On Fri, Aug 27, 2010 at 03:16:51AM -0700, Andreas Herrmann wrote: > From: Andreas Herrmann <andreas.herrmann3@xxxxxxx> > > Provide a common function to sign extend a value. > > Signed-off-by: Andreas Herrmann <andreas.herrmann3@xxxxxxx> > --- > drivers/net/wireless/ath/ath5k/phy.c | 6 ------ > drivers/net/wireless/ath/ath9k/hw.h | 6 ------ > drivers/net/wireless/iwlwifi/iwl-4965.c | 16 ---------------- > include/linux/bitops.h | 11 +++++++++++ > 4 files changed, 11 insertions(+), 28 deletions(-) > > Recently I needed to sign extend some register values for further > computation. I also stumbled over two functions in wireless code > which do the same (in different ways). > > Thus I wonder whether a generic function should be provided for this. > > Below patch (against tip/master) provides the iwl-4965-variant of that > function in bitops.h I am not sure whether that's the right place to > add this function. What do you think? Or is it a dumb idea anyway? Think its reasonable. Adding linux-wireless. Luis > > > Thanks, > Andreas > > diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c > index 6284c38..9e6f551 100644 > --- a/drivers/net/wireless/ath/ath5k/phy.c > +++ b/drivers/net/wireless/ath/ath5k/phy.c > @@ -1101,12 +1101,6 @@ 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; > diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h > index 399f7c1..5dad02f 100644 > --- a/drivers/net/wireless/ath/ath9k/hw.h > +++ b/drivers/net/wireless/ath/ath9k/hw.h > @@ -858,12 +858,6 @@ 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); > diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.c b/drivers/net/wireless/iwlwifi/iwl-4965.c > index d92b729..9a53dee 100644 > --- a/drivers/net/wireless/iwlwifi/iwl-4965.c > +++ b/drivers/net/wireless/iwlwifi/iwl-4965.c > @@ -1551,22 +1551,6 @@ static void iwl4965_txq_update_byte_cnt_tbl(struct iwl_priv *priv, > } > > /** > - * sign_extend - Sign extend a value using specified bit as sign-bit > - * > - * Example: sign_extend(9, 3) would return -7 as bit3 of 1001b is 1 > - * and bit0..2 is 001b which when sign extended to 1111111111111001b is -7. > - * > - * @param oper value to sign extend > - * @param index 0 based bit index (0<=index<32) to sign bit > - */ > -static s32 sign_extend(u32 oper, int index) > -{ > - u8 shift = 31 - index; > - > - return (s32)(oper << shift) >> shift; > -} > - > -/** > * iwl4965_hw_get_temperature - return the calibrated temperature (in Kelvin) > * @statistics: Provides the temperature reading from the uCode > * > diff --git a/include/linux/bitops.h b/include/linux/bitops.h > index fc68053..618f69e 100644 > --- a/include/linux/bitops.h > +++ b/include/linux/bitops.h > @@ -109,6 +109,17 @@ static inline __u8 ror8(__u8 word, unsigned int shift) > return (word >> shift) | (word << (8 - shift)); > } > > +/** > + * sign_extend - Sign extend a value using specified bit as sign-bit > + * @value: value to sign extend > + * @index: 0 based bit index (0<=index<32) to sign bit > + */ > +static inline __s32 sign_extend(__u32 value, int index) > +{ > + __u8 shift = 31 - index; > + return (__s32)(value << shift) >> shift; > +} > + > static inline unsigned fls_long(unsigned long l) > { > if (sizeof(l) == 4) > -- > 1.6.4.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html