Currently the sign for CURRENT_NOW and CURRENT_AVG is a bit of a mess. There are basically 3 different ways battery fuel gauges report the current:
1. uses negative values for discharging and positive values for charging 2. uses positive values for discharging and negative values for discharging (opposit of 1) 3. only uses positive values As a result userspace currently cannot use the sign at all in a generic way. Let's solve the issue by documenting a canonical way for reporting the data and ensure new drivers follow this way. Then existing drivers can be fixed on a case-by-case basis. The 'negative value = battery discharging' has been choosen, since there are only very few drivers doing it the other way around. Signed-off-by: Sebastian Reichel <[email protected]> --- Documentation/ABI/testing/sysfs-class-power | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-class-power b/Documentation/ABI/testing/sysfs-class-power index 651599fb18f8..dbccb2fcd7ce 100644 --- a/Documentation/ABI/testing/sysfs-class-power +++ b/Documentation/ABI/testing/sysfs-class-power @@ -108,7 +108,8 @@ Description: which they average readings to smooth out the reported value. Access: Read - Valid values: Represented in microamps + Valid values: Represented in microamps. Negative values are used + for discharging batteries, positive values for charging batteries. What: /sys/class/power_supply/<supply_name>/current_max Date: October 2010 @@ -127,7 +128,8 @@ Description: This value is not averaged/smoothed. Access: Read - Valid values: Represented in microamps + Valid values: Represented in microamps. Negative values are used + for discharging batteries, positive values for charging batteries. What: /sys/class/power_supply/<supply_name>/charge_control_limit Date: Oct 2012 -- 2.28.0
