drm_fb_helper_hotplug_event(9)

💖 drm_fb_helper_hotplug_event(9) 💖

okay so this is the Kernel API Manual page for drm_fb_helper_hotplug_event, and bestie it is literally the “new screen just showed up, let’s figure out the vibe” function. no cap.

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🌸 NAME 🌸

drm_fb_helper_hotplug_event — respond to a hotplug notification by probing all the outputs attached to the fb. 💅

✨ SYNOPSIS ✨

int drm_fb_helper_hotplug_event (struct drm_fb_helper *fb_helper );

🎀 ARGUMENTS 🎀

• fb_helper — driver-allocated fbdev helper, can be NULL. 🙈 yes really, NULL is allowed.

🦋 DESCRIPTION 🦋

Scan the connectors attached to the fb_helper and try to put together a setup after notification of a change in output configuration. it’s giving “new monitor energy” but make it kernel. ✨

Called at runtime, takes the mode config locks to be able to check/change the modeset configuration.

🚨 real talk: must be run from process context (which usually means either the output polling work or a work item launched from the driver’s hotplug interrupt). don’t be weird about it.

Note that drivers may call this even before calling drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows for a race-free fbcon setup and will make sure that the fbdev emulation will not miss any hotplug events. iconic, honestly. 🫶

🔥 RETURN 🔥

0 on success and a non-zero error code otherwise. periodt. 💯

🌈 SEE ALSO 🌈

Kernel file ./drivers/gpu/drm/drm_fb_helper.c, plus the whole fbdev helpers(9) friend group — go read these, iykyk:

• drm_fb_helper_restore_fbdev_mode_unlocked(9)
• drm_fb_helper_blank(9)
• drm_fb_helper_prepare(9)
• drm_fb_helper_unprepare(9)
• drm_fb_helper_init(9)
• drm_fb_helper_unregister_info(9)
• drm_fb_helper_fini(9)
• drm_fb_helper_deferred_io(9)
• drm_fb_helper_set_suspend(9)
• drm_fb_helper_set_suspend_unlocked(9)
• drm_fb_helper_setcmap(9)
• drm_fb_helper_ioctl(9)
• drm_fb_helper_check_var(9)
• drm_fb_helper_set_par(9)
• drm_fb_helper_pan_display(9)
• drm_fb_helper_fill_info(9)
• drm_fb_helper_initial_config(9)
• drm_fb_helper_gem_is_fb(9)

okay bestie, that’s the whole page — signing off from ./drivers/gpu/drm, October 2026, on drm_fb_helper_hotplug_event(9). mwah 💋✨