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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Evgeniy Polyakov77859252005-05-20 22:33:25 +04002 * w1.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Evgeniy Polyakov77859252005-05-20 22:33:25 +04005 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
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>
Evgeniy Polyakov674a396c2006-02-20 11:15:37 +030033#include <linux/kthread.h>
Nigel Cunningham7dfb7102006-12-06 20:34:23 -080034#include <linux/freezer.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36#include <asm/atomic.h>
37
38#include "w1.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include "w1_log.h"
40#include "w1_int.h"
41#include "w1_family.h"
42#include "w1_netlink.h"
43
44MODULE_LICENSE("GPL");
45MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
46MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");
47
48static int w1_timeout = 10;
49int w1_max_slave_count = 10;
50int w1_max_slave_ttl = 10;
51
52module_param_named(timeout, w1_timeout, int, 0);
53module_param_named(max_slave_count, w1_max_slave_count, int, 0);
54module_param_named(slave_ttl, w1_max_slave_ttl, int, 0);
55
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +040056DEFINE_MUTEX(w1_mlock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057LIST_HEAD(w1_masters);
58
David Fries9b467412008-10-15 22:04:43 -070059static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn);
60
Linus Torvalds1da177e2005-04-16 15:20:36 -070061static int w1_master_match(struct device *dev, struct device_driver *drv)
62{
63 return 1;
64}
65
66static int w1_master_probe(struct device *dev)
67{
68 return -ENODEV;
69}
70
Linus Torvalds1da177e2005-04-16 15:20:36 -070071static void w1_master_release(struct device *dev)
72{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +040073 struct w1_master *md = dev_to_w1_master(dev);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +040074
75 dev_dbg(dev, "%s: Releasing %s.\n", __func__, md->name);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +040076 memset(md, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master));
77 kfree(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078}
79
80static void w1_slave_release(struct device *dev)
81{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +040082 struct w1_slave *sl = dev_to_w1_slave(dev);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +040083
David Fries7dc8f522008-10-15 22:04:58 -070084 dev_dbg(dev, "%s: Releasing %s.\n", __func__, sl->name);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +040085
86 while (atomic_read(&sl->refcnt)) {
David Fries7dc8f522008-10-15 22:04:58 -070087 dev_dbg(dev, "Waiting for %s to become free: refcnt=%d.\n",
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +040088 sl->name, atomic_read(&sl->refcnt));
89 if (msleep_interruptible(1000))
90 flush_signals(current);
91 }
92
93 w1_family_put(sl->family);
94 sl->master->slave_count--;
95
96 complete(&sl->released);
Linus Torvalds1da177e2005-04-16 15:20:36 -070097}
98
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +040099static ssize_t w1_slave_read_name(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100{
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400101 struct w1_slave *sl = dev_to_w1_slave(dev);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400102
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400103 return sprintf(buf, "%s\n", sl->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104}
105
David Fries07e00342008-10-15 22:04:50 -0700106static ssize_t w1_slave_read_id(struct device *dev,
107 struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108{
David Fries07e00342008-10-15 22:04:50 -0700109 struct w1_slave *sl = dev_to_w1_slave(dev);
110 ssize_t count = sizeof(sl->reg_num);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
David Fries07e00342008-10-15 22:04:50 -0700112 memcpy(buf, (u8 *)&sl->reg_num, count);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400113 return count;
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400114}
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400115
116static struct device_attribute w1_slave_attr_name =
117 __ATTR(name, S_IRUGO, w1_slave_read_name, NULL);
David Fries07e00342008-10-15 22:04:50 -0700118static struct device_attribute w1_slave_attr_id =
119 __ATTR(id, S_IRUGO, w1_slave_read_id, NULL);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400120
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400121/* Default family */
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300122
Zhang Rui91a69022007-06-09 13:57:22 +0800123static ssize_t w1_default_write(struct kobject *kobj,
124 struct bin_attribute *bin_attr,
125 char *buf, loff_t off, size_t count)
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300126{
127 struct w1_slave *sl = kobj_to_w1_slave(kobj);
128
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400129 mutex_lock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300130 if (w1_reset_select_slave(sl)) {
131 count = 0;
132 goto out_up;
133 }
134
135 w1_write_block(sl->master, buf, count);
136
137out_up:
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400138 mutex_unlock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300139 return count;
140}
141
Zhang Rui91a69022007-06-09 13:57:22 +0800142static ssize_t w1_default_read(struct kobject *kobj,
143 struct bin_attribute *bin_attr,
144 char *buf, loff_t off, size_t count)
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300145{
146 struct w1_slave *sl = kobj_to_w1_slave(kobj);
147
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400148 mutex_lock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300149 w1_read_block(sl->master, buf, count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400150 mutex_unlock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300151 return count;
152}
153
154static struct bin_attribute w1_default_attr = {
155 .attr = {
156 .name = "rw",
157 .mode = S_IRUGO | S_IWUSR,
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300158 },
159 .size = PAGE_SIZE,
160 .read = w1_default_read,
161 .write = w1_default_write,
162};
163
164static int w1_default_add_slave(struct w1_slave *sl)
165{
166 return sysfs_create_bin_file(&sl->dev.kobj, &w1_default_attr);
167}
168
169static void w1_default_remove_slave(struct w1_slave *sl)
170{
171 sysfs_remove_bin_file(&sl->dev.kobj, &w1_default_attr);
172}
173
174static struct w1_family_ops w1_default_fops = {
175 .add_slave = w1_default_add_slave,
176 .remove_slave = w1_default_remove_slave,
177};
178
179static struct w1_family w1_default_family = {
180 .fops = &w1_default_fops,
181};
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400182
Kay Sievers7eff2e72007-08-14 15:15:12 +0200183static int w1_uevent(struct device *dev, struct kobj_uevent_env *env);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185static struct bus_type w1_bus_type = {
186 .name = "w1",
187 .match = w1_master_match,
Kay Sievers312c0042005-11-16 09:00:00 +0100188 .uevent = w1_uevent,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189};
190
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400191struct device_driver w1_master_driver = {
192 .name = "w1_master_driver",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 .bus = &w1_bus_type,
194 .probe = w1_master_probe,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195};
196
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400197struct device w1_master_device = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 .parent = NULL,
199 .bus = &w1_bus_type,
Kay Sievers40f91de2009-01-06 10:44:34 -0800200 .init_name = "w1 bus master",
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400201 .driver = &w1_master_driver,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 .release = &w1_master_release
203};
204
Evgeniy Polyakov2c5bfda2006-04-04 20:35:22 +0400205static struct device_driver w1_slave_driver = {
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400206 .name = "w1_slave_driver",
207 .bus = &w1_bus_type,
208};
209
Evgeniy Polyakov2c5bfda2006-04-04 20:35:22 +0400210#if 0
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400211struct device w1_slave_device = {
212 .parent = NULL,
213 .bus = &w1_bus_type,
Kay Sievers40f91de2009-01-06 10:44:34 -0800214 .init_name = "w1 bus slave",
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400215 .driver = &w1_slave_driver,
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400216 .release = &w1_slave_release
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400217};
Evgeniy Polyakov2c5bfda2006-04-04 20:35:22 +0400218#endif /* 0 */
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400219
Yani Ioannou060b8842005-05-17 06:44:04 -0400220static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400222 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400224
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400225 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 count = sprintf(buf, "%s\n", md->name);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400227 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228
229 return count;
230}
231
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400232static ssize_t w1_master_attribute_store_search(struct device * dev,
233 struct device_attribute *attr,
234 const char * buf, size_t count)
235{
David Fries6a158c02008-10-15 22:04:42 -0700236 long tmp;
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400237 struct w1_master *md = dev_to_w1_master(dev);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400238
David Fries6a158c02008-10-15 22:04:42 -0700239 if (strict_strtol(buf, 0, &tmp) == -EINVAL)
240 return -EINVAL;
241
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400242 mutex_lock(&md->mutex);
David Fries6a158c02008-10-15 22:04:42 -0700243 md->search_count = tmp;
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400244 mutex_unlock(&md->mutex);
David Fries3c52e4e2008-10-15 22:04:41 -0700245 wake_up_process(md->thread);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400246
247 return count;
248}
249
250static ssize_t w1_master_attribute_show_search(struct device *dev,
251 struct device_attribute *attr,
252 char *buf)
253{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400254 struct w1_master *md = dev_to_w1_master(dev);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400255 ssize_t count;
256
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400257 mutex_lock(&md->mutex);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400258 count = sprintf(buf, "%d\n", md->search_count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400259 mutex_unlock(&md->mutex);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400260
261 return count;
262}
263
David Fries6a158c02008-10-15 22:04:42 -0700264static ssize_t w1_master_attribute_store_pullup(struct device *dev,
265 struct device_attribute *attr,
266 const char *buf, size_t count)
267{
268 long tmp;
269 struct w1_master *md = dev_to_w1_master(dev);
270
271 if (strict_strtol(buf, 0, &tmp) == -EINVAL)
272 return -EINVAL;
273
274 mutex_lock(&md->mutex);
275 md->enable_pullup = tmp;
276 mutex_unlock(&md->mutex);
277 wake_up_process(md->thread);
278
279 return count;
280}
281
282static ssize_t w1_master_attribute_show_pullup(struct device *dev,
283 struct device_attribute *attr,
284 char *buf)
285{
286 struct w1_master *md = dev_to_w1_master(dev);
287 ssize_t count;
288
289 mutex_lock(&md->mutex);
290 count = sprintf(buf, "%d\n", md->enable_pullup);
291 mutex_unlock(&md->mutex);
292
293 return count;
294}
295
Yani Ioannou060b8842005-05-17 06:44:04 -0400296static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400298 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400300
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400301 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 count = sprintf(buf, "0x%p\n", md->bus_master);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400303 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 return count;
305}
306
Yani Ioannou060b8842005-05-17 06:44:04 -0400307static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308{
309 ssize_t count;
310 count = sprintf(buf, "%d\n", w1_timeout);
311 return count;
312}
313
Yani Ioannou060b8842005-05-17 06:44:04 -0400314static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400316 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400318
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400319 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 count = sprintf(buf, "%d\n", md->max_slave_count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400321 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 return count;
323}
324
Yani Ioannou060b8842005-05-17 06:44:04 -0400325static ssize_t w1_master_attribute_show_attempts(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400327 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400329
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400330 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 count = sprintf(buf, "%lu\n", md->attempts);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400332 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333 return count;
334}
335
Yani Ioannou060b8842005-05-17 06:44:04 -0400336static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400338 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400340
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400341 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 count = sprintf(buf, "%d\n", md->slave_count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400343 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 return count;
345}
346
David Fries9b467412008-10-15 22:04:43 -0700347static ssize_t w1_master_attribute_show_slaves(struct device *dev,
348 struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400350 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 int c = PAGE_SIZE;
352
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400353 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
355 if (md->slave_count == 0)
356 c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
357 else {
358 struct list_head *ent, *n;
359 struct w1_slave *sl;
360
361 list_for_each_safe(ent, n, &md->slist) {
362 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
363
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400364 c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 }
366 }
367
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400368 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
370 return PAGE_SIZE - c;
371}
372
David Fries9b467412008-10-15 22:04:43 -0700373static ssize_t w1_master_attribute_show_add(struct device *dev,
374 struct device_attribute *attr, char *buf)
375{
376 int c = PAGE_SIZE;
377 c -= snprintf(buf+PAGE_SIZE - c, c,
378 "write device id xx-xxxxxxxxxxxx to add slave\n");
379 return PAGE_SIZE - c;
380}
381
382static int w1_atoreg_num(struct device *dev, const char *buf, size_t count,
383 struct w1_reg_num *rn)
384{
385 unsigned int family;
386 unsigned long long id;
387 int i;
388 u64 rn64_le;
389
390 /* The CRC value isn't read from the user because the sysfs directory
391 * doesn't include it and most messages from the bus search don't
392 * print it either. It would be unreasonable for the user to then
393 * provide it.
394 */
395 const char *error_msg = "bad slave string format, expecting "
396 "ff-dddddddddddd\n";
397
398 if (buf[2] != '-') {
399 dev_err(dev, "%s", error_msg);
400 return -EINVAL;
401 }
402 i = sscanf(buf, "%02x-%012llx", &family, &id);
403 if (i != 2) {
404 dev_err(dev, "%s", error_msg);
405 return -EINVAL;
406 }
407 rn->family = family;
408 rn->id = id;
409
410 rn64_le = cpu_to_le64(*(u64 *)rn);
411 rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7);
412
413#if 0
414 dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n",
415 rn->family, (unsigned long long)rn->id, rn->crc);
416#endif
417
418 return 0;
419}
420
421/* Searches the slaves in the w1_master and returns a pointer or NULL.
422 * Note: must hold the mutex
423 */
424static struct w1_slave *w1_slave_search_device(struct w1_master *dev,
425 struct w1_reg_num *rn)
426{
427 struct w1_slave *sl;
428 list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
429 if (sl->reg_num.family == rn->family &&
430 sl->reg_num.id == rn->id &&
431 sl->reg_num.crc == rn->crc) {
432 return sl;
433 }
434 }
435 return NULL;
436}
437
438static ssize_t w1_master_attribute_store_add(struct device *dev,
439 struct device_attribute *attr,
440 const char *buf, size_t count)
441{
442 struct w1_master *md = dev_to_w1_master(dev);
443 struct w1_reg_num rn;
444 struct w1_slave *sl;
445 ssize_t result = count;
446
447 if (w1_atoreg_num(dev, buf, count, &rn))
448 return -EINVAL;
449
450 mutex_lock(&md->mutex);
451 sl = w1_slave_search_device(md, &rn);
452 /* It would be nice to do a targeted search one the one-wire bus
453 * for the new device to see if it is out there or not. But the
454 * current search doesn't support that.
455 */
456 if (sl) {
457 dev_info(dev, "Device %s already exists\n", sl->name);
458 result = -EINVAL;
459 } else {
460 w1_attach_slave_device(md, &rn);
461 }
462 mutex_unlock(&md->mutex);
463
464 return result;
465}
466
467static ssize_t w1_master_attribute_show_remove(struct device *dev,
468 struct device_attribute *attr, char *buf)
469{
470 int c = PAGE_SIZE;
471 c -= snprintf(buf+PAGE_SIZE - c, c,
472 "write device id xx-xxxxxxxxxxxx to remove slave\n");
473 return PAGE_SIZE - c;
474}
475
476static ssize_t w1_master_attribute_store_remove(struct device *dev,
477 struct device_attribute *attr,
478 const char *buf, size_t count)
479{
480 struct w1_master *md = dev_to_w1_master(dev);
481 struct w1_reg_num rn;
482 struct w1_slave *sl;
483 ssize_t result = count;
484
485 if (w1_atoreg_num(dev, buf, count, &rn))
486 return -EINVAL;
487
488 mutex_lock(&md->mutex);
489 sl = w1_slave_search_device(md, &rn);
490 if (sl) {
491 w1_slave_detach(sl);
492 } else {
493 dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family,
494 (unsigned long long)rn.id);
495 result = -EINVAL;
496 }
497 mutex_unlock(&md->mutex);
498
499 return result;
500}
501
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400502#define W1_MASTER_ATTR_RO(_name, _mode) \
503 struct device_attribute w1_master_attribute_##_name = \
504 __ATTR(w1_master_##_name, _mode, \
505 w1_master_attribute_show_##_name, NULL)
506
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400507#define W1_MASTER_ATTR_RW(_name, _mode) \
508 struct device_attribute w1_master_attribute_##_name = \
509 __ATTR(w1_master_##_name, _mode, \
510 w1_master_attribute_show_##_name, \
511 w1_master_attribute_store_##_name)
512
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400513static W1_MASTER_ATTR_RO(name, S_IRUGO);
514static W1_MASTER_ATTR_RO(slaves, S_IRUGO);
515static W1_MASTER_ATTR_RO(slave_count, S_IRUGO);
516static W1_MASTER_ATTR_RO(max_slave_count, S_IRUGO);
517static W1_MASTER_ATTR_RO(attempts, S_IRUGO);
518static W1_MASTER_ATTR_RO(timeout, S_IRUGO);
519static W1_MASTER_ATTR_RO(pointer, S_IRUGO);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400520static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUGO);
David Fries6a158c02008-10-15 22:04:42 -0700521static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUGO);
David Fries9b467412008-10-15 22:04:43 -0700522static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUGO);
523static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUGO);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400524
525static struct attribute *w1_master_default_attrs[] = {
526 &w1_master_attribute_name.attr,
527 &w1_master_attribute_slaves.attr,
528 &w1_master_attribute_slave_count.attr,
529 &w1_master_attribute_max_slave_count.attr,
530 &w1_master_attribute_attempts.attr,
531 &w1_master_attribute_timeout.attr,
532 &w1_master_attribute_pointer.attr,
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400533 &w1_master_attribute_search.attr,
David Fries6a158c02008-10-15 22:04:42 -0700534 &w1_master_attribute_pullup.attr,
David Fries9b467412008-10-15 22:04:43 -0700535 &w1_master_attribute_add.attr,
536 &w1_master_attribute_remove.attr,
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400537 NULL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538};
539
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400540static struct attribute_group w1_master_defattr_group = {
541 .attrs = w1_master_default_attrs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542};
543
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400544int w1_create_master_attributes(struct w1_master *master)
545{
546 return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group);
547}
548
David Friesc30c9b12008-10-15 22:04:38 -0700549void w1_destroy_master_attributes(struct w1_master *master)
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400550{
551 sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group);
552}
553
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400554#ifdef CONFIG_HOTPLUG
Kay Sievers7eff2e72007-08-14 15:15:12 +0200555static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400556{
557 struct w1_master *md = NULL;
558 struct w1_slave *sl = NULL;
559 char *event_owner, *name;
Kay Sievers7eff2e72007-08-14 15:15:12 +0200560 int err;
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400561
562 if (dev->driver == &w1_master_driver) {
563 md = container_of(dev, struct w1_master, dev);
564 event_owner = "master";
565 name = md->name;
566 } else if (dev->driver == &w1_slave_driver) {
567 sl = container_of(dev, struct w1_slave, dev);
568 event_owner = "slave";
569 name = sl->name;
570 } else {
Kay Sievers312c0042005-11-16 09:00:00 +0100571 dev_dbg(dev, "Unknown event.\n");
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400572 return -EINVAL;
573 }
574
Andrew Mortonc6976a42006-05-14 21:43:50 -0700575 dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800576 event_owner, name, dev_name(dev));
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400577
578 if (dev->driver != &w1_slave_driver || !sl)
579 return 0;
580
Kay Sievers7eff2e72007-08-14 15:15:12 +0200581 err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family);
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400582 if (err)
583 return err;
584
Kay Sievers7eff2e72007-08-14 15:15:12 +0200585 err = add_uevent_var(env, "W1_SLAVE_ID=%024LX",
586 (unsigned long long)sl->reg_num.id);
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400587 if (err)
588 return err;
589
590 return 0;
591};
592#else
Kay Sievers7eff2e72007-08-14 15:15:12 +0200593static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400594{
595 return 0;
596}
597#endif
598
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599static int __w1_attach_slave_device(struct w1_slave *sl)
600{
601 int err;
602
603 sl->dev.parent = &sl->master->dev;
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400604 sl->dev.driver = &w1_slave_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 sl->dev.bus = &w1_bus_type;
606 sl->dev.release = &w1_slave_release;
607
Kay Sievers40f91de2009-01-06 10:44:34 -0800608 dev_set_name(&sl->dev, "%02x-%012llx",
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400609 (unsigned int) sl->reg_num.family,
610 (unsigned long long) sl->reg_num.id);
611 snprintf(&sl->name[0], sizeof(sl->name),
612 "%02x-%012llx",
613 (unsigned int) sl->reg_num.family,
614 (unsigned long long) sl->reg_num.id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
Andrew Mortonc6976a42006-05-14 21:43:50 -0700616 dev_dbg(&sl->dev, "%s: registering %s as %p.\n", __func__,
Kay Sievers40f91de2009-01-06 10:44:34 -0800617 dev_name(&sl->dev), sl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618
619 err = device_register(&sl->dev);
620 if (err < 0) {
621 dev_err(&sl->dev,
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400622 "Device registration [%s] failed. err=%d\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800623 dev_name(&sl->dev), err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 return err;
625 }
626
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400627 /* Create "name" entry */
628 err = device_create_file(&sl->dev, &w1_slave_attr_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 if (err < 0) {
630 dev_err(&sl->dev,
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400631 "sysfs file creation for [%s] failed. err=%d\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800632 dev_name(&sl->dev), err);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400633 goto out_unreg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 }
635
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400636 /* Create "id" entry */
David Fries07e00342008-10-15 22:04:50 -0700637 err = device_create_file(&sl->dev, &w1_slave_attr_id);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400638 if (err < 0) {
639 dev_err(&sl->dev,
640 "sysfs file creation for [%s] failed. err=%d\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800641 dev_name(&sl->dev), err);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400642 goto out_rem1;
643 }
644
645 /* if the family driver needs to initialize something... */
646 if (sl->family->fops && sl->family->fops->add_slave &&
647 ((err = sl->family->fops->add_slave(sl)) < 0)) {
648 dev_err(&sl->dev,
649 "sysfs file creation for [%s] failed. err=%d\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800650 dev_name(&sl->dev), err);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400651 goto out_rem2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 }
653
654 list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
655
656 return 0;
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400657
658out_rem2:
David Fries07e00342008-10-15 22:04:50 -0700659 device_remove_file(&sl->dev, &w1_slave_attr_id);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400660out_rem1:
661 device_remove_file(&sl->dev, &w1_slave_attr_name);
662out_unreg:
663 device_unregister(&sl->dev);
664 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665}
666
667static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
668{
669 struct w1_slave *sl;
670 struct w1_family *f;
671 int err;
672 struct w1_netlink_msg msg;
673
Yoann Padioleaudd00cc42007-07-19 01:49:03 -0700674 sl = kzalloc(sizeof(struct w1_slave), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675 if (!sl) {
676 dev_err(&dev->dev,
677 "%s: failed to allocate new slave device.\n",
678 __func__);
679 return -ENOMEM;
680 }
681
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682
683 sl->owner = THIS_MODULE;
684 sl->master = dev;
685 set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
686
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300687 memset(&msg, 0, sizeof(msg));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
689 atomic_set(&sl->refcnt, 0);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400690 init_completion(&sl->released);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691
692 spin_lock(&w1_flock);
693 f = w1_family_registered(rn->family);
694 if (!f) {
Evgeniy Polyakov99c5bfe2005-06-04 01:31:26 +0400695 f= &w1_default_family;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n",
697 rn->family, rn->family,
698 (unsigned long long)rn->id, rn->crc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 }
700 __w1_family_get(f);
701 spin_unlock(&w1_flock);
702
703 sl->family = f;
704
705
706 err = __w1_attach_slave_device(sl);
707 if (err < 0) {
708 dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__,
709 sl->name);
710 w1_family_put(sl->family);
711 kfree(sl);
712 return err;
713 }
714
715 sl->ttl = dev->slave_ttl;
716 dev->slave_count++;
717
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300718 memcpy(msg.id.id, rn, sizeof(msg.id));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719 msg.type = W1_SLAVE_ADD;
720 w1_netlink_send(dev, &msg);
721
722 return 0;
723}
724
David Friesc30c9b12008-10-15 22:04:38 -0700725void w1_slave_detach(struct w1_slave *sl)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726{
727 struct w1_netlink_msg msg;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400728
Evgeniy Polyakov7c8f5702005-08-11 17:27:50 +0400729 dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__, sl->name, sl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400731 list_del(&sl->w1_slave_entry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400733 if (sl->family->fops && sl->family->fops->remove_slave)
734 sl->family->fops->remove_slave(sl);
735
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300736 memset(&msg, 0, sizeof(msg));
737 memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 msg.type = W1_SLAVE_REMOVE;
739 w1_netlink_send(sl->master, &msg);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400740
David Fries07e00342008-10-15 22:04:50 -0700741 device_remove_file(&sl->dev, &w1_slave_attr_id);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400742 device_remove_file(&sl->dev, &w1_slave_attr_name);
743 device_unregister(&sl->dev);
744
745 wait_for_completion(&sl->released);
746 kfree(sl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747}
748
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300749struct w1_master *w1_search_master_id(u32 id)
750{
751 struct w1_master *dev;
752 int found = 0;
753
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400754 mutex_lock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300755 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
756 if (dev->id == id) {
757 found = 1;
758 atomic_inc(&dev->refcnt);
759 break;
760 }
761 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400762 mutex_unlock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300763
764 return (found)?dev:NULL;
765}
766
767struct w1_slave *w1_search_slave(struct w1_reg_num *id)
768{
769 struct w1_master *dev;
770 struct w1_slave *sl = NULL;
771 int found = 0;
772
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400773 mutex_lock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300774 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400775 mutex_lock(&dev->mutex);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300776 list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
777 if (sl->reg_num.family == id->family &&
778 sl->reg_num.id == id->id &&
779 sl->reg_num.crc == id->crc) {
780 found = 1;
781 atomic_inc(&dev->refcnt);
782 atomic_inc(&sl->refcnt);
783 break;
784 }
785 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400786 mutex_unlock(&dev->mutex);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300787
788 if (found)
789 break;
790 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400791 mutex_unlock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300792
793 return (found)?sl:NULL;
794}
795
David Friesc30c9b12008-10-15 22:04:38 -0700796void w1_reconnect_slaves(struct w1_family *f, int attach)
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400797{
David Friesc30c9b12008-10-15 22:04:38 -0700798 struct w1_slave *sl, *sln;
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400799 struct w1_master *dev;
800
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400801 mutex_lock(&w1_mlock);
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400802 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
David Friesc30c9b12008-10-15 22:04:38 -0700803 dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
804 "for family %02x.\n", dev->name, f->fid);
805 mutex_lock(&dev->mutex);
806 list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
807 /* If it is a new family, slaves with the default
808 * family driver and are that family will be
809 * connected. If the family is going away, devices
810 * matching that family are reconneced.
811 */
812 if ((attach && sl->family->fid == W1_FAMILY_DEFAULT
813 && sl->reg_num.family == f->fid) ||
814 (!attach && sl->family->fid == f->fid)) {
815 struct w1_reg_num rn;
816
817 memcpy(&rn, &sl->reg_num, sizeof(rn));
818 w1_slave_detach(sl);
819
820 w1_attach_slave_device(dev, &rn);
821 }
822 }
823 dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
824 "has been finished.\n", dev->name);
825 mutex_unlock(&dev->mutex);
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400826 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400827 mutex_unlock(&w1_mlock);
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400828}
829
David Friesc30c9b12008-10-15 22:04:38 -0700830static void w1_slave_found(struct w1_master *dev, u64 rn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 struct w1_slave *sl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 struct w1_reg_num *tmp;
Evgeniy Polyakov0e65f822005-06-30 22:52:38 +0400834 u64 rn_le = cpu_to_le64(rn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835
David Friesc30c9b12008-10-15 22:04:38 -0700836 atomic_inc(&dev->refcnt);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400837
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 tmp = (struct w1_reg_num *) &rn;
839
David Friescd7b28d2008-10-15 22:04:44 -0700840 sl = w1_slave_search_device(dev, tmp);
841 if (sl) {
842 set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
843 } else {
844 if (rn && tmp->crc == w1_calc_crc8((u8 *)&rn_le, 7))
845 w1_attach_slave_device(dev, tmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 }
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400847
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 atomic_dec(&dev->refcnt);
849}
850
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400851/**
852 * Performs a ROM Search & registers any devices found.
853 * The 1-wire search is a simple binary tree search.
854 * For each bit of the address, we read two bits and write one bit.
855 * The bit written will put to sleep all devies that don't match that bit.
856 * When the two reads differ, the direction choice is obvious.
857 * When both bits are 0, we must choose a path to take.
858 * When we can scan all 64 bits without having to choose a path, we are done.
859 *
860 * See "Application note 187 1-wire search algorithm" at www.maxim-ic.com
861 *
862 * @dev The master device to search
863 * @cb Function to call when a device is found
864 */
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300865void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866{
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400867 u64 last_rn, rn, tmp64;
868 int i, slave_count = 0;
869 int last_zero, last_device;
870 int search_bit, desc_bit;
871 u8 triplet_ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400873 search_bit = 0;
874 rn = last_rn = 0;
875 last_device = 0;
876 last_zero = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877
878 desc_bit = 64;
879
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400880 while ( !last_device && (slave_count++ < dev->max_slave_count) ) {
881 last_rn = rn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 rn = 0;
883
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 /*
885 * Reset bus and all 1-wire device state machines
886 * so they can respond to our requests.
887 *
888 * Return 0 - device(s) present, 1 - no devices present.
889 */
890 if (w1_reset_bus(dev)) {
Evgeniy Polyakov2da5bf82005-08-12 11:46:22 -0700891 dev_dbg(&dev->dev, "No devices present on the wire.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 break;
893 }
894
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400895 /* Start the search */
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300896 w1_write_8(dev, search_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897 for (i = 0; i < 64; ++i) {
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400898 /* Determine the direction/search bit */
899 if (i == desc_bit)
900 search_bit = 1; /* took the 0 path last time, so take the 1 path */
901 else if (i > desc_bit)
902 search_bit = 0; /* take the 0 path on the next branch */
903 else
904 search_bit = ((last_rn >> i) & 0x1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400906 /** Read two bits and write one bit */
907 triplet_ret = w1_triplet(dev, search_bit);
908
909 /* quit if no device responded */
910 if ( (triplet_ret & 0x03) == 0x03 )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911 break;
912
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400913 /* If both directions were valid, and we took the 0 path... */
914 if (triplet_ret == 0)
915 last_zero = i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400917 /* extract the direction taken & update the device number */
918 tmp64 = (triplet_ret >> 2);
919 rn |= (tmp64 << i);
David Fries0d671b22008-10-15 22:04:39 -0700920
David Fries3c52e4e2008-10-15 22:04:41 -0700921 if (kthread_should_stop()) {
David Fries7dc8f522008-10-15 22:04:58 -0700922 dev_dbg(&dev->dev, "Abort w1_search\n");
David Fries0d671b22008-10-15 22:04:39 -0700923 return;
924 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400927 if ( (triplet_ret & 0x03) != 0x03 ) {
928 if ( (desc_bit == last_zero) || (last_zero < 0))
929 last_device = 1;
930 desc_bit = last_zero;
David Friesc30c9b12008-10-15 22:04:38 -0700931 cb(dev, rn);
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400932 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 }
934}
935
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300936void w1_search_process(struct w1_master *dev, u8 search_type)
937{
938 struct w1_slave *sl, *sln;
939
940 list_for_each_entry(sl, &dev->slist, w1_slave_entry)
941 clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
942
943 w1_search_devices(dev, search_type, w1_slave_found);
944
945 list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
Evgeniy Polyakova2a6c742008-01-14 00:55:08 -0800946 if (!test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl)
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300947 w1_slave_detach(sl);
Evgeniy Polyakova2a6c742008-01-14 00:55:08 -0800948 else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags))
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300949 sl->ttl = dev->slave_ttl;
950 }
951
952 if (dev->search_count > 0)
953 dev->search_count--;
954}
955
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956int w1_process(void *data)
957{
958 struct w1_master *dev = (struct w1_master *) data;
David Fries3c52e4e2008-10-15 22:04:41 -0700959 /* As long as w1_timeout is only set by a module parameter the sleep
960 * time can be calculated in jiffies once.
961 */
962 const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963
David Fries3c52e4e2008-10-15 22:04:41 -0700964 while (!kthread_should_stop()) {
David Fries01e14d62008-10-15 22:04:40 -0700965 if (dev->search_count) {
966 mutex_lock(&dev->mutex);
967 w1_search_process(dev, W1_SEARCH);
968 mutex_unlock(&dev->mutex);
969 }
970
Christoph Lameter3e1d1d22005-06-24 23:13:50 -0700971 try_to_freeze();
David Fries3c52e4e2008-10-15 22:04:41 -0700972 __set_current_state(TASK_INTERRUPTIBLE);
973
974 if (kthread_should_stop())
975 break;
976
977 /* Only sleep when the search is active. */
978 if (dev->search_count)
979 schedule_timeout(jtime);
980 else
981 schedule();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982 }
983
984 atomic_dec(&dev->refcnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985
986 return 0;
987}
988
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400989static int w1_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990{
991 int retval;
992
993 printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n");
994
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300995 w1_init_netlink();
996
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 retval = bus_register(&w1_bus_type);
998 if (retval) {
999 printk(KERN_ERR "Failed to register bus. err=%d.\n", retval);
1000 goto err_out_exit_init;
1001 }
1002
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001003 retval = driver_register(&w1_master_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 if (retval) {
1005 printk(KERN_ERR
1006 "Failed to register master driver. err=%d.\n",
1007 retval);
1008 goto err_out_bus_unregister;
1009 }
1010
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001011 retval = driver_register(&w1_slave_driver);
1012 if (retval) {
1013 printk(KERN_ERR
1014 "Failed to register master driver. err=%d.\n",
1015 retval);
1016 goto err_out_master_unregister;
1017 }
1018
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 return 0;
1020
David Friesc30c9b12008-10-15 22:04:38 -07001021#if 0
1022/* For undoing the slave register if there was a step after it. */
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001023err_out_slave_unregister:
1024 driver_unregister(&w1_slave_driver);
David Friesc30c9b12008-10-15 22:04:38 -07001025#endif
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001026
1027err_out_master_unregister:
1028 driver_unregister(&w1_master_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029
1030err_out_bus_unregister:
1031 bus_unregister(&w1_bus_type);
1032
1033err_out_exit_init:
1034 return retval;
1035}
1036
Evgeniy Polyakov77859252005-05-20 22:33:25 +04001037static void w1_fini(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038{
1039 struct w1_master *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040
David Friesc30c9b12008-10-15 22:04:38 -07001041 /* Set netlink removal messages and some cleanup */
Evgeniy Polyakov77859252005-05-20 22:33:25 +04001042 list_for_each_entry(dev, &w1_masters, w1_master_entry)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043 __w1_remove_master_device(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001045 w1_fini_netlink();
1046
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001047 driver_unregister(&w1_slave_driver);
1048 driver_unregister(&w1_master_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 bus_unregister(&w1_bus_type);
1050}
1051
1052module_init(w1_init);
1053module_exit(w1_fini);