Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f7/STM32F722/OTG_FS_GLOBAL/OTG_FS_GI2CCTL#0x0
OTG I2C access register
I2C Read/Write Data
I2C Register Address
I2C Address
I2C Enable
I2C ACK
I2C Device Address
I2C DatSe0 USB mode
Read/Write Indicator
I2C Busy/Done
https://github.com/modm-io/cmsis-svd-stm32