[WATCHDOG] Add w83697h_wdt early_disable option

[cascardo/linux.git] / drivers / watchdog / w83697hf_wdt.c

diff --git a/drivers/watchdog/w83697hf_wdt.c b/drivers/watchdog/w83697hf_wdt.c
index 2120702..528b882 100644 (file)
--- 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);