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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
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parentInitial commit. (diff)
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Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+* 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.
+- #dma-cells: Must be <2>, used to represent the number of integer cells in
+the dmas property of client devices.
+
+Example:
+
+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 integer 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. Parameters for the at91 DMA configuration register which are device
+dependent:
+ - bit 7-0: peripheral identifier for the hardware handshaking interface. The
+ identifier can be different for tx and rx.
+ - bit 11-8: FIFO configuration. 0 for half FIFO, 1 for ALAP, 2 for ASAP.
+
+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";
+};