Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * driver.c - centralized device driver management | |
3 | * | |
4 | * Copyright (c) 2002-3 Patrick Mochel | |
5 | * Copyright (c) 2002-3 Open Source Development Labs | |
e5dd1278 GKH |
6 | * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de> |
7 | * Copyright (c) 2007 Novell Inc. | |
1da177e4 LT |
8 | * |
9 | * This file is released under the GPLv2 | |
10 | * | |
11 | */ | |
12 | ||
1da177e4 LT |
13 | #include <linux/device.h> |
14 | #include <linux/module.h> | |
15 | #include <linux/errno.h> | |
16 | #include <linux/string.h> | |
17 | #include "base.h" | |
18 | ||
4a3ad20c | 19 | static struct device *next_device(struct klist_iter *i) |
94e7b1c5 | 20 | { |
4a3ad20c | 21 | struct klist_node *n = klist_next(i); |
8940b4f3 GKH |
22 | struct device *dev = NULL; |
23 | struct device_private *dev_prv; | |
24 | ||
25 | if (n) { | |
26 | dev_prv = to_device_private_driver(n); | |
27 | dev = dev_prv->device; | |
28 | } | |
29 | return dev; | |
94e7b1c5 | 30 | } |
31 | ||
fae3cd00 | 32 | /** |
4a3ad20c GKH |
33 | * driver_for_each_device - Iterator for devices bound to a driver. |
34 | * @drv: Driver we're iterating. | |
35 | * @start: Device to begin with | |
36 | * @data: Data to pass to the callback. | |
37 | * @fn: Function to call for each device. | |
fae3cd00 | 38 | * |
4a3ad20c | 39 | * Iterate over the @drv's list of devices calling @fn for each one. |
fae3cd00 | 40 | */ |
4a3ad20c GKH |
41 | int driver_for_each_device(struct device_driver *drv, struct device *start, |
42 | void *data, int (*fn)(struct device *, void *)) | |
fae3cd00 | 43 | { |
94e7b1c5 | 44 | struct klist_iter i; |
4a3ad20c | 45 | struct device *dev; |
fae3cd00 | 46 | int error = 0; |
47 | ||
94e7b1c5 | 48 | if (!drv) |
49 | return -EINVAL; | |
50 | ||
e5dd1278 | 51 | klist_iter_init_node(&drv->p->klist_devices, &i, |
8940b4f3 | 52 | start ? &start->p->knode_driver : NULL); |
94e7b1c5 | 53 | while ((dev = next_device(&i)) && !error) |
fae3cd00 | 54 | error = fn(dev, data); |
94e7b1c5 | 55 | klist_iter_exit(&i); |
fae3cd00 | 56 | return error; |
57 | } | |
126eddfb | 58 | EXPORT_SYMBOL_GPL(driver_for_each_device); |
fae3cd00 | 59 | |
0edb5860 CH |
60 | /** |
61 | * driver_find_device - device iterator for locating a particular device. | |
c41455fb | 62 | * @drv: The device's driver |
0edb5860 CH |
63 | * @start: Device to begin with |
64 | * @data: Data to pass to match function | |
65 | * @match: Callback function to check device | |
66 | * | |
67 | * This is similar to the driver_for_each_device() function above, but | |
68 | * it returns a reference to a device that is 'found' for later use, as | |
69 | * determined by the @match callback. | |
70 | * | |
71 | * The callback should return 0 if the device doesn't match and non-zero | |
72 | * if it does. If the callback returns non-zero, this function will | |
73 | * return to the caller and not iterate over any more devices. | |
74 | */ | |
4a3ad20c GKH |
75 | struct device *driver_find_device(struct device_driver *drv, |
76 | struct device *start, void *data, | |
77 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
78 | { |
79 | struct klist_iter i; | |
80 | struct device *dev; | |
81 | ||
82 | if (!drv) | |
83 | return NULL; | |
84 | ||
e5dd1278 | 85 | klist_iter_init_node(&drv->p->klist_devices, &i, |
8940b4f3 | 86 | (start ? &start->p->knode_driver : NULL)); |
0edb5860 CH |
87 | while ((dev = next_device(&i))) |
88 | if (match(dev, data) && get_device(dev)) | |
89 | break; | |
90 | klist_iter_exit(&i); | |
91 | return dev; | |
92 | } | |
93 | EXPORT_SYMBOL_GPL(driver_find_device); | |
94 | ||
1da177e4 | 95 | /** |
4a3ad20c GKH |
96 | * driver_create_file - create sysfs file for driver. |
97 | * @drv: driver. | |
98 | * @attr: driver attribute descriptor. | |
1da177e4 | 99 | */ |
4a3ad20c GKH |
100 | int driver_create_file(struct device_driver *drv, |
101 | struct driver_attribute *attr) | |
1da177e4 LT |
102 | { |
103 | int error; | |
0c98b19f | 104 | if (drv) |
e5dd1278 | 105 | error = sysfs_create_file(&drv->p->kobj, &attr->attr); |
0c98b19f | 106 | else |
1da177e4 LT |
107 | error = -EINVAL; |
108 | return error; | |
109 | } | |
4a3ad20c | 110 | EXPORT_SYMBOL_GPL(driver_create_file); |
1da177e4 LT |
111 | |
112 | /** | |
4a3ad20c GKH |
113 | * driver_remove_file - remove sysfs file for driver. |
114 | * @drv: driver. | |
115 | * @attr: driver attribute descriptor. | |
1da177e4 | 116 | */ |
4a3ad20c GKH |
117 | void driver_remove_file(struct device_driver *drv, |
118 | struct driver_attribute *attr) | |
1da177e4 | 119 | { |
0c98b19f | 120 | if (drv) |
e5dd1278 | 121 | sysfs_remove_file(&drv->p->kobj, &attr->attr); |
1da177e4 | 122 | } |
4a3ad20c | 123 | EXPORT_SYMBOL_GPL(driver_remove_file); |
1da177e4 | 124 | |
cbe9c595 GKH |
125 | /** |
126 | * driver_add_kobj - add a kobject below the specified driver | |
7199677d RD |
127 | * @drv: requesting device driver |
128 | * @kobj: kobject to add below this driver | |
129 | * @fmt: format string that names the kobject | |
cbe9c595 GKH |
130 | * |
131 | * You really don't want to do this, this is only here due to one looney | |
132 | * iseries driver, go poke those developers if you are annoyed about | |
133 | * this... | |
134 | */ | |
135 | int driver_add_kobj(struct device_driver *drv, struct kobject *kobj, | |
136 | const char *fmt, ...) | |
137 | { | |
138 | va_list args; | |
139 | char *name; | |
d478376c | 140 | int ret; |
cbe9c595 GKH |
141 | |
142 | va_start(args, fmt); | |
143 | name = kvasprintf(GFP_KERNEL, fmt, args); | |
144 | va_end(args); | |
145 | ||
146 | if (!name) | |
147 | return -ENOMEM; | |
148 | ||
d478376c JJ |
149 | ret = kobject_add(kobj, &drv->p->kobj, "%s", name); |
150 | kfree(name); | |
151 | return ret; | |
cbe9c595 GKH |
152 | } |
153 | EXPORT_SYMBOL_GPL(driver_add_kobj); | |
154 | ||
1da177e4 | 155 | /** |
4a3ad20c GKH |
156 | * get_driver - increment driver reference count. |
157 | * @drv: driver. | |
1da177e4 | 158 | */ |
4a3ad20c | 159 | struct device_driver *get_driver(struct device_driver *drv) |
1da177e4 | 160 | { |
e5dd1278 GKH |
161 | if (drv) { |
162 | struct driver_private *priv; | |
163 | struct kobject *kobj; | |
164 | ||
165 | kobj = kobject_get(&drv->p->kobj); | |
166 | priv = to_driver(kobj); | |
167 | return priv->driver; | |
168 | } | |
169 | return NULL; | |
1da177e4 | 170 | } |
4a3ad20c | 171 | EXPORT_SYMBOL_GPL(get_driver); |
1da177e4 LT |
172 | |
173 | /** | |
4a3ad20c GKH |
174 | * put_driver - decrement driver's refcount. |
175 | * @drv: driver. | |
1da177e4 | 176 | */ |
4a3ad20c | 177 | void put_driver(struct device_driver *drv) |
1da177e4 | 178 | { |
e5dd1278 | 179 | kobject_put(&drv->p->kobj); |
1da177e4 | 180 | } |
4a3ad20c | 181 | EXPORT_SYMBOL_GPL(put_driver); |
1da177e4 | 182 | |
57c74534 | 183 | static int driver_add_groups(struct device_driver *drv, |
a4dbd674 | 184 | const struct attribute_group **groups) |
57c74534 CH |
185 | { |
186 | int error = 0; | |
187 | int i; | |
188 | ||
189 | if (groups) { | |
190 | for (i = 0; groups[i]; i++) { | |
e5dd1278 | 191 | error = sysfs_create_group(&drv->p->kobj, groups[i]); |
57c74534 CH |
192 | if (error) { |
193 | while (--i >= 0) | |
e5dd1278 | 194 | sysfs_remove_group(&drv->p->kobj, |
57c74534 CH |
195 | groups[i]); |
196 | break; | |
197 | } | |
198 | } | |
199 | } | |
200 | return error; | |
201 | } | |
202 | ||
203 | static void driver_remove_groups(struct device_driver *drv, | |
a4dbd674 | 204 | const struct attribute_group **groups) |
57c74534 CH |
205 | { |
206 | int i; | |
207 | ||
208 | if (groups) | |
209 | for (i = 0; groups[i]; i++) | |
e5dd1278 | 210 | sysfs_remove_group(&drv->p->kobj, groups[i]); |
57c74534 CH |
211 | } |
212 | ||
1da177e4 | 213 | /** |
4a3ad20c GKH |
214 | * driver_register - register driver with bus |
215 | * @drv: driver to register | |
1da177e4 | 216 | * |
4a3ad20c GKH |
217 | * We pass off most of the work to the bus_add_driver() call, |
218 | * since most of the things we have to do deal with the bus | |
219 | * structures. | |
1da177e4 | 220 | */ |
4a3ad20c | 221 | int driver_register(struct device_driver *drv) |
1da177e4 | 222 | { |
57c74534 | 223 | int ret; |
16dc42e0 | 224 | struct device_driver *other; |
57c74534 | 225 | |
f48f3feb DY |
226 | BUG_ON(!drv->bus->p); |
227 | ||
594c8281 RK |
228 | if ((drv->bus->probe && drv->probe) || |
229 | (drv->bus->remove && drv->remove) || | |
4a3ad20c GKH |
230 | (drv->bus->shutdown && drv->shutdown)) |
231 | printk(KERN_WARNING "Driver '%s' needs updating - please use " | |
232 | "bus_type methods\n", drv->name); | |
16dc42e0 SS |
233 | |
234 | other = driver_find(drv->name, drv->bus); | |
235 | if (other) { | |
236 | put_driver(other); | |
237 | printk(KERN_ERR "Error: Driver '%s' is already registered, " | |
238 | "aborting...\n", drv->name); | |
239 | return -EEXIST; | |
240 | } | |
241 | ||
57c74534 CH |
242 | ret = bus_add_driver(drv); |
243 | if (ret) | |
244 | return ret; | |
245 | ret = driver_add_groups(drv, drv->groups); | |
246 | if (ret) | |
247 | bus_remove_driver(drv); | |
248 | return ret; | |
1da177e4 | 249 | } |
4a3ad20c | 250 | EXPORT_SYMBOL_GPL(driver_register); |
1da177e4 | 251 | |
1da177e4 | 252 | /** |
4a3ad20c GKH |
253 | * driver_unregister - remove driver from system. |
254 | * @drv: driver. | |
1da177e4 | 255 | * |
4a3ad20c | 256 | * Again, we pass off most of the work to the bus-level call. |
1da177e4 | 257 | */ |
4a3ad20c | 258 | void driver_unregister(struct device_driver *drv) |
1da177e4 | 259 | { |
5c8563d7 KS |
260 | if (!drv || !drv->p) { |
261 | WARN(1, "Unexpected driver unregister!\n"); | |
262 | return; | |
263 | } | |
57c74534 | 264 | driver_remove_groups(drv, drv->groups); |
1da177e4 | 265 | bus_remove_driver(drv); |
1da177e4 | 266 | } |
4a3ad20c | 267 | EXPORT_SYMBOL_GPL(driver_unregister); |
1da177e4 LT |
268 | |
269 | /** | |
4a3ad20c GKH |
270 | * driver_find - locate driver on a bus by its name. |
271 | * @name: name of the driver. | |
272 | * @bus: bus to scan for the driver. | |
1da177e4 | 273 | * |
4a3ad20c GKH |
274 | * Call kset_find_obj() to iterate over list of drivers on |
275 | * a bus to find driver by name. Return driver if found. | |
1da177e4 | 276 | * |
4a3ad20c | 277 | * Note that kset_find_obj increments driver's reference count. |
1da177e4 LT |
278 | */ |
279 | struct device_driver *driver_find(const char *name, struct bus_type *bus) | |
280 | { | |
c6f7e72a | 281 | struct kobject *k = kset_find_obj(bus->p->drivers_kset, name); |
e5dd1278 GKH |
282 | struct driver_private *priv; |
283 | ||
284 | if (k) { | |
285 | priv = to_driver(k); | |
286 | return priv->driver; | |
287 | } | |
1da177e4 LT |
288 | return NULL; |
289 | } | |
1da177e4 | 290 | EXPORT_SYMBOL_GPL(driver_find); |