diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index 0671989..631490b 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -219,6 +219,12 @@
 void virtio_instance_init_common(Object *proxy_obj, void *data,
                                  size_t vdev_size, const char *vdev_name);
 
+/**
+ * virtio_init() - initialise the common VirtIODevice structure
+ * @vdev: pointer to VirtIODevice
+ * @device_id: the VirtIO device ID (see virtio_ids.h)
+ * @config_size: size of the config space
+ */
 void virtio_init(VirtIODevice *vdev, uint16_t device_id, size_t config_size);
 
 void virtio_cleanup(VirtIODevice *vdev);