4.18.0 thinkpad_acpi : thresholds for BAT1 not writable
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Undecided
|
Unassigned | ||
Cosmic |
Fix Released
|
Medium
|
Unassigned |
Bug Description
[Problem description]
Kernel 4.17 introduced a new interface to set charge thresholds: The interface remained unchanged with 4.18. There's a bug preventing writing the charge thresholds for the secondary battery (BAT1).
[Impact]
ThinkPads with two batteries (ThinkPad "power bridge") e.g.
X240, T440(s), X250, T450(s), X260, T460(s), X270, T470(s) et al.
[Steps to reproduce]
echo 42 > /sys/class/
bash: echo: write error: No such device
echo 42 > /sys/class/
-- primary battery works!
[Fix]
Problem was fixed in 4.19:
https:/
I propose to cherry-pick the patch for 4.18.
[Test Case]
See above, a patched 4.18 works for T450s.
[Regression Potential]
Low. This patch only applies to several ThinkPad machines, and after applying
this patch, charge_
tags: | added: patch |
Changed in linux (Ubuntu): | |
status: | Confirmed → Fix Released |
Changed in linux (Ubuntu Cosmic): | |
importance: | Undecided → Medium |
Changed in linux (Ubuntu Cosmic): | |
status: | New → Fix Committed |
Is commit 6640ee6289b9974 334e36d8283fc07 f37f3b235d also needed?