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slug001

Member

Registered: 2024-12-13

Posts: 26

Display doesn't react to brightness buttons on laptop

My VAIO laptop has brightness controls, volume controls, a programmable button etc. Volume controls work fine, battery level gets shown correctly. The brightness controls show up correctly in GNOME, /sys/class/backlight/sony/brightness gets modified, but no changes on the screen. below i attach acpi_listen logs. one button press sends a brightness up/down signal and two sony signals.

video/brightnessdown BRTDN 00000087 00000000 K
sony/hotkey SNY5001:00 00000001 00000010
sony/hotkey SNY5001:00 00000001 0000003b
video/brightnessup BRTUP 00000086 00000000 K
sony/hotkey SNY5001:00 00000001 00000011
sony/hotkey SNY5001:00 00000001 0000003b

my laptop came preinstalled with Windows 7, so i've set acpi_osi to 'Windows 2009', i've also tried 'Linux', but no change. is it possible to map these signal to xorg-xbacklight somehow?

edit1: i checked xev and only this gets displayed, i think it looks the same for both buttons

MappingNotify event, serial 44, synthetic NO, window 0x0,
    request MappingKeyboard, first_keycode 8, count 248

FocusOut event, serial 44, synthetic NO, window 0x2000001,
    mode NotifyGrab, detail NotifyAncestor

FocusIn event, serial 45, synthetic NO, window 0x2000001,
    mode NotifyUngrab, detail NotifyAncestor

KeymapNotify event, serial 45, synthetic NO, window 0x0,
    keys:  2   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
           0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0

Last edited by slug001 (2024-12-16 20:42:18)

yataro

Member

Registered: 2024-03-09

Posts: 93

Re: Display doesn't react to brightness buttons on laptop

Have you tried to specify acpi_backlight kernel parameter?