blob: 8d7821899cc10440137299c7254ee4750c416d8d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * w1.c
3 *
4 * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
5 *
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
43MODULE_LICENSE("GPL");
44MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
45MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");
46
47static int w1_timeout = 10;
48int w1_max_slave_count = 10;
49int w1_max_slave_ttl = 10;
50
51module_param_named(timeout, w1_timeout, int, 0);
52module_param_named(max_slave_count, w1_max_slave_count, int, 0);
53module_param_named(slave_ttl, w1_max_slave_ttl, int, 0);
54
55DEFINE_SPINLOCK(w1_mlock);
56LIST_HEAD(w1_masters);
57
58static pid_t control_thread;
59static int control_needs_exit;
60static DECLARE_COMPLETION(w1_control_complete);
61
62static int w1_master_match(struct device *dev, struct device_driver *drv)
63{
64 return 1;
65}
66
67static int w1_master_probe(struct device *dev)
68{
69 return -ENODEV;
70}
71
72static int w1_master_remove(struct device *dev)
73{
74 return 0;
75}
76
77static void w1_master_release(struct device *dev)
78{
79 struct w1_master *md = container_of(dev, struct w1_master, dev);
80
81 complete(&md->dev_released);
82}
83
84static void w1_slave_release(struct device *dev)
85{
86 struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
87
88 complete(&sl->dev_released);
89}
90
91static ssize_t w1_default_read_name(struct device *dev, char *buf)
92{
93 return sprintf(buf, "No family registered.\n");
94}
95
96static ssize_t w1_default_read_bin(struct kobject *kobj, char *buf, loff_t off,
97 size_t count)
98{
99 return sprintf(buf, "No family registered.\n");
100}
101
102static struct bus_type w1_bus_type = {
103 .name = "w1",
104 .match = w1_master_match,
105};
106
107struct device_driver w1_driver = {
108 .name = "w1_driver",
109 .bus = &w1_bus_type,
110 .probe = w1_master_probe,
111 .remove = w1_master_remove,
112};
113
114struct device w1_device = {
115 .parent = NULL,
116 .bus = &w1_bus_type,
117 .bus_id = "w1 bus master",
118 .driver = &w1_driver,
119 .release = &w1_master_release
120};
121
122static struct device_attribute w1_slave_attribute = {
123 .attr = {
124 .name = "name",
125 .mode = S_IRUGO,
126 .owner = THIS_MODULE
127 },
128 .show = &w1_default_read_name,
129};
130
131static struct device_attribute w1_slave_attribute_val = {
132 .attr = {
133 .name = "value",
134 .mode = S_IRUGO,
135 .owner = THIS_MODULE
136 },
137 .show = &w1_default_read_name,
138};
139
140static ssize_t w1_master_attribute_show_name(struct device *dev, char *buf)
141{
142 struct w1_master *md = container_of (dev, struct w1_master, dev);
143 ssize_t count;
144
145 if (down_interruptible (&md->mutex))
146 return -EBUSY;
147
148 count = sprintf(buf, "%s\n", md->name);
149
150 up(&md->mutex);
151
152 return count;
153}
154
155static ssize_t w1_master_attribute_show_pointer(struct device *dev, char *buf)
156{
157 struct w1_master *md = container_of(dev, struct w1_master, dev);
158 ssize_t count;
159
160 if (down_interruptible(&md->mutex))
161 return -EBUSY;
162
163 count = sprintf(buf, "0x%p\n", md->bus_master);
164
165 up(&md->mutex);
166 return count;
167}
168
169static ssize_t w1_master_attribute_show_timeout(struct device *dev, char *buf)
170{
171 ssize_t count;
172 count = sprintf(buf, "%d\n", w1_timeout);
173 return count;
174}
175
176static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, char *buf)
177{
178 struct w1_master *md = container_of(dev, struct w1_master, dev);
179 ssize_t count;
180
181 if (down_interruptible(&md->mutex))
182 return -EBUSY;
183
184 count = sprintf(buf, "%d\n", md->max_slave_count);
185
186 up(&md->mutex);
187 return count;
188}
189
190static ssize_t w1_master_attribute_show_attempts(struct device *dev, char *buf)
191{
192 struct w1_master *md = container_of(dev, struct w1_master, dev);
193 ssize_t count;
194
195 if (down_interruptible(&md->mutex))
196 return -EBUSY;
197
198 count = sprintf(buf, "%lu\n", md->attempts);
199
200 up(&md->mutex);
201 return count;
202}
203
204static ssize_t w1_master_attribute_show_slave_count(struct device *dev, char *buf)
205{
206 struct w1_master *md = container_of(dev, struct w1_master, dev);
207 ssize_t count;
208
209 if (down_interruptible(&md->mutex))
210 return -EBUSY;
211
212 count = sprintf(buf, "%d\n", md->slave_count);
213
214 up(&md->mutex);
215 return count;
216}
217
218static ssize_t w1_master_attribute_show_slaves(struct device *dev, char *buf)
219
220{
221 struct w1_master *md = container_of(dev, struct w1_master, dev);
222 int c = PAGE_SIZE;
223
224 if (down_interruptible(&md->mutex))
225 return -EBUSY;
226
227 if (md->slave_count == 0)
228 c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
229 else {
230 struct list_head *ent, *n;
231 struct w1_slave *sl;
232
233 list_for_each_safe(ent, n, &md->slist) {
234 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
235
236 c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
237 }
238 }
239
240 up(&md->mutex);
241
242 return PAGE_SIZE - c;
243}
244
245static struct device_attribute w1_master_attribute_slaves = {
246 .attr = {
247 .name = "w1_master_slaves",
248 .mode = S_IRUGO,
249 .owner = THIS_MODULE,
250 },
251 .show = &w1_master_attribute_show_slaves,
252};
253static struct device_attribute w1_master_attribute_slave_count = {
254 .attr = {
255 .name = "w1_master_slave_count",
256 .mode = S_IRUGO,
257 .owner = THIS_MODULE
258 },
259 .show = &w1_master_attribute_show_slave_count,
260};
261static struct device_attribute w1_master_attribute_attempts = {
262 .attr = {
263 .name = "w1_master_attempts",
264 .mode = S_IRUGO,
265 .owner = THIS_MODULE
266 },
267 .show = &w1_master_attribute_show_attempts,
268};
269static struct device_attribute w1_master_attribute_max_slave_count = {
270 .attr = {
271 .name = "w1_master_max_slave_count",
272 .mode = S_IRUGO,
273 .owner = THIS_MODULE
274 },
275 .show = &w1_master_attribute_show_max_slave_count,
276};
277static struct device_attribute w1_master_attribute_timeout = {
278 .attr = {
279 .name = "w1_master_timeout",
280 .mode = S_IRUGO,
281 .owner = THIS_MODULE
282 },
283 .show = &w1_master_attribute_show_timeout,
284};
285static struct device_attribute w1_master_attribute_pointer = {
286 .attr = {
287 .name = "w1_master_pointer",
288 .mode = S_IRUGO,
289 .owner = THIS_MODULE
290 },
291 .show = &w1_master_attribute_show_pointer,
292};
293static struct device_attribute w1_master_attribute_name = {
294 .attr = {
295 .name = "w1_master_name",
296 .mode = S_IRUGO,
297 .owner = THIS_MODULE
298 },
299 .show = &w1_master_attribute_show_name,
300};
301
302static struct bin_attribute w1_slave_bin_attribute = {
303 .attr = {
304 .name = "w1_slave",
305 .mode = S_IRUGO,
306 .owner = THIS_MODULE,
307 },
308 .size = W1_SLAVE_DATA_SIZE,
309 .read = &w1_default_read_bin,
310};
311
312static int __w1_attach_slave_device(struct w1_slave *sl)
313{
314 int err;
315
316 sl->dev.parent = &sl->master->dev;
317 sl->dev.driver = sl->master->driver;
318 sl->dev.bus = &w1_bus_type;
319 sl->dev.release = &w1_slave_release;
320
321 snprintf(&sl->dev.bus_id[0], sizeof(sl->dev.bus_id),
322 "%02x-%012llx",
323 (unsigned int) sl->reg_num.family,
324 (unsigned long long) sl->reg_num.id);
325 snprintf (&sl->name[0], sizeof(sl->name),
326 "%02x-%012llx",
327 (unsigned int) sl->reg_num.family,
328 (unsigned long long) sl->reg_num.id);
329
330 dev_dbg(&sl->dev, "%s: registering %s.\n", __func__,
331 &sl->dev.bus_id[0]);
332
333 err = device_register(&sl->dev);
334 if (err < 0) {
335 dev_err(&sl->dev,
336 "Device registration [%s] failed. err=%d\n",
337 sl->dev.bus_id, err);
338 return err;
339 }
340
341 memcpy(&sl->attr_bin, &w1_slave_bin_attribute, sizeof(sl->attr_bin));
342 memcpy(&sl->attr_name, &w1_slave_attribute, sizeof(sl->attr_name));
343 memcpy(&sl->attr_val, &w1_slave_attribute_val, sizeof(sl->attr_val));
344
345 sl->attr_bin.read = sl->family->fops->rbin;
346 sl->attr_name.show = sl->family->fops->rname;
347 sl->attr_val.show = sl->family->fops->rval;
348 sl->attr_val.attr.name = sl->family->fops->rvalname;
349
350 err = device_create_file(&sl->dev, &sl->attr_name);
351 if (err < 0) {
352 dev_err(&sl->dev,
353 "sysfs file creation for [%s] failed. err=%d\n",
354 sl->dev.bus_id, err);
355 device_unregister(&sl->dev);
356 return err;
357 }
358
359 err = device_create_file(&sl->dev, &sl->attr_val);
360 if (err < 0) {
361 dev_err(&sl->dev,
362 "sysfs file creation for [%s] failed. err=%d\n",
363 sl->dev.bus_id, err);
364 device_remove_file(&sl->dev, &sl->attr_name);
365 device_unregister(&sl->dev);
366 return err;
367 }
368
369 err = sysfs_create_bin_file(&sl->dev.kobj, &sl->attr_bin);
370 if (err < 0) {
371 dev_err(&sl->dev,
372 "sysfs file creation for [%s] failed. err=%d\n",
373 sl->dev.bus_id, err);
374 device_remove_file(&sl->dev, &sl->attr_name);
375 device_remove_file(&sl->dev, &sl->attr_val);
376 device_unregister(&sl->dev);
377 return err;
378 }
379
380 list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
381
382 return 0;
383}
384
385static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
386{
387 struct w1_slave *sl;
388 struct w1_family *f;
389 int err;
390 struct w1_netlink_msg msg;
391
392 sl = kmalloc(sizeof(struct w1_slave), GFP_KERNEL);
393 if (!sl) {
394 dev_err(&dev->dev,
395 "%s: failed to allocate new slave device.\n",
396 __func__);
397 return -ENOMEM;
398 }
399
400 memset(sl, 0, sizeof(*sl));
401
402 sl->owner = THIS_MODULE;
403 sl->master = dev;
404 set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
405
406 memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
407 atomic_set(&sl->refcnt, 0);
408 init_completion(&sl->dev_released);
409
410 spin_lock(&w1_flock);
411 f = w1_family_registered(rn->family);
412 if (!f) {
413 spin_unlock(&w1_flock);
414 dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n",
415 rn->family, rn->family,
416 (unsigned long long)rn->id, rn->crc);
417 kfree(sl);
418 return -ENODEV;
419 }
420 __w1_family_get(f);
421 spin_unlock(&w1_flock);
422
423 sl->family = f;
424
425
426 err = __w1_attach_slave_device(sl);
427 if (err < 0) {
428 dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__,
429 sl->name);
430 w1_family_put(sl->family);
431 kfree(sl);
432 return err;
433 }
434
435 sl->ttl = dev->slave_ttl;
436 dev->slave_count++;
437
438 memcpy(&msg.id.id, rn, sizeof(msg.id.id));
439 msg.type = W1_SLAVE_ADD;
440 w1_netlink_send(dev, &msg);
441
442 return 0;
443}
444
445static void w1_slave_detach(struct w1_slave *sl)
446{
447 struct w1_netlink_msg msg;
448
449 dev_info(&sl->dev, "%s: detaching %s.\n", __func__, sl->name);
450
451 while (atomic_read(&sl->refcnt)) {
452 printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
453 sl->name, atomic_read(&sl->refcnt));
454
455 if (msleep_interruptible(1000))
456 flush_signals(current);
457 }
458
459 sysfs_remove_bin_file (&sl->dev.kobj, &sl->attr_bin);
460 device_remove_file(&sl->dev, &sl->attr_name);
461 device_remove_file(&sl->dev, &sl->attr_val);
462 device_unregister(&sl->dev);
463 w1_family_put(sl->family);
464
465 memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id));
466 msg.type = W1_SLAVE_REMOVE;
467 w1_netlink_send(sl->master, &msg);
468}
469
470static struct w1_master *w1_search_master(unsigned long data)
471{
472 struct w1_master *dev;
473 int found = 0;
474
475 spin_lock_irq(&w1_mlock);
476 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
477 if (dev->bus_master->data == data) {
478 found = 1;
479 atomic_inc(&dev->refcnt);
480 break;
481 }
482 }
483 spin_unlock_irq(&w1_mlock);
484
485 return (found)?dev:NULL;
486}
487
488void w1_slave_found(unsigned long data, u64 rn)
489{
490 int slave_count;
491 struct w1_slave *sl;
492 struct list_head *ent;
493 struct w1_reg_num *tmp;
494 int family_found = 0;
495 struct w1_master *dev;
496
497 dev = w1_search_master(data);
498 if (!dev) {
499 printk(KERN_ERR "Failed to find w1 master device for data %08lx, it is impossible.\n",
500 data);
501 return;
502 }
503
504 tmp = (struct w1_reg_num *) &rn;
505
506 slave_count = 0;
507 list_for_each(ent, &dev->slist) {
508
509 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
510
511 if (sl->reg_num.family == tmp->family &&
512 sl->reg_num.id == tmp->id &&
513 sl->reg_num.crc == tmp->crc) {
514 set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
515 break;
516 }
517 else if (sl->reg_num.family == tmp->family) {
518 family_found = 1;
519 break;
520 }
521
522 slave_count++;
523 }
524
johnpol@2ka.mipt.ru8523ff42005-04-18 21:16:57 -0700525 rn = cpu_to_le64(rn);
526
527 if (slave_count == dev->slave_count &&
528 rn && ((le64_to_cpu(rn) >> 56) & 0xff) == w1_calc_crc8((u8 *)&rn, 7)) {
529 w1_attach_slave_device(dev, tmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 }
531
532 atomic_dec(&dev->refcnt);
533}
534
535void w1_search(struct w1_master *dev)
536{
537 u64 last, rn, tmp;
538 int i, count = 0;
539 int last_family_desc, last_zero, last_device;
540 int search_bit, id_bit, comp_bit, desc_bit;
541
542 search_bit = id_bit = comp_bit = 0;
543 rn = tmp = last = 0;
544 last_device = last_zero = last_family_desc = 0;
545
546 desc_bit = 64;
547
548 while (!(id_bit && comp_bit) && !last_device
549 && count++ < dev->max_slave_count) {
550 last = rn;
551 rn = 0;
552
553 last_family_desc = 0;
554
555 /*
556 * Reset bus and all 1-wire device state machines
557 * so they can respond to our requests.
558 *
559 * Return 0 - device(s) present, 1 - no devices present.
560 */
561 if (w1_reset_bus(dev)) {
562 dev_info(&dev->dev, "No devices present on the wire.\n");
563 break;
564 }
565
566#if 1
567 w1_write_8(dev, W1_SEARCH);
568 for (i = 0; i < 64; ++i) {
569 /*
570 * Read 2 bits from bus.
571 * All who don't sleep must send ID bit and COMPLEMENT ID bit.
572 * They actually are ANDed between all senders.
573 */
574 id_bit = w1_touch_bit(dev, 1);
575 comp_bit = w1_touch_bit(dev, 1);
576
577 if (id_bit && comp_bit)
578 break;
579
580 if (id_bit == 0 && comp_bit == 0) {
581 if (i == desc_bit)
582 search_bit = 1;
583 else if (i > desc_bit)
584 search_bit = 0;
585 else
586 search_bit = ((last >> i) & 0x1);
587
588 if (search_bit == 0) {
589 last_zero = i;
590 if (last_zero < 9)
591 last_family_desc = last_zero;
592 }
593
594 }
595 else
596 search_bit = id_bit;
597
598 tmp = search_bit;
599 rn |= (tmp << i);
600
601 /*
602 * Write 1 bit to bus
603 * and make all who don't have "search_bit" in "i"'th position
604 * in it's registration number sleep.
605 */
606 if (dev->bus_master->touch_bit)
607 w1_touch_bit(dev, search_bit);
608 else
609 w1_write_bit(dev, search_bit);
610
611 }
612#endif
613
614 if (desc_bit == last_zero)
615 last_device = 1;
616
617 desc_bit = last_zero;
618
619 w1_slave_found(dev->bus_master->data, rn);
620 }
621}
622
623int w1_create_master_attributes(struct w1_master *dev)
624{
625 if ( device_create_file(&dev->dev, &w1_master_attribute_slaves) < 0 ||
626 device_create_file(&dev->dev, &w1_master_attribute_slave_count) < 0 ||
627 device_create_file(&dev->dev, &w1_master_attribute_attempts) < 0 ||
628 device_create_file(&dev->dev, &w1_master_attribute_max_slave_count) < 0 ||
629 device_create_file(&dev->dev, &w1_master_attribute_timeout) < 0||
630 device_create_file(&dev->dev, &w1_master_attribute_pointer) < 0||
631 device_create_file(&dev->dev, &w1_master_attribute_name) < 0)
632 return -EINVAL;
633
634 return 0;
635}
636
637void w1_destroy_master_attributes(struct w1_master *dev)
638{
639 device_remove_file(&dev->dev, &w1_master_attribute_slaves);
640 device_remove_file(&dev->dev, &w1_master_attribute_slave_count);
641 device_remove_file(&dev->dev, &w1_master_attribute_attempts);
642 device_remove_file(&dev->dev, &w1_master_attribute_max_slave_count);
643 device_remove_file(&dev->dev, &w1_master_attribute_timeout);
644 device_remove_file(&dev->dev, &w1_master_attribute_pointer);
645 device_remove_file(&dev->dev, &w1_master_attribute_name);
646}
647
648
649int w1_control(void *data)
650{
651 struct w1_slave *sl;
652 struct w1_master *dev;
653 struct list_head *ent, *ment, *n, *mn;
654 int err, have_to_wait = 0;
655
656 daemonize("w1_control");
657 allow_signal(SIGTERM);
658
659 while (!control_needs_exit || have_to_wait) {
660 have_to_wait = 0;
661
662 try_to_freeze(PF_FREEZE);
663 msleep_interruptible(w1_timeout * 1000);
664
665 if (signal_pending(current))
666 flush_signals(current);
667
668 list_for_each_safe(ment, mn, &w1_masters) {
669 dev = list_entry(ment, struct w1_master, w1_master_entry);
670
671 if (!control_needs_exit && !dev->need_exit)
672 continue;
673 /*
674 * Little race: we can create thread but not set the flag.
675 * Get a chance for external process to set flag up.
676 */
677 if (!dev->initialized) {
678 have_to_wait = 1;
679 continue;
680 }
681
682 spin_lock(&w1_mlock);
683 list_del(&dev->w1_master_entry);
684 spin_unlock(&w1_mlock);
685
686 if (control_needs_exit) {
687 dev->need_exit = 1;
688
689 err = kill_proc(dev->kpid, SIGTERM, 1);
690 if (err)
691 dev_err(&dev->dev,
692 "Failed to send signal to w1 kernel thread %d.\n",
693 dev->kpid);
694 }
695
696 wait_for_completion(&dev->dev_exited);
697
698 list_for_each_safe(ent, n, &dev->slist) {
699 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
700
701 if (!sl)
702 dev_warn(&dev->dev,
703 "%s: slave entry is NULL.\n",
704 __func__);
705 else {
706 list_del(&sl->w1_slave_entry);
707
708 w1_slave_detach(sl);
709 kfree(sl);
710 }
711 }
712 w1_destroy_master_attributes(dev);
713 atomic_dec(&dev->refcnt);
714 }
715 }
716
717 complete_and_exit(&w1_control_complete, 0);
718}
719
720int w1_process(void *data)
721{
722 struct w1_master *dev = (struct w1_master *) data;
723 struct list_head *ent, *n;
724 struct w1_slave *sl;
725
726 daemonize("%s", dev->name);
727 allow_signal(SIGTERM);
728
729 while (!dev->need_exit) {
730 try_to_freeze(PF_FREEZE);
731 msleep_interruptible(w1_timeout * 1000);
732
733 if (signal_pending(current))
734 flush_signals(current);
735
736 if (dev->need_exit)
737 break;
738
739 if (!dev->initialized)
740 continue;
741
742 if (down_interruptible(&dev->mutex))
743 continue;
744
745 list_for_each_safe(ent, n, &dev->slist) {
746 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
747
748 if (sl)
749 clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
750 }
751
752 w1_search_devices(dev, w1_slave_found);
753
754 list_for_each_safe(ent, n, &dev->slist) {
755 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
756
757 if (sl && !test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl) {
758 list_del (&sl->w1_slave_entry);
759
760 w1_slave_detach (sl);
761 kfree (sl);
762
763 dev->slave_count--;
764 }
765 else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags))
766 sl->ttl = dev->slave_ttl;
767 }
768 up(&dev->mutex);
769 }
770
771 atomic_dec(&dev->refcnt);
772 complete_and_exit(&dev->dev_exited, 0);
773
774 return 0;
775}
776
777int w1_init(void)
778{
779 int retval;
780
781 printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n");
782
783 retval = bus_register(&w1_bus_type);
784 if (retval) {
785 printk(KERN_ERR "Failed to register bus. err=%d.\n", retval);
786 goto err_out_exit_init;
787 }
788
789 retval = driver_register(&w1_driver);
790 if (retval) {
791 printk(KERN_ERR
792 "Failed to register master driver. err=%d.\n",
793 retval);
794 goto err_out_bus_unregister;
795 }
796
797 control_thread = kernel_thread(&w1_control, NULL, 0);
798 if (control_thread < 0) {
799 printk(KERN_ERR "Failed to create control thread. err=%d\n",
800 control_thread);
801 retval = control_thread;
802 goto err_out_driver_unregister;
803 }
804
805 return 0;
806
807err_out_driver_unregister:
808 driver_unregister(&w1_driver);
809
810err_out_bus_unregister:
811 bus_unregister(&w1_bus_type);
812
813err_out_exit_init:
814 return retval;
815}
816
817void w1_fini(void)
818{
819 struct w1_master *dev;
820 struct list_head *ent, *n;
821
822 list_for_each_safe(ent, n, &w1_masters) {
823 dev = list_entry(ent, struct w1_master, w1_master_entry);
824 __w1_remove_master_device(dev);
825 }
826
827 control_needs_exit = 1;
828
829 wait_for_completion(&w1_control_complete);
830
831 driver_unregister(&w1_driver);
832 bus_unregister(&w1_bus_type);
833}
834
835module_init(w1_init);
836module_exit(w1_fini);