drm_rotation_simplify(9)

okay so bestie, welcome to the drm_rotation_simplify(9) page from the Kernel API Manual — manual name folded in right here like a lil ribbon 🎀. This one is all about taking a rotation and trying to simplify it into a form the hardware actually supports, and it is lowkey iconic for that. 💅

🌸 NAME 🌸

• drm_rotation_simplify — Try to simplify the rotation ✨

✨ SYNOPSIS ✨

here’s the signature, copied exactly so nobody comes for me:

unsigned int drm_rotation_simplify (unsigned int rotation , unsigned int
       supported_rotations );

🎀 ARGUMENTS 🎀

• rotation — Rotation to be simplified. That’s the one you’re trying to glow-up. 💖
• supported_rotations — Supported rotations. The set your hardware can actually serve. 👑

🦋 DESCRIPTION 🦋

Attempt to simplify the rotation to a form that is supported. e.g. if the hardware supports everything except DRM_MODE_REFLECT_X, one could call this function like this:

drm_rotation_simplify(rotation, DRM_MODE_ROTATE_0 | DRM_MODE_ROTATE_90 |
       DRM_MODE_ROTATE_180 | DRM_MODE_ROTATE_270 | DRM_MODE_REFLECT_Y);

to eliminate the DRM_MODE_REFLECT_X flag. So yeah, it’s giving “make it fit the supported list” energy. 🌈

⚠️ important bestie: depending on what kind of transforms the hardware supports, this function may not be able to produce a supported transform, so the caller should check the result afterwards. No cap, check that result. 💀

🔥 SEE ALSO 🔥

the whole squad of related kernel docs, fr fr:

• Kernel file ./drivers/gpu/drm/drm_blend.c overview(9)
• drm_plane_create_alpha_property(9)
• drm_plane_create_rotation_property(9)
• drm_plane_create_zpos_property(9)
• drm_plane_create_zpos_immutable_property(9)
• drm_atomic_normalize_zpos(9)
• drm_plane_create_blend_mode_property(9)
• drm_crtc_attach_background_color_property(9)

later, bestie 🫶 — source/version: ./drivers/gpu/drm; date: October 2026. drm_rotation_simplify(9) out. 💖✨