doc: dt: dma: add bindings for lpc1850-dmamux

Add device tree bindings documentation for the
lpc1850-dmamux DMA router.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/Documentation/devicetree/bindings/dma/lpc1850-dmamux.txt b/Documentation/devicetree/bindings/dma/lpc1850-dmamux.txt
new file mode 100644 (file)
index 0000000..87740ad
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+++ b/Documentation/devicetree/bindings/dma/lpc1850-dmamux.txt
@@ -0,0 +1,54 @@
+NXP LPC18xx/43xx DMA MUX (DMA request router)
+
+Required properties:
+- compatible:  "nxp,lpc1850-dmamux"
+- reg:         Memory map for accessing module
+- #dma-cells:  Should be set to <3>.
+               * 1st cell contain the master dma request signal
+               * 2nd cell contain the mux value (0-3) for the peripheral
+               * 3rd cell contain either 1 or 2 depending on the AHB
+                 master used.
+- dma-requests:        Number of DMA requests for the mux
+- dma-masters: phandle pointing to the DMA controller
+
+The DMA controller node need to have the following poroperties:
+- dma-requests:        Number of DMA requests the controller can handle
+
+Example:
+
+dmac: dma@40002000 {
+       compatible = "nxp,lpc1850-gpdma", "arm,pl080", "arm,primecell";
+       arm,primecell-periphid = <0x00041080>;
+       reg = <0x40002000 0x1000>;
+       interrupts = <2>;
+       clocks = <&ccu1 CLK_CPU_DMA>;
+       clock-names = "apb_pclk";
+       #dma-cells = <2>;
+       dma-channels = <8>;
+       dma-requests = <16>;
+       lli-bus-interface-ahb1;
+       lli-bus-interface-ahb2;
+       mem-bus-interface-ahb1;
+       mem-bus-interface-ahb2;
+       memcpy-burst-size = <256>;
+       memcpy-bus-width = <32>;
+};
+
+dmamux: dma-mux {
+       compatible = "nxp,lpc1850-dmamux";
+       #dma-cells = <3>;
+       dma-requests = <64>;
+       dma-masters = <&dmac>;
+};
+
+uart0: serial@40081000 {
+       compatible = "nxp,lpc1850-uart", "ns16550a";
+       reg = <0x40081000 0x1000>;
+       reg-shift = <2>;
+       interrupts = <24>;
+       clocks = <&ccu2 CLK_APB0_UART0>, <&ccu1 CLK_CPU_UART0>;
+       clock-names = "uartclk", "reg";
+       dmas = <&dmamux 1 1 2
+               &dmamux 2 1 2>;
+       dma-names = "tx", "rx";
+};