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SubjectRe: [PATCH] pinctrl: samsung: Allow pin value to be initialized using pinfunc.
On 05/12/2013 17:11, Tomasz Figa wrote:
> On Thursday 05 of December 2013 15:07:47 Mark Brown wrote:
>> On Tue, Dec 03, 2013 at 10:29:42AM +0100, Linus Walleij wrote:
>>
>>> So a suggested patch to support weak hogs would be interesting
>>> to look at. Can you provide details on how you think this would
>>> work?
>> Or should we be going and applying the default state to all devices on
>> init without worrying about a driver appearing?
> If a device isn't used, then it's often better to configure the pins for
> a different function, such as GPIO, to minimize leakage current.
>

And there can also be mutually-exclusive drivers choosing different
default states for the same pin. I think you do need a separate "safe"
indicator.

My current thought is that a late-init "make safe all unclaimed pins"
pass would make sense - you can't really mess with pins in an automated
fashion on init, as it can mess up bootloader->driver handover. There
already exist late-init "turn off all unclaimed clocks" (at least on
shmobile) and "turn off all unclaimed regulators", and it would fit that
model.

Kevin



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