Also round off interpolated values this would improve power
accuracy by 0.5dB in some cases.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@xxxxxxxxxxx>
---
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 {
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
