How to turn on keyboard backlight?

Question

linux

localhost mars # lspci -k
00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: ivb_uncore
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor PCI Express Root Port (rev 09)
Kernel driver in use: pcieport
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: i915
Kernel modules: i915
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: xhci_hcd
Kernel modules: xhci_pci
00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: ehci-pci
Kernel modules: ehci_pci
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)
Subsystem: ASUSTeK Computer Inc. 7 Series/C210 Series Chipset Family High Definition Audio Controller
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel
00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)
Kernel driver in use: pcieport
00:1c.1 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 (rev c4)
Kernel driver in use: pcieport
00:1c.3 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 4 (rev c4)
Kernel driver in use: pcieport
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: ehci-pci
Kernel modules: ehci_pci
00:1f.0 ISA bridge: Intel Corporation HM76 Express Chipset LPC Controller (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: ahci
Kernel modules: ahci
00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel modules: i2c_i801
01:00.0 VGA compatible controller: NVIDIA Corporation GK107M [GeForce GT 650M] (rev a1)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel modules: nvidia
03:00.0 Network controller: Qualcomm Atheros AR9485 Wireless Network Adapter (rev 01)
Subsystem: AzureWave AR9485 Wireless Network Adapter
Kernel driver in use: ath9k
Kernel modules: ath9k
04:00.0 Ethernet controller: Qualcomm Atheros AR8161 Gigabit Ethernet (rev 10)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: alx
Kernel modules: alx

Answer 1

In /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="
try to specify.
And check that the asus_nb_wmi module is loaded