diff --git a/drivers/net/wireless/ath/ath9k/Kconfig b/drivers/net/wireless/ath/ath9k/Kconfig
index f68cb00..57b0a41 100644
--- a/drivers/net/wireless/ath/ath9k/Kconfig
+++ b/drivers/net/wireless/ath/ath9k/Kconfig
@@ -114,6 +114,25 @@ config ATH9K_DFS_CERTIFIED
 	  developed. At this point enabling this option won't do anything
 	  except increase code size.
 
+config ATH9K_49_GHZ_CHAN
+	bool "Support 4.9Ghz public safety channels on some devices"
+	depends on ATH9K && CFG80211_CERTIFICATION_ONUS
+	default n
+	---help---
+	  This option enables support for 4.9 GHz channels on AR9580.
+
+	  These are PUBLIC SAFETY CHANNELS and MUST NOT BE USED in most
+	  regulatory domains UNLESS YOU HAVE A FULL LICENSE for their use from
+	  your local radio regulator, e.g. the FCC or equivalent. Using these
+	  channels without proper authorisation may result in serious legal
+	  consequences.
+
+	  You will also have to build a regulatory database with these channels
+	  enabled to actually use them.
+
+	  If you are a distro kernel builder or have any doubt whatsoever about
+	  your legal ability to use these channels, say N.
+
 config ATH9K_DYNACK
 	bool "Atheros ath9k ACK timeout estimation algorithm (EXPERIMENTAL)"
 	depends on ATH9K
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 93b3793..d8744b5 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -954,7 +954,7 @@ struct ath_softc {
 	struct device *dev;
 
 	struct survey_info *cur_survey;
-	struct survey_info survey[ATH9K_NUM_CHANNELS];
+	struct survey_info survey[ATH9K_MAX_NUM_CHANNELS];
 
 	struct tasklet_struct intr_tq;
 	struct tasklet_struct bcon_tasklet;
diff --git a/drivers/net/wireless/ath/ath9k/common-init.c b/drivers/net/wireless/ath/ath9k/common-init.c
index 8b4f7fd..f6a495b 100644
--- a/drivers/net/wireless/ath/ath9k/common-init.c
+++ b/drivers/net/wireless/ath/ath9k/common-init.c
@@ -86,6 +86,24 @@ static const struct ieee80211_channel ath9k_5ghz_chantable[] = {
 	CHAN5G(5785, 35), /* Channel 157 */
 	CHAN5G(5805, 36), /* Channel 161 */
 	CHAN5G(5825, 37), /* Channel 165 */
+
+#ifdef ATH9K_49_GHZ_CHAN
+	/* 4.9Ghz channels, public safety channels, license is required in US
+	 * and most other regulatory domains!
+	 */
+	CHAN5G(4915, 38), /* Channel 183 */
+	CHAN5G(4920, 39), /* Channel 184 */
+	CHAN5G(4925, 40), /* Channel 185 */
+	CHAN5G(4935, 41), /* Channel 187 */
+	CHAN5G(4940, 42), /* Channel 188 */
+	CHAN5G(4945, 43), /* Channel 189 */
+	CHAN5G(4960, 44), /* Channel 192 */
+	CHAN5G(4970, 45), /* Channel 194 */
+	CHAN5G(4980, 46), /* Channel 196 */
+#define ATH9K_NUM_49GHZ_CHANNELS 9
+#else
+#define ATH9K_NUM_49GHZ_CHANNELS 0
+#endif
 };
 
 /* Atheros hardware rate code addition for short premble */
@@ -122,14 +140,31 @@ static struct ieee80211_rate ath9k_legacy_rates[] = {
 			 IEEE80211_RATE_SUPPORTS_10MHZ)),
 };
 
+static bool ath9k_49ghz_capable(struct ath_hw *ah)
+{
+#ifdef ATH9K_49_GHZ_CHAN
+	/* Seems AR9580 supports 4.9ghz, at least. */
+	switch (ah->hw_version.devid) {
+	case AR9300_DEVID_AR9580:
+		return true;
+	}
+#endif
+
+	return false;
+}
+
 int ath9k_cmn_init_channels_rates(struct ath_common *common)
 {
 	struct ath_hw *ah = (struct ath_hw *)common->ah;
 	void *channels;
+	int num_5ghz_chan = ARRAY_SIZE(ath9k_5ghz_chantable);
+
+	if (!ath9k_49ghz_capable(ah))
+		num_5ghz_chan -= ATH9K_NUM_49GHZ_CHANNELS;
 
 	BUILD_BUG_ON(ARRAY_SIZE(ath9k_2ghz_chantable) +
-		     ARRAY_SIZE(ath9k_5ghz_chantable) !=
-		     ATH9K_NUM_CHANNELS);
+		     ARRAY_SIZE(ath9k_5ghz_chantable) >
+		     ATH9K_MAX_NUM_CHANNELS);
 
 	if (ah->caps.hw_caps & ATH9K_HW_CAP_2GHZ) {
 		channels = devm_kzalloc(ah->dev,
@@ -149,17 +184,16 @@ int ath9k_cmn_init_channels_rates(struct ath_common *common)
 	}
 
 	if (ah->caps.hw_caps & ATH9K_HW_CAP_5GHZ) {
-		channels = devm_kzalloc(ah->dev,
-			sizeof(ath9k_5ghz_chantable), GFP_KERNEL);
+		int ch_sz = num_5ghz_chan * sizeof(ath9k_5ghz_chantable[0]);
+
+		channels = devm_kzalloc(ah->dev, ch_sz, GFP_KERNEL);
 		if (!channels)
 			return -ENOMEM;
 
-		memcpy(channels, ath9k_5ghz_chantable,
-		       sizeof(ath9k_5ghz_chantable));
+		memcpy(channels, ath9k_5ghz_chantable, ch_sz);
 		common->sbands[NL80211_BAND_5GHZ].channels = channels;
 		common->sbands[NL80211_BAND_5GHZ].band = NL80211_BAND_5GHZ;
-		common->sbands[NL80211_BAND_5GHZ].n_channels =
-			ARRAY_SIZE(ath9k_5ghz_chantable);
+		common->sbands[NL80211_BAND_5GHZ].n_channels = num_5ghz_chan;
 		common->sbands[NL80211_BAND_5GHZ].bitrates =
 			ath9k_legacy_rates + 4;
 		common->sbands[NL80211_BAND_5GHZ].n_bitrates =
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index 9cbca12..8115d86 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -73,7 +73,7 @@
 
 #define ATH9K_RSSI_BAD			-128
 
-#define ATH9K_NUM_CHANNELS	38
+#define ATH9K_MAX_NUM_CHANNELS	47
 
 /* Register read/write primitives */
 #define REG_WRITE(_ah, _reg, _val) \
@@ -777,7 +777,7 @@ struct ath_hw {
 	struct ath9k_hw_version hw_version;
 	struct ath9k_ops_config config;
 	struct ath9k_hw_capabilities caps;
-	struct ath9k_channel channels[ATH9K_NUM_CHANNELS];
+	struct ath9k_channel channels[ATH9K_MAX_NUM_CHANNELS];
 	struct ath9k_channel *curchan;
 
 	union {
