Commit | Line | Data |
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989d42e8 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * bus.c - bus driver management | |
4 | * | |
5 | * Copyright (c) 2002-3 Patrick Mochel | |
6 | * Copyright (c) 2002-3 Open Source Development Labs | |
e5dd1278 GKH |
7 | * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de> |
8 | * Copyright (c) 2007 Novell Inc. | |
1da177e4 LT |
9 | */ |
10 | ||
765230b5 | 11 | #include <linux/async.h> |
1da177e4 LT |
12 | #include <linux/device.h> |
13 | #include <linux/module.h> | |
14 | #include <linux/errno.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
1da177e4 LT |
16 | #include <linux/init.h> |
17 | #include <linux/string.h> | |
ca22e56d | 18 | #include <linux/mutex.h> |
63967685 | 19 | #include <linux/sysfs.h> |
1da177e4 LT |
20 | #include "base.h" |
21 | #include "power/power.h" | |
22 | ||
ca22e56d | 23 | /* /sys/devices/system */ |
97ec448a | 24 | static struct kset *system_kset; |
ca22e56d | 25 | |
1da177e4 | 26 | #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) |
1da177e4 LT |
27 | |
28 | /* | |
29 | * sysfs bindings for drivers | |
30 | */ | |
31 | ||
32 | #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) | |
1da177e4 | 33 | |
4f4b3743 DV |
34 | #define DRIVER_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ |
35 | struct driver_attribute driver_attr_##_name = \ | |
36 | __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) | |
1da177e4 | 37 | |
b8c5cec2 KS |
38 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
39 | void *data); | |
40 | ||
5901d014 GKH |
41 | static struct bus_type *bus_get(struct bus_type *bus) |
42 | { | |
c6f7e72a GKH |
43 | if (bus) { |
44 | kset_get(&bus->p->subsys); | |
45 | return bus; | |
46 | } | |
47 | return NULL; | |
5901d014 GKH |
48 | } |
49 | ||
fc1ede58 GKH |
50 | static void bus_put(struct bus_type *bus) |
51 | { | |
c6f7e72a GKH |
52 | if (bus) |
53 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
54 | } |
55 | ||
4a3ad20c GKH |
56 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
57 | char *buf) | |
1da177e4 | 58 | { |
4a3ad20c | 59 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 60 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 61 | ssize_t ret = -EIO; |
1da177e4 LT |
62 | |
63 | if (drv_attr->show) | |
e5dd1278 | 64 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
65 | return ret; |
66 | } | |
67 | ||
4a3ad20c GKH |
68 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
69 | const char *buf, size_t count) | |
1da177e4 | 70 | { |
4a3ad20c | 71 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 72 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 73 | ssize_t ret = -EIO; |
1da177e4 LT |
74 | |
75 | if (drv_attr->store) | |
e5dd1278 | 76 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
77 | return ret; |
78 | } | |
79 | ||
52cf25d0 | 80 | static const struct sysfs_ops driver_sysfs_ops = { |
1da177e4 LT |
81 | .show = drv_attr_show, |
82 | .store = drv_attr_store, | |
83 | }; | |
84 | ||
e5dd1278 | 85 | static void driver_release(struct kobject *kobj) |
1da177e4 | 86 | { |
e5dd1278 GKH |
87 | struct driver_private *drv_priv = to_driver(kobj); |
88 | ||
2b3a302a | 89 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 90 | kfree(drv_priv); |
1da177e4 LT |
91 | } |
92 | ||
a1148fb0 | 93 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
94 | .sysfs_ops = &driver_sysfs_ops, |
95 | .release = driver_release, | |
96 | }; | |
97 | ||
1da177e4 LT |
98 | /* |
99 | * sysfs bindings for buses | |
100 | */ | |
4a3ad20c GKH |
101 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
102 | char *buf) | |
1da177e4 | 103 | { |
4a3ad20c | 104 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 105 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
106 | ssize_t ret = 0; |
107 | ||
108 | if (bus_attr->show) | |
6b6e39a6 | 109 | ret = bus_attr->show(subsys_priv->bus, buf); |
1da177e4 LT |
110 | return ret; |
111 | } | |
112 | ||
4a3ad20c GKH |
113 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
114 | const char *buf, size_t count) | |
1da177e4 | 115 | { |
4a3ad20c | 116 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 117 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
118 | ssize_t ret = 0; |
119 | ||
120 | if (bus_attr->store) | |
6b6e39a6 | 121 | ret = bus_attr->store(subsys_priv->bus, buf, count); |
1da177e4 LT |
122 | return ret; |
123 | } | |
124 | ||
52cf25d0 | 125 | static const struct sysfs_ops bus_sysfs_ops = { |
1da177e4 LT |
126 | .show = bus_attr_show, |
127 | .store = bus_attr_store, | |
128 | }; | |
129 | ||
4a3ad20c | 130 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
131 | { |
132 | int error; | |
5901d014 | 133 | if (bus_get(bus)) { |
c6f7e72a | 134 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 135 | bus_put(bus); |
1da177e4 LT |
136 | } else |
137 | error = -EINVAL; | |
138 | return error; | |
139 | } | |
4a3ad20c | 140 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 141 | |
4a3ad20c | 142 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 143 | { |
5901d014 | 144 | if (bus_get(bus)) { |
c6f7e72a | 145 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 146 | bus_put(bus); |
1da177e4 LT |
147 | } |
148 | } | |
4a3ad20c | 149 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 150 | |
174be70b BVA |
151 | static void bus_release(struct kobject *kobj) |
152 | { | |
371fd7a2 | 153 | struct subsys_private *priv = to_subsys_private(kobj); |
174be70b BVA |
154 | struct bus_type *bus = priv->bus; |
155 | ||
156 | kfree(priv); | |
157 | bus->p = NULL; | |
158 | } | |
159 | ||
80f03e34 | 160 | static struct kobj_type bus_ktype = { |
1da177e4 | 161 | .sysfs_ops = &bus_sysfs_ops, |
174be70b | 162 | .release = bus_release, |
80f03e34 KS |
163 | }; |
164 | ||
165 | static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) | |
166 | { | |
167 | struct kobj_type *ktype = get_ktype(kobj); | |
168 | ||
169 | if (ktype == &bus_ktype) | |
170 | return 1; | |
171 | return 0; | |
172 | } | |
1da177e4 | 173 | |
9cd43611 | 174 | static const struct kset_uevent_ops bus_uevent_ops = { |
80f03e34 | 175 | .filter = bus_uevent_filter, |
1da177e4 LT |
176 | }; |
177 | ||
59a54833 | 178 | static struct kset *bus_kset; |
1da177e4 | 179 | |
2b08c8d0 | 180 | /* Manually detach a device from its associated driver. */ |
2581c9cc GKH |
181 | static ssize_t unbind_store(struct device_driver *drv, const char *buf, |
182 | size_t count) | |
151ef38f | 183 | { |
5901d014 | 184 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
185 | struct device *dev; |
186 | int err = -ENODEV; | |
187 | ||
1f9ffc04 | 188 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 189 | if (dev && dev->driver == drv) { |
ed88747c | 190 | device_driver_detach(dev); |
151ef38f GKH |
191 | err = count; |
192 | } | |
2b08c8d0 | 193 | put_device(dev); |
fc1ede58 | 194 | bus_put(bus); |
2b08c8d0 | 195 | return err; |
151ef38f | 196 | } |
4f4b3743 | 197 | static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, S_IWUSR, NULL, unbind_store); |
151ef38f | 198 | |
afdce75f GKH |
199 | /* |
200 | * Manually attach a device to a driver. | |
201 | * Note: the driver must want to bind to the device, | |
202 | * it is not possible to override the driver's id table. | |
203 | */ | |
2581c9cc GKH |
204 | static ssize_t bind_store(struct device_driver *drv, const char *buf, |
205 | size_t count) | |
afdce75f | 206 | { |
5901d014 | 207 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
208 | struct device *dev; |
209 | int err = -ENODEV; | |
210 | ||
1f9ffc04 | 211 | dev = bus_find_device_by_name(bus, NULL, buf); |
49b420a1 | 212 | if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { |
ed88747c | 213 | err = device_driver_attach(drv, dev); |
37225401 | 214 | |
4a3ad20c GKH |
215 | if (err > 0) { |
216 | /* success */ | |
37225401 | 217 | err = count; |
4a3ad20c GKH |
218 | } else if (err == 0) { |
219 | /* driver didn't accept device */ | |
37225401 | 220 | err = -ENODEV; |
4a3ad20c | 221 | } |
afdce75f | 222 | } |
2b08c8d0 | 223 | put_device(dev); |
fc1ede58 | 224 | bus_put(bus); |
2b08c8d0 | 225 | return err; |
afdce75f | 226 | } |
4f4b3743 | 227 | static DRIVER_ATTR_IGNORE_LOCKDEP(bind, S_IWUSR, NULL, bind_store); |
afdce75f | 228 | |
2e7189b6 | 229 | static ssize_t drivers_autoprobe_show(struct bus_type *bus, char *buf) |
b8c5cec2 | 230 | { |
c6f7e72a | 231 | return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
232 | } |
233 | ||
2e7189b6 | 234 | static ssize_t drivers_autoprobe_store(struct bus_type *bus, |
b8c5cec2 KS |
235 | const char *buf, size_t count) |
236 | { | |
237 | if (buf[0] == '0') | |
c6f7e72a | 238 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 239 | else |
c6f7e72a | 240 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
241 | return count; |
242 | } | |
243 | ||
2e7189b6 | 244 | static ssize_t drivers_probe_store(struct bus_type *bus, |
b8c5cec2 KS |
245 | const char *buf, size_t count) |
246 | { | |
247 | struct device *dev; | |
0372ffb3 | 248 | int err = -EINVAL; |
b8c5cec2 | 249 | |
1f9ffc04 | 250 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
251 | if (!dev) |
252 | return -ENODEV; | |
0372ffb3 AW |
253 | if (bus_rescan_devices_helper(dev, NULL) == 0) |
254 | err = count; | |
255 | put_device(dev); | |
256 | return err; | |
b8c5cec2 | 257 | } |
151ef38f | 258 | |
4a3ad20c | 259 | static struct device *next_device(struct klist_iter *i) |
465c7a3a | 260 | { |
4a3ad20c | 261 | struct klist_node *n = klist_next(i); |
ae1b4171 GKH |
262 | struct device *dev = NULL; |
263 | struct device_private *dev_prv; | |
264 | ||
265 | if (n) { | |
266 | dev_prv = to_device_private_bus(n); | |
267 | dev = dev_prv->device; | |
268 | } | |
269 | return dev; | |
465c7a3a | 270 | } |
271 | ||
1da177e4 | 272 | /** |
4a3ad20c GKH |
273 | * bus_for_each_dev - device iterator. |
274 | * @bus: bus type. | |
275 | * @start: device to start iterating from. | |
276 | * @data: data for the callback. | |
277 | * @fn: function to be called for each device. | |
1da177e4 | 278 | * |
4a3ad20c GKH |
279 | * Iterate over @bus's list of devices, and call @fn for each, |
280 | * passing it @data. If @start is not NULL, we use that device to | |
281 | * begin iterating from. | |
1da177e4 | 282 | * |
4a3ad20c GKH |
283 | * We check the return of @fn each time. If it returns anything |
284 | * other than 0, we break out and return that value. | |
1da177e4 | 285 | * |
4a3ad20c GKH |
286 | * NOTE: The device that returns a non-zero value is not retained |
287 | * in any way, nor is its refcount incremented. If the caller needs | |
0fa1b0a1 | 288 | * to retain this data, it should do so, and increment the reference |
4a3ad20c | 289 | * count in the supplied callback. |
1da177e4 | 290 | */ |
4a3ad20c GKH |
291 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
292 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 293 | { |
465c7a3a | 294 | struct klist_iter i; |
4a3ad20c | 295 | struct device *dev; |
465c7a3a | 296 | int error = 0; |
1da177e4 | 297 | |
4fa3e78b | 298 | if (!bus || !bus->p) |
465c7a3a | 299 | return -EINVAL; |
300 | ||
7cd9c9bb GKH |
301 | klist_iter_init_node(&bus->p->klist_devices, &i, |
302 | (start ? &start->p->knode_bus : NULL)); | |
93ead7c9 | 303 | while (!error && (dev = next_device(&i))) |
7cd9c9bb GKH |
304 | error = fn(dev, data); |
305 | klist_iter_exit(&i); | |
465c7a3a | 306 | return error; |
1da177e4 | 307 | } |
4a3ad20c | 308 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 309 | |
0edb5860 CH |
310 | /** |
311 | * bus_find_device - device iterator for locating a particular device. | |
312 | * @bus: bus type | |
313 | * @start: Device to begin with | |
314 | * @data: Data to pass to match function | |
315 | * @match: Callback function to check device | |
316 | * | |
317 | * This is similar to the bus_for_each_dev() function above, but it | |
318 | * returns a reference to a device that is 'found' for later use, as | |
319 | * determined by the @match callback. | |
320 | * | |
321 | * The callback should return 0 if the device doesn't match and non-zero | |
322 | * if it does. If the callback returns non-zero, this function will | |
323 | * return to the caller and not iterate over any more devices. | |
324 | */ | |
4a3ad20c GKH |
325 | struct device *bus_find_device(struct bus_type *bus, |
326 | struct device *start, void *data, | |
327 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
328 | { |
329 | struct klist_iter i; | |
330 | struct device *dev; | |
331 | ||
4fa3e78b | 332 | if (!bus || !bus->p) |
0edb5860 CH |
333 | return NULL; |
334 | ||
7cd9c9bb GKH |
335 | klist_iter_init_node(&bus->p->klist_devices, &i, |
336 | (start ? &start->p->knode_bus : NULL)); | |
0edb5860 CH |
337 | while ((dev = next_device(&i))) |
338 | if (match(dev, data) && get_device(dev)) | |
339 | break; | |
340 | klist_iter_exit(&i); | |
341 | return dev; | |
342 | } | |
4a3ad20c | 343 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 344 | |
1f9ffc04 GKH |
345 | static int match_name(struct device *dev, void *data) |
346 | { | |
347 | const char *name = data; | |
348 | ||
1e0b2cf9 | 349 | return sysfs_streq(name, dev_name(dev)); |
1f9ffc04 GKH |
350 | } |
351 | ||
352 | /** | |
353 | * bus_find_device_by_name - device iterator for locating a particular device of a specific name | |
354 | * @bus: bus type | |
355 | * @start: Device to begin with | |
356 | * @name: name of the device to match | |
357 | * | |
358 | * This is similar to the bus_find_device() function above, but it handles | |
359 | * searching by a name automatically, no need to write another strcmp matching | |
360 | * function. | |
361 | */ | |
362 | struct device *bus_find_device_by_name(struct bus_type *bus, | |
363 | struct device *start, const char *name) | |
364 | { | |
365 | return bus_find_device(bus, start, (void *)name, match_name); | |
366 | } | |
367 | EXPORT_SYMBOL_GPL(bus_find_device_by_name); | |
368 | ||
ca22e56d KS |
369 | /** |
370 | * subsys_find_device_by_id - find a device with a specific enumeration number | |
371 | * @subsys: subsystem | |
372 | * @id: index 'id' in struct device | |
373 | * @hint: device to check first | |
374 | * | |
375 | * Check the hint's next object and if it is a match return it directly, | |
376 | * otherwise, fall back to a full list search. Either way a reference for | |
377 | * the returned object is taken. | |
378 | */ | |
379 | struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, | |
380 | struct device *hint) | |
381 | { | |
382 | struct klist_iter i; | |
383 | struct device *dev; | |
384 | ||
385 | if (!subsys) | |
386 | return NULL; | |
387 | ||
388 | if (hint) { | |
7cd9c9bb | 389 | klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); |
ca22e56d KS |
390 | dev = next_device(&i); |
391 | if (dev && dev->id == id && get_device(dev)) { | |
392 | klist_iter_exit(&i); | |
393 | return dev; | |
394 | } | |
395 | klist_iter_exit(&i); | |
396 | } | |
397 | ||
398 | klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); | |
399 | while ((dev = next_device(&i))) { | |
400 | if (dev->id == id && get_device(dev)) { | |
401 | klist_iter_exit(&i); | |
402 | return dev; | |
403 | } | |
404 | } | |
405 | klist_iter_exit(&i); | |
406 | return NULL; | |
407 | } | |
408 | EXPORT_SYMBOL_GPL(subsys_find_device_by_id); | |
409 | ||
4a3ad20c | 410 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 411 | { |
4a3ad20c | 412 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
413 | struct driver_private *drv_priv; |
414 | ||
415 | if (n) { | |
416 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
417 | return drv_priv->driver; | |
418 | } | |
419 | return NULL; | |
38fdac3c | 420 | } |
421 | ||
1da177e4 | 422 | /** |
4a3ad20c GKH |
423 | * bus_for_each_drv - driver iterator |
424 | * @bus: bus we're dealing with. | |
425 | * @start: driver to start iterating on. | |
426 | * @data: data to pass to the callback. | |
427 | * @fn: function to call for each driver. | |
1da177e4 | 428 | * |
4a3ad20c GKH |
429 | * This is nearly identical to the device iterator above. |
430 | * We iterate over each driver that belongs to @bus, and call | |
431 | * @fn for each. If @fn returns anything but 0, we break out | |
432 | * and return it. If @start is not NULL, we use it as the head | |
433 | * of the list. | |
1da177e4 | 434 | * |
4a3ad20c GKH |
435 | * NOTE: we don't return the driver that returns a non-zero |
436 | * value, nor do we leave the reference count incremented for that | |
437 | * driver. If the caller needs to know that info, it must set it | |
438 | * in the callback. It must also be sure to increment the refcount | |
439 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 440 | */ |
4a3ad20c GKH |
441 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
442 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 443 | { |
38fdac3c | 444 | struct klist_iter i; |
4a3ad20c | 445 | struct device_driver *drv; |
38fdac3c | 446 | int error = 0; |
1da177e4 | 447 | |
38fdac3c | 448 | if (!bus) |
449 | return -EINVAL; | |
450 | ||
7cd9c9bb GKH |
451 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
452 | start ? &start->p->knode_bus : NULL); | |
453 | while ((drv = next_driver(&i)) && !error) | |
454 | error = fn(drv, data); | |
455 | klist_iter_exit(&i); | |
38fdac3c | 456 | return error; |
1da177e4 | 457 | } |
4a3ad20c | 458 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 459 | |
1da177e4 | 460 | /** |
4a3ad20c GKH |
461 | * bus_add_device - add device to bus |
462 | * @dev: device being added | |
1da177e4 | 463 | * |
2023c610 AS |
464 | * - Add device's bus attributes. |
465 | * - Create links to device's bus. | |
4a3ad20c | 466 | * - Add the device to its bus's list of devices. |
1da177e4 | 467 | */ |
4a3ad20c | 468 | int bus_add_device(struct device *dev) |
1da177e4 | 469 | { |
4a3ad20c | 470 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
471 | int error = 0; |
472 | ||
473 | if (bus) { | |
1e0b2cf9 | 474 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
fa6fdb33 GKH |
475 | error = device_add_groups(dev, bus->dev_groups); |
476 | if (error) | |
b46c7337 | 477 | goto out_put; |
c6f7e72a | 478 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 479 | &dev->kobj, dev_name(dev)); |
f86db396 | 480 | if (error) |
1c34203a | 481 | goto out_groups; |
f86db396 | 482 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 483 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 484 | if (error) |
513e7337 | 485 | goto out_subsys; |
2023c610 | 486 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 487 | } |
513e7337 CH |
488 | return 0; |
489 | ||
513e7337 | 490 | out_subsys: |
1e0b2cf9 | 491 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
fa6fdb33 GKH |
492 | out_groups: |
493 | device_remove_groups(dev, bus->dev_groups); | |
513e7337 | 494 | out_put: |
fc1ede58 | 495 | bus_put(dev->bus); |
1da177e4 LT |
496 | return error; |
497 | } | |
498 | ||
53877d06 | 499 | /** |
2023c610 AS |
500 | * bus_probe_device - probe drivers for a new device |
501 | * @dev: device to probe | |
53877d06 | 502 | * |
2023c610 | 503 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 504 | */ |
2023c610 | 505 | void bus_probe_device(struct device *dev) |
53877d06 | 506 | { |
f86db396 | 507 | struct bus_type *bus = dev->bus; |
ca22e56d | 508 | struct subsys_interface *sif; |
53877d06 | 509 | |
ca22e56d KS |
510 | if (!bus) |
511 | return; | |
512 | ||
765230b5 DT |
513 | if (bus->p->drivers_autoprobe) |
514 | device_initial_probe(dev); | |
ca22e56d KS |
515 | |
516 | mutex_lock(&bus->p->mutex); | |
517 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
518 | if (sif->add_dev) | |
519 | sif->add_dev(dev, sif); | |
520 | mutex_unlock(&bus->p->mutex); | |
53877d06 KS |
521 | } |
522 | ||
1da177e4 | 523 | /** |
4a3ad20c GKH |
524 | * bus_remove_device - remove device from bus |
525 | * @dev: device to be removed | |
1da177e4 | 526 | * |
ca22e56d KS |
527 | * - Remove device from all interfaces. |
528 | * - Remove symlink from bus' directory. | |
4a3ad20c GKH |
529 | * - Delete device from bus's list. |
530 | * - Detach from its driver. | |
531 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 532 | */ |
4a3ad20c | 533 | void bus_remove_device(struct device *dev) |
1da177e4 | 534 | { |
ca22e56d KS |
535 | struct bus_type *bus = dev->bus; |
536 | struct subsys_interface *sif; | |
537 | ||
538 | if (!bus) | |
539 | return; | |
540 | ||
541 | mutex_lock(&bus->p->mutex); | |
542 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
543 | if (sif->remove_dev) | |
544 | sif->remove_dev(dev, sif); | |
545 | mutex_unlock(&bus->p->mutex); | |
546 | ||
547 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
548 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, | |
549 | dev_name(dev)); | |
fa6fdb33 | 550 | device_remove_groups(dev, dev->bus->dev_groups); |
ca22e56d KS |
551 | if (klist_node_attached(&dev->p->knode_bus)) |
552 | klist_del(&dev->p->knode_bus); | |
553 | ||
554 | pr_debug("bus: '%s': remove device %s\n", | |
555 | dev->bus->name, dev_name(dev)); | |
556 | device_release_driver(dev); | |
557 | bus_put(dev->bus); | |
1da177e4 LT |
558 | } |
559 | ||
f86db396 | 560 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 561 | { |
f86db396 AM |
562 | int ret; |
563 | ||
564 | ret = driver_create_file(drv, &driver_attr_unbind); | |
565 | if (ret == 0) { | |
566 | ret = driver_create_file(drv, &driver_attr_bind); | |
567 | if (ret) | |
568 | driver_remove_file(drv, &driver_attr_unbind); | |
569 | } | |
570 | return ret; | |
874c6241 GKH |
571 | } |
572 | ||
573 | static void remove_bind_files(struct device_driver *drv) | |
574 | { | |
575 | driver_remove_file(drv, &driver_attr_bind); | |
576 | driver_remove_file(drv, &driver_attr_unbind); | |
577 | } | |
b8c5cec2 | 578 | |
2e7189b6 GKH |
579 | static BUS_ATTR_WO(drivers_probe); |
580 | static BUS_ATTR_RW(drivers_autoprobe); | |
8380770c | 581 | |
b8c5cec2 KS |
582 | static int add_probe_files(struct bus_type *bus) |
583 | { | |
584 | int retval; | |
585 | ||
8380770c | 586 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
587 | if (retval) |
588 | goto out; | |
589 | ||
8380770c | 590 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 591 | if (retval) |
8380770c | 592 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
593 | out: |
594 | return retval; | |
595 | } | |
596 | ||
597 | static void remove_probe_files(struct bus_type *bus) | |
598 | { | |
8380770c KS |
599 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
600 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 601 | } |
1da177e4 | 602 | |
2581c9cc GKH |
603 | static ssize_t uevent_store(struct device_driver *drv, const char *buf, |
604 | size_t count) | |
7ac1cf4a | 605 | { |
df44b479 PR |
606 | int rc; |
607 | ||
608 | rc = kobject_synth_uevent(&drv->p->kobj, buf, count); | |
609 | return rc ? rc : count; | |
7ac1cf4a | 610 | } |
2581c9cc | 611 | static DRIVER_ATTR_WO(uevent); |
7ac1cf4a | 612 | |
1da177e4 | 613 | /** |
4a3ad20c GKH |
614 | * bus_add_driver - Add a driver to the bus. |
615 | * @drv: driver. | |
1da177e4 | 616 | */ |
f86db396 | 617 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 618 | { |
e5dd1278 GKH |
619 | struct bus_type *bus; |
620 | struct driver_private *priv; | |
1da177e4 LT |
621 | int error = 0; |
622 | ||
e5dd1278 | 623 | bus = bus_get(drv->bus); |
d9fd4d3b | 624 | if (!bus) |
4f6e1945 | 625 | return -EINVAL; |
d9fd4d3b | 626 | |
7dc72b28 | 627 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
628 | |
629 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
630 | if (!priv) { |
631 | error = -ENOMEM; | |
632 | goto out_put_bus; | |
633 | } | |
e5dd1278 GKH |
634 | klist_init(&priv->klist_devices, NULL, NULL); |
635 | priv->driver = drv; | |
636 | drv->p = priv; | |
c8e90d82 GKH |
637 | priv->kobj.kset = bus->p->drivers_kset; |
638 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
639 | "%s", drv->name); | |
dc0afa83 | 640 | if (error) |
07634464 | 641 | goto out_unregister; |
d9fd4d3b | 642 | |
190888ac | 643 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
c6f7e72a | 644 | if (drv->bus->p->drivers_autoprobe) { |
ef0ff683 AD |
645 | error = driver_attach(drv); |
646 | if (error) | |
647 | goto out_unregister; | |
b8c5cec2 | 648 | } |
d9fd4d3b JG |
649 | module_add_driver(drv->owner, drv); |
650 | ||
7ac1cf4a KS |
651 | error = driver_create_file(drv, &driver_attr_uevent); |
652 | if (error) { | |
653 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 654 | __func__, drv->name); |
7ac1cf4a | 655 | } |
e18945b1 | 656 | error = driver_add_groups(drv, bus->drv_groups); |
d9fd4d3b JG |
657 | if (error) { |
658 | /* How the hell do we get out of this pickle? Give up */ | |
ed0617b5 GKH |
659 | printk(KERN_ERR "%s: driver_create_groups(%s) failed\n", |
660 | __func__, drv->name); | |
e18945b1 | 661 | } |
1a6f2a75 DT |
662 | |
663 | if (!drv->suppress_bind_attrs) { | |
664 | error = add_bind_files(drv); | |
665 | if (error) { | |
666 | /* Ditto */ | |
667 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
668 | __func__, drv->name); | |
669 | } | |
1da177e4 | 670 | } |
d9fd4d3b | 671 | |
5c8563d7 | 672 | return 0; |
1a6f2a75 | 673 | |
f86db396 | 674 | out_unregister: |
99b28f1b | 675 | kobject_put(&priv->kobj); |
0f9b011d | 676 | /* drv->p is freed in driver_release() */ |
5c8563d7 | 677 | drv->p = NULL; |
f86db396 | 678 | out_put_bus: |
fc1ede58 | 679 | bus_put(bus); |
f86db396 | 680 | return error; |
1da177e4 LT |
681 | } |
682 | ||
1da177e4 | 683 | /** |
4a3ad20c GKH |
684 | * bus_remove_driver - delete driver from bus's knowledge. |
685 | * @drv: driver. | |
1da177e4 | 686 | * |
4a3ad20c GKH |
687 | * Detach the driver from the devices it controls, and remove |
688 | * it from its bus's list of drivers. Finally, we drop the reference | |
689 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 690 | */ |
4a3ad20c | 691 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 692 | { |
d9fd4d3b JG |
693 | if (!drv->bus) |
694 | return; | |
695 | ||
1a6f2a75 DT |
696 | if (!drv->suppress_bind_attrs) |
697 | remove_bind_files(drv); | |
ed0617b5 | 698 | driver_remove_groups(drv, drv->bus->drv_groups); |
7ac1cf4a | 699 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 700 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 701 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
702 | driver_detach(drv); |
703 | module_remove_driver(drv); | |
c10997f6 | 704 | kobject_put(&drv->p->kobj); |
fc1ede58 | 705 | bus_put(drv->bus); |
1da177e4 LT |
706 | } |
707 | ||
1da177e4 | 708 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 709 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 710 | void *data) |
1da177e4 | 711 | { |
f86db396 AM |
712 | int ret = 0; |
713 | ||
bf74ad5b | 714 | if (!dev->driver) { |
8c97a46a | 715 | if (dev->parent && dev->bus->need_parent_lock) |
8e9394ce | 716 | device_lock(dev->parent); |
f86db396 | 717 | ret = device_attach(dev); |
8c97a46a | 718 | if (dev->parent && dev->bus->need_parent_lock) |
8e9394ce | 719 | device_unlock(dev->parent); |
bf74ad5b | 720 | } |
f86db396 | 721 | return ret < 0 ? ret : 0; |
1da177e4 LT |
722 | } |
723 | ||
1da177e4 | 724 | /** |
23d3d602 GKH |
725 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
726 | * @bus: the bus to scan. | |
1da177e4 | 727 | * |
23d3d602 GKH |
728 | * This function will look for devices on the bus with no driver |
729 | * attached and rescan it against existing drivers to see if it matches | |
730 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 731 | */ |
4a3ad20c | 732 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 733 | { |
f86db396 | 734 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 735 | } |
4a3ad20c | 736 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 737 | |
e935d5da ME |
738 | /** |
739 | * device_reprobe - remove driver for a device and probe for a new driver | |
740 | * @dev: the device to reprobe | |
741 | * | |
742 | * This function detaches the attached driver (if any) for the given | |
743 | * device and restarts the driver probing process. It is intended | |
744 | * to use if probing criteria changed during a devices lifetime and | |
745 | * driver attachment should change accordingly. | |
746 | */ | |
f86db396 | 747 | int device_reprobe(struct device *dev) |
e935d5da | 748 | { |
ed88747c AD |
749 | if (dev->driver) |
750 | device_driver_detach(dev); | |
f86db396 | 751 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
752 | } |
753 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 754 | |
1da177e4 | 755 | /** |
4a3ad20c GKH |
756 | * find_bus - locate bus by name. |
757 | * @name: name of bus. | |
1da177e4 | 758 | * |
4a3ad20c GKH |
759 | * Call kset_find_obj() to iterate over list of buses to |
760 | * find a bus by name. Return bus if found. | |
1da177e4 | 761 | * |
4a3ad20c | 762 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 763 | */ |
7e4ef085 | 764 | #if 0 |
4a3ad20c | 765 | struct bus_type *find_bus(char *name) |
1da177e4 | 766 | { |
4a3ad20c | 767 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
768 | return k ? to_bus(k) : NULL; |
769 | } | |
7e4ef085 | 770 | #endif /* 0 */ |
1da177e4 | 771 | |
12478ba0 GKH |
772 | static int bus_add_groups(struct bus_type *bus, |
773 | const struct attribute_group **groups) | |
774 | { | |
3e9b2bae | 775 | return sysfs_create_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
776 | } |
777 | ||
778 | static void bus_remove_groups(struct bus_type *bus, | |
779 | const struct attribute_group **groups) | |
780 | { | |
3e9b2bae | 781 | sysfs_remove_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
782 | } |
783 | ||
34bb61f9 JB |
784 | static void klist_devices_get(struct klist_node *n) |
785 | { | |
ae1b4171 GKH |
786 | struct device_private *dev_prv = to_device_private_bus(n); |
787 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
788 | |
789 | get_device(dev); | |
790 | } | |
791 | ||
792 | static void klist_devices_put(struct klist_node *n) | |
793 | { | |
ae1b4171 GKH |
794 | struct device_private *dev_prv = to_device_private_bus(n); |
795 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
796 | |
797 | put_device(dev); | |
798 | } | |
799 | ||
7ac1cf4a KS |
800 | static ssize_t bus_uevent_store(struct bus_type *bus, |
801 | const char *buf, size_t count) | |
802 | { | |
df44b479 PR |
803 | int rc; |
804 | ||
805 | rc = kobject_synth_uevent(&bus->p->subsys.kobj, buf, count); | |
806 | return rc ? rc : count; | |
7ac1cf4a | 807 | } |
a4723041 GKH |
808 | /* |
809 | * "open code" the old BUS_ATTR() macro here. We want to use BUS_ATTR_WO() | |
810 | * here, but can not use it as earlier in the file we have | |
811 | * DEVICE_ATTR_WO(uevent), which would cause a clash with the with the store | |
812 | * function name. | |
813 | */ | |
814 | static struct bus_attribute bus_attr_uevent = __ATTR(uevent, S_IWUSR, NULL, | |
815 | bus_uevent_store); | |
7ac1cf4a | 816 | |
1da177e4 | 817 | /** |
be871b7e | 818 | * bus_register - register a driver-core subsystem |
78d79559 | 819 | * @bus: bus to register |
1da177e4 | 820 | * |
78d79559 | 821 | * Once we have that, we register the bus with the kobject |
4a3ad20c | 822 | * infrastructure, then register the children subsystems it has: |
ca22e56d | 823 | * the devices and drivers that belong to the subsystem. |
1da177e4 | 824 | */ |
be871b7e | 825 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
826 | { |
827 | int retval; | |
6b6e39a6 | 828 | struct subsys_private *priv; |
be871b7e | 829 | struct lock_class_key *key = &bus->lock_key; |
c6f7e72a | 830 | |
6b6e39a6 | 831 | priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL); |
c6f7e72a GKH |
832 | if (!priv) |
833 | return -ENOMEM; | |
834 | ||
835 | priv->bus = bus; | |
836 | bus->p = priv; | |
1da177e4 | 837 | |
c6f7e72a | 838 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 839 | |
c6f7e72a | 840 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
841 | if (retval) |
842 | goto out; | |
843 | ||
c6f7e72a GKH |
844 | priv->subsys.kobj.kset = bus_kset; |
845 | priv->subsys.kobj.ktype = &bus_ktype; | |
846 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 847 | |
c6f7e72a | 848 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
849 | if (retval) |
850 | goto out; | |
851 | ||
7ac1cf4a KS |
852 | retval = bus_create_file(bus, &bus_attr_uevent); |
853 | if (retval) | |
854 | goto bus_uevent_fail; | |
855 | ||
c6f7e72a GKH |
856 | priv->devices_kset = kset_create_and_add("devices", NULL, |
857 | &priv->subsys.kobj); | |
858 | if (!priv->devices_kset) { | |
3d899596 | 859 | retval = -ENOMEM; |
1da177e4 | 860 | goto bus_devices_fail; |
3d899596 | 861 | } |
1da177e4 | 862 | |
c6f7e72a GKH |
863 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
864 | &priv->subsys.kobj); | |
865 | if (!priv->drivers_kset) { | |
6dcec251 | 866 | retval = -ENOMEM; |
1da177e4 | 867 | goto bus_drivers_fail; |
6dcec251 | 868 | } |
465c7a3a | 869 | |
ca22e56d KS |
870 | INIT_LIST_HEAD(&priv->interfaces); |
871 | __mutex_init(&priv->mutex, "subsys mutex", key); | |
c6f7e72a GKH |
872 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
873 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 874 | |
b8c5cec2 KS |
875 | retval = add_probe_files(bus); |
876 | if (retval) | |
877 | goto bus_probe_files_fail; | |
878 | ||
12478ba0 GKH |
879 | retval = bus_add_groups(bus, bus->bus_groups); |
880 | if (retval) | |
881 | goto bus_groups_fail; | |
1da177e4 | 882 | |
7dc72b28 | 883 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
884 | return 0; |
885 | ||
12478ba0 | 886 | bus_groups_fail: |
b8c5cec2 KS |
887 | remove_probe_files(bus); |
888 | bus_probe_files_fail: | |
c6f7e72a | 889 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 890 | bus_drivers_fail: |
c6f7e72a | 891 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 892 | bus_devices_fail: |
7ac1cf4a KS |
893 | bus_remove_file(bus, &bus_attr_uevent); |
894 | bus_uevent_fail: | |
c6f7e72a | 895 | kset_unregister(&bus->p->subsys); |
1da177e4 | 896 | out: |
600c20f3 | 897 | kfree(bus->p); |
f48f3feb | 898 | bus->p = NULL; |
1da177e4 LT |
899 | return retval; |
900 | } | |
be871b7e | 901 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 902 | |
1da177e4 | 903 | /** |
4a3ad20c GKH |
904 | * bus_unregister - remove a bus from the system |
905 | * @bus: bus. | |
1da177e4 | 906 | * |
4a3ad20c GKH |
907 | * Unregister the child subsystems and the bus itself. |
908 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 909 | */ |
4a3ad20c | 910 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 911 | { |
7dc72b28 | 912 | pr_debug("bus: '%s': unregistering\n", bus->name); |
ca22e56d KS |
913 | if (bus->dev_root) |
914 | device_unregister(bus->dev_root); | |
12478ba0 | 915 | bus_remove_groups(bus, bus->bus_groups); |
b8c5cec2 | 916 | remove_probe_files(bus); |
c6f7e72a GKH |
917 | kset_unregister(bus->p->drivers_kset); |
918 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 919 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a | 920 | kset_unregister(&bus->p->subsys); |
1da177e4 | 921 | } |
4a3ad20c | 922 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 923 | |
116af378 BH |
924 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
925 | { | |
c6f7e72a | 926 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
927 | } |
928 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
929 | ||
930 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
931 | { | |
c6f7e72a | 932 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
933 | } |
934 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
935 | ||
0fed80f7 GKH |
936 | struct kset *bus_get_kset(struct bus_type *bus) |
937 | { | |
c6f7e72a | 938 | return &bus->p->subsys; |
0fed80f7 GKH |
939 | } |
940 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
941 | ||
b249072e GKH |
942 | struct klist *bus_get_device_klist(struct bus_type *bus) |
943 | { | |
c6f7e72a | 944 | return &bus->p->klist_devices; |
b249072e GKH |
945 | } |
946 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
947 | ||
99178b03 | 948 | /* |
dca25ebd | 949 | * Yes, this forcibly breaks the klist abstraction temporarily. It |
99178b03 GKH |
950 | * just wants to sort the klist, not change reference counts and |
951 | * take/drop locks rapidly in the process. It does all this while | |
952 | * holding the lock for the list, so objects can't otherwise be | |
953 | * added/removed while we're swizzling. | |
954 | */ | |
955 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
956 | int (*compare)(const struct device *a, | |
957 | const struct device *b)) | |
958 | { | |
99178b03 | 959 | struct klist_node *n; |
ae1b4171 | 960 | struct device_private *dev_prv; |
99178b03 GKH |
961 | struct device *b; |
962 | ||
4c62785e | 963 | list_for_each_entry(n, list, n_node) { |
ae1b4171 GKH |
964 | dev_prv = to_device_private_bus(n); |
965 | b = dev_prv->device; | |
99178b03 | 966 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
967 | list_move_tail(&a->p->knode_bus.n_node, |
968 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
969 | return; |
970 | } | |
971 | } | |
ae1b4171 | 972 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
973 | } |
974 | ||
975 | void bus_sort_breadthfirst(struct bus_type *bus, | |
976 | int (*compare)(const struct device *a, | |
977 | const struct device *b)) | |
978 | { | |
979 | LIST_HEAD(sorted_devices); | |
4c62785e | 980 | struct klist_node *n, *tmp; |
ae1b4171 | 981 | struct device_private *dev_prv; |
99178b03 GKH |
982 | struct device *dev; |
983 | struct klist *device_klist; | |
984 | ||
985 | device_klist = bus_get_device_klist(bus); | |
986 | ||
987 | spin_lock(&device_klist->k_lock); | |
4c62785e | 988 | list_for_each_entry_safe(n, tmp, &device_klist->k_list, n_node) { |
ae1b4171 GKH |
989 | dev_prv = to_device_private_bus(n); |
990 | dev = dev_prv->device; | |
99178b03 GKH |
991 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
992 | } | |
993 | list_splice(&sorted_devices, &device_klist->k_list); | |
994 | spin_unlock(&device_klist->k_lock); | |
995 | } | |
996 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
997 | ||
ca22e56d KS |
998 | /** |
999 | * subsys_dev_iter_init - initialize subsys device iterator | |
1000 | * @iter: subsys iterator to initialize | |
1001 | * @subsys: the subsys we wanna iterate over | |
1002 | * @start: the device to start iterating from, if any | |
1003 | * @type: device_type of the devices to iterate over, NULL for all | |
1004 | * | |
1005 | * Initialize subsys iterator @iter such that it iterates over devices | |
1006 | * of @subsys. If @start is set, the list iteration will start there, | |
1007 | * otherwise if it is NULL, the iteration starts at the beginning of | |
1008 | * the list. | |
1009 | */ | |
7cd9c9bb GKH |
1010 | void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys, |
1011 | struct device *start, const struct device_type *type) | |
ca22e56d KS |
1012 | { |
1013 | struct klist_node *start_knode = NULL; | |
1014 | ||
1015 | if (start) | |
1016 | start_knode = &start->p->knode_bus; | |
7cd9c9bb GKH |
1017 | klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode); |
1018 | iter->type = type; | |
ca22e56d KS |
1019 | } |
1020 | EXPORT_SYMBOL_GPL(subsys_dev_iter_init); | |
1021 | ||
1022 | /** | |
1023 | * subsys_dev_iter_next - iterate to the next device | |
1024 | * @iter: subsys iterator to proceed | |
1025 | * | |
1026 | * Proceed @iter to the next device and return it. Returns NULL if | |
1027 | * iteration is complete. | |
1028 | * | |
1029 | * The returned device is referenced and won't be released till | |
1030 | * iterator is proceed to the next device or exited. The caller is | |
1031 | * free to do whatever it wants to do with the device including | |
1032 | * calling back into subsys code. | |
1033 | */ | |
1034 | struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter) | |
1035 | { | |
1036 | struct klist_node *knode; | |
1037 | struct device *dev; | |
1038 | ||
1039 | for (;;) { | |
1040 | knode = klist_next(&iter->ki); | |
1041 | if (!knode) | |
1042 | return NULL; | |
371fd7a2 | 1043 | dev = to_device_private_bus(knode)->device; |
ca22e56d KS |
1044 | if (!iter->type || iter->type == dev->type) |
1045 | return dev; | |
1046 | } | |
1047 | } | |
1048 | EXPORT_SYMBOL_GPL(subsys_dev_iter_next); | |
1049 | ||
1050 | /** | |
1051 | * subsys_dev_iter_exit - finish iteration | |
1052 | * @iter: subsys iterator to finish | |
1053 | * | |
1054 | * Finish an iteration. Always call this function after iteration is | |
1055 | * complete whether the iteration ran till the end or not. | |
1056 | */ | |
1057 | void subsys_dev_iter_exit(struct subsys_dev_iter *iter) | |
1058 | { | |
1059 | klist_iter_exit(&iter->ki); | |
1060 | } | |
1061 | EXPORT_SYMBOL_GPL(subsys_dev_iter_exit); | |
1062 | ||
1063 | int subsys_interface_register(struct subsys_interface *sif) | |
1064 | { | |
1065 | struct bus_type *subsys; | |
1066 | struct subsys_dev_iter iter; | |
1067 | struct device *dev; | |
1068 | ||
1069 | if (!sif || !sif->subsys) | |
1070 | return -ENODEV; | |
1071 | ||
1072 | subsys = bus_get(sif->subsys); | |
1073 | if (!subsys) | |
1074 | return -EINVAL; | |
1075 | ||
1076 | mutex_lock(&subsys->p->mutex); | |
1077 | list_add_tail(&sif->node, &subsys->p->interfaces); | |
1078 | if (sif->add_dev) { | |
1079 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1080 | while ((dev = subsys_dev_iter_next(&iter))) | |
1081 | sif->add_dev(dev, sif); | |
1082 | subsys_dev_iter_exit(&iter); | |
1083 | } | |
1084 | mutex_unlock(&subsys->p->mutex); | |
1085 | ||
1086 | return 0; | |
1087 | } | |
1088 | EXPORT_SYMBOL_GPL(subsys_interface_register); | |
1089 | ||
1090 | void subsys_interface_unregister(struct subsys_interface *sif) | |
1091 | { | |
2b31594a | 1092 | struct bus_type *subsys; |
ca22e56d KS |
1093 | struct subsys_dev_iter iter; |
1094 | struct device *dev; | |
1095 | ||
2b31594a | 1096 | if (!sif || !sif->subsys) |
ca22e56d KS |
1097 | return; |
1098 | ||
2b31594a JC |
1099 | subsys = sif->subsys; |
1100 | ||
ca22e56d KS |
1101 | mutex_lock(&subsys->p->mutex); |
1102 | list_del_init(&sif->node); | |
1103 | if (sif->remove_dev) { | |
1104 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1105 | while ((dev = subsys_dev_iter_next(&iter))) | |
1106 | sif->remove_dev(dev, sif); | |
1107 | subsys_dev_iter_exit(&iter); | |
1108 | } | |
1109 | mutex_unlock(&subsys->p->mutex); | |
1110 | ||
1111 | bus_put(subsys); | |
1112 | } | |
1113 | EXPORT_SYMBOL_GPL(subsys_interface_unregister); | |
1114 | ||
1115 | static void system_root_device_release(struct device *dev) | |
1116 | { | |
1117 | kfree(dev); | |
1118 | } | |
d73ce004 TH |
1119 | |
1120 | static int subsys_register(struct bus_type *subsys, | |
1121 | const struct attribute_group **groups, | |
1122 | struct kobject *parent_of_root) | |
ca22e56d KS |
1123 | { |
1124 | struct device *dev; | |
1125 | int err; | |
1126 | ||
1127 | err = bus_register(subsys); | |
1128 | if (err < 0) | |
1129 | return err; | |
1130 | ||
1131 | dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
1132 | if (!dev) { | |
1133 | err = -ENOMEM; | |
1134 | goto err_dev; | |
1135 | } | |
1136 | ||
1137 | err = dev_set_name(dev, "%s", subsys->name); | |
1138 | if (err < 0) | |
1139 | goto err_name; | |
1140 | ||
d73ce004 | 1141 | dev->kobj.parent = parent_of_root; |
ca22e56d KS |
1142 | dev->groups = groups; |
1143 | dev->release = system_root_device_release; | |
1144 | ||
1145 | err = device_register(dev); | |
1146 | if (err < 0) | |
1147 | goto err_dev_reg; | |
1148 | ||
1149 | subsys->dev_root = dev; | |
1150 | return 0; | |
1151 | ||
1152 | err_dev_reg: | |
1153 | put_device(dev); | |
1154 | dev = NULL; | |
1155 | err_name: | |
1156 | kfree(dev); | |
1157 | err_dev: | |
1158 | bus_unregister(subsys); | |
1159 | return err; | |
1160 | } | |
d73ce004 TH |
1161 | |
1162 | /** | |
1163 | * subsys_system_register - register a subsystem at /sys/devices/system/ | |
1164 | * @subsys: system subsystem | |
1165 | * @groups: default attributes for the root device | |
1166 | * | |
1167 | * All 'system' subsystems have a /sys/devices/system/<name> root device | |
1168 | * with the name of the subsystem. The root device can carry subsystem- | |
1169 | * wide attributes. All registered devices are below this single root | |
1170 | * device and are named after the subsystem with a simple enumeration | |
e227867f | 1171 | * number appended. The registered devices are not explicitly named; |
d73ce004 TH |
1172 | * only 'id' in the device needs to be set. |
1173 | * | |
1174 | * Do not use this interface for anything new, it exists for compatibility | |
1175 | * with bad ideas only. New subsystems should use plain subsystems; and | |
1176 | * add the subsystem-wide attributes should be added to the subsystem | |
1177 | * directory itself and not some create fake root-device placed in | |
1178 | * /sys/devices/system/<name>. | |
1179 | */ | |
1180 | int subsys_system_register(struct bus_type *subsys, | |
1181 | const struct attribute_group **groups) | |
1182 | { | |
1183 | return subsys_register(subsys, groups, &system_kset->kobj); | |
1184 | } | |
ca22e56d KS |
1185 | EXPORT_SYMBOL_GPL(subsys_system_register); |
1186 | ||
d73ce004 TH |
1187 | /** |
1188 | * subsys_virtual_register - register a subsystem at /sys/devices/virtual/ | |
1189 | * @subsys: virtual subsystem | |
1190 | * @groups: default attributes for the root device | |
1191 | * | |
1192 | * All 'virtual' subsystems have a /sys/devices/system/<name> root device | |
1193 | * with the name of the subystem. The root device can carry subsystem-wide | |
1194 | * attributes. All registered devices are below this single root device. | |
1195 | * There's no restriction on device naming. This is for kernel software | |
1196 | * constructs which need sysfs interface. | |
1197 | */ | |
1198 | int subsys_virtual_register(struct bus_type *subsys, | |
1199 | const struct attribute_group **groups) | |
1200 | { | |
1201 | struct kobject *virtual_dir; | |
1202 | ||
1203 | virtual_dir = virtual_device_parent(NULL); | |
1204 | if (!virtual_dir) | |
1205 | return -ENOMEM; | |
1206 | ||
1207 | return subsys_register(subsys, groups, virtual_dir); | |
1208 | } | |
1c04fc35 | 1209 | EXPORT_SYMBOL_GPL(subsys_virtual_register); |
d73ce004 | 1210 | |
1da177e4 LT |
1211 | int __init buses_init(void) |
1212 | { | |
59a54833 GKH |
1213 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1214 | if (!bus_kset) | |
1215 | return -ENOMEM; | |
ca22e56d KS |
1216 | |
1217 | system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); | |
1218 | if (!system_kset) | |
1219 | return -ENOMEM; | |
1220 | ||
59a54833 | 1221 | return 0; |
1da177e4 | 1222 | } |