RC Switch and Button support and refactor

[junwoo091400]

Describe problem solved by the proposed feature
Currently, PX4 doesn't support the following setup :

• Having one channel in RC configured for flight mode selection (e.g. Low : Position / High : Follow Me mode)
• Having an RTL button for activating Return To Launch by just pressing on the button once.

As the PX4 only considers 'Switches' (where you need to keep the RC signal state fixed, opposed to buttons which only changes signal momentarily), it's impossible to have the Button setup. Meaning, I need to be keep on pressing the RTL button for the RTL to stay activated throughout the RTL maneuver.

Describe your preferred solution
A clear and concise description of what you want to happen.

Describe possible alternatives
A clear and concise description of alternative solutions or features you've considered.

Additional context
Testing on the Mantis drone RC controller. Which has RTL button on lower-left and Flight mode button on lower-right.

FYI @dagar @MaEtUgR

[benjinne]

So buttons do work in some cases if you can configure your controller appropriately. For example with the radiomaster tx16 the buttons aren't momentary and instead latch and light up once the button is selected. That way it sort of acts like a switch. Since it seems like you can't configure your controller, I suggest looking at how the kill-switch works since it executes a permanent action on a momentary pulse.

[junwoo091400]

Thanks for your input! Yes I will check how that works :)

[junwoo091400]

Initial support and Unit tests being added here by @MaEtUgR : https://github.com/PX4/PX4-Autopilot/tree/rc-mode-switch-and-button

[junwoo091400]

/bounty $0

[junwoo091400]

/bounty $0.1

[junwoo091400]

/bounty $1

[algora-pbc]

💎 $1 bounty created by junwoo091400
🙋 If you start working on this, comment /attempt #19341 to notify everyone
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Attempt	Started (GMT+0)	Solution
🟢 @junwoo091400		#19638

[algora-pbc]

💡 @junwoo091400 submitted a pull request that claims the bounty. You can visit your bounty board to reward.

[DronecodeBot]

This issue has been mentioned on Discussion Forum for PX4, Pixhawk, QGroundControl, MAVSDK, MAVLink. There might be relevant details there:

https://discuss.px4.io/t/px4-maintainers-call-november-07-2023/35031/1