freq_in_rule_band(9)

💖 freq_in_rule_band(9) 💖

okay bestie so you found yourself in the Kernel API Manual and the page in question is freq_in_rule_band(9) — yes that's the whole name, it's giving very "function that knows things" energy and honestly? it does.

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✨ NAME ✨

freq_in_rule_band — literally just tells us if a frequency is in a frequency band 🎀

✨ SYNOPSIS ✨

bool freq_in_rule_band (const struct ieee80211_freq_range *freq_range ,
u32 freq_khz );

✨ ARGUMENTS ✨

• freq_range — the frequency rule we want to query 👀 like, this is the rule we're interrogating
• freq_khz — the frequency we are inquiring about 🫶 the one we're holding up to the light going "do you belong here or not"

✨ DESCRIPTION ✨

so what this does is let us know if a specific frequency rule is or is not relevant to a specific frequency's band. that's it, that's the whole vibe check 💅

now, bands are device specific and honestly kind of artificial definitions — we're talking the "2.4 GHz band", the "5 GHz band" and the "60GHz band" (yes, no space in that last one, that's how it's written, don't come for me 😭).

however — and this is the important part, bestie, don't skip it — it is safe for now to assume that a frequency rule should not be part of a frequency's band if the start freq or end freq are off by more than 2 GHz for the 2.4 and 5 GHz bands, and by more than 20 GHz for the 60 GHz band.

ngl this resolution can be lowered, and it should be considered as we add regulatory rule support for other "bands". so like. keep that in mind for later ✨

✨ RETURN ✨

whether or not the frequency is in the range — a bool, iconic, no notes 💖

✨ SEE ALSO ✨

• Kernel file ./net/wireless/reg.c Wireless regulatory infrastructure(9)
• enum reg_request_treatment(9)
• regdom_intersect(9)
• reg_process_hint_core(9)
• reg_process_hint_user(9)
• reg_process_hint_driver(9)
• reg_process_hint_country_ie(9)

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and that's the page!! 🌸 this little legend lives over in ./net/wireless and the version/date stamp on it says October 2026 — so yeah, mark your calendar bestie, go off, read the source, slay 💜🦋

mwah 💋