Add a property to list DAPM endpoints which mark paths between these endpoints should not be disabled when system enters in suspend state.
LPA means low power audio case. For example on asymmetric multiprocessor, there are Cortex-A core and Cortex-M core, Linux is running on Cortex-A core, RTOS or other OS is running on Cortex-M core. The audio hardware devices can be controlled by Cortex-M. LPA can be explained as a mechanism that Cortex-A allocates a large buffer and fill audio data, then Cortex-A can enter into suspend for the purpose of power saving. Cortex-M continues to play the sound during suspend phase of Cortex-A. LPA requires some audio paths still enabled when Cortex-A enters into suspend.
Signed-off-by: Chancel Liu chancel.liu@nxp.com --- .../bindings/sound/sound-card-common.yaml | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/Documentation/devicetree/bindings/sound/sound-card-common.yaml b/Documentation/devicetree/bindings/sound/sound-card-common.yaml index 3a941177f684..f43147c78651 100644 --- a/Documentation/devicetree/bindings/sound/sound-card-common.yaml +++ b/Documentation/devicetree/bindings/sound/sound-card-common.yaml @@ -17,6 +17,20 @@ properties: pair of strings, the first being the connection's sink, the second being the connection's source.
+ lpa-widgets: + $ref: /schemas/types.yaml#/definitions/non-unique-string-array + description: | + A list of DAPM endpoints which mark paths between these endpoints should + not be disabled when system enters in suspend state. LPA means low power + audio case. For example on asymmetric multiprocessor, there are Cortex-A + core and Cortex-M core, Linux is running on Cortex-A core, RTOS or other + OS is running on Cortex-M core. The audio hardware devices can be + controlled by Cortex-M. LPA can be explained as a mechanism that Cortex-A + allocates a large buffer and fill audio data, then Cortex-A can enter + into suspend for the purpose of power saving. Cortex-M continues to play + the sound during suspend phase of Cortex-A. LPA requires some audio paths + still enabled when Cortex-A enters into suspend. + model: $ref: /schemas/types.yaml#/definitions/string description: User specified audio sound card name