Fake "address-of" expressions that evaluate to NULL generally confuse
readers and can provoke compiler warnings.  This patch (as1412)
removes three such fake expressions, using "#ifdef"s in their place.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fixed coding styles in the core usb driver.
Signed-off-by: NCarlos Sánchez Acosta <csanchez@neurowork.net>
Signed-off-by: NAlejandro Sánchez Acosta <asanchez@neurowork.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1403) is a partial reversion of an earlier change
(commit 5f677f1d "USB: fix remote
wakeup settings during system sleep").  After hearing from a user, I
realized that remote wakeup should be enabled during system sleep
whenever userspace allows it, and not only if a driver requests it
too.

Indeed, there could be a device with no driver, that does nothing but
generate a wakeup request when the user presses a button.  Such a
device should be allowed to do its job.

The problem fixed by the earlier patch -- device generating a wakeup
request for no reason, causing system suspend to abort -- was also
addressed by a later patch ("USB: don't enable remote wakeup by
default", accepted but not yet merged into mainline).  The device
won't be able to generate the bogus wakeup requests because it will be
disabled for remote wakeup by default.  Hence this reversion will not
re-introduce any old problems.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org> [.34]
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1387) fixes a bug introduced during the changeover to
the runtime PM framework.  When a driver doesn't support resume or
reset-resume, and consequently its interfaces need to be unbound and
rebound, we have to unbind all the interfaces before trying to rebind
any of them.  Otherwise the driver's probe method for one interface
could try to claim a different interface and fail, because that other
interface hasn't been unbound yet.

This fixes Bugzilla #15788.  The symptom is that some USB sound cards
don't work after hibernation.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NFrançois Valenduc <francois.valenduc@tvcablenet.be>
Cc: stable <stable@kernel.org> [.34]
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1379) reworks the logic for handling USB interface
runtime-PM settings -- hopefully it's right this time!  The problem is
that when a driver is unbound or binding fails, runtime PM for the
interface always gets disabled.  But pm_runtime_disable() nests, so it
shouldn't be called unless the interface was previously enabled for
runtime PM.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NRob Duncan <Robert.Duncan@exar.com>
Tested-by: NRob Duncan <Robert.Duncan@exar.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1362) adjusts the way the USB autosuspend routines
handle remote-wakeup settings.  They aren't supposed to use
device_may_wakeup(); that test is intended only for system sleep, not
runtime power management.  Instead the code checks to see if any
interface drivers need remote wakeup; if they do then it is enabled,
provided the device is capable of it.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The usbcore headers: hcd.h and hub.h are shared between usbcore,
HCDs and a couple of other drivers (e.g. USBIP modules).
So, it makes sense to move them into a more public location and
to cleanup dependency of those modules on kernel internal headers.
This patch moves hcd.h from drivers/usb/core into include/linux/usb/
Signed-of-by: NEric Lescouet <eric@lescouet.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1370) fixes a bug in the USB runtime power management
code.  When a driver claims an interface, it doesn't expect to need to
call usb_autopm_get_interface() or usb_autopm_put_interface() for
runtime PM to work.  Runtime PM can be controlled by the driver's
primary interface; the additional interfaces it claims shouldn't
interfere.  As things stand, the claimed interfaces will prevent the
device from autosuspending.

To fix this problem, the patch sets interfaces to the suspended state
when they are claimed.

Also, although in theory this shouldn't matter, the patch changes the
suspend code so that interfaces are suspended in reverse order from
detection and resuming.  This is how the PM core works, and we ought
to use the same approach.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Debugged-and-tested-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1363) changes the way USB remote wakeup is handled
during system sleeps.  It won't be enabled unless an interface driver
specifically needs it.  Also, it won't be enabled during the FREEZE or
QUIESCE phases of hibernation, when the system doesn't respond to
wakeup events anyway.  Finally, if the device is already
runtime-suspended with remote wakeup enabled, but wakeup is supposed
to be disabled for the system sleep, the device gets woken up so that
it can be suspended again with the proper wakeup setting.

This will fix problems people have reported with certain USB webcams
that generate wakeup requests when they shouldn't, and as a result
cause system suspends to fail.  See

	https://bugs.launchpad.net/ubuntu/+source/linux/+bug/515109Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NErik Andrén <erik.andren@gmail.com>
CC: <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

In the future, we are going to be changing the lock type for struct
device (once we get the lockdep infrastructure properly worked out)  To
make that changeover easier, and to possibly burry the lock in a
different part of struct device, let's create some functions to lock and
unlock a device so that no out-of-core code needs to be changed in the
future.

This patch creates the device_lock/unlock/trylock() functions, and
converts all in-tree users to them.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Magnus Damm <damm@igel.co.jp>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Alex Chiang <achiang@hp.com>
Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrew Patterson <andrew.patterson@hp.com>
Cc: Yu Zhao <yu.zhao@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: CHENG Renquan <rqcheng@smu.edu.sg>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Frans Pop <elendil@planet.nl>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1332) removes an unneeded and annoying debugging message
announcing all USB uevent constructions.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1329) converts the USB stack over to the PM core's
runtime PM framework.  This involves numerous changes throughout
usbcore, especially to hub.c and driver.c.  Perhaps the most notable
change is that CONFIG_USB_SUSPEND now depends on CONFIG_PM_RUNTIME
instead of CONFIG_PM.

Several fields in the usb_device and usb_interface structures are no
longer needed.  Some code which used to depend on CONFIG_USB_PM now
depends on CONFIG_USB_SUSPEND (requiring some rearrangement of header
files).

The only visible change in behavior should be that following a system
sleep (resume from RAM or resume from hibernation), autosuspended USB
devices will be resumed just like everything else.  They won't remain
suspended.  But if they aren't in use then they will naturally
autosuspend again in a few seconds.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1328) reorders the functions in drivers/usb/core/driver.c
so as to put all the routines dependent on CONFIG_PM in one place.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1326) adds usb_enable_autosuspend() and
usb_disable_autosuspend() routines for use by drivers.  If a driver
knows that its device can handle suspends and resumes correctly, it
can enable autosuspend all by itself.  This is equivalent to the user
writing "auto" to the device's power/level attribute.

The implementation differs slightly from what it used to be.  Now
autosuspend is disabled simply by doing usb_autoresume_device() (to
increment the usage counter) and enabled by doing
usb_autosuspend_device() (to decrement the usage counter).

The set_level() attribute method is updated to use the new routines,
and the USB Power-Management documentation is updated.

The patch adds a usb_enable_autosuspend() call to the hub driver's
probe routine, allowing the special-case code for hubs in quirks.c to
be removed.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1323) changes the locking requirements for
usb_autosuspend_device(), usb_autoresume_device(), and
usb_try_autosuspend_device().  This isn't a very important change;
mainly it's meant to make the locking more uniform.

The most tricky part of the patch involves changes to usbdev_open().
To avoid an ABBA locking problem, it was necessary to reduce the
region protected by usbfs_mutex.  Since that mutex now protects only
against simultaneous open and remove, this posed no difficulty -- its
scope was larger than necessary.

And it turns out that usbfs_mutex is no longer needed in
usbdev_release() at all.  The list of usbfs "ps" structures is now
protected by the device lock instead of by usbfs_mutex.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1322) reverses the two outcomes of an "if" statement in
usb_probe_interface(), to avoid an unnecessary level of indentation.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1331) adds non-tree ordering constraints needed for
proper resume of PCI USB host controllers from hibernation.  The main
issue is that non-high-speed devices must not be resumed before the
high-speed root hub, because it is the ehci_bus_resume() routine which
takes care of handing the device connection over to the companion
controller.  If the device resume is attempted before the handover
then the device won't be found and it will be treated as though it had
disconnected.

The patch adds a new field to the usb_bus structure; for each
full/low-speed bus this field will contain a pointer to the companion
high-speed bus (if one exists).  It is used during normal device
resume; if the hs_companion pointer isn't NULL then we wait for the
root-hub device on the hs_companion bus.

A secondary issue is that an EHCI controlller shouldn't be resumed
before any of its companions.  On some machines I have observed
handovers failing if the companion controller is reinitialized after
the handover.  Thus, the EHCI resume routine must wait for the
companion controllers to be resumed.

The patch also fixes a small bug in usb_hcd_pci_probe(); an error path
jumps to the wrong label, causing a memory leak.

[rjw: Fixed compilation for CONFIG_PM_SLEEP unset.]
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Accroding commit 0994375e, which is adding remove_id sysfs attr
for pci drivers, for management tools dynamically bind/unbind
a pci/usb devices to a specified drivers; with this patch,
the management tools can be simplied.

And the original code didn't handle the failure of
usb_create_newid_file, fixed in this patch.
Signed-off-by: NCHENG Renquan <rqcheng@smu.edu.sg>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1303) revises the USB Power Management infrastructure to
make it compatible with the new driver-model Runtime PM framework:

	Drivers are no longer allowed to access intf->pm_usage_cnt
	directly; the PM framework manages its own usage counters.

	usb_autopm_set_interface() is eliminated, because it directly
	sets intf->pm_usage_cnt.

	usb_autopm_enable() and usb_autopm_disable() are eliminated,
	because they call usb_autopm_set_interface().

	usb_autopm_get_interface_no_resume() and
	usb_autopm_put_interface_no_suspend() are added.  They
	correspond to pm_runtime_get_noresume() and
	pm_runtime_put_noidle() in the PM framework.

	The power/level attribute no longer accepts "suspend", only
	"on" and "auto".  The PM framework doesn't allow devices to be
	forced into a suspended mode.

The hub driver contains the only code that violates the new
guidelines.  It is updated to use the new interface routines instead.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1302) removes the auto_pm flag from struct usb_device.
The flag's only purpose was to distinguish between autosuspends and
external suspends, but that information is now available in the
pm_message_t argument passed to suspend methods.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

usb: check for IO errors usb_set_interface can return

if they happen while unbinding a flag is set to retry upon probe
if they happen during probe they are handled as probe errors
Signed-off-by: NOliver Neukum <oliver@neukum.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1260) changes the pm_usage_cnt field in struct
usb_interface from an int to an atomic_t.  This is so that drivers can
invoke the usb_autopm_get_interface_async() and
usb_autopm_put_interface_async() routines without locking and without
fear of corrupting the pm_usage_cnt value.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1258) implements a feature that users have been asking
for: It gives programs the ability to "claim" a port on a hub, via a
new usbfs ioctl.  A device plugged into a "claimed" port will not be
touched by the kernel beyond the immediate necessities of
initialization and enumeration.

In particular, when a device is plugged into a "claimed" port, the
kernel will not select and install a configuration.  And when a config
is installed by usbfs or sysfs, the kernel will not probe any drivers
for any of the interfaces.  (However the kernel will fetch various
string descriptors during enumeration.  One could argue that this
isn't really necessary, but the strings are exported in sysfs.)

The patch does not guarantee exclusive access to these devices; it is
still possible for more than one program to open the device file
concurrently.  Programs are responsible for coordinating access among
themselves.

A demonstration program showing how to use the new interface can be 
found in an attachment to

	http://marc.info/?l=linux-usb&m=124345857431452&w=2

The patch also makes a small simplification to the hub driver,
replacing a bunch of more-or-less useless variants of "out of memory"
with a single message.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Currently if a laptop is suspended e.g. while docked and then resumed after
undocking it, the following errors get generated because the USB hub in the
docking station and the devices connected to it are no longer available:
pm_op(): usb_dev_resume+0x0/0x10 returns -19
PM: Device 1-2 failed to resume: error -19
pm_op(): usb_dev_resume+0x0/0x10 returns -19
PM: Device 1-2.2 failed to resume: error -19
pm_op(): usb_dev_resume+0x0/0x10 returns -19
PM: Device 1-2.3 failed to resume: error -19

As the removal of USB devices while a system is suspended is a relatively
common use case and in most cases not an error, just return success on
-ENODEV. The user gets informed anyway as the USB subsystem generates
regular disconnect messages for the devices shortly afterwards:
usb 1-2: USB disconnect, address 3
usb 1-2.2: USB disconnect, address 4
usblp0: removed
usb 1-2.3: USB disconnect, address 5
Signed-off-by: NFrans Pop <elendil@planet.nl>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The endpoint devices look like simple attribute groups now, and no longer
like devices with a specific subsystem. They will also no longer emit uevents.

It also removes the device node requests for endpoint devices, which are not
implemented for now.
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1230) consolidates code in usb_unbind_interface() and
usb_driver_release_interface().  In fact, it makes release_interface
call unbind_interface, thereby removing the need for duplicated code.

It works like this: If the interface has already been registered with
the driver core when a driver releases it, then the usual driver-core
mechanism will call unbind_interface.  If it hasn't been unregistered
then we will make the call ourselves.

As a nice bonus, drivers now don't have to worry about whether their
disconnect method will get called when they release an interface -- it
always will.  Previously it would be called only if the interface was
registered.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1200) finishes some fixes that were left incomplete by
an earlier patch.

Although nobody has addressed this issue in the past, it turns out
that we need to distinguish between two different modes of disabling
and enabling endpoints.  In one mode only the data structures in
usbcore are affected, and in the other mode the host controller and
device hardware states are affected as well.

The earlier patch added an extra argument to the routines in the
enable_endpoint pathways to reflect this difference.  This patch adds
corresponding arguments to the disable_endpoint pathways.  Without
this change, the endpoint toggle state can get out of sync between
the host and the device.  The exact mechanism depends on the details
of the host controller (whether or not it stores its own copy of the
toggle values).
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NDan Streetman <ddstreet@ieee.org>
Tested-by: NDan Streetman <ddstreet@ieee.org>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1197) fixes an error introduced recently.  Since a
significant number of devices can't handle Set-Interface requests, we
no longer call usb_set_interface() when a driver unbinds from an
interface, provided the interface is already in altsetting 0.  However
the interface still does get disabled, and the call to
usb_set_interface() was the only thing re-enabling it.  Since the
interface doesn't get re-enabled, further attempts to use it fail.

So the patch adds a call to usb_enable_interface() when a driver
unbinds and the interface is in altsetting 0.  For this to work
right, the interface's endpoints have to be re-enabled but their
toggles have to be left alone.  Therefore an additional argument is
added to usb_enable_endpoint() and usb_enable_interface(), a flag
indicating whether or not the endpoint toggles should be reset.

This is a forward-ported version of a patch which fixes Bugzilla
#12301.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NDavid Roka <roka@dawid.hu>
Reported-by: NErik Ekman <erik@kryo.se>
Tested-by: NErik Ekman <erik@kryo.se>
Tested-by: NAlon Bar-Lev <alon.barlev@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1177) modifies the USB core suspend and resume
routines.  The resume functions now will take a pm_message_t argument,
so they will know what sort of resume is occurring.  The new argument
is also passed to the port suspend/resume and bus suspend/resume
routines (although they don't use it for anything but debugging).

In addition, special pm_message_t values are used for user-initiated,
device-initiated (i.e., remote wakeup), and automatic suspend/resume.
By testing these values, drivers can tell whether or not a particular
suspend was an autosuspend.  Unfortunately, they can't do the same for
resumes -- not until the pm_message_t argument is also passed to the
drivers' resume methods.  That will require a bigger change.

IMO, the whole Power Management framework should have been set up this
way in the first place.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1178) uses the new round_jiffies_up_relative() routine
for setting the autosuspend delayed_work timer.  It's appropriate
since we don't care too much about the exact length of the delay, but
we don't want it to be too short (rounded down).
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch introduces a new call to be able to do a USB reset from an
atomic contect. This is quite helpful in USB callbacks to handle
errors (when the only thing that can be done is to do a device
reset).

It is done queuing a work struct that will do the actual reset. The
struct is "attached" to an interface so pending requests from an
interface are removed when said interface is unbound from the driver.

The call flow then becomes:

usb_queue_reset_device()
  __usb_queue_reset_device() [workqueue]
    usb_reset_device()

usb_probe_interface()
  usb_cancel_queue_reset()      [error path]

usb_unbind_interface()
  usb_cancel_queue_reset()

usb_driver_release_interface()
  usb_cancel_queue_reset()

Note usb_cancel_queue_reset() needs smarts to try not to unqueue when
it is actually being executed. This happens when we run the reset from
the workqueue: usb_reset_device() is called and on interface unbind
time, usb_cancel_queue_reset() would be called. That would deadlock on
cancel_work_sync(). To avoid that, we set (before running
usb_reset_device()) usb_intf->reset_running and clear it inmediately
after returning.

Patch is against 2.6.28-rc2 and depends on
http://marc.info/?l=linux-usb&m=122581634925308&w=2 (as submitted by
Alan Stern).
Signed-off-by: NInaky Perez-Gonzalez <inaky@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1160b) adds support routines for asynchronous autosuspend
and autoresume, with accompanying documentation updates.  There
already are several potential users of this interface, and others are
likely to arise as autosuspend support becomes more widespread.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When a driver unbinds from an interface, usbcore always sends a
Set-Interface request to reinstall altsetting 0.  Unforunately, quite
a few devices have buggy firmware that crashes when it receives this
request.

To avoid such problems, this patch (as1180) arranges to send the
Set-Interface request only when the interface is not already in
altsetting 0.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1152) may help prevent some problems associated with the
new policy of unbinding drivers that don't support suspend/resume or
pre_reset/post_reset.  If for any reason the resume or reset fails, and
the device is logically disconnected, there's no point in trying to
rebind the driver.  So the patch checks for success before carrying
out the unbind/rebind.

There was a report from one user that this fixed a problem he was
experiencing, but the details never became fully clear.  In any case,
adding these tests can't hurt.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Reset upon resumption will wipe the input buffer and is therefore
a reason to not suspend if remote wakeup is requested because
the driver needs that data.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1130) fixes an incompatibility between the new PM
infrastructure and USB power management.  We are not allowed to call
drivers' probe routines during a system sleep transition between the
"prepare" and "complete" callbacks, but that's exactly what we do when
a driver doesn't have full suspend/resume support.  Such drivers are
unbound during the "suspend" call and reprobed during the "resume" call.

The patch causes the reprobe step to be skipped if the "complete"
callback hasn't been issued yet, i.e., if the interface's
dev.power.status field is not equal to DPM_ON.  Thus during the
"resume" callback nothing bad will happen, and during the final
"complete" callback the reprobing will occur as desired.

This fixes the problem reported in Bugzilla #11263.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1129) adds support for the new PM callbacks to usbcore.
The new callbacks merely invoke the same old USB power management
routines as the old ones did.

A minor improvement is that the callbacks are present only in the
"USB-device" device_type structure, rather than in the bus_type
structure.  This way they will be invoked only for USB devices, not
for USB interfaces.  The core USB PM routines automatically handle
suspending and resuming interfaces along with their devices.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1128) fixes one of the problems related to the new PM
infrastructure.  We are not allowed to register new child devices
during the middle of a system sleep transition, but unbinding a USB
driver causes the core to automatically install altsetting 0 and
thereby create new endpoint pseudo-devices.

The patch fixes this problem (and the related problem that installing
altsetting 0 will fail if the device is suspended) by deferring the
Set-Interface call until some later time when it is legal and can
succeed.  Possible later times are: when a new driver is being probed
for the interface, and when the interface is being resumed.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>