[PATCH v2] dt-bindings: dma: fsl,imx-dma: Document the DMA clocks

[Fabio Estevam <festevam@gmail.com>]

From: Fabio Estevam <festevam@denx.de>

Document the IPG and AHB clocks that are needed by the DMA hardware
as required properties.

It is not possible to have DMA functional without the DMA clocks
being turned on.

Signed-off-by: Fabio Estevam <festevam@denx.de>
---
Changes since v1:
- Mark clock and clock-names as required properties (Conor).

 .../devicetree/bindings/dma/fsl,imx-dma.yaml       | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/Documentation/devicetree/bindings/dma/fsl,imx-dma.yaml b/Documentation/devicetree/bindings/dma/fsl,imx-dma.yaml
index 902a11f65be2..75957f9fb58b 100644
--- a/Documentation/devicetree/bindings/dma/fsl,imx-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/fsl,imx-dma.yaml
@@ -28,6 +28,14 @@ properties:
       - description: DMA Error interrupt
     minItems: 1
 
+  clocks:
+    maxItems: 2
+
+  clock-names:
+    items:
+      - const: ipg
+      - const: ahb
+
   "#dma-cells":
     const: 1
 
@@ -42,15 +50,21 @@ required:
   - reg
   - interrupts
   - "#dma-cells"
+  - clocks
+  - clock-names
 
 additionalProperties: false
 
 examples:
   - |
+    #include <dt-bindings/clock/imx27-clock.h>
+
     dma-controller@10001000 {
       compatible = "fsl,imx27-dma";
       reg = <0x10001000 0x1000>;
       interrupts = <32 33>;
       #dma-cells = <1>;
       dma-channels = <16>;
+      clocks = <&clks IMX27_CLK_DMA_IPG_GATE>, <&clks IMX27_CLK_DMA_AHB_GATE>;
+      clock-names = "ipg", "ahb";
     };
-- 
2.34.1