fsl-imx-dma.txt 1.3 KB

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