misc: c2port: use kobj_to_dev()

Use kobj_to_dev() instead of open-coding it.

Signed-off-by: Geliang Tang <[e-mail]>
Reviewed-by: Viresh Kumar <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/misc/c2port/core.c

···
 				struct bin_attribute *attr,
 				char *buffer, loff_t offset, size_t count)
 {
-	struct c2port_device *c2dev =
-			dev_get_drvdata(container_of(kobj,
-						struct device, kobj));
+	struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
 	ssize_t ret;
 
 	/* Check the device and flash access status */
···
 				struct bin_attribute *attr,
 				char *buffer, loff_t offset, size_t count)
 {
-	struct c2port_device *c2dev =
-			dev_get_drvdata(container_of(kobj,
-						struct device, kobj));
+	struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
 	int ret;
 
 	/* Check the device access status */