mbed LoRaWAN stack

Revision:
2:bbb1f6ce5970
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/trace_helper.cpp	Tue Jun 05 08:29:27 2018 +0000
@@ -0,0 +1,90 @@
+/**
+ * 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.
+ */
+
+#include "drivers/Serial.h"
+
+/**
+ * Serial object for console tracing
+ */
+mbed::Serial pc(USBTX, USBRX, MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE);
+
+/**
+ * If we have tracing library available, we can see traces from within the
+ * stack. The library could be made unavailable by removing FEATURE_COMMON_PAL
+ * from the mbed_app.json to save RAM.
+ */
+#if defined(FEATURE_COMMON_PAL)
+
+    #include "platform/PlatformMutex.h"
+    #include "mbed_trace.h"
+
+    /**
+     * Local mutex object for synchronization
+     */
+    static PlatformMutex mutex;
+
+    static void serial_lock();
+    static void serial_unlock();
+    static void trace_printer(const char* str);
+
+    /**
+     * Sets up trace for the application
+     * Wouldn't do anything if the FEATURE_COMMON_PAL is not added
+     * or if the trace is disabled using mbed_app.json
+     */
+    void setup_trace()
+    {
+        // setting up Mbed trace.
+        mbed_trace_mutex_wait_function_set(serial_lock);
+        mbed_trace_mutex_release_function_set(serial_unlock);
+        mbed_trace_init();
+        mbed_trace_print_function_set(trace_printer);
+    }
+
+    /**
+     * Lock provided for serial printing used by trace library
+     */
+    static void serial_lock()
+    {
+        mutex.lock();
+    }
+
+    /**
+     * Releasing lock provided for serial printing used by trace library
+     */
+    static void serial_unlock()
+    {
+        mutex.unlock();
+    }
+
+    /**
+     * Prints the Mbed trace, used by trace library.
+     * Not intended for local use.
+     */
+    static void trace_printer(const char* str)
+    {
+        pc.printf("%s\r\n", str);
+    }
+
+#else
+
+    void setup_trace()
+    {
+    }
+
+#endif
+