1/* 2 Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com> 3 <http://rt2x00.serialmonkey.com> 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 2 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, write to the 17 Free Software Foundation, Inc., 18 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 */ 20 21/* 22 Module: rt2x00lib 23 Abstract: rt2x00 HT specific routines. 24 */ 25 26#include <linux/kernel.h> 27#include <linux/module.h> 28 29#include "rt2x00.h" 30#include "rt2x00lib.h" 31 32void rt2x00ht_create_tx_descriptor(struct queue_entry *entry, 33 struct txentry_desc *txdesc, 34 const struct rt2x00_rate *hwrate) 35{ 36 struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb); 37 struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0]; 38 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data; 39 40 if (tx_info->control.sta) 41 txdesc->mpdu_density = 42 tx_info->control.sta->ht_cap.ampdu_density; 43 else 44 txdesc->mpdu_density = 0; 45 46 txdesc->ba_size = 7; 47 48 txdesc->stbc = 49 (tx_info->flags & IEEE80211_TX_CTL_STBC) >> IEEE80211_TX_CTL_STBC_SHIFT; 50 51 /* 52 * If IEEE80211_TX_RC_MCS is set txrate->idx just contains the 53 * mcs rate to be used 54 */ 55 if (txrate->flags & IEEE80211_TX_RC_MCS) { 56 txdesc->mcs = txrate->idx; 57 } else { 58 txdesc->mcs = rt2x00_get_rate_mcs(hwrate->mcs); 59 if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE) 60 txdesc->mcs |= 0x08; 61 } 62 63 64 /* 65 * Convert flags 66 */ 67 if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) 68 __set_bit(ENTRY_TXD_HT_AMPDU, &txdesc->flags); 69 70 /* 71 * Determine HT Mix/Greenfield rate mode 72 */ 73 if (txrate->flags & IEEE80211_TX_RC_MCS) 74 txdesc->rate_mode = RATE_MODE_HT_MIX; 75 if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD) 76 txdesc->rate_mode = RATE_MODE_HT_GREENFIELD; 77 if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) 78 __set_bit(ENTRY_TXD_HT_BW_40, &txdesc->flags); 79 if (txrate->flags & IEEE80211_TX_RC_SHORT_GI) 80 __set_bit(ENTRY_TXD_HT_SHORT_GI, &txdesc->flags); 81 82 /* 83 * Determine IFS values 84 * - Use TXOP_BACKOFF for management frames 85 * - Use TXOP_SIFS for fragment bursts 86 * - Use TXOP_HTTXOP for everything else 87 * 88 * Note: rt2800 devices won't use CTS protection (if used) 89 * for frames not transmitted with TXOP_HTTXOP 90 */ 91 if (ieee80211_is_mgmt(hdr->frame_control)) 92 txdesc->txop = TXOP_BACKOFF; 93 else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)) 94 txdesc->txop = TXOP_SIFS; 95 else 96 txdesc->txop = TXOP_HTTXOP; 97} 98 99u16 rt2x00ht_center_channel(struct rt2x00_dev *rt2x00dev, 100 struct ieee80211_conf *conf) 101{ 102 struct hw_mode_spec *spec = &rt2x00dev->spec; 103 int center_channel; 104 u16 i; 105 106 /* 107 * Initialize center channel to current channel. 108 */ 109 center_channel = spec->channels[conf->channel->hw_value].channel; 110 111 /* 112 * Adjust center channel to HT40+ and HT40- operation. 113 */ 114 if (conf_is_ht40_plus(conf)) 115 center_channel += 2; 116 else if (conf_is_ht40_minus(conf)) 117 center_channel -= (center_channel == 14) ? 1 : 2; 118 119 for (i = 0; i < spec->num_channels; i++) 120 if (spec->channels[i].channel == center_channel) 121 return i; 122 123 WARN_ON(1); 124 return conf->channel->hw_value; 125} 126