uart_write_wakeup(9)

uart_write_wakeup(9) 🦋

okay so welcome to the Kernel API Manual, bestie — this is the page for uart_write_wakeup, and it's lowkey iconic in the serial-driver world. let's get into it 💖

🌸 NAME 🌸

uart_write_wakeup — schedule write processing. that's the whole name, and it's literally giving "wake up and handle the write side" energy ✨

✨ SYNOPSIS ✨

void uart_write_wakeup (struct uart_port *port );

🎀 ARGUMENTS 🎀

• port — port to be processed. that's the argument, bestie: the struct uart_port * you're handing over so it can be processed 💅

💅 DESCRIPTION 💅

this routine is used by the interrupt handler to schedule processing in the software interrupt portion of the driver. so the interrupt handler is like "hey, let's schedule this work for the software interrupt part of the driver" — and uart_write_wakeup is the function that does exactly that 🫶

a driver is expected to call this function when the number of characters in the transmit buffer have dropped below a threshold. that's the cue, no cap: transmit buffer count goes below the threshold, driver calls this routine 🔥

Locking: port->lock should be held. like, the manual is very clear about this one — hold that lock, bestie, don't just vibe past it 😭💀

🔥 SEE ALSO 🔥

the kernel file ./drivers/tty/serial/serial_core.c is the main character here, and the whole linked-page squad is:

• uart_update_timeout(9)
• uart_get_baud_rate(9)
• uart_get_divisor(9)
• uart_get_lsr_info(9)
• uart_console_write(9)
• uart_parse_earlycon(9)
• uart_parse_options(9)
• uart_set_options(9)
• uart_change_pm(9)
• uart_register_driver(9)
• uart_unregister_driver(9)
• serial_core_add_one_port(9)
• serial_core_remove_one_port(9)
• uart_match_port(9)
• uart_handle_dcd_change(9)
• uart_handle_cts_change(9)
• uart_insert_char(9)
• uart_try_toggle_sysrq(9)
• uart_get_rs485_mode(9)

mwah 💋 this lil page comes from ./drivers/tty/serial, dated October 2026, and it's the uart_write_wakeup(9) manual page — bye bestie, go hold that lock 🎀💖