Re: [PATCH 1/3] edt-ft5x06: fix reset pin behaviour

[Simon Budig <simon.budig@kernelconcepts.de>]

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Hi Dmitry.

On Mon, 2017-10-09 at 20:58 -0700, Dmitry Torokhov wrote:
> On Thu, Oct 05, 2017 at 05:35:06PM +0200, simon.budig@kernelconcepts.
> de wrote:
> > From: Simon Budig <simon.budig@kernelconcepts.de>
> > 
> > For some reason the reset pin no longer gets toggeled when
> > initializing
> > the touch. Fix that and restore the old behaviour.
> 
> Hmm, the GPIO is requested as GPIOD_OUT_HIGH, so it should be driven
> low
> to being with and then released... I am not sure why we need to drive
> it
> low explicitly again.

It is possible that I misinterpreted something here - at some point I
did have the GPIO pin wrongly registered in the devicetree.

However, API-wise it is not clear to me, that GPIOD_OUT_HIGH results in
an actual low state of the Pin. That might be different if the constant
was called GPIOD_OUT_ACTIVE or something, since this would refer to the
"low_active" state of the pin.

*If* that is actually the case (i.e. requesting an pin specified as
GPIO_ACTIVE_LOW in the devicetree with the GPIOD_OUT_HIGH flag results
in 0V on this pin) then this patch should probably be dropped, although
I don't like how this code reads then.

I also reread the focaltec datasheet and I've messed up the delays in
this patch, so if the above does *not* happen then I'd need to rework
this...

Bye,
        Simon

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