From 1f1e60c9cdd573be271130e44a23efed48e0578d Mon Sep 17 00:00:00 2001 From: Zidan Wang 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 Signed-off-by: Mark Brown --- 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; }