bitops: Provide generic sign_extend32 function

This patch moves code out from wireless drivers where two different
functions are defined in three code locations for the same purpose and
provides a common function to sign extend a 32-bit value.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

5 files changed, 17 insertions, 29 deletions

diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c
index 219367884e64..6b43f535ff53 100644
--- a/drivers/net/wireless/ath/ath5k/phy.c
+++ b/drivers/net/wireless/ath/ath5k/phy.c
@@ -1102,18 +1102,12 @@ int ath5k_hw_channel(struct ath5k_hw *ah, struct ieee80211_channel *channel)
   PHY calibration
 \*****************/
 
-static int sign_extend(int val, const int nbits)
-{
-	int order = BIT(nbits-1);
-	return (val ^ order) - order;
-}
-
 static s32 ath5k_hw_read_measured_noise_floor(struct ath5k_hw *ah)
 {
 	s32 val;
 
 	val = ath5k_hw_reg_read(ah, AR5K_PHY_NF);
-	return sign_extend(AR5K_REG_MS(val, AR5K_PHY_NF_MINCCA_PWR), 9);
+	return sign_extend32(AR5K_REG_MS(val, AR5K_PHY_NF_MINCCA_PWR), 8);
 }
 
 void ath5k_hw_init_nfcal_hist(struct ath5k_hw *ah)
diff --git a/drivers/net/wireless/ath/ath9k/ar5008_phy.c b/drivers/net/wireless/ath/ath9k/ar5008_phy.c
index 777a602176f2..c83a22cfbe1e 100644
--- a/drivers/net/wireless/ath/ath9k/ar5008_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar5008_phy.c
@@ -1490,25 +1490,25 @@ static void ar5008_hw_do_getnf(struct ath_hw *ah,
 	int16_t nf;
 
 	nf = MS(REG_READ(ah, AR_PHY_CCA), AR_PHY_MINCCA_PWR);
-	nfarray[0] = sign_extend(nf, 9);
+	nfarray[0] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CH1_CCA), AR_PHY_CH1_MINCCA_PWR);
-	nfarray[1] = sign_extend(nf, 9);
+	nfarray[1] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CH2_CCA), AR_PHY_CH2_MINCCA_PWR);
-	nfarray[2] = sign_extend(nf, 9);
+	nfarray[2] = sign_extend32(nf, 8);
 
 	if (!IS_CHAN_HT40(ah->curchan))
 		return;
 
 	nf = MS(REG_READ(ah, AR_PHY_EXT_CCA), AR_PHY_EXT_MINCCA_PWR);
-	nfarray[3] = sign_extend(nf, 9);
+	nfarray[3] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CH1_EXT_CCA), AR_PHY_CH1_EXT_MINCCA_PWR);
-	nfarray[4] = sign_extend(nf, 9);
+	nfarray[4] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CH2_EXT_CCA), AR_PHY_CH2_EXT_MINCCA_PWR);
-	nfarray[5] = sign_extend(nf, 9);
+	nfarray[5] = sign_extend32(nf, 8);
 }
 
 /*
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_phy.c b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
index c00cdc67b55b..3fb97fdc1240 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
@@ -473,21 +473,21 @@ static void ar9002_hw_do_getnf(struct ath_hw *ah,
 	int16_t nf;
 
 	nf = MS(REG_READ(ah, AR_PHY_CCA), AR9280_PHY_MINCCA_PWR);
-	nfarray[0] = sign_extend(nf, 9);
+	nfarray[0] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_EXT_CCA), AR9280_PHY_EXT_MINCCA_PWR);
 	if (IS_CHAN_HT40(ah->curchan))
-		nfarray[3] = sign_extend(nf, 9);
+		nfarray[3] = sign_extend32(nf, 8);
 
 	if (AR_SREV_9285(ah) || AR_SREV_9271(ah))
 		return;
 
 	nf = MS(REG_READ(ah, AR_PHY_CH1_CCA), AR9280_PHY_CH1_MINCCA_PWR);
-	nfarray[1] = sign_extend(nf, 9);
+	nfarray[1] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CH1_EXT_CCA), AR9280_PHY_CH1_EXT_MINCCA_PWR);
 	if (IS_CHAN_HT40(ah->curchan))
-		nfarray[4] = sign_extend(nf, 9);
+		nfarray[4] = sign_extend32(nf, 8);
 }
 
 static void ar9002_hw_set_nf_limits(struct ath_hw *ah)
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index 06a9c4cd2f44..44c5454b2ad8 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -1023,25 +1023,25 @@ static void ar9003_hw_do_getnf(struct ath_hw *ah,
 	int16_t nf;
 
 	nf = MS(REG_READ(ah, AR_PHY_CCA_0), AR_PHY_MINCCA_PWR);
-	nfarray[0] = sign_extend(nf, 9);
+	nfarray[0] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CCA_1), AR_PHY_CH1_MINCCA_PWR);
-	nfarray[1] = sign_extend(nf, 9);
+	nfarray[1] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_CCA_2), AR_PHY_CH2_MINCCA_PWR);
-	nfarray[2] = sign_extend(nf, 9);
+	nfarray[2] = sign_extend32(nf, 8);
 
 	if (!IS_CHAN_HT40(ah->curchan))
 		return;
 
 	nf = MS(REG_READ(ah, AR_PHY_EXT_CCA), AR_PHY_EXT_MINCCA_PWR);
-	nfarray[3] = sign_extend(nf, 9);
+	nfarray[3] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_EXT_CCA_1), AR_PHY_CH1_EXT_MINCCA_PWR);
-	nfarray[4] = sign_extend(nf, 9);
+	nfarray[4] = sign_extend32(nf, 8);
 
 	nf = MS(REG_READ(ah, AR_PHY_EXT_CCA_2), AR_PHY_CH2_EXT_MINCCA_PWR);
-	nfarray[5] = sign_extend(nf, 9);
+	nfarray[5] = sign_extend32(nf, 8);
 }
 
 static void ar9003_hw_set_nf_limits(struct ath_hw *ah)
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index e5b72262fd96..f821a28bcda3 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -825,12 +825,6 @@ static inline struct ath_hw_ops *ath9k_hw_ops(struct ath_hw *ah)
 	return &ah->ops;
 }
 
-static inline int sign_extend(int val, const int nbits)
-{
-	int order = BIT(nbits-1);
-	return (val ^ order) - order;
-}
-
 /* Initialization, Detach, Reset */
 const char *ath9k_hw_probe(u16 vendorid, u16 devid);
 void ath9k_hw_deinit(struct ath_hw *ah);