register_platform_power_off(9)

Welcome to the Kernel API Manual, bestie 💖 — this is the page for register_platform_power_off(9), and it is literally all about handing the kernel your platform-level power-off callback. no cap.

🌸 NAME 🌸

register_platform_power_off — Register platform-level power-off callback. It’s giving “last-resort shutdown behavior,” and honestly? iconic. 💅

✨ SYNOPSIS ✨

int register_platform_power_off (void (*power_off)(void) );

🎀 ARGUMENTS 🎀

• power_off — Power-off callback. This is the callback that gets registered for power-off duty, and its signature is right there in the synopsis: void (*power_off)(void). 🫶

💅 DESCRIPTION 💅

Okay so here’s the tea: this registers a power_off callback that will be called as the last step of the power-off sequence, bestie. This callback is expected to be invoked for the last resort — like the final-final-final backup plan. No pressure or anything. 😭🔥

Only one platform power-off callback is allowed to be registered at a time. One callback. That’s the whole roster. So don’t be out here trying to register a second one like it’s a group chat; the API said what it said. 💀

Return behavior: it returns 0 on success, or an error code on failure. If you get 0, slay ✨. If you get an error code, read it and handle your business, fr fr. 🫡

👑 SEE ALSO 👑

Kernel file: ./kernel/reboot.c — and the whole friend group is here:

• emergency_restart(9)
• register_reboot_notifier(9)
• unregister_reboot_notifier(9)
• register_restart_handler(9)
• unregister_restart_handler(9)
• do_kernel_restart(9)
• kernel_restart(9)
• kernel_halt(9)
• register_sys_off_handler(9)
• unregister_sys_off_handler(9)
• devm_register_sys_off_handler(9)
• devm_register_power_off_handler(9)
• devm_register_restart_handler(9)
• unregister_platform_power_off(9)
• do_kernel_power_off(9)
• kernel_can_power_off(9)
• kernel_power_off(9)
• orderly_poweroff(9)
• orderly_reboot(9)
• hw_failure_emergency_action_func(9)
• hw_failure_emergency_schedule(9)
• __hw_protection_trigger(9)

mwah 💋 — with love from the ./kernel source, October 2026 edition, aka the register_platform_power_off(9) page. 🫶✨