Display brightness control not working in 17.10

I just upgraded to ubuntu 17.10 and now display brightness controls are not working, and i am not able to change display brightness at all. But it was working perfectly in 17.04

I also tried this method, but still not working. When I saw system details, it shows unknown graphics.

Section "Device"
        Identifier  "card0"
        Driver      "intel"
        Option      "Backlight"  "intel_backlight"
        BusID       "PCI:0:2:0"
EndSection

What can I do now?

Solution 1:

1. Open a terminal by pressing Ctrl+Alt+T

2. Edit the /etc/default/grub file by running:

   sudo nano /etc/default/grub
   

3. Change the GRUB_CMDLINE_LINUX_DEFAULT line to:

   GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor acpi_osi=Linux"
   

4. Press Ctrl+O to save

5. Press Ctrl+X to exit

6. Update GRUB by running:

   sudo update-grub
   

7. Reboot