+ // Create a new card, mark it immediately as DEAD and hold it.
+ // Returns the new index.
+ unsigned create_dead_card(const std::string &name, const std::string &info, unsigned num_channels);
+
+ // Make a protobuf representation of the given card, so that it can be
+ // matched against at a later stage. For AudioMixer only.
+ // The given card must be held.
+ void serialize_device(unsigned index, DeviceSpecProto *serialized);
+