This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 1812099 and then change the status of the bug to 'Confirmed'. If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'. This change has been made by an automated script, maintained by the Ubuntu Kernel Team. ** Changed in: linux (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1812099 Title: 4.18.0 thinkpad_acpi : thresholds for BAT1 not writable Status in linux package in Ubuntu: Incomplete 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/power_supply/BAT1/charge_start_threshold bash: echo: write error: No such device echo 42 > /sys/class/power_supply/BAT0/charge_start_threshold -- primary battery works! [Fix] Problem was fixed in 4.19: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/platform/x86/thinkpad_acpi.c?h=v4.19.15&id=d22296d9c38fd29a96bb5079fb8d17cee278f40e 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_start/stop_threshold work for BAT0 and BAT. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1812099/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp