hsi_event(9)

💅 hsi_event(9) — like, the kernel API manual bestie ✨

okay so real talk, the manual name here is hsi_event and it lives in section 9, so if you see hsi_event(9) floating around in a doc, that's this page, bestie 🫶

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🌸 NAME 🌸

hsi_event — notifies clients about port events 💌 literally its whole job

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✨ SYNOPSIS ✨

int hsi_event (struct hsi_port *port , unsigned long event );

that's it, that's the signature, no cap 💅

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🎀 ARGUMENTS 🎀

• port — the port where the event occurred, i.e. the main character of this call 👑
• event — the event type, so you know which vibe we're dealing with

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🦋 DESCRIPTION 🦋

so listen bestie, here's the situation: clients should not be concerned about wake line behavior. like, that's not your problem, don't stress 💆

but — and this is the important part — there's a race condition in the HSI HW protocol 😭 so clients do need to be notified about wake line changes, so they can implement a workaround for it. it's giving "we know, we know, just roll with it" energy fr fr.

Events: ✨

• HSI_EVENT_START_RX — incoming wake line high 📈
• HSI_EVENT_STOP_RX — incoming wake line down 📉

Returns -errno on error, or 0 on success. slay 🎀

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🔥 SEE ALSO 🔥

kernel file ./drivers/hsi/hsi_core.c — plus the whole friend group, iykyk:

• hsi_port_unregister_clients(9)
• hsi_unregister_controller(9)
• hsi_register_controller(9)
• hsi_register_client_driver(9)
• hsi_put_controller(9)
• hsi_alloc_controller(9)
• hsi_free_msg(9)
• hsi_alloc_msg(9)
• hsi_async(9)
• hsi_claim_port(9)
• hsi_release_port(9)
• hsi_register_port_event(9)
• hsi_unregister_port_event(9)
• hsi_get_channel_id_by_name(9)

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ok that's the whole page bestie, go forth and register your port events responsibly 💜

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and that's a wrap!! this iconic lil page came out of ./drivers/hsi and it's dated October 2026 — periodt ✨🦋🍓