Create Zephyr workspace app

include/app/lib/custom.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2021, Legrand North America, LLC.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef APP_LIB_CUSTOM_H_
+#define APP_LIB_CUSTOM_H_
+
+/**
+ * @defgroup lib_custom Custom library
+ * @ingroup lib
+ * @{
+ *
+ * @brief An example of a custom out-of-tree library.
+ *
+ * This library illustrates how create custom out-of-tree libraries. Splitting
+ * code in libraries enables code reuse and modularity, also easing testing.
+ */
+
+/**
+ * @brief Return @p val if non-zero, or Kconfig-controlled default.
+ *
+ * Function returns the provided value if non-zero, or a Kconfig-controlled
+ * default value if the parameter is zero. This trivial function is provided in
+ * order to have a library interface example that is trivial to test.
+ *
+ * @param val Value to return if non-zero
+ *
+ * @retval val if @p val is non-zero
+ * @retval CONFIG_CUSTOM_GET_VALUE_DEFAULT if @p val is zero
+ */
+int custom_get_value(int val);
+
+/** @} */
+
+#endif /* APP_LIB_CUSTOM_H_ */