diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index 8649581..fe3c10e 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -69,15 +69,21 @@
 					      int16_t *nfarray)
 {
 	struct ath_common *common = ath9k_hw_common(ah);
+	struct ieee80211_conf *conf = &common->hw->conf;
 	struct ath_nf_limits *limit;
 	struct ath9k_nfcal_hist *h;
 	bool high_nf_mid = false;
+	u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
 	int i;
 
 	h = cal->nfCalHist;
 	limit = ath9k_hw_get_nf_limits(ah, ah->curchan);
 
 	for (i = 0; i < NUM_NF_READINGS; i++) {
+		if (!(chainmask & (1 << i)) ||
+		    ((i >= AR5416_MAX_CHAINS) && !conf_is_ht40(conf)))
+			continue;
+
 		h[i].nfCalBuffer[h[i].currIndex] = nfarray[i];
 
 		if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX)
@@ -225,6 +231,7 @@
 	int32_t val;
 	u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
 	struct ath_common *common = ath9k_hw_common(ah);
+	struct ieee80211_conf *conf = &common->hw->conf;
 	s16 default_nf = ath9k_hw_get_default_nf(ah, chan);
 
 	if (ah->caldata)
@@ -234,6 +241,9 @@
 		if (chainmask & (1 << i)) {
 			s16 nfval;
 
+			if ((i >= AR5416_MAX_CHAINS) && !conf_is_ht40(conf))
+				continue;
+
 			if (h)
 				nfval = h[i].privNF;
 			else
@@ -293,6 +303,9 @@
 	ENABLE_REGWRITE_BUFFER(ah);
 	for (i = 0; i < NUM_NF_READINGS; i++) {
 		if (chainmask & (1 << i)) {
+			if ((i >= AR5416_MAX_CHAINS) && !conf_is_ht40(conf))
+				continue;
+
 			val = REG_READ(ah, ah->nf_regs[i]);
 			val &= 0xFFFFFE00;
 			val |= (((u32) (-50) << 1) & 0x1ff);