On 03/03/2017 02:00 PM, Fabrice Gasnier wrote: > On 03/03/2017 12:45 PM, Lars-Peter Clausen wrote: >> On 02/28/2017 05:51 PM, Fabrice Gasnier wrote: >>> EXTi (external interrupt) signal can be routed internally as trigger >>> source for ADC conversions: STM32F4 ADC can use EXTI11. >>> >>> Retrieve interrupt trigger from DT, so it can be muxed into ADC IP, >>> via extsel. >> >> Hi, >> >> Sorry, I have some trouble understanding the specifics of this. Is EXTI a >> hardware input signal into the ADC that automatically triggers a conversion >> when asserted? If yes how is it configured which external signal is used >> here. Your bindings suggest that any GPIO can be used, but the driver only >> differentiates between EXTI on or EXTI off. > Hi Lars, > > Yes, STM32 EXTI is external interrupt/event line. In case of STM32 ADC, > EXTI11 signal can be used to start a conversion. In this case, it must > be selected inside ADC IP using extsel bitfield. This EXTI11 line can > mapped from any GPIO bank A,B... line 11 (e.g. PA11 or PB11...) by using > interrupt binding. > This is why I expose this in DT. How is the mapping? That's the part I don't understand. How does requesting the IRQ for the GPIO as a generic software IRQ establish the hardware connection between the GPIO block and the ADC? -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
