STM32_ENVR
ret = readl_relaxed(priv->base + STM32_VREFBUF_CSR) & STM32_ENVR;
val = (val & ~STM32_HIZ) | STM32_ENVR;
val = (val & ~STM32_ENVR) | STM32_HIZ;
val &= ~STM32_ENVR;