Controller input mapping works in Emulation Station but not in emulators

mcpat

root@rpizerosm:/opt/RetroPie-Setup# jstest /dev/input/js0
Driver version is 2.1.0.
Joystick (N64 Controller) has 4 axes (X, Y, Hat0X, Hat0Y)
and 13 buttons (BtnA, BtnB, BtnZ, BtnTL, BtnTR, BtnTR2, BtnStart, (null), (null), (null), (null), Btn0, Btn1).
Testing ... (interrupt to exit)
Axes:  0:     0  1: -2234  2:     0  3:     0 Buttons:  0:off  1:off  2:off  3:off  4:off  5:off  6:off  7:off  8:off  9:off 10:off 11:off 12:off

Buttons are:

0 = A
1 = B
2 = Z (Below in the middle)
3= TL
4 = TR
5 = ZR (right button on the back site)
6 = Start
7 = Yellow up
8 = Yellow down
9 = Yellow left
10 = Yellow right
11 = "Power" (right round button on the back site)
12 = "Square Button" on the left back site

mitu

@mcpat Looking at the jstest output, it seems to coincide with what ES input condfiguration recorded - A is 0, B is 1, X is 2, etc.
Now in Linux there are 2 APIs for joystick - a 'legacy' one and one based on evdev. jstest uses the 'legacy' API and enumerates the buttons starting from 0, while the evdev one seems to start with 2, though it still advertises BTN_0 and BTN_1.
SDL (which is used by ES for input processing/mapping) is supposed to use the evdev interface (but can fallback to the 'legacy' one) and so is RetroArch, but somehow the button numbering in SDL starts from 0 (?) instead of 2, as reported by evdev. I'm not sure whether it's a SDL bug (assuming buttons always start from 0) or maybe the Linux driver doesn't implement the 'legacy' joystick API (unlikely though).

mcpat

@mitu
thank you for the feedback.

So how can we/I solve the problem? I tried to patch in the meantime hid-nx, joycond, ... but no success. If you can give me a hint where to look (e.g. SDL, emulationstation, retroarch, ...) I can try to find the button numbering.

Thank you again!

mcpat

@mitu
Is it this line?

Really interested in patching ;)

mitu

@mcpat said in Controller input mapping works in Emulation Station but not in emulators:

Is it this line?

No, EmulationStation doesn't use the gamecontroller subsystem, but the joystick subsystem. Regardless, the gamecontroller mapping doesn't change the button numbering, it's just a mapping.

mcpat

@mitu
so how can I solve the problem to be able to use autoconfig?
Where can I force "legacy" for ES? Or how can I force to do the autoconfig with the numbering from evdev?
Now it's a pain to open a ssh connection and do the correction by hand.

Thank you for your patience!

mitu

Didn't you already corrected the configuration profile ? It should be enough, the profile is written only when you change the input configuration in EmulationStation, so it's not going to be changed unless you re-configure your controller(s).

mcpat

@mitu
yes it's solved by now, but I am interested in how to solve it for the future and what is causing this +2 shift. If you are not willing to further support, I fully unterstand. It's more my personal interest to find and solve the bug so others don't have this problems.
I was googling a while to find it out, even I am not a beginner (in linux).

mitu

@mcpat said in Controller input mapping works in Emulation Station but not in emulators:

If you are not willing to further support, I fully unterstand.

I would if I could :).

mcpat

@mitu
I solved the problem. It was in the source code of hid-nx....

see here. It was the BTN_0 and BTN_1

I modified the code like this for both controllers and they are now working correctly!

Can be found starting here

static const struct nx_con_button_mapping gencon_button_mappings[] = {
	{ BTN_SOUTH,	NX_CON_BTN_A,		},
	{ BTN_EAST,	NX_CON_BTN_B,		},
	{ BTN_WEST,	NX_CON_BTN_R,		},
	{ BTN_DPAD_LEFT,	NX_CON_BTN_X,		},
	{ BTN_DPAD_UP,		NX_CON_BTN_Y,		},
	{ BTN_DPAD_RIGHT,	NX_CON_BTN_L,		},
	{ BTN_THUMBL,	NX_CON_BTN_ZR,		},
	{ BTN_START,	NX_CON_BTN_PLUS,	},
	{ BTN_SELECT,	NX_CON_BTN_HOME,	},
	{ BTN_MODE,	NX_CON_BTN_CAP,		},
	{ /* sentinel */ },
};

/*
 * N64's C buttons get assigned to d-pad directions and registered as buttons.
 */
static const struct nx_con_button_mapping n64con_button_mappings[] = {
	{ BTN_A,		NX_CON_BTN_A,		},
	{ BTN_B,		NX_CON_BTN_B,		},
	{ BTN_Z,		NX_CON_BTN_ZL,		},
	{ BTN_TL,		NX_CON_BTN_L,		},
	{ BTN_TR,		NX_CON_BTN_R,		},
	{ BTN_TR2,		NX_CON_BTN_LSTICK,	},
	{ BTN_START,		NX_CON_BTN_PLUS,	},
	{ BTN_DPAD_UP,		NX_CON_BTN_Y,		},
	{ BTN_DPAD_DOWN,	NX_CON_BTN_ZR,		},
	{ BTN_DPAD_LEFT,	NX_CON_BTN_X,		},
	{ BTN_DPAD_RIGHT,	NX_CON_BTN_MINUS,	},
	{ BTN_THUMBL,		NX_CON_BTN_HOME,	},
	{ BTN_MODE,		NX_CON_BTN_CAP,		},
	{ /* sentinel */ },
};