ath9k: enable 2GHz band only if the device supports it

Currently, the 2GHz band is enabled unconditionally, even if the device
does not support it.

Changes-licensed-under: ISC
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -976,7 +976,10 @@ int ath9k_hw_init(struct ath_hw *ah)
 		return r;
 
 	ath9k_hw_init_mode_gain_regs(ah);
-	ath9k_hw_fill_cap_info(ah);
+	r = ath9k_hw_fill_cap_info(ah);
+	if (r)
+		return r;
+
 	ath9k_hw_init_11a_eeprom_fix(ah);
 
 	r = ath9k_hw_init_macaddr(ah);
@@ -3112,7 +3115,7 @@ EXPORT_SYMBOL(ath9k_hw_set_sta_beacon_timers);
 /* HW Capabilities */
 /*******************/
 
-void ath9k_hw_fill_cap_info(struct ath_hw *ah)
+int ath9k_hw_fill_cap_info(struct ath_hw *ah)
 {
 	struct ath9k_hw_capabilities *pCap = &ah->caps;
 	struct ath_regulatory *regulatory = ath9k_hw_regulatory(ah);
@@ -3143,6 +3146,12 @@ void ath9k_hw_fill_cap_info(struct ath_hw *ah)
 	}
 
 	eeval = ah->eep_ops->get_eeprom(ah, EEP_OP_MODE);
+	if ((eeval & (AR5416_OPFLAGS_11G | AR5416_OPFLAGS_11A)) == 0) {
+		ath_print(common, ATH_DBG_FATAL,
+			  "no band has been marked as supported in EEPROM.\n");
+		return -EINVAL;
+	}
+
 	bitmap_zero(pCap->wireless_modes, ATH9K_MODE_MAX);
 
 	if (eeval & AR5416_OPFLAGS_11A) {
@@ -3306,6 +3315,8 @@ void ath9k_hw_fill_cap_info(struct ath_hw *ah)
 	} else {
 		btcoex_hw->scheme = ATH_BTCOEX_CFG_NONE;
 	}
+
+	return 0;
 }
 
 bool ath9k_hw_getcapability(struct ath_hw *ah, enum ath9k_capability_type type,

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

@@ -620,7 +620,7 @@ void ath9k_hw_detach(struct ath_hw *ah);
 int ath9k_hw_init(struct ath_hw *ah);
 int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 		   bool bChannelChange);
-void ath9k_hw_fill_cap_info(struct ath_hw *ah);
+int ath9k_hw_fill_cap_info(struct ath_hw *ah);
 bool ath9k_hw_getcapability(struct ath_hw *ah, enum ath9k_capability_type type,
 			    u32 capability, u32 *result);
 bool ath9k_hw_setcapability(struct ath_hw *ah, enum ath9k_capability_type type,

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

@@ -1793,6 +1793,7 @@ static int ath_init_softc(u16 devid, struct ath_softc *sc, u16 subsysid,
 
 	/* setup channels and rates */
 
+	if (test_bit(ATH9K_MODE_11G, sc->sc_ah->caps.wireless_modes)) {
 		sc->sbands[IEEE80211_BAND_2GHZ].channels = ath9k_2ghz_chantable;
 		sc->sbands[IEEE80211_BAND_2GHZ].band = IEEE80211_BAND_2GHZ;
 		sc->sbands[IEEE80211_BAND_2GHZ].n_channels =
@@ -1800,6 +1801,7 @@ static int ath_init_softc(u16 devid, struct ath_softc *sc, u16 subsysid,
 		sc->sbands[IEEE80211_BAND_2GHZ].bitrates = ath9k_legacy_rates;
 		sc->sbands[IEEE80211_BAND_2GHZ].n_bitrates =
 			ARRAY_SIZE(ath9k_legacy_rates);
+	}
 
 	if (test_bit(ATH9K_MODE_11A, sc->sc_ah->caps.wireless_modes)) {
 		sc->sbands[IEEE80211_BAND_5GHZ].channels = ath9k_5ghz_chantable;
@@ -1876,6 +1878,7 @@ void ath_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw)
 
 	hw->rate_control_algorithm = "ath9k_rate_control";
 
+	if (test_bit(ATH9K_MODE_11G, sc->sc_ah->caps.wireless_modes))
 		hw->wiphy->bands[IEEE80211_BAND_2GHZ] =
 			&sc->sbands[IEEE80211_BAND_2GHZ];
 	if (test_bit(ATH9K_MODE_11A, sc->sc_ah->caps.wireless_modes))
@@ -1916,9 +1919,12 @@ int ath_init_device(u16 devid, struct ath_softc *sc, u16 subsysid,
 	reg = &common->regulatory;
 
 	if (ah->caps.hw_caps & ATH9K_HW_CAP_HT) {
-		setup_ht_cap(sc, &sc->sbands[IEEE80211_BAND_2GHZ].ht_cap);
+		if (test_bit(ATH9K_MODE_11G, ah->caps.wireless_modes))
+			setup_ht_cap(sc,
+				     &sc->sbands[IEEE80211_BAND_2GHZ].ht_cap);
 		if (test_bit(ATH9K_MODE_11A, ah->caps.wireless_modes))
-			setup_ht_cap(sc, &sc->sbands[IEEE80211_BAND_5GHZ].ht_cap);
+			setup_ht_cap(sc,
+				     &sc->sbands[IEEE80211_BAND_5GHZ].ht_cap);
 	}
 
 	/* initialize tx/rx engine */