From: Jiri Slaby <jirislaby@gmail.com>
Date: Thu, 16 Oct 2008 05:04:17 +0000 (-0700)
Subject: Char: ds1286, eliminate busy waiting
X-Git-Tag: v2.6.28-rc1~352
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d05abab9a47d3245664eee413769af2e1e4b1faf;p=pandora-kernel.git

Char: ds1286, eliminate busy waiting

ds1286_get_time(); is not called from atomic context, sleep for 20 ms is
better choice than a (home-made) busy waiting for such a situation.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/drivers/char/ds1286.c b/drivers/char/ds1286.c
index fb584938c9c3..5329d482b582 100644
--- a/drivers/char/ds1286.c
+++ b/drivers/char/ds1286.c
@@ -443,7 +443,6 @@ static void ds1286_get_time(struct rtc_time *rtc_tm)
 {
 	unsigned char save_control;
 	unsigned long flags;
-	unsigned long uip_watchdog = jiffies;
 
 	/*
 	 * read RTC once any update in progress is done. The update
@@ -456,8 +455,7 @@ static void ds1286_get_time(struct rtc_time *rtc_tm)
 	 */
 
 	if (ds1286_is_updating() != 0)
-		while (time_before(jiffies, uip_watchdog + 2*HZ/100))
-			barrier();
+		msleep(20);
 
 	/*
 	 * Only the values that we read from the RTC are set. We leave