[alsa-devel] Applied "ASoC: cs42xx8: fix the noise in the right dac channel with mono playback" to the asoc tree

[Mark Brown]

The patch

   ASoC: cs42xx8: fix the noise in the right dac channel with mono playback

has been applied to the asoc tree at

   git://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 1f1e60c9cdd573be271130e44a23efed48e0578d Mon Sep 17 00:00:00 2001
From: Zidan Wang <zidan.wang at freescale.com>
Date: Tue, 24 Nov 2015 10:18:27 +0800
Subject: [PATCH] ASoC: cs42xx8: fix the noise in the right dac channel with
 mono playback

When playback mono wav with record in background, there will be some
nosie in the right dac channel. It seems that the ADC data has been
routed to the dac channel.

The cs42888 have 8 dac channels, it's appropriate to mute the unused
dac channels, and the noise will disappear.

Steps to reproduce this issue:
arecord -D hw:0,0 -f S16_LE -r 48000 -c 1 a.wav &
aplay -Dhw:0,0 audio48k16M.wav

Signed-off-by: Zidan Wang <zidan.wang at freescale.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/codecs/cs42xx8.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/cs42xx8.c b/sound/soc/codecs/cs42xx8.c
index d562e1b9a5d1..1179101b2b05 100644
--- a/sound/soc/codecs/cs42xx8.c
+++ b/sound/soc/codecs/cs42xx8.c
@@ -44,6 +44,7 @@ struct cs42xx8_priv {
 
 	bool slave_mode;
 	unsigned long sysclk;
+	u32 tx_channels;
 };
 
 /* -127.5dB to 0dB with step of 0.5dB */
@@ -257,6 +258,9 @@ static int cs42xx8_hw_params(struct snd_pcm_substream *substream,
 	u32 ratio = cs42xx8->sysclk / params_rate(params);
 	u32 i, fm, val, mask;
 
+	if (tx)
+		cs42xx8->tx_channels = params_channels(params);
+
 	for (i = 0; i < ARRAY_SIZE(cs42xx8_ratios); i++) {
 		if (cs42xx8_ratios[i].ratio == ratio)
 			break;
@@ -283,9 +287,11 @@ static int cs42xx8_digital_mute(struct snd_soc_dai *dai, int mute)
 {
 	struct snd_soc_codec *codec = dai->codec;
 	struct cs42xx8_priv *cs42xx8 = snd_soc_codec_get_drvdata(codec);
+	u8 dac_unmute = cs42xx8->tx_channels ?
+		        ~((0x1 << cs42xx8->tx_channels) - 1) : 0;
 
-	regmap_update_bits(cs42xx8->regmap, CS42XX8_DACMUTE,
-			   CS42XX8_DACMUTE_ALL, mute ? CS42XX8_DACMUTE_ALL : 0);
+	regmap_write(cs42xx8->regmap, CS42XX8_DACMUTE,
+		     mute ? CS42XX8_DACMUTE_ALL : dac_unmute);
 
 	return 0;
 }
-- 
2.7.0.rc3