drivers/char/rtc.c: use time_before, time_before_eq, etc

Author: Julia Lawall <julia@diku.dk>

The functions time_before, time_before_eq, time_after, and time_after_eq
are more robust for comparing jiffies against other values.

A simplified version of the semantic patch making this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// 
@ change_compare_np @
expression E;
@@

(
- jiffies <= E
+ time_before_eq(jiffies,E)
|
- jiffies >= E
+ time_after_eq(jiffies,E)
|
- jiffies < E
+ time_before(jiffies,E)
|
- jiffies > E
+ time_after(jiffies,E)
)

@ include depends on change_compare_np @
@@

#include 

@ no_include depends on !include && change_compare_np @
@@

  #include 
+ #include 
// 

Signed-off-by: Julia Lawall 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Alessandro Zummo 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
---
 drivers/char/rtc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
 
diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c
index 5c3142b..e2ec2ee 100644
--- a/drivers/char/rtc.c
+++ b/drivers/char/rtc.c
@@ -88,6 +88,7 @@
 
 #ifdef CONFIG_SPARC32
 #include <linux/pci.h>
+#include <linux/jiffies.h>
 #include <asm/ebus.h>
 
 static unsigned long rtc_port;
@@ -1316,7 +1317,8 @@ void rtc_get_rtc_time(struct rtc_time *rtc_tm)
 	 * Once the read clears, read the RTC time (again via ioctl). Easy.
 	 */
 
-	while (rtc_is_updating() != 0 && jiffies - uip_watchdog < 2*HZ/100)
+	while (rtc_is_updating() != 0 &&
+	       time_before(jiffies, uip_watchdog + 2*HZ/100))
 		cpu_relax();
 
 	/*
BtrLinux
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