2004-10-21 21:01:31

by Paul Fulghum

[permalink] [raw]
Subject: [PATCH 2.4] serial send_break duration fix

Fix tty_io.c send_break() to assert break for proper duration.
If driver break_ctl() changes task state, then break may end
prematurely. USB serial driver break_ctl() sends a URB,
changing task state to TASK_RUNNING.

Signed-off-by: Paul Fulghum <[email protected]>

--
Paul Fulghum
[email protected]

--- linux-2.4.28-pre4/drivers/char/tty_io.c 2004-04-14 08:05:29.000000000 -0500
+++ b/drivers/char/tty_io.c 2004-10-21 15:55:40.516247240 -0500
@@ -1684,11 +1684,11 @@ static int tiocsetd(struct tty_struct *t

static int send_break(struct tty_struct *tty, int duration)
{
- set_current_state(TASK_INTERRUPTIBLE);
-
tty->driver.break_ctl(tty, -1);
- if (!signal_pending(current))
+ if (!signal_pending(current)) {
+ set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(duration);
+ }
tty->driver.break_ctl(tty, 0);
if (signal_pending(current))
return -EINTR;