diff options
author | Mike Frysinger <vapier@gentoo.org> | 2010-02-15 19:32:25 -0500 |
---|---|---|
committer | Wim Van Sebroeck <wim@iguana.be> | 2010-02-21 19:16:30 +0000 |
commit | 3dae93ec3ee1fceec69f40ef9b97892ce62ba7a5 (patch) | |
tree | 71901f55ab30c1108043d80b93c462c15c2746a8 | |
parent | aea187c46f7d03ce985e55eb1398d0776a15b928 (diff) |
[WATCHDOG] bfin: fix max timeout calculation
Relying on overflow/wrap around isn't exact because if you wrap far
enough, you get back to "valid" values.
Reported-by: Thorsten Pohlmann <pohlmann@tetronik.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: stable <stable@kernel.org>
-rw-r--r-- | drivers/watchdog/bfin_wdt.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/watchdog/bfin_wdt.c b/drivers/watchdog/bfin_wdt.c index c7b3f9df2317..2159e668751c 100644 --- a/drivers/watchdog/bfin_wdt.c +++ b/drivers/watchdog/bfin_wdt.c @@ -1,9 +1,8 @@ /* * Blackfin On-Chip Watchdog Driver - * Supports BF53[123]/BF53[467]/BF54[2489]/BF561 * * Originally based on softdog.c - * Copyright 2006-2007 Analog Devices Inc. + * Copyright 2006-2010 Analog Devices Inc. * Copyright 2006-2007 Michele d'Amico * Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk> * @@ -137,13 +136,15 @@ static int bfin_wdt_running(void) */ static int bfin_wdt_set_timeout(unsigned long t) { - u32 cnt; + u32 cnt, max_t, sclk; unsigned long flags; - stampit(); + sclk = get_sclk(); + max_t = -1 / sclk; + cnt = t * sclk; + stamp("maxtimeout=%us newtimeout=%lus (cnt=%#x)", max_t, t, cnt); - cnt = t * get_sclk(); - if (cnt < get_sclk()) { + if (t > max_t) { printk(KERN_WARNING PFX "timeout value is too large\n"); return -EINVAL; } |