drm_atomic_h...r_set_config(9)

drm_atomic_h...r_set_config(9) 🎀

okay bestie, so this is a page from the Kernel API Manual and it's about drm_atomic_helper_set_config — yes the header line is doing that truncated drm_atomic_h...r_set_config(9) thing, that's just how it's printed, don't come for her 💅. Anyway. Sit down, grab a strawberry drink 🍓, and let's talk about setting a new config from userspace.

---

✨ NAME ✨

drm_atomic_helper_set_config — set a new config from userspace. that's it. that's the whole job. 🫶

---

🌸 SYNOPSIS 🌸

int drm_atomic_helper_set_config (struct drm_mode_set *set , struct
drm_modeset_acquire_ctx *ctx );

like, you hand her a struct drm_mode_set *set and a struct drm_modeset_acquire_ctx *ctx, and she gives you back an int. two args, one int, no drama. ✨

---

🦋 ARGUMENTS 🦋

• set — the mode set configuration 💖 this is the actual "here's what I want the screen to look like" bundle.
• ctx — the lock acquisition context 🔒 your proof that you've already handled the locking situation, bestie.

---

👑 DESCRIPTION 👑

So what she actually does: this gives you a default CRTC set_config handler built on the atomic driver interface. like, a ready-made one so you don't have to write your own. iconic behaviour honestly. no cap. 🔥

---

💀 NOTE 💀

okay this part's important, pay attention bestie:

for backwards compatibility with old userspace, this automatically resets the "link-status" property to GOOD, which forces any link re-training. slurp. 💅

and why is that allowed? because the SETCRTC ioctl does not define whether an update needs a full modeset or just a plane update — so she's within her rights to do it. periodt. ✨

see also drm_connector_set_link_status_property. iykyk 🧚

---

🌈 RETURN 🌈

• returns 0 on success 🎉
• returns negative errno numbers on failure 😭 (yes, plural, there are many ways to fail, that's just life)

---

⭐ SEE ALSO ⭐

she has so many friends, honestly main character energy with this contact list 👑 — and it all lives in the kernel file ./drivers/gpu/drm/drm_atomic_helper.c:

• overview(9)
• drm_atomic_helper_check_modeset(9)
• drm_atomic_helper_check_wb_connector_state(9)
• drm_atomic_helper_check_plane_state(9)
• drm_atomic_helper_check_crtc_primary_plane(9)
• drm_atomic_helper_check_planes(9)
• drm_atomic_helper_check(9)
• drm_atomic_helper_commit_encoder_bridge_disable(9)
• drm_atomic_helper_commit_crtc_disable(9)
• drm_atomic_helper_commit_encoder_bridge_post_disable(9)
• drm_atomic_helper_update_legacy_modeset_state(9)
• drm_atomic_helper_calc_timestamping_constants(9)
• drm_atomic_helper_commit_crtc_set_mode(9)
• drm_atomic_helper_commit_modeset_disables(9)
• drm_atomic_helper_commit_writebacks(9)
• drm_atomic_helper_commit_encoder_bridge_pre_enable(9)
• drm_atomic_helper_commit_crtc_enable(9)
• drm_atomic_helper_commit_encoder_bridge_enable(9)
• drm_atomic_helper_commit_modeset_enables(9)
• drm_atomic_helper_wait_for_fences(9)
• drm_atomic_helper_wait_for_vblanks(9)
• drm_atomic_helper_wait_for_flip_done(9)
• drm_atomic_helper_commit_tail(9)
• drm_atomic_helper_commit_tail_rpm(9)
• drm_atomic_helper_async_check(9)
• drm_atomic_helper_async_commit(9)
• drm_atomic_helper_commit(9)
• implementing nonblocking commit(9)
• drm_atomic_helper_setup_commit(9)
• drm_atomic_helper_wait_for_dependencies(9)
• drm_atomic_helper_fake_vblank(9)
• drm_atomic_helper_commit_hw_done(9)
• drm_atomic_helper_commit_cleanup_done(9)
• drm_atomic_helper_prepare_planes(9)
• drm_atomic_helper_unprepare_planes(9)
• drm_atomic_helper_commit_planes(9)
• drm_atomic_helper_commit_planes_on_crtc(9)
• drm_atomic_helper_disable_planes_on_crtc(9)
• drm_atomic_helper_cleanup_planes(9)
• drm_atomic_helper_swap_state(9)
• drm_atomic_helper_update_plane(9)
• drm_atomic_helper_disable_plane(9)
• drm_atomic_helper_disable_all(9)
• drm_atomic_helper_reset_crtc(9)
• drm_atomic_helper_shutdown(9)
• drm_atomic_helper_duplicate_state(9)
• drm_atomic_helper_suspend(9)
• drm_atomic_helper_commit_duplicated_state(9)
• drm_atomic_helper_resume(9)
• drm_atomic_helper_page_flip(9)
• drm_atomic_helper_page_flip_target(9)
• drm_atomic_helper_bridge_propagate_bus_fmt(9)
• drm_atomic_helper_bridge_get_hdmi_output_bus_fmts(9)

---

and that's the whole page, bestie, you ate that 🫶✨

little sign-off before you go: this one's stamped from ./drivers/gpu/drm, dated October 2026 — same code, same page name drm_atomic_h...r_set_config(9), just a whole lot more glitter on it now. bye babe 💖🎀