iw: add patch to support 802.11j frequencies

A similar change was recently merged in iw commit
58b46da26ab9b5ff31c7033e175351eb1301d9af

Signed-off-by: Bruno Randolf <br1@einfach.org>

SVN-Revision: 38449

package/network/utils/iw/patches/140-freq-11j.patch

@@ -0,0 +1,85 @@
+--- a/iw.h
++++ b/iw.h
+@@ -146,7 +146,7 @@ void print_ht_capability(__u16 cap);
+ 
+ const char *iftype_name(enum nl80211_iftype iftype);
+ const char *command_name(enum nl80211_commands cmd);
+-int ieee80211_channel_to_frequency(int chan);
++int ieee80211_channel_to_frequency(int chan, enum nl80211_band band);
+ int ieee80211_frequency_to_channel(int freq);
+ 
+ void print_ssid_escaped(const uint8_t len, const uint8_t *data);
+--- a/phy.c
++++ b/phy.c
+@@ -66,8 +66,12 @@ static int handle_freqchan(struct nl_msg
+ 	if (*end)
+ 		return 1;
+ 
+-	if (chan)
+-		freq = ieee80211_channel_to_frequency(freq);
++	if (chan) {
++		enum nl80211_band band;
++		band = freq <= 14 ? NL80211_BAND_2GHZ : NL80211_BAND_5GHZ;
++		freq = ieee80211_channel_to_frequency(freq, band);
++	}
++
+ 
+ 	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_FREQ, freq);
+ 	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_CHANNEL_TYPE, htval);
+--- a/util.c
++++ b/util.c
+@@ -248,31 +248,37 @@ const char *command_name(enum nl80211_co
+ 	return cmdbuf;
+ }
+ 
+-int ieee80211_channel_to_frequency(int chan)
++int ieee80211_channel_to_frequency(int chan, enum nl80211_band band)
+ {
+-	if (chan < 14)
+-		return 2407 + chan * 5;
+-
+-	if (chan == 14)
+-		return 2484;
+-
+-	/* FIXME: dot11ChannelStartingFactor (802.11-2007 17.3.8.3.2) */
+-	return (chan + 1000) * 5;
++	/* see 802.11-2007 17.3.8.3.2 and Annex J
++	 * there are overlapping channel numbers in 5GHz and 2GHz bands */
++	if (band == NL80211_BAND_5GHZ) {
++		if (chan >= 182 && chan <= 196)
++			return 4000 + chan * 5;
++		else
++			return 5000 + chan * 5;
++	} else { /* NL80211_BAND_2GHZ */
++		if (chan == 14)
++			return 2484;
++		else if (chan < 14)
++			return 2407 + chan * 5;
++		else
++			return 0; /* not supported */
++	}
+ }
+ 
+ int ieee80211_frequency_to_channel(int freq)
+ {
++	/* see 802.11-2007 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: dot11ChannelStartingFactor (802.11-2007 17.3.8.3.2) */
+-	if (freq < 45000)
+-		return freq/5 - 1000;
+-
+-	if (freq >= 58320 && freq <= 64800)
++	else if (freq >= 4910 && freq <= 4980)
++		return (freq - 4000) / 5;
++	else if (freq < 45000)
++		return (freq - 5000) / 5;
++	else if (freq >= 58320 && freq <= 64800)
+ 		return (freq - 56160) / 2160;
+ 
+ 	return 0;