[PATCH] PM / Domains: Fix compatible for domain idle state

[Rob Herring]

On Mon, Nov 07, 2016 at 12:14:28PM +0100, Ulf Hansson wrote:
> On 3 November 2016 at 22:54, Lina Iyer <lina.iyer at linaro.org> wrote:
> > Re-using idle state definition provided by arm,idle-state for domain
> > idle states creates a lot of confusion and limits further evolution of
> > the domain idle definition. To keep things clear and simple, define a
> > idle states for domain using a new compatible "domain-idle-state".
> >
> > Fix existing PM domains code to look for the newly defined compatible.
> >
> > Cc: <devicetree at vger.kernel.org>
> > Cc: Rob Herring <robh at kernel.org>
> > Signed-off-by: Lina Iyer <lina.iyer at linaro.org>
> > ---
> >  .../bindings/power/domain-idle-state.txt           | 33 ++++++++++++++++++++++
> >  .../devicetree/bindings/power/power_domain.txt     |  8 +++---
> >  drivers/base/power/domain.c                        |  2 +-
> >  3 files changed, 38 insertions(+), 5 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/power/domain-idle-state.txt
> >
> > diff --git a/Documentation/devicetree/bindings/power/domain-idle-state.txt b/Documentation/devicetree/bindings/power/domain-idle-state.txt
> > new file mode 100644
> > index 0000000..eefc7ed
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/power/domain-idle-state.txt
> > @@ -0,0 +1,33 @@
> > +PM Domain Idle State Node:
> > +
> > +A domain idle state node represents the state parameters that will be used to
> > +select the state when there are no active components in the domain.
> > +
> > +The state node has the following parameters -
> > +
> > +- compatible:
> > +       Usage: Required
> > +       Value type: <string>
> > +       Definition: Must be "domain-idle-state".
> > +
> > +- entry-latency-us
> > +       Usage: Required
> > +       Value type: <prop-encoded-array>
> > +       Definition: u32 value representing worst case latency in
> > +                   microseconds required to enter the idle state.
> > +                   The exit-latency-us duration may be guaranteed
> > +                   only after entry-latency-us has passed.
> 
> As we anyway are going to change this, why not use an u64 and have the
> value in ns instead of us?

I can't imagine that you would need more resolution or range. For times 
less than 1us, s/w and register access times are going to dominate the 
time.

Unless there is a real need, I'd keep alignment with the existing 
binding.

Rob