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> | |
5a0e3ad6 | 16 | #include <linux/slab.h> |
1da177e4 LT |
17 | #include <linux/string.h> |
18 | #include "base.h" | |
19 | ||
4a3ad20c | 20 | static struct device *next_device(struct klist_iter *i) |
94e7b1c5 | 21 | { |
4a3ad20c | 22 | struct klist_node *n = klist_next(i); |
8940b4f3 GKH |
23 | struct device *dev = NULL; |
24 | struct device_private *dev_prv; | |
25 | ||
26 | if (n) { | |
27 | dev_prv = to_device_private_driver(n); | |
28 | dev = dev_prv->device; | |
29 | } | |
30 | return dev; | |
94e7b1c5 | 31 | } |
32 | ||
fae3cd00 | 33 | /** |
4a3ad20c GKH |
34 | * driver_for_each_device - Iterator for devices bound to a driver. |
35 | * @drv: Driver we're iterating. | |
36 | * @start: Device to begin with | |
37 | * @data: Data to pass to the callback. | |
38 | * @fn: Function to call for each device. | |
fae3cd00 | 39 | * |
4a3ad20c | 40 | * Iterate over the @drv's list of devices calling @fn for each one. |
fae3cd00 | 41 | */ |
4a3ad20c GKH |
42 | int driver_for_each_device(struct device_driver *drv, struct device *start, |
43 | void *data, int (*fn)(struct device *, void *)) | |
fae3cd00 | 44 | { |
94e7b1c5 | 45 | struct klist_iter i; |
4a3ad20c | 46 | struct device *dev; |
fae3cd00 | 47 | int error = 0; |
48 | ||
94e7b1c5 | 49 | if (!drv) |
50 | return -EINVAL; | |
51 | ||
e5dd1278 | 52 | klist_iter_init_node(&drv->p->klist_devices, &i, |
8940b4f3 | 53 | start ? &start->p->knode_driver : NULL); |
94e7b1c5 | 54 | while ((dev = next_device(&i)) && !error) |
fae3cd00 | 55 | error = fn(dev, data); |
94e7b1c5 | 56 | klist_iter_exit(&i); |
fae3cd00 | 57 | return error; |
58 | } | |
126eddfb | 59 | EXPORT_SYMBOL_GPL(driver_for_each_device); |
fae3cd00 | 60 | |
0edb5860 CH |
61 | /** |
62 | * driver_find_device - device iterator for locating a particular device. | |
c41455fb | 63 | * @drv: The device's driver |
0edb5860 CH |
64 | * @start: Device to begin with |
65 | * @data: Data to pass to match function | |
66 | * @match: Callback function to check device | |
67 | * | |
68 | * This is similar to the driver_for_each_device() function above, but | |
69 | * it returns a reference to a device that is 'found' for later use, as | |
70 | * determined by the @match callback. | |
71 | * | |
72 | * The callback should return 0 if the device doesn't match and non-zero | |
73 | * if it does. If the callback returns non-zero, this function will | |
74 | * return to the caller and not iterate over any more devices. | |
75 | */ | |
4a3ad20c GKH |
76 | struct device *driver_find_device(struct device_driver *drv, |
77 | struct device *start, void *data, | |
78 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
79 | { |
80 | struct klist_iter i; | |
81 | struct device *dev; | |
82 | ||
83 | if (!drv) | |
84 | return NULL; | |
85 | ||
e5dd1278 | 86 | klist_iter_init_node(&drv->p->klist_devices, &i, |
8940b4f3 | 87 | (start ? &start->p->knode_driver : NULL)); |
0edb5860 CH |
88 | while ((dev = next_device(&i))) |
89 | if (match(dev, data) && get_device(dev)) | |
90 | break; | |
91 | klist_iter_exit(&i); | |
92 | return dev; | |
93 | } | |
94 | EXPORT_SYMBOL_GPL(driver_find_device); | |
95 | ||
1da177e4 | 96 | /** |
4a3ad20c GKH |
97 | * driver_create_file - create sysfs file for driver. |
98 | * @drv: driver. | |
99 | * @attr: driver attribute descriptor. | |
1da177e4 | 100 | */ |
4a3ad20c | 101 | int driver_create_file(struct device_driver *drv, |
099c2f21 | 102 | const struct driver_attribute *attr) |
1da177e4 LT |
103 | { |
104 | int error; | |
0c98b19f | 105 | if (drv) |
e5dd1278 | 106 | error = sysfs_create_file(&drv->p->kobj, &attr->attr); |
0c98b19f | 107 | else |
1da177e4 LT |
108 | error = -EINVAL; |
109 | return error; | |
110 | } | |
4a3ad20c | 111 | EXPORT_SYMBOL_GPL(driver_create_file); |
1da177e4 LT |
112 | |
113 | /** | |
4a3ad20c GKH |
114 | * driver_remove_file - remove sysfs file for driver. |
115 | * @drv: driver. | |
116 | * @attr: driver attribute descriptor. | |
1da177e4 | 117 | */ |
4a3ad20c | 118 | void driver_remove_file(struct device_driver *drv, |
099c2f21 | 119 | const struct driver_attribute *attr) |
1da177e4 | 120 | { |
0c98b19f | 121 | if (drv) |
e5dd1278 | 122 | sysfs_remove_file(&drv->p->kobj, &attr->attr); |
1da177e4 | 123 | } |
4a3ad20c | 124 | EXPORT_SYMBOL_GPL(driver_remove_file); |
1da177e4 | 125 | |
cbe9c595 GKH |
126 | /** |
127 | * driver_add_kobj - add a kobject below the specified driver | |
7199677d RD |
128 | * @drv: requesting device driver |
129 | * @kobj: kobject to add below this driver | |
130 | * @fmt: format string that names the kobject | |
cbe9c595 GKH |
131 | * |
132 | * You really don't want to do this, this is only here due to one looney | |
133 | * iseries driver, go poke those developers if you are annoyed about | |
134 | * this... | |
135 | */ | |
136 | int driver_add_kobj(struct device_driver *drv, struct kobject *kobj, | |
137 | const char *fmt, ...) | |
138 | { | |
139 | va_list args; | |
140 | char *name; | |
d478376c | 141 | int ret; |
cbe9c595 GKH |
142 | |
143 | va_start(args, fmt); | |
144 | name = kvasprintf(GFP_KERNEL, fmt, args); | |
145 | va_end(args); | |
146 | ||
147 | if (!name) | |
148 | return -ENOMEM; | |
149 | ||
d478376c JJ |
150 | ret = kobject_add(kobj, &drv->p->kobj, "%s", name); |
151 | kfree(name); | |
152 | return ret; | |
cbe9c595 GKH |
153 | } |
154 | EXPORT_SYMBOL_GPL(driver_add_kobj); | |
155 | ||
1da177e4 | 156 | /** |
4a3ad20c GKH |
157 | * get_driver - increment driver reference count. |
158 | * @drv: driver. | |
1da177e4 | 159 | */ |
4a3ad20c | 160 | struct device_driver *get_driver(struct device_driver *drv) |
1da177e4 | 161 | { |
e5dd1278 GKH |
162 | if (drv) { |
163 | struct driver_private *priv; | |
164 | struct kobject *kobj; | |
165 | ||
166 | kobj = kobject_get(&drv->p->kobj); | |
167 | priv = to_driver(kobj); | |
168 | return priv->driver; | |
169 | } | |
170 | return NULL; | |
1da177e4 | 171 | } |
4a3ad20c | 172 | EXPORT_SYMBOL_GPL(get_driver); |
1da177e4 LT |
173 | |
174 | /** | |
4a3ad20c GKH |
175 | * put_driver - decrement driver's refcount. |
176 | * @drv: driver. | |
1da177e4 | 177 | */ |
4a3ad20c | 178 | void put_driver(struct device_driver *drv) |
1da177e4 | 179 | { |
e5dd1278 | 180 | kobject_put(&drv->p->kobj); |
1da177e4 | 181 | } |
4a3ad20c | 182 | EXPORT_SYMBOL_GPL(put_driver); |
1da177e4 | 183 | |
57c74534 | 184 | static int driver_add_groups(struct device_driver *drv, |
a4dbd674 | 185 | const struct attribute_group **groups) |
57c74534 CH |
186 | { |
187 | int error = 0; | |
188 | int i; | |
189 | ||
190 | if (groups) { | |
191 | for (i = 0; groups[i]; i++) { | |
e5dd1278 | 192 | error = sysfs_create_group(&drv->p->kobj, groups[i]); |
57c74534 CH |
193 | if (error) { |
194 | while (--i >= 0) | |
e5dd1278 | 195 | sysfs_remove_group(&drv->p->kobj, |
57c74534 CH |
196 | groups[i]); |
197 | break; | |
198 | } | |
199 | } | |
200 | } | |
201 | return error; | |
202 | } | |
203 | ||
204 | static void driver_remove_groups(struct device_driver *drv, | |
a4dbd674 | 205 | const struct attribute_group **groups) |
57c74534 CH |
206 | { |
207 | int i; | |
208 | ||
209 | if (groups) | |
210 | for (i = 0; groups[i]; i++) | |
e5dd1278 | 211 | sysfs_remove_group(&drv->p->kobj, groups[i]); |
57c74534 CH |
212 | } |
213 | ||
1da177e4 | 214 | /** |
4a3ad20c GKH |
215 | * driver_register - register driver with bus |
216 | * @drv: driver to register | |
1da177e4 | 217 | * |
4a3ad20c GKH |
218 | * We pass off most of the work to the bus_add_driver() call, |
219 | * since most of the things we have to do deal with the bus | |
220 | * structures. | |
1da177e4 | 221 | */ |
4a3ad20c | 222 | int driver_register(struct device_driver *drv) |
1da177e4 | 223 | { |
57c74534 | 224 | int ret; |
16dc42e0 | 225 | struct device_driver *other; |
57c74534 | 226 | |
f48f3feb DY |
227 | BUG_ON(!drv->bus->p); |
228 | ||
594c8281 RK |
229 | if ((drv->bus->probe && drv->probe) || |
230 | (drv->bus->remove && drv->remove) || | |
4a3ad20c GKH |
231 | (drv->bus->shutdown && drv->shutdown)) |
232 | printk(KERN_WARNING "Driver '%s' needs updating - please use " | |
233 | "bus_type methods\n", drv->name); | |
16dc42e0 SS |
234 | |
235 | other = driver_find(drv->name, drv->bus); | |
236 | if (other) { | |
237 | put_driver(other); | |
238 | printk(KERN_ERR "Error: Driver '%s' is already registered, " | |
239 | "aborting...\n", drv->name); | |
39acbc12 | 240 | return -EBUSY; |
16dc42e0 SS |
241 | } |
242 | ||
57c74534 CH |
243 | ret = bus_add_driver(drv); |
244 | if (ret) | |
245 | return ret; | |
246 | ret = driver_add_groups(drv, drv->groups); | |
247 | if (ret) | |
248 | bus_remove_driver(drv); | |
249 | return ret; | |
1da177e4 | 250 | } |
4a3ad20c | 251 | EXPORT_SYMBOL_GPL(driver_register); |
1da177e4 | 252 | |
1da177e4 | 253 | /** |
4a3ad20c GKH |
254 | * driver_unregister - remove driver from system. |
255 | * @drv: driver. | |
1da177e4 | 256 | * |
4a3ad20c | 257 | * Again, we pass off most of the work to the bus-level call. |
1da177e4 | 258 | */ |
4a3ad20c | 259 | void driver_unregister(struct device_driver *drv) |
1da177e4 | 260 | { |
5c8563d7 KS |
261 | if (!drv || !drv->p) { |
262 | WARN(1, "Unexpected driver unregister!\n"); | |
263 | return; | |
264 | } | |
57c74534 | 265 | driver_remove_groups(drv, drv->groups); |
1da177e4 | 266 | bus_remove_driver(drv); |
1da177e4 | 267 | } |
4a3ad20c | 268 | EXPORT_SYMBOL_GPL(driver_unregister); |
1da177e4 LT |
269 | |
270 | /** | |
4a3ad20c GKH |
271 | * driver_find - locate driver on a bus by its name. |
272 | * @name: name of the driver. | |
273 | * @bus: bus to scan for the driver. | |
1da177e4 | 274 | * |
4a3ad20c GKH |
275 | * Call kset_find_obj() to iterate over list of drivers on |
276 | * a bus to find driver by name. Return driver if found. | |
1da177e4 | 277 | * |
4a3ad20c | 278 | * Note that kset_find_obj increments driver's reference count. |
1da177e4 LT |
279 | */ |
280 | struct device_driver *driver_find(const char *name, struct bus_type *bus) | |
281 | { | |
c6f7e72a | 282 | struct kobject *k = kset_find_obj(bus->p->drivers_kset, name); |
e5dd1278 GKH |
283 | struct driver_private *priv; |
284 | ||
285 | if (k) { | |
286 | priv = to_driver(k); | |
287 | return priv->driver; | |
288 | } | |
1da177e4 LT |
289 | return NULL; |
290 | } | |
1da177e4 | 291 | EXPORT_SYMBOL_GPL(driver_find); |