1 files changed, 17 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/dma/sifive,fu540-c000-pdma.yaml b/Documentation/devicetree/bindings/dma/sifive,fu540-c000-pdma.yaml
index 47c46af25536..3271755787b4 100644
--- a/Documentation/devicetree/bindings/dma/sifive,fu540-c000-pdma.yaml
+++ b/Documentation/devicetree/bindings/dma/sifive,fu540-c000-pdma.yaml
@@ -28,7 +28,15 @@ allOf:
 properties:
   compatible:
     items:
-      - const: sifive,fu540-c000-pdma
+      - enum:
+          - sifive,fu540-c000-pdma
+      - const: sifive,pdma0
+    description:
+      Should be "sifive,<chip>-pdma" and "sifive,pdma<version>".
+      Supported compatible strings are -
+      "sifive,fu540-c000-pdma" for the SiFive PDMA v0 as integrated onto the
+      SiFive FU540 chip resp and "sifive,pdma0" for the SiFive PDMA v0 IP block
+      with no chip integration tweaks.
 
   reg:
     maxItems: 1
@@ -37,6 +45,12 @@ properties:
     minItems: 1
     maxItems: 8
 
+  dma-channels:
+    description: For backwards-compatibility, the default value is 4
+    minimum: 1
+    maximum: 4
+    default: 4
+
   '#dma-cells':
     const: 1
 
@@ -50,8 +64,9 @@ unevaluatedProperties: false
 examples:
   - |
     dma-controller@3000000 {
-      compatible = "sifive,fu540-c000-pdma";
+      compatible = "sifive,fu540-c000-pdma", "sifive,pdma0";
       reg = <0x3000000 0x8000>;
+      dma-channels = <4>;
       interrupts = <23>, <24>, <25>, <26>, <27>, <28>, <29>, <30>;
       #dma-cells = <1>;
     };