviceID})
+		return nil
+	}
+
+	cloned.Ports = []*voltha.Port{}
+	logger.Debugw("portStatusUpdate", log.Fields{"deviceId": cloned.Id})
+	// Store the device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) addPort(ctx context.Context, port *voltha.Port) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("addPort", log.Fields{"deviceId": agent.deviceID})
+
+	cloned := agent.getDeviceWithoutLock()
+	updatePort := false
+	if cloned.Ports == nil {
+		//	First port
+		logger.Debugw("addPort-first-port-to-add", log.Fields{"deviceId": agent.deviceID})
+		cloned.Ports = make([]*voltha.Port, 0)
+	} else {
+		for _, p := range cloned.Ports {
+			if p.Type == port.Type && p.PortNo == port.PortNo {
+				if p.Label == "" && p.Type == voltha.Port_PON_OLT {
+					//Creation of OLT PON port is being processed after a default PON port was created.  Just update it.
+					logger.Infow("update-pon-port-created-by-default", log.Fields{"default-port": p, "port-to-add": port})
+					p.Label = port.Label
+					p.OperStatus = port.OperStatus
+					updatePort = true
+					break
+				}
+				logger.Debugw("port already exists", log.Fields{"port": port})
+				return nil
+			}
+		}
+	}
+	if !updatePort {
+		cp := proto.Clone(port).(*voltha.Port)
+		// Set the admin state of the port to ENABLE
+		cp.AdminState = voltha.AdminState_ENABLED
+		cloned.Ports = append(cloned.Ports, cp)
+	}
+	// Store the device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) addPeerPort(ctx context.Context, peerPort *voltha.Port_PeerPort) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("adding-peer-peerPort", log.Fields{"device-id": agent.deviceID, "peer-peerPort": peerPort})
+
+	cloned := agent.getDeviceWithoutLock()
+
+	// Get the peer port on the device based on the peerPort no
+	found := false
+	for _, port := range cloned.Ports {
+		if port.PortNo == peerPort.PortNo { // found peerPort
+			cp := proto.Clone(peerPort).(*voltha.Port_PeerPort)
+			port.Peers = append(port.Peers, cp)
+			logger.Debugw("found-peer", log.Fields{"device-id": agent.deviceID, "portNo": peerPort.PortNo, "deviceId": agent.deviceID})
+			found = true
+			break
+		}
+	}
+	if !found && agent.isRootdevice {
+		// An ONU PON port has been created before the corresponding creation of the OLT PON port.  Create the OLT PON port
+		// with default values which will be updated once the OLT PON port creation is processed.
+		ponPort := &voltha.Port{
+			PortNo:     peerPort.PortNo,
+			Type:       voltha.Port_PON_OLT,
+			AdminState: voltha.AdminState_ENABLED,
+			DeviceId:   agent.deviceID,
+			Peers:      []*voltha.Port_PeerPort{proto.Clone(peerPort).(*voltha.Port_PeerPort)},
+		}
+		cloned.Ports = append(cloned.Ports, ponPort)
+		logger.Infow("adding-default-pon-port", log.Fields{"device-id": agent.deviceID, "peer": peerPort, "pon-port": ponPort})
+	}
+	// Store the device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+// TODO: A generic device update by attribute
+func (agent *Agent) updateDeviceAttribute(ctx context.Context, name string, value interface{}) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		logger.Warnw("request-aborted", log.Fields{"device-id": agent.deviceID, "name": name, "error": err})
+		return
+	}
+	defer agent.requestQueue.RequestComplete()
+	if value == nil {
+		return
+	}
+
+	cloned := agent.getDeviceWithoutLock()
+	updated := false
+	s := reflect.ValueOf(cloned).Elem()
+	if s.Kind() == reflect.Struct {
+		// exported field
+		f := s.FieldByName(name)
+		if f.IsValid() && f.CanSet() {
+			switch f.Kind() {
+			case reflect.String:
+				f.SetString(value.(string))
+				updated = true
+			case reflect.Uint32:
+				f.SetUint(uint64(value.(uint32)))
+				updated = true
+			case reflect.Bool:
+				f.SetBool(value.(bool))
+				updated = true
+			}
+		}
+	}
+	logger.Debugw("update-field-status", log.Fields{"deviceId": cloned.Id, "name": name, "updated": updated})
+	//	Save the data
+
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, ""); err != nil {
+		logger.Warnw("attribute-update-failed", log.Fields{"attribute": name, "value": value})
+	}
+}
+
+func (agent *Agent) simulateAlarm(ctx context.Context, simulatereq *voltha.SimulateAlarmRequest) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("simulateAlarm", log.Fields{"id": agent.deviceID})
+
+	cloned := agent.getDeviceWithoutLock()
+
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.SimulateAlarm(subCtx, cloned, simulatereq)
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "simulateAlarm", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) updateDeviceStateInStoreWithoutLock(
+	ctx context.Context,
+	device *voltha.Device,
+	adminState voltha.AdminState_Types,
+	connectStatus voltha.ConnectStatus_Types,
+	operStatus voltha.OperStatus_Types,
+) error {
+	previousState := getDeviceStates(device)
+	device.AdminState, device.ConnectStatus, device.OperStatus = adminState, connectStatus, operStatus
+
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, device, false, ""); err != nil {
+		return err
+	}
+
+	// process state transition in its own thread
+	go func() {
+		if err := agent.deviceMgr.processTransition(context.Background(), device, previousState); err != nil {
+			log.Errorw("failed-process-transition", log.Fields{"deviceId": device.Id, "previousAdminState": previousState.Admin, "currentAdminState": device.AdminState})
+		}
+	}()
+	return nil
+}
+
+//This is an update operation to model without Lock.This function must never be invoked by another function unless the latter holds a lock on the device.
+// It is an internal helper function.
+func (agent *Agent) updateDeviceInStoreWithoutLock(ctx context.Context, device *voltha.Device, strict bool, txid string) error {
+	if agent.stopped {
+		return errors.New("device agent stopped")
+	}
+
+	updateCtx := context.WithValue(ctx, model.RequestTimestamp, time.Now().UnixNano())
+	if err := agent.clusterDataProxy.Update(updateCtx, "devices/"+agent.deviceID, device); err != nil {
+		return status.Errorf(codes.Internal, "failed-update-device:%s: %s", agent.deviceID, err)
+	}
+	logger.Debugw("updated-device-in-store", log.Fields{"deviceId: ": agent.deviceID})
+
+	agent.device = proto.Clone(device).(*voltha.Device)
+	return nil
+}
+
+func (agent *Agent) updateDeviceReason(ctx context.Context, reason string) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	cloned := agent.getDeviceWithoutLock()
+	cloned.Reason = reason
+	logger.Debugw("updateDeviceReason", log.Fields{"deviceId": cloned.Id, "reason": cloned.Reason})
+	// Store the device
+	return agent.updateDeviceInStoreWithoutLock(ctx, cloned, false, "")
+}
+
+func (agent *Agent) disablePort(ctx context.Context, Port *voltha.Port) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("disablePort", log.Fields{"device-id": agent.deviceID, "port-no": Port.PortNo})
+	var cp *voltha.Port
+	// Get the most up to date the device info
+	device := agent.getDeviceWithoutLock()
+	for _, port := range device.Ports {
+		if port.PortNo == Port.PortNo {
+			port.AdminState = voltha.AdminState_DISABLED
+			cp = proto.Clone(port).(*voltha.Port)
+			break
+
+		}
+	}
+	if cp == nil {
+		return status.Errorf(codes.InvalidArgument, "%v", Port.PortNo)
+	}
+
+	if cp.Type != voltha.Port_PON_OLT {
+		return status.Errorf(codes.InvalidArgument, "Disabling of Port Type %v unimplemented", cp.Type)
+	}
+	// Store the device
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, device, false, ""); err != nil {
+		logger.Debugw("updateDeviceInStoreWithoutLock error ", log.Fields{"device-id": agent.deviceID, "port-no": Port.PortNo, "error": err})
+		return err
+	}
+
+	//send request to adapter
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.DisablePort(ctx, device, cp)
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "disablePort", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) enablePort(ctx context.Context, Port *voltha.Port) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+	logger.Debugw("enablePort", log.Fields{"device-id": agent.deviceID, "port-no": Port.PortNo})
+
+	var cp *voltha.Port
+	// Get the most up to date the device info
+	device := agent.getDeviceWithoutLock()
+	for _, port := range device.Ports {
+		if port.PortNo == Port.PortNo {
+			port.AdminState = voltha.AdminState_ENABLED
+			cp = proto.Clone(port).(*voltha.Port)
+			break
+		}
+	}
+
+	if cp == nil {
+		return status.Errorf(codes.InvalidArgument, "%v", Port.PortNo)
+	}
+
+	if cp.Type != voltha.Port_PON_OLT {
+		return status.Errorf(codes.InvalidArgument, "Enabling of Port Type %v unimplemented", cp.Type)
+	}
+	// Store the device
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, device, false, ""); err != nil {
+		logger.Debugw("updateDeviceInStoreWithoutLock error ", log.Fields{"device-id": agent.deviceID, "port-no": Port.PortNo, "error": err})
+		return err
+	}
+	//send request to adapter
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.EnablePort(ctx, device, cp)
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "enablePort", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) ChildDeviceLost(ctx context.Context, device *voltha.Device) error {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return err
+	}
+	defer agent.requestQueue.RequestComplete()
+
+	logger.Debugw("childDeviceLost", log.Fields{"child-device-id": device.Id, "parent-device-ud": agent.deviceID})
+
+	//Remove the associated peer ports on the parent device
+	parentDevice := agent.getDeviceWithoutLock()
+	var updatedPeers []*voltha.Port_PeerPort
+	for _, port := range parentDevice.Ports {
+		updatedPeers = make([]*voltha.Port_PeerPort, 0)
+		for _, peerPort := range port.Peers {
+			if peerPort.DeviceId != device.Id {
+				updatedPeers = append(updatedPeers, peerPort)
+			}
+		}
+		port.Peers = updatedPeers
+	}
+	if err := agent.updateDeviceInStoreWithoutLock(ctx, parentDevice, false, ""); err != nil {
+		return err
+	}
+
+	//send request to adapter
+	subCtx, cancel := context.WithTimeout(context.Background(), agent.defaultTimeout)
+	ch, err := agent.adapterProxy.ChildDeviceLost(ctx, agent.deviceType, agent.deviceID, device.ParentPortNo, device.ProxyAddress.OnuId)
+	if err != nil {
+		cancel()
+		return err
+	}
+	go agent.waitForAdapterResponse(subCtx, cancel, "childDeviceLost", ch, agent.onSuccess, agent.onFailure)
+	return nil
+}
+
+func (agent *Agent) startOmciTest(ctx context.Context, omcitestrequest *voltha.OmciTestRequest) (*voltha.TestResponse, error) {
+	if err := agent.requestQueue.WaitForGreenLight(ctx); err != nil {
+		return nil, err
+	}
+
+	device := agent.getDeviceWithoutLock()
+
+	if device.Adapter == "" {
+		adapterName, err := agent.adapterMgr.GetAdapterType(device.Type)
+		if err != nil {
+			agent.requestQueue.RequestComplete()
+			return nil, err
+		}
+		device.Adapter = adapterName
+	}
+
+	// Send request to the adapter
+	ch, err := agent.adapterProxy.StartOmciTest(ctx, device, omcitestrequest)
+	agent.requestQueue.RequestComplete()
+	if err != nil {
+		return nil, err
+	}
+
+	// Wait for the adapter response
+	rpcResponse, ok := <-ch
+	if !ok {
+		return nil, status.Errorf(codes.Aborted, "channel-closed-device-id-%s", agent.deviceID)
+	}
+	if rpcResponse.Err != nil {
+		return nil, rpcResponse.Err
+	}
+
+	// Unmarshal and return the response
+	testResp := &voltha.TestResponse{}
+	if err := ptypes.UnmarshalAny(rpcResponse.Reply, testResp); err != nil {
+		return nil, status.Errorf(codes.InvalidArgument, "%s", err.Error())
+	}
+	logger.Debugw("Omci_test_Request-Success-device-agent", log.Fields{"testResp": testResp})
+	return testResp, nil
+}