Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * bus.c - bus driver management |
| 3 | * |
| 4 | * Copyright (c) 2002-3 Patrick Mochel |
| 5 | * Copyright (c) 2002-3 Open Source Development Labs |
| 6 | * |
| 7 | * This file is released under the GPLv2 |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | #include <linux/config.h> |
| 12 | #include <linux/device.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/errno.h> |
| 15 | #include <linux/init.h> |
| 16 | #include <linux/string.h> |
| 17 | #include "base.h" |
| 18 | #include "power/power.h" |
| 19 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr) |
| 21 | #define to_bus(obj) container_of(obj, struct bus_type, subsys.kset.kobj) |
| 22 | |
| 23 | /* |
| 24 | * sysfs bindings for drivers |
| 25 | */ |
| 26 | |
| 27 | #define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr) |
| 28 | #define to_driver(obj) container_of(obj, struct device_driver, kobj) |
| 29 | |
| 30 | |
| 31 | static ssize_t |
| 32 | drv_attr_show(struct kobject * kobj, struct attribute * attr, char * buf) |
| 33 | { |
| 34 | struct driver_attribute * drv_attr = to_drv_attr(attr); |
| 35 | struct device_driver * drv = to_driver(kobj); |
Dmitry Torokhov | 4a0c20b | 2005-04-29 01:23:47 -0500 | [diff] [blame] | 36 | ssize_t ret = -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
| 38 | if (drv_attr->show) |
| 39 | ret = drv_attr->show(drv, buf); |
| 40 | return ret; |
| 41 | } |
| 42 | |
| 43 | static ssize_t |
| 44 | drv_attr_store(struct kobject * kobj, struct attribute * attr, |
| 45 | const char * buf, size_t count) |
| 46 | { |
| 47 | struct driver_attribute * drv_attr = to_drv_attr(attr); |
| 48 | struct device_driver * drv = to_driver(kobj); |
Dmitry Torokhov | 4a0c20b | 2005-04-29 01:23:47 -0500 | [diff] [blame] | 49 | ssize_t ret = -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | |
| 51 | if (drv_attr->store) |
| 52 | ret = drv_attr->store(drv, buf, count); |
| 53 | return ret; |
| 54 | } |
| 55 | |
| 56 | static struct sysfs_ops driver_sysfs_ops = { |
| 57 | .show = drv_attr_show, |
| 58 | .store = drv_attr_store, |
| 59 | }; |
| 60 | |
| 61 | |
| 62 | static void driver_release(struct kobject * kobj) |
| 63 | { |
| 64 | struct device_driver * drv = to_driver(kobj); |
| 65 | complete(&drv->unloaded); |
| 66 | } |
| 67 | |
| 68 | static struct kobj_type ktype_driver = { |
| 69 | .sysfs_ops = &driver_sysfs_ops, |
| 70 | .release = driver_release, |
| 71 | }; |
| 72 | |
| 73 | |
| 74 | /* |
| 75 | * sysfs bindings for buses |
| 76 | */ |
| 77 | |
| 78 | |
| 79 | static ssize_t |
| 80 | bus_attr_show(struct kobject * kobj, struct attribute * attr, char * buf) |
| 81 | { |
| 82 | struct bus_attribute * bus_attr = to_bus_attr(attr); |
| 83 | struct bus_type * bus = to_bus(kobj); |
| 84 | ssize_t ret = 0; |
| 85 | |
| 86 | if (bus_attr->show) |
| 87 | ret = bus_attr->show(bus, buf); |
| 88 | return ret; |
| 89 | } |
| 90 | |
| 91 | static ssize_t |
| 92 | bus_attr_store(struct kobject * kobj, struct attribute * attr, |
| 93 | const char * buf, size_t count) |
| 94 | { |
| 95 | struct bus_attribute * bus_attr = to_bus_attr(attr); |
| 96 | struct bus_type * bus = to_bus(kobj); |
| 97 | ssize_t ret = 0; |
| 98 | |
| 99 | if (bus_attr->store) |
| 100 | ret = bus_attr->store(bus, buf, count); |
| 101 | return ret; |
| 102 | } |
| 103 | |
| 104 | static struct sysfs_ops bus_sysfs_ops = { |
| 105 | .show = bus_attr_show, |
| 106 | .store = bus_attr_store, |
| 107 | }; |
| 108 | |
| 109 | int bus_create_file(struct bus_type * bus, struct bus_attribute * attr) |
| 110 | { |
| 111 | int error; |
| 112 | if (get_bus(bus)) { |
| 113 | error = sysfs_create_file(&bus->subsys.kset.kobj, &attr->attr); |
| 114 | put_bus(bus); |
| 115 | } else |
| 116 | error = -EINVAL; |
| 117 | return error; |
| 118 | } |
| 119 | |
| 120 | void bus_remove_file(struct bus_type * bus, struct bus_attribute * attr) |
| 121 | { |
| 122 | if (get_bus(bus)) { |
| 123 | sysfs_remove_file(&bus->subsys.kset.kobj, &attr->attr); |
| 124 | put_bus(bus); |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | static struct kobj_type ktype_bus = { |
| 129 | .sysfs_ops = &bus_sysfs_ops, |
| 130 | |
| 131 | }; |
| 132 | |
| 133 | decl_subsys(bus, &ktype_bus, NULL); |
| 134 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | |
Alan Stern | 2b08c8d | 2005-11-23 15:43:50 -0800 | [diff] [blame] | 136 | /* Manually detach a device from its associated driver. */ |
Greg Kroah-Hartman | 151ef38 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 137 | static int driver_helper(struct device *dev, void *data) |
| 138 | { |
| 139 | const char *name = data; |
| 140 | |
| 141 | if (strcmp(name, dev->bus_id) == 0) |
| 142 | return 1; |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | static ssize_t driver_unbind(struct device_driver *drv, |
| 147 | const char *buf, size_t count) |
| 148 | { |
| 149 | struct bus_type *bus = get_bus(drv->bus); |
| 150 | struct device *dev; |
| 151 | int err = -ENODEV; |
| 152 | |
| 153 | dev = bus_find_device(bus, NULL, (void *)buf, driver_helper); |
Alan Stern | 2b08c8d | 2005-11-23 15:43:50 -0800 | [diff] [blame] | 154 | if (dev && dev->driver == drv) { |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 155 | if (dev->parent) /* Needed for USB */ |
| 156 | down(&dev->parent->sem); |
Greg Kroah-Hartman | 151ef38 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 157 | device_release_driver(dev); |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 158 | if (dev->parent) |
| 159 | up(&dev->parent->sem); |
Greg Kroah-Hartman | 151ef38 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 160 | err = count; |
| 161 | } |
Alan Stern | 2b08c8d | 2005-11-23 15:43:50 -0800 | [diff] [blame] | 162 | put_device(dev); |
| 163 | put_bus(bus); |
| 164 | return err; |
Greg Kroah-Hartman | 151ef38 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 165 | } |
| 166 | static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind); |
| 167 | |
Greg Kroah-Hartman | afdce75 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 168 | /* |
| 169 | * Manually attach a device to a driver. |
| 170 | * Note: the driver must want to bind to the device, |
| 171 | * it is not possible to override the driver's id table. |
| 172 | */ |
| 173 | static ssize_t driver_bind(struct device_driver *drv, |
| 174 | const char *buf, size_t count) |
| 175 | { |
| 176 | struct bus_type *bus = get_bus(drv->bus); |
| 177 | struct device *dev; |
| 178 | int err = -ENODEV; |
| 179 | |
| 180 | dev = bus_find_device(bus, NULL, (void *)buf, driver_helper); |
Alan Stern | 2b08c8d | 2005-11-23 15:43:50 -0800 | [diff] [blame] | 181 | if (dev && dev->driver == NULL) { |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 182 | if (dev->parent) /* Needed for USB */ |
| 183 | down(&dev->parent->sem); |
Greg Kroah-Hartman | afdce75 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 184 | down(&dev->sem); |
| 185 | err = driver_probe_device(drv, dev); |
| 186 | up(&dev->sem); |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 187 | if (dev->parent) |
| 188 | up(&dev->parent->sem); |
Greg Kroah-Hartman | afdce75 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 189 | } |
Alan Stern | 2b08c8d | 2005-11-23 15:43:50 -0800 | [diff] [blame] | 190 | put_device(dev); |
| 191 | put_bus(bus); |
| 192 | return err; |
Greg Kroah-Hartman | afdce75 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 193 | } |
| 194 | static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); |
| 195 | |
Greg Kroah-Hartman | 151ef38 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 196 | |
mochel@digitalimplant.org | 465c7a3 | 2005-03-21 11:49:14 -0800 | [diff] [blame] | 197 | static struct device * next_device(struct klist_iter * i) |
| 198 | { |
| 199 | struct klist_node * n = klist_next(i); |
| 200 | return n ? container_of(n, struct device, knode_bus) : NULL; |
| 201 | } |
| 202 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | /** |
| 204 | * bus_for_each_dev - device iterator. |
| 205 | * @bus: bus type. |
| 206 | * @start: device to start iterating from. |
| 207 | * @data: data for the callback. |
| 208 | * @fn: function to be called for each device. |
| 209 | * |
| 210 | * Iterate over @bus's list of devices, and call @fn for each, |
| 211 | * passing it @data. If @start is not NULL, we use that device to |
| 212 | * begin iterating from. |
| 213 | * |
| 214 | * We check the return of @fn each time. If it returns anything |
| 215 | * other than 0, we break out and return that value. |
| 216 | * |
| 217 | * NOTE: The device that returns a non-zero value is not retained |
| 218 | * in any way, nor is its refcount incremented. If the caller needs |
| 219 | * to retain this data, it should do, and increment the reference |
| 220 | * count in the supplied callback. |
| 221 | */ |
| 222 | |
| 223 | int bus_for_each_dev(struct bus_type * bus, struct device * start, |
| 224 | void * data, int (*fn)(struct device *, void *)) |
| 225 | { |
mochel@digitalimplant.org | 465c7a3 | 2005-03-21 11:49:14 -0800 | [diff] [blame] | 226 | struct klist_iter i; |
| 227 | struct device * dev; |
| 228 | int error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | |
mochel@digitalimplant.org | 465c7a3 | 2005-03-21 11:49:14 -0800 | [diff] [blame] | 230 | if (!bus) |
| 231 | return -EINVAL; |
| 232 | |
| 233 | klist_iter_init_node(&bus->klist_devices, &i, |
| 234 | (start ? &start->knode_bus : NULL)); |
| 235 | while ((dev = next_device(&i)) && !error) |
| 236 | error = fn(dev, data); |
| 237 | klist_iter_exit(&i); |
| 238 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | } |
| 240 | |
Cornelia Huck | 0edb586 | 2005-06-22 16:59:51 +0200 | [diff] [blame] | 241 | /** |
| 242 | * bus_find_device - device iterator for locating a particular device. |
| 243 | * @bus: bus type |
| 244 | * @start: Device to begin with |
| 245 | * @data: Data to pass to match function |
| 246 | * @match: Callback function to check device |
| 247 | * |
| 248 | * This is similar to the bus_for_each_dev() function above, but it |
| 249 | * returns a reference to a device that is 'found' for later use, as |
| 250 | * determined by the @match callback. |
| 251 | * |
| 252 | * The callback should return 0 if the device doesn't match and non-zero |
| 253 | * if it does. If the callback returns non-zero, this function will |
| 254 | * return to the caller and not iterate over any more devices. |
| 255 | */ |
| 256 | struct device * bus_find_device(struct bus_type *bus, |
| 257 | struct device *start, void *data, |
| 258 | int (*match)(struct device *, void *)) |
| 259 | { |
| 260 | struct klist_iter i; |
| 261 | struct device *dev; |
| 262 | |
| 263 | if (!bus) |
| 264 | return NULL; |
| 265 | |
| 266 | klist_iter_init_node(&bus->klist_devices, &i, |
| 267 | (start ? &start->knode_bus : NULL)); |
| 268 | while ((dev = next_device(&i))) |
| 269 | if (match(dev, data) && get_device(dev)) |
| 270 | break; |
| 271 | klist_iter_exit(&i); |
| 272 | return dev; |
| 273 | } |
mochel@digitalimplant.org | 38fdac3 | 2005-03-21 12:00:18 -0800 | [diff] [blame] | 274 | |
| 275 | |
| 276 | static struct device_driver * next_driver(struct klist_iter * i) |
| 277 | { |
| 278 | struct klist_node * n = klist_next(i); |
| 279 | return n ? container_of(n, struct device_driver, knode_bus) : NULL; |
| 280 | } |
| 281 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | /** |
| 283 | * bus_for_each_drv - driver iterator |
| 284 | * @bus: bus we're dealing with. |
| 285 | * @start: driver to start iterating on. |
| 286 | * @data: data to pass to the callback. |
| 287 | * @fn: function to call for each driver. |
| 288 | * |
| 289 | * This is nearly identical to the device iterator above. |
| 290 | * We iterate over each driver that belongs to @bus, and call |
| 291 | * @fn for each. If @fn returns anything but 0, we break out |
| 292 | * and return it. If @start is not NULL, we use it as the head |
| 293 | * of the list. |
| 294 | * |
| 295 | * NOTE: we don't return the driver that returns a non-zero |
| 296 | * value, nor do we leave the reference count incremented for that |
| 297 | * driver. If the caller needs to know that info, it must set it |
| 298 | * in the callback. It must also be sure to increment the refcount |
| 299 | * so it doesn't disappear before returning to the caller. |
| 300 | */ |
| 301 | |
| 302 | int bus_for_each_drv(struct bus_type * bus, struct device_driver * start, |
| 303 | void * data, int (*fn)(struct device_driver *, void *)) |
| 304 | { |
mochel@digitalimplant.org | 38fdac3 | 2005-03-21 12:00:18 -0800 | [diff] [blame] | 305 | struct klist_iter i; |
| 306 | struct device_driver * drv; |
| 307 | int error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 308 | |
mochel@digitalimplant.org | 38fdac3 | 2005-03-21 12:00:18 -0800 | [diff] [blame] | 309 | if (!bus) |
| 310 | return -EINVAL; |
| 311 | |
| 312 | klist_iter_init_node(&bus->klist_drivers, &i, |
| 313 | start ? &start->knode_bus : NULL); |
| 314 | while ((drv = next_driver(&i)) && !error) |
| 315 | error = fn(drv, data); |
| 316 | klist_iter_exit(&i); |
| 317 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | } |
| 319 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | static int device_add_attrs(struct bus_type * bus, struct device * dev) |
| 321 | { |
| 322 | int error = 0; |
| 323 | int i; |
| 324 | |
| 325 | if (bus->dev_attrs) { |
| 326 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) { |
| 327 | error = device_create_file(dev,&bus->dev_attrs[i]); |
| 328 | if (error) |
| 329 | goto Err; |
| 330 | } |
| 331 | } |
| 332 | Done: |
| 333 | return error; |
| 334 | Err: |
| 335 | while (--i >= 0) |
| 336 | device_remove_file(dev,&bus->dev_attrs[i]); |
| 337 | goto Done; |
| 338 | } |
| 339 | |
| 340 | |
| 341 | static void device_remove_attrs(struct bus_type * bus, struct device * dev) |
| 342 | { |
| 343 | int i; |
| 344 | |
| 345 | if (bus->dev_attrs) { |
| 346 | for (i = 0; attr_name(bus->dev_attrs[i]); i++) |
| 347 | device_remove_file(dev,&bus->dev_attrs[i]); |
| 348 | } |
| 349 | } |
| 350 | |
| 351 | |
| 352 | /** |
| 353 | * bus_add_device - add device to bus |
| 354 | * @dev: device being added |
| 355 | * |
| 356 | * - Add the device to its bus's list of devices. |
| 357 | * - Try to attach to driver. |
| 358 | * - Create link to device's physical location. |
| 359 | */ |
| 360 | int bus_add_device(struct device * dev) |
| 361 | { |
| 362 | struct bus_type * bus = get_bus(dev->bus); |
| 363 | int error = 0; |
| 364 | |
| 365 | if (bus) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 366 | pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id); |
Greg Kroah-Hartman | d377e85 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 367 | device_attach(dev); |
James Bottomley | d856f1e3 | 2005-08-19 09:14:01 -0400 | [diff] [blame] | 368 | klist_add_tail(&dev->knode_bus, &bus->klist_devices); |
Greg Kroah-Hartman | d377e85 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 369 | error = device_add_attrs(bus, dev); |
Hannes Reinecke | ca2b94b | 2005-05-18 10:42:23 +0200 | [diff] [blame] | 370 | if (!error) { |
| 371 | sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id); |
| 372 | sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus"); |
| 373 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | } |
| 375 | return error; |
| 376 | } |
| 377 | |
| 378 | /** |
| 379 | * bus_remove_device - remove device from bus |
| 380 | * @dev: device to be removed |
| 381 | * |
| 382 | * - Remove symlink from bus's directory. |
| 383 | * - Delete device from bus's list. |
| 384 | * - Detach from its driver. |
| 385 | * - Drop reference taken in bus_add_device(). |
| 386 | */ |
| 387 | void bus_remove_device(struct device * dev) |
| 388 | { |
| 389 | if (dev->bus) { |
| 390 | sysfs_remove_link(&dev->kobj, "bus"); |
| 391 | sysfs_remove_link(&dev->bus->devices.kobj, dev->bus_id); |
| 392 | device_remove_attrs(dev->bus, dev); |
mochel@digitalimplant.org | 465c7a3 | 2005-03-21 11:49:14 -0800 | [diff] [blame] | 393 | klist_remove(&dev->knode_bus); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | pr_debug("bus %s: remove device %s\n", dev->bus->name, dev->bus_id); |
| 395 | device_release_driver(dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | put_bus(dev->bus); |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | static int driver_add_attrs(struct bus_type * bus, struct device_driver * drv) |
| 401 | { |
| 402 | int error = 0; |
| 403 | int i; |
| 404 | |
| 405 | if (bus->drv_attrs) { |
| 406 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) { |
| 407 | error = driver_create_file(drv, &bus->drv_attrs[i]); |
| 408 | if (error) |
| 409 | goto Err; |
| 410 | } |
| 411 | } |
| 412 | Done: |
| 413 | return error; |
| 414 | Err: |
| 415 | while (--i >= 0) |
| 416 | driver_remove_file(drv, &bus->drv_attrs[i]); |
| 417 | goto Done; |
| 418 | } |
| 419 | |
| 420 | |
| 421 | static void driver_remove_attrs(struct bus_type * bus, struct device_driver * drv) |
| 422 | { |
| 423 | int i; |
| 424 | |
| 425 | if (bus->drv_attrs) { |
| 426 | for (i = 0; attr_name(bus->drv_attrs[i]); i++) |
| 427 | driver_remove_file(drv, &bus->drv_attrs[i]); |
| 428 | } |
| 429 | } |
| 430 | |
Greg Kroah-Hartman | 874c624 | 2005-12-13 15:17:34 -0800 | [diff] [blame] | 431 | #ifdef CONFIG_HOTPLUG |
| 432 | /* |
| 433 | * Thanks to drivers making their tables __devinit, we can't allow manual |
| 434 | * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. |
| 435 | */ |
| 436 | static void add_bind_files(struct device_driver *drv) |
| 437 | { |
| 438 | driver_create_file(drv, &driver_attr_unbind); |
| 439 | driver_create_file(drv, &driver_attr_bind); |
| 440 | } |
| 441 | |
| 442 | static void remove_bind_files(struct device_driver *drv) |
| 443 | { |
| 444 | driver_remove_file(drv, &driver_attr_bind); |
| 445 | driver_remove_file(drv, &driver_attr_unbind); |
| 446 | } |
| 447 | #else |
| 448 | static inline void add_bind_files(struct device_driver *drv) {} |
| 449 | static inline void remove_bind_files(struct device_driver *drv) {} |
| 450 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | |
| 452 | /** |
| 453 | * bus_add_driver - Add a driver to the bus. |
| 454 | * @drv: driver. |
| 455 | * |
| 456 | */ |
| 457 | int bus_add_driver(struct device_driver * drv) |
| 458 | { |
| 459 | struct bus_type * bus = get_bus(drv->bus); |
| 460 | int error = 0; |
| 461 | |
| 462 | if (bus) { |
| 463 | pr_debug("bus %s: add driver %s\n", bus->name, drv->name); |
| 464 | error = kobject_set_name(&drv->kobj, "%s", drv->name); |
| 465 | if (error) { |
| 466 | put_bus(bus); |
| 467 | return error; |
| 468 | } |
| 469 | drv->kobj.kset = &bus->drivers; |
| 470 | if ((error = kobject_register(&drv->kobj))) { |
| 471 | put_bus(bus); |
| 472 | return error; |
| 473 | } |
| 474 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | driver_attach(drv); |
James Bottomley | d856f1e3 | 2005-08-19 09:14:01 -0400 | [diff] [blame] | 476 | klist_add_tail(&drv->knode_bus, &bus->klist_drivers); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | module_add_driver(drv->owner, drv); |
| 478 | |
| 479 | driver_add_attrs(bus, drv); |
Greg Kroah-Hartman | 874c624 | 2005-12-13 15:17:34 -0800 | [diff] [blame] | 480 | add_bind_files(drv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 481 | } |
| 482 | return error; |
| 483 | } |
| 484 | |
| 485 | |
| 486 | /** |
| 487 | * bus_remove_driver - delete driver from bus's knowledge. |
| 488 | * @drv: driver. |
| 489 | * |
| 490 | * Detach the driver from the devices it controls, and remove |
| 491 | * it from its bus's list of drivers. Finally, we drop the reference |
| 492 | * to the bus we took in bus_add_driver(). |
| 493 | */ |
| 494 | |
| 495 | void bus_remove_driver(struct device_driver * drv) |
| 496 | { |
| 497 | if (drv->bus) { |
Greg Kroah-Hartman | 874c624 | 2005-12-13 15:17:34 -0800 | [diff] [blame] | 498 | remove_bind_files(drv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | driver_remove_attrs(drv->bus, drv); |
mochel@digitalimplant.org | 38fdac3 | 2005-03-21 12:00:18 -0800 | [diff] [blame] | 500 | klist_remove(&drv->knode_bus); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name); |
| 502 | driver_detach(drv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 503 | module_remove_driver(drv); |
| 504 | kobject_unregister(&drv->kobj); |
| 505 | put_bus(drv->bus); |
| 506 | } |
| 507 | } |
| 508 | |
| 509 | |
| 510 | /* Helper for bus_rescan_devices's iter */ |
| 511 | static int bus_rescan_devices_helper(struct device *dev, void *data) |
| 512 | { |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 513 | if (!dev->driver) { |
| 514 | if (dev->parent) /* Needed for USB */ |
| 515 | down(&dev->parent->sem); |
Greg Kroah-Hartman | 23d3d60 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 516 | device_attach(dev); |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 517 | if (dev->parent) |
| 518 | up(&dev->parent->sem); |
| 519 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | return 0; |
| 521 | } |
| 522 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | /** |
Greg Kroah-Hartman | 23d3d60 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 524 | * bus_rescan_devices - rescan devices on the bus for possible drivers |
| 525 | * @bus: the bus to scan. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | * |
Greg Kroah-Hartman | 23d3d60 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 527 | * This function will look for devices on the bus with no driver |
| 528 | * attached and rescan it against existing drivers to see if it matches |
| 529 | * any by calling device_attach() for the unbound devices. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 530 | */ |
Greg Kroah-Hartman | 23d3d60 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 531 | void bus_rescan_devices(struct bus_type * bus) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | { |
Greg Kroah-Hartman | 23d3d60 | 2005-06-22 16:09:05 -0700 | [diff] [blame] | 533 | bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 534 | } |
| 535 | |
| 536 | |
| 537 | struct bus_type * get_bus(struct bus_type * bus) |
| 538 | { |
| 539 | return bus ? container_of(subsys_get(&bus->subsys), struct bus_type, subsys) : NULL; |
| 540 | } |
| 541 | |
| 542 | void put_bus(struct bus_type * bus) |
| 543 | { |
| 544 | subsys_put(&bus->subsys); |
| 545 | } |
| 546 | |
| 547 | |
| 548 | /** |
| 549 | * find_bus - locate bus by name. |
| 550 | * @name: name of bus. |
| 551 | * |
| 552 | * Call kset_find_obj() to iterate over list of buses to |
| 553 | * find a bus by name. Return bus if found. |
| 554 | * |
| 555 | * Note that kset_find_obj increments bus' reference count. |
| 556 | */ |
| 557 | |
| 558 | struct bus_type * find_bus(char * name) |
| 559 | { |
| 560 | struct kobject * k = kset_find_obj(&bus_subsys.kset, name); |
| 561 | return k ? to_bus(k) : NULL; |
| 562 | } |
| 563 | |
| 564 | |
| 565 | /** |
| 566 | * bus_add_attrs - Add default attributes for this bus. |
| 567 | * @bus: Bus that has just been registered. |
| 568 | */ |
| 569 | |
| 570 | static int bus_add_attrs(struct bus_type * bus) |
| 571 | { |
| 572 | int error = 0; |
| 573 | int i; |
| 574 | |
| 575 | if (bus->bus_attrs) { |
| 576 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) { |
| 577 | if ((error = bus_create_file(bus,&bus->bus_attrs[i]))) |
| 578 | goto Err; |
| 579 | } |
| 580 | } |
| 581 | Done: |
| 582 | return error; |
| 583 | Err: |
| 584 | while (--i >= 0) |
| 585 | bus_remove_file(bus,&bus->bus_attrs[i]); |
| 586 | goto Done; |
| 587 | } |
| 588 | |
| 589 | static void bus_remove_attrs(struct bus_type * bus) |
| 590 | { |
| 591 | int i; |
| 592 | |
| 593 | if (bus->bus_attrs) { |
| 594 | for (i = 0; attr_name(bus->bus_attrs[i]); i++) |
| 595 | bus_remove_file(bus,&bus->bus_attrs[i]); |
| 596 | } |
| 597 | } |
| 598 | |
James Bottomley | 34bb61f | 2005-09-06 16:56:51 -0700 | [diff] [blame] | 599 | static void klist_devices_get(struct klist_node *n) |
| 600 | { |
| 601 | struct device *dev = container_of(n, struct device, knode_bus); |
| 602 | |
| 603 | get_device(dev); |
| 604 | } |
| 605 | |
| 606 | static void klist_devices_put(struct klist_node *n) |
| 607 | { |
| 608 | struct device *dev = container_of(n, struct device, knode_bus); |
| 609 | |
| 610 | put_device(dev); |
| 611 | } |
| 612 | |
| 613 | static void klist_drivers_get(struct klist_node *n) |
| 614 | { |
| 615 | struct device_driver *drv = container_of(n, struct device_driver, |
| 616 | knode_bus); |
| 617 | |
| 618 | get_driver(drv); |
| 619 | } |
| 620 | |
| 621 | static void klist_drivers_put(struct klist_node *n) |
| 622 | { |
| 623 | struct device_driver *drv = container_of(n, struct device_driver, |
| 624 | knode_bus); |
| 625 | |
| 626 | put_driver(drv); |
| 627 | } |
| 628 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | /** |
| 630 | * bus_register - register a bus with the system. |
| 631 | * @bus: bus. |
| 632 | * |
| 633 | * Once we have that, we registered the bus with the kobject |
| 634 | * infrastructure, then register the children subsystems it has: |
| 635 | * the devices and drivers that belong to the bus. |
| 636 | */ |
| 637 | int bus_register(struct bus_type * bus) |
| 638 | { |
| 639 | int retval; |
| 640 | |
| 641 | retval = kobject_set_name(&bus->subsys.kset.kobj, "%s", bus->name); |
| 642 | if (retval) |
| 643 | goto out; |
| 644 | |
| 645 | subsys_set_kset(bus, bus_subsys); |
| 646 | retval = subsystem_register(&bus->subsys); |
| 647 | if (retval) |
| 648 | goto out; |
| 649 | |
| 650 | kobject_set_name(&bus->devices.kobj, "devices"); |
| 651 | bus->devices.subsys = &bus->subsys; |
| 652 | retval = kset_register(&bus->devices); |
| 653 | if (retval) |
| 654 | goto bus_devices_fail; |
| 655 | |
| 656 | kobject_set_name(&bus->drivers.kobj, "drivers"); |
| 657 | bus->drivers.subsys = &bus->subsys; |
| 658 | bus->drivers.ktype = &ktype_driver; |
| 659 | retval = kset_register(&bus->drivers); |
| 660 | if (retval) |
| 661 | goto bus_drivers_fail; |
mochel@digitalimplant.org | 465c7a3 | 2005-03-21 11:49:14 -0800 | [diff] [blame] | 662 | |
James Bottomley | 34bb61f | 2005-09-06 16:56:51 -0700 | [diff] [blame] | 663 | klist_init(&bus->klist_devices, klist_devices_get, klist_devices_put); |
| 664 | klist_init(&bus->klist_drivers, klist_drivers_get, klist_drivers_put); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | bus_add_attrs(bus); |
| 666 | |
| 667 | pr_debug("bus type '%s' registered\n", bus->name); |
| 668 | return 0; |
| 669 | |
| 670 | bus_drivers_fail: |
| 671 | kset_unregister(&bus->devices); |
| 672 | bus_devices_fail: |
| 673 | subsystem_unregister(&bus->subsys); |
| 674 | out: |
| 675 | return retval; |
| 676 | } |
| 677 | |
| 678 | |
| 679 | /** |
| 680 | * bus_unregister - remove a bus from the system |
| 681 | * @bus: bus. |
| 682 | * |
| 683 | * Unregister the child subsystems and the bus itself. |
| 684 | * Finally, we call put_bus() to release the refcount |
| 685 | */ |
| 686 | void bus_unregister(struct bus_type * bus) |
| 687 | { |
| 688 | pr_debug("bus %s: unregistering\n", bus->name); |
| 689 | bus_remove_attrs(bus); |
| 690 | kset_unregister(&bus->drivers); |
| 691 | kset_unregister(&bus->devices); |
| 692 | subsystem_unregister(&bus->subsys); |
| 693 | } |
| 694 | |
| 695 | int __init buses_init(void) |
| 696 | { |
| 697 | return subsystem_register(&bus_subsys); |
| 698 | } |
| 699 | |
| 700 | |
| 701 | EXPORT_SYMBOL_GPL(bus_for_each_dev); |
Cornelia Huck | 0edb586 | 2005-06-22 16:59:51 +0200 | [diff] [blame] | 702 | EXPORT_SYMBOL_GPL(bus_find_device); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | EXPORT_SYMBOL_GPL(bus_for_each_drv); |
| 704 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | EXPORT_SYMBOL_GPL(bus_add_device); |
| 706 | EXPORT_SYMBOL_GPL(bus_remove_device); |
| 707 | EXPORT_SYMBOL_GPL(bus_register); |
| 708 | EXPORT_SYMBOL_GPL(bus_unregister); |
| 709 | EXPORT_SYMBOL_GPL(bus_rescan_devices); |
| 710 | EXPORT_SYMBOL_GPL(get_bus); |
| 711 | EXPORT_SYMBOL_GPL(put_bus); |
| 712 | EXPORT_SYMBOL_GPL(find_bus); |
| 713 | |
| 714 | EXPORT_SYMBOL_GPL(bus_create_file); |
| 715 | EXPORT_SYMBOL_GPL(bus_remove_file); |