Wrong conversion for mAh to mWh

[Richard Hughes]

in hald/linux/acpi.c:

...
if (reporting_unit && strcmp (reporting_unit, "mAh") == 0) {
        voltage_design = hal_device_property_get_int (d,
"battery.voltage.design");

        /* If design voltage is unknown, use 1mV. */
        if (voltage_design <= 0)
                voltage_design = 1;

        /* scale by factor battery.voltage.design */
        hal_device_property_set_int (d, "battery.charge_level.design",
                reporting_design * voltage_design);
        hal_device_property_set_int (d, "battery.charge_level.warning",
                reporting_warning * voltage_design);
        hal_device_property_set_int (d, "battery.charge_level.low",
                reporting_low * voltage_design);
        hal_device_property_set_int (d, "battery.charge_level.granularity_1",
                reporting_gran1 * voltage_design);
        hal_device_property_set_int (d, "battery.charge_level.granularity_2",
                reporting_gran2 * voltage_design);

        /* set unit */
        hal_device_property_set_string (d, "battery.charge_level.unit",
                "mWh"); /* not mAh! */
        }

this is wrong IMO.

You have battery.voltage.design in mV (11100)
You have battery.reporting.rate in mAh (2187)

We are currently multiplying to give:

mWh = mAh * mV

when we should be doing:

mWh = mAh * ( mV / 1000)

Is this sane or have I been revising too hard?

There's some more details here, showing a laptop consuming nearly 30kW of power!

http://bugzilla.gnome.org/show_bug.cgi?id=340403

Richard.