The bitrate value for airtime calculation is specified for full rates. We need to divide it for 5 and 10MHz channels to get correct result. Signed-off-by: Wojciech Dubowik <Wojciech.Dubowik@xxxxxxxxxxx> --- drivers/net/wireless/ath/ath9k/hw.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index cd0f023..3017078 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -184,7 +184,8 @@ u16 ath9k_hw_computetxtime(struct ath_hw *ah, break; case WLAN_RC_PHY_OFDM: if (ah->curchan && IS_CHAN_QUARTER_RATE(ah->curchan)) { - bitsPerSymbol = (kbps * OFDM_SYMBOL_TIME_QUARTER) / 1000; + bitsPerSymbol = + ((kbps >> 2) * OFDM_SYMBOL_TIME_QUARTER) / 1000; numBits = OFDM_PLCP_BITS + (frameLen << 3); numSymbols = DIV_ROUND_UP(numBits, bitsPerSymbol); txTime = OFDM_SIFS_TIME_QUARTER @@ -192,7 +193,8 @@ u16 ath9k_hw_computetxtime(struct ath_hw *ah, + (numSymbols * OFDM_SYMBOL_TIME_QUARTER); } else if (ah->curchan && IS_CHAN_HALF_RATE(ah->curchan)) { - bitsPerSymbol = (kbps * OFDM_SYMBOL_TIME_HALF) / 1000; + bitsPerSymbol = + ((kbps >> 1) * OFDM_SYMBOL_TIME_HALF) / 1000; numBits = OFDM_PLCP_BITS + (frameLen << 3); numSymbols = DIV_ROUND_UP(numBits, bitsPerSymbol); txTime = OFDM_SIFS_TIME_HALF + -- 2.7.4