usb_hcd_irq(9)

💖 usb_hcd_irq(9) — Kernel API Manual 💖

okay so bestie, welcome to the usb_hcd_irq(9) page from the Kernel API Manual — this is literally the little hook that ties IRQs into the HCD framework, aka the bus glue. 🫶✨

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🎀 NAME 🎀

usb_hcd_irq — hook IRQs to HCD framework (bus glue) 💅

🌸 SYNOPSIS 🌸

the signature is giving:

irqreturn_t usb_hcd_irq (int irq , void *__hcd );

🦋 ARGUMENTS 🦋

• irq — the IRQ being raised ⚡
• __hcd — pointer to the HCD whose IRQ is being signaled 💖

🔥 DESCRIPTION 🔥

okay so here's the tea: if the controller isn't HALTed, it calls the driver's irq handler. then it checks whether the controller is now dead. that's the whole vibe check — no extra lore, no invented drama. 😌

✨ RETURN ✨

• IRQ_HANDLED if the IRQ was handled. ✅
• IRQ_NONE otherwise. ❌

🌈 SEE ALSO 🌈

Kernel file ./drivers/usb/core/hcd.c is the main-character file here, and these are all in the SEE ALSO group chat:

• ascii2desc(9)
• rh_string(9)
• usb_bus_init(9)
• usb_register_bus(9)
• usb_deregister_bus(9)
• register_root_hub(9)
• usb_calc_bus_time(9)
• usb_hcd_link_urb_to_ep(9)
• usb_hcd_check_unlink_urb(9)
• usb_hcd_unlink_urb_from_ep(9)
• usb_hcd_giveback_urb(9)
• usb_hcd_alloc_bandwidth(9)
• usb_hcd_reset_endpoint(9)
• usb_alloc_streams(9)
• usb_free_streams(9)
• usb_hcd_resume_root_hub(9)
• usb_bus_start_enum(9)
• usb_hc_died(9)
• usb_create_shared_hcd(9)
• usb_create_hcd(9)
• usb_stop_hcd(9)
• usb_add_hcd(9)
• usb_remove_hcd(9)

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xoxo, your kernel bestie 💋 — source/version: ./drivers/usb/core, date: October 2026, and this whole page is about usb_hcd_irq(9). slay and stay hydrated 🍓✨