Documentation/devicetree/bindings/dma/fsl-imx-dma.txt

   1 * Freescale Direct Memory Access (DMA) Controller for i.MX
   2
   3 This document will only describe differences to the generic DMA Controller and
   4 DMA request bindings as described in dma/dma.txt .
   5
   6 * DMA controller
   7
   8 Required properties:
   9 - compatible : Should be "fsl,<chip>-dma". chip can be imx1, imx21 or imx27
  10 - reg : Should contain DMA registers location and length
  11 - interrupts : First item should be DMA interrupt, second one is optional and
  12     should contain DMA Error interrupt
  13 - #dma-cells : Has to be 1. imx-dma does not support anything else.
  14
  15 Optional properties:
  16 - #dma-channels : Number of DMA channels supported. Should be 16.
  17 - #dma-requests : Number of DMA requests supported.
  18
  19 Example:
  20
  21         dma: dma@10001000 {
  22                 compatible = "fsl,imx27-dma";
  23                 reg = <0x10001000 0x1000>;
  24                 interrupts = <32 33>;
  25                 #dma-cells = <1>;
  26                 #dma-channels = <16>;
  27         };
  28
  29
  30 * DMA client
  31
  32 Clients have to specify the DMA requests with phandles in a list.
  33
  34 Required properties:
  35 - dmas: List of one or more DMA request specifiers. One DMA request specifier
  36     consists of a phandle to the DMA controller followed by the integer
  37     specifying the request line.
  38 - dma-names: List of string identifiers for the DMA requests. For the correct
  39     names, have a look at the specific client driver.
  40
  41 Example:
  42
  43         sdhci1: sdhci@10013000 {
  44                 ...
  45                 dmas = <&dma 7>;
  46                 dma-names = "rx-tx";
  47                 ...
  48         };