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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * bus.c - bus driver management | |
3 | * | |
4 | * Copyright (c) 2002-3 Patrick Mochel | |
5 | * Copyright (c) 2002-3 Open Source Development Labs | |
e5dd1278 GKH |
6 | * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de> |
7 | * Copyright (c) 2007 Novell Inc. | |
1da177e4 LT |
8 | * |
9 | * This file is released under the GPLv2 | |
10 | * | |
11 | */ | |
12 | ||
1da177e4 LT |
13 | #include <linux/device.h> |
14 | #include <linux/module.h> | |
15 | #include <linux/errno.h> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
1da177e4 LT |
17 | #include <linux/init.h> |
18 | #include <linux/string.h> | |
ca22e56d | 19 | #include <linux/mutex.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 LT |
33 | |
34 | ||
b8c5cec2 KS |
35 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
36 | void *data); | |
37 | ||
5901d014 GKH |
38 | static struct bus_type *bus_get(struct bus_type *bus) |
39 | { | |
c6f7e72a GKH |
40 | if (bus) { |
41 | kset_get(&bus->p->subsys); | |
42 | return bus; | |
43 | } | |
44 | return NULL; | |
5901d014 GKH |
45 | } |
46 | ||
fc1ede58 GKH |
47 | static void bus_put(struct bus_type *bus) |
48 | { | |
c6f7e72a GKH |
49 | if (bus) |
50 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
51 | } |
52 | ||
4a3ad20c GKH |
53 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
54 | char *buf) | |
1da177e4 | 55 | { |
4a3ad20c | 56 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 57 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 58 | ssize_t ret = -EIO; |
1da177e4 LT |
59 | |
60 | if (drv_attr->show) | |
e5dd1278 | 61 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
62 | return ret; |
63 | } | |
64 | ||
4a3ad20c GKH |
65 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
66 | const char *buf, size_t count) | |
1da177e4 | 67 | { |
4a3ad20c | 68 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 69 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 70 | ssize_t ret = -EIO; |
1da177e4 LT |
71 | |
72 | if (drv_attr->store) | |
e5dd1278 | 73 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
74 | return ret; |
75 | } | |
76 | ||
52cf25d0 | 77 | static const struct sysfs_ops driver_sysfs_ops = { |
1da177e4 LT |
78 | .show = drv_attr_show, |
79 | .store = drv_attr_store, | |
80 | }; | |
81 | ||
e5dd1278 | 82 | static void driver_release(struct kobject *kobj) |
1da177e4 | 83 | { |
e5dd1278 GKH |
84 | struct driver_private *drv_priv = to_driver(kobj); |
85 | ||
2b3a302a | 86 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 87 | kfree(drv_priv); |
1da177e4 LT |
88 | } |
89 | ||
a1148fb0 | 90 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
91 | .sysfs_ops = &driver_sysfs_ops, |
92 | .release = driver_release, | |
93 | }; | |
94 | ||
1da177e4 LT |
95 | /* |
96 | * sysfs bindings for buses | |
97 | */ | |
4a3ad20c GKH |
98 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
99 | char *buf) | |
1da177e4 | 100 | { |
4a3ad20c | 101 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 102 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
103 | ssize_t ret = 0; |
104 | ||
105 | if (bus_attr->show) | |
6b6e39a6 | 106 | ret = bus_attr->show(subsys_priv->bus, buf); |
1da177e4 LT |
107 | return ret; |
108 | } | |
109 | ||
4a3ad20c GKH |
110 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
111 | const char *buf, size_t count) | |
1da177e4 | 112 | { |
4a3ad20c | 113 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 114 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
115 | ssize_t ret = 0; |
116 | ||
117 | if (bus_attr->store) | |
6b6e39a6 | 118 | ret = bus_attr->store(subsys_priv->bus, buf, count); |
1da177e4 LT |
119 | return ret; |
120 | } | |
121 | ||
52cf25d0 | 122 | static const struct sysfs_ops bus_sysfs_ops = { |
1da177e4 LT |
123 | .show = bus_attr_show, |
124 | .store = bus_attr_store, | |
125 | }; | |
126 | ||
4a3ad20c | 127 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
128 | { |
129 | int error; | |
5901d014 | 130 | if (bus_get(bus)) { |
c6f7e72a | 131 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 132 | bus_put(bus); |
1da177e4 LT |
133 | } else |
134 | error = -EINVAL; | |
135 | return error; | |
136 | } | |
4a3ad20c | 137 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 138 | |
4a3ad20c | 139 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 140 | { |
5901d014 | 141 | if (bus_get(bus)) { |
c6f7e72a | 142 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 143 | bus_put(bus); |
1da177e4 LT |
144 | } |
145 | } | |
4a3ad20c | 146 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 147 | |
80f03e34 | 148 | static struct kobj_type bus_ktype = { |
1da177e4 | 149 | .sysfs_ops = &bus_sysfs_ops, |
80f03e34 KS |
150 | }; |
151 | ||
152 | static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) | |
153 | { | |
154 | struct kobj_type *ktype = get_ktype(kobj); | |
155 | ||
156 | if (ktype == &bus_ktype) | |
157 | return 1; | |
158 | return 0; | |
159 | } | |
1da177e4 | 160 | |
9cd43611 | 161 | static const struct kset_uevent_ops bus_uevent_ops = { |
80f03e34 | 162 | .filter = bus_uevent_filter, |
1da177e4 LT |
163 | }; |
164 | ||
59a54833 | 165 | static struct kset *bus_kset; |
1da177e4 | 166 | |
1da177e4 | 167 | |
2139bdd5 | 168 | #ifdef CONFIG_HOTPLUG |
2b08c8d0 | 169 | /* Manually detach a device from its associated driver. */ |
151ef38f GKH |
170 | static ssize_t driver_unbind(struct device_driver *drv, |
171 | const char *buf, size_t count) | |
172 | { | |
5901d014 | 173 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
174 | struct device *dev; |
175 | int err = -ENODEV; | |
176 | ||
1f9ffc04 | 177 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 178 | if (dev && dev->driver == drv) { |
bf74ad5b | 179 | if (dev->parent) /* Needed for USB */ |
8e9394ce | 180 | device_lock(dev->parent); |
151ef38f | 181 | device_release_driver(dev); |
bf74ad5b | 182 | if (dev->parent) |
8e9394ce | 183 | device_unlock(dev->parent); |
151ef38f GKH |
184 | err = count; |
185 | } | |
2b08c8d0 | 186 | put_device(dev); |
fc1ede58 | 187 | bus_put(bus); |
2b08c8d0 | 188 | return err; |
151ef38f GKH |
189 | } |
190 | static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind); | |
191 | ||
afdce75f GKH |
192 | /* |
193 | * Manually attach a device to a driver. | |
194 | * Note: the driver must want to bind to the device, | |
195 | * it is not possible to override the driver's id table. | |
196 | */ | |
197 | static ssize_t driver_bind(struct device_driver *drv, | |
198 | const char *buf, size_t count) | |
199 | { | |
5901d014 | 200 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
201 | struct device *dev; |
202 | int err = -ENODEV; | |
203 | ||
1f9ffc04 | 204 | dev = bus_find_device_by_name(bus, NULL, buf); |
49b420a1 | 205 | if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { |
bf74ad5b | 206 | if (dev->parent) /* Needed for USB */ |
8e9394ce GKH |
207 | device_lock(dev->parent); |
208 | device_lock(dev); | |
afdce75f | 209 | err = driver_probe_device(drv, dev); |
8e9394ce | 210 | device_unlock(dev); |
bf74ad5b | 211 | if (dev->parent) |
8e9394ce | 212 | device_unlock(dev->parent); |
37225401 | 213 | |
4a3ad20c GKH |
214 | if (err > 0) { |
215 | /* success */ | |
37225401 | 216 | err = count; |
4a3ad20c GKH |
217 | } else if (err == 0) { |
218 | /* driver didn't accept device */ | |
37225401 | 219 | err = -ENODEV; |
4a3ad20c | 220 | } |
afdce75f | 221 | } |
2b08c8d0 | 222 | put_device(dev); |
fc1ede58 | 223 | bus_put(bus); |
2b08c8d0 | 224 | return err; |
afdce75f GKH |
225 | } |
226 | static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); | |
227 | ||
b8c5cec2 KS |
228 | static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) |
229 | { | |
c6f7e72a | 230 | return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
231 | } |
232 | ||
233 | static ssize_t store_drivers_autoprobe(struct bus_type *bus, | |
234 | const char *buf, size_t count) | |
235 | { | |
236 | if (buf[0] == '0') | |
c6f7e72a | 237 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 238 | else |
c6f7e72a | 239 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
240 | return count; |
241 | } | |
242 | ||
243 | static ssize_t store_drivers_probe(struct bus_type *bus, | |
244 | const char *buf, size_t count) | |
245 | { | |
246 | struct device *dev; | |
247 | ||
1f9ffc04 | 248 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
249 | if (!dev) |
250 | return -ENODEV; | |
251 | if (bus_rescan_devices_helper(dev, NULL) != 0) | |
252 | return -EINVAL; | |
253 | return count; | |
254 | } | |
2139bdd5 | 255 | #endif |
151ef38f | 256 | |
4a3ad20c | 257 | static struct device *next_device(struct klist_iter *i) |
465c7a3a | 258 | { |
4a3ad20c | 259 | struct klist_node *n = klist_next(i); |
ae1b4171 GKH |
260 | struct device *dev = NULL; |
261 | struct device_private *dev_prv; | |
262 | ||
263 | if (n) { | |
264 | dev_prv = to_device_private_bus(n); | |
265 | dev = dev_prv->device; | |
266 | } | |
267 | return dev; | |
465c7a3a PM |
268 | } |
269 | ||
1da177e4 | 270 | /** |
4a3ad20c GKH |
271 | * bus_for_each_dev - device iterator. |
272 | * @bus: bus type. | |
273 | * @start: device to start iterating from. | |
274 | * @data: data for the callback. | |
275 | * @fn: function to be called for each device. | |
1da177e4 | 276 | * |
4a3ad20c GKH |
277 | * Iterate over @bus's list of devices, and call @fn for each, |
278 | * passing it @data. If @start is not NULL, we use that device to | |
279 | * begin iterating from. | |
1da177e4 | 280 | * |
4a3ad20c GKH |
281 | * We check the return of @fn each time. If it returns anything |
282 | * other than 0, we break out and return that value. | |
1da177e4 | 283 | * |
4a3ad20c GKH |
284 | * NOTE: The device that returns a non-zero value is not retained |
285 | * in any way, nor is its refcount incremented. If the caller needs | |
0fa1b0a1 | 286 | * to retain this data, it should do so, and increment the reference |
4a3ad20c | 287 | * count in the supplied callback. |
1da177e4 | 288 | */ |
4a3ad20c GKH |
289 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
290 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 291 | { |
465c7a3a | 292 | struct klist_iter i; |
4a3ad20c | 293 | struct device *dev; |
465c7a3a | 294 | int error = 0; |
1da177e4 | 295 | |
465c7a3a PM |
296 | if (!bus) |
297 | return -EINVAL; | |
298 | ||
7cd9c9bb GKH |
299 | klist_iter_init_node(&bus->p->klist_devices, &i, |
300 | (start ? &start->p->knode_bus : NULL)); | |
301 | while ((dev = next_device(&i)) && !error) | |
302 | error = fn(dev, data); | |
303 | klist_iter_exit(&i); | |
465c7a3a | 304 | return error; |
1da177e4 | 305 | } |
4a3ad20c | 306 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 307 | |
0edb5860 CH |
308 | /** |
309 | * bus_find_device - device iterator for locating a particular device. | |
310 | * @bus: bus type | |
311 | * @start: Device to begin with | |
312 | * @data: Data to pass to match function | |
313 | * @match: Callback function to check device | |
314 | * | |
315 | * This is similar to the bus_for_each_dev() function above, but it | |
316 | * returns a reference to a device that is 'found' for later use, as | |
317 | * determined by the @match callback. | |
318 | * | |
319 | * The callback should return 0 if the device doesn't match and non-zero | |
320 | * if it does. If the callback returns non-zero, this function will | |
321 | * return to the caller and not iterate over any more devices. | |
322 | */ | |
4a3ad20c GKH |
323 | struct device *bus_find_device(struct bus_type *bus, |
324 | struct device *start, void *data, | |
325 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
326 | { |
327 | struct klist_iter i; | |
328 | struct device *dev; | |
329 | ||
330 | if (!bus) | |
331 | return NULL; | |
332 | ||
7cd9c9bb GKH |
333 | klist_iter_init_node(&bus->p->klist_devices, &i, |
334 | (start ? &start->p->knode_bus : NULL)); | |
0edb5860 CH |
335 | while ((dev = next_device(&i))) |
336 | if (match(dev, data) && get_device(dev)) | |
337 | break; | |
338 | klist_iter_exit(&i); | |
339 | return dev; | |
340 | } | |
4a3ad20c | 341 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 342 | |
1f9ffc04 GKH |
343 | static int match_name(struct device *dev, void *data) |
344 | { | |
345 | const char *name = data; | |
346 | ||
1e0b2cf9 | 347 | return sysfs_streq(name, dev_name(dev)); |
1f9ffc04 GKH |
348 | } |
349 | ||
350 | /** | |
351 | * bus_find_device_by_name - device iterator for locating a particular device of a specific name | |
352 | * @bus: bus type | |
353 | * @start: Device to begin with | |
354 | * @name: name of the device to match | |
355 | * | |
356 | * This is similar to the bus_find_device() function above, but it handles | |
357 | * searching by a name automatically, no need to write another strcmp matching | |
358 | * function. | |
359 | */ | |
360 | struct device *bus_find_device_by_name(struct bus_type *bus, | |
361 | struct device *start, const char *name) | |
362 | { | |
363 | return bus_find_device(bus, start, (void *)name, match_name); | |
364 | } | |
365 | EXPORT_SYMBOL_GPL(bus_find_device_by_name); | |
366 | ||
ca22e56d KS |
367 | /** |
368 | * subsys_find_device_by_id - find a device with a specific enumeration number | |
369 | * @subsys: subsystem | |
370 | * @id: index 'id' in struct device | |
371 | * @hint: device to check first | |
372 | * | |
373 | * Check the hint's next object and if it is a match return it directly, | |
374 | * otherwise, fall back to a full list search. Either way a reference for | |
375 | * the returned object is taken. | |
376 | */ | |
377 | struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, | |
378 | struct device *hint) | |
379 | { | |
380 | struct klist_iter i; | |
381 | struct device *dev; | |
382 | ||
383 | if (!subsys) | |
384 | return NULL; | |
385 | ||
386 | if (hint) { | |
7cd9c9bb | 387 | klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); |
ca22e56d KS |
388 | dev = next_device(&i); |
389 | if (dev && dev->id == id && get_device(dev)) { | |
390 | klist_iter_exit(&i); | |
391 | return dev; | |
392 | } | |
393 | klist_iter_exit(&i); | |
394 | } | |
395 | ||
396 | klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); | |
397 | while ((dev = next_device(&i))) { | |
398 | if (dev->id == id && get_device(dev)) { | |
399 | klist_iter_exit(&i); | |
400 | return dev; | |
401 | } | |
402 | } | |
403 | klist_iter_exit(&i); | |
404 | return NULL; | |
405 | } | |
406 | EXPORT_SYMBOL_GPL(subsys_find_device_by_id); | |
407 | ||
4a3ad20c | 408 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 409 | { |
4a3ad20c | 410 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
411 | struct driver_private *drv_priv; |
412 | ||
413 | if (n) { | |
414 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
415 | return drv_priv->driver; | |
416 | } | |
417 | return NULL; | |
38fdac3c PM |
418 | } |
419 | ||
1da177e4 | 420 | /** |
4a3ad20c GKH |
421 | * bus_for_each_drv - driver iterator |
422 | * @bus: bus we're dealing with. | |
423 | * @start: driver to start iterating on. | |
424 | * @data: data to pass to the callback. | |
425 | * @fn: function to call for each driver. | |
1da177e4 | 426 | * |
4a3ad20c GKH |
427 | * This is nearly identical to the device iterator above. |
428 | * We iterate over each driver that belongs to @bus, and call | |
429 | * @fn for each. If @fn returns anything but 0, we break out | |
430 | * and return it. If @start is not NULL, we use it as the head | |
431 | * of the list. | |
1da177e4 | 432 | * |
4a3ad20c GKH |
433 | * NOTE: we don't return the driver that returns a non-zero |
434 | * value, nor do we leave the reference count incremented for that | |
435 | * driver. If the caller needs to know that info, it must set it | |
436 | * in the callback. It must also be sure to increment the refcount | |
437 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 438 | */ |
4a3ad20c GKH |
439 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
440 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 441 | { |
38fdac3c | 442 | struct klist_iter i; |
4a3ad20c | 443 | struct device_driver *drv; |
38fdac3c | 444 | int error = 0; |
1da177e4 | 445 | |
38fdac3c PM |
446 | if (!bus) |
447 | return -EINVAL; | |
448 | ||
7cd9c9bb GKH |
449 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
450 | start ? &start->p->knode_bus : NULL); | |
451 | while ((drv = next_driver(&i)) && !error) | |
452 | error = fn(drv, data); | |
453 | klist_iter_exit(&i); | |
38fdac3c | 454 | return error; |
1da177e4 | 455 | } |
4a3ad20c | 456 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 457 | |
4aca67e5 | 458 | static int device_add_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
459 | { |
460 | int error = 0; | |
461 | int i; | |
462 | ||
4aca67e5 AM |
463 | if (!bus->dev_attrs) |
464 | return 0; | |
465 | ||
466 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) { | |
4a3ad20c | 467 | error = device_create_file(dev, &bus->dev_attrs[i]); |
4aca67e5 AM |
468 | if (error) { |
469 | while (--i >= 0) | |
470 | device_remove_file(dev, &bus->dev_attrs[i]); | |
471 | break; | |
1da177e4 LT |
472 | } |
473 | } | |
1da177e4 | 474 | return error; |
1da177e4 LT |
475 | } |
476 | ||
4a3ad20c | 477 | static void device_remove_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
478 | { |
479 | int i; | |
480 | ||
481 | if (bus->dev_attrs) { | |
482 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) | |
4a3ad20c | 483 | device_remove_file(dev, &bus->dev_attrs[i]); |
1da177e4 LT |
484 | } |
485 | } | |
486 | ||
1da177e4 | 487 | /** |
4a3ad20c GKH |
488 | * bus_add_device - add device to bus |
489 | * @dev: device being added | |
1da177e4 | 490 | * |
2023c610 AS |
491 | * - Add device's bus attributes. |
492 | * - Create links to device's bus. | |
4a3ad20c | 493 | * - Add the device to its bus's list of devices. |
1da177e4 | 494 | */ |
4a3ad20c | 495 | int bus_add_device(struct device *dev) |
1da177e4 | 496 | { |
4a3ad20c | 497 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
498 | int error = 0; |
499 | ||
500 | if (bus) { | |
1e0b2cf9 | 501 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
d377e85b | 502 | error = device_add_attrs(bus, dev); |
f86db396 | 503 | if (error) |
513e7337 | 504 | goto out_put; |
c6f7e72a | 505 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 506 | &dev->kobj, dev_name(dev)); |
f86db396 | 507 | if (error) |
513e7337 | 508 | goto out_id; |
f86db396 | 509 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 510 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 511 | if (error) |
513e7337 | 512 | goto out_subsys; |
2023c610 | 513 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 514 | } |
513e7337 CH |
515 | return 0; |
516 | ||
513e7337 | 517 | out_subsys: |
1e0b2cf9 | 518 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
513e7337 CH |
519 | out_id: |
520 | device_remove_attrs(bus, dev); | |
521 | out_put: | |
fc1ede58 | 522 | bus_put(dev->bus); |
1da177e4 LT |
523 | return error; |
524 | } | |
525 | ||
53877d06 | 526 | /** |
2023c610 AS |
527 | * bus_probe_device - probe drivers for a new device |
528 | * @dev: device to probe | |
53877d06 | 529 | * |
2023c610 | 530 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 531 | */ |
2023c610 | 532 | void bus_probe_device(struct device *dev) |
53877d06 | 533 | { |
f86db396 | 534 | struct bus_type *bus = dev->bus; |
ca22e56d | 535 | struct subsys_interface *sif; |
2023c610 | 536 | int ret; |
53877d06 | 537 | |
ca22e56d KS |
538 | if (!bus) |
539 | return; | |
540 | ||
541 | if (bus->p->drivers_autoprobe) { | |
2023c610 | 542 | ret = device_attach(dev); |
c6a46696 | 543 | WARN_ON(ret < 0); |
53877d06 | 544 | } |
ca22e56d KS |
545 | |
546 | mutex_lock(&bus->p->mutex); | |
547 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
548 | if (sif->add_dev) | |
549 | sif->add_dev(dev, sif); | |
550 | mutex_unlock(&bus->p->mutex); | |
53877d06 KS |
551 | } |
552 | ||
1da177e4 | 553 | /** |
4a3ad20c GKH |
554 | * bus_remove_device - remove device from bus |
555 | * @dev: device to be removed | |
1da177e4 | 556 | * |
ca22e56d KS |
557 | * - Remove device from all interfaces. |
558 | * - Remove symlink from bus' directory. | |
4a3ad20c GKH |
559 | * - Delete device from bus's list. |
560 | * - Detach from its driver. | |
561 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 562 | */ |
4a3ad20c | 563 | void bus_remove_device(struct device *dev) |
1da177e4 | 564 | { |
ca22e56d KS |
565 | struct bus_type *bus = dev->bus; |
566 | struct subsys_interface *sif; | |
567 | ||
568 | if (!bus) | |
569 | return; | |
570 | ||
571 | mutex_lock(&bus->p->mutex); | |
572 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
573 | if (sif->remove_dev) | |
574 | sif->remove_dev(dev, sif); | |
575 | mutex_unlock(&bus->p->mutex); | |
576 | ||
577 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
578 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, | |
579 | dev_name(dev)); | |
580 | device_remove_attrs(dev->bus, dev); | |
581 | if (klist_node_attached(&dev->p->knode_bus)) | |
582 | klist_del(&dev->p->knode_bus); | |
583 | ||
584 | pr_debug("bus: '%s': remove device %s\n", | |
585 | dev->bus->name, dev_name(dev)); | |
586 | device_release_driver(dev); | |
587 | bus_put(dev->bus); | |
1da177e4 LT |
588 | } |
589 | ||
4a3ad20c | 590 | static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv) |
1da177e4 LT |
591 | { |
592 | int error = 0; | |
593 | int i; | |
594 | ||
595 | if (bus->drv_attrs) { | |
596 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) { | |
597 | error = driver_create_file(drv, &bus->drv_attrs[i]); | |
598 | if (error) | |
4a3ad20c | 599 | goto err; |
1da177e4 LT |
600 | } |
601 | } | |
4a3ad20c | 602 | done: |
1da177e4 | 603 | return error; |
4a3ad20c | 604 | err: |
1da177e4 LT |
605 | while (--i >= 0) |
606 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
4a3ad20c | 607 | goto done; |
1da177e4 LT |
608 | } |
609 | ||
4a3ad20c GKH |
610 | static void driver_remove_attrs(struct bus_type *bus, |
611 | struct device_driver *drv) | |
1da177e4 LT |
612 | { |
613 | int i; | |
614 | ||
615 | if (bus->drv_attrs) { | |
616 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) | |
617 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
618 | } | |
619 | } | |
620 | ||
874c6241 GKH |
621 | #ifdef CONFIG_HOTPLUG |
622 | /* | |
623 | * Thanks to drivers making their tables __devinit, we can't allow manual | |
624 | * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. | |
625 | */ | |
f86db396 | 626 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 627 | { |
f86db396 AM |
628 | int ret; |
629 | ||
630 | ret = driver_create_file(drv, &driver_attr_unbind); | |
631 | if (ret == 0) { | |
632 | ret = driver_create_file(drv, &driver_attr_bind); | |
633 | if (ret) | |
634 | driver_remove_file(drv, &driver_attr_unbind); | |
635 | } | |
636 | return ret; | |
874c6241 GKH |
637 | } |
638 | ||
639 | static void remove_bind_files(struct device_driver *drv) | |
640 | { | |
641 | driver_remove_file(drv, &driver_attr_bind); | |
642 | driver_remove_file(drv, &driver_attr_unbind); | |
643 | } | |
b8c5cec2 | 644 | |
8380770c KS |
645 | static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); |
646 | static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, | |
647 | show_drivers_autoprobe, store_drivers_autoprobe); | |
648 | ||
b8c5cec2 KS |
649 | static int add_probe_files(struct bus_type *bus) |
650 | { | |
651 | int retval; | |
652 | ||
8380770c | 653 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
654 | if (retval) |
655 | goto out; | |
656 | ||
8380770c | 657 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 658 | if (retval) |
8380770c | 659 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
660 | out: |
661 | return retval; | |
662 | } | |
663 | ||
664 | static void remove_probe_files(struct bus_type *bus) | |
665 | { | |
8380770c KS |
666 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
667 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 668 | } |
874c6241 | 669 | #else |
35acfdd7 | 670 | static inline int add_bind_files(struct device_driver *drv) { return 0; } |
874c6241 | 671 | static inline void remove_bind_files(struct device_driver *drv) {} |
b8c5cec2 KS |
672 | static inline int add_probe_files(struct bus_type *bus) { return 0; } |
673 | static inline void remove_probe_files(struct bus_type *bus) {} | |
874c6241 | 674 | #endif |
1da177e4 | 675 | |
7ac1cf4a KS |
676 | static ssize_t driver_uevent_store(struct device_driver *drv, |
677 | const char *buf, size_t count) | |
678 | { | |
679 | enum kobject_action action; | |
680 | ||
681 | if (kobject_action_type(buf, count, &action) == 0) | |
e5dd1278 | 682 | kobject_uevent(&drv->p->kobj, action); |
7ac1cf4a KS |
683 | return count; |
684 | } | |
685 | static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store); | |
686 | ||
1da177e4 | 687 | /** |
4a3ad20c GKH |
688 | * bus_add_driver - Add a driver to the bus. |
689 | * @drv: driver. | |
1da177e4 | 690 | */ |
f86db396 | 691 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 692 | { |
e5dd1278 GKH |
693 | struct bus_type *bus; |
694 | struct driver_private *priv; | |
1da177e4 LT |
695 | int error = 0; |
696 | ||
e5dd1278 | 697 | bus = bus_get(drv->bus); |
d9fd4d3b | 698 | if (!bus) |
4f6e1945 | 699 | return -EINVAL; |
d9fd4d3b | 700 | |
7dc72b28 | 701 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
702 | |
703 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
704 | if (!priv) { |
705 | error = -ENOMEM; | |
706 | goto out_put_bus; | |
707 | } | |
e5dd1278 GKH |
708 | klist_init(&priv->klist_devices, NULL, NULL); |
709 | priv->driver = drv; | |
710 | drv->p = priv; | |
c8e90d82 GKH |
711 | priv->kobj.kset = bus->p->drivers_kset; |
712 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
713 | "%s", drv->name); | |
dc0afa83 | 714 | if (error) |
07634464 | 715 | goto out_unregister; |
d9fd4d3b | 716 | |
c6f7e72a | 717 | if (drv->bus->p->drivers_autoprobe) { |
b8c5cec2 KS |
718 | error = driver_attach(drv); |
719 | if (error) | |
720 | goto out_unregister; | |
721 | } | |
e5dd1278 | 722 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
d9fd4d3b JG |
723 | module_add_driver(drv->owner, drv); |
724 | ||
7ac1cf4a KS |
725 | error = driver_create_file(drv, &driver_attr_uevent); |
726 | if (error) { | |
727 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 728 | __func__, drv->name); |
7ac1cf4a | 729 | } |
d9fd4d3b JG |
730 | error = driver_add_attrs(bus, drv); |
731 | if (error) { | |
732 | /* How the hell do we get out of this pickle? Give up */ | |
733 | printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", | |
2b3a302a | 734 | __func__, drv->name); |
d9fd4d3b | 735 | } |
1a6f2a75 DT |
736 | |
737 | if (!drv->suppress_bind_attrs) { | |
738 | error = add_bind_files(drv); | |
739 | if (error) { | |
740 | /* Ditto */ | |
741 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
742 | __func__, drv->name); | |
743 | } | |
1da177e4 | 744 | } |
d9fd4d3b | 745 | |
c8e90d82 | 746 | kobject_uevent(&priv->kobj, KOBJ_ADD); |
5c8563d7 | 747 | return 0; |
1a6f2a75 | 748 | |
f86db396 | 749 | out_unregister: |
99b28f1b | 750 | kobject_put(&priv->kobj); |
5c8563d7 KS |
751 | kfree(drv->p); |
752 | drv->p = NULL; | |
f86db396 | 753 | out_put_bus: |
fc1ede58 | 754 | bus_put(bus); |
f86db396 | 755 | return error; |
1da177e4 LT |
756 | } |
757 | ||
1da177e4 | 758 | /** |
4a3ad20c GKH |
759 | * bus_remove_driver - delete driver from bus's knowledge. |
760 | * @drv: driver. | |
1da177e4 | 761 | * |
4a3ad20c GKH |
762 | * Detach the driver from the devices it controls, and remove |
763 | * it from its bus's list of drivers. Finally, we drop the reference | |
764 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 765 | */ |
4a3ad20c | 766 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 767 | { |
d9fd4d3b JG |
768 | if (!drv->bus) |
769 | return; | |
770 | ||
1a6f2a75 DT |
771 | if (!drv->suppress_bind_attrs) |
772 | remove_bind_files(drv); | |
d9fd4d3b | 773 | driver_remove_attrs(drv->bus, drv); |
7ac1cf4a | 774 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 775 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 776 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
777 | driver_detach(drv); |
778 | module_remove_driver(drv); | |
c10997f6 | 779 | kobject_put(&drv->p->kobj); |
fc1ede58 | 780 | bus_put(drv->bus); |
1da177e4 LT |
781 | } |
782 | ||
1da177e4 | 783 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 784 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 785 | void *data) |
1da177e4 | 786 | { |
f86db396 AM |
787 | int ret = 0; |
788 | ||
bf74ad5b AS |
789 | if (!dev->driver) { |
790 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 791 | device_lock(dev->parent); |
f86db396 | 792 | ret = device_attach(dev); |
bf74ad5b | 793 | if (dev->parent) |
8e9394ce | 794 | device_unlock(dev->parent); |
bf74ad5b | 795 | } |
f86db396 | 796 | return ret < 0 ? ret : 0; |
1da177e4 LT |
797 | } |
798 | ||
1da177e4 | 799 | /** |
23d3d602 GKH |
800 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
801 | * @bus: the bus to scan. | |
1da177e4 | 802 | * |
23d3d602 GKH |
803 | * This function will look for devices on the bus with no driver |
804 | * attached and rescan it against existing drivers to see if it matches | |
805 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 806 | */ |
4a3ad20c | 807 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 808 | { |
f86db396 | 809 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 810 | } |
4a3ad20c | 811 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 812 | |
e935d5da ME |
813 | /** |
814 | * device_reprobe - remove driver for a device and probe for a new driver | |
815 | * @dev: the device to reprobe | |
816 | * | |
817 | * This function detaches the attached driver (if any) for the given | |
818 | * device and restarts the driver probing process. It is intended | |
819 | * to use if probing criteria changed during a devices lifetime and | |
820 | * driver attachment should change accordingly. | |
821 | */ | |
f86db396 | 822 | int device_reprobe(struct device *dev) |
e935d5da ME |
823 | { |
824 | if (dev->driver) { | |
825 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 826 | device_lock(dev->parent); |
e935d5da ME |
827 | device_release_driver(dev); |
828 | if (dev->parent) | |
8e9394ce | 829 | device_unlock(dev->parent); |
e935d5da | 830 | } |
f86db396 | 831 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
832 | } |
833 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 834 | |
1da177e4 | 835 | /** |
4a3ad20c GKH |
836 | * find_bus - locate bus by name. |
837 | * @name: name of bus. | |
1da177e4 | 838 | * |
4a3ad20c GKH |
839 | * Call kset_find_obj() to iterate over list of buses to |
840 | * find a bus by name. Return bus if found. | |
1da177e4 | 841 | * |
4a3ad20c | 842 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 843 | */ |
7e4ef085 | 844 | #if 0 |
4a3ad20c | 845 | struct bus_type *find_bus(char *name) |
1da177e4 | 846 | { |
4a3ad20c | 847 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
848 | return k ? to_bus(k) : NULL; |
849 | } | |
7e4ef085 | 850 | #endif /* 0 */ |
1da177e4 LT |
851 | |
852 | ||
853 | /** | |
4a3ad20c GKH |
854 | * bus_add_attrs - Add default attributes for this bus. |
855 | * @bus: Bus that has just been registered. | |
1da177e4 LT |
856 | */ |
857 | ||
4a3ad20c | 858 | static int bus_add_attrs(struct bus_type *bus) |
1da177e4 LT |
859 | { |
860 | int error = 0; | |
861 | int i; | |
862 | ||
863 | if (bus->bus_attrs) { | |
864 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) { | |
4a3ad20c | 865 | error = bus_create_file(bus, &bus->bus_attrs[i]); |
dc0afa83 | 866 | if (error) |
4a3ad20c | 867 | goto err; |
1da177e4 LT |
868 | } |
869 | } | |
4a3ad20c | 870 | done: |
1da177e4 | 871 | return error; |
4a3ad20c | 872 | err: |
1da177e4 | 873 | while (--i >= 0) |
4a3ad20c GKH |
874 | bus_remove_file(bus, &bus->bus_attrs[i]); |
875 | goto done; | |
1da177e4 LT |
876 | } |
877 | ||
4a3ad20c | 878 | static void bus_remove_attrs(struct bus_type *bus) |
1da177e4 LT |
879 | { |
880 | int i; | |
881 | ||
882 | if (bus->bus_attrs) { | |
883 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) | |
4a3ad20c | 884 | bus_remove_file(bus, &bus->bus_attrs[i]); |
1da177e4 LT |
885 | } |
886 | } | |
887 | ||
34bb61f9 JB |
888 | static void klist_devices_get(struct klist_node *n) |
889 | { | |
ae1b4171 GKH |
890 | struct device_private *dev_prv = to_device_private_bus(n); |
891 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
892 | |
893 | get_device(dev); | |
894 | } | |
895 | ||
896 | static void klist_devices_put(struct klist_node *n) | |
897 | { | |
ae1b4171 GKH |
898 | struct device_private *dev_prv = to_device_private_bus(n); |
899 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
900 | |
901 | put_device(dev); | |
902 | } | |
903 | ||
7ac1cf4a KS |
904 | static ssize_t bus_uevent_store(struct bus_type *bus, |
905 | const char *buf, size_t count) | |
906 | { | |
907 | enum kobject_action action; | |
908 | ||
909 | if (kobject_action_type(buf, count, &action) == 0) | |
c6f7e72a | 910 | kobject_uevent(&bus->p->subsys.kobj, action); |
7ac1cf4a KS |
911 | return count; |
912 | } | |
913 | static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); | |
914 | ||
1da177e4 | 915 | /** |
ca22e56d | 916 | * __bus_register - register a driver-core subsystem |
78d79559 RD |
917 | * @bus: bus to register |
918 | * @key: lockdep class key | |
1da177e4 | 919 | * |
78d79559 | 920 | * Once we have that, we register the bus with the kobject |
4a3ad20c | 921 | * infrastructure, then register the children subsystems it has: |
ca22e56d | 922 | * the devices and drivers that belong to the subsystem. |
1da177e4 | 923 | */ |
ca22e56d | 924 | int __bus_register(struct bus_type *bus, struct lock_class_key *key) |
1da177e4 LT |
925 | { |
926 | int retval; | |
6b6e39a6 | 927 | struct subsys_private *priv; |
c6f7e72a | 928 | |
6b6e39a6 | 929 | priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL); |
c6f7e72a GKH |
930 | if (!priv) |
931 | return -ENOMEM; | |
932 | ||
933 | priv->bus = bus; | |
934 | bus->p = priv; | |
1da177e4 | 935 | |
c6f7e72a | 936 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 937 | |
c6f7e72a | 938 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
939 | if (retval) |
940 | goto out; | |
941 | ||
c6f7e72a GKH |
942 | priv->subsys.kobj.kset = bus_kset; |
943 | priv->subsys.kobj.ktype = &bus_ktype; | |
944 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 945 | |
c6f7e72a | 946 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
947 | if (retval) |
948 | goto out; | |
949 | ||
7ac1cf4a KS |
950 | retval = bus_create_file(bus, &bus_attr_uevent); |
951 | if (retval) | |
952 | goto bus_uevent_fail; | |
953 | ||
c6f7e72a GKH |
954 | priv->devices_kset = kset_create_and_add("devices", NULL, |
955 | &priv->subsys.kobj); | |
956 | if (!priv->devices_kset) { | |
3d899596 | 957 | retval = -ENOMEM; |
1da177e4 | 958 | goto bus_devices_fail; |
3d899596 | 959 | } |
1da177e4 | 960 | |
c6f7e72a GKH |
961 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
962 | &priv->subsys.kobj); | |
963 | if (!priv->drivers_kset) { | |
6dcec251 | 964 | retval = -ENOMEM; |
1da177e4 | 965 | goto bus_drivers_fail; |
6dcec251 | 966 | } |
465c7a3a | 967 | |
ca22e56d KS |
968 | INIT_LIST_HEAD(&priv->interfaces); |
969 | __mutex_init(&priv->mutex, "subsys mutex", key); | |
c6f7e72a GKH |
970 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
971 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 972 | |
b8c5cec2 KS |
973 | retval = add_probe_files(bus); |
974 | if (retval) | |
975 | goto bus_probe_files_fail; | |
976 | ||
1bb6881a CH |
977 | retval = bus_add_attrs(bus); |
978 | if (retval) | |
979 | goto bus_attrs_fail; | |
1da177e4 | 980 | |
7dc72b28 | 981 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
982 | return 0; |
983 | ||
1bb6881a | 984 | bus_attrs_fail: |
b8c5cec2 KS |
985 | remove_probe_files(bus); |
986 | bus_probe_files_fail: | |
c6f7e72a | 987 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 988 | bus_drivers_fail: |
c6f7e72a | 989 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 990 | bus_devices_fail: |
7ac1cf4a KS |
991 | bus_remove_file(bus, &bus_attr_uevent); |
992 | bus_uevent_fail: | |
c6f7e72a | 993 | kset_unregister(&bus->p->subsys); |
1da177e4 | 994 | out: |
600c20f3 | 995 | kfree(bus->p); |
f48f3feb | 996 | bus->p = NULL; |
1da177e4 LT |
997 | return retval; |
998 | } | |
ca22e56d | 999 | EXPORT_SYMBOL_GPL(__bus_register); |
1da177e4 | 1000 | |
1da177e4 | 1001 | /** |
4a3ad20c GKH |
1002 | * bus_unregister - remove a bus from the system |
1003 | * @bus: bus. | |
1da177e4 | 1004 | * |
4a3ad20c GKH |
1005 | * Unregister the child subsystems and the bus itself. |
1006 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 1007 | */ |
4a3ad20c | 1008 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 1009 | { |
7dc72b28 | 1010 | pr_debug("bus: '%s': unregistering\n", bus->name); |
ca22e56d KS |
1011 | if (bus->dev_root) |
1012 | device_unregister(bus->dev_root); | |
1da177e4 | 1013 | bus_remove_attrs(bus); |
b8c5cec2 | 1014 | remove_probe_files(bus); |
c6f7e72a GKH |
1015 | kset_unregister(bus->p->drivers_kset); |
1016 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 1017 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a GKH |
1018 | kset_unregister(&bus->p->subsys); |
1019 | kfree(bus->p); | |
f48f3feb | 1020 | bus->p = NULL; |
1da177e4 | 1021 | } |
4a3ad20c | 1022 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 1023 | |
116af378 BH |
1024 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
1025 | { | |
c6f7e72a | 1026 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
1027 | } |
1028 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
1029 | ||
1030 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
1031 | { | |
c6f7e72a | 1032 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
1033 | } |
1034 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
1035 | ||
0fed80f7 GKH |
1036 | struct kset *bus_get_kset(struct bus_type *bus) |
1037 | { | |
c6f7e72a | 1038 | return &bus->p->subsys; |
0fed80f7 GKH |
1039 | } |
1040 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
1041 | ||
b249072e GKH |
1042 | struct klist *bus_get_device_klist(struct bus_type *bus) |
1043 | { | |
c6f7e72a | 1044 | return &bus->p->klist_devices; |
b249072e GKH |
1045 | } |
1046 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
1047 | ||
99178b03 | 1048 | /* |
dca25ebd | 1049 | * Yes, this forcibly breaks the klist abstraction temporarily. It |
99178b03 GKH |
1050 | * just wants to sort the klist, not change reference counts and |
1051 | * take/drop locks rapidly in the process. It does all this while | |
1052 | * holding the lock for the list, so objects can't otherwise be | |
1053 | * added/removed while we're swizzling. | |
1054 | */ | |
1055 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
1056 | int (*compare)(const struct device *a, | |
1057 | const struct device *b)) | |
1058 | { | |
1059 | struct list_head *pos; | |
1060 | struct klist_node *n; | |
ae1b4171 | 1061 | struct device_private *dev_prv; |
99178b03 GKH |
1062 | struct device *b; |
1063 | ||
1064 | list_for_each(pos, list) { | |
1065 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1066 | dev_prv = to_device_private_bus(n); |
1067 | b = dev_prv->device; | |
99178b03 | 1068 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
1069 | list_move_tail(&a->p->knode_bus.n_node, |
1070 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
1071 | return; |
1072 | } | |
1073 | } | |
ae1b4171 | 1074 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
1075 | } |
1076 | ||
1077 | void bus_sort_breadthfirst(struct bus_type *bus, | |
1078 | int (*compare)(const struct device *a, | |
1079 | const struct device *b)) | |
1080 | { | |
1081 | LIST_HEAD(sorted_devices); | |
1082 | struct list_head *pos, *tmp; | |
1083 | struct klist_node *n; | |
ae1b4171 | 1084 | struct device_private *dev_prv; |
99178b03 GKH |
1085 | struct device *dev; |
1086 | struct klist *device_klist; | |
1087 | ||
1088 | device_klist = bus_get_device_klist(bus); | |
1089 | ||
1090 | spin_lock(&device_klist->k_lock); | |
1091 | list_for_each_safe(pos, tmp, &device_klist->k_list) { | |
1092 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1093 | dev_prv = to_device_private_bus(n); |
1094 | dev = dev_prv->device; | |
99178b03 GKH |
1095 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
1096 | } | |
1097 | list_splice(&sorted_devices, &device_klist->k_list); | |
1098 | spin_unlock(&device_klist->k_lock); | |
1099 | } | |
1100 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
1101 | ||
ca22e56d KS |
1102 | /** |
1103 | * subsys_dev_iter_init - initialize subsys device iterator | |
1104 | * @iter: subsys iterator to initialize | |
1105 | * @subsys: the subsys we wanna iterate over | |
1106 | * @start: the device to start iterating from, if any | |
1107 | * @type: device_type of the devices to iterate over, NULL for all | |
1108 | * | |
1109 | * Initialize subsys iterator @iter such that it iterates over devices | |
1110 | * of @subsys. If @start is set, the list iteration will start there, | |
1111 | * otherwise if it is NULL, the iteration starts at the beginning of | |
1112 | * the list. | |
1113 | */ | |
7cd9c9bb GKH |
1114 | void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys, |
1115 | struct device *start, const struct device_type *type) | |
ca22e56d KS |
1116 | { |
1117 | struct klist_node *start_knode = NULL; | |
1118 | ||
1119 | if (start) | |
1120 | start_knode = &start->p->knode_bus; | |
7cd9c9bb GKH |
1121 | klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode); |
1122 | iter->type = type; | |
ca22e56d KS |
1123 | } |
1124 | EXPORT_SYMBOL_GPL(subsys_dev_iter_init); | |
1125 | ||
1126 | /** | |
1127 | * subsys_dev_iter_next - iterate to the next device | |
1128 | * @iter: subsys iterator to proceed | |
1129 | * | |
1130 | * Proceed @iter to the next device and return it. Returns NULL if | |
1131 | * iteration is complete. | |
1132 | * | |
1133 | * The returned device is referenced and won't be released till | |
1134 | * iterator is proceed to the next device or exited. The caller is | |
1135 | * free to do whatever it wants to do with the device including | |
1136 | * calling back into subsys code. | |
1137 | */ | |
1138 | struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter) | |
1139 | { | |
1140 | struct klist_node *knode; | |
1141 | struct device *dev; | |
1142 | ||
1143 | for (;;) { | |
1144 | knode = klist_next(&iter->ki); | |
1145 | if (!knode) | |
1146 | return NULL; | |
1147 | dev = container_of(knode, struct device_private, knode_bus)->device; | |
1148 | if (!iter->type || iter->type == dev->type) | |
1149 | return dev; | |
1150 | } | |
1151 | } | |
1152 | EXPORT_SYMBOL_GPL(subsys_dev_iter_next); | |
1153 | ||
1154 | /** | |
1155 | * subsys_dev_iter_exit - finish iteration | |
1156 | * @iter: subsys iterator to finish | |
1157 | * | |
1158 | * Finish an iteration. Always call this function after iteration is | |
1159 | * complete whether the iteration ran till the end or not. | |
1160 | */ | |
1161 | void subsys_dev_iter_exit(struct subsys_dev_iter *iter) | |
1162 | { | |
1163 | klist_iter_exit(&iter->ki); | |
1164 | } | |
1165 | EXPORT_SYMBOL_GPL(subsys_dev_iter_exit); | |
1166 | ||
1167 | int subsys_interface_register(struct subsys_interface *sif) | |
1168 | { | |
1169 | struct bus_type *subsys; | |
1170 | struct subsys_dev_iter iter; | |
1171 | struct device *dev; | |
1172 | ||
1173 | if (!sif || !sif->subsys) | |
1174 | return -ENODEV; | |
1175 | ||
1176 | subsys = bus_get(sif->subsys); | |
1177 | if (!subsys) | |
1178 | return -EINVAL; | |
1179 | ||
1180 | mutex_lock(&subsys->p->mutex); | |
1181 | list_add_tail(&sif->node, &subsys->p->interfaces); | |
1182 | if (sif->add_dev) { | |
1183 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1184 | while ((dev = subsys_dev_iter_next(&iter))) | |
1185 | sif->add_dev(dev, sif); | |
1186 | subsys_dev_iter_exit(&iter); | |
1187 | } | |
1188 | mutex_unlock(&subsys->p->mutex); | |
1189 | ||
1190 | return 0; | |
1191 | } | |
1192 | EXPORT_SYMBOL_GPL(subsys_interface_register); | |
1193 | ||
1194 | void subsys_interface_unregister(struct subsys_interface *sif) | |
1195 | { | |
2b31594a | 1196 | struct bus_type *subsys; |
ca22e56d KS |
1197 | struct subsys_dev_iter iter; |
1198 | struct device *dev; | |
1199 | ||
2b31594a | 1200 | if (!sif || !sif->subsys) |
ca22e56d KS |
1201 | return; |
1202 | ||
2b31594a JC |
1203 | subsys = sif->subsys; |
1204 | ||
ca22e56d KS |
1205 | mutex_lock(&subsys->p->mutex); |
1206 | list_del_init(&sif->node); | |
1207 | if (sif->remove_dev) { | |
1208 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1209 | while ((dev = subsys_dev_iter_next(&iter))) | |
1210 | sif->remove_dev(dev, sif); | |
1211 | subsys_dev_iter_exit(&iter); | |
1212 | } | |
1213 | mutex_unlock(&subsys->p->mutex); | |
1214 | ||
1215 | bus_put(subsys); | |
1216 | } | |
1217 | EXPORT_SYMBOL_GPL(subsys_interface_unregister); | |
1218 | ||
1219 | static void system_root_device_release(struct device *dev) | |
1220 | { | |
1221 | kfree(dev); | |
1222 | } | |
1223 | /** | |
1224 | * subsys_system_register - register a subsystem at /sys/devices/system/ | |
78d79559 RD |
1225 | * @subsys: system subsystem |
1226 | * @groups: default attributes for the root device | |
ca22e56d KS |
1227 | * |
1228 | * All 'system' subsystems have a /sys/devices/system/<name> root device | |
1229 | * with the name of the subsystem. The root device can carry subsystem- | |
1230 | * wide attributes. All registered devices are below this single root | |
1231 | * device and are named after the subsystem with a simple enumeration | |
1232 | * number appended. The registered devices are not explicitely named; | |
1233 | * only 'id' in the device needs to be set. | |
1234 | * | |
1235 | * Do not use this interface for anything new, it exists for compatibility | |
1236 | * with bad ideas only. New subsystems should use plain subsystems; and | |
1237 | * add the subsystem-wide attributes should be added to the subsystem | |
1238 | * directory itself and not some create fake root-device placed in | |
1239 | * /sys/devices/system/<name>. | |
1240 | */ | |
1241 | int subsys_system_register(struct bus_type *subsys, | |
1242 | const struct attribute_group **groups) | |
1243 | { | |
1244 | struct device *dev; | |
1245 | int err; | |
1246 | ||
1247 | err = bus_register(subsys); | |
1248 | if (err < 0) | |
1249 | return err; | |
1250 | ||
1251 | dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
1252 | if (!dev) { | |
1253 | err = -ENOMEM; | |
1254 | goto err_dev; | |
1255 | } | |
1256 | ||
1257 | err = dev_set_name(dev, "%s", subsys->name); | |
1258 | if (err < 0) | |
1259 | goto err_name; | |
1260 | ||
1261 | dev->kobj.parent = &system_kset->kobj; | |
1262 | dev->groups = groups; | |
1263 | dev->release = system_root_device_release; | |
1264 | ||
1265 | err = device_register(dev); | |
1266 | if (err < 0) | |
1267 | goto err_dev_reg; | |
1268 | ||
1269 | subsys->dev_root = dev; | |
1270 | return 0; | |
1271 | ||
1272 | err_dev_reg: | |
1273 | put_device(dev); | |
1274 | dev = NULL; | |
1275 | err_name: | |
1276 | kfree(dev); | |
1277 | err_dev: | |
1278 | bus_unregister(subsys); | |
1279 | return err; | |
1280 | } | |
1281 | EXPORT_SYMBOL_GPL(subsys_system_register); | |
1282 | ||
1da177e4 LT |
1283 | int __init buses_init(void) |
1284 | { | |
59a54833 GKH |
1285 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1286 | if (!bus_kset) | |
1287 | return -ENOMEM; | |
ca22e56d KS |
1288 | |
1289 | system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); | |
1290 | if (!system_kset) | |
1291 | return -ENOMEM; | |
1292 | ||
59a54833 | 1293 | return 0; |
1da177e4 | 1294 | } |