power: supply: ab8500: Standardize alert mode charging

The AB8500 code is using a special current and voltage setting
when the battery is in "alert mode", i.e. when it is starting
to go outside normal operating conditions so it is too
cold or too hot. This makes sense as a way for the charging
algorithm to deal with hostile environments.

Add the needed members to the struct power_supply_battery_info,
and switch the AB8500 charging code over to using this.

Reviewed-by: Matti Vaittineen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

4 files changed, 49 insertions, 22 deletions

diff --git a/drivers/power/supply/ab8500-bm.h b/drivers/power/supply/ab8500-bm.h
index 4d74d21cf1eb..91ef9d4a5222 100644
--- a/drivers/power/supply/ab8500-bm.h
+++ b/drivers/power/supply/ab8500-bm.h
@@ -331,14 +331,10 @@ struct ab8500_maxim_parameters {
  * struct ab8500_battery_type - different batteries supported
  * @resis_high:			battery upper resistance limit
  * @resis_low:			battery lower resistance limit
- * @low_high_cur_lvl:		charger current in temp low/high state in mA
- * @low_high_vol_lvl:		charger voltage in temp low/high state in mV'
  */
 struct ab8500_battery_type {
 	int resis_high;
 	int resis_low;
-	int low_high_cur_lvl;
-	int low_high_vol_lvl;
 };
 
 /**
diff --git a/drivers/power/supply/ab8500_bmdata.c b/drivers/power/supply/ab8500_bmdata.c
index 66a454942c7c..bf0b74773eee 100644
--- a/drivers/power/supply/ab8500_bmdata.c
+++ b/drivers/power/supply/ab8500_bmdata.c
@@ -77,8 +77,6 @@ static struct power_supply_maintenance_charge_table ab8500_maint_charg_table[] =
 static struct ab8500_battery_type bat_type_thermistor_unknown = {
 	.resis_high = 0,
 	.resis_low = 0,
-	.low_high_cur_lvl = 300,
-	.low_high_vol_lvl = 4000,
 };
 
 static const struct ab8500_bm_capacity_levels cap_levels = {
@@ -192,6 +190,19 @@ int ab8500_bm_of_probe(struct power_supply *psy,
 		bi->maintenance_charge_size = ARRAY_SIZE(ab8500_maint_charg_table);
 	}
 
+	if (bi->alert_low_temp_charge_current_ua < 0 ||
+	    bi->alert_low_temp_charge_voltage_uv < 0)
+	{
+		bi->alert_low_temp_charge_current_ua = 300000;
+		bi->alert_low_temp_charge_voltage_uv = 4000000;
+	}
+	if (bi->alert_high_temp_charge_current_ua < 0 ||
+	    bi->alert_high_temp_charge_voltage_uv < 0)
+	{
+		bi->alert_high_temp_charge_current_ua = 300000;
+		bi->alert_high_temp_charge_voltage_uv = 4000000;
+	}
+
 	/*
 	 * Internal resistance and factory resistance are tightly coupled
 	 * so both MUST be defined or we fall back to defaults.
diff --git a/drivers/power/supply/ab8500_chargalg.c b/drivers/power/supply/ab8500_chargalg.c
index 6054996b6260..c9c7f7028af6 100644
--- a/drivers/power/supply/ab8500_chargalg.c
+++ b/drivers/power/supply/ab8500_chargalg.c
@@ -149,7 +149,8 @@ struct ab8500_chargalg_events {
 	bool batt_ovv;
 	bool batt_rem;
 	bool btemp_underover;
-	bool btemp_lowhigh;
+	bool btemp_low;
+	bool btemp_high;
 	bool main_thermal_prot;
 	bool usb_thermal_prot;
 	bool main_ovv;
@@ -684,26 +685,31 @@ static void ab8500_chargalg_check_temp(struct ab8500_chargalg *di)
 		di->batt_data.temp < (bi->temp_alert_max - di->t_hyst_norm)) {
 		/* Temp OK! */
 		di->events.btemp_underover = false;
-		di->events.btemp_lowhigh = false;
+		di->events.btemp_low = false;
+		di->events.btemp_high = false;
 		di->t_hyst_norm = 0;
 		di->t_hyst_lowhigh = 0;
 	} else {
-		if (((di->batt_data.temp >= bi->temp_alert_max) &&
-			(di->batt_data.temp <
-				(bi->temp_max - di->t_hyst_lowhigh))) ||
-			((di->batt_data.temp >
-				(bi->temp_min + di->t_hyst_lowhigh)) &&
-			(di->batt_data.temp <= bi->temp_alert_min))) {
-			/* TEMP minor!!!!! */
+		if ((di->batt_data.temp >= bi->temp_alert_max) &&
+		    (di->batt_data.temp < (bi->temp_max - di->t_hyst_lowhigh))) {
+			/* Alert zone for high temperature */
 			di->events.btemp_underover = false;
-			di->events.btemp_lowhigh = true;
+			di->events.btemp_high = true;
+			di->t_hyst_norm = di->bm->temp_hysteresis;
+			di->t_hyst_lowhigh = 0;
+		} else if ((di->batt_data.temp > (bi->temp_min + di->t_hyst_lowhigh)) &&
+			   (di->batt_data.temp <= bi->temp_alert_min)) {
+			/* Alert zone for low temperature */
+			di->events.btemp_underover = false;
+			di->events.btemp_low = true;
 			di->t_hyst_norm = di->bm->temp_hysteresis;
 			di->t_hyst_lowhigh = 0;
 		} else if (di->batt_data.temp <= bi->temp_min ||
 			di->batt_data.temp >= bi->temp_max) {
 			/* TEMP major!!!!! */
 			di->events.btemp_underover = true;
-			di->events.btemp_lowhigh = false;
+			di->events.btemp_low = false;
+			di->events.btemp_high = false;
 			di->t_hyst_norm = 0;
 			di->t_hyst_lowhigh = di->bm->temp_hysteresis;
 		} else {
@@ -1313,7 +1319,7 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 			ab8500_chargalg_state_to(di, STATE_WD_EXPIRED_INIT);
 	}
 	/* Battery temp high/low */
-	else if (di->events.btemp_lowhigh) {
+	else if (di->events.btemp_low || di->events.btemp_high) {
 		if (di->charge_state != STATE_TEMP_LOWHIGH)
 			ab8500_chargalg_state_to(di, STATE_TEMP_LOWHIGH_INIT);
 	}
@@ -1510,9 +1516,19 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 		break;
 
 	case STATE_TEMP_LOWHIGH_INIT:
-		ab8500_chargalg_start_charging(di,
-			di->bm->bat_type->low_high_vol_lvl,
-			di->bm->bat_type->low_high_cur_lvl);
+		if (di->events.btemp_low) {
+			ab8500_chargalg_start_charging(di,
+				       bi->alert_low_temp_charge_voltage_uv,
+				       bi->alert_low_temp_charge_current_ua);
+		} else if (di->events.btemp_high) {
+			ab8500_chargalg_start_charging(di,
+				       bi->alert_high_temp_charge_voltage_uv,
+				       bi->alert_high_temp_charge_current_ua);
+		} else {
+			dev_err(di->dev, "neither low or high temp event occured\n");
+			ab8500_chargalg_state_to(di, STATE_NORMAL_INIT);
+			break;
+		}
 		ab8500_chargalg_stop_maintenance_timer(di);
 		di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
 		ab8500_chargalg_state_to(di, STATE_TEMP_LOWHIGH);
@@ -1520,7 +1536,7 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 		fallthrough;
 
 	case STATE_TEMP_LOWHIGH:
-		if (!di->events.btemp_lowhigh)
+		if (!di->events.btemp_low && !di->events.btemp_high)
 			ab8500_chargalg_state_to(di, STATE_NORMAL_INIT);
 		break;
 
diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index accbbd36bfe7..e3d6d3ff492a 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -596,6 +596,10 @@ int power_supply_get_battery_info(struct power_supply *psy,
 	info->charge_restart_voltage_uv      = -EINVAL;
 	info->overvoltage_limit_uv           = -EINVAL;
 	info->maintenance_charge             = NULL;
+	info->alert_low_temp_charge_current_ua = -EINVAL;
+	info->alert_low_temp_charge_voltage_uv = -EINVAL;
+	info->alert_high_temp_charge_current_ua = -EINVAL;
+	info->alert_high_temp_charge_voltage_uv = -EINVAL;
 	info->temp_ambient_alert_min         = INT_MIN;
 	info->temp_ambient_alert_max         = INT_MAX;
 	info->temp_alert_min                 = INT_MIN;