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authorSamuel Tardieu <sam@rfc1149.net>2008-03-12 14:28:03 +0100
committerWim Van Sebroeck <wim@iguana.be>2008-05-25 11:00:51 +0200
commit6fd656012bb8d5c5a4570adc2e630668b0109cb0 (patch)
treed8c480a3e929c9610d47c444f378c7caf9179046
parent[WATCHDOG] Make w83697h_wdt timeout option string similar to others (diff)
downloadlinux-6fd656012bb8d5c5a4570adc2e630668b0109cb0.tar.xz
linux-6fd656012bb8d5c5a4570adc2e630668b0109cb0.zip
[WATCHDOG] Add w83697h_wdt early_disable option
Pádraig Brady requested the possibility of not disabling the watchdog at module load time or kernel boot time if it had been previously enabled in the bios. It may help rebooting the machine if it freezes before the userland daemon kicks in. Signed-off-by: Samuel Tardieu <sam@rfc1149.net> Cc: Pádraig Brady <P@draigBrady.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
-rw-r--r--drivers/watchdog/w83697hf_wdt.c27
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/watchdog/w83697hf_wdt.c b/drivers/watchdog/w83697hf_wdt.c
index 21207021a023..528b882420b6 100644
--- a/drivers/watchdog/w83697hf_wdt.c
+++ b/drivers/watchdog/w83697hf_wdt.c
@@ -44,6 +44,7 @@
#define WATCHDOG_NAME "w83697hf/hg WDT"
#define PFX WATCHDOG_NAME ": "
#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
+#define WATCHDOG_EARLY_DISABLE 1 /* Disable until userland kicks in */
static unsigned long wdt_is_open;
static char expect_close;
@@ -62,6 +63,10 @@ static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+static int early_disable = WATCHDOG_EARLY_DISABLE;
+module_param(early_disable, int, 0);
+MODULE_PARM_DESC(early_disable, "Watchdog gets disabled at boot time (default=" __MODULE_STRING(WATCHDOG_EARLY_DISABLE) ")");
+
/*
* Kernel methods.
*/
@@ -178,6 +183,22 @@ wdt_disable(void)
spin_unlock(&io_lock);
}
+static unsigned char
+wdt_running(void)
+{
+ unsigned char t;
+
+ spin_lock(&io_lock);
+ w83697hf_select_wdt();
+
+ t = w83697hf_get_reg(0xF4); /* Read timer */
+
+ w83697hf_deselect_wdt();
+ spin_unlock(&io_lock);
+
+ return t;
+}
+
static int
wdt_set_heartbeat(int t)
{
@@ -394,7 +415,11 @@ wdt_init(void)
}
w83697hf_init();
- wdt_disable(); /* Disable watchdog until first use */
+ if (early_disable) {
+ if (wdt_running())
+ printk (KERN_WARNING PFX "Stopping previously enabled watchdog until userland kicks in\n");
+ wdt_disable();
+ }
if (wdt_set_heartbeat(timeout)) {
wdt_set_heartbeat(WATCHDOG_TIMEOUT);