[PATCH] generic-time: add macro to simplify/hide mask constants

Add a CLOCKSOURCE_MASK macro to simplify initializing the mask for a struct
clocksource, and use it to replace literal mask constants in the various
clocksource drivers.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 5f4a7f7..4bc9428 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -65,6 +65,8 @@
 	u64 interval_snsecs;
 };
 
+/* simplify initialization of mask field */
+#define CLOCKSOURCE_MASK(bits) (cycle_t)(bits<64 ? ((1ULL<<bits)-1) : -1)
 
 /**
  * clocksource_khz2mult - calculates mult from khz and shift