diff options
| -rw-r--r-- | Documentation/watchdog/watchdog-kernel-api.txt | 6 | ||||
| -rw-r--r-- | drivers/watchdog/watchdog_dev.c | 32 | ||||
| -rw-r--r-- | include/linux/watchdog.h | 4 |
3 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt index 3db67e74b80e..2bdc6dc6e04c 100644 --- a/Documentation/watchdog/watchdog-kernel-api.txt +++ b/Documentation/watchdog/watchdog-kernel-api.txt @@ -41,6 +41,7 @@ The watchdog device structure looks like this: struct watchdog_device { const struct watchdog_info *info; const struct watchdog_ops *ops; + unsigned int bootstatus; void *driver_data; unsigned long status; }; @@ -49,6 +50,8 @@ 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. +* 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. This data should only be accessed via the watchdog_set_drvadata and watchdog_get_drvdata routines. @@ -65,6 +68,7 @@ struct watchdog_ops { int (*stop)(struct watchdog_device *); /* optional operations */ int (*ping)(struct watchdog_device *); + unsigned int (*status)(struct watchdog_device *); }; It is important that you first define the module owner of the watchdog timer @@ -97,6 +101,8 @@ they are supported. These optional routines/operations are: the watchdog timer driver core does: to send a keepalive ping to the watchdog timer hardware it will either use the ping operation (when available) or the start operation (when the ping operation is not available). +* status: this routine checks the status of the watchdog timer device. The + status of the device is reported with watchdog WDIOF_* status flags/bits. 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 366f49ce69b8..00a611293065 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -95,6 +95,37 @@ static ssize_t watchdog_write(struct file *file, const char __user *data, } /* + * watchdog_ioctl: handle the different ioctl's for the watchdog device. + * @file: file handle to the device + * @cmd: watchdog command + * @arg: argument pointer + * + * The watchdog API defines a common set of functions for all watchdogs + * according to their available features. + */ + +static long watchdog_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + unsigned int val; + + switch (cmd) { + case WDIOC_GETSUPPORT: + return copy_to_user(argp, wdd->info, + sizeof(struct watchdog_info)) ? -EFAULT : 0; + case WDIOC_GETSTATUS: + val = wdd->ops->status ? wdd->ops->status(wdd) : 0; + return put_user(val, p); + case WDIOC_GETBOOTSTATUS: + return put_user(wdd->bootstatus, p); + default: + return -ENOTTY; + } +} + +/* * watchdog_open: open the /dev/watchdog device. * @inode: inode of device * @file: file handle to device @@ -163,6 +194,7 @@ static int watchdog_release(struct inode *inode, struct file *file) static const struct file_operations watchdog_fops = { .owner = THIS_MODULE, .write = watchdog_write, + .unlocked_ioctl = watchdog_ioctl, .open = watchdog_open, .release = watchdog_release, }; diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h index 5ab31bfd2906..29ff80807dd4 100644 --- a/include/linux/watchdog.h +++ b/include/linux/watchdog.h @@ -68,6 +68,7 @@ struct watchdog_device; * @start: The routine for starting the 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. * * The watchdog_ops structure contains a list of low-level operations * that control a watchdog device. It also contains the module that owns @@ -81,12 +82,14 @@ struct watchdog_ops { int (*stop)(struct watchdog_device *); /* optional operations */ int (*ping)(struct watchdog_device *); + unsigned int (*status)(struct watchdog_device *); }; /** struct watchdog_device - The structure that defines a watchdog device * * @info: Pointer to a watchdog_info structure. * @ops: Pointer to the list of watchdog operations. + * @bootstatus: Status of the watchdog device at boot. * @driver-data:Pointer to the drivers private data. * @status: Field that contains the devices internal status bits. * @@ -99,6 +102,7 @@ struct watchdog_ops { struct watchdog_device { const struct watchdog_info *info; const struct watchdog_ops *ops; + unsigned int bootstatus; void *driver_data; unsigned long status; /* Bit numbers for status flags */ |