Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f7/STM32F767/TIM1/AF1#0x0
alternate function option register 1
BRK BKIN input enable
BRK DFSDM_BREAK[0] enable
BRK BKIN input polarity
https://github.com/modm-io/cmsis-svd-stm32