Commit | Line | Data |
---|---|---|
989d42e8 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * bus.c - bus driver management | |
4 | * | |
5 | * Copyright (c) 2002-3 Patrick Mochel | |
6 | * Copyright (c) 2002-3 Open Source Development Labs | |
e5dd1278 GKH |
7 | * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de> |
8 | * Copyright (c) 2007 Novell Inc. | |
1da177e4 LT |
9 | */ |
10 | ||
765230b5 | 11 | #include <linux/async.h> |
5aee2bf2 | 12 | #include <linux/device/bus.h> |
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 | 34 | |
4f4b3743 DV |
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) | |
1da177e4 | 38 | |
b8c5cec2 KS |
39 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
40 | void *data); | |
41 | ||
5901d014 GKH |
42 | static struct bus_type *bus_get(struct bus_type *bus) |
43 | { | |
c6f7e72a GKH |
44 | if (bus) { |
45 | kset_get(&bus->p->subsys); | |
46 | return bus; | |
47 | } | |
48 | return NULL; | |
5901d014 GKH |
49 | } |
50 | ||
fc1ede58 GKH |
51 | static void bus_put(struct bus_type *bus) |
52 | { | |
c6f7e72a GKH |
53 | if (bus) |
54 | kset_put(&bus->p->subsys); | |
fc1ede58 GKH |
55 | } |
56 | ||
4a3ad20c GKH |
57 | static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr, |
58 | char *buf) | |
1da177e4 | 59 | { |
4a3ad20c | 60 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 61 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 62 | ssize_t ret = -EIO; |
1da177e4 LT |
63 | |
64 | if (drv_attr->show) | |
e5dd1278 | 65 | ret = drv_attr->show(drv_priv->driver, buf); |
1da177e4 LT |
66 | return ret; |
67 | } | |
68 | ||
4a3ad20c GKH |
69 | static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr, |
70 | const char *buf, size_t count) | |
1da177e4 | 71 | { |
4a3ad20c | 72 | struct driver_attribute *drv_attr = to_drv_attr(attr); |
e5dd1278 | 73 | struct driver_private *drv_priv = to_driver(kobj); |
4a0c20bf | 74 | ssize_t ret = -EIO; |
1da177e4 LT |
75 | |
76 | if (drv_attr->store) | |
e5dd1278 | 77 | ret = drv_attr->store(drv_priv->driver, buf, count); |
1da177e4 LT |
78 | return ret; |
79 | } | |
80 | ||
52cf25d0 | 81 | static const struct sysfs_ops driver_sysfs_ops = { |
1da177e4 LT |
82 | .show = drv_attr_show, |
83 | .store = drv_attr_store, | |
84 | }; | |
85 | ||
e5dd1278 | 86 | static void driver_release(struct kobject *kobj) |
1da177e4 | 87 | { |
e5dd1278 GKH |
88 | struct driver_private *drv_priv = to_driver(kobj); |
89 | ||
2b3a302a | 90 | pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__); |
e5dd1278 | 91 | kfree(drv_priv); |
1da177e4 LT |
92 | } |
93 | ||
a1148fb0 | 94 | static struct kobj_type driver_ktype = { |
1da177e4 LT |
95 | .sysfs_ops = &driver_sysfs_ops, |
96 | .release = driver_release, | |
97 | }; | |
98 | ||
1da177e4 LT |
99 | /* |
100 | * sysfs bindings for buses | |
101 | */ | |
4a3ad20c GKH |
102 | static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr, |
103 | char *buf) | |
1da177e4 | 104 | { |
4a3ad20c | 105 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 106 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
107 | ssize_t ret = 0; |
108 | ||
109 | if (bus_attr->show) | |
6b6e39a6 | 110 | ret = bus_attr->show(subsys_priv->bus, buf); |
1da177e4 LT |
111 | return ret; |
112 | } | |
113 | ||
4a3ad20c GKH |
114 | static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr, |
115 | const char *buf, size_t count) | |
1da177e4 | 116 | { |
4a3ad20c | 117 | struct bus_attribute *bus_attr = to_bus_attr(attr); |
6b6e39a6 | 118 | struct subsys_private *subsys_priv = to_subsys_private(kobj); |
1da177e4 LT |
119 | ssize_t ret = 0; |
120 | ||
121 | if (bus_attr->store) | |
6b6e39a6 | 122 | ret = bus_attr->store(subsys_priv->bus, buf, count); |
1da177e4 LT |
123 | return ret; |
124 | } | |
125 | ||
52cf25d0 | 126 | static const struct sysfs_ops bus_sysfs_ops = { |
1da177e4 LT |
127 | .show = bus_attr_show, |
128 | .store = bus_attr_store, | |
129 | }; | |
130 | ||
4a3ad20c | 131 | int bus_create_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 LT |
132 | { |
133 | int error; | |
5901d014 | 134 | if (bus_get(bus)) { |
c6f7e72a | 135 | error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 136 | bus_put(bus); |
1da177e4 LT |
137 | } else |
138 | error = -EINVAL; | |
139 | return error; | |
140 | } | |
4a3ad20c | 141 | EXPORT_SYMBOL_GPL(bus_create_file); |
1da177e4 | 142 | |
4a3ad20c | 143 | void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr) |
1da177e4 | 144 | { |
5901d014 | 145 | if (bus_get(bus)) { |
c6f7e72a | 146 | sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr); |
fc1ede58 | 147 | bus_put(bus); |
1da177e4 LT |
148 | } |
149 | } | |
4a3ad20c | 150 | EXPORT_SYMBOL_GPL(bus_remove_file); |
1da177e4 | 151 | |
174be70b BVA |
152 | static void bus_release(struct kobject *kobj) |
153 | { | |
371fd7a2 | 154 | struct subsys_private *priv = to_subsys_private(kobj); |
174be70b BVA |
155 | struct bus_type *bus = priv->bus; |
156 | ||
157 | kfree(priv); | |
158 | bus->p = NULL; | |
159 | } | |
160 | ||
80f03e34 | 161 | static struct kobj_type bus_ktype = { |
1da177e4 | 162 | .sysfs_ops = &bus_sysfs_ops, |
174be70b | 163 | .release = bus_release, |
80f03e34 KS |
164 | }; |
165 | ||
c45a88bb | 166 | static int bus_uevent_filter(const struct kobject *kobj) |
80f03e34 | 167 | { |
ee6d3dd4 | 168 | const struct kobj_type *ktype = get_ktype(kobj); |
80f03e34 KS |
169 | |
170 | if (ktype == &bus_ktype) | |
171 | return 1; | |
172 | return 0; | |
173 | } | |
1da177e4 | 174 | |
9cd43611 | 175 | static const struct kset_uevent_ops bus_uevent_ops = { |
80f03e34 | 176 | .filter = bus_uevent_filter, |
1da177e4 LT |
177 | }; |
178 | ||
59a54833 | 179 | static struct kset *bus_kset; |
1da177e4 | 180 | |
2b08c8d0 | 181 | /* Manually detach a device from its associated driver. */ |
2581c9cc GKH |
182 | static ssize_t unbind_store(struct device_driver *drv, const char *buf, |
183 | size_t count) | |
151ef38f | 184 | { |
5901d014 | 185 | struct bus_type *bus = bus_get(drv->bus); |
151ef38f GKH |
186 | struct device *dev; |
187 | int err = -ENODEV; | |
188 | ||
1f9ffc04 | 189 | dev = bus_find_device_by_name(bus, NULL, buf); |
2b08c8d0 | 190 | if (dev && dev->driver == drv) { |
ed88747c | 191 | device_driver_detach(dev); |
151ef38f GKH |
192 | err = count; |
193 | } | |
2b08c8d0 | 194 | put_device(dev); |
fc1ede58 | 195 | bus_put(bus); |
2b08c8d0 | 196 | return err; |
151ef38f | 197 | } |
16b0dd40 | 198 | static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store); |
151ef38f | 199 | |
afdce75f GKH |
200 | /* |
201 | * Manually attach a device to a driver. | |
202 | * Note: the driver must want to bind to the device, | |
203 | * it is not possible to override the driver's id table. | |
204 | */ | |
2581c9cc GKH |
205 | static ssize_t bind_store(struct device_driver *drv, const char *buf, |
206 | size_t count) | |
afdce75f | 207 | { |
5901d014 | 208 | struct bus_type *bus = bus_get(drv->bus); |
afdce75f GKH |
209 | struct device *dev; |
210 | int err = -ENODEV; | |
211 | ||
1f9ffc04 | 212 | dev = bus_find_device_by_name(bus, NULL, buf); |
204db60c | 213 | if (dev && driver_match_device(drv, dev)) { |
ed88747c | 214 | err = device_driver_attach(drv, dev); |
ef6dcbdd | 215 | if (!err) { |
4a3ad20c | 216 | /* success */ |
37225401 | 217 | err = count; |
4a3ad20c | 218 | } |
afdce75f | 219 | } |
2b08c8d0 | 220 | put_device(dev); |
fc1ede58 | 221 | bus_put(bus); |
2b08c8d0 | 222 | return err; |
afdce75f | 223 | } |
16b0dd40 | 224 | static DRIVER_ATTR_IGNORE_LOCKDEP(bind, 0200, NULL, bind_store); |
afdce75f | 225 | |
2e7189b6 | 226 | static ssize_t drivers_autoprobe_show(struct bus_type *bus, char *buf) |
b8c5cec2 | 227 | { |
948b3edb | 228 | return sysfs_emit(buf, "%d\n", bus->p->drivers_autoprobe); |
b8c5cec2 KS |
229 | } |
230 | ||
2e7189b6 | 231 | static ssize_t drivers_autoprobe_store(struct bus_type *bus, |
b8c5cec2 KS |
232 | const char *buf, size_t count) |
233 | { | |
234 | if (buf[0] == '0') | |
c6f7e72a | 235 | bus->p->drivers_autoprobe = 0; |
b8c5cec2 | 236 | else |
c6f7e72a | 237 | bus->p->drivers_autoprobe = 1; |
b8c5cec2 KS |
238 | return count; |
239 | } | |
240 | ||
2e7189b6 | 241 | static ssize_t drivers_probe_store(struct bus_type *bus, |
b8c5cec2 KS |
242 | const char *buf, size_t count) |
243 | { | |
244 | struct device *dev; | |
0372ffb3 | 245 | int err = -EINVAL; |
b8c5cec2 | 246 | |
1f9ffc04 | 247 | dev = bus_find_device_by_name(bus, NULL, buf); |
b8c5cec2 KS |
248 | if (!dev) |
249 | return -ENODEV; | |
0372ffb3 AW |
250 | if (bus_rescan_devices_helper(dev, NULL) == 0) |
251 | err = count; | |
252 | put_device(dev); | |
253 | return err; | |
b8c5cec2 | 254 | } |
151ef38f | 255 | |
4a3ad20c | 256 | static struct device *next_device(struct klist_iter *i) |
465c7a3a | 257 | { |
4a3ad20c | 258 | struct klist_node *n = klist_next(i); |
ae1b4171 GKH |
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; | |
465c7a3a | 267 | } |
268 | ||
1da177e4 | 269 | /** |
4a3ad20c GKH |
270 | * bus_for_each_dev - device iterator. |
271 | * @bus: bus type. | |
272 | * @start: device to start iterating from. | |
273 | * @data: data for the callback. | |
274 | * @fn: function to be called for each device. | |
1da177e4 | 275 | * |
4a3ad20c GKH |
276 | * Iterate over @bus's list of devices, and call @fn for each, |
277 | * passing it @data. If @start is not NULL, we use that device to | |
278 | * begin iterating from. | |
1da177e4 | 279 | * |
4a3ad20c GKH |
280 | * We check the return of @fn each time. If it returns anything |
281 | * other than 0, we break out and return that value. | |
1da177e4 | 282 | * |
4a3ad20c GKH |
283 | * NOTE: The device that returns a non-zero value is not retained |
284 | * in any way, nor is its refcount incremented. If the caller needs | |
0fa1b0a1 | 285 | * to retain this data, it should do so, and increment the reference |
4a3ad20c | 286 | * count in the supplied callback. |
1da177e4 | 287 | */ |
4a3ad20c GKH |
288 | int bus_for_each_dev(struct bus_type *bus, struct device *start, |
289 | void *data, int (*fn)(struct device *, void *)) | |
1da177e4 | 290 | { |
465c7a3a | 291 | struct klist_iter i; |
4a3ad20c | 292 | struct device *dev; |
465c7a3a | 293 | int error = 0; |
1da177e4 | 294 | |
4fa3e78b | 295 | if (!bus || !bus->p) |
465c7a3a | 296 | return -EINVAL; |
297 | ||
7cd9c9bb GKH |
298 | klist_iter_init_node(&bus->p->klist_devices, &i, |
299 | (start ? &start->p->knode_bus : NULL)); | |
93ead7c9 | 300 | while (!error && (dev = next_device(&i))) |
7cd9c9bb GKH |
301 | error = fn(dev, data); |
302 | klist_iter_exit(&i); | |
465c7a3a | 303 | return error; |
1da177e4 | 304 | } |
4a3ad20c | 305 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
1da177e4 | 306 | |
0edb5860 CH |
307 | /** |
308 | * bus_find_device - device iterator for locating a particular device. | |
309 | * @bus: bus type | |
310 | * @start: Device to begin with | |
311 | * @data: Data to pass to match function | |
312 | * @match: Callback function to check device | |
313 | * | |
314 | * This is similar to the bus_for_each_dev() function above, but it | |
315 | * returns a reference to a device that is 'found' for later use, as | |
316 | * determined by the @match callback. | |
317 | * | |
318 | * The callback should return 0 if the device doesn't match and non-zero | |
319 | * if it does. If the callback returns non-zero, this function will | |
320 | * return to the caller and not iterate over any more devices. | |
321 | */ | |
4a3ad20c | 322 | struct device *bus_find_device(struct bus_type *bus, |
418e3ea1 SP |
323 | struct device *start, const void *data, |
324 | int (*match)(struct device *dev, const void *data)) | |
0edb5860 CH |
325 | { |
326 | struct klist_iter i; | |
327 | struct device *dev; | |
328 | ||
4fa3e78b | 329 | if (!bus || !bus->p) |
0edb5860 CH |
330 | return NULL; |
331 | ||
7cd9c9bb GKH |
332 | klist_iter_init_node(&bus->p->klist_devices, &i, |
333 | (start ? &start->p->knode_bus : NULL)); | |
0edb5860 CH |
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 | } | |
4a3ad20c | 340 | EXPORT_SYMBOL_GPL(bus_find_device); |
38fdac3c | 341 | |
4a3ad20c | 342 | static struct device_driver *next_driver(struct klist_iter *i) |
38fdac3c | 343 | { |
4a3ad20c | 344 | struct klist_node *n = klist_next(i); |
e5dd1278 GKH |
345 | struct driver_private *drv_priv; |
346 | ||
347 | if (n) { | |
348 | drv_priv = container_of(n, struct driver_private, knode_bus); | |
349 | return drv_priv->driver; | |
350 | } | |
351 | return NULL; | |
38fdac3c | 352 | } |
353 | ||
1da177e4 | 354 | /** |
4a3ad20c GKH |
355 | * bus_for_each_drv - driver iterator |
356 | * @bus: bus we're dealing with. | |
357 | * @start: driver to start iterating on. | |
358 | * @data: data to pass to the callback. | |
359 | * @fn: function to call for each driver. | |
1da177e4 | 360 | * |
4a3ad20c GKH |
361 | * This is nearly identical to the device iterator above. |
362 | * We iterate over each driver that belongs to @bus, and call | |
363 | * @fn for each. If @fn returns anything but 0, we break out | |
364 | * and return it. If @start is not NULL, we use it as the head | |
365 | * of the list. | |
1da177e4 | 366 | * |
4a3ad20c GKH |
367 | * NOTE: we don't return the driver that returns a non-zero |
368 | * value, nor do we leave the reference count incremented for that | |
369 | * driver. If the caller needs to know that info, it must set it | |
370 | * in the callback. It must also be sure to increment the refcount | |
371 | * so it doesn't disappear before returning to the caller. | |
1da177e4 | 372 | */ |
4a3ad20c GKH |
373 | int bus_for_each_drv(struct bus_type *bus, struct device_driver *start, |
374 | void *data, int (*fn)(struct device_driver *, void *)) | |
1da177e4 | 375 | { |
38fdac3c | 376 | struct klist_iter i; |
4a3ad20c | 377 | struct device_driver *drv; |
38fdac3c | 378 | int error = 0; |
1da177e4 | 379 | |
38fdac3c | 380 | if (!bus) |
381 | return -EINVAL; | |
382 | ||
7cd9c9bb GKH |
383 | klist_iter_init_node(&bus->p->klist_drivers, &i, |
384 | start ? &start->p->knode_bus : NULL); | |
385 | while ((drv = next_driver(&i)) && !error) | |
386 | error = fn(drv, data); | |
387 | klist_iter_exit(&i); | |
38fdac3c | 388 | return error; |
1da177e4 | 389 | } |
4a3ad20c | 390 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
1da177e4 | 391 | |
1da177e4 | 392 | /** |
4a3ad20c GKH |
393 | * bus_add_device - add device to bus |
394 | * @dev: device being added | |
1da177e4 | 395 | * |
2023c610 AS |
396 | * - Add device's bus attributes. |
397 | * - Create links to device's bus. | |
4a3ad20c | 398 | * - Add the device to its bus's list of devices. |
1da177e4 | 399 | */ |
4a3ad20c | 400 | int bus_add_device(struct device *dev) |
1da177e4 | 401 | { |
4a3ad20c | 402 | struct bus_type *bus = bus_get(dev->bus); |
1da177e4 LT |
403 | int error = 0; |
404 | ||
405 | if (bus) { | |
1e0b2cf9 | 406 | pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev)); |
fa6fdb33 GKH |
407 | error = device_add_groups(dev, bus->dev_groups); |
408 | if (error) | |
b46c7337 | 409 | goto out_put; |
c6f7e72a | 410 | error = sysfs_create_link(&bus->p->devices_kset->kobj, |
1e0b2cf9 | 411 | &dev->kobj, dev_name(dev)); |
f86db396 | 412 | if (error) |
1c34203a | 413 | goto out_groups; |
f86db396 | 414 | error = sysfs_create_link(&dev->kobj, |
c6f7e72a | 415 | &dev->bus->p->subsys.kobj, "subsystem"); |
f86db396 | 416 | if (error) |
513e7337 | 417 | goto out_subsys; |
2023c610 | 418 | klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices); |
1da177e4 | 419 | } |
513e7337 CH |
420 | return 0; |
421 | ||
513e7337 | 422 | out_subsys: |
1e0b2cf9 | 423 | sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev)); |
fa6fdb33 GKH |
424 | out_groups: |
425 | device_remove_groups(dev, bus->dev_groups); | |
513e7337 | 426 | out_put: |
fc1ede58 | 427 | bus_put(dev->bus); |
1da177e4 LT |
428 | return error; |
429 | } | |
430 | ||
53877d06 | 431 | /** |
2023c610 AS |
432 | * bus_probe_device - probe drivers for a new device |
433 | * @dev: device to probe | |
53877d06 | 434 | * |
2023c610 | 435 | * - Automatically probe for a driver if the bus allows it. |
53877d06 | 436 | */ |
2023c610 | 437 | void bus_probe_device(struct device *dev) |
53877d06 | 438 | { |
f86db396 | 439 | struct bus_type *bus = dev->bus; |
ca22e56d | 440 | struct subsys_interface *sif; |
53877d06 | 441 | |
ca22e56d KS |
442 | if (!bus) |
443 | return; | |
444 | ||
765230b5 DT |
445 | if (bus->p->drivers_autoprobe) |
446 | device_initial_probe(dev); | |
ca22e56d KS |
447 | |
448 | mutex_lock(&bus->p->mutex); | |
449 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
450 | if (sif->add_dev) | |
451 | sif->add_dev(dev, sif); | |
452 | mutex_unlock(&bus->p->mutex); | |
53877d06 KS |
453 | } |
454 | ||
1da177e4 | 455 | /** |
4a3ad20c GKH |
456 | * bus_remove_device - remove device from bus |
457 | * @dev: device to be removed | |
1da177e4 | 458 | * |
ca22e56d KS |
459 | * - Remove device from all interfaces. |
460 | * - Remove symlink from bus' directory. | |
4a3ad20c GKH |
461 | * - Delete device from bus's list. |
462 | * - Detach from its driver. | |
463 | * - Drop reference taken in bus_add_device(). | |
1da177e4 | 464 | */ |
4a3ad20c | 465 | void bus_remove_device(struct device *dev) |
1da177e4 | 466 | { |
ca22e56d KS |
467 | struct bus_type *bus = dev->bus; |
468 | struct subsys_interface *sif; | |
469 | ||
470 | if (!bus) | |
471 | return; | |
472 | ||
473 | mutex_lock(&bus->p->mutex); | |
474 | list_for_each_entry(sif, &bus->p->interfaces, node) | |
475 | if (sif->remove_dev) | |
476 | sif->remove_dev(dev, sif); | |
477 | mutex_unlock(&bus->p->mutex); | |
478 | ||
479 | sysfs_remove_link(&dev->kobj, "subsystem"); | |
480 | sysfs_remove_link(&dev->bus->p->devices_kset->kobj, | |
481 | dev_name(dev)); | |
fa6fdb33 | 482 | device_remove_groups(dev, dev->bus->dev_groups); |
ca22e56d KS |
483 | if (klist_node_attached(&dev->p->knode_bus)) |
484 | klist_del(&dev->p->knode_bus); | |
485 | ||
486 | pr_debug("bus: '%s': remove device %s\n", | |
487 | dev->bus->name, dev_name(dev)); | |
488 | device_release_driver(dev); | |
489 | bus_put(dev->bus); | |
1da177e4 LT |
490 | } |
491 | ||
f86db396 | 492 | static int __must_check add_bind_files(struct device_driver *drv) |
874c6241 | 493 | { |
f86db396 AM |
494 | int ret; |
495 | ||
496 | ret = driver_create_file(drv, &driver_attr_unbind); | |
497 | if (ret == 0) { | |
498 | ret = driver_create_file(drv, &driver_attr_bind); | |
499 | if (ret) | |
500 | driver_remove_file(drv, &driver_attr_unbind); | |
501 | } | |
502 | return ret; | |
874c6241 GKH |
503 | } |
504 | ||
505 | static void remove_bind_files(struct device_driver *drv) | |
506 | { | |
507 | driver_remove_file(drv, &driver_attr_bind); | |
508 | driver_remove_file(drv, &driver_attr_unbind); | |
509 | } | |
b8c5cec2 | 510 | |
2e7189b6 GKH |
511 | static BUS_ATTR_WO(drivers_probe); |
512 | static BUS_ATTR_RW(drivers_autoprobe); | |
8380770c | 513 | |
b8c5cec2 KS |
514 | static int add_probe_files(struct bus_type *bus) |
515 | { | |
516 | int retval; | |
517 | ||
8380770c | 518 | retval = bus_create_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
519 | if (retval) |
520 | goto out; | |
521 | ||
8380770c | 522 | retval = bus_create_file(bus, &bus_attr_drivers_autoprobe); |
b8c5cec2 | 523 | if (retval) |
8380770c | 524 | bus_remove_file(bus, &bus_attr_drivers_probe); |
b8c5cec2 KS |
525 | out: |
526 | return retval; | |
527 | } | |
528 | ||
529 | static void remove_probe_files(struct bus_type *bus) | |
530 | { | |
8380770c KS |
531 | bus_remove_file(bus, &bus_attr_drivers_autoprobe); |
532 | bus_remove_file(bus, &bus_attr_drivers_probe); | |
b8c5cec2 | 533 | } |
1da177e4 | 534 | |
2581c9cc GKH |
535 | static ssize_t uevent_store(struct device_driver *drv, const char *buf, |
536 | size_t count) | |
7ac1cf4a | 537 | { |
df44b479 PR |
538 | int rc; |
539 | ||
540 | rc = kobject_synth_uevent(&drv->p->kobj, buf, count); | |
541 | return rc ? rc : count; | |
7ac1cf4a | 542 | } |
2581c9cc | 543 | static DRIVER_ATTR_WO(uevent); |
7ac1cf4a | 544 | |
1da177e4 | 545 | /** |
4a3ad20c GKH |
546 | * bus_add_driver - Add a driver to the bus. |
547 | * @drv: driver. | |
1da177e4 | 548 | */ |
f86db396 | 549 | int bus_add_driver(struct device_driver *drv) |
1da177e4 | 550 | { |
e5dd1278 GKH |
551 | struct bus_type *bus; |
552 | struct driver_private *priv; | |
1da177e4 LT |
553 | int error = 0; |
554 | ||
e5dd1278 | 555 | bus = bus_get(drv->bus); |
d9fd4d3b | 556 | if (!bus) |
4f6e1945 | 557 | return -EINVAL; |
d9fd4d3b | 558 | |
7dc72b28 | 559 | pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name); |
e5dd1278 GKH |
560 | |
561 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); | |
07634464 CH |
562 | if (!priv) { |
563 | error = -ENOMEM; | |
564 | goto out_put_bus; | |
565 | } | |
e5dd1278 GKH |
566 | klist_init(&priv->klist_devices, NULL, NULL); |
567 | priv->driver = drv; | |
568 | drv->p = priv; | |
c8e90d82 GKH |
569 | priv->kobj.kset = bus->p->drivers_kset; |
570 | error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL, | |
571 | "%s", drv->name); | |
dc0afa83 | 572 | if (error) |
07634464 | 573 | goto out_unregister; |
d9fd4d3b | 574 | |
190888ac | 575 | klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); |
c6f7e72a | 576 | if (drv->bus->p->drivers_autoprobe) { |
ef0ff683 AD |
577 | error = driver_attach(drv); |
578 | if (error) | |
310862e5 | 579 | goto out_del_list; |
b8c5cec2 | 580 | } |
d9fd4d3b JG |
581 | module_add_driver(drv->owner, drv); |
582 | ||
7ac1cf4a KS |
583 | error = driver_create_file(drv, &driver_attr_uevent); |
584 | if (error) { | |
585 | printk(KERN_ERR "%s: uevent attr (%s) failed\n", | |
2b3a302a | 586 | __func__, drv->name); |
7ac1cf4a | 587 | } |
e18945b1 | 588 | error = driver_add_groups(drv, bus->drv_groups); |
d9fd4d3b JG |
589 | if (error) { |
590 | /* How the hell do we get out of this pickle? Give up */ | |
4044b2fc | 591 | printk(KERN_ERR "%s: driver_add_groups(%s) failed\n", |
ed0617b5 | 592 | __func__, drv->name); |
e18945b1 | 593 | } |
1a6f2a75 DT |
594 | |
595 | if (!drv->suppress_bind_attrs) { | |
596 | error = add_bind_files(drv); | |
597 | if (error) { | |
598 | /* Ditto */ | |
599 | printk(KERN_ERR "%s: add_bind_files(%s) failed\n", | |
600 | __func__, drv->name); | |
601 | } | |
1da177e4 | 602 | } |
d9fd4d3b | 603 | |
5c8563d7 | 604 | return 0; |
1a6f2a75 | 605 | |
310862e5 SS |
606 | out_del_list: |
607 | klist_del(&priv->knode_bus); | |
f86db396 | 608 | out_unregister: |
99b28f1b | 609 | kobject_put(&priv->kobj); |
0f9b011d | 610 | /* drv->p is freed in driver_release() */ |
5c8563d7 | 611 | drv->p = NULL; |
f86db396 | 612 | out_put_bus: |
fc1ede58 | 613 | bus_put(bus); |
f86db396 | 614 | return error; |
1da177e4 LT |
615 | } |
616 | ||
1da177e4 | 617 | /** |
4a3ad20c GKH |
618 | * bus_remove_driver - delete driver from bus's knowledge. |
619 | * @drv: driver. | |
1da177e4 | 620 | * |
4a3ad20c GKH |
621 | * Detach the driver from the devices it controls, and remove |
622 | * it from its bus's list of drivers. Finally, we drop the reference | |
623 | * to the bus we took in bus_add_driver(). | |
1da177e4 | 624 | */ |
4a3ad20c | 625 | void bus_remove_driver(struct device_driver *drv) |
1da177e4 | 626 | { |
d9fd4d3b JG |
627 | if (!drv->bus) |
628 | return; | |
629 | ||
1a6f2a75 DT |
630 | if (!drv->suppress_bind_attrs) |
631 | remove_bind_files(drv); | |
ed0617b5 | 632 | driver_remove_groups(drv, drv->bus->drv_groups); |
7ac1cf4a | 633 | driver_remove_file(drv, &driver_attr_uevent); |
e5dd1278 | 634 | klist_remove(&drv->p->knode_bus); |
7dc72b28 | 635 | pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name); |
d9fd4d3b JG |
636 | driver_detach(drv); |
637 | module_remove_driver(drv); | |
c10997f6 | 638 | kobject_put(&drv->p->kobj); |
fc1ede58 | 639 | bus_put(drv->bus); |
1da177e4 LT |
640 | } |
641 | ||
1da177e4 | 642 | /* Helper for bus_rescan_devices's iter */ |
f86db396 | 643 | static int __must_check bus_rescan_devices_helper(struct device *dev, |
4a3ad20c | 644 | void *data) |
1da177e4 | 645 | { |
f86db396 AM |
646 | int ret = 0; |
647 | ||
bf74ad5b | 648 | if (!dev->driver) { |
8c97a46a | 649 | if (dev->parent && dev->bus->need_parent_lock) |
8e9394ce | 650 | device_lock(dev->parent); |
f86db396 | 651 | ret = device_attach(dev); |
8c97a46a | 652 | if (dev->parent && dev->bus->need_parent_lock) |
8e9394ce | 653 | device_unlock(dev->parent); |
bf74ad5b | 654 | } |
f86db396 | 655 | return ret < 0 ? ret : 0; |
1da177e4 LT |
656 | } |
657 | ||
1da177e4 | 658 | /** |
23d3d602 GKH |
659 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
660 | * @bus: the bus to scan. | |
1da177e4 | 661 | * |
23d3d602 GKH |
662 | * This function will look for devices on the bus with no driver |
663 | * attached and rescan it against existing drivers to see if it matches | |
664 | * any by calling device_attach() for the unbound devices. | |
1da177e4 | 665 | */ |
4a3ad20c | 666 | int bus_rescan_devices(struct bus_type *bus) |
1da177e4 | 667 | { |
f86db396 | 668 | return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
1da177e4 | 669 | } |
4a3ad20c | 670 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
1da177e4 | 671 | |
e935d5da ME |
672 | /** |
673 | * device_reprobe - remove driver for a device and probe for a new driver | |
674 | * @dev: the device to reprobe | |
675 | * | |
676 | * This function detaches the attached driver (if any) for the given | |
677 | * device and restarts the driver probing process. It is intended | |
678 | * to use if probing criteria changed during a devices lifetime and | |
679 | * driver attachment should change accordingly. | |
680 | */ | |
f86db396 | 681 | int device_reprobe(struct device *dev) |
e935d5da | 682 | { |
ed88747c AD |
683 | if (dev->driver) |
684 | device_driver_detach(dev); | |
f86db396 | 685 | return bus_rescan_devices_helper(dev, NULL); |
e935d5da ME |
686 | } |
687 | EXPORT_SYMBOL_GPL(device_reprobe); | |
1da177e4 | 688 | |
12478ba0 GKH |
689 | static int bus_add_groups(struct bus_type *bus, |
690 | const struct attribute_group **groups) | |
691 | { | |
3e9b2bae | 692 | return sysfs_create_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
693 | } |
694 | ||
695 | static void bus_remove_groups(struct bus_type *bus, | |
696 | const struct attribute_group **groups) | |
697 | { | |
3e9b2bae | 698 | sysfs_remove_groups(&bus->p->subsys.kobj, groups); |
12478ba0 GKH |
699 | } |
700 | ||
34bb61f9 JB |
701 | static void klist_devices_get(struct klist_node *n) |
702 | { | |
ae1b4171 GKH |
703 | struct device_private *dev_prv = to_device_private_bus(n); |
704 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
705 | |
706 | get_device(dev); | |
707 | } | |
708 | ||
709 | static void klist_devices_put(struct klist_node *n) | |
710 | { | |
ae1b4171 GKH |
711 | struct device_private *dev_prv = to_device_private_bus(n); |
712 | struct device *dev = dev_prv->device; | |
34bb61f9 JB |
713 | |
714 | put_device(dev); | |
715 | } | |
716 | ||
7ac1cf4a KS |
717 | static ssize_t bus_uevent_store(struct bus_type *bus, |
718 | const char *buf, size_t count) | |
719 | { | |
df44b479 PR |
720 | int rc; |
721 | ||
722 | rc = kobject_synth_uevent(&bus->p->subsys.kobj, buf, count); | |
723 | return rc ? rc : count; | |
7ac1cf4a | 724 | } |
a4723041 GKH |
725 | /* |
726 | * "open code" the old BUS_ATTR() macro here. We want to use BUS_ATTR_WO() | |
727 | * here, but can not use it as earlier in the file we have | |
728 | * DEVICE_ATTR_WO(uevent), which would cause a clash with the with the store | |
729 | * function name. | |
730 | */ | |
16b0dd40 | 731 | static struct bus_attribute bus_attr_uevent = __ATTR(uevent, 0200, NULL, |
a4723041 | 732 | bus_uevent_store); |
7ac1cf4a | 733 | |
1da177e4 | 734 | /** |
be871b7e | 735 | * bus_register - register a driver-core subsystem |
78d79559 | 736 | * @bus: bus to register |
1da177e4 | 737 | * |
78d79559 | 738 | * Once we have that, we register the bus with the kobject |
4a3ad20c | 739 | * infrastructure, then register the children subsystems it has: |
ca22e56d | 740 | * the devices and drivers that belong to the subsystem. |
1da177e4 | 741 | */ |
be871b7e | 742 | int bus_register(struct bus_type *bus) |
1da177e4 LT |
743 | { |
744 | int retval; | |
6b6e39a6 | 745 | struct subsys_private *priv; |
be871b7e | 746 | struct lock_class_key *key = &bus->lock_key; |
c6f7e72a | 747 | |
6b6e39a6 | 748 | priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL); |
c6f7e72a GKH |
749 | if (!priv) |
750 | return -ENOMEM; | |
751 | ||
752 | priv->bus = bus; | |
753 | bus->p = priv; | |
1da177e4 | 754 | |
c6f7e72a | 755 | BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier); |
116af378 | 756 | |
c6f7e72a | 757 | retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name); |
1da177e4 LT |
758 | if (retval) |
759 | goto out; | |
760 | ||
c6f7e72a GKH |
761 | priv->subsys.kobj.kset = bus_kset; |
762 | priv->subsys.kobj.ktype = &bus_ktype; | |
763 | priv->drivers_autoprobe = 1; | |
d6b05b84 | 764 | |
c6f7e72a | 765 | retval = kset_register(&priv->subsys); |
1da177e4 LT |
766 | if (retval) |
767 | goto out; | |
768 | ||
7ac1cf4a KS |
769 | retval = bus_create_file(bus, &bus_attr_uevent); |
770 | if (retval) | |
771 | goto bus_uevent_fail; | |
772 | ||
c6f7e72a GKH |
773 | priv->devices_kset = kset_create_and_add("devices", NULL, |
774 | &priv->subsys.kobj); | |
775 | if (!priv->devices_kset) { | |
3d899596 | 776 | retval = -ENOMEM; |
1da177e4 | 777 | goto bus_devices_fail; |
3d899596 | 778 | } |
1da177e4 | 779 | |
c6f7e72a GKH |
780 | priv->drivers_kset = kset_create_and_add("drivers", NULL, |
781 | &priv->subsys.kobj); | |
782 | if (!priv->drivers_kset) { | |
6dcec251 | 783 | retval = -ENOMEM; |
1da177e4 | 784 | goto bus_drivers_fail; |
6dcec251 | 785 | } |
465c7a3a | 786 | |
ca22e56d KS |
787 | INIT_LIST_HEAD(&priv->interfaces); |
788 | __mutex_init(&priv->mutex, "subsys mutex", key); | |
c6f7e72a GKH |
789 | klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put); |
790 | klist_init(&priv->klist_drivers, NULL, NULL); | |
b8c5cec2 | 791 | |
b8c5cec2 KS |
792 | retval = add_probe_files(bus); |
793 | if (retval) | |
794 | goto bus_probe_files_fail; | |
795 | ||
12478ba0 GKH |
796 | retval = bus_add_groups(bus, bus->bus_groups); |
797 | if (retval) | |
798 | goto bus_groups_fail; | |
1da177e4 | 799 | |
7dc72b28 | 800 | pr_debug("bus: '%s': registered\n", bus->name); |
1da177e4 LT |
801 | return 0; |
802 | ||
12478ba0 | 803 | bus_groups_fail: |
b8c5cec2 KS |
804 | remove_probe_files(bus); |
805 | bus_probe_files_fail: | |
c6f7e72a | 806 | kset_unregister(bus->p->drivers_kset); |
1da177e4 | 807 | bus_drivers_fail: |
c6f7e72a | 808 | kset_unregister(bus->p->devices_kset); |
1da177e4 | 809 | bus_devices_fail: |
7ac1cf4a KS |
810 | bus_remove_file(bus, &bus_attr_uevent); |
811 | bus_uevent_fail: | |
c6f7e72a | 812 | kset_unregister(&bus->p->subsys); |
1da177e4 | 813 | out: |
600c20f3 | 814 | kfree(bus->p); |
f48f3feb | 815 | bus->p = NULL; |
1da177e4 LT |
816 | return retval; |
817 | } | |
be871b7e | 818 | EXPORT_SYMBOL_GPL(bus_register); |
1da177e4 | 819 | |
1da177e4 | 820 | /** |
4a3ad20c GKH |
821 | * bus_unregister - remove a bus from the system |
822 | * @bus: bus. | |
1da177e4 | 823 | * |
4a3ad20c GKH |
824 | * Unregister the child subsystems and the bus itself. |
825 | * Finally, we call bus_put() to release the refcount | |
1da177e4 | 826 | */ |
4a3ad20c | 827 | void bus_unregister(struct bus_type *bus) |
1da177e4 | 828 | { |
7dc72b28 | 829 | pr_debug("bus: '%s': unregistering\n", bus->name); |
ca22e56d KS |
830 | if (bus->dev_root) |
831 | device_unregister(bus->dev_root); | |
12478ba0 | 832 | bus_remove_groups(bus, bus->bus_groups); |
b8c5cec2 | 833 | remove_probe_files(bus); |
c6f7e72a GKH |
834 | kset_unregister(bus->p->drivers_kset); |
835 | kset_unregister(bus->p->devices_kset); | |
7ac1cf4a | 836 | bus_remove_file(bus, &bus_attr_uevent); |
c6f7e72a | 837 | kset_unregister(&bus->p->subsys); |
1da177e4 | 838 | } |
4a3ad20c | 839 | EXPORT_SYMBOL_GPL(bus_unregister); |
1da177e4 | 840 | |
116af378 BH |
841 | int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb) |
842 | { | |
c6f7e72a | 843 | return blocking_notifier_chain_register(&bus->p->bus_notifier, nb); |
116af378 BH |
844 | } |
845 | EXPORT_SYMBOL_GPL(bus_register_notifier); | |
846 | ||
847 | int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb) | |
848 | { | |
c6f7e72a | 849 | return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb); |
116af378 BH |
850 | } |
851 | EXPORT_SYMBOL_GPL(bus_unregister_notifier); | |
852 | ||
0fed80f7 GKH |
853 | struct kset *bus_get_kset(struct bus_type *bus) |
854 | { | |
c6f7e72a | 855 | return &bus->p->subsys; |
0fed80f7 GKH |
856 | } |
857 | EXPORT_SYMBOL_GPL(bus_get_kset); | |
858 | ||
8afbb427 | 859 | static struct klist *bus_get_device_klist(struct bus_type *bus) |
b249072e | 860 | { |
c6f7e72a | 861 | return &bus->p->klist_devices; |
b249072e | 862 | } |
b249072e | 863 | |
99178b03 | 864 | /* |
dca25ebd | 865 | * Yes, this forcibly breaks the klist abstraction temporarily. It |
99178b03 GKH |
866 | * just wants to sort the klist, not change reference counts and |
867 | * take/drop locks rapidly in the process. It does all this while | |
868 | * holding the lock for the list, so objects can't otherwise be | |
869 | * added/removed while we're swizzling. | |
870 | */ | |
871 | static void device_insertion_sort_klist(struct device *a, struct list_head *list, | |
872 | int (*compare)(const struct device *a, | |
873 | const struct device *b)) | |
874 | { | |
99178b03 | 875 | struct klist_node *n; |
ae1b4171 | 876 | struct device_private *dev_prv; |
99178b03 GKH |
877 | struct device *b; |
878 | ||
4c62785e | 879 | list_for_each_entry(n, list, n_node) { |
ae1b4171 GKH |
880 | dev_prv = to_device_private_bus(n); |
881 | b = dev_prv->device; | |
99178b03 | 882 | if (compare(a, b) <= 0) { |
ae1b4171 GKH |
883 | list_move_tail(&a->p->knode_bus.n_node, |
884 | &b->p->knode_bus.n_node); | |
99178b03 GKH |
885 | return; |
886 | } | |
887 | } | |
ae1b4171 | 888 | list_move_tail(&a->p->knode_bus.n_node, list); |
99178b03 GKH |
889 | } |
890 | ||
891 | void bus_sort_breadthfirst(struct bus_type *bus, | |
892 | int (*compare)(const struct device *a, | |
893 | const struct device *b)) | |
894 | { | |
895 | LIST_HEAD(sorted_devices); | |
4c62785e | 896 | struct klist_node *n, *tmp; |
ae1b4171 | 897 | struct device_private *dev_prv; |
99178b03 GKH |
898 | struct device *dev; |
899 | struct klist *device_klist; | |
900 | ||
901 | device_klist = bus_get_device_klist(bus); | |
902 | ||
903 | spin_lock(&device_klist->k_lock); | |
4c62785e | 904 | list_for_each_entry_safe(n, tmp, &device_klist->k_list, n_node) { |
ae1b4171 GKH |
905 | dev_prv = to_device_private_bus(n); |
906 | dev = dev_prv->device; | |
99178b03 GKH |
907 | device_insertion_sort_klist(dev, &sorted_devices, compare); |
908 | } | |
909 | list_splice(&sorted_devices, &device_klist->k_list); | |
910 | spin_unlock(&device_klist->k_lock); | |
911 | } | |
912 | EXPORT_SYMBOL_GPL(bus_sort_breadthfirst); | |
913 | ||
ca22e56d KS |
914 | /** |
915 | * subsys_dev_iter_init - initialize subsys device iterator | |
916 | * @iter: subsys iterator to initialize | |
917 | * @subsys: the subsys we wanna iterate over | |
918 | * @start: the device to start iterating from, if any | |
919 | * @type: device_type of the devices to iterate over, NULL for all | |
920 | * | |
921 | * Initialize subsys iterator @iter such that it iterates over devices | |
922 | * of @subsys. If @start is set, the list iteration will start there, | |
923 | * otherwise if it is NULL, the iteration starts at the beginning of | |
924 | * the list. | |
925 | */ | |
2e45fc55 GKH |
926 | static void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys, |
927 | struct device *start, const struct device_type *type) | |
ca22e56d KS |
928 | { |
929 | struct klist_node *start_knode = NULL; | |
930 | ||
931 | if (start) | |
932 | start_knode = &start->p->knode_bus; | |
7cd9c9bb GKH |
933 | klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode); |
934 | iter->type = type; | |
ca22e56d | 935 | } |
ca22e56d KS |
936 | |
937 | /** | |
938 | * subsys_dev_iter_next - iterate to the next device | |
939 | * @iter: subsys iterator to proceed | |
940 | * | |
941 | * Proceed @iter to the next device and return it. Returns NULL if | |
942 | * iteration is complete. | |
943 | * | |
944 | * The returned device is referenced and won't be released till | |
945 | * iterator is proceed to the next device or exited. The caller is | |
946 | * free to do whatever it wants to do with the device including | |
947 | * calling back into subsys code. | |
948 | */ | |
38cdadef | 949 | static struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter) |
ca22e56d KS |
950 | { |
951 | struct klist_node *knode; | |
952 | struct device *dev; | |
953 | ||
954 | for (;;) { | |
955 | knode = klist_next(&iter->ki); | |
956 | if (!knode) | |
957 | return NULL; | |
371fd7a2 | 958 | dev = to_device_private_bus(knode)->device; |
ca22e56d KS |
959 | if (!iter->type || iter->type == dev->type) |
960 | return dev; | |
961 | } | |
962 | } | |
ca22e56d KS |
963 | |
964 | /** | |
965 | * subsys_dev_iter_exit - finish iteration | |
966 | * @iter: subsys iterator to finish | |
967 | * | |
968 | * Finish an iteration. Always call this function after iteration is | |
969 | * complete whether the iteration ran till the end or not. | |
970 | */ | |
971 | void subsys_dev_iter_exit(struct subsys_dev_iter *iter) | |
972 | { | |
973 | klist_iter_exit(&iter->ki); | |
974 | } | |
975 | EXPORT_SYMBOL_GPL(subsys_dev_iter_exit); | |
976 | ||
977 | int subsys_interface_register(struct subsys_interface *sif) | |
978 | { | |
979 | struct bus_type *subsys; | |
980 | struct subsys_dev_iter iter; | |
981 | struct device *dev; | |
982 | ||
983 | if (!sif || !sif->subsys) | |
984 | return -ENODEV; | |
985 | ||
986 | subsys = bus_get(sif->subsys); | |
987 | if (!subsys) | |
988 | return -EINVAL; | |
989 | ||
990 | mutex_lock(&subsys->p->mutex); | |
991 | list_add_tail(&sif->node, &subsys->p->interfaces); | |
992 | if (sif->add_dev) { | |
993 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
994 | while ((dev = subsys_dev_iter_next(&iter))) | |
995 | sif->add_dev(dev, sif); | |
996 | subsys_dev_iter_exit(&iter); | |
997 | } | |
998 | mutex_unlock(&subsys->p->mutex); | |
999 | ||
1000 | return 0; | |
1001 | } | |
1002 | EXPORT_SYMBOL_GPL(subsys_interface_register); | |
1003 | ||
1004 | void subsys_interface_unregister(struct subsys_interface *sif) | |
1005 | { | |
2b31594a | 1006 | struct bus_type *subsys; |
ca22e56d KS |
1007 | struct subsys_dev_iter iter; |
1008 | struct device *dev; | |
1009 | ||
2b31594a | 1010 | if (!sif || !sif->subsys) |
ca22e56d KS |
1011 | return; |
1012 | ||
2b31594a JC |
1013 | subsys = sif->subsys; |
1014 | ||
ca22e56d KS |
1015 | mutex_lock(&subsys->p->mutex); |
1016 | list_del_init(&sif->node); | |
1017 | if (sif->remove_dev) { | |
1018 | subsys_dev_iter_init(&iter, subsys, NULL, NULL); | |
1019 | while ((dev = subsys_dev_iter_next(&iter))) | |
1020 | sif->remove_dev(dev, sif); | |
1021 | subsys_dev_iter_exit(&iter); | |
1022 | } | |
1023 | mutex_unlock(&subsys->p->mutex); | |
1024 | ||
1025 | bus_put(subsys); | |
1026 | } | |
1027 | EXPORT_SYMBOL_GPL(subsys_interface_unregister); | |
1028 | ||
1029 | static void system_root_device_release(struct device *dev) | |
1030 | { | |
1031 | kfree(dev); | |
1032 | } | |
d73ce004 TH |
1033 | |
1034 | static int subsys_register(struct bus_type *subsys, | |
1035 | const struct attribute_group **groups, | |
1036 | struct kobject *parent_of_root) | |
ca22e56d KS |
1037 | { |
1038 | struct device *dev; | |
1039 | int err; | |
1040 | ||
1041 | err = bus_register(subsys); | |
1042 | if (err < 0) | |
1043 | return err; | |
1044 | ||
1045 | dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
1046 | if (!dev) { | |
1047 | err = -ENOMEM; | |
1048 | goto err_dev; | |
1049 | } | |
1050 | ||
1051 | err = dev_set_name(dev, "%s", subsys->name); | |
1052 | if (err < 0) | |
1053 | goto err_name; | |
1054 | ||
d73ce004 | 1055 | dev->kobj.parent = parent_of_root; |
ca22e56d KS |
1056 | dev->groups = groups; |
1057 | dev->release = system_root_device_release; | |
1058 | ||
1059 | err = device_register(dev); | |
1060 | if (err < 0) | |
1061 | goto err_dev_reg; | |
1062 | ||
1063 | subsys->dev_root = dev; | |
1064 | return 0; | |
1065 | ||
1066 | err_dev_reg: | |
1067 | put_device(dev); | |
1068 | dev = NULL; | |
1069 | err_name: | |
1070 | kfree(dev); | |
1071 | err_dev: | |
1072 | bus_unregister(subsys); | |
1073 | return err; | |
1074 | } | |
d73ce004 TH |
1075 | |
1076 | /** | |
1077 | * subsys_system_register - register a subsystem at /sys/devices/system/ | |
1078 | * @subsys: system subsystem | |
1079 | * @groups: default attributes for the root device | |
1080 | * | |
1081 | * All 'system' subsystems have a /sys/devices/system/<name> root device | |
1082 | * with the name of the subsystem. The root device can carry subsystem- | |
1083 | * wide attributes. All registered devices are below this single root | |
1084 | * device and are named after the subsystem with a simple enumeration | |
e227867f | 1085 | * number appended. The registered devices are not explicitly named; |
d73ce004 TH |
1086 | * only 'id' in the device needs to be set. |
1087 | * | |
1088 | * Do not use this interface for anything new, it exists for compatibility | |
1089 | * with bad ideas only. New subsystems should use plain subsystems; and | |
1090 | * add the subsystem-wide attributes should be added to the subsystem | |
1091 | * directory itself and not some create fake root-device placed in | |
1092 | * /sys/devices/system/<name>. | |
1093 | */ | |
1094 | int subsys_system_register(struct bus_type *subsys, | |
1095 | const struct attribute_group **groups) | |
1096 | { | |
1097 | return subsys_register(subsys, groups, &system_kset->kobj); | |
1098 | } | |
ca22e56d KS |
1099 | EXPORT_SYMBOL_GPL(subsys_system_register); |
1100 | ||
d73ce004 TH |
1101 | /** |
1102 | * subsys_virtual_register - register a subsystem at /sys/devices/virtual/ | |
1103 | * @subsys: virtual subsystem | |
1104 | * @groups: default attributes for the root device | |
1105 | * | |
1106 | * All 'virtual' subsystems have a /sys/devices/system/<name> root device | |
1107 | * with the name of the subystem. The root device can carry subsystem-wide | |
1108 | * attributes. All registered devices are below this single root device. | |
1109 | * There's no restriction on device naming. This is for kernel software | |
1110 | * constructs which need sysfs interface. | |
1111 | */ | |
1112 | int subsys_virtual_register(struct bus_type *subsys, | |
1113 | const struct attribute_group **groups) | |
1114 | { | |
1115 | struct kobject *virtual_dir; | |
1116 | ||
1117 | virtual_dir = virtual_device_parent(NULL); | |
1118 | if (!virtual_dir) | |
1119 | return -ENOMEM; | |
1120 | ||
1121 | return subsys_register(subsys, groups, virtual_dir); | |
1122 | } | |
1c04fc35 | 1123 | EXPORT_SYMBOL_GPL(subsys_virtual_register); |
d73ce004 | 1124 | |
1da177e4 LT |
1125 | int __init buses_init(void) |
1126 | { | |
59a54833 GKH |
1127 | bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL); |
1128 | if (!bus_kset) | |
1129 | return -ENOMEM; | |
ca22e56d KS |
1130 | |
1131 | system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj); | |
1132 | if (!system_kset) | |
1133 | return -ENOMEM; | |
1134 | ||
59a54833 | 1135 | return 0; |
1da177e4 | 1136 | } |