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> |
63967685 | 20 | #include <linux/sysfs.h> |
1da177e4 LT |
21 | #include "base.h" |
22 | #include "power/power.h" | |
23 | ||
ca22e56d | 24 | /* /sys/devices/system */ |
97ec448a | 25 | static struct kset *system_kset; |
ca22e56d | 26 | |
1da177e4 | 27 | #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) |
1da177e4 LT |
28 | |
29 | /* | |
30 | * sysfs bindings for drivers | |
31 | */ | |
32 | ||
33 | #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) | |
1da177e4 LT |
34 | |
35 | ||
b8c5cec2 KS |
36 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
37 | void *data); | |
38 | ||
5901d014 GKH |
39 | static struct bus_type *bus_get(struct bus_type *bus) |
40 | { | |
c6f7e72a GKH |
41 | if (bus) { |
42 | kset_get(&bus->p->subsys); | |
43 | return bus; | |
44 | } | |
45 | return NULL; | |
5901d014 GKH |
46 | } |
47 | ||
fc1ede58 GKH |
48 | static void bus_put(struct bus_type *bus) |
49 | { | |
c6f7e72a GKH |
50 | if (bus) |
51 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
52 | } |
53 | ||
4a3ad20c GKH |
54 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
55 | char *buf) | |
1da177e4 | 56 | { |
4a3ad20c | 57 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 58 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 59 | ssize_t ret = -EIO; |
1da177e4 LT |
60 | |
61 | if (drv_attr->show) | |
e5dd1278 | 62 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
63 | return ret; |
64 | } | |
65 | ||
4a3ad20c GKH |
66 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
67 | const char *buf, size_t count) | |
1da177e4 | 68 | { |
4a3ad20c | 69 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 70 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 71 | ssize_t ret = -EIO; |
1da177e4 LT |
72 | |
73 | if (drv_attr->store) | |
e5dd1278 | 74 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
75 | return ret; |
76 | } | |
77 | ||
52cf25d0 | 78 | static const struct sysfs_ops driver_sysfs_ops = { |
1da177e4 LT |
79 | .show = drv_attr_show, |
80 | .store = drv_attr_store, | |
81 | }; | |
82 | ||
e5dd1278 | 83 | static void driver_release(struct kobject *kobj) |
1da177e4 | 84 | { |
e5dd1278 GKH |
85 | struct driver_private *drv_priv = to_driver(kobj); |
86 | ||
2b3a302a | 87 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 88 | kfree(drv_priv); |
1da177e4 LT |
89 | } |
90 | ||
a1148fb0 | 91 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
92 | .sysfs_ops = &driver_sysfs_ops, |
93 | .release = driver_release, | |
94 | }; | |
95 | ||
1da177e4 LT |
96 | /* |
97 | * sysfs bindings for buses | |
98 | */ | |
4a3ad20c GKH |
99 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
100 | char *buf) | |
1da177e4 | 101 | { |
4a3ad20c | 102 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 103 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
104 | ssize_t ret = 0; |
105 | ||
106 | if (bus_attr->show) | |
6b6e39a6 | 107 | ret = bus_attr->show(subsys_priv->bus, buf); |
1da177e4 LT |
108 | return ret; |
109 | } | |
110 | ||
4a3ad20c GKH |
111 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
112 | const char *buf, size_t count) | |
1da177e4 | 113 | { |
4a3ad20c | 114 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 115 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
116 | ssize_t ret = 0; |
117 | ||
118 | if (bus_attr->store) | |
6b6e39a6 | 119 | ret = bus_attr->store(subsys_priv->bus, buf, count); |
1da177e4 LT |
120 | return ret; |
121 | } | |
122 | ||
52cf25d0 | 123 | static const struct sysfs_ops bus_sysfs_ops = { |
1da177e4 LT |
124 | .show = bus_attr_show, |
125 | .store = bus_attr_store, | |
126 | }; | |
127 | ||
4a3ad20c | 128 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
129 | { |
130 | int error; | |
5901d014 | 131 | if (bus_get(bus)) { |
c6f7e72a | 132 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 133 | bus_put(bus); |
1da177e4 LT |
134 | } else |
135 | error = -EINVAL; | |
136 | return error; | |
137 | } | |
4a3ad20c | 138 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 139 | |
4a3ad20c | 140 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 141 | { |
5901d014 | 142 | if (bus_get(bus)) { |
c6f7e72a | 143 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 144 | bus_put(bus); |
1da177e4 LT |
145 | } |
146 | } | |
4a3ad20c | 147 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 148 | |
80f03e34 | 149 | static struct kobj_type bus_ktype = { |
1da177e4 | 150 | .sysfs_ops = &bus_sysfs_ops, |
80f03e34 KS |
151 | }; |
152 | ||
153 | static int bus_uevent_filter(struct kset *kset, struct kobject *kobj) | |
154 | { | |
155 | struct kobj_type *ktype = get_ktype(kobj); | |
156 | ||
157 | if (ktype == &bus_ktype) | |
158 | return 1; | |
159 | return 0; | |
160 | } | |
1da177e4 | 161 | |
9cd43611 | 162 | static const struct kset_uevent_ops bus_uevent_ops = { |
80f03e34 | 163 | .filter = bus_uevent_filter, |
1da177e4 LT |
164 | }; |
165 | ||
59a54833 | 166 | static struct kset *bus_kset; |
1da177e4 | 167 | |
2b08c8d0 | 168 | /* Manually detach a device from its associated driver. */ |
2581c9cc GKH |
169 | static ssize_t unbind_store(struct device_driver *drv, const char *buf, |
170 | size_t count) | |
151ef38f | 171 | { |
5901d014 | 172 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
173 | struct device *dev; |
174 | int err = -ENODEV; | |
175 | ||
1f9ffc04 | 176 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 177 | if (dev && dev->driver == drv) { |
bf74ad5b | 178 | if (dev->parent) /* Needed for USB */ |
8e9394ce | 179 | device_lock(dev->parent); |
151ef38f | 180 | device_release_driver(dev); |
bf74ad5b | 181 | if (dev->parent) |
8e9394ce | 182 | device_unlock(dev->parent); |
151ef38f GKH |
183 | err = count; |
184 | } | |
2b08c8d0 | 185 | put_device(dev); |
fc1ede58 | 186 | bus_put(bus); |
2b08c8d0 | 187 | return err; |
151ef38f | 188 | } |
2581c9cc | 189 | static DRIVER_ATTR_WO(unbind); |
151ef38f | 190 | |
afdce75f GKH |
191 | /* |
192 | * Manually attach a device to a driver. | |
193 | * Note: the driver must want to bind to the device, | |
194 | * it is not possible to override the driver's id table. | |
195 | */ | |
2581c9cc GKH |
196 | static ssize_t bind_store(struct device_driver *drv, const char *buf, |
197 | size_t count) | |
afdce75f | 198 | { |
5901d014 | 199 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
200 | struct device *dev; |
201 | int err = -ENODEV; | |
202 | ||
1f9ffc04 | 203 | dev = bus_find_device_by_name(bus, NULL, buf); |
49b420a1 | 204 | if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { |
bf74ad5b | 205 | if (dev->parent) /* Needed for USB */ |
8e9394ce GKH |
206 | device_lock(dev->parent); |
207 | device_lock(dev); | |
afdce75f | 208 | err = driver_probe_device(drv, dev); |
8e9394ce | 209 | device_unlock(dev); |
bf74ad5b | 210 | if (dev->parent) |
8e9394ce | 211 | device_unlock(dev->parent); |
37225401 | 212 | |
4a3ad20c GKH |
213 | if (err > 0) { |
214 | /* success */ | |
37225401 | 215 | err = count; |
4a3ad20c GKH |
216 | } else if (err == 0) { |
217 | /* driver didn't accept device */ | |
37225401 | 218 | err = -ENODEV; |
4a3ad20c | 219 | } |
afdce75f | 220 | } |
2b08c8d0 | 221 | put_device(dev); |
fc1ede58 | 222 | bus_put(bus); |
2b08c8d0 | 223 | return err; |
afdce75f | 224 | } |
2581c9cc | 225 | static DRIVER_ATTR_WO(bind); |
afdce75f | 226 | |
b8c5cec2 KS |
227 | static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) |
228 | { | |
c6f7e72a | 229 | return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
230 | } |
231 | ||
232 | static ssize_t store_drivers_autoprobe(struct bus_type *bus, | |
233 | const char *buf, size_t count) | |
234 | { | |
235 | if (buf[0] == '0') | |
c6f7e72a | 236 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 237 | else |
c6f7e72a | 238 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
239 | return count; |
240 | } | |
241 | ||
242 | static ssize_t store_drivers_probe(struct bus_type *bus, | |
243 | const char *buf, size_t count) | |
244 | { | |
245 | struct device *dev; | |
246 | ||
1f9ffc04 | 247 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
248 | if (!dev) |
249 | return -ENODEV; | |
250 | if (bus_rescan_devices_helper(dev, NULL) != 0) | |
251 | return -EINVAL; | |
252 | return count; | |
253 | } | |
151ef38f | 254 | |
4a3ad20c | 255 | static struct device *next_device(struct klist_iter *i) |
465c7a3a | 256 | { |
4a3ad20c | 257 | struct klist_node *n = klist_next(i); |
ae1b4171 GKH |
258 | struct device *dev = NULL; |
259 | struct device_private *dev_prv; | |
260 | ||
261 | if (n) { | |
262 | dev_prv = to_device_private_bus(n); | |
263 | dev = dev_prv->device; | |
264 | } | |
265 | return dev; | |
465c7a3a | 266 | } |
267 | ||
1da177e4 | 268 | /** |
4a3ad20c GKH |
269 | * bus_for_each_dev - device iterator. |
270 | * @bus: bus type. | |
271 | * @start: device to start iterating from. | |
272 | * @data: data for the callback. | |
273 | * @fn: function to be called for each device. | |
1da177e4 | 274 | * |
4a3ad20c GKH |
275 | * Iterate over @bus's list of devices, and call @fn for each, |
276 | * passing it @data. If @start is not NULL, we use that device to | |
277 | * begin iterating from. | |
1da177e4 | 278 | * |
4a3ad20c GKH |
279 | * We check the return of @fn each time. If it returns anything |
280 | * other than 0, we break out and return that value. | |
1da177e4 | 281 | * |
4a3ad20c GKH |
282 | * NOTE: The device that returns a non-zero value is not retained |
283 | * in any way, nor is its refcount incremented. If the caller needs | |
0fa1b0a1 | 284 | * to retain this data, it should do so, and increment the reference |
4a3ad20c | 285 | * count in the supplied callback. |
1da177e4 | 286 | */ |
4a3ad20c GKH |
287 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
288 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 289 | { |
465c7a3a | 290 | struct klist_iter i; |
4a3ad20c | 291 | struct device *dev; |
465c7a3a | 292 | int error = 0; |
1da177e4 | 293 | |
4fa3e78b | 294 | if (!bus || !bus->p) |
465c7a3a | 295 | return -EINVAL; |
296 | ||
7cd9c9bb GKH |
297 | klist_iter_init_node(&bus->p->klist_devices, &i, |
298 | (start ? &start->p->knode_bus : NULL)); | |
299 | while ((dev = next_device(&i)) && !error) | |
300 | error = fn(dev, data); | |
301 | klist_iter_exit(&i); | |
465c7a3a | 302 | return error; |
1da177e4 | 303 | } |
4a3ad20c | 304 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 305 | |
0edb5860 CH |
306 | /** |
307 | * bus_find_device - device iterator for locating a particular device. | |
308 | * @bus: bus type | |
309 | * @start: Device to begin with | |
310 | * @data: Data to pass to match function | |
311 | * @match: Callback function to check device | |
312 | * | |
313 | * This is similar to the bus_for_each_dev() function above, but it | |
314 | * returns a reference to a device that is 'found' for later use, as | |
315 | * determined by the @match callback. | |
316 | * | |
317 | * The callback should return 0 if the device doesn't match and non-zero | |
318 | * if it does. If the callback returns non-zero, this function will | |
319 | * return to the caller and not iterate over any more devices. | |
320 | */ | |
4a3ad20c GKH |
321 | struct device *bus_find_device(struct bus_type *bus, |
322 | struct device *start, void *data, | |
323 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
324 | { |
325 | struct klist_iter i; | |
326 | struct device *dev; | |
327 | ||
4fa3e78b | 328 | if (!bus || !bus->p) |
0edb5860 CH |
329 | return NULL; |
330 | ||
7cd9c9bb GKH |
331 | klist_iter_init_node(&bus->p->klist_devices, &i, |
332 | (start ? &start->p->knode_bus : NULL)); | |
0edb5860 CH |
333 | while ((dev = next_device(&i))) |
334 | if (match(dev, data) && get_device(dev)) | |
335 | break; | |
336 | klist_iter_exit(&i); | |
337 | return dev; | |
338 | } | |
4a3ad20c | 339 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 340 | |
1f9ffc04 GKH |
341 | static int match_name(struct device *dev, void *data) |
342 | { | |
343 | const char *name = data; | |
344 | ||
1e0b2cf9 | 345 | return sysfs_streq(name, dev_name(dev)); |
1f9ffc04 GKH |
346 | } |
347 | ||
348 | /** | |
349 | * bus_find_device_by_name - device iterator for locating a particular device of a specific name | |
350 | * @bus: bus type | |
351 | * @start: Device to begin with | |
352 | * @name: name of the device to match | |
353 | * | |
354 | * This is similar to the bus_find_device() function above, but it handles | |
355 | * searching by a name automatically, no need to write another strcmp matching | |
356 | * function. | |
357 | */ | |
358 | struct device *bus_find_device_by_name(struct bus_type *bus, | |
359 | struct device *start, const char *name) | |
360 | { | |
361 | return bus_find_device(bus, start, (void *)name, match_name); | |
362 | } | |
363 | EXPORT_SYMBOL_GPL(bus_find_device_by_name); | |
364 | ||
ca22e56d KS |
365 | /** |
366 | * subsys_find_device_by_id - find a device with a specific enumeration number | |
367 | * @subsys: subsystem | |
368 | * @id: index 'id' in struct device | |
369 | * @hint: device to check first | |
370 | * | |
371 | * Check the hint's next object and if it is a match return it directly, | |
372 | * otherwise, fall back to a full list search. Either way a reference for | |
373 | * the returned object is taken. | |
374 | */ | |
375 | struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id, | |
376 | struct device *hint) | |
377 | { | |
378 | struct klist_iter i; | |
379 | struct device *dev; | |
380 | ||
381 | if (!subsys) | |
382 | return NULL; | |
383 | ||
384 | if (hint) { | |
7cd9c9bb | 385 | klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus); |
ca22e56d KS |
386 | dev = next_device(&i); |
387 | if (dev && dev->id == id && get_device(dev)) { | |
388 | klist_iter_exit(&i); | |
389 | return dev; | |
390 | } | |
391 | klist_iter_exit(&i); | |
392 | } | |
393 | ||
394 | klist_iter_init_node(&subsys->p->klist_devices, &i, NULL); | |
395 | while ((dev = next_device(&i))) { | |
396 | if (dev->id == id && get_device(dev)) { | |
397 | klist_iter_exit(&i); | |
398 | return dev; | |
399 | } | |
400 | } | |
401 | klist_iter_exit(&i); | |
402 | return NULL; | |
403 | } | |
404 | EXPORT_SYMBOL_GPL(subsys_find_device_by_id); | |
405 | ||
4a3ad20c | 406 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 407 | { |
4a3ad20c | 408 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
409 | struct driver_private *drv_priv; |
410 | ||
411 | if (n) { | |
412 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
413 | return drv_priv->driver; | |
414 | } | |
415 | return NULL; | |
38fdac3c | 416 | } |
417 | ||
1da177e4 | 418 | /** |
4a3ad20c GKH |
419 | * bus_for_each_drv - driver iterator |
420 | * @bus: bus we're dealing with. | |
421 | * @start: driver to start iterating on. | |
422 | * @data: data to pass to the callback. | |
423 | * @fn: function to call for each driver. | |
1da177e4 | 424 | * |
4a3ad20c GKH |
425 | * This is nearly identical to the device iterator above. |
426 | * We iterate over each driver that belongs to @bus, and call | |
427 | * @fn for each. If @fn returns anything but 0, we break out | |
428 | * and return it. If @start is not NULL, we use it as the head | |
429 | * of the list. | |
1da177e4 | 430 | * |
4a3ad20c GKH |
431 | * NOTE: we don't return the driver that returns a non-zero |
432 | * value, nor do we leave the reference count incremented for that | |
433 | * driver. If the caller needs to know that info, it must set it | |
434 | * in the callback. It must also be sure to increment the refcount | |
435 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 436 | */ |
4a3ad20c GKH |
437 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
438 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 439 | { |
38fdac3c | 440 | struct klist_iter i; |
4a3ad20c | 441 | struct device_driver *drv; |
38fdac3c | 442 | int error = 0; |
1da177e4 | 443 | |
38fdac3c | 444 | if (!bus) |
445 | return -EINVAL; | |
446 | ||
7cd9c9bb GKH |
447 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
448 | start ? &start->p->knode_bus : NULL); | |
449 | while ((drv = next_driver(&i)) && !error) | |
450 | error = fn(drv, data); | |
451 | klist_iter_exit(&i); | |
38fdac3c | 452 | return error; |
1da177e4 | 453 | } |
4a3ad20c | 454 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 455 | |
4aca67e5 | 456 | static int device_add_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
457 | { |
458 | int error = 0; | |
459 | int i; | |
460 | ||
4aca67e5 AM |
461 | if (!bus->dev_attrs) |
462 | return 0; | |
463 | ||
3e1026b3 | 464 | for (i = 0; bus->dev_attrs[i].attr.name; i++) { |
4a3ad20c | 465 | error = device_create_file(dev, &bus->dev_attrs[i]); |
4aca67e5 AM |
466 | if (error) { |
467 | while (--i >= 0) | |
468 | device_remove_file(dev, &bus->dev_attrs[i]); | |
469 | break; | |
1da177e4 LT |
470 | } |
471 | } | |
1da177e4 | 472 | return error; |
1da177e4 LT |
473 | } |
474 | ||
4a3ad20c | 475 | static void device_remove_attrs(struct bus_type *bus, struct device *dev) |
1da177e4 LT |
476 | { |
477 | int i; | |
478 | ||
479 | if (bus->dev_attrs) { | |
3e1026b3 | 480 | for (i = 0; bus->dev_attrs[i].attr.name; i++) |
4a3ad20c | 481 | device_remove_file(dev, &bus->dev_attrs[i]); |
1da177e4 LT |
482 | } |
483 | } | |
484 | ||
1da177e4 | 485 | /** |
4a3ad20c GKH |
486 | * bus_add_device - add device to bus |
487 | * @dev: device being added | |
1da177e4 | 488 | * |
2023c610 AS |
489 | * - Add device's bus attributes. |
490 | * - Create links to device's bus. | |
4a3ad20c | 491 | * - Add the device to its bus's list of devices. |
1da177e4 | 492 | */ |
4a3ad20c | 493 | int bus_add_device(struct device *dev) |
1da177e4 | 494 | { |
4a3ad20c | 495 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
496 | int error = 0; |
497 | ||
498 | if (bus) { | |
1e0b2cf9 | 499 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
d377e85b | 500 | error = device_add_attrs(bus, dev); |
f86db396 | 501 | if (error) |
513e7337 | 502 | goto out_put; |
fa6fdb33 GKH |
503 | error = device_add_groups(dev, bus->dev_groups); |
504 | if (error) | |
505 | goto out_groups; | |
c6f7e72a | 506 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 507 | &dev->kobj, dev_name(dev)); |
f86db396 | 508 | if (error) |
513e7337 | 509 | goto out_id; |
f86db396 | 510 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 511 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 512 | if (error) |
513e7337 | 513 | goto out_subsys; |
2023c610 | 514 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 515 | } |
513e7337 CH |
516 | return 0; |
517 | ||
513e7337 | 518 | out_subsys: |
1e0b2cf9 | 519 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
fa6fdb33 GKH |
520 | out_groups: |
521 | device_remove_groups(dev, bus->dev_groups); | |
513e7337 CH |
522 | out_id: |
523 | device_remove_attrs(bus, dev); | |
524 | out_put: | |
fc1ede58 | 525 | bus_put(dev->bus); |
1da177e4 LT |
526 | return error; |
527 | } | |
528 | ||
53877d06 | 529 | /** |
2023c610 AS |
530 | * bus_probe_device - probe drivers for a new device |
531 | * @dev: device to probe | |
53877d06 | 532 | * |
2023c610 | 533 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 534 | */ |
2023c610 | 535 | void bus_probe_device(struct device *dev) |
53877d06 | 536 | { |
f86db396 | 537 | struct bus_type *bus = dev->bus; |
ca22e56d | 538 | struct subsys_interface *sif; |
2023c610 | 539 | int ret; |
53877d06 | 540 | |
ca22e56d KS |
541 | if (!bus) |
542 | return; | |
543 | ||
544 | if (bus->p->drivers_autoprobe) { | |
2023c610 | 545 | ret = device_attach(dev); |
c6a46696 | 546 | WARN_ON(ret < 0); |
53877d06 | 547 | } |
ca22e56d KS |
548 | |
549 | mutex_lock(&bus->p->mutex); | |
550 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
551 | if (sif->add_dev) | |
552 | sif->add_dev(dev, sif); | |
553 | mutex_unlock(&bus->p->mutex); | |
53877d06 KS |
554 | } |
555 | ||
1da177e4 | 556 | /** |
4a3ad20c GKH |
557 | * bus_remove_device - remove device from bus |
558 | * @dev: device to be removed | |
1da177e4 | 559 | * |
ca22e56d KS |
560 | * - Remove device from all interfaces. |
561 | * - Remove symlink from bus' directory. | |
4a3ad20c GKH |
562 | * - Delete device from bus's list. |
563 | * - Detach from its driver. | |
564 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 565 | */ |
4a3ad20c | 566 | void bus_remove_device(struct device *dev) |
1da177e4 | 567 | { |
ca22e56d KS |
568 | struct bus_type *bus = dev->bus; |
569 | struct subsys_interface *sif; | |
570 | ||
571 | if (!bus) | |
572 | return; | |
573 | ||
574 | mutex_lock(&bus->p->mutex); | |
575 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
576 | if (sif->remove_dev) | |
577 | sif->remove_dev(dev, sif); | |
578 | mutex_unlock(&bus->p->mutex); | |
579 | ||
580 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
581 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, | |
582 | dev_name(dev)); | |
583 | device_remove_attrs(dev->bus, dev); | |
fa6fdb33 | 584 | device_remove_groups(dev, dev->bus->dev_groups); |
ca22e56d KS |
585 | if (klist_node_attached(&dev->p->knode_bus)) |
586 | klist_del(&dev->p->knode_bus); | |
587 | ||
588 | pr_debug("bus: '%s': remove device %s\n", | |
589 | dev->bus->name, dev_name(dev)); | |
590 | device_release_driver(dev); | |
591 | bus_put(dev->bus); | |
1da177e4 LT |
592 | } |
593 | ||
f86db396 | 594 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 595 | { |
f86db396 AM |
596 | int ret; |
597 | ||
598 | ret = driver_create_file(drv, &driver_attr_unbind); | |
599 | if (ret == 0) { | |
600 | ret = driver_create_file(drv, &driver_attr_bind); | |
601 | if (ret) | |
602 | driver_remove_file(drv, &driver_attr_unbind); | |
603 | } | |
604 | return ret; | |
874c6241 GKH |
605 | } |
606 | ||
607 | static void remove_bind_files(struct device_driver *drv) | |
608 | { | |
609 | driver_remove_file(drv, &driver_attr_bind); | |
610 | driver_remove_file(drv, &driver_attr_unbind); | |
611 | } | |
b8c5cec2 | 612 | |
8380770c KS |
613 | static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); |
614 | static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, | |
615 | show_drivers_autoprobe, store_drivers_autoprobe); | |
616 | ||
b8c5cec2 KS |
617 | static int add_probe_files(struct bus_type *bus) |
618 | { | |
619 | int retval; | |
620 | ||
8380770c | 621 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
622 | if (retval) |
623 | goto out; | |
624 | ||
8380770c | 625 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 626 | if (retval) |
8380770c | 627 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
628 | out: |
629 | return retval; | |
630 | } | |
631 | ||
632 | static void remove_probe_files(struct bus_type *bus) | |
633 | { | |
8380770c KS |
634 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
635 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 636 | } |
1da177e4 | 637 | |
2581c9cc GKH |
638 | static ssize_t uevent_store(struct device_driver *drv, const char *buf, |
639 | size_t count) | |
7ac1cf4a KS |
640 | { |
641 | enum kobject_action action; | |
642 | ||
643 | if (kobject_action_type(buf, count, &action) == 0) | |
e5dd1278 | 644 | kobject_uevent(&drv->p->kobj, action); |
7ac1cf4a KS |
645 | return count; |
646 | } | |
2581c9cc | 647 | static DRIVER_ATTR_WO(uevent); |
7ac1cf4a | 648 | |
1da177e4 | 649 | /** |
4a3ad20c GKH |
650 | * bus_add_driver - Add a driver to the bus. |
651 | * @drv: driver. | |
1da177e4 | 652 | */ |
f86db396 | 653 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 654 | { |
e5dd1278 GKH |
655 | struct bus_type *bus; |
656 | struct driver_private *priv; | |
1da177e4 LT |
657 | int error = 0; |
658 | ||
e5dd1278 | 659 | bus = bus_get(drv->bus); |
d9fd4d3b | 660 | if (!bus) |
4f6e1945 | 661 | return -EINVAL; |
d9fd4d3b | 662 | |
7dc72b28 | 663 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
664 | |
665 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
666 | if (!priv) { |
667 | error = -ENOMEM; | |
668 | goto out_put_bus; | |
669 | } | |
e5dd1278 GKH |
670 | klist_init(&priv->klist_devices, NULL, NULL); |
671 | priv->driver = drv; | |
672 | drv->p = priv; | |
c8e90d82 GKH |
673 | priv->kobj.kset = bus->p->drivers_kset; |
674 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
675 | "%s", drv->name); | |
dc0afa83 | 676 | if (error) |
07634464 | 677 | goto out_unregister; |
d9fd4d3b | 678 | |
190888ac | 679 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
c6f7e72a | 680 | if (drv->bus->p->drivers_autoprobe) { |
b8c5cec2 KS |
681 | error = driver_attach(drv); |
682 | if (error) | |
683 | goto out_unregister; | |
684 | } | |
d9fd4d3b JG |
685 | module_add_driver(drv->owner, drv); |
686 | ||
7ac1cf4a KS |
687 | error = driver_create_file(drv, &driver_attr_uevent); |
688 | if (error) { | |
689 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 690 | __func__, drv->name); |
7ac1cf4a | 691 | } |
e18945b1 | 692 | error = driver_add_groups(drv, bus->drv_groups); |
d9fd4d3b JG |
693 | if (error) { |
694 | /* How the hell do we get out of this pickle? Give up */ | |
ed0617b5 GKH |
695 | printk(KERN_ERR "%s: driver_create_groups(%s) failed\n", |
696 | __func__, drv->name); | |
e18945b1 | 697 | } |
1a6f2a75 DT |
698 | |
699 | if (!drv->suppress_bind_attrs) { | |
700 | error = add_bind_files(drv); | |
701 | if (error) { | |
702 | /* Ditto */ | |
703 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
704 | __func__, drv->name); | |
705 | } | |
1da177e4 | 706 | } |
d9fd4d3b | 707 | |
5c8563d7 | 708 | return 0; |
1a6f2a75 | 709 | |
f86db396 | 710 | out_unregister: |
99b28f1b | 711 | kobject_put(&priv->kobj); |
5c8563d7 KS |
712 | kfree(drv->p); |
713 | drv->p = NULL; | |
f86db396 | 714 | out_put_bus: |
fc1ede58 | 715 | bus_put(bus); |
f86db396 | 716 | return error; |
1da177e4 LT |
717 | } |
718 | ||
1da177e4 | 719 | /** |
4a3ad20c GKH |
720 | * bus_remove_driver - delete driver from bus's knowledge. |
721 | * @drv: driver. | |
1da177e4 | 722 | * |
4a3ad20c GKH |
723 | * Detach the driver from the devices it controls, and remove |
724 | * it from its bus's list of drivers. Finally, we drop the reference | |
725 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 726 | */ |
4a3ad20c | 727 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 728 | { |
d9fd4d3b JG |
729 | if (!drv->bus) |
730 | return; | |
731 | ||
1a6f2a75 DT |
732 | if (!drv->suppress_bind_attrs) |
733 | remove_bind_files(drv); | |
ed0617b5 | 734 | driver_remove_groups(drv, drv->bus->drv_groups); |
7ac1cf4a | 735 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 736 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 737 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
738 | driver_detach(drv); |
739 | module_remove_driver(drv); | |
c10997f6 | 740 | kobject_put(&drv->p->kobj); |
fc1ede58 | 741 | bus_put(drv->bus); |
1da177e4 LT |
742 | } |
743 | ||
1da177e4 | 744 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 745 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 746 | void *data) |
1da177e4 | 747 | { |
f86db396 AM |
748 | int ret = 0; |
749 | ||
bf74ad5b AS |
750 | if (!dev->driver) { |
751 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 752 | device_lock(dev->parent); |
f86db396 | 753 | ret = device_attach(dev); |
bf74ad5b | 754 | if (dev->parent) |
8e9394ce | 755 | device_unlock(dev->parent); |
bf74ad5b | 756 | } |
f86db396 | 757 | return ret < 0 ? ret : 0; |
1da177e4 LT |
758 | } |
759 | ||
1da177e4 | 760 | /** |
23d3d602 GKH |
761 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
762 | * @bus: the bus to scan. | |
1da177e4 | 763 | * |
23d3d602 GKH |
764 | * This function will look for devices on the bus with no driver |
765 | * attached and rescan it against existing drivers to see if it matches | |
766 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 767 | */ |
4a3ad20c | 768 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 769 | { |
f86db396 | 770 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 771 | } |
4a3ad20c | 772 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 773 | |
e935d5da ME |
774 | /** |
775 | * device_reprobe - remove driver for a device and probe for a new driver | |
776 | * @dev: the device to reprobe | |
777 | * | |
778 | * This function detaches the attached driver (if any) for the given | |
779 | * device and restarts the driver probing process. It is intended | |
780 | * to use if probing criteria changed during a devices lifetime and | |
781 | * driver attachment should change accordingly. | |
782 | */ | |
f86db396 | 783 | int device_reprobe(struct device *dev) |
e935d5da ME |
784 | { |
785 | if (dev->driver) { | |
786 | if (dev->parent) /* Needed for USB */ | |
8e9394ce | 787 | device_lock(dev->parent); |
e935d5da ME |
788 | device_release_driver(dev); |
789 | if (dev->parent) | |
8e9394ce | 790 | device_unlock(dev->parent); |
e935d5da | 791 | } |
f86db396 | 792 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
793 | } |
794 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 795 | |
1da177e4 | 796 | /** |
4a3ad20c GKH |
797 | * find_bus - locate bus by name. |
798 | * @name: name of bus. | |
1da177e4 | 799 | * |
4a3ad20c GKH |
800 | * Call kset_find_obj() to iterate over list of buses to |
801 | * find a bus by name. Return bus if found. | |
1da177e4 | 802 | * |
4a3ad20c | 803 | * Note that kset_find_obj increments bus' reference count. |
1da177e4 | 804 | */ |
7e4ef085 | 805 | #if 0 |
4a3ad20c | 806 | struct bus_type *find_bus(char *name) |
1da177e4 | 807 | { |
4a3ad20c | 808 | struct kobject *k = kset_find_obj(bus_kset, name); |
1da177e4 LT |
809 | return k ? to_bus(k) : NULL; |
810 | } | |
7e4ef085 | 811 | #endif /* 0 */ |
1da177e4 | 812 | |
12478ba0 GKH |
813 | static int bus_add_groups(struct bus_type *bus, |
814 | const struct attribute_group **groups) | |
815 | { | |
3e9b2bae | 816 | return sysfs_create_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
817 | } |
818 | ||
819 | static void bus_remove_groups(struct bus_type *bus, | |
820 | const struct attribute_group **groups) | |
821 | { | |
3e9b2bae | 822 | sysfs_remove_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
823 | } |
824 | ||
34bb61f9 JB |
825 | static void klist_devices_get(struct klist_node *n) |
826 | { | |
ae1b4171 GKH |
827 | struct device_private *dev_prv = to_device_private_bus(n); |
828 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
829 | |
830 | get_device(dev); | |
831 | } | |
832 | ||
833 | static void klist_devices_put(struct klist_node *n) | |
834 | { | |
ae1b4171 GKH |
835 | struct device_private *dev_prv = to_device_private_bus(n); |
836 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
837 | |
838 | put_device(dev); | |
839 | } | |
840 | ||
7ac1cf4a KS |
841 | static ssize_t bus_uevent_store(struct bus_type *bus, |
842 | const char *buf, size_t count) | |
843 | { | |
844 | enum kobject_action action; | |
845 | ||
846 | if (kobject_action_type(buf, count, &action) == 0) | |
c6f7e72a | 847 | kobject_uevent(&bus->p->subsys.kobj, action); |
7ac1cf4a KS |
848 | return count; |
849 | } | |
850 | static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); | |
851 | ||
1da177e4 | 852 | /** |
be871b7e | 853 | * bus_register - register a driver-core subsystem |
78d79559 | 854 | * @bus: bus to register |
1da177e4 | 855 | * |
78d79559 | 856 | * Once we have that, we register the bus with the kobject |
4a3ad20c | 857 | * infrastructure, then register the children subsystems it has: |
ca22e56d | 858 | * the devices and drivers that belong to the subsystem. |
1da177e4 | 859 | */ |
be871b7e | 860 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
861 | { |
862 | int retval; | |
6b6e39a6 | 863 | struct subsys_private *priv; |
be871b7e | 864 | struct lock_class_key *key = &bus->lock_key; |
c6f7e72a | 865 | |
6b6e39a6 | 866 | priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL); |
c6f7e72a GKH |
867 | if (!priv) |
868 | return -ENOMEM; | |
869 | ||
870 | priv->bus = bus; | |
871 | bus->p = priv; | |
1da177e4 | 872 | |
c6f7e72a | 873 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 874 | |
c6f7e72a | 875 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
876 | if (retval) |
877 | goto out; | |
878 | ||
c6f7e72a GKH |
879 | priv->subsys.kobj.kset = bus_kset; |
880 | priv->subsys.kobj.ktype = &bus_ktype; | |
881 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 882 | |
c6f7e72a | 883 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
884 | if (retval) |
885 | goto out; | |
886 | ||
7ac1cf4a KS |
887 | retval = bus_create_file(bus, &bus_attr_uevent); |
888 | if (retval) | |
889 | goto bus_uevent_fail; | |
890 | ||
c6f7e72a GKH |
891 | priv->devices_kset = kset_create_and_add("devices", NULL, |
892 | &priv->subsys.kobj); | |
893 | if (!priv->devices_kset) { | |
3d899596 | 894 | retval = -ENOMEM; |
1da177e4 | 895 | goto bus_devices_fail; |
3d899596 | 896 | } |
1da177e4 | 897 | |
c6f7e72a GKH |
898 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
899 | &priv->subsys.kobj); | |
900 | if (!priv->drivers_kset) { | |
6dcec251 | 901 | retval = -ENOMEM; |
1da177e4 | 902 | goto bus_drivers_fail; |
6dcec251 | 903 | } |
465c7a3a | 904 | |
ca22e56d KS |
905 | INIT_LIST_HEAD(&priv->interfaces); |
906 | __mutex_init(&priv->mutex, "subsys mutex", key); | |
c6f7e72a GKH |
907 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
908 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 909 | |
b8c5cec2 KS |
910 | retval = add_probe_files(bus); |
911 | if (retval) | |
912 | goto bus_probe_files_fail; | |
913 | ||
12478ba0 GKH |
914 | retval = bus_add_groups(bus, bus->bus_groups); |
915 | if (retval) | |
916 | goto bus_groups_fail; | |
1da177e4 | 917 | |
7dc72b28 | 918 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
919 | return 0; |
920 | ||
12478ba0 | 921 | bus_groups_fail: |
b8c5cec2 KS |
922 | remove_probe_files(bus); |
923 | bus_probe_files_fail: | |
c6f7e72a | 924 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 925 | bus_drivers_fail: |
c6f7e72a | 926 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 927 | bus_devices_fail: |
7ac1cf4a KS |
928 | bus_remove_file(bus, &bus_attr_uevent); |
929 | bus_uevent_fail: | |
c6f7e72a | 930 | kset_unregister(&bus->p->subsys); |
1da177e4 | 931 | out: |
600c20f3 | 932 | kfree(bus->p); |
f48f3feb | 933 | bus->p = NULL; |
1da177e4 LT |
934 | return retval; |
935 | } | |
be871b7e | 936 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 937 | |
1da177e4 | 938 | /** |
4a3ad20c GKH |
939 | * bus_unregister - remove a bus from the system |
940 | * @bus: bus. | |
1da177e4 | 941 | * |
4a3ad20c GKH |
942 | * Unregister the child subsystems and the bus itself. |
943 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 944 | */ |
4a3ad20c | 945 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 946 | { |
7dc72b28 | 947 | pr_debug("bus: '%s': unregistering\n", bus->name); |
ca22e56d KS |
948 | if (bus->dev_root) |
949 | device_unregister(bus->dev_root); | |
12478ba0 | 950 | bus_remove_groups(bus, bus->bus_groups); |
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); | |
f48f3feb | 957 | bus->p = NULL; |
1da177e4 | 958 | } |
4a3ad20c | 959 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 960 | |
116af378 BH |
961 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
962 | { | |
c6f7e72a | 963 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
964 | } |
965 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
966 | ||
967 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
968 | { | |
c6f7e72a | 969 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
970 | } |
971 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
972 | ||
0fed80f7 GKH |
973 | struct kset *bus_get_kset(struct bus_type *bus) |
974 | { | |
c6f7e72a | 975 | return &bus->p->subsys; |
0fed80f7 GKH |
976 | } |
977 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
978 | ||
b249072e GKH |
979 | struct klist *bus_get_device_klist(struct bus_type *bus) |
980 | { | |
c6f7e72a | 981 | return &bus->p->klist_devices; |
b249072e GKH |
982 | } |
983 | EXPORT_SYMBOL_GPL(bus_get_device_klist); | |
984 | ||
99178b03 | 985 | /* |
dca25ebd | 986 | * Yes, this forcibly breaks the klist abstraction temporarily. It |
99178b03 GKH |
987 | * just wants to sort the klist, not change reference counts and |
988 | * take/drop locks rapidly in the process. It does all this while | |
989 | * holding the lock for the list, so objects can't otherwise be | |
990 | * added/removed while we're swizzling. | |
991 | */ | |
992 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
993 | int (*compare)(const struct device *a, | |
994 | const struct device *b)) | |
995 | { | |
996 | struct list_head *pos; | |
997 | struct klist_node *n; | |
ae1b4171 | 998 | struct device_private *dev_prv; |
99178b03 GKH |
999 | struct device *b; |
1000 | ||
1001 | list_for_each(pos, list) { | |
1002 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1003 | dev_prv = to_device_private_bus(n); |
1004 | b = dev_prv->device; | |
99178b03 | 1005 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
1006 | list_move_tail(&a->p->knode_bus.n_node, |
1007 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
1008 | return; |
1009 | } | |
1010 | } | |
ae1b4171 | 1011 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
1012 | } |
1013 | ||
1014 | void bus_sort_breadthfirst(struct bus_type *bus, | |
1015 | int (*compare)(const struct device *a, | |
1016 | const struct device *b)) | |
1017 | { | |
1018 | LIST_HEAD(sorted_devices); | |
1019 | struct list_head *pos, *tmp; | |
1020 | struct klist_node *n; | |
ae1b4171 | 1021 | struct device_private *dev_prv; |
99178b03 GKH |
1022 | struct device *dev; |
1023 | struct klist *device_klist; | |
1024 | ||
1025 | device_klist = bus_get_device_klist(bus); | |
1026 | ||
1027 | spin_lock(&device_klist->k_lock); | |
1028 | list_for_each_safe(pos, tmp, &device_klist->k_list) { | |
1029 | n = container_of(pos, struct klist_node, n_node); | |
ae1b4171 GKH |
1030 | dev_prv = to_device_private_bus(n); |
1031 | dev = dev_prv->device; | |
99178b03 GKH |
1032 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
1033 | } | |
1034 | list_splice(&sorted_devices, &device_klist->k_list); | |
1035 | spin_unlock(&device_klist->k_lock); | |
1036 | } | |
1037 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
1038 | ||
ca22e56d KS |
1039 | /** |
1040 | * subsys_dev_iter_init - initialize subsys device iterator | |
1041 | * @iter: subsys iterator to initialize | |
1042 | * @subsys: the subsys we wanna iterate over | |
1043 | * @start: the device to start iterating from, if any | |
1044 | * @type: device_type of the devices to iterate over, NULL for all | |
1045 | * | |
1046 | * Initialize subsys iterator @iter such that it iterates over devices | |
1047 | * of @subsys. If @start is set, the list iteration will start there, | |
1048 | * otherwise if it is NULL, the iteration starts at the beginning of | |
1049 | * the list. | |
1050 | */ | |
7cd9c9bb GKH |
1051 | void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys, |
1052 | struct device *start, const struct device_type *type) | |
ca22e56d KS |
1053 | { |
1054 | struct klist_node *start_knode = NULL; | |
1055 | ||
1056 | if (start) | |
1057 | start_knode = &start->p->knode_bus; | |
7cd9c9bb GKH |
1058 | klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode); |
1059 | iter->type = type; | |
ca22e56d KS |
1060 | } |
1061 | EXPORT_SYMBOL_GPL(subsys_dev_iter_init); | |
1062 | ||
1063 | /** | |
1064 | * subsys_dev_iter_next - iterate to the next device | |
1065 | * @iter: subsys iterator to proceed | |
1066 | * | |
1067 | * Proceed @iter to the next device and return it. Returns NULL if | |
1068 | * iteration is complete. | |
1069 | * | |
1070 | * The returned device is referenced and won't be released till | |
1071 | * iterator is proceed to the next device or exited. The caller is | |
1072 | * free to do whatever it wants to do with the device including | |
1073 | * calling back into subsys code. | |
1074 | */ | |
1075 | struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter) | |
1076 | { | |
1077 | struct klist_node *knode; | |
1078 | struct device *dev; | |
1079 | ||
1080 | for (;;) { | |
1081 | knode = klist_next(&iter->ki); | |
1082 | if (!knode) | |
1083 | return NULL; | |
1084 | dev = container_of(knode, struct device_private, knode_bus)->device; | |
1085 | if (!iter->type || iter->type == dev->type) | |
1086 | return dev; | |
1087 | } | |
1088 | } | |
1089 | EXPORT_SYMBOL_GPL(subsys_dev_iter_next); | |
1090 | ||
1091 | /** | |
1092 | * subsys_dev_iter_exit - finish iteration | |
1093 | * @iter: subsys iterator to finish | |
1094 | * | |
1095 | * Finish an iteration. Always call this function after iteration is | |
1096 | * complete whether the iteration ran till the end or not. | |
1097 | */ | |
1098 | void subsys_dev_iter_exit(struct subsys_dev_iter *iter) | |
1099 | { | |
1100 | klist_iter_exit(&iter->ki); | |
1101 | } | |
1102 | EXPORT_SYMBOL_GPL(subsys_dev_iter_exit); | |
1103 | ||
1104 | int subsys_interface_register(struct subsys_interface *sif) | |
1105 | { | |
1106 | struct bus_type *subsys; | |
1107 | struct subsys_dev_iter iter; | |
1108 | struct device *dev; | |
1109 | ||
1110 | if (!sif || !sif->subsys) | |
1111 | return -ENODEV; | |
1112 | ||
1113 | subsys = bus_get(sif->subsys); | |
1114 | if (!subsys) | |
1115 | return -EINVAL; | |
1116 | ||
1117 | mutex_lock(&subsys->p->mutex); | |
1118 | list_add_tail(&sif->node, &subsys->p->interfaces); | |
1119 | if (sif->add_dev) { | |
1120 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1121 | while ((dev = subsys_dev_iter_next(&iter))) | |
1122 | sif->add_dev(dev, sif); | |
1123 | subsys_dev_iter_exit(&iter); | |
1124 | } | |
1125 | mutex_unlock(&subsys->p->mutex); | |
1126 | ||
1127 | return 0; | |
1128 | } | |
1129 | EXPORT_SYMBOL_GPL(subsys_interface_register); | |
1130 | ||
1131 | void subsys_interface_unregister(struct subsys_interface *sif) | |
1132 | { | |
2b31594a | 1133 | struct bus_type *subsys; |
ca22e56d KS |
1134 | struct subsys_dev_iter iter; |
1135 | struct device *dev; | |
1136 | ||
2b31594a | 1137 | if (!sif || !sif->subsys) |
ca22e56d KS |
1138 | return; |
1139 | ||
2b31594a JC |
1140 | subsys = sif->subsys; |
1141 | ||
ca22e56d KS |
1142 | mutex_lock(&subsys->p->mutex); |
1143 | list_del_init(&sif->node); | |
1144 | if (sif->remove_dev) { | |
1145 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1146 | while ((dev = subsys_dev_iter_next(&iter))) | |
1147 | sif->remove_dev(dev, sif); | |
1148 | subsys_dev_iter_exit(&iter); | |
1149 | } | |
1150 | mutex_unlock(&subsys->p->mutex); | |
1151 | ||
1152 | bus_put(subsys); | |
1153 | } | |
1154 | EXPORT_SYMBOL_GPL(subsys_interface_unregister); | |
1155 | ||
1156 | static void system_root_device_release(struct device *dev) | |
1157 | { | |
1158 | kfree(dev); | |
1159 | } | |
d73ce004 TH |
1160 | |
1161 | static int subsys_register(struct bus_type *subsys, | |
1162 | const struct attribute_group **groups, | |
1163 | struct kobject *parent_of_root) | |
ca22e56d KS |
1164 | { |
1165 | struct device *dev; | |
1166 | int err; | |
1167 | ||
1168 | err = bus_register(subsys); | |
1169 | if (err < 0) | |
1170 | return err; | |
1171 | ||
1172 | dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
1173 | if (!dev) { | |
1174 | err = -ENOMEM; | |
1175 | goto err_dev; | |
1176 | } | |
1177 | ||
1178 | err = dev_set_name(dev, "%s", subsys->name); | |
1179 | if (err < 0) | |
1180 | goto err_name; | |
1181 | ||
d73ce004 | 1182 | dev->kobj.parent = parent_of_root; |
ca22e56d KS |
1183 | dev->groups = groups; |
1184 | dev->release = system_root_device_release; | |
1185 | ||
1186 | err = device_register(dev); | |
1187 | if (err < 0) | |
1188 | goto err_dev_reg; | |
1189 | ||
1190 | subsys->dev_root = dev; | |
1191 | return 0; | |
1192 | ||
1193 | err_dev_reg: | |
1194 | put_device(dev); | |
1195 | dev = NULL; | |
1196 | err_name: | |
1197 | kfree(dev); | |
1198 | err_dev: | |
1199 | bus_unregister(subsys); | |
1200 | return err; | |
1201 | } | |
d73ce004 TH |
1202 | |
1203 | /** | |
1204 | * subsys_system_register - register a subsystem at /sys/devices/system/ | |
1205 | * @subsys: system subsystem | |
1206 | * @groups: default attributes for the root device | |
1207 | * | |
1208 | * All 'system' subsystems have a /sys/devices/system/<name> root device | |
1209 | * with the name of the subsystem. The root device can carry subsystem- | |
1210 | * wide attributes. All registered devices are below this single root | |
1211 | * device and are named after the subsystem with a simple enumeration | |
e227867f | 1212 | * number appended. The registered devices are not explicitly named; |
d73ce004 TH |
1213 | * only 'id' in the device needs to be set. |
1214 | * | |
1215 | * Do not use this interface for anything new, it exists for compatibility | |
1216 | * with bad ideas only. New subsystems should use plain subsystems; and | |
1217 | * add the subsystem-wide attributes should be added to the subsystem | |
1218 | * directory itself and not some create fake root-device placed in | |
1219 | * /sys/devices/system/<name>. | |
1220 | */ | |
1221 | int subsys_system_register(struct bus_type *subsys, | |
1222 | const struct attribute_group **groups) | |
1223 | { | |
1224 | return subsys_register(subsys, groups, &system_kset->kobj); | |
1225 | } | |
ca22e56d KS |
1226 | EXPORT_SYMBOL_GPL(subsys_system_register); |
1227 | ||
d73ce004 TH |
1228 | /** |
1229 | * subsys_virtual_register - register a subsystem at /sys/devices/virtual/ | |
1230 | * @subsys: virtual subsystem | |
1231 | * @groups: default attributes for the root device | |
1232 | * | |
1233 | * All 'virtual' subsystems have a /sys/devices/system/<name> root device | |
1234 | * with the name of the subystem. The root device can carry subsystem-wide | |
1235 | * attributes. All registered devices are below this single root device. | |
1236 | * There's no restriction on device naming. This is for kernel software | |
1237 | * constructs which need sysfs interface. | |
1238 | */ | |
1239 | int subsys_virtual_register(struct bus_type *subsys, | |
1240 | const struct attribute_group **groups) | |
1241 | { | |
1242 | struct kobject *virtual_dir; | |
1243 | ||
1244 | virtual_dir = virtual_device_parent(NULL); | |
1245 | if (!virtual_dir) | |
1246 | return -ENOMEM; | |
1247 | ||
1248 | return subsys_register(subsys, groups, virtual_dir); | |
1249 | } | |
1c04fc35 | 1250 | EXPORT_SYMBOL_GPL(subsys_virtual_register); |
d73ce004 | 1251 | |
1da177e4 LT |
1252 | int __init buses_init(void) |
1253 | { | |
59a54833 GKH |
1254 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1255 | if (!bus_kset) | |
1256 | return -ENOMEM; | |
ca22e56d KS |
1257 | |
1258 | system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); | |
1259 | if (!system_kset) | |
1260 | return -ENOMEM; | |
1261 | ||
59a54833 | 1262 | return 0; |
1da177e4 | 1263 | } |