Re: [PATCH] mtd: nand: add FSL_SOC dependency to drivers using FSL_LBC

[Scott Wood <scottwood@freescale.com>]

On Thu, 2016-01-07 at 11:21 -0800, Brian Norris wrote:
> I've managed to construct .config files (for ppc64) that come across
> this Kconfig warning:
> 
>   warning: (MPC836x_RDK && MTD_NAND_FSL_ELBC && MTD_NAND_FSL_UPM) selects
> FSL_LBC which has unmet direct dependencies (FSL_SOC)
> 
> Let's add the FSL_SOC dependency to the NAND drivers. AFAICT, they are
> only supported on PPC32 FSL SoCs anyway.

There are other problems, if you can enable an 83xx board on ppc64.  PPC_83xx
does select FSL_SOC so I don't know why it's unmet.

FWIW, I think we should instead drop the FSL_SOC dependency from FSL_LBC.  It
doesn't use anything that I can see from fsl_soc.c.  It's been commonly abused
as a means for hiding the option on builds for other platforms, but that has
to stop anyway now that many of these devices are also on ARM-based chips. 
 eLBC isn't, since it was obsoleted by IFC, but it shouldn't be unnecessarily
different from IFC.  IFC currently depends on FSL_SOC but that needs to go
away.

-Scott