Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/EFR32BG22C222F352GN32/GPIO_S/PRS0_ASYNCH4ROUTE#0x0
ASYNCH4 port/pin select
ASYNCH4 port select register
ASYNCH4 pin select register
https://github.com/cmsis-svd/cmsis-svd-data