Cellular: Change 3GPP TS 27.007 NIDD to async

Add a missing license header.
Remove semaphores and add +CRTDCP to support async operation.
Fix delete context and disconnect to execute just once.
Add support for NONIP PPD type.
Change CellularNetwork::clear() to virtual so it can be overridden.

Author: Ari Parkkila

UNITTESTS/features/cellular/framework/AT/at_cellularcontext/unittest.cmake

@@ -24,6 +24,7 @@ set(unittest-test-sources
   stubs/AT_CellularDevice_stub.cpp
   stubs/AT_CellularStack_stub.cpp
   stubs/AT_CellularNetwork_stub.cpp
+  stubs/AT_ControlPlane_netif_stub.cpp
   stubs/CellularDevice_stub.cpp
   stubs/CellularStateMachine_stub.cpp
   stubs/equeue_stub.c

UNITTESTS/stubs/AT_CellularContext_stub.cpp

@@ -198,6 +198,10 @@ bool AT_CellularContext::get_context()
     return true;
 }
 
+const char* AT_CellularContext::get_nonip_context_type_str() {
+    return "Non-IP";
+}
+
 bool AT_CellularContext::set_new_context(int cid)
 {
     return true;

UNITTESTS/stubs/AT_ControlPlane_netif_stub.cpp

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2019, 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.
+ */
+
+#include "CellularUtil.h"
+#include "ThisThread.h"
+#include "AT_ControlPlane_netif.h"
+#include "CellularLog.h"
+
+using namespace mbed_cellular_util;
+
+namespace mbed {
+
+AT_ControlPlane_netif::AT_ControlPlane_netif(ATHandler &at, int cid) : AT_CellularBase(at),
+    _cid(cid), _cb(NULL), _data(NULL)
+{
+}
+
+AT_ControlPlane_netif::~AT_ControlPlane_netif()
+{}
+
+void AT_ControlPlane_netif::urc_cp_recv()
+{
+}
+
+nsapi_size_or_error_t AT_ControlPlane_netif::send(const void *cpdata, nsapi_size_t cpdata_length)
+{
+    return cpdata_length;
+}
+
+nsapi_size_or_error_t AT_ControlPlane_netif::recv(void *cpdata, nsapi_size_t cpdata_length)
+{
+    return cpdata_length;
+}
+
+void AT_ControlPlane_netif::attach(void (*callback)(void *), void *data)
+{
+}
+
+void AT_ControlPlane_netif::data_received()
+{
+}
+
+} //mbed namespace

UNITTESTS/target_h/myCellularContext.h

@@ -160,6 +160,10 @@ class myCellularContext : public CellularContext {
         return true;
     };
 
+    const char* get_nonip_context_type_str() {
+        return "Non-IP";
+    }
+
     bool set_new_context(int cid)
     {
         return true;

features/cellular/framework/AT/AT_CellularContext.cpp

@@ -19,6 +19,7 @@
 #include "AT_CellularContext.h"
 #include "AT_CellularNetwork.h"
 #include "AT_CellularStack.h"
+#include "AT_ControlPlane_netif.h"
 #include "AT_CellularDevice.h"
 #include "CellularLog.h"
 #if (DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY)
@@ -322,6 +323,9 @@ void AT_CellularContext::set_credentials(const char *apn, const char *uname, con
 // PDP Context handling
 void AT_CellularContext::delete_current_context()
 {
+    if (_cid <= 0) {
+        return;
+    }
     tr_info("Delete context %d", _cid);
     _at.clear_error();
 
@@ -426,13 +430,17 @@ bool AT_CellularContext::get_context()
     return true;
 }
 
+const char* AT_CellularContext::get_nonip_context_type_str() {
+    return "Non-IP";
+}
+
 bool AT_CellularContext::set_new_context(int cid)
 {
     char pdp_type_str[8 + 1] = {0};
     pdp_type_t pdp_type = IPV4_PDP_TYPE;
 
     if (_nonip_req && _cp_in_use && get_device()->get_property(AT_CellularDevice::PROPERTY_NON_IP_PDP_TYPE)) {
-        strncpy(pdp_type_str, "Non-IP", sizeof(pdp_type_str));
+        strncpy(pdp_type_str, get_nonip_context_type_str(), sizeof(pdp_type_str));
         pdp_type = NON_IP_PDP_TYPE;
     } else if (get_device()->get_property(AT_CellularDevice::PROPERTY_IPV4V6_PDP_TYPE) ||
                (get_device()->get_property(AT_CellularDevice::PROPERTY_IPV4_PDP_TYPE) &&
@@ -544,7 +552,7 @@ nsapi_error_t AT_CellularContext::find_and_activate_context()
     }
 
     // do check for stack to validate that we have support for stack
-    if (!get_stack()) {
+    if (!(_nonip_req && _cp_in_use) && !get_stack()) {
         _at.unlock();
         tr_error("No cellular stack!");
         return NSAPI_ERROR_UNSUPPORTED;
@@ -950,6 +958,7 @@ void AT_CellularContext::cellular_callback(nsapi_event_t ev, intptr_t ptr)
             _nw = _device->open_network(_fh);
         }
 
+#if MBED_CONF_CELLULAR_CONTROL_PLANE_OPT
         if (_cp_req && !_cp_in_use && (_cb_data.error == NSAPI_ERROR_OK) &&
                 (st == CellularSIMStatusChanged && data->status_data == CellularDevice::SimStateReady)) {
             if (setup_control_plane_opt() != NSAPI_ERROR_OK) {
@@ -958,6 +967,7 @@ void AT_CellularContext::cellular_callback(nsapi_event_t ev, intptr_t ptr)
                 tr_info("Control plane SETUP success!");
             }
         }
+#endif
 
         if (_is_blocking) {
             if (_cb_data.error != NSAPI_ERROR_OK) {
@@ -1032,8 +1042,10 @@ void AT_CellularContext::cellular_callback(nsapi_event_t ev, intptr_t ptr)
 
 ControlPlane_netif *AT_CellularContext::get_cp_netif()
 {
-    tr_error("No control plane interface available from base context!");
-    return NULL;
+    if (!_cp_netif) {
+        _cp_netif = new AT_ControlPlane_netif(_at, _cid);
+    }
+    return _cp_netif;
 }
 
 nsapi_error_t AT_CellularContext::setup_control_plane_opt()
@@ -1056,35 +1068,30 @@ nsapi_error_t AT_CellularContext::setup_control_plane_opt()
     ciot_opt_ret = _nw->set_ciot_optimization_config(mbed::CellularNetwork::CIOT_OPT_CONTROL_PLANE,
                                                      mbed::CellularNetwork::PREFERRED_UE_OPT_CONTROL_PLANE,
                                                      callback(this, &AT_CellularContext::ciot_opt_cb));
-
-    if (ciot_opt_ret != NSAPI_ERROR_OK) {
-        return ciot_opt_ret;
-    }
-
-    //wait for control plane opt call back to release semaphore
-    _cp_opt_semaphore.try_acquire_for(CP_OPT_NW_REPLY_TIMEOUT);
-
-    if (_cp_in_use) {
-        return NSAPI_ERROR_OK;
+    if (ciot_opt_ret == NSAPI_ERROR_OK) {
+        // assume network supports CIoT optimizations until ciot_opt_cb
+        _cp_in_use = true;
     }
-
-    return NSAPI_ERROR_DEVICE_ERROR;
+    return ciot_opt_ret;
 }
 
 void AT_CellularContext::ciot_opt_cb(mbed::CellularNetwork::CIoT_Supported_Opt  ciot_opt)
 {
     if (ciot_opt == mbed::CellularNetwork::CIOT_OPT_CONTROL_PLANE ||
             ciot_opt == mbed::CellularNetwork::CIOT_OPT_BOTH) {
         _cp_in_use = true;
+    } else {
+        _cp_in_use = false;
     }
-    _cp_opt_semaphore.release();
 }
 
 void AT_CellularContext::set_disconnect()
 {
     tr_debug("AT_CellularContext::set_disconnect()");
-    _is_connected = false;
-    _device->cellular_callback(NSAPI_EVENT_CONNECTION_STATUS_CHANGE, NSAPI_STATUS_DISCONNECTED, this);
+    if (_is_connected) {
+        _is_connected = false;
+        _device->cellular_callback(NSAPI_EVENT_CONNECTION_STATUS_CHANGE, NSAPI_STATUS_DISCONNECTED, this);
+    }
 }
 
 void AT_CellularContext::set_cid(int cid)

features/cellular/framework/AT/AT_CellularContext.h

@@ -107,6 +107,10 @@ class AT_CellularContext : public CellularContext {
     virtual bool get_context();
     AT_CellularDevice::CellularProperty pdp_type_t_to_cellular_property(pdp_type_t pdp_type);
     bool set_new_context(int cid);
+    /** Get string name for NIDD context type.
+     *  @return     NIDD context text, e.g. Non-IP or NONIP
+     */
+    virtual const char* get_nonip_context_type_str();
 private:
 #if NSAPI_PPP_AVAILABLE
     nsapi_error_t open_data_channel();

features/cellular/framework/AT/AT_CellularNetwork.cpp

@@ -367,7 +367,11 @@ nsapi_error_t AT_CellularNetwork::set_ciot_optimization_config(CIoT_Supported_Op
                                                                Callback<void(CIoT_Supported_Opt)> network_support_cb)
 {
     _ciotopt_network_support_cb = network_support_cb;
-    return _at.at_cmd_discard("+CCIOTOPT", "=1,", "%d%d", supported_opt, preferred_opt);
+    nsapi_error_t err = _at.at_cmd_discard("+CRTDCP", "=", "%d", 1);
+    if (!err) {
+        err = _at.at_cmd_discard("+CCIOTOPT", "=1,", "%d%d", supported_opt, preferred_opt);
+    }
+    return err;
 }
 
 void AT_CellularNetwork::urc_cciotopti()
@@ -682,7 +686,7 @@ nsapi_error_t AT_CellularNetwork::clear()
             }
             context = context->next;
         }
-#ifdef MBED_CONF_NSAPI_DEFAULT_CELLULAR_APN
+#if defined(MBED_CONF_NSAPI_DEFAULT_CELLULAR_APN) && !MBED_CONF_CELLULAR_CONTROL_PLANE_OPT
         char pdp_type_str[sizeof("IPV4V6")];
         if (_device.get_property(AT_CellularDevice::PROPERTY_IPV4V6_PDP_TYPE) ||
                 (_device.get_property(AT_CellularDevice::PROPERTY_IPV4_PDP_TYPE) && _device.get_property(AT_CellularDevice::PROPERTY_IPV6_PDP_TYPE))) {

features/cellular/framework/AT/AT_CellularNetwork.h

@@ -119,7 +119,7 @@ class AT_CellularNetwork : public CellularNetwork {
      *
      *  @return         NSAPI_ERROR_OK on success
      */
-    nsapi_error_t clear();
+    virtual nsapi_error_t clear();
 
 private:
     void urc_creg();

features/cellular/framework/AT/AT_ControlPlane_netif.cpp

@@ -1,10 +1,31 @@
-/*AT_ControlPlane_netif.cpp*/
+/*
+ * Copyright (c) 2019, 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.
+ */
+
+#include "CellularUtil.h"
+#include "ThisThread.h"
 #include "AT_ControlPlane_netif.h"
+#include "CellularLog.h"
+
+using namespace mbed_cellular_util;
 
 namespace mbed {
 
 AT_ControlPlane_netif::AT_ControlPlane_netif(ATHandler &at, int cid) :
-    _cid(cid), _cb(NULL), _data(NULL), _recv_len(0), _at(at)
+    _cid(cid), _cb(NULL), _data(NULL), _at(at)
 {
     _at.set_urc_handler("+CRTDCP:", mbed::Callback<void()>(this, &AT_ControlPlane_netif::urc_cp_recv));
 }
@@ -18,44 +39,58 @@ void AT_ControlPlane_netif::urc_cp_recv()
     _at.lock();
     int cid = _at.read_int();
     int cpdata_length = _at.read_int();
-    int read_len = _at.read_string(_recv_buffer, sizeof(_recv_buffer));
-
-    _at.unlock();
+    if (cpdata_length < 0) {
+        return;
+    }
+    uint8_t *cpdata = new uint8_t[cpdata_length];
+    ssize_t read_len = _at.read_hex_string((char *)cpdata, cpdata_length);
 
     // cid not expected to be different because: one context - one file handle
     // so this file handle cannot get urc from different context
     if (read_len > 0 && read_len == cpdata_length && cid == _cid) {
-        _recv_len = read_len;
+        packet_t *packet = _packet_list.add_new();
+        packet->data = cpdata;
+        packet->data_len = cpdata_length;
         data_received();
+    } else {
+        delete[] cpdata;
     }
+    _at.unlock();
 }
 
 nsapi_size_or_error_t AT_ControlPlane_netif::send(const void *cpdata, nsapi_size_t cpdata_length)
 {
-    //CSODCP
-    _at.lock();
+    if (cpdata_length > MAX_CP_DATA_RECV_LEN) {
+        return NSAPI_ERROR_PARAMETER;
+    }
 
-    nsapi_size_or_error_t err = _at.at_cmd_discard("+CSODCP", "=", "%d%d%b", _cid, cpdata_length, cpdata, cpdata_length);
+    _at.lock();
+    _at.cmd_start("AT+CSODCP=");
+    _at.write_int(_cid);
+    _at.write_int(cpdata_length);
+    _at.write_hex_string((char *)cpdata, cpdata_length);
+    _at.cmd_stop_read_resp();
+    nsapi_size_or_error_t err = _at.unlock_return_error();
 
-    return (err == NSAPI_ERROR_OK) ? cpdata_length : err;
+    return err ? err : cpdata_length;
 }
 
 nsapi_size_or_error_t AT_ControlPlane_netif::recv(void *cpdata, nsapi_size_t cpdata_length)
 {
-    // If no data received through CRTDCP URC
-    if (!_recv_len) {
-        return NSAPI_ERROR_WOULD_BLOCK;
-    }
-
-    // If too small buffer for data
-    if (_recv_len > cpdata_length) {
-        return NSAPI_ERROR_DEVICE_ERROR;
+    _at.lock();
+    if (_packet_list.count() <= 0) {
+       (void) send("", 0); // poll for missing +CRTDCP indications
+        if (_packet_list.count() <= 0) {
+            return NSAPI_ERROR_WOULD_BLOCK;
+        }
     }
-
-    memcpy(cpdata, _recv_buffer, _recv_len);
-    size_t recv = _recv_len;
-    _recv_len = 0;
-    return recv;
+    packet_t *packet = _packet_list.dequeue();
+    int data_len = (cpdata_length >= packet->data_len) ? packet->data_len : cpdata_length;
+    memcpy(cpdata, packet->data, data_len);
+    delete[] packet->data;
+    delete (packet);
+    _at.unlock();
+    return data_len;
 }
 
 void AT_ControlPlane_netif::attach(void (*callback)(void *), void *data)