ddcutil 2.2.2 Release Notes (Preliminary)

05 October 2025

Bug Fixes

Release 2.2.2 contains one significant bug fix of interest to general users:

  • Starting with release 2.2.0, verification on command setvcp and API functions that set a feature value did not not occur, even if option --verify was explicitly given.

Additional bug fixes:

  • Command getvcp --verbose: output was partially in a format intended for syslog.
  • Command environment --verbose:
  • Permission denied errors corrupted output of the find command used to scan for DisplayLink devices.
  • Incorrectly formed path name for examining /sys/class/drm.

Miscellanous changes:

  • Relax the check of the device class when determining if a device is a video controller. Look only at the first byte in sysfs device attribute class. An AMD Ryzen AI 9 365 based system was seen to report 0x038000, not 0x030000. Addresses issue #530.
  • Additional messages reporting configuration file errors. In particular, section names and the names of keys within each section are validated. Section names other than [global], [ddcutil], or [libddcutil] are flagged as errors.
  • If possible, obtain the list of PNP ids from /usr/share/hwdata/pnp.ids instead of using a hardcoded list. Affects output of command detect.
  • Reword the parser explanation of options --verify and --noverify for clarity..
  • Attribute VERIFY can be specified on the ATTRS line in a feature definition file. If included, setvcp verification will never be performed for that feature, without affecting other features. Addresses monitors such as Samsung LS34A650U, which always returns 0 as the value of feature x10 (Brightness) and monitors such as Dell 2407WFP where setvcp x10 values in the range 0..50 are mapped to the range 30..50. In particular, it allows client programs such as KDE PowerDevil succeed in setting a value.

Debug related changes:

  • Added option --trace-to_syslog: Direct trace output to the system log, without disabling other destinations
  • Added option --trcback : Reports the caller stack (within ddcutil) of that function. This option requires that traced function stacks are enabled, which is the default.

Build Fixes:

  • Fix out-of-tree build reference to generated file /src/base/build_details.h. Pull request #544
  • Build failed with an undefined reference error when configure option --disable-drm was specified.
  • configure option --disable-drm forces --disable-watch-displays

For libddcutil related changes, see Shared Library Changes for Release 2.2.2.

For ddcui changes, see ddcui Release Notes

For notes on release 2.2.0 and 2.2.1, see ddcutil 2.2.0 Release Notes. For notes on releases prior to 2.2.0, see Notes for Releases 2.1.4 and Earlier.