1 files changed, 22 insertions, 14 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 7620ae2fcf18..4ed065d8bb51 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -29,29 +29,37 @@ ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
 }
 EXPORT_SYMBOL(ieee80211_get_response_rate);
 
-int ieee80211_channel_to_frequency(int chan)
+int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
 {
-        if (chan < 14)
-                return 2407 + chan * 5;
-
-        if (chan == 14)
-                return 2484;
-
-        /* FIXME: 802.11j 17.3.8.3.2 */
-        return (chan + 1000) * 5;
+        /* see 802.11 17.3.8.3.2 and Annex J
+         * there are overlapping channel numbers in 5GHz and 2GHz bands */
+        if (band == IEEE80211_BAND_5GHZ) {
+                if (chan >= 182 && chan <= 196)
+                        return 4000 + chan * 5;
+                else
+                        return 5000 + chan * 5;
+        } else { /* IEEE80211_BAND_2GHZ */
+                if (chan == 14)
+                        return 2484;
+                else if (chan < 14)
+                        return 2407 + chan * 5;
+                else
+                        return 0; /* not supported */
+        }
 }
 EXPORT_SYMBOL(ieee80211_channel_to_frequency);
 
 int ieee80211_frequency_to_channel(int freq)
 {
+        /* see 802.11 17.3.8.3.2 and Annex J */
         if (freq == 2484)
                 return 14;
-
-        if (freq < 2484)
+        else if (freq < 2484)
                 return (freq - 2407) / 5;
-
-        /* FIXME: 802.11j 17.3.8.3.2 */
-        return freq/5 - 1000;
+        else if (freq >= 4910 && freq <= 4980)
+                return (freq - 4000) / 5;
+        else
+                return (freq - 5000) / 5;
 }
 EXPORT_SYMBOL(ieee80211_frequency_to_channel);