4 * Driver utility functions for libsysfs
6 * Copyright (C) IBM Corp. 2003
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 static void sysfs_close_driver_device(void *device)
28 sysfs_close_device((struct sysfs_device *)device);
32 * sysfs_close_driver: closes driver and deletes device lists too
33 * @driver: driver to close
35 void sysfs_close_driver(struct sysfs_driver *driver)
38 if (driver->devices != NULL)
39 dlist_destroy(driver->devices);
40 if (driver->directory != NULL)
41 sysfs_close_directory(driver->directory);
47 * open_driver_dir: Open the sysfs_directory for this driver
48 * @driver: Driver whose directory to be opened
49 * Returns 0 on success and 1 on failure
51 static int open_driver_dir(struct sysfs_driver *driver)
57 if (driver->directory == NULL) {
58 driver->directory = sysfs_open_directory(driver->path);
59 if (driver->directory == NULL) {
60 dprintf("Error opening driver directory at %s\n",
69 * alloc_driver: allocates and initializes driver
70 * returns struct sysfs_driver with success and NULL with error.
72 static struct sysfs_driver *alloc_driver(void)
74 return (struct sysfs_driver *)calloc(1, sizeof(struct sysfs_driver));
78 * sysfs_open_driver_path: opens and initializes driver structure
79 * @path: path to driver directory
80 * returns struct sysfs_driver with success and NULL with error
82 struct sysfs_driver *sysfs_open_driver_path(const unsigned char *path)
84 struct sysfs_driver *driver = NULL;
90 if ((sysfs_path_is_dir(path)) != 0) {
91 dprintf("Invalid path to driver: %s\n", path);
94 driver = alloc_driver();
96 dprintf("Error allocating driver at %s\n", path);
99 if ((sysfs_get_name_from_path(path, driver->name,
100 SYSFS_NAME_LEN)) != 0) {
101 dprintf("Error getting driver name from path\n");
105 strcpy(driver->path, path);
111 * sysfs_get_driver_attributes: gets list of attributes for the given driver
112 * @driver: sysfs_driver for which attributes are required
113 * returns a dlist of attributes corresponding to the driver if present
116 struct dlist *sysfs_get_driver_attributes(struct sysfs_driver *driver)
118 if (driver == NULL) {
123 if (driver->directory == NULL) {
124 if ((open_driver_dir(driver)) == 1)
127 if (driver->directory->attributes == NULL) {
128 if ((sysfs_read_dir_attributes(driver->directory)) != 0) {
129 dprintf("Error reading driver attributes\n");
133 if ((sysfs_path_is_dir(driver->path)) != 0) {
134 dprintf("Driver at %s no longer exists\n",
138 if ((sysfs_refresh_attributes
139 (driver->directory->attributes)) != 0) {
140 dprintf("Error refreshing driver attributes\n");
144 return(driver->directory->attributes);
148 * sysfs_get_driver_attr: searches driver's attributes by name
149 * @drv: driver to look through
150 * @name: attribute name to get
151 * returns sysfs_attribute reference on success or NULL with error
153 struct sysfs_attribute *sysfs_get_driver_attr(struct sysfs_driver *drv,
154 const unsigned char *name)
156 struct sysfs_attribute *cur = NULL;
157 struct dlist *attrlist = NULL;
164 attrlist = sysfs_get_driver_attributes(drv);
165 if (attrlist != NULL)
166 cur = sysfs_get_directory_attribute(drv->directory,
167 (unsigned char *)name);
172 * sysfs_get_driver_links: gets list of links from the given driver
173 * @driver: sysfs_driver for which links list is required
174 * returns a dlist of links corresponding to the driver if present
177 struct dlist *sysfs_get_driver_links(struct sysfs_driver *driver)
179 if (driver == NULL) {
183 if (driver->directory == NULL) {
184 if ((open_driver_dir(driver)) == 1)
186 if ((sysfs_read_dir_links(driver->directory)) != 0)
189 return(driver->directory->links);
193 * sysfs_get_driver_devices: open up the list of devices this driver supports
194 * @driver: sysfs_driver for which devices are needed
195 * Returns dlist of devices on SUCCESS or NULL with ERROR
197 struct dlist *sysfs_get_driver_devices(struct sysfs_driver *driver)
199 struct sysfs_link *curlink = NULL;
200 struct sysfs_device *device = NULL;
202 if (driver == NULL) {
207 if (driver->devices != NULL)
208 return (driver->devices);
210 if (driver->directory == NULL) {
211 if ((open_driver_dir(driver)) == 1)
213 if ((sysfs_read_dir_links(driver->directory)) != 0)
216 if (driver->directory->links != NULL) {
217 dlist_for_each_data(driver->directory->links, curlink,
219 device = sysfs_open_device_path(curlink->target);
220 if (device == NULL) {
221 dprintf("Error opening device at %s\n",
225 strcpy(device->driver_name, driver->name);
226 if (driver->devices == NULL)
227 driver->devices = dlist_new_with_delete
228 (sizeof(struct sysfs_device),
229 sysfs_close_driver_device);
230 dlist_unshift(driver->devices, device);
233 return (driver->devices);
237 * sysfs_get_driver_device: looks up a device from a list of driver's devices
238 * and returns its sysfs_device corresponding to it
239 * @driver: sysfs_driver on which to search
240 * @name: name of the device to search
241 * Returns a sysfs_device if found, NULL otherwise
243 struct sysfs_device *sysfs_get_driver_device(struct sysfs_driver *driver,
244 const unsigned char *name)
246 struct sysfs_device *device = NULL;
247 struct dlist *devlist = NULL;
249 if (driver == NULL || name == NULL) {
254 if (driver->devices == NULL) {
255 devlist = sysfs_get_driver_devices(driver);
256 if (devlist == NULL) {
257 dprintf("Error getting driver devices\n");
261 dlist_for_each_data(driver->devices, device, struct sysfs_device) {
262 if (!(strncmp(device->name, name, SYSFS_NAME_LEN)))
269 * get_driver_path: looks up the bus the driver is on and builds path to
271 * @bus: bus on which to search
272 * @drv: driver to look for
273 * @path: buffer to return path to driver
274 * @psize: size of "path"
275 * Returns 0 on success and -1 on error
277 static int get_driver_path(const unsigned char *bus,
278 const unsigned char *drv, unsigned char *path, size_t psize)
280 if (bus == NULL || drv == NULL || path == NULL) {
284 if (sysfs_get_mnt_path(path, psize) != 0) {
285 dprintf("Error getting sysfs mount path\n");
288 if (sysfs_trailing_slash(path) == 0)
290 strcat(path, SYSFS_BUS_NAME);
294 strcat(path, SYSFS_DRIVERS_NAME);
301 * sysfs_open_driver_attr: read the user supplied driver attribute
302 * @bus: bus on which to look
303 * @drv: driver whose attribute has to be read
304 * @attrib: Attribute to be read
305 * Returns struct sysfs_attribute on success and NULL on failure
308 * A call to sysfs_close_attribute() is required to close the
309 * attribute returned and to free memory
311 struct sysfs_attribute *sysfs_open_driver_attr(const unsigned char *bus,
312 const unsigned char *drv, const unsigned char *attrib)
314 struct sysfs_attribute *attribute = NULL;
315 unsigned char path[SYSFS_PATH_MAX];
317 if (bus == NULL || drv == NULL || attrib == NULL) {
322 memset(path, 0, SYSFS_PATH_MAX);
323 if ((get_driver_path(bus, drv, path, SYSFS_PATH_MAX)) != 0) {
324 dprintf("Error getting to driver %s\n", drv);
328 strcat(path, attrib);
329 attribute = sysfs_open_attribute(path);
330 if (attribute == NULL) {
331 dprintf("Error opening attribute %s for driver %s\n",
335 if ((sysfs_read_attribute(attribute)) != 0) {
336 dprintf("Error reading attribute %s for driver %s\n",
338 sysfs_close_attribute(attribute);
345 * sysfs_open_driver: open driver by name, given its bus
346 * @drv_name: Name of the driver
347 * @bus_name: Name of the bus
348 * Returns the sysfs_driver reference on success and NULL on failure
350 struct sysfs_driver *sysfs_open_driver(const unsigned char *drv_name,
351 const unsigned char *bus_name)
353 unsigned char path[SYSFS_PATH_MAX];
354 struct sysfs_driver *driver = NULL;
356 if (drv_name == NULL || bus_name == NULL) {
361 memset(path, 0, SYSFS_PATH_MAX);
362 if ((get_driver_path(bus_name, drv_name, path, SYSFS_PATH_MAX)) != 0) {
363 dprintf("Error getting to driver %s\n", drv_name);
366 driver = sysfs_open_driver_path(path);
367 if (driver == NULL) {
368 dprintf("Error opening driver at %s\n", path);