diff options
Diffstat (limited to 'drivers/char/tty_ioctl.c')
-rw-r--r-- | drivers/char/tty_ioctl.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c index 851cfcd2702..d769e43f73f 100644 --- a/drivers/char/tty_ioctl.c +++ b/drivers/char/tty_ioctl.c @@ -756,6 +756,32 @@ static int send_prio_char(struct tty_struct *tty, char ch) } /** + * tty_change_softcar - carrier change ioctl helper + * @tty: tty to update + * @arg: enable/disable CLOCAL + * + * Perform a change to the CLOCAL state and call into the driver + * layer to make it visible. All done with the termios mutex + */ + +static int tty_change_softcar(struct tty_struct *tty, int arg) +{ + int ret = 0; + int bit = arg ? CLOCAL : 0; + struct ktermios old = *tty->termios; + + mutex_lock(&tty->termios_mutex); + tty->termios->c_cflag &= ~CLOCAL; + tty->termios->c_cflag |= bit; + if (tty->driver->set_termios) + tty->driver->set_termios(tty, &old); + if ((tty->termios->c_cflag & CLOCAL) != bit) + ret = -EINVAL; + mutex_unlock(&tty->termios_mutex); + return ret; +} + +/** * tty_mode_ioctl - mode related ioctls * @tty: tty for the ioctl * @file: file pointer for the tty @@ -865,12 +891,7 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, case TIOCSSOFTCAR: if (get_user(arg, (unsigned int __user *) arg)) return -EFAULT; - mutex_lock(&tty->termios_mutex); - tty->termios->c_cflag = - ((tty->termios->c_cflag & ~CLOCAL) | - (arg ? CLOCAL : 0)); - mutex_unlock(&tty->termios_mutex); - return 0; + return tty_change_softcar(tty, arg); default: return -ENOIOCTLCMD; } |