ACPI: battery: Convert discharge energy rate to current properly

ACPI battery interface reports its state either in mW or in mA, and
discharge rate in your case is reported in mW. power_supply interface
does not have such a parameter, so current_now parameter is used
for all cases. But in case of mW, reported discharge should
be converted into mA.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Tested-by: Ferenc Wagner <wferi@niif.hu>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 1423b0c0cd2e..a0a178dd189c 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -174,6 +174,15 @@ static int acpi_battery_get_property(struct power_supply *psy,
                 break;
         case POWER_SUPPLY_PROP_CURRENT_NOW:
                 val->intval = battery->current_now * 1000;
+                /* if power units are mW, convert to mA by
+                   dividing by current voltage (mV/1000) */
+                if (!battery->power_unit) {
+                        if (battery->voltage_now) {
+                                val->intval /= battery->voltage_now;
+                                val->intval *= 1000;
+                        } else
+                                val->intval = -1;
+                }
                 break;
         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN: