[PATCH v3 1/3] dt-bindings: dma: arm-dma350: document generic and combined IRQ topologies

[Jun Guo <jun.guo@cixtech.com>]

Update the DMA-350 DT binding to match the current driver behavior.

Allow both:
- "arm,dma-350" as the generic compatible, and
- "cix,sky1-dma-350", "arm,dma-350" for SoC-specific fallback usage.

Also document interrupt topology variants supported by hardware
integration:
- one combined interrupt for all channels, or
- one interrupt per channel (up to 8 channels).

This patch is Assisted-by: Cursor: GPT-5.3 Codex.

Signed-off-by: Jun Guo <jun.guo@cixtech.com>
Link: https://lore.kernel.org/r/20251216123026.3519923-2-jun.guo@cixtech.com
---
 .../devicetree/bindings/dma/arm,dma-350.yaml  | 31 +++++++++++++------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
index 429f682f15d8..3639ce0d5054 100644
--- a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
+++ b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
@@ -14,7 +14,11 @@ allOf:
 
 properties:
   compatible:
-    const: arm,dma-350
+    oneOf:
+      - const: arm,dma-350
+      - items:
+          - const: cix,sky1-dma-350
+          - const: arm,dma-350
 
   reg:
     items:
@@ -22,15 +26,22 @@ properties:
 
   interrupts:
     minItems: 1
-    items:
-      - description: Channel 0 interrupt
-      - description: Channel 1 interrupt
-      - description: Channel 2 interrupt
-      - description: Channel 3 interrupt
-      - description: Channel 4 interrupt
-      - description: Channel 5 interrupt
-      - description: Channel 6 interrupt
-      - description: Channel 7 interrupt
+    maxItems: 8
+    description: |
+      The DMA controller may be configured with separate interrupts for each channel,
+      or with a single combined interrupt for all channels, depending on the SoC integration.
+    oneOf:
+      - items:
+          - description: Channel 0 interrupt
+          - description: Channel 1 interrupt
+          - description: Channel 2 interrupt
+          - description: Channel 3 interrupt
+          - description: Channel 4 interrupt
+          - description: Channel 5 interrupt
+          - description: Channel 6 interrupt
+          - description: Channel 7 interrupt
+      - items:
+          - description: Combined interrupt shared by all channels
 
   "#dma-cells":
     const: 1
-- 
2.34.1