On Fri, Feb 15, 2013 at 12:40:00PM +0530, Omair M. Abdullah wrote:
This patch is mainly to handle GPIOs where there is some toggling of the GPIO lines due to the switch bouncing, and the debounce time cannot be increased further due to other constraints. In such cases, providing the specific edge on which to trigger the interrupt helps increase the robustness.
___ _ _ _________e.g. |_| |______________| |_|
insert followed by removal, where we want to trigger on the falling edge in both cases.
This doesn't make much sense to me, it's a *very* non-obvious change and it doesn't reflect what's actually happening well. If you happen to be lucky and get no bounce it'll fail. If it's working on your system there is a fair element of luck in there.
It sounds like all you're looking for here is a better debounce algorithm, for example one that delays for a bit then starts polling the GPIO state at a higher rate and declares a result when the GPIO state doesn't change for a few polls.