wireless: report reasonable bitrate for MCS rates through wext

Previously, cfg80211 had reported "0" for MCS (i.e. 802.11n) bitrates
through the wireless extensions interface.  However, nl80211 was
converting MCS rates into a reasonable bitrate number.  This patch moves
the nl80211 code to cfg80211 where it is now shared between both the
nl80211 interface and the wireless extensions interface.

Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 38 insertions, 39 deletions

diff --git a/net/wireless/core.h b/net/wireless/core.h
index 4ef3efc94106..35b712127143 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -378,6 +378,8 @@ int rdev_set_freq(struct cfg80211_registered_device *rdev,
                   struct wireless_dev *for_wdev,
                   int freq, enum nl80211_channel_type channel_type);
 
+u16 cfg80211_calculate_bitrate(struct rate_info *rate);
+
 #ifdef CONFIG_CFG80211_DEVELOPER_WARNINGS
 #define CFG80211_DEV_WARN_ON(cond)      WARN_ON(cond)
 #else
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index a6028433e3a0..7cb0d647fc34 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1637,39 +1637,6 @@ static int parse_station_flags(struct genl_info *info,
         return 0;
 }
 
-static u16 nl80211_calculate_bitrate(struct rate_info *rate)
-{
-        int modulation, streams, bitrate;
-
-        if (!(rate->flags & RATE_INFO_FLAGS_MCS))
-                return rate->legacy;
-
-        /* the formula below does only work for MCS values smaller than 32 */
-        if (rate->mcs >= 32)
-                return 0;
-
-        modulation = rate->mcs & 7;
-        streams = (rate->mcs >> 3) + 1;
-
-        bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
-                        13500000 : 6500000;
-
-        if (modulation < 4)
-                bitrate *= (modulation + 1);
-        else if (modulation == 4)
-                bitrate *= (modulation + 2);
-        else
-                bitrate *= (modulation + 3);
-
-        bitrate *= streams;
-
-        if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
-                bitrate = (bitrate / 9) * 10;
-
-        /* do NOT round down here */
-        return (bitrate + 50000) / 100000;
-}
-
 static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
                                 int flags, struct net_device *dev,
                                 u8 *mac_addr, struct station_info *sinfo)
@@ -1716,8 +1683,8 @@ static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
                 if (!txrate)
                         goto nla_put_failure;
 
-                /* nl80211_calculate_bitrate will return 0 for mcs >= 32 */
-                bitrate = nl80211_calculate_bitrate(&sinfo->txrate);
+                /* cfg80211_calculate_bitrate will return 0 for mcs >= 32 */
+                bitrate = cfg80211_calculate_bitrate(&sinfo->txrate);
                 if (bitrate > 0)
                         NLA_PUT_U16(msg, NL80211_RATE_INFO_BITRATE, bitrate);
 
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 59361fdcb5d0..a3c841a255db 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -720,3 +720,36 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 
         return err;
 }
+
+u16 cfg80211_calculate_bitrate(struct rate_info *rate)
+{
+        int modulation, streams, bitrate;
+
+        if (!(rate->flags & RATE_INFO_FLAGS_MCS))
+                return rate->legacy;
+
+        /* the formula below does only work for MCS values smaller than 32 */
+        if (rate->mcs >= 32)
+                return 0;
+
+        modulation = rate->mcs & 7;
+        streams = (rate->mcs >> 3) + 1;
+
+        bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
+                        13500000 : 6500000;
+
+        if (modulation < 4)
+                bitrate *= (modulation + 1);
+        else if (modulation == 4)
+                bitrate *= (modulation + 2);
+        else
+                bitrate *= (modulation + 3);
+
+        bitrate *= streams;
+
+        if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
+                bitrate = (bitrate / 9) * 10;
+
+        /* do NOT round down here */
+        return (bitrate + 50000) / 100000;
+}
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 584eb4826e02..2fa8de1140e9 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -1256,10 +1256,7 @@ int cfg80211_wext_giwrate(struct net_device *dev,
         if (!(sinfo.filled & STATION_INFO_TX_BITRATE))
                 return -EOPNOTSUPP;
 
-        rate->value = 0;
-
-        if (!(sinfo.txrate.flags & RATE_INFO_FLAGS_MCS))
-                rate->value = 100000 * sinfo.txrate.legacy;
+        rate->value = 100000 * cfg80211_calculate_bitrate(&sinfo.txrate);
 
         return 0;
 }