Commit Graph

227 Commits

Author SHA1 Message Date
Greg Kroah-Hartman 9d11b13402 USB: mark all struct bus_type as const
Now that the driver core can properly handle constant struct bus_type,
move all of the USB subsystem struct bus_type structures as const,
placing them into read-only memory which can not be modified at runtime.

Cc: Johan Hovold <johan@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: linux-usb@vger.kernel.org
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230313182918.1312597-36-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-23 13:22:00 +01:00
Greg Kroah-Hartman 2a81ada32f driver core: make struct bus_type.uevent() take a const *
The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-27 13:45:52 +01:00
Jilin Yuan a7a9f4c006 usb/core: fix repeated words in comments
Delete the redundant word 'the'.

Signed-off-by: Jilin Yuan <yuanjilin@cdjrlc.com>
Link: https://lore.kernel.org/r/20220716132403.35270-1-yuanjilin@cdjrlc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-27 14:32:29 +02:00
Evan Green 9671d55037 USB: core: Disable remote wakeup for freeze/quiesce
The PM_EVENT_FREEZE and PM_EVENT_QUIESCE messages should cause the
device to stop generating interrupts. USB core was previously allowing
devices that were already runtime suspended to keep remote wakeup
enabled if they had gone down that way. This violates the contract with
pm, and can potentially cause MSI interrupts to be lost.

Change that so that if a device is runtime suspended with remote wakeups
enabled, it will be resumed to ensure remote wakeup is always disabled
across a freeze.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Evan Green <evgreen@chromium.org>
Link: https://lore.kernel.org/r/20220421103751.v3.1.I2c636c4decc358f5e6c27b810748904cc69beada@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-23 10:33:52 +02:00
Razvan Heghedus b1e9e7ebe6 usb: core: Export usb_device_match_id
Export usb_device_match_id so that it can be used for easily matching an
usb_device with a table of IDs.

Signed-off-by: Razvan Heghedus <heghedus.razvan@gmail.com>
Link: https://lore.kernel.org/r/20211213183617.14156-1-heghedus.razvan@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:02:04 +01:00
Wei Ming Chen 9899aa5ba5 usb: core: Fix file path that does not exist
Both driver.c and generic.c are not under drivers/usb/, should
be drivers/usb/core/ instead.

Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
Link: https://lore.kernel.org/r/20211205023529.91165-1-jj251510319013@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-05 14:24:19 +01:00
Johan Hovold aaadc6aea6 USB: core: rename usb_driver_claim_interface() data parameter
It's been almost twenty years since the interface "private data" pointer
was removed in favour of using the driver-data pointer of struct device.

Let's rename the driver-data parameter of usb_driver_claim_interface()
so that it better reflects how it's used.

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210318155406.22399-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23 12:39:39 +01:00
Johan Hovold a2a28c25c2 USB: core: drop outdated interface-binding comment
It's been almost twenty years since USB drivers returned a data pointer
from their probe routines in order to bind to an interface.

Time to update the documentation for usb_driver_claim_interface().

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210318155406.22399-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23 12:39:39 +01:00
Bastien Nocera 0942d59b0a usbcore: Check both id_table and match() when both available
From: Bastien Nocera <hadess@hadess.net>

When a USB device driver has both an id_table and a match() function, make
sure to check both to find a match, first matching the id_table, then
checking the match() function.

This makes it possible to have module autoloading done through the
id_table when devices are plugged in, before checking for further
device eligibility in the match() function.

Cc: <stable@vger.kernel.org> # 5.8
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Co-developed-by: M. Vefa Bicakci <m.v.b@runbox.com>
Tested-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Tested-by: Pan (Pany) YUAN <pany@fedoraproject.org>
Link: https://lore.kernel.org/r/20201022135521.375211-2-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-28 13:24:58 +01:00
Greg Kroah-Hartman 168ae5a74b Merge 5.9-rc8 into usb-next
We need the USB fixes in here as well for testing.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 08:54:36 +02:00
M. Vefa Bicakci 3fce39601a usbcore/driver: Accommodate usbip
Commit 88b7381a93 ("USB: Select better matching USB drivers when
available") inadvertently broke usbip functionality. The commit in
question allows USB device drivers to be explicitly matched with
USB devices via the use of driver-provided identifier tables and
match functions, which is useful for a specialised device driver
to be chosen for a device that can also be handled by another,
more generic, device driver.

Prior, the USB device section of usb_device_match() had an
unconditional "return 1" statement, which allowed user-space to bind
USB devices to the usbip_host device driver, if desired. However,
the aforementioned commit changed the default/fallback return
value to zero. This breaks device drivers such as usbip_host, so
this commit restores the legacy behaviour, but only if a device
driver does not have an id_table and a match() function.

In addition, if usb_device_match is called for a device driver
and device pair where the device does not match the id_table of the
device driver in question, then the device driver will be disqualified
for the device. This allows avoiding the default case of "return 1",
which prevents undesirable probe() calls to a driver even though
its id_table did not match the device.

Finally, this commit changes the specialised-driver-to-generic-driver
transition code so that when a device driver returns -ENODEV, a more
generic device driver is only considered if the current device driver
does not have an id_table and a match() function. This ensures that
"generic" drivers such as usbip_host will not be considered specialised
device drivers and will not cause the device to be locked in to the
generic device driver, when a more specialised device driver could be
tried.

All of these changes restore usbip functionality without regressions,
ensure that the specialised/generic device driver selection logic works
as expected with the usb and apple-mfi-fastcharge drivers, and do not
negatively affect the use of devices provided by dummy_hcd.

Fixes: 88b7381a93 ("USB: Select better matching USB drivers when available")
Cc: <stable@vger.kernel.org> # 5.8
Cc: Bastien Nocera <hadess@hadess.net>
Cc: Valentina Manea <valentina.manea.m@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: <syzkaller@googlegroups.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Link: https://lore.kernel.org/r/20200922110703.720960-5-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-25 16:53:02 +02:00
M. Vefa Bicakci 4df30e7603 usbcore/driver: Fix incorrect downcast
This commit resolves a minor bug in the selection/discovery of more
specific USB device drivers for devices that are currently bound to
generic USB device drivers.

The bug is related to the way a candidate USB device driver is
compared against the generic USB device driver. The code in
is_dev_usb_generic_driver() assumes that the device driver in question
is a USB device driver by calling to_usb_device_driver(dev->driver)
to downcast; however I have observed that this assumption is not always
true, through code instrumentation.

This commit avoids the incorrect downcast altogether by comparing
the USB device's driver (i.e., dev->driver) to the generic USB
device driver directly. This method was suggested by Alan Stern.

This bug was found while investigating Andrey Konovalov's report
indicating usbip device driver misbehaviour with the recently merged
generic USB device driver selection feature. The report is linked
below.

Fixes: d5643d2249 ("USB: Fix device driver race")
Cc: <stable@vger.kernel.org> # 5.8
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Bastien Nocera <hadess@hadess.net>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Valentina Manea <valentina.manea.m@gmail.com>
Cc: <syzkaller@googlegroups.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Link: https://lore.kernel.org/r/20200922110703.720960-4-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-25 16:53:02 +02:00
M. Vefa Bicakci aea850cd35 usbcore/driver: Fix specific driver selection
This commit resolves a bug in the selection/discovery of more
specific USB device drivers for devices that are currently bound to
generic USB device drivers.

The bug is in the logic that determines whether a device currently
bound to a generic USB device driver should be re-probed by a
more specific USB device driver or not. The code in
__usb_bus_reprobe_drivers() used to have the following lines:

  if (usb_device_match_id(udev, new_udriver->id_table) == NULL &&
      (!new_udriver->match || new_udriver->match(udev) != 0))
 		return 0;

  ret = device_reprobe(dev);

As the reader will notice, the code checks whether the USB device in
consideration matches the identifier table (id_table) of a specific
USB device_driver (new_udriver), followed by a similar check, but this
time with the USB device driver's match function. However, the match
function's return value is not checked correctly. When match() returns
zero, it means that the specific USB device driver is *not* applicable
to the USB device in question, but the code then goes on to reprobe the
device with the new USB device driver under consideration. All this to
say, the logic is inverted.

This bug was found by code inspection and instrumentation while
investigating the root cause of the issue reported by Andrey Konovalov,
where usbip took over syzkaller's virtual USB devices in an undesired
manner. The report is linked below.

Fixes: d5643d2249 ("USB: Fix device driver race")
Cc: <stable@vger.kernel.org> # 5.8
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Bastien Nocera <hadess@hadess.net>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Valentina Manea <valentina.manea.m@gmail.com>
Cc: <syzkaller@googlegroups.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Link: https://lore.kernel.org/r/20200922110703.720960-3-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-25 16:52:49 +02:00
Sergey Shtylyov bb0634ece9 usb: core: driver: fix stray tabs in error messages
Commit 8bb54ab573 ("usbcore: add usb_device_driver definition") added
the printk() calls with the error massages spoilt due to the stray tabs
in the middle. Remove these tabs and convert printk() calls to pr_err()
for consistency with the other code, while at it.

Fixes: 8bb54ab573 ("usbcore: add usb_device_driver definition")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/4beb55c4-eb34-7744-155f-033b8f527e23@omprussia.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 16:52:40 +02:00
Bastien Nocera d5643d2249 USB: Fix device driver race
When a new device with a specialised device driver is plugged in, the
new driver will be modprobe()'d but the driver core will attach the
"generic" driver to the device.

After that, nothing will trigger a reprobe when the modprobe()'d device
driver has finished initialising, as the device has the "generic"
driver attached to it.

Trigger a reprobe ourselves when new specialised drivers get registered.

Fixes: 88b7381a93 ("USB: Select better matching USB drivers when available")
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20200818110445.509668-3-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-18 13:09:31 +02:00
Bastien Nocera 77419aa403 USB: Fallback to generic driver when specific driver fails
If ->probe fails for a device specific driver, ask the driver core to
reprobe us, after having flagged the device for the generic driver to be
forced.

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-6-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-12 11:01:55 -08:00
Bastien Nocera 88b7381a93 USB: Select better matching USB drivers when available
Now that USB device drivers can reuse code from the generic USB device
driver, we need to make sure that they get selected rather than the
generic driver. Add an id_table and match vfunc to the usb_device_driver
struct, which will get used to select a better matching driver at
->probe time.

This is a similar mechanism to that used in the HID drivers, with the
generic driver being selected unless there's a better matching one found
in the registered drivers (see hid_generic_match() in
drivers/hid/hid-generic.c).

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-5-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-12 11:01:55 -08:00
Bastien Nocera aeebf2b546 USB: Implement usb_device_match_id()
Match a usb_device with a table of IDs.

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-4-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-12 11:01:55 -08:00
Bastien Nocera c9d503370f USB: Make it possible to "subclass" usb_device_driver
The kernel currenly has only 2 usb_device_drivers, one generic one, one
that completely replaces the generic one to make USB devices usable over
a network.

Use the newly exported generic driver functions when a driver declares
to want them run, in addition to its own code. This makes it possible to
write drivers that extend the generic USB driver.

Note that this patch is not enough for another driver to automatically
get selected.

Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-3-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-12 11:01:54 -08:00
Greg Kroah-Hartman 7d9c1d2f7a USB: add support for dev_groups to struct usb_device_driver
Now that the driver core supports dev_groups for individual drivers,
expose that pointer to struct usb_device_driver to make it easier for USB
drivers to also use it.

Yes, users of usb_device_driver are much rare, but there are instances
already that use custom sysfs files, so adding this support will make
things easier for those drivers.  usbip is one example, hubs might be
another one.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190806144502.17792-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-07 14:05:04 +02:00
Greg Kroah-Hartman b71b283e3d USB: add support for dev_groups to struct usb_driver
Now that the driver core supports dev_groups for individual drivers,
expose that pointer to struct usb_driver to make it easier for USB
drivers to also use it.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190806144502.17792-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-07 14:05:04 +02:00
Alan Stern c2b71462d2 USB: core: Fix bug caused by duplicate interface PM usage counter
The syzkaller fuzzer reported a bug in the USB hub driver which turned
out to be caused by a negative runtime-PM usage counter.  This allowed
a hub to be runtime suspended at a time when the driver did not expect
it.  The symptom is a WARNING issued because the hub's status URB is
submitted while it is already active:

	URB 0000000031fb463e submitted while active
	WARNING: CPU: 0 PID: 2917 at drivers/usb/core/urb.c:363

The negative runtime-PM usage count was caused by an unfortunate
design decision made when runtime PM was first implemented for USB.
At that time, USB class drivers were allowed to unbind from their
interfaces without balancing the usage counter (i.e., leaving it with
a positive count).  The core code would take care of setting the
counter back to 0 before allowing another driver to bind to the
interface.

Later on when runtime PM was implemented for the entire kernel, the
opposite decision was made: Drivers were required to balance their
runtime-PM get and put calls.  In order to maintain backward
compatibility, however, the USB subsystem adapted to the new
implementation by keeping an independent usage counter for each
interface and using it to automatically adjust the normal usage
counter back to 0 whenever a driver was unbound.

This approach involves duplicating information, but what is worse, it
doesn't work properly in cases where a USB class driver delays
decrementing the usage counter until after the driver's disconnect()
routine has returned and the counter has been adjusted back to 0.
Doing so would cause the usage counter to become negative.  There's
even a warning about this in the USB power management documentation!

As it happens, this is exactly what the hub driver does.  The
kick_hub_wq() routine increments the runtime-PM usage counter, and the
corresponding decrement is carried out by hub_event() in the context
of the hub_wq work-queue thread.  This work routine may sometimes run
after the driver has been unbound from its interface, and when it does
it causes the usage counter to go negative.

It is not possible for hub_disconnect() to wait for a pending
hub_event() call to finish, because hub_disconnect() is called with
the device lock held and hub_event() acquires that lock.  The only
feasible fix is to reverse the original design decision: remove the
duplicate interface-specific usage counter and require USB drivers to
balance their runtime PM gets and puts.  As far as I know, all
existing drivers currently do this.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: syzbot+7634edaea4d0b341c625@syzkaller.appspotmail.com
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-19 21:15:13 +02:00
Kai-Heng Feng d7a6c0ce8d USB: Consolidate LPM checks to avoid enabling LPM twice
USB Bluetooth controller QCA ROME (0cf3:e007) sometimes stops working
after S3:
[ 165.110742] Bluetooth: hci0: using NVM file: qca/nvm_usb_00000302.bin
[ 168.432065] Bluetooth: hci0: Failed to send body at 4 of 1953 (-110)

After some experiments, I found that disabling LPM can workaround the
issue.

On some platforms, the USB power is cut during S3, so the driver uses
reset-resume to resume the device. During port resume, LPM gets enabled
twice, by usb_reset_and_verify_device() and usb_port_resume().

Consolidate all checks into new LPM helpers to make sure LPM only gets
enabled once.

Fixes: de68bab4fa ("usb: Don't enable USB 2.0 Link PM by default.”)
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: stable <stable@vger.kernel.org> # after much soaking
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 10:02:56 +01:00
Kai-Heng Feng 7529b2574a USB: Add new USB LPM helpers
Use new helpers to make LPM enabling/disabling more clear.

This is a preparation to subsequent patch.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: stable <stable@vger.kernel.org> # after much soaking
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 10:02:56 +01:00
YueHaibing c36e96bd25 USB: core: remove set but not used variable 'udev'
Fixes gcc '-Wunused-but-set-variable' warning:

drivers/usb/core/driver.c: In function 'usb_driver_claim_interface':
drivers/usb/core/driver.c:513:21: warning:
 variable 'udev' set but not used [-Wunused-but-set-variable]

Since commit c183813fce ("USB: remove LPM management from
usb_driver_claim_interface()"), 'udev' is not used.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-09 16:02:29 +02:00
Alan Stern bd729f9d67 USB: fix error handling in usb_driver_claim_interface()
The syzbot fuzzing project found a use-after-free bug in the USB
core.  The bug was caused by usbfs not unbinding from an interface
when the USB device file was closed, which led another process to
attempt the unbind later on, after the private data structure had been
deallocated.

The reason usbfs did not unbind the interface at the appropriate time
was because it thought the interface had never been claimed in the
first place.  This was caused by the fact that
usb_driver_claim_interface() does not clean up properly when
device_bind_driver() returns an error.  Although the error code gets
passed back to the caller, the iface->dev.driver pointer remains set
and iface->condition remains equal to USB_INTERFACE_BOUND.

This patch adds proper error handling to usb_driver_claim_interface().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: syzbot+f84aa7209ccec829536f@syzkaller.appspotmail.com
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20 12:49:12 +02:00
Alan Stern c183813fce USB: remove LPM management from usb_driver_claim_interface()
usb_driver_claim_interface() disables and re-enables Link Power
Management, but it shouldn't do either one, for the reasons listed
below.  This patch removes the two LPM-related function calls from the
routine.

The reason for disabling LPM in the analogous function
usb_probe_interface() is so that drivers won't have to deal with
unwanted LPM transitions in their probe routine.  But
usb_driver_claim_interface() doesn't call the driver's probe routine
(or any other callbacks), so that reason doesn't apply here.

Furthermore, no driver other than usbfs will ever call
usb_driver_claim_interface() unless it is already bound to another
interface in the same device, which means disabling LPM here would be
redundant.  usbfs doesn't interact with LPM at all.

Lastly, the error return from usb_unlocked_disable_lpm() isn't handled
properly; the code doesn't clean up its earlier actions before
returning.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: 8306095fd2 ("USB: Disable USB 3.0 LPM in critical sections.")
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20 12:49:12 +02:00
Martin Liu 8c97a46af0 driver core: hold dev's parent lock when needed
SoC have internal I/O buses that can't be proved for devices. The
devices on the buses can be accessed directly without additinal
configuration required. This type of bus is represented as
"simple-bus". In some platforms, we name "soc" with "simple-bus"
attribute and many devices are hooked under it described in DT
(device tree).

In commit bf74ad5bc4 ("Hold the device's parent's lock during
probe and remove") to solve USB subsystem lock sequence since
USB device's characteristic. Thus "soc" needs to be locked
whenever a device and driver's probing happen under "soc" bus.
During this period, an async driver tries to probe a device which
is under the "soc" bus would be blocked until previous driver
finish the probing and release "soc" lock. And the next probing
under the "soc" bus need to wait for async finish. Because of
that, driver's async probe for init time improvement will be
shadowed.

Since many devices don't have USB devices' characteristic, they
actually don't need parent's lock. Thus, we introduce a lock flag
in bus_type struct and driver core would lock the parent lock base
on the flag. For USB, we set this flag in usb_bus_type to keep
original lock behavior in driver core.

Async probe could have more benefit after this patch.

Signed-off-by: Martin Liu <liumartin@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-31 10:12:07 +02:00
Mathias Nyman c0f3ed87fd usb: Don't print a warning if interface driver rebind is deferred at resume
Interface drivers like btusb that don't support reset-resume will be
rebound at resume if port was reset. Rebind is done during the pm_ops
.complete callback when probe returns EPROBE_DEFER as default.

Remove the "rebind failed: -517" message.
Device probe will eventually take place later.

[one-liner by Jerry Snitselaar posted in a mailing list question -Mathias]
Suggested-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-07 16:03:15 +01:00
Joe Perches 1ccc417e6c usb: core: Fix logging messages with spurious periods after newlines
Using a period after a newline causes bad output.

Miscellanea:

o Coalesce formats too

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-06 09:21:17 +01:00
Felipe Balbi d9e1e1484a usb: core: introduce a new usb_get_std_status() helper
This new helper is a simple wrapper around usb_get_status(). This
patch is in preparation to adding support for fetching PTM_STATUS
types. No functional changes.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07 15:47:19 +01:00
Greg Kroah-Hartman aa1f3bb567 USB: core: move existing SPDX tags to top of the file
To match the rest of the kernel, the SPDX tags for the drivers/usb/core/
files are moved to the first line of the file.  This makes it more
obvious the tag is present as well as making it match the other 12k
files in the tree with this location.

It also uses // to match the "expected style" as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-03 10:12:26 +01:00
Daniel Drake 8dd8d2c95d USB: Force disconnect Huawei 4G modem during suspend
When going into S3 suspend, the Acer TravelMate P648-M and P648-G3
laptops immediately wake up 3-4 seconds later for no obvious reason.

Unbinding the integrated Huawei 4G LTE modem before suspend avoids
the issue, even though we are not using the modem at all (checked
from rescue.target/runlevel1). The problem also occurs when the option
and cdc-ether modem drivers aren't loaded; it reproduces just with the
base usb driver. Under Windows the system can suspend fine.

Seeking a better fix, we've tried a lot of things, including:
 - Check that the device's power/wakeup is disabled
 - Check that remote wakeup is off at the USB level
 - All the quirks in drivers/usb/core/quirks.c e.g. USB_QUIRK_RESET_RESUME,
   USB_QUIRK_RESET, USB_QUIRK_IGNORE_REMOTE_WAKEUP, USB_QUIRK_NO_LPM.

but none of that makes any difference.

There are no errors in the logs showing any suspend/resume-related issues.
When the system wakes up due to the modem, log-wise it appears to be a
normal resume.

Introduce a quirk to disable the port during suspend when the modem is
detected.

The modem from the P648-G3 model is:
T:  Bus=01 Lev=01 Prnt=01 Port=08 Cnt=04 Dev#=  5 Spd=480  MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=ff MxPS=64 #Cfgs=  3
P:  Vendor=12d1 ProdID=15c3 Rev= 1.02
S:  Manufacturer=Huawei Technologies Co., Ltd.
S:  Product=HUAWEI Mobile
S:  SerialNumber=0123456789ABCDEF
C:  #Ifs= 5 Cfg#= 1 Atr=a0 MxPwr=  2mA
I:  If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=10 Driver=
E:  Ad=82(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:  If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=13 Driver=
E:  Ad=83(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:  If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=12 Driver=
E:  Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:  If#= 3 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=06 Prot=16 Driver=
E:  Ad=86(I) Atr=03(Int.) MxPS=  16 Ivl=2ms
I:  If#= 3 Alt= 1 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=16 Driver=
E:  Ad=86(I) Atr=03(Int.) MxPS=  16 Ivl=2ms
E:  Ad=85(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:  If#= 4 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=1b Driver=
E:  Ad=87(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
C:* #Ifs= 6 Cfg#= 2 Atr=a0 MxPwr=  2mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=cdc_ether
E:  Ad=82(I) Atr=03(Int.) MxPS=  16 Ivl=2ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=06 Prot=00 Driver=cdc_ether
E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=10 Driver=option
E:  Ad=84(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
E:  Ad=83(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 3 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=13 Driver=option
E:  Ad=85(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 4 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=12 Driver=option
E:  Ad=86(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 5 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=1b Driver=option
E:  Ad=87(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
C:  #Ifs= 2 Cfg#= 3 Atr=a0 MxPwr=  2mA
A:  FirstIf#= 0 IfCount= 2 Cls=02(comm.) Sub=0e Prot=00
I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=0e Prot=00 Driver=
E:  Ad=82(I) Atr=03(Int.) MxPS=  16 Ivl=2ms
I:  If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=02 Driver=
I:  If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=02 Driver=
E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

Based on an earlier patch by Chris Chiu.

Signed-off-by: Daniel Drake <drake@endlessm.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-23 11:32:34 +02:00
Guenter Roeck f5cccf4942 usb: hub: Do not attempt to autosuspend disconnected devices
While running a bind/unbind stress test with the dwc3 usb driver on rk3399,
the following crash was observed.

Unable to handle kernel NULL pointer dereference at virtual address 00000218
pgd = ffffffc00165f000
[00000218] *pgd=000000000174f003, *pud=000000000174f003,
				*pmd=0000000001750003, *pte=00e8000001751713
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in: uinput uvcvideo videobuf2_vmalloc cmac
ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat rfcomm
xt_mark fuse bridge stp llc zram btusb btrtl btbcm btintel bluetooth
ip6table_filter mwifiex_pcie mwifiex cfg80211 cdc_ether usbnet r8152 mii joydev
snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device ppp_async
ppp_generic slhc tun
CPU: 1 PID: 29814 Comm: kworker/1:1 Not tainted 4.4.52 #507
Hardware name: Google Kevin (DT)
Workqueue: pm pm_runtime_work
task: ffffffc0ac540000 ti: ffffffc0af4d4000 task.ti: ffffffc0af4d4000
PC is at autosuspend_check+0x74/0x174
LR is at autosuspend_check+0x70/0x174
...
Call trace:
[<ffffffc00080dcc0>] autosuspend_check+0x74/0x174
[<ffffffc000810500>] usb_runtime_idle+0x20/0x40
[<ffffffc000785ae0>] __rpm_callback+0x48/0x7c
[<ffffffc000786af0>] rpm_idle+0x1e8/0x498
[<ffffffc000787cdc>] pm_runtime_work+0x88/0xcc
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40

Source:

(gdb) l *0xffffffc00080dcc0
0xffffffc00080dcc0 is in autosuspend_check
(drivers/usb/core/driver.c:1778).
1773		/* We don't need to check interfaces that are
1774		 * disabled for runtime PM.  Either they are unbound
1775		 * or else their drivers don't support autosuspend
1776		 * and so they are permanently active.
1777		 */
1778		if (intf->dev.power.disable_depth)
1779			continue;
1780		if (atomic_read(&intf->dev.power.usage_count) > 0)
1781			return -EBUSY;
1782		w |= intf->needs_remote_wakeup;

Code analysis shows that intf is set to NULL in usb_disable_device() prior
to setting actconfig to NULL. At the same time, usb_runtime_idle() does not
lock the usb device, and neither does any of the functions in the
traceback. This means that there is no protection against a race condition
where usb_disable_device() is removing dev->actconfig->interface[] pointers
while those are being accessed from autosuspend_check().

To solve the problem, synchronize and validate device state between
autosuspend_check() and usb_disconnect().

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-23 08:13:22 +01:00
Guenter Roeck 245b2eecee usb: hub: Fix error loop seen after hub communication errors
While stress testing a usb controller using a bind/unbind looop, the
following error loop was observed.

usb 7-1.2: new low-speed USB device number 3 using xhci-hcd
usb 7-1.2: hub failed to enable device, error -108
usb 7-1-port2: cannot disable (err = -22)
usb 7-1-port2: couldn't allocate usb_device
usb 7-1-port2: cannot disable (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
** 57 printk messages dropped ** hub 7-1:1.0: activate --> -22
** 82 printk messages dropped ** hub 7-1:1.0: hub_ext_port_status failed (err = -22)

This continues forever. After adding tracebacks into the code,
the call sequence leading to this is found to be as follows.

[<ffffffc0007fc8e0>] hub_activate+0x368/0x7b8
[<ffffffc0007fceb4>] hub_resume+0x2c/0x3c
[<ffffffc00080b3b8>] usb_resume_interface.isra.6+0x128/0x158
[<ffffffc00080b5d0>] usb_suspend_both+0x1e8/0x288
[<ffffffc00080c9c4>] usb_runtime_suspend+0x3c/0x98
[<ffffffc0007820a0>] __rpm_callback+0x48/0x7c
[<ffffffc00078217c>] rpm_callback+0xa8/0xd4
[<ffffffc000786234>] rpm_suspend+0x84/0x758
[<ffffffc000786ca4>] rpm_idle+0x2c8/0x498
[<ffffffc000786ed4>] __pm_runtime_idle+0x60/0xac
[<ffffffc00080eba8>] usb_autopm_put_interface+0x6c/0x7c
[<ffffffc000803798>] hub_event+0x10ac/0x12ac
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40

kick_hub_wq() is called from hub_activate() even after failures to
communicate with the hub. This results in an endless sequence of
hub event -> hub activate -> wq trigger -> hub event -> ...

Provide two solutions for the problem.

- Only trigger the hub event queue if communication with the hub
  is successful.
- After a suspend failure, only resume already suspended interfaces
  if the communication with the device is still possible.

Each of the changes fixes the observed problem. Use both to improve
robustness.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-23 08:13:22 +01:00
Greg Kroah-Hartman b65fba3d87 USB: core: add missing license information to some files
Some of the USB core files were missing explicit license information.
As all files in the kernel tree are implicitly licensed under the
GPLv2-only, be explicit in case someone get confused looking at
individual files by using the SPDX nomenclature.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-29 12:51:56 -04:00
Alan Stern 6fb650d43d USB: leave LPM alone if possible when binding/unbinding interface drivers
When a USB driver is bound to an interface (either through probing or
by claiming it) or is unbound from an interface, the USB core always
disables Link Power Management during the transition and then
re-enables it afterward.  The reason is because the driver might want
to prevent hub-initiated link power transitions, in which case the HCD
would have to recalculate the various LPM parameters.  This
recalculation takes place when LPM is re-enabled and the new
parameters are sent to the device and its parent hub.

However, if the driver does not want to prevent hub-initiated link
power transitions then none of this work is necessary.  The parameters
don't need to be recalculated, and LPM doesn't need to be disabled and
re-enabled.

It turns out that disabling and enabling LPM can be time-consuming,
enough so that it interferes with user programs that want to claim and
release interfaces rapidly via usbfs.  Since the usbfs kernel driver
doesn't set the disable_hub_initiated_lpm flag, we can speed things up
and get the user programs to work by leaving LPM alone whenever the
flag isn't set.

And while we're improving the way disable_hub_initiated_lpm gets used,
let's also fix its kerneldoc.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Matthew Giassa <matthew@giassa.net>
CC: Mathias Nyman <mathias.nyman@intel.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03 14:32:07 -07:00
Oliver Neukum 0b818e3956 USB: usb_driver_claim_interface: add sanity checking
Attacks that trick drivers into passing a NULL pointer
to usb_driver_claim_interface() using forged descriptors are
known. This thwarts them by sanity checking.

Signed-off-by: Oliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-18 09:19:02 -07:00
Muhammad Falak R Wani 9766f2517e usb: core: driver: Use kmalloc_array
Use kmalloc_array instead of kmalloc to allocate memory for an array.
Also, remove the dev_warn for a memory leak, making the if check more
sleek.

Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 10:47:19 +01:00
Stefan Koch 8d1f8573a3 usb: interface authorization: Control interface probing and claiming
Driver probings and interface claims get rejected
if an interface is not authorized.

Signed-off-by: Stefan Koch <stefan.koch10@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-22 12:08:40 -07:00
Greg Kroah-Hartman 8c2ea97a3a Revert "usb: interface authorization: Control interface probing and claiming"
This reverts commit de7718bd9c as the
signed-off-by address is invalid.

Cc: Stefan Koch <stefan.koch10@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-18 09:58:26 -07:00
Stefan Koch de7718bd9c usb: interface authorization: Control interface probing and claiming
Driver probings and interface claims get rejected
if an interface is not authorized.

Signed-off-by: Stefan Koch <skoch@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-14 16:55:54 -07:00
Kris Borer 79a02744bc usb: fix coding style issue
Fixed coding style issue: newline after declaration

Signed-off-by: Kris Borer <kborer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-22 14:55:21 -07:00
Alan Stern 074f9dd55f USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd)
Currently the USB stack assumes that all host controller drivers are
capable of receiving wakeup requests from downstream devices.
However, this isn't true for the isp1760-hcd driver, which means that
it isn't safe to do a runtime suspend of any device attached to a
root-hub port if the device requires wakeup.

This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure
and sets the flag in isp1760-hcd.  The core is modified to prevent a
direct child of the root hub from being put into runtime suspend with
wakeup enabled if the flag is set.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Nicolas Pitre <nico@linaro.org>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
2015-01-31 09:05:06 -08:00
Alan Stern 524134d422 USB: don't cancel queued resets when unbinding drivers
The USB stack provides a mechanism for drivers to request an
asynchronous device reset (usb_queue_reset_device()).  The mechanism
uses a work item (reset_ws) embedded in the usb_interface structure
used by the driver, and the reset is carried out by a work queue
routine.

The asynchronous reset can race with driver unbinding.  When this
happens, we try to cancel the queued reset before unbinding the
driver, on the theory that the driver won't care about any resets once
it is unbound.

However, thanks to the fact that lockdep now tracks work queue
accesses, this can provoke a lockdep warning in situations where the
device reset causes another interface's driver to be unbound; see

	http://marc.info/?l=linux-usb&m=141893165203776&w=2

for an example.  The reason is that the work routine for reset_ws in
one interface calls cancel_queued_work() for the reset_ws in another
interface.  Lockdep thinks this might lead to a work routine trying to
cancel itself.  The simplest solution is not to cancel queued resets
when unbinding drivers.

This means we now need to acquire a reference to the usb_interface
when queuing a reset_ws work item and to drop the reference when the
work routine finishes.  We also need to make sure that the
usb_interface structure doesn't outlive its parent usb_device; this
means acquiring and dropping a reference when the interface is created
and destroyed.

In addition, cancelling a queued reset can fail (if the device is in
the middle of an earlier reset), and this can cause usb_reset_device()
to try to rebind an interface that has been deallocated (see
http://marc.info/?l=linux-usb&m=142175717016628&w=2 for details).
Acquiring the extra references prevents this failure.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Reported-by: Olivier Sobrie <olivier@sobrie.be>
Tested-by: Olivier Sobrie <olivier@sobrie.be>
Cc: stable <stable@vger.kernel.org> # 3.19
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-25 20:54:17 +08:00
Rafael J. Wysocki ceb6c9c862 USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM (or even dropped in some cases).

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the USB core code
and documentation.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-04 00:51:54 +01:00
Alan Stern 1299cff9fa USB: shutdown all URBs after controller death
When a host controller dies, we don't need to wait for a driver to
time out.  We can shut down its URBs immediately.  Without this
change, we can end up waiting 30 seconds for a mass-storage transfer
to time out.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-17 16:59:27 -07:00
Alan Stern 8ef42ddd9a USB: Avoid runtime suspend loops for HCDs that can't handle suspend/resume
Not all host controller drivers have bus-suspend and bus-resume
methods.  When one doesn't, it will cause problems if runtime PM is
enabled in the kernel.  The PM core will attempt to suspend the
controller's root hub, the suspend will fail because there is no
bus-suspend routine, and a -EBUSY error code will be returned to the
PM core.  This will cause the suspend attempt to be repeated shortly
thereafter, in a never-ending loop.

Part of the problem is that the original error code -ENOENT gets
changed to -EBUSY in usb_runtime_suspend(), on the grounds that the PM
core will interpret -ENOENT as meaning that the root hub has gotten
into a runtime-PM error state.  While this change is appropriate for
real USB devices, it's not such a good idea for a root hub.  In fact,
considering the root hub to be in a runtime-PM error state would not
be far from the truth.  Therefore this patch updates
usb_runtime_suspend() so that it adjusts error codes only for
non-root-hub devices.

Furthermore, the patch attempts to prevent the problem from occurring
in the first place by not enabling runtime PM by default for root hubs
whose host controller driver doesn't have bus_suspend and bus_resume
methods.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Will Deacon <will.deacon@arm.com>
Tested-by: Will Deacon <will.deacon@arm.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-24 04:06:00 +09:00
Alan Stern 6aec044cc2 USB: unbind all interfaces before rebinding any
When a driver doesn't have pre_reset, post_reset, or reset_resume
methods, the USB core unbinds that driver when its device undergoes a
reset or a reset-resume, and then rebinds it afterward.

The existing straightforward implementation can lead to problems,
because each interface gets unbound and rebound before the next
interface is handled.  If a driver claims additional interfaces, the
claim may fail because the old binding instance may still own the
additional interface when the new instance tries to claim it.

This patch fixes the problem by first unbinding all the interfaces
that are marked (i.e., their needs_binding flag is set) and then
rebinding all of them.

The patch also makes the helper functions in driver.c a little more
uniform and adjusts some out-of-date comments.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: "Poulain, Loic" <loic.poulain@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17 16:08:27 -07:00
Hans de Goede 6343e8bf09 usb-core: Free bulk streams on interface release
Documentation/usb/bulk-streams.txt says:

All stream IDs will be deallocated when the driver releases the interface, to
ensure that drivers that don't support streams will be able to use the endpoint

This commit actually implements this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2014-03-04 15:38:03 -08:00