ASoC: rouleur: Change hph and ear gain according to soc capacity

Register to power supply framework to get soc capacity.
Reduce ear and hph gain for reduced voltage to optimize
power consumption. Also set LD22 voltage to lower value
for low SoC.

Change-Id: I94de9341b8c7307128d3cd41c7398c31d57fa685
Signed-off-by: Vatsal Bucha <vbucha@codeaurora.org>

asoc/codecs/rouleur/internal.h

@@ -85,6 +85,9 @@ struct rouleur_priv {
 	struct mutex main_bias_lock;
 	bool dev_up;
 	bool usbc_hs_status;
+	struct notifier_block psy_nb;
+	struct work_struct soc_eval_work;
+	bool low_soc;
 };
 
 struct rouleur_micbias_setting {
@@ -131,6 +134,7 @@ enum {
 	WCD_BOLERO_EVT_IMPED_FALSE,	/* for imped false */
 	WCD_BOLERO_EVT_RX_COMPANDER_SOFT_RST,
 	WCD_BOLERO_EVT_BCS_CLK_OFF,
+	WCD_BOLERO_EVT_RX_PA_GAIN_UPDATE, /* To reduce PA gain for low SoC */
 };
 
 enum {

asoc/codecs/rouleur/rouleur.c

@@ -26,6 +26,7 @@
 #include <asoc/msm-cdc-pinctrl.h>
 #include <dt-bindings/sound/audio-codec-port-types.h>
 #include <asoc/msm-cdc-supply.h>
+#include <linux/power_supply.h>
 
 #define DRV_NAME "rouleur_codec"
 
@@ -35,6 +36,8 @@
 #define ROULEUR_VERSION_ENTRY_SIZE 32
 
 #define NUM_ATTEMPTS 5
+#define SOC_THRESHOLD_LEVEL 25
+#define LOW_SOC_MBIAS_REG_MIN_VOLTAGE 2850000
 
 enum {
 	CODEC_TX = 0,
@@ -2000,6 +2003,107 @@ done:
 	return rc;
 }
 
+static int rouleur_battery_supply_cb(struct notifier_block *nb,
+			unsigned long event, void *data)
+{
+	struct power_supply *psy = data;
+	struct rouleur_priv *rouleur =
+		container_of(nb, struct rouleur_priv, psy_nb);
+
+	if (strcmp(psy->desc->name, "battery"))
+		return NOTIFY_OK;
+	queue_work(system_freezable_wq, &rouleur->soc_eval_work);
+
+	return NOTIFY_OK;
+}
+
+static int rouleur_read_battery_soc(struct rouleur_priv *rouleur, int *soc_val)
+{
+	static struct power_supply *batt_psy;
+	union power_supply_propval ret = {0,};
+	int err = 0;
+
+	*soc_val = 100;
+	if (!batt_psy)
+		batt_psy = power_supply_get_by_name("battery");
+	if (batt_psy) {
+		err = power_supply_get_property(batt_psy,
+				POWER_SUPPLY_PROP_CAPACITY, &ret);
+		if (err) {
+			pr_err("%s: battery SoC read error:%d\n",
+				__func__, err);
+			return err;
+		}
+		*soc_val = ret.intval;
+	}
+	pr_debug("%s: soc:%d\n", __func__, *soc_val);
+
+	return err;
+}
+
+static void rouleur_evaluate_soc(struct work_struct *work)
+{
+	struct rouleur_priv *rouleur =
+		container_of(work, struct rouleur_priv, soc_eval_work);
+	int soc_val = 0, ret = 0;
+	struct rouleur_pdata *pdata = NULL;
+
+	pdata = dev_get_platdata(rouleur->dev);
+	if (!pdata) {
+		dev_err(rouleur->dev, "%s: pdata is NULL\n", __func__);
+		return;
+	}
+
+	if (rouleur_read_battery_soc(rouleur, &soc_val) < 0) {
+		dev_err(rouleur->dev, "%s unable to read battery SoC\n",
+			__func__);
+		return;
+	}
+
+	if (soc_val < SOC_THRESHOLD_LEVEL) {
+		dev_dbg(rouleur->dev,
+			"%s battery SoC less than threshold soc_val = %d\n",
+			__func__, soc_val);
+		/* Reduce PA Gain by 6DB for low SoC */
+		if (rouleur->update_wcd_event)
+			rouleur->update_wcd_event(rouleur->handle,
+					WCD_BOLERO_EVT_RX_PA_GAIN_UPDATE,
+					true);
+		rouleur->low_soc = true;
+		ret = msm_cdc_set_supply_min_voltage(rouleur->dev,
+						 rouleur->supplies,
+						 pdata->regulator,
+						 pdata->num_supplies,
+						 "cdc-vdd-mic-bias",
+						 LOW_SOC_MBIAS_REG_MIN_VOLTAGE,
+						 true);
+		if (ret < 0)
+			dev_err(rouleur->dev,
+				"%s unable to set mbias min voltage\n",
+				__func__);
+	} else {
+		if (rouleur->low_soc == true) {
+			/* Reset PA Gain to default for normal SoC */
+			if (rouleur->update_wcd_event)
+				rouleur->update_wcd_event(rouleur->handle,
+					WCD_BOLERO_EVT_RX_PA_GAIN_UPDATE,
+					false);
+			ret = msm_cdc_set_supply_min_voltage(rouleur->dev,
+						rouleur->supplies,
+						pdata->regulator,
+						pdata->num_supplies,
+						"cdc-vdd-mic-bias",
+						LOW_SOC_MBIAS_REG_MIN_VOLTAGE,
+						false);
+			if (ret < 0)
+				dev_err(rouleur->dev,
+					"%s unable to set mbias min voltage\n",
+					__func__);
+			rouleur->low_soc = false;
+		}
+	}
+}
+
 static int rouleur_soc_codec_probe(struct snd_soc_component *component)
 {
 	struct rouleur_priv *rouleur = snd_soc_component_get_drvdata(component);
@@ -2070,7 +2174,16 @@ static int rouleur_soc_codec_probe(struct snd_soc_component *component)
 			return ret;
 		}
 	}
+	rouleur->low_soc = false;
 	rouleur->dev_up = true;
+	/* Register notifier to change gain based on state of charge */
+	INIT_WORK(&rouleur->soc_eval_work, rouleur_evaluate_soc);
+	rouleur->psy_nb.notifier_call = rouleur_battery_supply_cb;
+	if (power_supply_reg_notifier(&rouleur->psy_nb) < 0)
+		dev_dbg(rouleur->dev,
+			"%s: could not register pwr supply notifier\n",
+			__func__);
+	queue_work(system_freezable_wq, &rouleur->soc_eval_work);
 done:
 	return ret;
 }