2 * udev_sysfs.c - sysfs linux kernel specific knowledge
4 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
5 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation version 2 of the License.
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 675 Mass Ave, Cambridge, MA 02139, USA.
32 #include "udev_version.h"
33 #include "udev_sysfs.h"
34 #include "libsysfs/sysfs/libsysfs.h"
36 /* list of subsystem specific files
37 * NULL if there is no file to wait for
39 static struct subsystem_file {
42 } subsystem_files[] = {
43 { .subsystem = "net", .file = "ifindex" },
44 { .subsystem = "scsi_host", .file = "unique_id" },
45 { .subsystem = "scsi_device", .file = NULL },
46 { .subsystem = "pcmcia_socket", .file = "card_type" },
47 { .subsystem = "usb_host", .file = NULL },
48 { .subsystem = "bluetooth", .file = "address" },
49 { .subsystem = "firmware", .file = "data" },
50 { .subsystem = "i2c-adapter", .file = NULL },
51 { .subsystem = "pci_bus", .file = NULL },
52 { .subsystem = "ieee1394", .file = NULL },
53 { .subsystem = "ieee1394_host", .file = NULL },
54 { .subsystem = "ieee1394_node", .file = NULL },
58 int subsystem_expect_no_dev(const char *subsystem)
60 struct subsystem_file *file;
62 for (file = subsystem_files; file->subsystem != NULL; file++)
63 if (strcmp(subsystem, file->subsystem) == 0)
69 /* get subsystem specific files, returns "dev" if no other found */
70 static char *get_subsystem_specific_file(const char *subsystem)
72 struct subsystem_file *file;
74 /* look if we want to look for another file instead of "dev" */
75 for (file = subsystem_files; file->subsystem != NULL; file++)
76 if (strcmp(subsystem, file->subsystem) == 0)
82 /* wait for class pecific file to show up */
83 static int wait_for_class_device_attributes(struct sysfs_class_device *class_dev,
87 char filename[SYSFS_PATH_MAX];
90 file = get_subsystem_specific_file(class_dev->classname);
92 dbg("class '%s' has no file to wait for", class_dev->classname);
96 snprintf(filename, SYSFS_PATH_MAX-1, "%s/%s", class_dev->path, file);
97 dbg("looking at class '%s' for specific file '%s'", class_dev->classname, filename);
99 loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
103 if (stat(class_dev->path, &stats) == -1) {
104 dbg("'%s' now disappeared (probably remove has beaten us)", class_dev->path);
108 if (stat(filename, &stats) == 0) {
109 dbg("class '%s' specific file '%s' found", class_dev->classname, file);
113 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
116 dbg("error: getting class '%s' specific file '%s'", class_dev->classname, file);
118 *error = "class specific file unavailable";
122 /* check if we need to wait for a physical device */
123 static int class_device_expect_no_device_link(struct sysfs_class_device *class_dev)
125 /* list of devices without a "device" symlink to the physical device
126 * if device is set to NULL, no devices in that subsystem has a link */
127 static struct class_device {
131 { .subsystem = "block", .device = "double" },
132 { .subsystem = "block", .device = "nb" },
133 { .subsystem = "block", .device = "ram" },
134 { .subsystem = "block", .device = "loop" },
135 { .subsystem = "block", .device = "fd" },
136 { .subsystem = "block", .device = "md" },
137 { .subsystem = "block", .device = "dos_cd" },
138 { .subsystem = "block", .device = "rflash" },
139 { .subsystem = "block", .device = "rom" },
140 { .subsystem = "block", .device = "rrom" },
141 { .subsystem = "block", .device = "flash" },
142 { .subsystem = "block", .device = "msd" },
143 { .subsystem = "block", .device = "sbpcd" },
144 { .subsystem = "block", .device = "pcd" },
145 { .subsystem = "block", .device = "pf" },
146 { .subsystem = "block", .device = "scd" },
147 { .subsystem = "block", .device = "ubd" },
148 { .subsystem = "block", .device = "dm-" },
149 { .subsystem = "input", .device = "event" },
150 { .subsystem = "input", .device = "mice" },
151 { .subsystem = "input", .device = "mouse" },
152 { .subsystem = "input", .device = "ts" },
153 { .subsystem = "vc", .device = NULL },
154 { .subsystem = "tty", .device = NULL },
155 { .subsystem = "cpuid", .device = "cpu" },
156 { .subsystem = "graphics", .device = "fb" },
157 { .subsystem = "mem", .device = NULL },
158 { .subsystem = "misc", .device = NULL },
159 { .subsystem = "msr", .device = NULL },
160 { .subsystem = "netlink", .device = NULL },
161 { .subsystem = "net", .device = "sit" },
162 { .subsystem = "net", .device = "lo" },
163 { .subsystem = "net", .device = "tap" },
164 { .subsystem = "net", .device = "ipsec" },
165 { .subsystem = "net", .device = "dummy" },
166 { .subsystem = "net", .device = "irda" },
167 { .subsystem = "net", .device = "ppp" },
168 { .subsystem = "net", .device = "tun" },
169 { .subsystem = "net", .device = "pan" },
170 { .subsystem = "net", .device = "bnep" },
171 { .subsystem = "net", .device = "vmnet" },
172 { .subsystem = "ppp", .device = NULL },
173 { .subsystem = "sound", .device = NULL },
174 { .subsystem = "printer", .device = "lp" },
175 { .subsystem = "nvidia", .device = NULL },
176 { .subsystem = "video4linux", .device = "vbi" },
177 { .subsystem = "dvb", .device = NULL },
178 { .subsystem = "lirc", .device = NULL },
179 { .subsystem = "firmware", .device = NULL },
180 { .subsystem = "drm", .device = NULL },
181 { .subsystem = "pci_bus", .device = NULL },
182 { .subsystem = "ieee1394", .device = NULL },
183 { .subsystem = "ieee1394_host", .device = NULL },
184 { .subsystem = "ieee1394_node", .device = NULL },
185 { .subsystem = "raw", .device = NULL },
186 { .subsystem = "zaptel", .device = NULL },
187 { .subsystem = "tiglusb", .device = NULL },
188 { .subsystem = "ppdev", .device = NULL },
189 { .subsystem = "ticables", .device = NULL },
190 { .subsystem = "snsc", .device = NULL },
191 { .subsystem = "staliomem", .device = NULL },
192 { .subsystem = "tape", .device = NULL },
193 { .subsystem = "ip2", .device = NULL },
194 { .subsystem = "tpqic02", .device = NULL },
195 { .subsystem = "dsp56k", .device = NULL },
196 { .subsystem = "zft", .device = NULL },
197 { .subsystem = "adb", .device = NULL },
198 { .subsystem = "cosa", .device = NULL },
199 { .subsystem = "pg", .device = NULL },
200 { .subsystem = "pt", .device = NULL },
201 { .subsystem = "capi", .device = NULL },
204 struct class_device *classdevice;
207 for (classdevice = class_device; classdevice->subsystem != NULL; classdevice++) {
208 if (strcmp(class_dev->classname, classdevice->subsystem) == 0) {
209 /* see if no device in this class is expected to have a device-link */
210 if (classdevice->device == NULL)
213 len = strlen(classdevice->device);
215 /* see if device name matches */
216 if (strncmp(class_dev->name, classdevice->device, len) != 0)
219 /* exact name match */
220 if (strlen(class_dev->name) == len)
223 /* name match with instance number */
224 if (isdigit(class_dev->name[len]))
232 /* skip waiting for the bus */
233 static int class_device_expect_no_bus(struct sysfs_class_device *class_dev)
235 static char *devices_without_bus[] = {
243 for (device = devices_without_bus; *device != NULL; device++) {
244 int len = strlen(*device);
246 if (strncmp(class_dev->classname, *device, len) == 0)
253 /* wait for the bus and for a bus specific file to show up */
254 int wait_for_bus_device(struct sysfs_device *devices_dev,
257 static struct bus_file {
261 { .bus = "scsi", .file = "vendor" },
262 { .bus = "usb", .file = "idVendor" },
263 { .bus = "usb", .file = "iInterface" },
264 { .bus = "usb", .file = "bNumEndpoints" },
265 { .bus = "usb-serial", .file = "detach_state" },
266 { .bus = "ide", .file = "detach_state" },
267 { .bus = "pci", .file = "vendor" },
268 { .bus = "platform", .file = "detach_state" },
269 { .bus = "i2c", .file = "detach_state" },
270 { .bus = "ieee1394", .file = "node_count" },
271 { .bus = "ieee1394", .file = "nodeid" },
272 { .bus = "ieee1394", .file = "address" },
275 struct bus_file *busfile;
278 /* wait for the bus device link to the devices device */
279 loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
281 if (sysfs_get_device_bus(devices_dev) == 0)
284 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
287 dbg("error: getting bus device link");
289 *error = "no bus device link";
292 dbg("bus device link found for bus '%s'", devices_dev->bus);
294 /* wait for a bus specific file to show up */
295 loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
297 int found_bus_type = 0;
299 for (busfile = bus_files; busfile->bus != NULL; busfile++) {
300 if (strcmp(devices_dev->bus, busfile->bus) == 0) {
301 char filename[SYSFS_PATH_MAX];
305 snprintf(filename, SYSFS_PATH_MAX-1, "%s/%s", devices_dev->path, busfile->file);
306 dbg("looking at bus '%s' for specific file '%s'", devices_dev->bus, filename);
308 if (stat(filename, &stats) == 0) {
309 dbg("bus '%s' specific file '%s' found", devices_dev->bus, busfile->file);
314 if (found_bus_type == 0) {
316 *error = "unknown bus";
317 info("error: unknown bus, please report to "
318 "<linux-hotplug-devel@lists.sourceforge.net> '%s'", devices_dev->bus);
321 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
324 dbg("error: getting bus '%s' specific file '%s'", devices_dev->bus, busfile->file);
326 *error = "bus specific file unavailable";
331 struct sysfs_class_device *open_class_device_wait(const char *path)
333 struct sysfs_class_device *class_dev;
336 loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
338 class_dev = sysfs_open_class_device_path(path);
342 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
348 int wait_for_class_device(struct sysfs_class_device *class_dev,
351 struct sysfs_class_device *class_dev_parent;
352 struct sysfs_device *devices_dev = NULL;
355 if (wait_for_class_device_attributes(class_dev, error) != 0)
358 /* skip devices without devices-link */
359 if (class_device_expect_no_device_link(class_dev)) {
360 dbg("no device symlink expected for '%s', ", class_dev->name);
364 /* the symlink may be on the parent device */
365 class_dev_parent = sysfs_get_classdev_parent(class_dev);
366 if (class_dev_parent)
367 dbg("looking at parent device for device link '%s'", class_dev_parent->path);
369 /* wait for the symlink to the devices device */
370 dbg("waiting for symlink to devices device");
371 loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
373 if (class_dev_parent)
374 devices_dev = sysfs_get_classdev_device(class_dev_parent);
376 devices_dev = sysfs_get_classdev_device(class_dev);
381 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
384 dbg(" error: no devices device symlink found");
386 *error = "no device symlink";
389 dbg("device symlink found pointing to '%s'", devices_dev->path);
391 /* wait for the bus value */
392 if (class_device_expect_no_bus(class_dev)) {
393 dbg("no bus device expected for '%s', ", class_dev->classname);
396 return wait_for_bus_device(devices_dev, error);
400 struct sysfs_device *open_devices_device_wait(const char *path)
402 struct sysfs_device *devices_dev;
405 loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
407 devices_dev = sysfs_open_device_path(path);
411 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);