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Commit | Line | Data |
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1da177e4 | 1 | /* |
7785925d | 2 | * w1.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/delay.h> | |
23 | #include <linux/kernel.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/moduleparam.h> | |
26 | #include <linux/list.h> | |
27 | #include <linux/interrupt.h> | |
28 | #include <linux/spinlock.h> | |
29 | #include <linux/timer.h> | |
30 | #include <linux/device.h> | |
31 | #include <linux/slab.h> | |
32 | #include <linux/sched.h> | |
33 | ||
34 | #include <asm/atomic.h> | |
35 | ||
36 | #include "w1.h" | |
37 | #include "w1_io.h" | |
38 | #include "w1_log.h" | |
39 | #include "w1_int.h" | |
40 | #include "w1_family.h" | |
41 | #include "w1_netlink.h" | |
42 | ||
43 | MODULE_LICENSE("GPL"); | |
44 | MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>"); | |
45 | MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol."); | |
46 | ||
47 | static int w1_timeout = 10; | |
48 | int w1_max_slave_count = 10; | |
49 | int w1_max_slave_ttl = 10; | |
50 | ||
51 | module_param_named(timeout, w1_timeout, int, 0); | |
52 | module_param_named(max_slave_count, w1_max_slave_count, int, 0); | |
53 | module_param_named(slave_ttl, w1_max_slave_ttl, int, 0); | |
54 | ||
55 | DEFINE_SPINLOCK(w1_mlock); | |
56 | LIST_HEAD(w1_masters); | |
57 | ||
58 | static pid_t control_thread; | |
59 | static int control_needs_exit; | |
60 | static DECLARE_COMPLETION(w1_control_complete); | |
61 | ||
99c5bfe9 EP |
62 | /* stuff for the default family */ |
63 | static ssize_t w1_famdefault_read_name(struct device *dev, struct device_attribute *attr, char *buf) | |
64 | { | |
65 | struct w1_slave *sl = container_of(dev, struct w1_slave, dev); | |
66 | return(sprintf(buf, "%s\n", sl->name)); | |
67 | } | |
68 | static struct w1_family_ops w1_default_fops = { | |
69 | .rname = &w1_famdefault_read_name, | |
70 | }; | |
71 | static struct w1_family w1_default_family = { | |
72 | .fops = &w1_default_fops, | |
73 | }; | |
74 | ||
1da177e4 LT |
75 | static int w1_master_match(struct device *dev, struct device_driver *drv) |
76 | { | |
77 | return 1; | |
78 | } | |
79 | ||
80 | static int w1_master_probe(struct device *dev) | |
81 | { | |
82 | return -ENODEV; | |
83 | } | |
84 | ||
85 | static int w1_master_remove(struct device *dev) | |
86 | { | |
87 | return 0; | |
88 | } | |
89 | ||
90 | static void w1_master_release(struct device *dev) | |
91 | { | |
db2d0008 | 92 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 LT |
93 | complete(&md->dev_released); |
94 | } | |
95 | ||
96 | static void w1_slave_release(struct device *dev) | |
97 | { | |
db2d0008 | 98 | struct w1_slave *sl = dev_to_w1_slave(dev); |
1da177e4 LT |
99 | complete(&sl->dev_released); |
100 | } | |
101 | ||
060b8845 | 102 | static ssize_t w1_default_read_name(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
103 | { |
104 | return sprintf(buf, "No family registered.\n"); | |
105 | } | |
106 | ||
107 | static ssize_t w1_default_read_bin(struct kobject *kobj, char *buf, loff_t off, | |
108 | size_t count) | |
109 | { | |
110 | return sprintf(buf, "No family registered.\n"); | |
111 | } | |
112 | ||
7785925d EP |
113 | static struct device_attribute w1_slave_attribute = |
114 | __ATTR(name, S_IRUGO, w1_default_read_name, NULL); | |
115 | ||
7785925d EP |
116 | static struct bin_attribute w1_slave_bin_attribute = { |
117 | .attr = { | |
118 | .name = "w1_slave", | |
119 | .mode = S_IRUGO, | |
120 | .owner = THIS_MODULE, | |
121 | }, | |
122 | .size = W1_SLAVE_DATA_SIZE, | |
123 | .read = &w1_default_read_bin, | |
124 | }; | |
125 | ||
7f772ed8 | 126 | static int w1_hotplug(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size); |
7785925d | 127 | |
1da177e4 LT |
128 | static struct bus_type w1_bus_type = { |
129 | .name = "w1", | |
130 | .match = w1_master_match, | |
7f772ed8 | 131 | .hotplug = w1_hotplug, |
1da177e4 LT |
132 | }; |
133 | ||
7f772ed8 EP |
134 | struct device_driver w1_master_driver = { |
135 | .name = "w1_master_driver", | |
1da177e4 LT |
136 | .bus = &w1_bus_type, |
137 | .probe = w1_master_probe, | |
138 | .remove = w1_master_remove, | |
139 | }; | |
140 | ||
7f772ed8 | 141 | struct device w1_master_device = { |
1da177e4 LT |
142 | .parent = NULL, |
143 | .bus = &w1_bus_type, | |
144 | .bus_id = "w1 bus master", | |
7f772ed8 | 145 | .driver = &w1_master_driver, |
1da177e4 LT |
146 | .release = &w1_master_release |
147 | }; | |
148 | ||
7f772ed8 EP |
149 | struct device_driver w1_slave_driver = { |
150 | .name = "w1_slave_driver", | |
151 | .bus = &w1_bus_type, | |
152 | }; | |
153 | ||
154 | struct device w1_slave_device = { | |
155 | .parent = NULL, | |
156 | .bus = &w1_bus_type, | |
157 | .bus_id = "w1 bus slave", | |
158 | .driver = &w1_slave_driver, | |
159 | }; | |
160 | ||
060b8845 | 161 | static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 162 | { |
db2d0008 | 163 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 164 | ssize_t count; |
7785925d | 165 | |
1da177e4 LT |
166 | if (down_interruptible (&md->mutex)) |
167 | return -EBUSY; | |
168 | ||
169 | count = sprintf(buf, "%s\n", md->name); | |
7785925d | 170 | |
1da177e4 LT |
171 | up(&md->mutex); |
172 | ||
173 | return count; | |
174 | } | |
175 | ||
2a9d0c17 EP |
176 | static ssize_t w1_master_attribute_store_search(struct device * dev, |
177 | struct device_attribute *attr, | |
178 | const char * buf, size_t count) | |
179 | { | |
db2d0008 | 180 | struct w1_master *md = dev_to_w1_master(dev); |
2a9d0c17 EP |
181 | |
182 | if (down_interruptible (&md->mutex)) | |
183 | return -EBUSY; | |
184 | ||
185 | md->search_count = simple_strtol(buf, NULL, 0); | |
186 | ||
187 | up(&md->mutex); | |
188 | ||
189 | return count; | |
190 | } | |
191 | ||
192 | static ssize_t w1_master_attribute_show_search(struct device *dev, | |
193 | struct device_attribute *attr, | |
194 | char *buf) | |
195 | { | |
db2d0008 | 196 | struct w1_master *md = dev_to_w1_master(dev); |
2a9d0c17 EP |
197 | ssize_t count; |
198 | ||
199 | if (down_interruptible (&md->mutex)) | |
200 | return -EBUSY; | |
201 | ||
202 | count = sprintf(buf, "%d\n", md->search_count); | |
203 | ||
204 | up(&md->mutex); | |
205 | ||
206 | return count; | |
207 | } | |
208 | ||
060b8845 | 209 | static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 210 | { |
db2d0008 | 211 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 212 | ssize_t count; |
7785925d | 213 | |
1da177e4 LT |
214 | if (down_interruptible(&md->mutex)) |
215 | return -EBUSY; | |
216 | ||
217 | count = sprintf(buf, "0x%p\n", md->bus_master); | |
7785925d | 218 | |
1da177e4 LT |
219 | up(&md->mutex); |
220 | return count; | |
221 | } | |
222 | ||
060b8845 | 223 | static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
224 | { |
225 | ssize_t count; | |
226 | count = sprintf(buf, "%d\n", w1_timeout); | |
227 | return count; | |
228 | } | |
229 | ||
060b8845 | 230 | static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 231 | { |
db2d0008 | 232 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 233 | ssize_t count; |
7785925d | 234 | |
1da177e4 LT |
235 | if (down_interruptible(&md->mutex)) |
236 | return -EBUSY; | |
237 | ||
238 | count = sprintf(buf, "%d\n", md->max_slave_count); | |
7785925d | 239 | |
1da177e4 LT |
240 | up(&md->mutex); |
241 | return count; | |
242 | } | |
243 | ||
060b8845 | 244 | static ssize_t w1_master_attribute_show_attempts(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 245 | { |
db2d0008 | 246 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 247 | ssize_t count; |
7785925d | 248 | |
1da177e4 LT |
249 | if (down_interruptible(&md->mutex)) |
250 | return -EBUSY; | |
251 | ||
252 | count = sprintf(buf, "%lu\n", md->attempts); | |
7785925d | 253 | |
1da177e4 LT |
254 | up(&md->mutex); |
255 | return count; | |
256 | } | |
257 | ||
060b8845 | 258 | static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 259 | { |
db2d0008 | 260 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 261 | ssize_t count; |
7785925d | 262 | |
1da177e4 LT |
263 | if (down_interruptible(&md->mutex)) |
264 | return -EBUSY; | |
265 | ||
266 | count = sprintf(buf, "%d\n", md->slave_count); | |
7785925d | 267 | |
1da177e4 LT |
268 | up(&md->mutex); |
269 | return count; | |
270 | } | |
271 | ||
060b8845 | 272 | static ssize_t w1_master_attribute_show_slaves(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 273 | { |
db2d0008 | 274 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 LT |
275 | int c = PAGE_SIZE; |
276 | ||
277 | if (down_interruptible(&md->mutex)) | |
278 | return -EBUSY; | |
279 | ||
280 | if (md->slave_count == 0) | |
281 | c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n"); | |
282 | else { | |
283 | struct list_head *ent, *n; | |
284 | struct w1_slave *sl; | |
285 | ||
286 | list_for_each_safe(ent, n, &md->slist) { | |
287 | sl = list_entry(ent, struct w1_slave, w1_slave_entry); | |
288 | ||
7785925d | 289 | c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name); |
1da177e4 LT |
290 | } |
291 | } | |
292 | ||
293 | up(&md->mutex); | |
294 | ||
295 | return PAGE_SIZE - c; | |
296 | } | |
297 | ||
7785925d EP |
298 | #define W1_MASTER_ATTR_RO(_name, _mode) \ |
299 | struct device_attribute w1_master_attribute_##_name = \ | |
300 | __ATTR(w1_master_##_name, _mode, \ | |
301 | w1_master_attribute_show_##_name, NULL) | |
302 | ||
2a9d0c17 EP |
303 | #define W1_MASTER_ATTR_RW(_name, _mode) \ |
304 | struct device_attribute w1_master_attribute_##_name = \ | |
305 | __ATTR(w1_master_##_name, _mode, \ | |
306 | w1_master_attribute_show_##_name, \ | |
307 | w1_master_attribute_store_##_name) | |
308 | ||
7785925d EP |
309 | static W1_MASTER_ATTR_RO(name, S_IRUGO); |
310 | static W1_MASTER_ATTR_RO(slaves, S_IRUGO); | |
311 | static W1_MASTER_ATTR_RO(slave_count, S_IRUGO); | |
312 | static W1_MASTER_ATTR_RO(max_slave_count, S_IRUGO); | |
313 | static W1_MASTER_ATTR_RO(attempts, S_IRUGO); | |
314 | static W1_MASTER_ATTR_RO(timeout, S_IRUGO); | |
315 | static W1_MASTER_ATTR_RO(pointer, S_IRUGO); | |
2a9d0c17 | 316 | static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUGO); |
7785925d EP |
317 | |
318 | static struct attribute *w1_master_default_attrs[] = { | |
319 | &w1_master_attribute_name.attr, | |
320 | &w1_master_attribute_slaves.attr, | |
321 | &w1_master_attribute_slave_count.attr, | |
322 | &w1_master_attribute_max_slave_count.attr, | |
323 | &w1_master_attribute_attempts.attr, | |
324 | &w1_master_attribute_timeout.attr, | |
325 | &w1_master_attribute_pointer.attr, | |
2a9d0c17 | 326 | &w1_master_attribute_search.attr, |
7785925d | 327 | NULL |
1da177e4 LT |
328 | }; |
329 | ||
7785925d EP |
330 | static struct attribute_group w1_master_defattr_group = { |
331 | .attrs = w1_master_default_attrs, | |
1da177e4 LT |
332 | }; |
333 | ||
7785925d EP |
334 | int w1_create_master_attributes(struct w1_master *master) |
335 | { | |
336 | return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group); | |
337 | } | |
338 | ||
339 | void w1_destroy_master_attributes(struct w1_master *master) | |
340 | { | |
341 | sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group); | |
342 | } | |
343 | ||
7f772ed8 EP |
344 | #ifdef CONFIG_HOTPLUG |
345 | static int w1_hotplug(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size) | |
346 | { | |
347 | struct w1_master *md = NULL; | |
348 | struct w1_slave *sl = NULL; | |
349 | char *event_owner, *name; | |
350 | int err, cur_index=0, cur_len=0; | |
351 | ||
352 | if (dev->driver == &w1_master_driver) { | |
353 | md = container_of(dev, struct w1_master, dev); | |
354 | event_owner = "master"; | |
355 | name = md->name; | |
356 | } else if (dev->driver == &w1_slave_driver) { | |
357 | sl = container_of(dev, struct w1_slave, dev); | |
358 | event_owner = "slave"; | |
359 | name = sl->name; | |
360 | } else { | |
361 | dev_dbg(dev, "Unknown hotplug event.\n"); | |
362 | return -EINVAL; | |
363 | } | |
364 | ||
365 | dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n", event_owner, name, dev->bus_id); | |
366 | ||
367 | if (dev->driver != &w1_slave_driver || !sl) | |
368 | return 0; | |
369 | ||
370 | err = add_hotplug_env_var(envp, num_envp, &cur_index, buffer, buffer_size, &cur_len, "W1_FID=%02X", sl->reg_num.family); | |
371 | if (err) | |
372 | return err; | |
373 | ||
5e8eb850 | 374 | err = add_hotplug_env_var(envp, num_envp, &cur_index, buffer, buffer_size, &cur_len, "W1_SLAVE_ID=%024LX", (u64)sl->reg_num.id); |
7f772ed8 EP |
375 | if (err) |
376 | return err; | |
377 | ||
378 | return 0; | |
379 | }; | |
380 | #else | |
381 | static int w1_hotplug(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size) | |
382 | { | |
383 | return 0; | |
384 | } | |
385 | #endif | |
386 | ||
1da177e4 LT |
387 | static int __w1_attach_slave_device(struct w1_slave *sl) |
388 | { | |
389 | int err; | |
390 | ||
391 | sl->dev.parent = &sl->master->dev; | |
7f772ed8 | 392 | sl->dev.driver = &w1_slave_driver; |
1da177e4 LT |
393 | sl->dev.bus = &w1_bus_type; |
394 | sl->dev.release = &w1_slave_release; | |
395 | ||
396 | snprintf(&sl->dev.bus_id[0], sizeof(sl->dev.bus_id), | |
6b729861 EP |
397 | "%02x-%012llx", |
398 | (unsigned int) sl->reg_num.family, | |
399 | (unsigned long long) sl->reg_num.id); | |
400 | snprintf(&sl->name[0], sizeof(sl->name), | |
401 | "%02x-%012llx", | |
402 | (unsigned int) sl->reg_num.family, | |
403 | (unsigned long long) sl->reg_num.id); | |
1da177e4 LT |
404 | |
405 | dev_dbg(&sl->dev, "%s: registering %s.\n", __func__, | |
406 | &sl->dev.bus_id[0]); | |
407 | ||
408 | err = device_register(&sl->dev); | |
409 | if (err < 0) { | |
410 | dev_err(&sl->dev, | |
6b729861 EP |
411 | "Device registration [%s] failed. err=%d\n", |
412 | sl->dev.bus_id, err); | |
1da177e4 LT |
413 | return err; |
414 | } | |
415 | ||
416 | memcpy(&sl->attr_bin, &w1_slave_bin_attribute, sizeof(sl->attr_bin)); | |
417 | memcpy(&sl->attr_name, &w1_slave_attribute, sizeof(sl->attr_name)); | |
7785925d | 418 | |
1da177e4 LT |
419 | sl->attr_bin.read = sl->family->fops->rbin; |
420 | sl->attr_name.show = sl->family->fops->rname; | |
1da177e4 LT |
421 | |
422 | err = device_create_file(&sl->dev, &sl->attr_name); | |
423 | if (err < 0) { | |
424 | dev_err(&sl->dev, | |
6b729861 EP |
425 | "sysfs file creation for [%s] failed. err=%d\n", |
426 | sl->dev.bus_id, err); | |
1da177e4 LT |
427 | device_unregister(&sl->dev); |
428 | return err; | |
429 | } | |
430 | ||
99c5bfe9 EP |
431 | if ( sl->attr_bin.read ) { |
432 | err = sysfs_create_bin_file(&sl->dev.kobj, &sl->attr_bin); | |
433 | if (err < 0) { | |
434 | dev_err(&sl->dev, | |
435 | "sysfs file creation for [%s] failed. err=%d\n", | |
436 | sl->dev.bus_id, err); | |
437 | device_remove_file(&sl->dev, &sl->attr_name); | |
438 | device_unregister(&sl->dev); | |
439 | return err; | |
440 | } | |
1da177e4 LT |
441 | } |
442 | ||
443 | list_add_tail(&sl->w1_slave_entry, &sl->master->slist); | |
444 | ||
445 | return 0; | |
446 | } | |
447 | ||
448 | static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) | |
449 | { | |
450 | struct w1_slave *sl; | |
451 | struct w1_family *f; | |
452 | int err; | |
453 | struct w1_netlink_msg msg; | |
454 | ||
455 | sl = kmalloc(sizeof(struct w1_slave), GFP_KERNEL); | |
456 | if (!sl) { | |
457 | dev_err(&dev->dev, | |
458 | "%s: failed to allocate new slave device.\n", | |
459 | __func__); | |
460 | return -ENOMEM; | |
461 | } | |
462 | ||
463 | memset(sl, 0, sizeof(*sl)); | |
464 | ||
465 | sl->owner = THIS_MODULE; | |
466 | sl->master = dev; | |
467 | set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); | |
468 | ||
469 | memcpy(&sl->reg_num, rn, sizeof(sl->reg_num)); | |
470 | atomic_set(&sl->refcnt, 0); | |
471 | init_completion(&sl->dev_released); | |
472 | ||
473 | spin_lock(&w1_flock); | |
474 | f = w1_family_registered(rn->family); | |
475 | if (!f) { | |
99c5bfe9 | 476 | f= &w1_default_family; |
1da177e4 LT |
477 | dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n", |
478 | rn->family, rn->family, | |
479 | (unsigned long long)rn->id, rn->crc); | |
1da177e4 LT |
480 | } |
481 | __w1_family_get(f); | |
482 | spin_unlock(&w1_flock); | |
483 | ||
484 | sl->family = f; | |
485 | ||
486 | ||
487 | err = __w1_attach_slave_device(sl); | |
488 | if (err < 0) { | |
489 | dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__, | |
490 | sl->name); | |
491 | w1_family_put(sl->family); | |
492 | kfree(sl); | |
493 | return err; | |
494 | } | |
495 | ||
496 | sl->ttl = dev->slave_ttl; | |
497 | dev->slave_count++; | |
498 | ||
499 | memcpy(&msg.id.id, rn, sizeof(msg.id.id)); | |
500 | msg.type = W1_SLAVE_ADD; | |
501 | w1_netlink_send(dev, &msg); | |
502 | ||
503 | return 0; | |
504 | } | |
505 | ||
506 | static void w1_slave_detach(struct w1_slave *sl) | |
507 | { | |
508 | struct w1_netlink_msg msg; | |
7785925d | 509 | |
1da177e4 LT |
510 | dev_info(&sl->dev, "%s: detaching %s.\n", __func__, sl->name); |
511 | ||
512 | while (atomic_read(&sl->refcnt)) { | |
513 | printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n", | |
514 | sl->name, atomic_read(&sl->refcnt)); | |
515 | ||
516 | if (msleep_interruptible(1000)) | |
517 | flush_signals(current); | |
518 | } | |
519 | ||
99c5bfe9 EP |
520 | if ( sl->attr_bin.read ) { |
521 | sysfs_remove_bin_file (&sl->dev.kobj, &sl->attr_bin); | |
522 | } | |
1da177e4 | 523 | device_remove_file(&sl->dev, &sl->attr_name); |
1da177e4 LT |
524 | device_unregister(&sl->dev); |
525 | w1_family_put(sl->family); | |
526 | ||
6adf87bd EP |
527 | sl->master->slave_count--; |
528 | ||
1da177e4 LT |
529 | memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id)); |
530 | msg.type = W1_SLAVE_REMOVE; | |
531 | w1_netlink_send(sl->master, &msg); | |
532 | } | |
533 | ||
534 | static struct w1_master *w1_search_master(unsigned long data) | |
535 | { | |
536 | struct w1_master *dev; | |
537 | int found = 0; | |
7785925d EP |
538 | |
539 | spin_lock_bh(&w1_mlock); | |
1da177e4 LT |
540 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
541 | if (dev->bus_master->data == data) { | |
542 | found = 1; | |
543 | atomic_inc(&dev->refcnt); | |
544 | break; | |
545 | } | |
546 | } | |
7785925d | 547 | spin_unlock_bh(&w1_mlock); |
1da177e4 LT |
548 | |
549 | return (found)?dev:NULL; | |
550 | } | |
551 | ||
6adf87bd EP |
552 | void w1_reconnect_slaves(struct w1_family *f) |
553 | { | |
554 | struct w1_master *dev; | |
555 | ||
556 | spin_lock_bh(&w1_mlock); | |
557 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { | |
558 | dev_info(&dev->dev, "Reconnecting slaves in %s into new family %02x.\n", | |
559 | dev->name, f->fid); | |
560 | set_bit(W1_MASTER_NEED_RECONNECT, &dev->flags); | |
561 | } | |
562 | spin_unlock_bh(&w1_mlock); | |
563 | } | |
564 | ||
7785925d | 565 | static void w1_slave_found(unsigned long data, u64 rn) |
1da177e4 LT |
566 | { |
567 | int slave_count; | |
568 | struct w1_slave *sl; | |
569 | struct list_head *ent; | |
570 | struct w1_reg_num *tmp; | |
571 | int family_found = 0; | |
572 | struct w1_master *dev; | |
0e65f828 | 573 | u64 rn_le = cpu_to_le64(rn); |
1da177e4 LT |
574 | |
575 | dev = w1_search_master(data); | |
576 | if (!dev) { | |
577 | printk(KERN_ERR "Failed to find w1 master device for data %08lx, it is impossible.\n", | |
578 | data); | |
579 | return; | |
580 | } | |
7785925d | 581 | |
1da177e4 LT |
582 | tmp = (struct w1_reg_num *) &rn; |
583 | ||
584 | slave_count = 0; | |
585 | list_for_each(ent, &dev->slist) { | |
586 | ||
587 | sl = list_entry(ent, struct w1_slave, w1_slave_entry); | |
588 | ||
589 | if (sl->reg_num.family == tmp->family && | |
590 | sl->reg_num.id == tmp->id && | |
591 | sl->reg_num.crc == tmp->crc) { | |
592 | set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); | |
593 | break; | |
7785925d | 594 | } else if (sl->reg_num.family == tmp->family) { |
1da177e4 LT |
595 | family_found = 1; |
596 | break; | |
597 | } | |
598 | ||
599 | slave_count++; | |
600 | } | |
601 | ||
8523ff45 | 602 | if (slave_count == dev->slave_count && |
0e65f828 | 603 | rn && ((rn >> 56) & 0xff) == w1_calc_crc8((u8 *)&rn_le, 7)) { |
8523ff45 | 604 | w1_attach_slave_device(dev, tmp); |
1da177e4 | 605 | } |
7785925d | 606 | |
1da177e4 LT |
607 | atomic_dec(&dev->refcnt); |
608 | } | |
609 | ||
6b729861 EP |
610 | /** |
611 | * Performs a ROM Search & registers any devices found. | |
612 | * The 1-wire search is a simple binary tree search. | |
613 | * For each bit of the address, we read two bits and write one bit. | |
614 | * The bit written will put to sleep all devies that don't match that bit. | |
615 | * When the two reads differ, the direction choice is obvious. | |
616 | * When both bits are 0, we must choose a path to take. | |
617 | * When we can scan all 64 bits without having to choose a path, we are done. | |
618 | * | |
619 | * See "Application note 187 1-wire search algorithm" at www.maxim-ic.com | |
620 | * | |
621 | * @dev The master device to search | |
622 | * @cb Function to call when a device is found | |
623 | */ | |
624 | void w1_search(struct w1_master *dev, w1_slave_found_callback cb) | |
1da177e4 | 625 | { |
6b729861 EP |
626 | u64 last_rn, rn, tmp64; |
627 | int i, slave_count = 0; | |
628 | int last_zero, last_device; | |
629 | int search_bit, desc_bit; | |
630 | u8 triplet_ret = 0; | |
1da177e4 | 631 | |
6b729861 EP |
632 | search_bit = 0; |
633 | rn = last_rn = 0; | |
634 | last_device = 0; | |
635 | last_zero = -1; | |
1da177e4 LT |
636 | |
637 | desc_bit = 64; | |
638 | ||
6b729861 EP |
639 | while ( !last_device && (slave_count++ < dev->max_slave_count) ) { |
640 | last_rn = rn; | |
1da177e4 LT |
641 | rn = 0; |
642 | ||
1da177e4 LT |
643 | /* |
644 | * Reset bus and all 1-wire device state machines | |
645 | * so they can respond to our requests. | |
646 | * | |
647 | * Return 0 - device(s) present, 1 - no devices present. | |
648 | */ | |
649 | if (w1_reset_bus(dev)) { | |
2da5bf80 | 650 | dev_dbg(&dev->dev, "No devices present on the wire.\n"); |
1da177e4 LT |
651 | break; |
652 | } | |
653 | ||
6b729861 | 654 | /* Start the search */ |
1da177e4 LT |
655 | w1_write_8(dev, W1_SEARCH); |
656 | for (i = 0; i < 64; ++i) { | |
6b729861 EP |
657 | /* Determine the direction/search bit */ |
658 | if (i == desc_bit) | |
659 | search_bit = 1; /* took the 0 path last time, so take the 1 path */ | |
660 | else if (i > desc_bit) | |
661 | search_bit = 0; /* take the 0 path on the next branch */ | |
1da177e4 | 662 | else |
6b729861 | 663 | search_bit = ((last_rn >> i) & 0x1); |
1da177e4 | 664 | |
6b729861 EP |
665 | /** Read two bits and write one bit */ |
666 | triplet_ret = w1_triplet(dev, search_bit); | |
667 | ||
668 | /* quit if no device responded */ | |
669 | if ( (triplet_ret & 0x03) == 0x03 ) | |
670 | break; | |
1da177e4 | 671 | |
6b729861 EP |
672 | /* If both directions were valid, and we took the 0 path... */ |
673 | if (triplet_ret == 0) | |
674 | last_zero = i; | |
1da177e4 | 675 | |
6b729861 EP |
676 | /* extract the direction taken & update the device number */ |
677 | tmp64 = (triplet_ret >> 2); | |
678 | rn |= (tmp64 << i); | |
679 | } | |
7785925d | 680 | |
6b729861 EP |
681 | if ( (triplet_ret & 0x03) != 0x03 ) { |
682 | if ( (desc_bit == last_zero) || (last_zero < 0)) | |
683 | last_device = 1; | |
684 | desc_bit = last_zero; | |
685 | cb(dev->bus_master->data, rn); | |
686 | } | |
1da177e4 LT |
687 | } |
688 | } | |
689 | ||
7785925d | 690 | static int w1_control(void *data) |
1da177e4 | 691 | { |
7785925d EP |
692 | struct w1_slave *sl, *sln; |
693 | struct w1_master *dev, *n; | |
1da177e4 LT |
694 | int err, have_to_wait = 0; |
695 | ||
696 | daemonize("w1_control"); | |
697 | allow_signal(SIGTERM); | |
698 | ||
699 | while (!control_needs_exit || have_to_wait) { | |
700 | have_to_wait = 0; | |
701 | ||
3e1d1d28 | 702 | try_to_freeze(); |
1da177e4 LT |
703 | msleep_interruptible(w1_timeout * 1000); |
704 | ||
705 | if (signal_pending(current)) | |
706 | flush_signals(current); | |
707 | ||
7785925d | 708 | list_for_each_entry_safe(dev, n, &w1_masters, w1_master_entry) { |
6adf87bd | 709 | if (!control_needs_exit && !dev->flags) |
1da177e4 LT |
710 | continue; |
711 | /* | |
712 | * Little race: we can create thread but not set the flag. | |
713 | * Get a chance for external process to set flag up. | |
714 | */ | |
715 | if (!dev->initialized) { | |
716 | have_to_wait = 1; | |
717 | continue; | |
718 | } | |
719 | ||
1da177e4 | 720 | if (control_needs_exit) { |
6adf87bd | 721 | set_bit(W1_MASTER_NEED_EXIT, &dev->flags); |
1da177e4 LT |
722 | |
723 | err = kill_proc(dev->kpid, SIGTERM, 1); | |
724 | if (err) | |
725 | dev_err(&dev->dev, | |
726 | "Failed to send signal to w1 kernel thread %d.\n", | |
727 | dev->kpid); | |
728 | } | |
729 | ||
6adf87bd EP |
730 | if (test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) { |
731 | wait_for_completion(&dev->dev_exited); | |
732 | spin_lock_bh(&w1_mlock); | |
733 | list_del(&dev->w1_master_entry); | |
734 | spin_unlock_bh(&w1_mlock); | |
735 | ||
736 | list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { | |
737 | list_del(&sl->w1_slave_entry); | |
738 | ||
739 | w1_slave_detach(sl); | |
740 | kfree(sl); | |
741 | } | |
742 | w1_destroy_master_attributes(dev); | |
743 | atomic_dec(&dev->refcnt); | |
744 | continue; | |
745 | } | |
746 | ||
747 | if (test_bit(W1_MASTER_NEED_RECONNECT, &dev->flags)) { | |
748 | dev_info(&dev->dev, "Reconnecting slaves in device %s.\n", dev->name); | |
749 | down(&dev->mutex); | |
750 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) { | |
751 | if (sl->family->fid == W1_FAMILY_DEFAULT) { | |
752 | struct w1_reg_num rn; | |
753 | list_del(&sl->w1_slave_entry); | |
754 | w1_slave_detach(sl); | |
755 | ||
756 | memcpy(&rn, &sl->reg_num, sizeof(rn)); | |
1da177e4 | 757 | |
6adf87bd | 758 | kfree(sl); |
1da177e4 | 759 | |
6adf87bd EP |
760 | w1_attach_slave_device(dev, &rn); |
761 | } | |
762 | } | |
763 | clear_bit(W1_MASTER_NEED_RECONNECT, &dev->flags); | |
764 | up(&dev->mutex); | |
1da177e4 | 765 | } |
1da177e4 LT |
766 | } |
767 | } | |
768 | ||
769 | complete_and_exit(&w1_control_complete, 0); | |
770 | } | |
771 | ||
772 | int w1_process(void *data) | |
773 | { | |
774 | struct w1_master *dev = (struct w1_master *) data; | |
7785925d | 775 | struct w1_slave *sl, *sln; |
1da177e4 LT |
776 | |
777 | daemonize("%s", dev->name); | |
778 | allow_signal(SIGTERM); | |
779 | ||
6adf87bd | 780 | while (!test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) { |
3e1d1d28 | 781 | try_to_freeze(); |
1da177e4 LT |
782 | msleep_interruptible(w1_timeout * 1000); |
783 | ||
784 | if (signal_pending(current)) | |
785 | flush_signals(current); | |
786 | ||
6adf87bd | 787 | if (test_bit(W1_MASTER_NEED_EXIT, &dev->flags)) |
1da177e4 LT |
788 | break; |
789 | ||
790 | if (!dev->initialized) | |
791 | continue; | |
792 | ||
2a9d0c17 EP |
793 | if (dev->search_count == 0) |
794 | continue; | |
795 | ||
1da177e4 LT |
796 | if (down_interruptible(&dev->mutex)) |
797 | continue; | |
798 | ||
7785925d | 799 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) |
2a9d0c17 | 800 | clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); |
1da177e4 | 801 | |
7785925d | 802 | w1_search_devices(dev, w1_slave_found); |
1da177e4 | 803 | |
7785925d EP |
804 | list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { |
805 | if (!test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl) { | |
1da177e4 LT |
806 | list_del (&sl->w1_slave_entry); |
807 | ||
808 | w1_slave_detach (sl); | |
809 | kfree (sl); | |
810 | ||
811 | dev->slave_count--; | |
7785925d | 812 | } else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags)) |
1da177e4 LT |
813 | sl->ttl = dev->slave_ttl; |
814 | } | |
2a9d0c17 EP |
815 | |
816 | if (dev->search_count > 0) | |
817 | dev->search_count--; | |
818 | ||
1da177e4 LT |
819 | up(&dev->mutex); |
820 | } | |
821 | ||
822 | atomic_dec(&dev->refcnt); | |
823 | complete_and_exit(&dev->dev_exited, 0); | |
824 | ||
825 | return 0; | |
826 | } | |
827 | ||
7785925d | 828 | static int w1_init(void) |
1da177e4 LT |
829 | { |
830 | int retval; | |
831 | ||
832 | printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n"); | |
833 | ||
834 | retval = bus_register(&w1_bus_type); | |
835 | if (retval) { | |
836 | printk(KERN_ERR "Failed to register bus. err=%d.\n", retval); | |
837 | goto err_out_exit_init; | |
838 | } | |
839 | ||
7f772ed8 | 840 | retval = driver_register(&w1_master_driver); |
1da177e4 LT |
841 | if (retval) { |
842 | printk(KERN_ERR | |
843 | "Failed to register master driver. err=%d.\n", | |
844 | retval); | |
845 | goto err_out_bus_unregister; | |
846 | } | |
847 | ||
7f772ed8 EP |
848 | retval = driver_register(&w1_slave_driver); |
849 | if (retval) { | |
850 | printk(KERN_ERR | |
851 | "Failed to register master driver. err=%d.\n", | |
852 | retval); | |
853 | goto err_out_master_unregister; | |
854 | } | |
855 | ||
1da177e4 LT |
856 | control_thread = kernel_thread(&w1_control, NULL, 0); |
857 | if (control_thread < 0) { | |
858 | printk(KERN_ERR "Failed to create control thread. err=%d\n", | |
859 | control_thread); | |
860 | retval = control_thread; | |
7f772ed8 | 861 | goto err_out_slave_unregister; |
1da177e4 LT |
862 | } |
863 | ||
864 | return 0; | |
865 | ||
7f772ed8 EP |
866 | err_out_slave_unregister: |
867 | driver_unregister(&w1_slave_driver); | |
868 | ||
869 | err_out_master_unregister: | |
870 | driver_unregister(&w1_master_driver); | |
1da177e4 LT |
871 | |
872 | err_out_bus_unregister: | |
873 | bus_unregister(&w1_bus_type); | |
874 | ||
875 | err_out_exit_init: | |
876 | return retval; | |
877 | } | |
878 | ||
7785925d | 879 | static void w1_fini(void) |
1da177e4 LT |
880 | { |
881 | struct w1_master *dev; | |
1da177e4 | 882 | |
7785925d | 883 | list_for_each_entry(dev, &w1_masters, w1_master_entry) |
1da177e4 | 884 | __w1_remove_master_device(dev); |
1da177e4 LT |
885 | |
886 | control_needs_exit = 1; | |
1da177e4 LT |
887 | wait_for_completion(&w1_control_complete); |
888 | ||
7f772ed8 EP |
889 | driver_unregister(&w1_slave_driver); |
890 | driver_unregister(&w1_master_driver); | |
1da177e4 LT |
891 | bus_unregister(&w1_bus_type); |
892 | } | |
893 | ||
894 | module_init(w1_init); | |
895 | module_exit(w1_fini); |