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+* BCM2835 DMA controller
+
+The BCM2835 DMA controller has 16 channels in total.
+Only the lower 13 channels have an associated IRQ.
+Some arbitrary channels are used by the firmware
+(1,3,6,7 in the current firmware version).
+The channels 0,2 and 3 have special functionality
+and should not be used by the driver.
+
+Required properties:
+- compatible: Should be "brcm,bcm2835-dma".
+- reg: Should contain DMA registers location and length.
+- interrupts: Should contain the DMA interrupts associated
+ to the DMA channels in ascending order.
+- #dma-cells: Must be <1>, the cell in the dmas property of the
+ client device represents the DREQ number.
+- brcm,dma-channel-mask: Bit mask representing the channels
+ not used by the firmware in ascending order,
+ i.e. first channel corresponds to LSB.
+
+Example:
+
+dma: dma@7e007000 {
+ compatible = "brcm,bcm2835-dma";
+ reg = <0x7e007000 0xf00>;
+ interrupts = <1 16>,
+ <1 17>,
+ <1 18>,
+ <1 19>,
+ <1 20>,
+ <1 21>,
+ <1 22>,
+ <1 23>,
+ <1 24>,
+ <1 25>,
+ <1 26>,
+ <1 27>,
+ <1 28>;
+
+ #dma-cells = <1>;
+ brcm,dma-channel-mask = <0x7f35>;
+};
+
+DMA clients connected to the BCM2835 DMA controller must use the format
+described in the dma.txt file, using a two-cell specifier for each channel.
+
+Example:
+
+bcm2835_i2s: i2s@7e203000 {
+ compatible = "brcm,bcm2835-i2s";
+ reg = < 0x7e203000 0x20>,
+ < 0x7e101098 0x02>;
+
+ dmas = <&dma 2>,
+ <&dma 3>;
+ dma-names = "tx", "rx";
+};

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