aboutsummaryrefslogtreecommitdiff
path: root/drivers/uwb/driver.c
blob: 3e5454aba5d4b3e37303b9ec7f8ebcfd229b96e2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/*
 * Ultra Wide Band
 * Driver initialization, etc
 *
 * Copyright (C) 2005-2006 Intel Corporation
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 *
 * FIXME: docs
 *
 * Life cycle: FIXME: explain
 *
 *  UWB radio controller:
 *
 *    1. alloc a uwb_rc, zero it
 *    2. call uwb_rc_init() on it to set it up + ops (won't do any
 *       kind of allocation)
 *    3. register (now it is owned by the UWB stack--deregister before
 *       freeing/destroying).
 *    4. It lives on it's own now (UWB stack handles)--when it
 *       disconnects, call unregister()
 *    5. free it.
 *
 *    Make sure you have a reference to the uwb_rc before calling
 *    any of the UWB API functions.
 *
 * TODO:
 *
 * 1. Locking and life cycle management is crappy still. All entry
 *    points to the UWB HCD API assume you have a reference on the
 *    uwb_rc structure and that it won't go away. They mutex lock it
 *    before doing anything.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/kdev_t.h>
#include <linux/random.h>

#include "uwb-internal.h"


/* UWB stack attributes (or 'global' constants) */


/**
 * If a beacon disappears for longer than this, then we consider the
 * device who was represented by that beacon to be gone.
 *
 * ECMA-368[17.2.3, last para] establishes that a device must not
 * consider a device to be its neighbour if he doesn't receive a beacon
 * for more than mMaxLostBeacons. mMaxLostBeacons is defined in
 * ECMA-368[17.16] as 3; because we can get only one beacon per
 * superframe, that'd be 3 * 65ms = 195 ~ 200 ms. Let's give it time
 * for jitter and stuff and make it 500 ms.
 */
unsigned long beacon_timeout_ms = 500;

static
ssize_t beacon_timeout_ms_show(struct class *class,
				struct class_attribute *attr,
				char *buf)
{
	return scnprintf(buf, PAGE_SIZE, "%lu\n", beacon_timeout_ms);
}

static
ssize_t beacon_timeout_ms_store(struct class *class,
				struct class_attribute *attr,
				const char *buf, size_t size)
{
	unsigned long bt;
	ssize_t result;
	result = sscanf(buf, "%lu", &bt);
	if (result != 1)
		return -EINVAL;
	beacon_timeout_ms = bt;
	return size;
}

static struct class_attribute uwb_class_attrs[] = {
	__ATTR(beacon_timeout_ms, S_IWUSR | S_IRUGO,
	       beacon_timeout_ms_show, beacon_timeout_ms_store),
	__ATTR_NULL,
};

/** Device model classes */
struct class uwb_rc_class = {
	.name        = "uwb_rc",
	.class_attrs = uwb_class_attrs,
};


static int __init uwb_subsys_init(void)
{
	int result = 0;

	result = uwb_est_create();
	if (result < 0) {
		printk(KERN_ERR "uwb: Can't initialize EST subsystem\n");
		goto error_est_init;
	}

	result = class_register(&uwb_rc_class);
	if (result < 0)
		goto error_uwb_rc_class_register;
	uwb_dbg_init();
	return 0;

error_uwb_rc_class_register:
	uwb_est_destroy();
error_est_init:
	return result;
}
module_init(uwb_subsys_init);

static void __exit uwb_subsys_exit(void)
{
	uwb_dbg_exit();
	class_unregister(&uwb_rc_class);
	uwb_est_destroy();
	return;
}
module_exit(uwb_subsys_exit);

MODULE_AUTHOR("Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>");
MODULE_DESCRIPTION("Ultra Wide Band core");
MODULE_LICENSE("GPL");