[Buildroot] How to configure Linux with "Device Drivers->GPIO support"

[Чинков Андрей]

Good Day.
I selected advanced Linux kernel configuration option from "make 
menuconfig" invoked in .../buildroot directory.

So all is OK with Linux building but the question1 is:
why in Linux configuration session "Device Drivers -> GPIO Support" is 
absent?

I have target "AMD Alchemy Processor", MIPSel architecture.

If I invoke "make menuconfig" in linux-2.6.27 directory by hand then 
there will be "Device Drivers -> GPIO Support" option.

So the question2 is:
is the option "Device Drivers -> GPIO Support" absent due to some 
special patches applied?

And question3:
is it able to build Linux from some existing linux_configuration_file ?

Thanks.

--
Andrew