linux-stable.git/drivers/usb/core/sysfs.c, branch v3.5

sysfs: get rid of some lockdep false positives

2012-05-14T19:19:56+00:00

This patch (as1554) fixes a lockdep false-positive report.  The
problem arises because lockdep is unable to deal with the
tree-structured locks created by the device core and sysfs.

This particular problem involves a sysfs attribute method that
unregisters itself, not from the device it was called for, but from a
descendant device.  Lockdep doesn't understand the distinction and
reports a possible deadlock, even though the operation is safe.

This is the sort of thing that would normally be handled by using a
nested lock annotation; unfortunately it's not feasible to do that
here.  There's no sensible way to tell sysfs when attribute removal
occurs in the context of a parent attribute method.

As a workaround, the patch adds a new flag to struct attribute
telling sysfs not to inform lockdep when it acquires a readlock on a
sysfs_dirent instance for the attribute.  The readlock is still
acquired, but lockdep doesn't know about it and hence does not
complain about impossible deadlock scenarios.

Also added are macros for static initialization of attribute
structures with the ignore_lockdep flag set.  The three offending
attributes in the USB subsystem are converted to use the new macros.

Signed-off-by: Alan Stern 
Acked-by: Tejun Heo 
CC: Eric W. Biederman 
CC: Peter Zijlstra 
Signed-off-by: Greg Kroah-Hartman

usb: Add support for indicating whether a port is removable

2012-02-09T16:40:11+00:00

Userspace may want to make policy decisions based on whether or not a
given USB device is removable. Add a per-device member and support
for exposing it in sysfs. Information sources to populate it will be
added later.

Signed-off-by: Matthew Garrett 
Signed-off-by: Greg Kroah-Hartman

switch ->is_visible() to returning umode_t

2012-01-04T03:54:55+00:00

Signed-off-by: Al Viro

usbcore: add sysfs support to xHCI usb2 hardware LPM

2011-09-26T22:51:10+00:00

This patch adds sysfs support to xHCI usb2 hardware LPM, so developer can
enable and disable usb2 hardware LPM manually for test purpose.

Signed-off-by: Andiry Xu 
Signed-off-by: Sarah Sharp 
Signed-off-by: Greg Kroah-Hartman

usb: core: Change usb_create_sysfs_intf_files()' return type to void

2011-04-30T00:24:38+00:00

The usb_create_sysfs_intf_files() function always returned zero even
if it failed to create sysfs fails.  Since this is a desired behaviour
there is no need to return return code at all.  This commit changes
function's return type (form int) to void.

Signed-off-by: Michal Nazarewicz 
Cc: Sergey Senozhatsky 
Signed-off-by: Greg Kroah-Hartman

USB: use the runtime-PM autosuspend implementation

2010-11-16T22:03:41+00:00

This patch (as1428) converts USB over to the new runtime-PM core
autosuspend framework.  One slightly awkward aspect of the conversion
is that USB devices will now have two suspend-delay attributes: the
old power/autosuspend file and the new power/autosuspend_delay_ms
file.  One expresses the delay time in seconds and the other in
milliseconds, but otherwise they do the same thing.  The old attribute
can be deprecated and then removed eventually.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: use sysfs_merge_group for power attributes

2010-11-16T22:02:00+00:00

This patch (as1426) makes use of the new sysfs_merge_group() and
sysfs_unmerge_group() routines to simplify the handling of power
attributes for USB devices.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

sysfs: add struct file* to bin_attr callbacks

2010-05-21T16:37:31+00:00

This allows bin_attr->read,write,mmap callbacks to check file specific data
(such as inode owner) as part of any privilege validation.

Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman

USB: deprecate the power/level sysfs attribute

2010-05-20T20:21:37+00:00

This patch (as1367) deprecates USB's power/level sysfs attribute in
favor of the power/control attribute provided by the runtime PM core.
The two attributes do the same thing.

It would be nice to replace power/level with a symlink to
power/control, but at the moment sysfs doesn't offer any way to do so.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: use PM core routines to enable/disable autosuspend

2010-05-20T20:21:37+00:00

This patch (as1366) replaces the private routines
usb_enable_autosuspend() and usb_disable_autosuspend() with calls to
the standard pm_runtime_allow() and pm_runtime_forbid() functions in
the runtime PM framework.  They do the same thing.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman