attributes.
Attributes should be ASCII text files, preferably with only one value
-per file. It is noted that it may not be efficient to contain only
+per file. It is noted that it may not be efficient to contain only one
value per file, so it is socially acceptable to express an array of
values of the same type.
For example, declaring
-static DEVICE_ATTR(foo, 0644, show_foo, store_foo);
+static DEVICE_ATTR(foo, S_IWUSR | S_IRUGO, show_foo, store_foo);
is equivalent to doing:
static struct device_attribute dev_attr_foo = {
.attr = {
.name = "foo",
- .mode = 0644,
+ .mode = S_IWUSR | S_IRUGO,
},
.show = show_foo,
.store = store_foo,
The sysfs directory arrangement exposes the relationship of kernel
data structures.
-The top level sysfs diretory looks like:
+The top level sysfs directory looks like:
block/
bus/
devices/
firmware/
net/
+fs/
devices/ contains a filesystem representation of the device tree. It maps
directly to the internal kernel device tree, which is a hierarchy of
for devices on that particular bus (this assumes that drivers do not
span multiple bus types).
+fs/ contains a directory for some filesystems. Currently each
+filesystem wanting to export attributes must create its own hierarchy
+below fs/ (see ./fuse.txt for an example).
+
More information can driver-model specific features can be found in
Documentation/driver-model/.