APN lookup from database support.

Author: Teppo Järvelin

features/cellular/easy_cellular/CellularConnectionUtil.cpp

@@ -36,7 +36,7 @@ static CELLULAR_DEVICE cellularDevice(at_queue);
 static char device_info_buf[2048];
 
 CellularConnectionUtil::CellularConnectionUtil() : _serial(0), _state(STATE_POWER_ON), _next_state(_state),
-        _status_callback(0), _network(0), _power(0), _queue(8 * EVENTS_EVENT_SIZE),
+        _status_callback(0), _network(0), _power(0), _sim(0), _queue(8 * EVENTS_EVENT_SIZE),
         _queue_thread(0), _cellularDevice(&cellularDevice)
 {
     memset(_sim_pin, 0, sizeof(_sim_pin));
@@ -60,6 +60,12 @@ nsapi_error_t CellularConnectionUtil::init()
         return NSAPI_ERROR_NO_MEMORY;
     }
 
+    _sim = _cellularDevice->open_sim(_serial);
+    if (!_sim) {
+        stop();
+        return NSAPI_ERROR_NO_MEMORY;
+    }
+
     at_queue.chain(&_queue);
 
     tr_info("init done...");
@@ -94,43 +100,38 @@ void CellularConnectionUtil::set_sim_pin(const char * sim_pin)
 
 bool CellularConnectionUtil::open_sim()
 {
+    CellularSIM::SimState state = CellularSIM::SimStateUnknown;
+    // wait until SIM is readable
+    // here you could add wait(secs) if you know start delay of your SIM
+    while (_sim->get_sim_state(state) != NSAPI_ERROR_OK || state == CellularSIM::SimStateUnknown) {
+        tr_info("Waiting for SIM (state %d)...", state);
+        return false;
+    }
+    tr_info("Initial SIM state: %d", state);
+
     if (strlen(_sim_pin)) {
         nsapi_error_t err;
-        static CellularSIM *sim;
-        if (!sim) {
-            sim = _cellularDevice->open_sim(_serial);
-        }
-        if (!sim) {
-            return false;
-        }
-        CellularSIM::SimState state = CellularSIM::SimStateUnknown;
-        // wait until SIM is readable
-        // here you could add wait(secs) if you know start delay of your SIM
-        while (sim->get_sim_state(state) != NSAPI_ERROR_OK || state == CellularSIM::SimStateUnknown) {
-            tr_debug("Waiting for SIM (state %d)...", state);
-            return false;
-        }
         if (state == CellularSIM::SimStatePinNeeded) {
             tr_info("SIM pin required, entering pin: %s", _sim_pin);
-            err = sim->set_pin(_sim_pin);
+            err = _sim->set_pin(_sim_pin);
             if (err) {
                 tr_error("SIM pin set failed with: %d, bailing out...", err);
                 return false;
             }
             // here you could add wait(secs) if you know delay of changing PIN on your SIM
             for (int i = 0; i < MAX_SIM_READY_WAITING_TIME; i++) {
-                if (sim->get_sim_state(state) == NSAPI_ERROR_OK && state == CellularSIM::SimStateReady) {
+                if (_sim->get_sim_state(state) == NSAPI_ERROR_OK && state == CellularSIM::SimStateReady) {
                     break;
                 }
                 tr_debug("SIM state: %d", state);
                 return false;
             }
         }
-        return state == CellularSIM::SimStateReady;
     } else {
-        tr_info("Continue without SIM.");
-        return true;
+        tr_info("No SIM pin provided.");
     }
+
+    return state == CellularSIM::SimStateReady;
 }
 
 void CellularConnectionUtil::device_ready()
@@ -506,6 +507,11 @@ CellularDevice* CellularConnectionUtil::get_device()
     return _cellularDevice;
 }
 
+CellularSIM* CellularConnectionUtil::get_sim()
+{
+    return _sim;
+}
+
 NetworkStack *CellularConnectionUtil::get_stack()
 {
     return _cellularDevice->get_stack();

features/cellular/easy_cellular/CellularConnectionUtil.h

@@ -28,6 +28,7 @@
 
 #include "CellularNetwork.h"
 #include "CellularPower.h"
+#include "CellularSIM.h"
 
 // modem type is defined as CELLULAR_DEVICE macro
 #define _CELLULAR_STRINGIFY(a) #a
@@ -105,6 +106,11 @@ class CellularConnectionUtil
      */
     CellularDevice* get_device();
 
+    /** Get cellular sim interface
+     *  @return sim interface, NULL on failure
+     */
+    CellularSIM* get_sim();
+
     /** Change cellular connection to the target state
      *  @param state to continue
      *  @return see nsapi_error_t, 0 on success
@@ -142,6 +148,7 @@ class CellularConnectionUtil
 
     CellularNetwork *_network;
     CellularPower *_power;
+    CellularSIM *_sim;
     events::EventQueue _queue;
     rtos::Thread *_queue_thread;
     CellularDevice *_cellularDevice;

features/cellular/easy_cellular/EasyCellularConnection.cpp

@@ -26,9 +26,12 @@
 #include "CellularUtil.h"
 
 #include "EasyCellularConnection.h"
-
 #include "CellularLog.h"
 
+#if MBED_CONF_APP_CELLULAR_USE_APN_LOOKUP
+#include "APN_db.h"
+#endif //MBED_CONF_APP_CELLULAR_USE_APN_LOOKUP
+
 namespace mbed {
 
 bool EasyCellularConnection::cellular_status(int state, int next_state)
@@ -50,7 +53,7 @@ bool EasyCellularConnection::cellular_status(int state, int next_state)
 }
 
 EasyCellularConnection::EasyCellularConnection() :  _is_connected(false), _is_initialized(false),
-        _target_state(CellularConnectionUtil::STATE_POWER_ON),
+        _credentials_set(false), _target_state(CellularConnectionUtil::STATE_POWER_ON),
         _cellularSerial(MDMTXD, MDMRXD, MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE),
         _cellularSemaphore(0), _cellularConnectionUtil(), _credentials_err(NSAPI_ERROR_OK)
 {
@@ -67,7 +70,7 @@ nsapi_error_t EasyCellularConnection::init()
     nsapi_error_t err = NSAPI_ERROR_OK;
     if (!_is_initialized) {
 #if defined (MDMRTS) && defined (MDMCTS)
-    _cellularSerial.set_flow_control(SerialBase::RTSCTS, MDMRTS, MDMCTS);
+        _cellularSerial.set_flow_control(SerialBase::RTSCTS, MDMRTS, MDMCTS);
 #endif
         _cellularConnectionUtil.set_serial(&_cellularSerial);
         _cellularConnectionUtil.set_callback(callback(this, &EasyCellularConnection::cellular_status));
@@ -85,16 +88,21 @@ nsapi_error_t EasyCellularConnection::init()
 
 void EasyCellularConnection::set_credentials(const char *apn, const char *uname, const char *pwd)
 {
-    _credentials_err = init();
+    if (apn && strlen(apn) > 0) {
+        _credentials_err = init();
 
-    if (_credentials_err) {
-        return;
-    }
-    CellularNetwork * network = _cellularConnectionUtil.get_network();
-    if (network) {
-        _credentials_err = network->set_credentials(apn, uname, pwd);
-    } else {
-        tr_error("NO Network...");
+        if (_credentials_err) {
+            return;
+        }
+        CellularNetwork * network = _cellularConnectionUtil.get_network();
+        if (network) {
+            _credentials_err = network->set_credentials(apn, uname, pwd);
+            if (_credentials_err == NSAPI_ERROR_OK) {
+                _credentials_set = true;
+            }
+        } else {
+            tr_error("NO Network...");
+        }
     }
 }
 
@@ -107,18 +115,17 @@ void EasyCellularConnection::set_sim_pin(const char *sim_pin)
 
 nsapi_error_t EasyCellularConnection::connect(const char *sim_pin, const char *apn, const char *uname, const char *pwd)
 {
-    nsapi_error_t err = check_connect();
-    if (err) {
-        return err;
+    if (_is_connected) {
+        return NSAPI_ERROR_IS_CONNECTED;
     }
 
-    if (sim_pin) {
-        _cellularConnectionUtil.set_sim_pin(sim_pin);
+    set_credentials(apn, uname, pwd);
+    if (_credentials_err) {
+        return _credentials_err;
     }
 
-    err = _cellularConnectionUtil.get_network()->set_credentials(apn, uname, pwd);
-    if (err) {
-        return err;
+    if (sim_pin) {
+        _cellularConnectionUtil.set_sim_pin(sim_pin);
     }
 
     return connect();
@@ -129,6 +136,12 @@ nsapi_error_t EasyCellularConnection::check_connect()
     if (_is_connected) {
         return NSAPI_ERROR_IS_CONNECTED;
     }
+
+    // there was an error while setting credentials but it's a void function so check error here...
+    if (_credentials_err) {
+        return _credentials_err;
+    }
+
     nsapi_error_t err = init();
     if (err) {
         return err;
@@ -139,15 +152,39 @@ nsapi_error_t EasyCellularConnection::check_connect()
 
 nsapi_error_t EasyCellularConnection::connect()
 {
-    // there was an error while setting credentials but it's a void function so check error here...
-    if (_credentials_err) {
-        return _credentials_err;
-    }
-
     nsapi_error_t err = check_connect();
     if (err) {
         return err;
     }
+#if MBED_CONF_APP_CELLULAR_USE_APN_LOOKUP
+    if (!_credentials_set) {
+        _target_state = CellularConnectionUtil::STATE_SIM_PIN;
+        err = _cellularConnectionUtil.continue_to_state(_target_state);
+        if (err == NSAPI_ERROR_OK) {
+            int sim_wait = _cellularSemaphore.wait(6*1000); // reserve 6 seconds to access to SIM
+            if (sim_wait != 1) {
+                tr_error("NO SIM ACCESS");
+                err = NSAPI_ERROR_NO_CONNECTION;
+            } else {
+                char imsi[MAX_IMSI_LENGTH+1];
+                err = _cellularConnectionUtil.get_sim()->get_imsi(imsi);
+                if (err == NSAPI_ERROR_OK) {
+                    const char *apn_config = apnconfig(imsi);
+                    if (apn_config) {
+                        const char* apn = _APN_GET(apn_config);
+                        const char* uname = _APN_GET(apn_config);
+                        const char* pwd = _APN_GET(apn_config);
+                        tr_info("Looked up APN %s", apn);
+                        err = _cellularConnectionUtil.get_network()->set_credentials(apn, uname, pwd);
+                    }
+                }
+            }
+        }
+        if (err) {
+            return err;
+        }
+    }
+#endif // MBED_CONF_APP_CELLULAR_USE_APN_LOOKUP
 
     _target_state = CellularConnectionUtil::STATE_CONNECTED;
     err = _cellularConnectionUtil.continue_to_state(_target_state);
@@ -166,6 +203,7 @@ nsapi_error_t EasyCellularConnection::disconnect()
 {
     _credentials_err = NSAPI_ERROR_OK;
     _is_connected = false;
+    _credentials_set = false;
     if (!_cellularConnectionUtil.get_network()) {
         return NSAPI_ERROR_NO_CONNECTION;
     }

features/cellular/easy_cellular/EasyCellularConnection.h

@@ -136,6 +136,7 @@ class EasyCellularConnection: public CellularBase {
 
     bool _is_connected;
     bool _is_initialized;
+    bool _credentials_set;
     CellularConnectionUtil::CellularState _target_state;
 
     UARTSerial _cellularSerial;

features/cellular/framework/API/CellularSIM.h

@@ -23,7 +23,7 @@
 namespace mbed {
 
 const int MAX_SIM_READY_WAITING_TIME = 30;
-
+const int MAX_IMSI_LENGTH = 15;
 /**
  *  Class CellularSIM
  *
@@ -78,6 +78,13 @@ class CellularSIM
      *  @return         zero on success
      */
     virtual nsapi_error_t get_sim_state(SimState &state) = 0;
+
+    /** Get IMSI from the sim card
+     *
+     *  @param imsi     preallocated char* which after successful request contains imsi
+     *  @return         zero on success
+     */
+    virtual nsapi_error_t get_imsi(char* imsi) = 0;
 };
 
 } // namespace mbed

features/cellular/framework/AT/AT_CellularSIM.cpp

@@ -114,3 +114,17 @@ nsapi_error_t AT_CellularSIM::set_pin_query(const char *sim_pin, bool query_pin)
     }
     return _at.unlock_return_error();
 }
+
+nsapi_error_t AT_CellularSIM::get_imsi(char* imsi)
+{
+    _at.lock();
+    _at.cmd_start("AT+CIMI");
+    _at.cmd_stop();
+    _at.resp_start();
+    int len = _at.read_string(imsi, MAX_IMSI_LENGTH);
+    if (len > 0) {
+        imsi[len] = '\0';
+    }
+    _at.resp_stop();
+    return _at.unlock_return_error();
+}

features/cellular/framework/AT/AT_CellularSIM.h

@@ -43,6 +43,8 @@ class AT_CellularSIM : public CellularSIM, public AT_CellularBase
     virtual nsapi_error_t set_pin_query(const char *sim_pin, bool query_pin);
 
     virtual nsapi_error_t get_sim_state(SimState &state);
+
+    virtual nsapi_error_t get_imsi(char* imsi);
 };
 
 } // namespace mbed