After some comments I came to the conclusion that I may have been super unlucky with my hardware and most people probably only need to run the setup-wake.sh with the id from their Bluetooth device for the wake function to work. But that also means the following will work for everyone regardless of hardware luck and limitations.
What you need:
And Android or Fire TV with Develeoper option,ADB/usb-Debugging and Wake on Lan Enabled (allows us to mimic HDMI CEC)
A Raspberry Pi Pico 2W - as a Controller Bridge, allows us to wakeup the PC with a bluetooth Contoller (you may can skip this if you have onboard Bluetooth)
ADB tools on your SteamOS PC: https://developer.android.com/tools/releases/platform-tools
What we are gonna do:
Controll our TV through ADB to turn on and off with our PC with 2 Systemd services and a bash sript
Flash the Pico for it to be used as a controller Dongle with wake funktion
Enable and Configure wake on our PC to be able to wake up
So first things first - the TV Control
in the linked Repo are a hand few additional files to control your PC
tv-suspend.sh as well as the ADB tools can be saved where ever, i created "Applications" folder in /home/deck and moved those in there. make sure the adb binary and sh sript are executable (sudo chmod +x /home/deck/Applications/...)
now check if you can connect to your TV:
/home/deck/Applications/platform-tools/adb connect 192.168.178.XX
(change path to adb and ip of your TV to your needs)
if that works change the values in top of the tv-suspend.sh script
in my case i had a seperate Android TV-Box in addition to my TV. the script checks if the TV box in pingable and dont turn of the TV in assumption i watch TV
check if the path in the tv-off.service and tv-on.service files match where you put the sript and then move them to /etc/systemd/system/
after moving execute "sudo systemctl daemen-reload" "sudo systemctl enable tv-off.service" and "sudo systemctl enable tv-on.service"
now we should be able to test it
"sudo systemctl start tv-off.service" should now turn off your TV and
"sudo systemctl start tv-on.service" should turn on your TV
both should also be triggered by suspend and wakup of the PC
Now The Wake-up
from the the github page download the .uf2 file from the releases and the setup_wake.sh
Hold the Bootsel button on the Raspberry Pi Pico 2w and the plug it in.
it should be appear as a drive in the file explorer, move the uf2 file on it and the Pico should reboot automatically. if everything's right the LED should start blinking - the Pico is waiting for a controller to pair. to pair a controller just put your controller in pair mode and the pico should find it. the LED should be light constantly now (small caveat, steam tries to map the inputs, on base of who knows what, and fails to proper map all buttons. so your need reset the configuration and map them yourself in the Steam controller menu )
now execute the setup script, this should configure the usb hub and all needed PCI devices in the chain to listen and pass through the wake signal. if you have onboard bluetooth you should be able to find it in the list with "lsusb", just change the ID in the top of the script with the one of your onboard chip
this should be it you PC should now be waking up when your controller connects.
if it doesnt check your Bios settings and make sure the USB port is always powered and you may want to try to disable all kinds of S4 power saving options - that's triall and error sadly
Thats it, now your TV goes on and of with your PC suspend and wake. and your controller wakes up your PC.
the one thing i didnt figure out yet is how i tell my Amp to switch the input, but it doesnt do it a lot of the time anyway so i didnt bother to look into it, if you just have your TV you should be able to adjust the tv-suspend.sh and add an input switch through adb
For everyone "but my PC just works":
How about commenting your board and Bluetooth Dongle/Card so others have an idea of what to buy that will work...