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>

1 files changed, 45 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/dma/dma-common.yaml b/Documentation/devicetree/bindings/dma/dma-common.yaml
new file mode 100644
index 000000000000..0141af047820
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/dma-common.yaml
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/dma-common.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: DMA Engine Generic Binding
+
+maintainers:
+  - Vinod Koul <vkoul@kernel.org>
+
+description:
+  Generic binding to provide a way for a driver using DMA Engine to
+  retrieve the DMA request or channel information that goes from a
+  hardware device to a DMA controller.
+
+select: false
+
+properties:
+  "#dma-cells":
+    minimum: 1
+    # Should be enough
+    maximum: 255
+    description:
+      Used to provide DMA controller specific information.
+
+  dma-channel-masks:
+    $ref: /schemas/types.yaml#definitions/uint32
+    description:
+      Bitmask of available DMA channels in ascending order that are
+      not reserved by firmware and are available to the
+      kernel. i.e. first channel corresponds to LSB.
+
+  dma-channels:
+    $ref: /schemas/types.yaml#definitions/uint32
+    description:
+      Number of DMA channels supported by the controller.
+
+  dma-requests:
+    $ref: /schemas/types.yaml#definitions/uint32
+    description:
+      Number of DMA request signals supported by the controller.
+
+required:
+  - "#dma-cells"