linux/Documentation/devicetree/bindings/sound/fsl,asrc.txt

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Freescale Asynchronous Sample Rate Converter (ASRC) Controller
The Asynchronous Sample Rate Converter (ASRC) converts the sampling rate of a
signal associated with an input clock into a signal associated with a different
output clock. The driver currently works as a Front End of DPCM with other Back
Ends Audio controller such as ESAI, SSI and SAI. It has three pairs to support
three substreams within totally 10 channels.
Required properties:
- compatible : Contains "fsl,imx35-asrc" or "fsl,imx53-asrc".
- reg : Offset and length of the register set for the device.
- interrupts : Contains the spdif interrupt.
- dmas : Generic dma devicetree binding as described in
Documentation/devicetree/bindings/dma/dma.txt.
- dma-names : Contains "rxa", "rxb", "rxc", "txa", "txb" and "txc".
- clocks : Contains an entry for each entry in clock-names.
- clock-names : Contains the following entries
"mem" Peripheral access clock to access registers.
"ipg" Peripheral clock to driver module.
"asrck_<0-f>" Clock sources for input and output clock.
- big-endian : If this property is absent, the little endian mode
will be in use as default. Otherwise, the big endian
mode will be in use for all the device registers.
- fsl,asrc-rate : Defines a mutual sample rate used by DPCM Back Ends.
- fsl,asrc-width : Defines a mutual sample width used by DPCM Back Ends.
Example:
asrc: asrc@02034000 {
compatible = "fsl,imx53-asrc";
reg = <0x02034000 0x4000>;
interrupts = <0 50 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clks 107>, <&clks 107>, <&clks 0>,
<&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
<&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
<&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
<&clks 107>, <&clks 0>, <&clks 0>;
clock-names = "mem", "ipg", "asrck0",
"asrck_1", "asrck_2", "asrck_3", "asrck_4",
"asrck_5", "asrck_6", "asrck_7", "asrck_8",
"asrck_9", "asrck_a", "asrck_b", "asrck_c",
"asrck_d", "asrck_e", "asrck_f";
dmas = <&sdma 17 23 1>, <&sdma 18 23 1>, <&sdma 19 23 1>,
<&sdma 20 23 1>, <&sdma 21 23 1>, <&sdma 22 23 1>;
dma-names = "rxa", "rxb", "rxc",
"txa", "txb", "txc";
fsl,asrc-rate = <48000>;
fsl,asrc-width = <16>;
status = "okay";
};