@@ -243,10 +243,23 @@ static int acpi_battery_get_property(struct power_supply *psy,
break;
case POWER_SUPPLY_PROP_CURRENT_NOW:
case POWER_SUPPLY_PROP_POWER_NOW:
- if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
+ if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN) {
ret = -ENODEV;
- else
- val->intval = battery->rate_now * 1000;
+ break;
+ }
+
+ val->intval = battery->rate_now * 1000;
+ /*
+ * When discharging, the current should be reported as a
+ * negative number as per the power supply class interface
+ * definition.
+ */
+ if (psp == POWER_SUPPLY_PROP_CURRENT_NOW &&
+ (battery->state & ACPI_BATTERY_STATE_DISCHARGING) &&
+ acpi_battery_handle_discharging(battery)
+ == POWER_SUPPLY_STATUS_DISCHARGING)
+ val->intval = -val->intval;
+
break;
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
The ACPI specification requires that battery rate is always positive, but the kernel ABI for POWER_SUPPLY_PROP_CURRENT_NOW (Documentation/ABI/testing/sysfs-class-power) specifies that it should be negative when a battery is discharging. When reporting CURRENT_NOW, massage the value to match the documented ABI. This only changes the sign of `current_now` and not `power_now` because documentation doesn't describe any particular meaning for `power_now` so leaving `power_now` unchanged is less likely to confuse userspace unnecessarily, whereas becoming consistent with the documented ABI is worth potentially confusing clients that read `current_now`. Signed-off-by: Peter Marheine <pmarheine@chromium.org> --- drivers/acpi/battery.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-)