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 | ||
12003375 EP |
33 | extern struct device_driver w1_master_driver; |
34 | extern struct bus_type w1_bus_type; | |
35 | extern struct device w1_master_device; | |
36 | extern int w1_max_slave_count; | |
37 | extern int w1_max_slave_ttl; | |
38 | extern struct list_head w1_masters; | |
abd52a13 | 39 | extern struct mutex w1_mlock; |
12003375 EP |
40 | |
41 | extern int w1_process(void *); | |
42 | ||
7785925d EP |
43 | static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl, |
44 | struct device_driver *driver, | |
45 | struct device *device) | |
1da177e4 LT |
46 | { |
47 | struct w1_master *dev; | |
48 | int err; | |
49 | ||
50 | /* | |
51 | * We are in process context(kernel thread), so can sleep. | |
52 | */ | |
53 | dev = kmalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL); | |
54 | if (!dev) { | |
55 | printk(KERN_ERR | |
56 | "Failed to allocate %zd bytes for new w1 device.\n", | |
57 | sizeof(struct w1_master)); | |
58 | return NULL; | |
59 | } | |
60 | ||
61 | memset(dev, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master)); | |
62 | ||
63 | dev->bus_master = (struct w1_bus_master *)(dev + 1); | |
64 | ||
7785925d EP |
65 | dev->owner = THIS_MODULE; |
66 | dev->max_slave_count = slave_count; | |
67 | dev->slave_count = 0; | |
68 | dev->attempts = 0; | |
7785925d EP |
69 | dev->initialized = 0; |
70 | dev->id = id; | |
1da177e4 | 71 | dev->slave_ttl = slave_ttl; |
2a9d0c17 | 72 | dev->search_count = -1; /* continual scan */ |
1da177e4 LT |
73 | |
74 | atomic_set(&dev->refcnt, 2); | |
75 | ||
76 | INIT_LIST_HEAD(&dev->slist); | |
abd52a13 | 77 | mutex_init(&dev->mutex); |
1da177e4 | 78 | |
1da177e4 LT |
79 | memcpy(&dev->dev, device, sizeof(struct device)); |
80 | snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id), | |
81 | "w1_bus_master%u", dev->id); | |
82 | snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id); | |
83 | ||
84 | dev->driver = driver; | |
85 | ||
1da177e4 | 86 | dev->seq = 1; |
1da177e4 LT |
87 | |
88 | err = device_register(&dev->dev); | |
89 | if (err) { | |
90 | printk(KERN_ERR "Failed to register master device. err=%d\n", err); | |
1da177e4 LT |
91 | memset(dev, 0, sizeof(struct w1_master)); |
92 | kfree(dev); | |
93 | dev = NULL; | |
94 | } | |
95 | ||
96 | return dev; | |
97 | } | |
98 | ||
12003375 | 99 | void w1_free_dev(struct w1_master *dev) |
1da177e4 LT |
100 | { |
101 | device_unregister(&dev->dev); | |
1da177e4 LT |
102 | } |
103 | ||
104 | int w1_add_master_device(struct w1_bus_master *master) | |
105 | { | |
106 | struct w1_master *dev; | |
107 | int retval = 0; | |
108 | struct w1_netlink_msg msg; | |
109 | ||
be57ce26 EP |
110 | /* validate minimum functionality */ |
111 | if (!(master->touch_bit && master->reset_bus) && | |
6adf87bd EP |
112 | !(master->write_bit && master->read_bit)) { |
113 | printk(KERN_ERR "w1_add_master_device: invalid function set\n"); | |
114 | return(-EINVAL); | |
be57ce26 EP |
115 | } |
116 | ||
7f772ed8 | 117 | dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_master_driver, &w1_master_device); |
1da177e4 LT |
118 | if (!dev) |
119 | return -ENOMEM; | |
120 | ||
674a396c EP |
121 | dev->thread = kthread_run(&w1_process, dev, "%s", dev->name); |
122 | if (IS_ERR(dev->thread)) { | |
123 | retval = PTR_ERR(dev->thread); | |
1da177e4 LT |
124 | dev_err(&dev->dev, |
125 | "Failed to create new kernel thread. err=%d\n", | |
674a396c | 126 | retval); |
1da177e4 LT |
127 | goto err_out_free_dev; |
128 | } | |
129 | ||
130 | retval = w1_create_master_attributes(dev); | |
131 | if (retval) | |
132 | goto err_out_kill_thread; | |
133 | ||
134 | memcpy(dev->bus_master, master, sizeof(struct w1_bus_master)); | |
135 | ||
136 | dev->initialized = 1; | |
137 | ||
abd52a13 | 138 | mutex_lock(&w1_mlock); |
1da177e4 | 139 | list_add(&dev->w1_master_entry, &w1_masters); |
abd52a13 | 140 | mutex_unlock(&w1_mlock); |
1da177e4 | 141 | |
12003375 | 142 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 143 | msg.id.mst.id = dev->id; |
1da177e4 LT |
144 | msg.type = W1_MASTER_ADD; |
145 | w1_netlink_send(dev, &msg); | |
146 | ||
147 | return 0; | |
148 | ||
149 | err_out_kill_thread: | |
674a396c | 150 | kthread_stop(dev->thread); |
1da177e4 LT |
151 | err_out_free_dev: |
152 | w1_free_dev(dev); | |
153 | ||
154 | return retval; | |
155 | } | |
156 | ||
157 | void __w1_remove_master_device(struct w1_master *dev) | |
158 | { | |
1da177e4 LT |
159 | struct w1_netlink_msg msg; |
160 | ||
6adf87bd | 161 | set_bit(W1_MASTER_NEED_EXIT, &dev->flags); |
674a396c | 162 | kthread_stop(dev->thread); |
1da177e4 LT |
163 | |
164 | while (atomic_read(&dev->refcnt)) { | |
674a396c | 165 | dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n", |
1da177e4 LT |
166 | dev->name, atomic_read(&dev->refcnt)); |
167 | ||
168 | if (msleep_interruptible(1000)) | |
169 | flush_signals(current); | |
170 | } | |
171 | ||
12003375 | 172 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 173 | msg.id.mst.id = dev->id; |
1da177e4 LT |
174 | msg.type = W1_MASTER_REMOVE; |
175 | w1_netlink_send(dev, &msg); | |
176 | ||
177 | w1_free_dev(dev); | |
178 | } | |
179 | ||
180 | void w1_remove_master_device(struct w1_bus_master *bm) | |
181 | { | |
182 | struct w1_master *dev = NULL; | |
1da177e4 | 183 | |
7785925d | 184 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
1da177e4 LT |
185 | if (!dev->initialized) |
186 | continue; | |
187 | ||
188 | if (dev->bus_master->data == bm->data) | |
189 | break; | |
190 | } | |
191 | ||
192 | if (!dev) { | |
193 | printk(KERN_ERR "Device doesn't exist.\n"); | |
194 | return; | |
195 | } | |
196 | ||
197 | __w1_remove_master_device(dev); | |
198 | } | |
199 | ||
200 | EXPORT_SYMBOL(w1_add_master_device); | |
201 | EXPORT_SYMBOL(w1_remove_master_device); |