blob: ef522ae5548092f83ddabcbf36d7a54ad56f7282 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * bus.c - bus driver management
3 *
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -08006 * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (c) 2007 Novell Inc.
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 *
9 * This file is released under the GPLv2
10 *
11 */
12
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/device.h>
14#include <linux/module.h>
15#include <linux/errno.h>
16#include <linux/init.h>
17#include <linux/string.h>
18#include "base.h"
19#include "power/power.h"
20
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -070022#define to_bus(obj) container_of(obj, struct bus_type_private, subsys.kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
24/*
25 * sysfs bindings for drivers
26 */
27
28#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
30
Kay Sieversb8c5cec2007-02-16 17:33:36 +010031static int __must_check bus_rescan_devices_helper(struct device *dev,
32 void *data);
33
Greg Kroah-Hartman5901d012007-09-13 02:53:13 -070034static struct bus_type *bus_get(struct bus_type *bus)
35{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -070036 if (bus) {
37 kset_get(&bus->p->subsys);
38 return bus;
39 }
40 return NULL;
Greg Kroah-Hartman5901d012007-09-13 02:53:13 -070041}
42
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -070043static void bus_put(struct bus_type *bus)
44{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -070045 if (bus)
46 kset_put(&bus->p->subsys);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -070047}
48
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080049static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr,
50 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080052 struct driver_attribute *drv_attr = to_drv_attr(attr);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080053 struct driver_private *drv_priv = to_driver(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050054 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
56 if (drv_attr->show)
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080057 ret = drv_attr->show(drv_priv->driver, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 return ret;
59}
60
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080061static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr,
62 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -070063{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080064 struct driver_attribute *drv_attr = to_drv_attr(attr);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080065 struct driver_private *drv_priv = to_driver(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050066 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
68 if (drv_attr->store)
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080069 ret = drv_attr->store(drv_priv->driver, buf, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 return ret;
71}
72
73static struct sysfs_ops driver_sysfs_ops = {
74 .show = drv_attr_show,
75 .store = drv_attr_store,
76};
77
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080078static void driver_release(struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -070079{
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080080 struct driver_private *drv_priv = to_driver(kobj);
81
Harvey Harrison2b3a3022008-03-04 16:41:05 -080082 pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -080083 kfree(drv_priv);
Linus Torvalds1da177e2005-04-16 15:20:36 -070084}
85
Greg Kroah-Hartmana1148fb2007-10-11 10:47:49 -060086static struct kobj_type driver_ktype = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 .sysfs_ops = &driver_sysfs_ops,
88 .release = driver_release,
89};
90
Linus Torvalds1da177e2005-04-16 15:20:36 -070091/*
92 * sysfs bindings for buses
93 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080094static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr,
95 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -070096{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080097 struct bus_attribute *bus_attr = to_bus_attr(attr);
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -070098 struct bus_type_private *bus_priv = to_bus(kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 ssize_t ret = 0;
100
101 if (bus_attr->show)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700102 ret = bus_attr->show(bus_priv->bus, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 return ret;
104}
105
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800106static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr,
107 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800109 struct bus_attribute *bus_attr = to_bus_attr(attr);
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700110 struct bus_type_private *bus_priv = to_bus(kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 ssize_t ret = 0;
112
113 if (bus_attr->store)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700114 ret = bus_attr->store(bus_priv->bus, buf, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 return ret;
116}
117
118static struct sysfs_ops bus_sysfs_ops = {
119 .show = bus_attr_show,
120 .store = bus_attr_store,
121};
122
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800123int bus_create_file(struct bus_type *bus, struct bus_attribute *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124{
125 int error;
Greg Kroah-Hartman5901d012007-09-13 02:53:13 -0700126 if (bus_get(bus)) {
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700127 error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700128 bus_put(bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 } else
130 error = -EINVAL;
131 return error;
132}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800133EXPORT_SYMBOL_GPL(bus_create_file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800135void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136{
Greg Kroah-Hartman5901d012007-09-13 02:53:13 -0700137 if (bus_get(bus)) {
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700138 sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700139 bus_put(bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 }
141}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800142EXPORT_SYMBOL_GPL(bus_remove_file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
Kay Sievers80f03e32007-05-26 11:21:36 +0200144static struct kobj_type bus_ktype = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 .sysfs_ops = &bus_sysfs_ops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146};
147
Kay Sievers80f03e32007-05-26 11:21:36 +0200148static int bus_uevent_filter(struct kset *kset, struct kobject *kobj)
149{
150 struct kobj_type *ktype = get_ktype(kobj);
151
152 if (ktype == &bus_ktype)
153 return 1;
154 return 0;
155}
156
157static struct kset_uevent_ops bus_uevent_ops = {
158 .filter = bus_uevent_filter,
159};
160
Greg Kroah-Hartman59a54832007-10-29 23:22:26 -0500161static struct kset *bus_kset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
Russell King2139bdd2006-02-07 12:58:20 -0800164#ifdef CONFIG_HOTPLUG
Alan Stern2b08c8d2005-11-23 15:43:50 -0800165/* Manually detach a device from its associated driver. */
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700166static ssize_t driver_unbind(struct device_driver *drv,
167 const char *buf, size_t count)
168{
Greg Kroah-Hartman5901d012007-09-13 02:53:13 -0700169 struct bus_type *bus = bus_get(drv->bus);
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700170 struct device *dev;
171 int err = -ENODEV;
172
Greg Kroah-Hartman1f9ffc02008-01-27 10:29:20 -0800173 dev = bus_find_device_by_name(bus, NULL, buf);
Alan Stern2b08c8d2005-11-23 15:43:50 -0800174 if (dev && dev->driver == drv) {
Alan Sternbf74ad52005-11-17 16:54:12 -0500175 if (dev->parent) /* Needed for USB */
176 down(&dev->parent->sem);
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700177 device_release_driver(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500178 if (dev->parent)
179 up(&dev->parent->sem);
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700180 err = count;
181 }
Alan Stern2b08c8d2005-11-23 15:43:50 -0800182 put_device(dev);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700183 bus_put(bus);
Alan Stern2b08c8d2005-11-23 15:43:50 -0800184 return err;
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700185}
186static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind);
187
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700188/*
189 * Manually attach a device to a driver.
190 * Note: the driver must want to bind to the device,
191 * it is not possible to override the driver's id table.
192 */
193static ssize_t driver_bind(struct device_driver *drv,
194 const char *buf, size_t count)
195{
Greg Kroah-Hartman5901d012007-09-13 02:53:13 -0700196 struct bus_type *bus = bus_get(drv->bus);
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700197 struct device *dev;
198 int err = -ENODEV;
199
Greg Kroah-Hartman1f9ffc02008-01-27 10:29:20 -0800200 dev = bus_find_device_by_name(bus, NULL, buf);
Alan Stern2b08c8d2005-11-23 15:43:50 -0800201 if (dev && dev->driver == NULL) {
Alan Sternbf74ad52005-11-17 16:54:12 -0500202 if (dev->parent) /* Needed for USB */
203 down(&dev->parent->sem);
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700204 down(&dev->sem);
205 err = driver_probe_device(drv, dev);
206 up(&dev->sem);
Alan Sternbf74ad52005-11-17 16:54:12 -0500207 if (dev->parent)
208 up(&dev->parent->sem);
Ryan Wilson37225402006-03-22 16:26:25 -0500209
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800210 if (err > 0) {
211 /* success */
Ryan Wilson37225402006-03-22 16:26:25 -0500212 err = count;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800213 } else if (err == 0) {
214 /* driver didn't accept device */
Ryan Wilson37225402006-03-22 16:26:25 -0500215 err = -ENODEV;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800216 }
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700217 }
Alan Stern2b08c8d2005-11-23 15:43:50 -0800218 put_device(dev);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700219 bus_put(bus);
Alan Stern2b08c8d2005-11-23 15:43:50 -0800220 return err;
Greg Kroah-Hartmanafdce752005-06-22 16:09:05 -0700221}
222static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind);
223
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100224static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf)
225{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700226 return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100227}
228
229static ssize_t store_drivers_autoprobe(struct bus_type *bus,
230 const char *buf, size_t count)
231{
232 if (buf[0] == '0')
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700233 bus->p->drivers_autoprobe = 0;
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100234 else
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700235 bus->p->drivers_autoprobe = 1;
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100236 return count;
237}
238
239static ssize_t store_drivers_probe(struct bus_type *bus,
240 const char *buf, size_t count)
241{
242 struct device *dev;
243
Greg Kroah-Hartman1f9ffc02008-01-27 10:29:20 -0800244 dev = bus_find_device_by_name(bus, NULL, buf);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100245 if (!dev)
246 return -ENODEV;
247 if (bus_rescan_devices_helper(dev, NULL) != 0)
248 return -EINVAL;
249 return count;
250}
Russell King2139bdd2006-02-07 12:58:20 -0800251#endif
Greg Kroah-Hartman151ef382005-06-22 16:09:05 -0700252
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800253static struct device *next_device(struct klist_iter *i)
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800254{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800255 struct klist_node *n = klist_next(i);
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800256 return n ? container_of(n, struct device, knode_bus) : NULL;
257}
258
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800260 * bus_for_each_dev - device iterator.
261 * @bus: bus type.
262 * @start: device to start iterating from.
263 * @data: data for the callback.
264 * @fn: function to be called for each device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800266 * Iterate over @bus's list of devices, and call @fn for each,
267 * passing it @data. If @start is not NULL, we use that device to
268 * begin iterating from.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800270 * We check the return of @fn each time. If it returns anything
271 * other than 0, we break out and return that value.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800273 * NOTE: The device that returns a non-zero value is not retained
274 * in any way, nor is its refcount incremented. If the caller needs
275 * to retain this data, it should do, and increment the reference
276 * count in the supplied callback.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800278int bus_for_each_dev(struct bus_type *bus, struct device *start,
279 void *data, int (*fn)(struct device *, void *))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280{
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800281 struct klist_iter i;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800282 struct device *dev;
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800283 int error = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800285 if (!bus)
286 return -EINVAL;
287
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700288 klist_iter_init_node(&bus->p->klist_devices, &i,
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800289 (start ? &start->knode_bus : NULL));
290 while ((dev = next_device(&i)) && !error)
291 error = fn(dev, data);
292 klist_iter_exit(&i);
293 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800295EXPORT_SYMBOL_GPL(bus_for_each_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296
Cornelia Huck0edb5862005-06-22 16:59:51 +0200297/**
298 * bus_find_device - device iterator for locating a particular device.
299 * @bus: bus type
300 * @start: Device to begin with
301 * @data: Data to pass to match function
302 * @match: Callback function to check device
303 *
304 * This is similar to the bus_for_each_dev() function above, but it
305 * returns a reference to a device that is 'found' for later use, as
306 * determined by the @match callback.
307 *
308 * The callback should return 0 if the device doesn't match and non-zero
309 * if it does. If the callback returns non-zero, this function will
310 * return to the caller and not iterate over any more devices.
311 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800312struct device *bus_find_device(struct bus_type *bus,
313 struct device *start, void *data,
314 int (*match)(struct device *dev, void *data))
Cornelia Huck0edb5862005-06-22 16:59:51 +0200315{
316 struct klist_iter i;
317 struct device *dev;
318
319 if (!bus)
320 return NULL;
321
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700322 klist_iter_init_node(&bus->p->klist_devices, &i,
Cornelia Huck0edb5862005-06-22 16:59:51 +0200323 (start ? &start->knode_bus : NULL));
324 while ((dev = next_device(&i)))
325 if (match(dev, data) && get_device(dev))
326 break;
327 klist_iter_exit(&i);
328 return dev;
329}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800330EXPORT_SYMBOL_GPL(bus_find_device);
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800331
Greg Kroah-Hartman1f9ffc02008-01-27 10:29:20 -0800332static int match_name(struct device *dev, void *data)
333{
334 const char *name = data;
335
336 if (strcmp(name, dev->bus_id) == 0)
337 return 1;
338 return 0;
339}
340
341/**
342 * bus_find_device_by_name - device iterator for locating a particular device of a specific name
343 * @bus: bus type
344 * @start: Device to begin with
345 * @name: name of the device to match
346 *
347 * This is similar to the bus_find_device() function above, but it handles
348 * searching by a name automatically, no need to write another strcmp matching
349 * function.
350 */
351struct device *bus_find_device_by_name(struct bus_type *bus,
352 struct device *start, const char *name)
353{
354 return bus_find_device(bus, start, (void *)name, match_name);
355}
356EXPORT_SYMBOL_GPL(bus_find_device_by_name);
357
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800358static struct device_driver *next_driver(struct klist_iter *i)
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800359{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800360 struct klist_node *n = klist_next(i);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800361 struct driver_private *drv_priv;
362
363 if (n) {
364 drv_priv = container_of(n, struct driver_private, knode_bus);
365 return drv_priv->driver;
366 }
367 return NULL;
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800368}
369
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800371 * bus_for_each_drv - driver iterator
372 * @bus: bus we're dealing with.
373 * @start: driver to start iterating on.
374 * @data: data to pass to the callback.
375 * @fn: function to call for each driver.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800377 * This is nearly identical to the device iterator above.
378 * We iterate over each driver that belongs to @bus, and call
379 * @fn for each. If @fn returns anything but 0, we break out
380 * and return it. If @start is not NULL, we use it as the head
381 * of the list.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800383 * NOTE: we don't return the driver that returns a non-zero
384 * value, nor do we leave the reference count incremented for that
385 * driver. If the caller needs to know that info, it must set it
386 * in the callback. It must also be sure to increment the refcount
387 * so it doesn't disappear before returning to the caller.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800389int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
390 void *data, int (*fn)(struct device_driver *, void *))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391{
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800392 struct klist_iter i;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800393 struct device_driver *drv;
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800394 int error = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800396 if (!bus)
397 return -EINVAL;
398
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700399 klist_iter_init_node(&bus->p->klist_drivers, &i,
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800400 start ? &start->p->knode_bus : NULL);
mochel@digitalimplant.org38fdac32005-03-21 12:00:18 -0800401 while ((drv = next_driver(&i)) && !error)
402 error = fn(drv, data);
403 klist_iter_exit(&i);
404 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800406EXPORT_SYMBOL_GPL(bus_for_each_drv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407
Andrew Morton4aca67e2007-02-13 22:39:26 -0800408static int device_add_attrs(struct bus_type *bus, struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409{
410 int error = 0;
411 int i;
412
Andrew Morton4aca67e2007-02-13 22:39:26 -0800413 if (!bus->dev_attrs)
414 return 0;
415
416 for (i = 0; attr_name(bus->dev_attrs[i]); i++) {
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800417 error = device_create_file(dev, &bus->dev_attrs[i]);
Andrew Morton4aca67e2007-02-13 22:39:26 -0800418 if (error) {
419 while (--i >= 0)
420 device_remove_file(dev, &bus->dev_attrs[i]);
421 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 }
423 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425}
426
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800427static void device_remove_attrs(struct bus_type *bus, struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428{
429 int i;
430
431 if (bus->dev_attrs) {
432 for (i = 0; attr_name(bus->dev_attrs[i]); i++)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800433 device_remove_file(dev, &bus->dev_attrs[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 }
435}
436
Kay Sieversb9cafc72006-09-14 11:23:28 +0200437#ifdef CONFIG_SYSFS_DEPRECATED
438static int make_deprecated_bus_links(struct device *dev)
439{
440 return sysfs_create_link(&dev->kobj,
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700441 &dev->bus->p->subsys.kobj, "bus");
Kay Sieversb9cafc72006-09-14 11:23:28 +0200442}
443
444static void remove_deprecated_bus_links(struct device *dev)
445{
446 sysfs_remove_link(&dev->kobj, "bus");
447}
448#else
449static inline int make_deprecated_bus_links(struct device *dev) { return 0; }
450static inline void remove_deprecated_bus_links(struct device *dev) { }
451#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452
453/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800454 * bus_add_device - add device to bus
455 * @dev: device being added
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800457 * - Add the device to its bus's list of devices.
458 * - Create link to device's bus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800460int bus_add_device(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800462 struct bus_type *bus = bus_get(dev->bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 int error = 0;
464
465 if (bus) {
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800466 pr_debug("bus: '%s': add device %s\n", bus->name, dev->bus_id);
Greg Kroah-Hartmand377e852005-06-22 16:09:05 -0700467 error = device_add_attrs(bus, dev);
Andrew Mortonf86db392006-08-14 22:43:20 -0700468 if (error)
Cornelia Huck513e7332006-09-22 11:37:08 +0200469 goto out_put;
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700470 error = sysfs_create_link(&bus->p->devices_kset->kobj,
Andrew Mortonf86db392006-08-14 22:43:20 -0700471 &dev->kobj, dev->bus_id);
472 if (error)
Cornelia Huck513e7332006-09-22 11:37:08 +0200473 goto out_id;
Andrew Mortonf86db392006-08-14 22:43:20 -0700474 error = sysfs_create_link(&dev->kobj,
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700475 &dev->bus->p->subsys.kobj, "subsystem");
Andrew Mortonf86db392006-08-14 22:43:20 -0700476 if (error)
Cornelia Huck513e7332006-09-22 11:37:08 +0200477 goto out_subsys;
Kay Sieversb9cafc72006-09-14 11:23:28 +0200478 error = make_deprecated_bus_links(dev);
Cornelia Huck513e7332006-09-22 11:37:08 +0200479 if (error)
480 goto out_deprecated;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 }
Cornelia Huck513e7332006-09-22 11:37:08 +0200482 return 0;
483
484out_deprecated:
485 sysfs_remove_link(&dev->kobj, "subsystem");
486out_subsys:
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700487 sysfs_remove_link(&bus->p->devices_kset->kobj, dev->bus_id);
Cornelia Huck513e7332006-09-22 11:37:08 +0200488out_id:
489 device_remove_attrs(bus, dev);
490out_put:
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700491 bus_put(dev->bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 return error;
493}
494
495/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800496 * bus_attach_device - add device to bus
497 * @dev: device tried to attach to a driver
Kay Sievers53877d02006-04-04 20:42:26 +0200498 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800499 * - Add device to bus's list of devices.
500 * - Try to attach to driver.
Kay Sievers53877d02006-04-04 20:42:26 +0200501 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800502void bus_attach_device(struct device *dev)
Kay Sievers53877d02006-04-04 20:42:26 +0200503{
Andrew Mortonf86db392006-08-14 22:43:20 -0700504 struct bus_type *bus = dev->bus;
505 int ret = 0;
Kay Sievers53877d02006-04-04 20:42:26 +0200506
507 if (bus) {
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700508 if (bus->p->drivers_autoprobe)
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100509 ret = device_attach(dev);
Cornelia Huckc6a46692007-02-05 16:15:26 -0800510 WARN_ON(ret < 0);
511 if (ret >= 0)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700512 klist_add_tail(&dev->knode_bus, &bus->p->klist_devices);
Kay Sievers53877d02006-04-04 20:42:26 +0200513 }
514}
515
516/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800517 * bus_remove_device - remove device from bus
518 * @dev: device to be removed
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800520 * - Remove symlink from bus's directory.
521 * - Delete device from bus's list.
522 * - Detach from its driver.
523 * - Drop reference taken in bus_add_device().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800525void bus_remove_device(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526{
527 if (dev->bus) {
Kay Sieversb9d9c822006-06-15 15:31:56 +0200528 sysfs_remove_link(&dev->kobj, "subsystem");
Kay Sieversb9cafc72006-09-14 11:23:28 +0200529 remove_deprecated_bus_links(dev);
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800530 sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
531 dev->bus_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532 device_remove_attrs(dev->bus, dev);
Rafael J. Wysocki29591b92008-04-22 22:57:50 +0200533 if (klist_node_attached(&dev->knode_bus))
534 klist_del(&dev->knode_bus);
Greg Kroah-Hartman3f62e572008-03-13 17:07:03 -0400535
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800536 pr_debug("bus: '%s': remove device %s\n",
537 dev->bus->name, dev->bus_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 device_release_driver(dev);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700539 bus_put(dev->bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 }
541}
542
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800543static int driver_add_attrs(struct bus_type *bus, struct device_driver *drv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544{
545 int error = 0;
546 int i;
547
548 if (bus->drv_attrs) {
549 for (i = 0; attr_name(bus->drv_attrs[i]); i++) {
550 error = driver_create_file(drv, &bus->drv_attrs[i]);
551 if (error)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800552 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 }
554 }
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800555done:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 return error;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800557err:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 while (--i >= 0)
559 driver_remove_file(drv, &bus->drv_attrs[i]);
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800560 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561}
562
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800563static void driver_remove_attrs(struct bus_type *bus,
564 struct device_driver *drv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565{
566 int i;
567
568 if (bus->drv_attrs) {
569 for (i = 0; attr_name(bus->drv_attrs[i]); i++)
570 driver_remove_file(drv, &bus->drv_attrs[i]);
571 }
572}
573
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800574#ifdef CONFIG_HOTPLUG
575/*
576 * Thanks to drivers making their tables __devinit, we can't allow manual
577 * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled.
578 */
Andrew Mortonf86db392006-08-14 22:43:20 -0700579static int __must_check add_bind_files(struct device_driver *drv)
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800580{
Andrew Mortonf86db392006-08-14 22:43:20 -0700581 int ret;
582
583 ret = driver_create_file(drv, &driver_attr_unbind);
584 if (ret == 0) {
585 ret = driver_create_file(drv, &driver_attr_bind);
586 if (ret)
587 driver_remove_file(drv, &driver_attr_unbind);
588 }
589 return ret;
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800590}
591
592static void remove_bind_files(struct device_driver *drv)
593{
594 driver_remove_file(drv, &driver_attr_bind);
595 driver_remove_file(drv, &driver_attr_unbind);
596}
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100597
Kay Sievers83807702007-07-30 02:28:56 +0200598static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe);
599static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO,
600 show_drivers_autoprobe, store_drivers_autoprobe);
601
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100602static int add_probe_files(struct bus_type *bus)
603{
604 int retval;
605
Kay Sievers83807702007-07-30 02:28:56 +0200606 retval = bus_create_file(bus, &bus_attr_drivers_probe);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100607 if (retval)
608 goto out;
609
Kay Sievers83807702007-07-30 02:28:56 +0200610 retval = bus_create_file(bus, &bus_attr_drivers_autoprobe);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100611 if (retval)
Kay Sievers83807702007-07-30 02:28:56 +0200612 bus_remove_file(bus, &bus_attr_drivers_probe);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100613out:
614 return retval;
615}
616
617static void remove_probe_files(struct bus_type *bus)
618{
Kay Sievers83807702007-07-30 02:28:56 +0200619 bus_remove_file(bus, &bus_attr_drivers_autoprobe);
620 bus_remove_file(bus, &bus_attr_drivers_probe);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100621}
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800622#else
Yoichi Yuasa35acfdd2006-07-15 01:30:11 +0900623static inline int add_bind_files(struct device_driver *drv) { return 0; }
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800624static inline void remove_bind_files(struct device_driver *drv) {}
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100625static inline int add_probe_files(struct bus_type *bus) { return 0; }
626static inline void remove_probe_files(struct bus_type *bus) {}
Greg Kroah-Hartman874c6242005-12-13 15:17:34 -0800627#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200629static ssize_t driver_uevent_store(struct device_driver *drv,
630 const char *buf, size_t count)
631{
632 enum kobject_action action;
633
634 if (kobject_action_type(buf, count, &action) == 0)
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800635 kobject_uevent(&drv->p->kobj, action);
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200636 return count;
637}
638static DRIVER_ATTR(uevent, S_IWUSR, NULL, driver_uevent_store);
639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800641 * bus_add_driver - Add a driver to the bus.
642 * @drv: driver.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 */
Andrew Mortonf86db392006-08-14 22:43:20 -0700644int bus_add_driver(struct device_driver *drv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645{
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800646 struct bus_type *bus;
647 struct driver_private *priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 int error = 0;
649
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800650 bus = bus_get(drv->bus);
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400651 if (!bus)
Greg Kroah-Hartman4f6e1942007-04-20 11:29:52 -0700652 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800654 pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800655
656 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
Cornelia Huck07634462008-02-18 17:04:25 +0100657 if (!priv) {
658 error = -ENOMEM;
659 goto out_put_bus;
660 }
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800661 klist_init(&priv->klist_devices, NULL, NULL);
662 priv->driver = drv;
663 drv->p = priv;
Greg Kroah-Hartmanc8e90d82007-12-17 15:54:39 -0400664 priv->kobj.kset = bus->p->drivers_kset;
665 error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,
666 "%s", drv->name);
Cornelia Huckdc0afa82007-07-09 11:39:18 -0700667 if (error)
Cornelia Huck07634462008-02-18 17:04:25 +0100668 goto out_unregister;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700670 if (drv->bus->p->drivers_autoprobe) {
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100671 error = driver_attach(drv);
672 if (error)
673 goto out_unregister;
674 }
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800675 klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400676 module_add_driver(drv->owner, drv);
677
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200678 error = driver_create_file(drv, &driver_attr_uevent);
679 if (error) {
680 printk(KERN_ERR "%s: uevent attr (%s) failed\n",
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800681 __func__, drv->name);
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200682 }
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400683 error = driver_add_attrs(bus, drv);
684 if (error) {
685 /* How the hell do we get out of this pickle? Give up */
686 printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n",
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800687 __func__, drv->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 }
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400689 error = add_bind_files(drv);
690 if (error) {
691 /* Ditto */
692 printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800693 __func__, drv->name);
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400694 }
695
Greg Kroah-Hartmanc8e90d82007-12-17 15:54:39 -0400696 kobject_uevent(&priv->kobj, KOBJ_ADD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 return error;
Andrew Mortonf86db392006-08-14 22:43:20 -0700698out_unregister:
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800699 kobject_put(&priv->kobj);
Andrew Mortonf86db392006-08-14 22:43:20 -0700700out_put_bus:
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700701 bus_put(bus);
Andrew Mortonf86db392006-08-14 22:43:20 -0700702 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703}
704
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800706 * bus_remove_driver - delete driver from bus's knowledge.
707 * @drv: driver.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800709 * Detach the driver from the devices it controls, and remove
710 * it from its bus's list of drivers. Finally, we drop the reference
711 * to the bus we took in bus_add_driver().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800713void bus_remove_driver(struct device_driver *drv)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714{
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400715 if (!drv->bus)
716 return;
717
718 remove_bind_files(drv);
719 driver_remove_attrs(drv->bus, drv);
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200720 driver_remove_file(drv, &driver_attr_uevent);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800721 klist_remove(&drv->p->knode_bus);
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800722 pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name);
Jeff Garzikd9fd4d3b32006-10-04 07:48:03 -0400723 driver_detach(drv);
724 module_remove_driver(drv);
Greg Kroah-Hartmanc10997f2007-12-20 08:13:05 -0800725 kobject_put(&drv->p->kobj);
Greg Kroah-Hartmanfc1ede52007-09-13 02:53:13 -0700726 bus_put(drv->bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727}
728
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729/* Helper for bus_rescan_devices's iter */
Andrew Mortonf86db392006-08-14 22:43:20 -0700730static int __must_check bus_rescan_devices_helper(struct device *dev,
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800731 void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732{
Andrew Mortonf86db392006-08-14 22:43:20 -0700733 int ret = 0;
734
Alan Sternbf74ad52005-11-17 16:54:12 -0500735 if (!dev->driver) {
736 if (dev->parent) /* Needed for USB */
737 down(&dev->parent->sem);
Andrew Mortonf86db392006-08-14 22:43:20 -0700738 ret = device_attach(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500739 if (dev->parent)
740 up(&dev->parent->sem);
741 }
Andrew Mortonf86db392006-08-14 22:43:20 -0700742 return ret < 0 ? ret : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743}
744
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745/**
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700746 * bus_rescan_devices - rescan devices on the bus for possible drivers
747 * @bus: the bus to scan.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 *
Greg Kroah-Hartman23d3d602005-06-22 16:09:05 -0700749 * This function will look for devices on the bus with no driver
750 * attached and rescan it against existing drivers to see if it matches
751 * any by calling device_attach() for the unbound devices.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800753int bus_rescan_devices(struct bus_type *bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754{
Andrew Mortonf86db392006-08-14 22:43:20 -0700755 return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800757EXPORT_SYMBOL_GPL(bus_rescan_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758
Moore, Erice935d5d2006-03-14 09:18:18 -0700759/**
760 * device_reprobe - remove driver for a device and probe for a new driver
761 * @dev: the device to reprobe
762 *
763 * This function detaches the attached driver (if any) for the given
764 * device and restarts the driver probing process. It is intended
765 * to use if probing criteria changed during a devices lifetime and
766 * driver attachment should change accordingly.
767 */
Andrew Mortonf86db392006-08-14 22:43:20 -0700768int device_reprobe(struct device *dev)
Moore, Erice935d5d2006-03-14 09:18:18 -0700769{
770 if (dev->driver) {
771 if (dev->parent) /* Needed for USB */
772 down(&dev->parent->sem);
773 device_release_driver(dev);
774 if (dev->parent)
775 up(&dev->parent->sem);
776 }
Andrew Mortonf86db392006-08-14 22:43:20 -0700777 return bus_rescan_devices_helper(dev, NULL);
Moore, Erice935d5d2006-03-14 09:18:18 -0700778}
779EXPORT_SYMBOL_GPL(device_reprobe);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800782 * find_bus - locate bus by name.
783 * @name: name of bus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800785 * Call kset_find_obj() to iterate over list of buses to
786 * find a bus by name. Return bus if found.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800788 * Note that kset_find_obj increments bus' reference count.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 */
Adrian Bunk7e4ef082006-06-26 22:26:56 +0200790#if 0
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800791struct bus_type *find_bus(char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800793 struct kobject *k = kset_find_obj(bus_kset, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 return k ? to_bus(k) : NULL;
795}
Adrian Bunk7e4ef082006-06-26 22:26:56 +0200796#endif /* 0 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797
798
799/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800800 * bus_add_attrs - Add default attributes for this bus.
801 * @bus: Bus that has just been registered.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802 */
803
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800804static int bus_add_attrs(struct bus_type *bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805{
806 int error = 0;
807 int i;
808
809 if (bus->bus_attrs) {
810 for (i = 0; attr_name(bus->bus_attrs[i]); i++) {
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800811 error = bus_create_file(bus, &bus->bus_attrs[i]);
Cornelia Huckdc0afa82007-07-09 11:39:18 -0700812 if (error)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800813 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814 }
815 }
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800816done:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 return error;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800818err:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819 while (--i >= 0)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800820 bus_remove_file(bus, &bus->bus_attrs[i]);
821 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822}
823
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800824static void bus_remove_attrs(struct bus_type *bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825{
826 int i;
827
828 if (bus->bus_attrs) {
829 for (i = 0; attr_name(bus->bus_attrs[i]); i++)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800830 bus_remove_file(bus, &bus->bus_attrs[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 }
832}
833
James Bottomley34bb61f2005-09-06 16:56:51 -0700834static void klist_devices_get(struct klist_node *n)
835{
836 struct device *dev = container_of(n, struct device, knode_bus);
837
838 get_device(dev);
839}
840
841static void klist_devices_put(struct klist_node *n)
842{
843 struct device *dev = container_of(n, struct device, knode_bus);
844
845 put_device(dev);
846}
847
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200848static ssize_t bus_uevent_store(struct bus_type *bus,
849 const char *buf, size_t count)
850{
851 enum kobject_action action;
852
853 if (kobject_action_type(buf, count, &action) == 0)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700854 kobject_uevent(&bus->p->subsys.kobj, action);
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200855 return count;
856}
857static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store);
858
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800860 * bus_register - register a bus with the system.
861 * @bus: bus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800863 * Once we have that, we registered the bus with the kobject
864 * infrastructure, then register the children subsystems it has:
865 * the devices and drivers that belong to the bus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800867int bus_register(struct bus_type *bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868{
869 int retval;
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700870 struct bus_type_private *priv;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700872 priv = kzalloc(sizeof(struct bus_type_private), GFP_KERNEL);
873 if (!priv)
874 return -ENOMEM;
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000875
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700876 priv->bus = bus;
877 bus->p = priv;
878
879 BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);
880
881 retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 if (retval)
883 goto out;
884
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700885 priv->subsys.kobj.kset = bus_kset;
886 priv->subsys.kobj.ktype = &bus_ktype;
887 priv->drivers_autoprobe = 1;
Greg Kroah-Hartmand6b05b82007-09-12 15:06:57 -0700888
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700889 retval = kset_register(&priv->subsys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890 if (retval)
891 goto out;
892
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200893 retval = bus_create_file(bus, &bus_attr_uevent);
894 if (retval)
895 goto bus_uevent_fail;
896
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700897 priv->devices_kset = kset_create_and_add("devices", NULL,
898 &priv->subsys.kobj);
899 if (!priv->devices_kset) {
Greg Kroah-Hartman3d899592007-11-01 13:31:26 -0700900 retval = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901 goto bus_devices_fail;
Greg Kroah-Hartman3d899592007-11-01 13:31:26 -0700902 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700904 priv->drivers_kset = kset_create_and_add("drivers", NULL,
905 &priv->subsys.kobj);
906 if (!priv->drivers_kset) {
Greg Kroah-Hartman6dcec252007-11-01 13:31:26 -0700907 retval = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 goto bus_drivers_fail;
Greg Kroah-Hartman6dcec252007-11-01 13:31:26 -0700909 }
mochel@digitalimplant.org465c7a32005-03-21 11:49:14 -0800910
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700911 klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put);
912 klist_init(&priv->klist_drivers, NULL, NULL);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100913
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100914 retval = add_probe_files(bus);
915 if (retval)
916 goto bus_probe_files_fail;
917
Cornelia Huck1bb68812006-09-22 11:37:04 +0200918 retval = bus_add_attrs(bus);
919 if (retval)
920 goto bus_attrs_fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800922 pr_debug("bus: '%s': registered\n", bus->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923 return 0;
924
Cornelia Huck1bb68812006-09-22 11:37:04 +0200925bus_attrs_fail:
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100926 remove_probe_files(bus);
927bus_probe_files_fail:
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700928 kset_unregister(bus->p->drivers_kset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929bus_drivers_fail:
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700930 kset_unregister(bus->p->devices_kset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931bus_devices_fail:
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200932 bus_remove_file(bus, &bus_attr_uevent);
933bus_uevent_fail:
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700934 kset_unregister(&bus->p->subsys);
935 kfree(bus->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936out:
937 return retval;
938}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800939EXPORT_SYMBOL_GPL(bus_register);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800942 * bus_unregister - remove a bus from the system
943 * @bus: bus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800945 * Unregister the child subsystems and the bus itself.
946 * Finally, we call bus_put() to release the refcount
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800948void bus_unregister(struct bus_type *bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949{
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800950 pr_debug("bus: '%s': unregistering\n", bus->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700951 bus_remove_attrs(bus);
Kay Sieversb8c5cec2007-02-16 17:33:36 +0100952 remove_probe_files(bus);
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700953 kset_unregister(bus->p->drivers_kset);
954 kset_unregister(bus->p->devices_kset);
Kay Sievers7ac1cf42007-08-12 20:43:55 +0200955 bus_remove_file(bus, &bus_attr_uevent);
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700956 kset_unregister(&bus->p->subsys);
957 kfree(bus->p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800959EXPORT_SYMBOL_GPL(bus_unregister);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000961int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb)
962{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700963 return blocking_notifier_chain_register(&bus->p->bus_notifier, nb);
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000964}
965EXPORT_SYMBOL_GPL(bus_register_notifier);
966
967int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb)
968{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700969 return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb);
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000970}
971EXPORT_SYMBOL_GPL(bus_unregister_notifier);
972
Greg Kroah-Hartman0fed80f2007-11-01 19:41:16 -0700973struct kset *bus_get_kset(struct bus_type *bus)
974{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700975 return &bus->p->subsys;
Greg Kroah-Hartman0fed80f2007-11-01 19:41:16 -0700976}
977EXPORT_SYMBOL_GPL(bus_get_kset);
978
Greg Kroah-Hartmanb2490722007-11-01 19:41:16 -0700979struct klist *bus_get_device_klist(struct bus_type *bus)
980{
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700981 return &bus->p->klist_devices;
Greg Kroah-Hartmanb2490722007-11-01 19:41:16 -0700982}
983EXPORT_SYMBOL_GPL(bus_get_device_klist);
984
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985int __init buses_init(void)
986{
Greg Kroah-Hartman59a54832007-10-29 23:22:26 -0500987 bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL);
988 if (!bus_kset)
989 return -ENOMEM;
990 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991}