I have good news: my G 29 is working well.Here is what I did, it may be useful to someone else later:
I bought a "USB HUB", powered (very important: "powered"), and I connected my steering wheel to it.
Indeed, I suspect my USB ports are defective, even if they work well with mouse, keyboard, etc.
I only have one problem left to solve: reverse gear !
I use the shifter, connected via a Leo Bodnar adapter, also plugged into the Hub.
So I can't use reverse gear. I don't know how to configure
I know that "pepe" will not fail to make me understand that reverse gear is useless, but I prefer to solve this problem quickly!
thank you everyone for your help and your contribution, it’s nice to see that the GPL community is alive and well!