Bug 72321
Summary: | 8086:0412 [HP ENVY TouchSmart 23se-d494 All-in-One Desktop PC] No backlight interface | ||
---|---|---|---|
Product: | Drivers | Reporter: | lee.joshwa |
Component: | Video(DRI - Intel) | Assignee: | intel-gfx-bugs (intel-gfx-bugs) |
Status: | RESOLVED INVALID | ||
Severity: | normal | CC: | aaron.lu, alan, intel-gfx-bugs, lee.joshwa |
Priority: | P1 | ||
Hardware: | All | ||
OS: | Linux | ||
Kernel Version: | 3.14.0-031400rc6 | Subsystem: | |
Regression: | No | Bisected commit-id: | |
Attachments: |
acpidump and dmesg results
acpidump dmesg with 'drm.debug=0xe' as requested |
Description
lee.joshwa
2014-03-17 16:19:33 UTC
Please attach acpidump and dmesg here. Do you always have this problem or it starts to occur from some kernel version? Created attachment 130051 [details]
acpidump and dmesg results
acpidump fails due to missing tables. grogg@envy:~$ acpidump > acpidump.out Cannot open /dev/mem Could not get ACPI tables, AE_ACCESS You need to be root to access /dev/mem Created attachment 130071 [details]
acpidump
My mistake. Here is a complete acpidump...
Do you always have this problem or it starts to occur from some kernel version? This is persistent with all kernel versions. The ACPI dump shows that firmware doesn't provide a video output device that is capable of backlight control, so no chance for ACPI to create a backlight interface. The best bet would be the GPU driver to create a native interface, especially the firmware claims support of windows 8/8.1. Re-assign to GPU/i915. Please provide dmesg with drm.debug=0xe module parameter set. Created attachment 130271 [details]
dmesg with 'drm.debug=0xe' as requested
(In reply to lee.joshwa from comment #10) > Created attachment 130271 [details] > dmesg with 'drm.debug=0xe' as requested So there's an embedded display that is otherwise working when you captured the dmesg? It's an HDMI display, right? What does xrandr say? Correct on both parts. xrandr gives the following: Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 32767 x 32767 VGA1 disconnected (normal left inverted right x axis y axis) HDMI1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 510mm x 287mm 1920x1080 60.0*+ 1600x1200 60.0 1680x1050 59.9 1600x900 60.0 1280x1024 60.0 1440x900 59.9 1280x720 60.0 1024x768 60.0 800x600 60.3 640x480 60.0 720x400 70.1 VIRTUAL1 disconnected (normal left inverted right x axis y axis) So basically you have an external HDMI display in the same all-in-one box. Looking from the outside, it sure looks embedded, but from the hardware and driver perspective it's an external display. It is likely that DDC/CI is used for backlight control. See details in an otherwise unrelated bug [1]. This is not a bug in our driver. [1] https://bugs.freedesktop.org/show_bug.cgi?id=73156#c14 After searching further into what you've just posted I've found that I can control backlight manually using: 'xrandr --output HDMI1 --brightness 1.0' Where '1.0' can be changed between '0.0' and '1.0'. Thank you for looking into this. I suppose I'll need to setup some keyboard shortcuts. (In reply to lee.joshwa from comment #14) > After searching further into what you've just posted I've found that I can > control backlight manually using: > > 'xrandr --output HDMI1 --brightness 1.0' Confirmed with Chris, this just modifies the gamma curves. If it works for you, great, but it doesn't actually modify the backlight brightness. Yes, I understand that. ddccontrol does not seem to be working, and I'm not concerned about power savings. I'm simply looking for functional control of appearance. There is actually a backlight control program in the ubuntu software center that adjusts for xrandr so I'm using it. It's not exactly the fix I was looking for, but it will work. |