[WATCHDOG] orion5x_wdt: Add shutdown callback, use watchdog ping function

* Added a callback to disable the watchdog on shutdown.
* Use a separate ping function to reduce the number of register accesses
  if the watchdog is already enabled and just needs to be reloaded.
* Minor cleanup of function names.

Signed-off-by: Thomas Reitmayr <treitmayr@devbase.at>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

1 files changed, 42 insertions, 15 deletions

diff --git a/drivers/watchdog/orion5x_wdt.c b/drivers/watchdog/orion5x_wdt.c
index e81441f103dd..7529616739d2 100644
--- a/drivers/watchdog/orion5x_wdt.c
+++ b/drivers/watchdog/orion5x_wdt.c
@@ -42,7 +42,17 @@ static unsigned int wdt_tclk;
 static unsigned long wdt_status;
 static spinlock_t wdt_lock;
 
-static void wdt_enable(void)
+static void orion5x_wdt_ping(void)
+{
+        spin_lock(&wdt_lock);
+
+        /* Reload watchdog duration */
+        writel(wdt_tclk * heartbeat, WDT_VAL);
+
+        spin_unlock(&wdt_lock);
+}
+
+static void orion5x_wdt_enable(void)
 {
         u32 reg;
 
@@ -69,7 +79,7 @@ static void wdt_enable(void)
         spin_unlock(&wdt_lock);
 }
 
-static void wdt_disable(void)
+static void orion5x_wdt_disable(void)
 {
         u32 reg;
 
@@ -101,7 +111,7 @@ static int orion5x_wdt_open(struct inode *inode, struct file *file)
         if (test_and_set_bit(WDT_IN_USE, &wdt_status))
                 return -EBUSY;
         clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-        wdt_enable();
+        orion5x_wdt_enable();
         return nonseekable_open(inode, file);
 }
 
@@ -122,18 +132,28 @@ static ssize_t orion5x_wdt_write(struct file *file, const char *data,
                                         set_bit(WDT_OK_TO_CLOSE, &wdt_status);
                         }
                 }
-                wdt_enable();
+                orion5x_wdt_ping();
         }
         return len;
 }
 
-static struct watchdog_info ident = {
+static int orion5x_wdt_settimeout(int new_time)
+{
+        if ((new_time <= 0) || (new_time > wdt_max_duration))
+                return -EINVAL;
+
+        /* Set new watchdog time to be used when
+         * orion5x_wdt_enable() or orion5x_wdt_ping() is called. */
+        heartbeat = new_time;
+        return 0;
+}
+
+static const struct watchdog_info ident = {
         .options        = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT |
                           WDIOF_KEEPALIVEPING,
         .identity       = "Orion5x Watchdog",
 };
 
-
 static long orion5x_wdt_ioctl(struct file *file, unsigned int cmd,
                                 unsigned long arg)
 {
@@ -152,7 +172,7 @@ static long orion5x_wdt_ioctl(struct file *file, unsigned int cmd,
                 break;
 
         case WDIOC_KEEPALIVE:
-                wdt_enable();
+                orion5x_wdt_ping();
                 ret = 0;
                 break;
 
@@ -161,12 +181,11 @@ static long orion5x_wdt_ioctl(struct file *file, unsigned int cmd,
                 if (ret)
                         break;
 
-                if (time <= 0 || time > wdt_max_duration) {
+                if (orion5x_wdt_settimeout(time)) {
                         ret = -EINVAL;
                         break;
                 }
-                heartbeat = time;
-                wdt_enable();
+                orion5x_wdt_ping();
                 /* Fall through */
 
         case WDIOC_GETTIMEOUT:
@@ -187,7 +206,7 @@ static long orion5x_wdt_ioctl(struct file *file, unsigned int cmd,
 static int orion5x_wdt_release(struct inode *inode, struct file *file)
 {
         if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
-                wdt_disable();
+                orion5x_wdt_disable();
         else
                 printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - "
                                         "timer will not stop\n");
@@ -230,7 +249,7 @@ static int __devinit orion5x_wdt_probe(struct platform_device *pdev)
         orion5x_wdt_miscdev.parent = &pdev->dev;
 
         wdt_max_duration = WDT_MAX_CYCLE_COUNT / wdt_tclk;
-        if (heartbeat <= 0 || heartbeat > wdt_max_duration)
+        if (orion5x_wdt_settimeout(heartbeat))
                 heartbeat = wdt_max_duration;
 
         ret = misc_register(&orion5x_wdt_miscdev);
@@ -247,7 +266,7 @@ static int __devexit orion5x_wdt_remove(struct platform_device *pdev)
         int ret;
 
         if (test_bit(WDT_IN_USE, &wdt_status)) {
-                wdt_disable();
+                orion5x_wdt_disable();
                 clear_bit(WDT_IN_USE, &wdt_status);
         }
 
@@ -258,9 +277,16 @@ static int __devexit orion5x_wdt_remove(struct platform_device *pdev)
         return ret;
 }
 
+static void orion5x_wdt_shutdown(struct platform_device *pdev)
+{
+        if (test_bit(WDT_IN_USE, &wdt_status))
+                orion5x_wdt_disable();
+}
+
 static struct platform_driver orion5x_wdt_driver = {
         .probe          = orion5x_wdt_probe,
         .remove         = __devexit_p(orion5x_wdt_remove),
+        .shutdown       = orion5x_wdt_shutdown,
         .driver         = {
                 .owner  = THIS_MODULE,
                 .name   = "orion5x_wdt",
@@ -285,10 +311,11 @@ MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
 MODULE_DESCRIPTION("Orion5x Processor Watchdog");
 
 module_param(heartbeat, int, 0);
-MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds");
+MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
 
 module_param(nowayout, int, 0);
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+                                __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);