[PATCH v2 2/4] dt-bindings: ARM: Mediatek: Document devicetree bindings for clock controllers

James Liao jamesjj.liao at mediatek.com
Mon Jul 6 23:56:46 PDT 2015

Hi Daniel,

On Fri, 2015-07-03 at 18:46 +0800, Daniel Kurtz wrote:
> On Fri, Jul 3, 2015 at 7:40 AM, Stephen Boyd <sboyd at codeaurora.org> wrote:
> > DT nodes typically have a reg property. Not having a reg property is a
> > good indicator of a problem with the binding. A syscon is used when you
> > have a DT node with a reg property and some driver attached to it, but
> > you need to poke some bits in another register region that isn't part of
> > the reg property. Instead of having multiple nodes with two reg
> > properties where the second one is the same, we use a phandle and a syscon.
> >
> > If clock-controller isn't acceptable maybe clock-reset-contoller would
> > work? Or "power-controller"? We certainly shouldn't be making up
> > multiple nodes for one hardware block. Of course, the subject of the
> > patch is "bindings for clock controllers", so it may be that the
> > registers are predominantly clock related and so the name is appropriate
> > already.
> Using "clock-controller" seems to fit best with the bindings
> introduced by this patch.
> However, if these bindings are for hardware blocks that contain a grab
> bag of various functionality that will be added in later patches, then
> I think "syscon" might be best.

I referred some dt-binding documents that contain clock and reset
controller in the same unit:


	clock-controller at 900000 {
		compatible = "qcom,gcc-msm8960";


	tegra_car: clock {
		compatible = "nvidia,tegra124-car";


	cru: cru at 20000000 {
		compatible = "rockchip,rk3188-cru";

Rockchip use "Clock and Reset Unit" as their controller's name. The
other two use "clock" or "clock-controller" as their controller's name.

It looks like "clock-controller" is also an acceptable name for
clock/reset controllers. So I would like to keep this name in next

Best regards,


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