1 This file has been moved to dma-controller.yam !! 1 * Generic DMA Controller and DMA request bindings
>> 2
>> 3 Generic binding to provide a way for a driver using DMA Engine to retrieve the
>> 4 DMA request or channel information that goes from a hardware device to a DMA
>> 5 controller.
>> 6
>> 7
>> 8 * DMA controller
>> 9
>> 10 Required property:
>> 11 - #dma-cells: Must be at least 1. Used to provide DMA controller
>> 12 specific information. See DMA client binding below for
>> 13 more details.
>> 14
>> 15 Optional properties:
>> 16 - dma-channels: Number of DMA channels supported by the controller.
>> 17 - dma-requests: Number of DMA requests signals supported by the
>> 18 controller.
>> 19
>> 20 Example:
>> 21
>> 22 dma: dma@48000000 {
>> 23 compatible = "ti,omap-sdma";
>> 24 reg = <0x48000000 0x1000>;
>> 25 interrupts = <0 12 0x4
>> 26 0 13 0x4
>> 27 0 14 0x4
>> 28 0 15 0x4>;
>> 29 #dma-cells = <1>;
>> 30 dma-channels = <32>;
>> 31 dma-requests = <127>;
>> 32 };
>> 33
>> 34
>> 35 * DMA client
>> 36
>> 37 Client drivers should specify the DMA property using a phandle to the controller
>> 38 followed by DMA controller specific data.
>> 39
>> 40 Required property:
>> 41 - dmas: List of one or more DMA specifiers, each consisting of
>> 42 - A phandle pointing to DMA controller node
>> 43 - A number of integer cells, as determined by the
>> 44 #dma-cells property in the node referenced by phandle
>> 45 containing DMA controller specific information. This
>> 46 typically contains a DMA request line number or a
>> 47 channel number, but can contain any data that is used
>> 48 required for configuring a channel.
>> 49 - dma-names: Contains one identifier string for each DMA specifier in
>> 50 the dmas property. The specific strings that can be used
>> 51 are defined in the binding of the DMA client device.
>> 52 Multiple DMA specifiers can be used to represent
>> 53 alternatives and in this case the dma-names for those
>> 54 DMA specifiers must be identical (see examples).
>> 55
>> 56 Examples:
>> 57
>> 58 1. A device with one DMA read channel, one DMA write channel:
>> 59
>> 60 i2c1: i2c@1 {
>> 61 ...
>> 62 dmas = <&dma 2 /* read channel */
>> 63 &dma 3>; /* write channel */
>> 64 dma-names = "rx", "tx";
>> 65 ...
>> 66 };
>> 67
>> 68 2. A single read-write channel with three alternative DMA controllers:
>> 69
>> 70 dmas = <&dma1 5
>> 71 &dma2 7
>> 72 &dma3 2>;
>> 73 dma-names = "rx-tx", "rx-tx", "rx-tx";
>> 74
>> 75 3. A device with three channels, one of which has two alternatives:
>> 76
>> 77 dmas = <&dma1 2 /* read channel */
>> 78 &dma1 3 /* write channel */
>> 79 &dma2 0 /* error read */
>> 80 &dma3 0>; /* alternative error read */
>> 81 dma-names = "rx", "tx", "error", "error";
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