On 12/12/2017 3:10 AM, abhijeet.kumar@intel.com wrote:

From: Abhijeet Kumar abhijeet.kumar@intel.com

In skylake platform, we hear a loud pop noise(0 dB) at start of audio capture power up sequence. This patch removes the pop noise from the recording by adding a delay before enabling ADC.

Signed-off-by: Abhijeet Kumar abhijeet.kumar@intel.com

sound/soc/codecs/nau8825.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c index 714ce17da717..e853a6dfd33b 100644 --- a/sound/soc/codecs/nau8825.c +++ b/sound/soc/codecs/nau8825.c @@ -905,6 +905,7 @@ static int nau8825_adc_event(struct snd_soc_dapm_widget *w,

  switch (event) {
  case SND_SOC_DAPM_POST_PMU:

•         msleep(125);
          regmap_update_bits(nau8825->regmap, NAU8825_REG_ENA_CTRL,
                  NAU8825_ENABLE_ADC, NAU8825_ENABLE_ADC);
          break;
  

The solution is fine for me. It's verified in my device and indeed helps to reduce the capture pop noise. I think the little delay is acceptable.

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The patch

ASoC: nau8825: fix issue that pop noise when start capture

has been applied to the asoc tree at

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git

All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying to this mail.

Thanks, Mark

From d070f7c703ef26e3db613f24206823f916272fc6 Mon Sep 17 00:00:00 2001

From: Abhijeet Kumar abhijeet.kumar@intel.com Date: Tue, 12 Dec 2017 00:40:25 +0530 Subject: [PATCH] ASoC: nau8825: fix issue that pop noise when start capture

In skylake platform, we hear a loud pop noise(0 dB) at start of audio capture power up sequence. This patch removes the pop noise from the recording by adding a delay before enabling ADC.

Signed-off-by: Abhijeet Kumar abhijeet.kumar@intel.com Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/codecs/nau8825.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c index 714ce17da717..e853a6dfd33b 100644 --- a/sound/soc/codecs/nau8825.c +++ b/sound/soc/codecs/nau8825.c @@ -905,6 +905,7 @@ static int nau8825_adc_event(struct snd_soc_dapm_widget *w,

switch (event) { case SND_SOC_DAPM_POST_PMU: + msleep(125); regmap_update_bits(nau8825->regmap, NAU8825_REG_ENA_CTRL, NAU8825_ENABLE_ADC, NAU8825_ENABLE_ADC); break;