1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> |
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> |
17 | #include <linux/kthread.h> |
18 | #include <linux/freezer.h> |
19 | #include <linux/hwmon.h> |
20 | #include <linux/of.h> |
21 | |
22 | #include <linux/atomic.h> |
23 | |
24 | #include "w1_internal.h" |
25 | #include "w1_netlink.h" |
26 | |
27 | #define W1_FAMILY_DEFAULT 0 |
28 | #define W1_FAMILY_DS28E04 0x1C /* for crc quirk */ |
29 | |
30 | |
31 | static int w1_timeout = 10; |
32 | module_param_named(timeout, w1_timeout, int, 0); |
33 | MODULE_PARM_DESC(timeout, "time in seconds between automatic slave searches" ); |
34 | |
35 | static int w1_timeout_us; |
36 | module_param_named(timeout_us, w1_timeout_us, int, 0); |
37 | MODULE_PARM_DESC(timeout_us, |
38 | "time in microseconds between automatic slave searches" ); |
39 | |
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 | */ |
48 | int w1_max_slave_count = 64; |
49 | module_param_named(max_slave_count, w1_max_slave_count, int, 0); |
50 | MODULE_PARM_DESC(max_slave_count, |
51 | "maximum number of slaves detected in a search" ); |
52 | |
53 | int w1_max_slave_ttl = 10; |
54 | module_param_named(slave_ttl, w1_max_slave_ttl, int, 0); |
55 | MODULE_PARM_DESC(slave_ttl, |
56 | "Number of searches not seeing a slave before it will be removed" ); |
57 | |
58 | DEFINE_MUTEX(w1_mlock); |
59 | LIST_HEAD(w1_masters); |
60 | |
61 | static int w1_master_probe(struct device *dev) |
62 | { |
63 | return -ENODEV; |
64 | } |
65 | |
66 | static void w1_master_release(struct device *dev) |
67 | { |
68 | struct w1_master *md = dev_to_w1_master(dev); |
69 | |
70 | dev_dbg(dev, "%s: Releasing %s.\n" , __func__, md->name); |
71 | memset(md, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master)); |
72 | kfree(objp: md); |
73 | } |
74 | |
75 | static void w1_slave_release(struct device *dev) |
76 | { |
77 | struct w1_slave *sl = dev_to_w1_slave(dev); |
78 | |
79 | dev_dbg(dev, "%s: Releasing %s [%p]\n" , __func__, sl->name, sl); |
80 | |
81 | w1_family_put(f: sl->family); |
82 | sl->master->slave_count--; |
83 | } |
84 | |
85 | static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf) |
86 | { |
87 | struct w1_slave *sl = dev_to_w1_slave(dev); |
88 | |
89 | return sprintf(buf, fmt: "%s\n" , sl->name); |
90 | } |
91 | static DEVICE_ATTR_RO(name); |
92 | |
93 | static ssize_t id_show(struct device *dev, |
94 | struct device_attribute *attr, char *buf) |
95 | { |
96 | struct w1_slave *sl = dev_to_w1_slave(dev); |
97 | ssize_t count = sizeof(sl->reg_num); |
98 | |
99 | memcpy(buf, (u8 *)&sl->reg_num, count); |
100 | return count; |
101 | } |
102 | static DEVICE_ATTR_RO(id); |
103 | |
104 | static struct attribute *w1_slave_attrs[] = { |
105 | &dev_attr_name.attr, |
106 | &dev_attr_id.attr, |
107 | NULL, |
108 | }; |
109 | ATTRIBUTE_GROUPS(w1_slave); |
110 | |
111 | /* Default family */ |
112 | |
113 | static ssize_t rw_write(struct file *filp, struct kobject *kobj, |
114 | struct bin_attribute *bin_attr, char *buf, loff_t off, |
115 | size_t count) |
116 | { |
117 | struct w1_slave *sl = kobj_to_w1_slave(kobj); |
118 | |
119 | mutex_lock(&sl->master->mutex); |
120 | if (w1_reset_select_slave(sl)) { |
121 | count = 0; |
122 | goto out_up; |
123 | } |
124 | |
125 | w1_write_block(sl->master, buf, count); |
126 | |
127 | out_up: |
128 | mutex_unlock(lock: &sl->master->mutex); |
129 | return count; |
130 | } |
131 | |
132 | static ssize_t rw_read(struct file *filp, struct kobject *kobj, |
133 | struct bin_attribute *bin_attr, char *buf, loff_t off, |
134 | size_t count) |
135 | { |
136 | struct w1_slave *sl = kobj_to_w1_slave(kobj); |
137 | |
138 | mutex_lock(&sl->master->mutex); |
139 | w1_read_block(sl->master, buf, count); |
140 | mutex_unlock(lock: &sl->master->mutex); |
141 | return count; |
142 | } |
143 | |
144 | static BIN_ATTR_RW(rw, PAGE_SIZE); |
145 | |
146 | static struct bin_attribute *w1_slave_bin_attrs[] = { |
147 | &bin_attr_rw, |
148 | NULL, |
149 | }; |
150 | |
151 | static const struct attribute_group w1_slave_default_group = { |
152 | .bin_attrs = w1_slave_bin_attrs, |
153 | }; |
154 | |
155 | static const struct attribute_group *w1_slave_default_groups[] = { |
156 | &w1_slave_default_group, |
157 | NULL, |
158 | }; |
159 | |
160 | static const struct w1_family_ops w1_default_fops = { |
161 | .groups = w1_slave_default_groups, |
162 | }; |
163 | |
164 | static struct w1_family w1_default_family = { |
165 | .fops = &w1_default_fops, |
166 | }; |
167 | |
168 | static int w1_uevent(const struct device *dev, struct kobj_uevent_env *env); |
169 | |
170 | static const struct bus_type w1_bus_type = { |
171 | .name = "w1" , |
172 | .uevent = w1_uevent, |
173 | }; |
174 | |
175 | struct device_driver w1_master_driver = { |
176 | .name = "w1_master_driver" , |
177 | .bus = &w1_bus_type, |
178 | .probe = w1_master_probe, |
179 | }; |
180 | |
181 | struct device w1_master_device = { |
182 | .parent = NULL, |
183 | .bus = &w1_bus_type, |
184 | .init_name = "w1 bus master" , |
185 | .driver = &w1_master_driver, |
186 | .release = &w1_master_release |
187 | }; |
188 | |
189 | static struct device_driver w1_slave_driver = { |
190 | .name = "w1_slave_driver" , |
191 | .bus = &w1_bus_type, |
192 | }; |
193 | |
194 | #if 0 |
195 | struct device w1_slave_device = { |
196 | .parent = NULL, |
197 | .bus = &w1_bus_type, |
198 | .init_name = "w1 bus slave" , |
199 | .driver = &w1_slave_driver, |
200 | .release = &w1_slave_release |
201 | }; |
202 | #endif /* 0 */ |
203 | |
204 | static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_attribute *attr, char *buf) |
205 | { |
206 | struct w1_master *md = dev_to_w1_master(dev); |
207 | ssize_t count; |
208 | |
209 | mutex_lock(&md->mutex); |
210 | count = sprintf(buf, fmt: "%s\n" , md->name); |
211 | mutex_unlock(lock: &md->mutex); |
212 | |
213 | return count; |
214 | } |
215 | |
216 | static ssize_t w1_master_attribute_store_search(struct device * dev, |
217 | struct device_attribute *attr, |
218 | const char * buf, size_t count) |
219 | { |
220 | long tmp; |
221 | struct w1_master *md = dev_to_w1_master(dev); |
222 | int ret; |
223 | |
224 | ret = kstrtol(s: buf, base: 0, res: &tmp); |
225 | if (ret) |
226 | return ret; |
227 | |
228 | mutex_lock(&md->mutex); |
229 | md->search_count = tmp; |
230 | mutex_unlock(lock: &md->mutex); |
231 | /* Only wake if it is going to be searching. */ |
232 | if (tmp) |
233 | wake_up_process(tsk: md->thread); |
234 | |
235 | return count; |
236 | } |
237 | |
238 | static ssize_t w1_master_attribute_show_search(struct device *dev, |
239 | struct device_attribute *attr, |
240 | char *buf) |
241 | { |
242 | struct w1_master *md = dev_to_w1_master(dev); |
243 | ssize_t count; |
244 | |
245 | mutex_lock(&md->mutex); |
246 | count = sprintf(buf, fmt: "%d\n" , md->search_count); |
247 | mutex_unlock(lock: &md->mutex); |
248 | |
249 | return count; |
250 | } |
251 | |
252 | static ssize_t w1_master_attribute_store_pullup(struct device *dev, |
253 | struct device_attribute *attr, |
254 | const char *buf, size_t count) |
255 | { |
256 | long tmp; |
257 | struct w1_master *md = dev_to_w1_master(dev); |
258 | int ret; |
259 | |
260 | ret = kstrtol(s: buf, base: 0, res: &tmp); |
261 | if (ret) |
262 | return ret; |
263 | |
264 | mutex_lock(&md->mutex); |
265 | md->enable_pullup = tmp; |
266 | mutex_unlock(lock: &md->mutex); |
267 | |
268 | return count; |
269 | } |
270 | |
271 | static ssize_t w1_master_attribute_show_pullup(struct device *dev, |
272 | struct device_attribute *attr, |
273 | char *buf) |
274 | { |
275 | struct w1_master *md = dev_to_w1_master(dev); |
276 | ssize_t count; |
277 | |
278 | mutex_lock(&md->mutex); |
279 | count = sprintf(buf, fmt: "%d\n" , md->enable_pullup); |
280 | mutex_unlock(lock: &md->mutex); |
281 | |
282 | return count; |
283 | } |
284 | |
285 | static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf) |
286 | { |
287 | struct w1_master *md = dev_to_w1_master(dev); |
288 | ssize_t count; |
289 | |
290 | mutex_lock(&md->mutex); |
291 | count = sprintf(buf, fmt: "0x%p\n" , md->bus_master); |
292 | mutex_unlock(lock: &md->mutex); |
293 | return count; |
294 | } |
295 | |
296 | static ssize_t w1_master_attribute_show_timeout(struct device *dev, struct device_attribute *attr, char *buf) |
297 | { |
298 | return sprintf(buf, fmt: "%d\n" , w1_timeout); |
299 | } |
300 | |
301 | static ssize_t w1_master_attribute_show_timeout_us(struct device *dev, |
302 | struct device_attribute *attr, char *buf) |
303 | { |
304 | return sprintf(buf, fmt: "%d\n" , w1_timeout_us); |
305 | } |
306 | |
307 | static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev, |
308 | struct device_attribute *attr, const char *buf, size_t count) |
309 | { |
310 | int tmp; |
311 | struct w1_master *md = dev_to_w1_master(dev); |
312 | |
313 | if (kstrtoint(s: buf, base: 0, res: &tmp) || tmp < 1) |
314 | return -EINVAL; |
315 | |
316 | mutex_lock(&md->mutex); |
317 | md->max_slave_count = tmp; |
318 | /* allow each time the max_slave_count is updated */ |
319 | clear_bit(nr: W1_WARN_MAX_COUNT, addr: &md->flags); |
320 | mutex_unlock(lock: &md->mutex); |
321 | |
322 | return count; |
323 | } |
324 | |
325 | static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, struct device_attribute *attr, char *buf) |
326 | { |
327 | struct w1_master *md = dev_to_w1_master(dev); |
328 | ssize_t count; |
329 | |
330 | mutex_lock(&md->mutex); |
331 | count = sprintf(buf, fmt: "%d\n" , md->max_slave_count); |
332 | mutex_unlock(lock: &md->mutex); |
333 | return count; |
334 | } |
335 | |
336 | static ssize_t w1_master_attribute_show_attempts(struct device *dev, struct device_attribute *attr, char *buf) |
337 | { |
338 | struct w1_master *md = dev_to_w1_master(dev); |
339 | ssize_t count; |
340 | |
341 | mutex_lock(&md->mutex); |
342 | count = sprintf(buf, fmt: "%lu\n" , md->attempts); |
343 | mutex_unlock(lock: &md->mutex); |
344 | return count; |
345 | } |
346 | |
347 | static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct device_attribute *attr, char *buf) |
348 | { |
349 | struct w1_master *md = dev_to_w1_master(dev); |
350 | ssize_t count; |
351 | |
352 | mutex_lock(&md->mutex); |
353 | count = sprintf(buf, fmt: "%d\n" , md->slave_count); |
354 | mutex_unlock(lock: &md->mutex); |
355 | return count; |
356 | } |
357 | |
358 | static ssize_t w1_master_attribute_show_slaves(struct device *dev, |
359 | struct device_attribute *attr, char *buf) |
360 | { |
361 | struct w1_master *md = dev_to_w1_master(dev); |
362 | int c = PAGE_SIZE; |
363 | struct list_head *ent, *n; |
364 | struct w1_slave *sl = NULL; |
365 | |
366 | mutex_lock(&md->list_mutex); |
367 | |
368 | list_for_each_safe(ent, n, &md->slist) { |
369 | sl = list_entry(ent, struct w1_slave, w1_slave_entry); |
370 | |
371 | c -= snprintf(buf: buf + PAGE_SIZE - c, size: c, fmt: "%s\n" , sl->name); |
372 | } |
373 | if (!sl) |
374 | c -= snprintf(buf: buf + PAGE_SIZE - c, size: c, fmt: "not found.\n" ); |
375 | |
376 | mutex_unlock(lock: &md->list_mutex); |
377 | |
378 | return PAGE_SIZE - c; |
379 | } |
380 | |
381 | static ssize_t w1_master_attribute_show_add(struct device *dev, |
382 | struct device_attribute *attr, char *buf) |
383 | { |
384 | int c = PAGE_SIZE; |
385 | c -= snprintf(buf: buf+PAGE_SIZE - c, size: c, |
386 | fmt: "write device id xx-xxxxxxxxxxxx to add slave\n" ); |
387 | return PAGE_SIZE - c; |
388 | } |
389 | |
390 | static int w1_atoreg_num(struct device *dev, const char *buf, size_t count, |
391 | struct w1_reg_num *rn) |
392 | { |
393 | unsigned int family; |
394 | unsigned long long id; |
395 | int i; |
396 | u64 rn64_le; |
397 | |
398 | /* The CRC value isn't read from the user because the sysfs directory |
399 | * doesn't include it and most messages from the bus search don't |
400 | * print it either. It would be unreasonable for the user to then |
401 | * provide it. |
402 | */ |
403 | const char *error_msg = "bad slave string format, expecting " |
404 | "ff-dddddddddddd\n" ; |
405 | |
406 | if (buf[2] != '-') { |
407 | dev_err(dev, "%s" , error_msg); |
408 | return -EINVAL; |
409 | } |
410 | i = sscanf(buf, "%02x-%012llx" , &family, &id); |
411 | if (i != 2) { |
412 | dev_err(dev, "%s" , error_msg); |
413 | return -EINVAL; |
414 | } |
415 | rn->family = family; |
416 | rn->id = id; |
417 | |
418 | rn64_le = cpu_to_le64(*(u64 *)rn); |
419 | rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7); |
420 | |
421 | #if 0 |
422 | dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n" , |
423 | rn->family, (unsigned long long)rn->id, rn->crc); |
424 | #endif |
425 | |
426 | return 0; |
427 | } |
428 | |
429 | /* Searches the slaves in the w1_master and returns a pointer or NULL. |
430 | * Note: must not hold list_mutex |
431 | */ |
432 | struct w1_slave *w1_slave_search_device(struct w1_master *dev, |
433 | struct w1_reg_num *rn) |
434 | { |
435 | struct w1_slave *sl; |
436 | mutex_lock(&dev->list_mutex); |
437 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) { |
438 | if (sl->reg_num.family == rn->family && |
439 | sl->reg_num.id == rn->id && |
440 | sl->reg_num.crc == rn->crc) { |
441 | mutex_unlock(lock: &dev->list_mutex); |
442 | return sl; |
443 | } |
444 | } |
445 | mutex_unlock(lock: &dev->list_mutex); |
446 | return NULL; |
447 | } |
448 | |
449 | static ssize_t w1_master_attribute_store_add(struct device *dev, |
450 | struct device_attribute *attr, |
451 | const char *buf, size_t count) |
452 | { |
453 | struct w1_master *md = dev_to_w1_master(dev); |
454 | struct w1_reg_num rn; |
455 | struct w1_slave *sl; |
456 | ssize_t result = count; |
457 | |
458 | if (w1_atoreg_num(dev, buf, count, rn: &rn)) |
459 | return -EINVAL; |
460 | |
461 | mutex_lock(&md->mutex); |
462 | sl = w1_slave_search_device(dev: md, rn: &rn); |
463 | /* It would be nice to do a targeted search one the one-wire bus |
464 | * for the new device to see if it is out there or not. But the |
465 | * current search doesn't support that. |
466 | */ |
467 | if (sl) { |
468 | dev_info(dev, "Device %s already exists\n" , sl->name); |
469 | result = -EINVAL; |
470 | } else { |
471 | w1_attach_slave_device(dev: md, rn: &rn); |
472 | } |
473 | mutex_unlock(lock: &md->mutex); |
474 | |
475 | return result; |
476 | } |
477 | |
478 | static ssize_t w1_master_attribute_show_remove(struct device *dev, |
479 | struct device_attribute *attr, char *buf) |
480 | { |
481 | int c = PAGE_SIZE; |
482 | c -= snprintf(buf: buf+PAGE_SIZE - c, size: c, |
483 | fmt: "write device id xx-xxxxxxxxxxxx to remove slave\n" ); |
484 | return PAGE_SIZE - c; |
485 | } |
486 | |
487 | static ssize_t w1_master_attribute_store_remove(struct device *dev, |
488 | struct device_attribute *attr, |
489 | const char *buf, size_t count) |
490 | { |
491 | struct w1_master *md = dev_to_w1_master(dev); |
492 | struct w1_reg_num rn; |
493 | struct w1_slave *sl; |
494 | ssize_t result; |
495 | |
496 | if (w1_atoreg_num(dev, buf, count, rn: &rn)) |
497 | return -EINVAL; |
498 | |
499 | mutex_lock(&md->mutex); |
500 | sl = w1_slave_search_device(dev: md, rn: &rn); |
501 | if (sl) { |
502 | result = w1_slave_detach(sl); |
503 | /* refcnt 0 means it was detached in the call */ |
504 | if (result == 0) |
505 | result = count; |
506 | } else { |
507 | dev_info(dev, "Device %02x-%012llx doesn't exists\n" , rn.family, |
508 | (unsigned long long)rn.id); |
509 | result = -EINVAL; |
510 | } |
511 | mutex_unlock(lock: &md->mutex); |
512 | |
513 | return result; |
514 | } |
515 | |
516 | #define W1_MASTER_ATTR_RO(_name, _mode) \ |
517 | struct device_attribute w1_master_attribute_##_name = \ |
518 | __ATTR(w1_master_##_name, _mode, \ |
519 | w1_master_attribute_show_##_name, NULL) |
520 | |
521 | #define W1_MASTER_ATTR_RW(_name, _mode) \ |
522 | struct device_attribute w1_master_attribute_##_name = \ |
523 | __ATTR(w1_master_##_name, _mode, \ |
524 | w1_master_attribute_show_##_name, \ |
525 | w1_master_attribute_store_##_name) |
526 | |
527 | static W1_MASTER_ATTR_RO(name, S_IRUGO); |
528 | static W1_MASTER_ATTR_RO(slaves, S_IRUGO); |
529 | static W1_MASTER_ATTR_RO(slave_count, S_IRUGO); |
530 | static W1_MASTER_ATTR_RW(max_slave_count, S_IRUGO | S_IWUSR | S_IWGRP); |
531 | static W1_MASTER_ATTR_RO(attempts, S_IRUGO); |
532 | static W1_MASTER_ATTR_RO(timeout, S_IRUGO); |
533 | static W1_MASTER_ATTR_RO(timeout_us, S_IRUGO); |
534 | static W1_MASTER_ATTR_RO(pointer, S_IRUGO); |
535 | static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUSR | S_IWGRP); |
536 | static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUSR | S_IWGRP); |
537 | static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUSR | S_IWGRP); |
538 | static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUSR | S_IWGRP); |
539 | |
540 | static struct attribute *w1_master_default_attrs[] = { |
541 | &w1_master_attribute_name.attr, |
542 | &w1_master_attribute_slaves.attr, |
543 | &w1_master_attribute_slave_count.attr, |
544 | &w1_master_attribute_max_slave_count.attr, |
545 | &w1_master_attribute_attempts.attr, |
546 | &w1_master_attribute_timeout.attr, |
547 | &w1_master_attribute_timeout_us.attr, |
548 | &w1_master_attribute_pointer.attr, |
549 | &w1_master_attribute_search.attr, |
550 | &w1_master_attribute_pullup.attr, |
551 | &w1_master_attribute_add.attr, |
552 | &w1_master_attribute_remove.attr, |
553 | NULL |
554 | }; |
555 | |
556 | static const struct attribute_group w1_master_defattr_group = { |
557 | .attrs = w1_master_default_attrs, |
558 | }; |
559 | |
560 | int w1_create_master_attributes(struct w1_master *master) |
561 | { |
562 | return sysfs_create_group(kobj: &master->dev.kobj, grp: &w1_master_defattr_group); |
563 | } |
564 | |
565 | void w1_destroy_master_attributes(struct w1_master *master) |
566 | { |
567 | sysfs_remove_group(kobj: &master->dev.kobj, grp: &w1_master_defattr_group); |
568 | } |
569 | |
570 | static int w1_uevent(const struct device *dev, struct kobj_uevent_env *env) |
571 | { |
572 | const struct w1_master *md = NULL; |
573 | const struct w1_slave *sl = NULL; |
574 | const char *event_owner, *name; |
575 | int err = 0; |
576 | |
577 | if (dev->driver == &w1_master_driver) { |
578 | md = container_of(dev, struct w1_master, dev); |
579 | event_owner = "master" ; |
580 | name = md->name; |
581 | } else if (dev->driver == &w1_slave_driver) { |
582 | sl = container_of(dev, struct w1_slave, dev); |
583 | event_owner = "slave" ; |
584 | name = sl->name; |
585 | } else { |
586 | dev_dbg(dev, "Unknown event.\n" ); |
587 | return -EINVAL; |
588 | } |
589 | |
590 | dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n" , |
591 | event_owner, name, dev_name(dev)); |
592 | |
593 | if (dev->driver != &w1_slave_driver || !sl) |
594 | goto end; |
595 | |
596 | err = add_uevent_var(env, format: "W1_FID=%02X" , sl->reg_num.family); |
597 | if (err) |
598 | goto end; |
599 | |
600 | err = add_uevent_var(env, format: "W1_SLAVE_ID=%024LX" , |
601 | (unsigned long long)sl->reg_num.id); |
602 | end: |
603 | return err; |
604 | } |
605 | |
606 | static int w1_family_notify(unsigned long action, struct w1_slave *sl) |
607 | { |
608 | const struct w1_family_ops *fops; |
609 | int err; |
610 | |
611 | fops = sl->family->fops; |
612 | |
613 | if (!fops) |
614 | return 0; |
615 | |
616 | switch (action) { |
617 | case BUS_NOTIFY_ADD_DEVICE: |
618 | /* if the family driver needs to initialize something... */ |
619 | if (fops->add_slave) { |
620 | err = fops->add_slave(sl); |
621 | if (err < 0) { |
622 | dev_err(&sl->dev, |
623 | "add_slave() call failed. err=%d\n" , |
624 | err); |
625 | return err; |
626 | } |
627 | } |
628 | if (fops->groups) { |
629 | err = sysfs_create_groups(kobj: &sl->dev.kobj, groups: fops->groups); |
630 | if (err) { |
631 | dev_err(&sl->dev, |
632 | "sysfs group creation failed. err=%d\n" , |
633 | err); |
634 | return err; |
635 | } |
636 | } |
637 | if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info) { |
638 | struct device *hwmon |
639 | = hwmon_device_register_with_info(dev: &sl->dev, |
640 | name: "w1_slave_temp" , drvdata: sl, |
641 | info: fops->chip_info, |
642 | NULL); |
643 | if (IS_ERR(ptr: hwmon)) { |
644 | dev_warn(&sl->dev, |
645 | "could not create hwmon device\n" ); |
646 | } else { |
647 | sl->hwmon = hwmon; |
648 | } |
649 | } |
650 | break; |
651 | case BUS_NOTIFY_DEL_DEVICE: |
652 | if (IS_REACHABLE(CONFIG_HWMON) && fops->chip_info && |
653 | sl->hwmon) |
654 | hwmon_device_unregister(dev: sl->hwmon); |
655 | if (fops->remove_slave) |
656 | sl->family->fops->remove_slave(sl); |
657 | if (fops->groups) |
658 | sysfs_remove_groups(kobj: &sl->dev.kobj, groups: fops->groups); |
659 | break; |
660 | } |
661 | return 0; |
662 | } |
663 | |
664 | static int __w1_attach_slave_device(struct w1_slave *sl) |
665 | { |
666 | int err; |
667 | |
668 | sl->dev.parent = &sl->master->dev; |
669 | sl->dev.driver = &w1_slave_driver; |
670 | sl->dev.bus = &w1_bus_type; |
671 | sl->dev.release = &w1_slave_release; |
672 | sl->dev.groups = w1_slave_groups; |
673 | sl->dev.of_node = of_find_matching_node(from: sl->master->dev.of_node, |
674 | matches: sl->family->of_match_table); |
675 | |
676 | dev_set_name(dev: &sl->dev, name: "%02x-%012llx" , |
677 | (unsigned int) sl->reg_num.family, |
678 | (unsigned long long) sl->reg_num.id); |
679 | snprintf(buf: &sl->name[0], size: sizeof(sl->name), |
680 | fmt: "%02x-%012llx" , |
681 | (unsigned int) sl->reg_num.family, |
682 | (unsigned long long) sl->reg_num.id); |
683 | |
684 | dev_dbg(&sl->dev, "%s: registering %s as %p.\n" , __func__, |
685 | dev_name(&sl->dev), sl); |
686 | |
687 | /* suppress for w1_family_notify before sending KOBJ_ADD */ |
688 | dev_set_uevent_suppress(dev: &sl->dev, val: true); |
689 | |
690 | err = device_register(dev: &sl->dev); |
691 | if (err < 0) { |
692 | dev_err(&sl->dev, |
693 | "Device registration [%s] failed. err=%d\n" , |
694 | dev_name(&sl->dev), err); |
695 | of_node_put(node: sl->dev.of_node); |
696 | put_device(dev: &sl->dev); |
697 | return err; |
698 | } |
699 | w1_family_notify(action: BUS_NOTIFY_ADD_DEVICE, sl); |
700 | |
701 | dev_set_uevent_suppress(dev: &sl->dev, val: false); |
702 | kobject_uevent(kobj: &sl->dev.kobj, action: KOBJ_ADD); |
703 | |
704 | mutex_lock(&sl->master->list_mutex); |
705 | list_add_tail(new: &sl->w1_slave_entry, head: &sl->master->slist); |
706 | mutex_unlock(lock: &sl->master->list_mutex); |
707 | |
708 | return 0; |
709 | } |
710 | |
711 | int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) |
712 | { |
713 | struct w1_slave *sl; |
714 | struct w1_family *f; |
715 | int err; |
716 | struct w1_netlink_msg msg; |
717 | |
718 | sl = kzalloc(size: sizeof(struct w1_slave), GFP_KERNEL); |
719 | if (!sl) { |
720 | dev_err(&dev->dev, |
721 | "%s: failed to allocate new slave device.\n" , |
722 | __func__); |
723 | return -ENOMEM; |
724 | } |
725 | |
726 | |
727 | sl->owner = THIS_MODULE; |
728 | sl->master = dev; |
729 | set_bit(W1_SLAVE_ACTIVE, addr: &sl->flags); |
730 | |
731 | memset(&msg, 0, sizeof(msg)); |
732 | memcpy(&sl->reg_num, rn, sizeof(sl->reg_num)); |
733 | atomic_set(v: &sl->refcnt, i: 1); |
734 | atomic_inc(v: &sl->master->refcnt); |
735 | dev->slave_count++; |
736 | dev_info(&dev->dev, "Attaching one wire slave %02x.%012llx crc %02x\n" , |
737 | rn->family, (unsigned long long)rn->id, rn->crc); |
738 | |
739 | /* slave modules need to be loaded in a context with unlocked mutex */ |
740 | mutex_unlock(lock: &dev->mutex); |
741 | request_module("w1-family-0x%02X" , rn->family); |
742 | mutex_lock(&dev->mutex); |
743 | |
744 | spin_lock(lock: &w1_flock); |
745 | f = w1_family_registered(fid: rn->family); |
746 | if (!f) { |
747 | f= &w1_default_family; |
748 | 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); |
751 | } |
752 | __w1_family_get(f); |
753 | spin_unlock(lock: &w1_flock); |
754 | |
755 | sl->family = f; |
756 | |
757 | err = __w1_attach_slave_device(sl); |
758 | if (err < 0) { |
759 | dev_err(&dev->dev, "%s: Attaching %s failed.\n" , __func__, |
760 | sl->name); |
761 | dev->slave_count--; |
762 | w1_family_put(f: sl->family); |
763 | atomic_dec(v: &sl->master->refcnt); |
764 | kfree(objp: sl); |
765 | return err; |
766 | } |
767 | |
768 | sl->ttl = dev->slave_ttl; |
769 | |
770 | memcpy(msg.id.id, rn, sizeof(msg.id)); |
771 | msg.type = W1_SLAVE_ADD; |
772 | w1_netlink_send(dev, &msg); |
773 | |
774 | return 0; |
775 | } |
776 | |
777 | int w1_unref_slave(struct w1_slave *sl) |
778 | { |
779 | struct w1_master *dev = sl->master; |
780 | int refcnt; |
781 | mutex_lock(&dev->list_mutex); |
782 | refcnt = atomic_sub_return(i: 1, v: &sl->refcnt); |
783 | if (refcnt == 0) { |
784 | struct w1_netlink_msg msg; |
785 | |
786 | dev_dbg(&sl->dev, "%s: detaching %s [%p].\n" , __func__, |
787 | sl->name, sl); |
788 | |
789 | list_del(entry: &sl->w1_slave_entry); |
790 | |
791 | memset(&msg, 0, sizeof(msg)); |
792 | memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id)); |
793 | msg.type = W1_SLAVE_REMOVE; |
794 | w1_netlink_send(sl->master, &msg); |
795 | |
796 | w1_family_notify(action: BUS_NOTIFY_DEL_DEVICE, sl); |
797 | device_unregister(dev: &sl->dev); |
798 | #ifdef DEBUG |
799 | memset(sl, 0, sizeof(*sl)); |
800 | #endif |
801 | kfree(objp: sl); |
802 | } |
803 | atomic_dec(v: &dev->refcnt); |
804 | mutex_unlock(lock: &dev->list_mutex); |
805 | return refcnt; |
806 | } |
807 | |
808 | int w1_slave_detach(struct w1_slave *sl) |
809 | { |
810 | /* Only detach a slave once as it decreases the refcnt each time. */ |
811 | int destroy_now; |
812 | mutex_lock(&sl->master->list_mutex); |
813 | destroy_now = !test_bit(W1_SLAVE_DETACH, &sl->flags); |
814 | set_bit(W1_SLAVE_DETACH, addr: &sl->flags); |
815 | mutex_unlock(lock: &sl->master->list_mutex); |
816 | |
817 | if (destroy_now) |
818 | destroy_now = !w1_unref_slave(sl); |
819 | return destroy_now ? 0 : -EBUSY; |
820 | } |
821 | |
822 | struct w1_master *w1_search_master_id(u32 id) |
823 | { |
824 | struct w1_master *dev = NULL, *iter; |
825 | |
826 | mutex_lock(&w1_mlock); |
827 | list_for_each_entry(iter, &w1_masters, w1_master_entry) { |
828 | if (iter->id == id) { |
829 | dev = iter; |
830 | atomic_inc(v: &iter->refcnt); |
831 | break; |
832 | } |
833 | } |
834 | mutex_unlock(lock: &w1_mlock); |
835 | |
836 | return dev; |
837 | } |
838 | |
839 | struct w1_slave *w1_search_slave(struct w1_reg_num *id) |
840 | { |
841 | struct w1_master *dev; |
842 | struct w1_slave *sl = NULL, *iter; |
843 | |
844 | mutex_lock(&w1_mlock); |
845 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
846 | mutex_lock(&dev->list_mutex); |
847 | list_for_each_entry(iter, &dev->slist, w1_slave_entry) { |
848 | if (iter->reg_num.family == id->family && |
849 | iter->reg_num.id == id->id && |
850 | iter->reg_num.crc == id->crc) { |
851 | sl = iter; |
852 | atomic_inc(v: &dev->refcnt); |
853 | atomic_inc(v: &iter->refcnt); |
854 | break; |
855 | } |
856 | } |
857 | mutex_unlock(lock: &dev->list_mutex); |
858 | |
859 | if (sl) |
860 | break; |
861 | } |
862 | mutex_unlock(lock: &w1_mlock); |
863 | |
864 | return sl; |
865 | } |
866 | |
867 | void w1_reconnect_slaves(struct w1_family *f, int attach) |
868 | { |
869 | struct w1_slave *sl, *sln; |
870 | struct w1_master *dev; |
871 | |
872 | mutex_lock(&w1_mlock); |
873 | list_for_each_entry(dev, &w1_masters, w1_master_entry) { |
874 | dev_dbg(&dev->dev, "Reconnecting slaves in device %s " |
875 | "for family %02x.\n" , dev->name, f->fid); |
876 | mutex_lock(&dev->mutex); |
877 | mutex_lock(&dev->list_mutex); |
878 | list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { |
879 | /* If it is a new family, slaves with the default |
880 | * family driver and are that family will be |
881 | * connected. If the family is going away, devices |
882 | * matching that family are reconneced. |
883 | */ |
884 | if ((attach && sl->family->fid == W1_FAMILY_DEFAULT |
885 | && sl->reg_num.family == f->fid) || |
886 | (!attach && sl->family->fid == f->fid)) { |
887 | struct w1_reg_num rn; |
888 | |
889 | mutex_unlock(lock: &dev->list_mutex); |
890 | memcpy(&rn, &sl->reg_num, sizeof(rn)); |
891 | /* If it was already in use let the automatic |
892 | * scan pick it up again later. |
893 | */ |
894 | if (!w1_slave_detach(sl)) |
895 | w1_attach_slave_device(dev, rn: &rn); |
896 | mutex_lock(&dev->list_mutex); |
897 | } |
898 | } |
899 | dev_dbg(&dev->dev, "Reconnecting slaves in device %s " |
900 | "has been finished.\n" , dev->name); |
901 | mutex_unlock(lock: &dev->list_mutex); |
902 | mutex_unlock(lock: &dev->mutex); |
903 | } |
904 | mutex_unlock(lock: &w1_mlock); |
905 | } |
906 | |
907 | static int w1_addr_crc_is_valid(struct w1_master *dev, u64 rn) |
908 | { |
909 | u64 rn_le = cpu_to_le64(rn); |
910 | struct w1_reg_num *tmp = (struct w1_reg_num *)&rn; |
911 | u8 crc; |
912 | |
913 | crc = w1_calc_crc8((u8 *)&rn_le, 7); |
914 | |
915 | /* quirk: |
916 | * DS28E04 (1w eeprom) has strapping pins to change |
917 | * address, but will not update the crc. So normal rules |
918 | * for consistent w1 addresses are violated. We test |
919 | * with the 7 LSBs of the address forced high. |
920 | * |
921 | * (char*)&rn_le = { family, addr_lsb, ..., addr_msb, crc }. |
922 | */ |
923 | if (crc != tmp->crc && tmp->family == W1_FAMILY_DS28E04) { |
924 | u64 corr_le = rn_le; |
925 | |
926 | ((u8 *)&corr_le)[1] |= 0x7f; |
927 | crc = w1_calc_crc8((u8 *)&corr_le, 7); |
928 | |
929 | dev_info(&dev->dev, "DS28E04 crc workaround on %02x.%012llx.%02x\n" , |
930 | tmp->family, (unsigned long long)tmp->id, tmp->crc); |
931 | } |
932 | |
933 | if (crc != tmp->crc) { |
934 | dev_dbg(&dev->dev, "w1 addr crc mismatch: %02x.%012llx.%02x != 0x%02x.\n" , |
935 | tmp->family, (unsigned long long)tmp->id, tmp->crc, crc); |
936 | return 0; |
937 | } |
938 | return 1; |
939 | } |
940 | |
941 | void w1_slave_found(struct w1_master *dev, u64 rn) |
942 | { |
943 | struct w1_slave *sl; |
944 | struct w1_reg_num *tmp; |
945 | |
946 | atomic_inc(v: &dev->refcnt); |
947 | |
948 | tmp = (struct w1_reg_num *) &rn; |
949 | |
950 | sl = w1_slave_search_device(dev, rn: tmp); |
951 | if (sl) { |
952 | set_bit(W1_SLAVE_ACTIVE, addr: &sl->flags); |
953 | } else { |
954 | if (rn && w1_addr_crc_is_valid(dev, rn)) |
955 | w1_attach_slave_device(dev, rn: tmp); |
956 | } |
957 | |
958 | atomic_dec(v: &dev->refcnt); |
959 | } |
960 | |
961 | /** |
962 | * w1_search() - Performs a ROM Search & registers any devices found. |
963 | * @dev: The master device to search |
964 | * @search_type: W1_SEARCH to search all devices, or W1_ALARM_SEARCH |
965 | * to return only devices in the alarmed state |
966 | * @cb: Function to call when a device is found |
967 | * |
968 | * The 1-wire search is a simple binary tree search. |
969 | * For each bit of the address, we read two bits and write one bit. |
970 | * The bit written will put to sleep all devies that don't match that bit. |
971 | * When the two reads differ, the direction choice is obvious. |
972 | * When both bits are 0, we must choose a path to take. |
973 | * When we can scan all 64 bits without having to choose a path, we are done. |
974 | * |
975 | * See "Application note 187 1-wire search algorithm" at www.maxim-ic.com |
976 | * |
977 | */ |
978 | void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb) |
979 | { |
980 | u64 last_rn, rn, tmp64; |
981 | int i, slave_count = 0; |
982 | int last_zero, last_device; |
983 | int search_bit, desc_bit; |
984 | u8 triplet_ret = 0; |
985 | |
986 | search_bit = 0; |
987 | rn = dev->search_id; |
988 | last_rn = 0; |
989 | last_device = 0; |
990 | last_zero = -1; |
991 | |
992 | desc_bit = 64; |
993 | |
994 | while ( !last_device && (slave_count++ < dev->max_slave_count) ) { |
995 | last_rn = rn; |
996 | rn = 0; |
997 | |
998 | /* |
999 | * Reset bus and all 1-wire device state machines |
1000 | * so they can respond to our requests. |
1001 | * |
1002 | * Return 0 - device(s) present, 1 - no devices present. |
1003 | */ |
1004 | mutex_lock(&dev->bus_mutex); |
1005 | if (w1_reset_bus(dev)) { |
1006 | mutex_unlock(lock: &dev->bus_mutex); |
1007 | dev_dbg(&dev->dev, "No devices present on the wire.\n" ); |
1008 | break; |
1009 | } |
1010 | |
1011 | /* Do fast search on single slave bus */ |
1012 | if (dev->max_slave_count == 1) { |
1013 | int rv; |
1014 | w1_write_8(dev, W1_READ_ROM); |
1015 | rv = w1_read_block(dev, (u8 *)&rn, 8); |
1016 | mutex_unlock(lock: &dev->bus_mutex); |
1017 | |
1018 | if (rv == 8 && rn) |
1019 | cb(dev, rn); |
1020 | |
1021 | break; |
1022 | } |
1023 | |
1024 | /* Start the search */ |
1025 | w1_write_8(dev, search_type); |
1026 | for (i = 0; i < 64; ++i) { |
1027 | /* Determine the direction/search bit */ |
1028 | if (i == desc_bit) |
1029 | search_bit = 1; /* took the 0 path last time, so take the 1 path */ |
1030 | else if (i > desc_bit) |
1031 | search_bit = 0; /* take the 0 path on the next branch */ |
1032 | else |
1033 | search_bit = ((last_rn >> i) & 0x1); |
1034 | |
1035 | /* Read two bits and write one bit */ |
1036 | triplet_ret = w1_triplet(dev, bdir: search_bit); |
1037 | |
1038 | /* quit if no device responded */ |
1039 | if ( (triplet_ret & 0x03) == 0x03 ) |
1040 | break; |
1041 | |
1042 | /* If both directions were valid, and we took the 0 path... */ |
1043 | if (triplet_ret == 0) |
1044 | last_zero = i; |
1045 | |
1046 | /* extract the direction taken & update the device number */ |
1047 | tmp64 = (triplet_ret >> 2); |
1048 | rn |= (tmp64 << i); |
1049 | |
1050 | if (test_bit(W1_ABORT_SEARCH, &dev->flags)) { |
1051 | mutex_unlock(lock: &dev->bus_mutex); |
1052 | dev_dbg(&dev->dev, "Abort w1_search\n" ); |
1053 | return; |
1054 | } |
1055 | } |
1056 | mutex_unlock(lock: &dev->bus_mutex); |
1057 | |
1058 | if ( (triplet_ret & 0x03) != 0x03 ) { |
1059 | if ((desc_bit == last_zero) || (last_zero < 0)) { |
1060 | last_device = 1; |
1061 | dev->search_id = 0; |
1062 | } else { |
1063 | dev->search_id = rn; |
1064 | } |
1065 | desc_bit = last_zero; |
1066 | cb(dev, rn); |
1067 | } |
1068 | |
1069 | if (!last_device && slave_count == dev->max_slave_count && |
1070 | !test_bit(W1_WARN_MAX_COUNT, &dev->flags)) { |
1071 | /* Only max_slave_count will be scanned in a search, |
1072 | * but it will start where it left off next search |
1073 | * until all ids are identified and then it will start |
1074 | * over. A continued search will report the previous |
1075 | * last id as the first id (provided it is still on the |
1076 | * bus). |
1077 | */ |
1078 | dev_info(&dev->dev, "%s: max_slave_count %d reached, " |
1079 | "will continue next search.\n" , __func__, |
1080 | dev->max_slave_count); |
1081 | set_bit(nr: W1_WARN_MAX_COUNT, addr: &dev->flags); |
1082 | } |
1083 | } |
1084 | } |
1085 | |
1086 | void w1_search_process_cb(struct w1_master *dev, u8 search_type, |
1087 | w1_slave_found_callback cb) |
1088 | { |
1089 | struct w1_slave *sl, *sln; |
1090 | |
1091 | mutex_lock(&dev->list_mutex); |
1092 | list_for_each_entry(sl, &dev->slist, w1_slave_entry) |
1093 | clear_bit(W1_SLAVE_ACTIVE, addr: &sl->flags); |
1094 | mutex_unlock(lock: &dev->list_mutex); |
1095 | |
1096 | w1_search_devices(dev, search_type, cb); |
1097 | |
1098 | mutex_lock(&dev->list_mutex); |
1099 | list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { |
1100 | if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl) { |
1101 | mutex_unlock(lock: &dev->list_mutex); |
1102 | w1_slave_detach(sl); |
1103 | mutex_lock(&dev->list_mutex); |
1104 | } |
1105 | else if (test_bit(W1_SLAVE_ACTIVE, &sl->flags)) |
1106 | sl->ttl = dev->slave_ttl; |
1107 | } |
1108 | mutex_unlock(lock: &dev->list_mutex); |
1109 | |
1110 | if (dev->search_count > 0) |
1111 | dev->search_count--; |
1112 | } |
1113 | |
1114 | static void w1_search_process(struct w1_master *dev, u8 search_type) |
1115 | { |
1116 | w1_search_process_cb(dev, search_type, cb: w1_slave_found); |
1117 | } |
1118 | |
1119 | /** |
1120 | * w1_process_callbacks() - execute each dev->async_list callback entry |
1121 | * @dev: w1_master device |
1122 | * |
1123 | * The w1 master list_mutex must be held. |
1124 | * |
1125 | * Return: 1 if there were commands to executed 0 otherwise |
1126 | */ |
1127 | int w1_process_callbacks(struct w1_master *dev) |
1128 | { |
1129 | int ret = 0; |
1130 | struct w1_async_cmd *async_cmd, *async_n; |
1131 | |
1132 | /* The list can be added to in another thread, loop until it is empty */ |
1133 | while (!list_empty(head: &dev->async_list)) { |
1134 | list_for_each_entry_safe(async_cmd, async_n, &dev->async_list, |
1135 | async_entry) { |
1136 | /* drop the lock, if it is a search it can take a long |
1137 | * time */ |
1138 | mutex_unlock(lock: &dev->list_mutex); |
1139 | async_cmd->cb(dev, async_cmd); |
1140 | ret = 1; |
1141 | mutex_lock(&dev->list_mutex); |
1142 | } |
1143 | } |
1144 | return ret; |
1145 | } |
1146 | |
1147 | int w1_process(void *data) |
1148 | { |
1149 | struct w1_master *dev = (struct w1_master *) data; |
1150 | /* As long as w1_timeout is only set by a module parameter the sleep |
1151 | * time can be calculated in jiffies once. |
1152 | */ |
1153 | const unsigned long jtime = |
1154 | usecs_to_jiffies(u: w1_timeout * 1000000 + w1_timeout_us); |
1155 | /* remainder if it woke up early */ |
1156 | unsigned long jremain = 0; |
1157 | |
1158 | atomic_inc(v: &dev->refcnt); |
1159 | |
1160 | for (;;) { |
1161 | |
1162 | if (!jremain && dev->search_count) { |
1163 | mutex_lock(&dev->mutex); |
1164 | w1_search_process(dev, W1_SEARCH); |
1165 | mutex_unlock(lock: &dev->mutex); |
1166 | } |
1167 | |
1168 | mutex_lock(&dev->list_mutex); |
1169 | /* Note, w1_process_callback drops the lock while processing, |
1170 | * but locks it again before returning. |
1171 | */ |
1172 | if (!w1_process_callbacks(dev) && jremain) { |
1173 | /* a wake up is either to stop the thread, process |
1174 | * callbacks, or search, it isn't process callbacks, so |
1175 | * schedule a search. |
1176 | */ |
1177 | jremain = 1; |
1178 | } |
1179 | |
1180 | __set_current_state(TASK_INTERRUPTIBLE); |
1181 | |
1182 | /* hold list_mutex until after interruptible to prevent loosing |
1183 | * the wakeup signal when async_cmd is added. |
1184 | */ |
1185 | mutex_unlock(lock: &dev->list_mutex); |
1186 | |
1187 | if (kthread_should_stop()) { |
1188 | __set_current_state(TASK_RUNNING); |
1189 | break; |
1190 | } |
1191 | |
1192 | /* Only sleep when the search is active. */ |
1193 | if (dev->search_count) { |
1194 | if (!jremain) |
1195 | jremain = jtime; |
1196 | jremain = schedule_timeout(timeout: jremain); |
1197 | } |
1198 | else |
1199 | schedule(); |
1200 | } |
1201 | |
1202 | atomic_dec(v: &dev->refcnt); |
1203 | |
1204 | return 0; |
1205 | } |
1206 | |
1207 | static int __init w1_init(void) |
1208 | { |
1209 | int retval; |
1210 | |
1211 | pr_info("Driver for 1-wire Dallas network protocol.\n" ); |
1212 | |
1213 | w1_init_netlink(); |
1214 | |
1215 | retval = bus_register(bus: &w1_bus_type); |
1216 | if (retval) { |
1217 | pr_err("Failed to register bus. err=%d.\n" , retval); |
1218 | goto err_out_exit_init; |
1219 | } |
1220 | |
1221 | retval = driver_register(drv: &w1_master_driver); |
1222 | if (retval) { |
1223 | pr_err("Failed to register master driver. err=%d.\n" , |
1224 | retval); |
1225 | goto err_out_bus_unregister; |
1226 | } |
1227 | |
1228 | retval = driver_register(drv: &w1_slave_driver); |
1229 | if (retval) { |
1230 | pr_err("Failed to register slave driver. err=%d.\n" , |
1231 | retval); |
1232 | goto err_out_master_unregister; |
1233 | } |
1234 | |
1235 | return 0; |
1236 | |
1237 | #if 0 |
1238 | /* For undoing the slave register if there was a step after it. */ |
1239 | err_out_slave_unregister: |
1240 | driver_unregister(&w1_slave_driver); |
1241 | #endif |
1242 | |
1243 | err_out_master_unregister: |
1244 | driver_unregister(drv: &w1_master_driver); |
1245 | |
1246 | err_out_bus_unregister: |
1247 | bus_unregister(bus: &w1_bus_type); |
1248 | |
1249 | err_out_exit_init: |
1250 | return retval; |
1251 | } |
1252 | |
1253 | static void __exit w1_fini(void) |
1254 | { |
1255 | struct w1_master *dev, *n; |
1256 | |
1257 | /* Set netlink removal messages and some cleanup */ |
1258 | list_for_each_entry_safe(dev, n, &w1_masters, w1_master_entry) |
1259 | __w1_remove_master_device(dev); |
1260 | |
1261 | w1_fini_netlink(); |
1262 | |
1263 | driver_unregister(drv: &w1_slave_driver); |
1264 | driver_unregister(drv: &w1_master_driver); |
1265 | bus_unregister(bus: &w1_bus_type); |
1266 | } |
1267 | |
1268 | module_init(w1_init); |
1269 | module_exit(w1_fini); |
1270 | |
1271 | MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>" ); |
1272 | MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol." ); |
1273 | MODULE_LICENSE("GPL" ); |
1274 | |