Adding i915.enable_dpcd_backlight=3

Hi there. Brightness is on max and cannot be changed in my samsung galaxy book2. adding i915.enable_dpcd_backlight=3 as boot parameter after entering e in boot menu makes it work but it is not permanent. How can i make this change permanent in CL.

The following snippet creates a folder if missing and adds a kernel parameter file. The clr-boot-manager command updates the boot directory.

sudo mkdir -p /etc/kernel/cmdline.d
sudo tee "/etc/kernel/cmdline.d/i915.conf" >/dev/null <<'EOF'
i915.enable_dpcd_backlight=3
EOF
sudo clr-boot-manager update

Thankx @marioroy . will try that.