Add documentation

include/sta/atomic/mutex.hpp

@@ -1,3 +1,8 @@
+/**
+ * @brief Atomic mutex implementation.
+ *
+ * Define **STA_ATOMIC_ENABLE** to enable module.
+ */
 #ifndef STA_ATOMIC_MUTEX_HPP
 #define STA_ATOMIC_MUTEX_HPP
 
@@ -11,6 +16,9 @@
 
 namespace sta
 {
+	/**
+	 * @brief Implementation of `Mutex` interface using `std::atomic_flag`.
+	 */
 	class AtomicMutex : public Mutex
 	{
 	public:
@@ -20,7 +28,7 @@ namespace sta
 		void release() override;
 
 	private:
-		std::atomic_flag lock_;
+		std::atomic_flag lock_; /**< Atomic flag used as lock */
 	};
 } // namespace sta