The ps3controller and sixaxis are the ones you need to install, but not at the same time. Remove both and try with the sixaxis driver only - both for the PS3 and the clone (for which you might have to enable 3rd party clone support in the driver).
I don't think the dongle will help, the Bluetooth connection should be ok on the 3B+ model.
How did you install your RetroPie system ?
Thank you everyone, now it's "working" but I'm not sure why. I've started again from scratch with a fresh installation, and it's working fine out of the box, as @ChuckyP said. At least is working with the padtest iso, when I push on R3 it starts running the weak motor, and with L3 the strong one. I suppose that I messed up something while trying to install/uninstall packages and stuff.
However it's not working with Final Fantasy VIII. Vibration is enabled ingame, I've tried with several bios and two different copies from the game, without success. Anyway, if it's working with the padtest then it works, and based on other comments I suppose that this feature doesn't work for all the games, but I need to test it more.
NOTE: If you don't know how to test PRs, then it may be wise not to try testing this, as I'll need some basic technical competence to provide logs, etc., if something goes wrong.
sorry, but I've just read your note about how to test the driver and I fear that I can't help here.
I'm really not familiar with pull requests; and even for basic linux things I need to follow step by step instructions... not knowing what and why I'm typing things in more than 80% of cases.
I have several joysticks identified as DragonRise Inc. Generic USB Joystick (one of them is completely new). And joysticks identified as Personal Cummunication Systems, Inc. PlayStation Gamepad. None of them has vibration in PSX games (Vibration is enabled in RetroArch menu and in the game; type of the joystick were changed to analog). Should I install some drivers or what (just curious; I can't say, I really need that)?
For anyone who thinks they have an “official” controller and it doesnt work you probably have a bootleg controller. Black is the only color i personally have seen the bootlegs in but i have seen hundreds of them.
@TMNTturtlguy yup. But if i need a bulk set of games that use the same core options or same retroarch.cfg options, i have their individual configs pointing to a different core-options or retroarch.cfg file that i created. So for example psx games that use analog option, i would point their individual config to a different core-options config that i created just for psx that has the analog enabled. That way if the core options ever have any changes made, i dont have to change each config, just the one.