Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
7785925d | 2 | * w1_int.c |
1da177e4 LT |
3 | * |
4 | * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru> | |
7785925d | 5 | * |
1da177e4 LT |
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 as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
20 | */ | |
21 | ||
22 | #include <linux/kernel.h> | |
23 | #include <linux/list.h> | |
24 | #include <linux/delay.h> | |
674a396c | 25 | #include <linux/kthread.h> |
1da177e4 LT |
26 | |
27 | #include "w1.h" | |
28 | #include "w1_log.h" | |
29 | #include "w1_netlink.h" | |
30 | ||
31 | static u32 w1_ids = 1; | |
32 | ||
7785925d EP |
33 | static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl, |
34 | struct device_driver *driver, | |
35 | struct device *device) | |
1da177e4 LT |
36 | { |
37 | struct w1_master *dev; | |
38 | int err; | |
39 | ||
40 | /* | |
41 | * We are in process context(kernel thread), so can sleep. | |
42 | */ | |
43 | dev = kmalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL); | |
44 | if (!dev) { | |
45 | printk(KERN_ERR | |
46 | "Failed to allocate %zd bytes for new w1 device.\n", | |
47 | sizeof(struct w1_master)); | |
48 | return NULL; | |
49 | } | |
50 | ||
51 | memset(dev, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master)); | |
52 | ||
53 | dev->bus_master = (struct w1_bus_master *)(dev + 1); | |
54 | ||
7785925d EP |
55 | dev->owner = THIS_MODULE; |
56 | dev->max_slave_count = slave_count; | |
57 | dev->slave_count = 0; | |
58 | dev->attempts = 0; | |
7785925d EP |
59 | dev->initialized = 0; |
60 | dev->id = id; | |
1da177e4 | 61 | dev->slave_ttl = slave_ttl; |
2a9d0c17 | 62 | dev->search_count = -1; /* continual scan */ |
1da177e4 LT |
63 | |
64 | atomic_set(&dev->refcnt, 2); | |
65 | ||
66 | INIT_LIST_HEAD(&dev->slist); | |
abd52a13 | 67 | mutex_init(&dev->mutex); |
1da177e4 | 68 | |
1da177e4 LT |
69 | memcpy(&dev->dev, device, sizeof(struct device)); |
70 | snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id), | |
71 | "w1_bus_master%u", dev->id); | |
72 | snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id); | |
73 | ||
74 | dev->driver = driver; | |
75 | ||
1da177e4 | 76 | dev->seq = 1; |
1da177e4 LT |
77 | |
78 | err = device_register(&dev->dev); | |
79 | if (err) { | |
80 | printk(KERN_ERR "Failed to register master device. err=%d\n", err); | |
1da177e4 LT |
81 | memset(dev, 0, sizeof(struct w1_master)); |
82 | kfree(dev); | |
83 | dev = NULL; | |
84 | } | |
85 | ||
86 | return dev; | |
87 | } | |
88 | ||
2c5bfdac | 89 | static void w1_free_dev(struct w1_master *dev) |
1da177e4 LT |
90 | { |
91 | device_unregister(&dev->dev); | |
1da177e4 LT |
92 | } |
93 | ||
94 | int w1_add_master_device(struct w1_bus_master *master) | |
95 | { | |
96 | struct w1_master *dev; | |
97 | int retval = 0; | |
98 | struct w1_netlink_msg msg; | |
99 | ||
be57ce26 EP |
100 | /* validate minimum functionality */ |
101 | if (!(master->touch_bit && master->reset_bus) && | |
6adf87bd EP |
102 | !(master->write_bit && master->read_bit)) { |
103 | printk(KERN_ERR "w1_add_master_device: invalid function set\n"); | |
104 | return(-EINVAL); | |
be57ce26 EP |
105 | } |
106 | ||
7f772ed8 | 107 | dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_master_driver, &w1_master_device); |
1da177e4 LT |
108 | if (!dev) |
109 | return -ENOMEM; | |
110 | ||
674a396c EP |
111 | dev->thread = kthread_run(&w1_process, dev, "%s", dev->name); |
112 | if (IS_ERR(dev->thread)) { | |
113 | retval = PTR_ERR(dev->thread); | |
1da177e4 LT |
114 | dev_err(&dev->dev, |
115 | "Failed to create new kernel thread. err=%d\n", | |
674a396c | 116 | retval); |
1da177e4 LT |
117 | goto err_out_free_dev; |
118 | } | |
119 | ||
120 | retval = w1_create_master_attributes(dev); | |
121 | if (retval) | |
122 | goto err_out_kill_thread; | |
123 | ||
124 | memcpy(dev->bus_master, master, sizeof(struct w1_bus_master)); | |
125 | ||
126 | dev->initialized = 1; | |
127 | ||
abd52a13 | 128 | mutex_lock(&w1_mlock); |
1da177e4 | 129 | list_add(&dev->w1_master_entry, &w1_masters); |
abd52a13 | 130 | mutex_unlock(&w1_mlock); |
1da177e4 | 131 | |
12003375 | 132 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 133 | msg.id.mst.id = dev->id; |
1da177e4 LT |
134 | msg.type = W1_MASTER_ADD; |
135 | w1_netlink_send(dev, &msg); | |
136 | ||
137 | return 0; | |
138 | ||
139 | err_out_kill_thread: | |
674a396c | 140 | kthread_stop(dev->thread); |
1da177e4 LT |
141 | err_out_free_dev: |
142 | w1_free_dev(dev); | |
143 | ||
144 | return retval; | |
145 | } | |
146 | ||
147 | void __w1_remove_master_device(struct w1_master *dev) | |
148 | { | |
1da177e4 LT |
149 | struct w1_netlink_msg msg; |
150 | ||
6adf87bd | 151 | set_bit(W1_MASTER_NEED_EXIT, &dev->flags); |
674a396c | 152 | kthread_stop(dev->thread); |
1da177e4 LT |
153 | |
154 | while (atomic_read(&dev->refcnt)) { | |
674a396c | 155 | dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n", |
1da177e4 LT |
156 | dev->name, atomic_read(&dev->refcnt)); |
157 | ||
158 | if (msleep_interruptible(1000)) | |
159 | flush_signals(current); | |
160 | } | |
161 | ||
12003375 | 162 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 163 | msg.id.mst.id = dev->id; |
1da177e4 LT |
164 | msg.type = W1_MASTER_REMOVE; |
165 | w1_netlink_send(dev, &msg); | |
166 | ||
167 | w1_free_dev(dev); | |
168 | } | |
169 | ||
170 | void w1_remove_master_device(struct w1_bus_master *bm) | |
171 | { | |
172 | struct w1_master *dev = NULL; | |
1da177e4 | 173 | |
7785925d | 174 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
1da177e4 LT |
175 | if (!dev->initialized) |
176 | continue; | |
177 | ||
178 | if (dev->bus_master->data == bm->data) | |
179 | break; | |
180 | } | |
181 | ||
182 | if (!dev) { | |
183 | printk(KERN_ERR "Device doesn't exist.\n"); | |
184 | return; | |
185 | } | |
186 | ||
187 | __w1_remove_master_device(dev); | |
188 | } | |
189 | ||
190 | EXPORT_SYMBOL(w1_add_master_device); | |
191 | EXPORT_SYMBOL(w1_remove_master_device); |