ath9k: fix TX power reporting on AR9003 chips

The current code unconditionally reads the target
power values for all modes from the EEPROM. However
In 'ar9003_hw_set_power_per_rate_table' the regulatory
caps are applied only on a mode specific subset of the
power values.

The reported TX power level is calculated from the
maximum of the power values. Because some of these
values are uncapped in certain cases, the reported
TX power will be wrong.

On the older chipset, we don't have such problems
because only the mode specific subset of the power
levels are retrieved from the EEPROM on those. Do
the same for the AR9003 chips to fix the issue.

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

drivers/net/wireless/ath/ath9k/ar9003_eeprom.c

@@ -4281,18 +4281,10 @@ static int ar9003_hw_tx_power_regwrite(struct ath_hw *ah, u8 * pPwrArray)
 #undef POW_SM
 }
 
-static void ar9003_hw_set_target_power_eeprom(struct ath_hw *ah, u16 freq,
-					      u8 *targetPowerValT2)
+static void ar9003_hw_get_legacy_target_powers(struct ath_hw *ah, u16 freq,
+					       u8 *targetPowerValT2,
+					       bool is2GHz)
 {
-	/* XXX: hard code for now, need to get from eeprom struct */
-	u8 ht40PowerIncForPdadc = 0;
-	bool is2GHz = false;
-	unsigned int i = 0;
-	struct ath_common *common = ath9k_hw_common(ah);
-
-	if (freq < 4000)
-		is2GHz = true;
-
 	targetPowerValT2[ALL_TARGET_LEGACY_6_24] =
 	    ar9003_hw_eeprom_get_tgt_pwr(ah, LEGACY_TARGET_RATE_6_24, freq,
 					 is2GHz);
@@ -4305,6 +4297,11 @@ static void ar9003_hw_set_target_power_eeprom(struct ath_hw *ah, u16 freq,
 	targetPowerValT2[ALL_TARGET_LEGACY_54] =
 	    ar9003_hw_eeprom_get_tgt_pwr(ah, LEGACY_TARGET_RATE_54, freq,
 					 is2GHz);
+}
+
+static void ar9003_hw_get_cck_target_powers(struct ath_hw *ah, u16 freq,
+					    u8 *targetPowerValT2)
+{
 	targetPowerValT2[ALL_TARGET_LEGACY_1L_5L] =
 	    ar9003_hw_eeprom_get_cck_tgt_pwr(ah, LEGACY_TARGET_RATE_1L_5L,
 					     freq);
@@ -4314,6 +4311,11 @@ static void ar9003_hw_set_target_power_eeprom(struct ath_hw *ah, u16 freq,
 	    ar9003_hw_eeprom_get_cck_tgt_pwr(ah, LEGACY_TARGET_RATE_11L, freq);
 	targetPowerValT2[ALL_TARGET_LEGACY_11S] =
 	    ar9003_hw_eeprom_get_cck_tgt_pwr(ah, LEGACY_TARGET_RATE_11S, freq);
+}
+
+static void ar9003_hw_get_ht20_target_powers(struct ath_hw *ah, u16 freq,
+					     u8 *targetPowerValT2, bool is2GHz)
+{
 	targetPowerValT2[ALL_TARGET_HT20_0_8_16] =
 	    ar9003_hw_eeprom_get_ht20_tgt_pwr(ah, HT_TARGET_RATE_0_8_16, freq,
 					      is2GHz);
@@ -4356,6 +4358,16 @@ static void ar9003_hw_set_target_power_eeprom(struct ath_hw *ah, u16 freq,
 	targetPowerValT2[ALL_TARGET_HT20_23] =
 	    ar9003_hw_eeprom_get_ht20_tgt_pwr(ah, HT_TARGET_RATE_23, freq,
 					      is2GHz);
+}
+
+static void ar9003_hw_get_ht40_target_powers(struct ath_hw *ah,
+						   u16 freq,
+						   u8 *targetPowerValT2,
+						   bool is2GHz)
+{
+	/* XXX: hard code for now, need to get from eeprom struct */
+	u8 ht40PowerIncForPdadc = 0;
+
 	targetPowerValT2[ALL_TARGET_HT40_0_8_16] =
 	    ar9003_hw_eeprom_get_ht40_tgt_pwr(ah, HT_TARGET_RATE_0_8_16, freq,
 					      is2GHz) + ht40PowerIncForPdadc;
@@ -4399,6 +4411,26 @@ static void ar9003_hw_set_target_power_eeprom(struct ath_hw *ah, u16 freq,
 	targetPowerValT2[ALL_TARGET_HT40_23] =
 	    ar9003_hw_eeprom_get_ht40_tgt_pwr(ah, HT_TARGET_RATE_23, freq,
 					      is2GHz) + ht40PowerIncForPdadc;
+}
+
+static void ar9003_hw_get_target_power_eeprom(struct ath_hw *ah,
+					      struct ath9k_channel *chan,
+					      u8 *targetPowerValT2)
+{
+	bool is2GHz = IS_CHAN_2GHZ(chan);
+	unsigned int i = 0;
+	struct ath_common *common = ath9k_hw_common(ah);
+	u16 freq = chan->channel;
+
+	if (is2GHz)
+		ar9003_hw_get_cck_target_powers(ah, freq, targetPowerValT2);
+
+	ar9003_hw_get_legacy_target_powers(ah, freq, targetPowerValT2, is2GHz);
+	ar9003_hw_get_ht20_target_powers(ah, freq, targetPowerValT2, is2GHz);
+
+	if (IS_CHAN_HT40(chan))
+		ar9003_hw_get_ht40_target_powers(ah, freq, targetPowerValT2,
+						 is2GHz);
 
 	for (i = 0; i < ar9300RateSize; i++) {
 		ath_dbg(common, EEPROM, "TPC[%02d] 0x%08x\n",
@@ -4778,9 +4810,6 @@ static void ar9003_hw_set_power_per_rate_table(struct ath_hw *ah,
 	scaledPower = ath9k_hw_get_scaled_power(ah, powerLimit,
 						antenna_reduction);
 
-	/*
-	 * Get target powers from EEPROM - our baseline for TX Power
-	 */
 	if (is2ghz) {
 		/* Setup for CTL modes */
 		/* CTL_11B, CTL_11G, CTL_2GHT20 */
@@ -4952,7 +4981,12 @@ static void ath9k_hw_ar9300_set_txpower(struct ath_hw *ah,
 	unsigned int i = 0, paprd_scale_factor = 0;
 	u8 pwr_idx, min_pwridx = 0;
 
-	ar9003_hw_set_target_power_eeprom(ah, chan->channel, targetPowerValT2);
+	memset(targetPowerValT2, 0 , sizeof(targetPowerValT2));
+
+	/*
+	 * Get target powers from EEPROM - our baseline for TX Power
+	 */
+	ar9003_hw_get_target_power_eeprom(ah, chan, targetPowerValT2);
 
 	if (ah->eep_ops->get_eeprom(ah, EEP_PAPRD)) {
 		if (IS_CHAN_2GHZ(chan))