From: Gerhard Sittig <g...@denx.de>

introduce a device tree binding document for the MPC512x DMA controller

Signed-off-by: Gerhard Sittig <g...@denx.de>
[ a13xp0p0...@gmail.com: 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
+
+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
+
+Example:
+
+       sdhc@1500 {
+               compatible = "fsl,mpc5121-sdhc";
+               /* ... */
+               dmas = <&dma0 30>;
+               dma-names = "rx-tx";
+       };
-- 
1.8.4.2

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