On 3/8/21, Subhaditya Nath <sn03.gene...@gmail.com> wrote:
> I have a Thinkpad E495 that has Battery Charge threshold support. i.e.
> it can be set such that the battery starts charging at a specified
> amount of charge (say, 70%) and automatically stops charging at a
> specified charge (say, 80%). This feature is also available on Linux by
> using TLP (made by linrunner, his website is linrunner.de)

I just investigated a little more about it, and what do I see? Surprise!
It's just a shell script! Yeah! And how does it do the threshold thing?
Simple! It just writes the required values to -
        /sys/class/power_supply/BAT0/charge_start_threshold
        /sys/class/power_supply/BAT0/charge_stop_threshold
Done!


And the actual work is done by something called the 'natacpi framework',
which is implemented by the linux kernel itself. I don't know :shrug:
(I just gathered the above sentence after a few minutes of googling. I
know very little about the kernel and all)


For those who are curious, below is the output of `tlp-stat -b`.

Note this line -
        natacpi    = active (data, thresholds)


--- TLP 1.3.1 --------------------------------------------

+++ Battery Features: Charge Thresholds and Recalibrate
natacpi    = active (data, thresholds)
tpacpi-bat = active (recalibrate)
tp-smapi   = inactive (ThinkPad not supported)

+++ ThinkPad Battery Status: BAT0 (Main / Internal)
/sys/class/power_supply/BAT0/manufacturer                   = SMP
/sys/class/power_supply/BAT0/model_name                     = 01AV446
/sys/class/power_supply/BAT0/cycle_count                    =    205
/sys/class/power_supply/BAT0/energy_full_design             =  45280 [mWh]
/sys/class/power_supply/BAT0/energy_full                    =  42750 [mWh]
/sys/class/power_supply/BAT0/energy_now                     =  26430 [mWh]
/sys/class/power_supply/BAT0/power_now                      =   6810 [mW]
/sys/class/power_supply/BAT0/status                         = Discharging

/sys/class/power_supply/BAT0/charge_start_threshold         =     75 [%]
/sys/class/power_supply/BAT0/charge_stop_threshold          =     80 [%]
tpacpi-bat.BAT0.forceDischarge                              =      0

Charge                                                      =   61.8 [%]
Capacity                                                    =   94.4 [%]

Reply via email to