[PATCH 3/7] IBM Akebono: Add support for a new PHY to the IBM emac driver

[Ben Hutchings]

On Wed, 2013-11-06 at 12:34 +1100, Alistair Popple wrote:
> On Tue, 5 Nov 2013 23:11:50 Ben Hutchings wrote:
> > On Wed, 2013-11-06 at 06:54 +1100, Benjamin Herrenschmidt wrote:
> 
> [snip]
> 
> > > It's an SoC bit so there's little point making it generally
> > > selectable by the user.
> > 
> > I think a better way to do this is:
> > 
> > config IBM_EMAC_RGMII_WOL
> > 	bool "IBM EMAC RGMII wake-on-LAN support"
> > 	depends on MY_WONDERFUL_NEW_SOC || COMPILE_TEST
> > 	default y if MY_WONDERFUL_NEW_SOC
> > 
> > Then anyone making an API change that affects this driver can check that
> > it still complies.
> 
> The method used in this patch is the same as what is currently used by the 
> other IBM EMAC PHY interfaces (eg. config IBM_EMAC_ZMII etc). I'm happy to 
> send a patch to update all of those as well for consistency but that would 
> mean adding what each platform requires into EMACS Kconfig as well.
> 
> Personally I think it is nicer to keep the definitions of what each platform 
> requires in one place (ie. arch/powerpc/platforms/44x/Kconfig) as it is 
> consistent with what we do for other 44x drivers, however I am happy to use 
> the above method if people think it's better.

Yes, I see your point.

> Alternatively we could do something like this:
> 
> config IBM_EMAC_RGMII_WOL
>         bool
>         default y if COMPILE_TEST
>         default n
> 
> This would leave the platform dependencies as they are currently but still 
> allow compile testing.

It still shouldn't default to y in that case.  Instead you can make the
symbol conditionally configurable:

config IBM_EMAC_RGMII_WOL
	bool "IBM EMAC RGMII wake-on-LAN support" if COMPILE_TEST

and then select this from your platform Kconfig as you intended.

(There is no need to put 'default n' as that's implicit for a
configurable symbol.  But it doesn't hurt either.)

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.