dwc2_do_reserve(9)

💅 dwc2_do_reserve(9) — Kernel API Manual 🎀

okay so bestie, welcome to the kernel API manual page for dwc2_do_reserve(9). it's a whole thing, but i gotchu 🫶

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✨ NAME ✨

dwc2_do_reserve — Make a periodic reservation 💖

like, reserving a slot. in a schedule. for USB stuff. iconic behavior honestly.

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🌸 SYNOPSIS 🌸

int dwc2_do_reserve (struct dwc2_hsotg *hsotg , struct dwc2_qh *qh );

she takes two args and returns an int. that's the whole vibe check ✅

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🦋 ARGUMENTS 🦋

• hsotg — the HCD state structure for the DWC OTG controller. yes it's a whole struct, no you don't get to skip it 💅
• qh — the QH for the periodic transfer. our main character for this function fr fr 👑

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💜 DESCRIPTION 💜

so what does she actually do? she tries to allocate space in the periodic schedule ✨

and here's the fun part — depending on the parameters, this might use the microframe scheduler or the dumb scheduler. two schedulers. two vibes. iykyk 😌

ngl the name "dumb scheduler" is sending me but it's literally what the manpage says so we're keeping it 💀

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⭐ RETURN ⭐

• 0 upon success 🎉
• error upon failure 😭

that's it. that's the return section. slay.

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🌈 SEE ALSO 🌈

buckle up bestie, this list is long — but she ate and we're listing every single one 🍓

• the kernel file ./drivers/usb/dwc2/hcd_queue.c
• dwc2_periodic_channel_available(9)
• dwc2_check_periodic_bandwidth(9)
• pmap_schedule(9)
• pmap_unschedule(9)
• dwc2_get_ls_map(9)
• dwc2_qh_print(9)
• dwc2_qh_schedule_print(9)
• dwc2_ls_pmap_schedule(9)
• dwc2_ls_pmap_unschedule(9)
• dwc2_hs_pmap_schedule(9)
• dwc2_hs_pmap_unschedule(9)
• dwc2_uframe_schedule_split(9)
• dwc2_uframe_schedule_hs(9)
• dwc2_uframe_schedule_ls(9)
• dwc2_uframe_schedule(9)
• dwc2_uframe_unschedule(9)
• dwc2_pick_first_frame(9)
• dwc2_do_unreserve(9)
• dwc2_unreserve_timer_fn(9)
• dwc2_check_max_xfer_size(9)
• dwc2_schedule_periodic(9)
• dwc2_deschedule_periodic(9)
• dwc2_wait_timer_fn(9)
• dwc2_qh_init(9)
• dwc2_hcd_qh_create(9)
• dwc2_hcd_qh_free(9)
• dwc2_hcd_qh_add(9)
• dwc2_hcd_qh_unlink(9)
• dwc2_next_for_periodic_split(9)
• dwc2_next_periodic_start(9)
• dwc2_hcd_qtd_init(9)
• dwc2_hcd_qtd_add(9)

like i said. all of them. no cap 🧚

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okay that's the whole page bestie!! 💖 this one lives in ./drivers/usb/dwc2 and it's dated October 2026 — so yeah, from the future (or at least from the dwc2 docs), mwah 💋 see you in the next SEE ALSO rabbit hole 🦋✨