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authorLudovic Desroches <ludovic.desroches@atmel.com>2013-04-19 09:11:18 +0000
committerVinod Koul <vinod.koul@intel.com>2013-04-30 14:17:41 +0530
commitbbe89c8e3d598129b728d1388c3ad9abe4e8e261 (patch)
treeb4654e214de37c86501ad83005c29a8419a97a3d /Documentation/devicetree
parente6a30fec08b421a59064437a7d990c70a80a7e7f (diff)
at_hdmac: move to generic DMA binding
Update at_hdmac driver to support generic DMA device tree binding. Devices can still request channel with dma_request_channel() then it doesn't break DMA for non DT boards. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'Documentation/devicetree')
-rw-r--r--Documentation/devicetree/bindings/dma/atmel-dma.txt35
1 files changed, 30 insertions, 5 deletions
diff --git a/Documentation/devicetree/bindings/dma/atmel-dma.txt b/Documentation/devicetree/bindings/dma/atmel-dma.txt
index 3c046ee6e8b5..c80e8a3402f0 100644
--- a/Documentation/devicetree/bindings/dma/atmel-dma.txt
+++ b/Documentation/devicetree/bindings/dma/atmel-dma.txt
@@ -1,14 +1,39 @@
* Atmel Direct Memory Access Controller (DMA)
Required properties:
-- compatible: Should be "atmel,<chip>-dma"
-- reg: Should contain DMA registers location and length
-- interrupts: Should contain DMA interrupt
+- compatible: Should be "atmel,<chip>-dma".
+- reg: Should contain DMA registers location and length.
+- interrupts: Should contain DMA interrupt.
+- #dma-cells: Must be <2>, used to represent the number of integer cells in
+the dmas property of client devices.
-Examples:
+Example:
-dma@ffffec00 {
+dma0: dma@ffffec00 {
compatible = "atmel,at91sam9g45-dma";
reg = <0xffffec00 0x200>;
interrupts = <21>;
+ #dma-cells = <2>;
+};
+
+DMA clients connected to the Atmel DMA controller must use the format
+described in the dma.txt file, using a three-cell specifier for each channel:
+a phandle plus two interger cells.
+The three cells in order are:
+
+1. A phandle pointing to the DMA controller.
+2. The memory interface (16 most significant bits), the peripheral interface
+(16 less significant bits).
+3. The peripheral identifier for the hardware handshaking interface. The
+identifier can be different for tx and rx.
+
+Example:
+
+i2c0@i2c@f8010000 {
+ compatible = "atmel,at91sam9x5-i2c";
+ reg = <0xf8010000 0x100>;
+ interrupts = <9 4 6>;
+ dmas = <&dma0 1 7>,
+ <&dma0 1 8>;
+ dma-names = "tx", "rx";
};