summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/rt2x00/rt2x00ht.c
blob: c637bcaec5f8d6ef37320950f5bf9964f4bde675 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
/*
	Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
	<http://rt2x00.serialmonkey.com>

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the
	Free Software Foundation, Inc.,
	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
	Module: rt2x00lib
	Abstract: rt2x00 HT specific routines.
 */

#include <linux/kernel.h>
#include <linux/module.h>

#include "rt2x00.h"
#include "rt2x00lib.h"

void rt2x00ht_create_tx_descriptor(struct queue_entry *entry,
				   struct txentry_desc *txdesc,
				   const struct rt2x00_rate *hwrate)
{
	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
	struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;

	if (tx_info->control.sta)
		txdesc->mpdu_density =
		    tx_info->control.sta->ht_cap.ampdu_density;
	else
		txdesc->mpdu_density = 0;

	txdesc->ba_size = 7;	/* FIXME: What value is needed? */

	txdesc->stbc =
	    (tx_info->flags & IEEE80211_TX_CTL_STBC) >> IEEE80211_TX_CTL_STBC_SHIFT;

	/*
	 * If IEEE80211_TX_RC_MCS is set txrate->idx just contains the
	 * mcs rate to be used
	 */
	if (txrate->flags & IEEE80211_TX_RC_MCS) {
		txdesc->mcs = txrate->idx;

		/*
		 * MIMO PS should be set to 1 for STA's using dynamic SM PS
		 * when using more then one tx stream (>MCS7).
		 */
		if (tx_info->control.sta && txdesc->mcs > 7 &&
		    ((tx_info->control.sta->ht_cap.cap &
		      IEEE80211_HT_CAP_SM_PS) >>
		     IEEE80211_HT_CAP_SM_PS_SHIFT) ==
		    WLAN_HT_CAP_SM_PS_DYNAMIC)
			__set_bit(ENTRY_TXD_HT_MIMO_PS, &txdesc->flags);
	} else {
		txdesc->mcs = rt2x00_get_rate_mcs(hwrate->mcs);
		if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
			txdesc->mcs |= 0x08;
	}


	/*
	 * This frame is eligible for an AMPDU, however, don't aggregate
	 * frames that are intended to probe a specific tx rate.
	 */
	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU &&
	    !(tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE))
		__set_bit(ENTRY_TXD_HT_AMPDU, &txdesc->flags);

	/*
	 * Determine HT Mix/Greenfield rate mode
	 */
	if (txrate->flags & IEEE80211_TX_RC_MCS)
		txdesc->rate_mode = RATE_MODE_HT_MIX;
	if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD)
		txdesc->rate_mode = RATE_MODE_HT_GREENFIELD;

	/*
	 * Set 40Mhz mode if necessary (for legacy rates this will
	 * duplicate the frame to both channels).
	 */
	if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH ||
	    txrate->flags & IEEE80211_TX_RC_DUP_DATA)
		__set_bit(ENTRY_TXD_HT_BW_40, &txdesc->flags);
	if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
		__set_bit(ENTRY_TXD_HT_SHORT_GI, &txdesc->flags);

	/*
	 * Determine IFS values
	 * - Use TXOP_BACKOFF for management frames
	 * - Use TXOP_SIFS for fragment bursts
	 * - Use TXOP_HTTXOP for everything else
	 *
	 * Note: rt2800 devices won't use CTS protection (if used)
	 * for frames not transmitted with TXOP_HTTXOP
	 */
	if (ieee80211_is_mgmt(hdr->frame_control))
		txdesc->txop = TXOP_BACKOFF;
	else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
		txdesc->txop = TXOP_SIFS;
	else
		txdesc->txop = TXOP_HTTXOP;
}

u16 rt2x00ht_center_channel(struct rt2x00_dev *rt2x00dev,
			    struct ieee80211_conf *conf)
{
	struct hw_mode_spec *spec = &rt2x00dev->spec;
	int center_channel;
	u16 i;

	/*
	 * Initialize center channel to current channel.
	 */
	center_channel = spec->channels[conf->channel->hw_value].channel;

	/*
	 * Adjust center channel to HT40+ and HT40- operation.
	 */
	if (conf_is_ht40_plus(conf))
		center_channel += 2;
	else if (conf_is_ht40_minus(conf))
		center_channel -= (center_channel == 14) ? 1 : 2;

	for (i = 0; i < spec->num_channels; i++)
		if (spec->channels[i].channel == center_channel)
			return i;

	WARN_ON(1);
	return conf->channel->hw_value;
}