power_supply: Add voltage_ocv property and use it for max17042 driver

This adds a new sysfs file called 'voltage_ocv' which gives the
Open Circuit Voltage of the battery.

This property can be used for platform shutdown policies and
can be useful for initial capacity estimations.

Note: This patch is generated against linux-next branch.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

diff --git a/Documentation/power/power_supply_class.txt b/Documentation/power/power_supply_class.txt
index 9f16c5178b662b8f9ec67f3dd7eafd6f4c89e39a..211831d4095fef63eacb13a2dbde8d647b5499a6 100644 (file)
--- a/Documentation/power/power_supply_class.txt
+++ b/Documentation/power/power_supply_class.txt
@@ -84,6 +84,8 @@ are already charged or discharging, 'n/a' can be displayed (or
 HEALTH - represents health of the battery, values corresponds to
 POWER_SUPPLY_HEALTH_*, defined in battery.h.
 
+VOLTAGE_OCV - open circuit voltage of the battery.
+
 VOLTAGE_MAX_DESIGN, VOLTAGE_MIN_DESIGN - design values for maximal and
 minimal power supply voltages. Maximal/minimal means values of voltages
 when battery considered "full"/"empty" at normal conditions. Yes, there is

diff --git a/drivers/power/max17042_battery.c b/drivers/power/max17042_battery.c
index 738648d1d9fcba4d5a728d9642966c0727618785..42c4be9a664ba6ddd2d871bcad31aab3151a1935 100644 (file)
--- a/drivers/power/max17042_battery.c
+++ b/drivers/power/max17042_battery.c
@@ -106,6 +106,7 @@ static enum power_supply_property max17042_battery_props[] = {
        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
        POWER_SUPPLY_PROP_VOLTAGE_AVG,
+       POWER_SUPPLY_PROP_VOLTAGE_OCV,
        POWER_SUPPLY_PROP_CAPACITY,
        POWER_SUPPLY_PROP_CHARGE_FULL,
        POWER_SUPPLY_PROP_TEMP,
@@ -170,6 +171,13 @@ static int max17042_get_property(struct power_supply *psy,
                if (ret < 0)
                        return ret;
 
+               val->intval = ret * 625 / 8;
+               break;
+       case POWER_SUPPLY_PROP_VOLTAGE_OCV:
+               ret = max17042_read_reg(chip->client, MAX17042_OCVInternal);
+               if (ret < 0)
+                       return ret;
+
                val->intval = ret * 625 / 8;
                break;
        case POWER_SUPPLY_PROP_CAPACITY:

diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
index 4368e7d61316bb37c9a3565ca1c0400964aa6781..4150747f9186f8dfaff9faf81bf03a7ade8cb9fa 100644 (file)
--- a/drivers/power/power_supply_sysfs.c
+++ b/drivers/power/power_supply_sysfs.c
@@ -146,6 +146,7 @@ static struct device_attribute power_supply_attrs[] = {
        POWER_SUPPLY_ATTR(voltage_min_design),
        POWER_SUPPLY_ATTR(voltage_now),
        POWER_SUPPLY_ATTR(voltage_avg),
+       POWER_SUPPLY_ATTR(voltage_ocv),
        POWER_SUPPLY_ATTR(current_max),
        POWER_SUPPLY_ATTR(current_now),
        POWER_SUPPLY_ATTR(current_avg),

diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index c38c13db8832e7b3c15440807e7e7719a5603792..fd17ae0f9c20b3f06ed501bfd42f5af67f558588 100644 (file)
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -96,6 +96,7 @@ enum power_supply_property {
        POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
        POWER_SUPPLY_PROP_VOLTAGE_NOW,
        POWER_SUPPLY_PROP_VOLTAGE_AVG,
+       POWER_SUPPLY_PROP_VOLTAGE_OCV,
        POWER_SUPPLY_PROP_CURRENT_MAX,
        POWER_SUPPLY_PROP_CURRENT_NOW,
        POWER_SUPPLY_PROP_CURRENT_AVG,
@@ -261,6 +262,7 @@ static inline bool power_supply_is_watt_property(enum power_supply_property psp)
        case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
        case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+       case POWER_SUPPLY_PROP_VOLTAGE_OCV:
        case POWER_SUPPLY_PROP_POWER_NOW:
                return 1;
        default: