Right after power-on:

# gphoto2 --camera "USB PTP Class Camera" --port usb: --list-config
/main/settings/owner
/main/settings/model
/main/settings/firmwareversion
/main/settings/time
/main/settings/beep
/main/settings/capturetarget
/main/settings/capture
/main/capturesettings/focuslock

After I have setup a remote capture:

# gphoto2 --camera "USB PTP Class Camera" --port usb: --list-config
/main/settings/owner
/main/settings/model
/main/settings/firmwareversion
/main/settings/time
/main/settings/beep
/main/settings/capturetarget
/main/settings/capture
/main/imgsettings/imgquality
/main/imgsettings/imgsize
/main/imgsettings/iso
/main/imgsettings/whitebalance
/main/imgsettings/photoeffect
/main/capturesettings/zoom
/main/capturesettings/assistlight
/main/capturesettings/exposurecompensation
/main/capturesettings/canonflashmode
/main/capturesettings/aperture
/main/capturesettings/focusingpoint
/main/capturesettings/shutterspeed
/main/capturesettings/meteringmode
/main/capturesettings/afdistance
/main/capturesettings/focuslock