Commit | Line | Data |
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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); |
cda5e83f | 22 | return n ? container_of(n, struct device, knode_driver) : NULL; |
94e7b1c5 PM |
23 | } |
24 | ||
fae3cd00 | 25 | /** |
4a3ad20c GKH |
26 | * driver_for_each_device - Iterator for devices bound to a driver. |
27 | * @drv: Driver we're iterating. | |
28 | * @start: Device to begin with | |
29 | * @data: Data to pass to the callback. | |
30 | * @fn: Function to call for each device. | |
fae3cd00 | 31 | * |
4a3ad20c | 32 | * Iterate over the @drv's list of devices calling @fn for each one. |
fae3cd00 | 33 | */ |
4a3ad20c GKH |
34 | int driver_for_each_device(struct device_driver *drv, struct device *start, |
35 | void *data, int (*fn)(struct device *, void *)) | |
fae3cd00 | 36 | { |
94e7b1c5 | 37 | struct klist_iter i; |
4a3ad20c | 38 | struct device *dev; |
fae3cd00 PM |
39 | int error = 0; |
40 | ||
94e7b1c5 PM |
41 | if (!drv) |
42 | return -EINVAL; | |
43 | ||
e5dd1278 | 44 | klist_iter_init_node(&drv->p->klist_devices, &i, |
cda5e83f | 45 | start ? &start->knode_driver : NULL); |
94e7b1c5 | 46 | while ((dev = next_device(&i)) && !error) |
fae3cd00 | 47 | error = fn(dev, data); |
94e7b1c5 | 48 | klist_iter_exit(&i); |
fae3cd00 PM |
49 | return error; |
50 | } | |
126eddfb | 51 | EXPORT_SYMBOL_GPL(driver_for_each_device); |
fae3cd00 | 52 | |
0edb5860 CH |
53 | /** |
54 | * driver_find_device - device iterator for locating a particular device. | |
c41455fb | 55 | * @drv: The device's driver |
0edb5860 CH |
56 | * @start: Device to begin with |
57 | * @data: Data to pass to match function | |
58 | * @match: Callback function to check device | |
59 | * | |
60 | * This is similar to the driver_for_each_device() function above, but | |
61 | * it returns a reference to a device that is 'found' for later use, as | |
62 | * determined by the @match callback. | |
63 | * | |
64 | * The callback should return 0 if the device doesn't match and non-zero | |
65 | * if it does. If the callback returns non-zero, this function will | |
66 | * return to the caller and not iterate over any more devices. | |
67 | */ | |
4a3ad20c GKH |
68 | struct device *driver_find_device(struct device_driver *drv, |
69 | struct device *start, void *data, | |
70 | int (*match)(struct device *dev, void *data)) | |
0edb5860 CH |
71 | { |
72 | struct klist_iter i; | |
73 | struct device *dev; | |
74 | ||
75 | if (!drv) | |
76 | return NULL; | |
77 | ||
e5dd1278 | 78 | klist_iter_init_node(&drv->p->klist_devices, &i, |
cda5e83f | 79 | (start ? &start->knode_driver : NULL)); |
0edb5860 CH |
80 | while ((dev = next_device(&i))) |
81 | if (match(dev, data) && get_device(dev)) | |
82 | break; | |
83 | klist_iter_exit(&i); | |
84 | return dev; | |
85 | } | |
86 | EXPORT_SYMBOL_GPL(driver_find_device); | |
87 | ||
1da177e4 | 88 | /** |
4a3ad20c GKH |
89 | * driver_create_file - create sysfs file for driver. |
90 | * @drv: driver. | |
91 | * @attr: driver attribute descriptor. | |
1da177e4 | 92 | */ |
4a3ad20c GKH |
93 | int driver_create_file(struct device_driver *drv, |
94 | struct driver_attribute *attr) | |
1da177e4 LT |
95 | { |
96 | int error; | |
0c98b19f | 97 | if (drv) |
e5dd1278 | 98 | error = sysfs_create_file(&drv->p->kobj, &attr->attr); |
0c98b19f | 99 | else |
1da177e4 LT |
100 | error = -EINVAL; |
101 | return error; | |
102 | } | |
4a3ad20c | 103 | EXPORT_SYMBOL_GPL(driver_create_file); |
1da177e4 LT |
104 | |
105 | /** | |
4a3ad20c GKH |
106 | * driver_remove_file - remove sysfs file for driver. |
107 | * @drv: driver. | |
108 | * @attr: driver attribute descriptor. | |
1da177e4 | 109 | */ |
4a3ad20c GKH |
110 | void driver_remove_file(struct device_driver *drv, |
111 | struct driver_attribute *attr) | |
1da177e4 | 112 | { |
0c98b19f | 113 | if (drv) |
e5dd1278 | 114 | sysfs_remove_file(&drv->p->kobj, &attr->attr); |
1da177e4 | 115 | } |
4a3ad20c | 116 | EXPORT_SYMBOL_GPL(driver_remove_file); |
1da177e4 | 117 | |
cbe9c595 GKH |
118 | /** |
119 | * driver_add_kobj - add a kobject below the specified driver | |
7199677d RD |
120 | * @drv: requesting device driver |
121 | * @kobj: kobject to add below this driver | |
122 | * @fmt: format string that names the kobject | |
cbe9c595 GKH |
123 | * |
124 | * You really don't want to do this, this is only here due to one looney | |
125 | * iseries driver, go poke those developers if you are annoyed about | |
126 | * this... | |
127 | */ | |
128 | int driver_add_kobj(struct device_driver *drv, struct kobject *kobj, | |
129 | const char *fmt, ...) | |
130 | { | |
131 | va_list args; | |
132 | char *name; | |
d478376c | 133 | int ret; |
cbe9c595 GKH |
134 | |
135 | va_start(args, fmt); | |
136 | name = kvasprintf(GFP_KERNEL, fmt, args); | |
137 | va_end(args); | |
138 | ||
139 | if (!name) | |
140 | return -ENOMEM; | |
141 | ||
d478376c JJ |
142 | ret = kobject_add(kobj, &drv->p->kobj, "%s", name); |
143 | kfree(name); | |
144 | return ret; | |
cbe9c595 GKH |
145 | } |
146 | EXPORT_SYMBOL_GPL(driver_add_kobj); | |
147 | ||
1da177e4 | 148 | /** |
4a3ad20c GKH |
149 | * get_driver - increment driver reference count. |
150 | * @drv: driver. | |
1da177e4 | 151 | */ |
4a3ad20c | 152 | struct device_driver *get_driver(struct device_driver *drv) |
1da177e4 | 153 | { |
e5dd1278 GKH |
154 | if (drv) { |
155 | struct driver_private *priv; | |
156 | struct kobject *kobj; | |
157 | ||
158 | kobj = kobject_get(&drv->p->kobj); | |
159 | priv = to_driver(kobj); | |
160 | return priv->driver; | |
161 | } | |
162 | return NULL; | |
1da177e4 | 163 | } |
4a3ad20c | 164 | EXPORT_SYMBOL_GPL(get_driver); |
1da177e4 LT |
165 | |
166 | /** | |
4a3ad20c GKH |
167 | * put_driver - decrement driver's refcount. |
168 | * @drv: driver. | |
1da177e4 | 169 | */ |
4a3ad20c | 170 | void put_driver(struct device_driver *drv) |
1da177e4 | 171 | { |
e5dd1278 | 172 | kobject_put(&drv->p->kobj); |
1da177e4 | 173 | } |
4a3ad20c | 174 | EXPORT_SYMBOL_GPL(put_driver); |
1da177e4 | 175 | |
57c74534 CH |
176 | static int driver_add_groups(struct device_driver *drv, |
177 | struct attribute_group **groups) | |
178 | { | |
179 | int error = 0; | |
180 | int i; | |
181 | ||
182 | if (groups) { | |
183 | for (i = 0; groups[i]; i++) { | |
e5dd1278 | 184 | error = sysfs_create_group(&drv->p->kobj, groups[i]); |
57c74534 CH |
185 | if (error) { |
186 | while (--i >= 0) | |
e5dd1278 | 187 | sysfs_remove_group(&drv->p->kobj, |
57c74534 CH |
188 | groups[i]); |
189 | break; | |
190 | } | |
191 | } | |
192 | } | |
193 | return error; | |
194 | } | |
195 | ||
196 | static void driver_remove_groups(struct device_driver *drv, | |
197 | struct attribute_group **groups) | |
198 | { | |
199 | int i; | |
200 | ||
201 | if (groups) | |
202 | for (i = 0; groups[i]; i++) | |
e5dd1278 | 203 | sysfs_remove_group(&drv->p->kobj, groups[i]); |
57c74534 CH |
204 | } |
205 | ||
1da177e4 | 206 | /** |
4a3ad20c GKH |
207 | * driver_register - register driver with bus |
208 | * @drv: driver to register | |
1da177e4 | 209 | * |
4a3ad20c GKH |
210 | * We pass off most of the work to the bus_add_driver() call, |
211 | * since most of the things we have to do deal with the bus | |
212 | * structures. | |
1da177e4 | 213 | */ |
4a3ad20c | 214 | int driver_register(struct device_driver *drv) |
1da177e4 | 215 | { |
57c74534 | 216 | int ret; |
16dc42e0 | 217 | struct device_driver *other; |
57c74534 | 218 | |
594c8281 RK |
219 | if ((drv->bus->probe && drv->probe) || |
220 | (drv->bus->remove && drv->remove) || | |
4a3ad20c GKH |
221 | (drv->bus->shutdown && drv->shutdown)) |
222 | printk(KERN_WARNING "Driver '%s' needs updating - please use " | |
223 | "bus_type methods\n", drv->name); | |
16dc42e0 SS |
224 | |
225 | other = driver_find(drv->name, drv->bus); | |
226 | if (other) { | |
227 | put_driver(other); | |
228 | printk(KERN_ERR "Error: Driver '%s' is already registered, " | |
229 | "aborting...\n", drv->name); | |
230 | return -EEXIST; | |
231 | } | |
232 | ||
57c74534 CH |
233 | ret = bus_add_driver(drv); |
234 | if (ret) | |
235 | return ret; | |
236 | ret = driver_add_groups(drv, drv->groups); | |
237 | if (ret) | |
238 | bus_remove_driver(drv); | |
239 | return ret; | |
1da177e4 | 240 | } |
4a3ad20c | 241 | EXPORT_SYMBOL_GPL(driver_register); |
1da177e4 | 242 | |
1da177e4 | 243 | /** |
4a3ad20c GKH |
244 | * driver_unregister - remove driver from system. |
245 | * @drv: driver. | |
1da177e4 | 246 | * |
4a3ad20c | 247 | * Again, we pass off most of the work to the bus-level call. |
1da177e4 | 248 | */ |
4a3ad20c | 249 | void driver_unregister(struct device_driver *drv) |
1da177e4 | 250 | { |
57c74534 | 251 | driver_remove_groups(drv, drv->groups); |
1da177e4 | 252 | bus_remove_driver(drv); |
1da177e4 | 253 | } |
4a3ad20c | 254 | EXPORT_SYMBOL_GPL(driver_unregister); |
1da177e4 LT |
255 | |
256 | /** | |
4a3ad20c GKH |
257 | * driver_find - locate driver on a bus by its name. |
258 | * @name: name of the driver. | |
259 | * @bus: bus to scan for the driver. | |
1da177e4 | 260 | * |
4a3ad20c GKH |
261 | * Call kset_find_obj() to iterate over list of drivers on |
262 | * a bus to find driver by name. Return driver if found. | |
1da177e4 | 263 | * |
4a3ad20c | 264 | * Note that kset_find_obj increments driver's reference count. |
1da177e4 LT |
265 | */ |
266 | struct device_driver *driver_find(const char *name, struct bus_type *bus) | |
267 | { | |
c6f7e72a | 268 | struct kobject *k = kset_find_obj(bus->p->drivers_kset, name); |
e5dd1278 GKH |
269 | struct driver_private *priv; |
270 | ||
271 | if (k) { | |
272 | priv = to_driver(k); | |
273 | return priv->driver; | |
274 | } | |
1da177e4 LT |
275 | return NULL; |
276 | } | |
1da177e4 | 277 | EXPORT_SYMBOL_GPL(driver_find); |