[alsa-devel] [PATCH] ASoC: mediatek: mt6358: add delay after dmic clock on
Most dmics produce a high level when they receive clock. The difference between power-on and memory record time is about 10ms, but the dmic needs 50ms to output normal data.
This commit add 100ms delay after SoC output clock so that we can cut off the pop noise at the beginning.
Signed-off-by: Jiaxin Yu jiaxin.yu@mediatek.com --- Hi, This patch is based on for-next and discussed with tzungbi@google.com. --- --- sound/soc/codecs/mt6358.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/sound/soc/codecs/mt6358.c b/sound/soc/codecs/mt6358.c index c17250a..bb737fd 100644 --- a/sound/soc/codecs/mt6358.c +++ b/sound/soc/codecs/mt6358.c @@ -1730,6 +1730,10 @@ static int mt6358_dmic_enable(struct mt6358_priv *priv)
/* UL turn on */ regmap_write(priv->regmap, MT6358_AFE_UL_SRC_CON0_L, 0x0003); + + /* Prevent pop noise form dmic hw */ + msleep(100); + return 0; }
The patch
ASoC: mediatek: mt6358: add delay after dmic clock on
has been applied to the asoc tree at
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-5.4
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 ccb1fa21ef58a2ac15519bb878470762e967e8b3 Mon Sep 17 00:00:00 2001
From: Jiaxin Yu jiaxin.yu@mediatek.com Date: Mon, 5 Aug 2019 12:56:37 +0800 Subject: [PATCH] ASoC: mediatek: mt6358: add delay after dmic clock on
Most dmics produce a high level when they receive clock. The difference between power-on and memory record time is about 10ms, but the dmic needs 50ms to output normal data.
This commit add 100ms delay after SoC output clock so that we can cut off the pop noise at the beginning.
Signed-off-by: Jiaxin Yu jiaxin.yu@mediatek.com Link: https://lore.kernel.org/r/1564980997-11359-1-git-send-email-jiaxin.yu@mediat... Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/codecs/mt6358.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/sound/soc/codecs/mt6358.c b/sound/soc/codecs/mt6358.c index c17250aab2d0..bb737fd678cc 100644 --- a/sound/soc/codecs/mt6358.c +++ b/sound/soc/codecs/mt6358.c @@ -1730,6 +1730,10 @@ static int mt6358_dmic_enable(struct mt6358_priv *priv)
/* UL turn on */ regmap_write(priv->regmap, MT6358_AFE_UL_SRC_CON0_L, 0x0003); + + /* Prevent pop noise form dmic hw */ + msleep(100); + return 0; }
participants (2)
-
Jiaxin Yu -
Mark Brown