Blame view

kernel/linux-imx6_3.14.28/net/mac802154/tx.c 3.32 KB
6b13f685e   김민수   BSP 최초 추가
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
  /*
   * Copyright 2007-2012 Siemens AG
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2
   * as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License along
   * with this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Written by:
   * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
   * Sergey Lapin <slapin@ossfans.org>
   * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
   * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
   */
  
  #include <linux/netdevice.h>
  #include <linux/if_arp.h>
  #include <linux/crc-ccitt.h>
  
  #include <net/ieee802154_netdev.h>
  #include <net/mac802154.h>
  #include <net/wpan-phy.h>
  
  #include "mac802154.h"
  
  /* IEEE 802.15.4 transceivers can sleep during the xmit session, so process
   * packets through the workqueue.
   */
  struct xmit_work {
  	struct sk_buff *skb;
  	struct work_struct work;
  	struct mac802154_priv *priv;
  	u8 chan;
  	u8 page;
  };
  
  static void mac802154_xmit_worker(struct work_struct *work)
  {
  	struct xmit_work *xw = container_of(work, struct xmit_work, work);
  	struct mac802154_sub_if_data *sdata;
  	int res;
  
  	mutex_lock(&xw->priv->phy->pib_lock);
  	if (xw->priv->phy->current_channel != xw->chan ||
  	    xw->priv->phy->current_page != xw->page) {
  		res = xw->priv->ops->set_channel(&xw->priv->hw,
  						  xw->page,
  						  xw->chan);
  		if (res) {
  			pr_debug("set_channel failed
  ");
  			goto out;
  		}
  
  		xw->priv->phy->current_channel = xw->chan;
  		xw->priv->phy->current_page = xw->page;
  	}
  
  	res = xw->priv->ops->xmit(&xw->priv->hw, xw->skb);
  	if (res)
  		pr_debug("transmission failed
  ");
  
  out:
  	mutex_unlock(&xw->priv->phy->pib_lock);
  
  	/* Restart the netif queue on each sub_if_data object. */
  	rcu_read_lock();
  	list_for_each_entry_rcu(sdata, &xw->priv->slaves, list)
  		netif_wake_queue(sdata->dev);
  	rcu_read_unlock();
  
  	dev_kfree_skb(xw->skb);
  
  	kfree(xw);
  }
  
  netdev_tx_t mac802154_tx(struct mac802154_priv *priv, struct sk_buff *skb,
  			 u8 page, u8 chan)
  {
  	struct xmit_work *work;
  	struct mac802154_sub_if_data *sdata;
  
  	if (!(priv->phy->channels_supported[page] & (1 << chan))) {
  		WARN_ON(1);
  		kfree_skb(skb);
  		return NETDEV_TX_OK;
  	}
  
  	mac802154_monitors_rx(mac802154_to_priv(&priv->hw), skb);
  
  	if (!(priv->hw.flags & IEEE802154_HW_OMIT_CKSUM)) {
  		u16 crc = crc_ccitt(0, skb->data, skb->len);
  		u8 *data = skb_put(skb, 2);
  		data[0] = crc & 0xff;
  		data[1] = crc >> 8;
  	}
  
  	if (skb_cow_head(skb, priv->hw.extra_tx_headroom)) {
  		kfree_skb(skb);
  		return NETDEV_TX_OK;
  	}
  
  	work = kzalloc(sizeof(struct xmit_work), GFP_ATOMIC);
  	if (!work) {
  		kfree_skb(skb);
  		return NETDEV_TX_BUSY;
  	}
  
  	/* Stop the netif queue on each sub_if_data object. */
  	rcu_read_lock();
  	list_for_each_entry_rcu(sdata, &priv->slaves, list)
  		netif_stop_queue(sdata->dev);
  	rcu_read_unlock();
  
  	INIT_WORK(&work->work, mac802154_xmit_worker);
  	work->skb = skb;
  	work->priv = priv;
  	work->page = page;
  	work->chan = chan;
  
  	queue_work(priv->dev_workqueue, &work->work);
  
  	return NETDEV_TX_OK;
  }