Isso acabou funcionando:
Section "InputClass"
Identifier "KeyboardLayout"
Driver "evdev"
MatchIsKeyboard "yes"
Option "XkbLayout" "us,ru"
Option "XkbOptions" "grp:ctrl_shift_toggle,caps:ctrl_modifier,compose:sclk,terminate:ctrl_alt_bksp,grp_led:scroll"
EndSection