As part of the removal of get_driver()/put_driver(), this patch
(as1510) changes driver_find(); it now drops the reference it acquires
before returning. The patch also adjusts all the callers of
driver_find() to remove the now unnecessary calls to put_driver().
In addition, the patch adds a warning to driver_find(): Callers must
make sure the driver they are searching for does not get unloaded
while they are using it. This has always been the case; driver_find()
has never prevented a driver from being unregistered or unloaded.
Hence the patch will not introduce any new bugs. The existing callers
all seem to be okay in this respect, however I don't understand the
video drivers well enough to be certain about them.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Dmitry Torokhov <dmitry.torokhov@gmail.com>
CC: Kyungmin Park <kyungmin.park@samsung.com>
CC: Andy Walls <awalls@md.metrocast.net>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit 8ee294cd9d converted serio
subsystem event handling from using a dedicated thread to using
common workqueue. Unfortunately, this regressed our boot times,
due to the fact that serio jobs take long time to execute. While
the new concurrency managed workqueue code manages long-playing
works just fine and schedules additional workers as needed, such
works wreck havoc among remaining users of flush_scheduled_work().
To solve this problem let's move serio/gameport works from system_wq
to system_long_wq which nobody tries to flush.
Reported-and-tested-by: Hernando Torque <pantherchen@versanet.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
When rebinding a serio driver via sysfs drvctl interface it is
possible for an interrupt to trigger after the disconnect of the
existing driver and before the binding of the new driver. This will
cause the serio interrupt handler to queue a rescan event which will
disconnect the new driver immediately after it is attached.
This change removes pending rescans from the serio event queue after
processing the drvctl request but before releasing the serio mutex.
Reproduction involves issuing a rebind of device port from psmouse
driver to serio_raw driver while generating input to trigger
interrupts. Then checking to see if the corresponding
i8042/serio4/driver is correctly attached to the serio_raw driver
instead of psmouse.
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Instead of creating an exclusive thread to handle serio events (which
happen rarely), let's switch to using common workqueue. With the arrival
of concurrency-managed workqueue infrastructure we are not concerned
that our callers or callees also using workqueue (no deadlocks anymore)
and it should reduce total number of threads in the system.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Some (rare) serio devices need to have multiple serio children. One of
the examples is PS/2 multiplexer present on several TQC STKxxx boards,
which connect PS/2 keyboard and mouse to single tty port.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
pr_xxx() and dev_xxx() helpers ensure that all messages emitted by the
module have consistent prefixes, so let's use them. Also fix some
formatting issues.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
We used to make kseriod freezable to prevent unnecessary attempts at
resuming keyboard and mouse before taking hibernation image when suspend
and hibernation were sharing PM operations. Now that they are separated
and we don't risk resuming during 'thaw' we don't need to freeze kseriod
anymore. This will allow us to start resetting mouse and keyboard a bit
earlier, before rest of the userspace comes back up.
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Serio ports are not being restarted any longer because resume operations
after hibernate do nothing, since the device has not been marked as
suspended. This happens because suspend is only considering the SUSPEND
event but not the FREEZE event.
Note that this driver has still to migrate to dev_pm_ops, but this fixes
this particular bug now.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Current style calls for placing EXPORT_SYMBOL() markings directly
after exported symbol definition; let's follow it.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
When resuming AUX ports psmouse driver calls psmouse_extensions()
to determine if the attached mouse is still the same, which may take
a while to complete for generic mice. Offload the resume process to
kseriod so the rest of the system may continue resuming without
waiting for the mouse.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
That fixes an opps when driver is repeatedly loaded and unloaded in
a tight loop.
Tested-by: Roland Kletzing <devzero@web.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Introduce freezer-friendly wrappers around wait_event_interruptible() and
wait_event_interruptible_timeout(), originally defined in <linux/wait.h>, to
be used in freezable kernel threads. Make some of the freezable kernel
threads use them.
This is necessary for the freezer to stop sending signals to kernel threads,
which is implemented in the next patch.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently, the freezer treats all tasks as freezable, except for the kernel
threads that explicitly set the PF_NOFREEZE flag for themselves. This
approach is problematic, since it requires every kernel thread to either
set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
care for the freezing of tasks at all.
It seems better to only require the kernel threads that want to or need to
be frozen to use some freezer-related code and to remove any
freezer-related code from the other (nonfreezable) kernel threads, which is
done in this patch.
The patch causes all kernel threads to be nonfreezable by default (ie. to
have PF_NOFREEZE set by default) and introduces the set_freezable()
function that should be called by the freezable kernel threads in order to
unset PF_NOFREEZE. It also makes all of the currently freezable kernel
threads call set_freezable(), so it shouldn't cause any (intentional)
change of behaviour to appear. Additionally, it updates documentation to
describe the freezing of tasks more accurately.
[akpm@linux-foundation.org: build fixes]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to take serio->drv_mutex in serio_cleanup() to prevent the
function from being called while driver is in the middle of attaching
to a serio port. Such situation can happen with i8042 and atkbd drivers
if user rapidly presses Ctrl-Alt-Del during system startup, and leads
to kernel oops.
Reported-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
The subsystem rwsem is not used by the driver core at all, so there is
no point in trying to access it.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Let serio subsystem take care of suspending the ports; concentrate
on suspending/resuming the controller itself.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
