Merge pull request #6570 from jarvte/add_cellular_detach

Cellular: add detach from the network

Author: Cruz Monrreal

features/cellular/framework/API/CellularNetwork.h

@@ -272,9 +272,11 @@ class CellularNetwork : public NetworkInterface
 
     /** Request attach to network.
      *
+     *  @deprecated Parameter timeout will be deprecated. Use mbed-os/features/cellular/framework/API/CellularDevice.h set_timeout instead.
      *  @param timeout milliseconds to wait for attach response
      *  @return        zero on success
      */
+    MBED_DEPRECATED_SINCE("mbed-os-5.9", "Parameter timeout will be deprecated. Use mbed-os/features/cellular/framework/API/CellularDevice.h set_timeout instead.")
     virtual nsapi_error_t set_attach(int timeout = 10*1000) = 0;
 
     /** Request attach status from network.
@@ -284,6 +286,12 @@ class CellularNetwork : public NetworkInterface
      */
     virtual nsapi_error_t get_attach(AttachStatus &status) = 0;
 
+    /** Request detach from a network.
+     *
+     *  @return        zero on success
+     */
+    virtual nsapi_error_t detach() = 0;
+
     /** Get APN rate control.
      *
      *  @remark optional params are not updated if not received from network, so use good defaults

features/cellular/framework/AT/AT_CellularNetwork.cpp

@@ -753,7 +753,7 @@ bool AT_CellularNetwork::has_registration(RegistrationType reg_type)
     return true;
 }
 
-nsapi_error_t AT_CellularNetwork::set_attach(int timeout)
+nsapi_error_t AT_CellularNetwork::set_attach(int /*timeout*/)
 {
     _at.lock();
 
@@ -790,6 +790,19 @@ nsapi_error_t AT_CellularNetwork::get_attach(AttachStatus &status)
     return _at.unlock_return_error();
 }
 
+nsapi_error_t AT_CellularNetwork::detach()
+{
+    _at.lock();
+
+    tr_debug("Network detach");
+    _at.cmd_start("AT+CGATT=0");
+    _at.cmd_stop();
+    _at.resp_start();
+    _at.resp_stop();
+
+    return _at.unlock_return_error();
+}
+
 nsapi_error_t AT_CellularNetwork::get_apn_backoff_timer(int &backoff_timer)
 {
     // If apn is set

features/cellular/framework/AT/AT_CellularNetwork.h

@@ -74,6 +74,8 @@ class AT_CellularNetwork : public CellularNetwork, public AT_CellularBase
 
     virtual nsapi_error_t get_attach(AttachStatus &status);
 
+    virtual nsapi_error_t detach();
+
     virtual nsapi_error_t get_rate_control(CellularNetwork::RateControlExceptionReports &reports,
         CellularNetwork::RateControlUplinkTimeUnit &time_unit, int &uplink_rate);