Is it possible to use the FnLock/Esc LED on Thinkpad T580 as a layout switch indicator using XKB? At the moment I use CapsLock as an indicator and AltGr as a toggle key, but since capslock LED is located right on capslock key, it's usually hidden by the hand.

 setxkbmap -layout us,ru -option "grp:toggle,ctrl:nocaps,grp_led:caps,compose:prsc,terminate:ctrl_alt_bksp"

As for FnLock, I can't find this led in /sys/class/leds:

 $ ls /sys/class/leds/
 input0::capslock input0::scrolllock platform::micmute tpacpi::kbd_backlight tpacpi::standby tpacpi::thinkvantage
 input0::numlock phy0-led platform::mute tpacpi::power tpacpi::thinklight

Thanks.