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Diffstat (limited to 'Documentation/devicetree/bindings/dma/atmel-dma.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/dma/atmel-dma.txt | 35 |
1 files changed, 30 insertions, 5 deletions
diff --git a/Documentation/devicetree/bindings/dma/atmel-dma.txt b/Documentation/devicetree/bindings/dma/atmel-dma.txt index 3c046ee6e8b..c80e8a3402f 100644 --- a/Documentation/devicetree/bindings/dma/atmel-dma.txt +++ b/Documentation/devicetree/bindings/dma/atmel-dma.txt @@ -1,14 +1,39 @@ * Atmel Direct Memory Access Controller (DMA) Required properties: -- compatible: Should be "atmel,<chip>-dma" -- reg: Should contain DMA registers location and length -- interrupts: Should contain DMA interrupt +- compatible: Should be "atmel,<chip>-dma". +- reg: Should contain DMA registers location and length. +- interrupts: Should contain DMA interrupt. +- #dma-cells: Must be <2>, used to represent the number of integer cells in +the dmas property of client devices. -Examples: +Example: -dma@ffffec00 { +dma0: dma@ffffec00 { compatible = "atmel,at91sam9g45-dma"; reg = <0xffffec00 0x200>; interrupts = <21>; + #dma-cells = <2>; +}; + +DMA clients connected to the Atmel DMA controller must use the format +described in the dma.txt file, using a three-cell specifier for each channel: +a phandle plus two interger cells. +The three cells in order are: + +1. A phandle pointing to the DMA controller. +2. The memory interface (16 most significant bits), the peripheral interface +(16 less significant bits). +3. The peripheral identifier for the hardware handshaking interface. The +identifier can be different for tx and rx. + +Example: + +i2c0@i2c@f8010000 { + compatible = "atmel,at91sam9x5-i2c"; + reg = <0xf8010000 0x100>; + interrupts = <9 4 6>; + dmas = <&dma0 1 7>, + <&dma0 1 8>; + dma-names = "tx", "rx"; }; |