Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/Series1/EFM32GG12B/EFM32GG12B410F1024IL112/USB/HC3_SPLT#0x0
Host Channel x Split Control Register
Port Address
Hub Address
Transaction Position
Do Complete Split
Split Enable
https://github.com/cmsis-svd/cmsis-svd-data