MLK-16784-2 documentation: sound: add documentation for PDM

Add documentation for micfil IP.

Signed-off-by: Cosmin-Gabriel Samoila <cosmin.samoila@nxp.com>

1 files changed, 38 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sound/fsl,micfil.txt b/Documentation/devicetree/bindings/sound/fsl,micfil.txt
new file mode 100644
index 000000000000..d7830af62062
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+++ b/Documentation/devicetree/bindings/sound/fsl,micfil.txt
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+Freescale MICFIL PDM Interface (MICFIL).
+
+The MICFIL digital interface provides a 16-bit audio signal from a PDM
+microphone bitstream in a configurable output sampling rate.
+
+Required properties:
+
+  - compatible		: Compatible list, contains "fsl,imx8mm-micfil"
+
+  - reg			: Offset and length of the register set for the device.
+
+  - interrupts		: Contains the micfil interrupts.
+
+  - clocks		: Must contain an entry for each entry in clock-names.
+
+  - clock-names		: Must include the "ipg_clk" for register access and
+			  "ipg_clk_app" for internal micfil clock.
+
+  - dmas		: Generic dma devicetree binding as described in
+			  Documentation/devicetree/bindings/dma/dma.txt.
+
+  - dma-names		: One "rx" dma must be configured.
+
+Example:
+micfil: micfil@30080000 {
+	compatible = "fsl,imx8mm-micfil";
+	reg = <0x0 0x30080000 0x0 0x10000>;
+	interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>,
+		     <GIC_SPI 45 IRQ_TYPE_LEVEL_HIGH>,
+		     <GIC_SPI 109 IRQ_TYPE_LEVEL_HIGH>,
+		     <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&clk IMX8MM_CLK_PDM_IPG>,
+		 <&clk IMX8MM_CLK_PDM_ROOT>;
+	clock-names = "ipg_clk", "ipg_clk_app";
+	dmas = <&sdma2 24 26 0x80000000>;
+	dma-names = "rx";
+	status = "disabled";
+};