forked from Minki/linux
13b8a97a76
ASRC need to enable the spba clock, when sdma is using share peripheral script. In this case, there is two spba master port is used, if don't enable the clock, the spba bus will have arbitration issue, which may cause read/write wrong data from/to ASRC registers Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com> Acked-by: Nicolin Chen <nicoleotsuka@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
66 lines
2.4 KiB
Plaintext
66 lines
2.4 KiB
Plaintext
Freescale Asynchronous Sample Rate Converter (ASRC) Controller
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The Asynchronous Sample Rate Converter (ASRC) converts the sampling rate of a
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signal associated with an input clock into a signal associated with a different
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output clock. The driver currently works as a Front End of DPCM with other Back
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Ends Audio controller such as ESAI, SSI and SAI. It has three pairs to support
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three substreams within totally 10 channels.
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Required properties:
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- compatible : Contains "fsl,imx35-asrc" or "fsl,imx53-asrc".
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- reg : Offset and length of the register set for the device.
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- interrupts : Contains the spdif interrupt.
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- dmas : Generic dma devicetree binding as described in
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Documentation/devicetree/bindings/dma/dma.txt.
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- dma-names : Contains "rxa", "rxb", "rxc", "txa", "txb" and "txc".
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- clocks : Contains an entry for each entry in clock-names.
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- clock-names : Contains the following entries
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"mem" Peripheral access clock to access registers.
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"ipg" Peripheral clock to driver module.
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"asrck_<0-f>" Clock sources for input and output clock.
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"spba" The spba clock is required when ASRC is placed as a
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bus slave of the Shared Peripheral Bus and when two
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or more bus masters (CPU, DMA or DSP) try to access
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it. This property is optional depending on the SoC
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design.
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- big-endian : If this property is absent, the little endian mode
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will be in use as default. Otherwise, the big endian
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mode will be in use for all the device registers.
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- fsl,asrc-rate : Defines a mutual sample rate used by DPCM Back Ends.
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- fsl,asrc-width : Defines a mutual sample width used by DPCM Back Ends.
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Example:
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asrc: asrc@02034000 {
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compatible = "fsl,imx53-asrc";
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reg = <0x02034000 0x4000>;
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interrupts = <0 50 IRQ_TYPE_LEVEL_HIGH>;
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clocks = <&clks 107>, <&clks 107>, <&clks 0>,
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<&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
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<&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
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<&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
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<&clks 107>, <&clks 0>, <&clks 0>;
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clock-names = "mem", "ipg", "asrck0",
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"asrck_1", "asrck_2", "asrck_3", "asrck_4",
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"asrck_5", "asrck_6", "asrck_7", "asrck_8",
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"asrck_9", "asrck_a", "asrck_b", "asrck_c",
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"asrck_d", "asrck_e", "asrck_f";
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dmas = <&sdma 17 23 1>, <&sdma 18 23 1>, <&sdma 19 23 1>,
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<&sdma 20 23 1>, <&sdma 21 23 1>, <&sdma 22 23 1>;
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dma-names = "rxa", "rxb", "rxc",
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"txa", "txb", "txc";
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fsl,asrc-rate = <48000>;
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fsl,asrc-width = <16>;
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status = "okay";
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};
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