[PATCH 2/3] ARM: ux500: Turn on the 'heartbeat' LED trigger

[Russell King - ARM Linux]

On Wed, Jan 09, 2013 at 11:08:40AM +0000, Lee Jones wrote:
> On Wed, 09 Jan 2013, Russell King - ARM Linux wrote:
> 
> > On Wed, Jan 09, 2013 at 10:18:54AM +0000, Arnd Bergmann wrote:
> > > On Wednesday 09 January 2013, Lee Jones wrote:
> > > > diff --git a/arch/arm/mach-ux500/Kconfig b/arch/arm/mach-ux500/Kconfig
> > > > index 5dea906..0f25b07 100644
> > > > --- a/arch/arm/mach-ux500/Kconfig
> > > > +++ b/arch/arm/mach-ux500/Kconfig
> > > > @@ -43,6 +43,8 @@ config MACH_HREFV60
> > > >  config MACH_SNOWBALL
> > > >         bool "U8500 Snowball platform"
> > > >         select MACH_MOP500
> > > > +       select LEDS_TRIGGERS
> > > > +       select LEDS_TRIGGER_HEARTBEAT
> > > >         help
> > > >           Include support for the snowball development platform.
> > > 
> > > Be careful with "select" statements like this when there are other
> > > dependencies. I think LEDS_TRIGGERS depends on LEDS_CLASS, so this
> > > should probably be written as
> > > 
> > > 	select LEDS_TRIGGERS if LEDS_CLASS
> > 
> > Umm, this is also wrong for another reason.  LEDS is an optional feature.
> > It's not required for the platform to be functional.  So why the hell would
> > anyone want to _force_ such an optional feature to be mandatory?
> > 
> > This is something that the default config published for the platform should
> > be handling.
> 
> Do you mean <config_dir>/u8500_defconfig?
> 
> If so, that's wrong, as it covers many more boards than just Snowball
> and this is only applicable on the Snowball board. So how else can
> I enable this feature?

And why is it wrong to enable an optional feature in a defconfig which some
boards using that defconfig may want?

It's _less_ wrong than forcing user selectable options to be mandatorily
selected.