Messages in this thread | | | From | Linus Walleij <> | Date | Tue, 31 Oct 2017 14:27:13 +0100 | Subject | Re: [PATCH] pinctrl: armada-37xx: Add edge both type gpio irq support |
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On Tue, Oct 31, 2017 at 2:16 PM, Andrew Lunn <andrew@lunn.ch> wrote:
>> The discussion here is interesting, it is customary for GPIO drivers >> to implement double-edge detection emulation by swapping the >> edge detector around like this. > > Hi Linus > > I was not aware this was customary. > >> It might be possible to collect some generic information about >> this in the Documentation/gpio/driver.txt document. > > Yes, i think it should be documented somewhere. Even in the use case > here, detecting an SD card being inserted/removed, you could get some > bounce on the microswitch, miss an edge, and be in the wrong state.
Indeed :/
This is I guess why it is a good idea to combine this with the debounce feature if the hardware supports it.
I'll think about some writeup.
Yours, Linus Walleij
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