Re: [PATCH v5 0/9] Add RZ/G2L POEG support

[Linus Walleij <linus.walleij@linaro.org>]

On Mon, Jan 9, 2023 at 4:10 PM Biju Das <biju.das.jz@bp.renesas.com> wrote:

> > What's wrong with using the debugfs approach Drew implemented in commit
> > 6199f6becc869d30ca9394ca0f7a484bf9d598eb
> > "pinctrl: pinmux: Add pinmux-select debugfs file"
> > ?
>
> I am not sure, we supposed to use debugfs for production environment??

It depends what is meant by "production environment".

If you mean a controlled environment "one-off" such as a factory line,
a specific installation for a specific purpose such as a water purifier,
that is very custom and hacked together for that one usecase. It will
have other hacks too, so then Beagle is using debugfs in "production"
if that is what you mean by "production", i.e. used to produce something.

This is the same "production" use cases as used by i.e. the GPIO
character device.

If you mean that you are producing 6 million laptops where userspace is
going to hammer this constantly, then no. In that case a real sysfs
knob and ABI contract is needed.

Usually vendors know which usecase their hardware is intended for,
there is in my experience no unknown target audience, so which one is it in
your case?

> > such as a list of stuff to be exported as sysfs switches.
>
> Can you please elaborate? Or Point me to an example for this?

Not sure what to say about that, you will have to invent something I'm
afraid, good examples are in Documentation/ABI.

Yours,
Linus Walleij