ASoC: nau8821: Add delay control for ADC

Change the original fixed delay to the assignment from the property.
It will make it more flexible to different platforms to avoid pop
noise at the beginning of recording.

Signed-off-by: Seven Lee <wtli@nuvoton.com>
Link: https://lore.kernel.org/r/20240415070649.3496487-3-wtli@nuvoton.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: LeeWeiTse-seven

sound/soc/codecs/nau8821.c

@@ -511,7 +511,7 @@ static int nau8821_left_adc_event(struct snd_soc_dapm_widget *w,
 
 	switch (event) {
 	case SND_SOC_DAPM_POST_PMU:
-		msleep(125);
+		msleep(nau8821->adc_delay);
 		regmap_update_bits(nau8821->regmap, NAU8821_R01_ENA_CTRL,
 			NAU8821_EN_ADCL, NAU8821_EN_ADCL);
 		break;
@@ -535,7 +535,7 @@ static int nau8821_right_adc_event(struct snd_soc_dapm_widget *w,
 
 	switch (event) {
 	case SND_SOC_DAPM_POST_PMU:
-		msleep(125);
+		msleep(nau8821->adc_delay);
 		regmap_update_bits(nau8821->regmap, NAU8821_R01_ENA_CTRL,
 			NAU8821_EN_ADCR, NAU8821_EN_ADCR);
 		break;
@@ -1697,6 +1697,7 @@ static void nau8821_print_device_properties(struct nau8821 *nau8821)
 	dev_dbg(dev, "dmic-clk-threshold:       %d\n",
 		nau8821->dmic_clk_threshold);
 	dev_dbg(dev, "key_enable:       %d\n", nau8821->key_enable);
+	dev_dbg(dev, "adc-delay-ms:		%d\n", nau8821->adc_delay);
 }
 
 static int nau8821_read_device_properties(struct device *dev,
@@ -1742,6 +1743,12 @@ static int nau8821_read_device_properties(struct device *dev,
 		&nau8821->dmic_slew_rate);
 	if (ret)
 		nau8821->dmic_slew_rate = 0;
+	ret = device_property_read_u32(dev, "nuvoton,adc-delay-ms",
+		&nau8821->adc_delay);
+	if (ret)
+		nau8821->adc_delay = 125;
+	if (nau8821->adc_delay < 125 || nau8821->adc_delay > 500)
+		dev_warn(dev, "Please set the suitable delay time!\n");
 
 	return 0;
 }

sound/soc/codecs/nau8821.h

@@ -577,6 +577,7 @@ struct nau8821 {
 	int dmic_clk_threshold;
 	int dmic_slew_rate;
 	int key_enable;
+	int adc_delay;
 };
 
 int nau8821_enable_jack_detect(struct snd_soc_component *component,