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" | |
70d484bf | 30 | #include "w1_int.h" |
1da177e4 LT |
31 | |
32 | static u32 w1_ids = 1; | |
33 | ||
7785925d EP |
34 | static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl, |
35 | struct device_driver *driver, | |
36 | struct device *device) | |
1da177e4 LT |
37 | { |
38 | struct w1_master *dev; | |
39 | int err; | |
40 | ||
41 | /* | |
42 | * We are in process context(kernel thread), so can sleep. | |
43 | */ | |
dd00cc48 | 44 | dev = kzalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL); |
1da177e4 LT |
45 | if (!dev) { |
46 | printk(KERN_ERR | |
47 | "Failed to allocate %zd bytes for new w1 device.\n", | |
48 | sizeof(struct w1_master)); | |
49 | return NULL; | |
50 | } | |
51 | ||
1da177e4 LT |
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) && | |
c1f858b7 EP |
102 | !(master->write_bit && master->read_bit) && |
103 | !(master->write_byte && master->read_byte && master->reset_bus)) { | |
6adf87bd EP |
104 | printk(KERN_ERR "w1_add_master_device: invalid function set\n"); |
105 | return(-EINVAL); | |
be57ce26 EP |
106 | } |
107 | ||
7f772ed8 | 108 | dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_master_driver, &w1_master_device); |
1da177e4 LT |
109 | if (!dev) |
110 | return -ENOMEM; | |
111 | ||
674a396c EP |
112 | dev->thread = kthread_run(&w1_process, dev, "%s", dev->name); |
113 | if (IS_ERR(dev->thread)) { | |
114 | retval = PTR_ERR(dev->thread); | |
1da177e4 LT |
115 | dev_err(&dev->dev, |
116 | "Failed to create new kernel thread. err=%d\n", | |
674a396c | 117 | retval); |
1da177e4 LT |
118 | goto err_out_free_dev; |
119 | } | |
120 | ||
121 | retval = w1_create_master_attributes(dev); | |
122 | if (retval) | |
123 | goto err_out_kill_thread; | |
124 | ||
125 | memcpy(dev->bus_master, master, sizeof(struct w1_bus_master)); | |
126 | ||
127 | dev->initialized = 1; | |
128 | ||
abd52a13 | 129 | mutex_lock(&w1_mlock); |
1da177e4 | 130 | list_add(&dev->w1_master_entry, &w1_masters); |
abd52a13 | 131 | mutex_unlock(&w1_mlock); |
1da177e4 | 132 | |
12003375 | 133 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 134 | msg.id.mst.id = dev->id; |
1da177e4 LT |
135 | msg.type = W1_MASTER_ADD; |
136 | w1_netlink_send(dev, &msg); | |
137 | ||
138 | return 0; | |
139 | ||
140 | err_out_kill_thread: | |
674a396c | 141 | kthread_stop(dev->thread); |
1da177e4 LT |
142 | err_out_free_dev: |
143 | w1_free_dev(dev); | |
144 | ||
145 | return retval; | |
146 | } | |
147 | ||
148 | void __w1_remove_master_device(struct w1_master *dev) | |
149 | { | |
1da177e4 LT |
150 | struct w1_netlink_msg msg; |
151 | ||
6adf87bd | 152 | set_bit(W1_MASTER_NEED_EXIT, &dev->flags); |
674a396c | 153 | kthread_stop(dev->thread); |
1da177e4 LT |
154 | |
155 | while (atomic_read(&dev->refcnt)) { | |
674a396c | 156 | dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n", |
1da177e4 LT |
157 | dev->name, atomic_read(&dev->refcnt)); |
158 | ||
159 | if (msleep_interruptible(1000)) | |
160 | flush_signals(current); | |
161 | } | |
162 | ||
12003375 | 163 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 164 | msg.id.mst.id = dev->id; |
1da177e4 LT |
165 | msg.type = W1_MASTER_REMOVE; |
166 | w1_netlink_send(dev, &msg); | |
167 | ||
168 | w1_free_dev(dev); | |
169 | } | |
170 | ||
171 | void w1_remove_master_device(struct w1_bus_master *bm) | |
172 | { | |
173 | struct w1_master *dev = NULL; | |
1da177e4 | 174 | |
7785925d | 175 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
1da177e4 LT |
176 | if (!dev->initialized) |
177 | continue; | |
178 | ||
179 | if (dev->bus_master->data == bm->data) | |
180 | break; | |
181 | } | |
182 | ||
183 | if (!dev) { | |
184 | printk(KERN_ERR "Device doesn't exist.\n"); | |
185 | return; | |
186 | } | |
187 | ||
188 | __w1_remove_master_device(dev); | |
189 | } | |
190 | ||
191 | EXPORT_SYMBOL(w1_add_master_device); | |
192 | EXPORT_SYMBOL(w1_remove_master_device); |