Re: [PATCH v3 1/3] dt-bindings: bus: simple-pm-bus: convert bindings to json-schema

[Simon Horman <horms@verge.net.au>]

On Fri, Sep 27, 2019 at 01:38:44PM -0500, Rob Herring wrote:
> On Tue, Sep 24, 2019 at 11:36:07AM +0200, Simon Horman wrote:
> > Convert Simple Power-Managed Bus bindings documentation to json-schema.
> > 
> > As a side effect of this change only simple-pm-bus is used in example. A
> > follow-up patch will provide an example for the separately documented
> > Renesas Bus State Controller (BSC) that uses "renesas,bsc-sh73a0" and
> > "renesas,bsc" compat strings.
> > 
> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> > ---
> > * Based on v5.3
> > * Tested using:
> >   # ARCH=arm64 make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/bus/simple-pm-bus.yaml
> >   # ARCH=arm   make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/bus/simple-pm-bus.yaml
> > 
> > v2
> > * Add SPDX line
> > * Remove extra blank line
> > * Add $nodename
> > * Remove extra leading space in compatible
> > * Update compatible to allow override by other schemas
> > * Allow #size-cells to be 1 or 2
> > * Do not limit ranges or clocks to 1 item
> > * Add anyOf requirement on ranges or clocks
> > * Update example based on msm8996.dtsi
> > ---
> >  .../devicetree/bindings/bus/simple-pm-bus.txt      | 44 -------------
> >  .../devicetree/bindings/bus/simple-pm-bus.yaml     | 75 ++++++++++++++++++++++
> >  2 files changed, 75 insertions(+), 44 deletions(-)
> >  delete mode 100644 Documentation/devicetree/bindings/bus/simple-pm-bus.txt
> >  create mode 100644 Documentation/devicetree/bindings/bus/simple-pm-bus.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/bus/simple-pm-bus.txt b/Documentation/devicetree/bindings/bus/simple-pm-bus.txt
> > deleted file mode 100644
> > index 6f15037131ed..000000000000
> > --- a/Documentation/devicetree/bindings/bus/simple-pm-bus.txt
> > +++ /dev/null
> > @@ -1,44 +0,0 @@
> > -Simple Power-Managed Bus
> > -========================
> > -
> > -A Simple Power-Managed Bus is a transparent bus that doesn't need a real
> > -driver, as it's typically initialized by the boot loader.
> > -
> > -However, its bus controller is part of a PM domain, or under the control of a
> > -functional clock.  Hence, the bus controller's PM domain and/or clock must be
> > -enabled for child devices connected to the bus (either on-SoC or externally)
> > -to function.
> > -
> > -While "simple-pm-bus" follows the "simple-bus" set of properties, as specified
> > -in the Devicetree Specification, it is not an extension of "simple-bus".
> > -
> > -
> > -Required properties:
> > -  - compatible: Must contain at least "simple-pm-bus".
> > -		Must not contain "simple-bus".
> > -		It's recommended to let this be preceded by one or more
> > -		vendor-specific compatible values.
> > -  - #address-cells, #size-cells, ranges: Must describe the mapping between
> > -		parent address and child address spaces.
> > -
> > -Optional platform-specific properties for clock or PM domain control (at least
> > -one of them is required):
> > -  - clocks: Must contain a reference to the functional clock(s),
> > -  - power-domains: Must contain a reference to the PM domain.
> > -Please refer to the binding documentation for the clock and/or PM domain
> > -providers for more details.
> > -
> > -
> > -Example:
> > -
> > -	bsc: bus@fec10000 {
> > -		compatible = "renesas,bsc-sh73a0", "renesas,bsc",
> > -			     "simple-pm-bus";
> > -		#address-cells = <1>;
> > -		#size-cells = <1>;
> > -		ranges = <0 0 0x20000000>;
> > -		reg = <0xfec10000 0x400>;
> > -		interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
> > -		clocks = <&zb_clk>;
> > -		power-domains = <&pd_a4s>;
> > -	};
> > diff --git a/Documentation/devicetree/bindings/bus/simple-pm-bus.yaml b/Documentation/devicetree/bindings/bus/simple-pm-bus.yaml
> > new file mode 100644
> > index 000000000000..598b71d779b1
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/bus/simple-pm-bus.yaml
> > @@ -0,0 +1,75 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/bus/simple-pm-bus.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Simple Power-Managed Bus
> > +
> > +maintainers:
> > +  - Geert Uytterhoeven <geert+renesas@glider.be>
> > +
> > +description: |
> > +  A Simple Power-Managed Bus is a transparent bus that doesn't need a real
> > +  driver, as it's typically initialized by the boot loader.
> > +
> > +  However, its bus controller is part of a PM domain, or under the control
> > +  of a functional clock.  Hence, the bus controller's PM domain and/or
> > +  clock must be enabled for child devices connected to the bus (either
> > +  on-SoC or externally) to function.
> > +
> > +  While "simple-pm-bus" follows the "simple-bus" set of properties, as
> > +  specified in the Devicetree Specification, it is not an extension of
> > +  "simple-bus".
> > +
> > +properties:
> > +  $nodename:
> > +    pattern: "^bus([@-][0-9a-f]+)?$"
> 
> Why the '-' (bus-)? That's only for a few cases where there's no 
> addressing like i2c-gpio.

Thanks, I will drop the '-'.

> 
> > +
> > +  compatible:
> > +    contains:
> > +      const: simple-pm-bus
> > +    description:
> > +      Shall contain "simple-pm-bus" in addition to a optional bus-specific
> > +      compatible strings defined in individual pm-bus bindings.
> > +
> > +  '#address-cells':
> > +    const: 1
> 
> This too can be 2 cells...

Thanks, I'll fix that.

> > +
> > +  '#size-cells':
> > +    enum: [ 1, 2 ]
> > +
> > +  ranges: true
> > +
> > +  clocks: true
> > +    # Functional clocks
> > +    # Required if power-domains is absent, optional otherwise
> > +
> > +  power-domains:
> > +    # Required if clocks is absent, optional otherwise
> > +    minItems: 1
> > +
> > +required:
> > +  - compatible
> > +  - '#address-cells'
> > +  - '#size-cells'
> > +  - ranges
> > +
> > +anyOf:
> > +  - required:
> > +      - clocks
> > +  - required:
> > +      - power-domains
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/clock/qcom,gcc-msm8996.h>
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +
> > +    bus {
> > +        power-domains = <&gcc AGGRE0_NOC_GDSC>;
> > +        compatible = "simple-pm-bus";
> > +        #address-cells = <1>;
> > +        #size-cells = <1>;
> > +        ranges;
> > +    };
> > -- 
> > 2.11.0
> > 
>