2020-11-22T15:13:45
Unable to Change Display Brightness with Intel HD Graphics (i915)
After upgrading to Linux kernel 5.4.0-54-generic, I was unable to adjust my display brightness.
dmesg output shows i915 'Y' invalid for parameter 'enable_dpcd_backlight'
/etc/default/grub contains i915.enable_dpcd_backlight=Y for GRUB_CMDLINE_LINUX_DEFAULT.
Removing the i915.enable_dpcd_backlight=Y from GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub resolved the issue.