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13#include <linux/async.h>
14#include <linux/device.h>
15#include <linux/module.h>
16#include <linux/errno.h>
17#include <linux/slab.h>
18#include <linux/init.h>
19#include <linux/string.h>
20#include <linux/mutex.h>
21#include <linux/sysfs.h>
22#include "base.h"
23#include "power/power.h"
24
25
26static struct kset *system_kset;
27
28#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)
29
30
31
32
33
34#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)
35
36
37static int __must_check bus_rescan_devices_helper(struct device *dev,
38 void *data);
39
40static struct bus_type *bus_get(struct bus_type *bus)
41{
42 if (bus) {
43 kset_get(&bus->p->subsys);
44 return bus;
45 }
46 return NULL;
47}
48
49static void bus_put(struct bus_type *bus)
50{
51 if (bus)
52 kset_put(&bus->p->subsys);
53}
54
55static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr,
56 char *buf)
57{
58 struct driver_attribute *drv_attr = to_drv_attr(attr);
59 struct driver_private *drv_priv = to_driver(kobj);
60 ssize_t ret = -EIO;
61
62 if (drv_attr->show)
63 ret = drv_attr->show(drv_priv->driver, buf);
64 return ret;
65}
66
67static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr,
68 const char *buf, size_t count)
69{
70 struct driver_attribute *drv_attr = to_drv_attr(attr);
71 struct driver_private *drv_priv = to_driver(kobj);
72 ssize_t ret = -EIO;
73
74 if (drv_attr->store)
75 ret = drv_attr->store(drv_priv->driver, buf, count);
76 return ret;
77}
78
79static const struct sysfs_ops driver_sysfs_ops = {
80 .show = drv_attr_show,
81 .store = drv_attr_store,
82};
83
84static void driver_release(struct kobject *kobj)
85{
86 struct driver_private *drv_priv = to_driver(kobj);
87
88 pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__);
89 kfree(drv_priv);
90}
91
92static struct kobj_type driver_ktype = {
93 .sysfs_ops = &driver_sysfs_ops,
94 .release = driver_release,
95};
96
97
98
99
100static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr,
101 char *buf)
102{
103 struct bus_attribute *bus_attr = to_bus_attr(attr);
104 struct subsys_private *subsys_priv = to_subsys_private(kobj);
105 ssize_t ret = 0;
106
107 if (bus_attr->show)
108 ret = bus_attr->show(subsys_priv->bus, buf);
109 return ret;
110}
111
112static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr,
113 const char *buf, size_t count)
114{
115 struct bus_attribute *bus_attr = to_bus_attr(attr);
116 struct subsys_private *subsys_priv = to_subsys_private(kobj);
117 ssize_t ret = 0;
118
119 if (bus_attr->store)
120 ret = bus_attr->store(subsys_priv->bus, buf, count);
121 return ret;
122}
123
124static const struct sysfs_ops bus_sysfs_ops = {
125 .show = bus_attr_show,
126 .store = bus_attr_store,
127};
128
129int bus_create_file(struct bus_type *bus, struct bus_attribute *attr)
130{
131 int error;
132 if (bus_get(bus)) {
133 error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr);
134 bus_put(bus);
135 } else
136 error = -EINVAL;
137 return error;
138}
139EXPORT_SYMBOL_GPL(bus_create_file);
140
141void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr)
142{
143 if (bus_get(bus)) {
144 sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr);
145 bus_put(bus);
146 }
147}
148EXPORT_SYMBOL_GPL(bus_remove_file);
149
150static void bus_release(struct kobject *kobj)
151{
152 struct subsys_private *priv = to_subsys_private(kobj);
153 struct bus_type *bus = priv->bus;
154
155 kfree(priv);
156 bus->p = NULL;
157}
158
159static struct kobj_type bus_ktype = {
160 .sysfs_ops = &bus_sysfs_ops,
161 .release = bus_release,
162};
163
164static int bus_uevent_filter(struct kset *kset, struct kobject *kobj)
165{
166 struct kobj_type *ktype = get_ktype(kobj);
167
168 if (ktype == &bus_ktype)
169 return 1;
170 return 0;
171}
172
173static const struct kset_uevent_ops bus_uevent_ops = {
174 .filter = bus_uevent_filter,
175};
176
177static struct kset *bus_kset;
178
179
180static ssize_t unbind_store(struct device_driver *drv, const char *buf,
181 size_t count)
182{
183 struct bus_type *bus = bus_get(drv->bus);
184 struct device *dev;
185 int err = -ENODEV;
186
187 dev = bus_find_device_by_name(bus, NULL, buf);
188 if (dev && dev->driver == drv) {
189 if (dev->parent)
190 device_lock(dev->parent);
191 device_release_driver(dev);
192 if (dev->parent)
193 device_unlock(dev->parent);
194 err = count;
195 }
196 put_device(dev);
197 bus_put(bus);
198 return err;
199}
200static DRIVER_ATTR_WO(unbind);
201
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206
207static ssize_t bind_store(struct device_driver *drv, const char *buf,
208 size_t count)
209{
210 struct bus_type *bus = bus_get(drv->bus);
211 struct device *dev;
212 int err = -ENODEV;
213
214 dev = bus_find_device_by_name(bus, NULL, buf);
215 if (dev && dev->driver == NULL && driver_match_device(drv, dev)) {
216 if (dev->parent)
217 device_lock(dev->parent);
218 device_lock(dev);
219 err = driver_probe_device(drv, dev);
220 device_unlock(dev);
221 if (dev->parent)
222 device_unlock(dev->parent);
223
224 if (err > 0) {
225
226 err = count;
227 } else if (err == 0) {
228
229 err = -ENODEV;
230 }
231 }
232 put_device(dev);
233 bus_put(bus);
234 return err;
235}
236static DRIVER_ATTR_WO(bind);
237
238static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf)
239{
240 return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);
241}
242
243static ssize_t store_drivers_autoprobe(struct bus_type *bus,
244 const char *buf, size_t count)
245{
246 if (buf[0] == '0')
247 bus->p->drivers_autoprobe = 0;
248 else
249 bus->p->drivers_autoprobe = 1;
250 return count;
251}
252
253static ssize_t store_drivers_probe(struct bus_type *bus,
254 const char *buf, size_t count)
255{
256 struct device *dev;
257 int err = -EINVAL;
258
259 dev = bus_find_device_by_name(bus, NULL, buf);
260 if (!dev)
261 return -ENODEV;
262 if (bus_rescan_devices_helper(dev, NULL) == 0)
263 err = count;
264 put_device(dev);
265 return err;
266}
267
268static struct device *next_device(struct klist_iter *i)
269{
270 struct klist_node *n = klist_next(i);
271 struct device *dev = NULL;
272 struct device_private *dev_prv;
273
274 if (n) {
275 dev_prv = to_device_private_bus(n);
276 dev = dev_prv->device;
277 }
278 return dev;
279}
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300int bus_for_each_dev(struct bus_type *bus, struct device *start,
301 void *data, int (*fn)(struct device *, void *))
302{
303 struct klist_iter i;
304 struct device *dev;
305 int error = 0;
306
307 if (!bus || !bus->p)
308 return -EINVAL;
309
310 klist_iter_init_node(&bus->p->klist_devices, &i,
311 (start ? &start->p->knode_bus : NULL));
312 while ((dev = next_device(&i)) && !error)
313 error = fn(dev, data);
314 klist_iter_exit(&i);
315 return error;
316}
317EXPORT_SYMBOL_GPL(bus_for_each_dev);
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334struct device *bus_find_device(struct bus_type *bus,
335 struct device *start, void *data,
336 int (*match)(struct device *dev, void *data))
337{
338 struct klist_iter i;
339 struct device *dev;
340
341 if (!bus || !bus->p)
342 return NULL;
343
344 klist_iter_init_node(&bus->p->klist_devices, &i,
345 (start ? &start->p->knode_bus : NULL));
346 while ((dev = next_device(&i)))
347 if (match(dev, data) && get_device(dev))
348 break;
349 klist_iter_exit(&i);
350 return dev;
351}
352EXPORT_SYMBOL_GPL(bus_find_device);
353
354static int match_name(struct device *dev, void *data)
355{
356 const char *name = data;
357
358 return sysfs_streq(name, dev_name(dev));
359}
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371struct device *bus_find_device_by_name(struct bus_type *bus,
372 struct device *start, const char *name)
373{
374 return bus_find_device(bus, start, (void *)name, match_name);
375}
376EXPORT_SYMBOL_GPL(bus_find_device_by_name);
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387
388struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id,
389 struct device *hint)
390{
391 struct klist_iter i;
392 struct device *dev;
393
394 if (!subsys)
395 return NULL;
396
397 if (hint) {
398 klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus);
399 dev = next_device(&i);
400 if (dev && dev->id == id && get_device(dev)) {
401 klist_iter_exit(&i);
402 return dev;
403 }
404 klist_iter_exit(&i);
405 }
406
407 klist_iter_init_node(&subsys->p->klist_devices, &i, NULL);
408 while ((dev = next_device(&i))) {
409 if (dev->id == id && get_device(dev)) {
410 klist_iter_exit(&i);
411 return dev;
412 }
413 }
414 klist_iter_exit(&i);
415 return NULL;
416}
417EXPORT_SYMBOL_GPL(subsys_find_device_by_id);
418
419static struct device_driver *next_driver(struct klist_iter *i)
420{
421 struct klist_node *n = klist_next(i);
422 struct driver_private *drv_priv;
423
424 if (n) {
425 drv_priv = container_of(n, struct driver_private, knode_bus);
426 return drv_priv->driver;
427 }
428 return NULL;
429}
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449
450int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
451 void *data, int (*fn)(struct device_driver *, void *))
452{
453 struct klist_iter i;
454 struct device_driver *drv;
455 int error = 0;
456
457 if (!bus)
458 return -EINVAL;
459
460 klist_iter_init_node(&bus->p->klist_drivers, &i,
461 start ? &start->p->knode_bus : NULL);
462 while ((drv = next_driver(&i)) && !error)
463 error = fn(drv, data);
464 klist_iter_exit(&i);
465 return error;
466}
467EXPORT_SYMBOL_GPL(bus_for_each_drv);
468
469static int device_add_attrs(struct bus_type *bus, struct device *dev)
470{
471 int error = 0;
472 int i;
473
474 if (!bus->dev_attrs)
475 return 0;
476
477 for (i = 0; bus->dev_attrs[i].attr.name; i++) {
478 error = device_create_file(dev, &bus->dev_attrs[i]);
479 if (error) {
480 while (--i >= 0)
481 device_remove_file(dev, &bus->dev_attrs[i]);
482 break;
483 }
484 }
485 return error;
486}
487
488static void device_remove_attrs(struct bus_type *bus, struct device *dev)
489{
490 int i;
491
492 if (bus->dev_attrs) {
493 for (i = 0; bus->dev_attrs[i].attr.name; i++)
494 device_remove_file(dev, &bus->dev_attrs[i]);
495 }
496}
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505
506int bus_add_device(struct device *dev)
507{
508 struct bus_type *bus = bus_get(dev->bus);
509 int error = 0;
510
511 if (bus) {
512 pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev));
513 error = device_add_attrs(bus, dev);
514 if (error)
515 goto out_put;
516 error = device_add_groups(dev, bus->dev_groups);
517 if (error)
518 goto out_id;
519 error = sysfs_create_link(&bus->p->devices_kset->kobj,
520 &dev->kobj, dev_name(dev));
521 if (error)
522 goto out_groups;
523 error = sysfs_create_link(&dev->kobj,
524 &dev->bus->p->subsys.kobj, "subsystem");
525 if (error)
526 goto out_subsys;
527 klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
528 }
529 return 0;
530
531out_subsys:
532 sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
533out_groups:
534 device_remove_groups(dev, bus->dev_groups);
535out_id:
536 device_remove_attrs(bus, dev);
537out_put:
538 bus_put(dev->bus);
539 return error;
540}
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548void bus_probe_device(struct device *dev)
549{
550 struct bus_type *bus = dev->bus;
551 struct subsys_interface *sif;
552
553 if (!bus)
554 return;
555
556 if (bus->p->drivers_autoprobe)
557 device_initial_probe(dev);
558
559 mutex_lock(&bus->p->mutex);
560 list_for_each_entry(sif, &bus->p->interfaces, node)
561 if (sif->add_dev)
562 sif->add_dev(dev, sif);
563 mutex_unlock(&bus->p->mutex);
564}
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576void bus_remove_device(struct device *dev)
577{
578 struct bus_type *bus = dev->bus;
579 struct subsys_interface *sif;
580
581 if (!bus)
582 return;
583
584 mutex_lock(&bus->p->mutex);
585 list_for_each_entry(sif, &bus->p->interfaces, node)
586 if (sif->remove_dev)
587 sif->remove_dev(dev, sif);
588 mutex_unlock(&bus->p->mutex);
589
590 sysfs_remove_link(&dev->kobj, "subsystem");
591 sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
592 dev_name(dev));
593 device_remove_attrs(dev->bus, dev);
594 device_remove_groups(dev, dev->bus->dev_groups);
595 if (klist_node_attached(&dev->p->knode_bus))
596 klist_del(&dev->p->knode_bus);
597
598 pr_debug("bus: '%s': remove device %s\n",
599 dev->bus->name, dev_name(dev));
600 device_release_driver(dev);
601 bus_put(dev->bus);
602}
603
604static int __must_check add_bind_files(struct device_driver *drv)
605{
606 int ret;
607
608 ret = driver_create_file(drv, &driver_attr_unbind);
609 if (ret == 0) {
610 ret = driver_create_file(drv, &driver_attr_bind);
611 if (ret)
612 driver_remove_file(drv, &driver_attr_unbind);
613 }
614 return ret;
615}
616
617static void remove_bind_files(struct device_driver *drv)
618{
619 driver_remove_file(drv, &driver_attr_bind);
620 driver_remove_file(drv, &driver_attr_unbind);
621}
622
623static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe);
624static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO,
625 show_drivers_autoprobe, store_drivers_autoprobe);
626
627static int add_probe_files(struct bus_type *bus)
628{
629 int retval;
630
631 retval = bus_create_file(bus, &bus_attr_drivers_probe);
632 if (retval)
633 goto out;
634
635 retval = bus_create_file(bus, &bus_attr_drivers_autoprobe);
636 if (retval)
637 bus_remove_file(bus, &bus_attr_drivers_probe);
638out:
639 return retval;
640}
641
642static void remove_probe_files(struct bus_type *bus)
643{
644 bus_remove_file(bus, &bus_attr_drivers_autoprobe);
645 bus_remove_file(bus, &bus_attr_drivers_probe);
646}
647
648static ssize_t uevent_store(struct device_driver *drv, const char *buf,
649 size_t count)
650{
651 enum kobject_action action;
652
653 if (kobject_action_type(buf, count, &action) == 0)
654 kobject_uevent(&drv->p->kobj, action);
655 return count;
656}
657static DRIVER_ATTR_WO(uevent);
658
659static void driver_attach_async(void *_drv, async_cookie_t cookie)
660{
661 struct device_driver *drv = _drv;
662 int ret;
663
664 ret = driver_attach(drv);
665
666 pr_debug("bus: '%s': driver %s async attach completed: %d\n",
667 drv->bus->name, drv->name, ret);
668}
669
670
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672
673
674int bus_add_driver(struct device_driver *drv)
675{
676 struct bus_type *bus;
677 struct driver_private *priv;
678 int error = 0;
679
680 bus = bus_get(drv->bus);
681 if (!bus)
682 return -EINVAL;
683
684 pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);
685
686 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
687 if (!priv) {
688 error = -ENOMEM;
689 goto out_put_bus;
690 }
691 klist_init(&priv->klist_devices, NULL, NULL);
692 priv->driver = drv;
693 drv->p = priv;
694 priv->kobj.kset = bus->p->drivers_kset;
695 error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,
696 "%s", drv->name);
697 if (error)
698 goto out_unregister;
699
700 klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);
701 if (drv->bus->p->drivers_autoprobe) {
702 if (driver_allows_async_probing(drv)) {
703 pr_debug("bus: '%s': probing driver %s asynchronously\n",
704 drv->bus->name, drv->name);
705 async_schedule(driver_attach_async, drv);
706 } else {
707 error = driver_attach(drv);
708 if (error)
709 goto out_unregister;
710 }
711 }
712 module_add_driver(drv->owner, drv);
713
714 error = driver_create_file(drv, &driver_attr_uevent);
715 if (error) {
716 printk(KERN_ERR "%s: uevent attr (%s) failed\n",
717 __func__, drv->name);
718 }
719 error = driver_add_groups(drv, bus->drv_groups);
720 if (error) {
721
722 printk(KERN_ERR "%s: driver_create_groups(%s) failed\n",
723 __func__, drv->name);
724 }
725
726 if (!drv->suppress_bind_attrs) {
727 error = add_bind_files(drv);
728 if (error) {
729
730 printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
731 __func__, drv->name);
732 }
733 }
734
735 return 0;
736
737out_unregister:
738 kobject_put(&priv->kobj);
739 kfree(drv->p);
740 drv->p = NULL;
741out_put_bus:
742 bus_put(bus);
743 return error;
744}
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754void bus_remove_driver(struct device_driver *drv)
755{
756 if (!drv->bus)
757 return;
758
759 if (!drv->suppress_bind_attrs)
760 remove_bind_files(drv);
761 driver_remove_groups(drv, drv->bus->drv_groups);
762 driver_remove_file(drv, &driver_attr_uevent);
763 klist_remove(&drv->p->knode_bus);
764 pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name);
765 driver_detach(drv);
766 module_remove_driver(drv);
767 kobject_put(&drv->p->kobj);
768 bus_put(drv->bus);
769}
770
771
772static int __must_check bus_rescan_devices_helper(struct device *dev,
773 void *data)
774{
775 int ret = 0;
776
777 if (!dev->driver) {
778 if (dev->parent)
779 device_lock(dev->parent);
780 ret = device_attach(dev);
781 if (dev->parent)
782 device_unlock(dev->parent);
783 }
784 return ret < 0 ? ret : 0;
785}
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795int bus_rescan_devices(struct bus_type *bus)
796{
797 return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper);
798}
799EXPORT_SYMBOL_GPL(bus_rescan_devices);
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810int device_reprobe(struct device *dev)
811{
812 if (dev->driver) {
813 if (dev->parent)
814 device_lock(dev->parent);
815 device_release_driver(dev);
816 if (dev->parent)
817 device_unlock(dev->parent);
818 }
819 return bus_rescan_devices_helper(dev, NULL);
820}
821EXPORT_SYMBOL_GPL(device_reprobe);
822
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831
832#if 0
833struct bus_type *find_bus(char *name)
834{
835 struct kobject *k = kset_find_obj(bus_kset, name);
836 return k ? to_bus(k) : NULL;
837}
838#endif
839
840static int bus_add_groups(struct bus_type *bus,
841 const struct attribute_group **groups)
842{
843 return sysfs_create_groups(&bus->p->subsys.kobj, groups);
844}
845
846static void bus_remove_groups(struct bus_type *bus,
847 const struct attribute_group **groups)
848{
849 sysfs_remove_groups(&bus->p->subsys.kobj, groups);
850}
851
852static void klist_devices_get(struct klist_node *n)
853{
854 struct device_private *dev_prv = to_device_private_bus(n);
855 struct device *dev = dev_prv->device;
856
857 get_device(dev);
858}
859
860static void klist_devices_put(struct klist_node *n)
861{
862 struct device_private *dev_prv = to_device_private_bus(n);
863 struct device *dev = dev_prv->device;
864
865 put_device(dev);
866}
867
868static ssize_t bus_uevent_store(struct bus_type *bus,
869 const char *buf, size_t count)
870{
871 enum kobject_action action;
872
873 if (kobject_action_type(buf, count, &action) == 0)
874 kobject_uevent(&bus->p->subsys.kobj, action);
875 return count;
876}
877static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store);
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885
886
887int bus_register(struct bus_type *bus)
888{
889 int retval;
890 struct subsys_private *priv;
891 struct lock_class_key *key = &bus->lock_key;
892
893 priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL);
894 if (!priv)
895 return -ENOMEM;
896
897 priv->bus = bus;
898 bus->p = priv;
899
900 BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);
901
902 retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name);
903 if (retval)
904 goto out;
905
906 priv->subsys.kobj.kset = bus_kset;
907 priv->subsys.kobj.ktype = &bus_ktype;
908 priv->drivers_autoprobe = 1;
909
910 retval = kset_register(&priv->subsys);
911 if (retval)
912 goto out;
913
914 retval = bus_create_file(bus, &bus_attr_uevent);
915 if (retval)
916 goto bus_uevent_fail;
917
918 priv->devices_kset = kset_create_and_add("devices", NULL,
919 &priv->subsys.kobj);
920 if (!priv->devices_kset) {
921 retval = -ENOMEM;
922 goto bus_devices_fail;
923 }
924
925 priv->drivers_kset = kset_create_and_add("drivers", NULL,
926 &priv->subsys.kobj);
927 if (!priv->drivers_kset) {
928 retval = -ENOMEM;
929 goto bus_drivers_fail;
930 }
931
932 INIT_LIST_HEAD(&priv->interfaces);
933 __mutex_init(&priv->mutex, "subsys mutex", key);
934 klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put);
935 klist_init(&priv->klist_drivers, NULL, NULL);
936
937 retval = add_probe_files(bus);
938 if (retval)
939 goto bus_probe_files_fail;
940
941 retval = bus_add_groups(bus, bus->bus_groups);
942 if (retval)
943 goto bus_groups_fail;
944
945 pr_debug("bus: '%s': registered\n", bus->name);
946 return 0;
947
948bus_groups_fail:
949 remove_probe_files(bus);
950bus_probe_files_fail:
951 kset_unregister(bus->p->drivers_kset);
952bus_drivers_fail:
953 kset_unregister(bus->p->devices_kset);
954bus_devices_fail:
955 bus_remove_file(bus, &bus_attr_uevent);
956bus_uevent_fail:
957 kset_unregister(&bus->p->subsys);
958out:
959 kfree(bus->p);
960 bus->p = NULL;
961 return retval;
962}
963EXPORT_SYMBOL_GPL(bus_register);
964
965
966
967
968
969
970
971
972void bus_unregister(struct bus_type *bus)
973{
974 pr_debug("bus: '%s': unregistering\n", bus->name);
975 if (bus->dev_root)
976 device_unregister(bus->dev_root);
977 bus_remove_groups(bus, bus->bus_groups);
978 remove_probe_files(bus);
979 kset_unregister(bus->p->drivers_kset);
980 kset_unregister(bus->p->devices_kset);
981 bus_remove_file(bus, &bus_attr_uevent);
982 kset_unregister(&bus->p->subsys);
983}
984EXPORT_SYMBOL_GPL(bus_unregister);
985
986int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb)
987{
988 return blocking_notifier_chain_register(&bus->p->bus_notifier, nb);
989}
990EXPORT_SYMBOL_GPL(bus_register_notifier);
991
992int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb)
993{
994 return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb);
995}
996EXPORT_SYMBOL_GPL(bus_unregister_notifier);
997
998struct kset *bus_get_kset(struct bus_type *bus)
999{
1000 return &bus->p->subsys;
1001}
1002EXPORT_SYMBOL_GPL(bus_get_kset);
1003
1004struct klist *bus_get_device_klist(struct bus_type *bus)
1005{
1006 return &bus->p->klist_devices;
1007}
1008EXPORT_SYMBOL_GPL(bus_get_device_klist);
1009
1010
1011
1012
1013
1014
1015
1016
1017static void device_insertion_sort_klist(struct device *a, struct list_head *list,
1018 int (*compare)(const struct device *a,
1019 const struct device *b))
1020{
1021 struct klist_node *n;
1022 struct device_private *dev_prv;
1023 struct device *b;
1024
1025 list_for_each_entry(n, list, n_node) {
1026 dev_prv = to_device_private_bus(n);
1027 b = dev_prv->device;
1028 if (compare(a, b) <= 0) {
1029 list_move_tail(&a->p->knode_bus.n_node,
1030 &b->p->knode_bus.n_node);
1031 return;
1032 }
1033 }
1034 list_move_tail(&a->p->knode_bus.n_node, list);
1035}
1036
1037void bus_sort_breadthfirst(struct bus_type *bus,
1038 int (*compare)(const struct device *a,
1039 const struct device *b))
1040{
1041 LIST_HEAD(sorted_devices);
1042 struct klist_node *n, *tmp;
1043 struct device_private *dev_prv;
1044 struct device *dev;
1045 struct klist *device_klist;
1046
1047 device_klist = bus_get_device_klist(bus);
1048
1049 spin_lock(&device_klist->k_lock);
1050 list_for_each_entry_safe(n, tmp, &device_klist->k_list, n_node) {
1051 dev_prv = to_device_private_bus(n);
1052 dev = dev_prv->device;
1053 device_insertion_sort_klist(dev, &sorted_devices, compare);
1054 }
1055 list_splice(&sorted_devices, &device_klist->k_list);
1056 spin_unlock(&device_klist->k_lock);
1057}
1058EXPORT_SYMBOL_GPL(bus_sort_breadthfirst);
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys,
1073 struct device *start, const struct device_type *type)
1074{
1075 struct klist_node *start_knode = NULL;
1076
1077 if (start)
1078 start_knode = &start->p->knode_bus;
1079 klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode);
1080 iter->type = type;
1081}
1082EXPORT_SYMBOL_GPL(subsys_dev_iter_init);
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter)
1097{
1098 struct klist_node *knode;
1099 struct device *dev;
1100
1101 for (;;) {
1102 knode = klist_next(&iter->ki);
1103 if (!knode)
1104 return NULL;
1105 dev = to_device_private_bus(knode)->device;
1106 if (!iter->type || iter->type == dev->type)
1107 return dev;
1108 }
1109}
1110EXPORT_SYMBOL_GPL(subsys_dev_iter_next);
1111
1112
1113
1114
1115
1116
1117
1118
1119void subsys_dev_iter_exit(struct subsys_dev_iter *iter)
1120{
1121 klist_iter_exit(&iter->ki);
1122}
1123EXPORT_SYMBOL_GPL(subsys_dev_iter_exit);
1124
1125int subsys_interface_register(struct subsys_interface *sif)
1126{
1127 struct bus_type *subsys;
1128 struct subsys_dev_iter iter;
1129 struct device *dev;
1130
1131 if (!sif || !sif->subsys)
1132 return -ENODEV;
1133
1134 subsys = bus_get(sif->subsys);
1135 if (!subsys)
1136 return -EINVAL;
1137
1138 mutex_lock(&subsys->p->mutex);
1139 list_add_tail(&sif->node, &subsys->p->interfaces);
1140 if (sif->add_dev) {
1141 subsys_dev_iter_init(&iter, subsys, NULL, NULL);
1142 while ((dev = subsys_dev_iter_next(&iter)))
1143 sif->add_dev(dev, sif);
1144 subsys_dev_iter_exit(&iter);
1145 }
1146 mutex_unlock(&subsys->p->mutex);
1147
1148 return 0;
1149}
1150EXPORT_SYMBOL_GPL(subsys_interface_register);
1151
1152void subsys_interface_unregister(struct subsys_interface *sif)
1153{
1154 struct bus_type *subsys;
1155 struct subsys_dev_iter iter;
1156 struct device *dev;
1157
1158 if (!sif || !sif->subsys)
1159 return;
1160
1161 subsys = sif->subsys;
1162
1163 mutex_lock(&subsys->p->mutex);
1164 list_del_init(&sif->node);
1165 if (sif->remove_dev) {
1166 subsys_dev_iter_init(&iter, subsys, NULL, NULL);
1167 while ((dev = subsys_dev_iter_next(&iter)))
1168 sif->remove_dev(dev, sif);
1169 subsys_dev_iter_exit(&iter);
1170 }
1171 mutex_unlock(&subsys->p->mutex);
1172
1173 bus_put(subsys);
1174}
1175EXPORT_SYMBOL_GPL(subsys_interface_unregister);
1176
1177static void system_root_device_release(struct device *dev)
1178{
1179 kfree(dev);
1180}
1181
1182static int subsys_register(struct bus_type *subsys,
1183 const struct attribute_group **groups,
1184 struct kobject *parent_of_root)
1185{
1186 struct device *dev;
1187 int err;
1188
1189 err = bus_register(subsys);
1190 if (err < 0)
1191 return err;
1192
1193 dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1194 if (!dev) {
1195 err = -ENOMEM;
1196 goto err_dev;
1197 }
1198
1199 err = dev_set_name(dev, "%s", subsys->name);
1200 if (err < 0)
1201 goto err_name;
1202
1203 dev->kobj.parent = parent_of_root;
1204 dev->groups = groups;
1205 dev->release = system_root_device_release;
1206
1207 err = device_register(dev);
1208 if (err < 0)
1209 goto err_dev_reg;
1210
1211 subsys->dev_root = dev;
1212 return 0;
1213
1214err_dev_reg:
1215 put_device(dev);
1216 dev = NULL;
1217err_name:
1218 kfree(dev);
1219err_dev:
1220 bus_unregister(subsys);
1221 return err;
1222}
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242int subsys_system_register(struct bus_type *subsys,
1243 const struct attribute_group **groups)
1244{
1245 return subsys_register(subsys, groups, &system_kset->kobj);
1246}
1247EXPORT_SYMBOL_GPL(subsys_system_register);
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260int subsys_virtual_register(struct bus_type *subsys,
1261 const struct attribute_group **groups)
1262{
1263 struct kobject *virtual_dir;
1264
1265 virtual_dir = virtual_device_parent(NULL);
1266 if (!virtual_dir)
1267 return -ENOMEM;
1268
1269 return subsys_register(subsys, groups, virtual_dir);
1270}
1271EXPORT_SYMBOL_GPL(subsys_virtual_register);
1272
1273int __init buses_init(void)
1274{
1275 bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL);
1276 if (!bus_kset)
1277 return -ENOMEM;
1278
1279 system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj);
1280 if (!system_kset)
1281 return -ENOMEM;
1282
1283 return 0;
1284}
1285