For some watchdogs, the hardware timeout is fixed, and the watchdog driver depends on the watchdog core to handle the actual timeout. In this situation, the watchdog driver might only set the 'timeout' variable but do nothing else. This can as well be handled by the infrastructure, so make the set_timeout callback optional. If WDIOF_SETTIMEOUT is configured but the .set_timeout callback is not available, update the timeout variable in the infrastructure code. Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- v3: No changes v2: No changes --- Documentation/watchdog/watchdog-kernel-api.txt | 5 +++++ drivers/watchdog/watchdog_dev.c | 9 ++++++--- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index c127b2d457bd..dcae54033369 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -184,6 +184,11 @@ they are supported. These optional routines/operations are: (if it is larger than hw_max_timeout_ms), or to the achieved timeout value. (Note: the WDIOF_SETTIMEOUT needs to be set in the options field of the watchdog's info structure). + If the watchdog driver does not have to perform any action but setting the + watchdog_device.timeout, this callback can be omitted. + If set_timeout is not provided but, WDIOF_SETTIMEOUT is set, the watchdog + infrastructure updates the timeout value of the watchdog_device internally + to the requested value. * get_timeleft: this routines returns the time that's left before a reset. * ref: the operation that calls kref_get on the kref of a dynamically allocated watchdog_device struct. diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 631ed18d4c61..3257912c9424 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -290,9 +290,9 @@ out_status: static int watchdog_set_timeout(struct watchdog_device *wdd, unsigned int timeout) { - int err; + int err = 0; - if (!wdd->ops->set_timeout || !(wdd->info->options & WDIOF_SETTIMEOUT)) + if (!(wdd->info->options & WDIOF_SETTIMEOUT)) return -EOPNOTSUPP; if (watchdog_timeout_invalid(wdd, timeout)) @@ -305,7 +305,10 @@ static int watchdog_set_timeout(struct watchdog_device *wdd, goto out_timeout; } - err = wdd->ops->set_timeout(wdd, timeout); + if (wdd->ops->set_timeout) + err = wdd->ops->set_timeout(wdd, timeout); + else + wdd->timeout = timeout; watchdog_update_worker(wdd, true); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html