include/hw/virtio: document virtio_notify_config

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230710153522.3469097-5-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

include/hw/virtio/virtio.h

@@ -276,6 +276,13 @@ extern const VMStateInfo virtio_vmstate_info;
 
 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
 
+/**
+ * virtio_notify_config() - signal a change to device config
+ * @vdev: the virtio device
+ *
+ * Assuming the virtio device is up (VIRTIO_CONFIG_S_DRIVER_OK) this
+ * will trigger a guest interrupt and update the config version.
+ */
 void virtio_notify_config(VirtIODevice *vdev);
 
 bool virtio_queue_get_notification(VirtQueue *vq);