I hope, there’s someone with a Kling Garage door, who can say more. I don’t know either the Kling device nor tuya-only devices.
What I do in situations like this:
- is there a binding? - no in this case
- is there an open API?
- is there anything outside of openHAB, which speaks to this device?
- try to analyze the traffic, if there’s something you can connect to
ad 1)
no - as you said
ad 2)
ask the vendor, if there’s a possibility to use the API, the App does
perhaps this is still possible? it’s 4 years ago and I’m not sure, if tuya changed something since:
ad 3)
try searching for the specific device name on github, home assistant, iobroker, FHEM, … if there’s someone wo done it before. Then you can either use this as blueprint for your own script or use the piece of software within openHAB (e.g. using another smarthome software and utilize their API/MQTT/…
ad 4)
if you’re more an expert than I am, you can analyze the traffic coming from your device and/or App and try to see, if it uses some kind of API they use and if it is possible to use that within openHAB or a script in a scripting language of your choice.
=> if all of this fails I don’t think flashing the ESP in your device helps. But can you use another controller? is there a keypad on the outside using some kind of wireless protocol, which you can use? are there switches for up/down, you can utilize for a “dumb device - smarthome” situation? like adding some Wifi/zigbee switches to simulate pressing the switch?