Re: [PATCH] iio: misc: add a generic regulator driver

From: Geert Uytterhoeven
Date: Fri Dec 23 2016 - 05:00:50 EST


Hi Lars,

On Mon, Dec 12, 2016 at 6:15 PM, Lars-Peter Clausen <lars@xxxxxxxxxx> wrote:
> On 12/06/2016 12:12 PM, Bartosz Golaszewski wrote:
>> We're already using libiio to read the measured data from the power
>> monitor, that's why we'd like to use the iio framework for
>> power-cycling the devices as well. My question is: would bridging the
>> regulator framework be the right solution? Should we look for
>> something else? Bridge the GPIO framework instead?
>
> I wouldn't necessaries create bridge, but instead just use the GPIO
> framework directly.
>
> We now have the GPIO chardev interface which meant to be used to support
> application specific logic that control the GPIOs, but where you don't want
> to write a kernel driver.
>
> My idea was to add GPIOs and GPIO chips as high level object inside libiio
> that can be accessed through the same context as the IIO devices. Similar to
> the current IIO API you have a API for gpios that allows to enumerate the
> GPIO devices and their pins as well as modify the pin state.

That would mean libiio has access to all GPIOs, allowing a remote person
to not only control through iiod the GPIOs for industrial control, but also the
GPIOs not intended for export, right?

Having a separate GPIO switch driver avoids that, as DT (or some other means)
can be used to specify and label the GPIOs for IIO use.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds