diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index f28b86c5d346dd967e53cb3c3d06fed91184220b..6580df2f74433495019c22b744d02f96a323d4a3 100644
--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -1088,9 +1088,18 @@ ath5k_mode_setup(struct ath5k_softc *sc)
 static inline int
 ath5k_hw_to_driver_rix(struct ath5k_softc *sc, int hw_rix)
 {
-	WARN(hw_rix < 0 || hw_rix >= AR5K_MAX_RATES,
-			"hw_rix out of bounds: %x\n", hw_rix);
-	return sc->rate_idx[sc->curband->band][hw_rix];
+	int rix;
+
+	/* return base rate on errors */
+	if (WARN(hw_rix < 0 || hw_rix >= AR5K_MAX_RATES,
+			"hw_rix out of bounds: %x\n", hw_rix))
+		return 0;
+
+	rix = sc->rate_idx[sc->curband->band][hw_rix];
+	if (WARN(rix < 0, "invalid hw_rix: %x\n", hw_rix))
+		rix = 0;
+
+	return rix;
 }
 
 /***************\
diff --git a/drivers/net/wireless/ath5k/base.h b/drivers/net/wireless/ath5k/base.h
index 20e0d14b41eca221710c9fc6fa981c239f31c5f4..822956114cd767781ec6546814d6c2cf8f0047c0 100644
--- a/drivers/net/wireless/ath5k/base.h
+++ b/drivers/net/wireless/ath5k/base.h
@@ -112,7 +112,7 @@ struct ath5k_softc {
 	struct ieee80211_supported_band sbands[IEEE80211_NUM_BANDS];
 	struct ieee80211_channel channels[ATH_CHAN_MAX];
 	struct ieee80211_rate	rates[IEEE80211_NUM_BANDS][AR5K_MAX_RATES];
-	u8			rate_idx[IEEE80211_NUM_BANDS][AR5K_MAX_RATES];
+	s8			rate_idx[IEEE80211_NUM_BANDS][AR5K_MAX_RATES];
 	enum nl80211_iftype	opmode;
 	struct ath5k_hw		*ah;		/* Atheros HW */