On Fri, Jul 04, 2014 at 08:36:10AM +0100, Ludovic Desroches wrote: > Add bindings documentation for the new Atmel DMA controller (XDMAC) > introduced with SAMA5D4. > > Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx> > --- > .../devicetree/bindings/dma/atmel-xdma.txt | 39 ++++++++++++++++++++ > 1 file changed, 39 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/atmel-xdma.txt > > diff --git a/Documentation/devicetree/bindings/dma/atmel-xdma.txt b/Documentation/devicetree/bindings/dma/atmel-xdma.txt > new file mode 100644 > index 0000000..1e09fda > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/atmel-xdma.txt > @@ -0,0 +1,39 @@ > +* Atmel Extensible Direct Memory Access Controller (XDMAC) > + > +Required properties: > +- 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. Could you please move the description of the two cells in the dma-specifier here? It makes it far easier to read the binding. Cheers, Mark. > + > +Example: > + > +dma1: dma-controller@f0004000 { > + compatible = "atmel,sama5d4-dma"; > + reg = <0xf0004000 0x200>; > + interrupts = <50 4 0>; > + #dma-cells = <2>; > +}; > + > +DMA clients connected to the Atmel XDMA controller must use the format > +described in the dma.txt file, using a three-cell specifier for each channel: > +a phandle plus two integer cells. > +The two 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. Channel configuration register. Configurable fields are: > + - bit 30-24: PERID, peripheral identifier. > + > +Example: > + > +i2c2: i2c@f8024000 { > + compatible = "atmel,at91sam9x5-i2c"; > + reg = <0xf8024000 0x4000>; > + interrupts = <34 4 6>; > + dmas = <&dma0 0x00000001 0x06000000>, > + <&dma0 0x00000001 0x07000000>; > + dma-names = "tx", "rx"; > +}; > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html