Re: [PATCH 3/4] dt-bindings: power: reset: Add regmap support to the SYSCON reboot-mode bindings

From: Sergey Semin
Date: Fri Mar 13 2020 - 09:03:18 EST


On Thu, Mar 12, 2020 at 04:14:38PM -0500, Rob Herring wrote:
> On Fri, Mar 06, 2020 at 04:03:40PM +0300, Sergey.Semin@xxxxxxxxxxxxxxxxxxxx wrote:
> > From: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> >
> > Optional regmap property will be used to refer to a syscon-controller
> > having a reboot tolerant register mapped.
>
> NAK. It should simply be a child node of the 'syscon-controller'.

Hm, It's dilemma. The driver maintainer said ack, while you disagree.)
So the code change will be merged while the doc-part won't? Lets discuss then
to settle the issue.

Why 'syscon-reboot' can be out of syscon-controller node, while
'syscon-reboot-mode' can't? They both belong to the same usecase: save
cause id and reboot. So having similar properties-set and declaring their
nodes someplace nearby is natural. According to the driver 'syscon-reboot'
can't lack the regmap property because it's mandatory, while here you refuse
to have even optional support. Additionally in most of the cases the
'syscon-reboot' nodes aren't declared as a child of a system controller
node. Why 'syscon-reboot-mode' can't work in a similar way?

Regards,
-Sergey

>
> >
> > Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
> > Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> > Cc: Paul Burton <paulburton@xxxxxxxxxx>
> > Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
> > ---
> > .../bindings/power/reset/syscon-reboot-mode.yaml | 9 ++++++---
> > 1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/power/reset/syscon-reboot-mode.yaml b/Documentation/devicetree/bindings/power/reset/syscon-reboot-mode.yaml
> > index e09bb07b1abb..f47bf52ad983 100644
> > --- a/Documentation/devicetree/bindings/power/reset/syscon-reboot-mode.yaml
> > +++ b/Documentation/devicetree/bindings/power/reset/syscon-reboot-mode.yaml
> > @@ -13,9 +13,8 @@ description: |
> > This driver gets reboot mode magic value from reboot-mode driver
> > and stores it in a SYSCON mapped register. Then the bootloader
> > can read it and take different action according to the magic
> > - value stored. The SYSCON mapped register is retrieved from the
> > - parental dt-node plus the offset. So the SYSCON reboot-mode node
> > - should be represented as a sub-node of a "syscon", "simple-mfd" node.
> > + value stored. The SYSCON mapped register is retrieved either from
> > + the parental dt-node or from a regmap phandle plus the offset.
> >
> > properties:
> > compatible:
> > @@ -29,6 +28,10 @@ properties:
> > $ref: /schemas/types.yaml#/definitions/uint32
> > description: Offset in the register map for the mode register (in bytes).
> >
> > + regmap:
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > + description: Phandle to the register map node.
> > +
> > patternProperties:
> > "^mode-.+":
> > $ref: /schemas/types.yaml#/definitions/uint32
> > --
> > 2.25.1
> >