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author | Viorel Suman <viorel.suman@nxp.com> | 2019-01-22 14:14:27 +0300 |
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committer | Mark Brown <broonie@kernel.org> | 2019-03-26 17:07:43 +0300 |
commit | d0d9071b724123ebde89bdf6b52b86c3289abe85 (patch) | |
tree | 7d10f7a772748a1a81d1a0f79ce8824cdaa2a945 /Documentation/devicetree/bindings/sound/fsl,audmix.txt | |
parent | be1df61cf06efb355c90702e46b8d46f055acb4e (diff) | |
download | linux-d0d9071b724123ebde89bdf6b52b86c3289abe85.tar.xz |
ASoC: add fsl_audmix DT binding documentation
Add the DT binding documentation for NXP Audio Mixer
CPU DAI driver.
Signed-off-by: Viorel Suman <viorel.suman@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'Documentation/devicetree/bindings/sound/fsl,audmix.txt')
-rw-r--r-- | Documentation/devicetree/bindings/sound/fsl,audmix.txt | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/sound/fsl,audmix.txt b/Documentation/devicetree/bindings/sound/fsl,audmix.txt new file mode 100644 index 000000000000..45f807ec21a5 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/fsl,audmix.txt @@ -0,0 +1,54 @@ +NXP Audio Mixer (AUDMIX). + +The Audio Mixer is a on-chip functional module that allows mixing of two +audio streams into a single audio stream. Audio Mixer has two input serial +audio interfaces. These are driven by two Synchronous Audio interface +modules (SAI). Each input serial interface carries 8 audio channels in its +frame in TDM manner. Mixer mixes audio samples of corresponding channels +from two interfaces into a single sample. Before mixing, audio samples of +two inputs can be attenuated based on configuration. The output of the +Audio Mixer is also a serial audio interface. Like input interfaces it has +the same TDM frame format. This output is used to drive the serial DAC TDM +interface of audio codec and also sent to the external pins along with the +receive path of normal audio SAI module for readback by the CPU. + +The output of Audio Mixer can be selected from any of the three streams + - serial audio input 1 + - serial audio input 2 + - mixed audio + +Mixing operation is independent of audio sample rate but the two audio +input streams must have same audio sample rate with same number of channels +in TDM frame to be eligible for mixing. + +Device driver required properties: +================================= + - compatible : Compatible list, contains "fsl,imx8qm-audmix" + + - reg : Offset and length of the register set for the device. + + - clocks : Must contain an entry for each entry in clock-names. + + - clock-names : Must include the "ipg" for register access. + + - power-domains : Must contain the phandle to AUDMIX power domain node + + - dais : Must contain a list of phandles to AUDMIX connected + DAIs. The current implementation requires two phandles + to SAI interfaces to be provided, the first SAI in the + list being used to route the AUDMIX output. + + - model : Must contain machine driver name which will configure + and instantiate the appropriate audio card. + +Device driver configuration example: +====================================== + audmix: audmix@59840000 { + compatible = "fsl,imx8qm-audmix"; + reg = <0x0 0x59840000 0x0 0x10000>; + clocks = <&clk IMX8QXP_AUD_AUDMIX_IPG>; + clock-names = "ipg"; + power-domains = <&pd_audmix>; + dais = <&sai4>, <&sai5>; + model = "imx-audmix"; + }; |