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    SubjectRe: [PATCH] gpio: add support for ITE IT87xx Super I/O GPIO.
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    On Mon, 2012-03-19 at 10:05 -0400, Linus Walleij wrote:
    > On Mon, Mar 19, 2012 at 2:56 PM, Guenter Roeck
    > <guenter.roeck@ericsson.com> wrote:
    > > On Mon, Mar 19, 2012 at 04:26:44AM -0400, Linus Walleij wrote:
    >
    > >> OK that is pinmuxing, if that is to be software-controlled the place to do
    > >> it is in drivers/pinctrl. (Documentation/pinctrl.txt gives the backrgound.)
    > (...)
    > >>
    > > Personally I would not dare touch those pins. If a pin is configured as UART pin
    > > (or whatever), it is quite unlikely that it is exposed as GPIO pin. Worst case,
    > > changing the configuration may result in broken hardware. Not sure what is supposed
    > > to be gained by enabling the user to do that.
    >
    > Define "user", pinctrl does not have userspace interfaces if that's
    > what you mean.
    >
    > If you mean "kernel programmer", these creatures seem to not respect what
    > they should and shouldn't poke at ;-)
    >
    > The usecase is typically if the hardware is used in two different systems
    > where the ROM/bootcode/etc does not set up muxing correctly, or are setup
    > in a sub-optimal way (e.g. working but consuming too much power) and the
    > kernel needs to get involved. Unless you have any scenario like that, no
    > need to worry about it.
    >
    Ok, guess that makes sense.

    Thanks,
    Guenter




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