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> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
1da177e4 LT |
17 | #include <linux/init.h> |
18 | #include <linux/string.h> | |
19 | #include "base.h" | |
20 | #include "power/power.h" | |
21 | ||
1da177e4 | 22 | #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) |
c6f7e72a | 23 | #define to_bus(obj) container_of(obj, struct bus_type_private, subsys.kobj) |
1da177e4 LT |
24 | |
25 | /* | |
26 | * sysfs bindings for drivers | |
27 | */ | |
28 | ||
29 | #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) | |
1da177e4 LT |
30 | |
31 | ||
b8c5cec2 KS |
32 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
33 | void *data); | |
34 | ||
5901d014 GKH |
35 | static struct bus_type *bus_get(struct bus_type *bus) |
36 | { | |
c6f7e72a GKH |
37 | if (bus) { |
38 | kset_get(&bus->p->subsys); | |
39 | return bus; | |
40 | } | |
41 | return NULL; | |
5901d014 GKH |
42 | } |
43 | ||
fc1ede58 GKH |
44 | static void bus_put(struct bus_type *bus) |
45 | { | |
c6f7e72a GKH |
46 | if (bus) |
47 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
48 | } |
49 | ||
4a3ad20c GKH |
50 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
51 | char *buf) | |
1da177e4 | 52 | { |
4a3ad20c | 53 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 54 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 55 | ssize_t ret = -EIO; |
1da177e4 LT |
56 | |
57 | if (drv_attr->show) | |
e5dd1278 | 58 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
59 | return ret; |
60 | } | |
61 | ||
4a3ad20c GKH |
62 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
63 | const char *buf, size_t count) | |
1da177e4 | 64 | { |
4a3ad20c | 65 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 66 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 67 | ssize_t ret = -EIO; |
1da177e4 LT |
68 | |
69 | if (drv_attr->store) | |
e5dd1278 | 70 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
71 | return ret; |
72 | } | |
73 | ||
52cf25d0 | 74 | static const struct sysfs_ops driver_sysfs_ops = { |
1da177e4 LT |
75 | .show = drv_attr_show, |
76 | .store = drv_attr_store, | |
77 | }; | |
78 | ||
e5dd1278 | 79 | static void driver_release(struct kobject *kobj) |
1da177e4 | 80 | { |
e5dd1278 GKH |
81 | struct driver_private *drv_priv = to_driver(kobj); |
82 | ||
2b3a302a | 83 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 84 | kfree(drv_priv); |
1da177e4 LT |
85 | } |
86 | ||
a1148fb0 | 87 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
88 | .sysfs_ops = &driver_sysfs_ops, |
89 | .release = driver_release, | |
90 | }; | |
91 | ||
1da177e4 LT |
92 | /* |
93 | * sysfs bindings for buses | |
94 | */ | |
4a3ad20c GKH |
95 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
96 | char *buf) | |
1da177e4 | 97 | { |
4a3ad20c | 98 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
c6f7e72a | 99 | struct bus_type_private *bus_priv = to_bus(kobj); |
1da177e4 LT |
100 | ssize_t ret = 0; |
101 | ||
102 | if (bus_attr->show) | |
c6f7e72a | 103 | ret = bus_attr->show(bus_priv->bus, buf); |
1da177e4 LT |
104 | return ret; |
105 | } | |
106 | ||
4a3ad20c GKH |
107 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
108 | const char *buf, size_t count) | |
1da177e4 | 109 | { |
4a3ad20c | 110 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
c6f7e72a | 111 | struct bus_type_private *bus_priv = to_bus(kobj); |
1da177e4 LT |
112 | ssize_t ret = 0; |
113 | ||
114 | if (bus_attr->store) | |
c6f7e72a | 115 | ret = bus_attr->store(bus_priv->bus, buf, count); |
1da177e4 LT |
116 | return ret; |
117 | } | |
118 | ||
52cf25d0 | 119 | static const struct sysfs_ops bus_sysfs_ops = { |
1da177e4 LT |
120 | .show = bus_attr_show, |
121 | .store = bus_attr_store, | |
122 | }; | |
123 | ||
4a3ad20c | 124 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
125 | { |
126 | int error; | |
5901d014 | 127 | if (bus_get(bus)) { |
c6f7e72a | 128 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 129 | bus_put(bus); |
1da177e4 LT |
130 | } else |
131 | error = -EINVAL; | |
132 | return error; | |
133 | } | |
4a3ad20c | 134 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 135 | |
4a3ad20c | 136 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 137 | { |
5901d014 | 138 | if (bus_get(bus)) { |
c6f7e72a | 139 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 140 | bus_put(bus); |
1da177e4 LT |
141 | } |
142 | } | |
4a3ad20c | 143 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 144 | |
80f03e34 | 145 | static struct kobj_type bus_ktype = { |
1da177e4 | 146 | .sysfs_ops = &bus_sysfs_ops, |
80f03e34 KS |
147 | }; |
148 | ||
149 | static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) | |
150 | { | |
151 | struct kobj_type *ktype = get_ktype(kobj); | |
152 | ||
153 | if (ktype == &bus_ktype) | |
154 | return 1; | |
155 | return 0; | |
156 | } | |
1da177e4 | 157 | |
9cd43611 | 158 | static const struct kset_uevent_ops bus_uevent_ops = { |
80f03e34 | 159 | .filter = bus_uevent_filter, |
1da177e4 LT |
160 | }; |
161 | ||
59a54833 | 162 | static struct kset *bus_kset; |
1da177e4 | 163 | |
1da177e4 | 164 | |
2139bdd5 | 165 | #ifdef CONFIG_HOTPLUG |
2b08c8d0 | 166 | /* Manually detach a device from its associated driver. */ |
151ef38f GKH |
167 | static ssize_t driver_unbind(struct device_driver *drv, |
168 | const char *buf, size_t count) | |
169 | { | |
5901d014 | 170 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
171 | struct device *dev; |
172 | int err = -ENODEV; | |
173 | ||
1f9ffc04 | 174 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 175 | if (dev && dev->driver == drv) { |
bf74ad5b | 176 | if (dev->parent) /* Needed for USB */ |
8e9394ce | 177 | device_lock(dev->parent); |
151ef38f | 178 | device_release_driver(dev); |
bf74ad5b | 179 | if (dev->parent) |
8e9394ce | 180 | device_unlock(dev->parent); |
151ef38f GKH |
181 | err = count; |
182 | } | |
2b08c8d0 | 183 | put_device(dev); |
fc1ede58 | 184 | bus_put(bus); |
2b08c8d0 | 185 | return err; |
151ef38f GKH |
186 | } |
187 | static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind); | |
188 | ||
afdce75f GKH |
189 | /* |
190 | * Manually attach a device to a driver. | |
191 | * Note: the driver must want to bind to the device, | |
192 | * it is not possible to override the driver's id table. | |
193 | */ | |
194 | static ssize_t driver_bind(struct device_driver *drv, | |
195 | const char *buf, size_t count) | |
196 | { | |
5901d014 | 197 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
198 | struct device *dev; |
199 | int err = -ENODEV; | |
200 | ||
1f9ffc04 | 201 | dev = bus_find_device_by_name(bus, NULL, buf); |
49b420a1 | 202 | if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { |
bf74ad5b | 203 | if (dev->parent) /* Needed for USB */ |
8e9394ce GKH |
204 | device_lock(dev->parent); |
205 | device_lock(dev); | |
afdce75f | 206 | err = driver_probe_device(drv, dev); |
8e9394ce | 207 | device_unlock(dev); |
bf74ad5b | 208 | if (dev->parent) |
8e9394ce | 209 | device_unlock(dev->parent); |
37225401 | 210 | |
4a3ad20c GKH |
211 | if (err > 0) { |
212 | /* success */ | |
37225401 | 213 | err = count; |
4a3ad20c GKH |
214 | } else if (err == 0) { |
215 | /* driver didn't accept device */ | |
37225401 | 216 | err = -ENODEV; |
4a3ad20c | 217 | } |
afdce75f | 218 | } |
2b08c8d0 | 219 | put_device(dev); |
fc1ede58 | 220 | bus_put(bus); |
2b08c8d0 | 221 | return err; |
afdce75f GKH |
222 | } |
223 | static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); | |
224 | ||
b8c5cec2 KS |
225 | static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) |
226 | { | |
c6f7e72a | 227 | return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
228 | } |
229 | ||
230 | static ssize_t store_drivers_autoprobe(struct bus_type *bus, | |
231 | const char *buf, size_t count) | |
232 | { | |
233 | if (buf[0] == '0') | |
c6f7e72a | 234 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 235 | else |
c6f7e72a | 236 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
237 | return count; |
238 | } | |
239 | ||
240 | static ssize_t store_drivers_probe(struct bus_type *bus, | |
241 | const char *buf, size_t count) | |
242 | { | |
243 | struct device *dev; | |
244 | ||
1f9ffc04 | 245 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
246 | if (!dev) |
247 | return -ENODEV; | |
248 | if (bus_rescan_devices_helper(dev, NULL) != 0) | |
249 | return -EINVAL; | |
250 | return count; | |
251 | } | |
2139bdd5 | 252 | #endif |
151ef38f | 253 | |
4a3ad20c | 254 | static struct device *next_device(struct klist_iter *i) |
465c7a3a | 255 | { |
4a3ad20c | 256 | struct klist_node *n = klist_next(i); |
ae1b4171 GKH |
257 | struct device *dev = NULL; |
258 | struct device_private *dev_prv; | |
259 | ||
260 | if (n) { | |
261 | dev_prv = to_device_private_bus(n); | |
262 | dev = dev_prv->device; | |
263 | } | |
264 | return dev; | |
465c7a3a PM |
265 | } |
266 | ||
1da177e4 | 267 | /** |
4a3ad20c GKH |
268 | * bus_for_each_dev - device iterator. |
269 | * @bus: bus type. | |
270 | * @start: device to start iterating from. | |
271 | * @data: data for the callback. | |
272 | * @fn: function to be called for each device. | |
1da177e4 | 273 | * |
4a3ad20c GKH |
274 | * Iterate over @bus's list of devices, and call @fn for each, |
275 | * passing it @data. If @start is not NULL, we use that device to | |
276 | * begin iterating from. | |
1da177e4 | 277 | * |
4a3ad20c GKH |
278 | * We check the return of @fn each time. If it returns anything |
279 | * other than 0, we break out and return that value. | |
1da177e4 | 280 | * |
4a3ad20c GKH |
281 | * NOTE: The device that returns a non-zero value is not retained |
282 | * in any way, nor is its refcount incremented. If the caller needs | |
0fa1b0a1 | 283 | * to retain this data, it should do so, and increment the reference |
4a3ad20c | 284 | * count in the supplied callback. |
1da177e4 | 285 | */ |
4a3ad20c GKH |
286 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
287 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 288 | { |
465c7a3a | 289 | struct klist_iter i; |
4a3ad20c | 290 | struct device *dev; |
465c7a3a | 291 | int error = 0; |
1da177e4 | 292 | |
465c7a3a PM |
293 | if (!bus) |
294 | return -EINVAL; | |
295 | ||
c6f7e72a | 296 | klist_iter_init_node(&bus->p->klist_devices, &i, |
ae1b4171 | 297 | (start ? &start->p->knode_bus : NULL)); |
465c7a3a PM |
298 | while ((dev = next_device(&i)) && !error) |
299 | error = fn(dev, data); | |
300 | klist_iter_exit(&i); | |
301 | return error; | |
1da177e4 | 302 | } |
4a3ad20c | 303 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 304 | |
0edb5860 CH |
305 | /** |
306 | * bus_find_device - device iterator for locating a particular device. | |
307 | * @bus: bus type | |
308 | * @start: Device to begin with | |
309 | * @data: Data to pass to match function | |
310 | * @match: Callback function to check device | |
311 | * | |
312 | * This is similar to the bus_for_each_dev() function above, but it | |
313 | * returns a reference to a device that is 'found' for later use, as | |
314 | * determined by the @match callback. | |
315 | * | |
316 | * The callback should return 0 if the device doesn't match and non-zero | |
317 | * if it does. If the callback returns non-zero, this function will | |
318 | * return to the caller and not iterate over any more devices. | |
319 | */ | |
4a3ad20c GKH |
320 | struct device *bus_find_device(struct bus_type *bus, |
321 | struct device *start, void *data, | |
322 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
323 | { |
324 | struct klist_iter i; | |
325 | struct device *dev; | |
326 | ||
327 | if (!bus) | |
328 | return NULL; | |
329 | ||
c6f7e72a | 330 | klist_iter_init_node(&bus->p->klist_devices, &i, |
ae1b4171 | 331 | (start ? &start->p->knode_bus : NULL)); |
0edb5860 CH |
332 | while ((dev = next_device(&i))) |
333 | if (match(dev, data) && get_device(dev)) | |
334 | break; | |
335 | klist_iter_exit(&i); | |
336 | return dev; | |
337 | } | |
4a3ad20c | 338 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 339 | |
1f9ffc04 GKH |
340 | static int match_name(struct device *dev, void *data) |
341 | { | |
342 | const char *name = data; | |
343 | ||
1e0b2cf9 | 344 | return sysfs_streq(name, dev_name(dev)); |
1f9ffc04 GKH |
345 | } |
346 | ||
347 | /** | |
348 | * bus_find_device_by_name - device iterator for locating a particular device of a specific name | |
349 | * @bus: bus type | |
350 | * @start: Device to begin with | |
351 | * @name: name of the device to match | |
352 | * | |
353 | * This is similar to the bus_find_device() function above, but it handles | |
354 | * searching by a name automatically, no need to write another strcmp matching | |
355 | * function. | |
356 | */ | |
357 | struct device *bus_find_device_by_name(struct bus_type *bus, | |
358 | struct device *start, const char *name) | |
359 | { | |
360 | return bus_find_device(bus, start, (void *)name, match_name); | |
361 | } | |
362 | EXPORT_SYMBOL_GPL(bus_find_device_by_name); | |
363 | ||
4a3ad20c | 364 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 365 | { |
4a3ad20c | 366 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
367 | struct driver_private *drv_priv; |
368 | ||
369 | if (n) { | |
370 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
371 | return drv_priv->driver; | |
372 | } | |
373 | return NULL; | |
38fdac3c PM |
374 | } |
375 | ||
1da177e4 | 376 | /** |
4a3ad20c GKH |
377 | * bus_for_each_drv - driver iterator |
378 | * @bus: bus we're dealing with. | |
379 | * @start: driver to start iterating on. | |
380 | * @data: data to pass to the callback. | |
381 | * @fn: function to call for each driver. | |
1da177e4 | 382 | * |
4a3ad20c GKH |
383 | * This is nearly identical to the device iterator above. |
384 | * We iterate over each driver that belongs to @bus, and call | |
385 | * @fn for each. If @fn returns anything but 0, we break out | |
386 | * and return it. If @start is not NULL, we use it as the head | |
387 | * of the list. | |
1da177e4 | 388 | * |
4a3ad20c GKH |
389 | * NOTE: we don't return the driver that returns a non-zero |
390 | * value, nor do we leave the reference count incremented for that | |
391 | * driver. If the caller needs to know that info, it must set it | |
392 | * in the callback. It must also be sure to increment the refcount | |
393 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 394 | */ |
4a3ad20c GKH |
395 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
396 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 397 | { |
38fdac3c | 398 | struct klist_iter i; |
4a3ad20c | 399 | struct device_driver *drv; |
38fdac3c | 400 | int error = 0; |
1da177e4 | 401 | |
38fdac3c PM |
402 | if (!bus) |
403 | return -EINVAL; | |
404 | ||
c6f7e72a | 405 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
e5dd1278 | 406 | start ? &start->p->knode_bus : NULL); |
38fdac3c PM |
407 | while ((drv = next_driver(&i)) && !error) |
408 | error = fn(drv, data); | |
409 | klist_iter_exit(&i); | |
410 | return error; | |
1da177e4 | 411 | } |
4a3ad20c | 412 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 413 | |
4aca67e5 | 414 | static int device_add_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
415 | { |
416 | int error = 0; | |
417 | int i; | |
418 | ||
4aca67e5 AM |
419 | if (!bus->dev_attrs) |
420 | return 0; | |
421 | ||
422 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) { | |
4a3ad20c | 423 | error = device_create_file(dev, &bus->dev_attrs[i]); |
4aca67e5 AM |
424 | if (error) { |
425 | while (--i >= 0) | |
426 | device_remove_file(dev, &bus->dev_attrs[i]); | |
427 | break; | |
1da177e4 LT |
428 | } |
429 | } | |
1da177e4 | 430 | return error; |
1da177e4 LT |
431 | } |
432 | ||
4a3ad20c | 433 | static void device_remove_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
434 | { |
435 | int i; | |
436 | ||
437 | if (bus->dev_attrs) { | |
438 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) | |
4a3ad20c | 439 | device_remove_file(dev, &bus->dev_attrs[i]); |
1da177e4 LT |
440 | } |
441 | } | |
442 | ||
b9cafc7d KS |
443 | #ifdef CONFIG_SYSFS_DEPRECATED |
444 | static int make_deprecated_bus_links(struct device *dev) | |
445 | { | |
446 | return sysfs_create_link(&dev->kobj, | |
c6f7e72a | 447 | &dev->bus->p->subsys.kobj, "bus"); |
b9cafc7d KS |
448 | } |
449 | ||
450 | static void remove_deprecated_bus_links(struct device *dev) | |
451 | { | |
452 | sysfs_remove_link(&dev->kobj, "bus"); | |
453 | } | |
454 | #else | |
455 | static inline int make_deprecated_bus_links(struct device *dev) { return 0; } | |
456 | static inline void remove_deprecated_bus_links(struct device *dev) { } | |
457 | #endif | |
1da177e4 LT |
458 | |
459 | /** | |
4a3ad20c GKH |
460 | * bus_add_device - add device to bus |
461 | * @dev: device being added | |
1da177e4 | 462 | * |
2023c610 AS |
463 | * - Add device's bus attributes. |
464 | * - Create links to device's bus. | |
4a3ad20c | 465 | * - Add the device to its bus's list of devices. |
1da177e4 | 466 | */ |
4a3ad20c | 467 | int bus_add_device(struct device *dev) |
1da177e4 | 468 | { |
4a3ad20c | 469 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
470 | int error = 0; |
471 | ||
472 | if (bus) { | |
1e0b2cf9 | 473 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
d377e85b | 474 | error = device_add_attrs(bus, dev); |
f86db396 | 475 | if (error) |
513e7337 | 476 | goto out_put; |
c6f7e72a | 477 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 478 | &dev->kobj, dev_name(dev)); |
f86db396 | 479 | if (error) |
513e7337 | 480 | goto out_id; |
f86db396 | 481 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 482 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 483 | if (error) |
513e7337 | 484 | goto out_subsys; |
b9cafc7d | 485 | error = make_deprecated_bus_links(dev); |
513e7337 CH |
486 | if (error) |
487 | goto out_deprecated; | |
2023c610 | 488 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 489 | } |
513e7337 CH |
490 | return 0; |
491 | ||
492 | out_deprecated: | |
493 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
494 | out_subsys: | |
1e0b2cf9 | 495 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
513e7337 CH |
496 | out_id: |
497 | device_remove_attrs(bus, dev); | |
498 | out_put: | |
fc1ede58 | 499 | bus_put(dev->bus); |
1da177e4 LT |
500 | return error; |
501 | } | |
502 | ||
53877d06 | 503 | /** |
2023c610 AS |
504 | * bus_probe_device - probe drivers for a new device |
505 | * @dev: device to probe | |
53877d06 | 506 | * |
2023c610 | 507 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 508 | */ |
2023c610 | 509 | void bus_probe_device(struct device *dev) |
53877d06 | 510 | { |
f86db396 | 511 | struct bus_type *bus = dev->bus; |
2023c610 | 512 | int ret; |
53877d06 | 513 | |
2023c610 AS |
514 | if (bus && bus->p->drivers_autoprobe) { |
515 | ret = device_attach(dev); | |
c6a46696 | 516 | WARN_ON(ret < 0); |
53877d06 KS |
517 | } |
518 | } | |
519 | ||
1da177e4 | 520 | /** |
4a3ad20c GKH |
521 | * bus_remove_device - remove device from bus |
522 | * @dev: device to be removed | |
1da177e4 | 523 | * |
4a3ad20c GKH |
524 | * - Remove symlink from bus's directory. |
525 | * - Delete device from bus's list. | |
526 | * - Detach from its driver. | |
527 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 528 | */ |
4a3ad20c | 529 | void bus_remove_device(struct device *dev) |
1da177e4 LT |
530 | { |
531 | if (dev->bus) { | |
b9d9c82b | 532 | sysfs_remove_link(&dev->kobj, "subsystem"); |
b9cafc7d | 533 | remove_deprecated_bus_links(dev); |
4a3ad20c | 534 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, |
1e0b2cf9 | 535 | dev_name(dev)); |
1da177e4 | 536 | device_remove_attrs(dev->bus, dev); |
ae1b4171 GKH |
537 | if (klist_node_attached(&dev->p->knode_bus)) |
538 | klist_del(&dev->p->knode_bus); | |
3f62e570 | 539 | |
4a3ad20c | 540 | pr_debug("bus: '%s': remove device %s\n", |
1e0b2cf9 | 541 | dev->bus->name, dev_name(dev)); |
1da177e4 | 542 | device_release_driver(dev); |
fc1ede58 | 543 | bus_put(dev->bus); |
1da177e4 LT |
544 | } |
545 | } | |
546 | ||
4a3ad20c | 547 | static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv) |
1da177e4 LT |
548 | { |
549 | int error = 0; | |
550 | int i; | |
551 | ||
552 | if (bus->drv_attrs) { | |
553 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) { | |
554 | error = driver_create_file(drv, &bus->drv_attrs[i]); | |
555 | if (error) | |
4a3ad20c | 556 | goto err; |
1da177e4 LT |
557 | } |
558 | } | |
4a3ad20c | 559 | done: |
1da177e4 | 560 | return error; |
4a3ad20c | 561 | err: |
1da177e4 LT |
562 | while (--i >= 0) |
563 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
4a3ad20c | 564 | goto done; |
1da177e4 LT |
565 | } |
566 | ||
4a3ad20c GKH |
567 | static void driver_remove_attrs(struct bus_type *bus, |
568 | struct device_driver *drv) | |
1da177e4 LT |
569 | { |
570 | int i; | |
571 | ||
572 | if (bus->drv_attrs) { | |
573 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) | |
574 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
575 | } | |
576 | } | |
577 | ||
874c6241 GKH |
578 | #ifdef CONFIG_HOTPLUG |
579 | /* | |
580 | * Thanks to drivers making their tables __devinit, we can't allow manual | |
581 | * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. | |
582 | */ | |
f86db396 | 583 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 584 | { |
f86db396 AM |
585 | int ret; |
586 | ||
587 | ret = driver_create_file(drv, &driver_attr_unbind); | |
588 | if (ret == 0) { | |
589 | ret = driver_create_file(drv, &driver_attr_bind); | |
590 | if (ret) | |
591 | driver_remove_file(drv, &driver_attr_unbind); | |
592 | } | |
593 | return ret; | |
874c6241 GKH |
594 | } |
595 | ||
596 | static void remove_bind_files(struct device_driver *drv) | |
597 | { | |
598 | driver_remove_file(drv, &driver_attr_bind); | |
599 | driver_remove_file(drv, &driver_attr_unbind); | |
600 | } | |
b8c5cec2 | 601 | |
8380770c KS |
602 | static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); |
603 | static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, | |
604 | show_drivers_autoprobe, store_drivers_autoprobe); | |
605 | ||
b8c5cec2 KS |
606 | static int add_probe_files(struct bus_type *bus) |
607 | { | |
608 | int retval; | |
609 | ||
8380770c | 610 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
611 | if (retval) |
612 | goto out; | |
613 | ||
8380770c | 614 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 615 | if (retval) |
8380770c | 616 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
617 | out: |
618 | return retval; | |
619 | } | |
620 | ||
621 | static void remove_probe_files(struct bus_type *bus) | |
622 | { | |
8380770c KS |
623 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
624 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 625 | } |
874c6241 | 626 | #else |
35acfdd7 | 627 | static inline int add_bind_files(struct device_driver *drv) { return 0; } |
874c6241 | 628 | static inline void remove_bind_files(struct device_driver *drv) {} |
b8c5cec2 KS |
629 | static inline int add_probe_files(struct bus_type *bus) { return 0; } |
630 | static inline void remove_probe_files(struct bus_type *bus) {} | |
874c6241 | 631 | #endif |
1da177e4 | 632 | |
7ac1cf4a KS |
633 | static ssize_t driver_uevent_store(struct device_driver *drv, |
634 | const char *buf, size_t count) | |
635 | { | |
636 | enum kobject_action action; | |
637 | ||
638 | if (kobject_action_type(buf, count, &action) == 0) | |
e5dd1278 | 639 | kobject_uevent(&drv->p->kobj, action); |
7ac1cf4a KS |
640 | return count; |
641 | } | |
642 | static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store); | |
643 | ||
1da177e4 | 644 | /** |
4a3ad20c GKH |
645 | * bus_add_driver - Add a driver to the bus. |
646 | * @drv: driver. | |
1da177e4 | 647 | */ |
f86db396 | 648 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 649 | { |
e5dd1278 GKH |
650 | struct bus_type *bus; |
651 | struct driver_private *priv; | |
1da177e4 LT |
652 | int error = 0; |
653 | ||
e5dd1278 | 654 | bus = bus_get(drv->bus); |
d9fd4d3b | 655 | if (!bus) |
4f6e1945 | 656 | return -EINVAL; |
d9fd4d3b | 657 | |
7dc72b28 | 658 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
659 | |
660 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
661 | if (!priv) { |
662 | error = -ENOMEM; | |
663 | goto out_put_bus; | |
664 | } | |
e5dd1278 GKH |
665 | klist_init(&priv->klist_devices, NULL, NULL); |
666 | priv->driver = drv; | |
667 | drv->p = priv; | |
c8e90d82 GKH |
668 | priv->kobj.kset = bus->p->drivers_kset; |
669 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
670 | "%s", drv->name); | |
dc0afa83 | 671 | if (error) |
07634464 | 672 | goto out_unregister; |
d9fd4d3b | 673 | |
c6f7e72a | 674 | if (drv->bus->p->drivers_autoprobe) { |
b8c5cec2 KS |
675 | error = driver_attach(drv); |
676 | if (error) | |
677 | goto out_unregister; | |
678 | } | |
e5dd1278 | 679 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
d9fd4d3b JG |
680 | module_add_driver(drv->owner, drv); |
681 | ||
7ac1cf4a KS |
682 | error = driver_create_file(drv, &driver_attr_uevent); |
683 | if (error) { | |
684 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 685 | __func__, drv->name); |
7ac1cf4a | 686 | } |
d9fd4d3b JG |
687 | error = driver_add_attrs(bus, drv); |
688 | if (error) { | |
689 | /* How the hell do we get out of this pickle? Give up */ | |
690 | printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", | |
2b3a302a | 691 | __func__, drv->name); |
d9fd4d3b | 692 | } |
1a6f2a75 DT |
693 | |
694 | if (!drv->suppress_bind_attrs) { | |
695 | error = add_bind_files(drv); | |
696 | if (error) { | |
697 | /* Ditto */ | |
698 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
699 | __func__, drv->name); | |
700 | } | |
1da177e4 | 701 | } |
d9fd4d3b | 702 | |
c8e90d82 | 703 | kobject_uevent(&priv->kobj, KOBJ_ADD); |
5c8563d7 | 704 | return 0; |
1a6f2a75 | 705 | |
f86db396 | 706 | out_unregister: |
99b28f1b | 707 | kobject_put(&priv->kobj); |
5c8563d7 KS |
708 | kfree(drv->p); |
709 | drv->p = NULL; | |
f86db396 | 710 | out_put_bus: |
fc1ede58 | 711 | bus_put(bus); |
f86db396 | 712 | return error; |
1da177e4 LT |
713 | } |
714 | ||
1da177e4 | 715 | /** |
4a3ad20c GKH |
716 | * bus_remove_driver - delete driver from bus's knowledge. |
717 | * @drv: driver. | |
1da177e4 | 718 | * |
4a3ad20c GKH |
719 | * Detach the driver from the devices it controls, and remove |
720 | * it from its bus's list of drivers. Finally, we drop the reference | |
721 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 722 | */ |
4a3ad20c | 723 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 724 | { |
d9fd4d3b JG |
725 | if (!drv->bus) |
726 | return; | |
727 | ||
1a6f2a75 DT |
728 | if (!drv->suppress_bind_attrs) |
729 | remove_bind_files(drv); | |
d9fd4d3b | 730 | driver_remove_attrs(drv->bus, drv); |
7ac1cf4a | 731 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 732 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 733 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
734 | driver_detach(drv); |
735 | module_remove_driver(drv); | |
c10997f6 | 736 | kobject_put(&drv->p->kobj); |
fc1ede58 | 737 | bus_put(drv->bus); |
1da177e4 LT |
738 | } |
739 | ||
1da177e4 | 740 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 741 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 742 | void *data) |
1da177e4 | 743 | { |
f86db396 AM |
744 | int ret = 0; |
745 | ||
bf74ad5b AS |
746 | if (!dev->driver) { |
747 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 748 | device_lock(dev->parent); |
f86db396 | 749 | ret = device_attach(dev); |
bf74ad5b | 750 | if (dev->parent) |
8e9394ce | 751 | device_unlock(dev->parent); |
bf74ad5b | 752 | } |
f86db396 | 753 | return ret < 0 ? ret : 0; |
1da177e4 LT |
754 | } |
755 | ||
1da177e4 | 756 | /** |
23d3d602 GKH |
757 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
758 | * @bus: the bus to scan. | |
1da177e4 | 759 | * |
23d3d602 GKH |
760 | * This function will look for devices on the bus with no driver |
761 | * attached and rescan it against existing drivers to see if it matches | |
762 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 763 | */ |
4a3ad20c | 764 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 765 | { |
f86db396 | 766 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 767 | } |
4a3ad20c | 768 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 769 | |
e935d5da ME |
770 | /** |
771 | * device_reprobe - remove driver for a device and probe for a new driver | |
772 | * @dev: the device to reprobe | |
773 | * | |
774 | * This function detaches the attached driver (if any) for the given | |
775 | * device and restarts the driver probing process. It is intended | |
776 | * to use if probing criteria changed during a devices lifetime and | |
777 | * driver attachment should change accordingly. | |
778 | */ | |
f86db396 | 779 | int device_reprobe(struct device *dev) |
e935d5da ME |
780 | { |
781 | if (dev->driver) { | |
782 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 783 | device_lock(dev->parent); |
e935d5da ME |
784 | device_release_driver(dev); |
785 | if (dev->parent) | |
8e9394ce | 786 | device_unlock(dev->parent); |
e935d5da | 787 | } |
f86db396 | 788 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
789 | } |
790 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 791 | |
1da177e4 | 792 | /** |
4a3ad20c GKH |
793 | * find_bus - locate bus by name. |
794 | * @name: name of bus. | |
1da177e4 | 795 | * |
4a3ad20c GKH |
796 | * Call kset_find_obj() to iterate over list of buses to |
797 | * find a bus by name. Return bus if found. | |
1da177e4 | 798 | * |
4a3ad20c | 799 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 800 | */ |
7e4ef085 | 801 | #if 0 |
4a3ad20c | 802 | struct bus_type *find_bus(char *name) |
1da177e4 | 803 | { |
4a3ad20c | 804 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
805 | return k ? to_bus(k) : NULL; |
806 | } | |
7e4ef085 | 807 | #endif /* 0 */ |
1da177e4 LT |
808 | |
809 | ||
810 | /** | |
4a3ad20c GKH |
811 | * bus_add_attrs - Add default attributes for this bus. |
812 | * @bus: Bus that has just been registered. | |
1da177e4 LT |
813 | */ |
814 | ||
4a3ad20c | 815 | static int bus_add_attrs(struct bus_type *bus) |
1da177e4 LT |
816 | { |
817 | int error = 0; | |
818 | int i; | |
819 | ||
820 | if (bus->bus_attrs) { | |
821 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) { | |
4a3ad20c | 822 | error = bus_create_file(bus, &bus->bus_attrs[i]); |
dc0afa83 | 823 | if (error) |
4a3ad20c | 824 | goto err; |
1da177e4 LT |
825 | } |
826 | } | |
4a3ad20c | 827 | done: |
1da177e4 | 828 | return error; |
4a3ad20c | 829 | err: |
1da177e4 | 830 | while (--i >= 0) |
4a3ad20c GKH |
831 | bus_remove_file(bus, &bus->bus_attrs[i]); |
832 | goto done; | |
1da177e4 LT |
833 | } |
834 | ||
4a3ad20c | 835 | static void bus_remove_attrs(struct bus_type *bus) |
1da177e4 LT |
836 | { |
837 | int i; | |
838 | ||
839 | if (bus->bus_attrs) { | |
840 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) | |
4a3ad20c | 841 | bus_remove_file(bus, &bus->bus_attrs[i]); |
1da177e4 LT |
842 | } |
843 | } | |
844 | ||
34bb61f9 JB |
845 | static void klist_devices_get(struct klist_node *n) |
846 | { | |
ae1b4171 GKH |
847 | struct device_private *dev_prv = to_device_private_bus(n); |
848 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
849 | |
850 | get_device(dev); | |
851 | } | |
852 | ||
853 | static void klist_devices_put(struct klist_node *n) | |
854 | { | |
ae1b4171 GKH |
855 | struct device_private *dev_prv = to_device_private_bus(n); |
856 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
857 | |
858 | put_device(dev); | |
859 | } | |
860 | ||
7ac1cf4a KS |
861 | static ssize_t bus_uevent_store(struct bus_type *bus, |
862 | const char *buf, size_t count) | |
863 | { | |
864 | enum kobject_action action; | |
865 | ||
866 | if (kobject_action_type(buf, count, &action) == 0) | |
c6f7e72a | 867 | kobject_uevent(&bus->p->subsys.kobj, action); |
7ac1cf4a KS |
868 | return count; |
869 | } | |
870 | static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); | |
871 | ||
1da177e4 | 872 | /** |
4a3ad20c GKH |
873 | * bus_register - register a bus with the system. |
874 | * @bus: bus. | |
1da177e4 | 875 | * |
4a3ad20c GKH |
876 | * Once we have that, we registered the bus with the kobject |
877 | * infrastructure, then register the children subsystems it has: | |
878 | * the devices and drivers that belong to the bus. | |
1da177e4 | 879 | */ |
4a3ad20c | 880 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
881 | { |
882 | int retval; | |
c6f7e72a GKH |
883 | struct bus_type_private *priv; |
884 | ||
885 | priv = kzalloc(sizeof(struct bus_type_private), GFP_KERNEL); | |
886 | if (!priv) | |
887 | return -ENOMEM; | |
888 | ||
889 | priv->bus = bus; | |
890 | bus->p = priv; | |
1da177e4 | 891 | |
c6f7e72a | 892 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 893 | |
c6f7e72a | 894 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
895 | if (retval) |
896 | goto out; | |
897 | ||
c6f7e72a GKH |
898 | priv->subsys.kobj.kset = bus_kset; |
899 | priv->subsys.kobj.ktype = &bus_ktype; | |
900 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 901 | |
c6f7e72a | 902 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
903 | if (retval) |
904 | goto out; | |
905 | ||
7ac1cf4a KS |
906 | retval = bus_create_file(bus, &bus_attr_uevent); |
907 | if (retval) | |
908 | goto bus_uevent_fail; | |
909 | ||
c6f7e72a GKH |
910 | priv->devices_kset = kset_create_and_add("devices", NULL, |
911 | &priv->subsys.kobj); | |
912 | if (!priv->devices_kset) { | |
3d899596 | 913 | retval = -ENOMEM; |
1da177e4 | 914 | goto bus_devices_fail; |
3d899596 | 915 | } |
1da177e4 | 916 | |
c6f7e72a GKH |
917 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
918 | &priv->subsys.kobj); | |
919 | if (!priv->drivers_kset) { | |
6dcec251 | 920 | retval = -ENOMEM; |
1da177e4 | 921 | goto bus_drivers_fail; |
6dcec251 | 922 | } |
465c7a3a | 923 | |
c6f7e72a GKH |
924 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
925 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 926 | |
b8c5cec2 KS |
927 | retval = add_probe_files(bus); |
928 | if (retval) | |
929 | goto bus_probe_files_fail; | |
930 | ||
1bb6881a CH |
931 | retval = bus_add_attrs(bus); |
932 | if (retval) | |
933 | goto bus_attrs_fail; | |
1da177e4 | 934 | |
7dc72b28 | 935 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
936 | return 0; |
937 | ||
1bb6881a | 938 | bus_attrs_fail: |
b8c5cec2 KS |
939 | remove_probe_files(bus); |
940 | bus_probe_files_fail: | |
c6f7e72a | 941 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 942 | bus_drivers_fail: |
c6f7e72a | 943 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 944 | bus_devices_fail: |
7ac1cf4a KS |
945 | bus_remove_file(bus, &bus_attr_uevent); |
946 | bus_uevent_fail: | |
c6f7e72a GKH |
947 | kset_unregister(&bus->p->subsys); |
948 | kfree(bus->p); | |
1da177e4 | 949 | out: |
f48f3feb | 950 | bus->p = NULL; |
1da177e4 LT |
951 | return retval; |
952 | } | |
4a3ad20c | 953 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 954 | |
1da177e4 | 955 | /** |
4a3ad20c GKH |
956 | * bus_unregister - remove a bus from the system |
957 | * @bus: bus. | |
1da177e4 | 958 | * |
4a3ad20c GKH |
959 | * Unregister the child subsystems and the bus itself. |
960 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 961 | */ |
4a3ad20c | 962 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 963 | { |
7dc72b28 | 964 | pr_debug("bus: '%s': unregistering\n", bus->name); |
1da177e4 | 965 | bus_remove_attrs(bus); |
b8c5cec2 | 966 | remove_probe_files(bus); |
c6f7e72a GKH |
967 | kset_unregister(bus->p->drivers_kset); |
968 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 969 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a GKH |
970 | kset_unregister(&bus->p->subsys); |
971 | kfree(bus->p); | |
f48f3feb | 972 | bus->p = NULL; |
1da177e4 | 973 | } |
4a3ad20c | 974 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 975 | |
116af378 BH |
976 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
977 | { | |
c6f7e72a | 978 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
979 | } |
980 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
981 | ||
982 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
983 | { | |
c6f7e72a | 984 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
985 | } |
986 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
987 | ||
0fed80f7 GKH |
988 | struct kset *bus_get_kset(struct bus_type *bus) |
989 | { | |
c6f7e72a | 990 | return &bus->p->subsys; |
0fed80f7 GKH |
991 | } |
992 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
993 | ||
b249072e GKH |
994 | struct klist *bus_get_device_klist(struct bus_type *bus) |
995 | { | |
c6f7e72a | 996 | return &bus->p->klist_devices; |
b249072e GKH |
997 | } |
998 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
999 | ||
99178b03 GKH |
1000 | /* |
1001 | * Yes, this forcably breaks the klist abstraction temporarily. It | |
1002 | * just wants to sort the klist, not change reference counts and | |
1003 | * take/drop locks rapidly in the process. It does all this while | |
1004 | * holding the lock for the list, so objects can't otherwise be | |
1005 | * added/removed while we're swizzling. | |
1006 | */ | |
1007 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
1008 | int (*compare)(const struct device *a, | |
1009 | const struct device *b)) | |
1010 | { | |
1011 | struct list_head *pos; | |
1012 | struct klist_node *n; | |
ae1b4171 | 1013 | struct device_private *dev_prv; |
99178b03 GKH |
1014 | struct device *b; |
1015 | ||
1016 | list_for_each(pos, list) { | |
1017 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1018 | dev_prv = to_device_private_bus(n); |
1019 | b = dev_prv->device; | |
99178b03 | 1020 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
1021 | list_move_tail(&a->p->knode_bus.n_node, |
1022 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
1023 | return; |
1024 | } | |
1025 | } | |
ae1b4171 | 1026 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
1027 | } |
1028 | ||
1029 | void bus_sort_breadthfirst(struct bus_type *bus, | |
1030 | int (*compare)(const struct device *a, | |
1031 | const struct device *b)) | |
1032 | { | |
1033 | LIST_HEAD(sorted_devices); | |
1034 | struct list_head *pos, *tmp; | |
1035 | struct klist_node *n; | |
ae1b4171 | 1036 | struct device_private *dev_prv; |
99178b03 GKH |
1037 | struct device *dev; |
1038 | struct klist *device_klist; | |
1039 | ||
1040 | device_klist = bus_get_device_klist(bus); | |
1041 | ||
1042 | spin_lock(&device_klist->k_lock); | |
1043 | list_for_each_safe(pos, tmp, &device_klist->k_list) { | |
1044 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1045 | dev_prv = to_device_private_bus(n); |
1046 | dev = dev_prv->device; | |
99178b03 GKH |
1047 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
1048 | } | |
1049 | list_splice(&sorted_devices, &device_klist->k_list); | |
1050 | spin_unlock(&device_klist->k_lock); | |
1051 | } | |
1052 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
1053 | ||
1da177e4 LT |
1054 | int __init buses_init(void) |
1055 | { | |
59a54833 GKH |
1056 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1057 | if (!bus_kset) | |
1058 | return -ENOMEM; | |
1059 | return 0; | |
1da177e4 | 1060 | } |