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	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 */
182void 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}
207EXPORT_SYMBOL_GPL(lbs_send_tx_feedback);
208