Hi Conor,

On 5/26/2026 8:54 AM, Damon Ding wrote:

Hi Conor,

On 5/26/2026 12:54 AM, Conor Dooley wrote:

quoted

On Mon, May 25, 2026 at 08:53:22PM +0800, Damon Ding wrote:

quoted

RK3588 eDP controller requires HCLK_VO1 to access the VO1 GRF
registers and enable the video datapath.

Previously, the clock was enabled implicitly via the 'rockchip,vo-grf'
phandle reference, which allowed the eDP to work without explicitly
managing the hclk_vo1 clock. However, this is not safe or explicit.

To make the clock dependency explicit, enforce per-SoC clock-names
requirements:
  - RK3288: 2 clocks (dp, pclk)
  - RK3399: 3 clocks (dp, pclk, grf)
  - RK3588: 3 clocks (dp, pclk, hclk)

Do not reuse the 'grf' clock name for RK3588 because it represents
a different clock with distinct control logic:
- The 'grf' clock is only for GRF register access and is toggled
   dynamically during register access.
- The 'hclk' clock controls both GRF access and video datapath
   gating, and must remain enabled during probe.

Fixes: f855146263b1 ("dt-bindings: display: rockchip: analogix-dp: 
Add support for RK3588")
Signed-off-by: Damon Ding <redacted>

---

Changes in v4:
- Modify the commit msg.

Changes in v5:
- Enforce the correct third clock name on a per-compatible basis.
- Modify the commit msg simultaneously.

Changes in v6:
- Expand more detail commit msg about using hclk instead of grf clock.

Changes in v7:
- List all valid clock names at the top level, and constrain the clock
   count for each platform with minItems/maxItems in allOf.

Changes in v8:
- Fix indentation to 10 for enum in clock-names property.
---
  .../rockchip/rockchip,analogix-dp.yaml        | 34 ++++++++++++++++++-
  1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/display/rockchip/ 

rockchip,analogix-dp.yaml b/Documentation/devicetree/bindings/ 
display/rockchip/rockchip,analogix-dp.yaml
index d99b23b88cc5..a1ab7a77bdd3 100644

--- a/Documentation/devicetree/bindings/display/rockchip/ 

rockchip,analogix-dp.yaml

+++ b/Documentation/devicetree/bindings/display/rockchip/ 

rockchip,analogix-dp.yaml

@@ -26,7 +26,9 @@ properties:

      items:
        - const: dp
        - const: pclk
-      - const: grf
+      - enum:
+          - grf
+          - hclk
    power-domains:
      maxItems: 1

@@ -60,6 +62,32 @@ required:

  allOf:
    - $ref: /schemas/display/bridge/analogix,dp.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - rockchip,rk3288-dp
+    then:
+      properties:
+        clocks:
+          maxItems: 2
+        clock-names:
+          maxItems: 2
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - rockchip,rk3399-edp
+    then:
+      properties:
+        clocks:
+          minItems: 3
+        clock-names:
+          minItems: 3

If you go back to v6, you'll see that I never asked you to remove the
explict clock-names from here or below. Only the one from the 3288
section. The minItems was an addition, not a replacement.

pw-bot: changes-requested

Sorry for the misunderstanding. I will restore the explicit clock-names 
definitions and fix this in next version.

Sorry to bother you. I attempted to place the explicit clock-names under 
minItems:

diff --git 

a/Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml 
b/Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml
index a1ab7a77bdd3..ef03edf52de8 100644
--- 
a/Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml
+++ 
b/Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml

@@ -87,6 +87,10 @@ allOf:
            minItems: 3
          clock-names:
            minItems: 3
+          items:
+            - const: dp
+            - const: pclk
+            - const: grf

    - if:
        properties:

@@ -100,6 +104,10 @@ allOf:
            minItems: 3
          clock-names:
            minItems: 3
+          items:
+            - const: dp
+            - const: pclk
+            - const: hclk
          resets:
            minItems: 2
          reset-names:

make dt_binding_check 
DT_SCHEMA_FILES=Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml

Then the following errors occurred:

   SCHEMA  Documentation/devicetree/bindings/processed-schema.json
   CHKDT   ./Documentation/devicetree/bindings
/home/ding/drm-misc/Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml: 
allOf:2:then:properties:clock-names: 'oneOf' conditional failed, one 
must be fixed:
         False schema does not allow 3
         [{'const': 'dp'}, {'const': 'pclk'}, {'const': 'grf'}] is too long
         [{'const': 'dp'}, {'const': 'pclk'}, {'const': 'grf'}] is too short
         1 was expected
         3 is greater than the maximum of 2
         hint: "minItems" is only needed if less than the "items" list 
length
         from schema $id: http://devicetree.org/meta-schemas/items.yaml
/home/ding/drm-misc/Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.yaml: 
allOf:3:then:properties:clock-names: 'oneOf' conditional failed, one 
must be fixed:
         False schema does not allow 3
         [{'const': 'dp'}, {'const': 'pclk'}, {'const': 'hclk'}] is too long
         [{'const': 'dp'}, {'const': 'pclk'}, {'const': 'hclk'}] is too 
short
         1 was expected
         3 is greater than the maximum of 2
         hint: "minItems" is only needed if less than the "items" list 
length
         from schema $id: http://devicetree.org/meta-schemas/items.yaml
   LINT    ./Documentation/devicetree/bindings
   DTEX 
Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.example.dts
   DTC [C] 
Documentation/devicetree/bindings/display/rockchip/rockchip,analogix-dp.example.dtb

Neither keeping only minItems nor only the explicit clock-names causes 
any errors. Would it be a better idea to keep just the explicit 
clock-names here?

Best regards,
Damon

quoted

quoted

+
    - if:
        properties:
          compatible:

@@ -68,6 +96,10 @@ allOf:

                - rockchip,rk3588-edp
      then:
        properties:
+        clocks:
+          minItems: 3
+        clock-names:
+          minItems: 3
          resets:
            minItems: 2
          reset-names:
-- 
2.34.1