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

[Ulf Hansson]

On 10 November 2016 at 20:58, Rob Herring <robh at kernel.org> wrote:
> 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, are you fine with this? I thought it would be great to get this
in for 4.10 rc1.

Kind regards
Uffe