diff options
| author | Matthias Kaehlcke <mka@chromium.org> | 2018-02-16 09:53:12 -0800 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2018-02-19 12:16:41 +0000 |
| commit | 05c9b302eda71083840392d74ce62dd1e1f30621 (patch) | |
| tree | 623d9880bea900d9f98e0f2571fabe91826e6237 /Documentation | |
| parent | 6d6c3946d877adf1e73c6292f947bbb687452ed5 (diff) | |
ASoC: dmic: Add optional wakeup delay
On some systems a delay is needed after switching on the clocks, to allow
the output to stabilize and avoid a popping noise at the beginning of
the recording. Add the optional device tree property 'wakeup-delay-ms'
and apply the specified delay after enabling the mic. A blocking delay
can't be applied in dmic_daiops_trigger() since the function is called
in atomic context. Instead use a DAPM event handler to set the enable
GPIO and apply the delay in the handler.
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/sound/dmic.txt | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/sound/dmic.txt b/Documentation/devicetree/bindings/sound/dmic.txt index f7bf65611453..e957b4136716 100644 --- a/Documentation/devicetree/bindings/sound/dmic.txt +++ b/Documentation/devicetree/bindings/sound/dmic.txt @@ -8,6 +8,7 @@ Required properties: Optional properties: - dmicen-gpios: GPIO specifier for dmic to control start and stop - num-channels: Number of microphones on this DAI + - wakeup-delay-ms: Delay (in ms) after enabling the DMIC Example node: @@ -15,4 +16,5 @@ Example node: compatible = "dmic-codec"; dmicen-gpios = <&gpio4 3 GPIO_ACTIVE_HIGH>; num-channels = <1>; + wakeup-delay-ms <50>; }; |