On Mon, Jan 30, 2017 at 2:57 PM, Fabrice Gasnier [off-list ref] wrote:

Add dt documentation for st,stm32-exti-trigger.
EXTi gpio signal can be routed internally as trigger source for various
IPs (e.g. for ADC or DAC conversions).

And you say this is done using pin control, elsewhere in the conversation
if I understand it correctly?

+Contents of a stm32 exti trigger root node:
+-------------------------------------------
+Required properties:
+- compatible: Should be "st,stm32-exti-trigger"
+- extiN-gpio: optional gpio line that may be used as external trigger source
+  (e.g. N may be 0..15. For example, exti11-gpio can trig ADC on stm32f4).
+
+Example:
+       triggers {
+               compatible = "st,stm32-exti-trigger";
+               exti11-gpio=<&gpioa 11 0>;
+       };

So what I do not understand i if this has any stm32-specific behaviour at all,
so that compatible-string has any meaning.

Should we not rather define compatible = "gpio-trigger"; to be used by
everyone? Especially for the device tree?

If it's "mostly generic, a bit specific too" it should likely be:

compatible = "gpio-trigger", "st,stm32-exit-trigger";

Yours,
Linus Walleij