power: bq2419x: add thermal support for charging voltage

The maximum charging voltage depends on the battery temperature.
Add DT porperty and mechanims to set different charging voltage
for different temperature.

bug 1472161

Change-Id: Ia6fa3ee84cfd1f9ad8359e8249ffb268330f90cf
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/379575
GVS: Gerrit_Virtual_Submit

3 files changed, 66 insertions, 3 deletions

diff --git a/Documentation/devicetree/bindings/power/bq2419x-charger.txt b/Documentation/devicetree/bindings/power/bq2419x-charger.txt
index b47812c66097..71816ce693e7 100644
--- a/Documentation/devicetree/bindings/power/bq2419x-charger.txt
+++ b/Documentation/devicetree/bindings/power/bq2419x-charger.txt
@@ -27,12 +27,19 @@ Optional properties:
                             will be disabled.
 - rtc-alarm-time          : Time setting in seconds for the rtc alarm timer
                             which wakes the board up for charging after shutdown.
+
 - ti,temp-range: List of temperatures in degC for thermal profiling.
 - ti,charge-current-limit: List of fast charging current limit in mA for
 		thermal profiling.
-	The value is provided as
+		this property is deprecated. Instead use the property name as
+		ti,charge-thermal-current-limit.
+- ti,charge-thermal-voltage-limit: List of charging voltage limit in mV for
+		thermal profiling.
+
+	The values are provided as
 	ti,temp-range = <15 60>;
 	ti,charge-current-limit = <2048 5200>;
+	ti,charge-thermal-voltage-limit = <4200 4300>;
 
 	This will set chargign current limit to
 		2048 for <= 15 degC and
diff --git a/drivers/power/bq2419x-charger.c b/drivers/power/bq2419x-charger.c
index c9bbbeb67cd0..78e3a5719a1a 100644
--- a/drivers/power/bq2419x-charger.c
+++ b/drivers/power/bq2419x-charger.c
@@ -1065,10 +1065,11 @@ static int bq2419x_charger_thermal_configure(
 	struct bq2419x_chip *bq2419x = battery_charger_get_drvdata(bc_dev);
 	struct bq2419x_charger_platform_data *chg_pdata;
 	int fast_charge_current = 0;
+	u32 charge_voltage_limit = 0;
 	int ichg;
 	int ret;
 	int i;
-	int curr_ichg;
+	int curr_ichg, vreg;
 
 	chg_pdata = bq2419x->charger_pdata;
 	if (!bq2419x->cable_connected || !chg_pdata->n_temp_profile)
@@ -1084,6 +1085,9 @@ static int bq2419x_charger_thermal_configure(
 	for (i = 0; i < chg_pdata->n_temp_profile; ++i) {
 		if (temp <= chg_pdata->temp_range[i]) {
 			fast_charge_current = chg_pdata->chg_current_limit[i];
+			if (chg_pdata->chg_thermal_voltage_limit)
+				charge_voltage_limit =
+					chg_pdata->chg_thermal_voltage_limit[i];
 			break;
 		}
 	}
@@ -1109,6 +1113,23 @@ static int bq2419x_charger_thermal_configure(
 		dev_err(bq2419x->dev, "CHRG_CTRL_REG update failed %d\n", ret);
 		return ret;
 	}
+
+	if (!charge_voltage_limit)
+		return 0;
+
+	/* Charge voltage limit */
+	vreg = bq2419x_val_to_reg(charge_voltage_limit,
+			BQ2419X_CHARGE_VOLTAGE_OFFSET, 16, 6, 1);
+	bq2419x->chg_voltage_control.mask = BQ2419X_CHG_VOLT_LIMIT_MASK;
+	bq2419x->chg_voltage_control.val = vreg << 2;
+	ret = regmap_update_bits(bq2419x->regmap, BQ2419X_VOLT_CTRL_REG,
+				bq2419x->chg_voltage_control.mask,
+				bq2419x->chg_voltage_control.val);
+	if (ret < 0) {
+		dev_err(bq2419x->dev, "VOLT_CTRL_REG update failed %d\n", ret);
+		return ret;
+	}
+
 	return 0;
 }
 
@@ -1159,7 +1180,7 @@ static struct bq2419x_platform_data *bq2419x_dt_parse(struct i2c_client *client)
 
 	batt_reg_node = of_find_node_by_name(np, "charger");
 	if (batt_reg_node) {
-		int temp_range_len, chg_current_lim_len;
+		int temp_range_len, chg_current_lim_len, chg_voltage_lim_len;
 		int wdt_timeout;
 		int chg_restart_time;
 		int temp_polling_time;
@@ -1258,6 +1279,11 @@ static struct bq2419x_platform_data *bq2419x_dt_parse(struct i2c_client *client)
 					"ti,temp-range");
 		chg_current_lim_len = of_property_count_u32(batt_reg_node,
 					"ti,charge-current-limit");
+		if (!chg_current_lim_len)
+			chg_current_lim_len = of_property_count_u32(batt_reg_node,
+					"ti,charge-thermal-current-limit");
+		chg_voltage_lim_len = of_property_count_u32(batt_reg_node,
+					"ti,charge-thermal-voltage-limit");
 		if (temp_range_len < 0)
 			goto skip_therm_profile;
 
@@ -1267,6 +1293,12 @@ static struct bq2419x_platform_data *bq2419x_dt_parse(struct i2c_client *client)
 			goto skip_therm_profile;
 		}
 
+		if (chg_voltage_lim_len && (temp_range_len != chg_voltage_lim_len)) {
+			dev_info(&client->dev,
+				"thermal profile data is not correct\n");
+			goto skip_therm_profile;
+		}
+
 		chg_pdata->temp_range = devm_kzalloc(&client->dev,
 				sizeof(u32) * temp_range_len, GFP_KERNEL);
 		if (!chg_pdata->temp_range)
@@ -1287,8 +1319,31 @@ static struct bq2419x_platform_data *bq2419x_dt_parse(struct i2c_client *client)
 				chg_pdata->chg_current_limit,
 				temp_range_len);
 		if (ret < 0)
+			ret = of_property_read_u32_array(batt_reg_node,
+				"ti,charge-thermal-current-limit",
+					chg_pdata->chg_current_limit,
+					temp_range_len);
+		if (ret < 0)
+			return ERR_PTR(ret);
+
+		if (!chg_voltage_lim_len)
+			goto skip_thermal_volt_profle;
+
+		chg_pdata->chg_thermal_voltage_limit =
+					devm_kzalloc(&client->dev,
+					sizeof(u32) * temp_range_len,
+					GFP_KERNEL);
+		if (!chg_pdata->chg_thermal_voltage_limit)
+			return ERR_PTR(-ENOMEM);
+
+		ret = of_property_read_u32_array(batt_reg_node,
+				"ti,charge-thermal-voltage-limit",
+				chg_pdata->chg_thermal_voltage_limit,
+				temp_range_len);
+		if (ret < 0)
 			return ERR_PTR(ret);
 
+skip_thermal_volt_profle:
 		chg_pdata->n_temp_profile = temp_range_len;
 
 skip_therm_profile:
diff --git a/include/linux/power/bq2419x-charger.h b/include/linux/power/bq2419x-charger.h
index 19de230058f3..128d2a1e74c1 100644
--- a/include/linux/power/bq2419x-charger.h
+++ b/include/linux/power/bq2419x-charger.h
@@ -148,6 +148,7 @@ struct bq2419x_charger_platform_data {
 	int n_temp_profile;
 	u32 *temp_range;
 	u32 *chg_current_limit;
+	u32 *chg_thermal_voltage_limit;
 };
 
 /*