power_supply: Add new power supply properties CHARGE_CURRENT/VOLTAGE_MAX

There are different types of chargers avalibale like AC, Solar, USB,
etc..  Even in USB we have different types SDP/DCP/CDP/ACA and all these
chargers have different o/p ratings. For example SDP supports only 500mA
of charge current whereas AC charger can support upto 8A or more.

Similarly batteries also come with charge current and voltage ratings
and these ratings vary depending on its capacity and the technology
used.

This patch adds two new power supply properties
CONSTANT_CHARGE_CURRENT_MAX and CONSTANT_CHARGE_CURRENT_MAX.

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

Documentation/power/power_supply_class.txt

@@ -116,8 +116,12 @@ be negative; there is no empty or full value.  It is only useful for
 relative, time-based measurements.
 
 CONSTANT_CHARGE_CURRENT - constant charge current programmed by charger.
+CONSTANT_CHARGE_CURRENT_MAX - maximum charge current supported by the
+power supply object.
 
 CONSTANT_CHARGE_VOLTAGE - constant charge voltage programmed by charger.
+CONSTANT_CHARGE_VOLTAGE_MAX - maximum charge voltage supported by the
+power supply object.
 
 ENERGY_FULL, ENERGY_EMPTY - same as above but for energy.
 

drivers/power/power_supply_sysfs.c

@@ -161,7 +161,9 @@ static struct device_attribute power_supply_attrs[] = {
 	POWER_SUPPLY_ATTR(charge_avg),
 	POWER_SUPPLY_ATTR(charge_counter),
 	POWER_SUPPLY_ATTR(constant_charge_current),
+	POWER_SUPPLY_ATTR(constant_charge_current_max),
 	POWER_SUPPLY_ATTR(constant_charge_voltage),
+	POWER_SUPPLY_ATTR(constant_charge_voltage_max),
 	POWER_SUPPLY_ATTR(energy_full_design),
 	POWER_SUPPLY_ATTR(energy_empty_design),
 	POWER_SUPPLY_ATTR(energy_full),

include/linux/power_supply.h

@@ -111,7 +111,9 @@ enum power_supply_property {
 	POWER_SUPPLY_PROP_CHARGE_AVG,
 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
+	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
+	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 	POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN,
 	POWER_SUPPLY_PROP_ENERGY_FULL,
@@ -249,6 +251,7 @@ static inline bool power_supply_is_amp_property(enum power_supply_property psp)
 	case POWER_SUPPLY_PROP_CHARGE_AVG:
 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
+	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
 	case POWER_SUPPLY_PROP_CURRENT_MAX:
 	case POWER_SUPPLY_PROP_CURRENT_NOW:
 	case POWER_SUPPLY_PROP_CURRENT_AVG:
@@ -277,6 +280,7 @@ static inline bool power_supply_is_watt_property(enum power_supply_property psp)
 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
 	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
+	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
 	case POWER_SUPPLY_PROP_POWER_NOW:
 		return 1;
 	default: