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

Rex-BC Chen rex-bc.chen at mediatek.com
Thu Jun 16 19:45:03 PDT 2022


On Thu, 2022-06-16 at 15:28 -0600, Rob Herring wrote:
> On Thu, Jun 16, 2022 at 09:22:16PM +0800, Rex-BC Chen wrote:
> > 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 at 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 at baylibre.com>
> > > > Signed-off-by: Guillaume Ranquet <granquet at baylibre.com>
> > > > [Bo-Chen: Fix reviewers' comment]
> > > > Signed-off-by: Bo-Chen Chen <rex-bc.chen at 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,d
> > > > p.ya
> > > > ml
> > > > b/Documentation/devicetree/bindings/display/mediatek/mediatek,d
> > > > p.ya
> > > > ml
> > > > new file mode 100644
> > > > index 000000000000..10f50a0dcf49
> > > > --- /dev/null
> > > > +++
> > > > b/Documentation/devicetree/bindings/display/mediatek/mediatek,d
> > > > p.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 at kernel.org>
> > > > +  - Jitao shi <jitao.shi at 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 at 0:
> > > > +        $ref: /schemas/graph.yaml#/properties/port
> > > > +        description: Input endpoint of the controller, usually
> > > > dp_intf
> > > > +
> > > > +      port at 1:
> > > > +        $ref: /schemas/graph.yaml#/properties/port
> > > > +        description: Output endpoint of the controller
> > > > +
> > > > +    required:
> > > > +      - port at 0
> > > > +      - port at 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".
> 
> data-lanes = <0>;
> data-lanes = <0 1>;
> data-lanes = <0 1 2 3>;
> 
> Limiting the number of lanes to something less than the max is
> exactly 
> how this property is used in addition to being able to show the
> mapping 
> of lanes.
> 
> Rob

Hello Rob,

I modify like this:
  data-lanes:
    $ref: /schemas/media/video-interfaces.yaml#
    description: |
      number of lanes supported by the hardware.
      The possible values:
      1     - For 1 lane enabled in IP.
      1 2   - For 2 lanes enabled in IP.
      1 2 4 - For 4 lanes enabled in IP.
    minItems: 1
    maxItems: 3

example:
data-lanes = <1 2 4>;

But I encounter errorr:
Documentation/devicetree/bindings/display/mediatek/mediatek,dp.example.
dtb: dp_tx at 1c600000: data-lanes: [[1, 2, 4]] is not of type 'object'
Documentation/devicetree/bindings/display/mediatek/mediatek,dp.example.
dtb: dp_tx at 1c600000: data-lanes: [[1, 2, 4]] is not of type 'object'

can you kindly give me some hint for this?

Thanks

BRs,
Bo-Chen




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