+static DECLARE_WORK(gameport_event_work, gameport_handle_events);
+
+static int gameport_queue_event(void *object, struct module *owner,
+ enum gameport_event_type event_type)
+{
+ unsigned long flags;
+ struct gameport_event *event;
+ int retval = 0;
+
+ spin_lock_irqsave(&gameport_event_lock, flags);
+
+ /*
+ * Scan event list for the other events for the same gameport port,
+ * starting with the most recent one. If event is the same we
+ * do not need add new one. If event is of different type we
+ * need to add this event and should not look further because
+ * we need to preserve sequence of distinct events.
+ */
+ list_for_each_entry_reverse(event, &gameport_event_list, node) {
+ if (event->object == object) {
+ if (event->type == event_type)
+ goto out;
+ break;
+ }
+ }
+
+ event = kmalloc(sizeof(struct gameport_event), GFP_ATOMIC);
+ if (!event) {
+ pr_err("Not enough memory to queue event %d\n", event_type);
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ if (!try_module_get(owner)) {
+ pr_warning("Can't get module reference, dropping event %d\n",
+ event_type);
+ kfree(event);
+ retval = -EINVAL;
+ goto out;
+ }
+
+ event->type = event_type;
+ event->object = object;
+ event->owner = owner;
+
+ list_add_tail(&event->node, &gameport_event_list);
+ schedule_work(&gameport_event_work);
+
+out:
+ spin_unlock_irqrestore(&gameport_event_lock, flags);
+ return retval;
+}
+