BASIC ANI OPERATION(9)

💅 Basic ANI Operation — section 9, from the Kernel API Manual

okay bestie, pull up a chair, because we're about to talk about Adaptive Noise Immunity and honestly? she's kind of iconic.

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✨ NAME ✨

Basic ANI Operation — like, the whole entire vibe of Adaptive Noise Immunity, explained. It's manual section 9, from the Kernel API Manual. 🎀

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🌸 DESCRIPTION 🌸

okay so Adaptive Noise Immunity (everyone calls her ANI, iykyk) is this girl who watches five noise immunity parameters and adjusts them depending on how much interference is happening in the environment. Like, if it's getting loud in there she pumps the numbers up, and when things calm down she eases off — increasing or reducing sensitivity as necessary. main character energy fr fr. 💅

the five parameters she's obsessed with are:

• "noise immunity"
• "spur immunity"
• "firstep level"
• "OFDM weak signal detection"
• "CCK weak signal detection"

basically (and I cannot stress this enough), we look at the amount of ODFM and CCK timing errors we're getting, and then we raise or lower immunity accordingly by setting one or more of those parameters. that's the whole tea. 🍓

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🦋 how the error counting actually goes down 🦋

so the newer chipsets are the lucky ones — they have PHY error counters in hardware, and those babies will generate a MIB interrupt when they overflow. slay. hardware doing the work so nobody else has to. ✨

the older hardware, though? 😭 she has to enable PHY error frames by setting a RX flag, and then count every single PHY error one by one. exhausting behavior, honestly, but we respect her.

and then: when a specified threshold of errors has been reached, we raise immunity. 🫶 also we regularly check the amount of errors and lower or raise immunity as necessary — so it's not just a one-time thing, she's constantly checking in. lowkey a vibe check but for radio noise.

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👑 SEE ALSO 👑

• Kernel file: ./drivers/net/wireless/ath/ath5k/ani.c

and the whole friend group, in order:

• ath5k_ani_set_noise_immunity_level(9)
• ath5k_ani_set_spur_immunity_level(9)
• ath5k_ani_set_firstep_level(9)
• ath5k_ani_set_ofdm_weak_signal_detection(9)
• ath5k_ani_set_cck_weak_signal_detection(9)
• ath5k_ani_raise_immunity(9)
• ath5k_ani_lower_immunity(9)
• ath5k_hw_ani_get_listen_time(9)
• ath5k_ani_save_and_clear_phy_errors(9)
• ath5k_ani_period_restart(9)
• ath5k_ani_calibration(9)
• ath5k_ani_mib_intr(9)
• ath5k_ani_phy_error_report(9)
• ath5k_enable_phy_err_counters(9)
• ath5k_disable_phy_err_counters(9)
• ath5k_ani_init(9)
• ath5k_ani_print_counters(9)

not me listing all seventeen of them 💀 every single one made the cut, no cap.

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ngl this whole page lives at ./drivers/net/wireless/ath/ath5k, and it's dated October 2026 — so like, mark your calendar bestie, the source and the date are right there. 🧚‍♀️

k that's it, go read ani.c and stan ANI properly. mwah. 💖🔥