[RFC PATCH] ARM: vt8500: Convert arch-vt8500 to multiplatform

[arnd@arndb.de (Arnd Bergmann)]

On Thursday 11 October 2012, linux at prisktech.co.nz wrote:
> To clarify what you said (because I'm not sure I got it the first time)...
> 
> Keep ARCH_VT8500 as the single-platform Kconfig option.
> Add a new ARCH_VT8500_MULTI (for example) as the multiplatform Kconfig option.
> 
> Have ARCH_VT8500_MULTI select ARCH_VT8500??
> 
> The last bit confuses me (and seems a little backwards, although I suspect it
> would work since none of the options would cause conflicts). Without ARCH_VT8500
> selected, we have no driver options without changing all the Kconfig's.
> 
> If this is correct, we are basically using _MULTI to add more options on top of
> _VT8500.

No, this would not work, because Kconfig does not let you 'select' a symbol
that is inside of a 'choice' list.

The other way round works though: rename the existing ARCH_VT8500 to
ARCH_VT8500_SINGLE, and add a new symbol in arch/arm/mach-vt8500/Kconfig
like

config VT8500
       bool "Via/Wondermedia VT8500 / WM8505 / WM8650" if ARCH_MULTI_V5
       default ARCH_VT8500_SINGLE

This one becomes visible when ARCH_MULTI_V5 is set but invisible in a
other cases. The 'default ARCH_VT8500_SINGLE' statement means it is
automatically enabled (but still invisible) if ARCH_VT8500_SINGLE
is selected in the 'choice', and it's invisible and disabled in all
other cases.

	Arnd