1/*
2 * Copyright 2007-2012 Siemens AG
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2
6 * as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * GNU General Public License for more details.
12 *
13 * Written by:
14 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
15 * Sergey Lapin <slapin@ossfans.org>
16 * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
17 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
18 */
19
20#include <linux/netdevice.h>
21#include <linux/if_arp.h>
22#include <linux/crc-ccitt.h>
23#include <asm/unaligned.h>
24
25#include <net/rtnetlink.h>
26#include <net/ieee802154_netdev.h>
27#include <net/mac802154.h>
28#include <net/cfg802154.h>
29
30#include "ieee802154_i.h"
31#include "driver-ops.h"
32
33void ieee802154_xmit_worker(struct work_struct *work)
34{
35	struct ieee802154_local *local =
36		container_of(work, struct ieee802154_local, tx_work);
37	struct sk_buff *skb = local->tx_skb;
38	struct net_device *dev = skb->dev;
39	int res;
40
41	rtnl_lock();
42
43	/* check if ifdown occurred while schedule */
44	if (!netif_running(dev))
45		goto err_tx;
46
47	res = drv_xmit_sync(local, skb);
48	if (res)
49		goto err_tx;
50
51	ieee802154_xmit_complete(&local->hw, skb, false);
52
53	dev->stats.tx_packets++;
54	dev->stats.tx_bytes += skb->len;
55
56	rtnl_unlock();
57
58	return;
59
60err_tx:
61	/* Restart the netif queue on each sub_if_data object. */
62	ieee802154_wake_queue(&local->hw);
63	rtnl_unlock();
64	kfree_skb(skb);
65	netdev_dbg(dev, "transmission failed\n");
66}
67
68static netdev_tx_t
69ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
70{
71	struct net_device *dev = skb->dev;
72	int ret;
73
74	if (!(local->hw.flags & IEEE802154_HW_TX_OMIT_CKSUM)) {
75		u16 crc = crc_ccitt(0, skb->data, skb->len);
76
77		put_unaligned_le16(crc, skb_put(skb, 2));
78	}
79
80	/* Stop the netif queue on each sub_if_data object. */
81	ieee802154_stop_queue(&local->hw);
82
83	/* async is priority, otherwise sync is fallback */
84	if (local->ops->xmit_async) {
85		ret = drv_xmit_async(local, skb);
86		if (ret) {
87			ieee802154_wake_queue(&local->hw);
88			goto err_tx;
89		}
90
91		dev->stats.tx_packets++;
92		dev->stats.tx_bytes += skb->len;
93	} else {
94		local->tx_skb = skb;
95		queue_work(local->workqueue, &local->tx_work);
96	}
97
98	return NETDEV_TX_OK;
99
100err_tx:
101	kfree_skb(skb);
102	return NETDEV_TX_OK;
103}
104
105netdev_tx_t
106ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev)
107{
108	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
109
110	skb->skb_iif = dev->ifindex;
111
112	return ieee802154_tx(sdata->local, skb);
113}
114
115netdev_tx_t
116ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev)
117{
118	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
119	int rc;
120
121	/* TODO we should move it to wpan_dev_hard_header and dev_hard_header
122	 * functions. The reason is wireshark will show a mac header which is
123	 * with security fields but the payload is not encrypted.
124	 */
125	rc = mac802154_llsec_encrypt(&sdata->sec, skb);
126	if (rc) {
127		netdev_warn(dev, "encryption failed: %i\n", rc);
128		kfree_skb(skb);
129		return NETDEV_TX_OK;
130	}
131
132	skb->skb_iif = dev->ifindex;
133
134	return ieee802154_tx(sdata->local, skb);
135}
136