Commit | Line | Data |
---|---|---|
989d42e8 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * driver.c - centralized device 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 | ||
4c002c97 | 11 | #include <linux/device/driver.h> |
1da177e4 LT |
12 | #include <linux/device.h> |
13 | #include <linux/module.h> | |
14 | #include <linux/errno.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
1da177e4 | 16 | #include <linux/string.h> |
63967685 | 17 | #include <linux/sysfs.h> |
1da177e4 LT |
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 | ||
7cd9c9bb GKH |
52 | klist_iter_init_node(&drv->p->klist_devices, &i, |
53 | start ? &start->p->knode_driver : NULL); | |
93ead7c9 | 54 | while (!error && (dev = next_device(&i))) |
7cd9c9bb GKH |
55 | error = fn(dev, data); |
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 | 76 | struct device *driver_find_device(struct device_driver *drv, |
92ce7e83 SP |
77 | struct device *start, const void *data, |
78 | int (*match)(struct device *dev, const void *data)) | |
0edb5860 CH |
79 | { |
80 | struct klist_iter i; | |
81 | struct device *dev; | |
82 | ||
094e47e9 | 83 | if (!drv || !drv->p) |
0edb5860 CH |
84 | return NULL; |
85 | ||
7cd9c9bb GKH |
86 | klist_iter_init_node(&drv->p->klist_devices, &i, |
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; | |
74642c6c | 105 | |
0c98b19f | 106 | if (drv) |
e5dd1278 | 107 | error = sysfs_create_file(&drv->p->kobj, &attr->attr); |
0c98b19f | 108 | else |
1da177e4 LT |
109 | error = -EINVAL; |
110 | return error; | |
111 | } | |
4a3ad20c | 112 | EXPORT_SYMBOL_GPL(driver_create_file); |
1da177e4 LT |
113 | |
114 | /** | |
4a3ad20c GKH |
115 | * driver_remove_file - remove sysfs file for driver. |
116 | * @drv: driver. | |
117 | * @attr: driver attribute descriptor. | |
1da177e4 | 118 | */ |
4a3ad20c | 119 | void driver_remove_file(struct device_driver *drv, |
099c2f21 | 120 | const struct driver_attribute *attr) |
1da177e4 | 121 | { |
0c98b19f | 122 | if (drv) |
e5dd1278 | 123 | sysfs_remove_file(&drv->p->kobj, &attr->attr); |
1da177e4 | 124 | } |
4a3ad20c | 125 | EXPORT_SYMBOL_GPL(driver_remove_file); |
1da177e4 | 126 | |
ed0617b5 GKH |
127 | int driver_add_groups(struct device_driver *drv, |
128 | const struct attribute_group **groups) | |
57c74534 | 129 | { |
3e9b2bae | 130 | return sysfs_create_groups(&drv->p->kobj, groups); |
57c74534 CH |
131 | } |
132 | ||
ed0617b5 GKH |
133 | void driver_remove_groups(struct device_driver *drv, |
134 | const struct attribute_group **groups) | |
57c74534 | 135 | { |
3e9b2bae | 136 | sysfs_remove_groups(&drv->p->kobj, groups); |
57c74534 CH |
137 | } |
138 | ||
1da177e4 | 139 | /** |
4a3ad20c GKH |
140 | * driver_register - register driver with bus |
141 | * @drv: driver to register | |
1da177e4 | 142 | * |
4a3ad20c GKH |
143 | * We pass off most of the work to the bus_add_driver() call, |
144 | * since most of the things we have to do deal with the bus | |
145 | * structures. | |
1da177e4 | 146 | */ |
4a3ad20c | 147 | int driver_register(struct device_driver *drv) |
1da177e4 | 148 | { |
57c74534 | 149 | int ret; |
16dc42e0 | 150 | struct device_driver *other; |
57c74534 | 151 | |
0dda2bb6 FS |
152 | if (!drv->bus->p) { |
153 | pr_err("Driver '%s' was unable to register with bus_type '%s' because the bus was not initialized.\n", | |
154 | drv->name, drv->bus->name); | |
155 | return -EINVAL; | |
156 | } | |
f48f3feb | 157 | |
594c8281 RK |
158 | if ((drv->bus->probe && drv->probe) || |
159 | (drv->bus->remove && drv->remove) || | |
4a3ad20c | 160 | (drv->bus->shutdown && drv->shutdown)) |
5962b8b2 | 161 | pr_warn("Driver '%s' needs updating - please use " |
4a3ad20c | 162 | "bus_type methods\n", drv->name); |
16dc42e0 SS |
163 | |
164 | other = driver_find(drv->name, drv->bus); | |
165 | if (other) { | |
5962b8b2 | 166 | pr_err("Error: Driver '%s' is already registered, " |
16dc42e0 | 167 | "aborting...\n", drv->name); |
39acbc12 | 168 | return -EBUSY; |
16dc42e0 SS |
169 | } |
170 | ||
57c74534 CH |
171 | ret = bus_add_driver(drv); |
172 | if (ret) | |
173 | return ret; | |
174 | ret = driver_add_groups(drv, drv->groups); | |
a14af325 | 175 | if (ret) { |
57c74534 | 176 | bus_remove_driver(drv); |
a14af325 SO |
177 | return ret; |
178 | } | |
5a7689fd SO |
179 | kobject_uevent(&drv->p->kobj, KOBJ_ADD); |
180 | ||
57c74534 | 181 | return ret; |
1da177e4 | 182 | } |
4a3ad20c | 183 | EXPORT_SYMBOL_GPL(driver_register); |
1da177e4 | 184 | |
1da177e4 | 185 | /** |
4a3ad20c GKH |
186 | * driver_unregister - remove driver from system. |
187 | * @drv: driver. | |
1da177e4 | 188 | * |
4a3ad20c | 189 | * Again, we pass off most of the work to the bus-level call. |
1da177e4 | 190 | */ |
4a3ad20c | 191 | void driver_unregister(struct device_driver *drv) |
1da177e4 | 192 | { |
5c8563d7 KS |
193 | if (!drv || !drv->p) { |
194 | WARN(1, "Unexpected driver unregister!\n"); | |
195 | return; | |
196 | } | |
57c74534 | 197 | driver_remove_groups(drv, drv->groups); |
1da177e4 | 198 | bus_remove_driver(drv); |
1da177e4 | 199 | } |
4a3ad20c | 200 | EXPORT_SYMBOL_GPL(driver_unregister); |
1da177e4 LT |
201 | |
202 | /** | |
4a3ad20c GKH |
203 | * driver_find - locate driver on a bus by its name. |
204 | * @name: name of the driver. | |
205 | * @bus: bus to scan for the driver. | |
1da177e4 | 206 | * |
4a3ad20c GKH |
207 | * Call kset_find_obj() to iterate over list of drivers on |
208 | * a bus to find driver by name. Return driver if found. | |
1da177e4 | 209 | * |
fde25a9b AS |
210 | * This routine provides no locking to prevent the driver it returns |
211 | * from being unregistered or unloaded while the caller is using it. | |
212 | * The caller is responsible for preventing this. | |
1da177e4 LT |
213 | */ |
214 | struct device_driver *driver_find(const char *name, struct bus_type *bus) | |
215 | { | |
c6f7e72a | 216 | struct kobject *k = kset_find_obj(bus->p->drivers_kset, name); |
e5dd1278 GKH |
217 | struct driver_private *priv; |
218 | ||
219 | if (k) { | |
fde25a9b AS |
220 | /* Drop reference added by kset_find_obj() */ |
221 | kobject_put(k); | |
e5dd1278 GKH |
222 | priv = to_driver(k); |
223 | return priv->driver; | |
224 | } | |
1da177e4 LT |
225 | return NULL; |
226 | } | |
1da177e4 | 227 | EXPORT_SYMBOL_GPL(driver_find); |