Re: [PATCH v5 01/10] pinctrl: generic: Add bi-directional and output-enable

From: Linus Walleij
Date: Fri May 12 2017 - 05:01:12 EST


On Tue, May 9, 2017 at 12:54 PM, Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:

> The question I'm asking myself is: are these settings related to pin
> configuration (i.e. depending on the use of the pin, and several settings
> are valid, depending on the use case), or are they related to pinmux
> (i.e. defined by the function)?

If they are intrinsic to the function, i.e. whenever someone wants to use
that function they need to do this (nb the Documentation/pinctrl.txt
definition of "function", nothing else) then this should IMO not be in
the device tree at all, but hard-coded in the driver.

E.g. if someone needs to use a function such as "i2c0", on whatever
pins, then it should just be set up by the driver, no DT involved. It is a
hardware pecularity, drivers drive hardware so...

If however it depends on which pins it is used with, then it is pin
configuration and should use a DT property.

Yours,
Linus Walleij