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 | ||
7dc72b28 | 82 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __FUNCTION__); |
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); |
2b08c8d0 | 201 | if (dev && dev->driver == NULL) { |
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); |
465c7a3a | 256 | return n ? container_of(n, struct device, knode_bus) : NULL; |
257 | } | |
258 | ||
1da177e4 | 259 | /** |
4a3ad20c GKH |
260 | * bus_for_each_dev - device iterator. |
261 | * @bus: bus type. | |
262 | * @start: device to start iterating from. | |
263 | * @data: data for the callback. | |
264 | * @fn: function to be called for each device. | |
1da177e4 | 265 | * |
4a3ad20c GKH |
266 | * Iterate over @bus's list of devices, and call @fn for each, |
267 | * passing it @data. If @start is not NULL, we use that device to | |
268 | * begin iterating from. | |
1da177e4 | 269 | * |
4a3ad20c GKH |
270 | * We check the return of @fn each time. If it returns anything |
271 | * other than 0, we break out and return that value. | |
1da177e4 | 272 | * |
4a3ad20c GKH |
273 | * NOTE: The device that returns a non-zero value is not retained |
274 | * in any way, nor is its refcount incremented. If the caller needs | |
275 | * to retain this data, it should do, and increment the reference | |
276 | * count in the supplied callback. | |
1da177e4 | 277 | */ |
4a3ad20c GKH |
278 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
279 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 280 | { |
465c7a3a | 281 | struct klist_iter i; |
4a3ad20c | 282 | struct device *dev; |
465c7a3a | 283 | int error = 0; |
1da177e4 | 284 | |
465c7a3a | 285 | if (!bus) |
286 | return -EINVAL; | |
287 | ||
c6f7e72a | 288 | klist_iter_init_node(&bus->p->klist_devices, &i, |
465c7a3a | 289 | (start ? &start->knode_bus : NULL)); |
290 | while ((dev = next_device(&i)) && !error) | |
291 | error = fn(dev, data); | |
292 | klist_iter_exit(&i); | |
293 | return error; | |
1da177e4 | 294 | } |
4a3ad20c | 295 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 296 | |
0edb5860 CH |
297 | /** |
298 | * bus_find_device - device iterator for locating a particular device. | |
299 | * @bus: bus type | |
300 | * @start: Device to begin with | |
301 | * @data: Data to pass to match function | |
302 | * @match: Callback function to check device | |
303 | * | |
304 | * This is similar to the bus_for_each_dev() function above, but it | |
305 | * returns a reference to a device that is 'found' for later use, as | |
306 | * determined by the @match callback. | |
307 | * | |
308 | * The callback should return 0 if the device doesn't match and non-zero | |
309 | * if it does. If the callback returns non-zero, this function will | |
310 | * return to the caller and not iterate over any more devices. | |
311 | */ | |
4a3ad20c GKH |
312 | struct device *bus_find_device(struct bus_type *bus, |
313 | struct device *start, void *data, | |
314 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
315 | { |
316 | struct klist_iter i; | |
317 | struct device *dev; | |
318 | ||
319 | if (!bus) | |
320 | return NULL; | |
321 | ||
c6f7e72a | 322 | klist_iter_init_node(&bus->p->klist_devices, &i, |
0edb5860 CH |
323 | (start ? &start->knode_bus : NULL)); |
324 | while ((dev = next_device(&i))) | |
325 | if (match(dev, data) && get_device(dev)) | |
326 | break; | |
327 | klist_iter_exit(&i); | |
328 | return dev; | |
329 | } | |
4a3ad20c | 330 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 331 | |
1f9ffc04 GKH |
332 | static int match_name(struct device *dev, void *data) |
333 | { | |
334 | const char *name = data; | |
335 | ||
336 | if (strcmp(name, dev->bus_id) == 0) | |
337 | return 1; | |
338 | return 0; | |
339 | } | |
340 | ||
341 | /** | |
342 | * bus_find_device_by_name - device iterator for locating a particular device of a specific name | |
343 | * @bus: bus type | |
344 | * @start: Device to begin with | |
345 | * @name: name of the device to match | |
346 | * | |
347 | * This is similar to the bus_find_device() function above, but it handles | |
348 | * searching by a name automatically, no need to write another strcmp matching | |
349 | * function. | |
350 | */ | |
351 | struct device *bus_find_device_by_name(struct bus_type *bus, | |
352 | struct device *start, const char *name) | |
353 | { | |
354 | return bus_find_device(bus, start, (void *)name, match_name); | |
355 | } | |
356 | EXPORT_SYMBOL_GPL(bus_find_device_by_name); | |
357 | ||
4a3ad20c | 358 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 359 | { |
4a3ad20c | 360 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
361 | struct driver_private *drv_priv; |
362 | ||
363 | if (n) { | |
364 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
365 | return drv_priv->driver; | |
366 | } | |
367 | return NULL; | |
38fdac3c | 368 | } |
369 | ||
1da177e4 | 370 | /** |
4a3ad20c GKH |
371 | * bus_for_each_drv - driver iterator |
372 | * @bus: bus we're dealing with. | |
373 | * @start: driver to start iterating on. | |
374 | * @data: data to pass to the callback. | |
375 | * @fn: function to call for each driver. | |
1da177e4 | 376 | * |
4a3ad20c GKH |
377 | * This is nearly identical to the device iterator above. |
378 | * We iterate over each driver that belongs to @bus, and call | |
379 | * @fn for each. If @fn returns anything but 0, we break out | |
380 | * and return it. If @start is not NULL, we use it as the head | |
381 | * of the list. | |
1da177e4 | 382 | * |
4a3ad20c GKH |
383 | * NOTE: we don't return the driver that returns a non-zero |
384 | * value, nor do we leave the reference count incremented for that | |
385 | * driver. If the caller needs to know that info, it must set it | |
386 | * in the callback. It must also be sure to increment the refcount | |
387 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 388 | */ |
4a3ad20c GKH |
389 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
390 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 391 | { |
38fdac3c | 392 | struct klist_iter i; |
4a3ad20c | 393 | struct device_driver *drv; |
38fdac3c | 394 | int error = 0; |
1da177e4 | 395 | |
38fdac3c | 396 | if (!bus) |
397 | return -EINVAL; | |
398 | ||
c6f7e72a | 399 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
e5dd1278 | 400 | start ? &start->p->knode_bus : NULL); |
38fdac3c | 401 | while ((drv = next_driver(&i)) && !error) |
402 | error = fn(drv, data); | |
403 | klist_iter_exit(&i); | |
404 | return error; | |
1da177e4 | 405 | } |
4a3ad20c | 406 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 407 | |
4aca67e5 | 408 | static int device_add_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
409 | { |
410 | int error = 0; | |
411 | int i; | |
412 | ||
4aca67e5 AM |
413 | if (!bus->dev_attrs) |
414 | return 0; | |
415 | ||
416 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) { | |
4a3ad20c | 417 | error = device_create_file(dev, &bus->dev_attrs[i]); |
4aca67e5 AM |
418 | if (error) { |
419 | while (--i >= 0) | |
420 | device_remove_file(dev, &bus->dev_attrs[i]); | |
421 | break; | |
1da177e4 LT |
422 | } |
423 | } | |
1da177e4 | 424 | return error; |
1da177e4 LT |
425 | } |
426 | ||
4a3ad20c | 427 | static void device_remove_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
428 | { |
429 | int i; | |
430 | ||
431 | if (bus->dev_attrs) { | |
432 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) | |
4a3ad20c | 433 | device_remove_file(dev, &bus->dev_attrs[i]); |
1da177e4 LT |
434 | } |
435 | } | |
436 | ||
b9cafc7d KS |
437 | #ifdef CONFIG_SYSFS_DEPRECATED |
438 | static int make_deprecated_bus_links(struct device *dev) | |
439 | { | |
440 | return sysfs_create_link(&dev->kobj, | |
c6f7e72a | 441 | &dev->bus->p->subsys.kobj, "bus"); |
b9cafc7d KS |
442 | } |
443 | ||
444 | static void remove_deprecated_bus_links(struct device *dev) | |
445 | { | |
446 | sysfs_remove_link(&dev->kobj, "bus"); | |
447 | } | |
448 | #else | |
449 | static inline int make_deprecated_bus_links(struct device *dev) { return 0; } | |
450 | static inline void remove_deprecated_bus_links(struct device *dev) { } | |
451 | #endif | |
1da177e4 LT |
452 | |
453 | /** | |
4a3ad20c GKH |
454 | * bus_add_device - add device to bus |
455 | * @dev: device being added | |
1da177e4 | 456 | * |
4a3ad20c GKH |
457 | * - Add the device to its bus's list of devices. |
458 | * - Create link to device's bus. | |
1da177e4 | 459 | */ |
4a3ad20c | 460 | int bus_add_device(struct device *dev) |
1da177e4 | 461 | { |
4a3ad20c | 462 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
463 | int error = 0; |
464 | ||
465 | if (bus) { | |
7dc72b28 | 466 | pr_debug("bus: '%s': add device %s\n", bus->name, dev->bus_id); |
d377e85b | 467 | error = device_add_attrs(bus, dev); |
f86db396 | 468 | if (error) |
513e7337 | 469 | goto out_put; |
c6f7e72a | 470 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
f86db396 AM |
471 | &dev->kobj, dev->bus_id); |
472 | if (error) | |
513e7337 | 473 | goto out_id; |
f86db396 | 474 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 475 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 476 | if (error) |
513e7337 | 477 | goto out_subsys; |
b9cafc7d | 478 | error = make_deprecated_bus_links(dev); |
513e7337 CH |
479 | if (error) |
480 | goto out_deprecated; | |
1da177e4 | 481 | } |
513e7337 CH |
482 | return 0; |
483 | ||
484 | out_deprecated: | |
485 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
486 | out_subsys: | |
c6f7e72a | 487 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev->bus_id); |
513e7337 CH |
488 | out_id: |
489 | device_remove_attrs(bus, dev); | |
490 | out_put: | |
fc1ede58 | 491 | bus_put(dev->bus); |
1da177e4 LT |
492 | return error; |
493 | } | |
494 | ||
53877d06 | 495 | /** |
4a3ad20c GKH |
496 | * bus_attach_device - add device to bus |
497 | * @dev: device tried to attach to a driver | |
53877d06 | 498 | * |
4a3ad20c GKH |
499 | * - Add device to bus's list of devices. |
500 | * - Try to attach to driver. | |
53877d06 | 501 | */ |
4a3ad20c | 502 | void bus_attach_device(struct device *dev) |
53877d06 | 503 | { |
f86db396 AM |
504 | struct bus_type *bus = dev->bus; |
505 | int ret = 0; | |
53877d06 KS |
506 | |
507 | if (bus) { | |
c6f7e72a | 508 | if (bus->p->drivers_autoprobe) |
b8c5cec2 | 509 | ret = device_attach(dev); |
c6a46696 CH |
510 | WARN_ON(ret < 0); |
511 | if (ret >= 0) | |
c6f7e72a | 512 | klist_add_tail(&dev->knode_bus, &bus->p->klist_devices); |
53877d06 KS |
513 | } |
514 | } | |
515 | ||
1da177e4 | 516 | /** |
4a3ad20c GKH |
517 | * bus_remove_device - remove device from bus |
518 | * @dev: device to be removed | |
1da177e4 | 519 | * |
4a3ad20c GKH |
520 | * - Remove symlink from bus's directory. |
521 | * - Delete device from bus's list. | |
522 | * - Detach from its driver. | |
523 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 524 | */ |
4a3ad20c | 525 | void bus_remove_device(struct device *dev) |
1da177e4 LT |
526 | { |
527 | if (dev->bus) { | |
b9d9c82b | 528 | sysfs_remove_link(&dev->kobj, "subsystem"); |
b9cafc7d | 529 | remove_deprecated_bus_links(dev); |
4a3ad20c GKH |
530 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, |
531 | dev->bus_id); | |
1da177e4 | 532 | device_remove_attrs(dev->bus, dev); |
3f62e570 GKH |
533 | klist_del(&dev->knode_bus); |
534 | ||
4a3ad20c GKH |
535 | pr_debug("bus: '%s': remove device %s\n", |
536 | dev->bus->name, dev->bus_id); | |
1da177e4 | 537 | device_release_driver(dev); |
fc1ede58 | 538 | bus_put(dev->bus); |
1da177e4 LT |
539 | } |
540 | } | |
541 | ||
4a3ad20c | 542 | static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv) |
1da177e4 LT |
543 | { |
544 | int error = 0; | |
545 | int i; | |
546 | ||
547 | if (bus->drv_attrs) { | |
548 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) { | |
549 | error = driver_create_file(drv, &bus->drv_attrs[i]); | |
550 | if (error) | |
4a3ad20c | 551 | goto err; |
1da177e4 LT |
552 | } |
553 | } | |
4a3ad20c | 554 | done: |
1da177e4 | 555 | return error; |
4a3ad20c | 556 | err: |
1da177e4 LT |
557 | while (--i >= 0) |
558 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
4a3ad20c | 559 | goto done; |
1da177e4 LT |
560 | } |
561 | ||
4a3ad20c GKH |
562 | static void driver_remove_attrs(struct bus_type *bus, |
563 | struct device_driver *drv) | |
1da177e4 LT |
564 | { |
565 | int i; | |
566 | ||
567 | if (bus->drv_attrs) { | |
568 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) | |
569 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
570 | } | |
571 | } | |
572 | ||
874c6241 GKH |
573 | #ifdef CONFIG_HOTPLUG |
574 | /* | |
575 | * Thanks to drivers making their tables __devinit, we can't allow manual | |
576 | * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. | |
577 | */ | |
f86db396 | 578 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 579 | { |
f86db396 AM |
580 | int ret; |
581 | ||
582 | ret = driver_create_file(drv, &driver_attr_unbind); | |
583 | if (ret == 0) { | |
584 | ret = driver_create_file(drv, &driver_attr_bind); | |
585 | if (ret) | |
586 | driver_remove_file(drv, &driver_attr_unbind); | |
587 | } | |
588 | return ret; | |
874c6241 GKH |
589 | } |
590 | ||
591 | static void remove_bind_files(struct device_driver *drv) | |
592 | { | |
593 | driver_remove_file(drv, &driver_attr_bind); | |
594 | driver_remove_file(drv, &driver_attr_unbind); | |
595 | } | |
b8c5cec2 | 596 | |
8380770c KS |
597 | static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); |
598 | static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, | |
599 | show_drivers_autoprobe, store_drivers_autoprobe); | |
600 | ||
b8c5cec2 KS |
601 | static int add_probe_files(struct bus_type *bus) |
602 | { | |
603 | int retval; | |
604 | ||
8380770c | 605 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
606 | if (retval) |
607 | goto out; | |
608 | ||
8380770c | 609 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 610 | if (retval) |
8380770c | 611 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
612 | out: |
613 | return retval; | |
614 | } | |
615 | ||
616 | static void remove_probe_files(struct bus_type *bus) | |
617 | { | |
8380770c KS |
618 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
619 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 620 | } |
874c6241 | 621 | #else |
35acfdd7 | 622 | static inline int add_bind_files(struct device_driver *drv) { return 0; } |
874c6241 | 623 | static inline void remove_bind_files(struct device_driver *drv) {} |
b8c5cec2 KS |
624 | static inline int add_probe_files(struct bus_type *bus) { return 0; } |
625 | static inline void remove_probe_files(struct bus_type *bus) {} | |
874c6241 | 626 | #endif |
1da177e4 | 627 | |
7ac1cf4a KS |
628 | static ssize_t driver_uevent_store(struct device_driver *drv, |
629 | const char *buf, size_t count) | |
630 | { | |
631 | enum kobject_action action; | |
632 | ||
633 | if (kobject_action_type(buf, count, &action) == 0) | |
e5dd1278 | 634 | kobject_uevent(&drv->p->kobj, action); |
7ac1cf4a KS |
635 | return count; |
636 | } | |
637 | static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store); | |
638 | ||
1da177e4 | 639 | /** |
4a3ad20c GKH |
640 | * bus_add_driver - Add a driver to the bus. |
641 | * @drv: driver. | |
1da177e4 | 642 | */ |
f86db396 | 643 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 644 | { |
e5dd1278 GKH |
645 | struct bus_type *bus; |
646 | struct driver_private *priv; | |
1da177e4 LT |
647 | int error = 0; |
648 | ||
e5dd1278 | 649 | bus = bus_get(drv->bus); |
d9fd4d3b | 650 | if (!bus) |
4f6e1945 | 651 | return -EINVAL; |
d9fd4d3b | 652 | |
7dc72b28 | 653 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
654 | |
655 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
656 | if (!priv) { |
657 | error = -ENOMEM; | |
658 | goto out_put_bus; | |
659 | } | |
e5dd1278 GKH |
660 | klist_init(&priv->klist_devices, NULL, NULL); |
661 | priv->driver = drv; | |
662 | drv->p = priv; | |
c8e90d82 GKH |
663 | priv->kobj.kset = bus->p->drivers_kset; |
664 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
665 | "%s", drv->name); | |
dc0afa83 | 666 | if (error) |
07634464 | 667 | goto out_unregister; |
d9fd4d3b | 668 | |
c6f7e72a | 669 | if (drv->bus->p->drivers_autoprobe) { |
b8c5cec2 KS |
670 | error = driver_attach(drv); |
671 | if (error) | |
672 | goto out_unregister; | |
673 | } | |
e5dd1278 | 674 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
d9fd4d3b JG |
675 | module_add_driver(drv->owner, drv); |
676 | ||
7ac1cf4a KS |
677 | error = driver_create_file(drv, &driver_attr_uevent); |
678 | if (error) { | |
679 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
680 | __FUNCTION__, drv->name); | |
681 | } | |
d9fd4d3b JG |
682 | error = driver_add_attrs(bus, drv); |
683 | if (error) { | |
684 | /* How the hell do we get out of this pickle? Give up */ | |
685 | printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", | |
686 | __FUNCTION__, drv->name); | |
687 | } | |
688 | error = add_bind_files(drv); | |
689 | if (error) { | |
690 | /* Ditto */ | |
691 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
692 | __FUNCTION__, drv->name); | |
1da177e4 | 693 | } |
d9fd4d3b | 694 | |
c8e90d82 | 695 | kobject_uevent(&priv->kobj, KOBJ_ADD); |
1da177e4 | 696 | return error; |
f86db396 | 697 | out_unregister: |
c10997f6 | 698 | kobject_put(&priv->kobj); |
f86db396 | 699 | out_put_bus: |
fc1ede58 | 700 | bus_put(bus); |
f86db396 | 701 | return error; |
1da177e4 LT |
702 | } |
703 | ||
1da177e4 | 704 | /** |
4a3ad20c GKH |
705 | * bus_remove_driver - delete driver from bus's knowledge. |
706 | * @drv: driver. | |
1da177e4 | 707 | * |
4a3ad20c GKH |
708 | * Detach the driver from the devices it controls, and remove |
709 | * it from its bus's list of drivers. Finally, we drop the reference | |
710 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 711 | */ |
4a3ad20c | 712 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 713 | { |
d9fd4d3b JG |
714 | if (!drv->bus) |
715 | return; | |
716 | ||
717 | remove_bind_files(drv); | |
718 | driver_remove_attrs(drv->bus, drv); | |
7ac1cf4a | 719 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 720 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 721 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
722 | driver_detach(drv); |
723 | module_remove_driver(drv); | |
c10997f6 | 724 | kobject_put(&drv->p->kobj); |
fc1ede58 | 725 | bus_put(drv->bus); |
1da177e4 LT |
726 | } |
727 | ||
1da177e4 | 728 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 729 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 730 | void *data) |
1da177e4 | 731 | { |
f86db396 AM |
732 | int ret = 0; |
733 | ||
bf74ad5b AS |
734 | if (!dev->driver) { |
735 | if (dev->parent) /* Needed for USB */ | |
736 | down(&dev->parent->sem); | |
f86db396 | 737 | ret = device_attach(dev); |
bf74ad5b AS |
738 | if (dev->parent) |
739 | up(&dev->parent->sem); | |
740 | } | |
f86db396 | 741 | return ret < 0 ? ret : 0; |
1da177e4 LT |
742 | } |
743 | ||
1da177e4 | 744 | /** |
23d3d602 GKH |
745 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
746 | * @bus: the bus to scan. | |
1da177e4 | 747 | * |
23d3d602 GKH |
748 | * This function will look for devices on the bus with no driver |
749 | * attached and rescan it against existing drivers to see if it matches | |
750 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 751 | */ |
4a3ad20c | 752 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 753 | { |
f86db396 | 754 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 755 | } |
4a3ad20c | 756 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 757 | |
e935d5da ME |
758 | /** |
759 | * device_reprobe - remove driver for a device and probe for a new driver | |
760 | * @dev: the device to reprobe | |
761 | * | |
762 | * This function detaches the attached driver (if any) for the given | |
763 | * device and restarts the driver probing process. It is intended | |
764 | * to use if probing criteria changed during a devices lifetime and | |
765 | * driver attachment should change accordingly. | |
766 | */ | |
f86db396 | 767 | int device_reprobe(struct device *dev) |
e935d5da ME |
768 | { |
769 | if (dev->driver) { | |
770 | if (dev->parent) /* Needed for USB */ | |
771 | down(&dev->parent->sem); | |
772 | device_release_driver(dev); | |
773 | if (dev->parent) | |
774 | up(&dev->parent->sem); | |
775 | } | |
f86db396 | 776 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
777 | } |
778 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 779 | |
1da177e4 | 780 | /** |
4a3ad20c GKH |
781 | * find_bus - locate bus by name. |
782 | * @name: name of bus. | |
1da177e4 | 783 | * |
4a3ad20c GKH |
784 | * Call kset_find_obj() to iterate over list of buses to |
785 | * find a bus by name. Return bus if found. | |
1da177e4 | 786 | * |
4a3ad20c | 787 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 788 | */ |
7e4ef085 | 789 | #if 0 |
4a3ad20c | 790 | struct bus_type *find_bus(char *name) |
1da177e4 | 791 | { |
4a3ad20c | 792 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
793 | return k ? to_bus(k) : NULL; |
794 | } | |
7e4ef085 | 795 | #endif /* 0 */ |
1da177e4 LT |
796 | |
797 | ||
798 | /** | |
4a3ad20c GKH |
799 | * bus_add_attrs - Add default attributes for this bus. |
800 | * @bus: Bus that has just been registered. | |
1da177e4 LT |
801 | */ |
802 | ||
4a3ad20c | 803 | static int bus_add_attrs(struct bus_type *bus) |
1da177e4 LT |
804 | { |
805 | int error = 0; | |
806 | int i; | |
807 | ||
808 | if (bus->bus_attrs) { | |
809 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) { | |
4a3ad20c | 810 | error = bus_create_file(bus, &bus->bus_attrs[i]); |
dc0afa83 | 811 | if (error) |
4a3ad20c | 812 | goto err; |
1da177e4 LT |
813 | } |
814 | } | |
4a3ad20c | 815 | done: |
1da177e4 | 816 | return error; |
4a3ad20c | 817 | err: |
1da177e4 | 818 | while (--i >= 0) |
4a3ad20c GKH |
819 | bus_remove_file(bus, &bus->bus_attrs[i]); |
820 | goto done; | |
1da177e4 LT |
821 | } |
822 | ||
4a3ad20c | 823 | static void bus_remove_attrs(struct bus_type *bus) |
1da177e4 LT |
824 | { |
825 | int i; | |
826 | ||
827 | if (bus->bus_attrs) { | |
828 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) | |
4a3ad20c | 829 | bus_remove_file(bus, &bus->bus_attrs[i]); |
1da177e4 LT |
830 | } |
831 | } | |
832 | ||
34bb61f9 JB |
833 | static void klist_devices_get(struct klist_node *n) |
834 | { | |
835 | struct device *dev = container_of(n, struct device, knode_bus); | |
836 | ||
837 | get_device(dev); | |
838 | } | |
839 | ||
840 | static void klist_devices_put(struct klist_node *n) | |
841 | { | |
842 | struct device *dev = container_of(n, struct device, knode_bus); | |
843 | ||
844 | put_device(dev); | |
845 | } | |
846 | ||
7ac1cf4a KS |
847 | static ssize_t bus_uevent_store(struct bus_type *bus, |
848 | const char *buf, size_t count) | |
849 | { | |
850 | enum kobject_action action; | |
851 | ||
852 | if (kobject_action_type(buf, count, &action) == 0) | |
c6f7e72a | 853 | kobject_uevent(&bus->p->subsys.kobj, action); |
7ac1cf4a KS |
854 | return count; |
855 | } | |
856 | static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); | |
857 | ||
1da177e4 | 858 | /** |
4a3ad20c GKH |
859 | * bus_register - register a bus with the system. |
860 | * @bus: bus. | |
1da177e4 | 861 | * |
4a3ad20c GKH |
862 | * Once we have that, we registered the bus with the kobject |
863 | * infrastructure, then register the children subsystems it has: | |
864 | * the devices and drivers that belong to the bus. | |
1da177e4 | 865 | */ |
4a3ad20c | 866 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
867 | { |
868 | int retval; | |
c6f7e72a GKH |
869 | struct bus_type_private *priv; |
870 | ||
871 | priv = kzalloc(sizeof(struct bus_type_private), GFP_KERNEL); | |
872 | if (!priv) | |
873 | return -ENOMEM; | |
874 | ||
875 | priv->bus = bus; | |
876 | bus->p = priv; | |
1da177e4 | 877 | |
c6f7e72a | 878 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 879 | |
c6f7e72a | 880 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
881 | if (retval) |
882 | goto out; | |
883 | ||
c6f7e72a GKH |
884 | priv->subsys.kobj.kset = bus_kset; |
885 | priv->subsys.kobj.ktype = &bus_ktype; | |
886 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 887 | |
c6f7e72a | 888 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
889 | if (retval) |
890 | goto out; | |
891 | ||
7ac1cf4a KS |
892 | retval = bus_create_file(bus, &bus_attr_uevent); |
893 | if (retval) | |
894 | goto bus_uevent_fail; | |
895 | ||
c6f7e72a GKH |
896 | priv->devices_kset = kset_create_and_add("devices", NULL, |
897 | &priv->subsys.kobj); | |
898 | if (!priv->devices_kset) { | |
3d899596 | 899 | retval = -ENOMEM; |
1da177e4 | 900 | goto bus_devices_fail; |
3d899596 | 901 | } |
1da177e4 | 902 | |
c6f7e72a GKH |
903 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
904 | &priv->subsys.kobj); | |
905 | if (!priv->drivers_kset) { | |
6dcec251 | 906 | retval = -ENOMEM; |
1da177e4 | 907 | goto bus_drivers_fail; |
6dcec251 | 908 | } |
465c7a3a | 909 | |
c6f7e72a GKH |
910 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
911 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 912 | |
b8c5cec2 KS |
913 | retval = add_probe_files(bus); |
914 | if (retval) | |
915 | goto bus_probe_files_fail; | |
916 | ||
1bb6881a CH |
917 | retval = bus_add_attrs(bus); |
918 | if (retval) | |
919 | goto bus_attrs_fail; | |
1da177e4 | 920 | |
7dc72b28 | 921 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
922 | return 0; |
923 | ||
1bb6881a | 924 | bus_attrs_fail: |
b8c5cec2 KS |
925 | remove_probe_files(bus); |
926 | bus_probe_files_fail: | |
c6f7e72a | 927 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 928 | bus_drivers_fail: |
c6f7e72a | 929 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 930 | bus_devices_fail: |
7ac1cf4a KS |
931 | bus_remove_file(bus, &bus_attr_uevent); |
932 | bus_uevent_fail: | |
c6f7e72a GKH |
933 | kset_unregister(&bus->p->subsys); |
934 | kfree(bus->p); | |
1da177e4 LT |
935 | out: |
936 | return retval; | |
937 | } | |
4a3ad20c | 938 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 939 | |
1da177e4 | 940 | /** |
4a3ad20c GKH |
941 | * bus_unregister - remove a bus from the system |
942 | * @bus: bus. | |
1da177e4 | 943 | * |
4a3ad20c GKH |
944 | * Unregister the child subsystems and the bus itself. |
945 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 946 | */ |
4a3ad20c | 947 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 948 | { |
7dc72b28 | 949 | pr_debug("bus: '%s': unregistering\n", bus->name); |
1da177e4 | 950 | bus_remove_attrs(bus); |
b8c5cec2 | 951 | remove_probe_files(bus); |
c6f7e72a GKH |
952 | kset_unregister(bus->p->drivers_kset); |
953 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 954 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a GKH |
955 | kset_unregister(&bus->p->subsys); |
956 | kfree(bus->p); | |
1da177e4 | 957 | } |
4a3ad20c | 958 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 959 | |
116af378 BH |
960 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
961 | { | |
c6f7e72a | 962 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
963 | } |
964 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
965 | ||
966 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
967 | { | |
c6f7e72a | 968 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
969 | } |
970 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
971 | ||
0fed80f7 GKH |
972 | struct kset *bus_get_kset(struct bus_type *bus) |
973 | { | |
c6f7e72a | 974 | return &bus->p->subsys; |
0fed80f7 GKH |
975 | } |
976 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
977 | ||
b249072e GKH |
978 | struct klist *bus_get_device_klist(struct bus_type *bus) |
979 | { | |
c6f7e72a | 980 | return &bus->p->klist_devices; |
b249072e GKH |
981 | } |
982 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
983 | ||
1da177e4 LT |
984 | int __init buses_init(void) |
985 | { | |
59a54833 GKH |
986 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
987 | if (!bus_kset) | |
988 | return -ENOMEM; | |
989 | return 0; | |
1da177e4 | 990 | } |