Pulls and drive strengths in the pinctrl world

[Olof Johansson]

On Wed, May 15, 2013 at 10:26 AM, Tomasz Figa <tomasz.figa at gmail.com> wrote:

>> I don't want to specify function/direction (code can handle that), but
>> do wish I could specify the pulls and strength.  Perhaps:
>>
>>   ptn3460-bridge at 20 {
>>     compatible = "nxp,ptn3460";
>>     reg = <0x20>;
>>     powerdown-gpio = <&gpy2 5 0 0 0>;
>>     reset-gpio = <&gpx1 5 0 0 0>;
>
> This looks fine to me as well.
>
> Implementation of both shouldn't be too complicated, so it might be worth
> giving a try. Keep in mind that old bindings must be supported as well
> (based on #interrupt-cells and #gpio-cells values, I guess).

Given the late discovery of this pretty major drawback, I don't think
we should worry too much about backwards compatibility in this case
and instead just move everyone over asap to whatever the new binding
is (when we agree on something).

Also, it looks like the gpio bindings were never updated with the
pinctrl changes. Tsk, tsk, tsk. Bad.

We have the option of either adding new fields for pulls and strength,
but we can also split the existing flags field similar to how we did
with the old binding, and take 8 bits each for pulls and strength, or
somesuch. That'll be less of a change w.r.t. existing device trees and
bindings.



-Olof