drivers/net/wireless/libertas/tx.c

   1 /**
   2   * This file contains the handling of TX in wlan driver.
   3   */
   4 #include <linux/netdevice.h>
   5 #include <linux/etherdevice.h>
   6 #include <linux/sched.h>
   7 #include <net/cfg80211.h>
   8
   9 #include "host.h"
  10 #include "radiotap.h"
  11 #include "decl.h"
  12 #include "defs.h"
  13 #include "dev.h"
  14
  15 /**
  16  *  @brief This function converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
  17  *  units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
  18  *
  19  *  @param rate    Input rate
  20  *  @return      Output Rate (0 if invalid)
  21  */
  22 static u32 convert_radiotap_rate_to_mv(u8 rate)
  23 {
  24         switch (rate) {
  25         case 2:         /*   1 Mbps */
  26                 return 0 | (1 << 4);
  27         case 4:         /*   2 Mbps */
  28                 return 1 | (1 << 4);
  29         case 11:                /* 5.5 Mbps */
  30                 return 2 | (1 << 4);
  31         case 22:                /*  11 Mbps */
  32                 return 3 | (1 << 4);
  33         case 12:                /*   6 Mbps */
  34                 return 4 | (1 << 4);
  35         case 18:                /*   9 Mbps */
  36                 return 5 | (1 << 4);
  37         case 24:                /*  12 Mbps */
  38                 return 6 | (1 << 4);
  39         case 36:                /*  18 Mbps */
  40                 return 7 | (1 << 4);
  41         case 48:                /*  24 Mbps */
  42                 return 8 | (1 << 4);
  43         case 72:                /*  36 Mbps */
  44                 return 9 | (1 << 4);
  45         case 96:                /*  48 Mbps */
  46                 return 10 | (1 << 4);
  47         case 108:               /*  54 Mbps */
  48                 return 11 | (1 << 4);
  49         }
  50         return 0;
  51 }
  52
  53 /**
  54  *  @brief This function checks the conditions and sends packet to IF
  55  *  layer if everything is ok.
  56  *
  57  *  @param priv    A pointer to struct lbs_private structure
  58  *  @param skb     A pointer to skb which includes TX packet
  59  *  @return        0 or -1
  60  */
  61 netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
  62 {
  63         unsigned long flags;
  64         struct lbs_private *priv = dev->ml_priv;
  65         struct txpd *txpd;
  66         char *p802x_hdr;
  67         uint16_t pkt_len;
  68         netdev_tx_t ret = NETDEV_TX_OK;
  69
  70         lbs_deb_enter(LBS_DEB_TX);
  71
  72         /* We need to protect against the queues being restarted before
  73            we get round to stopping them */
  74         spin_lock_irqsave(&priv->driver_lock, flags);
  75
  76         if (priv->surpriseremoved)
  77                 goto free;
  78
  79         if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
  80                 lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
  81                        skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
  82                 /* We'll never manage to send this one; drop it and return 'OK' */
  83
  84                 dev->stats.tx_dropped++;
  85                 dev->stats.tx_errors++;
  86                 goto free;
  87         }
  88
  89
  90         netif_stop_queue(priv->dev);
  91         if (priv->mesh_dev)
  92                 netif_stop_queue(priv->mesh_dev);
  93
  94         if (priv->tx_pending_len) {
  95                 /* This can happen if packets come in on the mesh and eth
  96                    device simultaneously -- there's no mutual exclusion on
  97                    hard_start_xmit() calls between devices. */
  98                 lbs_deb_tx("Packet on %s while busy\n", dev->name);
  99                 ret = NETDEV_TX_BUSY;
 100                 goto unlock;
 101         }
 102
 103         priv->tx_pending_len = -1;
 104         spin_unlock_irqrestore(&priv->driver_lock, flags);
 105
 106         lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
 107
 108         txpd = (void *)priv->tx_pending_buf;
 109         memset(txpd, 0, sizeof(struct txpd));
 110
 111         p802x_hdr = skb->data;
 112         pkt_len = skb->len;
 113
 114         if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 115                 struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
 116
 117                 /* set txpd fields from the radiotap header */
 118                 txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
 119
 120                 /* skip the radiotap header */
 121                 p802x_hdr += sizeof(*rtap_hdr);
 122                 pkt_len -= sizeof(*rtap_hdr);
 123
 124                 /* copy destination address from 802.11 header */
 125                 memcpy(txpd->tx_dest_addr_high, p802x_hdr + 4, ETH_ALEN);
 126         } else {
 127                 /* copy destination address from 802.3 header */
 128                 memcpy(txpd->tx_dest_addr_high, p802x_hdr, ETH_ALEN);
 129         }
 130
 131         txpd->tx_packet_length = cpu_to_le16(pkt_len);
 132         txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
 133
 134         lbs_mesh_set_txpd(priv, dev, txpd);
 135
 136         lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
 137
 138         lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 139
 140         memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 141
 142         spin_lock_irqsave(&priv->driver_lock, flags);
 143         priv->tx_pending_len = pkt_len + sizeof(struct txpd);
 144
 145         lbs_deb_tx("%s lined up packet\n", __func__);
 146
 147         dev->stats.tx_packets++;
 148         dev->stats.tx_bytes += skb->len;
 149
 150         if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 151                 /* Keep the skb to echo it back once Tx feedback is
 152                    received from FW */
 153                 skb_orphan(skb);
 154
 155                 /* Keep the skb around for when we get feedback */
 156                 priv->currenttxskb = skb;
 157         } else {
 158  free:
 159                 dev_kfree_skb_any(skb);
 160         }
 161
 162  unlock:
 163         spin_unlock_irqrestore(&priv->driver_lock, flags);
 164         wake_up(&priv->waitq);
 165
 166         lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
 167         return ret;
 168 }
 169
 170 /**
 171  *  @brief This function sends to the host the last transmitted packet,
 172  *  filling the radiotap headers with transmission information.
 173  *
 174  *  @param priv     A pointer to struct lbs_private structure
 175  *  @param status   A 32 bit value containing transmission status.
 176  *
 177  *  @returns void
 178  */
 179 void lbs_send_tx_feedback(struct lbs_private *priv, u32 try_count)
 180 {
 181         struct tx_radiotap_hdr *radiotap_hdr;
 182
 183         if (priv->wdev->iftype != NL80211_IFTYPE_MONITOR ||
 184             priv->currenttxskb == NULL)
 185                 return;
 186
 187         radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
 188
 189         radiotap_hdr->data_retries = try_count ?
 190                 (1 + priv->txretrycount - try_count) : 0;
 191
 192         priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
 193                                                       priv->dev);
 194         netif_rx(priv->currenttxskb);
 195
 196         priv->currenttxskb = NULL;
 197
 198         if (priv->connect_status == LBS_CONNECTED)
 199                 netif_wake_queue(priv->dev);
 200
 201         if (priv->mesh_dev && lbs_mesh_connected(priv))
 202                 netif_wake_queue(priv->mesh_dev);
 203 }
 204 EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);