|Summary:||unable to change LCD brightness on Lenovo Thinkpad Edge E145|
|Component:||kern||Assignee:||Andriy Gapon <avg>|
|Severity:||Affects Some People||CC:||Scoobi_doo, avg|
Description aeuii 2016-02-10 17:28:05 UTC
I'm unable to change LCD brightness on Lenovo Thinkpad Edge E145 using ☼+ and ☼- buttons. To be more specific, the brightness can be changed only until an early system boot. It works in the loader menu, and right after kernel is loaded, but stops working soon after that (perhaps when acpi0 is loaded: “acpi0: <LENOVO TP-HS> on motherboard”). I tested multiple FreeBSD version: Affected FreeBSD versions: - 11.0: FreeBSD-11.0-CURRENT-amd64-20160206-r295345-memstick.img - 10.3: FreeBSD-10.3-PRERELEASE-amd64-20160127-r294913-memstick.img - 10.2: 10.2-RELEASE-p12 - 10.1: FreeBSD-10.1-RELEASE-amd64-memstick.img Working version: - 9.3: FreeBSD-9.3-RELEASE-amd64-memstick.img (with “CPU0: local ACPI error 0x80”) As you can see, the problem occurred between 9.3 and 10.1. I also tried different methods to change the brightness on 10.2: acpi_call ========= acpi_call -v -p '\VBRU' Path: \VBRU Number of arguments: 0 ioctl: Device not configured # no effect acpi_ibm ======== sysctl dev.acpi_ibm.0.lcd_brightness=7 # value changes, but it no effect on the brightness acpi_video ========== sysctl hw.acpi.video.lcd0.brightness=50 hw.acpi.video.lcd0.brightness: 50 -> # # no effect pressing Fn+☼+- buttons has no effect, but logs: can't evaluate \134_SB_.PCI0.VGA_.LCD_._BQC - AE_NOT_FOUND
Comment 1 Anthony Jenkins 2017-10-31 00:57:24 UTC
A missing _BQC method was one of my problems; I modified my DSDT to add a _BQC method, but later I patched the kernel to not complain if it was missing. The other problem was the backlight code in the kernel for Radeon chipsets. I'll stick both patches here (git-based).
Comment 2 Anthony Jenkins 2017-10-31 00:59:25 UTC
Created attachment 187601 [details] Store brightness value in static variable; don't complain if _BQC method is missing.
Comment 3 Anthony Jenkins 2017-10-31 01:02:08 UTC
Created attachment 187602 [details] Add rudimentary backlight support to Radeon chipsets.
Comment 4 Kubilay Kocak 2019-03-11 02:04:20 UTC
If this is still an issue (not resolved already in drm-kmod), should the Radeon bits (in attachment 187602 [details]) be sent to drm-kmod upstream since drm was removed from base?
Comment 5 aeuii 2019-03-11 09:03:44 UTC
(In reply to Kubilay Kocak from comment #4) I'm not able to test this any more. So I'm unable to confirm if this is still an issue or not.
Comment 6 commit-hook 2020-05-05 12:14:31 UTC
A commit references this bug: Author: avg Date: Tue May 5 12:14:12 UTC 2020 New revision: 360657 URL: https://svnweb.freebsd.org/changeset/base/360657 Log: acpi_video: try our best to work on systems without non-essential methods Only _BCL and _BCM methods seem to be essential to the driver's operation. If _BQC is missing then we can assume that the current brightness is whatever we set by the last _BCM invocation. If _DCS or _DGS is missing the we can make assumptions as well. The change is based on a patch suggested by Anthony Jenkins <Scoobi_doo@yahoo.com> in PR 207086. PR: 207086 Submitted by: Anthony Jenkins <Scoobi_doo@yahoo.com (earlier version) Reviewed by: manu MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D24653 Changes: head/sys/dev/acpica/acpi_video.c
Comment 7 Andriy Gapon 2020-05-05 13:32:48 UTC
I think that the second patch from Anthony is obsolete now because drm has been removed from the FreeBSD source tree.
Comment 8 Anthony Jenkins 2020-05-05 15:36:49 UTC
(In reply to Andriy Gapon from comment #7) I agree; I'd have to port my patch to graphics/drm-*-kmod. I've been tinkering with an ACPI backlight driver implementation similar to Linux', but I'm not happy with my port from Linux. I think their implementation got spackled with patches for all the backlight variations (as avg@ noted in code review). Thanks everyone for your work on this!
Comment 9 commit-hook 2020-05-26 05:54:04 UTC
A commit references this bug: Author: avg Date: Tue May 26 05:54:00 UTC 2020 New revision: 361495 URL: https://svnweb.freebsd.org/changeset/base/361495 Log: MFC r360657: acpi_video: support systems without non-essential methods Only _BCL and _BCM methods seem to be essential to the driver's operation. If _BQC is missing then we can assume that the current brightness is whatever we set by the last _BCM invocation. If _DCS or _DGS is missing then we can make assumptions as well. The change is based on a patch suggested by Anthony Jenkins <Scoobi_doo@yahoo.com> in PR 207086. PR: 207086 Changes: _U stable/12/ stable/12/sys/dev/acpica/acpi_video.c