Messages in this thread | | | Date | Thu, 05 Dec 2013 18:49:56 +0200 | From | Kevin Bracey <> | Subject | Re: [PATCH] pinctrl: samsung: Allow pin value to be initialized using pinfunc. |
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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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