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22#include <linux/kernel.h>
23#include <linux/list.h>
24#include <linux/delay.h>
25#include <linux/kthread.h>
26#include <linux/slab.h>
27#include <linux/export.h>
28#include <linux/moduleparam.h>
29
30#include "w1.h"
31#include "w1_log.h"
32#include "w1_netlink.h"
33#include "w1_int.h"
34
35static int w1_search_count = -1;
36module_param_named(search_count, w1_search_count, int, 0);
37
38static int w1_enable_pullup = 1;
39module_param_named(enable_pullup, w1_enable_pullup, int, 0);
40
41static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
42 struct device_driver *driver,
43 struct device *device)
44{
45 struct w1_master *dev;
46 int err;
47
48
49
50
51 dev = kzalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL);
52 if (!dev) {
53 printk(KERN_ERR
54 "Failed to allocate %zd bytes for new w1 device.\n",
55 sizeof(struct w1_master));
56 return NULL;
57 }
58
59
60 dev->bus_master = (struct w1_bus_master *)(dev + 1);
61
62 dev->owner = THIS_MODULE;
63 dev->max_slave_count = slave_count;
64 dev->slave_count = 0;
65 dev->attempts = 0;
66 dev->initialized = 0;
67 dev->id = id;
68 dev->slave_ttl = slave_ttl;
69 dev->search_count = w1_search_count;
70 dev->enable_pullup = w1_enable_pullup;
71
72
73
74
75 atomic_set(&dev->refcnt, 2);
76
77 INIT_LIST_HEAD(&dev->slist);
78 INIT_LIST_HEAD(&dev->async_list);
79 mutex_init(&dev->mutex);
80 mutex_init(&dev->bus_mutex);
81 mutex_init(&dev->list_mutex);
82
83 memcpy(&dev->dev, device, sizeof(struct device));
84 dev_set_name(&dev->dev, "w1_bus_master%u", dev->id);
85 snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id);
86 dev->dev.init_name = dev->name;
87
88 dev->driver = driver;
89
90 dev->seq = 1;
91
92 err = device_register(&dev->dev);
93 if (err) {
94 printk(KERN_ERR "Failed to register master device. err=%d\n", err);
95 memset(dev, 0, sizeof(struct w1_master));
96 kfree(dev);
97 dev = NULL;
98 }
99
100 return dev;
101}
102
103static void w1_free_dev(struct w1_master *dev)
104{
105 device_unregister(&dev->dev);
106}
107
108
109
110
111
112int w1_add_master_device(struct w1_bus_master *master)
113{
114 struct w1_master *dev, *entry;
115 int retval = 0;
116 struct w1_netlink_msg msg;
117 int id, found;
118
119
120 if (!(master->touch_bit && master->reset_bus) &&
121 !(master->write_bit && master->read_bit) &&
122 !(master->write_byte && master->read_byte && master->reset_bus)) {
123 printk(KERN_ERR "w1_add_master_device: invalid function set\n");
124 return(-EINVAL);
125 }
126
127
128 mutex_lock(&w1_mlock);
129
130 id = 0;
131 do {
132 ++id;
133 found = 0;
134 list_for_each_entry(entry, &w1_masters, w1_master_entry) {
135 if (entry->id == id) {
136 found = 1;
137 break;
138 }
139 }
140 } while (found);
141
142 dev = w1_alloc_dev(id, w1_max_slave_count, w1_max_slave_ttl,
143 &w1_master_driver, &w1_master_device);
144 if (!dev) {
145 mutex_unlock(&w1_mlock);
146 return -ENOMEM;
147 }
148
149 retval = w1_create_master_attributes(dev);
150 if (retval) {
151 mutex_unlock(&w1_mlock);
152 goto err_out_free_dev;
153 }
154
155 memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
156
157 dev->initialized = 1;
158
159 dev->thread = kthread_run(&w1_process, dev, "%s", dev->name);
160 if (IS_ERR(dev->thread)) {
161 retval = PTR_ERR(dev->thread);
162 dev_err(&dev->dev,
163 "Failed to create new kernel thread. err=%d\n",
164 retval);
165 mutex_unlock(&w1_mlock);
166 goto err_out_rm_attr;
167 }
168
169 list_add(&dev->w1_master_entry, &w1_masters);
170 mutex_unlock(&w1_mlock);
171
172 memset(&msg, 0, sizeof(msg));
173 msg.id.mst.id = dev->id;
174 msg.type = W1_MASTER_ADD;
175 w1_netlink_send(dev, &msg);
176
177 return 0;
178
179#if 0
180err_out_kill_thread:
181 set_bit(W1_ABORT_SEARCH, &dev->flags);
182 kthread_stop(dev->thread);
183#endif
184err_out_rm_attr:
185 w1_destroy_master_attributes(dev);
186err_out_free_dev:
187 w1_free_dev(dev);
188
189 return retval;
190}
191
192void __w1_remove_master_device(struct w1_master *dev)
193{
194 struct w1_netlink_msg msg;
195 struct w1_slave *sl, *sln;
196
197 mutex_lock(&w1_mlock);
198 list_del(&dev->w1_master_entry);
199 mutex_unlock(&w1_mlock);
200
201 set_bit(W1_ABORT_SEARCH, &dev->flags);
202 kthread_stop(dev->thread);
203
204 mutex_lock(&dev->mutex);
205 mutex_lock(&dev->list_mutex);
206 list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
207 mutex_unlock(&dev->list_mutex);
208 w1_slave_detach(sl);
209 mutex_lock(&dev->list_mutex);
210 }
211 w1_destroy_master_attributes(dev);
212 mutex_unlock(&dev->list_mutex);
213 mutex_unlock(&dev->mutex);
214 atomic_dec(&dev->refcnt);
215
216 while (atomic_read(&dev->refcnt)) {
217 dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n",
218 dev->name, atomic_read(&dev->refcnt));
219
220 if (msleep_interruptible(1000))
221 flush_signals(current);
222 w1_process_callbacks(dev);
223 }
224 w1_process_callbacks(dev);
225
226 memset(&msg, 0, sizeof(msg));
227 msg.id.mst.id = dev->id;
228 msg.type = W1_MASTER_REMOVE;
229 w1_netlink_send(dev, &msg);
230
231 w1_free_dev(dev);
232}
233
234
235
236
237
238void w1_remove_master_device(struct w1_bus_master *bm)
239{
240 struct w1_master *dev, *found = NULL;
241
242 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
243 if (!dev->initialized)
244 continue;
245
246 if (dev->bus_master->data == bm->data) {
247 found = dev;
248 break;
249 }
250 }
251
252 if (!found) {
253 printk(KERN_ERR "Device doesn't exist.\n");
254 return;
255 }
256
257 __w1_remove_master_device(found);
258}
259
260EXPORT_SYMBOL(w1_add_master_device);
261EXPORT_SYMBOL(w1_remove_master_device);
262