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| author | Stephan Gerhold | 2021-12-14 15:20:47 +0100 |
|---|---|---|
| committer | Mark Brown | 2021-12-23 18:34:24 +0000 |
| commit | 37a49da9a7d5ac1f7128000de42ff222da46ba7a (patch) | |
| tree | 67a0be6a6d7dcce84e4e156287dc901b179fb96b | |
| parent | 3d4641a42ccf1593b3f3a474ee7541727acbb8e0 (diff) | |
ASoC: dt-bindings: qcom: sm8250: Document "pin-switches" and "widgets"
Some sound card setups might require extra pin switches to allow
turning off certain audio components. There are two real examples for
this in smartphones/tablets based on MSM8916:
1. Analog speaker amplifiers connected to headphone outputs.
The MSM8916 analog codec does not have a separate "Line Out" port
so some devices have an analog speaker amplifier connected to one
of the headphone outputs. A pin switch is necessary to allow
playback on headphones without also activating the speaker.
2. External speaker codec also used as earpiece.
Some smartphones have two front-facing (stereo) speakers that can
be also configured to act as an earpiece during voice calls. A pin
switch is needed to allow disabling the second speaker during
voice calls.
There are existing bindings that allow setting up such pin switches in
simple-card.yaml. Document the same for Qcom sound cards.
One variant of example 1 above is added to the examples in the DT
schema: There is an analog speaker amplifier connected to the HPH_R
(right headphone channel) output. Adding a "Speaker" pin switch and
widget allows turning off the speaker when audio should be only played
via the connected headphones.
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211214142049.20422-3-stephan@gerhold.net
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | Documentation/devicetree/bindings/sound/qcom,sm8250.yaml | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml b/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml index e50964c54bb9..4bfda04b4608 100644 --- a/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml +++ b/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml @@ -39,6 +39,14 @@ properties: $ref: /schemas/types.yaml#/definitions/string description: User visible long sound card name + pin-switches: + description: List of widget names for which pin switches should be created. + $ref: /schemas/types.yaml#/definitions/string-array + + widgets: + description: User specified audio sound widgets. + $ref: /schemas/types.yaml#/definitions/non-unique-string-array + # Only valid for some compatibles (see allOf if below) reg: true reg-names: true @@ -251,7 +259,15 @@ examples: reg-names = "mic-iomux", "spkr-iomux"; model = "msm8916"; + widgets = + "Speaker", "Speaker", + "Headphone", "Headphones"; + pin-switches = "Speaker"; audio-routing = + "Speaker", "Speaker Amp OUT", + "Speaker Amp IN", "HPH_R", + "Headphones", "HPH_L", + "Headphones", "HPH_R", "AMIC1", "MIC BIAS Internal1", "AMIC2", "MIC BIAS Internal2", "AMIC3", "MIC BIAS Internal3"; |