diff options
| author | John W. Linville <linville@tuxdriver.com> | 2009-12-09 22:43:52 +0100 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2009-12-21 17:27:31 +0100 |
| commit | 254416aae70ab2e6b57fd79782c8a67196234d02 (patch) | |
| tree | e28d54d1514634b591b54296b35bb9029e7b5a9c /net/wireless/util.c | |
| parent | sctp: fix compile error due to sysctl mismerge (diff) | |
| download | linux-254416aae70ab2e6b57fd79782c8a67196234d02.tar.xz linux-254416aae70ab2e6b57fd79782c8a67196234d02.zip | |
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>
Diffstat (limited to 'net/wireless/util.c')
| -rw-r--r-- | net/wireless/util.c | 33 |
1 files changed, 33 insertions, 0 deletions
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; +} |