From: Xenia Ragiadakou <burzalodowa@gmail.com>
Date: Sat, 15 Jun 2013 04:29:01 +0000 (+0300)
Subject: staging: rtl8192u: fix bitshift calculation in r819xU_phy.c
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=391c72a30bba9d569d5762a2f18d0dd4f3bdc5ba;p=deliverable%2Flinux.git

staging: rtl8192u: fix bitshift calculation in r819xU_phy.c

This patch uses the ffs linux built-in routine in the
computation of the bitshift to take advantage of
architecture specific instructions that implement this
computation more efficiently.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/rtl8192u/r819xU_phy.c b/drivers/staging/rtl8192u/r819xU_phy.c
index d66d88cc189e..70ab9cd0b29f 100644
--- a/drivers/staging/rtl8192u/r819xU_phy.c
+++ b/drivers/staging/rtl8192u/r819xU_phy.c
@@ -7,6 +7,8 @@
 #include "r819xU_firmware_img.h"
 
 #include "dot11d.h"
+#include <linux/bitops.h>
+
 static u32 RF_CHANNEL_TABLE_ZEBRA[] = {
 	0,
 	0x085c, //2412 1
@@ -45,11 +47,7 @@ static u32 RF_CHANNEL_TABLE_ZEBRA[] = {
 u32 rtl8192_CalculateBitShift(u32 dwBitMask)
 {
 	u32 i;
-	for (i=0; i<=31; i++)
-	{
-		if (((dwBitMask>>i)&0x1) == 1)
-			break;
-	}
+	i = ffs(dwBitMask) - 1;
 	return i;
 }
 /******************************************************************************