xref: /linux/net/mac802154/main.c (revision 320fefa9e2edc67011e235ea1d50f0d00ddfe004)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2007-2012 Siemens AG
4  *
5  * Written by:
6  * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/netdevice.h>
12 
13 #include <net/netlink.h>
14 #include <net/nl802154.h>
15 #include <net/mac802154.h>
16 #include <net/ieee802154_netdev.h>
17 #include <net/route.h>
18 #include <net/cfg802154.h>
19 
20 #include "ieee802154_i.h"
21 #include "cfg.h"
22 
23 static void ieee802154_tasklet_handler(struct tasklet_struct *t)
24 {
25 	struct ieee802154_local *local = from_tasklet(local, t, tasklet);
26 	struct sk_buff *skb;
27 
28 	while ((skb = skb_dequeue(&local->skb_queue))) {
29 		switch (skb->pkt_type) {
30 		case IEEE802154_RX_MSG:
31 			/* Clear skb->pkt_type in order to not confuse kernel
32 			 * netstack.
33 			 */
34 			skb->pkt_type = 0;
35 			ieee802154_rx(local, skb);
36 			break;
37 		default:
38 			WARN(1, "mac802154: Packet is of unknown type %d\n",
39 			     skb->pkt_type);
40 			kfree_skb(skb);
41 			break;
42 		}
43 	}
44 }
45 
46 struct ieee802154_hw *
47 ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
48 {
49 	struct wpan_phy *phy;
50 	struct ieee802154_local *local;
51 	size_t priv_size;
52 
53 	if (WARN_ON(!ops || !(ops->xmit_async || ops->xmit_sync) || !ops->ed ||
54 		    !ops->start || !ops->stop || !ops->set_channel))
55 		return NULL;
56 
57 	/* Ensure 32-byte alignment of our private data and hw private data.
58 	 * We use the wpan_phy priv data for both our ieee802154_local and for
59 	 * the driver's private data
60 	 *
61 	 * in memory it'll be like this:
62 	 *
63 	 * +-------------------------+
64 	 * | struct wpan_phy         |
65 	 * +-------------------------+
66 	 * | struct ieee802154_local |
67 	 * +-------------------------+
68 	 * | driver's private data   |
69 	 * +-------------------------+
70 	 *
71 	 * Due to ieee802154 layer isn't aware of driver and MAC structures,
72 	 * so lets align them here.
73 	 */
74 
75 	priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
76 
77 	phy = wpan_phy_new(&mac802154_config_ops, priv_size);
78 	if (!phy) {
79 		pr_err("failure to allocate master IEEE802.15.4 device\n");
80 		return NULL;
81 	}
82 
83 	phy->privid = mac802154_wpan_phy_privid;
84 
85 	local = wpan_phy_priv(phy);
86 	local->phy = phy;
87 	local->hw.phy = local->phy;
88 	local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
89 	local->ops = ops;
90 
91 	INIT_LIST_HEAD(&local->interfaces);
92 	mutex_init(&local->iflist_mtx);
93 
94 	tasklet_setup(&local->tasklet, ieee802154_tasklet_handler);
95 
96 	skb_queue_head_init(&local->skb_queue);
97 
98 	INIT_WORK(&local->sync_tx_work, ieee802154_xmit_sync_worker);
99 
100 	/* init supported flags with 802.15.4 default ranges */
101 	phy->supported.max_minbe = 8;
102 	phy->supported.min_maxbe = 3;
103 	phy->supported.max_maxbe = 8;
104 	phy->supported.min_frame_retries = 0;
105 	phy->supported.max_frame_retries = 7;
106 	phy->supported.max_csma_backoffs = 5;
107 	phy->supported.lbt = NL802154_SUPPORTED_BOOL_FALSE;
108 
109 	/* always supported */
110 	phy->supported.iftypes = BIT(NL802154_IFTYPE_NODE);
111 
112 	return &local->hw;
113 }
114 EXPORT_SYMBOL(ieee802154_alloc_hw);
115 
116 void ieee802154_configure_durations(struct wpan_phy *phy)
117 {
118 	u32 duration = 0;
119 
120 	switch (phy->current_page) {
121 	case 0:
122 		if (BIT(phy->current_channel) & 0x1)
123 			/* 868 MHz BPSK 802.15.4-2003: 20 ksym/s */
124 			duration = 50 * NSEC_PER_USEC;
125 		else if (BIT(phy->current_channel) & 0x7FE)
126 			/* 915 MHz BPSK	802.15.4-2003: 40 ksym/s */
127 			duration = 25 * NSEC_PER_USEC;
128 		else if (BIT(phy->current_channel) & 0x7FFF800)
129 			/* 2400 MHz O-QPSK 802.15.4-2006: 62.5 ksym/s */
130 			duration = 16 * NSEC_PER_USEC;
131 		break;
132 	case 2:
133 		if (BIT(phy->current_channel) & 0x1)
134 			/* 868 MHz O-QPSK 802.15.4-2006: 25 ksym/s */
135 			duration = 40 * NSEC_PER_USEC;
136 		else if (BIT(phy->current_channel) & 0x7FE)
137 			/* 915 MHz O-QPSK 802.15.4-2006: 62.5 ksym/s */
138 			duration = 16 * NSEC_PER_USEC;
139 		break;
140 	case 3:
141 		if (BIT(phy->current_channel) & 0x3FFF)
142 			/* 2.4 GHz CSS 802.15.4a-2007: 1/6 Msym/s */
143 			duration = 6 * NSEC_PER_USEC;
144 		break;
145 	default:
146 		break;
147 	}
148 
149 	if (!duration) {
150 		pr_debug("Unknown PHY symbol duration\n");
151 		return;
152 	}
153 
154 	phy->symbol_duration = duration;
155 	phy->lifs_period = (IEEE802154_LIFS_PERIOD * phy->symbol_duration) / NSEC_PER_SEC;
156 	phy->sifs_period = (IEEE802154_SIFS_PERIOD * phy->symbol_duration) / NSEC_PER_SEC;
157 }
158 EXPORT_SYMBOL(ieee802154_configure_durations);
159 
160 void ieee802154_free_hw(struct ieee802154_hw *hw)
161 {
162 	struct ieee802154_local *local = hw_to_local(hw);
163 
164 	BUG_ON(!list_empty(&local->interfaces));
165 
166 	mutex_destroy(&local->iflist_mtx);
167 
168 	wpan_phy_free(local->phy);
169 }
170 EXPORT_SYMBOL(ieee802154_free_hw);
171 
172 static void ieee802154_setup_wpan_phy_pib(struct wpan_phy *wpan_phy)
173 {
174 	/* TODO warn on empty symbol_duration
175 	 * Should be done when all drivers sets this value.
176 	 */
177 
178 	wpan_phy->lifs_period =
179 		(IEEE802154_LIFS_PERIOD * wpan_phy->symbol_duration) / 1000;
180 	wpan_phy->sifs_period =
181 		(IEEE802154_SIFS_PERIOD * wpan_phy->symbol_duration) / 1000;
182 }
183 
184 int ieee802154_register_hw(struct ieee802154_hw *hw)
185 {
186 	struct ieee802154_local *local = hw_to_local(hw);
187 	struct net_device *dev;
188 	int rc = -ENOSYS;
189 
190 	local->workqueue =
191 		create_singlethread_workqueue(wpan_phy_name(local->phy));
192 	if (!local->workqueue) {
193 		rc = -ENOMEM;
194 		goto out;
195 	}
196 
197 	hrtimer_init(&local->ifs_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
198 	local->ifs_timer.function = ieee802154_xmit_ifs_timer;
199 
200 	wpan_phy_set_dev(local->phy, local->hw.parent);
201 
202 	ieee802154_setup_wpan_phy_pib(local->phy);
203 
204 	ieee802154_configure_durations(local->phy);
205 
206 	if (!(hw->flags & IEEE802154_HW_CSMA_PARAMS)) {
207 		local->phy->supported.min_csma_backoffs = 4;
208 		local->phy->supported.max_csma_backoffs = 4;
209 		local->phy->supported.min_maxbe = 5;
210 		local->phy->supported.max_maxbe = 5;
211 		local->phy->supported.min_minbe = 3;
212 		local->phy->supported.max_minbe = 3;
213 	}
214 
215 	if (!(hw->flags & IEEE802154_HW_FRAME_RETRIES)) {
216 		local->phy->supported.min_frame_retries = 3;
217 		local->phy->supported.max_frame_retries = 3;
218 	}
219 
220 	if (hw->flags & IEEE802154_HW_PROMISCUOUS)
221 		local->phy->supported.iftypes |= BIT(NL802154_IFTYPE_MONITOR);
222 
223 	rc = wpan_phy_register(local->phy);
224 	if (rc < 0)
225 		goto out_wq;
226 
227 	rtnl_lock();
228 
229 	dev = ieee802154_if_add(local, "wpan%d", NET_NAME_ENUM,
230 				NL802154_IFTYPE_NODE,
231 				cpu_to_le64(0x0000000000000000ULL));
232 	if (IS_ERR(dev)) {
233 		rtnl_unlock();
234 		rc = PTR_ERR(dev);
235 		goto out_phy;
236 	}
237 
238 	rtnl_unlock();
239 
240 	return 0;
241 
242 out_phy:
243 	wpan_phy_unregister(local->phy);
244 out_wq:
245 	destroy_workqueue(local->workqueue);
246 out:
247 	return rc;
248 }
249 EXPORT_SYMBOL(ieee802154_register_hw);
250 
251 void ieee802154_unregister_hw(struct ieee802154_hw *hw)
252 {
253 	struct ieee802154_local *local = hw_to_local(hw);
254 
255 	tasklet_kill(&local->tasklet);
256 	flush_workqueue(local->workqueue);
257 
258 	rtnl_lock();
259 
260 	ieee802154_remove_interfaces(local);
261 
262 	rtnl_unlock();
263 
264 	destroy_workqueue(local->workqueue);
265 	wpan_phy_unregister(local->phy);
266 }
267 EXPORT_SYMBOL(ieee802154_unregister_hw);
268 
269 static int __init ieee802154_init(void)
270 {
271 	return ieee802154_iface_init();
272 }
273 
274 static void __exit ieee802154_exit(void)
275 {
276 	ieee802154_iface_exit();
277 
278 	rcu_barrier();
279 }
280 
281 subsys_initcall(ieee802154_init);
282 module_exit(ieee802154_exit);
283 
284 MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
285 MODULE_LICENSE("GPL v2");
286