watchdog: WatchDog Timer Driver Core - Add WDIOC_SETOPTIONS ioctl
This part add's the WDIOC_SETOPTIONS ioctl functionality
to the WatchDog Timer Driver Core framework.
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 2fb4cec..9f5550e 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -54,14 +54,64 @@
* If the watchdog has no own ping operation then it needs to be
* restarted via the start operation. This wrapper function does
* exactly that.
+ * We only ping when the watchdog device is running.
*/
static int watchdog_ping(struct watchdog_device *wddev)
{
- if (wddev->ops->ping)
- return wddev->ops->ping(wddev); /* ping the watchdog */
- else
- return wddev->ops->start(wddev); /* restart the watchdog */
+ if (test_bit(WDOG_ACTIVE, &wdd->status)) {
+ if (wddev->ops->ping)
+ return wddev->ops->ping(wddev); /* ping the watchdog */
+ else
+ return wddev->ops->start(wddev); /* restart watchdog */
+ }
+ return 0;
+}
+
+/*
+ * watchdog_start: wrapper to start the watchdog.
+ * @wddev: the watchdog device to start
+ *
+ * Start the watchdog if it is not active and mark it active.
+ * This function returns zero on success or a negative errno code for
+ * failure.
+ */
+
+static int watchdog_start(struct watchdog_device *wddev)
+{
+ int err;
+
+ if (!test_bit(WDOG_ACTIVE, &wdd->status)) {
+ err = wddev->ops->start(wddev);
+ if (err < 0)
+ return err;
+
+ set_bit(WDOG_ACTIVE, &wdd->status);
+ }
+ return 0;
+}
+
+/*
+ * watchdog_stop: wrapper to stop the watchdog.
+ * @wddev: the watchdog device to stop
+ *
+ * Stop the watchdog if it is still active and unmark it active.
+ * This function returns zero on success or a negative errno code for
+ * failure.
+ */
+
+static int watchdog_stop(struct watchdog_device *wddev)
+{
+ int err;
+
+ if (test_bit(WDOG_ACTIVE, &wdd->status)) {
+ err = wddev->ops->stop(wddev);
+ if (err < 0)
+ return err;
+
+ clear_bit(WDOG_ACTIVE, &wdd->status);
+ }
+ return 0;
}
/*
@@ -110,6 +160,7 @@
void __user *argp = (void __user *)arg;
int __user *p = argp;
unsigned int val;
+ int err;
switch (cmd) {
case WDIOC_GETSUPPORT:
@@ -120,6 +171,20 @@
return put_user(val, p);
case WDIOC_GETBOOTSTATUS:
return put_user(wdd->bootstatus, p);
+ case WDIOC_SETOPTIONS:
+ if (get_user(val, p))
+ return -EFAULT;
+ if (val & WDIOS_DISABLECARD) {
+ err = watchdog_stop(wdd);
+ if (err < 0)
+ return err;
+ }
+ if (val & WDIOS_ENABLECARD) {
+ err = watchdog_start(wdd);
+ if (err < 0)
+ return err;
+ }
+ return 0;
case WDIOC_KEEPALIVE:
if (!(wdd->info->options & WDIOF_KEEPALIVEPING))
return -EOPNOTSUPP;
@@ -155,7 +220,7 @@
if (!try_module_get(wdd->ops->owner))
goto out;
- err = wdd->ops->start(wdd);
+ err = watchdog_start(wdd);
if (err < 0)
goto out_mod;
@@ -181,8 +246,8 @@
{
int err;
- err = wdd->ops->stop(wdd);
- if (err != 0) {
+ err = watchdog_stop(wdd);
+ if (err < 0) {
pr_crit("%s: watchdog did not stop!\n", wdd->info->identity);
watchdog_ping(wdd);
}