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authorNicolin Chen <nicoleotsuka@gmail.com>2014-07-29 18:08:53 +0800
committerMark Brown <broonie@linaro.org>2014-07-29 19:22:49 +0100
commit3117bb3109dc223e186302f5dc8ce9ed04adca90 (patch)
tree35f65b00d2361c37d158f31a8ae1707975aaf1cc /Documentation
parent94b912e42829b25d97b6b1f2be66c6aa81ac125f (diff)
ASoC: fsl_asrc: Add ASRC ASoC CPU DAI and platform drivers
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 DAI links such as ESAI<->CS42888 and SSI<->WM8962 and SAI. It converts the original sample rate to a common rate supported by Back Ends for playback while converts the common rate of Back Ends to a desired rate for capture. It has 3 pairs to support three different substreams within totally 10 channels. Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com> Reviewed-by: Varka Bhadram <varkabhadram@gmail.com> Signed-off-by: Mark Brown <broonie@linaro.org>
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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";
+};