static int xwdt_release(struct inode *inode, struct file *file)
{
if (expect_close == 42) {
xwdt_stop();
} else {
pr_crit("Unexpected close, not stopping watchdog!\n");
xwdt_keepalive();
}
clear_bit(0, &driver_open);
expect_close = 0;
return 0;
}
/*
* xwdt_ioctl:
* @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 xwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
int status;
union {
struct watchdog_info __user *ident;
int __user *i;
} uarg;
uarg.i = (int __user *)arg;
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(uarg.ident, &ident,
sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETBOOTSTATUS:
return put_user(xdev.boot_status, uarg.i);
case WDIOC_GETSTATUS:
xwdt_get_status(&status);
return put_user(status, uarg.i);
case WDIOC_KEEPALIVE:
xwdt_keepalive();
return 0;
case WDIOC_SETTIMEOUT:
printk(KERN_INFO "This feature is not implemented yet!\n");
case WDIOC_GETTIMEOUT:
if (no_timeout)
return -ENOTTY;
else
return put_user(timeout, uarg.i);
default:
return -ENOTTY;
}
}
/*
* xwdt_write:
* @file: file handle to the watchdog
* @buf: buffer to write (unused as data does not matter here
* @count: count of bytes
* @ppos: pointer to the position to write. No seeks allowed
*
* A write to a watchdog device is defined as a keepalive signal. Any
* write of data will do, as we don't define content meaning.
*/
static ssize_t xwdt_write(struct file *file, const char __user *buf,
size_t len, loff_t *ppos)
{
if (len) {
if (!xdev.nowayout) {
size_t i;
/* In case it was set long ago */
expect_close = 0;
for (i = 0; i != len; i++) {
char c;
if (get_user(c, buf + i))
return -EFAULT;
if (c == 'V')
expect_close = 42;
}
}
xwdt_keepalive();
}
return len;
}