RM0394 Rev. 4 chapter 16.4.2 clocks should note in a preamble or something similar that Dual clock and ADC12_CLK is not available on STM32L412. Reading through RM0394 I conclude that ADC clock is HCLK fixed on L412, but I don't see it stated anywhere. If the description in 6.4.27 for Bits 28/29 whould state the ADC Clock for STM32L412 is HCLK fixed, thing would be clearer.
@Uwe Bonnes , maybe you want also to fix the number of RM in the title, so that it could be easier to look up this post when needed (also in the other thread you posted yesterday).
