How to define multiple hardware interfaces for ros2 control in the xacro

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I'm not sure how to define multiple hardware interfaces and assign the right joints. Does this work?

<ros2_control name="RealRobot" type="system">
   <hardware>
       <plugin>steering_hardware/SteeringHardware</plugin>
   </hardware>
   <joint name="steering_joint">
       <command_interface name="position"/>
       <state_interface name="velocity"/>
       <state_interface name="position"/>
   </joint>
   <hardware>
       <plugin>wing_hardware/WingHardware</plugin>
   </hardware>
   <joint name="wing_joint">
       <command_interface name="velocity"/>
       <state_interface name="velocity"/>
       <state_interface name="position"/>
   </joint>
</ros2_control>

I'm getting an error when launching the controller manager but I don't know if it's related to this, so I want to make sure this piece is correct at least.

Thanks