Use the inline function instead of directly indexing the array.

This allows some architectures with hardware instructions
for bit reversals to eliminate the array.

Signed-off-by: Joe Perches <joe@perches.com>
---
On Sun, 2014-10-26 at 23:46 -0700, Joe Perches wrote:

On Mon, 2014-10-27 at 14:37 +0800, Wang, Yalin wrote:

quoted

this change add CONFIG_HAVE_ARCH_BITREVERSE config option,
so that we can use arm/arm64 rbit instruction to do bitrev operation
by hardware.

[]

quoted

diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h
index 7ffe03f..ef5b2bb 100644
--- a/include/linux/bitrev.h
+++ b/include/linux/bitrev.h

@@ -3,6 +3,14 @@
 
 #include <linux/types.h>
 
+#ifdef CONFIG_HAVE_ARCH_BITREVERSE
+#include <asm/bitrev.h>
+
+#define bitrev32 __arch_bitrev32
+#define bitrev16 __arch_bitrev16
+#define bitrev8 __arch_bitrev8
+
+#else
 extern u8 const byte_rev_table[256];

 drivers/net/wireless/ath/carl9170/phy.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/carl9170/phy.c b/drivers/net/wireless/ath/carl9170/phy.c
index b80b213..dca6df1 100644
--- a/drivers/net/wireless/ath/carl9170/phy.c
+++ b/drivers/net/wireless/ath/carl9170/phy.c

@@ -994,7 +994,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz,
 			refsel0 = 0;
 			refsel1 = 1;
 		}
-		chansel = byte_rev_table[chansel];
+		chansel = bitrev8(chansel);
 	} else {
 		if (freq == 2484) {
 			chansel = 10 + (freq - 2274) / 5;

@@ -1002,7 +1002,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz,
 		} else
 			chansel = 16 + (freq - 2272) / 5;
 		chansel *= 4;
-		chansel = byte_rev_table[chansel];
+		chansel = bitrev8(chansel);
 	}
 
 	d1 =	chansel;


--

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