dev_printk and new-style class devices

As the new-style class devices (as opposed to old-style struct
class_device) are becoming more widely used, I noticed that the
dev_printk-based functions are not working properly with these.
New-style class devices have no driver nor bus, almost by definition,
and as a result dev_driver_string(), which is used as the first
parameter of dev_printk, resolves to an empty string. This causes
entries like the following to show in my logs:

 i2c-2: adapter [SMBus stub driver] registered

Notice the unaesthetical leading whitespace. In order to fix this
problem, I suggest that we extend dev_driver_string to deal with
new-style class devices:

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 658eae5dacda..9ea12d9b48a6 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -43,7 +43,8 @@ int (*platform_notify_remove)(struct device * dev) = NULL;
 const char *dev_driver_string(struct device *dev)
 {
         return dev->driver ? dev->driver->name :
-                        (dev->bus ? dev->bus->name : "");
+                        (dev->bus ? dev->bus->name :
+                        (dev->class ? dev->class->name : ""));
 }
 EXPORT_SYMBOL(dev_driver_string);