spi: dt-bindings: stm32: update bindings with SPI Rx DMA-MDMA chaining

Add MDMA channel, and new sram property which are mandatory to enable
SPI Rx DMA-MDMA chaining.

Signed-off-by: Clément Le Goffic <clement.legoffic@foss.st.com>
Link: https://patch.msgid.link/20250616-spi-upstream-v1-3-7e8593f3f75d@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: clegoffic

Documentation/devicetree/bindings/spi/st,stm32-spi.yaml

@@ -18,6 +18,38 @@ maintainers:
 
 allOf:
   - $ref: spi-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: st,stm32f4-spi
+
+    then:
+      properties:
+        st,spi-midi-ns: false
+        sram: false
+        dmas:
+          maxItems: 2
+        dma-names:
+          items:
+            - const: rx
+            - const: tx
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: st,stm32mp25-spi
+
+    then:
+      properties:
+        sram: false
+        dmas:
+          maxItems: 2
+        dma-names:
+          items:
+            - const: rx
+            - const: tx
 
 properties:
   compatible:
@@ -41,16 +73,28 @@ properties:
 
   dmas:
     description: |
-      DMA specifiers for tx and rx dma. DMA fifo mode must be used. See
-      the STM32 DMA controllers bindings Documentation/devicetree/bindings/dma/stm32/*.yaml.
+      DMA specifiers for tx and rx channels. DMA fifo mode must be used. See
+      the STM32 DMA bindings Documentation/devicetree/bindings/dma/stm32/st,*dma.yaml
+    minItems: 2
     items:
       - description: rx DMA channel
       - description: tx DMA channel
+      - description: rxm2m MDMA channel
 
   dma-names:
+    minItems: 2
     items:
       - const: rx
       - const: tx
+      - const: rxm2m
+
+  sram:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: |
+      Phandles to a reserved SRAM region which is used as temporary
+      storage memory between DMA and MDMA engines.
+      The region should be defined as child node of the AHB SRAM node
+      as per the generic bindings in Documentation/devicetree/bindings/sram/sram.yaml
 
   access-controllers:
     minItems: 1