drivers/net/wireless/libertas/tx.c

   1 /*
   2  * This file contains the handling of TX in wlan driver.
   3  */
   4 #include <linux/hardirq.h>
   5 #include <linux/netdevice.h>
   6 #include <linux/etherdevice.h>
   7 #include <linux/sched.h>
   8 #include <net/cfg80211.h>
   9
  10 #include "host.h"
  11 #include "radiotap.h"
  12 #include "decl.h"
  13 #include "defs.h"
  14 #include "dev.h"
  15
  16 /**
  17  * convert_radiotap_rate_to_mv - converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
  18  * units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
  19  *
  20  * @rate:       Input rate
  21  * returns:     Output Rate (0 if invalid)
  22  */
  23 static u32 convert_radiotap_rate_to_mv(u8 rate)
  24 {
  25         switch (rate) {
  26         case 2:         /*   1 Mbps */
  27                 return 0 | (1 << 4);
  28         case 4:         /*   2 Mbps */
  29                 return 1 | (1 << 4);
  30         case 11:                /* 5.5 Mbps */
  31                 return 2 | (1 << 4);
  32         case 22:                /*  11 Mbps */
  33                 return 3 | (1 << 4);
  34         case 12:                /*   6 Mbps */
  35                 return 4 | (1 << 4);
  36         case 18:                /*   9 Mbps */
  37                 return 5 | (1 << 4);
  38         case 24:                /*  12 Mbps */
  39                 return 6 | (1 << 4);
  40         case 36:                /*  18 Mbps */
  41                 return 7 | (1 << 4);
  42         case 48:                /*  24 Mbps */
  43                 return 8 | (1 << 4);
  44         case 72:                /*  36 Mbps */
  45                 return 9 | (1 << 4);
  46         case 96:                /*  48 Mbps */
  47                 return 10 | (1 << 4);
  48         case 108:               /*  54 Mbps */
  49                 return 11 | (1 << 4);
  50         }
  51         return 0;
  52 }
  53
  54 /**
  55  * lbs_hard_start_xmit - checks the conditions and sends packet to IF
  56  * layer if everything is ok
  57  *
  58  * @skb:        A pointer to skb which includes TX packet
  59  * @dev:        A pointer to the &struct net_device
  60  * returns:     0 or -1
  61  */
  62 netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
  63 {
  64         unsigned long flags;
  65         struct lbs_private *priv = dev->ml_priv;
  66         struct txpd *txpd;
  67         char *p802x_hdr;
  68         uint16_t pkt_len;
  69         netdev_tx_t ret = NETDEV_TX_OK;
  70
  71         lbs_deb_enter(LBS_DEB_TX);
  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                 dev->stats.tx_dropped++;
  86                 dev->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 (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 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         lbs_mesh_set_txpd(priv, dev, txpd);
 136
 137         lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
 138
 139         lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 140
 141         memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 142
 143         spin_lock_irqsave(&priv->driver_lock, flags);
 144         priv->tx_pending_len = pkt_len + sizeof(struct txpd);
 145
 146         lbs_deb_tx("%s lined up packet\n", __func__);
 147
 148         dev->stats.tx_packets++;
 149         dev->stats.tx_bytes += skb->len;
 150
 151         if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 152                 /* Keep the skb to echo it back once Tx feedback is
 153                    received from FW */
 154                 skb_orphan(skb);
 155
 156                 /* Keep the skb around for when we get feedback */
 157                 priv->currenttxskb = skb;
 158         } else {
 159  free:
 160                 dev_kfree_skb_any(skb);
 161         }
 162
 163  unlock:
 164         spin_unlock_irqrestore(&priv->driver_lock, flags);
 165         wake_up(&priv->waitq);
 166
 167         lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
 168         return ret;
 169 }
 170
 171 /**
 172  * lbs_send_tx_feedback - sends to the host the last transmitted packet,
 173  * filling the radiotap headers with transmission information.
 174  *
 175  * @priv:       A pointer to &struct lbs_private structure
 176  * @try_count:  A 32-bit value containing transmission retry status.
 177  *
 178  * returns:     void
 179  */
 180 void lbs_send_tx_feedback(struct lbs_private *priv, u32 try_count)
 181 {
 182         struct tx_radiotap_hdr *radiotap_hdr;
 183
 184         if (priv->wdev->iftype != NL80211_IFTYPE_MONITOR ||
 185             priv->currenttxskb == NULL)
 186                 return;
 187
 188         radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
 189
 190         radiotap_hdr->data_retries = try_count ?
 191                 (1 + priv->txretrycount - try_count) : 0;
 192
 193         priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
 194                                                       priv->dev);
 195         netif_rx(priv->currenttxskb);
 196
 197         priv->currenttxskb = NULL;
 198
 199         if (priv->connect_status == LBS_CONNECTED)
 200                 netif_wake_queue(priv->dev);
 201
 202         if (priv->mesh_dev && netif_running(priv->mesh_dev))
 203                 netif_wake_queue(priv->mesh_dev);
 204 }
 205 EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);