dt-bindings: sound: lpass-cpu: Document DAI subnodes

The lpass-cpu driver now allows configuring the MI2S SD lines
by defining subnodes for one of the DAIs.

Document this in the device tree bindings.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20200425184657.121991-1-stephan@gerhold.net
Signed-off-by: Mark Brown <broonie@kernel.org>
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Stephan Gerhold 2020-04-25 20:46:56 +02:00 committed by Mark Brown
parent dbab677f32
commit d5797ede08
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@ -30,6 +30,8 @@ Required properties:
- reg : Must contain an address for each entry in reg-names.
- reg-names : A list which must include the following entries:
* "lpass-lpaif"
- #address-cells : Must be 1
- #size-cells : Must be 0
@ -37,6 +39,20 @@ Optional properties:
- qcom,adsp : Phandle for the audio DSP node
By default, the driver uses up to 4 MI2S SD lines, for a total of 8 channels.
The SD lines to use can be configured by adding subnodes for each of the DAIs.
Required properties for each DAI (represented by a subnode):
- reg : Must be one of the DAI IDs
(usually part of dt-bindings header)
- qcom,playback-sd-lines: List of serial data lines to use for playback
Each SD line should be represented by a number from 0-3.
- qcom,capture-sd-lines : List of serial data lines to use for capture
Each SD line should be represented by a number from 0-3.
Note that adding a subnode changes the default to "no lines configured",
so both playback and capture lines should be configured when a subnode is added.
Example:
lpass@28100000 {
@ -51,4 +67,13 @@ lpass@28100000 {
reg = <0x28100000 0x10000>;
reg-names = "lpass-lpaif";
qcom,adsp = <&adsp>;
#address-cells = <1>;
#size-cells = <0>;
/* Optional to set different MI2S SD lines */
dai@3 {
reg = <MI2S_QUATERNARY>;
qcom,playback-sd-lines = <0 1>;
};
};