ASoC: nau8540: fix the record pop noise

When the record starts, the driver turns on MICBIAS and the voltage is
pulled up for an instant. If the receiver starts to capture the signal
between the instant, there is an pop noise in the stream beginning.
To avoid the pop noise, the driver makes a delay in the sequence.
After MICBIAS powered up, the driver waits 300 ms for the voltage
going down. Then turns on the ADC output, and sends signal to receiver.
The pop noise can be erased.

Signed-off-by: John Hsu <KCHSU0@nuvoton.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/nau8540.c b/sound/soc/codecs/nau8540.c
index 8246486a588dc6f255433d48c5a5903a1ddf04fa..9565f9a181a9e0b6cc708381f6e9a9f5ce7b5443 100644 (file)
--- a/sound/soc/codecs/nau8540.c
+++ b/sound/soc/codecs/nau8540.c
@@ -233,6 +233,28 @@ static SOC_ENUM_SINGLE_DECL(
 static const struct snd_kcontrol_new digital_ch1_mux =
        SOC_DAPM_ENUM("Digital CH1 Select", digital_ch1_enum);
 
+static int adc_power_control(struct snd_soc_dapm_widget *w,
+               struct snd_kcontrol *k, int  event)
+{
+       struct snd_soc_codec *codec = snd_soc_dapm_to_codec(w->dapm);
+       struct nau8540 *nau8540 = snd_soc_codec_get_drvdata(codec);
+
+       if (SND_SOC_DAPM_EVENT_ON(event)) {
+               msleep(300);
+               /* DO12 and DO34 pad output enable */
+               regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL1,
+                       NAU8540_I2S_DO12_TRI, 0);
+               regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL2,
+                       NAU8540_I2S_DO34_TRI, 0);
+       } else if (SND_SOC_DAPM_EVENT_OFF(event)) {
+               regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL1,
+                       NAU8540_I2S_DO12_TRI, NAU8540_I2S_DO12_TRI);
+               regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL2,
+                       NAU8540_I2S_DO34_TRI, NAU8540_I2S_DO34_TRI);
+       }
+       return 0;
+}
+
 static int aiftx_power_control(struct snd_soc_dapm_widget *w,
                struct snd_kcontrol *k, int  event)
 {
@@ -260,14 +282,18 @@ static const struct snd_soc_dapm_widget nau8540_dapm_widgets[] = {
        SND_SOC_DAPM_PGA("Frontend PGA3", NAU8540_REG_PWR, 14, 0, NULL, 0),
        SND_SOC_DAPM_PGA("Frontend PGA4", NAU8540_REG_PWR, 15, 0, NULL, 0),
 
-       SND_SOC_DAPM_ADC("ADC1", NULL,
-               NAU8540_REG_POWER_MANAGEMENT, 0, 0),
-       SND_SOC_DAPM_ADC("ADC2", NULL,
-               NAU8540_REG_POWER_MANAGEMENT, 1, 0),
-       SND_SOC_DAPM_ADC("ADC3", NULL,
-               NAU8540_REG_POWER_MANAGEMENT, 2, 0),
-       SND_SOC_DAPM_ADC("ADC4", NULL,
-               NAU8540_REG_POWER_MANAGEMENT, 3, 0),
+       SND_SOC_DAPM_ADC_E("ADC1", NULL,
+               NAU8540_REG_POWER_MANAGEMENT, 0, 0, adc_power_control,
+               SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
+       SND_SOC_DAPM_ADC_E("ADC2", NULL,
+               NAU8540_REG_POWER_MANAGEMENT, 1, 0, adc_power_control,
+               SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
+       SND_SOC_DAPM_ADC_E("ADC3", NULL,
+               NAU8540_REG_POWER_MANAGEMENT, 2, 0, adc_power_control,
+               SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
+       SND_SOC_DAPM_ADC_E("ADC4", NULL,
+               NAU8540_REG_POWER_MANAGEMENT, 3, 0, adc_power_control,
+               SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
 
        SND_SOC_DAPM_PGA("ADC CH1", NAU8540_REG_ANALOG_PWR, 0, 0, NULL, 0),
        SND_SOC_DAPM_PGA("ADC CH2", NAU8540_REG_ANALOG_PWR, 1, 0, NULL, 0),
@@ -737,6 +763,11 @@ static void nau8540_init_regs(struct nau8540 *nau8540)
        regmap_update_bits(regmap, NAU8540_REG_FEPGA2,
                NAU8540_FEPGA2_MODCH4_SHT | NAU8540_FEPGA2_MODCH3_SHT,
                NAU8540_FEPGA2_MODCH4_SHT | NAU8540_FEPGA2_MODCH3_SHT);
+       /* DO12 and DO34 pad output disable */
+       regmap_update_bits(regmap, NAU8540_REG_PCM_CTRL1,
+               NAU8540_I2S_DO12_TRI, NAU8540_I2S_DO12_TRI);
+       regmap_update_bits(regmap, NAU8540_REG_PCM_CTRL2,
+               NAU8540_I2S_DO34_TRI, NAU8540_I2S_DO34_TRI);
 }
 
 static int __maybe_unused nau8540_suspend(struct snd_soc_codec *codec)

diff --git a/sound/soc/codecs/nau8540.h b/sound/soc/codecs/nau8540.h
index 7083d4821ce4c9cb364a21b0212e4b0727112a87..dceb04b23c1961cb6320de1cac50548ce523dc9e 100644 (file)
--- a/sound/soc/codecs/nau8540.h
+++ b/sound/soc/codecs/nau8540.h
@@ -146,6 +146,7 @@
 #define NAU8540_I2S_DF_PCM_AB          0x3
 
 /* PCM_CTRL1 (0x11) */
+#define NAU8540_I2S_DO12_TRI           (0x1 << 15)
 #define NAU8540_I2S_LRC_DIV_SFT        12
 #define NAU8540_I2S_LRC_DIV_MASK       (0x3 << NAU8540_I2S_LRC_DIV_SFT)
 #define NAU8540_I2S_DO12_OE            (0x1 << 4)
@@ -156,6 +157,7 @@
 #define NAU8540_I2S_BLK_DIV_MASK       0x7
 
 /* PCM_CTRL1 (0x12) */
+#define NAU8540_I2S_DO34_TRI           (0x1 << 15)
 #define NAU8540_I2S_DO34_OE            (0x1 << 11)
 #define NAU8540_I2S_TSLOT_L_MASK       0x3ff