Mayflash N64 Controller Adapter - Analog, C-buttons and d-pad not working/not responsive

[MGZero]

Summary

Using a Mayflash USB N64 controller adapter:
Analog stick, d-pad and c-buttons are not responsive while binding controller inputs. Other buttons work fine. Tried with several N64 controllers, as well as other emulators to rule out the adapter. Only able to reproduce in Bizhawk, regardless of N64 controller used.

Repro

1. Plug in a first party N64 controller via USB adapter
2. Attempt to set bindings for D-pad, C-buttons or analog stick.
   Expected behavior: Input is detected from the controller and bindings are set
   Actual behavior: No input detected, it's as if nothing is being pressed

Host system

Bizhawk 2.10 WIndows 10 Pro 22H2 AMD Ryzen 5600x
Mayflash adapter in question: https://www.amazon.com/dp/B002B9FIUU

[Morilli]

Could you check whether you get the same results in the latest dev build as well? This may have been fixed already.

[MGZero]

@Morilli Behaving a bit differently on the latest. C-buttons and D-pad still don't work, and the analog stick still does not work on the analog controls tab. However, the analog on the normal controls tab is registering as the D-pad

[CasualPokePlayer]

Does it use J1 or X1 here?

[MGZero]

@CasualPokePlayer X2

[CasualPokePlayer]

Seems this is a known issue in SDL: libsdl-org/SDL#6079

The problem with it is that its VID/PID collided with another controller, so you'd end up getting nonsensical results from an SDL_GameController. Newer (relatively speaking) SDL versions had changes done so mappings could be created regardless, although seems for that it needs to have mappings created using a program linked in that issue, which the OP apparently never did.

[CasualPokePlayer]

controllermap.zip
This would be the controller mapping program (built off latest SDL2 commit), could you try running this with that N64 adapter?

[MGZero]

@CasualPokePlayer That does detect the controller correctly, though the N64 controller doesn't have enough buttons to map it all to the xbox controller on screen haha. It does recognize all the inputs though!

[CasualPokePlayer]

What was the output given?