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11#include <linux/async.h>
12#include <linux/device/bus.h>
13#include <linux/device.h>
14#include <linux/module.h>
15#include <linux/errno.h>
16#include <linux/slab.h>
17#include <linux/init.h>
18#include <linux/string.h>
19#include <linux/mutex.h>
20#include <linux/sysfs.h>
21#include "base.h"
22#include "power/power.h"
23
24
25static struct kset *system_kset;
26
27#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)
28
29
30
31
32
33#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)
34
35#define DRIVER_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
36 struct driver_attribute driver_attr_##_name = \
37 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
38
39static int __must_check bus_rescan_devices_helper(struct device *dev,
40 void *data);
41
42static struct bus_type *bus_get(struct bus_type *bus)
43{
44 if (bus) {
45 kset_get(&bus->p->subsys);
46 return bus;
47 }
48 return NULL;
49}
50
51static void bus_put(struct bus_type *bus)
52{
53 if (bus)
54 kset_put(&bus->p->subsys);
55}
56
57static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr,
58 char *buf)
59{
60 struct driver_attribute *drv_attr = to_drv_attr(attr);
61 struct driver_private *drv_priv = to_driver(kobj);
62 ssize_t ret = -EIO;
63
64 if (drv_attr->show)
65 ret = drv_attr->show(drv_priv->driver, buf);
66 return ret;
67}
68
69static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr,
70 const char *buf, size_t count)
71{
72 struct driver_attribute *drv_attr = to_drv_attr(attr);
73 struct driver_private *drv_priv = to_driver(kobj);
74 ssize_t ret = -EIO;
75
76 if (drv_attr->store)
77 ret = drv_attr->store(drv_priv->driver, buf, count);
78 return ret;
79}
80
81static const struct sysfs_ops driver_sysfs_ops = {
82 .show = drv_attr_show,
83 .store = drv_attr_store,
84};
85
86static void driver_release(struct kobject *kobj)
87{
88 struct driver_private *drv_priv = to_driver(kobj);
89
90 pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__);
91 kfree(drv_priv);
92}
93
94static struct kobj_type driver_ktype = {
95 .sysfs_ops = &driver_sysfs_ops,
96 .release = driver_release,
97};
98
99
100
101
102static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr,
103 char *buf)
104{
105 struct bus_attribute *bus_attr = to_bus_attr(attr);
106 struct subsys_private *subsys_priv = to_subsys_private(kobj);
107 ssize_t ret = 0;
108
109 if (bus_attr->show)
110 ret = bus_attr->show(subsys_priv->bus, buf);
111 return ret;
112}
113
114static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr,
115 const char *buf, size_t count)
116{
117 struct bus_attribute *bus_attr = to_bus_attr(attr);
118 struct subsys_private *subsys_priv = to_subsys_private(kobj);
119 ssize_t ret = 0;
120
121 if (bus_attr->store)
122 ret = bus_attr->store(subsys_priv->bus, buf, count);
123 return ret;
124}
125
126static const struct sysfs_ops bus_sysfs_ops = {
127 .show = bus_attr_show,
128 .store = bus_attr_store,
129};
130
131int bus_create_file(struct bus_type *bus, struct bus_attribute *attr)
132{
133 int error;
134 if (bus_get(bus)) {
135 error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr);
136 bus_put(bus);
137 } else
138 error = -EINVAL;
139 return error;
140}
141EXPORT_SYMBOL_GPL(bus_create_file);
142
143void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr)
144{
145 if (bus_get(bus)) {
146 sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr);
147 bus_put(bus);
148 }
149}
150EXPORT_SYMBOL_GPL(bus_remove_file);
151
152static void bus_release(struct kobject *kobj)
153{
154 struct subsys_private *priv = to_subsys_private(kobj);
155 struct bus_type *bus = priv->bus;
156
157 kfree(priv);
158 bus->p = NULL;
159}
160
161static struct kobj_type bus_ktype = {
162 .sysfs_ops = &bus_sysfs_ops,
163 .release = bus_release,
164};
165
166static int bus_uevent_filter(struct kset *kset, struct kobject *kobj)
167{
168 struct kobj_type *ktype = get_ktype(kobj);
169
170 if (ktype == &bus_ktype)
171 return 1;
172 return 0;
173}
174
175static const struct kset_uevent_ops bus_uevent_ops = {
176 .filter = bus_uevent_filter,
177};
178
179static struct kset *bus_kset;
180
181
182static ssize_t unbind_store(struct device_driver *drv, const char *buf,
183 size_t count)
184{
185 struct bus_type *bus = bus_get(drv->bus);
186 struct device *dev;
187 int err = -ENODEV;
188
189 dev = bus_find_device_by_name(bus, NULL, buf);
190 if (dev && dev->driver == drv) {
191 device_driver_detach(dev);
192 err = count;
193 }
194 put_device(dev);
195 bus_put(bus);
196 return err;
197}
198static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store);
199
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202
203
204
205static ssize_t bind_store(struct device_driver *drv, const char *buf,
206 size_t count)
207{
208 struct bus_type *bus = bus_get(drv->bus);
209 struct device *dev;
210 int err = -ENODEV;
211
212 dev = bus_find_device_by_name(bus, NULL, buf);
213 if (dev && driver_match_device(drv, dev)) {
214 err = device_driver_attach(drv, dev);
215 if (!err) {
216
217 err = count;
218 }
219 }
220 put_device(dev);
221 bus_put(bus);
222 return err;
223}
224static DRIVER_ATTR_IGNORE_LOCKDEP(bind, 0200, NULL, bind_store);
225
226static ssize_t drivers_autoprobe_show(struct bus_type *bus, char *buf)
227{
228 return sysfs_emit(buf, "%d\n", bus->p->drivers_autoprobe);
229}
230
231static ssize_t drivers_autoprobe_store(struct bus_type *bus,
232 const char *buf, size_t count)
233{
234 if (buf[0] == '0')
235 bus->p->drivers_autoprobe = 0;
236 else
237 bus->p->drivers_autoprobe = 1;
238 return count;
239}
240
241static ssize_t drivers_probe_store(struct bus_type *bus,
242 const char *buf, size_t count)
243{
244 struct device *dev;
245 int err = -EINVAL;
246
247 dev = bus_find_device_by_name(bus, NULL, buf);
248 if (!dev)
249 return -ENODEV;
250 if (bus_rescan_devices_helper(dev, NULL) == 0)
251 err = count;
252 put_device(dev);
253 return err;
254}
255
256static struct device *next_device(struct klist_iter *i)
257{
258 struct klist_node *n = klist_next(i);
259 struct device *dev = NULL;
260 struct device_private *dev_prv;
261
262 if (n) {
263 dev_prv = to_device_private_bus(n);
264 dev = dev_prv->device;
265 }
266 return dev;
267}
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288int bus_for_each_dev(struct bus_type *bus, struct device *start,
289 void *data, int (*fn)(struct device *, void *))
290{
291 struct klist_iter i;
292 struct device *dev;
293 int error = 0;
294
295 if (!bus || !bus->p)
296 return -EINVAL;
297
298 klist_iter_init_node(&bus->p->klist_devices, &i,
299 (start ? &start->p->knode_bus : NULL));
300 while (!error && (dev = next_device(&i)))
301 error = fn(dev, data);
302 klist_iter_exit(&i);
303 return error;
304}
305EXPORT_SYMBOL_GPL(bus_for_each_dev);
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321
322struct device *bus_find_device(struct bus_type *bus,
323 struct device *start, const void *data,
324 int (*match)(struct device *dev, const void *data))
325{
326 struct klist_iter i;
327 struct device *dev;
328
329 if (!bus || !bus->p)
330 return NULL;
331
332 klist_iter_init_node(&bus->p->klist_devices, &i,
333 (start ? &start->p->knode_bus : NULL));
334 while ((dev = next_device(&i)))
335 if (match(dev, data) && get_device(dev))
336 break;
337 klist_iter_exit(&i);
338 return dev;
339}
340EXPORT_SYMBOL_GPL(bus_find_device);
341
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350
351
352struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id,
353 struct device *hint)
354{
355 struct klist_iter i;
356 struct device *dev;
357
358 if (!subsys)
359 return NULL;
360
361 if (hint) {
362 klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus);
363 dev = next_device(&i);
364 if (dev && dev->id == id && get_device(dev)) {
365 klist_iter_exit(&i);
366 return dev;
367 }
368 klist_iter_exit(&i);
369 }
370
371 klist_iter_init_node(&subsys->p->klist_devices, &i, NULL);
372 while ((dev = next_device(&i))) {
373 if (dev->id == id && get_device(dev)) {
374 klist_iter_exit(&i);
375 return dev;
376 }
377 }
378 klist_iter_exit(&i);
379 return NULL;
380}
381EXPORT_SYMBOL_GPL(subsys_find_device_by_id);
382
383static struct device_driver *next_driver(struct klist_iter *i)
384{
385 struct klist_node *n = klist_next(i);
386 struct driver_private *drv_priv;
387
388 if (n) {
389 drv_priv = container_of(n, struct driver_private, knode_bus);
390 return drv_priv->driver;
391 }
392 return NULL;
393}
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413
414int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
415 void *data, int (*fn)(struct device_driver *, void *))
416{
417 struct klist_iter i;
418 struct device_driver *drv;
419 int error = 0;
420
421 if (!bus)
422 return -EINVAL;
423
424 klist_iter_init_node(&bus->p->klist_drivers, &i,
425 start ? &start->p->knode_bus : NULL);
426 while ((drv = next_driver(&i)) && !error)
427 error = fn(drv, data);
428 klist_iter_exit(&i);
429 return error;
430}
431EXPORT_SYMBOL_GPL(bus_for_each_drv);
432
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439
440
441int bus_add_device(struct device *dev)
442{
443 struct bus_type *bus = bus_get(dev->bus);
444 int error = 0;
445
446 if (bus) {
447 pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev));
448 error = device_add_groups(dev, bus->dev_groups);
449 if (error)
450 goto out_put;
451 error = sysfs_create_link(&bus->p->devices_kset->kobj,
452 &dev->kobj, dev_name(dev));
453 if (error)
454 goto out_groups;
455 error = sysfs_create_link(&dev->kobj,
456 &dev->bus->p->subsys.kobj, "subsystem");
457 if (error)
458 goto out_subsys;
459 klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
460 }
461 return 0;
462
463out_subsys:
464 sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
465out_groups:
466 device_remove_groups(dev, bus->dev_groups);
467out_put:
468 bus_put(dev->bus);
469 return error;
470}
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476
477
478void bus_probe_device(struct device *dev)
479{
480 struct bus_type *bus = dev->bus;
481 struct subsys_interface *sif;
482
483 if (!bus)
484 return;
485
486 if (bus->p->drivers_autoprobe)
487 device_initial_probe(dev);
488
489 mutex_lock(&bus->p->mutex);
490 list_for_each_entry(sif, &bus->p->interfaces, node)
491 if (sif->add_dev)
492 sif->add_dev(dev, sif);
493 mutex_unlock(&bus->p->mutex);
494}
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505
506void bus_remove_device(struct device *dev)
507{
508 struct bus_type *bus = dev->bus;
509 struct subsys_interface *sif;
510
511 if (!bus)
512 return;
513
514 mutex_lock(&bus->p->mutex);
515 list_for_each_entry(sif, &bus->p->interfaces, node)
516 if (sif->remove_dev)
517 sif->remove_dev(dev, sif);
518 mutex_unlock(&bus->p->mutex);
519
520 sysfs_remove_link(&dev->kobj, "subsystem");
521 sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
522 dev_name(dev));
523 device_remove_groups(dev, dev->bus->dev_groups);
524 if (klist_node_attached(&dev->p->knode_bus))
525 klist_del(&dev->p->knode_bus);
526
527 pr_debug("bus: '%s': remove device %s\n",
528 dev->bus->name, dev_name(dev));
529 device_release_driver(dev);
530 bus_put(dev->bus);
531}
532
533static int __must_check add_bind_files(struct device_driver *drv)
534{
535 int ret;
536
537 ret = driver_create_file(drv, &driver_attr_unbind);
538 if (ret == 0) {
539 ret = driver_create_file(drv, &driver_attr_bind);
540 if (ret)
541 driver_remove_file(drv, &driver_attr_unbind);
542 }
543 return ret;
544}
545
546static void remove_bind_files(struct device_driver *drv)
547{
548 driver_remove_file(drv, &driver_attr_bind);
549 driver_remove_file(drv, &driver_attr_unbind);
550}
551
552static BUS_ATTR_WO(drivers_probe);
553static BUS_ATTR_RW(drivers_autoprobe);
554
555static int add_probe_files(struct bus_type *bus)
556{
557 int retval;
558
559 retval = bus_create_file(bus, &bus_attr_drivers_probe);
560 if (retval)
561 goto out;
562
563 retval = bus_create_file(bus, &bus_attr_drivers_autoprobe);
564 if (retval)
565 bus_remove_file(bus, &bus_attr_drivers_probe);
566out:
567 return retval;
568}
569
570static void remove_probe_files(struct bus_type *bus)
571{
572 bus_remove_file(bus, &bus_attr_drivers_autoprobe);
573 bus_remove_file(bus, &bus_attr_drivers_probe);
574}
575
576static ssize_t uevent_store(struct device_driver *drv, const char *buf,
577 size_t count)
578{
579 int rc;
580
581 rc = kobject_synth_uevent(&drv->p->kobj, buf, count);
582 return rc ? rc : count;
583}
584static DRIVER_ATTR_WO(uevent);
585
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589
590int bus_add_driver(struct device_driver *drv)
591{
592 struct bus_type *bus;
593 struct driver_private *priv;
594 int error = 0;
595
596 bus = bus_get(drv->bus);
597 if (!bus)
598 return -EINVAL;
599
600 pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);
601
602 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
603 if (!priv) {
604 error = -ENOMEM;
605 goto out_put_bus;
606 }
607 klist_init(&priv->klist_devices, NULL, NULL);
608 priv->driver = drv;
609 drv->p = priv;
610 priv->kobj.kset = bus->p->drivers_kset;
611 error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,
612 "%s", drv->name);
613 if (error)
614 goto out_unregister;
615
616 klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);
617 if (drv->bus->p->drivers_autoprobe) {
618 error = driver_attach(drv);
619 if (error)
620 goto out_unregister;
621 }
622 module_add_driver(drv->owner, drv);
623
624 error = driver_create_file(drv, &driver_attr_uevent);
625 if (error) {
626 printk(KERN_ERR "%s: uevent attr (%s) failed\n",
627 __func__, drv->name);
628 }
629 error = driver_add_groups(drv, bus->drv_groups);
630 if (error) {
631
632 printk(KERN_ERR "%s: driver_add_groups(%s) failed\n",
633 __func__, drv->name);
634 }
635
636 if (!drv->suppress_bind_attrs) {
637 error = add_bind_files(drv);
638 if (error) {
639
640 printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
641 __func__, drv->name);
642 }
643 }
644
645 return 0;
646
647out_unregister:
648 kobject_put(&priv->kobj);
649
650 drv->p = NULL;
651out_put_bus:
652 bus_put(bus);
653 return error;
654}
655
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657
658
659
660
661
662
663
664void bus_remove_driver(struct device_driver *drv)
665{
666 if (!drv->bus)
667 return;
668
669 if (!drv->suppress_bind_attrs)
670 remove_bind_files(drv);
671 driver_remove_groups(drv, drv->bus->drv_groups);
672 driver_remove_file(drv, &driver_attr_uevent);
673 klist_remove(&drv->p->knode_bus);
674 pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name);
675 driver_detach(drv);
676 module_remove_driver(drv);
677 kobject_put(&drv->p->kobj);
678 bus_put(drv->bus);
679}
680
681
682static int __must_check bus_rescan_devices_helper(struct device *dev,
683 void *data)
684{
685 int ret = 0;
686
687 if (!dev->driver) {
688 if (dev->parent && dev->bus->need_parent_lock)
689 device_lock(dev->parent);
690 ret = device_attach(dev);
691 if (dev->parent && dev->bus->need_parent_lock)
692 device_unlock(dev->parent);
693 }
694 return ret < 0 ? ret : 0;
695}
696
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698
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700
701
702
703
704
705int bus_rescan_devices(struct bus_type *bus)
706{
707 return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper);
708}
709EXPORT_SYMBOL_GPL(bus_rescan_devices);
710
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716
717
718
719
720int device_reprobe(struct device *dev)
721{
722 if (dev->driver)
723 device_driver_detach(dev);
724 return bus_rescan_devices_helper(dev, NULL);
725}
726EXPORT_SYMBOL_GPL(device_reprobe);
727
728static int bus_add_groups(struct bus_type *bus,
729 const struct attribute_group **groups)
730{
731 return sysfs_create_groups(&bus->p->subsys.kobj, groups);
732}
733
734static void bus_remove_groups(struct bus_type *bus,
735 const struct attribute_group **groups)
736{
737 sysfs_remove_groups(&bus->p->subsys.kobj, groups);
738}
739
740static void klist_devices_get(struct klist_node *n)
741{
742 struct device_private *dev_prv = to_device_private_bus(n);
743 struct device *dev = dev_prv->device;
744
745 get_device(dev);
746}
747
748static void klist_devices_put(struct klist_node *n)
749{
750 struct device_private *dev_prv = to_device_private_bus(n);
751 struct device *dev = dev_prv->device;
752
753 put_device(dev);
754}
755
756static ssize_t bus_uevent_store(struct bus_type *bus,
757 const char *buf, size_t count)
758{
759 int rc;
760
761 rc = kobject_synth_uevent(&bus->p->subsys.kobj, buf, count);
762 return rc ? rc : count;
763}
764
765
766
767
768
769
770static struct bus_attribute bus_attr_uevent = __ATTR(uevent, 0200, NULL,
771 bus_uevent_store);
772
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779
780
781int bus_register(struct bus_type *bus)
782{
783 int retval;
784 struct subsys_private *priv;
785 struct lock_class_key *key = &bus->lock_key;
786
787 priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL);
788 if (!priv)
789 return -ENOMEM;
790
791 priv->bus = bus;
792 bus->p = priv;
793
794 BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);
795
796 retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name);
797 if (retval)
798 goto out;
799
800 priv->subsys.kobj.kset = bus_kset;
801 priv->subsys.kobj.ktype = &bus_ktype;
802 priv->drivers_autoprobe = 1;
803
804 retval = kset_register(&priv->subsys);
805 if (retval)
806 goto out;
807
808 retval = bus_create_file(bus, &bus_attr_uevent);
809 if (retval)
810 goto bus_uevent_fail;
811
812 priv->devices_kset = kset_create_and_add("devices", NULL,
813 &priv->subsys.kobj);
814 if (!priv->devices_kset) {
815 retval = -ENOMEM;
816 goto bus_devices_fail;
817 }
818
819 priv->drivers_kset = kset_create_and_add("drivers", NULL,
820 &priv->subsys.kobj);
821 if (!priv->drivers_kset) {
822 retval = -ENOMEM;
823 goto bus_drivers_fail;
824 }
825
826 INIT_LIST_HEAD(&priv->interfaces);
827 __mutex_init(&priv->mutex, "subsys mutex", key);
828 klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put);
829 klist_init(&priv->klist_drivers, NULL, NULL);
830
831 retval = add_probe_files(bus);
832 if (retval)
833 goto bus_probe_files_fail;
834
835 retval = bus_add_groups(bus, bus->bus_groups);
836 if (retval)
837 goto bus_groups_fail;
838
839 pr_debug("bus: '%s': registered\n", bus->name);
840 return 0;
841
842bus_groups_fail:
843 remove_probe_files(bus);
844bus_probe_files_fail:
845 kset_unregister(bus->p->drivers_kset);
846bus_drivers_fail:
847 kset_unregister(bus->p->devices_kset);
848bus_devices_fail:
849 bus_remove_file(bus, &bus_attr_uevent);
850bus_uevent_fail:
851 kset_unregister(&bus->p->subsys);
852out:
853 kfree(bus->p);
854 bus->p = NULL;
855 return retval;
856}
857EXPORT_SYMBOL_GPL(bus_register);
858
859
860
861
862
863
864
865
866void bus_unregister(struct bus_type *bus)
867{
868 pr_debug("bus: '%s': unregistering\n", bus->name);
869 if (bus->dev_root)
870 device_unregister(bus->dev_root);
871 bus_remove_groups(bus, bus->bus_groups);
872 remove_probe_files(bus);
873 kset_unregister(bus->p->drivers_kset);
874 kset_unregister(bus->p->devices_kset);
875 bus_remove_file(bus, &bus_attr_uevent);
876 kset_unregister(&bus->p->subsys);
877}
878EXPORT_SYMBOL_GPL(bus_unregister);
879
880int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb)
881{
882 return blocking_notifier_chain_register(&bus->p->bus_notifier, nb);
883}
884EXPORT_SYMBOL_GPL(bus_register_notifier);
885
886int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb)
887{
888 return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb);
889}
890EXPORT_SYMBOL_GPL(bus_unregister_notifier);
891
892struct kset *bus_get_kset(struct bus_type *bus)
893{
894 return &bus->p->subsys;
895}
896EXPORT_SYMBOL_GPL(bus_get_kset);
897
898struct klist *bus_get_device_klist(struct bus_type *bus)
899{
900 return &bus->p->klist_devices;
901}
902EXPORT_SYMBOL_GPL(bus_get_device_klist);
903
904
905
906
907
908
909
910
911static void device_insertion_sort_klist(struct device *a, struct list_head *list,
912 int (*compare)(const struct device *a,
913 const struct device *b))
914{
915 struct klist_node *n;
916 struct device_private *dev_prv;
917 struct device *b;
918
919 list_for_each_entry(n, list, n_node) {
920 dev_prv = to_device_private_bus(n);
921 b = dev_prv->device;
922 if (compare(a, b) <= 0) {
923 list_move_tail(&a->p->knode_bus.n_node,
924 &b->p->knode_bus.n_node);
925 return;
926 }
927 }
928 list_move_tail(&a->p->knode_bus.n_node, list);
929}
930
931void bus_sort_breadthfirst(struct bus_type *bus,
932 int (*compare)(const struct device *a,
933 const struct device *b))
934{
935 LIST_HEAD(sorted_devices);
936 struct klist_node *n, *tmp;
937 struct device_private *dev_prv;
938 struct device *dev;
939 struct klist *device_klist;
940
941 device_klist = bus_get_device_klist(bus);
942
943 spin_lock(&device_klist->k_lock);
944 list_for_each_entry_safe(n, tmp, &device_klist->k_list, n_node) {
945 dev_prv = to_device_private_bus(n);
946 dev = dev_prv->device;
947 device_insertion_sort_klist(dev, &sorted_devices, compare);
948 }
949 list_splice(&sorted_devices, &device_klist->k_list);
950 spin_unlock(&device_klist->k_lock);
951}
952EXPORT_SYMBOL_GPL(bus_sort_breadthfirst);
953
954
955
956
957
958
959
960
961
962
963
964
965
966void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys,
967 struct device *start, const struct device_type *type)
968{
969 struct klist_node *start_knode = NULL;
970
971 if (start)
972 start_knode = &start->p->knode_bus;
973 klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode);
974 iter->type = type;
975}
976EXPORT_SYMBOL_GPL(subsys_dev_iter_init);
977
978
979
980
981
982
983
984
985
986
987
988
989
990struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter)
991{
992 struct klist_node *knode;
993 struct device *dev;
994
995 for (;;) {
996 knode = klist_next(&iter->ki);
997 if (!knode)
998 return NULL;
999 dev = to_device_private_bus(knode)->device;
1000 if (!iter->type || iter->type == dev->type)
1001 return dev;
1002 }
1003}
1004EXPORT_SYMBOL_GPL(subsys_dev_iter_next);
1005
1006
1007
1008
1009
1010
1011
1012
1013void subsys_dev_iter_exit(struct subsys_dev_iter *iter)
1014{
1015 klist_iter_exit(&iter->ki);
1016}
1017EXPORT_SYMBOL_GPL(subsys_dev_iter_exit);
1018
1019int subsys_interface_register(struct subsys_interface *sif)
1020{
1021 struct bus_type *subsys;
1022 struct subsys_dev_iter iter;
1023 struct device *dev;
1024
1025 if (!sif || !sif->subsys)
1026 return -ENODEV;
1027
1028 subsys = bus_get(sif->subsys);
1029 if (!subsys)
1030 return -EINVAL;
1031
1032 mutex_lock(&subsys->p->mutex);
1033 list_add_tail(&sif->node, &subsys->p->interfaces);
1034 if (sif->add_dev) {
1035 subsys_dev_iter_init(&iter, subsys, NULL, NULL);
1036 while ((dev = subsys_dev_iter_next(&iter)))
1037 sif->add_dev(dev, sif);
1038 subsys_dev_iter_exit(&iter);
1039 }
1040 mutex_unlock(&subsys->p->mutex);
1041
1042 return 0;
1043}
1044EXPORT_SYMBOL_GPL(subsys_interface_register);
1045
1046void subsys_interface_unregister(struct subsys_interface *sif)
1047{
1048 struct bus_type *subsys;
1049 struct subsys_dev_iter iter;
1050 struct device *dev;
1051
1052 if (!sif || !sif->subsys)
1053 return;
1054
1055 subsys = sif->subsys;
1056
1057 mutex_lock(&subsys->p->mutex);
1058 list_del_init(&sif->node);
1059 if (sif->remove_dev) {
1060 subsys_dev_iter_init(&iter, subsys, NULL, NULL);
1061 while ((dev = subsys_dev_iter_next(&iter)))
1062 sif->remove_dev(dev, sif);
1063 subsys_dev_iter_exit(&iter);
1064 }
1065 mutex_unlock(&subsys->p->mutex);
1066
1067 bus_put(subsys);
1068}
1069EXPORT_SYMBOL_GPL(subsys_interface_unregister);
1070
1071static void system_root_device_release(struct device *dev)
1072{
1073 kfree(dev);
1074}
1075
1076static int subsys_register(struct bus_type *subsys,
1077 const struct attribute_group **groups,
1078 struct kobject *parent_of_root)
1079{
1080 struct device *dev;
1081 int err;
1082
1083 err = bus_register(subsys);
1084 if (err < 0)
1085 return err;
1086
1087 dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1088 if (!dev) {
1089 err = -ENOMEM;
1090 goto err_dev;
1091 }
1092
1093 err = dev_set_name(dev, "%s", subsys->name);
1094 if (err < 0)
1095 goto err_name;
1096
1097 dev->kobj.parent = parent_of_root;
1098 dev->groups = groups;
1099 dev->release = system_root_device_release;
1100
1101 err = device_register(dev);
1102 if (err < 0)
1103 goto err_dev_reg;
1104
1105 subsys->dev_root = dev;
1106 return 0;
1107
1108err_dev_reg:
1109 put_device(dev);
1110 dev = NULL;
1111err_name:
1112 kfree(dev);
1113err_dev:
1114 bus_unregister(subsys);
1115 return err;
1116}
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136int subsys_system_register(struct bus_type *subsys,
1137 const struct attribute_group **groups)
1138{
1139 return subsys_register(subsys, groups, &system_kset->kobj);
1140}
1141EXPORT_SYMBOL_GPL(subsys_system_register);
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154int subsys_virtual_register(struct bus_type *subsys,
1155 const struct attribute_group **groups)
1156{
1157 struct kobject *virtual_dir;
1158
1159 virtual_dir = virtual_device_parent(NULL);
1160 if (!virtual_dir)
1161 return -ENOMEM;
1162
1163 return subsys_register(subsys, groups, virtual_dir);
1164}
1165EXPORT_SYMBOL_GPL(subsys_virtual_register);
1166
1167int __init buses_init(void)
1168{
1169 bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL);
1170 if (!bus_kset)
1171 return -ENOMEM;
1172
1173 system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj);
1174 if (!system_kset)
1175 return -ENOMEM;
1176
1177 return 0;
1178}
1179