dt-bindings: dmaengine: Add YAML schemas for the generic DMA bindings

The DMA controllers and consumers have a bunch of generic properties that
are needed in a device tree. Add a YAML schemas for those.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>

Link: https://lore.kernel.org/r/20190720092607.31095-1-maxime.ripard@bootlin.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
diff --git a/Documentation/devicetree/bindings/dma/dma-controller.yaml b/Documentation/devicetree/bindings/dma/dma-controller.yaml
new file mode 100644
index 0000000..c39f6de
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/dma-controller.yaml
@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/dma-controller.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: DMA Controller Generic Binding
+
+maintainers:
+  - Vinod Koul <vkoul@kernel.org>
+
+allOf:
+  - $ref: "dma-common.yaml#"
+
+# Everything else is described in the common file
+properties:
+  $nodename:
+    pattern: "^dma-controller(@.*)?$"
+
+examples:
+  - |
+    dma: dma-controller@48000000 {
+        compatible = "ti,omap-sdma";
+        reg = <0x48000000 0x1000>;
+        interrupts = <0 12 0x4
+                      0 13 0x4
+                      0 14 0x4
+                      0 15 0x4>;
+        #dma-cells = <1>;
+        dma-channels = <32>;
+        dma-requests = <127>;
+        dma-channel-mask = <0xfffe>;
+    };
+
+...