How to know if RC is timed out/disconnected, via mavlinlk telemetry?

Is there is a way to get a RC state via mavlink? I am using an ELRS receiver with matek f405 controlller, connected to raspberry. All the high-level functionality on my boat is implemented on the companion computer, and i want to implement RC filesafe on it, the way i need. But i didn`t find the right mavlink message, contains that information.