uart_handle_dcd_change(9)

💖 NAME 💖

uart_handle_dcd_change — bestie, this is the one that handles a change of carrier detect state ✨ (yes, that DCD, the modem line, the whole vibe check of "is somebody actually on the other end of this wire")

🌸 SYNOPSIS 🌸

void uart_handle_dcd_change (struct uart_port *uport , bool active );

🎀 ARGUMENTS 🎀

• uport — the uart_port structure for the open port 🫶 like, the port that's actually up and running, not some random one you fished out of a drawer.
• active — the new carrier detect status 💅 the fresh DCD value, handed to you like a lil' boo-boo update.

✨ DESCRIPTION ✨

Okay so real talk: the caller must hold uport->lock 🔒 no cap. That's the whole deal. You're the caller, you bring the lock, that's the entry fee. Don't show up unlocked, it's giving chaos 😭

🦋 SEE ALSO 🦋

Kernel file ./drivers/tty/serial/serial_core.c — the source of truth, go read it, it ate 👑

• uart_write_wakeup(9)
• 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_cts_change(9)
• uart_insert_char(9)
• uart_try_toggle_sysrq(9)
• uart_get_rs485_mode(9)

That's the whole page, bestie, you're so welcome 💜 And for the sign-off: this lil' baddie lives in ./drivers/tty/serial, it's dated October 2026, and it came to you courtesy of the Kernel API Manual 🧚⭐ Go forth and handle those carrier detect changes responsibly, mwah 🍓