blob: 29f6af554e715ed408f0f23e8da838284dbc9dc7 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * bus.c - bus driver management
3 *
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
6 *
7 * This file is released under the GPLv2
8 *
9 */
10
11#include <linux/config.h>
12#include <linux/device.h>
13#include <linux/module.h>
14#include <linux/errno.h>
15#include <linux/init.h>
16#include <linux/string.h>
17#include "base.h"
18#include "power/power.h"
19
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)
21#define to_bus(obj) container_of(obj, struct bus_type, subsys.kset.kobj)
22
23/*
24 * sysfs bindings for drivers
25 */
26
27#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)
28#define to_driver(obj) container_of(obj, struct device_driver, kobj)
29
30
31static ssize_t
32drv_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
33{
34 struct driver_attribute * drv_attr = to_drv_attr(attr);
35 struct device_driver * drv = to_driver(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050036 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38 if (drv_attr->show)
39 ret = drv_attr->show(drv, buf);
40 return ret;
41}
42
43static ssize_t
44drv_attr_store(struct kobject * kobj, struct attribute * attr,
45 const char * buf, size_t count)
46{
47 struct driver_attribute * drv_attr = to_drv_attr(attr);
48 struct device_driver * drv = to_driver(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050049 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
51 if (drv_attr->store)
52 ret = drv_attr->store(drv, buf, count);
53 return ret;
54}
55
56static struct sysfs_ops driver_sysfs_ops = {
57 .show = drv_attr_show,
58 .store = drv_attr_store,
59};
60
61
62static void driver_release(struct kobject * kobj)
63{
64 struct device_driver * drv = to_driver(kobj);
65 complete(&drv->unloaded);
66}
67
68static struct kobj_type ktype_driver = {
69 .sysfs_ops = &driver_sysfs_ops,
70 .release = driver_release,
71};
72
73
74/*
75 * sysfs bindings for buses
76 */
77
78
79static ssize_t
80bus_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
81{
82 struct bus_attribute * bus_attr = to_bus_attr(attr);
83 struct bus_type * bus = to_bus(kobj);
84 ssize_t ret = 0;
85
86 if (bus_attr->show)
87 ret = bus_attr->show(bus, buf);
88 return ret;
89}
90
91static ssize_t
92bus_attr_store(struct kobject * kobj, struct attribute * attr,
93 const char * buf, size_t count)
94{
95 struct bus_attribute * bus_attr = to_bus_attr(attr);
96 struct bus_type * bus = to_bus(kobj);
97 ssize_t ret = 0;
98
99 if (bus_attr->store)
100 ret = bus_attr->store(bus, buf, count);
101 return ret;
102}
103
104static struct sysfs_ops bus_sysfs_ops = {
105 .show = bus_attr_show,
106 .store = bus_attr_store,
107};
108
109int bus_create_file(struct bus_type * bus, struct bus_attribute * attr)
110{
111 int error;
112 if (get_bus(bus)) {
113 error = sysfs_create_file(&bus->subsys.kset.kobj, &attr->attr);
114 put_bus(bus);
115 } else
116 error = -EINVAL;
117 return error;
118}
119
120void bus_remove_file(struct bus_type * bus, struct bus_attribute * attr)
121{
122 if (get_bus(bus)) {
123 sysfs_remove_file(&bus->subsys.kset.kobj, &attr->attr);
124 put_bus(bus);
125 }
126}
127
128static struct kobj_type ktype_bus = {
129 .sysfs_ops = &bus_sysfs_ops,
130
131};
132
133decl_subsys(bus, &ktype_bus, NULL);
134
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
Alan Stern2b08c8d2005-11-23 15:43:50 -0800136/* Manually detach a device from its associated driver. */
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700137static int driver_helper(struct device *dev, void *data)
138{
139 const char *name = data;
140
141 if (strcmp(name, dev->bus_id) == 0)
142 return 1;
143 return 0;
144}
145
146static ssize_t driver_unbind(struct device_driver *drv,
147 const char *buf, size_t count)
148{
149 struct bus_type *bus = get_bus(drv->bus);
150 struct device *dev;
151 int err = -ENODEV;
152
153 dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
Alan Stern2b08c8d2005-11-23 15:43:50 -0800154 if (dev && dev->driver == drv) {
Alan Sternbf74ad52005-11-17 16:54:12 -0500155 if (dev->parent) /* Needed for USB */
156 down(&dev->parent->sem);
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700157 device_release_driver(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500158 if (dev->parent)
159 up(&dev->parent->sem);
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700160 err = count;
161 }
Alan Stern2b08c8d2005-11-23 15:43:50 -0800162 put_device(dev);
163 put_bus(bus);
164 return err;
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700165}
166static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind);
167
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700168/*
169 * Manually attach a device to a driver.
170 * Note: the driver must want to bind to the device,
171 * it is not possible to override the driver's id table.
172 */
173static ssize_t driver_bind(struct device_driver *drv,
174 const char *buf, size_t count)
175{
176 struct bus_type *bus = get_bus(drv->bus);
177 struct device *dev;
178 int err = -ENODEV;
179
180 dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
Alan Stern2b08c8d2005-11-23 15:43:50 -0800181 if (dev && dev->driver == NULL) {
Alan Sternbf74ad52005-11-17 16:54:12 -0500182 if (dev->parent) /* Needed for USB */
183 down(&dev->parent->sem);
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700184 down(&dev->sem);
185 err = driver_probe_device(drv, dev);
186 up(&dev->sem);
Alan Sternbf74ad52005-11-17 16:54:12 -0500187 if (dev->parent)
188 up(&dev->parent->sem);
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700189 }
Alan Stern2b08c8d2005-11-23 15:43:50 -0800190 put_device(dev);
191 put_bus(bus);
192 return err;
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700193}
194static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind);
195
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700196
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800197static struct device * next_device(struct klist_iter * i)
198{
199 struct klist_node * n = klist_next(i);
200 return n ? container_of(n, struct device, knode_bus) : NULL;
201}
202
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203/**
204 * bus_for_each_dev - device iterator.
205 * @bus: bus type.
206 * @start: device to start iterating from.
207 * @data: data for the callback.
208 * @fn: function to be called for each device.
209 *
210 * Iterate over @bus's list of devices, and call @fn for each,
211 * passing it @data. If @start is not NULL, we use that device to
212 * begin iterating from.
213 *
214 * We check the return of @fn each time. If it returns anything
215 * other than 0, we break out and return that value.
216 *
217 * NOTE: The device that returns a non-zero value is not retained
218 * in any way, nor is its refcount incremented. If the caller needs
219 * to retain this data, it should do, and increment the reference
220 * count in the supplied callback.
221 */
222
223int bus_for_each_dev(struct bus_type * bus, struct device * start,
224 void * data, int (*fn)(struct device *, void *))
225{
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800226 struct klist_iter i;
227 struct device * dev;
228 int error = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800230 if (!bus)
231 return -EINVAL;
232
233 klist_iter_init_node(&bus->klist_devices, &i,
234 (start ? &start->knode_bus : NULL));
235 while ((dev = next_device(&i)) && !error)
236 error = fn(dev, data);
237 klist_iter_exit(&i);
238 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239}
240
Cornelia Huck0edb5862005-06-22 16:59:51 +0200241/**
242 * bus_find_device - device iterator for locating a particular device.
243 * @bus: bus type
244 * @start: Device to begin with
245 * @data: Data to pass to match function
246 * @match: Callback function to check device
247 *
248 * This is similar to the bus_for_each_dev() function above, but it
249 * returns a reference to a device that is 'found' for later use, as
250 * determined by the @match callback.
251 *
252 * The callback should return 0 if the device doesn't match and non-zero
253 * if it does. If the callback returns non-zero, this function will
254 * return to the caller and not iterate over any more devices.
255 */
256struct device * bus_find_device(struct bus_type *bus,
257 struct device *start, void *data,
258 int (*match)(struct device *, void *))
259{
260 struct klist_iter i;
261 struct device *dev;
262
263 if (!bus)
264 return NULL;
265
266 klist_iter_init_node(&bus->klist_devices, &i,
267 (start ? &start->knode_bus : NULL));
268 while ((dev = next_device(&i)))
269 if (match(dev, data) && get_device(dev))
270 break;
271 klist_iter_exit(&i);
272 return dev;
273}
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800274
275
276static struct device_driver * next_driver(struct klist_iter * i)
277{
278 struct klist_node * n = klist_next(i);
279 return n ? container_of(n, struct device_driver, knode_bus) : NULL;
280}
281
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282/**
283 * bus_for_each_drv - driver iterator
284 * @bus: bus we're dealing with.
285 * @start: driver to start iterating on.
286 * @data: data to pass to the callback.
287 * @fn: function to call for each driver.
288 *
289 * This is nearly identical to the device iterator above.
290 * We iterate over each driver that belongs to @bus, and call
291 * @fn for each. If @fn returns anything but 0, we break out
292 * and return it. If @start is not NULL, we use it as the head
293 * of the list.
294 *
295 * NOTE: we don't return the driver that returns a non-zero
296 * value, nor do we leave the reference count incremented for that
297 * driver. If the caller needs to know that info, it must set it
298 * in the callback. It must also be sure to increment the refcount
299 * so it doesn't disappear before returning to the caller.
300 */
301
302int bus_for_each_drv(struct bus_type * bus, struct device_driver * start,
303 void * data, int (*fn)(struct device_driver *, void *))
304{
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800305 struct klist_iter i;
306 struct device_driver * drv;
307 int error = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800309 if (!bus)
310 return -EINVAL;
311
312 klist_iter_init_node(&bus->klist_drivers, &i,
313 start ? &start->knode_bus : NULL);
314 while ((drv = next_driver(&i)) && !error)
315 error = fn(drv, data);
316 klist_iter_exit(&i);
317 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318}
319
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320static int device_add_attrs(struct bus_type * bus, struct device * dev)
321{
322 int error = 0;
323 int i;
324
325 if (bus->dev_attrs) {
326 for (i = 0; attr_name(bus->dev_attrs[i]); i++) {
327 error = device_create_file(dev,&bus->dev_attrs[i]);
328 if (error)
329 goto Err;
330 }
331 }
332 Done:
333 return error;
334 Err:
335 while (--i >= 0)
336 device_remove_file(dev,&bus->dev_attrs[i]);
337 goto Done;
338}
339
340
341static void device_remove_attrs(struct bus_type * bus, struct device * dev)
342{
343 int i;
344
345 if (bus->dev_attrs) {
346 for (i = 0; attr_name(bus->dev_attrs[i]); i++)
347 device_remove_file(dev,&bus->dev_attrs[i]);
348 }
349}
350
351
352/**
353 * bus_add_device - add device to bus
354 * @dev: device being added
355 *
356 * - Add the device to its bus's list of devices.
357 * - Try to attach to driver.
358 * - Create link to device's physical location.
359 */
360int bus_add_device(struct device * dev)
361{
362 struct bus_type * bus = get_bus(dev->bus);
363 int error = 0;
364
365 if (bus) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id);
Greg Kroah-Hartmand377e852005-06-22 16:09:05 -0700367 device_attach(dev);
James Bottomleyd856f1e32005-08-19 09:14:01 -0400368 klist_add_tail(&dev->knode_bus, &bus->klist_devices);
Greg Kroah-Hartmand377e852005-06-22 16:09:05 -0700369 error = device_add_attrs(bus, dev);
Hannes Reineckeca2b94b2005-05-18 10:42:23 +0200370 if (!error) {
371 sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id);
372 sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus");
373 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 }
375 return error;
376}
377
378/**
379 * bus_remove_device - remove device from bus
380 * @dev: device to be removed
381 *
382 * - Remove symlink from bus's directory.
383 * - Delete device from bus's list.
384 * - Detach from its driver.
385 * - Drop reference taken in bus_add_device().
386 */
387void bus_remove_device(struct device * dev)
388{
389 if (dev->bus) {
390 sysfs_remove_link(&dev->kobj, "bus");
391 sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id);
392 device_remove_attrs(dev->bus, dev);
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800393 klist_remove(&dev->knode_bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 pr_debug("bus %s: remove device %s\n", dev->bus->name, dev->bus_id);
395 device_release_driver(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 put_bus(dev->bus);
397 }
398}
399
400static int driver_add_attrs(struct bus_type * bus, struct device_driver * drv)
401{
402 int error = 0;
403 int i;
404
405 if (bus->drv_attrs) {
406 for (i = 0; attr_name(bus->drv_attrs[i]); i++) {
407 error = driver_create_file(drv, &bus->drv_attrs[i]);
408 if (error)
409 goto Err;
410 }
411 }
412 Done:
413 return error;
414 Err:
415 while (--i >= 0)
416 driver_remove_file(drv, &bus->drv_attrs[i]);
417 goto Done;
418}
419
420
421static void driver_remove_attrs(struct bus_type * bus, struct device_driver * drv)
422{
423 int i;
424
425 if (bus->drv_attrs) {
426 for (i = 0; attr_name(bus->drv_attrs[i]); i++)
427 driver_remove_file(drv, &bus->drv_attrs[i]);
428 }
429}
430
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800431#ifdef CONFIG_HOTPLUG
432/*
433 * Thanks to drivers making their tables __devinit, we can't allow manual
434 * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled.
435 */
436static void add_bind_files(struct device_driver *drv)
437{
438 driver_create_file(drv, &driver_attr_unbind);
439 driver_create_file(drv, &driver_attr_bind);
440}
441
442static void remove_bind_files(struct device_driver *drv)
443{
444 driver_remove_file(drv, &driver_attr_bind);
445 driver_remove_file(drv, &driver_attr_unbind);
446}
447#else
448static inline void add_bind_files(struct device_driver *drv) {}
449static inline void remove_bind_files(struct device_driver *drv) {}
450#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
452/**
453 * bus_add_driver - Add a driver to the bus.
454 * @drv: driver.
455 *
456 */
457int bus_add_driver(struct device_driver * drv)
458{
459 struct bus_type * bus = get_bus(drv->bus);
460 int error = 0;
461
462 if (bus) {
463 pr_debug("bus %s: add driver %s\n", bus->name, drv->name);
464 error = kobject_set_name(&drv->kobj, "%s", drv->name);
465 if (error) {
466 put_bus(bus);
467 return error;
468 }
469 drv->kobj.kset = &bus->drivers;
470 if ((error = kobject_register(&drv->kobj))) {
471 put_bus(bus);
472 return error;
473 }
474
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 driver_attach(drv);
James Bottomleyd856f1e32005-08-19 09:14:01 -0400476 klist_add_tail(&drv->knode_bus, &bus->klist_drivers);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477 module_add_driver(drv->owner, drv);
478
479 driver_add_attrs(bus, drv);
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800480 add_bind_files(drv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 }
482 return error;
483}
484
485
486/**
487 * bus_remove_driver - delete driver from bus's knowledge.
488 * @drv: driver.
489 *
490 * Detach the driver from the devices it controls, and remove
491 * it from its bus's list of drivers. Finally, we drop the reference
492 * to the bus we took in bus_add_driver().
493 */
494
495void bus_remove_driver(struct device_driver * drv)
496{
497 if (drv->bus) {
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800498 remove_bind_files(drv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 driver_remove_attrs(drv->bus, drv);
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800500 klist_remove(&drv->knode_bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name);
502 driver_detach(drv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 module_remove_driver(drv);
504 kobject_unregister(&drv->kobj);
505 put_bus(drv->bus);
506 }
507}
508
509
510/* Helper for bus_rescan_devices's iter */
511static int bus_rescan_devices_helper(struct device *dev, void *data)
512{
Alan Sternbf74ad52005-11-17 16:54:12 -0500513 if (!dev->driver) {
514 if (dev->parent) /* Needed for USB */
515 down(&dev->parent->sem);
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700516 device_attach(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500517 if (dev->parent)
518 up(&dev->parent->sem);
519 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 return 0;
521}
522
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523/**
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700524 * bus_rescan_devices - rescan devices on the bus for possible drivers
525 * @bus: the bus to scan.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 *
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700527 * This function will look for devices on the bus with no driver
528 * attached and rescan it against existing drivers to see if it matches
529 * any by calling device_attach() for the unbound devices.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 */
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700531void bus_rescan_devices(struct bus_type * bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532{
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700533 bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534}
535
536
537struct bus_type * get_bus(struct bus_type * bus)
538{
539 return bus ? container_of(subsys_get(&bus->subsys), struct bus_type, subsys) : NULL;
540}
541
542void put_bus(struct bus_type * bus)
543{
544 subsys_put(&bus->subsys);
545}
546
547
548/**
549 * find_bus - locate bus by name.
550 * @name: name of bus.
551 *
552 * Call kset_find_obj() to iterate over list of buses to
553 * find a bus by name. Return bus if found.
554 *
555 * Note that kset_find_obj increments bus' reference count.
556 */
557
558struct bus_type * find_bus(char * name)
559{
560 struct kobject * k = kset_find_obj(&bus_subsys.kset, name);
561 return k ? to_bus(k) : NULL;
562}
563
564
565/**
566 * bus_add_attrs - Add default attributes for this bus.
567 * @bus: Bus that has just been registered.
568 */
569
570static int bus_add_attrs(struct bus_type * bus)
571{
572 int error = 0;
573 int i;
574
575 if (bus->bus_attrs) {
576 for (i = 0; attr_name(bus->bus_attrs[i]); i++) {
577 if ((error = bus_create_file(bus,&bus->bus_attrs[i])))
578 goto Err;
579 }
580 }
581 Done:
582 return error;
583 Err:
584 while (--i >= 0)
585 bus_remove_file(bus,&bus->bus_attrs[i]);
586 goto Done;
587}
588
589static void bus_remove_attrs(struct bus_type * bus)
590{
591 int i;
592
593 if (bus->bus_attrs) {
594 for (i = 0; attr_name(bus->bus_attrs[i]); i++)
595 bus_remove_file(bus,&bus->bus_attrs[i]);
596 }
597}
598
James Bottomley34bb61f2005-09-06 16:56:51 -0700599static void klist_devices_get(struct klist_node *n)
600{
601 struct device *dev = container_of(n, struct device, knode_bus);
602
603 get_device(dev);
604}
605
606static void klist_devices_put(struct klist_node *n)
607{
608 struct device *dev = container_of(n, struct device, knode_bus);
609
610 put_device(dev);
611}
612
613static void klist_drivers_get(struct klist_node *n)
614{
615 struct device_driver *drv = container_of(n, struct device_driver,
616 knode_bus);
617
618 get_driver(drv);
619}
620
621static void klist_drivers_put(struct klist_node *n)
622{
623 struct device_driver *drv = container_of(n, struct device_driver,
624 knode_bus);
625
626 put_driver(drv);
627}
628
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629/**
630 * bus_register - register a bus with the system.
631 * @bus: bus.
632 *
633 * Once we have that, we registered the bus with the kobject
634 * infrastructure, then register the children subsystems it has:
635 * the devices and drivers that belong to the bus.
636 */
637int bus_register(struct bus_type * bus)
638{
639 int retval;
640
641 retval = kobject_set_name(&bus->subsys.kset.kobj, "%s", bus->name);
642 if (retval)
643 goto out;
644
645 subsys_set_kset(bus, bus_subsys);
646 retval = subsystem_register(&bus->subsys);
647 if (retval)
648 goto out;
649
650 kobject_set_name(&bus->devices.kobj, "devices");
651 bus->devices.subsys = &bus->subsys;
652 retval = kset_register(&bus->devices);
653 if (retval)
654 goto bus_devices_fail;
655
656 kobject_set_name(&bus->drivers.kobj, "drivers");
657 bus->drivers.subsys = &bus->subsys;
658 bus->drivers.ktype = &ktype_driver;
659 retval = kset_register(&bus->drivers);
660 if (retval)
661 goto bus_drivers_fail;
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800662
James Bottomley34bb61f2005-09-06 16:56:51 -0700663 klist_init(&bus->klist_devices, klist_devices_get, klist_devices_put);
664 klist_init(&bus->klist_drivers, klist_drivers_get, klist_drivers_put);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 bus_add_attrs(bus);
666
667 pr_debug("bus type '%s' registered\n", bus->name);
668 return 0;
669
670bus_drivers_fail:
671 kset_unregister(&bus->devices);
672bus_devices_fail:
673 subsystem_unregister(&bus->subsys);
674out:
675 return retval;
676}
677
678
679/**
680 * bus_unregister - remove a bus from the system
681 * @bus: bus.
682 *
683 * Unregister the child subsystems and the bus itself.
684 * Finally, we call put_bus() to release the refcount
685 */
686void bus_unregister(struct bus_type * bus)
687{
688 pr_debug("bus %s: unregistering\n", bus->name);
689 bus_remove_attrs(bus);
690 kset_unregister(&bus->drivers);
691 kset_unregister(&bus->devices);
692 subsystem_unregister(&bus->subsys);
693}
694
695int __init buses_init(void)
696{
697 return subsystem_register(&bus_subsys);
698}
699
700
701EXPORT_SYMBOL_GPL(bus_for_each_dev);
Cornelia Huck0edb5862005-06-22 16:59:51 +0200702EXPORT_SYMBOL_GPL(bus_find_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703EXPORT_SYMBOL_GPL(bus_for_each_drv);
704
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705EXPORT_SYMBOL_GPL(bus_add_device);
706EXPORT_SYMBOL_GPL(bus_remove_device);
707EXPORT_SYMBOL_GPL(bus_register);
708EXPORT_SYMBOL_GPL(bus_unregister);
709EXPORT_SYMBOL_GPL(bus_rescan_devices);
710EXPORT_SYMBOL_GPL(get_bus);
711EXPORT_SYMBOL_GPL(put_bus);
712EXPORT_SYMBOL_GPL(find_bus);
713
714EXPORT_SYMBOL_GPL(bus_create_file);
715EXPORT_SYMBOL_GPL(bus_remove_file);