Re: [PATCH v9 2/4] pinctrl: pinmux: Add pinmux-select debugfs file

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Fri, Mar 12, 2021 at 2:57 PM Enrico Weigelt, metux IT consult
<lkml@xxxxxxxxx> wrote:
> On 02.03.21 06:30, Drew Fustini wrote:
>
> Hi folks,
>
> > Add "pinmux-select" to debugfs which will activate a pin function for a
> > given pin group:
> >
> >    echo "<group-name function-name>" > pinmux-select
> >
> > The write operation pinmux_select() handles this by checking that the
> > names map to valid selectors and then calling ops->set_mux().
>
> I've already been playing with similar idea, but for external muxes.
> For example, some boards have multiple SIM slots that can be switched
> via some gpio pin.
>
> Not sure whether traditional pinmux would be a good match for that.

What is wrong with the subsystem
drivers/mux?

It's exactly for this usecase I think. Peter Rosin already wrote
a GPIO-controlled mux driver too.

Yours,
Linus Walleij