Bug 213109

Summary: ideapad-laptop: Regression in 5.12.x for Battery conservation mode
Product: Drivers Reporter: Fouad (fouad.fakih)
Component: Platform_x86Assignee: drivers_platform_x86 (drivers_platform_x86)
Status: RESOLVED CODE_FIX    
Severity: normal CC: jwrdegoede, pobrn
Priority: P1    
Hardware: x86-64   
OS: Linux   
Kernel Version: 5.12.4 Tree: Mainline
Regression: Yes

Description Fouad 2021-05-17 16:05:01 UTC
Enabling battery conservation mode no longer works on Linux 5.12.x for Lenovo Legion 5 15ARH05.

It works with kernel versions 5.11 and 5.10 on Arch Linux.

Modifying `/sys/bus/platform/drivers/ideapad_acpi/VPC2004:00/conservation_mode` fails with message : `Input/output error`
Comment 1 Barnabás Pőcze 2021-05-17 16:21:59 UTC
Thanks for bringing this up. The issue has already been reported in https://bugzilla.kernel.org/show_bug.cgi?id=212985 and a patch has been sent to fix it ( https://lore.kernel.org/platform-driver-x86/20210507235333.286505-1-pobrn@protonmail.com/ ).
Comment 2 Hans de Goede 2021-05-19 13:46:35 UTC
I've added the patch fixing this to the fixes branch of the pdx86 kernel tree:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=fixes

The contents of this branch will be in the next pdx86-fixes pull-req which I send to Linus for 5.13. Since the patch has a fixes tag it will get added automatically to the 5.12 kernels once Linus has merged it, so this bug can be closed now.