usb_gadget_...nc_callbacks(9)

💖 usb_gadget_enable_async_callbacks(9) — a Kernel API Manual page 💖

okay so this is from the Linux Kernel API Manual, section 9, and the function is usb_gadget_enable_async_callbacks. yes the header line up top was like usb_gadget_...nc_callbacks(9) because it got truncated, iconic of it honestly. let's get into it bestie 🫶

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✨ NAME ✨

usb_gadget_enable_async_callbacks — the one where you tell the usb device controller "hey, go ahead and turn the asynchronous callbacks back on" 💅

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🌸 SYNOPSIS 🌸

void usb_gadget_enable_async_callbacks (struct usb_udc *udc );

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🎀 ARGUMENTS 🎀

• udc — the UDC that should enable async callbacks. yeah. that's the one. give it the good news 💌

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🦋 DESCRIPTION 🦋

so this routine is what you call when you're binding gadget drivers. it literally undoes the effect of usb_gadget_disable_async_callbacks — like a little reverse card 🃏 — and when it runs, the UDC driver should enable IRQs (if necessary, no pressure) and resume issuing callbacks. back in business, we love a comeback arc ✨

and ngl, this routine will always be called in process context. always. no exceptions, no cap. so don't be out here thinking you can call it from some wild interrupt context 🙈

no tricky threading shenanigans here bestie — process context, every single time. periodt.

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💜 SEE ALSO 💜

the whole friend group, fr fr. go say hi:

• Kernel file ./drivers/usb/gadget/udc/core.c
• struct usb_udc(9)
• usb_ep_set_maxpacket_limit(9)
• usb_ep_enable(9)
• usb_ep_disable(9)
• usb_ep_alloc_request(9)
• usb_ep_free_request(9)
• usb_ep_queue(9)
• usb_ep_dequeue(9)
• usb_ep_set_halt(9)
• usb_ep_clear_halt(9)
• usb_ep_set_wedge(9)
• usb_ep_fifo_status(9)
• usb_ep_fifo_flush(9)
• usb_gadget_frame_number(9)
• usb_gadget_wakeup(9)
• usb_gadget_set_remote_wakeup(9)
• usb_gadget_set_selfpowered(9)
• usb_gadget_clear_selfpowered(9)
• usb_gadget_vbus_connect(9)
• usb_gadget_vbus_draw(9)
• usb_gadget_vbus_disconnect(9)
• usb_gadget_connect(9)
• usb_gadget_disconnect(9)
• usb_gadget_deactivate(9)
• usb_gadget_activate(9)
• usb_gadget_giveback_request(9)
• gadget_find_ep_by_name(9)
• usb_gadget_check_config(9)
• usb_udc_vbus_handler(9)
• usb_gadget_udc_reset(9)
• usb_gadget_udc_start_locked(9)
• usb_gadget_udc_stop_locked(9)
• usb_gadget_udc_set_speed(9)
• usb_gadget_disable_async_callbacks(9) ← the ex, the one this one undoes 💔
• usb_udc_release(9)
• usb_initialize_gadget(9)
• usb_add_gadget(9)
• usb_add_gadget_udc_release(9)
• usb_get_gadget_udc_name(9)
• usb_add_gadget_udc(9)
• usb_del_gadget(9)
• usb_del_gadget_udc(9)

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and that's the whole page, bestie!! 💖 little sign-off moment: this one lives in the source tree at ./drivers/usb/gadget/udc, and it's dated October 2026 in the Kernel API Manual. slay, see u in the next manpage 👑✨🎀