Messages in this thread |  | | Date | Wed, 5 Mar 2014 10:49:41 +0800 | Subject | Re: [PATCH 1/6] gpiolib: Allow GPIO chips to request their own GPIOs | From | Linus Walleij <> |
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On Tue, Feb 25, 2014 at 12:00 AM, Mika Westerberg <mika.westerberg@linux.intel.com> 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 <mika.westerberg@linux.intel.com>
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?
Yours, Linus Walleij
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