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
   7 #include "hostcmd.h"
   8 #include "radiotap.h"
   9 #include "decl.h"
  10 #include "defs.h"
  11 #include "dev.h"
  12 #include "wext.h"
  13
  14 /**
  15  *  @brief This function converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
  16  *  units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
  17  *
  18  *  @param rate    Input rate
  19  *  @return      Output Rate (0 if invalid)
  20  */
  21 static u32 convert_radiotap_rate_to_mv(u8 rate)
  22 {
  23         switch (rate) {
  24         case 2:         /*   1 Mbps */
  25                 return 0 | (1 << 4);
  26         case 4:         /*   2 Mbps */
  27                 return 1 | (1 << 4);
  28         case 11:                /* 5.5 Mbps */
  29                 return 2 | (1 << 4);
  30         case 22:                /*  11 Mbps */
  31                 return 3 | (1 << 4);
  32         case 12:                /*   6 Mbps */
  33                 return 4 | (1 << 4);
  34         case 18:                /*   9 Mbps */
  35                 return 5 | (1 << 4);
  36         case 24:                /*  12 Mbps */
  37                 return 6 | (1 << 4);
  38         case 36:                /*  18 Mbps */
  39                 return 7 | (1 << 4);
  40         case 48:                /*  24 Mbps */
  41                 return 8 | (1 << 4);
  42         case 72:                /*  36 Mbps */
  43                 return 9 | (1 << 4);
  44         case 96:                /*  48 Mbps */
  45                 return 10 | (1 << 4);
  46         case 108:               /*  54 Mbps */
  47                 return 11 | (1 << 4);
  48         }
  49         return 0;
  50 }
  51
  52 /**
  53  *  @brief This function checks the conditions and sends packet to IF
  54  *  layer if everything is ok.
  55  *
  56  *  @param priv    A pointer to struct lbs_private structure
  57  *  @param skb     A pointer to skb which includes TX packet
  58  *  @return        0 or -1
  59  */
  60 int lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
  61 {
  62         unsigned long flags;
  63         struct lbs_private *priv = dev->priv;
  64         struct txpd *txpd;
  65         char *p802x_hdr;
  66         uint16_t pkt_len;
  67         int ret;
  68
  69         lbs_deb_enter(LBS_DEB_TX);
  70
  71         ret = NETDEV_TX_OK;
  72
  73         /* We need to protect against the queues being restarted before
  74            we get round to stopping them */
  75         spin_lock_irqsave(&priv->driver_lock, flags);
  76
  77         if (priv->surpriseremoved)
  78                 goto free;
  79
  80         if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
  81                 lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
  82                        skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
  83                 /* We'll never manage to send this one; drop it and return 'OK' */
  84
  85                 priv->stats.tx_dropped++;
  86                 priv->stats.tx_errors++;
  87                 goto free;
  88         }
  89
  90
  91         netif_stop_queue(priv->dev);
  92         if (priv->mesh_dev)
  93                 netif_stop_queue(priv->mesh_dev);
  94
  95         if (priv->tx_pending_len) {
  96                 /* This can happen if packets come in on the mesh and eth
  97                    device simultaneously -- there's no mutual exclusion on
  98                    hard_start_xmit() calls between devices. */
  99                 lbs_deb_tx("Packet on %s while busy\n", dev->name);
 100                 ret = NETDEV_TX_BUSY;
 101                 goto unlock;
 102         }
 103
 104         priv->tx_pending_len = -1;
 105         spin_unlock_irqrestore(&priv->driver_lock, flags);
 106
 107         lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
 108
 109         txpd = (void *)priv->tx_pending_buf;
 110         memset(txpd, 0, sizeof(struct txpd));
 111
 112         p802x_hdr = skb->data;
 113         pkt_len = skb->len;
 114
 115         if (dev == priv->rtap_net_dev) {
 116                 struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
 117
 118                 /* set txpd fields from the radiotap header */
 119                 txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
 120
 121                 /* skip the radiotap header */
 122                 p802x_hdr += sizeof(*rtap_hdr);
 123                 pkt_len -= sizeof(*rtap_hdr);
 124
 125                 /* copy destination address from 802.11 header */
 126                 memcpy(txpd->tx_dest_addr_high, p802x_hdr + 4, ETH_ALEN);
 127         } else {
 128                 /* copy destination address from 802.3 header */
 129                 memcpy(txpd->tx_dest_addr_high, p802x_hdr, ETH_ALEN);
 130         }
 131
 132         txpd->tx_packet_length = cpu_to_le16(pkt_len);
 133         txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
 134
 135         if (dev == priv->mesh_dev)
 136                 txpd->tx_control |= cpu_to_le32(TxPD_MESH_FRAME);
 137
 138         lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
 139
 140         lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 141
 142         memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 143
 144         spin_lock_irqsave(&priv->driver_lock, flags);
 145         priv->tx_pending_len = pkt_len + sizeof(struct txpd);
 146
 147         lbs_deb_tx("%s lined up packet\n", __func__);
 148
 149         priv->stats.tx_packets++;
 150         priv->stats.tx_bytes += skb->len;
 151
 152         dev->trans_start = jiffies;
 153
 154         if (priv->monitormode != LBS_MONITOR_OFF) {
 155                 /* Keep the skb to echo it back once Tx feedback is
 156                    received from FW */
 157                 skb_orphan(skb);
 158
 159                 /* Keep the skb around for when we get feedback */
 160                 priv->currenttxskb = skb;
 161         } else {
 162  free:
 163                 dev_kfree_skb_any(skb);
 164         }
 165  unlock:
 166         spin_unlock_irqrestore(&priv->driver_lock, flags);
 167         wake_up(&priv->waitq);
 168
 169         lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
 170         return ret;
 171 }
 172
 173 /**
 174  *  @brief This function sends to the host the last transmitted packet,
 175  *  filling the radiotap headers with transmission information.
 176  *
 177  *  @param priv     A pointer to struct lbs_private structure
 178  *  @param status   A 32 bit value containing transmission status.
 179  *
 180  *  @returns void
 181  */
 182 void lbs_send_tx_feedback(struct lbs_private *priv)
 183 {
 184         struct tx_radiotap_hdr *radiotap_hdr;
 185         u32 status = priv->eventcause;
 186         int txfail;
 187         int try_count;
 188
 189         if (priv->monitormode == LBS_MONITOR_OFF ||
 190             priv->currenttxskb == NULL)
 191                 return;
 192
 193         radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
 194
 195         txfail = (status >> 24);
 196
 197 #if 0
 198         /* The version of roofnet that we've tested does not use this yet
 199          * But it may be used in the future.
 200          */
 201         if (txfail)
 202                 radiotap_hdr->flags &= IEEE80211_RADIOTAP_F_TX_FAIL;
 203 #endif
 204         try_count = (status >> 16) & 0xff;
 205         radiotap_hdr->data_retries = (try_count) ?
 206             (1 + priv->txretrycount - try_count) : 0;
 207
 208
 209         priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
 210                                                       priv->rtap_net_dev);
 211         netif_rx(priv->currenttxskb);
 212
 213         priv->currenttxskb = NULL;
 214
 215         if (priv->connect_status == LBS_CONNECTED)
 216                 netif_wake_queue(priv->dev);
 217
 218         if (priv->mesh_dev && (priv->mesh_connect_status == LBS_CONNECTED))
 219                 netif_wake_queue(priv->mesh_dev);
 220 }
 221 EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);