xref: /openbmc/linux/net/mac802154/main.c (revision feac8c8b)
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, 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 (WARN_ON(!ops || !(ops->xmit_async || ops->xmit_sync) || !ops->ed ||
62 		    !ops->start || !ops->stop || !ops->set_channel))
63 		return NULL;
64 
65 	/* Ensure 32-byte alignment of our private data and hw private data.
66 	 * We use the wpan_phy priv data for both our ieee802154_local and for
67 	 * the driver's private data
68 	 *
69 	 * in memory it'll be like this:
70 	 *
71 	 * +-------------------------+
72 	 * | struct wpan_phy         |
73 	 * +-------------------------+
74 	 * | struct ieee802154_local |
75 	 * +-------------------------+
76 	 * | driver's private data   |
77 	 * +-------------------------+
78 	 *
79 	 * Due to ieee802154 layer isn't aware of driver and MAC structures,
80 	 * so lets align them here.
81 	 */
82 
83 	priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
84 
85 	phy = wpan_phy_new(&mac802154_config_ops, priv_size);
86 	if (!phy) {
87 		pr_err("failure to allocate master IEEE802.15.4 device\n");
88 		return NULL;
89 	}
90 
91 	phy->privid = mac802154_wpan_phy_privid;
92 
93 	local = wpan_phy_priv(phy);
94 	local->phy = phy;
95 	local->hw.phy = local->phy;
96 	local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
97 	local->ops = ops;
98 
99 	INIT_LIST_HEAD(&local->interfaces);
100 	mutex_init(&local->iflist_mtx);
101 
102 	tasklet_init(&local->tasklet,
103 		     ieee802154_tasklet_handler,
104 		     (unsigned long)local);
105 
106 	skb_queue_head_init(&local->skb_queue);
107 
108 	INIT_WORK(&local->tx_work, ieee802154_xmit_worker);
109 
110 	/* init supported flags with 802.15.4 default ranges */
111 	phy->supported.max_minbe = 8;
112 	phy->supported.min_maxbe = 3;
113 	phy->supported.max_maxbe = 8;
114 	phy->supported.min_frame_retries = 0;
115 	phy->supported.max_frame_retries = 7;
116 	phy->supported.max_csma_backoffs = 5;
117 	phy->supported.lbt = NL802154_SUPPORTED_BOOL_FALSE;
118 
119 	/* always supported */
120 	phy->supported.iftypes = BIT(NL802154_IFTYPE_NODE);
121 
122 	return &local->hw;
123 }
124 EXPORT_SYMBOL(ieee802154_alloc_hw);
125 
126 void ieee802154_free_hw(struct ieee802154_hw *hw)
127 {
128 	struct ieee802154_local *local = hw_to_local(hw);
129 
130 	BUG_ON(!list_empty(&local->interfaces));
131 
132 	mutex_destroy(&local->iflist_mtx);
133 
134 	wpan_phy_free(local->phy);
135 }
136 EXPORT_SYMBOL(ieee802154_free_hw);
137 
138 static void ieee802154_setup_wpan_phy_pib(struct wpan_phy *wpan_phy)
139 {
140 	/* TODO warn on empty symbol_duration
141 	 * Should be done when all drivers sets this value.
142 	 */
143 
144 	wpan_phy->lifs_period = IEEE802154_LIFS_PERIOD *
145 				wpan_phy->symbol_duration;
146 	wpan_phy->sifs_period = IEEE802154_SIFS_PERIOD *
147 				wpan_phy->symbol_duration;
148 }
149 
150 int ieee802154_register_hw(struct ieee802154_hw *hw)
151 {
152 	struct ieee802154_local *local = hw_to_local(hw);
153 	struct net_device *dev;
154 	int rc = -ENOSYS;
155 
156 	local->workqueue =
157 		create_singlethread_workqueue(wpan_phy_name(local->phy));
158 	if (!local->workqueue) {
159 		rc = -ENOMEM;
160 		goto out;
161 	}
162 
163 	hrtimer_init(&local->ifs_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
164 	local->ifs_timer.function = ieee802154_xmit_ifs_timer;
165 
166 	wpan_phy_set_dev(local->phy, local->hw.parent);
167 
168 	ieee802154_setup_wpan_phy_pib(local->phy);
169 
170 	if (!(hw->flags & IEEE802154_HW_CSMA_PARAMS)) {
171 		local->phy->supported.min_csma_backoffs = 4;
172 		local->phy->supported.max_csma_backoffs = 4;
173 		local->phy->supported.min_maxbe = 5;
174 		local->phy->supported.max_maxbe = 5;
175 		local->phy->supported.min_minbe = 3;
176 		local->phy->supported.max_minbe = 3;
177 	}
178 
179 	if (!(hw->flags & IEEE802154_HW_FRAME_RETRIES)) {
180 		local->phy->supported.min_frame_retries = 3;
181 		local->phy->supported.max_frame_retries = 3;
182 	}
183 
184 	if (hw->flags & IEEE802154_HW_PROMISCUOUS)
185 		local->phy->supported.iftypes |= BIT(NL802154_IFTYPE_MONITOR);
186 
187 	rc = wpan_phy_register(local->phy);
188 	if (rc < 0)
189 		goto out_wq;
190 
191 	rtnl_lock();
192 
193 	dev = ieee802154_if_add(local, "wpan%d", NET_NAME_ENUM,
194 				NL802154_IFTYPE_NODE,
195 				cpu_to_le64(0x0000000000000000ULL));
196 	if (IS_ERR(dev)) {
197 		rtnl_unlock();
198 		rc = PTR_ERR(dev);
199 		goto out_phy;
200 	}
201 
202 	rtnl_unlock();
203 
204 	return 0;
205 
206 out_phy:
207 	wpan_phy_unregister(local->phy);
208 out_wq:
209 	destroy_workqueue(local->workqueue);
210 out:
211 	return rc;
212 }
213 EXPORT_SYMBOL(ieee802154_register_hw);
214 
215 void ieee802154_unregister_hw(struct ieee802154_hw *hw)
216 {
217 	struct ieee802154_local *local = hw_to_local(hw);
218 
219 	tasklet_kill(&local->tasklet);
220 	flush_workqueue(local->workqueue);
221 
222 	rtnl_lock();
223 
224 	ieee802154_remove_interfaces(local);
225 
226 	rtnl_unlock();
227 
228 	destroy_workqueue(local->workqueue);
229 	wpan_phy_unregister(local->phy);
230 }
231 EXPORT_SYMBOL(ieee802154_unregister_hw);
232 
233 static int __init ieee802154_init(void)
234 {
235 	return ieee802154_iface_init();
236 }
237 
238 static void __exit ieee802154_exit(void)
239 {
240 	ieee802154_iface_exit();
241 
242 	rcu_barrier();
243 }
244 
245 subsys_initcall(ieee802154_init);
246 module_exit(ieee802154_exit);
247 
248 MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
249 MODULE_LICENSE("GPL v2");
250