s390: remove driver_data direct access of struct device

In the near future, the driver core is going to not allow direct access
to the driver_data pointer in struct device.  Instead, the functions
dev_get_drvdata() and dev_set_drvdata() should be used.  These functions
have been around since the beginning, so are backwards compatible with
all older kernel versions.

Thanks to Sebastian Ott <sebott@linux.vnet.ibm.com> for fixing a few
typos in my original version of this patch.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: linux390@de.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/s390/char/vmlogrdr.c b/drivers/s390/char/vmlogrdr.c
index d8a2289..ee1b418 100644
--- a/drivers/s390/char/vmlogrdr.c
+++ b/drivers/s390/char/vmlogrdr.c
@@ -504,7 +504,7 @@
 					struct device_attribute *attr,
 					const char * buf, size_t count)
 {
-	struct vmlogrdr_priv_t *priv = dev->driver_data;
+	struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
 	ssize_t ret = count;
 
 	switch (buf[0]) {
@@ -525,7 +525,7 @@
 				       struct device_attribute *attr,
 				       char *buf)
 {
-	struct vmlogrdr_priv_t *priv = dev->driver_data;
+	struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
 	return sprintf(buf, "%u\n", priv->autopurge);
 }
 
@@ -541,7 +541,7 @@
 
 	char cp_command[80];
 	char cp_response[80];
-	struct vmlogrdr_priv_t *priv = dev->driver_data;
+	struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
 
 	if (buf[0] != '1')
 		return -EINVAL;
@@ -578,7 +578,7 @@
 					    struct device_attribute *attr,
 					    const char *buf, size_t count)
 {
-	struct vmlogrdr_priv_t *priv = dev->driver_data;
+	struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
 	ssize_t ret = count;
 
 	switch (buf[0]) {
@@ -599,7 +599,7 @@
 					   struct device_attribute *attr,
 					   char *buf)
 {
-	struct vmlogrdr_priv_t *priv = dev->driver_data;
+	struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
 	return sprintf(buf, "%u\n", priv->autorecording);
 }
 
@@ -612,7 +612,7 @@
 					struct device_attribute *attr,
 					const char * buf, size_t count)
 {
-	struct vmlogrdr_priv_t *priv = dev->driver_data;
+	struct vmlogrdr_priv_t *priv = dev_get_drvdata(dev);
 	ssize_t ret;
 
 	switch (buf[0]) {