Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f2/STM32F215/OTG_HS_PWRCLK/OTG_HS_PCGCR#0x0
Power and clock gating control register
Stop PHY clock
Gate HCLK
PHY suspended
https://github.com/modm-io/cmsis-svd-stm32