From: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Date: Fri, 4 Nov 2005 17:02:54 +0000 (+0900)
Subject: Define MAX_UDELAY_MS
X-Git-Tag: v3.12-rc1~40968^2~5
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a0f08209c685b4f7dccaf013da74e0e80986c477;p=kernel%2Fkernel-generic.git

Define MAX_UDELAY_MS

If HZ was 1000, mdelay(2) cause overflow on multiplication in
__udelay.  We should define MAX_UDELAY_MS properly to prevent this.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---

diff --git a/include/asm-mips/delay.h b/include/asm-mips/delay.h
index 85435a8..48d00cc 100644
--- a/include/asm-mips/delay.h
+++ b/include/asm-mips/delay.h
@@ -84,4 +84,13 @@ static inline void __udelay(unsigned long usecs, unsigned long lpj)
 
 #define udelay(usecs) __udelay((usecs),__udelay_val)
 
+/* make sure "usecs *= ..." in udelay do not overflow. */
+#if HZ >= 1000
+#define MAX_UDELAY_MS	1
+#elif HZ <= 200
+#define MAX_UDELAY_MS	5
+#else
+#define MAX_UDELAY_MS	(1000 / HZ)
+#endif
+
 #endif /* _ASM_DELAY_H */