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diff --git a/src/libcamera/base/event_dispatcher.cpp b/src/libcamera/base/event_dispatcher.cpp
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+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * event_dispatcher.cpp - Event dispatcher
+ */
+
+#include <libcamera/base/event_dispatcher.h>
+#include <libcamera/base/log.h>
+
+/**
+ * \file base/event_dispatcher.h
+ */
+
+namespace libcamera {
+
+LOG_DEFINE_CATEGORY(Event)
+
+/**
+ * \class EventDispatcher
+ * \brief Interface to manage the libcamera events and timers
+ *
+ * The EventDispatcher class allows the integration of the application event
+ * loop with libcamera by abstracting how events and timers are managed and
+ * processed.
+ *
+ * To listen to events, libcamera creates EventNotifier instances and registers
+ * them with the dispatcher with registerEventNotifier(). The event notifier
+ * \ref EventNotifier::activated signal is then emitted by the dispatcher
+ * whenever the event is detected.
+ *
+ * To set timers, libcamera creates Timer instances and registers them with the
+ * dispatcher with registerTimer(). The timer \ref Timer::timeout signal is then
+ * emitted by the dispatcher when the timer times out.
+ */
+
+EventDispatcher::~EventDispatcher()
+{
+}
+
+/**
+ * \fn EventDispatcher::registerEventNotifier()
+ * \brief Register an event notifier
+ * \param[in] notifier The event notifier to register
+ *
+ * Once the \a notifier is registered with the dispatcher, the dispatcher will
+ * emit the notifier \ref EventNotifier::activated signal whenever a
+ * corresponding event is detected on the notifier's file descriptor. The event
+ * is monitored until the notifier is unregistered with
+ * unregisterEventNotifier().
+ *
+ * Registering multiple notifiers for the same file descriptor and event type is
+ * not allowed and results in undefined behaviour.
+ */
+
+/**
+ * \fn EventDispatcher::unregisterEventNotifier()
+ * \brief Unregister an event notifier
+ * \param[in] notifier The event notifier to unregister
+ *
+ * After this function returns the \a notifier is guaranteed not to emit the
+ * \ref EventNotifier::activated signal.
+ *
+ * If the notifier isn't registered, this function performs no operation.
+ */
+
+/**
+ * \fn EventDispatcher::registerTimer()
+ * \brief Register a timer
+ * \param[in] timer The timer to register
+ *
+ * Once the \a timer is registered with the dispatcher, the dispatcher will emit
+ * the timer \ref Timer::timeout signal when the timer times out. The timer can
+ * be unregistered with unregisterTimer() before it times out, in which case the
+ * signal will not be emitted.
+ *
+ * When the \a timer times out, it is automatically unregistered by the
+ * dispatcher and can be registered back as early as from the \ref Timer::timeout
+ * signal handlers.
+ *
+ * Registering the same timer multiple times is not allowed and results in
+ * undefined behaviour.
+ */
+
+/**
+ * \fn EventDispatcher::unregisterTimer()
+ * \brief Unregister a timer
+ * \param[in] timer The timer to unregister
+ *
+ * After this function returns the \a timer is guaranteed not to emit the
+ * \ref Timer::timeout signal.
+ *
+ * If the timer isn't registered, this function performs no operation.
+ */
+
+/**
+ * \fn EventDispatcher::processEvents()
+ * \brief Wait for and process pending events
+ *
+ * This function processes all pending events associated with registered event
+ * notifiers and timers and signals the corresponding EventNotifier and Timer
+ * objects. If no events are pending, it waits for the first event and processes
+ * it before returning.
+ */
+
+/**
+ * \fn EventDispatcher::interrupt()
+ * \brief Interrupt any running processEvents() call as soon as possible
+ *
+ * Calling this function interrupts any blocking processEvents() call in
+ * progress. The processEvents() function will return as soon as possible,
+ * after processing pending timers and events. If processEvents() isn't in
+ * progress, it will be interrupted immediately the next time it gets called.
+ */
+
+} /* namespace libcamera */