Mbed OS Reference | CellularDevice.h Source File

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 /*
  * Copyright (c) 2017, Arm Limited and affiliates.
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 
 #ifndef CELLULAR_DEVICE_H_
 #define CELLULAR_DEVICE_H_
 
 #include "CellularStateMachine.h"
 #include "Callback.h"
 #include "ATHandler.h"
 #if (DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY)
 #include "UARTSerial.h"
 #endif // #if DEVICE_SERIAL
 
 /** @file CellularDevice.h
  * @brief Class CellularDevice
  *
  */
 namespace mbed {
 
 class CellularSMS;
 class CellularInformation;
 class CellularNetwork;
 class CellularContext;
 class FileHandle;
 
 const int MAX_PIN_SIZE = 8;
 const int MAX_PLMN_SIZE = 16;
 const int MAX_SIM_READY_WAITING_TIME = 30;
 
 /**
  * @addtogroup cellular
  * @{
  */
 
 /**
  *  Class CellularDevice
  *
  *  An abstract interface that defines opening and closing of cellular interfaces.
  *  You can delete or close opened interfaces only through this class.
  */
 class CellularDevice {
 public:
     /* enumeration for possible SIM states */
     enum SimState {
         SimStateReady = 0,
         SimStatePinNeeded,
         SimStatePukNeeded,
         SimStateUnknown
     };
 
     /** Returns singleton instance of CellularDevice, if Mbed target board has a supported
      *  onboard modem, or provide-default is defined for a cellular driver in JSON configuration
      *  files. Otherwise returns NULL. See NetworkInterface::get_default_instance for details.
      *
      *  @remark Application may override this (non-weak) default implementation.
      *
      *  @return default CellularDevice, NULL if not defined
      */
     static CellularDevice *get_default_instance();
 
     /** Return target onboard instance of CellularDevice
      *
      *  @remark Mbed OS target shall override (non-weak) this function for an onboard modem.
      *
      *  @return CellularDevice* instance, NULL if not defined
      */
     static CellularDevice *get_target_default_instance();
 
     /** Default constructor
      *
      *  @param fh   File handle used in communication with the modem.
      */
     CellularDevice(FileHandle *fh);
 
     /** virtual Destructor
      */
     virtual ~CellularDevice();
 
     /** Clear modem to a default initial state
      *
      *  Clear persistent user data from the modem, such as PDP contexts.
      *
      *  @pre All open network services on modem, such as contexts and sockets, must be closed.
      *  @post Modem power off/on may be needed to clear modem's runtime state.
      *  @remark CellularStateMachine calls this on connect when `cellular.clear-on-connect: true`.
      *
      *  @return         NSAPI_ERROR_OK on success, otherwise modem may be need power cycling
      */
     virtual nsapi_error_t clear();
 
     /** Sets the modem up for powering on
      *  This is equivalent to plugging in the device, i.e., attaching power and serial port.
      *  In general, hard_power_on and soft_power_on provides a simple hardware abstraction layer
      *  on top of the modem drivers written for Mbed OS; they can be overridden
      *  in a derived class to perform custom power controls in a particular board configuration.
      *  In many boards this will be a no-op if there is no separate power supply control circuitry.
      *
      *  @remark CellularStateMachine calls hard_power_on at first until successful,
      *  then soft_power_on and init until the modem responds.
      *  If you are not using CellularStateMachine then you need to call these functions yourself.
      *
      *  @post You must call soft_power_on to power on the modem after calling hard_power_on.
      *
      *  @return         NSAPI_ERROR_OK on success
      */
     virtual nsapi_error_t hard_power_on() = 0;
 
     /** Sets the modem in unplugged state
      *
      *  This is equivalent to pulling the plug off of the device, i.e.,
      *  detaching power and serial port.
      *
      *  This puts the modem in the lowest power state.
      *
      *  @remark CellularStateMachine disconnect or destruct does not shutdown or power off the modem,
      *  but you need to do that yourself.
      *
      *  @pre You must call soft_power_off to power off the modem before calling hard_power_off.
      *
      *  @return         NSAPI_ERROR_OK on success
      */
     virtual nsapi_error_t hard_power_off() = 0;
 
     /** Powers up the modem
      *
      *  This is equivalent to pressing the "power button" to activate or reset the modem
      *  and usually implemented as a short pulse on a dedicated GPIO signal.
      *  It is expected to be present to make it possible to reset the modem.
      *  The driver may repeat this if the modem is not responsive to AT commands.
      *
      *  @remark CellularStateMachine calls this when requested to connect.
      *  If you are not using CellularStateMachine then you need to call this function yourself.
      *
      *  @post You must call init to setup the modem.
      *
      *  @return         NSAPI_ERROR_OK on success
      */
     virtual nsapi_error_t soft_power_on() = 0;
 
     /** Powers down the modem
      *
      *  This is equivalent to turning off the modem by button press.
      *
      *  @remark CellularStateMachine disconnect or destruct does not shutdown or power off the modem,
      *  but you need to do that yourself.
      *
      *  @pre You must call shutdown to prepare the modem for power off.
      *
      *  @return         NSAPI_ERROR_OK on success
      */
     virtual nsapi_error_t soft_power_off() = 0;
 
     /** Open the SIM card by setting the pin code for SIM.
      *
      *  @param sim_pin  PIN for the SIM card
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_PARAMETER if sim_pin is null and sim is not ready
      *                  NSAPI_ERROR_DEVICE_ERROR on failure
      */
     virtual nsapi_error_t set_pin(const char *sim_pin) = 0;
 
     /** Get SIM card's state
      *
      *  @param state    current state of SIM
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_DEVICE_ERROR on failure
      */
     virtual nsapi_error_t get_sim_state(SimState &state) = 0;
 
     /** Creates a new CellularContext interface.
      *
      *  @param fh       file handle used in communication to modem. This can be, for example, UART handle. If null, then the default
      *                  file handle is used.
      *  @param apn      access point to use with context, can be null.
      *  @param cp_req       flag indicating if EPS control plane optimization is required
      *  @param nonip_req    flag indicating if this context is required to be Non-IP
      *
      *  @return         new instance of class CellularContext or NULL in case of failure
      *
      */
     virtual CellularContext *create_context(FileHandle *fh = NULL, const char *apn = NULL, bool cp_req = false, bool nonip_req = false) = 0;
 
 #if (DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY)
     /** Creates a new CellularContext interface. This API should be used if serial is UART and PPP mode used.
      *  CellularContext created will use data carrier detect to be able to detect disconnection much faster in PPP mode.
      *  UARTSerial usually is the same which was given for the CellularDevice.
      *
      *  @param serial       UARTSerial used in communication to modem. If null then the default file handle is used.
      *  @param apn          access point to use with context, can be null.
      *  @param dcd_pin      Pin used to set data carrier detect on/off for the given UART
      *  @param active_high  a boolean set to true if DCD polarity is active low
      *  @param cp_req       Flag indicating if EPS control plane optimization is required
      *  @param nonip_req    Flag indicating if this context is required to be Non-IP
      *
      *  @return         new instance of class CellularContext or NULL in case of failure
      *
      */
     virtual CellularContext *create_context(UARTSerial *serial, const char *apn, PinName dcd_pin = NC,
                                             bool active_high = false, bool cp_req = false, bool nonip_req = false) = 0;
 #endif // #if DEVICE_SERIAL
 
     /** Deletes the given CellularContext instance
      *
      *  @param context CellularContext to delete
      */
     virtual void delete_context(CellularContext *context) = 0;
 
     /** Stop the current operation. Operations: set_device_ready, set_sim_ready, register_to_network, attach_to_network
      *
      */
     void stop();
 
     /** Get the current FileHandle item used when communicating with the modem.
      *
      *  @return reference to FileHandle
      */
     FileHandle &get_file_handle() const;
 
     /** Get event queue that can be chained to main event queue.
      *  @return event queue
      */
     virtual events::EventQueue *get_queue();
 
     /** Set the pin code for SIM card
      *
      *  @param sim_pin      PIN for the SIM card
      */
     void set_sim_pin(const char *sim_pin);
 
     /** Plmn to use when registering to cellular network.
      *  If plmn is set, then registering is forced to this plmn. If plmn is not set, then automatic
      *  registering is used when registering to a cellular network. It doesn't start any operations.
      *
      *  @param plmn     plmn used when registering to cellular network
      */
     void set_plmn(const char *plmn);
 
     /** Start the interface
      *
      *  Initializes the modem for communication.
      *  API is asynchronous. Application can get results from CellularContext callback, which is set
      *  with attach(...), or callback, which is set by attach(...), in this class.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_NO_MEMORY on case of memory failure
      */
     nsapi_error_t set_device_ready();
 
     /** Start the interface
      *
      *  Attempts to open the sim.
      *  API is asynchronous. Application can get results from CellularContext callback, which is set
      *  with attach(...), or callback, which is set by attach(...), in this class.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_NO_MEMORY on case of memory failure
      */
     nsapi_error_t set_sim_ready();
 
     /** Start the interface
      *
      *  Attempts to register the device to cellular network.
      *  API is asynchronous. Application can get results from CellularContext callback, which is set
      *  with attach(...), or callback, which is set by attach(...), in this class.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_NO_MEMORY on case of memory failure
      */
     nsapi_error_t register_to_network();
 
     /** Start the interface
      *
      *  Attempts to attach the device to cellular network.
      *  API is asynchronous. Application can get results from CellularContext callback, which is set
      *  with attach(...), or callback, which is set by attach(...), in this class.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_NO_MEMORY on case of memory failure
      */
     nsapi_error_t attach_to_network();
 
     /** Register callback for status reporting.
      *
      *  The specified status callback function will be called on the network and cellular device status changes.
      *  The parameters on the callback are the event type and event-type dependent reason parameter.
      *
      *  @remark  deleting CellularDevice/CellularContext in callback not allowed.
      *  @remark  Allocating/adding lots of traces not recommended as callback is called mostly from State machines thread which
      *           is now 2048. You can change to main thread for example via EventQueue.
      *
      *  @param status_cb The callback for status changes.
      */
     void attach(Callback<void(nsapi_event_t, intptr_t)> status_cb);
 
     /** Create new CellularNetwork interface.
      *
      *  @param fh    file handle used in communication to modem. This can be, for example, UART handle. If null, then the default
      *               file handle is used.
      *  @return      New instance of interface CellularNetwork.
      */
     virtual CellularNetwork *open_network(FileHandle *fh = NULL) = 0;
 
     /** Create new CellularSMS interface.
      *
      *  @param fh    file handle used in communication to modem. This can be, for example, UART handle. If null, then the default
      *               file handle is used.
      *  @return      New instance of interface CellularSMS.
      */
     virtual CellularSMS *open_sms(FileHandle *fh = NULL) = 0;
 
     /** Create new CellularInformation interface.
      *
      *  @param fh    file handle used in communication to modem. This can be, for example, UART handle. If null, then the default
      *               file handle is used.
      *  @return      New instance of interface CellularInformation.
      */
     virtual CellularInformation *open_information(FileHandle *fh = NULL) = 0;
 
     /** Closes the opened CellularNetwork by deleting the CellularNetwork instance.
      */
     virtual void close_network() = 0;
 
     /** Closes the opened CellularSMS by deleting the CellularSMS instance.
      */
     virtual void close_sms() = 0;
 
     /** Closes the opened CellularInformation by deleting the CellularInformation instance.
      */
     virtual void close_information() = 0;
 
     /** Set the default response timeout.
      *
      *  @remark CellularStateMachine timeouts for all states are also changed to `timeout`.
      *
      *  @param timeout    milliseconds to wait response from modem
      */
     virtual void set_timeout(int timeout) = 0;
 
     /** Set an array of timeouts to wait before CellularStateMachine retries after failure.
      *  To disable retry behavior completely use `set_retry_timeout_array(NULL, 0)`.
      *  CellularContext callback event `cell_callback_data_t.final_try` indicates true when all retries have failed.
      *
      *  @remark Use `set_retry_timeout_array` for CellularStateMachine to wait before it retries again after failure,
      *          this is useful to send repetitive requests when don't know exactly when modem is ready to accept requests.
      *          Use `set_timeout` for timeout how long to wait for a response from modem for each request,
      *          this is useful if modem can accept requests but processing takes long time before sending response.
      *
      *  @param timeout      timeout array using seconds
      *  @param array_len    length of the array
      */
     void set_retry_timeout_array(const uint16_t timeout[], int array_len);
 
     /** Turn modem debug traces on
      *
      *  @param on         set true to enable debug traces
      */
     virtual void modem_debug_on(bool on) = 0;
 
     /** Initialize cellular device must be called right after the module is ready.
      *
      *  For example, when multiple cellular modules are supported in a single driver this function
      *  detects and adapts to an actual module at runtime.
      *
      *  @remark CellularStateMachine calls soft_power_on and init repeatedly when starting to connect
      *  until the modem responds.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_NO_MEMORY on case of memory failure
      *                  NSAPI_ERROR_UNSUPPORTED if current cellular module type is not detected
      *                  NSAPI_ERROR_DEVICE_ERROR if model information could not be read
      *
      */
     virtual nsapi_error_t init() = 0;
 
     /** Shutdown cellular device to minimum functionality.
      *
      *  Actual functionality is modem specific, for example UART may is not be responsive without
      *  explicit wakeup signal (such as RTS) after shutdown.
      *
      *  @remark You must call shutdown before power off to prepare the modem and to quit cellular network.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_DEVICE_ERROR on failure
      */
     virtual nsapi_error_t shutdown();
 
     /** Check whether the device is ready to accept commands.
      *
      *  @return         NSAPI_ERROR_OK on success
      *                  NSAPI_ERROR_DEVICE_ERROR on failure
      */
     virtual nsapi_error_t is_ready() = 0;
 
     /** Set callback function to listen when device is ready.
      *
      *  @param callback function to call on device ready, or NULL to remove callback.
      */
     virtual void set_ready_cb(Callback<void()> callback) = 0;
 
     /** Set power save mode
      *
      *  @remark See 3GPP TS 27.007 PSM for details
      *
      *  @param periodic_time    in seconds to enable power save, or zero to disable
      *  @param active_time      in seconds to wait before entering power save mode
      *
      *  @return              NSAPI_ERROR_OK on success
      *                       NSAPI_ERROR_DEVICE_ERROR on failure
      */
     virtual nsapi_error_t set_power_save_mode(int periodic_time, int active_time = 0) = 0;
 
     /** Get the linked list of CellularContext instances
      *
      *  @return Pointer to first item in linked list
      */
     virtual CellularContext *get_context_list() const;
 
     /** Get the current ATHandler instance in use for debug purposes etc.
      *  Once use has been finished call to release_at_handler() has to be made
      *
      *  @return Pointer to the ATHandler in use
      */
     virtual ATHandler *get_at_handler() = 0;
 
     /** Release the ATHandler taken into use with get_at_handler()
      *
      *  @param at_handler
      *  @return NSAPI_ERROR_OK on success, NSAPI_ERROR_PARAMETER on failure
      */
     virtual nsapi_error_t release_at_handler(ATHandler *at_handler) = 0;
 
 protected:
     friend class AT_CellularNetwork;
     friend class AT_CellularContext;
     friend class CellularContext;
 
     /** Get the retry array from the CellularStateMachine. Array is used in retry logic.
      *  Array contains seconds and retry logic uses those second to wait before trying again.
      *
      *  @param timeout      timeout array containing seconds for retry logic. Must have space for
      *                      CELLULAR_RETRY_ARRAY_SIZE (defined in CellularCommon.h)
      *  @param array_len    length of the timeout array on return
      */
     void get_retry_timeout_array(uint16_t *timeout, int &array_len) const;
 
     /** Cellular callback to be attached to Network and CellularStateMachine classes.
      *  CellularContext calls this when in PPP mode to provide network changes.
      *  This method will broadcast to every interested classes:
      *  CellularContext (might be many) and CellularStateMachine if available.
      */
     virtual void cellular_callback(nsapi_event_t ev, intptr_t ptr, CellularContext *ctx = NULL);
     void stm_callback(nsapi_event_t ev, intptr_t ptr);
     int _network_ref_count;
     int _sms_ref_count;
     int _info_ref_count;
     FileHandle *_fh;
     events::EventQueue _queue;
     CellularStateMachine *_state_machine;
 private:
     nsapi_error_t start_state_machine(CellularStateMachine::CellularState target_state);
     nsapi_error_t create_state_machine();
 
     CellularNetwork *_nw;
     char _sim_pin[MAX_PIN_SIZE + 1];
     char _plmn[MAX_PLMN_SIZE + 1];
     PlatformMutex _mutex;
     Callback<void(nsapi_event_t, intptr_t)> _status_cb;
 };
 
 /**
  * @}
  */
 
 } // namespace mbed
 
 #endif // CELLULAR_DEVICE_H_
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