ath9k_hw: clean up tx power handling

The code for handling various restrictions concerning regulatory limits,
antenna gain, etc. is very convoluted and duplicated across various
EEPROM parsing implementations, making it hard to review.

This patch partially cleans up the mess by unifying regulatory limit
handling in one function and simplifying handling of antenna gain.
It also removes unused transmit power scaling arrays from the EEPROM code,
which belonged to an unimplemented API that isn't supposed to be in
the driver anyway.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 5 insertions, 22 deletions

diff --git a/drivers/net/wireless/ath/ath9k/eeprom_4k.c b/drivers/net/wireless/ath/ath9k/eeprom_4k.c
index 303560e..ab6811d 100644
--- a/drivers/net/wireless/ath/ath9k/eeprom_4k.c
+++ b/drivers/net/wireless/ath/ath9k/eeprom_4k.c
@@ -350,6 +350,8 @@ static u32 ath9k_hw_4k_get_eeprom(struct ath_hw *ah,
 		return pModal->antdiv_ctl1;
 	case EEP_TXGAIN_TYPE:
 		return pBase->txGainType;
+	case EEP_ANTENNA_GAIN_2G:
+		return pModal->antennaGainCh[0];
 	default:
 		return 0;
 	}
@@ -462,8 +464,7 @@ static void ath9k_hw_set_4k_power_per_rate_table(struct ath_hw *ah,
 						 struct ath9k_channel *chan,
 						 int16_t *ratesArray,
 						 u16 cfgCtl,
-						 u16 AntennaReduction,
-						 u16 twiceMaxRegulatoryPower,
+						 u16 antenna_reduction,
 						 u16 powerLimit)
 {
 #define CMP_TEST_GRP \
@@ -472,20 +473,16 @@ static void ath9k_hw_set_4k_power_per_rate_table(struct ath_hw *ah,
 	|| (((cfgCtl & ~CTL_MODE_M) | (pCtlMode[ctlMode] & CTL_MODE_M)) == \
 	    ((pEepData->ctlIndex[i] & CTL_MODE_M) | SD_NO_CTL))
 
-	struct ath_regulatory *regulatory = ath9k_hw_regulatory(ah);
 	int i;
-	int16_t twiceLargestAntenna;
 	u16 twiceMinEdgePower;
 	u16 twiceMaxEdgePower = MAX_RATE_POWER;
-	u16 scaledPower = 0, minCtlPower, maxRegAllowedPower;
+	u16 scaledPower = 0, minCtlPower;
 	u16 numCtlModes;
 	const u16 *pCtlMode;
 	u16 ctlMode, freq;
 	struct chan_centers centers;
 	struct cal_ctl_data_4k *rep;
 	struct ar5416_eeprom_4k *pEepData = &ah->eeprom.map4k;
-	static const u16 tpScaleReductionTable[5] =
-		{ 0, 3, 6, 9, MAX_RATE_POWER };
 	struct cal_target_power_leg targetPowerOfdm, targetPowerCck = {
 		0, { 0, 0, 0, 0}
 	};
@@ -503,19 +500,7 @@ static void ath9k_hw_set_4k_power_per_rate_table(struct ath_hw *ah,
 
 	ath9k_hw_get_channel_centers(ah, chan, &centers);
 
-	twiceLargestAntenna = pEepData->modalHeader.antennaGainCh[0];
-	twiceLargestAntenna = (int16_t)min(AntennaReduction -
-					   twiceLargestAntenna, 0);
-
-	maxRegAllowedPower = twiceMaxRegulatoryPower + twiceLargestAntenna;
-	if (regulatory->tp_scale != ATH9K_TP_SCALE_MAX) {
-		maxRegAllowedPower -=
-			(tpScaleReductionTable[(regulatory->tp_scale)] * 2);
-	}
-
-	scaledPower = min(powerLimit, maxRegAllowedPower);
-	scaledPower = max((u16)0, scaledPower);
-
+	scaledPower = powerLimit - antenna_reduction;
 	numCtlModes = ARRAY_SIZE(ctlModesFor11g) - SUB_NUM_CTL_MODES_AT_2G_40;
 	pCtlMode = ctlModesFor11g;
 
@@ -671,7 +656,6 @@ static void ath9k_hw_4k_set_txpower(struct ath_hw *ah,
 				    struct ath9k_channel *chan,
 				    u16 cfgCtl,
 				    u8 twiceAntennaReduction,
-				    u8 twiceMaxRegulatoryPower,
 				    u8 powerLimit, bool test)
 {
 	struct ath_regulatory *regulatory = ath9k_hw_regulatory(ah);
@@ -691,7 +675,6 @@ static void ath9k_hw_4k_set_txpower(struct ath_hw *ah,
 	ath9k_hw_set_4k_power_per_rate_table(ah, chan,
 					     &ratesArray[0], cfgCtl,
 					     twiceAntennaReduction,
-					     twiceMaxRegulatoryPower,
 					     powerLimit);
 
 	ath9k_hw_set_4k_power_cal_table(ah, chan);