rtc: simplified rtc sysfs attribute handling

This simplifies the RTC sysfs support by removing the class_interface that
hooks it into the rtc core.  If it's configured, then sysfs support is now
part of the RTC core, and is never a separate module.

It's another step towards being able to remove "struct class_device".

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-By: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-core.h b/drivers/rtc/rtc-core.h
index c989142..30bcd14 100644
--- a/drivers/rtc/rtc-core.h
+++ b/drivers/rtc/rtc-core.h
@@ -15,3 +15,17 @@
 #define rtc_dev_del_device(r)	do{}while(0)
 
 #endif
+
+#ifdef CONFIG_RTC_INTF_SYSFS
+
+extern void __init rtc_sysfs_init(struct class *);
+extern void rtc_sysfs_add_device(struct rtc_device *rtc);
+extern void rtc_sysfs_del_device(struct rtc_device *rtc);
+
+#else
+
+#define rtc_sysfs_init(c)	do{}while(0)
+#define rtc_sysfs_add_device(r)	do{}while(0)
+#define rtc_sysfs_del_device(r)	do{}while(0)
+
+#endif