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+* Generic DMA Controller and DMA request bindings
+
+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.
+
+
+* DMA controller
+
+Required property:
+- #dma-cells: Must be at least 1. Used to provide DMA controller
+ specific information. See DMA client binding below for
+ more details.
+
+Optional properties:
+- dma-channels: Number of DMA channels supported by the controller.
+- dma-requests: Number of DMA requests signals supported by the
+ controller.
+
+Example:
+
+ dma: dma@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 client
+
+Client drivers should specify the DMA property using a phandle to the controller
+followed by DMA controller specific data.
+
+Required property:
+- dmas: List of one or more DMA specifiers, each consisting of
+ - A phandle pointing to DMA controller node
+ - A number of integer cells, as determined by the
+ #dma-cells property in the node referenced by phandle
+ containing DMA controller specific information. This
+ typically contains a DMA request line number or a
+ channel number, but can contain any data that is used
+ required for configuring a channel.
+- dma-names: Contains one identifier string for each DMA specifier in
+ the dmas property. The specific strings that can be used
+ are defined in the binding of the DMA client device.
+ Multiple DMA specifiers can be used to represent
+ alternatives and in this case the dma-names for those
+ DMA specifiers must be identical (see examples).
+
+Examples:
+
+1. A device with one DMA read channel, one DMA write channel:
+
+ i2c1: i2c@1 {
+ ...
+ dmas = <&dma 2 /* read channel */
+ &dma 3>; /* write channel */
+ dma-names = "rx", "tx";
+ ...
+ };
+
+2. A single read-write channel with three alternative DMA controllers:
+
+ dmas = <&dma1 5
+ &dma2 7
+ &dma3 2>;
+ dma-names = "rx-tx", "rx-tx", "rx-tx";
+
+3. A device with three channels, one of which has two alternatives:
+
+ dmas = <&dma1 2 /* read channel */
+ &dma1 3 /* write channel */
+ &dma2 0 /* error read */
+ &dma3 0>; /* alternative error read */
+ dma-names = "rx", "tx", "error", "error";