From 3b24e9f8c07fc09174e4f2fe4d0f716595ae2146 Mon Sep 17 00:00:00 2001 From: Sujith Manoharan Date: Tue, 14 Jan 2014 13:41:17 +0530 Subject: [PATCH] ath9k: Fix possible overflow condition Prevent a possible overflow condition which results in occasional bad IQ coefficients and EVM numbers. Signed-off-by: Sujith Manoharan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/ar9003_calib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath9k/ar9003_calib.c b/drivers/net/wireless/ath/ath9k/ar9003_calib.c index 4eb35aa..a352128 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_calib.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_calib.c @@ -565,7 +565,7 @@ static bool ar9003_hw_solve_iq_cal(struct ath_hw *ah, const s32 result_shift = 1 << 15; struct ath_common *common = ath9k_hw_common(ah); - f2 = (f1 * f1 + f3 * f3) / result_shift; + f2 = ((f1 >> 3) * (f1 >> 3) + (f3 >> 3) * (f3 >> 3)) >> 9; if (!f2) { ath_dbg(common, CALIBRATE, "Divide by 0\n"); -- 2.7.4