ASoC: cs42l42: Allow time for HP/ADC to power-up after enable

After enabling the HP or ADC by writing the corresponding PDN=0,
it takes around 20 milliseconds for it to power up and the midrail
supply to be stable. Add this wait into a DAPM widget callback.

If HP and ADC are both powering up in a DAPM sequence, there's no
need to do the wait twice. The widget will perform one wait in the
POST_PMU if there was a PRE_PMU for one or both.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20211015133619.4698-13-rf@opensource.cirrus.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/cs42l42.c

@@ -435,10 +435,36 @@ static const struct snd_kcontrol_new cs42l42_snd_controls[] = {
 				0x3f, 1, mixer_tlv)
 };
 
+static int cs42l42_hp_adc_ev(struct snd_soc_dapm_widget *w,
+			     struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
+	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
+
+	switch (event) {
+	case SND_SOC_DAPM_PRE_PMU:
+		cs42l42->hp_adc_up_pending = true;
+		break;
+	case SND_SOC_DAPM_POST_PMU:
+		/* Only need one delay if HP and ADC are both powering-up */
+		if (cs42l42->hp_adc_up_pending) {
+			usleep_range(CS42L42_HP_ADC_EN_TIME_US,
+				     CS42L42_HP_ADC_EN_TIME_US + 1000);
+			cs42l42->hp_adc_up_pending = false;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
 static const struct snd_soc_dapm_widget cs42l42_dapm_widgets[] = {
 	/* Playback Path */
 	SND_SOC_DAPM_OUTPUT("HP"),
-	SND_SOC_DAPM_DAC("DAC", NULL, CS42L42_PWR_CTL1, CS42L42_HP_PDN_SHIFT, 1),
+	SND_SOC_DAPM_DAC_E("DAC", NULL, CS42L42_PWR_CTL1, CS42L42_HP_PDN_SHIFT, 1,
+			   cs42l42_hp_adc_ev, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMU),
 	SND_SOC_DAPM_MIXER("MIXER", CS42L42_PWR_CTL1, CS42L42_MIXER_PDN_SHIFT, 1, NULL, 0),
 	SND_SOC_DAPM_AIF_IN("SDIN1", NULL, 0, SND_SOC_NOPM, 0, 0),
 	SND_SOC_DAPM_AIF_IN("SDIN2", NULL, 1, SND_SOC_NOPM, 0, 0),
@@ -448,7 +474,8 @@ static const struct snd_soc_dapm_widget cs42l42_dapm_widgets[] = {
 
 	/* Capture Path */
 	SND_SOC_DAPM_INPUT("HS"),
-	SND_SOC_DAPM_ADC("ADC", NULL, CS42L42_PWR_CTL1, CS42L42_ADC_PDN_SHIFT, 1),
+	SND_SOC_DAPM_ADC_E("ADC", NULL, CS42L42_PWR_CTL1, CS42L42_ADC_PDN_SHIFT, 1,
+			   cs42l42_hp_adc_ev, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMU),
 	SND_SOC_DAPM_AIF_OUT("SDOUT1", NULL, 0, CS42L42_ASP_TX_CH_EN, CS42L42_ASP_TX0_CH1_SHIFT, 0),
 	SND_SOC_DAPM_AIF_OUT("SDOUT2", NULL, 1, CS42L42_ASP_TX_CH_EN, CS42L42_ASP_TX0_CH2_SHIFT, 0),
 

sound/soc/codecs/cs42l42.h

@@ -761,6 +761,7 @@
 #define CS42L42_CLOCK_SWITCH_DELAY_US 150
 #define CS42L42_PLL_LOCK_POLL_US	250
 #define CS42L42_PLL_LOCK_TIMEOUT_US	1250
+#define CS42L42_HP_ADC_EN_TIME_US	20000
 
 static const char *const cs42l42_supply_names[CS42L42_NUM_SUPPLIES] = {
 	"VA",
@@ -794,6 +795,7 @@ struct  cs42l42_private {
 	u8 hs_bias_ramp_time;
 	u8 hs_bias_sense_en;
 	u8 stream_use;
+	bool hp_adc_up_pending;
 };
 
 #endif /* __CS42L42_H__ */