rt2x00: Implement support for 802.11n

Extend rt2x00lib capabilities to support 802.11n,
it still lacks aggregation support, but that can
be added in the future.

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

1 files changed, 67 insertions, 25 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index e15086af7278..f2270845072a 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -323,19 +323,54 @@ void rt2x00lib_txdone(struct queue_entry *entry,
 }
 EXPORT_SYMBOL_GPL(rt2x00lib_txdone);
 
+static int rt2x00lib_rxdone_read_signal(struct rt2x00_dev *rt2x00dev,
+                                        struct rxdone_entry_desc *rxdesc)
+{
+        struct ieee80211_supported_band *sband;
+        const struct rt2x00_rate *rate;
+        unsigned int i;
+        int signal;
+        int type;
+
+        /*
+         * For non-HT rates the MCS value needs to contain the
+         * actually used rate modulation (CCK or OFDM).
+         */
+        if (rxdesc->dev_flags & RXDONE_SIGNAL_MCS)
+                signal = RATE_MCS(rxdesc->rate_mode, rxdesc->signal);
+        else
+                signal = rxdesc->signal;
+
+        type = (rxdesc->dev_flags & RXDONE_SIGNAL_MASK);
+
+        sband = &rt2x00dev->bands[rt2x00dev->curr_band];
+        for (i = 0; i < sband->n_bitrates; i++) {
+                rate = rt2x00_get_rate(sband->bitrates[i].hw_value);
+
+                if (((type == RXDONE_SIGNAL_PLCP) &&
+                     (rate->plcp == signal)) ||
+                    ((type == RXDONE_SIGNAL_BITRATE) &&
+                      (rate->bitrate == signal)) ||
+                    ((type == RXDONE_SIGNAL_MCS) &&
+                      (rate->mcs == signal))) {
+                        return i;
+                }
+        }
+
+        WARNING(rt2x00dev, "Frame received with unrecognized signal, "
+                "signal=0x%.4x, type=%d.\n", signal, type);
+        return 0;
+}
+
 void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev,
                       struct queue_entry *entry)
 {
         struct rxdone_entry_desc rxdesc;
         struct sk_buff *skb;
         struct ieee80211_rx_status *rx_status = &rt2x00dev->rx_status;
-        struct ieee80211_supported_band *sband;
-        const struct rt2x00_rate *rate;
         unsigned int header_length;
         bool l2pad;
-        unsigned int i;
-        int idx = -1;
-
+        int rate_idx;
         /*
          * Allocate a new sk_buffer. If no new buffer available, drop the
          * received frame and reuse the existing buffer.
@@ -379,26 +414,17 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev,
                 rt2x00queue_payload_align(entry->skb, l2pad, header_length);
 
         /*
-         * Update RX statistics.
+         * Check if the frame was received using HT. In that case,
+         * the rate is the MCS index and should be passed to mac80211
+         * directly. Otherwise we need to translate the signal to
+         * the correct bitrate index.
          */
-        sband = &rt2x00dev->bands[rt2x00dev->curr_band];
-        for (i = 0; i < sband->n_bitrates; i++) {
-                rate = rt2x00_get_rate(sband->bitrates[i].hw_value);
-
-                if (((rxdesc.dev_flags & RXDONE_SIGNAL_PLCP) &&
-                     (rate->plcp == rxdesc.signal)) ||
-                    ((rxdesc.dev_flags & RXDONE_SIGNAL_BITRATE) &&
-                      (rate->bitrate == rxdesc.signal))) {
-                        idx = i;
-                        break;
-                }
-        }
-
-        if (idx < 0) {
-                WARNING(rt2x00dev, "Frame received with unrecognized signal,"
-                        "signal=0x%.2x, type=%d.\n", rxdesc.signal,
-                        (rxdesc.dev_flags & RXDONE_SIGNAL_MASK));
-                idx = 0;
+        if (rxdesc.rate_mode == RATE_MODE_CCK ||
+            rxdesc.rate_mode == RATE_MODE_OFDM) {
+                rate_idx = rt2x00lib_rxdone_read_signal(rt2x00dev, &rxdesc);
+        } else {
+                rxdesc.flags |= RX_FLAG_HT;
+                rate_idx = rxdesc.signal;
         }
 
         /*
@@ -408,7 +434,7 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev,
         rt2x00debug_update_crypto(rt2x00dev, &rxdesc);
 
         rx_status->mactime = rxdesc.timestamp;
-        rx_status->rate_idx = idx;
+        rx_status->rate_idx = rate_idx;
         rx_status->qual = rt2x00link_calculate_signal(rt2x00dev, rxdesc.rssi);
         rx_status->signal = rxdesc.rssi;
         rx_status->noise = rxdesc.noise;
@@ -443,72 +469,84 @@ const struct rt2x00_rate rt2x00_supported_rates[12] = {
                 .bitrate = 10,
                 .ratemask = BIT(0),
                 .plcp = 0x00,
+                .mcs = RATE_MCS(RATE_MODE_CCK, 0),
         },
         {
                 .flags = DEV_RATE_CCK | DEV_RATE_SHORT_PREAMBLE,
                 .bitrate = 20,
                 .ratemask = BIT(1),
                 .plcp = 0x01,
+                .mcs = RATE_MCS(RATE_MODE_CCK, 1),
         },
         {
                 .flags = DEV_RATE_CCK | DEV_RATE_SHORT_PREAMBLE,
                 .bitrate = 55,
                 .ratemask = BIT(2),
                 .plcp = 0x02,
+                .mcs = RATE_MCS(RATE_MODE_CCK, 2),
         },
         {
                 .flags = DEV_RATE_CCK | DEV_RATE_SHORT_PREAMBLE,
                 .bitrate = 110,
                 .ratemask = BIT(3),
                 .plcp = 0x03,
+                .mcs = RATE_MCS(RATE_MODE_CCK, 3),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 60,
                 .ratemask = BIT(4),
                 .plcp = 0x0b,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 0),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 90,
                 .ratemask = BIT(5),
                 .plcp = 0x0f,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 1),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 120,
                 .ratemask = BIT(6),
                 .plcp = 0x0a,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 2),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 180,
                 .ratemask = BIT(7),
                 .plcp = 0x0e,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 3),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 240,
                 .ratemask = BIT(8),
                 .plcp = 0x09,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 4),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 360,
                 .ratemask = BIT(9),
                 .plcp = 0x0d,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 5),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 480,
                 .ratemask = BIT(10),
                 .plcp = 0x08,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 6),
         },
         {
                 .flags = DEV_RATE_OFDM,
                 .bitrate = 540,
                 .ratemask = BIT(11),
                 .plcp = 0x0c,
+                .mcs = RATE_MCS(RATE_MODE_OFDM, 7),
         },
 };
 
@@ -584,6 +622,8 @@ static int rt2x00lib_probe_hw_modes(struct rt2x00_dev *rt2x00dev,
                 rt2x00dev->bands[IEEE80211_BAND_2GHZ].bitrates = rates;
                 hw->wiphy->bands[IEEE80211_BAND_2GHZ] =
                     &rt2x00dev->bands[IEEE80211_BAND_2GHZ];
+                memcpy(&rt2x00dev->bands[IEEE80211_BAND_2GHZ].ht_cap,
+                       &spec->ht, sizeof(spec->ht));
         }
 
         /*
@@ -600,6 +640,8 @@ static int rt2x00lib_probe_hw_modes(struct rt2x00_dev *rt2x00dev,
                 rt2x00dev->bands[IEEE80211_BAND_5GHZ].bitrates = &rates[4];
                 hw->wiphy->bands[IEEE80211_BAND_5GHZ] =
                     &rt2x00dev->bands[IEEE80211_BAND_5GHZ];
+                memcpy(&rt2x00dev->bands[IEEE80211_BAND_5GHZ].ht_cap,
+                       &spec->ht, sizeof(spec->ht));
         }
 
         return 0;