[PATCH v3 4/6] dt-bindings: dma: arm,dma-350: Document the CIX Sky1 integration

[Jelly Jia <Jelly.Jia@cixtech.com>]

The CIX Sky1 DMA-350 integration is the same device with SoC glue around
it, so it is described by the arm,dma-350 node itself with an additional
"cix,sky1-dma350" compatible rather than by a separate wrapper node.

Extend the binding with the CIX compatible and the resources the
integration needs: a clock, which the CIX variant requires, an optional
reset, and an optional reserved memory region used when the controller
cannot reach all of system memory.

v2 -> v3:
- Drop the cix,irq-router property and its conditional: the Sky1
  interrupt gate it described is set up by the boot firmware and is not
  configured by Linux, so no property describes it.
- The CIX compatible now requires a clock.

Assisted-by: LLM checkpatch sparse dt_binding_check dtbs_check
Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
---
 .../devicetree/bindings/dma/arm,dma-350.yaml  | 26 ++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
index 429f682f15d8..4e0f9ffb0039 100644
--- a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
+++ b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
@@ -11,10 +11,22 @@ maintainers:
 
 allOf:
   - $ref: dma-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: cix,sky1-dma350
+    then:
+      required:
+        - clocks
 
 properties:
   compatible:
-    const: arm,dma-350
+    oneOf:
+      - const: arm,dma-350
+      - items:
+          - const: cix,sky1-dma350
+          - const: arm,dma-350
 
   reg:
     items:
@@ -36,6 +48,18 @@ properties:
     const: 1
     description: The cell is the trigger input number
 
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  memory-region:
+    maxItems: 1
+    description:
+      Reserved memory region used for DMA allocations when the controller
+      cannot reach all of system memory.
+
 required:
   - compatible
   - reg
-- 
2.54.0