Cellular: added to reset state machine is we get disconnected so application can try again.

features/cellular/framework/AT/AT_CellularNetwork.cpp

@@ -73,12 +73,12 @@ AT_CellularNetwork::~AT_CellularNetwork()
 
     for (int type = 0; type < CellularNetwork::C_MAX; type++) {
         if (has_registration((RegistrationType)type) != RegistrationModeDisable) {
-            _at.remove_urc_handler(at_reg[type].urc_prefix, _urc_funcs[type]);
+            _at.remove_urc_handler(at_reg[type].urc_prefix);
         }
     }
 
-    _at.remove_urc_handler("NO CARRIER", callback(this, &AT_CellularNetwork::urc_no_carrier));
+    _at.remove_urc_handler("NO CARRIER");
-    _at.remove_urc_handler("+CGEV:", callback(this, &AT_CellularNetwork::urc_cgev));
+    _at.remove_urc_handler("+CGEV:");
 }
 
 void AT_CellularNetwork::urc_no_carrier()

features/cellular/framework/device/CellularDevice.cpp

@@ -184,6 +184,12 @@ void CellularDevice::cellular_callback(nsapi_event_t ev, intptr_t ptr)
         }
     } else {
         tr_debug("Device: network_callback called with event: %d, ptr: %d", ev, ptr);
+        if (ev == NSAPI_EVENT_CONNECTION_STATUS_CHANGE && ptr == NSAPI_STATUS_DISCONNECTED) {
+            // we have been disconnected, reset state machine so that application can start connect sequence again
+            if (_state_machine) {
+                _state_machine->reset();
+            }
+        }
     }
 
     // broadcast network and cellular changes to state machine and CellularContext.

features/cellular/framework/device/CellularStateMachine.cpp

@@ -74,6 +74,17 @@ CellularStateMachine::~CellularStateMachine()
     stop();
 }
 
+void CellularStateMachine::reset()
+{
+    _state = STATE_INIT;
+    _event_timeout = -1;
+    _event_id = -1;
+    _plmn_network_found = false;
+    _is_retry = false;
+    _active_context = false;
+    enter_to_state(STATE_INIT);
+}
+
 void CellularStateMachine::stop()
 {
     _queue.cancel(_event_id);
@@ -85,15 +96,7 @@ void CellularStateMachine::stop()
         _queue_thread = NULL;
     }
 
-    _state = STATE_INIT;
+    reset();
-    _next_state = _state;
-    _target_state = _state;
-    _cb_data.error = NSAPI_ERROR_OK;
-    _cb_data.status_data = -1;
-    _cb_data.final_try = false;
-    _event_id = -1;
-    _is_retry = false;
-
     if (_power) {
         _cellularDevice.close_power();
         _power = NULL;

features/cellular/framework/device/CellularStateMachine.h

@@ -135,6 +135,9 @@ private:
      */
     void cellular_event_changed(nsapi_event_t ev, intptr_t ptr);
 
+    /** Reset the state machine to init state. After reset state machine can be used again to run to wanted state.
+     */
+    void reset();
 private:
     bool power_on();
     bool open_sim();