#1 intel_reg breaks backlight control (Fn-Home/End)

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opened 2 years ago by Ghost · 4 comments
Ghost commented 2 years ago

Offending documentation

Writing values to the register breaks backlight control - i.e., using the Function keys to invoke XF86MonBrightnessUp and XF86MonBrightnessDown (see xev, Function Keys)

Writing to the appropriate /sys/class file still works:

echo '13' | sudo tee /sys/class/backlight/acpi_video0/brightness

Issue fixed by disabling boot and sleep services.

Using a ThinkPad T400 on 20210522.

[Offending documentation](https://libreboot.org/docs/misc/#finetune-backlight-control-on-intel-gpus) Writing values to the register breaks backlight control - i.e., using the Function keys to invoke `XF86MonBrightnessUp` and `XF86MonBrightnessDown` (see `xev`, [Function Keys](https://wiki.archlinux.org/title/Lenovo_ThinkPad_T400#Function_keys)) Writing to the appropriate `/sys/class` file still works: `echo '13' | sudo tee /sys/class/backlight/acpi_video0/brightness` Issue fixed by disabling boot and sleep services. Using a ThinkPad T400 on 20210522.
Ghost commented 2 years ago
Poster
Implicitly, it appears [pulse width modulation detection was fixed upstream](https://teddit.net/r/libreboot/comments/7dt2l5/x200_ccfl_permanent_backlight_fix/dqlp9gp/#c).
Leah Rowe commented 2 years ago
Owner

Can you fix the documentation yourself? Then you can submit a pull request

Can you fix the documentation yourself? Then you can submit a pull request
Ghost commented 2 years ago
Poster

Done in #2

Done in #2
Leah Rowe commented 1 year ago
Owner

can you please re-submit the fix to the docs

can you please re-submit the fix to the docs
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