GSM: allow retry if connection fails

libraries/GSM/src/GSM.cpp

@@ -46,10 +46,26 @@ mbed::CellularDevice *mbed::CellularDevice::get_default_instance()
 
 int arduino::GSMClass::begin(const char* pin, const char* apn, const char* username, const char* password, RadioAccessTechnologyType rat, uint32_t band, bool restart) {
 
+  /* Assume module is powered ON. Uncomment this line is you are using
+   * Edge Control without Arduino_ConnectionHandler
+   * #if defined (ARDUINO_EDGE_CONTROL)
+   *   pinMode(ON_MKR2, OUTPUT);
+   *   digitalWrite(ON_MKR2, HIGH);
+   * #endif
+   */
+
+  /* Ensure module is not under reset */
+  pinMode(MBED_CONF_GEMALTO_CINTERION_RST, OUTPUT);
+  digitalWrite(MBED_CONF_GEMALTO_CINTERION_RST, LOW);
+
+  /* Reset module if needed */
   if (restart || isCmuxEnable()) {
     reset();
   }
 
+  /* Create rising edge on pin ON */
+  on();
+
   if (!_context) {
     _context = mbed::CellularContext::get_default_instance();
   }
@@ -59,20 +75,17 @@ int arduino::GSMClass::begin(const char* pin, const char* apn, const char* usern
     return 0;
   }
 
-  pinMode(MBED_CONF_GEMALTO_CINTERION_ON, INPUT_PULLDOWN);
-
+#if defined(ARDUINO_PORTENTA_H7_M7) || defined(ARDUINO_PORTENTA_H7_M4)
+  /* This is needed to wakeup module if hw flow control is enabled */
   static mbed::DigitalOut rts(MBED_CONF_GEMALTO_CINTERION_RTS, 0);
+#endif
 
   _device = _context->get_device();
   _device->modem_debug_on(_at_debug);
 
-  if (!isReady()) {
-    DEBUG_ERROR("Cellular device not ready");
-    return 0;
-  }
-
   _device->set_cmux_status_flag(_cmuxGSMenable);
   _device->set_retry_timeout_array(_retry_timeout, sizeof(_retry_timeout) / sizeof(_retry_timeout[0]));
+  _device->set_timeout(_timeout);
   _device->attach(mbed::callback(this, &GSMClass::onStatusChange));
   _device->init();
 
@@ -106,6 +119,10 @@ int arduino::GSMClass::begin(const char* pin, const char* apn, const char* usern
   return connect_status == NSAPI_ERROR_OK ? 1 : 0;
 }
 
+void arduino::GSMClass::setTimeout(unsigned long timeout) {
+  _timeout = timeout;
+}
+
 void arduino::GSMClass::enableCmux() {
   _cmuxGSMenable = true;
 }
@@ -115,7 +132,7 @@ bool arduino::GSMClass::isCmuxEnable() {
 }
 
 void arduino::GSMClass::end() {
-
+  _device->shutdown();
 }
 
 int arduino::GSMClass::disconnect() {
@@ -159,33 +176,21 @@ NetworkInterface* arduino::GSMClass::getNetwork() {
 }
 
 void arduino::GSMClass::reset() {
+  /* Reset logic is inverted */
   pinMode(MBED_CONF_GEMALTO_CINTERION_RST, OUTPUT);
   digitalWrite(MBED_CONF_GEMALTO_CINTERION_RST, HIGH);
   delay(800);
   digitalWrite(MBED_CONF_GEMALTO_CINTERION_RST, LOW);
+}
+
+void arduino::GSMClass::on() {
+  /* Module needs a rising edge to power on */
   pinMode(MBED_CONF_GEMALTO_CINTERION_ON, OUTPUT);
   digitalWrite(MBED_CONF_GEMALTO_CINTERION_ON, LOW);
   delay(1);
   digitalWrite(MBED_CONF_GEMALTO_CINTERION_ON, HIGH);
   delay(1);
 }
 
-bool arduino::GSMClass::isReady(const int timeout) {
-  if (!_device) {
-    DEBUG_ERROR("No device found");
-    return false;
-  }
-
-  const unsigned int start = millis();
-  while (_device->is_ready() != NSAPI_ERROR_OK) {
-
-    if (millis() - start > timeout) {
-      DEBUG_WARNING("Timeout waiting device ready");
-      return false;
-    }
-    delay(100);
-  }
-  return true;
-}
 
 arduino::GSMClass GSM;

libraries/GSM/src/GSM.h

@@ -75,30 +75,37 @@ class GSMClass : public MbedSocketClass {
       }
     }
 
-  /* Start GSM connection.
-     * Configure the credentials into the device.
-     *
-     * param pin: Pointer to the pin string.
-     * param apn: Pointer to the apn string.
-     * param username: Pointer to the username string.
-     * param password: Pointer to the password string.
-     * param rat: Radio Access Technology.
-     * 
-     * return: 0 in case of success, negative number in case of failure
-     */
+  /*
+   * Start GSM connection. Configure the credentials into the device.
+   *
+   * param pin: Pointer to the pin string.
+   * param apn: Pointer to the apn string.
+   * param username: Pointer to the username string.
+   * param password: Pointer to the password string.
+   * param rat: Radio Access Technology.
+   *
+   * return: 0 in case of success, negative number in case of failure
+   */
   int begin(const char* pin, const char* apn, const char* username, const char* password, RadioAccessTechnologyType rat = CATNB, uint32_t band = BAND_20, bool restart = true);
 
   /*
-     * Disconnect from the network
-     *
-     * return: one value of wl_status_t enum
-     */
+   * Disconnect from the network
+   *
+   * return: one value of wl_status_t enum
+   */
   int disconnect(void);
 
+  /*
+   * Reset internal state machine in order to be ready to reconnect again.
+   */
   void end(void);
 
-  unsigned long getTime();
+  /*
+   * Change cellular state timeouts. Needs to be called before GSM.begin()
+   */
+  void setTimeout(unsigned long timeout);
 
+  unsigned long getTime();
   unsigned long getLocalTime();
 
   bool setTime(unsigned long const epoch, int const timezone = 0);
@@ -130,11 +137,12 @@ class GSMClass : public MbedSocketClass {
   mbed::CellularContext* _context = nullptr;
   mbed::CellularDevice* _device = nullptr;
   bool _at_debug = false;
+  unsigned long _timeout = 1000;
 
   /* Internal cellular state machine retries. Values are in seconds.
-   * This array also defines the maximum number of retries to 6
+   * This array also defines the maximum number of retries to CELLULAR_RETRY_ARRAY_SIZE
    */
-  const uint16_t _retry_timeout[6] = {1, 2, 4, 8, 16, 32};
+  const uint16_t _retry_timeout[CELLULAR_RETRY_ARRAY_SIZE] = {1, 2, 4, 8, 8, 8, 8, 8, 8, 8};
 
   static constexpr int RSSI_UNKNOWN = 99;
   static const char * const sim_state_str[];
@@ -150,7 +158,7 @@ class GSMClass : public MbedSocketClass {
   void onStatusChange(nsapi_event_t ev, intptr_t in);
 
   void reset();
-  bool isReady(const int timeout = 5000);
+  void on();
 };
 
 }

libraries/SocketWrapper/src/MbedClient.cpp

@@ -210,7 +210,10 @@ size_t arduino::MbedClient::write(const uint8_t *buf, size_t size) {
     return 0;
 
   sock->set_timeout(_timeout);
-  int ret = sock->send(buf, size);
+  int ret = NSAPI_ERROR_WOULD_BLOCK;
+  do {
+    ret = sock->send(buf, size);
+  } while ((ret != size && ret == NSAPI_ERROR_WOULD_BLOCK) && connected());
   sock->set_blocking(false);
   return ret >= 0 ? ret : 0;
 }