xref: /linux/net/mac802154/main.c (revision 1a2ac6d7ecdcde74a4e16f31de64124160fc7237)
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 	INIT_LIST_HEAD(&local->rx_beacon_list);
93 	mutex_init(&local->iflist_mtx);
94 
95 	tasklet_setup(&local->tasklet, ieee802154_tasklet_handler);
96 
97 	skb_queue_head_init(&local->skb_queue);
98 
99 	INIT_WORK(&local->sync_tx_work, ieee802154_xmit_sync_worker);
100 	INIT_DELAYED_WORK(&local->scan_work, mac802154_scan_worker);
101 	INIT_WORK(&local->rx_beacon_work, mac802154_rx_beacon_worker);
102 	INIT_DELAYED_WORK(&local->beacon_work, mac802154_beacon_worker);
103 
104 	/* init supported flags with 802.15.4 default ranges */
105 	phy->supported.max_minbe = 8;
106 	phy->supported.min_maxbe = 3;
107 	phy->supported.max_maxbe = 8;
108 	phy->supported.min_frame_retries = 0;
109 	phy->supported.max_frame_retries = 7;
110 	phy->supported.max_csma_backoffs = 5;
111 	phy->supported.lbt = NL802154_SUPPORTED_BOOL_FALSE;
112 
113 	/* always supported */
114 	phy->supported.iftypes = BIT(NL802154_IFTYPE_NODE) | BIT(NL802154_IFTYPE_COORD);
115 
116 	return &local->hw;
117 }
118 EXPORT_SYMBOL(ieee802154_alloc_hw);
119 
120 void ieee802154_configure_durations(struct wpan_phy *phy,
121 				    unsigned int page, unsigned int channel)
122 {
123 	u32 duration = 0;
124 
125 	switch (page) {
126 	case 0:
127 		if (BIT(channel) & 0x1)
128 			/* 868 MHz BPSK 802.15.4-2003: 20 ksym/s */
129 			duration = 50 * NSEC_PER_USEC;
130 		else if (BIT(channel) & 0x7FE)
131 			/* 915 MHz BPSK	802.15.4-2003: 40 ksym/s */
132 			duration = 25 * NSEC_PER_USEC;
133 		else if (BIT(channel) & 0x7FFF800)
134 			/* 2400 MHz O-QPSK 802.15.4-2006: 62.5 ksym/s */
135 			duration = 16 * NSEC_PER_USEC;
136 		break;
137 	case 2:
138 		if (BIT(channel) & 0x1)
139 			/* 868 MHz O-QPSK 802.15.4-2006: 25 ksym/s */
140 			duration = 40 * NSEC_PER_USEC;
141 		else if (BIT(channel) & 0x7FE)
142 			/* 915 MHz O-QPSK 802.15.4-2006: 62.5 ksym/s */
143 			duration = 16 * NSEC_PER_USEC;
144 		break;
145 	case 3:
146 		if (BIT(channel) & 0x3FFF)
147 			/* 2.4 GHz CSS 802.15.4a-2007: 1/6 Msym/s */
148 			duration = 6 * NSEC_PER_USEC;
149 		break;
150 	default:
151 		break;
152 	}
153 
154 	if (!duration) {
155 		pr_debug("Unknown PHY symbol duration\n");
156 		return;
157 	}
158 
159 	phy->symbol_duration = duration;
160 	phy->lifs_period = (IEEE802154_LIFS_PERIOD * phy->symbol_duration) / NSEC_PER_SEC;
161 	phy->sifs_period = (IEEE802154_SIFS_PERIOD * phy->symbol_duration) / NSEC_PER_SEC;
162 }
163 EXPORT_SYMBOL(ieee802154_configure_durations);
164 
165 void ieee802154_free_hw(struct ieee802154_hw *hw)
166 {
167 	struct ieee802154_local *local = hw_to_local(hw);
168 
169 	BUG_ON(!list_empty(&local->interfaces));
170 
171 	mutex_destroy(&local->iflist_mtx);
172 
173 	wpan_phy_free(local->phy);
174 }
175 EXPORT_SYMBOL(ieee802154_free_hw);
176 
177 static void ieee802154_setup_wpan_phy_pib(struct wpan_phy *wpan_phy)
178 {
179 	/* TODO warn on empty symbol_duration
180 	 * Should be done when all drivers sets this value.
181 	 */
182 
183 	wpan_phy->lifs_period =
184 		(IEEE802154_LIFS_PERIOD * wpan_phy->symbol_duration) / 1000;
185 	wpan_phy->sifs_period =
186 		(IEEE802154_SIFS_PERIOD * wpan_phy->symbol_duration) / 1000;
187 }
188 
189 int ieee802154_register_hw(struct ieee802154_hw *hw)
190 {
191 	struct ieee802154_local *local = hw_to_local(hw);
192 	char mac_wq_name[IFNAMSIZ + 10] = {};
193 	struct net_device *dev;
194 	int rc = -ENOSYS;
195 
196 	local->workqueue =
197 		create_singlethread_workqueue(wpan_phy_name(local->phy));
198 	if (!local->workqueue) {
199 		rc = -ENOMEM;
200 		goto out;
201 	}
202 
203 	snprintf(mac_wq_name, IFNAMSIZ + 10, "%s-mac-cmds", wpan_phy_name(local->phy));
204 	local->mac_wq =	create_singlethread_workqueue(mac_wq_name);
205 	if (!local->mac_wq) {
206 		rc = -ENOMEM;
207 		goto out_wq;
208 	}
209 
210 	hrtimer_init(&local->ifs_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
211 	local->ifs_timer.function = ieee802154_xmit_ifs_timer;
212 
213 	wpan_phy_set_dev(local->phy, local->hw.parent);
214 
215 	ieee802154_setup_wpan_phy_pib(local->phy);
216 
217 	ieee802154_configure_durations(local->phy, local->phy->current_page,
218 				       local->phy->current_channel);
219 
220 	if (!(hw->flags & IEEE802154_HW_CSMA_PARAMS)) {
221 		local->phy->supported.min_csma_backoffs = 4;
222 		local->phy->supported.max_csma_backoffs = 4;
223 		local->phy->supported.min_maxbe = 5;
224 		local->phy->supported.max_maxbe = 5;
225 		local->phy->supported.min_minbe = 3;
226 		local->phy->supported.max_minbe = 3;
227 	}
228 
229 	if (!(hw->flags & IEEE802154_HW_FRAME_RETRIES)) {
230 		local->phy->supported.min_frame_retries = 3;
231 		local->phy->supported.max_frame_retries = 3;
232 	}
233 
234 	if (hw->flags & IEEE802154_HW_PROMISCUOUS)
235 		local->phy->supported.iftypes |= BIT(NL802154_IFTYPE_MONITOR);
236 
237 	rc = wpan_phy_register(local->phy);
238 	if (rc < 0)
239 		goto out_mac_wq;
240 
241 	rtnl_lock();
242 
243 	dev = ieee802154_if_add(local, "wpan%d", NET_NAME_ENUM,
244 				NL802154_IFTYPE_NODE,
245 				cpu_to_le64(0x0000000000000000ULL));
246 	if (IS_ERR(dev)) {
247 		rtnl_unlock();
248 		rc = PTR_ERR(dev);
249 		goto out_phy;
250 	}
251 
252 	rtnl_unlock();
253 
254 	return 0;
255 
256 out_phy:
257 	wpan_phy_unregister(local->phy);
258 out_mac_wq:
259 	destroy_workqueue(local->mac_wq);
260 out_wq:
261 	destroy_workqueue(local->workqueue);
262 out:
263 	return rc;
264 }
265 EXPORT_SYMBOL(ieee802154_register_hw);
266 
267 void ieee802154_unregister_hw(struct ieee802154_hw *hw)
268 {
269 	struct ieee802154_local *local = hw_to_local(hw);
270 
271 	tasklet_kill(&local->tasklet);
272 	flush_workqueue(local->workqueue);
273 
274 	rtnl_lock();
275 
276 	ieee802154_remove_interfaces(local);
277 
278 	rtnl_unlock();
279 
280 	destroy_workqueue(local->mac_wq);
281 	destroy_workqueue(local->workqueue);
282 	wpan_phy_unregister(local->phy);
283 }
284 EXPORT_SYMBOL(ieee802154_unregister_hw);
285 
286 static int __init ieee802154_init(void)
287 {
288 	return ieee802154_iface_init();
289 }
290 
291 static void __exit ieee802154_exit(void)
292 {
293 	ieee802154_iface_exit();
294 
295 	rcu_barrier();
296 }
297 
298 subsys_initcall(ieee802154_init);
299 module_exit(ieee802154_exit);
300 
301 MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
302 MODULE_LICENSE("GPL v2");
303