Bug 510294

Summary:	backlight is set to minimum
Product:	Gentoo Linux	Reporter:	Anton Gubarkov <anton.gubarkov>
Component:	[OLD] Unspecified	Assignee:	Gentoo Linux bug wranglers <bug-wranglers>
Status:	RESOLVED INVALID
Severity:	normal
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Anton Gubarkov 2014-05-14 08:55:36 UTC

some process/driver keeps switching backlight to minimal value in my new Lenovo Thinkpad T540p.

I was able to link it to the following sequence in the log:

May 14 12:53:51 r9-008cln kernel: thinkpad_acpi: EC reports that Thermal Table has changed
May 14 12:53:51 r9-008cln logger[3251]: ACPI event unhandled: ibm/hotkey LEN0068:00 00000080 00006030
May 14 12:53:51 r9-008cln logger[3253]: ACPI event unhandled: thermal_zone LNXTHERM:00 00000081 00000000
May 14 12:53:51 r9-008cln logger[3255]: ACPI event unhandled: battery PNP0C0A:00 00000080 00000001
May 14 12:53:52 r9-008cln logger[3261]: ACPI event unhandled: ac_adapter ACPI0003:00 00000080 00000001
May 14 12:53:52 r9-008cln kernel: thinkpad_ec: thinkpad_ec_request_row: arg0 rejected: (0x01:0x00)->0x00
May 14 12:53:52 r9-008cln kernel: thinkpad_ec: thinkpad_ec_read_row: failed requesting row: (0x01:0x00)->0xfffffffb
May 14 12:53:52 r9-008cln kernel: thinkpad_ec: initial ec test failed
May 14 12:53:52 r9-008cln kernel: thinkpad_acpi: EC reports that Thermal Table has changed
May 14 12:53:52 r9-008cln logger[3336]: ACPI event unhandled: ibm/hotkey LEN0068:00 00000080 00006030
May 14 12:53:52 r9-008cln logger[3338]: ACPI event unhandled: thermal_zone LNXTHERM:00 00000081 00000000
May 14 12:53:52 r9-008cln logger[3340]: ACPI event unhandled: battery PNP0C0A:00 00000080 00000001

It happens every time. correlation is 1:1
However I can't track it further, I need assistance in the direction I should poke....

Comment 1 Anton Gubarkov 2014-05-14 08:56:55 UTC

I should mention, that it happens quite often and it is annoying - from several times per minute to 1 time in 5 minutes.

Comment 2 Anton Gubarkov 2014-05-14 09:57:56 UTC

This happens when the notebook runs on AC and the main battery is fully charged

Comment 3 Alex Legler (RETIRED) archtester

2014-05-14 11:58:39 UTC

Please consult our support venues (Forums, IRC, Mailing Lists) to get help for your issue. Once you have actually identified a bug in a software component, you can post it here.