blob: 4c89f85edfe693c41b739830283cd2231842aea3 [file] [log] [blame]
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 *
Evgeniy Polyakova8018762011-08-25 15:59:06 -07004 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
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
Arun Sharma600634972011-07-26 16:09:06 -070036#include <linux/atomic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
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");
Evgeniy Polyakova8018762011-08-25 15:59:06 -070045MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
Linus Torvalds1da177e2005-04-16 15:20:36 -070046MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");
47
48static int w1_timeout = 10;
David Friesa1613052014-01-15 22:29:15 -060049int w1_max_slave_count = 64;
Linus Torvalds1da177e2005-04-16 15:20:36 -070050int 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
Greg Kroah-Hartman5b187b32013-08-21 13:24:33 -070099static ssize_t name_show(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}
Greg Kroah-Hartman5b187b32013-08-21 13:24:33 -0700105static DEVICE_ATTR_RO(name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
Greg Kroah-Hartman5b187b32013-08-21 13:24:33 -0700107static ssize_t id_show(struct device *dev,
David Fries07e00342008-10-15 22:04:50 -0700108 struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109{
David Fries07e00342008-10-15 22:04:50 -0700110 struct w1_slave *sl = dev_to_w1_slave(dev);
111 ssize_t count = sizeof(sl->reg_num);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112
David Fries07e00342008-10-15 22:04:50 -0700113 memcpy(buf, (u8 *)&sl->reg_num, count);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400114 return count;
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400115}
Greg Kroah-Hartman5b187b32013-08-21 13:24:33 -0700116static DEVICE_ATTR_RO(id);
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400117
Greg Kroah-Hartman5b187b32013-08-21 13:24:33 -0700118static struct attribute *w1_slave_attrs[] = {
119 &dev_attr_name.attr,
120 &dev_attr_id.attr,
121 NULL,
122};
123ATTRIBUTE_GROUPS(w1_slave);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400124
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400125/* Default family */
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300126
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700127static ssize_t rw_write(struct file *filp, struct kobject *kobj,
128 struct bin_attribute *bin_attr, char *buf, loff_t off,
129 size_t count)
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300130{
131 struct w1_slave *sl = kobj_to_w1_slave(kobj);
132
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400133 mutex_lock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300134 if (w1_reset_select_slave(sl)) {
135 count = 0;
136 goto out_up;
137 }
138
139 w1_write_block(sl->master, buf, count);
140
141out_up:
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400142 mutex_unlock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300143 return count;
144}
145
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700146static ssize_t rw_read(struct file *filp, struct kobject *kobj,
147 struct bin_attribute *bin_attr, char *buf, loff_t off,
148 size_t count)
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300149{
150 struct w1_slave *sl = kobj_to_w1_slave(kobj);
151
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400152 mutex_lock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300153 w1_read_block(sl->master, buf, count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400154 mutex_unlock(&sl->master->mutex);
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300155 return count;
156}
157
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700158static BIN_ATTR_RW(rw, PAGE_SIZE);
159
160static struct bin_attribute *w1_slave_bin_attrs[] = {
161 &bin_attr_rw,
162 NULL,
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300163};
164
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700165static const struct attribute_group w1_slave_default_group = {
166 .bin_attrs = w1_slave_bin_attrs,
167};
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300168
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700169static const struct attribute_group *w1_slave_default_groups[] = {
170 &w1_slave_default_group,
171 NULL,
172};
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300173
174static struct w1_family_ops w1_default_fops = {
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700175 .groups = w1_slave_default_groups,
Evgeniy Polyakovf522d232006-03-23 19:11:58 +0300176};
177
178static struct w1_family w1_default_family = {
179 .fops = &w1_default_fops,
180};
Evgeniy Polyakovd2a4ef62005-08-11 17:27:50 +0400181
Kay Sievers7eff2e72007-08-14 15:15:12 +0200182static int w1_uevent(struct device *dev, struct kobj_uevent_env *env);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400183
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184static struct bus_type w1_bus_type = {
185 .name = "w1",
186 .match = w1_master_match,
Kay Sievers312c0042005-11-16 09:00:00 +0100187 .uevent = w1_uevent,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188};
189
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400190struct device_driver w1_master_driver = {
191 .name = "w1_master_driver",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 .bus = &w1_bus_type,
193 .probe = w1_master_probe,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194};
195
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400196struct device w1_master_device = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 .parent = NULL,
198 .bus = &w1_bus_type,
Kay Sievers40f91de2009-01-06 10:44:34 -0800199 .init_name = "w1 bus master",
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400200 .driver = &w1_master_driver,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 .release = &w1_master_release
202};
203
Evgeniy Polyakov2c5bfda2006-04-04 20:35:22 +0400204static struct device_driver w1_slave_driver = {
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400205 .name = "w1_slave_driver",
206 .bus = &w1_bus_type,
207};
208
Evgeniy Polyakov2c5bfda2006-04-04 20:35:22 +0400209#if 0
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400210struct device w1_slave_device = {
211 .parent = NULL,
212 .bus = &w1_bus_type,
Kay Sievers40f91de2009-01-06 10:44:34 -0800213 .init_name = "w1 bus slave",
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400214 .driver = &w1_slave_driver,
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400215 .release = &w1_slave_release
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400216};
Evgeniy Polyakov2c5bfda2006-04-04 20:35:22 +0400217#endif /* 0 */
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400218
Yani Ioannou060b8842005-05-17 06:44:04 -0400219static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400221 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400223
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400224 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 count = sprintf(buf, "%s\n", md->name);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400226 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227
228 return count;
229}
230
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400231static ssize_t w1_master_attribute_store_search(struct device * dev,
232 struct device_attribute *attr,
233 const char * buf, size_t count)
234{
David Fries6a158c02008-10-15 22:04:42 -0700235 long tmp;
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400236 struct w1_master *md = dev_to_w1_master(dev);
Jingoo Hanbf4228f2013-09-11 14:26:03 -0700237 int ret;
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400238
Jingoo Hanbf4228f2013-09-11 14:26:03 -0700239 ret = kstrtol(buf, 0, &tmp);
240 if (ret)
241 return ret;
David Fries6a158c02008-10-15 22:04:42 -0700242
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400243 mutex_lock(&md->mutex);
David Fries6a158c02008-10-15 22:04:42 -0700244 md->search_count = tmp;
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400245 mutex_unlock(&md->mutex);
David Friesaf8c7232014-01-15 22:29:14 -0600246 /* Only wake if it is going to be searching. */
247 if (tmp)
248 wake_up_process(md->thread);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400249
250 return count;
251}
252
253static ssize_t w1_master_attribute_show_search(struct device *dev,
254 struct device_attribute *attr,
255 char *buf)
256{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400257 struct w1_master *md = dev_to_w1_master(dev);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400258 ssize_t count;
259
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400260 mutex_lock(&md->mutex);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400261 count = sprintf(buf, "%d\n", md->search_count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400262 mutex_unlock(&md->mutex);
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400263
264 return count;
265}
266
David Fries6a158c02008-10-15 22:04:42 -0700267static ssize_t w1_master_attribute_store_pullup(struct device *dev,
268 struct device_attribute *attr,
269 const char *buf, size_t count)
270{
271 long tmp;
272 struct w1_master *md = dev_to_w1_master(dev);
Jingoo Hanbf4228f2013-09-11 14:26:03 -0700273 int ret;
David Fries6a158c02008-10-15 22:04:42 -0700274
Jingoo Hanbf4228f2013-09-11 14:26:03 -0700275 ret = kstrtol(buf, 0, &tmp);
276 if (ret)
277 return ret;
David Fries6a158c02008-10-15 22:04:42 -0700278
279 mutex_lock(&md->mutex);
280 md->enable_pullup = tmp;
281 mutex_unlock(&md->mutex);
282 wake_up_process(md->thread);
283
284 return count;
285}
286
287static ssize_t w1_master_attribute_show_pullup(struct device *dev,
288 struct device_attribute *attr,
289 char *buf)
290{
291 struct w1_master *md = dev_to_w1_master(dev);
292 ssize_t count;
293
294 mutex_lock(&md->mutex);
295 count = sprintf(buf, "%d\n", md->enable_pullup);
296 mutex_unlock(&md->mutex);
297
298 return count;
299}
300
Yani Ioannou060b8842005-05-17 06:44:04 -0400301static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400303 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400305
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400306 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 count = sprintf(buf, "0x%p\n", md->bus_master);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400308 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 return count;
310}
311
Yani Ioannou060b8842005-05-17 06:44:04 -0400312static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313{
314 ssize_t count;
315 count = sprintf(buf, "%d\n", w1_timeout);
316 return count;
317}
318
David Friesa1613052014-01-15 22:29:15 -0600319static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev,
320 struct device_attribute *attr, const char *buf, size_t count)
321{
322 long tmp;
323 struct w1_master *md = dev_to_w1_master(dev);
324
325 if (kstrtol(buf, 0, &tmp) == -EINVAL || tmp < 1)
326 return -EINVAL;
327
328 mutex_lock(&md->mutex);
329 md->max_slave_count = tmp;
330 /* allow each time the max_slave_count is updated */
331 clear_bit(W1_WARN_MAX_COUNT, &md->flags);
332 mutex_unlock(&md->mutex);
333
334 return count;
335}
336
Yani Ioannou060b8842005-05-17 06:44:04 -0400337static 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 -0700338{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400339 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400341
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400342 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 count = sprintf(buf, "%d\n", md->max_slave_count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400344 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 return count;
346}
347
Yani Ioannou060b8842005-05-17 06:44:04 -0400348static ssize_t w1_master_attribute_show_attempts(struct device *dev, 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 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400352
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400353 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 count = sprintf(buf, "%lu\n", md->attempts);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400355 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 return count;
357}
358
Yani Ioannou060b8842005-05-17 06:44:04 -0400359static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400361 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 ssize_t count;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400363
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400364 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 count = sprintf(buf, "%d\n", md->slave_count);
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400366 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 return count;
368}
369
David Fries9b467412008-10-15 22:04:43 -0700370static ssize_t w1_master_attribute_show_slaves(struct device *dev,
371 struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372{
Evgeniy Polyakovdb2d0002005-08-11 17:27:49 +0400373 struct w1_master *md = dev_to_w1_master(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 int c = PAGE_SIZE;
375
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400376 mutex_lock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
378 if (md->slave_count == 0)
379 c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
380 else {
381 struct list_head *ent, *n;
382 struct w1_slave *sl;
383
384 list_for_each_safe(ent, n, &md->slist) {
385 sl = list_entry(ent, struct w1_slave, w1_slave_entry);
386
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400387 c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 }
389 }
390
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400391 mutex_unlock(&md->mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
393 return PAGE_SIZE - c;
394}
395
David Fries9b467412008-10-15 22:04:43 -0700396static ssize_t w1_master_attribute_show_add(struct device *dev,
397 struct device_attribute *attr, char *buf)
398{
399 int c = PAGE_SIZE;
400 c -= snprintf(buf+PAGE_SIZE - c, c,
401 "write device id xx-xxxxxxxxxxxx to add slave\n");
402 return PAGE_SIZE - c;
403}
404
405static int w1_atoreg_num(struct device *dev, const char *buf, size_t count,
406 struct w1_reg_num *rn)
407{
408 unsigned int family;
409 unsigned long long id;
410 int i;
411 u64 rn64_le;
412
413 /* The CRC value isn't read from the user because the sysfs directory
414 * doesn't include it and most messages from the bus search don't
415 * print it either. It would be unreasonable for the user to then
416 * provide it.
417 */
418 const char *error_msg = "bad slave string format, expecting "
419 "ff-dddddddddddd\n";
420
421 if (buf[2] != '-') {
422 dev_err(dev, "%s", error_msg);
423 return -EINVAL;
424 }
425 i = sscanf(buf, "%02x-%012llx", &family, &id);
426 if (i != 2) {
427 dev_err(dev, "%s", error_msg);
428 return -EINVAL;
429 }
430 rn->family = family;
431 rn->id = id;
432
433 rn64_le = cpu_to_le64(*(u64 *)rn);
434 rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7);
435
436#if 0
437 dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n",
438 rn->family, (unsigned long long)rn->id, rn->crc);
439#endif
440
441 return 0;
442}
443
444/* Searches the slaves in the w1_master and returns a pointer or NULL.
445 * Note: must hold the mutex
446 */
447static struct w1_slave *w1_slave_search_device(struct w1_master *dev,
448 struct w1_reg_num *rn)
449{
450 struct w1_slave *sl;
451 list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
452 if (sl->reg_num.family == rn->family &&
453 sl->reg_num.id == rn->id &&
454 sl->reg_num.crc == rn->crc) {
455 return sl;
456 }
457 }
458 return NULL;
459}
460
461static ssize_t w1_master_attribute_store_add(struct device *dev,
462 struct device_attribute *attr,
463 const char *buf, size_t count)
464{
465 struct w1_master *md = dev_to_w1_master(dev);
466 struct w1_reg_num rn;
467 struct w1_slave *sl;
468 ssize_t result = count;
469
470 if (w1_atoreg_num(dev, buf, count, &rn))
471 return -EINVAL;
472
473 mutex_lock(&md->mutex);
474 sl = w1_slave_search_device(md, &rn);
475 /* It would be nice to do a targeted search one the one-wire bus
476 * for the new device to see if it is out there or not. But the
477 * current search doesn't support that.
478 */
479 if (sl) {
480 dev_info(dev, "Device %s already exists\n", sl->name);
481 result = -EINVAL;
482 } else {
483 w1_attach_slave_device(md, &rn);
484 }
485 mutex_unlock(&md->mutex);
486
487 return result;
488}
489
490static ssize_t w1_master_attribute_show_remove(struct device *dev,
491 struct device_attribute *attr, char *buf)
492{
493 int c = PAGE_SIZE;
494 c -= snprintf(buf+PAGE_SIZE - c, c,
495 "write device id xx-xxxxxxxxxxxx to remove slave\n");
496 return PAGE_SIZE - c;
497}
498
499static ssize_t w1_master_attribute_store_remove(struct device *dev,
500 struct device_attribute *attr,
501 const char *buf, size_t count)
502{
503 struct w1_master *md = dev_to_w1_master(dev);
504 struct w1_reg_num rn;
505 struct w1_slave *sl;
506 ssize_t result = count;
507
508 if (w1_atoreg_num(dev, buf, count, &rn))
509 return -EINVAL;
510
511 mutex_lock(&md->mutex);
512 sl = w1_slave_search_device(md, &rn);
513 if (sl) {
514 w1_slave_detach(sl);
515 } else {
516 dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family,
517 (unsigned long long)rn.id);
518 result = -EINVAL;
519 }
520 mutex_unlock(&md->mutex);
521
522 return result;
523}
524
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400525#define W1_MASTER_ATTR_RO(_name, _mode) \
526 struct device_attribute w1_master_attribute_##_name = \
527 __ATTR(w1_master_##_name, _mode, \
528 w1_master_attribute_show_##_name, NULL)
529
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400530#define W1_MASTER_ATTR_RW(_name, _mode) \
531 struct device_attribute w1_master_attribute_##_name = \
532 __ATTR(w1_master_##_name, _mode, \
533 w1_master_attribute_show_##_name, \
534 w1_master_attribute_store_##_name)
535
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400536static W1_MASTER_ATTR_RO(name, S_IRUGO);
537static W1_MASTER_ATTR_RO(slaves, S_IRUGO);
538static W1_MASTER_ATTR_RO(slave_count, S_IRUGO);
David Friesa1613052014-01-15 22:29:15 -0600539static W1_MASTER_ATTR_RW(max_slave_count, S_IRUGO | S_IWUSR | S_IWGRP);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400540static W1_MASTER_ATTR_RO(attempts, S_IRUGO);
541static W1_MASTER_ATTR_RO(timeout, S_IRUGO);
542static W1_MASTER_ATTR_RO(pointer, S_IRUGO);
Brian Swetland12aa4c62010-10-27 15:34:49 -0700543static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUSR | S_IWGRP);
544static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUSR | S_IWGRP);
545static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUSR | S_IWGRP);
546static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUSR | S_IWGRP);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400547
548static struct attribute *w1_master_default_attrs[] = {
549 &w1_master_attribute_name.attr,
550 &w1_master_attribute_slaves.attr,
551 &w1_master_attribute_slave_count.attr,
552 &w1_master_attribute_max_slave_count.attr,
553 &w1_master_attribute_attempts.attr,
554 &w1_master_attribute_timeout.attr,
555 &w1_master_attribute_pointer.attr,
Evgeniy Polyakov2a9d0c12005-06-04 01:31:02 +0400556 &w1_master_attribute_search.attr,
David Fries6a158c02008-10-15 22:04:42 -0700557 &w1_master_attribute_pullup.attr,
David Fries9b467412008-10-15 22:04:43 -0700558 &w1_master_attribute_add.attr,
559 &w1_master_attribute_remove.attr,
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400560 NULL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561};
562
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400563static struct attribute_group w1_master_defattr_group = {
564 .attrs = w1_master_default_attrs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565};
566
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400567int w1_create_master_attributes(struct w1_master *master)
568{
569 return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group);
570}
571
David Friesc30c9b12008-10-15 22:04:38 -0700572void w1_destroy_master_attributes(struct w1_master *master)
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400573{
574 sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group);
575}
576
Kay Sievers7eff2e72007-08-14 15:15:12 +0200577static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400578{
579 struct w1_master *md = NULL;
580 struct w1_slave *sl = NULL;
581 char *event_owner, *name;
Devendra Naga526be412012-05-19 07:31:54 +0400582 int err = 0;
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400583
584 if (dev->driver == &w1_master_driver) {
585 md = container_of(dev, struct w1_master, dev);
586 event_owner = "master";
587 name = md->name;
588 } else if (dev->driver == &w1_slave_driver) {
589 sl = container_of(dev, struct w1_slave, dev);
590 event_owner = "slave";
591 name = sl->name;
592 } else {
Kay Sievers312c0042005-11-16 09:00:00 +0100593 dev_dbg(dev, "Unknown event.\n");
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400594 return -EINVAL;
595 }
596
Andrew Mortonc6976a42006-05-14 21:43:50 -0700597 dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800598 event_owner, name, dev_name(dev));
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400599
600 if (dev->driver != &w1_slave_driver || !sl)
Devendra Naga526be412012-05-19 07:31:54 +0400601 goto end;
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400602
Kay Sievers7eff2e72007-08-14 15:15:12 +0200603 err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family);
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400604 if (err)
Devendra Naga526be412012-05-19 07:31:54 +0400605 goto end;
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400606
Kay Sievers7eff2e72007-08-14 15:15:12 +0200607 err = add_uevent_var(env, "W1_SLAVE_ID=%024LX",
608 (unsigned long long)sl->reg_num.id);
Devendra Naga526be412012-05-19 07:31:54 +0400609end:
610 return err;
611}
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400612
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700613/*
614 * Handle sysfs file creation and removal here, before userspace is told that
615 * the device is added / removed from the system
616 */
617static int w1_bus_notify(struct notifier_block *nb, unsigned long action,
618 void *data)
619{
620 struct device *dev = data;
621 struct w1_slave *sl;
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700622 struct w1_family_ops *fops;
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700623 int err;
624
625 /*
626 * Only care about slave devices at the moment. Yes, we should use a
627 * separate "type" for this, but for now, look at the release function
628 * to know which type it is...
629 */
630 if (dev->release != w1_slave_release)
631 return 0;
632
633 sl = dev_to_w1_slave(dev);
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700634 fops = sl->family->fops;
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700635
Hans-Frieder Vogt2962aec2013-10-06 21:13:35 +0200636 if (!fops)
637 return 0;
638
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700639 switch (action) {
640 case BUS_NOTIFY_ADD_DEVICE:
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700641 /* if the family driver needs to initialize something... */
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700642 if (fops->add_slave) {
643 err = fops->add_slave(sl);
644 if (err < 0) {
645 dev_err(&sl->dev,
646 "add_slave() call failed. err=%d\n",
647 err);
648 return err;
649 }
650 }
651 if (fops->groups) {
652 err = sysfs_create_groups(&sl->dev.kobj, fops->groups);
653 if (err) {
654 dev_err(&sl->dev,
655 "sysfs group creation failed. err=%d\n",
656 err);
657 return err;
658 }
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700659 }
660
661 break;
662 case BUS_NOTIFY_DEL_DEVICE:
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700663 if (fops->remove_slave)
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700664 sl->family->fops->remove_slave(sl);
Greg Kroah-Hartman36c27a62013-08-21 15:44:55 -0700665 if (fops->groups)
666 sysfs_remove_groups(&sl->dev.kobj, fops->groups);
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700667 break;
668 }
669 return 0;
670}
671
672static struct notifier_block w1_bus_nb = {
673 .notifier_call = w1_bus_notify,
674};
675
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676static int __w1_attach_slave_device(struct w1_slave *sl)
677{
678 int err;
679
680 sl->dev.parent = &sl->master->dev;
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +0400681 sl->dev.driver = &w1_slave_driver;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 sl->dev.bus = &w1_bus_type;
683 sl->dev.release = &w1_slave_release;
Greg Kroah-Hartman5b187b32013-08-21 13:24:33 -0700684 sl->dev.groups = w1_slave_groups;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685
Kay Sievers40f91de2009-01-06 10:44:34 -0800686 dev_set_name(&sl->dev, "%02x-%012llx",
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400687 (unsigned int) sl->reg_num.family,
688 (unsigned long long) sl->reg_num.id);
689 snprintf(&sl->name[0], sizeof(sl->name),
690 "%02x-%012llx",
691 (unsigned int) sl->reg_num.family,
692 (unsigned long long) sl->reg_num.id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693
Andrew Mortonc6976a42006-05-14 21:43:50 -0700694 dev_dbg(&sl->dev, "%s: registering %s as %p.\n", __func__,
Kay Sievers40f91de2009-01-06 10:44:34 -0800695 dev_name(&sl->dev), sl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696
697 err = device_register(&sl->dev);
698 if (err < 0) {
699 dev_err(&sl->dev,
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400700 "Device registration [%s] failed. err=%d\n",
Kay Sievers40f91de2009-01-06 10:44:34 -0800701 dev_name(&sl->dev), err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 return err;
703 }
704
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -0700706 dev_set_uevent_suppress(&sl->dev, false);
707 kobject_uevent(&sl->dev.kobj, KOBJ_ADD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708
709 list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
710
711 return 0;
712}
713
714static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
715{
716 struct w1_slave *sl;
717 struct w1_family *f;
718 int err;
719 struct w1_netlink_msg msg;
720
Yoann Padioleaudd00cc42007-07-19 01:49:03 -0700721 sl = kzalloc(sizeof(struct w1_slave), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722 if (!sl) {
723 dev_err(&dev->dev,
724 "%s: failed to allocate new slave device.\n",
725 __func__);
726 return -ENOMEM;
727 }
728
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729
730 sl->owner = THIS_MODULE;
731 sl->master = dev;
Michal Nazarewiczbb670932013-11-12 15:11:42 -0800732 set_bit(W1_SLAVE_ACTIVE, &sl->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300734 memset(&msg, 0, sizeof(msg));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735 memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
736 atomic_set(&sl->refcnt, 0);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400737 init_completion(&sl->released);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738
Hans-Frieder Vogtbc04d762013-10-06 21:13:40 +0200739 /* slave modules need to be loaded in a context with unlocked mutex */
740 mutex_unlock(&dev->mutex);
Alexander Stein8d7bda52013-05-26 20:06:50 +0200741 request_module("w1-family-0x%0x", rn->family);
Hans-Frieder Vogtbc04d762013-10-06 21:13:40 +0200742 mutex_lock(&dev->mutex);
Alexander Stein8d7bda52013-05-26 20:06:50 +0200743
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 spin_lock(&w1_flock);
745 f = w1_family_registered(rn->family);
746 if (!f) {
Evgeniy Polyakov99c5bfe2005-06-04 01:31:26 +0400747 f= &w1_default_family;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n",
749 rn->family, rn->family,
750 (unsigned long long)rn->id, rn->crc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751 }
752 __w1_family_get(f);
753 spin_unlock(&w1_flock);
754
755 sl->family = f;
756
757
758 err = __w1_attach_slave_device(sl);
759 if (err < 0) {
760 dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__,
761 sl->name);
762 w1_family_put(sl->family);
763 kfree(sl);
764 return err;
765 }
766
767 sl->ttl = dev->slave_ttl;
768 dev->slave_count++;
769
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300770 memcpy(msg.id.id, rn, sizeof(msg.id));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 msg.type = W1_SLAVE_ADD;
772 w1_netlink_send(dev, &msg);
773
774 return 0;
775}
776
David Friesc30c9b12008-10-15 22:04:38 -0700777void w1_slave_detach(struct w1_slave *sl)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778{
779 struct w1_netlink_msg msg;
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400780
Evgeniy Polyakov7c8f5702005-08-11 17:27:50 +0400781 dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__, sl->name, sl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400783 list_del(&sl->w1_slave_entry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300785 memset(&msg, 0, sizeof(msg));
786 memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787 msg.type = W1_SLAVE_REMOVE;
788 w1_netlink_send(sl->master, &msg);
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400789
Evgeniy Polyakov3aca6922005-08-11 17:27:50 +0400790 device_unregister(&sl->dev);
791
792 wait_for_completion(&sl->released);
793 kfree(sl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794}
795
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300796struct w1_master *w1_search_master_id(u32 id)
797{
798 struct w1_master *dev;
799 int found = 0;
800
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400801 mutex_lock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300802 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
803 if (dev->id == id) {
804 found = 1;
805 atomic_inc(&dev->refcnt);
806 break;
807 }
808 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400809 mutex_unlock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300810
811 return (found)?dev:NULL;
812}
813
814struct w1_slave *w1_search_slave(struct w1_reg_num *id)
815{
816 struct w1_master *dev;
817 struct w1_slave *sl = NULL;
818 int found = 0;
819
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400820 mutex_lock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300821 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400822 mutex_lock(&dev->mutex);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300823 list_for_each_entry(sl, &dev->slist, w1_slave_entry) {
824 if (sl->reg_num.family == id->family &&
825 sl->reg_num.id == id->id &&
826 sl->reg_num.crc == id->crc) {
827 found = 1;
828 atomic_inc(&dev->refcnt);
829 atomic_inc(&sl->refcnt);
830 break;
831 }
832 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400833 mutex_unlock(&dev->mutex);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300834
835 if (found)
836 break;
837 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400838 mutex_unlock(&w1_mlock);
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300839
840 return (found)?sl:NULL;
841}
842
David Friesc30c9b12008-10-15 22:04:38 -0700843void w1_reconnect_slaves(struct w1_family *f, int attach)
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400844{
David Friesc30c9b12008-10-15 22:04:38 -0700845 struct w1_slave *sl, *sln;
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400846 struct w1_master *dev;
847
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400848 mutex_lock(&w1_mlock);
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400849 list_for_each_entry(dev, &w1_masters, w1_master_entry) {
David Friesc30c9b12008-10-15 22:04:38 -0700850 dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
851 "for family %02x.\n", dev->name, f->fid);
852 mutex_lock(&dev->mutex);
853 list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
854 /* If it is a new family, slaves with the default
855 * family driver and are that family will be
856 * connected. If the family is going away, devices
857 * matching that family are reconneced.
858 */
859 if ((attach && sl->family->fid == W1_FAMILY_DEFAULT
860 && sl->reg_num.family == f->fid) ||
861 (!attach && sl->family->fid == f->fid)) {
862 struct w1_reg_num rn;
863
864 memcpy(&rn, &sl->reg_num, sizeof(rn));
865 w1_slave_detach(sl);
866
867 w1_attach_slave_device(dev, &rn);
868 }
869 }
870 dev_dbg(&dev->dev, "Reconnecting slaves in device %s "
871 "has been finished.\n", dev->name);
872 mutex_unlock(&dev->mutex);
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400873 }
Evgeniy Polyakovabd52a12006-04-03 12:04:27 +0400874 mutex_unlock(&w1_mlock);
Evgeniy Polyakov6adf87b2005-06-04 01:29:25 +0400875}
876
David Fries963bb102011-05-26 16:26:03 -0700877void w1_slave_found(struct w1_master *dev, u64 rn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 struct w1_slave *sl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 struct w1_reg_num *tmp;
Evgeniy Polyakov0e65f822005-06-30 22:52:38 +0400881 u64 rn_le = cpu_to_le64(rn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882
David Friesc30c9b12008-10-15 22:04:38 -0700883 atomic_inc(&dev->refcnt);
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400884
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 tmp = (struct w1_reg_num *) &rn;
886
David Friescd7b28d2008-10-15 22:04:44 -0700887 sl = w1_slave_search_device(dev, tmp);
888 if (sl) {
Michal Nazarewiczbb670932013-11-12 15:11:42 -0800889 set_bit(W1_SLAVE_ACTIVE, &sl->flags);
David Friescd7b28d2008-10-15 22:04:44 -0700890 } else {
891 if (rn && tmp->crc == w1_calc_crc8((u8 *)&rn_le, 7))
892 w1_attach_slave_device(dev, tmp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 }
Evgeniy Polyakov77859252005-05-20 22:33:25 +0400894
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 atomic_dec(&dev->refcnt);
896}
897
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400898/**
899 * Performs a ROM Search & registers any devices found.
900 * The 1-wire search is a simple binary tree search.
901 * For each bit of the address, we read two bits and write one bit.
902 * The bit written will put to sleep all devies that don't match that bit.
903 * When the two reads differ, the direction choice is obvious.
904 * When both bits are 0, we must choose a path to take.
905 * When we can scan all 64 bits without having to choose a path, we are done.
906 *
907 * See "Application note 187 1-wire search algorithm" at www.maxim-ic.com
908 *
909 * @dev The master device to search
910 * @cb Function to call when a device is found
911 */
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300912void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913{
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400914 u64 last_rn, rn, tmp64;
915 int i, slave_count = 0;
916 int last_zero, last_device;
917 int search_bit, desc_bit;
918 u8 triplet_ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400920 search_bit = 0;
David Fries3c6955e2014-01-15 22:29:16 -0600921 rn = dev->search_id;
922 last_rn = 0;
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400923 last_device = 0;
924 last_zero = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925
926 desc_bit = 64;
927
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400928 while ( !last_device && (slave_count++ < dev->max_slave_count) ) {
929 last_rn = rn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 rn = 0;
931
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 /*
933 * Reset bus and all 1-wire device state machines
934 * so they can respond to our requests.
935 *
936 * Return 0 - device(s) present, 1 - no devices present.
937 */
NeilBrownb02f8be2012-05-18 15:59:52 +1000938 mutex_lock(&dev->bus_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939 if (w1_reset_bus(dev)) {
NeilBrownb02f8be2012-05-18 15:59:52 +1000940 mutex_unlock(&dev->bus_mutex);
Evgeniy Polyakov2da5bf82005-08-12 11:46:22 -0700941 dev_dbg(&dev->dev, "No devices present on the wire.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 break;
943 }
944
Evgeniy Polyakovc9cbf552011-12-10 04:36:11 +0300945 /* Do fast search on single slave bus */
946 if (dev->max_slave_count == 1) {
NeilBrownb02f8be2012-05-18 15:59:52 +1000947 int rv;
Evgeniy Polyakovc9cbf552011-12-10 04:36:11 +0300948 w1_write_8(dev, W1_READ_ROM);
NeilBrownb02f8be2012-05-18 15:59:52 +1000949 rv = w1_read_block(dev, (u8 *)&rn, 8);
950 mutex_unlock(&dev->bus_mutex);
Evgeniy Polyakovc9cbf552011-12-10 04:36:11 +0300951
NeilBrownb02f8be2012-05-18 15:59:52 +1000952 if (rv == 8 && rn)
Evgeniy Polyakovc9cbf552011-12-10 04:36:11 +0300953 cb(dev, rn);
954
955 break;
956 }
957
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400958 /* Start the search */
Evgeniy Polyakov12003372006-03-23 19:11:58 +0300959 w1_write_8(dev, search_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960 for (i = 0; i < 64; ++i) {
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400961 /* Determine the direction/search bit */
962 if (i == desc_bit)
963 search_bit = 1; /* took the 0 path last time, so take the 1 path */
964 else if (i > desc_bit)
965 search_bit = 0; /* take the 0 path on the next branch */
966 else
967 search_bit = ((last_rn >> i) & 0x1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400969 /** Read two bits and write one bit */
970 triplet_ret = w1_triplet(dev, search_bit);
971
972 /* quit if no device responded */
973 if ( (triplet_ret & 0x03) == 0x03 )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 break;
975
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400976 /* If both directions were valid, and we took the 0 path... */
977 if (triplet_ret == 0)
978 last_zero = i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400980 /* extract the direction taken & update the device number */
981 tmp64 = (triplet_ret >> 2);
982 rn |= (tmp64 << i);
David Fries0d671b22008-10-15 22:04:39 -0700983
David Fries42105692014-01-15 22:29:13 -0600984 if (test_bit(W1_ABORT_SEARCH, &dev->flags)) {
NeilBrownb02f8be2012-05-18 15:59:52 +1000985 mutex_unlock(&dev->bus_mutex);
David Fries7dc8f522008-10-15 22:04:58 -0700986 dev_dbg(&dev->dev, "Abort w1_search\n");
David Fries0d671b22008-10-15 22:04:39 -0700987 return;
988 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989 }
NeilBrownb02f8be2012-05-18 15:59:52 +1000990 mutex_unlock(&dev->bus_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400992 if ( (triplet_ret & 0x03) != 0x03 ) {
David Fries3c6955e2014-01-15 22:29:16 -0600993 if ((desc_bit == last_zero) || (last_zero < 0)) {
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400994 last_device = 1;
David Fries3c6955e2014-01-15 22:29:16 -0600995 dev->search_id = 0;
996 } else {
997 dev->search_id = rn;
998 }
Evgeniy Polyakov6b729862005-06-04 01:30:43 +0400999 desc_bit = last_zero;
David Friesc30c9b12008-10-15 22:04:38 -07001000 cb(dev, rn);
Evgeniy Polyakov6b729862005-06-04 01:30:43 +04001001 }
David Friesa1613052014-01-15 22:29:15 -06001002
1003 if (!last_device && slave_count == dev->max_slave_count &&
1004 !test_bit(W1_WARN_MAX_COUNT, &dev->flags)) {
David Fries3c6955e2014-01-15 22:29:16 -06001005 /* Only max_slave_count will be scanned in a search,
1006 * but it will start where it left off next search
1007 * until all ids are identified and then it will start
1008 * over. A continued search will report the previous
1009 * last id as the first id (provided it is still on the
1010 * bus).
1011 */
David Friesa1613052014-01-15 22:29:15 -06001012 dev_info(&dev->dev, "%s: max_slave_count %d reached, "
David Fries3c6955e2014-01-15 22:29:16 -06001013 "will continue next search.\n", __func__,
David Friesa1613052014-01-15 22:29:15 -06001014 dev->max_slave_count);
1015 set_bit(W1_WARN_MAX_COUNT, &dev->flags);
1016 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017 }
1018}
1019
David Fries963bb102011-05-26 16:26:03 -07001020void w1_search_process_cb(struct w1_master *dev, u8 search_type,
1021 w1_slave_found_callback cb)
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001022{
1023 struct w1_slave *sl, *sln;
1024
1025 list_for_each_entry(sl, &dev->slist, w1_slave_entry)
Michal Nazarewiczbb670932013-11-12 15:11:42 -08001026 clear_bit(W1_SLAVE_ACTIVE, &sl->flags);
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001027
David Fries963bb102011-05-26 16:26:03 -07001028 w1_search_devices(dev, search_type, cb);
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001029
1030 list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
Michal Nazarewiczbb670932013-11-12 15:11:42 -08001031 if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl)
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001032 w1_slave_detach(sl);
Michal Nazarewiczbb670932013-11-12 15:11:42 -08001033 else if (test_bit(W1_SLAVE_ACTIVE, &sl->flags))
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001034 sl->ttl = dev->slave_ttl;
1035 }
1036
1037 if (dev->search_count > 0)
1038 dev->search_count--;
1039}
1040
David Fries963bb102011-05-26 16:26:03 -07001041static void w1_search_process(struct w1_master *dev, u8 search_type)
1042{
1043 w1_search_process_cb(dev, search_type, w1_slave_found);
1044}
1045
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046int w1_process(void *data)
1047{
1048 struct w1_master *dev = (struct w1_master *) data;
David Fries3c52e4e2008-10-15 22:04:41 -07001049 /* As long as w1_timeout is only set by a module parameter the sleep
1050 * time can be calculated in jiffies once.
1051 */
1052 const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053
David Fries3c52e4e2008-10-15 22:04:41 -07001054 while (!kthread_should_stop()) {
David Fries01e14d62008-10-15 22:04:40 -07001055 if (dev->search_count) {
1056 mutex_lock(&dev->mutex);
1057 w1_search_process(dev, W1_SEARCH);
1058 mutex_unlock(&dev->mutex);
1059 }
1060
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001061 try_to_freeze();
David Fries3c52e4e2008-10-15 22:04:41 -07001062 __set_current_state(TASK_INTERRUPTIBLE);
1063
1064 if (kthread_should_stop())
1065 break;
1066
1067 /* Only sleep when the search is active. */
1068 if (dev->search_count)
1069 schedule_timeout(jtime);
1070 else
1071 schedule();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 }
1073
1074 atomic_dec(&dev->refcnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075
1076 return 0;
1077}
1078
Peter Huewe73a98fc2009-12-22 09:38:02 +01001079static int __init w1_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080{
1081 int retval;
1082
1083 printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n");
1084
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001085 w1_init_netlink();
1086
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 retval = bus_register(&w1_bus_type);
1088 if (retval) {
1089 printk(KERN_ERR "Failed to register bus. err=%d.\n", retval);
1090 goto err_out_exit_init;
1091 }
1092
Greg Kroah-Hartman47eba332013-08-21 13:24:32 -07001093 retval = bus_register_notifier(&w1_bus_type, &w1_bus_nb);
1094 if (retval)
1095 goto err_out_bus_unregister;
1096
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001097 retval = driver_register(&w1_master_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098 if (retval) {
1099 printk(KERN_ERR
1100 "Failed to register master driver. err=%d.\n",
1101 retval);
1102 goto err_out_bus_unregister;
1103 }
1104
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001105 retval = driver_register(&w1_slave_driver);
1106 if (retval) {
1107 printk(KERN_ERR
Dmitry Artamonowecf19482012-04-02 09:42:22 +04001108 "Failed to register slave driver. err=%d.\n",
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001109 retval);
1110 goto err_out_master_unregister;
1111 }
1112
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 return 0;
1114
David Friesc30c9b12008-10-15 22:04:38 -07001115#if 0
1116/* For undoing the slave register if there was a step after it. */
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001117err_out_slave_unregister:
1118 driver_unregister(&w1_slave_driver);
David Friesc30c9b12008-10-15 22:04:38 -07001119#endif
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001120
1121err_out_master_unregister:
1122 driver_unregister(&w1_master_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001123
1124err_out_bus_unregister:
1125 bus_unregister(&w1_bus_type);
1126
1127err_out_exit_init:
1128 return retval;
1129}
1130
Peter Huewe73a98fc2009-12-22 09:38:02 +01001131static void __exit w1_fini(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001132{
1133 struct w1_master *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134
David Friesc30c9b12008-10-15 22:04:38 -07001135 /* Set netlink removal messages and some cleanup */
Evgeniy Polyakov77859252005-05-20 22:33:25 +04001136 list_for_each_entry(dev, &w1_masters, w1_master_entry)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 __w1_remove_master_device(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138
Evgeniy Polyakov12003372006-03-23 19:11:58 +03001139 w1_fini_netlink();
1140
Evgeniy Polyakov7f772ed2005-08-11 13:20:07 +04001141 driver_unregister(&w1_slave_driver);
1142 driver_unregister(&w1_master_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143 bus_unregister(&w1_bus_type);
1144}
1145
1146module_init(w1_init);
1147module_exit(w1_fini);