On 6/8/2026 4:00 PM, Krzysztof Kozlowski wrote:

On Mon, Jun 08, 2026 at 10:32:33AM +0800, Joey Lu wrote:

quoted

The existing schema hard-codes the five-clock/three-reset/dual-port
topology of the DC8200 IP block, preventing reuse for single-output
variants such as the Verisilicon DCUltraLite used in the Nuvoton MA35D1
SoC.

Rework the schema so that variant-specific constraints are expressed via
allOf/if blocks:

- Add nuvoton,ma35d1-dcu to the SoC-specific compatible enum.  The
   generic verisilicon,dc fallback remains the driver-binding string.
- Relax the top-level clocks/resets definitions to minItems ranges so
   the base schema accepts both variants.
- Keep ports in the global required list and keep additionalProperties
   tightened to unevaluatedProperties.
- Add an allOf/if block for thead,th1520-dc8200: five-clock (core, axi,
   ahb, pix0, pix1), three-reset (core, axi, ahb).
- Add an allOf/if block for nuvoton,ma35d1-dcu: two-clock (core, pix0),
   one-reset (core).
- Fix a stray space in the port@0 description.
- Add a DT example for the Nuvoton MA35D1 DCU Lite using ports/port@0.

Signed-off-by: Joey Lu <redacted>
---
  .../bindings/display/verisilicon,dc.yaml      | 103 +++++++++++++++---
  1 file changed, 90 insertions(+), 13 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/verisilicon,dc.yaml b/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
index 9dc35ab973f2..db0260d874c5 100644
--- a/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
+++ b/Documentation/devicetree/bindings/display/verisilicon,dc.yaml

@@ -17,7 +17,8 @@ properties:
      items:
        - enum:
            - thead,th1520-dc8200
-      - const: verisilicon,dc # DC IPs have discoverable ID/revision registers
+          - nuvoton,ma35d1-dcu
+      - const: verisilicon,dc  # DC IPs have discoverable ID/revision registers

Why do you need to change indentation? Why introducing irrelevant
changes to the diff?

The extra space was introduced to satisfy `yamllint`'s "too few spaces 
before comment" warning, which requires two spaces before an inline `#`. 
Since this is an unrelated change that pollutes the diff, I will revert 
it to the original single-space form.

quoted

  
    reg:
      maxItems: 1

@@ -26,6 +27,7 @@ properties:
      maxItems: 1
  
    clocks:
+    minItems: 2
      items:
        - description: DC Core clock
        - description: DMA AXI bus clock

That's not true anymore. In such case the list should also be defined
per variant and here only min/maxItems.

Understood. I will remove the `items:` description list from the 
top-level `clocks:` and keep only `minItems`/`maxItems`. The per-variant 
items descriptions will be moved into the allOf/if blocks.

quoted

@@ -34,24 +36,19 @@ properties:
        - description: Pixel clock of output 1
  
    clock-names:
-    items:
-      - const: core
-      - const: axi
-      - const: ahb
-      - const: pix0
-      - const: pix1
+    minItems: 2
+    maxItems: 5
  
    resets:
+    minItems: 1
      items:
        - description: DC Core reset
        - description: DMA AXI bus reset
        - description: Configuration AHB bus reset
  
    reset-names:
-    items:
-      - const: core
-      - const: axi
-      - const: ahb

This stays, with minItems. Variants only need min/maxItems

Understood. I will restore the top-level `clock-names` and `reset-names` 
items lists and add `minItems` to each. The per-variant allOf blocks 
will only carry `minItems`/`maxItems`.

quoted

+    minItems: 1
+    maxItems: 3
  
    ports:
      $ref: /schemas/graph.yaml#/properties/ports

@@ -59,7 +56,7 @@ properties:
      properties:
        port@0:
          $ref: /schemas/graph.yaml#/properties/port
-        description: The first output channel , endpoint 0 should be
+        description: The first output channel, endpoint 0 should be
            used for DPI format output and endpoint 1 should be used
            for DP format output.
  

@@ -77,7 +74,60 @@ required:
    - clock-names
    - ports
  
-additionalProperties: false
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: thead,th1520-dc8200
+    then:
+      properties:
+        clocks:
+          minItems: 5
+          maxItems: 5
+
+        clock-names:
+          items:
+            - const: core
+            - const: axi
+            - const: ahb
+            - const: pix0
+            - const: pix1
+
+        resets:
+          minItems: 3
+          maxItems: 3
+
+        reset-names:

minItems: 3

Understood. I will add `minItems: 3` to `reset-names` in the 
thead,th1520-dc8200 block.

quoted

+          items:
+            - const: core
+            - const: axi
+            - const: ahb
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: nuvoton,ma35d1-dcu
+    then:
+      properties:
+        clocks:
+          minItems: 2
+          maxItems: 2
+
+        clock-names:
+          items:
+            - const: core
+            - const: pix0
+
+        resets:
+          maxItems: 1
+
+        reset-names:

maxItems: 1

Understood. I will add `maxItems: 1` to `reset-names` in the nuvoton block.

quoted

+          items:
+            - const: core
+
+unevaluatedProperties: false

Stop making random changes to the binding.

Best regards,
Krzysztof

Understood. I will revert to `additionalProperties: false` as in the 
original binding.

Many thanks!