rt2x00: Implement HT protection for rt2800

Update the HT operation mode when mac80211 sends it to us and set
the different HT protection modes and rates accordingly. For now
only use CTS-to-self with OFDM 24M or CCK 11M when protection is
required.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c
index 19534f272d76266d1ede2c4294ef59b5e60232c4..4ecacea677acc6933d0bd90528f863dd9fcf10e4 100644 (file)
--- a/drivers/net/wireless/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/rt2x00/rt2800lib.c
@@ -1169,6 +1169,102 @@ void rt2800_config_intf(struct rt2x00_dev *rt2x00dev, struct rt2x00_intf *intf,
 }
 EXPORT_SYMBOL_GPL(rt2800_config_intf);
 
+static void rt2800_config_ht_opmode(struct rt2x00_dev *rt2x00dev,
+                                   struct rt2x00lib_erp *erp)
+{
+       bool any_sta_nongf = !!(erp->ht_opmode &
+                               IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT);
+       u8 protection = erp->ht_opmode & IEEE80211_HT_OP_MODE_PROTECTION;
+       u8 mm20_mode, mm40_mode, gf20_mode, gf40_mode;
+       u16 mm20_rate, mm40_rate, gf20_rate, gf40_rate;
+       u32 reg;
+
+       /* default protection rate for HT20: OFDM 24M */
+       mm20_rate = gf20_rate = 0x4004;
+
+       /* default protection rate for HT40: duplicate OFDM 24M */
+       mm40_rate = gf40_rate = 0x4084;
+
+       switch (protection) {
+       case IEEE80211_HT_OP_MODE_PROTECTION_NONE:
+               /*
+                * All STAs in this BSS are HT20/40 but there might be
+                * STAs not supporting greenfield mode.
+                * => Disable protection for HT transmissions.
+                */
+               mm20_mode = mm40_mode = gf20_mode = gf40_mode = 0;
+
+               break;
+       case IEEE80211_HT_OP_MODE_PROTECTION_20MHZ:
+               /*
+                * All STAs in this BSS are HT20 or HT20/40 but there
+                * might be STAs not supporting greenfield mode.
+                * => Protect all HT40 transmissions.
+                */
+               mm20_mode = gf20_mode = 0;
+               mm40_mode = gf40_mode = 2;
+
+               break;
+       case IEEE80211_HT_OP_MODE_PROTECTION_NONMEMBER:
+               /*
+                * Nonmember protection:
+                * According to 802.11n we _should_ protect all
+                * HT transmissions (but we don't have to).
+                *
+                * But if cts_protection is enabled we _shall_ protect
+                * all HT transmissions using a CCK rate.
+                *
+                * And if any station is non GF we _shall_ protect
+                * GF transmissions.
+                *
+                * We decide to protect everything
+                * -> fall through to mixed mode.
+                */
+       case IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED:
+               /*
+                * Legacy STAs are present
+                * => Protect all HT transmissions.
+                */
+               mm20_mode = mm40_mode = gf20_mode = gf40_mode = 2;
+
+               /*
+                * If erp protection is needed we have to protect HT
+                * transmissions with CCK 11M long preamble.
+                */
+               if (erp->cts_protection) {
+                       /* don't duplicate RTS/CTS in CCK mode */
+                       mm20_rate = mm40_rate = 0x0003;
+                       gf20_rate = gf40_rate = 0x0003;
+               }
+               break;
+       };
+
+       /* check for STAs not supporting greenfield mode */
+       if (any_sta_nongf)
+               gf20_mode = gf40_mode = 2;
+
+       /* Update HT protection config */
+       rt2800_register_read(rt2x00dev, MM20_PROT_CFG, &reg);
+       rt2x00_set_field32(&reg, MM20_PROT_CFG_PROTECT_RATE, mm20_rate);
+       rt2x00_set_field32(&reg, MM20_PROT_CFG_PROTECT_CTRL, mm20_mode);
+       rt2800_register_write(rt2x00dev, MM20_PROT_CFG, reg);
+
+       rt2800_register_read(rt2x00dev, MM40_PROT_CFG, &reg);
+       rt2x00_set_field32(&reg, MM40_PROT_CFG_PROTECT_RATE, mm40_rate);
+       rt2x00_set_field32(&reg, MM40_PROT_CFG_PROTECT_CTRL, mm40_mode);
+       rt2800_register_write(rt2x00dev, MM40_PROT_CFG, reg);
+
+       rt2800_register_read(rt2x00dev, GF20_PROT_CFG, &reg);
+       rt2x00_set_field32(&reg, GF20_PROT_CFG_PROTECT_RATE, gf20_rate);
+       rt2x00_set_field32(&reg, GF20_PROT_CFG_PROTECT_CTRL, gf20_mode);
+       rt2800_register_write(rt2x00dev, GF20_PROT_CFG, reg);
+
+       rt2800_register_read(rt2x00dev, GF40_PROT_CFG, &reg);
+       rt2x00_set_field32(&reg, GF40_PROT_CFG_PROTECT_RATE, gf40_rate);
+       rt2x00_set_field32(&reg, GF40_PROT_CFG_PROTECT_CTRL, gf40_mode);
+       rt2800_register_write(rt2x00dev, GF40_PROT_CFG, reg);
+}
+
 void rt2800_config_erp(struct rt2x00_dev *rt2x00dev, struct rt2x00lib_erp *erp,
                       u32 changed)
 {
@@ -1213,6 +1309,9 @@ void rt2800_config_erp(struct rt2x00_dev *rt2x00dev, struct rt2x00lib_erp *erp,
                                   erp->beacon_int * 16);
                rt2800_register_write(rt2x00dev, BCN_TIME_CFG, reg);
        }
+
+       if (changed & BSS_CHANGED_HT)
+               rt2800_config_ht_opmode(rt2x00dev, erp);
 }
 EXPORT_SYMBOL_GPL(rt2800_config_erp);
 

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index bab10adae5372227b5bfe00d7609fb1462f0ec45..75ac6624bf9e3914d9e571d03526cf5ea19cd4eb 100644 (file)
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -458,6 +458,7 @@ struct rt2x00lib_erp {
        short eifs;
 
        u16 beacon_int;
+       u16 ht_opmode;
 };
 
 /*

diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c
index 4c7ff765a8bf5f2ba80dbcd992d6d6327ad7de19..54ffb5aeb34e4b808f1a94bcf8e6de7463883893 100644 (file)
--- a/drivers/net/wireless/rt2x00/rt2x00config.c
+++ b/drivers/net/wireless/rt2x00/rt2x00config.c
@@ -103,6 +103,9 @@ void rt2x00lib_config_erp(struct rt2x00_dev *rt2x00dev,
        /* Update global beacon interval time, this is needed for PS support */
        rt2x00dev->beacon_int = bss_conf->beacon_int;
 
+       if (changed & BSS_CHANGED_HT)
+               erp.ht_opmode = bss_conf->ht_operation_mode;
+
        rt2x00dev->ops->lib->config_erp(rt2x00dev, &erp, changed);
 }
 

diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index 7862a840984a8a0229cdc1a4c716fd5f41bdc81d..c3c206a97d54c608da497256a7fcadd44293d9df 100644 (file)
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -671,7 +671,7 @@ void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
         */
        if (changes & (BSS_CHANGED_ERP_CTS_PROT | BSS_CHANGED_ERP_PREAMBLE |
                       BSS_CHANGED_ERP_SLOT | BSS_CHANGED_BASIC_RATES |
-                      BSS_CHANGED_BEACON_INT))
+                      BSS_CHANGED_BEACON_INT | BSS_CHANGED_HT))
                rt2x00lib_config_erp(rt2x00dev, intf, bss_conf, changes);
 }
 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);