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 <linux/export.h>
   9 #include <net/cfg80211.h>
  10
  11 #include "host.h"
  12 #include "radiotap.h"
  13 #include "decl.h"
  14 #include "defs.h"
  15 #include "dev.h"
  16 #include "mesh.h"
  17
  18 /**
  19  * convert_radiotap_rate_to_mv - converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
  20  * units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
  21  *
  22  * @rate:       Input rate
  23  * returns:     Output Rate (0 if invalid)
  24  */
  25 static u32 convert_radiotap_rate_to_mv(u8 rate)
  26 {
  27         switch (rate) {
  28         case 2:         /*   1 Mbps */
  29                 return 0 | (1 << 4);
  30         case 4:         /*   2 Mbps */
  31                 return 1 | (1 << 4);
  32         case 11:                /* 5.5 Mbps */
  33                 return 2 | (1 << 4);
  34         case 22:                /*  11 Mbps */
  35                 return 3 | (1 << 4);
  36         case 12:                /*   6 Mbps */
  37                 return 4 | (1 << 4);
  38         case 18:                /*   9 Mbps */
  39                 return 5 | (1 << 4);
  40         case 24:                /*  12 Mbps */
  41                 return 6 | (1 << 4);
  42         case 36:                /*  18 Mbps */
  43                 return 7 | (1 << 4);
  44         case 48:                /*  24 Mbps */
  45                 return 8 | (1 << 4);
  46         case 72:                /*  36 Mbps */
  47                 return 9 | (1 << 4);
  48         case 96:                /*  48 Mbps */
  49                 return 10 | (1 << 4);
  50         case 108:               /*  54 Mbps */
  51                 return 11 | (1 << 4);
  52         }
  53         return 0;
  54 }
  55
  56 /**
  57  * lbs_hard_start_xmit - checks the conditions and sends packet to IF
  58  * layer if everything is ok
  59  *
  60  * @skb:        A pointer to skb which includes TX packet
  61  * @dev:        A pointer to the &struct net_device
  62  * returns:     0 or -1
  63  */
  64 netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
  65 {
  66         unsigned long flags;
  67         struct lbs_private *priv = dev->ml_priv;
  68         struct txpd *txpd;
  69         char *p802x_hdr;
  70         uint16_t pkt_len;
  71         netdev_tx_t ret = NETDEV_TX_OK;
  72
  73         lbs_deb_enter(LBS_DEB_TX);
  74
  75         /* We need to protect against the queues being restarted before
  76            we get round to stopping them */
  77         spin_lock_irqsave(&priv->driver_lock, flags);
  78
  79         if (priv->surpriseremoved)
  80                 goto free;
  81
  82         if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
  83                 lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
  84                        skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
  85                 /* We'll never manage to send this one; drop it and return 'OK' */
  86
  87                 dev->stats.tx_dropped++;
  88                 dev->stats.tx_errors++;
  89                 goto free;
  90         }
  91
  92
  93         netif_stop_queue(priv->dev);
  94         if (priv->mesh_dev)
  95                 netif_stop_queue(priv->mesh_dev);
  96
  97         if (priv->tx_pending_len) {
  98                 /* This can happen if packets come in on the mesh and eth
  99                    device simultaneously -- there's no mutual exclusion on
 100                    hard_start_xmit() calls between devices. */
 101                 lbs_deb_tx("Packet on %s while busy\n", dev->name);
 102                 ret = NETDEV_TX_BUSY;
 103                 goto unlock;
 104         }
 105
 106         priv->tx_pending_len = -1;
 107         spin_unlock_irqrestore(&priv->driver_lock, flags);
 108
 109         lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
 110
 111         txpd = (void *)priv->tx_pending_buf;
 112         memset(txpd, 0, sizeof(struct txpd));
 113
 114         p802x_hdr = skb->data;
 115         pkt_len = skb->len;
 116
 117         if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 118                 struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
 119
 120                 /* set txpd fields from the radiotap header */
 121                 txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
 122
 123                 /* skip the radiotap header */
 124                 p802x_hdr += sizeof(*rtap_hdr);
 125                 pkt_len -= sizeof(*rtap_hdr);
 126
 127                 /* copy destination address from 802.11 header */
 128                 memcpy(txpd->tx_dest_addr_high, p802x_hdr + 4, ETH_ALEN);
 129         } else {
 130                 /* copy destination address from 802.3 header */
 131                 memcpy(txpd->tx_dest_addr_high, p802x_hdr, ETH_ALEN);
 132         }
 133
 134         txpd->tx_packet_length = cpu_to_le16(pkt_len);
 135         txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
 136
 137         lbs_mesh_set_txpd(priv, dev, txpd);
 138
 139         lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
 140
 141         lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 142
 143         memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
 144
 145         spin_lock_irqsave(&priv->driver_lock, flags);
 146         priv->tx_pending_len = pkt_len + sizeof(struct txpd);
 147
 148         lbs_deb_tx("%s lined up packet\n", __func__);
 149
 150         dev->stats.tx_packets++;
 151         dev->stats.tx_bytes += skb->len;
 152
 153         if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 154                 /* Keep the skb to echo it back once Tx feedback is
 155                    received from FW */
 156                 skb_orphan(skb);
 157
 158                 /* Keep the skb around for when we get feedback */
 159                 priv->currenttxskb = skb;
 160         } else {
 161  free:
 162                 dev_kfree_skb_any(skb);
 163         }
 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  * lbs_send_tx_feedback - sends to the host the last transmitted packet,
 175  * filling the radiotap headers with transmission information.
 176  *
 177  * @priv:       A pointer to &struct lbs_private structure
 178  * @try_count:  A 32-bit value containing transmission retry status.
 179  *
 180  * returns:     void
 181  */
 182 void lbs_send_tx_feedback(struct lbs_private *priv, u32 try_count)
 183 {
 184         struct tx_radiotap_hdr *radiotap_hdr;
 185
 186         if (priv->wdev->iftype != NL80211_IFTYPE_MONITOR ||
 187             priv->currenttxskb == NULL)
 188                 return;
 189
 190         radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
 191
 192         radiotap_hdr->data_retries = try_count ?
 193                 (1 + priv->txretrycount - try_count) : 0;
 194
 195         priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
 196                                                       priv->dev);
 197         netif_rx(priv->currenttxskb);
 198
 199         priv->currenttxskb = NULL;
 200
 201         if (priv->connect_status == LBS_CONNECTED)
 202                 netif_wake_queue(priv->dev);
 203
 204         if (priv->mesh_dev && netif_running(priv->mesh_dev))
 205                 netif_wake_queue(priv->mesh_dev);
 206 }
 207 EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);