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SubjectRe: [PATCH 1/6] gpiolib: Allow GPIO chips to request their own GPIOs
On Tue, Feb 25, 2014 at 12:00 AM, Mika Westerberg
<> wrote:

> Sometimes it is useful to allow GPIO chips themselves to request GPIOs they
> own through gpiolib API. One usecase is ACPI ASL code that should be able
> to toggle GPIOs through GPIO operation regions.
> We can't really use gpio_request() and its counterparts because it will pin
> the module to the kernel forever (as it calls module_get()). Instead we
> provide a gpiolib internal functions gpiochip_request/free_own_desc() that
> work the same as gpio_request() but don't manipulate module refrence count.
> Since it's the GPIO chip driver who requests the GPIOs in the first place
> we can be sure that it cannot be unloaded without the driver knowing about
> that. Furthermore we only limit this functionality to be available only
> inside gpiolib.
> Signed-off-by: Mika Westerberg <>

I fully trust you in doing the ACPI stuff in patches 2-n but on this patch
in particular I want Alexandre's review tag as well, as he's working
actively with the descriptor API and I don't want to add too many quirks
without his consent.

So Alexandre, what do you say about this?

Linus Walleij

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