ath9k: fix ANI operation in AP mode

ath9k_ani_reset (which is called at reset time) uses a state variable
ani->update_ani to prevent the ANI noise immunity state on the operating
channel from being overwritten by background scans. Unfortunately this
is also being set for AP mode, since it's mixed with code that is only
supposed to change the default settings after a reset.

In AP mode this has the side effect of having ANI run, but being unable to
change its runtime noise immunity level, making it effectively useless.

Fix this by getting rid of ani->update_ani and passing a parameter to
ath9k_hw_set_ofdm_nil and ath9k_hw_set_cck_nil instead.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -140,7 +140,8 @@ static void ath9k_ani_restart(struct ath_hw *ah)
 }
 
 /* Adjust the OFDM Noise Immunity Level */
-static void ath9k_hw_set_ofdm_nil(struct ath_hw *ah, u8 immunityLevel)
+static void ath9k_hw_set_ofdm_nil(struct ath_hw *ah, u8 immunityLevel,
+				  bool scan)
 {
 	struct ar5416AniState *aniState = &ah->curchan->ani;
 	struct ath_common *common = ath9k_hw_common(ah);
@@ -153,7 +154,7 @@ static void ath9k_hw_set_ofdm_nil(struct ath_hw *ah, u8 immunityLevel)
 		immunityLevel, BEACON_RSSI(ah),
 		aniState->rssiThrLow, aniState->rssiThrHigh);
 
-	if (aniState->update_ani)
+	if (!scan)
 		aniState->ofdmNoiseImmunityLevel = immunityLevel;
 
 	entry_ofdm = &ofdm_level_table[aniState->ofdmNoiseImmunityLevel];
@@ -199,13 +200,14 @@ static void ath9k_hw_ani_ofdm_err_trigger(struct ath_hw *ah)
 	aniState = &ah->curchan->ani;
 
 	if (aniState->ofdmNoiseImmunityLevel < ATH9K_ANI_OFDM_MAX_LEVEL)
-		ath9k_hw_set_ofdm_nil(ah, aniState->ofdmNoiseImmunityLevel + 1);
+		ath9k_hw_set_ofdm_nil(ah, aniState->ofdmNoiseImmunityLevel + 1, false);
 }
 
 /*
  * Set the ANI settings to match an CCK level.
  */
-static void ath9k_hw_set_cck_nil(struct ath_hw *ah, u_int8_t immunityLevel)
+static void ath9k_hw_set_cck_nil(struct ath_hw *ah, u_int8_t immunityLevel,
+				 bool scan)
 {
 	struct ar5416AniState *aniState = &ah->curchan->ani;
 	struct ath_common *common = ath9k_hw_common(ah);
@@ -222,7 +224,7 @@ static void ath9k_hw_set_cck_nil(struct ath_hw *ah, u_int8_t immunityLevel)
 	    immunityLevel > ATH9K_ANI_CCK_MAX_LEVEL_LOW_RSSI)
 		immunityLevel = ATH9K_ANI_CCK_MAX_LEVEL_LOW_RSSI;
 
-	if (aniState->update_ani)
+	if (!scan)
 		aniState->cckNoiseImmunityLevel = immunityLevel;
 
 	entry_ofdm = &ofdm_level_table[aniState->ofdmNoiseImmunityLevel];
@@ -254,7 +256,8 @@ static void ath9k_hw_ani_cck_err_trigger(struct ath_hw *ah)
 	aniState = &ah->curchan->ani;
 
 	if (aniState->cckNoiseImmunityLevel < ATH9K_ANI_CCK_MAX_LEVEL)
-		ath9k_hw_set_cck_nil(ah, aniState->cckNoiseImmunityLevel + 1);
+		ath9k_hw_set_cck_nil(ah, aniState->cckNoiseImmunityLevel + 1,
+				     false);
 }
 
 /*
@@ -270,13 +273,15 @@ static void ath9k_hw_ani_lower_immunity(struct ath_hw *ah)
 	/* lower OFDM noise immunity */
 	if (aniState->ofdmNoiseImmunityLevel > 0 &&
 	    (aniState->ofdmsTurn || aniState->cckNoiseImmunityLevel == 0)) {
-		ath9k_hw_set_ofdm_nil(ah, aniState->ofdmNoiseImmunityLevel - 1);
+		ath9k_hw_set_ofdm_nil(ah, aniState->ofdmNoiseImmunityLevel - 1,
+				      false);
 		return;
 	}
 
 	/* lower CCK noise immunity */
 	if (aniState->cckNoiseImmunityLevel > 0)
-		ath9k_hw_set_cck_nil(ah, aniState->cckNoiseImmunityLevel - 1);
+		ath9k_hw_set_cck_nil(ah, aniState->cckNoiseImmunityLevel - 1,
+				     false);
 }
 
 /*
@@ -338,7 +343,6 @@ void ath9k_ani_reset(struct ath_hw *ah, bool is_scanning)
 				aniState->ofdmNoiseImmunityLevel,
 				aniState->cckNoiseImmunityLevel);
 
-			aniState->update_ani = false;
 			ofdm_nil = ATH9K_ANI_OFDM_DEF_LEVEL;
 			cck_nil = ATH9K_ANI_CCK_DEF_LEVEL;
 		}
@@ -354,11 +358,9 @@ void ath9k_ani_reset(struct ath_hw *ah, bool is_scanning)
 			is_scanning,
 			aniState->ofdmNoiseImmunityLevel,
 			aniState->cckNoiseImmunityLevel);
-
-			aniState->update_ani = true;
 	}
-	ath9k_hw_set_ofdm_nil(ah, ofdm_nil);
-	ath9k_hw_set_cck_nil(ah, cck_nil);
+	ath9k_hw_set_ofdm_nil(ah, ofdm_nil, is_scanning);
+	ath9k_hw_set_cck_nil(ah, cck_nil, is_scanning);
 
 	/*
 	 * enable phy counters if hw supports or if not, enable phy
@@ -534,7 +536,6 @@ void ath9k_hw_ani_init(struct ath_hw *ah)
 		ani->ofdmWeakSigDetect = ATH9K_ANI_USE_OFDM_WEAK_SIG;
 		ani->cckNoiseImmunityLevel = ATH9K_ANI_CCK_DEF_LEVEL;
 		ani->ofdmNoiseImmunityLevel = ATH9K_ANI_OFDM_DEF_LEVEL;
-		ani->update_ani = false;
 	}
 
 	/*

drivers/net/wireless/ath/ath9k/ani.h

@@ -114,7 +114,6 @@ struct ar5416AniState {
 	u8 firstepLevel;
 	u8 ofdmWeakSigDetect;
 	u8 cckWeakSigThreshold;
-	bool update_ani;
 	u32 listenTime;
 	int32_t rssiThrLow;
 	int32_t rssiThrHigh;