[PATCH] lib: fwts_battery: fix incorrect strings for a battery with unit of mWh

[Alex Hung]

On 05/25/2012 02:54 PM, IvanHu wrote:
> On 05/24/2012 10:34 AM, Alex Hung wrote:
>> Hi Colin,
>>
>> It was actually one bug that led to another topics
>>
>> == Topic 1 ==
>>
>> The one that is related to fwts is simple: when I was testing the the
>> trip point patch, I found fwts_battery_get_capacity_sys_fs always
>> returns 0 for remaining capacity. After some digging in, it is because
>> the strings mismatch as the patch.
>>
>> The below is the output from my thinkpad x200
>> ========================================================
>> @x200:~$ cat /sys/class/power_supply/BAT0/uevent
>> POWER_SUPPLY_NAME=BAT0
>> POWER_SUPPLY_STATUS=Full
>> POWER_SUPPLY_PRESENT=1
>> POWER_SUPPLY_TECHNOLOGY=Li-ion
>> POWER_SUPPLY_CYCLE_COUNT=0
>> POWER_SUPPLY_VOLTAGE_MIN_DESIGN=14400000
>> POWER_SUPPLY_VOLTAGE_NOW=16684000
>> POWER_SUPPLY_POWER_NOW=0
>> POWER_SUPPLY_ENERGY_FULL_DESIGN=28800000
>> POWER_SUPPLY_ENERGY_FULL=24430000
>> POWER_SUPPLY_ENERGY_NOW=24430000
>> POWER_SUPPLY_MODEL_NAME=42T4646
>> POWER_SUPPLY_MANUFACTURER=SANYO
>> POWER_SUPPLY_SERIAL_NUMBER= 1720
>> ========================================================
>>
>> == Topic 2 ==
>>
>> The led to the discussion we had - I was testing on x220 which has
>> such problem, and then it turns on thinkpad sometimes returns power
>> unit as mAh and sometimes as mWh, and this seems to be a BIOS bug - I
>> will send Lenovo for their feedbacks.
>>
>> Cheers,
>> Alex Hung
>>
>> On 05/24/2012 01:19 AM, Colin Ian King wrote:
>>> Although we did discuss this on irc today, I'm still struggling to
>>> understand why this is required, can explain it a little more for me.
>>> Thanks Alex.
>>>
>>> Colin
>>>
>>>
>>> On 23/05/12 14:44, Alex Hung wrote:
>>>> Signed-off-by: Alex Hung <alex.hung at canonical.com>
>>>> ---
>>>> src/lib/src/fwts_battery.c | 4 ++--
>>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/src/lib/src/fwts_battery.c b/src/lib/src/fwts_battery.c
>>>> index 5f21dfa..468c616 100644
>>>> --- a/src/lib/src/fwts_battery.c
>>>> +++ b/src/lib/src/fwts_battery.c
>>>> @@ -45,11 +45,11 @@ static int
>>>> fwts_battery_get_capacity_sys_fs(fwts_framework *fw,
>>>> switch (type) {
>>>> case FWTS_BATTERY_DESIGN_CAPACITY:
>>>> field_mAh = "POWER_SUPPLY_CHARGE_FULL_DESIGN=";
>>>> - field_mWh = "ENERGY_SUPPLY_CHARGE_FULL_DESIGN=";
>>>> + field_mWh = "POWER_SUPPLY_ENERGY_FULL_DESIGN=";
>>>> break;
>>>> case FWTS_BATTERY_REMAINING_CAPACITY:
>>>> field_mAh = "POWER_SUPPLY_CHARGE_NOW=";
>>>> - field_mWh = "ENERGY_SUPPLY_CHARGE_NOW=";
>>>> + field_mWh = "POWER_SUPPLY_ENERGY_NOW=";
>>>> break;
>>>> default:
>>>> return FWTS_ERROR;
>>>>
>>>
>>>
>>
>>
>
> Hi Alex,
>
> I've checked the uevent on my lenovo x220,
>
> ======================================
> POWER_SUPPLY_NAME=BAT0
> POWER_SUPPLY_STATUS=Unknown
> POWER_SUPPLY_PRESENT=1
> POWER_SUPPLY_TECHNOLOGY=Li-ion
> POWER_SUPPLY_CYCLE_COUNT=0
> POWER_SUPPLY_VOLTAGE_MIN_DESIGN=14800000
> POWER_SUPPLY_VOLTAGE_NOW=16422000
> POWER_SUPPLY_CURRENT_NOW=0
> POWER_SUPPLY_CHARGE_FULL_DESIGN=2886000
> POWER_SUPPLY_CHARGE_FULL=2883000
> POWER_SUPPLY_CHARGE_NOW=2787000
> POWER_SUPPLY_MODEL_NAME=42T4901
> POWER_SUPPLY_MANUFACTURER=Panasonic
> POWER_SUPPLY_SERIAL_NUMBER= 1794
> ======================================
>
> it seems using "POWER_SUPPLY_CHARGE_FULL".
>
> best regards,
> Ivan
>

Yes, it is a BIOS bug(?) that it returns mAh in _BIF (therefore 
POWER_SUPPLY_CHARGE_FULL) but it sometimes will change to mWh (and 
therefore POWER_SUPPLY_ENERGY_FULL. I was not able to duplicate it but 
it should be related to s3.