STANDARD CRTC PROPERTIES(9)

standard CRTC properties 💅

okay so bestie, this is the Kernel API Manual, section 9 — standard CRTC properties(9) — and we're about to make DRM CRTC properties make sense. DRM CRTCs have a few standardized properties, and yes, they're all getting the group-chat treatment. 🎀

✨ the standardized properties ✨

• ACTIVE — Atomic property for setting the power state of the CRTC. When set to 1 the CRTC will actively display content. When set to 0 the CRTC will be powered off. There is no expectation that user-space will reset CRTC resources like the mode and planes when setting ACTIVE to 0. User-space can rely on an ACTIVE change to 1 to never fail an atomic test as long as no other property has changed. If a change to ACTIVE fails an atomic test, this is a driver bug. For this reason setting ACTIVE to 0 must not release internal resources (like reserved memory bandwidth or clock generators). Note that the legacy DPMS property on connectors is internally routed to control this property for atomic drivers. periodt.
• MODE_ID — Atomic property for setting the CRTC display timings. The value is the ID of a blob containing the DRM mode info. To disable the CRTC, user-space must set this property to 0. Setting MODE_ID to 0 will release reserved resources for the CRTC. 🦋
• SCALING_FILTER — Atomic property for setting the scaling filter for CRTC scaler. The value of this property can be one of the following:
  • Default — Driver's default scaling filter.
  • Nearest Neighbor — Nearest Neighbor scaling filter.
• SHARPNESS_STRENGTH — Atomic property for setting the sharpness strength/intensity by userspace. The value of this property is set as an integer value ranging from 0 - 255 where:
  • 0 — Sharpness feature is disabled(default value).
  • 1 — Minimum sharpness.
  • 255 — Maximum sharpness.

User can gradually increase or decrease the sharpness level and can set the optimum value depending on content. This value will be passed to kernel through the UAPI. The setting of this property does not require modeset. The sharpness effect takes place post blending on the final composed output. If the feature is disabled, the content remains same without any sharpening effect and when this feature is applied, it enhances the clarity of the content. ✨

👀 SEE ALSO 👀

• Kernel file ./drivers/gpu/drm/drm_crtc.c overview(9)
• drm_crtc_from_index(9)
• drm_crtc_init_with_planes(9)
• drmm_crtc_init_with_planes(9)
• drm_crtc_cleanup(9)
• drm_mode_getcrtc(9)
• drm_mode_set_config_internal(9)
• drm_crtc_check_viewport(9)
• drm_mode_setcrtc(9)
• drm_crtc_create_scaling_filter_property(9)
• drm_crtc_in_clone_mode(9)

okay that's the whole page, bestie! 🫶 source/version: ./drivers/gpu/drm; date: October 2026; footer title: standard CRTC properties(9). mwah 💋🌸