OMG! I'm so dumb!
I've just discovered that you can change the PS3 controller driver in /recalbox/share/system/recalbox.conf.
I switched from bluez to official and now the controller turns off after 30 minutes inactivity
And as a positive side effect: Control within kodi now works with 2 same controllers
But to get PS3 controllers working via bluetooth wirelessly with official drivers, you have to pair them at least once with bluez drivers activated before.
If you first switch to official drivers without pairing controllers before with bluez, you can not get them to work without usb-cable connected.
And there are several disadvantages that result from switching to official:
- the 4 LEDs on the controller are constantly flashing (with bluez driver on Controller/Player 1 only first LED is permanently on), but it can be fixed by just starting a PSX game (hmm, strange)
- you can not see the battery status of the controller in System Settings, Information anymore
- problems in dreamcast emulators with official drivers:
Reicast - Reicast (which is default)
left analog stick reacts strange... when pushing left analog stick hard to left it goes to right and when you push hard up, it goes to down. If you just push the analog carefully for about 50% it works as it should (up is up and left is left), but if you push 100% to left or up it goes to right respectively down)
It is the exact same problem, as this user here had with recalbox: https://forum.recalbox.com/topic/15290/dreamcast-ps3-controller-issue.
But according to the answer of the user Substring, it seems that it is a known reicast problem and does not occur with bluez drivers (the answers in this post from my side can be ignored, i was confused and have mixed up something)
Libretro - Reicast
rumble behaves strange in some games (like Crazy Taxi for example, it rumbles almost all the time. Strangely it does not rumble, when crashing against walls or into other cars. Because of all that rumble the battery of the controller quickly drains to zero and controller turns off after short time
and i could not find the option in RetroArch Menu to disable rumble)
With bluez drivers you do not have those problems in Dreamcast emulators.
I also tested with shanwan drivers, and it behaves exactly the same as with official drivers.