[PATCH] [RFC] pinctrl: mvebu: reset pins to an UNKNOWN state on startup

Linus Walleij linus.walleij at linaro.org
Thu Oct 25 02:51:31 EDT 2012

On Wed, Oct 24, 2012 at 10:21 PM, Thomas Petazzoni
<thomas.petazzoni at free-electrons.com> wrote:
> On Wed, 24 Oct 2012 22:15:45 +0200, Andrew Lunn wrote:

>> If you compare the two, you can see that pin 6 has probably been set by
>> uboot, but not by DT.
> Indeed, by correlating the two files, you can get a good view of which
> pins are configured even though no driver has claimed them.

If it is useful, please consider introducing new debugfs files, that thing
is supposed to be helpful.

For example: if a <debugfs>/pinctrl/pinctrl-foo/pins-probe-state
caching and providing the power-on-state of all pins is useful,
then just add that mechanism to the pinctrl core I'd say.

Linus Walleij

More information about the linux-arm-kernel mailing list