diff options
| -rw-r--r-- | Documentation/watchdog/watchdog-kernel-api.txt | 10 | ||||
| -rw-r--r-- | drivers/watchdog/watchdog_dev.c | 20 | ||||
| -rw-r--r-- | include/linux/watchdog.h | 4 |
3 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index 429f81bf0cf..acdee39fb08 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -42,6 +42,7 @@ struct watchdog_device { const struct watchdog_info *info; const struct watchdog_ops *ops; unsigned int bootstatus; + unsigned int timeout; void *driver_data; unsigned long status; }; @@ -50,6 +51,7 @@ It contains following fields: * info: a pointer to a watchdog_info structure. This structure gives some additional information about the watchdog timer itself. (Like it's unique name) * ops: a pointer to the list of watchdog operations that the watchdog supports. +* timeout: the watchdog timer's timeout value (in seconds). * bootstatus: status of the device after booting (reported with watchdog WDIOF_* status bits). * driver_data: a pointer to the drivers private data of a watchdog device. @@ -70,6 +72,7 @@ struct watchdog_ops { /* optional operations */ int (*ping)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); + int (*set_timeout)(struct watchdog_device *, unsigned int); }; It is important that you first define the module owner of the watchdog timer @@ -107,6 +110,13 @@ they are supported. These optional routines/operations are: info structure). * status: this routine checks the status of the watchdog timer device. The status of the device is reported with watchdog WDIOF_* status flags/bits. +* set_timeout: this routine checks and changes the timeout of the watchdog + timer device. It returns 0 on success, -EINVAL for "parameter out of range" + and -EIO for "could not write value to the watchdog". On success the timeout + value of the watchdog_device will be changed to the value that was just used + to re-program the watchdog timer device. + (Note: the WDIOF_SETTIMEOUT needs to be set in the options field of the + watchdog's info structure). The status bits should (preferably) be set with the set_bit and clear_bit alike bit-operations. The status bits that are defined are: diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 9f5550e16ab..2c0289deaad 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -190,6 +190,26 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd, return -EOPNOTSUPP; watchdog_ping(wdd); return 0; + case WDIOC_SETTIMEOUT: + if ((wdd->ops->set_timeout == NULL) || + !(wdd->info->options & WDIOF_SETTIMEOUT)) + return -EOPNOTSUPP; + if (get_user(val, p)) + return -EFAULT; + err = wdd->ops->set_timeout(wdd, val); + if (err < 0) + return err; + wdd->timeout = val; + /* If the watchdog is active then we send a keepalive ping + * to make sure that the watchdog keep's running (and if + * possible that it takes the new timeout) */ + watchdog_ping(wdd); + /* Fall */ + case WDIOC_GETTIMEOUT: + /* timeout == 0 means that we don't know the timeout */ + if (wdd->timeout == 0) + return -EOPNOTSUPP; + return put_user(wdd->timeout, p); default: return -ENOTTY; } diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h index db46fe89563..9f33efe199d 100644 --- a/include/linux/watchdog.h +++ b/include/linux/watchdog.h @@ -69,6 +69,7 @@ struct watchdog_device; * @stop: The routine for stopping the watchdog device. * @ping: The routine that sends a keepalive ping to the watchdog device. * @status: The routine that shows the status of the watchdog device. + * @set_timeout:The routine for setting the watchdog devices timeout value. * * The watchdog_ops structure contains a list of low-level operations * that control a watchdog device. It also contains the module that owns @@ -83,6 +84,7 @@ struct watchdog_ops { /* optional operations */ int (*ping)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); + int (*set_timeout)(struct watchdog_device *, unsigned int); }; /** struct watchdog_device - The structure that defines a watchdog device @@ -90,6 +92,7 @@ struct watchdog_ops { * @info: Pointer to a watchdog_info structure. * @ops: Pointer to the list of watchdog operations. * @bootstatus: Status of the watchdog device at boot. + * @timeout: The watchdog devices timeout value. * @driver-data:Pointer to the drivers private data. * @status: Field that contains the devices internal status bits. * @@ -103,6 +106,7 @@ struct watchdog_device { const struct watchdog_info *info; const struct watchdog_ops *ops; unsigned int bootstatus; + unsigned int timeout; void *driver_data; unsigned long status; /* Bit numbers for status flags */ |