apple_smc_enter_atomic(9)

🎀 NAME 🎀

okay so bestie, apple_smc_enter_atomic(9) — straight out of the Kernel API Manual — is the function that gets you into atomic mode so you can actually use apple_smc_write_atomic. it’s giving “VIP pass to one specific function,” and i’m obsessed. 💅

✨ SYNOPSIS ✨

int apple_smc_enter_atomic (struct apple_smc *smc );

🫶 ARGUMENTS 🫶

• smc — pointer to apple_smc struct. that’s the one and only argument, bestie. 🦋

💖 DESCRIPTION 💖

so this function switches the SMC backend to atomic mode, which is what lets you use apple_smc_write_atomic. but here’s the catch, and it’s a big one: while you’re in atomic mode, all other functions are disabled. like, all of them. no cap. 💀

it’s only used for shutdown/reboot, because that path needs to write to a SMC key from atomic context. main character energy for a very specific moment, honestly. 👑

heads up: atomic mode is a one-job situation. apple_smc_write_atomic is the only thing on the guest list, and all the other functions are uninvited. 🚫

⭐ RETURN ⭐

Zero on success, negative errno on error. slay when it works, sad little negative number when it doesn’t. 😭

🌈 SEE ALSO 🌈

Kernel file ./include/linux/mfd/macsmc.h, plus the whole squad:

• smc_key(9)
• SMC_KEY(9)
• struct apple_smc_key_info(9)
• enum apple_smc_boot_stage(9)
• struct apple_smc(9)
• apple_smc_read(9)
• apple_smc_write(9)
• apple_smc_write_atomic(9)
• apple_smc_rw(9)
• apple_smc_get_key_by_index(9)
• apple_smc_get_key_info(9)
• apple_smc_key_exists(9)

mwah 💋 — this cutie comes from source/version ./include/linux/mfd, dated October 2026. 🍓🧚💜