diff options
| author | Vasanthakumar Thiagarajan <vasanth@atheros.com> | 2010-11-10 13:03:14 (GMT) |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2010-11-16 21:37:06 (GMT) |
| commit | bc2068020bfa976efd425f3be590f58a012fd747 (patch) | |
| tree | 83eafebd48788d4af4fe2b4a5e449d479e7be5aa /drivers | |
| parent | 15cbbc44cc4abaaebc37caf0ec9410a3f83d1deb (diff) | |
| download | linux-fsl-qoriq-bc2068020bfa976efd425f3be590f58a012fd747.tar.xz | |
ath9k_hw: Add helper function for interpolation
Also round off interpolated values this would improve power
accuracy by 0.5dB in some cases.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/ar9003_eeprom.c | 48 |
1 files changed, 28 insertions, 20 deletions
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c index 5ffeda2..1b4e991 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c @@ -2982,6 +2982,16 @@ static int ath9k_hw_ar9300_check_eeprom(struct ath_hw *ah) return 0; } +static int interpolate(int x, int xa, int xb, int ya, int yb) +{ + int bf, factor, plus; + + bf = 2 * (yb - ya) * (x - xa) / (xb - xa); + factor = bf / 2; + plus = bf % 2; + return ya + factor + plus; +} + static u32 ath9k_hw_ar9300_get_eeprom(struct ath_hw *ah, enum eeprom_param param) { @@ -3614,7 +3624,7 @@ static int ar9003_hw_power_interpolate(int32_t x, if (hx == lx) y = ly; else /* interpolate */ - y = ly + (((x - lx) * (hy - ly)) / (hx - lx)); + y = interpolate(x, lx, hx, ly, hy); } else /* only low is good, use it */ y = ly; } else if (hhave) /* only high is good, use it */ @@ -4204,25 +4214,23 @@ static int ar9003_hw_calibration_apply(struct ath_hw *ah, int frequency) /* so is the high frequency, interpolate */ if (hfrequency[ichain] - frequency < 1000) { - correction[ichain] = lcorrection[ichain] + - (((frequency - lfrequency[ichain]) * - (hcorrection[ichain] - - lcorrection[ichain])) / - (hfrequency[ichain] - lfrequency[ichain])); - - temperature[ichain] = ltemperature[ichain] + - (((frequency - lfrequency[ichain]) * - (htemperature[ichain] - - ltemperature[ichain])) / - (hfrequency[ichain] - lfrequency[ichain])); - - voltage[ichain] = - lvoltage[ichain] + - (((frequency - - lfrequency[ichain]) * (hvoltage[ichain] - - lvoltage[ichain])) - / (hfrequency[ichain] - - lfrequency[ichain])); + correction[ichain] = interpolate(frequency, + lfrequency[ichain], + hfrequency[ichain], + lcorrection[ichain], + hcorrection[ichain]); + + temperature[ichain] = interpolate(frequency, + lfrequency[ichain], + hfrequency[ichain], + ltemperature[ichain], + htemperature[ichain]); + + voltage[ichain] = interpolate(frequency, + lfrequency[ichain], + hfrequency[ichain], + lvoltage[ichain], + hvoltage[ichain]); } /* only low is good, use it */ else { |