How to turn on the keyboard backlight on a laptop?

I have on my hands an old 2011 Toshiba Qosmio X770 laptop, with CentOS Stream 8 and Windows 7 installed on it. The backlit keyboard works fine under Windows, but it remains dark under Linux. How can I turn on the keyboard backlight on Linux? Both CapsLock and NumLock leds work ok. The Fn+Z key (which commands the keyboard backlight) does nothing. The commands xset led on or xset led off doesn't seem to have any effect. Output of find /sys/devices -iname '*keyboard*' -or -iname '*kbd*' -or -iname '*backlight*': /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/backlight /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/drm/card0/card0-eDP-1/nv_backlight1 /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/drm/card0/card0-LVDS-2/nv_backlight /sys/devices/pci0000:00/0000:00:02.0/backlight /sys/devices/pci0000:00/0000:00:02.0/drm/card1/card1-LVDS-1/intel_backlight Content of /sys/class/leds/: lrwxrwxrwx 1 root root 0 Sep 1 21:39 ath9k-phy0 -> ../../devices/pci0000:00/0000:00:1c.1/0000:03:00.0/leds/ath9k-phy0 lrwxrwxrwx 1 root root 0 Sep 1 2022 input3::capslock -> ../../devices/platform/i8042/serio0/input/input3/input3::capslock lrwxrwxrwx 1 root root 0 Sep 1 2022 input3::numlock -> ../../devices/platform/i8042/serio0/input/input3/input3::numlock lrwxrwxrwx 1 root root 0 Sep 1 2022 input3::scrolllock -> ../../devices/platform/i8042/serio0/input/input3/input3::scrolllock lrwxrwxrwx 1 root root 0 Sep 1 21:39 mmc0:: -> ../../devices/pci0000:00/0000:00:1c.3/0000:05:00.0/leds/mmc0:: EDIT: Output of lsmod | grep acpi: snd_intel_sdw_acpi 16384 1 snd_intel_dspcfg