Re: [PATCH v6 01/12] dt-bindings: display/msm: split qcom,mdss bindings

[Rob Herring <robh@kernel.org>]

On Thu, Sep 08, 2022 at 03:37:38PM +0200, Krzysztof Kozlowski wrote:
> On 01/09/2022 12:23, Dmitry Baryshkov wrote:
> > Split Mobile Display SubSystem (MDSS) root node bindings to the separate
> > yaml file. Changes to the existing (txt) schema:
> >  - Added optional "vbif_nrt_phys" region used by msm8996
> >  - Made "bus" and "vsync" clocks optional (they are not used by some
> >    platforms)
> >  - Added (optional) "core" clock added recently to the mdss driver
> >  - Added optional resets property referencing MDSS reset
> >  - Defined child nodes pointing to corresponding reference schema.
> >  - Dropped the "lut" clock. It was added to the schema by mistake (it is
> >    a part of mdp4 schema, not the mdss).
> > 
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >  .../devicetree/bindings/display/msm/mdp5.txt  |  30 +---
> >  .../devicetree/bindings/display/msm/mdss.yaml | 166 ++++++++++++++++++
> >  2 files changed, 167 insertions(+), 29 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/display/msm/mdss.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/display/msm/mdp5.txt b/Documentation/devicetree/bindings/display/msm/mdp5.txt
> > index 43d11279c925..65d03c58dee6 100644
> > --- a/Documentation/devicetree/bindings/display/msm/mdp5.txt
> > +++ b/Documentation/devicetree/bindings/display/msm/mdp5.txt
> > @@ -2,37 +2,9 @@ Qualcomm adreno/snapdragon MDP5 display controller
> >  
> >  Description:
> >  
> > -This is the bindings documentation for the Mobile Display Subsytem(MDSS) that
> > -encapsulates sub-blocks like MDP5, DSI, HDMI, eDP etc, and the MDP5 display
> > +This is the bindings documentation for the MDP5 display
> >  controller found in SoCs like MSM8974, APQ8084, MSM8916, MSM8994 and MSM8996.
> >  
> > -MDSS:
> > -Required properties:
> > -- compatible:
> > -  * "qcom,mdss" - MDSS
> > -- reg: Physical base address and length of the controller's registers.
> > -- reg-names: The names of register regions. The following regions are required:
> > -  * "mdss_phys"
> > -  * "vbif_phys"
> > -- interrupts: The interrupt signal from MDSS.
> > -- interrupt-controller: identifies the node as an interrupt controller.
> > -- #interrupt-cells: specifies the number of cells needed to encode an interrupt
> > -  source, should be 1.
> > -- power-domains: a power domain consumer specifier according to
> > -  Documentation/devicetree/bindings/power/power_domain.txt
> > -- clocks: device clocks. See ../clocks/clock-bindings.txt for details.
> > -- clock-names: the following clocks are required.
> > -  * "iface"
> > -  * "bus"
> > -  * "vsync"
> > -- #address-cells: number of address cells for the MDSS children. Should be 1.
> > -- #size-cells: Should be 1.
> > -- ranges: parent bus address space is the same as the child bus address space.
> > -
> > -Optional properties:
> > -- clock-names: the following clocks are optional:
> > -  * "lut"
> > -
> >  MDP5:
> >  Required properties:
> >  - compatible:
> > diff --git a/Documentation/devicetree/bindings/display/msm/mdss.yaml b/Documentation/devicetree/bindings/display/msm/mdss.yaml
> > new file mode 100644
> > index 000000000000..8860fc55cca5
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/display/msm/mdss.yaml
> > @@ -0,0 +1,166 @@
> > +# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/display/msm/mdss.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Qualcomm Mobile Display SubSystem (MDSS)
> > +
> > +maintainers:
> > +  - Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > +  - Rob Clark <robdclark@gmail.com>
> > +
> > +description:
> > +  This is the bindings documentation for the Mobile Display Subsytem(MDSS) that
> > +  encapsulates sub-blocks like MDP5, DSI, HDMI, eDP, etc.
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - qcom,mdss
> > +
> > +  reg:
> > +    minItems: 2
> > +    maxItems: 3
> > +
> > +  reg-names:
> > +    minItems: 2
> > +    items:
> > +      - const: mdss_phys
> > +      - const: vbif_phys
> > +      - const: vbif_nrt_phys
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  interrupt-controller:
> > +    true
> 
> If there is going to be v7 - please make it one line.
> 
> > +
> > +  "#interrupt-cells":
> > +    const: 1
> > +
> > +  power-domains:
> > +    maxItems: 1
> > +    description: |
> > +      The MDSS power domain provided by GCC
> > +
> > +  clocks:
> > +    minItems: 1
> > +    items:
> > +      - description: Display abh clock
> > +      - description: Display axi clock
> > +      - description: Display vsync clock
> > +
> > +  clock-names:
> > +    minItems: 1
> > +    items:
> > +      - const: iface
> > +      - const: bus
> > +      - const: vsync
> > +
> > +  "#address-cells":
> > +    const: 1
> > +
> > +  "#size-cells":
> > +    const: 1
> > +
> > +  ranges:
> > +    true
> 
> Ditto.
> 
> > +
> > +  resets:
> > +    items:
> > +      - description: MDSS_CORE reset
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - reg-names
> > +  - interrupts
> > +  - interrupt-controller
> > +  - "#interrupt-cells"
> > +  - power-domains
> > +  - clocks
> > +  - clock-names
> > +  - "#address-cells"
> > +  - "#size-cells"
> > +  - ranges
> > +
> > +patternProperties:
> > +  "^mdp@[1-9a-f][0-9a-f]*$":
> > +    type: object
> > +    properties:
> > +      compatible:
> > +        const: qcom,mdp5
> > +
> > +  "^dsi@[1-9a-f][0-9a-f]*$":
> > +    type: object
> > +    properties:
> > +      compatible:
> > +        const: qcom,mdss-dsi-ctrl
> 
> This should be ref to dsi-controller-main.yaml... or based on previous
> Rob's feedback you dropped it everywhere in children?

I don't think I said. I thought about it some, as yes, we normally have 
done as you suggested. The downside is with a ref we'll do the whole
validation of the child node twice (unless the referenced schema has a 
'select: false') whereas here only 'compatible' is validated twice. This 
way also complicates checking for unevaluatedProperties/additionalProperties.

So maybe better to keep with the 'normal' way and make this a ref. 

Rob