Re: [RFC] pinctrl: generic: Add DT bindings

From: Linus Walleij
Date: Sat Jun 15 2013 - 19:51:38 EST


On Sun, Jun 16, 2013 at 1:35 AM, Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
> On Saturday 15 June 2013 22:16:13 Heiko Stübner wrote:
>> Am Samstag, 15. Juni 2013, 21:56:05 schrieb Linus Walleij:

>> Disable would the be either
>> bias-disable;
>> or
>> bias-pull-up = <0>;
>>
>> A driver should probably handle both, as both are valid pinconf options or
>> this.
>
> I feel a bit uneasy about that. Do we really need to support two different
> ways to achieve the same result ?

In this specific case I think yes, but not on all options.

As dicussed earlier this was designed for systems where
you could set the pull-up resistance, like

bias-pull-up = <600000>;

would give 600kOhm pull up.

In most existing systems that is silly, as they can't specify
it, so they should be able to do just:

bias-pull-up;

as that is all they can do. If we have to cut one way, we
should cut the former until such a system appears.

Yours,
Linus Walleij
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