clocksource: make CLOCKSOURCE_OF_DECLARE type safe

This ensures that a function pointer passed into CLOCKSOURCE_OF_DECLARE
takes the same arguments that we use for calling that function later.

Also fix the extraneous semicolon at end of the CLOCKSOURCE_OF_DECLARE
definition.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Rob Herring <rob.herring@calxeda.com>

1 files changed, 9 insertions, 2 deletions

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 08ed5e19d8c6..192d6d1771ee 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -332,16 +332,23 @@ extern int clocksource_mmio_init(void __iomem *, const char *,
 
 extern int clocksource_i8253_init(void);
 
+struct device_node;
+typedef void(*clocksource_of_init_fn)(struct device_node *);
 #ifdef CONFIG_CLKSRC_OF
 extern void clocksource_of_init(void);
 
 #define CLOCKSOURCE_OF_DECLARE(name, compat, fn)                        \
         static const struct of_device_id __clksrc_of_table_##name       \
                 __used __section(__clksrc_of_table)                     \
-                 = { .compatible = compat, .data = fn };
+                 = { .compatible = compat,                              \
+                     .data = (fn == (clocksource_of_init_fn)NULL) ? fn : fn }
 #else
 static inline void clocksource_of_init(void) {}
-#define CLOCKSOURCE_OF_DECLARE(name, compat, fn)
+#define CLOCKSOURCE_OF_DECLARE(name, compat, fn)                        \
+        static const struct of_device_id __clksrc_of_table_##name       \
+                __attribute__((unused))                                 \
+                 = { .compatible = compat,                              \
+                     .data = (fn == (clocksource_of_init_fn)NULL) ? fn : fn }
 #endif
 
 #endif /* _LINUX_CLOCKSOURCE_H */