2 Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
3 <http://rt2x00.serialmonkey.com>
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.
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.
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.
23 Abstract: rt2x00 HT specific routines.
26 #include <linux/kernel.h>
27 #include <linux/module.h>
30 #include "rt2x00lib.h"
32 void rt2x00ht_create_tx_descriptor(struct queue_entry *entry,
33 struct txentry_desc *txdesc,
34 const struct rt2x00_rate *hwrate)
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;
40 if (tx_info->control.sta)
41 txdesc->u.ht.mpdu_density =
42 tx_info->control.sta->ht_cap.ampdu_density;
44 txdesc->u.ht.ba_size = 7; /* FIXME: What value is needed? */
47 * Only one STBC stream is supported for now.
49 if (tx_info->flags & IEEE80211_TX_CTL_STBC)
50 txdesc->u.ht.stbc = 1;
53 * If IEEE80211_TX_RC_MCS is set txrate->idx just contains the
56 if (txrate->flags & IEEE80211_TX_RC_MCS) {
57 txdesc->u.ht.mcs = txrate->idx;
60 * MIMO PS should be set to 1 for STA's using dynamic SM PS
61 * when using more then one tx stream (>MCS7).
63 if (tx_info->control.sta && txdesc->u.ht.mcs > 7 &&
64 ((tx_info->control.sta->ht_cap.cap &
65 IEEE80211_HT_CAP_SM_PS) >>
66 IEEE80211_HT_CAP_SM_PS_SHIFT) ==
67 WLAN_HT_CAP_SM_PS_DYNAMIC)
68 __set_bit(ENTRY_TXD_HT_MIMO_PS, &txdesc->flags);
70 txdesc->u.ht.mcs = rt2x00_get_rate_mcs(hwrate->mcs);
71 if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
72 txdesc->u.ht.mcs |= 0x08;
76 * This frame is eligible for an AMPDU, however, don't aggregate
77 * frames that are intended to probe a specific tx rate.
79 if (tx_info->flags & IEEE80211_TX_CTL_AMPDU &&
80 !(tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE))
81 __set_bit(ENTRY_TXD_HT_AMPDU, &txdesc->flags);
84 * Set 40Mhz mode if necessary (for legacy rates this will
85 * duplicate the frame to both channels).
87 if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH ||
88 txrate->flags & IEEE80211_TX_RC_DUP_DATA)
89 __set_bit(ENTRY_TXD_HT_BW_40, &txdesc->flags);
90 if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
91 __set_bit(ENTRY_TXD_HT_SHORT_GI, &txdesc->flags);
94 * Determine IFS values
95 * - Use TXOP_BACKOFF for management frames except beacons
96 * - Use TXOP_SIFS for fragment bursts
97 * - Use TXOP_HTTXOP for everything else
99 * Note: rt2800 devices won't use CTS protection (if used)
100 * for frames not transmitted with TXOP_HTTXOP
102 if (ieee80211_is_mgmt(hdr->frame_control) &&
103 !ieee80211_is_beacon(hdr->frame_control))
104 txdesc->u.ht.txop = TXOP_BACKOFF;
105 else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
106 txdesc->u.ht.txop = TXOP_SIFS;
108 txdesc->u.ht.txop = TXOP_HTTXOP;
111 u16 rt2x00ht_center_channel(struct rt2x00_dev *rt2x00dev,
112 struct ieee80211_conf *conf)
114 struct hw_mode_spec *spec = &rt2x00dev->spec;
119 * Initialize center channel to current channel.
121 center_channel = spec->channels[conf->channel->hw_value].channel;
124 * Adjust center channel to HT40+ and HT40- operation.
126 if (conf_is_ht40_plus(conf))
128 else if (conf_is_ht40_minus(conf))
129 center_channel -= (center_channel == 14) ? 1 : 2;
131 for (i = 0; i < spec->num_channels; i++)
132 if (spec->channels[i].channel == center_channel)
136 return conf->channel->hw_value;