[PATCH 1/8] dt-bindings: dma: marvell,mmp-dma: Add SpacemiT PDMA compatibility

[Guodong Xu <guodong@riscstar.com>]

Add "spacemit,pdma-1.0" compatible string to support SpacemiT PDMA
controller in the Marvell MMP DMA device tree bindings. This enables:

- Support for SpacemiT PDMA controller configuration
- New optional properties for platform-specific integration:
  * clocks: Clock controller for the DMA
  * resets: Reset controller for the DMA

Also, add explicit #dma-cells property definition to avoid
"make dtbs_check W=3" warnings about unevaluated properties.

The #dma-cells property is defined as 2 cells to maintain compatibility
with existing ARM device trees. The first cell specifies the DMA request
line number, while the second cell is currently unused by the driver but
required for backward compatibility with PXA device tree files.

Signed-off-by: Guodong Xu <guodong@riscstar.com>
---
 .../bindings/dma/marvell,mmp-dma.yaml           | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/dma/marvell,mmp-dma.yaml b/Documentation/devicetree/bindings/dma/marvell,mmp-dma.yaml
index d447d5207be0..e117a81414bd 100644
--- a/Documentation/devicetree/bindings/dma/marvell,mmp-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/marvell,mmp-dma.yaml
@@ -18,6 +18,7 @@ properties:
       - marvell,pdma-1.0
       - marvell,adma-1.0
       - marvell,pxa910-squ
+      - spacemit,pdma-1.0
 
   reg:
     maxItems: 1
@@ -32,6 +33,21 @@ properties:
       A phandle to the SRAM pool
     $ref: /schemas/types.yaml#/definitions/phandle
 
+  clocks:
+    description: Clock for the controller
+    maxItems: 1
+
+  resets:
+    description: Reset controller for the DMA controller
+    maxItems: 1
+
+  '#dma-cells':
+    const: 2
+    description:
+      The first cell contains the DMA request number for the peripheral
+      device. The second cell is currently unused but must be present for
+      backward compatibility.
+
   '#dma-channels':
     deprecated: true
 
@@ -52,6 +68,7 @@ allOf:
           contains:
             enum:
               - marvell,pdma-1.0
+              - spacemit,pdma-1.0
     then:
       properties:
         asram: false
-- 
2.43.0