On Wed, Mar 12, 2014 at 11:47:54AM +0000, Alexander Popov wrote: > From: Gerhard Sittig <gsi@xxxxxxx> > > introduce a device tree binding document for the MPC512x DMA controller > > Signed-off-by: Gerhard Sittig <gsi@xxxxxxx> > [ a13xp0p0v88@xxxxxxxxx: turn this into a separate patch ] > --- > .../devicetree/bindings/dma/mpc512x-dma.txt | 55 ++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/mpc512x-dma.txt > > diff --git a/Documentation/devicetree/bindings/dma/mpc512x-dma.txt b/Documentation/devicetree/bindings/dma/mpc512x-dma.txt > new file mode 100644 > index 0000000..a4867d5 > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/mpc512x-dma.txt > @@ -0,0 +1,55 @@ > +* Freescale MPC512x DMA Controller > + > +The DMA controller in the Freescale MPC512x SoC can move blocks of > +memory contents between memory and peripherals or memory to memory. > + > +Refer to the "Generic DMA Controller and DMA request bindings" description > +in the dma.txt file for a more detailled discussion of the binding. The > +MPC512x DMA engine binding follows the common scheme, but doesn't provide > +support for the optional channels and requests counters (those values are > +derived from the detected hardware features) and has a fixed client > +specifier length of 1 integer cell (the value is the DMA channel, since > +the DMA controller uses a fixed assignment of request lines per channel). > + > + > +DMA controller node properties: > + > +Required properties: > +- compatible: should be "fsl,mpc5121-dma" > +- reg: address and size of the DMA controller's register set > +- interrupts: interrupt spec for the DMA controller > + > +Optional properties: > +- #dma-cells: must be <1>, describes the number of integer cells > + needed to specify the 'dmas' property in client nodes, > + strongly recommended since common client helper code > + uses this property Describe what you expect this cell to contain, not the #dma-cells binding in general. The DMA bindings already cover that. What are valid value that clients may use, and what do they mean? > + > +Example: > + > + dma0: dma@14000 { > + compatible = "fsl,mpc5121-dma"; > + reg = <0x14000 0x1800>; > + interrupts = <65 0x8>; > + #dma-cells = <1>; > + }; > + > + > +Client node properties: > + > +Required properties: > +- dmas: list of DMA specifiers, consisting each of a handle > + for the DMA controller and integer cells to specify > + the channel used within the DMA controller > +- dma-names: list of identifier strings for the DMA specifiers, > + client device driver code uses these strings to > + have DMA channels looked up at the controller List the exact names you expect, or the dma-names property is useless. Thanks, Mark. > + > +Example: > + > + sdhc@1500 { > + compatible = "fsl,mpc5121-sdhc"; > + /* ... */ > + dmas = <&dma0 30>; > + dma-names = "rx-tx"; > + }; > -- > 1.8.4.2 > > -- > 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