Added cellular stack API

features/cellular/easy_cellular/CellularConnectionUtil.cpp

@@ -533,3 +533,8 @@ CellularDevice* CellularConnectionUtil::get_device()
         return NULL;
     }
 }
+
+NetworkStack *CellularConnectionUtil::get_stack()
+{
+    return _cellularDevice->get_stack();
+}

features/cellular/easy_cellular/CellularConnectionUtil.h

@@ -76,6 +76,10 @@ protected:
     bool get_attach_network(CellularNetwork::AttachStatus &status);
     bool set_attach_network();
 
+protected:
+    friend class EasyCellularConnection;
+    NetworkStack *get_stack();
+
 private:
     void device_ready();
     void report_failure(const char* msg);

features/cellular/easy_cellular/EasyCellularConnection.cpp

@@ -149,6 +149,6 @@ NetworkStack *EasyCellularConnection::get_stack()
 #if NSAPI_PPP_AVAILABLE
     return nsapi_ppp_get_stack();
 #else
-    return NULL;//cellularConnection.get_network();
+    return cellularConnection.get_stack();
 #endif // #if NSAPI_PPP_AVAILABLE
 }

features/cellular/framework/API/CellularDevice.h

@@ -26,6 +26,7 @@
 #include "CellularPower.h"
 #include "CellularMultiplexer.h"
 #include "CellularInformation.h"
+#include "NetworkStack.h"
 
 namespace mbed {
 
@@ -114,6 +115,12 @@ public:
      *  @param timeout    milliseconds to wait response from modem
      */
     virtual void set_timeout(int timeout) = 0;
+    
+    /** Get network stack.
+     *
+     *  @return network stack
+     */
+    virtual NetworkStack *get_stack() = 0;
 };
 
 } // namespace mbed

features/cellular/framework/AT/AT_CellularDevice.cpp

@@ -246,3 +246,11 @@ void AT_CellularDevice::set_timeout(int timeout)
         atHandler = atHandler->_nextATHandler;
     }
 }
+
+NetworkStack *AT_CellularDevice::get_stack()
+{
+    if (!_network) {
+        return NULL;
+    }
+    return _network->get_stack();
+}

features/cellular/framework/AT/AT_CellularDevice.h

@@ -127,6 +127,12 @@ public: // CellularDevice
      */
     virtual void set_timeout(int timeout);
 
+    /** Get network stack.
+     *
+     *  @return network stack
+     */
+    NetworkStack *get_stack();
+    
 protected:
     AT_CellularNetwork *_network;
     AT_CellularSMS *_sms;