diff options
Diffstat (limited to 'net/mac80211/util.c')
| -rw-r--r-- | net/mac80211/util.c | 39 |
1 files changed, 26 insertions, 13 deletions
diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 22654452a56..61856e17a1e 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -107,7 +107,8 @@ void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx) } int ieee80211_frame_duration(enum ieee80211_band band, size_t len, - int rate, int erp, int short_preamble) + int rate, int erp, int short_preamble, + int shift) { int dur; @@ -118,6 +119,9 @@ int ieee80211_frame_duration(enum ieee80211_band band, size_t len, * * rate is in 100 kbps, so divident is multiplied by 10 in the * DIV_ROUND_UP() operations. + * + * shift may be 2 for 5 MHz channels or 1 for 10 MHz channels, and + * is assumed to be 0 otherwise. */ if (band == IEEE80211_BAND_5GHZ || erp) { @@ -130,15 +134,21 @@ int ieee80211_frame_duration(enum ieee80211_band band, size_t len, * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext * * T_SYM = 4 usec - * 802.11a - 17.5.2: aSIFSTime = 16 usec + * 802.11a - 18.5.2: aSIFSTime = 16 usec * 802.11g - 19.8.4: aSIFSTime = 10 usec + * signal ext = 6 usec */ dur = 16; /* SIFS + signal ext */ - dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */ - dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */ + dur += 16; /* IEEE 802.11-2012 18.3.2.4: T_PREAMBLE = 16 usec */ + dur += 4; /* IEEE 802.11-2012 18.3.2.4: T_SIGNAL = 4 usec */ dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10, 4 * rate); /* T_SYM x N_SYM */ + + /* IEEE 802.11-2012 18.3.2.4: all values above are: + * * times 4 for 5 MHz + * * times 2 for 10 MHz + */ + dur *= 1 << shift; } else { /* * 802.11b or 802.11g with 802.11b compatibility: @@ -168,7 +178,7 @@ __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, { struct ieee80211_sub_if_data *sdata; u16 dur; - int erp; + int erp, shift = 0; bool short_preamble = false; erp = 0; @@ -177,10 +187,11 @@ __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, short_preamble = sdata->vif.bss_conf.use_short_preamble; if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = rate->flags & IEEE80211_RATE_ERP_G; + shift = ieee80211_vif_get_shift(vif); } dur = ieee80211_frame_duration(band, frame_len, rate->bitrate, erp, - short_preamble); + short_preamble, shift); return cpu_to_le16(dur); } @@ -194,7 +205,7 @@ __le16 ieee80211_rts_duration(struct ieee80211_hw *hw, struct ieee80211_rate *rate; struct ieee80211_sub_if_data *sdata; bool short_preamble; - int erp; + int erp, shift = 0; u16 dur; struct ieee80211_supported_band *sband; @@ -210,17 +221,18 @@ __le16 ieee80211_rts_duration(struct ieee80211_hw *hw, short_preamble = sdata->vif.bss_conf.use_short_preamble; if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = rate->flags & IEEE80211_RATE_ERP_G; + shift = ieee80211_vif_get_shift(vif); } /* CTS duration */ dur = ieee80211_frame_duration(sband->band, 10, rate->bitrate, - erp, short_preamble); + erp, short_preamble, shift); /* Data frame duration */ dur += ieee80211_frame_duration(sband->band, frame_len, rate->bitrate, - erp, short_preamble); + erp, short_preamble, shift); /* ACK duration */ dur += ieee80211_frame_duration(sband->band, 10, rate->bitrate, - erp, short_preamble); + erp, short_preamble, shift); return cpu_to_le16(dur); } @@ -235,7 +247,7 @@ __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, struct ieee80211_rate *rate; struct ieee80211_sub_if_data *sdata; bool short_preamble; - int erp; + int erp, shift = 0; u16 dur; struct ieee80211_supported_band *sband; @@ -250,15 +262,16 @@ __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, short_preamble = sdata->vif.bss_conf.use_short_preamble; if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = rate->flags & IEEE80211_RATE_ERP_G; + shift = ieee80211_vif_get_shift(vif); } /* Data frame duration */ dur = ieee80211_frame_duration(sband->band, frame_len, rate->bitrate, - erp, short_preamble); + erp, short_preamble, shift); if (!(frame_txctl->flags & IEEE80211_TX_CTL_NO_ACK)) { /* ACK duration */ dur += ieee80211_frame_duration(sband->band, 10, rate->bitrate, - erp, short_preamble); + erp, short_preamble, shift); } return cpu_to_le16(dur); |