Re: [PATCH v11 01/10] dt-bindings: mediatek,dp: Add Display Port binding

[Rex-BC Chen <rex-bc.chen@mediatek.com>]

On Tue, 2022-06-14 at 14:23 -0600, Rob Herring wrote:
> On Fri, Jun 10, 2022 at 06:55:13PM +0800, Bo-Chen Chen wrote:
> > From: Markus Schneider-Pargmann <msp@baylibre.com>
> > 
> > This controller is present on several mediatek hardware. Currently
> > mt8195 and mt8395 have this controller without a functional
> > difference,
> > so only one compatible field is added.
> > 
> > The controller can have two forms, as a normal display port and as
> > an
> > embedded display port.
> > 
> > Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> > Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> > [Bo-Chen: Fix reviewers' comment]
> > Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
> > ---
> >  .../display/mediatek/mediatek,dp.yaml         | 101
> > ++++++++++++++++++
> >  1 file changed, 101 insertions(+)
> >  create mode 100644
> > Documentation/devicetree/bindings/display/mediatek/mediatek,dp.yaml
> > 
> > diff --git
> > a/Documentation/devicetree/bindings/display/mediatek/mediatek,dp.ya
> > ml
> > b/Documentation/devicetree/bindings/display/mediatek/mediatek,dp.ya
> > ml
> > new file mode 100644
> > index 000000000000..10f50a0dcf49
> > --- /dev/null
> > +++
> > b/Documentation/devicetree/bindings/display/mediatek/mediatek,dp.ya
> > ml
> > @@ -0,0 +1,101 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: 
> > https://urldefense.com/v3/__http://devicetree.org/schemas/display/mediatek/mediatek,dp.yaml*__;Iw!!CTRNKA9wMg0ARbw!yqAl1KhfbHqHN7-5aeqhzqeOVhPU_Z5beko5q-y-s5pcfp1WL5oVGvY5UF4EfWm4PWjc5mjBwyBUMsr_RI45ipbhsw$
> >  
> > +$schema: 
> > https://urldefense.com/v3/__http://devicetree.org/meta-schemas/core.yaml*__;Iw!!CTRNKA9wMg0ARbw!yqAl1KhfbHqHN7-5aeqhzqeOVhPU_Z5beko5q-y-s5pcfp1WL5oVGvY5UF4EfWm4PWjc5mjBwyBUMsr_RI5WzYKENQ$
> >  
> > +
> > +title: MediaTek Display Port Controller
> > +
> > +maintainers:
> > +  - Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > +  - Jitao shi <jitao.shi@mediatek.com>
> > +
> > +description: |
> > +  Device tree bindings for the MediaTek display port and
> > +  embedded display port controller present on some MediaTek SoCs.
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - mediatek,mt8195-dp-tx
> > +      - mediatek,mt8195-edp-tx
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  nvmem-cells:
> > +    maxItems: 1
> > +    description: efuse data for display port calibration
> > +
> > +  nvmem-cell-names:
> > +    const: dp_calibration_data
> > +
> > +  power-domains:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  ports:
> > +    $ref: /schemas/graph.yaml#/properties/ports
> > +    properties:
> > +      port@0:
> > +        $ref: /schemas/graph.yaml#/properties/port
> > +        description: Input endpoint of the controller, usually
> > dp_intf
> > +
> > +      port@1:
> > +        $ref: /schemas/graph.yaml#/properties/port
> > +        description: Output endpoint of the controller
> > +
> > +    required:
> > +      - port@0
> > +      - port@1
> > +
> > +  max-lanes:
> > +    maxItems: 1
> > +    description: maximum number of lanes supported by the
> > hardware.
> 
> We already have a 'data-lanes' property defined in 
> 'video-interfaces.yaml' that can serve this purpose.
> 

Hello Rob,

Thanks for review.
From the description of video-interfaces.yaml, I think it's not quite
match what we need. We only need this value be one of "1,2,4".

Any other suggestion?

> > +
> > +  max-linkrate:
> > +    maxItems: 1
> > +    description: maximum link rate supported by the hardware and
> > unit is MHz.
> 
> Then use '-mhz' suffix on the property name. Then you don't need a
> type 
> (or maxItems).

OK, I will write like this:

  max-linkrate-mhz:
    enum: [ 1620, 2700, 5400, 8100 ]
    description: maximum link rate supported by the hardware.

BRs,
Bo-Chen