From e948b99d6f38b726ad1c8f99a2672b792756b549 Mon Sep 17 00:00:00 2001 From: Rajkumar Manoharan Date: Tue, 6 Sep 2011 21:59:51 +0530 Subject: [PATCH] ath9k_hw: Fix magnitude/phase average in TxIQ Calibration The commit "ath9k_hw: Fix Tx IQ Calibration hang issue in AR9003 chips" did not consider more than one potential sample while calculating magnitude/phase average if more than one sample has the same value which could affect post-processing of outlier detection that causes an undesirable Tx IQ correction value will be assigned to tx gain settings where outlier happens. Cc: Kai Shi Reported-by: Paul Stewart Signed-off-by: Rajkumar Manoharan Signed-off-by: Paul Stewart Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/ar9003_calib.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ar9003_calib.c b/drivers/net/wireless/ath/ath9k/ar9003_calib.c index fa35a0235f44..3319a676c0fb 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_calib.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_calib.c @@ -615,11 +615,10 @@ static void ar9003_hw_detect_outlier(int *mp_coeff, int nmeasurement, { int mp_max = -64, max_idx = 0; int mp_min = 63, min_idx = 0; - int mp_avg = 0, i, outlier_idx = 0; + int mp_avg = 0, i, outlier_idx = 0, mp_count = 0; /* find min/max mismatch across all calibrated gains */ for (i = 0; i < nmeasurement; i++) { - mp_avg += mp_coeff[i]; if (mp_coeff[i] > mp_max) { mp_max = mp_coeff[i]; max_idx = i; @@ -632,10 +631,20 @@ static void ar9003_hw_detect_outlier(int *mp_coeff, int nmeasurement, /* find average (exclude max abs value) */ for (i = 0; i < nmeasurement; i++) { if ((abs(mp_coeff[i]) < abs(mp_max)) || - (abs(mp_coeff[i]) < abs(mp_min))) + (abs(mp_coeff[i]) < abs(mp_min))) { mp_avg += mp_coeff[i]; + mp_count++; + } } - mp_avg /= (nmeasurement - 1); + + /* + * finding mean magnitude/phase if possible, otherwise + * just use the last value as the mean + */ + if (mp_count) + mp_avg /= mp_count; + else + mp_avg = mp_coeff[nmeasurement - 1]; /* detect outlier */ if (abs(mp_max - mp_min) > max_delta) {