| Message ID | 1315320602-2815-1-git-send-email-rmanohar@qca.qualcomm.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
Hi Rajkumar, On Tue, Sep 6, 2011 at 7:50 AM, Rajkumar Manoharan <rmanohar@qca.qualcomm.com> wrote: > 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. > [...] > + /* > + * 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[i - 1]; Why use "i - 1" here instead of "nmeasurement - 1"? Seems more error-prone for later changes and harder to understand. -- Paul -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_calib.c b/drivers/net/wireless/ath/ath9k/ar9003_calib.c index ee3a8a2..6ec3e6d 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[i - 1]; /* detect outlier */ if (abs(mp_max - mp_min) > max_delta) {
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 <kaishi@qca.qualcomm.com> Reported-by: Paul Stewart <pstew@google.com> Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com> --- drivers/net/wireless/ath/ath9k/ar9003_calib.c | 17 +++++++++++++---- 1 files changed, 13 insertions(+), 4 deletions(-)