Instead of returning success when a driver does not support break signalling, return an error to let user space know and to avoid waiting when break is not supported. Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> --- drivers/usb/serial/usb-serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index 470634444af7..7b4805c1004d 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -541,7 +541,7 @@ static int serial_break(struct tty_struct *tty, int break_state) if (port->serial->type->break_ctl) return port->serial->type->break_ctl(tty, break_state); - return 0; + return -ENOTTY; } static int serial_proc_show(struct seq_file *m, void *v) -- 2.39.3