tty_register_device_attr(9)

Ok bestie, welcome to tty_register_device_attr(9) from the Kernel API Manual — we’re registering a tty device and making it make sense. 💖

🌸 NAME 🌸

tty_register_device_attr — register a tty device, that’s literally the whole gig. 💅

✨ SYNOPSIS ✨

struct device * tty_register_device_attr (struct tty_driver *driver ,
unsigned index , struct device *device , void *drvdata , const struct
attribute_group **attr_grp );

🎀 ARGUMENTS 🎀

• driver — the tty driver that describes the tty device. Main character energy for this call. ✨
• index — the index in the tty driver for this tty device. It’s giving “which one is this?” 🎯
• device — a struct device that is associated with this tty device. This field is optional, bestie: if there is no known struct device for this tty device it can be set to NULL safely. 🫶
• drvdata — Driver data to be set to device. Yes, that’s the whole vibe. 🍓
• attr_grp — Attribute group to be set on device. Slay, attributes. 💅

💅 DESCRIPTION 💅

This call is required to be made to register an individual tty device if the tty driver’s flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If that bit is not set, this function should not be called by a tty driver. No cap, that’s the rule. 🚨

Locking: ??

The manpage literally says Locking: ??, and honestly same. 😭 Keep that caveat exactly as mysterious as it is.

🫶 RETURN 🫶

A pointer to the struct device for this tty device (or ERR_PTR(-EFOO) on error). On error it’s giving ERR_PTR, not “oopsie, try again.” 🔥

🔥 SEE ALSO 🔥

Kernel file ./drivers/tty/tty_io.c is the home base, and the full related-call squad is:

free_tty_struct(9), tty_free_file(9), tty_name(9), get_tty_driver(9),
tty_dev_name_to_number(9), tty_find_polling_driver(9), tty_wakeup(9),
tty_release_redirect(9), __tty_hangup(9), tty_hangup(9), tty_vhangup(9),
tty_vhangup_self(9), tty_vhangup_session(9), tty_hung_up_p(9), stop_tty(9),
start_tty(9), tty_read(9), tty_write(9), tty_send_xchar(9), pty_line_name(9),
tty_line_name(9), tty_driver_lookup_tty(9), tty_init_termios(9),
tty_standard_install(9), tty_driver_install_tty(9), tty_driver_remove_tty(9),
tty_reopen(9), tty_init_dev(9), tty_save_termios(9), tty_flush_works(9),
release_one_tty(9), tty_kref_put(9), release_tty(9), tty_release_checks(9),
tty_kclose(9), tty_release_struct(9), tty_release(9), tty_open_current_tty(9),
tty_lookup_driver(9), tty_kopen_exclusive(9), tty_kopen_shared(9),
tty_open_by_driver(9), tty_open(9), tty_poll(9), tiocsti(9), tiocgwinsz(9),
tty_do_resize(9), tiocswinsz(9), tioccons(9), tiocsetd(9), tiocgetd(9),
send_break(9), tty_get_tiocm(9), tty_tiocmget(9), tty_tiocmset(9),
tty_get_icount(9), alloc_tty_struct(9), tty_put_char(9),
tty_register_device(9), tty_unregister_device(9), __tty_alloc_driver(9),
tty_driver_kref_put(9), tty_register_driver(9), tty_unregister_driver(9)

Bye bestie 🫶 — this one’s from ./drivers/tty, dated October 2026, and it’s literally tty_register_device_attr(9). 👑