[PATCH 1/2] arm64: juno: Add APB registers and LEDs using syscon

Will Deacon will.deacon at arm.com
Wed Feb 25 07:00:23 PST 2015


On Wed, Feb 25, 2015 at 02:47:56PM +0000, Liviu Dudau wrote:
> On Wed, Feb 25, 2015 at 01:55:12PM +0000, Will Deacon wrote:
> > On Wed, Feb 25, 2015 at 12:16:29PM +0000, Linus Walleij wrote:
> > > This defines the Juno "APB system registers" as a syscon device,
> > > and all the LEDs controlled by the APB system registers right
> > > below it using the syscon LEDs driver on top of syscon. Define
> > > LED0 for heartbeat, LED1 for MMC0 activity and the following
> > > four LEDs indicating CPU activity using the Linux-specific
> > > DT bindings for triggers.
> > > 
> > > This is the pattern and same drivers as used on the legacy
> > > platform device trees for the ARM Integrators and the RealView
> > > PB1176.
> > 
> > Stupid question, but where are these LEDs located on the platform? I tried
> > enabling this, but all it seemed to do was make hackbench slightly slower :)
> 
> http://infocenter.arm.com/help/topic/com.arm.doc.ddi0524c/deb1353593789871.html
> 
> Section 1.3, look at the left hand side, above the user push buttons.

Right, so these LEDs are *inside* the case. Is that really something worth
enabling for defconfig?

Will



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