1/*
2 * Loopback IEEE 802.15.4 interface
3 *
4 * Copyright 2007-2012 Siemens AG
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * Written by:
16 * Sergey Lapin <slapin@ossfans.org>
17 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
18 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
19 */
20
21#include <linux/module.h>
22#include <linux/timer.h>
23#include <linux/platform_device.h>
24#include <linux/netdevice.h>
25#include <linux/device.h>
26#include <linux/spinlock.h>
27#include <net/mac802154.h>
28#include <net/cfg802154.h>
29
30static int numlbs = 1;
31
32struct fakelb_dev_priv {
33	struct ieee802154_hw *hw;
34
35	struct list_head list;
36	struct fakelb_priv *fake;
37
38	spinlock_t lock;
39	bool working;
40};
41
42struct fakelb_priv {
43	struct list_head list;
44	rwlock_t lock;
45};
46
47static int
48fakelb_hw_ed(struct ieee802154_hw *hw, u8 *level)
49{
50	BUG_ON(!level);
51	*level = 0xbe;
52
53	return 0;
54}
55
56static int
57fakelb_hw_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
58{
59	pr_debug("set channel to %d\n", channel);
60
61	return 0;
62}
63
64static void
65fakelb_hw_deliver(struct fakelb_dev_priv *priv, struct sk_buff *skb)
66{
67	struct sk_buff *newskb;
68
69	spin_lock(&priv->lock);
70	if (priv->working) {
71		newskb = pskb_copy(skb, GFP_ATOMIC);
72		ieee802154_rx_irqsafe(priv->hw, newskb, 0xcc);
73	}
74	spin_unlock(&priv->lock);
75}
76
77static int
78fakelb_hw_xmit(struct ieee802154_hw *hw, struct sk_buff *skb)
79{
80	struct fakelb_dev_priv *priv = hw->priv;
81	struct fakelb_priv *fake = priv->fake;
82
83	read_lock_bh(&fake->lock);
84	if (priv->list.next == priv->list.prev) {
85		/* we are the only one device */
86		fakelb_hw_deliver(priv, skb);
87	} else {
88		struct fakelb_dev_priv *dp;
89		list_for_each_entry(dp, &priv->fake->list, list) {
90			if (dp != priv &&
91			    (dp->hw->phy->current_channel ==
92			     priv->hw->phy->current_channel))
93				fakelb_hw_deliver(dp, skb);
94		}
95	}
96	read_unlock_bh(&fake->lock);
97
98	return 0;
99}
100
101static int
102fakelb_hw_start(struct ieee802154_hw *hw) {
103	struct fakelb_dev_priv *priv = hw->priv;
104	int ret = 0;
105
106	spin_lock(&priv->lock);
107	if (priv->working)
108		ret = -EBUSY;
109	else
110		priv->working = 1;
111	spin_unlock(&priv->lock);
112
113	return ret;
114}
115
116static void
117fakelb_hw_stop(struct ieee802154_hw *hw) {
118	struct fakelb_dev_priv *priv = hw->priv;
119
120	spin_lock(&priv->lock);
121	priv->working = 0;
122	spin_unlock(&priv->lock);
123}
124
125static const struct ieee802154_ops fakelb_ops = {
126	.owner = THIS_MODULE,
127	.xmit_sync = fakelb_hw_xmit,
128	.ed = fakelb_hw_ed,
129	.set_channel = fakelb_hw_channel,
130	.start = fakelb_hw_start,
131	.stop = fakelb_hw_stop,
132};
133
134/* Number of dummy devices to be set up by this module. */
135module_param(numlbs, int, 0);
136MODULE_PARM_DESC(numlbs, " number of pseudo devices");
137
138static int fakelb_add_one(struct device *dev, struct fakelb_priv *fake)
139{
140	struct fakelb_dev_priv *priv;
141	int err;
142	struct ieee802154_hw *hw;
143
144	hw = ieee802154_alloc_hw(sizeof(*priv), &fakelb_ops);
145	if (!hw)
146		return -ENOMEM;
147
148	priv = hw->priv;
149	priv->hw = hw;
150
151	/* 868 MHz BPSK	802.15.4-2003 */
152	hw->phy->channels_supported[0] |= 1;
153	/* 915 MHz BPSK	802.15.4-2003 */
154	hw->phy->channels_supported[0] |= 0x7fe;
155	/* 2.4 GHz O-QPSK 802.15.4-2003 */
156	hw->phy->channels_supported[0] |= 0x7FFF800;
157	/* 868 MHz ASK 802.15.4-2006 */
158	hw->phy->channels_supported[1] |= 1;
159	/* 915 MHz ASK 802.15.4-2006 */
160	hw->phy->channels_supported[1] |= 0x7fe;
161	/* 868 MHz O-QPSK 802.15.4-2006 */
162	hw->phy->channels_supported[2] |= 1;
163	/* 915 MHz O-QPSK 802.15.4-2006 */
164	hw->phy->channels_supported[2] |= 0x7fe;
165	/* 2.4 GHz CSS 802.15.4a-2007 */
166	hw->phy->channels_supported[3] |= 0x3fff;
167	/* UWB Sub-gigahertz 802.15.4a-2007 */
168	hw->phy->channels_supported[4] |= 1;
169	/* UWB Low band 802.15.4a-2007 */
170	hw->phy->channels_supported[4] |= 0x1e;
171	/* UWB High band 802.15.4a-2007 */
172	hw->phy->channels_supported[4] |= 0xffe0;
173	/* 750 MHz O-QPSK 802.15.4c-2009 */
174	hw->phy->channels_supported[5] |= 0xf;
175	/* 750 MHz MPSK 802.15.4c-2009 */
176	hw->phy->channels_supported[5] |= 0xf0;
177	/* 950 MHz BPSK 802.15.4d-2009 */
178	hw->phy->channels_supported[6] |= 0x3ff;
179	/* 950 MHz GFSK 802.15.4d-2009 */
180	hw->phy->channels_supported[6] |= 0x3ffc00;
181
182	INIT_LIST_HEAD(&priv->list);
183	priv->fake = fake;
184
185	spin_lock_init(&priv->lock);
186
187	hw->parent = dev;
188
189	err = ieee802154_register_hw(hw);
190	if (err)
191		goto err_reg;
192
193	write_lock_bh(&fake->lock);
194	list_add_tail(&priv->list, &fake->list);
195	write_unlock_bh(&fake->lock);
196
197	return 0;
198
199err_reg:
200	ieee802154_free_hw(priv->hw);
201	return err;
202}
203
204static void fakelb_del(struct fakelb_dev_priv *priv)
205{
206	write_lock_bh(&priv->fake->lock);
207	list_del(&priv->list);
208	write_unlock_bh(&priv->fake->lock);
209
210	ieee802154_unregister_hw(priv->hw);
211	ieee802154_free_hw(priv->hw);
212}
213
214static int fakelb_probe(struct platform_device *pdev)
215{
216	struct fakelb_priv *priv;
217	struct fakelb_dev_priv *dp;
218	int err = -ENOMEM;
219	int i;
220
221	priv = devm_kzalloc(&pdev->dev, sizeof(struct fakelb_priv),
222			    GFP_KERNEL);
223	if (!priv)
224		goto err_alloc;
225
226	INIT_LIST_HEAD(&priv->list);
227	rwlock_init(&priv->lock);
228
229	for (i = 0; i < numlbs; i++) {
230		err = fakelb_add_one(&pdev->dev, priv);
231		if (err < 0)
232			goto err_slave;
233	}
234
235	platform_set_drvdata(pdev, priv);
236	dev_info(&pdev->dev, "added ieee802154 hardware\n");
237	return 0;
238
239err_slave:
240	list_for_each_entry(dp, &priv->list, list)
241		fakelb_del(dp);
242err_alloc:
243	return err;
244}
245
246static int fakelb_remove(struct platform_device *pdev)
247{
248	struct fakelb_priv *priv = platform_get_drvdata(pdev);
249	struct fakelb_dev_priv *dp, *temp;
250
251	list_for_each_entry_safe(dp, temp, &priv->list, list)
252		fakelb_del(dp);
253
254	return 0;
255}
256
257static struct platform_device *ieee802154fake_dev;
258
259static struct platform_driver ieee802154fake_driver = {
260	.probe = fakelb_probe,
261	.remove = fakelb_remove,
262	.driver = {
263			.name = "ieee802154fakelb",
264	},
265};
266
267static __init int fakelb_init_module(void)
268{
269	ieee802154fake_dev = platform_device_register_simple(
270			     "ieee802154fakelb", -1, NULL, 0);
271	return platform_driver_register(&ieee802154fake_driver);
272}
273
274static __exit void fake_remove_module(void)
275{
276	platform_driver_unregister(&ieee802154fake_driver);
277	platform_device_unregister(ieee802154fake_dev);
278}
279
280module_init(fakelb_init_module);
281module_exit(fake_remove_module);
282MODULE_LICENSE("GPL");
283