/sys/class/power_supply/* is too broad a search, suggest scanning just /sys/class/power_supply/BAT*

[BillyCroan]

If your laptop has a peripheral device with a battery, laptop-mode-tools reacts as if that devices battery is the laptop's and reacts poorly when that peripheral doesn't support a design_capacity. I was getting tonnes of this in my syslog:

2024-01-14T20:49:11.499724-06:00 x360 laptop_mode[1483528]: WARNING: Battery does not report a capacity. Minimum battery
2024-01-14T20:49:11.502666-06:00 x360 laptop_mode[1483528]: charge checking does not work without a design capacity.
2024-01-14T20:49:11.502742-06:00 x360 laptop_mode[1483528]: WARNING: Battery does not report a design capacity. Auto hibernation
2024-01-14T20:49:11.502781-06:00 x360 laptop_mode[1483528]: does not work without a design capacity.
2024-01-14T20:49:11.502812-06:00 x360 laptop_mode[1483528]: You seem to have a broken battery
2024-01-14T20:49:11.502838-06:00 x360 laptop_mode[1483528]: Cannot determine design_capacity_warning
2024-01-14T20:49:11.502876-06:00 x360 laptop_mode[1483528]: Disabling hibernation
2024-01-14T20:49:11.502942-06:00 x360 laptop_mode[1483528]: Failed to determine battery charge. Battery charge units are not in
2024-01-14T20:49:11.502976-06:00 x360 laptop_mode[1483528]: mWh, uWh, mAh or uAh.
2024-01-14T20:49:11.503002-06:00 x360 laptop_mode[1483528]: Laptop mode
2024-01-14T20:49:11.503221-06:00 x360 laptop_mode[1483528]: enabled, active [unchanged]
2024-01-14T20:49:11.503282-06:00 x360 systemd[1]: Reloaded laptop-mode.service - Laptop Mode Tools.

This is because line750:
for BATT in /sys/class/power_supply/* ; do

That captures all batteries, when I think we're really looking for BAT0. and maybe some laptops have a BAT1 or 2

What you don't want is to match on hid-0018:04F3:272D.0002-battery or the like

So I edited like 750 to:
for BATT in /sys/class/power_supply/BAT* ; do

And now my syslog is much happier. no more angry messages.

If you really don't want to narrow * down to BAT* then perhaps check on like 751 that BATT does not begin with "hid-"

I hope this bug report helps other users who were having the broken battery warnings, and helps improve the laptop-mode-tools project.