iw: sync frequency to channel mapping with kernel

Use ieee80211_frequency_to_channel() and ieee80211_channel_to_frequency() as in
the current kernel. This is necessary to properly print the channel numbers for
4.9GHz channels which can be used in Japan.

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

diff --git a/iw.h b/iw.h
index 854d356ef783c2015fd0b1c17cbe458bbf5877f9..317f0a6e1372ec9666c8edfc35bfed32e6ec3d18 100644 (file)
--- a/iw.h
+++ b/iw.h
@@ -148,7 +148,7 @@ void print_vht_info(__u32 capa, const __u8 *mcs);
 char *channel_width_name(enum nl80211_chan_width width);
 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);

diff --git a/phy.c b/phy.c
index 7f8ce26a70b0290c265e0278151b5d854fda46ea..68f40f6faefcc1f59591b2f764c699582940f1ab 100644 (file)
--- a/phy.c
+++ b/phy.c
@@ -113,8 +113,11 @@ static int handle_freqchan(struct nl_msg *msg, bool chan,
        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);
 

diff --git a/util.c b/util.c
index e3d0c270ac446ac604d06e6350a43b0c5582eea0..4542749a18bdd66d67fd79c08b26b57ca0c85f7d 100644 (file)
--- a/util.c
+++ b/util.c
@@ -260,34 +260,50 @@ const char *command_name(enum nl80211_commands cmd)
        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 17.3.8.3.2 and Annex J
+        * there are overlapping channel numbers in 5GHz and 2GHz bands */
+       if (chan <= 0)
+               return 0; /* not supported */
+       switch (band) {
+       case NL80211_BAND_2GHZ:
+               if (chan == 14)
+                       return 2484;
+               else if (chan < 14)
+                       return 2407 + chan * 5;
+               break;
+       case NL80211_BAND_5GHZ:
+               if (chan >= 182 && chan <= 196)
+                       return 4000 + chan * 5;
+               else
+                       return 5000 + chan * 5;
+               break;
+       case NL80211_BAND_60GHZ:
+               if (chan < 5)
+                       return 56160 + chan * 2160;
+               break;
+       default:
+               ;
+       }
+       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) /* DMG band lower limit */
+               return (freq - 5000) / 5;
+       else if (freq >= 58320 && freq <= 64800)
                return (freq - 56160) / 2160;
-
-       return 0;
+       else
+               return 0;
 }
 
 void print_ssid_escaped(const uint8_t len, const uint8_t *data)