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 */
 25static 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 */
 64netdev_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	/* 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	return ret;
168}
169
170/**
171 * lbs_send_tx_feedback - sends to the host the last transmitted packet,
172 * filling the radiotap headers with transmission information.
173 *
174 * @priv:	A pointer to &struct lbs_private structure
175 * @try_count:	A 32-bit value containing transmission retry status.
176 *
177 * returns:	void
178 */
179void 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 && netif_running(priv->mesh_dev))
202		netif_wake_queue(priv->mesh_dev);
203}
204EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);