diff --git a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
index 0ca7635d0669c276683762f85cd493b3a21e5b87..ff8150e46f0e969a159d3b481cee5752432fcace 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
@@ -4645,10 +4645,16 @@ static void ar9003_hw_set_power_per_rate_table(struct ath_hw *ah,
 	case 1:
 		break;
 	case 2:
-		scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+		if (scaledPower > REDUCE_SCALED_POWER_BY_TWO_CHAIN)
+			scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+		else
+			scaledPower = 0;
 		break;
 	case 3:
-		scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+		if (scaledPower > REDUCE_SCALED_POWER_BY_THREE_CHAIN)
+			scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+		else
+			scaledPower = 0;
 		break;
 	}
 
diff --git a/drivers/net/wireless/ath/ath9k/eeprom_9287.c b/drivers/net/wireless/ath/ath9k/eeprom_9287.c
index 7856f0d4512d6292a1a70ef3f4f98360666f1847..343fc9f946dbc7dcb6b613cad3cff3b2bb12e84e 100644
--- a/drivers/net/wireless/ath/ath9k/eeprom_9287.c
+++ b/drivers/net/wireless/ath/ath9k/eeprom_9287.c
@@ -524,10 +524,16 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
 	case 1:
 		break;
 	case 2:
-		scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+		if (scaledPower > REDUCE_SCALED_POWER_BY_TWO_CHAIN)
+			scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+		else
+			scaledPower = 0;
 		break;
 	case 3:
-		scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+		if (scaledPower > REDUCE_SCALED_POWER_BY_THREE_CHAIN)
+			scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+		else
+			scaledPower = 0;
 		break;
 	}
 	scaledPower = max((u16)0, scaledPower);