Re: [PATCH 01/12] dt-bindings: display: st: add new compatible to LTDC device

On 7/25/25 21:49, Rob Herring wrote:

On Fri, Jul 25, 2025 at 12:03:53PM +0200, Raphael Gallais-Pou wrote:

quoted

The new STMicroelectronics SoC features a display controller similar to
the one used in previous SoCs.  Because there is additional registers,
it is incompatible with existing IPs.

Add the new name to the list of compatible string.

Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
---
 .../devicetree/bindings/display/st,stm32-ltdc.yaml | 37 +++++++++++++++++++---
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml b/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
index d6ea4d62a2cfae26353c9f20a326a4329fed3a2f..546f57cb7a402b82e868aa05f874c65b8da19444 100644
--- a/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
+++ b/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml

@@ -12,7 +12,9 @@ maintainers:
 
 properties:
   compatible:
-    const: st,stm32-ltdc
+    enum:
+      - st,stm32-ltdc
+      - st,stm32mp25-ltdc
 
   reg:
     maxItems: 1

@@ -24,11 +26,12 @@ properties:
     minItems: 1
 
   clocks:
-    maxItems: 1
+    minItems: 1
+    maxItems: 4
 
   clock-names:
-    items:
-      - const: lcd
+    minItems: 1
+    maxItems: 4
 
   resets:
     maxItems: 1

@@ -51,6 +54,32 @@ required:
   - resets
   - port
 
+if:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - st,stm32-ltdc
+then:
+  properties:
+    clocks:
+      maxItems: 1
+    clock-names:
+      maxItems: 1
+      items:
+        - const: lcd
+else:
+  properties:
+    clocks:
+      maxItems: 4
+    clock-names:
+      maxItems: 4
+      items:
+      - const: bus
+      - const: lcd

Why can't 'lcd' be 1st so you aren't changing positions? Keep the items 
list at the top level and just use minItems/maxItems in the if/then 
schemas.

Hi Rob,

I've set the name order to match the stm32mp255.dtsi device-tree, so that it
does not confuse anybody regarding which clock goes with.

Your comment is taken into account for the upcoming version.

Thanks,
Raphaël

quoted

+      - const: ref
+      - const: lvds
+
 additionalProperties: false
 
 examples:

-- 
2.25.1