[PATCH v5 01/13] dt-bindings: display: st: add two new compatibles to LTDC device

Raphael Gallais-Pou posted 13 patches 1 month, 1 week ago
[PATCH v5 01/13] dt-bindings: display: st: add two new compatibles to LTDC device
Posted by Raphael Gallais-Pou 1 month, 1 week ago
The new STMicroelectronics SoC features a display controller similar to
the one used in previous SoCs.  Because there is additional registers,
and different mandatory clocks it is incompatible with existing IPs.  On
STM32MP251, the device only needs two clocks while on STM32MP255 it
needs four.

Add the new names to the list of compatible string and handle each
quirks accordingly.

Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
---
 .../devicetree/bindings/display/st,stm32-ltdc.yaml | 52 +++++++++++++++++++++-
 1 file changed, 50 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml b/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
index d6ea4d62a2cfae26353c9f20a326a4329fed3a2f..1233345a16307532ea08d3686d194b486f897ea9 100644
--- a/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
+++ b/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
@@ -12,7 +12,10 @@ maintainers:
 
 properties:
   compatible:
-    const: st,stm32-ltdc
+    enum:
+      - st,stm32-ltdc
+      - st,stm32mp251-ltdc
+      - st,stm32mp255-ltdc
 
   reg:
     maxItems: 1
@@ -24,11 +27,16 @@ properties:
     minItems: 1
 
   clocks:
-    maxItems: 1
+    minItems: 1
+    maxItems: 4
 
   clock-names:
     items:
       - const: lcd
+      - const: bus
+      - const: ref
+      - const: lvds
+    minItems: 1
 
   resets:
     maxItems: 1
@@ -51,6 +59,46 @@ required:
   - resets
   - port
 
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - st,stm32-ltdc
+    then:
+      properties:
+        clocks:
+          maxItems: 1
+        clock-names:
+          maxItems: 1
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - st,stm32mp251-ltdc
+    then:
+      properties:
+        clocks:
+          minItems: 2
+          maxItems: 2
+        clock-names:
+          minItems: 2
+          maxItems: 2
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - st,stm32mp255-ltdc
+    then:
+      properties:
+        clocks:
+          minItems: 4
+        clock-names:
+          minItems: 4
+
 additionalProperties: false
 
 examples:

-- 
2.25.1
Re: [PATCH v5 01/13] dt-bindings: display: st: add two new compatibles to LTDC device
Posted by Philippe CORNU 1 month ago

On 8/22/25 16:34, Raphael Gallais-Pou wrote:
> The new STMicroelectronics SoC features a display controller similar to
> the one used in previous SoCs.  Because there is additional registers,
> and different mandatory clocks it is incompatible with existing IPs.  On
> STM32MP251, the device only needs two clocks while on STM32MP255 it
> needs four.
> 
> Add the new names to the list of compatible string and handle each
> quirks accordingly.
> 
> Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
> ---
>   .../devicetree/bindings/display/st,stm32-ltdc.yaml | 52 +++++++++++++++++++++-
>   1 file changed, 50 insertions(+), 2 deletions(-)

Hi Raphael,

Acked-by: Philippe Cornu <philippe.cornu@foss.st.com>

note: you may add the v4 acked-by too on this patch.

Thanks
Philippe :-)
Re: [PATCH v5 01/13] dt-bindings: display: st: add two new compatibles to LTDC device
Posted by Krzysztof Kozlowski 1 month, 1 week ago
On Fri, Aug 22, 2025 at 04:34:10PM +0200, Raphael Gallais-Pou wrote:
> The new STMicroelectronics SoC features a display controller similar to
> the one used in previous SoCs.  Because there is additional registers,
> and different mandatory clocks it is incompatible with existing IPs.  On
> STM32MP251, the device only needs two clocks while on STM32MP255 it
> needs four.
> 
> Add the new names to the list of compatible string and handle each
> quirks accordingly.
> 
> Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
> ---
>  .../devicetree/bindings/display/st,stm32-ltdc.yaml | 52 +++++++++++++++++++++-
>  1 file changed, 50 insertions(+), 2 deletions(-)

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof