Hello Mark, thanks for your reply! 2014-06-18 17:37 GMT+04:00 Mark Rutland <mark.rutland@xxxxxxx>: > On Wed, Jun 18, 2014 at 11:48:10AM +0100, Alexander Popov wrote: >> Introduce a device tree binding document for the MPC512x DMA controller >> >> Signed-off-by: Alexander Popov <a13xp0p0v88@xxxxxxxxx> >> --- >> .../devicetree/bindings/dma/mpc512x-dma.txt | 31 ++++++++++++++++++++++ >> 1 file changed, 31 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..95e2ca0 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/dma/mpc512x-dma.txt >> @@ -0,0 +1,31 @@ >> +* Freescale MPC512x and MPC8308 DMA Controller >> + >> +The DMA controller in Freescale MPC512x and MPC8308 SoCs can move >> +blocks of memory contents between memory and peripherals or >> +from memory to memory. >> + >> +Refer to "Generic DMA Controller and DMA request bindings" in >> +the dma/dma.txt file for a more detailed description of binding. >> + >> +Required properties: >> +- compatible: should be "fsl,mpc5121-dma" or "fsl,mpc8308-dma"; >> +- reg: should contain the DMA controller registers location and length; >> +- interrupt for the DMA controller: syntax of interrupt client node >> + is described in interrupt-controller/interrupts.txt file. >> + >> +Optional properties: >> +- #dma-cells: the length of the DMA specifier, must be <1>. >> + Each channel of this DMA controller has a peripheral request line, >> + the assignment is fixed in hardware. This one cell >> + in dmas property of a client device represents the channel number. > > Surely this is required to be able to refer to DMA channels on the > device? Excuse me, I didn't understand your question. Do you inquire about the reason of making #dma-cells an optional property? It's optional because device tree based lookup support is made optional (part 3/3). Best regards, Alexander -- 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
