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authorPhilipp Zabel <p.zabel@pengutronix.de>2019-02-06 16:29:47 +0100
committerMark Brown <broonie@kernel.org>2019-02-06 15:46:06 +0000
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ASoC: ssm2602: Fix ADC powerup sequencing
According to the ssm2603 data sheet (control register sequencing), the digital core should be activated only after all necessary bits in the power register are enabled, and a delay determined by the decoupling capacitor on the VMID pin has passed. If the digital core is activated too early, or even before the ADC is powered up, audible artifacts appear at the beginning of the recorded signal. The digital core is also needed for playback, so when recording starts it may already be enabled. This means we cannot get the power sequence correct when we want to be able to start recording after playback. As a workaround put the MIC mute switch into the DAPM routes. This way we can keep the recording disabled until the MIC Bias has settled and thus get rid of audible artifacts. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> m.felsch@pengutronix.de: adapt commit message m.felsch@pengutronix.de: drop of configuration as mentioned by Mark: https://patchwork.kernel.org/patch/10407449/ Signed-off-by: Marco Felsch <m.felsch@pengutronix.de> Signed-off-by: Mark Brown <broonie@kernel.org>
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