Commit | Line | Data |
---|---|---|
c942fddf | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 | 2 | /* |
a8018766 | 3 | * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> |
1da177e4 LT |
4 | */ |
5 | ||
6 | #include <linux/delay.h> | |
7 | #include <linux/kernel.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/moduleparam.h> | |
10 | #include <linux/list.h> | |
11 | #include <linux/interrupt.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/timer.h> | |
14 | #include <linux/device.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/sched.h> | |
674a396c | 17 | #include <linux/kthread.h> |
7dfb7103 | 18 | #include <linux/freezer.h> |
2eb79548 | 19 | #include <linux/hwmon.h> |
fae68031 | 20 | #include <linux/of.h> |
1da177e4 | 21 | |
60063497 | 22 | #include <linux/atomic.h> |
1da177e4 | 23 | |
de0d6dbd | 24 | #include "w1_internal.h" |
1da177e4 LT |
25 | #include "w1_netlink.h" |
26 | ||
de0d6dbd | 27 | #define W1_FAMILY_DEFAULT 0 |
48b7de66 CV |
28 | #define W1_FAMILY_DS28E04 0x1C /* for crc quirk */ |
29 | ||
de0d6dbd | 30 | |
1da177e4 | 31 | static int w1_timeout = 10; |
1da177e4 | 32 | module_param_named(timeout, w1_timeout, int, 0); |
b3be177a | 33 | MODULE_PARM_DESC(timeout, "time in seconds between automatic slave searches"); |
50fa2951 AD |
34 | |
35 | static int w1_timeout_us = 0; | |
c3098356 | 36 | module_param_named(timeout_us, w1_timeout_us, int, 0); |
a46b195c WY |
37 | MODULE_PARM_DESC(timeout_us, |
38 | "time in microseconds between automatic slave searches"); | |
50fa2951 | 39 | |
b3be177a DF |
40 | /* A search stops when w1_max_slave_count devices have been found in that |
41 | * search. The next search will start over and detect the same set of devices | |
42 | * on a static 1-wire bus. Memory is not allocated based on this number, just | |
43 | * on the number of devices known to the kernel. Having a high number does not | |
44 | * consume additional resources. As a special case, if there is only one | |
45 | * device on the network and w1_max_slave_count is set to 1, the device id can | |
46 | * be read directly skipping the normal slower search process. | |
47 | */ | |
50fa2951 | 48 | int w1_max_slave_count = 64; |
1da177e4 | 49 | module_param_named(max_slave_count, w1_max_slave_count, int, 0); |
b3be177a DF |
50 | MODULE_PARM_DESC(max_slave_count, |
51 | "maximum number of slaves detected in a search"); | |
50fa2951 AD |
52 | |
53 | int w1_max_slave_ttl = 10; | |
1da177e4 | 54 | module_param_named(slave_ttl, w1_max_slave_ttl, int, 0); |
b3be177a DF |
55 | MODULE_PARM_DESC(slave_ttl, |
56 | "Number of searches not seeing a slave before it will be removed"); | |
1da177e4 | 57 | |
abd52a13 | 58 | DEFINE_MUTEX(w1_mlock); |
1da177e4 LT |
59 | LIST_HEAD(w1_masters); |
60 | ||
1da177e4 LT |
61 | static int w1_master_match(struct device *dev, struct device_driver *drv) |
62 | { | |
63 | return 1; | |
64 | } | |
65 | ||
66 | static int w1_master_probe(struct device *dev) | |
67 | { | |
68 | return -ENODEV; | |
69 | } | |
70 | ||
1da177e4 LT |
71 | static void w1_master_release(struct device *dev) |
72 | { | |
db2d0008 | 73 | struct w1_master *md = dev_to_w1_master(dev); |
3aca692d EP |
74 | |
75 | dev_dbg(dev, "%s: Releasing %s.\n", __func__, md->name); | |
3aca692d EP |
76 | memset(md, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master)); |
77 | kfree(md); | |
1da177e4 LT |
78 | } |
79 | ||
80 | static void w1_slave_release(struct device *dev) | |
81 | { | |
db2d0008 | 82 | struct w1_slave *sl = dev_to_w1_slave(dev); |
3aca692d | 83 | |
9fcbbac5 | 84 | dev_dbg(dev, "%s: Releasing %s [%p]\n", __func__, sl->name, sl); |
3aca692d EP |
85 | |
86 | w1_family_put(sl->family); | |
87 | sl->master->slave_count--; | |
1da177e4 LT |
88 | } |
89 | ||
5b187b3c | 90 | static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 91 | { |
3aca692d | 92 | struct w1_slave *sl = dev_to_w1_slave(dev); |
d2a4ef6a | 93 | |
3aca692d | 94 | return sprintf(buf, "%s\n", sl->name); |
1da177e4 | 95 | } |
5b187b3c | 96 | static DEVICE_ATTR_RO(name); |
1da177e4 | 97 | |
5b187b3c | 98 | static ssize_t id_show(struct device *dev, |
07e00341 | 99 | struct device_attribute *attr, char *buf) |
1da177e4 | 100 | { |
07e00341 DF |
101 | struct w1_slave *sl = dev_to_w1_slave(dev); |
102 | ssize_t count = sizeof(sl->reg_num); | |
d2a4ef6a | 103 | |
07e00341 | 104 | memcpy(buf, (u8 *)&sl->reg_num, count); |
d2a4ef6a | 105 | return count; |
3aca692d | 106 | } |
5b187b3c | 107 | static DEVICE_ATTR_RO(id); |
d2a4ef6a | 108 | |
5b187b3c GKH |
109 | static struct attribute *w1_slave_attrs[] = { |
110 | &dev_attr_name.attr, | |
111 | &dev_attr_id.attr, | |
112 | NULL, | |
113 | }; | |
114 | ATTRIBUTE_GROUPS(w1_slave); | |
7785925d | 115 | |
d2a4ef6a | 116 | /* Default family */ |
f522d239 | 117 | |
36c27a65 GKH |
118 | static ssize_t rw_write(struct file *filp, struct kobject *kobj, |
119 | struct bin_attribute *bin_attr, char *buf, loff_t off, | |
120 | size_t count) | |
f522d239 EP |
121 | { |
122 | struct w1_slave *sl = kobj_to_w1_slave(kobj); | |
123 | ||
abd52a13 | 124 | mutex_lock(&sl->master->mutex); |
f522d239 EP |
125 | if (w1_reset_select_slave(sl)) { |
126 | count = 0; | |
127 | goto out_up; | |
128 | } | |
129 | ||
130 | w1_write_block(sl->master, buf, count); | |
131 | ||
132 | out_up: | |
abd52a13 | 133 | mutex_unlock(&sl->master->mutex); |
f522d239 EP |
134 | return count; |
135 | } | |
136 | ||
36c27a65 GKH |
137 | static ssize_t rw_read(struct file *filp, struct kobject *kobj, |
138 | struct bin_attribute *bin_attr, char *buf, loff_t off, | |
139 | size_t count) | |
f522d239 EP |
140 | { |
141 | struct w1_slave *sl = kobj_to_w1_slave(kobj); | |
142 | ||
abd52a13 | 143 | mutex_lock(&sl->master->mutex); |
f522d239 | 144 | w1_read_block(sl->master, buf, count); |
abd52a13 | 145 | mutex_unlock(&sl->master->mutex); |
f522d239 EP |
146 | return count; |
147 | } | |
148 | ||
36c27a65 GKH |
149 | static BIN_ATTR_RW(rw, PAGE_SIZE); |
150 | ||
151 | static struct bin_attribute *w1_slave_bin_attrs[] = { | |
152 | &bin_attr_rw, | |
153 | NULL, | |
f522d239 EP |
154 | }; |
155 | ||
36c27a65 GKH |
156 | static const struct attribute_group w1_slave_default_group = { |
157 | .bin_attrs = w1_slave_bin_attrs, | |
158 | }; | |
f522d239 | 159 | |
36c27a65 GKH |
160 | static const struct attribute_group *w1_slave_default_groups[] = { |
161 | &w1_slave_default_group, | |
162 | NULL, | |
163 | }; | |
f522d239 | 164 | |
57de2dfc | 165 | static const struct w1_family_ops w1_default_fops = { |
36c27a65 | 166 | .groups = w1_slave_default_groups, |
f522d239 EP |
167 | }; |
168 | ||
169 | static struct w1_family w1_default_family = { | |
170 | .fops = &w1_default_fops, | |
171 | }; | |
d2a4ef6a | 172 | |
7eff2e7a | 173 | static int w1_uevent(struct device *dev, struct kobj_uevent_env *env); |
7785925d | 174 | |
1da177e4 LT |
175 | static struct bus_type w1_bus_type = { |
176 | .name = "w1", | |
177 | .match = w1_master_match, | |
312c004d | 178 | .uevent = w1_uevent, |
1da177e4 LT |
179 | }; |
180 | ||
7f772ed8 EP |
181 | struct device_driver w1_master_driver = { |
182 | .name = "w1_master_driver", | |
1da177e4 LT |
183 | .bus = &w1_bus_type, |
184 | .probe = w1_master_probe, | |
1da177e4 LT |
185 | }; |
186 | ||
7f772ed8 | 187 | struct device w1_master_device = { |
1da177e4 LT |
188 | .parent = NULL, |
189 | .bus = &w1_bus_type, | |
40f91de6 | 190 | .init_name = "w1 bus master", |
7f772ed8 | 191 | .driver = &w1_master_driver, |
1da177e4 LT |
192 | .release = &w1_master_release |
193 | }; | |
194 | ||
2c5bfdac | 195 | static struct device_driver w1_slave_driver = { |
7f772ed8 EP |
196 | .name = "w1_slave_driver", |
197 | .bus = &w1_bus_type, | |
198 | }; | |
199 | ||
2c5bfdac | 200 | #if 0 |
7f772ed8 EP |
201 | struct device w1_slave_device = { |
202 | .parent = NULL, | |
203 | .bus = &w1_bus_type, | |
40f91de6 | 204 | .init_name = "w1 bus slave", |
7f772ed8 | 205 | .driver = &w1_slave_driver, |
3aca692d | 206 | .release = &w1_slave_release |
7f772ed8 | 207 | }; |
2c5bfdac | 208 | #endif /* 0 */ |
7f772ed8 | 209 | |
060b8845 | 210 | static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 211 | { |
db2d0008 | 212 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 213 | ssize_t count; |
7785925d | 214 | |
abd52a13 | 215 | mutex_lock(&md->mutex); |
1da177e4 | 216 | count = sprintf(buf, "%s\n", md->name); |
abd52a13 | 217 | mutex_unlock(&md->mutex); |
1da177e4 LT |
218 | |
219 | return count; | |
220 | } | |
221 | ||
2a9d0c17 EP |
222 | static ssize_t w1_master_attribute_store_search(struct device * dev, |
223 | struct device_attribute *attr, | |
224 | const char * buf, size_t count) | |
225 | { | |
6a158c0d | 226 | long tmp; |
db2d0008 | 227 | struct w1_master *md = dev_to_w1_master(dev); |
bf4228f0 | 228 | int ret; |
2a9d0c17 | 229 | |
bf4228f0 JH |
230 | ret = kstrtol(buf, 0, &tmp); |
231 | if (ret) | |
232 | return ret; | |
6a158c0d | 233 | |
abd52a13 | 234 | mutex_lock(&md->mutex); |
6a158c0d | 235 | md->search_count = tmp; |
abd52a13 | 236 | mutex_unlock(&md->mutex); |
af8c7237 DF |
237 | /* Only wake if it is going to be searching. */ |
238 | if (tmp) | |
239 | wake_up_process(md->thread); | |
2a9d0c17 EP |
240 | |
241 | return count; | |
242 | } | |
243 | ||
244 | static ssize_t w1_master_attribute_show_search(struct device *dev, | |
245 | struct device_attribute *attr, | |
246 | char *buf) | |
247 | { | |
db2d0008 | 248 | struct w1_master *md = dev_to_w1_master(dev); |
2a9d0c17 EP |
249 | ssize_t count; |
250 | ||
abd52a13 | 251 | mutex_lock(&md->mutex); |
2a9d0c17 | 252 | count = sprintf(buf, "%d\n", md->search_count); |
abd52a13 | 253 | mutex_unlock(&md->mutex); |
2a9d0c17 EP |
254 | |
255 | return count; | |
256 | } | |
257 | ||
6a158c0d DF |
258 | static ssize_t w1_master_attribute_store_pullup(struct device *dev, |
259 | struct device_attribute *attr, | |
260 | const char *buf, size_t count) | |
261 | { | |
262 | long tmp; | |
263 | struct w1_master *md = dev_to_w1_master(dev); | |
bf4228f0 | 264 | int ret; |
6a158c0d | 265 | |
bf4228f0 JH |
266 | ret = kstrtol(buf, 0, &tmp); |
267 | if (ret) | |
268 | return ret; | |
6a158c0d DF |
269 | |
270 | mutex_lock(&md->mutex); | |
271 | md->enable_pullup = tmp; | |
272 | mutex_unlock(&md->mutex); | |
6a158c0d DF |
273 | |
274 | return count; | |
275 | } | |
276 | ||
277 | static ssize_t w1_master_attribute_show_pullup(struct device *dev, | |
278 | struct device_attribute *attr, | |
279 | char *buf) | |
280 | { | |
281 | struct w1_master *md = dev_to_w1_master(dev); | |
282 | ssize_t count; | |
283 | ||
284 | mutex_lock(&md->mutex); | |
285 | count = sprintf(buf, "%d\n", md->enable_pullup); | |
286 | mutex_unlock(&md->mutex); | |
287 | ||
288 | return count; | |
289 | } | |
290 | ||
060b8845 | 291 | static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 292 | { |
db2d0008 | 293 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 294 | ssize_t count; |
7785925d | 295 | |
abd52a13 | 296 | mutex_lock(&md->mutex); |
1da177e4 | 297 | count = sprintf(buf, "0x%p\n", md->bus_master); |
abd52a13 | 298 | mutex_unlock(&md->mutex); |
1da177e4 LT |
299 | return count; |
300 | } | |
301 | ||
060b8845 | 302 | static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
303 | { |
304 | ssize_t count; | |
305 | count = sprintf(buf, "%d\n", w1_timeout); | |
306 | return count; | |
307 | } | |
308 | ||
c3098356 DK |
309 | static ssize_t w1_master_attribute_show_timeout_us(struct device *dev, |
310 | struct device_attribute *attr, char *buf) | |
311 | { | |
312 | ssize_t count; | |
313 | count = sprintf(buf, "%d\n", w1_timeout_us); | |
314 | return count; | |
315 | } | |
316 | ||
a1613056 DF |
317 | static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev, |
318 | struct device_attribute *attr, const char *buf, size_t count) | |
319 | { | |
a7155f4e | 320 | int tmp; |
a1613056 DF |
321 | struct w1_master *md = dev_to_w1_master(dev); |
322 | ||
b9c11a23 | 323 | if (kstrtoint(buf, 0, &tmp) || tmp < 1) |
a1613056 DF |
324 | return -EINVAL; |
325 | ||
326 | mutex_lock(&md->mutex); | |
327 | md->max_slave_count = tmp; | |
328 | /* allow each time the max_slave_count is updated */ | |
329 | clear_bit(W1_WARN_MAX_COUNT, &md->flags); | |
330 | mutex_unlock(&md->mutex); | |
331 | ||
332 | return count; | |
333 | } | |
334 | ||
060b8845 | 335 | static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 336 | { |
db2d0008 | 337 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 338 | ssize_t count; |
7785925d | 339 | |
abd52a13 | 340 | mutex_lock(&md->mutex); |
1da177e4 | 341 | count = sprintf(buf, "%d\n", md->max_slave_count); |
abd52a13 | 342 | mutex_unlock(&md->mutex); |
1da177e4 LT |
343 | return count; |
344 | } | |
345 | ||
060b8845 | 346 | static ssize_t w1_master_attribute_show_attempts(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 347 | { |
db2d0008 | 348 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 349 | ssize_t count; |
7785925d | 350 | |
abd52a13 | 351 | mutex_lock(&md->mutex); |
1da177e4 | 352 | count = sprintf(buf, "%lu\n", md->attempts); |
abd52a13 | 353 | mutex_unlock(&md->mutex); |
1da177e4 LT |
354 | return count; |
355 | } | |
356 | ||
060b8845 | 357 | static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 | 358 | { |
db2d0008 | 359 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 360 | ssize_t count; |
7785925d | 361 | |
abd52a13 | 362 | mutex_lock(&md->mutex); |
1da177e4 | 363 | count = sprintf(buf, "%d\n", md->slave_count); |
abd52a13 | 364 | mutex_unlock(&md->mutex); |
1da177e4 LT |
365 | return count; |
366 | } | |
367 | ||
9b467411 DF |
368 | static ssize_t w1_master_attribute_show_slaves(struct device *dev, |
369 | struct device_attribute *attr, char *buf) | |
1da177e4 | 370 | { |
db2d0008 | 371 | struct w1_master *md = dev_to_w1_master(dev); |
1da177e4 | 372 | int c = PAGE_SIZE; |
9fcbbac5 DF |
373 | struct list_head *ent, *n; |
374 | struct w1_slave *sl = NULL; | |
1da177e4 | 375 | |
9fcbbac5 | 376 | mutex_lock(&md->list_mutex); |
1da177e4 | 377 | |
9fcbbac5 DF |
378 | list_for_each_safe(ent, n, &md->slist) { |
379 | sl = list_entry(ent, struct w1_slave, w1_slave_entry); | |
1da177e4 | 380 | |
9fcbbac5 | 381 | c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name); |
1da177e4 | 382 | } |
9fcbbac5 DF |
383 | if (!sl) |
384 | c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n"); | |
1da177e4 | 385 | |
9fcbbac5 | 386 | mutex_unlock(&md->list_mutex); |
1da177e4 LT |
387 | |
388 | return PAGE_SIZE - c; | |
389 | } | |
390 | ||
9b467411 DF |
391 | static ssize_t w1_master_attribute_show_add(struct device *dev, |
392 | struct device_attribute *attr, char *buf) | |
393 | { | |
394 | int c = PAGE_SIZE; | |
395 | c -= snprintf(buf+PAGE_SIZE - c, c, | |
396 | "write device id xx-xxxxxxxxxxxx to add slave\n"); | |
397 | return PAGE_SIZE - c; | |
398 | } | |
399 | ||
400 | static int w1_atoreg_num(struct device *dev, const char *buf, size_t count, | |
401 | struct w1_reg_num *rn) | |
402 | { | |
403 | unsigned int family; | |
404 | unsigned long long id; | |
405 | int i; | |
406 | u64 rn64_le; | |
407 | ||
408 | /* The CRC value isn't read from the user because the sysfs directory | |
409 | * doesn't include it and most messages from the bus search don't | |
410 | * print it either. It would be unreasonable for the user to then | |
411 | * provide it. | |
412 | */ | |
413 | const char *error_msg = "bad slave string format, expecting " | |
414 | "ff-dddddddddddd\n"; | |
415 | ||
416 | if (buf[2] != '-') { | |
417 | dev_err(dev, "%s", error_msg); | |
418 | return -EINVAL; | |
419 | } | |
420 | i = sscanf(buf, "%02x-%012llx", &family, &id); | |
421 | if (i != 2) { | |
422 | dev_err(dev, "%s", error_msg); | |
423 | return -EINVAL; | |
424 | } | |
425 | rn->family = family; | |
426 | rn->id = id; | |
427 | ||
428 | rn64_le = cpu_to_le64(*(u64 *)rn); | |
429 | rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7); | |
430 | ||
431 | #if 0 | |
432 | dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n", | |
433 | rn->family, (unsigned long long)rn->id, rn->crc); | |
434 | #endif | |
435 | ||
436 | return 0; | |
437 | } | |
438 | ||
439 | /* Searches the slaves in the w1_master and returns a pointer or NULL. | |
9fcbbac5 | 440 | * Note: must not hold list_mutex |
9b467411 | 441 | */ |
70b34d2e | 442 | struct w1_slave *w1_slave_search_device(struct w1_master *dev, |
9b467411 DF |
443 | struct w1_reg_num *rn) |
444 | { | |
445 | struct w1_slave *sl; | |
9fcbbac5 | 446 | mutex_lock(&dev->list_mutex); |
9b467411 DF |
447 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) { |
448 | if (sl->reg_num.family == rn->family && | |
449 | sl->reg_num.id == rn->id && | |
450 | sl->reg_num.crc == rn->crc) { | |
9fcbbac5 | 451 | mutex_unlock(&dev->list_mutex); |
9b467411 DF |
452 | return sl; |
453 | } | |
454 | } | |
9fcbbac5 | 455 | mutex_unlock(&dev->list_mutex); |
9b467411 DF |
456 | return NULL; |
457 | } | |
458 | ||
459 | static ssize_t w1_master_attribute_store_add(struct device *dev, | |
460 | struct device_attribute *attr, | |
461 | const char *buf, size_t count) | |
462 | { | |
463 | struct w1_master *md = dev_to_w1_master(dev); | |
464 | struct w1_reg_num rn; | |
465 | struct w1_slave *sl; | |
466 | ssize_t result = count; | |
467 | ||
468 | if (w1_atoreg_num(dev, buf, count, &rn)) | |
469 | return -EINVAL; | |
470 | ||
471 | mutex_lock(&md->mutex); | |
472 | sl = w1_slave_search_device(md, &rn); | |
473 | /* It would be nice to do a targeted search one the one-wire bus | |
474 | * for the new device to see if it is out there or not. But the | |
475 | * current search doesn't support that. | |
476 | */ | |
477 | if (sl) { | |
478 | dev_info(dev, "Device %s already exists\n", sl->name); | |
479 | result = -EINVAL; | |
480 | } else { | |
481 | w1_attach_slave_device(md, &rn); | |
482 | } | |
483 | mutex_unlock(&md->mutex); | |
484 | ||
485 | return result; | |
486 | } | |
487 | ||
488 | static ssize_t w1_master_attribute_show_remove(struct device *dev, | |
489 | struct device_attribute *attr, char *buf) | |
490 | { | |
491 | int c = PAGE_SIZE; | |
492 | c -= snprintf(buf+PAGE_SIZE - c, c, | |
493 | "write device id xx-xxxxxxxxxxxx to remove slave\n"); | |
494 | return PAGE_SIZE - c; | |
495 | } | |
496 | ||
497 | static ssize_t w1_master_attribute_store_remove(struct device *dev, | |
498 | struct device_attribute *attr, | |
499 | const char *buf, size_t count) | |
500 | { | |
501 | struct w1_master *md = dev_to_w1_master(dev); | |
502 | struct w1_reg_num rn; | |
503 | struct w1_slave *sl; | |
504 | ssize_t result = count; | |
505 | ||
506 | if (w1_atoreg_num(dev, buf, count, &rn)) | |
507 | return -EINVAL; | |
508 | ||
509 | mutex_lock(&md->mutex); | |
510 | sl = w1_slave_search_device(md, &rn); | |
511 | if (sl) { | |
9fcbbac5 DF |
512 | result = w1_slave_detach(sl); |
513 | /* refcnt 0 means it was detached in the call */ | |
514 | if (result == 0) | |
515 | result = count; | |
9b467411 DF |
516 | } else { |
517 | dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family, | |
518 | (unsigned long long)rn.id); | |
519 | result = -EINVAL; | |
520 | } | |
521 | mutex_unlock(&md->mutex); | |
522 | ||
523 | return result; | |
524 | } | |
525 | ||
7785925d EP |
526 | #define W1_MASTER_ATTR_RO(_name, _mode) \ |
527 | struct device_attribute w1_master_attribute_##_name = \ | |
528 | __ATTR(w1_master_##_name, _mode, \ | |
529 | w1_master_attribute_show_##_name, NULL) | |
530 | ||
2a9d0c17 EP |
531 | #define W1_MASTER_ATTR_RW(_name, _mode) \ |
532 | struct device_attribute w1_master_attribute_##_name = \ | |
533 | __ATTR(w1_master_##_name, _mode, \ | |
534 | w1_master_attribute_show_##_name, \ | |
535 | w1_master_attribute_store_##_name) | |
536 | ||
7785925d EP |
537 | static W1_MASTER_ATTR_RO(name, S_IRUGO); |
538 | static W1_MASTER_ATTR_RO(slaves, S_IRUGO); | |
539 | static W1_MASTER_ATTR_RO(slave_count, S_IRUGO); | |
a1613056 | 540 | static W1_MASTER_ATTR_RW(max_slave_count, S_IRUGO | S_IWUSR | S_IWGRP); |
7785925d EP |
541 | static W1_MASTER_ATTR_RO(attempts, S_IRUGO); |
542 | static W1_MASTER_ATTR_RO(timeout, S_IRUGO); | |
c3098356 | 543 | static W1_MASTER_ATTR_RO(timeout_us, S_IRUGO); |
7785925d | 544 | static W1_MASTER_ATTR_RO(pointer, S_IRUGO); |
12aa4c64 BS |
545 | static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUSR | S_IWGRP); |
546 | static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUSR | S_IWGRP); | |
547 | static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUSR | S_IWGRP); | |
548 | static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUSR | S_IWGRP); | |
7785925d EP |
549 | |
550 | static struct attribute *w1_master_default_attrs[] = { | |
551 | &w1_master_attribute_name.attr, | |
552 | &w1_master_attribute_slaves.attr, | |
553 | &w1_master_attribute_slave_count.attr, | |
554 | &w1_master_attribute_max_slave_count.attr, | |
555 | &w1_master_attribute_attempts.attr, | |
556 | &w1_master_attribute_timeout.attr, | |
c3098356 | 557 | &w1_master_attribute_timeout_us.attr, |
7785925d | 558 | &w1_master_attribute_pointer.attr, |
2a9d0c17 | 559 | &w1_master_attribute_search.attr, |
6a158c0d | 560 | &w1_master_attribute_pullup.attr, |
9b467411 DF |
561 | &w1_master_attribute_add.attr, |
562 | &w1_master_attribute_remove.attr, | |
7785925d | 563 | NULL |
1da177e4 LT |
564 | }; |
565 | ||
a890d56a | 566 | static const struct attribute_group w1_master_defattr_group = { |
7785925d | 567 | .attrs = w1_master_default_attrs, |
1da177e4 LT |
568 | }; |
569 | ||
7785925d EP |
570 | int w1_create_master_attributes(struct w1_master *master) |
571 | { | |
572 | return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group); | |
573 | } | |
574 | ||
c30c9b15 | 575 | void w1_destroy_master_attributes(struct w1_master *master) |
7785925d EP |
576 | { |
577 | sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group); | |
578 | } | |
579 | ||
7eff2e7a | 580 | static int w1_uevent(struct device *dev, struct kobj_uevent_env *env) |
7f772ed8 EP |
581 | { |
582 | struct w1_master *md = NULL; | |
583 | struct w1_slave *sl = NULL; | |
584 | char *event_owner, *name; | |
526be416 | 585 | int err = 0; |
7f772ed8 EP |
586 | |
587 | if (dev->driver == &w1_master_driver) { | |
588 | md = container_of(dev, struct w1_master, dev); | |
589 | event_owner = "master"; | |
590 | name = md->name; | |
591 | } else if (dev->driver == &w1_slave_driver) { | |
592 | sl = container_of(dev, struct w1_slave, dev); | |
593 | event_owner = "slave"; | |
594 | name = sl->name; | |
595 | } else { | |
312c004d | 596 | dev_dbg(dev, "Unknown event.\n"); |
7f772ed8 EP |
597 | return -EINVAL; |
598 | } | |
599 | ||
c6976a4e | 600 | dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n", |
40f91de6 | 601 | event_owner, name, dev_name(dev)); |
7f772ed8 EP |
602 | |
603 | if (dev->driver != &w1_slave_driver || !sl) | |
526be416 | 604 | goto end; |
7f772ed8 | 605 | |
7eff2e7a | 606 | err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family); |
7f772ed8 | 607 | if (err) |
526be416 | 608 | goto end; |
7f772ed8 | 609 | |
7eff2e7a KS |
610 | err = add_uevent_var(env, "W1_SLAVE_ID=%024LX", |
611 | (unsigned long long)sl->reg_num.id); | |
526be416 DN |
612 | end: |
613 | return err; | |
614 | } | |
7f772ed8 | 615 | |
18d7f891 | 616 | static int w1_family_notify(unsigned long action, struct w1_slave *sl) |
47eba33a | 617 | { |
07f8569f | 618 | const struct w1_family_ops *fops; |
47eba33a GKH |
619 | int err; |
620 | ||
36c27a65 | 621 | fops = sl->family->fops; |
47eba33a | 622 | |
2962aece HFV |
623 | if (!fops) |
624 | return 0; | |
625 | ||
47eba33a GKH |
626 | switch (action) { |
627 | case BUS_NOTIFY_ADD_DEVICE: | |
47eba33a | 628 | /* if the family driver needs to initialize something... */ |
36c27a65 GKH |
629 | if (fops->add_slave) { |
630 | err = fops->add_slave(sl); | |
631 | if (err < 0) { | |
632 | dev_err(&sl->dev, | |
633 | "add_slave() call failed. err=%d\n", | |
634 | err); | |
635 | return err; | |
636 | } | |
637 | } | |
638 | if (fops->groups) { | |
639 | err = sysfs_create_groups(&sl->dev.kobj, fops->groups); | |
640 | if (err) { | |
641 | dev_err(&sl->dev, | |
642 | "sysfs group creation failed. err=%d\n", | |
643 | err); | |
644 | return err; | |
645 | } | |
47eba33a | 646 | } |
2eb79548 JRN |
647 | if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info) { |
648 | struct device *hwmon | |
649 | = hwmon_device_register_with_info(&sl->dev, | |
650 | "w1_slave_temp", sl, | |
651 | fops->chip_info, | |
652 | NULL); | |
653 | if (IS_ERR(hwmon)) { | |
654 | dev_warn(&sl->dev, | |
655 | "could not create hwmon device\n"); | |
656 | } else { | |
657 | sl->hwmon = hwmon; | |
658 | } | |
659 | } | |
47eba33a GKH |
660 | break; |
661 | case BUS_NOTIFY_DEL_DEVICE: | |
2eb79548 JRN |
662 | if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info && |
663 | sl->hwmon) | |
664 | hwmon_device_unregister(sl->hwmon); | |
36c27a65 | 665 | if (fops->remove_slave) |
47eba33a | 666 | sl->family->fops->remove_slave(sl); |
36c27a65 GKH |
667 | if (fops->groups) |
668 | sysfs_remove_groups(&sl->dev.kobj, fops->groups); | |
47eba33a GKH |
669 | break; |
670 | } | |
671 | return 0; | |
672 | } | |
673 | ||
1da177e4 LT |
674 | static int __w1_attach_slave_device(struct w1_slave *sl) |
675 | { | |
676 | int err; | |
677 | ||
678 | sl->dev.parent = &sl->master->dev; | |
7f772ed8 | 679 | sl->dev.driver = &w1_slave_driver; |
1da177e4 LT |
680 | sl->dev.bus = &w1_bus_type; |
681 | sl->dev.release = &w1_slave_release; | |
5b187b3c | 682 | sl->dev.groups = w1_slave_groups; |
fae68031 DM |
683 | sl->dev.of_node = of_find_matching_node(sl->master->dev.of_node, |
684 | sl->family->of_match_table); | |
1da177e4 | 685 | |
40f91de6 | 686 | dev_set_name(&sl->dev, "%02x-%012llx", |
6b729861 EP |
687 | (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); | |
1da177e4 | 693 | |
c6976a4e | 694 | dev_dbg(&sl->dev, "%s: registering %s as %p.\n", __func__, |
40f91de6 | 695 | dev_name(&sl->dev), sl); |
1da177e4 | 696 | |
18d7f891 DF |
697 | /* suppress for w1_family_notify before sending KOBJ_ADD */ |
698 | dev_set_uevent_suppress(&sl->dev, true); | |
699 | ||
1da177e4 LT |
700 | err = device_register(&sl->dev); |
701 | if (err < 0) { | |
702 | dev_err(&sl->dev, | |
6b729861 | 703 | "Device registration [%s] failed. err=%d\n", |
40f91de6 | 704 | dev_name(&sl->dev), err); |
0ec4eb71 | 705 | put_device(&sl->dev); |
1da177e4 LT |
706 | return err; |
707 | } | |
18d7f891 | 708 | w1_family_notify(BUS_NOTIFY_ADD_DEVICE, sl); |
1da177e4 | 709 | |
47eba33a GKH |
710 | dev_set_uevent_suppress(&sl->dev, false); |
711 | kobject_uevent(&sl->dev.kobj, KOBJ_ADD); | |
1da177e4 | 712 | |
9fcbbac5 | 713 | mutex_lock(&sl->master->list_mutex); |
1da177e4 | 714 | list_add_tail(&sl->w1_slave_entry, &sl->master->slist); |
9fcbbac5 | 715 | mutex_unlock(&sl->master->list_mutex); |
1da177e4 LT |
716 | |
717 | return 0; | |
718 | } | |
719 | ||
70b34d2e | 720 | int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) |
1da177e4 LT |
721 | { |
722 | struct w1_slave *sl; | |
723 | struct w1_family *f; | |
724 | int err; | |
725 | struct w1_netlink_msg msg; | |
726 | ||
dd00cc48 | 727 | sl = kzalloc(sizeof(struct w1_slave), GFP_KERNEL); |
1da177e4 LT |
728 | if (!sl) { |
729 | dev_err(&dev->dev, | |
730 | "%s: failed to allocate new slave device.\n", | |
731 | __func__); | |
732 | return -ENOMEM; | |
733 | } | |
734 | ||
1da177e4 LT |
735 | |
736 | sl->owner = THIS_MODULE; | |
737 | sl->master = dev; | |
bb670937 | 738 | set_bit(W1_SLAVE_ACTIVE, &sl->flags); |
1da177e4 | 739 | |
12003375 | 740 | memset(&msg, 0, sizeof(msg)); |
1da177e4 | 741 | memcpy(&sl->reg_num, rn, sizeof(sl->reg_num)); |
9fcbbac5 DF |
742 | atomic_set(&sl->refcnt, 1); |
743 | atomic_inc(&sl->master->refcnt); | |
2c927c0c | 744 | dev->slave_count++; |
f6887531 AW |
745 | dev_info(&dev->dev, "Attaching one wire slave %02x.%012llx crc %02x\n", |
746 | rn->family, (unsigned long long)rn->id, rn->crc); | |
1da177e4 | 747 | |
bc04d76d HFV |
748 | /* slave modules need to be loaded in a context with unlocked mutex */ |
749 | mutex_unlock(&dev->mutex); | |
065c0956 | 750 | request_module("w1-family-0x%02X", rn->family); |
bc04d76d | 751 | mutex_lock(&dev->mutex); |
8d7bda51 | 752 | |
1da177e4 LT |
753 | spin_lock(&w1_flock); |
754 | f = w1_family_registered(rn->family); | |
755 | if (!f) { | |
99c5bfe9 | 756 | f= &w1_default_family; |
1da177e4 LT |
757 | dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n", |
758 | rn->family, rn->family, | |
759 | (unsigned long long)rn->id, rn->crc); | |
1da177e4 LT |
760 | } |
761 | __w1_family_get(f); | |
762 | spin_unlock(&w1_flock); | |
763 | ||
764 | sl->family = f; | |
765 | ||
1da177e4 LT |
766 | err = __w1_attach_slave_device(sl); |
767 | if (err < 0) { | |
768 | dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__, | |
769 | sl->name); | |
2c927c0c | 770 | dev->slave_count--; |
1da177e4 | 771 | w1_family_put(sl->family); |
d2ce4ea1 | 772 | atomic_dec(&sl->master->refcnt); |
1da177e4 LT |
773 | kfree(sl); |
774 | return err; | |
775 | } | |
776 | ||
777 | sl->ttl = dev->slave_ttl; | |
1da177e4 | 778 | |
12003375 | 779 | memcpy(msg.id.id, rn, sizeof(msg.id)); |
1da177e4 LT |
780 | msg.type = W1_SLAVE_ADD; |
781 | w1_netlink_send(dev, &msg); | |
782 | ||
783 | return 0; | |
784 | } | |
785 | ||
9fcbbac5 | 786 | int w1_unref_slave(struct w1_slave *sl) |
1da177e4 | 787 | { |
9fcbbac5 DF |
788 | struct w1_master *dev = sl->master; |
789 | int refcnt; | |
790 | mutex_lock(&dev->list_mutex); | |
791 | refcnt = atomic_sub_return(1, &sl->refcnt); | |
792 | if (refcnt == 0) { | |
793 | struct w1_netlink_msg msg; | |
794 | ||
795 | dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__, | |
796 | sl->name, sl); | |
797 | ||
798 | list_del(&sl->w1_slave_entry); | |
799 | ||
800 | memset(&msg, 0, sizeof(msg)); | |
801 | memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id)); | |
802 | msg.type = W1_SLAVE_REMOVE; | |
803 | w1_netlink_send(sl->master, &msg); | |
804 | ||
18d7f891 | 805 | w1_family_notify(BUS_NOTIFY_DEL_DEVICE, sl); |
9fcbbac5 DF |
806 | device_unregister(&sl->dev); |
807 | #ifdef DEBUG | |
808 | memset(sl, 0, sizeof(*sl)); | |
809 | #endif | |
810 | kfree(sl); | |
811 | } | |
812 | atomic_dec(&dev->refcnt); | |
813 | mutex_unlock(&dev->list_mutex); | |
814 | return refcnt; | |
815 | } | |
1da177e4 | 816 | |
9fcbbac5 DF |
817 | int w1_slave_detach(struct w1_slave *sl) |
818 | { | |
819 | /* Only detach a slave once as it decreases the refcnt each time. */ | |
820 | int destroy_now; | |
821 | mutex_lock(&sl->master->list_mutex); | |
822 | destroy_now = !test_bit(W1_SLAVE_DETACH, &sl->flags); | |
823 | set_bit(W1_SLAVE_DETACH, &sl->flags); | |
824 | mutex_unlock(&sl->master->list_mutex); | |
825 | ||
826 | if (destroy_now) | |
827 | destroy_now = !w1_unref_slave(sl); | |
828 | return destroy_now ? 0 : -EBUSY; | |
1da177e4 LT |
829 | } |
830 | ||
12003375 EP |
831 | struct w1_master *w1_search_master_id(u32 id) |
832 | { | |
833 | struct w1_master *dev; | |
834 | int found = 0; | |
835 | ||
abd52a13 | 836 | mutex_lock(&w1_mlock); |
12003375 EP |
837 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
838 | if (dev->id == id) { | |
839 | found = 1; | |
840 | atomic_inc(&dev->refcnt); | |
841 | break; | |
842 | } | |
843 | } | |
abd52a13 | 844 | mutex_unlock(&w1_mlock); |
12003375 EP |
845 | |
846 | return (found)?dev:NULL; | |
847 | } | |
848 | ||
849 | struct w1_slave *w1_search_slave(struct w1_reg_num *id) | |
850 | { | |
851 | struct w1_master *dev; | |
852 | struct w1_slave *sl = NULL; | |
853 | int found = 0; | |
854 | ||
abd52a13 | 855 | mutex_lock(&w1_mlock); |
12003375 | 856 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
9fcbbac5 | 857 | mutex_lock(&dev->list_mutex); |
12003375 EP |
858 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) { |
859 | if (sl->reg_num.family == id->family && | |
860 | sl->reg_num.id == id->id && | |
861 | sl->reg_num.crc == id->crc) { | |
862 | found = 1; | |
863 | atomic_inc(&dev->refcnt); | |
864 | atomic_inc(&sl->refcnt); | |
865 | break; | |
866 | } | |
867 | } | |
9fcbbac5 | 868 | mutex_unlock(&dev->list_mutex); |
12003375 EP |
869 | |
870 | if (found) | |
871 | break; | |
872 | } | |
abd52a13 | 873 | mutex_unlock(&w1_mlock); |
12003375 EP |
874 | |
875 | return (found)?sl:NULL; | |
876 | } | |
877 | ||
c30c9b15 | 878 | void w1_reconnect_slaves(struct w1_family *f, int attach) |
6adf87bd | 879 | { |
c30c9b15 | 880 | struct w1_slave *sl, *sln; |
6adf87bd EP |
881 | struct w1_master *dev; |
882 | ||
abd52a13 | 883 | mutex_lock(&w1_mlock); |
6adf87bd | 884 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
c30c9b15 DF |
885 | dev_dbg(&dev->dev, "Reconnecting slaves in device %s " |
886 | "for family %02x.\n", dev->name, f->fid); | |
887 | mutex_lock(&dev->mutex); | |
9fcbbac5 | 888 | mutex_lock(&dev->list_mutex); |
c30c9b15 DF |
889 | list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { |
890 | /* If it is a new family, slaves with the default | |
891 | * family driver and are that family will be | |
892 | * connected. If the family is going away, devices | |
893 | * matching that family are reconneced. | |
894 | */ | |
895 | if ((attach && sl->family->fid == W1_FAMILY_DEFAULT | |
896 | && sl->reg_num.family == f->fid) || | |
897 | (!attach && sl->family->fid == f->fid)) { | |
898 | struct w1_reg_num rn; | |
899 | ||
9fcbbac5 | 900 | mutex_unlock(&dev->list_mutex); |
c30c9b15 | 901 | memcpy(&rn, &sl->reg_num, sizeof(rn)); |
9fcbbac5 DF |
902 | /* If it was already in use let the automatic |
903 | * scan pick it up again later. | |
904 | */ | |
905 | if (!w1_slave_detach(sl)) | |
906 | w1_attach_slave_device(dev, &rn); | |
907 | mutex_lock(&dev->list_mutex); | |
c30c9b15 DF |
908 | } |
909 | } | |
910 | dev_dbg(&dev->dev, "Reconnecting slaves in device %s " | |
911 | "has been finished.\n", dev->name); | |
9fcbbac5 | 912 | mutex_unlock(&dev->list_mutex); |
c30c9b15 | 913 | mutex_unlock(&dev->mutex); |
6adf87bd | 914 | } |
abd52a13 | 915 | mutex_unlock(&w1_mlock); |
6adf87bd EP |
916 | } |
917 | ||
48b7de66 CV |
918 | static int w1_addr_crc_is_valid(struct w1_master *dev, u64 rn) |
919 | { | |
920 | u64 rn_le = cpu_to_le64(rn); | |
921 | struct w1_reg_num *tmp = (struct w1_reg_num *)&rn; | |
922 | u8 crc; | |
923 | ||
924 | crc = w1_calc_crc8((u8 *)&rn_le, 7); | |
925 | ||
926 | /* quirk: | |
927 | * DS28E04 (1w eeprom) has strapping pins to change | |
928 | * address, but will not update the crc. So normal rules | |
929 | * for consistent w1 addresses are violated. We test | |
930 | * with the 7 LSBs of the address forced high. | |
931 | * | |
932 | * (char*)&rn_le = { family, addr_lsb, ..., addr_msb, crc }. | |
933 | */ | |
934 | if (crc != tmp->crc && tmp->family == W1_FAMILY_DS28E04) { | |
935 | u64 corr_le = rn_le; | |
936 | ||
937 | ((u8 *)&corr_le)[1] |= 0x7f; | |
938 | crc = w1_calc_crc8((u8 *)&corr_le, 7); | |
939 | ||
940 | dev_info(&dev->dev, "DS28E04 crc workaround on %02x.%012llx.%02x\n", | |
941 | tmp->family, (unsigned long long)tmp->id, tmp->crc); | |
942 | } | |
943 | ||
944 | if (crc != tmp->crc) { | |
945 | dev_dbg(&dev->dev, "w1 addr crc mismatch: %02x.%012llx.%02x != 0x%02x.\n", | |
946 | tmp->family, (unsigned long long)tmp->id, tmp->crc, crc); | |
947 | return 0; | |
948 | } | |
949 | return 1; | |
950 | } | |
951 | ||
963bb101 | 952 | void w1_slave_found(struct w1_master *dev, u64 rn) |
1da177e4 | 953 | { |
1da177e4 | 954 | struct w1_slave *sl; |
1da177e4 | 955 | struct w1_reg_num *tmp; |
1da177e4 | 956 | |
c30c9b15 | 957 | atomic_inc(&dev->refcnt); |
7785925d | 958 | |
1da177e4 LT |
959 | tmp = (struct w1_reg_num *) &rn; |
960 | ||
cd7b28d3 DF |
961 | sl = w1_slave_search_device(dev, tmp); |
962 | if (sl) { | |
bb670937 | 963 | set_bit(W1_SLAVE_ACTIVE, &sl->flags); |
cd7b28d3 | 964 | } else { |
48b7de66 | 965 | if (rn && w1_addr_crc_is_valid(dev, rn)) |
cd7b28d3 | 966 | w1_attach_slave_device(dev, tmp); |
1da177e4 | 967 | } |
7785925d | 968 | |
1da177e4 LT |
969 | atomic_dec(&dev->refcnt); |
970 | } | |
971 | ||
6b729861 | 972 | /** |
b3be177a DF |
973 | * w1_search() - Performs a ROM Search & registers any devices found. |
974 | * @dev: The master device to search | |
975 | * @search_type: W1_SEARCH to search all devices, or W1_ALARM_SEARCH | |
976 | * to return only devices in the alarmed state | |
977 | * @cb: Function to call when a device is found | |
978 | * | |
6b729861 EP |
979 | * The 1-wire search is a simple binary tree search. |
980 | * For each bit of the address, we read two bits and write one bit. | |
981 | * The bit written will put to sleep all devies that don't match that bit. | |
982 | * When the two reads differ, the direction choice is obvious. | |
983 | * When both bits are 0, we must choose a path to take. | |
984 | * When we can scan all 64 bits without having to choose a path, we are done. | |
985 | * | |
986 | * See "Application note 187 1-wire search algorithm" at www.maxim-ic.com | |
987 | * | |
6b729861 | 988 | */ |
12003375 | 989 | void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb) |
1da177e4 | 990 | { |
6b729861 EP |
991 | u64 last_rn, rn, tmp64; |
992 | int i, slave_count = 0; | |
993 | int last_zero, last_device; | |
994 | int search_bit, desc_bit; | |
995 | u8 triplet_ret = 0; | |
1da177e4 | 996 | |
6b729861 | 997 | search_bit = 0; |
3c6955e5 DF |
998 | rn = dev->search_id; |
999 | last_rn = 0; | |
6b729861 EP |
1000 | last_device = 0; |
1001 | last_zero = -1; | |
1da177e4 LT |
1002 | |
1003 | desc_bit = 64; | |
1004 | ||
6b729861 EP |
1005 | while ( !last_device && (slave_count++ < dev->max_slave_count) ) { |
1006 | last_rn = rn; | |
1da177e4 LT |
1007 | rn = 0; |
1008 | ||
1da177e4 LT |
1009 | /* |
1010 | * Reset bus and all 1-wire device state machines | |
1011 | * so they can respond to our requests. | |
1012 | * | |
1013 | * Return 0 - device(s) present, 1 - no devices present. | |
1014 | */ | |
b02f8bed | 1015 | mutex_lock(&dev->bus_mutex); |
1da177e4 | 1016 | if (w1_reset_bus(dev)) { |
b02f8bed | 1017 | mutex_unlock(&dev->bus_mutex); |
2da5bf80 | 1018 | dev_dbg(&dev->dev, "No devices present on the wire.\n"); |
1da177e4 LT |
1019 | break; |
1020 | } | |
1021 | ||
c9cbf558 EP |
1022 | /* Do fast search on single slave bus */ |
1023 | if (dev->max_slave_count == 1) { | |
b02f8bed | 1024 | int rv; |
c9cbf558 | 1025 | w1_write_8(dev, W1_READ_ROM); |
b02f8bed N |
1026 | rv = w1_read_block(dev, (u8 *)&rn, 8); |
1027 | mutex_unlock(&dev->bus_mutex); | |
c9cbf558 | 1028 | |
b02f8bed | 1029 | if (rv == 8 && rn) |
c9cbf558 EP |
1030 | cb(dev, rn); |
1031 | ||
1032 | break; | |
1033 | } | |
1034 | ||
6b729861 | 1035 | /* Start the search */ |
12003375 | 1036 | w1_write_8(dev, search_type); |
1da177e4 | 1037 | for (i = 0; i < 64; ++i) { |
6b729861 EP |
1038 | /* Determine the direction/search bit */ |
1039 | if (i == desc_bit) | |
1040 | search_bit = 1; /* took the 0 path last time, so take the 1 path */ | |
1041 | else if (i > desc_bit) | |
1042 | search_bit = 0; /* take the 0 path on the next branch */ | |
1da177e4 | 1043 | else |
6b729861 | 1044 | search_bit = ((last_rn >> i) & 0x1); |
1da177e4 | 1045 | |
b3be177a | 1046 | /* Read two bits and write one bit */ |
6b729861 EP |
1047 | triplet_ret = w1_triplet(dev, search_bit); |
1048 | ||
1049 | /* quit if no device responded */ | |
1050 | if ( (triplet_ret & 0x03) == 0x03 ) | |
1051 | break; | |
1da177e4 | 1052 | |
6b729861 EP |
1053 | /* If both directions were valid, and we took the 0 path... */ |
1054 | if (triplet_ret == 0) | |
1055 | last_zero = i; | |
1da177e4 | 1056 | |
6b729861 EP |
1057 | /* extract the direction taken & update the device number */ |
1058 | tmp64 = (triplet_ret >> 2); | |
1059 | rn |= (tmp64 << i); | |
0d671b27 | 1060 | |
42105698 | 1061 | if (test_bit(W1_ABORT_SEARCH, &dev->flags)) { |
b02f8bed | 1062 | mutex_unlock(&dev->bus_mutex); |
7dc8f527 | 1063 | dev_dbg(&dev->dev, "Abort w1_search\n"); |
0d671b27 DF |
1064 | return; |
1065 | } | |
6b729861 | 1066 | } |
b02f8bed | 1067 | mutex_unlock(&dev->bus_mutex); |
7785925d | 1068 | |
6b729861 | 1069 | if ( (triplet_ret & 0x03) != 0x03 ) { |
3c6955e5 | 1070 | if ((desc_bit == last_zero) || (last_zero < 0)) { |
6b729861 | 1071 | last_device = 1; |
3c6955e5 DF |
1072 | dev->search_id = 0; |
1073 | } else { | |
1074 | dev->search_id = rn; | |
1075 | } | |
6b729861 | 1076 | desc_bit = last_zero; |
c30c9b15 | 1077 | cb(dev, rn); |
6b729861 | 1078 | } |
a1613056 DF |
1079 | |
1080 | if (!last_device && slave_count == dev->max_slave_count && | |
1081 | !test_bit(W1_WARN_MAX_COUNT, &dev->flags)) { | |
3c6955e5 DF |
1082 | /* Only max_slave_count will be scanned in a search, |
1083 | * but it will start where it left off next search | |
1084 | * until all ids are identified and then it will start | |
1085 | * over. A continued search will report the previous | |
1086 | * last id as the first id (provided it is still on the | |
1087 | * bus). | |
1088 | */ | |
a1613056 | 1089 | dev_info(&dev->dev, "%s: max_slave_count %d reached, " |
3c6955e5 | 1090 | "will continue next search.\n", __func__, |
a1613056 DF |
1091 | dev->max_slave_count); |
1092 | set_bit(W1_WARN_MAX_COUNT, &dev->flags); | |
1093 | } | |
1da177e4 LT |
1094 | } |
1095 | } | |
1096 | ||
963bb101 DF |
1097 | void w1_search_process_cb(struct w1_master *dev, u8 search_type, |
1098 | w1_slave_found_callback cb) | |
12003375 EP |
1099 | { |
1100 | struct w1_slave *sl, *sln; | |
1101 | ||
9fcbbac5 | 1102 | mutex_lock(&dev->list_mutex); |
12003375 | 1103 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) |
bb670937 | 1104 | clear_bit(W1_SLAVE_ACTIVE, &sl->flags); |
9fcbbac5 | 1105 | mutex_unlock(&dev->list_mutex); |
12003375 | 1106 | |
963bb101 | 1107 | w1_search_devices(dev, search_type, cb); |
12003375 | 1108 | |
9fcbbac5 | 1109 | mutex_lock(&dev->list_mutex); |
12003375 | 1110 | list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { |
9fcbbac5 DF |
1111 | if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl) { |
1112 | mutex_unlock(&dev->list_mutex); | |
12003375 | 1113 | w1_slave_detach(sl); |
9fcbbac5 DF |
1114 | mutex_lock(&dev->list_mutex); |
1115 | } | |
bb670937 | 1116 | else if (test_bit(W1_SLAVE_ACTIVE, &sl->flags)) |
12003375 EP |
1117 | sl->ttl = dev->slave_ttl; |
1118 | } | |
9fcbbac5 | 1119 | mutex_unlock(&dev->list_mutex); |
12003375 EP |
1120 | |
1121 | if (dev->search_count > 0) | |
1122 | dev->search_count--; | |
1123 | } | |
1124 | ||
963bb101 DF |
1125 | static void w1_search_process(struct w1_master *dev, u8 search_type) |
1126 | { | |
1127 | w1_search_process_cb(dev, search_type, w1_slave_found); | |
1128 | } | |
1129 | ||
b3be177a DF |
1130 | /** |
1131 | * w1_process_callbacks() - execute each dev->async_list callback entry | |
1132 | * @dev: w1_master device | |
1133 | * | |
a0f10464 AK |
1134 | * The w1 master list_mutex must be held. |
1135 | * | |
b3be177a DF |
1136 | * Return: 1 if there were commands to executed 0 otherwise |
1137 | */ | |
9fcbbac5 DF |
1138 | int w1_process_callbacks(struct w1_master *dev) |
1139 | { | |
1140 | int ret = 0; | |
1141 | struct w1_async_cmd *async_cmd, *async_n; | |
1142 | ||
1143 | /* The list can be added to in another thread, loop until it is empty */ | |
1144 | while (!list_empty(&dev->async_list)) { | |
1145 | list_for_each_entry_safe(async_cmd, async_n, &dev->async_list, | |
1146 | async_entry) { | |
1147 | /* drop the lock, if it is a search it can take a long | |
1148 | * time */ | |
1149 | mutex_unlock(&dev->list_mutex); | |
1150 | async_cmd->cb(dev, async_cmd); | |
1151 | ret = 1; | |
1152 | mutex_lock(&dev->list_mutex); | |
1153 | } | |
1154 | } | |
1155 | return ret; | |
1156 | } | |
1157 | ||
1da177e4 LT |
1158 | int w1_process(void *data) |
1159 | { | |
1160 | struct w1_master *dev = (struct w1_master *) data; | |
3c52e4e6 DF |
1161 | /* As long as w1_timeout is only set by a module parameter the sleep |
1162 | * time can be calculated in jiffies once. | |
1163 | */ | |
c3098356 DK |
1164 | const unsigned long jtime = |
1165 | usecs_to_jiffies(w1_timeout * 1000000 + w1_timeout_us); | |
9fcbbac5 DF |
1166 | /* remainder if it woke up early */ |
1167 | unsigned long jremain = 0; | |
1da177e4 | 1168 | |
9fcbbac5 DF |
1169 | for (;;) { |
1170 | ||
1171 | if (!jremain && dev->search_count) { | |
01e14d6d DF |
1172 | mutex_lock(&dev->mutex); |
1173 | w1_search_process(dev, W1_SEARCH); | |
1174 | mutex_unlock(&dev->mutex); | |
1175 | } | |
1176 | ||
9fcbbac5 DF |
1177 | mutex_lock(&dev->list_mutex); |
1178 | /* Note, w1_process_callback drops the lock while processing, | |
1179 | * but locks it again before returning. | |
1180 | */ | |
1181 | if (!w1_process_callbacks(dev) && jremain) { | |
1182 | /* a wake up is either to stop the thread, process | |
1183 | * callbacks, or search, it isn't process callbacks, so | |
1184 | * schedule a search. | |
1185 | */ | |
1186 | jremain = 1; | |
1187 | } | |
1188 | ||
3c52e4e6 DF |
1189 | __set_current_state(TASK_INTERRUPTIBLE); |
1190 | ||
9fcbbac5 DF |
1191 | /* hold list_mutex until after interruptible to prevent loosing |
1192 | * the wakeup signal when async_cmd is added. | |
1193 | */ | |
1194 | mutex_unlock(&dev->list_mutex); | |
1195 | ||
3c52e4e6 DF |
1196 | if (kthread_should_stop()) |
1197 | break; | |
1198 | ||
1199 | /* Only sleep when the search is active. */ | |
9fcbbac5 DF |
1200 | if (dev->search_count) { |
1201 | if (!jremain) | |
1202 | jremain = jtime; | |
1203 | jremain = schedule_timeout(jremain); | |
1204 | } | |
3c52e4e6 DF |
1205 | else |
1206 | schedule(); | |
1da177e4 LT |
1207 | } |
1208 | ||
1209 | atomic_dec(&dev->refcnt); | |
1da177e4 LT |
1210 | |
1211 | return 0; | |
1212 | } | |
1213 | ||
73a98fce | 1214 | static int __init w1_init(void) |
1da177e4 LT |
1215 | { |
1216 | int retval; | |
1217 | ||
fdc9167a | 1218 | pr_info("Driver for 1-wire Dallas network protocol.\n"); |
1da177e4 | 1219 | |
12003375 EP |
1220 | w1_init_netlink(); |
1221 | ||
1da177e4 LT |
1222 | retval = bus_register(&w1_bus_type); |
1223 | if (retval) { | |
fdc9167a | 1224 | pr_err("Failed to register bus. err=%d.\n", retval); |
1da177e4 LT |
1225 | goto err_out_exit_init; |
1226 | } | |
1227 | ||
7f772ed8 | 1228 | retval = driver_register(&w1_master_driver); |
1da177e4 | 1229 | if (retval) { |
fdc9167a | 1230 | pr_err("Failed to register master driver. err=%d.\n", |
1da177e4 LT |
1231 | retval); |
1232 | goto err_out_bus_unregister; | |
1233 | } | |
1234 | ||
7f772ed8 EP |
1235 | retval = driver_register(&w1_slave_driver); |
1236 | if (retval) { | |
fdc9167a | 1237 | pr_err("Failed to register slave driver. err=%d.\n", |
7f772ed8 EP |
1238 | retval); |
1239 | goto err_out_master_unregister; | |
1240 | } | |
1241 | ||
1da177e4 LT |
1242 | return 0; |
1243 | ||
c30c9b15 DF |
1244 | #if 0 |
1245 | /* For undoing the slave register if there was a step after it. */ | |
7f772ed8 EP |
1246 | err_out_slave_unregister: |
1247 | driver_unregister(&w1_slave_driver); | |
c30c9b15 | 1248 | #endif |
7f772ed8 EP |
1249 | |
1250 | err_out_master_unregister: | |
1251 | driver_unregister(&w1_master_driver); | |
1da177e4 LT |
1252 | |
1253 | err_out_bus_unregister: | |
1254 | bus_unregister(&w1_bus_type); | |
1255 | ||
1256 | err_out_exit_init: | |
1257 | return retval; | |
1258 | } | |
1259 | ||
73a98fce | 1260 | static void __exit w1_fini(void) |
1da177e4 LT |
1261 | { |
1262 | struct w1_master *dev; | |
1da177e4 | 1263 | |
c30c9b15 | 1264 | /* Set netlink removal messages and some cleanup */ |
7785925d | 1265 | list_for_each_entry(dev, &w1_masters, w1_master_entry) |
1da177e4 | 1266 | __w1_remove_master_device(dev); |
1da177e4 | 1267 | |
12003375 EP |
1268 | w1_fini_netlink(); |
1269 | ||
7f772ed8 EP |
1270 | driver_unregister(&w1_slave_driver); |
1271 | driver_unregister(&w1_master_driver); | |
1da177e4 LT |
1272 | bus_unregister(&w1_bus_type); |
1273 | } | |
1274 | ||
1275 | module_init(w1_init); | |
1276 | module_exit(w1_fini); | |
50fa2951 AD |
1277 | |
1278 | MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); | |
1279 | MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol."); | |
1280 | MODULE_LICENSE("GPL"); |