Re: rotary encoder linux driver

From: Johan Hovold
Date: Tue Oct 14 2014 - 04:46:08 EST

On Sun, Oct 12, 2014 at 06:29:03PM -0700, tecfacet wrote:
> Hello.
> I am interested in the rotary encoder kernel driver. I am very new to
> this linux kernel driver thing.
> How do I pass the gpio and interrupt stuff to the kernel module.. I
> think it is thru the rotary_encoder.h file.. am I correct?

That should be done through the device tree these days. The binding is
documented in


in the kernel source tree.

> How does the information about encoder position etc get back to my
> user space program? How is debounce handled?
> I am a little confused. Is there an example of a complete working
> implementation? I need to figure this out for school.

Have a look at the evtest program for an example:

Good luck,
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