power: max17042_battery: add HEALTH and TEMP_* properties support

This patch adds the support for following battery properties
to max17042 fuel gauge driver.

POWER_SUPPLY_PROP_TEMP_ALERT_MIN
POWER_SUPPLY_PROP_TEMP_ALERT_MAX
POWER_SUPPLY_PROP_TEMP_MIN
POWER_SUPPLY_PROP_TEMP_MAX
POWER_SUPPLY_PROP_HEALTH

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

diff --git a/drivers/power/max17042_battery.c b/drivers/power/max17042_battery.c
index 6cc5e87ec031073ebda3dfea04e4899096622ba1..748d9762e89b11f20fa0390d7b38663f0bd76c94 100644 (file)
--- a/drivers/power/max17042_battery.c
+++ b/drivers/power/max17042_battery.c
@@ -63,6 +63,8 @@
 #define dP_ACC_100     0x1900
 #define dP_ACC_200     0x3200
 
+#define MAX17042_VMAX_TOLERANCE                50 /* 50 mV */
+
 struct max17042_chip {
        struct i2c_client *client;
        struct regmap *regmap;
@@ -85,10 +87,94 @@ static enum power_supply_property max17042_battery_props[] = {
        POWER_SUPPLY_PROP_CHARGE_FULL,
        POWER_SUPPLY_PROP_CHARGE_COUNTER,
        POWER_SUPPLY_PROP_TEMP,
+       POWER_SUPPLY_PROP_TEMP_ALERT_MIN,
+       POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
+       POWER_SUPPLY_PROP_TEMP_MIN,
+       POWER_SUPPLY_PROP_TEMP_MAX,
+       POWER_SUPPLY_PROP_HEALTH,
        POWER_SUPPLY_PROP_CURRENT_NOW,
        POWER_SUPPLY_PROP_CURRENT_AVG,
 };
 
+static int max17042_get_temperature(struct max17042_chip *chip, int *temp)
+{
+       int ret;
+       u32 data;
+       struct regmap *map = chip->regmap;
+
+       ret = regmap_read(map, MAX17042_TEMP, &data);
+       if (ret < 0)
+               return ret;
+
+       *temp = data;
+       /* The value is signed. */
+       if (*temp & 0x8000) {
+               *temp = (0x7fff & ~*temp) + 1;
+               *temp *= -1;
+       }
+
+       /* The value is converted into deci-centigrade scale */
+       /* Units of LSB = 1 / 256 degree Celsius */
+       *temp = *temp * 10 / 256;
+       return 0;
+}
+
+static int max17042_get_battery_health(struct max17042_chip *chip, int *health)
+{
+       int temp, vavg, vbatt, ret;
+       u32 val;
+
+       ret = regmap_read(chip->regmap, MAX17042_AvgVCELL, &val);
+       if (ret < 0)
+               goto health_error;
+
+       /* bits [0-3] unused */
+       vavg = val * 625 / 8;
+       /* Convert to millivolts */
+       vavg /= 1000;
+
+       ret = regmap_read(chip->regmap, MAX17042_VCELL, &val);
+       if (ret < 0)
+               goto health_error;
+
+       /* bits [0-3] unused */
+       vbatt = val * 625 / 8;
+       /* Convert to millivolts */
+       vbatt /= 1000;
+
+       if (vavg < chip->pdata->vmin) {
+               *health = POWER_SUPPLY_HEALTH_DEAD;
+               goto out;
+       }
+
+       if (vbatt > chip->pdata->vmax + MAX17042_VMAX_TOLERANCE) {
+               *health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+               goto out;
+       }
+
+       ret = max17042_get_temperature(chip, &temp);
+       if (ret < 0)
+               goto health_error;
+
+       if (temp <= chip->pdata->temp_min) {
+               *health = POWER_SUPPLY_HEALTH_COLD;
+               goto out;
+       }
+
+       if (temp >= chip->pdata->temp_max) {
+               *health = POWER_SUPPLY_HEALTH_OVERHEAT;
+               goto out;
+       }
+
+       *health = POWER_SUPPLY_HEALTH_GOOD;
+
+out:
+       return 0;
+
+health_error:
+       return ret;
+}
+
 static int max17042_get_property(struct power_supply *psy,
                            enum power_supply_property psp,
                            union power_supply_propval *val)
@@ -181,19 +267,34 @@ static int max17042_get_property(struct power_supply *psy,
                val->intval = data * 1000 / 2;
                break;
        case POWER_SUPPLY_PROP_TEMP:
-               ret = regmap_read(map, MAX17042_TEMP, &data);
+               ret = max17042_get_temperature(chip, &val->intval);
+               if (ret < 0)
+                       return ret;
+               break;
+       case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
+               ret = regmap_read(map, MAX17042_TALRT_Th, &data);
+               if (ret < 0)
+                       return ret;
+               /* LSB is Alert Minimum. In deci-centigrade */
+               val->intval = (data & 0xff) * 10;
+               break;
+       case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
+               ret = regmap_read(map, MAX17042_TALRT_Th, &data);
+               if (ret < 0)
+                       return ret;
+               /* MSB is Alert Maximum. In deci-centigrade */
+               val->intval = (data >> 8) * 10;
+               break;
+       case POWER_SUPPLY_PROP_TEMP_MIN:
+               val->intval = chip->pdata->temp_min;
+               break;
+       case POWER_SUPPLY_PROP_TEMP_MAX:
+               val->intval = chip->pdata->temp_max;
+               break;
+       case POWER_SUPPLY_PROP_HEALTH:
+               ret = max17042_get_battery_health(chip, &val->intval);
                if (ret < 0)
                        return ret;
-
-               val->intval = data;
-               /* The value is signed. */
-               if (val->intval & 0x8000) {
-                       val->intval = (0x7fff & ~val->intval) + 1;
-                       val->intval *= -1;
-               }
-               /* The value is converted into deci-centigrade scale */
-               /* Units of LSB = 1 / 256 degree Celsius */
-               val->intval = val->intval * 10 / 256;
                break;
        case POWER_SUPPLY_PROP_CURRENT_NOW:
                if (chip->pdata->enable_current_sense) {
@@ -237,6 +338,69 @@ static int max17042_get_property(struct power_supply *psy,
        return 0;
 }
 
+static int max17042_set_property(struct power_supply *psy,
+                           enum power_supply_property psp,
+                           const union power_supply_propval *val)
+{
+       struct max17042_chip *chip = power_supply_get_drvdata(psy);
+       struct regmap *map = chip->regmap;
+       int ret = 0;
+       u32 data;
+       int8_t temp;
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
+               ret = regmap_read(map, MAX17042_TALRT_Th, &data);
+               if (ret < 0)
+                       return ret;
+
+               /* Input in deci-centigrade, convert to centigrade */
+               temp = val->intval / 10;
+               /* force min < max */
+               if (temp >= (int8_t)(data >> 8))
+                       temp = (int8_t)(data >> 8) - 1;
+               /* Write both MAX and MIN ALERT */
+               data = (data & 0xff00) + temp;
+               ret = regmap_write(map, MAX17042_TALRT_Th, data);
+               break;
+       case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
+               ret = regmap_read(map, MAX17042_TALRT_Th, &data);
+               if (ret < 0)
+                       return ret;
+
+               /* Input in Deci-Centigrade, convert to centigrade */
+               temp = val->intval / 10;
+               /* force max > min */
+               if (temp <= (int8_t)(data & 0xff))
+                       temp = (int8_t)(data & 0xff) + 1;
+               /* Write both MAX and MIN ALERT */
+               data = (data & 0xff) + (temp << 8);
+               ret = regmap_write(map, MAX17042_TALRT_Th, data);
+               break;
+       default:
+               ret = -EINVAL;
+       }
+
+       return ret;
+}
+
+static int max17042_property_is_writeable(struct power_supply *psy,
+               enum power_supply_property psp)
+{
+       int ret;
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_TEMP_ALERT_MIN:
+       case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
+               ret = 1;
+               break;
+       default:
+               ret = 0;
+       }
+
+       return ret;
+}
+
 static int max17042_write_verify_reg(struct regmap *map, u8 reg, u32 value)
 {
        int retries = 8;
@@ -665,6 +829,8 @@ static const struct power_supply_desc max17042_psy_desc = {
        .name           = "max170xx_battery",
        .type           = POWER_SUPPLY_TYPE_BATTERY,
        .get_property   = max17042_get_property,
+       .set_property   = max17042_set_property,
+       .property_is_writeable  = max17042_property_is_writeable,
        .properties     = max17042_battery_props,
        .num_properties = ARRAY_SIZE(max17042_battery_props),
 };
@@ -673,6 +839,8 @@ static const struct power_supply_desc max17042_no_current_sense_psy_desc = {
        .name           = "max170xx_battery",
        .type           = POWER_SUPPLY_TYPE_BATTERY,
        .get_property   = max17042_get_property,
+       .set_property   = max17042_set_property,
+       .property_is_writeable  = max17042_property_is_writeable,
        .properties     = max17042_battery_props,
        .num_properties = ARRAY_SIZE(max17042_battery_props) - 2,
 };

diff --git a/include/linux/power/max17042_battery.h b/include/linux/power/max17042_battery.h
index cf112b4075c872f81ae87c972d4d823b10d36526..522757ac9cd4d9975a5fe8bbbf144efb54551cd4 100644 (file)
--- a/include/linux/power/max17042_battery.h
+++ b/include/linux/power/max17042_battery.h
@@ -215,6 +215,10 @@ struct max17042_platform_data {
         * the datasheet although it can be changed by board designers.
         */
        unsigned int r_sns;
+       int         vmin;       /* in millivolts */
+       int         vmax;       /* in millivolts */
+       int         temp_min;   /* in tenths of degree Celsius */
+       int         temp_max;   /* in tenths of degree Celsius */
 };
 
 #endif /* __MAX17042_BATTERY_H_ */