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> | |
ca22e56d | 19 | #include <linux/mutex.h> |
1da177e4 LT |
20 | #include "base.h" |
21 | #include "power/power.h" | |
22 | ||
ca22e56d | 23 | /* /sys/devices/system */ |
97ec448a | 24 | static struct kset *system_kset; |
ca22e56d | 25 | |
1da177e4 | 26 | #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) |
1da177e4 LT |
27 | |
28 | /* | |
29 | * sysfs bindings for drivers | |
30 | */ | |
31 | ||
32 | #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) | |
1da177e4 LT |
33 | |
34 | ||
b8c5cec2 KS |
35 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
36 | void *data); | |
37 | ||
5901d014 GKH |
38 | static struct bus_type *bus_get(struct bus_type *bus) |
39 | { | |
c6f7e72a GKH |
40 | if (bus) { |
41 | kset_get(&bus->p->subsys); | |
42 | return bus; | |
43 | } | |
44 | return NULL; | |
5901d014 GKH |
45 | } |
46 | ||
fc1ede58 GKH |
47 | static void bus_put(struct bus_type *bus) |
48 | { | |
c6f7e72a GKH |
49 | if (bus) |
50 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
51 | } |
52 | ||
4a3ad20c GKH |
53 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
54 | char *buf) | |
1da177e4 | 55 | { |
4a3ad20c | 56 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 57 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 58 | ssize_t ret = -EIO; |
1da177e4 LT |
59 | |
60 | if (drv_attr->show) | |
e5dd1278 | 61 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
62 | return ret; |
63 | } | |
64 | ||
4a3ad20c GKH |
65 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
66 | const char *buf, size_t count) | |
1da177e4 | 67 | { |
4a3ad20c | 68 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 69 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 70 | ssize_t ret = -EIO; |
1da177e4 LT |
71 | |
72 | if (drv_attr->store) | |
e5dd1278 | 73 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
74 | return ret; |
75 | } | |
76 | ||
52cf25d0 | 77 | static const struct sysfs_ops driver_sysfs_ops = { |
1da177e4 LT |
78 | .show = drv_attr_show, |
79 | .store = drv_attr_store, | |
80 | }; | |
81 | ||
e5dd1278 | 82 | static void driver_release(struct kobject *kobj) |
1da177e4 | 83 | { |
e5dd1278 GKH |
84 | struct driver_private *drv_priv = to_driver(kobj); |
85 | ||
2b3a302a | 86 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 87 | kfree(drv_priv); |
1da177e4 LT |
88 | } |
89 | ||
a1148fb0 | 90 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
91 | .sysfs_ops = &driver_sysfs_ops, |
92 | .release = driver_release, | |
93 | }; | |
94 | ||
1da177e4 LT |
95 | /* |
96 | * sysfs bindings for buses | |
97 | */ | |
4a3ad20c GKH |
98 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
99 | char *buf) | |
1da177e4 | 100 | { |
4a3ad20c | 101 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 102 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
103 | ssize_t ret = 0; |
104 | ||
105 | if (bus_attr->show) | |
6b6e39a6 | 106 | ret = bus_attr->show(subsys_priv->bus, buf); |
1da177e4 LT |
107 | return ret; |
108 | } | |
109 | ||
4a3ad20c GKH |
110 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
111 | const char *buf, size_t count) | |
1da177e4 | 112 | { |
4a3ad20c | 113 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 114 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
115 | ssize_t ret = 0; |
116 | ||
117 | if (bus_attr->store) | |
6b6e39a6 | 118 | ret = bus_attr->store(subsys_priv->bus, buf, count); |
1da177e4 LT |
119 | return ret; |
120 | } | |
121 | ||
52cf25d0 | 122 | static const struct sysfs_ops bus_sysfs_ops = { |
1da177e4 LT |
123 | .show = bus_attr_show, |
124 | .store = bus_attr_store, | |
125 | }; | |
126 | ||
4a3ad20c | 127 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
128 | { |
129 | int error; | |
5901d014 | 130 | if (bus_get(bus)) { |
c6f7e72a | 131 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 132 | bus_put(bus); |
1da177e4 LT |
133 | } else |
134 | error = -EINVAL; | |
135 | return error; | |
136 | } | |
4a3ad20c | 137 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 138 | |
4a3ad20c | 139 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 140 | { |
5901d014 | 141 | if (bus_get(bus)) { |
c6f7e72a | 142 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 143 | bus_put(bus); |
1da177e4 LT |
144 | } |
145 | } | |
4a3ad20c | 146 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 147 | |
80f03e34 | 148 | static struct kobj_type bus_ktype = { |
1da177e4 | 149 | .sysfs_ops = &bus_sysfs_ops, |
80f03e34 KS |
150 | }; |
151 | ||
152 | static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) | |
153 | { | |
154 | struct kobj_type *ktype = get_ktype(kobj); | |
155 | ||
156 | if (ktype == &bus_ktype) | |
157 | return 1; | |
158 | return 0; | |
159 | } | |
1da177e4 | 160 | |
9cd43611 | 161 | static const struct kset_uevent_ops bus_uevent_ops = { |
80f03e34 | 162 | .filter = bus_uevent_filter, |
1da177e4 LT |
163 | }; |
164 | ||
59a54833 | 165 | static struct kset *bus_kset; |
1da177e4 | 166 | |
2b08c8d0 | 167 | /* Manually detach a device from its associated driver. */ |
151ef38f GKH |
168 | static ssize_t driver_unbind(struct device_driver *drv, |
169 | const char *buf, size_t count) | |
170 | { | |
5901d014 | 171 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
172 | struct device *dev; |
173 | int err = -ENODEV; | |
174 | ||
1f9ffc04 | 175 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 176 | if (dev && dev->driver == drv) { |
bf74ad5b | 177 | if (dev->parent) /* Needed for USB */ |
8e9394ce | 178 | device_lock(dev->parent); |
151ef38f | 179 | device_release_driver(dev); |
bf74ad5b | 180 | if (dev->parent) |
8e9394ce | 181 | device_unlock(dev->parent); |
151ef38f GKH |
182 | err = count; |
183 | } | |
2b08c8d0 | 184 | put_device(dev); |
fc1ede58 | 185 | bus_put(bus); |
2b08c8d0 | 186 | return err; |
151ef38f GKH |
187 | } |
188 | static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind); | |
189 | ||
afdce75f GKH |
190 | /* |
191 | * Manually attach a device to a driver. | |
192 | * Note: the driver must want to bind to the device, | |
193 | * it is not possible to override the driver's id table. | |
194 | */ | |
195 | static ssize_t driver_bind(struct device_driver *drv, | |
196 | const char *buf, size_t count) | |
197 | { | |
5901d014 | 198 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
199 | struct device *dev; |
200 | int err = -ENODEV; | |
201 | ||
1f9ffc04 | 202 | dev = bus_find_device_by_name(bus, NULL, buf); |
49b420a1 | 203 | if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { |
bf74ad5b | 204 | if (dev->parent) /* Needed for USB */ |
8e9394ce GKH |
205 | device_lock(dev->parent); |
206 | device_lock(dev); | |
afdce75f | 207 | err = driver_probe_device(drv, dev); |
8e9394ce | 208 | device_unlock(dev); |
bf74ad5b | 209 | if (dev->parent) |
8e9394ce | 210 | device_unlock(dev->parent); |
37225401 | 211 | |
4a3ad20c GKH |
212 | if (err > 0) { |
213 | /* success */ | |
37225401 | 214 | err = count; |
4a3ad20c GKH |
215 | } else if (err == 0) { |
216 | /* driver didn't accept device */ | |
37225401 | 217 | err = -ENODEV; |
4a3ad20c | 218 | } |
afdce75f | 219 | } |
2b08c8d0 | 220 | put_device(dev); |
fc1ede58 | 221 | bus_put(bus); |
2b08c8d0 | 222 | return err; |
afdce75f GKH |
223 | } |
224 | static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); | |
225 | ||
b8c5cec2 KS |
226 | static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) |
227 | { | |
c6f7e72a | 228 | return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
229 | } |
230 | ||
231 | static ssize_t store_drivers_autoprobe(struct bus_type *bus, | |
232 | const char *buf, size_t count) | |
233 | { | |
234 | if (buf[0] == '0') | |
c6f7e72a | 235 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 236 | else |
c6f7e72a | 237 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
238 | return count; |
239 | } | |
240 | ||
241 | static ssize_t store_drivers_probe(struct bus_type *bus, | |
242 | const char *buf, size_t count) | |
243 | { | |
244 | struct device *dev; | |
245 | ||
1f9ffc04 | 246 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
247 | if (!dev) |
248 | return -ENODEV; | |
249 | if (bus_rescan_devices_helper(dev, NULL) != 0) | |
250 | return -EINVAL; | |
251 | return count; | |
252 | } | |
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 | 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 | |
4fa3e78b | 293 | if (!bus || !bus->p) |
465c7a3a | 294 | return -EINVAL; |
295 | ||
7cd9c9bb GKH |
296 | klist_iter_init_node(&bus->p->klist_devices, &i, |
297 | (start ? &start->p->knode_bus : NULL)); | |
298 | while ((dev = next_device(&i)) && !error) | |
299 | error = fn(dev, data); | |
300 | klist_iter_exit(&i); | |
465c7a3a | 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 | ||
4fa3e78b | 327 | if (!bus || !bus->p) |
0edb5860 CH |
328 | return NULL; |
329 | ||
7cd9c9bb GKH |
330 | klist_iter_init_node(&bus->p->klist_devices, &i, |
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 | ||
ca22e56d KS |
364 | /** |
365 | * subsys_find_device_by_id - find a device with a specific enumeration number | |
366 | * @subsys: subsystem | |
367 | * @id: index 'id' in struct device | |
368 | * @hint: device to check first | |
369 | * | |
370 | * Check the hint's next object and if it is a match return it directly, | |
371 | * otherwise, fall back to a full list search. Either way a reference for | |
372 | * the returned object is taken. | |
373 | */ | |
374 | struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, | |
375 | struct device *hint) | |
376 | { | |
377 | struct klist_iter i; | |
378 | struct device *dev; | |
379 | ||
380 | if (!subsys) | |
381 | return NULL; | |
382 | ||
383 | if (hint) { | |
7cd9c9bb | 384 | klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); |
ca22e56d KS |
385 | dev = next_device(&i); |
386 | if (dev && dev->id == id && get_device(dev)) { | |
387 | klist_iter_exit(&i); | |
388 | return dev; | |
389 | } | |
390 | klist_iter_exit(&i); | |
391 | } | |
392 | ||
393 | klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); | |
394 | while ((dev = next_device(&i))) { | |
395 | if (dev->id == id && get_device(dev)) { | |
396 | klist_iter_exit(&i); | |
397 | return dev; | |
398 | } | |
399 | } | |
400 | klist_iter_exit(&i); | |
401 | return NULL; | |
402 | } | |
403 | EXPORT_SYMBOL_GPL(subsys_find_device_by_id); | |
404 | ||
4a3ad20c | 405 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 406 | { |
4a3ad20c | 407 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
408 | struct driver_private *drv_priv; |
409 | ||
410 | if (n) { | |
411 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
412 | return drv_priv->driver; | |
413 | } | |
414 | return NULL; | |
38fdac3c | 415 | } |
416 | ||
1da177e4 | 417 | /** |
4a3ad20c GKH |
418 | * bus_for_each_drv - driver iterator |
419 | * @bus: bus we're dealing with. | |
420 | * @start: driver to start iterating on. | |
421 | * @data: data to pass to the callback. | |
422 | * @fn: function to call for each driver. | |
1da177e4 | 423 | * |
4a3ad20c GKH |
424 | * This is nearly identical to the device iterator above. |
425 | * We iterate over each driver that belongs to @bus, and call | |
426 | * @fn for each. If @fn returns anything but 0, we break out | |
427 | * and return it. If @start is not NULL, we use it as the head | |
428 | * of the list. | |
1da177e4 | 429 | * |
4a3ad20c GKH |
430 | * NOTE: we don't return the driver that returns a non-zero |
431 | * value, nor do we leave the reference count incremented for that | |
432 | * driver. If the caller needs to know that info, it must set it | |
433 | * in the callback. It must also be sure to increment the refcount | |
434 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 435 | */ |
4a3ad20c GKH |
436 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
437 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 438 | { |
38fdac3c | 439 | struct klist_iter i; |
4a3ad20c | 440 | struct device_driver *drv; |
38fdac3c | 441 | int error = 0; |
1da177e4 | 442 | |
38fdac3c | 443 | if (!bus) |
444 | return -EINVAL; | |
445 | ||
7cd9c9bb GKH |
446 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
447 | start ? &start->p->knode_bus : NULL); | |
448 | while ((drv = next_driver(&i)) && !error) | |
449 | error = fn(drv, data); | |
450 | klist_iter_exit(&i); | |
38fdac3c | 451 | return error; |
1da177e4 | 452 | } |
4a3ad20c | 453 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 454 | |
4aca67e5 | 455 | static int device_add_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
456 | { |
457 | int error = 0; | |
458 | int i; | |
459 | ||
4aca67e5 AM |
460 | if (!bus->dev_attrs) |
461 | return 0; | |
462 | ||
463 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) { | |
4a3ad20c | 464 | error = device_create_file(dev, &bus->dev_attrs[i]); |
4aca67e5 AM |
465 | if (error) { |
466 | while (--i >= 0) | |
467 | device_remove_file(dev, &bus->dev_attrs[i]); | |
468 | break; | |
1da177e4 LT |
469 | } |
470 | } | |
1da177e4 | 471 | return error; |
1da177e4 LT |
472 | } |
473 | ||
4a3ad20c | 474 | static void device_remove_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
475 | { |
476 | int i; | |
477 | ||
478 | if (bus->dev_attrs) { | |
479 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) | |
4a3ad20c | 480 | device_remove_file(dev, &bus->dev_attrs[i]); |
1da177e4 LT |
481 | } |
482 | } | |
483 | ||
1da177e4 | 484 | /** |
4a3ad20c GKH |
485 | * bus_add_device - add device to bus |
486 | * @dev: device being added | |
1da177e4 | 487 | * |
2023c610 AS |
488 | * - Add device's bus attributes. |
489 | * - Create links to device's bus. | |
4a3ad20c | 490 | * - Add the device to its bus's list of devices. |
1da177e4 | 491 | */ |
4a3ad20c | 492 | int bus_add_device(struct device *dev) |
1da177e4 | 493 | { |
4a3ad20c | 494 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
495 | int error = 0; |
496 | ||
497 | if (bus) { | |
1e0b2cf9 | 498 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
d377e85b | 499 | error = device_add_attrs(bus, dev); |
f86db396 | 500 | if (error) |
513e7337 | 501 | goto out_put; |
fa6fdb33 GKH |
502 | error = device_add_groups(dev, bus->dev_groups); |
503 | if (error) | |
504 | goto out_groups; | |
c6f7e72a | 505 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 506 | &dev->kobj, dev_name(dev)); |
f86db396 | 507 | if (error) |
513e7337 | 508 | goto out_id; |
f86db396 | 509 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 510 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 511 | if (error) |
513e7337 | 512 | goto out_subsys; |
2023c610 | 513 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 514 | } |
513e7337 CH |
515 | return 0; |
516 | ||
513e7337 | 517 | out_subsys: |
1e0b2cf9 | 518 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
fa6fdb33 GKH |
519 | out_groups: |
520 | device_remove_groups(dev, bus->dev_groups); | |
513e7337 CH |
521 | out_id: |
522 | device_remove_attrs(bus, dev); | |
523 | out_put: | |
fc1ede58 | 524 | bus_put(dev->bus); |
1da177e4 LT |
525 | return error; |
526 | } | |
527 | ||
53877d06 | 528 | /** |
2023c610 AS |
529 | * bus_probe_device - probe drivers for a new device |
530 | * @dev: device to probe | |
53877d06 | 531 | * |
2023c610 | 532 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 533 | */ |
2023c610 | 534 | void bus_probe_device(struct device *dev) |
53877d06 | 535 | { |
f86db396 | 536 | struct bus_type *bus = dev->bus; |
ca22e56d | 537 | struct subsys_interface *sif; |
2023c610 | 538 | int ret; |
53877d06 | 539 | |
ca22e56d KS |
540 | if (!bus) |
541 | return; | |
542 | ||
543 | if (bus->p->drivers_autoprobe) { | |
2023c610 | 544 | ret = device_attach(dev); |
c6a46696 | 545 | WARN_ON(ret < 0); |
53877d06 | 546 | } |
ca22e56d KS |
547 | |
548 | mutex_lock(&bus->p->mutex); | |
549 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
550 | if (sif->add_dev) | |
551 | sif->add_dev(dev, sif); | |
552 | mutex_unlock(&bus->p->mutex); | |
53877d06 KS |
553 | } |
554 | ||
1da177e4 | 555 | /** |
4a3ad20c GKH |
556 | * bus_remove_device - remove device from bus |
557 | * @dev: device to be removed | |
1da177e4 | 558 | * |
ca22e56d KS |
559 | * - Remove device from all interfaces. |
560 | * - Remove symlink from bus' directory. | |
4a3ad20c GKH |
561 | * - Delete device from bus's list. |
562 | * - Detach from its driver. | |
563 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 564 | */ |
4a3ad20c | 565 | void bus_remove_device(struct device *dev) |
1da177e4 | 566 | { |
ca22e56d KS |
567 | struct bus_type *bus = dev->bus; |
568 | struct subsys_interface *sif; | |
569 | ||
570 | if (!bus) | |
571 | return; | |
572 | ||
573 | mutex_lock(&bus->p->mutex); | |
574 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
575 | if (sif->remove_dev) | |
576 | sif->remove_dev(dev, sif); | |
577 | mutex_unlock(&bus->p->mutex); | |
578 | ||
579 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
580 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, | |
581 | dev_name(dev)); | |
582 | device_remove_attrs(dev->bus, dev); | |
fa6fdb33 | 583 | device_remove_groups(dev, dev->bus->dev_groups); |
ca22e56d KS |
584 | if (klist_node_attached(&dev->p->knode_bus)) |
585 | klist_del(&dev->p->knode_bus); | |
586 | ||
587 | pr_debug("bus: '%s': remove device %s\n", | |
588 | dev->bus->name, dev_name(dev)); | |
589 | device_release_driver(dev); | |
590 | bus_put(dev->bus); | |
1da177e4 LT |
591 | } |
592 | ||
4a3ad20c | 593 | static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv) |
1da177e4 LT |
594 | { |
595 | int error = 0; | |
596 | int i; | |
597 | ||
598 | if (bus->drv_attrs) { | |
599 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) { | |
600 | error = driver_create_file(drv, &bus->drv_attrs[i]); | |
601 | if (error) | |
4a3ad20c | 602 | goto err; |
1da177e4 LT |
603 | } |
604 | } | |
4a3ad20c | 605 | done: |
1da177e4 | 606 | return error; |
4a3ad20c | 607 | err: |
1da177e4 LT |
608 | while (--i >= 0) |
609 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
4a3ad20c | 610 | goto done; |
1da177e4 LT |
611 | } |
612 | ||
4a3ad20c GKH |
613 | static void driver_remove_attrs(struct bus_type *bus, |
614 | struct device_driver *drv) | |
1da177e4 LT |
615 | { |
616 | int i; | |
617 | ||
618 | if (bus->drv_attrs) { | |
619 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) | |
620 | driver_remove_file(drv, &bus->drv_attrs[i]); | |
621 | } | |
622 | } | |
623 | ||
f86db396 | 624 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 625 | { |
f86db396 AM |
626 | int ret; |
627 | ||
628 | ret = driver_create_file(drv, &driver_attr_unbind); | |
629 | if (ret == 0) { | |
630 | ret = driver_create_file(drv, &driver_attr_bind); | |
631 | if (ret) | |
632 | driver_remove_file(drv, &driver_attr_unbind); | |
633 | } | |
634 | return ret; | |
874c6241 GKH |
635 | } |
636 | ||
637 | static void remove_bind_files(struct device_driver *drv) | |
638 | { | |
639 | driver_remove_file(drv, &driver_attr_bind); | |
640 | driver_remove_file(drv, &driver_attr_unbind); | |
641 | } | |
b8c5cec2 | 642 | |
8380770c KS |
643 | static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); |
644 | static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, | |
645 | show_drivers_autoprobe, store_drivers_autoprobe); | |
646 | ||
b8c5cec2 KS |
647 | static int add_probe_files(struct bus_type *bus) |
648 | { | |
649 | int retval; | |
650 | ||
8380770c | 651 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
652 | if (retval) |
653 | goto out; | |
654 | ||
8380770c | 655 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 656 | if (retval) |
8380770c | 657 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
658 | out: |
659 | return retval; | |
660 | } | |
661 | ||
662 | static void remove_probe_files(struct bus_type *bus) | |
663 | { | |
8380770c KS |
664 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
665 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 666 | } |
1da177e4 | 667 | |
7ac1cf4a KS |
668 | static ssize_t driver_uevent_store(struct device_driver *drv, |
669 | const char *buf, size_t count) | |
670 | { | |
671 | enum kobject_action action; | |
672 | ||
673 | if (kobject_action_type(buf, count, &action) == 0) | |
e5dd1278 | 674 | kobject_uevent(&drv->p->kobj, action); |
7ac1cf4a KS |
675 | return count; |
676 | } | |
677 | static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store); | |
678 | ||
1da177e4 | 679 | /** |
4a3ad20c GKH |
680 | * bus_add_driver - Add a driver to the bus. |
681 | * @drv: driver. | |
1da177e4 | 682 | */ |
f86db396 | 683 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 684 | { |
e5dd1278 GKH |
685 | struct bus_type *bus; |
686 | struct driver_private *priv; | |
1da177e4 LT |
687 | int error = 0; |
688 | ||
e5dd1278 | 689 | bus = bus_get(drv->bus); |
d9fd4d3b | 690 | if (!bus) |
4f6e1945 | 691 | return -EINVAL; |
d9fd4d3b | 692 | |
7dc72b28 | 693 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
694 | |
695 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
696 | if (!priv) { |
697 | error = -ENOMEM; | |
698 | goto out_put_bus; | |
699 | } | |
e5dd1278 GKH |
700 | klist_init(&priv->klist_devices, NULL, NULL); |
701 | priv->driver = drv; | |
702 | drv->p = priv; | |
c8e90d82 GKH |
703 | priv->kobj.kset = bus->p->drivers_kset; |
704 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
705 | "%s", drv->name); | |
dc0afa83 | 706 | if (error) |
07634464 | 707 | goto out_unregister; |
d9fd4d3b | 708 | |
190888ac | 709 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
c6f7e72a | 710 | if (drv->bus->p->drivers_autoprobe) { |
b8c5cec2 KS |
711 | error = driver_attach(drv); |
712 | if (error) | |
713 | goto out_unregister; | |
714 | } | |
d9fd4d3b JG |
715 | module_add_driver(drv->owner, drv); |
716 | ||
7ac1cf4a KS |
717 | error = driver_create_file(drv, &driver_attr_uevent); |
718 | if (error) { | |
719 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 720 | __func__, drv->name); |
7ac1cf4a | 721 | } |
d9fd4d3b JG |
722 | error = driver_add_attrs(bus, drv); |
723 | if (error) { | |
724 | /* How the hell do we get out of this pickle? Give up */ | |
725 | printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", | |
2b3a302a | 726 | __func__, drv->name); |
d9fd4d3b | 727 | } |
ed0617b5 GKH |
728 | error = driver_add_groups(drv, bus->drv_groups); |
729 | if (error) | |
730 | printk(KERN_ERR "%s: driver_create_groups(%s) failed\n", | |
731 | __func__, drv->name); | |
1a6f2a75 DT |
732 | |
733 | if (!drv->suppress_bind_attrs) { | |
734 | error = add_bind_files(drv); | |
735 | if (error) { | |
736 | /* Ditto */ | |
737 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
738 | __func__, drv->name); | |
739 | } | |
1da177e4 | 740 | } |
d9fd4d3b | 741 | |
5c8563d7 | 742 | return 0; |
1a6f2a75 | 743 | |
f86db396 | 744 | out_unregister: |
99b28f1b | 745 | kobject_put(&priv->kobj); |
5c8563d7 KS |
746 | kfree(drv->p); |
747 | drv->p = NULL; | |
f86db396 | 748 | out_put_bus: |
fc1ede58 | 749 | bus_put(bus); |
f86db396 | 750 | return error; |
1da177e4 LT |
751 | } |
752 | ||
1da177e4 | 753 | /** |
4a3ad20c GKH |
754 | * bus_remove_driver - delete driver from bus's knowledge. |
755 | * @drv: driver. | |
1da177e4 | 756 | * |
4a3ad20c GKH |
757 | * Detach the driver from the devices it controls, and remove |
758 | * it from its bus's list of drivers. Finally, we drop the reference | |
759 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 760 | */ |
4a3ad20c | 761 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 762 | { |
d9fd4d3b JG |
763 | if (!drv->bus) |
764 | return; | |
765 | ||
1a6f2a75 DT |
766 | if (!drv->suppress_bind_attrs) |
767 | remove_bind_files(drv); | |
d9fd4d3b | 768 | driver_remove_attrs(drv->bus, drv); |
ed0617b5 | 769 | driver_remove_groups(drv, drv->bus->drv_groups); |
7ac1cf4a | 770 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 771 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 772 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
773 | driver_detach(drv); |
774 | module_remove_driver(drv); | |
c10997f6 | 775 | kobject_put(&drv->p->kobj); |
fc1ede58 | 776 | bus_put(drv->bus); |
1da177e4 LT |
777 | } |
778 | ||
1da177e4 | 779 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 780 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 781 | void *data) |
1da177e4 | 782 | { |
f86db396 AM |
783 | int ret = 0; |
784 | ||
bf74ad5b AS |
785 | if (!dev->driver) { |
786 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 787 | device_lock(dev->parent); |
f86db396 | 788 | ret = device_attach(dev); |
bf74ad5b | 789 | if (dev->parent) |
8e9394ce | 790 | device_unlock(dev->parent); |
bf74ad5b | 791 | } |
f86db396 | 792 | return ret < 0 ? ret : 0; |
1da177e4 LT |
793 | } |
794 | ||
1da177e4 | 795 | /** |
23d3d602 GKH |
796 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
797 | * @bus: the bus to scan. | |
1da177e4 | 798 | * |
23d3d602 GKH |
799 | * This function will look for devices on the bus with no driver |
800 | * attached and rescan it against existing drivers to see if it matches | |
801 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 802 | */ |
4a3ad20c | 803 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 804 | { |
f86db396 | 805 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 806 | } |
4a3ad20c | 807 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 808 | |
e935d5da ME |
809 | /** |
810 | * device_reprobe - remove driver for a device and probe for a new driver | |
811 | * @dev: the device to reprobe | |
812 | * | |
813 | * This function detaches the attached driver (if any) for the given | |
814 | * device and restarts the driver probing process. It is intended | |
815 | * to use if probing criteria changed during a devices lifetime and | |
816 | * driver attachment should change accordingly. | |
817 | */ | |
f86db396 | 818 | int device_reprobe(struct device *dev) |
e935d5da ME |
819 | { |
820 | if (dev->driver) { | |
821 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 822 | device_lock(dev->parent); |
e935d5da ME |
823 | device_release_driver(dev); |
824 | if (dev->parent) | |
8e9394ce | 825 | device_unlock(dev->parent); |
e935d5da | 826 | } |
f86db396 | 827 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
828 | } |
829 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 830 | |
1da177e4 | 831 | /** |
4a3ad20c GKH |
832 | * find_bus - locate bus by name. |
833 | * @name: name of bus. | |
1da177e4 | 834 | * |
4a3ad20c GKH |
835 | * Call kset_find_obj() to iterate over list of buses to |
836 | * find a bus by name. Return bus if found. | |
1da177e4 | 837 | * |
4a3ad20c | 838 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 839 | */ |
7e4ef085 | 840 | #if 0 |
4a3ad20c | 841 | struct bus_type *find_bus(char *name) |
1da177e4 | 842 | { |
4a3ad20c | 843 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
844 | return k ? to_bus(k) : NULL; |
845 | } | |
7e4ef085 | 846 | #endif /* 0 */ |
1da177e4 LT |
847 | |
848 | ||
849 | /** | |
4a3ad20c GKH |
850 | * bus_add_attrs - Add default attributes for this bus. |
851 | * @bus: Bus that has just been registered. | |
1da177e4 LT |
852 | */ |
853 | ||
4a3ad20c | 854 | static int bus_add_attrs(struct bus_type *bus) |
1da177e4 LT |
855 | { |
856 | int error = 0; | |
857 | int i; | |
858 | ||
859 | if (bus->bus_attrs) { | |
860 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) { | |
4a3ad20c | 861 | error = bus_create_file(bus, &bus->bus_attrs[i]); |
dc0afa83 | 862 | if (error) |
4a3ad20c | 863 | goto err; |
1da177e4 LT |
864 | } |
865 | } | |
4a3ad20c | 866 | done: |
1da177e4 | 867 | return error; |
4a3ad20c | 868 | err: |
1da177e4 | 869 | while (--i >= 0) |
4a3ad20c GKH |
870 | bus_remove_file(bus, &bus->bus_attrs[i]); |
871 | goto done; | |
1da177e4 LT |
872 | } |
873 | ||
4a3ad20c | 874 | static void bus_remove_attrs(struct bus_type *bus) |
1da177e4 LT |
875 | { |
876 | int i; | |
877 | ||
878 | if (bus->bus_attrs) { | |
879 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) | |
4a3ad20c | 880 | bus_remove_file(bus, &bus->bus_attrs[i]); |
1da177e4 LT |
881 | } |
882 | } | |
883 | ||
12478ba0 GKH |
884 | static int bus_add_groups(struct bus_type *bus, |
885 | const struct attribute_group **groups) | |
886 | { | |
3e9b2bae | 887 | return sysfs_create_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
888 | } |
889 | ||
890 | static void bus_remove_groups(struct bus_type *bus, | |
891 | const struct attribute_group **groups) | |
892 | { | |
3e9b2bae | 893 | sysfs_remove_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
894 | } |
895 | ||
34bb61f9 JB |
896 | static void klist_devices_get(struct klist_node *n) |
897 | { | |
ae1b4171 GKH |
898 | struct device_private *dev_prv = to_device_private_bus(n); |
899 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
900 | |
901 | get_device(dev); | |
902 | } | |
903 | ||
904 | static void klist_devices_put(struct klist_node *n) | |
905 | { | |
ae1b4171 GKH |
906 | struct device_private *dev_prv = to_device_private_bus(n); |
907 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
908 | |
909 | put_device(dev); | |
910 | } | |
911 | ||
7ac1cf4a KS |
912 | static ssize_t bus_uevent_store(struct bus_type *bus, |
913 | const char *buf, size_t count) | |
914 | { | |
915 | enum kobject_action action; | |
916 | ||
917 | if (kobject_action_type(buf, count, &action) == 0) | |
c6f7e72a | 918 | kobject_uevent(&bus->p->subsys.kobj, action); |
7ac1cf4a KS |
919 | return count; |
920 | } | |
921 | static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); | |
922 | ||
1da177e4 | 923 | /** |
be871b7e | 924 | * bus_register - register a driver-core subsystem |
78d79559 | 925 | * @bus: bus to register |
1da177e4 | 926 | * |
78d79559 | 927 | * Once we have that, we register the bus with the kobject |
4a3ad20c | 928 | * infrastructure, then register the children subsystems it has: |
ca22e56d | 929 | * the devices and drivers that belong to the subsystem. |
1da177e4 | 930 | */ |
be871b7e | 931 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
932 | { |
933 | int retval; | |
6b6e39a6 | 934 | struct subsys_private *priv; |
be871b7e | 935 | struct lock_class_key *key = &bus->lock_key; |
c6f7e72a | 936 | |
6b6e39a6 | 937 | priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL); |
c6f7e72a GKH |
938 | if (!priv) |
939 | return -ENOMEM; | |
940 | ||
941 | priv->bus = bus; | |
942 | bus->p = priv; | |
1da177e4 | 943 | |
c6f7e72a | 944 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 945 | |
c6f7e72a | 946 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
947 | if (retval) |
948 | goto out; | |
949 | ||
c6f7e72a GKH |
950 | priv->subsys.kobj.kset = bus_kset; |
951 | priv->subsys.kobj.ktype = &bus_ktype; | |
952 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 953 | |
c6f7e72a | 954 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
955 | if (retval) |
956 | goto out; | |
957 | ||
7ac1cf4a KS |
958 | retval = bus_create_file(bus, &bus_attr_uevent); |
959 | if (retval) | |
960 | goto bus_uevent_fail; | |
961 | ||
c6f7e72a GKH |
962 | priv->devices_kset = kset_create_and_add("devices", NULL, |
963 | &priv->subsys.kobj); | |
964 | if (!priv->devices_kset) { | |
3d899596 | 965 | retval = -ENOMEM; |
1da177e4 | 966 | goto bus_devices_fail; |
3d899596 | 967 | } |
1da177e4 | 968 | |
c6f7e72a GKH |
969 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
970 | &priv->subsys.kobj); | |
971 | if (!priv->drivers_kset) { | |
6dcec251 | 972 | retval = -ENOMEM; |
1da177e4 | 973 | goto bus_drivers_fail; |
6dcec251 | 974 | } |
465c7a3a | 975 | |
ca22e56d KS |
976 | INIT_LIST_HEAD(&priv->interfaces); |
977 | __mutex_init(&priv->mutex, "subsys mutex", key); | |
c6f7e72a GKH |
978 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
979 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 980 | |
b8c5cec2 KS |
981 | retval = add_probe_files(bus); |
982 | if (retval) | |
983 | goto bus_probe_files_fail; | |
984 | ||
1bb6881a CH |
985 | retval = bus_add_attrs(bus); |
986 | if (retval) | |
987 | goto bus_attrs_fail; | |
12478ba0 GKH |
988 | retval = bus_add_groups(bus, bus->bus_groups); |
989 | if (retval) | |
990 | goto bus_groups_fail; | |
1da177e4 | 991 | |
7dc72b28 | 992 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
993 | return 0; |
994 | ||
12478ba0 GKH |
995 | bus_groups_fail: |
996 | bus_remove_attrs(bus); | |
1bb6881a | 997 | bus_attrs_fail: |
b8c5cec2 KS |
998 | remove_probe_files(bus); |
999 | bus_probe_files_fail: | |
c6f7e72a | 1000 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 1001 | bus_drivers_fail: |
c6f7e72a | 1002 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 1003 | bus_devices_fail: |
7ac1cf4a KS |
1004 | bus_remove_file(bus, &bus_attr_uevent); |
1005 | bus_uevent_fail: | |
c6f7e72a | 1006 | kset_unregister(&bus->p->subsys); |
1da177e4 | 1007 | out: |
600c20f3 | 1008 | kfree(bus->p); |
f48f3feb | 1009 | bus->p = NULL; |
1da177e4 LT |
1010 | return retval; |
1011 | } | |
be871b7e | 1012 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 1013 | |
1da177e4 | 1014 | /** |
4a3ad20c GKH |
1015 | * bus_unregister - remove a bus from the system |
1016 | * @bus: bus. | |
1da177e4 | 1017 | * |
4a3ad20c GKH |
1018 | * Unregister the child subsystems and the bus itself. |
1019 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 1020 | */ |
4a3ad20c | 1021 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 1022 | { |
7dc72b28 | 1023 | pr_debug("bus: '%s': unregistering\n", bus->name); |
ca22e56d KS |
1024 | if (bus->dev_root) |
1025 | device_unregister(bus->dev_root); | |
1da177e4 | 1026 | bus_remove_attrs(bus); |
12478ba0 | 1027 | bus_remove_groups(bus, bus->bus_groups); |
b8c5cec2 | 1028 | remove_probe_files(bus); |
c6f7e72a GKH |
1029 | kset_unregister(bus->p->drivers_kset); |
1030 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 1031 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a GKH |
1032 | kset_unregister(&bus->p->subsys); |
1033 | kfree(bus->p); | |
f48f3feb | 1034 | bus->p = NULL; |
1da177e4 | 1035 | } |
4a3ad20c | 1036 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 1037 | |
116af378 BH |
1038 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
1039 | { | |
c6f7e72a | 1040 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
1041 | } |
1042 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
1043 | ||
1044 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
1045 | { | |
c6f7e72a | 1046 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
1047 | } |
1048 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
1049 | ||
0fed80f7 GKH |
1050 | struct kset *bus_get_kset(struct bus_type *bus) |
1051 | { | |
c6f7e72a | 1052 | return &bus->p->subsys; |
0fed80f7 GKH |
1053 | } |
1054 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
1055 | ||
b249072e GKH |
1056 | struct klist *bus_get_device_klist(struct bus_type *bus) |
1057 | { | |
c6f7e72a | 1058 | return &bus->p->klist_devices; |
b249072e GKH |
1059 | } |
1060 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
1061 | ||
99178b03 | 1062 | /* |
dca25ebd | 1063 | * Yes, this forcibly breaks the klist abstraction temporarily. It |
99178b03 GKH |
1064 | * just wants to sort the klist, not change reference counts and |
1065 | * take/drop locks rapidly in the process. It does all this while | |
1066 | * holding the lock for the list, so objects can't otherwise be | |
1067 | * added/removed while we're swizzling. | |
1068 | */ | |
1069 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
1070 | int (*compare)(const struct device *a, | |
1071 | const struct device *b)) | |
1072 | { | |
1073 | struct list_head *pos; | |
1074 | struct klist_node *n; | |
ae1b4171 | 1075 | struct device_private *dev_prv; |
99178b03 GKH |
1076 | struct device *b; |
1077 | ||
1078 | list_for_each(pos, list) { | |
1079 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1080 | dev_prv = to_device_private_bus(n); |
1081 | b = dev_prv->device; | |
99178b03 | 1082 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
1083 | list_move_tail(&a->p->knode_bus.n_node, |
1084 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
1085 | return; |
1086 | } | |
1087 | } | |
ae1b4171 | 1088 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
1089 | } |
1090 | ||
1091 | void bus_sort_breadthfirst(struct bus_type *bus, | |
1092 | int (*compare)(const struct device *a, | |
1093 | const struct device *b)) | |
1094 | { | |
1095 | LIST_HEAD(sorted_devices); | |
1096 | struct list_head *pos, *tmp; | |
1097 | struct klist_node *n; | |
ae1b4171 | 1098 | struct device_private *dev_prv; |
99178b03 GKH |
1099 | struct device *dev; |
1100 | struct klist *device_klist; | |
1101 | ||
1102 | device_klist = bus_get_device_klist(bus); | |
1103 | ||
1104 | spin_lock(&device_klist->k_lock); | |
1105 | list_for_each_safe(pos, tmp, &device_klist->k_list) { | |
1106 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1107 | dev_prv = to_device_private_bus(n); |
1108 | dev = dev_prv->device; | |
99178b03 GKH |
1109 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
1110 | } | |
1111 | list_splice(&sorted_devices, &device_klist->k_list); | |
1112 | spin_unlock(&device_klist->k_lock); | |
1113 | } | |
1114 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
1115 | ||
ca22e56d KS |
1116 | /** |
1117 | * subsys_dev_iter_init - initialize subsys device iterator | |
1118 | * @iter: subsys iterator to initialize | |
1119 | * @subsys: the subsys we wanna iterate over | |
1120 | * @start: the device to start iterating from, if any | |
1121 | * @type: device_type of the devices to iterate over, NULL for all | |
1122 | * | |
1123 | * Initialize subsys iterator @iter such that it iterates over devices | |
1124 | * of @subsys. If @start is set, the list iteration will start there, | |
1125 | * otherwise if it is NULL, the iteration starts at the beginning of | |
1126 | * the list. | |
1127 | */ | |
7cd9c9bb GKH |
1128 | void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys, |
1129 | struct device *start, const struct device_type *type) | |
ca22e56d KS |
1130 | { |
1131 | struct klist_node *start_knode = NULL; | |
1132 | ||
1133 | if (start) | |
1134 | start_knode = &start->p->knode_bus; | |
7cd9c9bb GKH |
1135 | klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode); |
1136 | iter->type = type; | |
ca22e56d KS |
1137 | } |
1138 | EXPORT_SYMBOL_GPL(subsys_dev_iter_init); | |
1139 | ||
1140 | /** | |
1141 | * subsys_dev_iter_next - iterate to the next device | |
1142 | * @iter: subsys iterator to proceed | |
1143 | * | |
1144 | * Proceed @iter to the next device and return it. Returns NULL if | |
1145 | * iteration is complete. | |
1146 | * | |
1147 | * The returned device is referenced and won't be released till | |
1148 | * iterator is proceed to the next device or exited. The caller is | |
1149 | * free to do whatever it wants to do with the device including | |
1150 | * calling back into subsys code. | |
1151 | */ | |
1152 | struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter) | |
1153 | { | |
1154 | struct klist_node *knode; | |
1155 | struct device *dev; | |
1156 | ||
1157 | for (;;) { | |
1158 | knode = klist_next(&iter->ki); | |
1159 | if (!knode) | |
1160 | return NULL; | |
1161 | dev = container_of(knode, struct device_private, knode_bus)->device; | |
1162 | if (!iter->type || iter->type == dev->type) | |
1163 | return dev; | |
1164 | } | |
1165 | } | |
1166 | EXPORT_SYMBOL_GPL(subsys_dev_iter_next); | |
1167 | ||
1168 | /** | |
1169 | * subsys_dev_iter_exit - finish iteration | |
1170 | * @iter: subsys iterator to finish | |
1171 | * | |
1172 | * Finish an iteration. Always call this function after iteration is | |
1173 | * complete whether the iteration ran till the end or not. | |
1174 | */ | |
1175 | void subsys_dev_iter_exit(struct subsys_dev_iter *iter) | |
1176 | { | |
1177 | klist_iter_exit(&iter->ki); | |
1178 | } | |
1179 | EXPORT_SYMBOL_GPL(subsys_dev_iter_exit); | |
1180 | ||
1181 | int subsys_interface_register(struct subsys_interface *sif) | |
1182 | { | |
1183 | struct bus_type *subsys; | |
1184 | struct subsys_dev_iter iter; | |
1185 | struct device *dev; | |
1186 | ||
1187 | if (!sif || !sif->subsys) | |
1188 | return -ENODEV; | |
1189 | ||
1190 | subsys = bus_get(sif->subsys); | |
1191 | if (!subsys) | |
1192 | return -EINVAL; | |
1193 | ||
1194 | mutex_lock(&subsys->p->mutex); | |
1195 | list_add_tail(&sif->node, &subsys->p->interfaces); | |
1196 | if (sif->add_dev) { | |
1197 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1198 | while ((dev = subsys_dev_iter_next(&iter))) | |
1199 | sif->add_dev(dev, sif); | |
1200 | subsys_dev_iter_exit(&iter); | |
1201 | } | |
1202 | mutex_unlock(&subsys->p->mutex); | |
1203 | ||
1204 | return 0; | |
1205 | } | |
1206 | EXPORT_SYMBOL_GPL(subsys_interface_register); | |
1207 | ||
1208 | void subsys_interface_unregister(struct subsys_interface *sif) | |
1209 | { | |
2b31594a | 1210 | struct bus_type *subsys; |
ca22e56d KS |
1211 | struct subsys_dev_iter iter; |
1212 | struct device *dev; | |
1213 | ||
2b31594a | 1214 | if (!sif || !sif->subsys) |
ca22e56d KS |
1215 | return; |
1216 | ||
2b31594a JC |
1217 | subsys = sif->subsys; |
1218 | ||
ca22e56d KS |
1219 | mutex_lock(&subsys->p->mutex); |
1220 | list_del_init(&sif->node); | |
1221 | if (sif->remove_dev) { | |
1222 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1223 | while ((dev = subsys_dev_iter_next(&iter))) | |
1224 | sif->remove_dev(dev, sif); | |
1225 | subsys_dev_iter_exit(&iter); | |
1226 | } | |
1227 | mutex_unlock(&subsys->p->mutex); | |
1228 | ||
1229 | bus_put(subsys); | |
1230 | } | |
1231 | EXPORT_SYMBOL_GPL(subsys_interface_unregister); | |
1232 | ||
1233 | static void system_root_device_release(struct device *dev) | |
1234 | { | |
1235 | kfree(dev); | |
1236 | } | |
d73ce004 TH |
1237 | |
1238 | static int subsys_register(struct bus_type *subsys, | |
1239 | const struct attribute_group **groups, | |
1240 | struct kobject *parent_of_root) | |
ca22e56d KS |
1241 | { |
1242 | struct device *dev; | |
1243 | int err; | |
1244 | ||
1245 | err = bus_register(subsys); | |
1246 | if (err < 0) | |
1247 | return err; | |
1248 | ||
1249 | dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
1250 | if (!dev) { | |
1251 | err = -ENOMEM; | |
1252 | goto err_dev; | |
1253 | } | |
1254 | ||
1255 | err = dev_set_name(dev, "%s", subsys->name); | |
1256 | if (err < 0) | |
1257 | goto err_name; | |
1258 | ||
d73ce004 | 1259 | dev->kobj.parent = parent_of_root; |
ca22e56d KS |
1260 | dev->groups = groups; |
1261 | dev->release = system_root_device_release; | |
1262 | ||
1263 | err = device_register(dev); | |
1264 | if (err < 0) | |
1265 | goto err_dev_reg; | |
1266 | ||
1267 | subsys->dev_root = dev; | |
1268 | return 0; | |
1269 | ||
1270 | err_dev_reg: | |
1271 | put_device(dev); | |
1272 | dev = NULL; | |
1273 | err_name: | |
1274 | kfree(dev); | |
1275 | err_dev: | |
1276 | bus_unregister(subsys); | |
1277 | return err; | |
1278 | } | |
d73ce004 TH |
1279 | |
1280 | /** | |
1281 | * subsys_system_register - register a subsystem at /sys/devices/system/ | |
1282 | * @subsys: system subsystem | |
1283 | * @groups: default attributes for the root device | |
1284 | * | |
1285 | * All 'system' subsystems have a /sys/devices/system/<name> root device | |
1286 | * with the name of the subsystem. The root device can carry subsystem- | |
1287 | * wide attributes. All registered devices are below this single root | |
1288 | * device and are named after the subsystem with a simple enumeration | |
1289 | * number appended. The registered devices are not explicitely named; | |
1290 | * only 'id' in the device needs to be set. | |
1291 | * | |
1292 | * Do not use this interface for anything new, it exists for compatibility | |
1293 | * with bad ideas only. New subsystems should use plain subsystems; and | |
1294 | * add the subsystem-wide attributes should be added to the subsystem | |
1295 | * directory itself and not some create fake root-device placed in | |
1296 | * /sys/devices/system/<name>. | |
1297 | */ | |
1298 | int subsys_system_register(struct bus_type *subsys, | |
1299 | const struct attribute_group **groups) | |
1300 | { | |
1301 | return subsys_register(subsys, groups, &system_kset->kobj); | |
1302 | } | |
ca22e56d KS |
1303 | EXPORT_SYMBOL_GPL(subsys_system_register); |
1304 | ||
d73ce004 TH |
1305 | /** |
1306 | * subsys_virtual_register - register a subsystem at /sys/devices/virtual/ | |
1307 | * @subsys: virtual subsystem | |
1308 | * @groups: default attributes for the root device | |
1309 | * | |
1310 | * All 'virtual' subsystems have a /sys/devices/system/<name> root device | |
1311 | * with the name of the subystem. The root device can carry subsystem-wide | |
1312 | * attributes. All registered devices are below this single root device. | |
1313 | * There's no restriction on device naming. This is for kernel software | |
1314 | * constructs which need sysfs interface. | |
1315 | */ | |
1316 | int subsys_virtual_register(struct bus_type *subsys, | |
1317 | const struct attribute_group **groups) | |
1318 | { | |
1319 | struct kobject *virtual_dir; | |
1320 | ||
1321 | virtual_dir = virtual_device_parent(NULL); | |
1322 | if (!virtual_dir) | |
1323 | return -ENOMEM; | |
1324 | ||
1325 | return subsys_register(subsys, groups, virtual_dir); | |
1326 | } | |
1c04fc35 | 1327 | EXPORT_SYMBOL_GPL(subsys_virtual_register); |
d73ce004 | 1328 | |
1da177e4 LT |
1329 | int __init buses_init(void) |
1330 | { | |
59a54833 GKH |
1331 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1332 | if (!bus_kset) | |
1333 | return -ENOMEM; | |
ca22e56d KS |
1334 | |
1335 | system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); | |
1336 | if (!system_kset) | |
1337 | return -ENOMEM; | |
1338 | ||
59a54833 | 1339 | return 0; |
1da177e4 | 1340 | } |