Wiki:
Поддержка ОС для DDC / CI
Несмотря на его повсеместное распространение на дисплеях после 2016 года, DDC / CI обычно не используется операционной системой по умолчанию для управления яркостью на внешних дисплеях. Для отправки команд на дисплей можно использовать дополнительное программное обеспечение, но степень интеграции системы может быть разной. Windows предоставляет DDC / CI как серию Win32 API конфигурации монитора .
https://docs.microsoft.com/en-us/previous-versions/windows/hardware/design/dn613889(v=vs.85)?redirectedfrom=MSDNIntel:
The Intel® Graphics Drivers support the VESA Display Data Channel/Command Interface (DDC/CI) across a DVI, HDMI*, VGA, or DisplayPort* connection.
To access DDC/CI, third-party applications will need to use the Intel graphics driver's API (Application Programming Interface) functions via the driver's CUI SDK (Common User Interface Software Development Kit). The driver's API functions and SDK are not publicly available content and are for developers use only. To request access to the Intel graphics driver's API Specification and CUI SDK, an application's developer should contact their Intel sales representative for assistance or request assistance from their motherboard manufacturer, computer manufacturer, or an Intel® Authorized Distributor.
On Windows Vista* and Windows 7* operating systems, third-party applications may access DDC/CI using either the Intel graphics driver's API functions via the Intel CUI SDK or using the operating system's Monitor Configuration API functions via the Windows* SDK. These operating system API functions are new to Windows Vista and Windows 7 and are not supported in previous versions of Windows.
If your application is having difficulty accessing DDC/CI via a DisplayPort connection, please use the latest graphics driver.
Nvidia:
VESA DDC/CI
interface: the dpaux debugfs to directly communicate with kernel. If you know how ddcutil is implemented, then maybe you can write similar tool for debugfs too.
And besides DDC/CI, currently there is no other method to configure DP brightness on jetson either. (linux)
Amd -