ptp_find_pin(9)

ptp_find_pin(9) — the Kernel API Manual, bestie edition 💅✨

okay so this is ptp_find_pin, and it's literally the glow-up you need when you're trying to figure out which pin handles a specific auxiliary function. iconic behavior, no cap. 🎀

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✨ NAME ✨

ptp_find_pin — obtain the pin index of a given auxiliary function 🫶

🌸 SYNOPSIS 🌸

int ptp_find_pin (struct ptp_clock *ptp , enum ptp_pin_function func ,
unsigned int chan );

🦋 ARGUMENTS 🦋

• ptp — the clock you got from ptp_clock_register. your main character struct, basically 👑
• func — one of the ptp_pin_function enumerated values. pick your vibe from the enum 💫
• chan — the particular functional channel to find. yes, the particular one, be specific bestie 🔍

💖 DESCRIPTION 💖

okay so the tea is: the caller must hold ptp_clock::pincfg_mux. that's the rule, fr fr.

and here's the little plot twist 😭 — drivers do not have access to that mutex, because ptp_clock is an opaque type. so you can't just grab it yourself, rude but that's how it is.

but wait, it gets better: the core code acquires the mutex before invoking the driver's ptp_clock_info::enable callback. so drivers may call this function from that context. slay, problem solved ✨

🔥 RETURN 🔥

• pin index in the range of zero to ptp_clock_caps.n_pins - 1 💅
• or -1 if the auxiliary function cannot be found. not found = you get the -1, sorry bestie 😭

🌈 SEE ALSO 🌈

• Kernel file ./include/linux/ptp_clock_kernel.h
• struct ptp_clock_request(9)
• struct ptp_system_timestamp(9)
• struct ptp_clock_info(9)
• struct ptp_clock_event(9)
• scaled_ppm_to_ppb(9)
• diff_by_scaled_ppm(9)
• adjust_by_scaled_ppm(9)
• ptp_clock_register(9)
• ptp_clock_unregister(9)
• ptp_clock_event(9)
• ptp_clock_index(9)
• ptp_clock_index_by_of_node(9)
• ptp_clock_index_by_dev(9)
• ptp_find_pin_unlocked(9)
• ptp_schedule_worker(9)
• ptp_cancel_worker_sync(9)
• ptp_get_vclocks_index(9)
• ptp_convert_timestamp(9)

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and that's the whole vibe check, bestie 🧚💜 this lil page lives over in ./include/linux, dated October 2026, and it's filed under ptp_find_pin(9) — go off, you've got this 🌟🍓