[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/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index 066dc77..7ad3be8 100644
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -32,7 +32,7 @@
  */
 u32 pmtmr_ioport __read_mostly;
 
-#define ACPI_PM_MASK 0xFFFFFF /* limit it to 24 bits */
+#define ACPI_PM_MASK CLOCKSOURCE_MASK(24) /* limit it to 24 bits */
 
 static inline u32 read_pmtmr(void)
 {