I’ve did all this, and the relevant lines in the libretto.cfg afterwards seem to be:
input_device_p1 = “0”
input_player1_joypad_index = “0”
input_libretro_device_p1 = “5”
input_player1_analog_dpad_mode = “0”
When searching for it in the retroarch.cfg it’s even documented:
# Sets which libretro device is used for a user.
# Devices are indentified with a number.
# This is normally saved by the menu.
# Device IDs are found in libretro.h.
# These settings are overridden by explicit command-line arguments which refer to input devices.
# None: 0
# Joypad (RetroPad): 1
# Mouse: 2
# Keyboard: 3
# Generic Lightgun: 4
# Joypad w/ Analog (RetroPad + Analog sticks): 5
# Multitap (SNES specific): 257
# Super Scope (SNES specific): 260
# Justifier (SNES specific): 516
# Justifiers (SNES specific): 772
BUT: When starting up, screen says
RetroArch [WARN] :: Input device ID 5 is unknown to this libretro implementation. Using RETRO_DEVICE_JOYPAD.
And it’s behaves like an all analog controller (with the known errors in certain games).
So, i guess it’s the correct way (THX!), but since retroarch claims to not know the device id, it’s a bug…