xref: /linux/net/mac802154/main.c (revision 9e9f60108423f18a99c9cc93ef7f23490ecc709b)
1 /*
2  * Copyright (C) 2007-2012 Siemens AG
3  *
4  * Written by:
5  * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2
9  * as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/netdevice.h>
20 
21 #include <net/netlink.h>
22 #include <net/nl802154.h>
23 #include <net/mac802154.h>
24 #include <net/ieee802154_netdev.h>
25 #include <net/route.h>
26 #include <net/cfg802154.h>
27 
28 #include "ieee802154_i.h"
29 #include "cfg.h"
30 
31 static void ieee802154_tasklet_handler(unsigned long data)
32 {
33 	struct ieee802154_local *local = (struct ieee802154_local *)data;
34 	struct sk_buff *skb;
35 
36 	while ((skb = skb_dequeue(&local->skb_queue))) {
37 		switch (skb->pkt_type) {
38 		case IEEE802154_RX_MSG:
39 			/* Clear skb->pkt_type in order to not confuse kernel
40 			 * netstack.
41 			 */
42 			skb->pkt_type = 0;
43 			ieee802154_rx(&local->hw, skb);
44 			break;
45 		default:
46 			WARN(1, "mac802154: Packet is of unknown type %d\n",
47 			     skb->pkt_type);
48 			kfree_skb(skb);
49 			break;
50 		}
51 	}
52 }
53 
54 struct ieee802154_hw *
55 ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
56 {
57 	struct wpan_phy *phy;
58 	struct ieee802154_local *local;
59 	size_t priv_size;
60 
61 	if (!ops || !(ops->xmit_async || ops->xmit_sync) || !ops->ed ||
62 	    !ops->start || !ops->stop || !ops->set_channel) {
63 		pr_err("undefined IEEE802.15.4 device operations\n");
64 		return NULL;
65 	}
66 
67 	/* Ensure 32-byte alignment of our private data and hw private data.
68 	 * We use the wpan_phy priv data for both our ieee802154_local and for
69 	 * the driver's private data
70 	 *
71 	 * in memory it'll be like this:
72 	 *
73 	 * +-------------------------+
74 	 * | struct wpan_phy         |
75 	 * +-------------------------+
76 	 * | struct ieee802154_local |
77 	 * +-------------------------+
78 	 * | driver's private data   |
79 	 * +-------------------------+
80 	 *
81 	 * Due to ieee802154 layer isn't aware of driver and MAC structures,
82 	 * so lets align them here.
83 	 */
84 
85 	priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
86 
87 	phy = wpan_phy_new(&mac802154_config_ops, priv_size);
88 	if (!phy) {
89 		pr_err("failure to allocate master IEEE802.15.4 device\n");
90 		return NULL;
91 	}
92 
93 	phy->privid = mac802154_wpan_phy_privid;
94 
95 	local = wpan_phy_priv(phy);
96 	local->phy = phy;
97 	local->hw.phy = local->phy;
98 	local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
99 	local->ops = ops;
100 
101 	INIT_LIST_HEAD(&local->interfaces);
102 	mutex_init(&local->iflist_mtx);
103 
104 	tasklet_init(&local->tasklet,
105 		     ieee802154_tasklet_handler,
106 		     (unsigned long)local);
107 
108 	skb_queue_head_init(&local->skb_queue);
109 
110 	return &local->hw;
111 }
112 EXPORT_SYMBOL(ieee802154_alloc_hw);
113 
114 void ieee802154_free_hw(struct ieee802154_hw *hw)
115 {
116 	struct ieee802154_local *local = hw_to_local(hw);
117 
118 	BUG_ON(!list_empty(&local->interfaces));
119 
120 	mutex_destroy(&local->iflist_mtx);
121 
122 	wpan_phy_free(local->phy);
123 }
124 EXPORT_SYMBOL(ieee802154_free_hw);
125 
126 static void ieee802154_setup_wpan_phy_pib(struct wpan_phy *wpan_phy)
127 {
128 	/* TODO warn on empty symbol_duration
129 	 * Should be done when all drivers sets this value.
130 	 */
131 
132 	wpan_phy->lifs_period = IEEE802154_LIFS_PERIOD *
133 				wpan_phy->symbol_duration;
134 	wpan_phy->sifs_period = IEEE802154_SIFS_PERIOD *
135 				wpan_phy->symbol_duration;
136 }
137 
138 int ieee802154_register_hw(struct ieee802154_hw *hw)
139 {
140 	struct ieee802154_local *local = hw_to_local(hw);
141 	struct net_device *dev;
142 	int rc = -ENOSYS;
143 
144 	local->workqueue =
145 		create_singlethread_workqueue(wpan_phy_name(local->phy));
146 	if (!local->workqueue) {
147 		rc = -ENOMEM;
148 		goto out;
149 	}
150 
151 	hrtimer_init(&local->ifs_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
152 	local->ifs_timer.function = ieee802154_xmit_ifs_timer;
153 
154 	wpan_phy_set_dev(local->phy, local->hw.parent);
155 
156 	ieee802154_setup_wpan_phy_pib(local->phy);
157 
158 	rc = wpan_phy_register(local->phy);
159 	if (rc < 0)
160 		goto out_wq;
161 
162 	rtnl_lock();
163 
164 	dev = ieee802154_if_add(local, "wpan%d", NL802154_IFTYPE_NODE,
165 				cpu_to_le64(0x0000000000000000ULL));
166 	if (IS_ERR(dev)) {
167 		rtnl_unlock();
168 		rc = PTR_ERR(dev);
169 		goto out_wq;
170 	}
171 
172 	rtnl_unlock();
173 
174 	return 0;
175 
176 out_wq:
177 	destroy_workqueue(local->workqueue);
178 out:
179 	return rc;
180 }
181 EXPORT_SYMBOL(ieee802154_register_hw);
182 
183 void ieee802154_unregister_hw(struct ieee802154_hw *hw)
184 {
185 	struct ieee802154_local *local = hw_to_local(hw);
186 
187 	tasklet_kill(&local->tasklet);
188 	flush_workqueue(local->workqueue);
189 	destroy_workqueue(local->workqueue);
190 
191 	rtnl_lock();
192 
193 	ieee802154_remove_interfaces(local);
194 
195 	rtnl_unlock();
196 
197 	wpan_phy_unregister(local->phy);
198 }
199 EXPORT_SYMBOL(ieee802154_unregister_hw);
200 
201 static int __init ieee802154_init(void)
202 {
203 	return ieee802154_iface_init();
204 }
205 
206 static void __exit ieee802154_exit(void)
207 {
208 	ieee802154_iface_exit();
209 
210 	rcu_barrier();
211 }
212 
213 subsys_initcall(ieee802154_init);
214 module_exit(ieee802154_exit);
215 
216 MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
217 MODULE_LICENSE("GPL v2");
218