watchdog: ts72xx_wdt: cleanup return codes in ioctl

There seems to be some confusion here which functions return positive
numbers and which return negative error codes.

copy_to_user() returns the number of bytes remaining to be copied but we
want to return -EFAULT.

The rest is just clean up.  get_user() actually returns zero on success
and -EFAULT on error so we can preserve the error code.  The
timeout_to_regval() function returns -EINVAL on failure, but we can
propogate that back instead of hardcoding -EINVAL ourselves.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
--
This commit is contained in:
Dan Carpenter 2013-08-23 12:38:32 +03:00 committed by Wim Van Sebroeck
parent cfff96e69f
commit a20a99fbb8
1 changed files with 16 additions and 20 deletions

View File

@ -305,7 +305,8 @@ static long ts72xx_wdt_ioctl(struct file *file, unsigned int cmd,
switch (cmd) {
case WDIOC_GETSUPPORT:
error = copy_to_user(argp, &winfo, sizeof(winfo));
if (copy_to_user(argp, &winfo, sizeof(winfo)))
error = -EFAULT;
break;
case WDIOC_GETSTATUS:
@ -320,10 +321,9 @@ static long ts72xx_wdt_ioctl(struct file *file, unsigned int cmd,
case WDIOC_SETOPTIONS: {
int options;
if (get_user(options, p)) {
error = -EFAULT;
error = get_user(options, p);
if (error)
break;
}
error = -EINVAL;
@ -341,30 +341,26 @@ static long ts72xx_wdt_ioctl(struct file *file, unsigned int cmd,
case WDIOC_SETTIMEOUT: {
int new_timeout;
int regval;
if (get_user(new_timeout, p)) {
error = -EFAULT;
} else {
int regval;
regval = timeout_to_regval(new_timeout);
if (regval < 0) {
error = -EINVAL;
} else {
ts72xx_wdt_stop(wdt);
wdt->regval = regval;
ts72xx_wdt_start(wdt);
}
}
error = get_user(new_timeout, p);
if (error)
break;
regval = timeout_to_regval(new_timeout);
if (regval < 0) {
error = regval;
break;
}
ts72xx_wdt_stop(wdt);
wdt->regval = regval;
ts72xx_wdt_start(wdt);
/*FALLTHROUGH*/
}
case WDIOC_GETTIMEOUT:
if (put_user(regval_to_timeout(wdt->regval), p))
error = -EFAULT;
error = put_user(regval_to_timeout(wdt->regval), p);
break;
default: