Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt
index a1426ca..ddf15b1 100644
--- a/Documentation/filesystems/sysfs.txt
+++ b/Documentation/filesystems/sysfs.txt
@@ -116,6 +116,27 @@
.store = store_foo,
};
+Note as stated in include/linux/kernel.h "OTHER_WRITABLE? Generally
+considered a bad idea." so trying to set a sysfs file writable for
+everyone will fail reverting to RO mode for "Others".
+
+For the common cases sysfs.h provides convenience macros to make
+defining attributes easier as well as making code more concise and
+readable. The above case could be shortened to:
+
+static struct device_attribute dev_attr_foo = __ATTR_RW(foo);
+
+the list of helpers available to define your wrapper function is:
+__ATTR_RO(name): assumes default name_show and mode 0444
+__ATTR_WO(name): assumes a name_store only and is restricted to mode
+ 0200 that is root write access only.
+__ATTR_RO_MODE(name, mode): fore more restrictive RO access currently
+ only use case is the EFI System Resource Table
+ (see drivers/firmware/efi/esrt.c)
+__ATTR_RW(name): assumes default name_show, name_store and setting
+ mode to 0644.
+__ATTR_NULL: which sets the name to NULL and is used as end of list
+ indicator (see: kernel/workqueue.c)
Subsystem-Specific Callbacks
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -298,7 +319,7 @@
a stat(2) operation.
More information can driver-model specific features can be found in
-Documentation/driver-model/.
+Documentation/driver-api/driver-model/.
TODO: Finish this section.
@@ -344,7 +365,9 @@
Declaring:
-BUS_ATTR(_name, _mode, _show, _store)
+static BUS_ATTR_RW(name);
+static BUS_ATTR_RO(name);
+static BUS_ATTR_WO(name);
Creation/Removal: