Re: [PATCH v3 3/3] gpio: add Intel SCH GPIO controller driver

From: Denis Turischev
Date: Tue Mar 02 2010 - 04:28:43 EST

Mike Rapoport wrote:
> Len Brown wrote:
>>> I've looked at two x86 drivers in drivers/gpiolib (cs5535 and langwell) and
>>> there's no treatment of ACPI in either of them. Since SCH is defined by Intel
>>> as "embedded" product, having a GPIO driver for it seems logical even despite
>>> problems you mention.
>> I believe that Langwell is used only in products without an ACPI BIOS.
>> Poulsbo, OTOH, is used in zillions of netbooks running Windows XP.
>> I don't know what a cs5535 is.
> The cs5535 is AMD Geode LX companion chip which is used with ACPI BIOS
> as well.
>> cheers,
>> Len Brown, Intel Open Source Technology Center

I'm really not an ACPI expert too, but as I see in LDD3 "...the role of a device driver
is providing mechanism, not policy".

HW manufacturer must warn users if some GPIOs may conflict with ACPI, and it is user`s
responsibility to use the GPIOs in proper way.

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