ep_is_empty(9)

🎀 ep_is_empty(9) 🎀

okay so bestie, welcome to ep_is_empty(9) from the Kernel API Manual — it’s the tiny endpoint vibe check that tells you if ep has byte ready for reading. it’s giving “is there tea in this FIFO or not” energy, and honestly? iconic 💅

✨ NAME ✨

ep_is_empty — checks if ep has byte ready for reading

📜 SYNOPSIS 📜

int ep_is_empty (struct pxa_ep *ep );

🫶 ARGUMENTS 🫶

• ep — udc endpoint

💖 DESCRIPTION 💖

if ep is the control endpoint, this checks if there are bytes in the control endpoint fifo. if ep is a data endpoint, this checks if bytes are ready for reading on the OUT endpoint.

it returns 0 if ep is not empty, 1 if ep is empty, and -EOPNOTSUPP if IN endpoint. that’s the whole little status report, no cap ✨

🌈 SEE ALSO 🌈

kernel file: ./drivers/usb/gadget/udc/pxa27x_udc.c — and here’s the whole bestie lineup:

• is_match_usb_pxa(9)
• find_pxa_ep(9)
• update_pxa_ep_matches(9)
• pio_irq_enable(9)
• pio_irq_disable(9)
• udc_set_mask_UDCCR(9)
• udc_clear_mask_UDCCR(9)
• ep_write_UDCCSR(9)
• ep_count_bytes_remain(9)
• ep_is_full(9)
• epout_has_pkt(9)
• set_ep0state(9)
• ep0_idle(9)
• inc_ep_stats_reqs(9)
• inc_ep_stats_bytes(9)
• pxa_ep_setup(9)
• pxa_eps_setup(9)
• pxa_ep_alloc_request(9)
• pxa_ep_free_request(9)
• ep_add_request(9)
• ep_del_request(9)
• req_done(9)
• ep_end_out_req(9)
• ep0_end_out_req(9)
• ep_end_in_req(9)
• ep0_end_in_req(9)
• nuke(9)
• read_packet(9)
• write_packet(9)
• read_fifo(9)
• write_fifo(9)
• read_ep0_fifo(9)
• write_ep0_fifo(9)
• pxa_ep_queue(9)
• pxa_ep_dequeue(9)
• pxa_ep_set_halt(9)
• pxa_ep_fifo_status(9)
• pxa_ep_fifo_flush(9)
• pxa_ep_enable(9)
• pxa_ep_disable(9)
• dplus_pullup(9)
• pxa_udc_get_frame(9)
• pxa_udc_wakeup(9)
• should_enable_udc(9)
• should_disable_udc(9)
• pxa_udc_pullup(9)
• pxa_udc_vbus_session(9)
• pxa_udc_vbus_draw(9)
• pxa_udc_phy_event(9)
• udc_disable(9)
• udc_init_data(9)
• udc_enable(9)
• pxa27x_udc_start(9)
• stop_activity(9)
• pxa27x_udc_stop(9)
• handle_ep0_ctrl_req(9)
• handle_ep0(9)
• handle_ep(9)
• pxa27x_change_configuration(9)
• pxa27x_change_interface(9)
• irq_udc_suspend(9)
• irq_udc_resume(9)
• irq_udc_reconfig(9)
• irq_udc_reset(9)
• pxa_udc_irq(9)
• pxa_udc_probe(9)
• pxa_udc_remove(9)
• pxa_udc_suspend(9)
• pxa_udc_resume(9)

okay that’s the page! source path is ./drivers/usb/gadget/udc, date is October 2026, and the star of the show is ep_is_empty(9) — periodt, bye bestie 💖🦋