Commit | Line | Data |
---|---|---|
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> | |
16 | #include <linux/init.h> | |
17 | #include <linux/string.h> | |
18 | #include "base.h" | |
19 | #include "power/power.h" | |
20 | ||
1da177e4 | 21 | #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) |
c6f7e72a | 22 | #define to_bus(obj) container_of(obj, struct bus_type_private, subsys.kobj) |
1da177e4 LT |
23 | |
24 | /* | |
25 | * sysfs bindings for drivers | |
26 | */ | |
27 | ||
28 | #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) | |
1da177e4 LT |
29 | |
30 | ||
b8c5cec2 KS |
31 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
32 | void *data); | |
33 | ||
5901d014 GKH |
34 | static struct bus_type *bus_get(struct bus_type *bus) |
35 | { | |
c6f7e72a GKH |
36 | if (bus) { |
37 | kset_get(&bus->p->subsys); | |
38 | return bus; | |
39 | } | |
40 | return NULL; | |
5901d014 GKH |
41 | } |
42 | ||
fc1ede58 GKH |
43 | static void bus_put(struct bus_type *bus) |
44 | { | |
c6f7e72a GKH |
45 | if (bus) |
46 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
47 | } |
48 | ||
4a3ad20c GKH |
49 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
50 | char *buf) | |
1da177e4 | 51 | { |
4a3ad20c | 52 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 53 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 54 | ssize_t ret = -EIO; |
1da177e4 LT |
55 | |
56 | if (drv_attr->show) | |
e5dd1278 | 57 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
58 | return ret; |
59 | } | |
60 | ||
4a3ad20c GKH |
61 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
62 | const char *buf, size_t count) | |
1da177e4 | 63 | { |
4a3ad20c | 64 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 65 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 66 | ssize_t ret = -EIO; |
1da177e4 LT |
67 | |
68 | if (drv_attr->store) | |
e5dd1278 | 69 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
70 | return ret; |
71 | } | |
72 | ||
73 | static struct sysfs_ops driver_sysfs_ops = { | |
74 | .show = drv_attr_show, | |
75 | .store = drv_attr_store, | |
76 | }; | |
77 | ||
e5dd1278 | 78 | static void driver_release(struct kobject *kobj) |
1da177e4 | 79 | { |
e5dd1278 GKH |
80 | struct driver_private *drv_priv = to_driver(kobj); |
81 | ||
2b3a302a | 82 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 83 | kfree(drv_priv); |
1da177e4 LT |
84 | } |
85 | ||
a1148fb0 | 86 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
87 | .sysfs_ops = &driver_sysfs_ops, |
88 | .release = driver_release, | |
89 | }; | |
90 | ||
1da177e4 LT |
91 | /* |
92 | * sysfs bindings for buses | |
93 | */ | |
4a3ad20c GKH |
94 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
95 | char *buf) | |
1da177e4 | 96 | { |
4a3ad20c | 97 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
c6f7e72a | 98 | struct bus_type_private *bus_priv = to_bus(kobj); |
1da177e4 LT |
99 | ssize_t ret = 0; |
100 | ||
101 | if (bus_attr->show) | |
c6f7e72a | 102 | ret = bus_attr->show(bus_priv->bus, buf); |
1da177e4 LT |
103 | return ret; |
104 | } | |
105 | ||
4a3ad20c GKH |
106 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
107 | const char *buf, size_t count) | |
1da177e4 | 108 | { |
4a3ad20c | 109 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
c6f7e72a | 110 | struct bus_type_private *bus_priv = to_bus(kobj); |
1da177e4 LT |
111 | ssize_t ret = 0; |
112 | ||
113 | if (bus_attr->store) | |
c6f7e72a | 114 | ret = bus_attr->store(bus_priv->bus, buf, count); |
1da177e4 LT |
115 | return ret; |
116 | } | |
117 | ||
118 | static struct sysfs_ops bus_sysfs_ops = { | |
119 | .show = bus_attr_show, | |
120 | .store = bus_attr_store, | |
121 | }; | |
122 | ||
4a3ad20c | 123 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
124 | { |
125 | int error; | |
5901d014 | 126 | if (bus_get(bus)) { |
c6f7e72a | 127 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 128 | bus_put(bus); |
1da177e4 LT |
129 | } else |
130 | error = -EINVAL; | |
131 | return error; | |
132 | } | |
4a3ad20c | 133 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 134 | |
4a3ad20c | 135 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 136 | { |
5901d014 | 137 | if (bus_get(bus)) { |
c6f7e72a | 138 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 139 | bus_put(bus); |
1da177e4 LT |
140 | } |
141 | } | |
4a3ad20c | 142 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 143 | |
80f03e34 | 144 | static struct kobj_type bus_ktype = { |
1da177e4 | 145 | .sysfs_ops = &bus_sysfs_ops, |
80f03e34 KS |
146 | }; |
147 | ||
148 | static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) | |
149 | { | |
150 | struct kobj_type *ktype = get_ktype(kobj); | |
151 | ||
152 | if (ktype == &bus_ktype) | |
153 | return 1; | |
154 | return 0; | |
155 | } | |
1da177e4 | 156 | |
80f03e34 KS |
157 | static struct kset_uevent_ops bus_uevent_ops = { |
158 | .filter = bus_uevent_filter, | |
1da177e4 LT |
159 | }; |
160 | ||
59a54833 | 161 | static struct kset *bus_kset; |
1da177e4 | 162 | |
1da177e4 | 163 | |
2139bdd5 | 164 | #ifdef CONFIG_HOTPLUG |
2b08c8d0 | 165 | /* Manually detach a device from its associated driver. */ |
151ef38f GKH |
166 | static ssize_t driver_unbind(struct device_driver *drv, |
167 | const char *buf, size_t count) | |
168 | { | |
5901d014 | 169 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
170 | struct device *dev; |
171 | int err = -ENODEV; | |
172 | ||
1f9ffc04 | 173 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 174 | if (dev && dev->driver == drv) { |
bf74ad5b AS |
175 | if (dev->parent) /* Needed for USB */ |
176 | down(&dev->parent->sem); | |
151ef38f | 177 | device_release_driver(dev); |
bf74ad5b AS |
178 | if (dev->parent) |
179 | up(&dev->parent->sem); | |
151ef38f GKH |
180 | err = count; |
181 | } | |
2b08c8d0 | 182 | put_device(dev); |
fc1ede58 | 183 | bus_put(bus); |
2b08c8d0 | 184 | return err; |
151ef38f GKH |
185 | } |
186 | static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind); | |
187 | ||
afdce75f GKH |
188 | /* |
189 | * Manually attach a device to a driver. | |
190 | * Note: the driver must want to bind to the device, | |
191 | * it is not possible to override the driver's id table. | |
192 | */ | |
193 | static ssize_t driver_bind(struct device_driver *drv, | |
194 | const char *buf, size_t count) | |
195 | { | |
5901d014 | 196 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
197 | struct device *dev; |
198 | int err = -ENODEV; | |
199 | ||
1f9ffc04 | 200 | dev = bus_find_device_by_name(bus, NULL, buf); |
49b420a1 | 201 | if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { |
bf74ad5b AS |
202 | if (dev->parent) /* Needed for USB */ |
203 | down(&dev->parent->sem); | |
afdce75f GKH |
204 | down(&dev->sem); |
205 | err = driver_probe_device(drv, dev); | |
206 | up(&dev->sem); | |
bf74ad5b AS |
207 | if (dev->parent) |
208 | up(&dev->parent->sem); | |
37225401 | 209 | |
4a3ad20c GKH |
210 | if (err > 0) { |
211 | /* success */ | |
37225401 | 212 | err = count; |
4a3ad20c GKH |
213 | } else if (err == 0) { |
214 | /* driver didn't accept device */ | |
37225401 | 215 | err = -ENODEV; |
4a3ad20c | 216 | } |
afdce75f | 217 | } |
2b08c8d0 | 218 | put_device(dev); |
fc1ede58 | 219 | bus_put(bus); |
2b08c8d0 | 220 | return err; |
afdce75f GKH |
221 | } |
222 | static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); | |
223 | ||
b8c5cec2 KS |
224 | static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) |
225 | { | |
c6f7e72a | 226 | return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
227 | } |
228 | ||
229 | static ssize_t store_drivers_autoprobe(struct bus_type *bus, | |
230 | const char *buf, size_t count) | |
231 | { | |
232 | if (buf[0] == '0') | |
c6f7e72a | 233 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 234 | else |
c6f7e72a | 235 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
236 | return count; |
237 | } | |
238 | ||
239 | static ssize_t store_drivers_probe(struct bus_type *bus, | |
240 | const char *buf, size_t count) | |
241 | { | |
242 | struct device *dev; | |
243 | ||
1f9ffc04 | 244 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
245 | if (!dev) |
246 | return -ENODEV; | |
247 | if (bus_rescan_devices_helper(dev, NULL) != 0) | |
248 | return -EINVAL; | |
249 | return count; | |
250 | } | |
2139bdd5 | 251 | #endif |
151ef38f | 252 | |
4a3ad20c | 253 | static struct device *next_device(struct klist_iter *i) |
465c7a3a | 254 | { |
4a3ad20c | 255 | struct klist_node *n = klist_next(i); |
ae1b4171 GKH |
256 | struct device *dev = NULL; |
257 | struct device_private *dev_prv; | |
258 | ||
259 | if (n) { | |
260 | dev_prv = to_device_private_bus(n); | |
261 | dev = dev_prv->device; | |
262 | } | |
263 | return dev; | |
465c7a3a | 264 | } |
265 | ||
1da177e4 | 266 | /** |
4a3ad20c GKH |
267 | * bus_for_each_dev - device iterator. |
268 | * @bus: bus type. | |
269 | * @start: device to start iterating from. | |
270 | * @data: data for the callback. | |
271 | * @fn: function to be called for each device. | |
1da177e4 | 272 | * |
4a3ad20c GKH |
273 | * Iterate over @bus's list of devices, and call @fn for each, |
274 | * passing it @data. If @start is not NULL, we use that device to | |
275 | * begin iterating from. | |
1da177e4 | 276 | * |
4a3ad20c GKH |
277 | * We check the return of @fn each time. If it returns anything |
278 | * other than 0, we break out and return that value. | |
1da177e4 | 279 | * |
4a3ad20c GKH |
280 | * NOTE: The device that returns a non-zero value is not retained |
281 | * in any way, nor is its refcount incremented. If the caller needs | |
0fa1b0a1 | 282 | * to retain this data, it should do so, and increment the reference |
4a3ad20c | 283 | * count in the supplied callback. |
1da177e4 | 284 | */ |
4a3ad20c GKH |
285 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
286 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 287 | { |
465c7a3a | 288 | struct klist_iter i; |
4a3ad20c | 289 | struct device *dev; |
465c7a3a | 290 | int error = 0; |
1da177e4 | 291 | |
465c7a3a | 292 | if (!bus) |
293 | return -EINVAL; | |
294 | ||
c6f7e72a | 295 | klist_iter_init_node(&bus->p->klist_devices, &i, |
ae1b4171 | 296 | (start ? &start->p->knode_bus : NULL)); |
465c7a3a | 297 | while ((dev = next_device(&i)) && !error) |
298 | error = fn(dev, data); | |
299 | klist_iter_exit(&i); | |
300 | return error; | |
1da177e4 | 301 | } |
4a3ad20c | 302 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 303 | |
0edb5860 CH |
304 | /** |
305 | * bus_find_device - device iterator for locating a particular device. | |
306 | * @bus: bus type | |
307 | * @start: Device to begin with | |
308 | * @data: Data to pass to match function | |
309 | * @match: Callback function to check device | |
310 | * | |
311 | * This is similar to the bus_for_each_dev() function above, but it | |
312 | * returns a reference to a device that is 'found' for later use, as | |
313 | * determined by the @match callback. | |
314 | * | |
315 | * The callback should return 0 if the device doesn't match and non-zero | |
316 | * if it does. If the callback returns non-zero, this function will | |
317 | * return to the caller and not iterate over any more devices. | |
318 | */ | |
4a3ad20c GKH |
319 | struct device *bus_find_device(struct bus_type *bus, |
320 | struct device *start, void *data, | |
321 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
322 | { |
323 | struct klist_iter i; | |
324 | struct device *dev; | |
325 | ||
326 | if (!bus) | |
327 | return NULL; | |
328 | ||
c6f7e72a | 329 | klist_iter_init_node(&bus->p->klist_devices, &i, |
ae1b4171 | 330 | (start ? &start->p->knode_bus : NULL)); |
0edb5860 CH |
331 | while ((dev = next_device(&i))) |
332 | if (match(dev, data) && get_device(dev)) | |
333 | break; | |
334 | klist_iter_exit(&i); | |
335 | return dev; | |
336 | } | |
4a3ad20c | 337 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 338 | |
1f9ffc04 GKH |
339 | static int match_name(struct device *dev, void *data) |
340 | { | |
341 | const char *name = data; | |
342 | ||
1e0b2cf9 | 343 | return sysfs_streq(name, dev_name(dev)); |
1f9ffc04 GKH |
344 | } |
345 | ||
346 | /** | |
347 | * bus_find_device_by_name - device iterator for locating a particular device of a specific name | |
348 | * @bus: bus type | |
349 | * @start: Device to begin with | |
350 | * @name: name of the device to match | |
351 | * | |
352 | * This is similar to the bus_find_device() function above, but it handles | |
353 | * searching by a name automatically, no need to write another strcmp matching | |
354 | * function. | |
355 | */ | |
356 | struct device *bus_find_device_by_name(struct bus_type *bus, | |
357 | struct device *start, const char *name) | |
358 | { | |
359 | return bus_find_device(bus, start, (void *)name, match_name); | |
360 | } | |
361 | EXPORT_SYMBOL_GPL(bus_find_device_by_name); | |
362 | ||
4a3ad20c | 363 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 364 | { |
4a3ad20c | 365 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
366 | struct driver_private *drv_priv; |
367 | ||
368 | if (n) { | |
369 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
370 | return drv_priv->driver; | |
371 | } | |
372 | return NULL; | |
38fdac3c | 373 | } |
374 | ||
1da177e4 | 375 | /** |
4a3ad20c GKH |
376 | * bus_for_each_drv - driver iterator |
377 | * @bus: bus we're dealing with. | |
378 | * @start: driver to start iterating on. | |
379 | * @data: data to pass to the callback. | |
380 | * @fn: function to call for each driver. | |
1da177e4 | 381 | * |
4a3ad20c GKH |
382 | * This is nearly identical to the device iterator above. |
383 | * We iterate over each driver that belongs to @bus, and call | |
384 | * @fn for each. If @fn returns anything but 0, we break out | |
385 | * and return it. If @start is not NULL, we use it as the head | |
386 | * of the list. | |
1da177e4 | 387 | * |
4a3ad20c GKH |
388 | * NOTE: we don't return the driver that returns a non-zero |
389 | * value, nor do we leave the reference count incremented for that | |
390 | * driver. If the caller needs to know that info, it must set it | |
391 | * in the callback. It must also be sure to increment the refcount | |
392 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 393 | */ |
4a3ad20c GKH |
394 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
395 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 396 | { |
38fdac3c | 397 | struct klist_iter i; |
4a3ad20c | 398 | struct device_driver *drv; |
38fdac3c | 399 | int error = 0; |
1da177e4 | 400 | |
38fdac3c | 401 | if (!bus) |
402 | return -EINVAL; | |
403 | ||
c6f7e72a | 404 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
e5dd1278 | 405 | start ? &start->p->knode_bus : NULL); |
38fdac3c | 406 | while ((drv = next_driver(&i)) && !error) |
407 | error = fn(drv, data); | |
408 | klist_iter_exit(&i); | |
409 | return error; | |
1da177e4 | 410 | } |
4a3ad20c | 411 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 412 | |
4aca67e5 | 413 | static int device_add_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
414 | { |
415 | int error = 0; | |
416 | int i; | |
417 | ||
4aca67e5 AM |
418 | if (!bus->dev_attrs) |
419 | return 0; | |
420 | ||
421 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) { | |
4a3ad20c | 422 | error = device_create_file(dev, &bus->dev_attrs[i]); |
4aca67e5 AM |
423 | if (error) { |
424 | while (--i >= 0) | |
425 | device_remove_file(dev, &bus->dev_attrs[i]); | |
426 | break; | |
1da177e4 LT |
427 | } |
428 | } | |
1da177e4 | 429 | return error; |
1da177e4 LT |
430 | } |
431 | ||
4a3ad20c | 432 | static void device_remove_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
433 | { |
434 | int i; | |
435 | ||
436 | if (bus->dev_attrs) { | |
437 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) | |
4a3ad20c | 438 | device_remove_file(dev, &bus->dev_attrs[i]); |
1da177e4 LT |
439 | } |
440 | } | |
441 | ||
b9cafc7d KS |
442 | #ifdef CONFIG_SYSFS_DEPRECATED |
443 | static int make_deprecated_bus_links(struct device *dev) | |
444 | { | |
445 | return sysfs_create_link(&dev->kobj, | |
c6f7e72a | 446 | &dev->bus->p->subsys.kobj, "bus"); |
b9cafc7d KS |
447 | } |
448 | ||
449 | static void remove_deprecated_bus_links(struct device *dev) | |
450 | { | |
451 | sysfs_remove_link(&dev->kobj, "bus"); | |
452 | } | |
453 | #else | |
454 | static inline int make_deprecated_bus_links(struct device *dev) { return 0; } | |
455 | static inline void remove_deprecated_bus_links(struct device *dev) { } | |
456 | #endif | |
1da177e4 LT |
457 | |
458 | /** | |
4a3ad20c GKH |
459 | * bus_add_device - add device to bus |
460 | * @dev: device being added | |
1da177e4 | 461 | * |
2023c610 AS |
462 | * - Add device's bus attributes. |
463 | * - Create links to device's bus. | |
4a3ad20c | 464 | * - Add the device to its bus's list of devices. |
1da177e4 | 465 | */ |
4a3ad20c | 466 | int bus_add_device(struct device *dev) |
1da177e4 | 467 | { |
4a3ad20c | 468 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
469 | int error = 0; |
470 | ||
471 | if (bus) { | |
1e0b2cf9 | 472 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
d377e85b | 473 | error = device_add_attrs(bus, dev); |
f86db396 | 474 | if (error) |
513e7337 | 475 | goto out_put; |
c6f7e72a | 476 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 477 | &dev->kobj, dev_name(dev)); |
f86db396 | 478 | if (error) |
513e7337 | 479 | goto out_id; |
f86db396 | 480 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 481 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 482 | if (error) |
513e7337 | 483 | goto out_subsys; |
b9cafc7d | 484 | error = make_deprecated_bus_links(dev); |
513e7337 CH |
485 | if (error) |
486 | goto out_deprecated; | |
2023c610 | 487 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 488 | } |
513e7337 CH |
489 | return 0; |
490 | ||
491 | out_deprecated: | |
492 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
493 | out_subsys: | |
1e0b2cf9 | 494 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
513e7337 CH |
495 | out_id: |
496 | device_remove_attrs(bus, dev); | |
497 | out_put: | |
fc1ede58 | 498 | bus_put(dev->bus); |
1da177e4 LT |
499 | return error; |
500 | } | |
501 | ||
53877d06 | 502 | /** |
2023c610 AS |
503 | * bus_probe_device - probe drivers for a new device |
504 | * @dev: device to probe | |
53877d06 | 505 | * |
2023c610 | 506 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 507 | */ |
2023c610 | 508 | void bus_probe_device(struct device *dev) |
53877d06 | 509 | { |
f86db396 | 510 | struct bus_type *bus = dev->bus; |
2023c610 | 511 | int ret; |
53877d06 | 512 | |
2023c610 AS |
513 | if (bus && bus->p->drivers_autoprobe) { |
514 | ret = device_attach(dev); | |
c6a46696 | 515 | WARN_ON(ret < 0); |
53877d06 KS |
516 | } |
517 | } | |
518 | ||
1da177e4 | 519 | /** |
4a3ad20c GKH |
520 | * bus_remove_device - remove device from bus |
521 | * @dev: device to be removed | |
1da177e4 | 522 | * |
4a3ad20c GKH |
523 | * - Remove symlink from bus's directory. |
524 | * - Delete device from bus's list. | |
525 | * - Detach from its driver. | |
526 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 527 | */ |
4a3ad20c | 528 | void bus_remove_device(struct device *dev) |
1da177e4 LT |
529 | { |
530 | if (dev->bus) { | |
b9d9c82b | 531 | sysfs_remove_link(&dev->kobj, "subsystem"); |
b9cafc7d | 532 | remove_deprecated_bus_links(dev); |
4a3ad20c | 533 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, |
1e0b2cf9 | 534 | dev_name(dev)); |
1da177e4 | 535 | device_remove_attrs(dev->bus, dev); |
ae1b4171 GKH |
536 | if (klist_node_attached(&dev->p->knode_bus)) |
537 | klist_del(&dev->p->knode_bus); | |
3f62e570 | 538 | |
4a3ad20c | 539 | pr_debug("bus: '%s': remove device %s\n", |
1e0b2cf9 | 540 | dev->bus->name, dev_name(dev)); |
1da177e4 | 541 | device_release_driver(dev); |
fc1ede58 | 542 | bus_put(dev->bus); |
1da177e4 LT |
543 | } |
544 | } | |
545 | ||
4a3ad20c | 546 | static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv) |
1da177e4 LT |
547 | { |
548 | int error = 0; | |
549 | int i; | |
550 | ||
551 | if (bus->drv_attrs) { | |
552 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) { | |
553 | error = driver_create_file(drv, &bus->drv_attrs[i]); | |
554 | if (error) | |
4a3ad20c | 555 | goto err; |
1da177e4 LT |
556 | } |
557 | } | |
4a3ad20c | 558 | done: |
1da177e4 | 559 | return error; |
4a3ad20c | 560 | err: |
1da177e4 LT |
561 | while (--i >= 0) |
562 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
4a3ad20c | 563 | goto done; |
1da177e4 LT |
564 | } |
565 | ||
4a3ad20c GKH |
566 | static void driver_remove_attrs(struct bus_type *bus, |
567 | struct device_driver *drv) | |
1da177e4 LT |
568 | { |
569 | int i; | |
570 | ||
571 | if (bus->drv_attrs) { | |
572 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) | |
573 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
574 | } | |
575 | } | |
576 | ||
874c6241 GKH |
577 | #ifdef CONFIG_HOTPLUG |
578 | /* | |
579 | * Thanks to drivers making their tables __devinit, we can't allow manual | |
580 | * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. | |
581 | */ | |
f86db396 | 582 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 583 | { |
f86db396 AM |
584 | int ret; |
585 | ||
586 | ret = driver_create_file(drv, &driver_attr_unbind); | |
587 | if (ret == 0) { | |
588 | ret = driver_create_file(drv, &driver_attr_bind); | |
589 | if (ret) | |
590 | driver_remove_file(drv, &driver_attr_unbind); | |
591 | } | |
592 | return ret; | |
874c6241 GKH |
593 | } |
594 | ||
595 | static void remove_bind_files(struct device_driver *drv) | |
596 | { | |
597 | driver_remove_file(drv, &driver_attr_bind); | |
598 | driver_remove_file(drv, &driver_attr_unbind); | |
599 | } | |
b8c5cec2 | 600 | |
8380770c KS |
601 | static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); |
602 | static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, | |
603 | show_drivers_autoprobe, store_drivers_autoprobe); | |
604 | ||
b8c5cec2 KS |
605 | static int add_probe_files(struct bus_type *bus) |
606 | { | |
607 | int retval; | |
608 | ||
8380770c | 609 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
610 | if (retval) |
611 | goto out; | |
612 | ||
8380770c | 613 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 614 | if (retval) |
8380770c | 615 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
616 | out: |
617 | return retval; | |
618 | } | |
619 | ||
620 | static void remove_probe_files(struct bus_type *bus) | |
621 | { | |
8380770c KS |
622 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
623 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 624 | } |
874c6241 | 625 | #else |
35acfdd7 | 626 | static inline int add_bind_files(struct device_driver *drv) { return 0; } |
874c6241 | 627 | static inline void remove_bind_files(struct device_driver *drv) {} |
b8c5cec2 KS |
628 | static inline int add_probe_files(struct bus_type *bus) { return 0; } |
629 | static inline void remove_probe_files(struct bus_type *bus) {} | |
874c6241 | 630 | #endif |
1da177e4 | 631 | |
7ac1cf4a KS |
632 | static ssize_t driver_uevent_store(struct device_driver *drv, |
633 | const char *buf, size_t count) | |
634 | { | |
635 | enum kobject_action action; | |
636 | ||
637 | if (kobject_action_type(buf, count, &action) == 0) | |
e5dd1278 | 638 | kobject_uevent(&drv->p->kobj, action); |
7ac1cf4a KS |
639 | return count; |
640 | } | |
641 | static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store); | |
642 | ||
1da177e4 | 643 | /** |
4a3ad20c GKH |
644 | * bus_add_driver - Add a driver to the bus. |
645 | * @drv: driver. | |
1da177e4 | 646 | */ |
f86db396 | 647 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 648 | { |
e5dd1278 GKH |
649 | struct bus_type *bus; |
650 | struct driver_private *priv; | |
1da177e4 LT |
651 | int error = 0; |
652 | ||
e5dd1278 | 653 | bus = bus_get(drv->bus); |
d9fd4d3b | 654 | if (!bus) |
4f6e1945 | 655 | return -EINVAL; |
d9fd4d3b | 656 | |
7dc72b28 | 657 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
658 | |
659 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
660 | if (!priv) { |
661 | error = -ENOMEM; | |
662 | goto out_put_bus; | |
663 | } | |
e5dd1278 GKH |
664 | klist_init(&priv->klist_devices, NULL, NULL); |
665 | priv->driver = drv; | |
666 | drv->p = priv; | |
c8e90d82 GKH |
667 | priv->kobj.kset = bus->p->drivers_kset; |
668 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
669 | "%s", drv->name); | |
dc0afa83 | 670 | if (error) |
07634464 | 671 | goto out_unregister; |
d9fd4d3b | 672 | |
c6f7e72a | 673 | if (drv->bus->p->drivers_autoprobe) { |
b8c5cec2 KS |
674 | error = driver_attach(drv); |
675 | if (error) | |
676 | goto out_unregister; | |
677 | } | |
e5dd1278 | 678 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
d9fd4d3b JG |
679 | module_add_driver(drv->owner, drv); |
680 | ||
7ac1cf4a KS |
681 | error = driver_create_file(drv, &driver_attr_uevent); |
682 | if (error) { | |
683 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 684 | __func__, drv->name); |
7ac1cf4a | 685 | } |
d9fd4d3b JG |
686 | error = driver_add_attrs(bus, drv); |
687 | if (error) { | |
688 | /* How the hell do we get out of this pickle? Give up */ | |
689 | printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", | |
2b3a302a | 690 | __func__, drv->name); |
d9fd4d3b JG |
691 | } |
692 | error = add_bind_files(drv); | |
693 | if (error) { | |
694 | /* Ditto */ | |
695 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
2b3a302a | 696 | __func__, drv->name); |
1da177e4 | 697 | } |
d9fd4d3b | 698 | |
c8e90d82 | 699 | kobject_uevent(&priv->kobj, KOBJ_ADD); |
5c8563d7 | 700 | return 0; |
f86db396 | 701 | out_unregister: |
5c8563d7 KS |
702 | kfree(drv->p); |
703 | drv->p = NULL; | |
c10997f6 | 704 | kobject_put(&priv->kobj); |
f86db396 | 705 | out_put_bus: |
fc1ede58 | 706 | bus_put(bus); |
f86db396 | 707 | return error; |
1da177e4 LT |
708 | } |
709 | ||
1da177e4 | 710 | /** |
4a3ad20c GKH |
711 | * bus_remove_driver - delete driver from bus's knowledge. |
712 | * @drv: driver. | |
1da177e4 | 713 | * |
4a3ad20c GKH |
714 | * Detach the driver from the devices it controls, and remove |
715 | * it from its bus's list of drivers. Finally, we drop the reference | |
716 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 717 | */ |
4a3ad20c | 718 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 719 | { |
d9fd4d3b JG |
720 | if (!drv->bus) |
721 | return; | |
722 | ||
723 | remove_bind_files(drv); | |
724 | driver_remove_attrs(drv->bus, drv); | |
7ac1cf4a | 725 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 726 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 727 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
728 | driver_detach(drv); |
729 | module_remove_driver(drv); | |
c10997f6 | 730 | kobject_put(&drv->p->kobj); |
fc1ede58 | 731 | bus_put(drv->bus); |
1da177e4 LT |
732 | } |
733 | ||
1da177e4 | 734 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 735 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 736 | void *data) |
1da177e4 | 737 | { |
f86db396 AM |
738 | int ret = 0; |
739 | ||
bf74ad5b AS |
740 | if (!dev->driver) { |
741 | if (dev->parent) /* Needed for USB */ | |
742 | down(&dev->parent->sem); | |
f86db396 | 743 | ret = device_attach(dev); |
bf74ad5b AS |
744 | if (dev->parent) |
745 | up(&dev->parent->sem); | |
746 | } | |
f86db396 | 747 | return ret < 0 ? ret : 0; |
1da177e4 LT |
748 | } |
749 | ||
1da177e4 | 750 | /** |
23d3d602 GKH |
751 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
752 | * @bus: the bus to scan. | |
1da177e4 | 753 | * |
23d3d602 GKH |
754 | * This function will look for devices on the bus with no driver |
755 | * attached and rescan it against existing drivers to see if it matches | |
756 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 757 | */ |
4a3ad20c | 758 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 759 | { |
f86db396 | 760 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 761 | } |
4a3ad20c | 762 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 763 | |
e935d5da ME |
764 | /** |
765 | * device_reprobe - remove driver for a device and probe for a new driver | |
766 | * @dev: the device to reprobe | |
767 | * | |
768 | * This function detaches the attached driver (if any) for the given | |
769 | * device and restarts the driver probing process. It is intended | |
770 | * to use if probing criteria changed during a devices lifetime and | |
771 | * driver attachment should change accordingly. | |
772 | */ | |
f86db396 | 773 | int device_reprobe(struct device *dev) |
e935d5da ME |
774 | { |
775 | if (dev->driver) { | |
776 | if (dev->parent) /* Needed for USB */ | |
777 | down(&dev->parent->sem); | |
778 | device_release_driver(dev); | |
779 | if (dev->parent) | |
780 | up(&dev->parent->sem); | |
781 | } | |
f86db396 | 782 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
783 | } |
784 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 785 | |
1da177e4 | 786 | /** |
4a3ad20c GKH |
787 | * find_bus - locate bus by name. |
788 | * @name: name of bus. | |
1da177e4 | 789 | * |
4a3ad20c GKH |
790 | * Call kset_find_obj() to iterate over list of buses to |
791 | * find a bus by name. Return bus if found. | |
1da177e4 | 792 | * |
4a3ad20c | 793 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 794 | */ |
7e4ef085 | 795 | #if 0 |
4a3ad20c | 796 | struct bus_type *find_bus(char *name) |
1da177e4 | 797 | { |
4a3ad20c | 798 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
799 | return k ? to_bus(k) : NULL; |
800 | } | |
7e4ef085 | 801 | #endif /* 0 */ |
1da177e4 LT |
802 | |
803 | ||
804 | /** | |
4a3ad20c GKH |
805 | * bus_add_attrs - Add default attributes for this bus. |
806 | * @bus: Bus that has just been registered. | |
1da177e4 LT |
807 | */ |
808 | ||
4a3ad20c | 809 | static int bus_add_attrs(struct bus_type *bus) |
1da177e4 LT |
810 | { |
811 | int error = 0; | |
812 | int i; | |
813 | ||
814 | if (bus->bus_attrs) { | |
815 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) { | |
4a3ad20c | 816 | error = bus_create_file(bus, &bus->bus_attrs[i]); |
dc0afa83 | 817 | if (error) |
4a3ad20c | 818 | goto err; |
1da177e4 LT |
819 | } |
820 | } | |
4a3ad20c | 821 | done: |
1da177e4 | 822 | return error; |
4a3ad20c | 823 | err: |
1da177e4 | 824 | while (--i >= 0) |
4a3ad20c GKH |
825 | bus_remove_file(bus, &bus->bus_attrs[i]); |
826 | goto done; | |
1da177e4 LT |
827 | } |
828 | ||
4a3ad20c | 829 | static void bus_remove_attrs(struct bus_type *bus) |
1da177e4 LT |
830 | { |
831 | int i; | |
832 | ||
833 | if (bus->bus_attrs) { | |
834 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) | |
4a3ad20c | 835 | bus_remove_file(bus, &bus->bus_attrs[i]); |
1da177e4 LT |
836 | } |
837 | } | |
838 | ||
34bb61f9 JB |
839 | static void klist_devices_get(struct klist_node *n) |
840 | { | |
ae1b4171 GKH |
841 | struct device_private *dev_prv = to_device_private_bus(n); |
842 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
843 | |
844 | get_device(dev); | |
845 | } | |
846 | ||
847 | static void klist_devices_put(struct klist_node *n) | |
848 | { | |
ae1b4171 GKH |
849 | struct device_private *dev_prv = to_device_private_bus(n); |
850 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
851 | |
852 | put_device(dev); | |
853 | } | |
854 | ||
7ac1cf4a KS |
855 | static ssize_t bus_uevent_store(struct bus_type *bus, |
856 | const char *buf, size_t count) | |
857 | { | |
858 | enum kobject_action action; | |
859 | ||
860 | if (kobject_action_type(buf, count, &action) == 0) | |
c6f7e72a | 861 | kobject_uevent(&bus->p->subsys.kobj, action); |
7ac1cf4a KS |
862 | return count; |
863 | } | |
864 | static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); | |
865 | ||
1da177e4 | 866 | /** |
4a3ad20c GKH |
867 | * bus_register - register a bus with the system. |
868 | * @bus: bus. | |
1da177e4 | 869 | * |
4a3ad20c GKH |
870 | * Once we have that, we registered the bus with the kobject |
871 | * infrastructure, then register the children subsystems it has: | |
872 | * the devices and drivers that belong to the bus. | |
1da177e4 | 873 | */ |
4a3ad20c | 874 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
875 | { |
876 | int retval; | |
c6f7e72a GKH |
877 | struct bus_type_private *priv; |
878 | ||
879 | priv = kzalloc(sizeof(struct bus_type_private), GFP_KERNEL); | |
880 | if (!priv) | |
881 | return -ENOMEM; | |
882 | ||
883 | priv->bus = bus; | |
884 | bus->p = priv; | |
1da177e4 | 885 | |
c6f7e72a | 886 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 887 | |
c6f7e72a | 888 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
889 | if (retval) |
890 | goto out; | |
891 | ||
c6f7e72a GKH |
892 | priv->subsys.kobj.kset = bus_kset; |
893 | priv->subsys.kobj.ktype = &bus_ktype; | |
894 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 895 | |
c6f7e72a | 896 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
897 | if (retval) |
898 | goto out; | |
899 | ||
7ac1cf4a KS |
900 | retval = bus_create_file(bus, &bus_attr_uevent); |
901 | if (retval) | |
902 | goto bus_uevent_fail; | |
903 | ||
c6f7e72a GKH |
904 | priv->devices_kset = kset_create_and_add("devices", NULL, |
905 | &priv->subsys.kobj); | |
906 | if (!priv->devices_kset) { | |
3d899596 | 907 | retval = -ENOMEM; |
1da177e4 | 908 | goto bus_devices_fail; |
3d899596 | 909 | } |
1da177e4 | 910 | |
c6f7e72a GKH |
911 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
912 | &priv->subsys.kobj); | |
913 | if (!priv->drivers_kset) { | |
6dcec251 | 914 | retval = -ENOMEM; |
1da177e4 | 915 | goto bus_drivers_fail; |
6dcec251 | 916 | } |
465c7a3a | 917 | |
c6f7e72a GKH |
918 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
919 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 920 | |
b8c5cec2 KS |
921 | retval = add_probe_files(bus); |
922 | if (retval) | |
923 | goto bus_probe_files_fail; | |
924 | ||
1bb6881a CH |
925 | retval = bus_add_attrs(bus); |
926 | if (retval) | |
927 | goto bus_attrs_fail; | |
1da177e4 | 928 | |
7dc72b28 | 929 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
930 | return 0; |
931 | ||
1bb6881a | 932 | bus_attrs_fail: |
b8c5cec2 KS |
933 | remove_probe_files(bus); |
934 | bus_probe_files_fail: | |
c6f7e72a | 935 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 936 | bus_drivers_fail: |
c6f7e72a | 937 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 938 | bus_devices_fail: |
7ac1cf4a KS |
939 | bus_remove_file(bus, &bus_attr_uevent); |
940 | bus_uevent_fail: | |
c6f7e72a GKH |
941 | kset_unregister(&bus->p->subsys); |
942 | kfree(bus->p); | |
1da177e4 | 943 | out: |
f48f3feb | 944 | bus->p = NULL; |
1da177e4 LT |
945 | return retval; |
946 | } | |
4a3ad20c | 947 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 948 | |
1da177e4 | 949 | /** |
4a3ad20c GKH |
950 | * bus_unregister - remove a bus from the system |
951 | * @bus: bus. | |
1da177e4 | 952 | * |
4a3ad20c GKH |
953 | * Unregister the child subsystems and the bus itself. |
954 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 955 | */ |
4a3ad20c | 956 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 957 | { |
7dc72b28 | 958 | pr_debug("bus: '%s': unregistering\n", bus->name); |
1da177e4 | 959 | bus_remove_attrs(bus); |
b8c5cec2 | 960 | remove_probe_files(bus); |
c6f7e72a GKH |
961 | kset_unregister(bus->p->drivers_kset); |
962 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 963 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a GKH |
964 | kset_unregister(&bus->p->subsys); |
965 | kfree(bus->p); | |
f48f3feb | 966 | bus->p = NULL; |
1da177e4 | 967 | } |
4a3ad20c | 968 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 969 | |
116af378 BH |
970 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
971 | { | |
c6f7e72a | 972 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
973 | } |
974 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
975 | ||
976 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
977 | { | |
c6f7e72a | 978 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
979 | } |
980 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
981 | ||
0fed80f7 GKH |
982 | struct kset *bus_get_kset(struct bus_type *bus) |
983 | { | |
c6f7e72a | 984 | return &bus->p->subsys; |
0fed80f7 GKH |
985 | } |
986 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
987 | ||
b249072e GKH |
988 | struct klist *bus_get_device_klist(struct bus_type *bus) |
989 | { | |
c6f7e72a | 990 | return &bus->p->klist_devices; |
b249072e GKH |
991 | } |
992 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
993 | ||
99178b03 GKH |
994 | /* |
995 | * Yes, this forcably breaks the klist abstraction temporarily. It | |
996 | * just wants to sort the klist, not change reference counts and | |
997 | * take/drop locks rapidly in the process. It does all this while | |
998 | * holding the lock for the list, so objects can't otherwise be | |
999 | * added/removed while we're swizzling. | |
1000 | */ | |
1001 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
1002 | int (*compare)(const struct device *a, | |
1003 | const struct device *b)) | |
1004 | { | |
1005 | struct list_head *pos; | |
1006 | struct klist_node *n; | |
ae1b4171 | 1007 | struct device_private *dev_prv; |
99178b03 GKH |
1008 | struct device *b; |
1009 | ||
1010 | list_for_each(pos, list) { | |
1011 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1012 | dev_prv = to_device_private_bus(n); |
1013 | b = dev_prv->device; | |
99178b03 | 1014 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
1015 | list_move_tail(&a->p->knode_bus.n_node, |
1016 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
1017 | return; |
1018 | } | |
1019 | } | |
ae1b4171 | 1020 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
1021 | } |
1022 | ||
1023 | void bus_sort_breadthfirst(struct bus_type *bus, | |
1024 | int (*compare)(const struct device *a, | |
1025 | const struct device *b)) | |
1026 | { | |
1027 | LIST_HEAD(sorted_devices); | |
1028 | struct list_head *pos, *tmp; | |
1029 | struct klist_node *n; | |
ae1b4171 | 1030 | struct device_private *dev_prv; |
99178b03 GKH |
1031 | struct device *dev; |
1032 | struct klist *device_klist; | |
1033 | ||
1034 | device_klist = bus_get_device_klist(bus); | |
1035 | ||
1036 | spin_lock(&device_klist->k_lock); | |
1037 | list_for_each_safe(pos, tmp, &device_klist->k_list) { | |
1038 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1039 | dev_prv = to_device_private_bus(n); |
1040 | dev = dev_prv->device; | |
99178b03 GKH |
1041 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
1042 | } | |
1043 | list_splice(&sorted_devices, &device_klist->k_list); | |
1044 | spin_unlock(&device_klist->k_lock); | |
1045 | } | |
1046 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
1047 | ||
1da177e4 LT |
1048 | int __init buses_init(void) |
1049 | { | |
59a54833 GKH |
1050 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1051 | if (!bus_kset) | |
1052 | return -ENOMEM; | |
1053 | return 0; | |
1da177e4 | 1054 | } |