dwc2_next_periodic_start(9)

💅 dwc2_next_periodic_start(9) — the Kernel API Manual page, but make it cute ✨

okay so welcome to the Kernel API Manual entry for dwc2_next_periodic_start(9) — manual name folded right in near the top, bestie 🫶

🌸 NAME 🌸

dwc2_next_periodic_start — Set next_active_frame for next transfer start. 💖

✨ SYNOPSIS ✨

int dwc2_next_periodic_start (struct dwc2_hsotg *hsotg , struct dwc2_qh
       *qh , u16 frame_number );

🎀 ARGUMENTS 🎀

• hsotg — The HCD state structure. That’s the big state baby, no cap 💅
• qh — QH for the periodic transfer. It’s giving queue-head main character energy 🦋
• frame_number — The current frame number. The frame we’re on right now, periodt ⭐

🦋 DESCRIPTION 🦋

So this function is called for setting next_active_frame for a periodic transfer for all cases other than midway through a periodic split. It also updates start_active_frame, because of course it does 💖

Since we always keep start_active_frame as the start of the previous transfer, this is normally pretty easy: we just add our interval to start_active_frame and we’ve got our answer. Slay, honestly ✨

The tricks come into play if we miss. In that case we’ll look for the next slot we can fit into 👀

🔥 RETURN 🔥

Returns the number missed by — or 0 if we didn’t miss. Simple as that, bestie 💀

🌈 SEE ALSO 🌈

• 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_reserve(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_hcd_qtd_init(9)
• dwc2_hcd_qtd_add(9)

that’s the whole page, bestie — source/version: ./drivers/usb/dwc2; date: October 2026. go off, kernel icon 👑💜