[alsa-devel] Applied "ASoC: mediatek: mt6358: add delay after dmic clock on" to the asoc tree

[Mark Brown]

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 at 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 at mediatek.com>
Link: https://lore.kernel.org/r/1564980997-11359-1-git-send-email-jiaxin.yu@mediatek.com
Signed-off-by: Mark Brown <broonie at 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;
 }
 
-- 
2.20.1