If acpi_video_handles_brightness_key_presses() was called before
acpi_video_register(), it would use the video_list mutex / list_head
uninitialized.
This patch fixes this by using DEFINE_MUTEX / LIST_HEAD when declaring
these, instead of initializing them runtime from acpi_video_register().
Fixes: 90b066b15e "ACPI / video: Add a acpi_video_handles_brightness_key_presses() helper"
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On systems with an intel video opcode region, the completion used in the
patch this commit reverts will only complete if the i915 driver loads.
If for some reason the i915 driver never loads calls to
acpi_video_handles_brightness_key_presses() may be delayed indefinitely.
This reverts commit aecbd9b1bf ("ACPI / video: driver must be registered
before checking for keypresses") fixing this.
This reintroduces a potential NULL pointer deref due to using an
uninitalized mutex, this is fixed differently in a follow-up patch.
Fixes: aecbd9b1bf (ACPI / video: driver must be registered before checking for keypresses)
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The Toshiba Portege R700 needs disable_backlight_sysfs_if=1, just like
the Toshiba Portege R830. Add a quirk for this.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=21012
Cc: 4.2+ <stable@vger.kernel.org> # 4.2+
Tested-by: Emma Reisz <emmareisz@outlook.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_video_handles_brightness_key_presses() may use an uninitialized mutex.
The error has been reported by lockdep: DEBUG_LOCKS_WARN_ON(l->magic != l).
The function assumes that the video driver has been registered before being
called. As explained in the comment of acpi_video_init(), the registration
of the video class may be defered and thus may not take place in the init
function of the module.
Use completion mechanisms to make sure that
acpi_video_handles_brightness_key_presses() wait for the completion of
acpi_video_register() before using the mutex.
Also get rid of register_count since task completion can replace it.
Signed-off-by: Adrien Schildknecht <adrien+dev@schischi.me>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The Dell Vostro V131 has an especially broken acpi-video implementation.
The backlight control bits work, but when the brightness is changed via
the acpi-video interface the backlight flickers annoyingly before settling
at the new brightness, switching to using the native interface fixes the
flickering so add a quirk for this (the vendor interface has the same
problem).
Brightness keypresses reported through the acpi-video-bus are also broken,
they get reported one event delayed, so if you press the brightness-up
hotkey on the keyboard nothing happens, then if you press brightness-down,
the previous brightness-up event gets reported. Since the keypresses are
also reported via wmi (if active) and via atkbd (when wmi is not active)
add a quirk to simply filter out the delayed (broken) events.
Reported-and-tested-by: Michał Kępień <kernel@kempniu.pl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a module option to disable the reporting of keypresses, in some buggy
firmware implementatinon, the reported events are wrong. E.g. they lag
reality by one event in the case triggering the writing of this patch.
In this case it is better to not forward these wrong events to userspace
(esp.) when there is another source of the same events which is not buggy.
Note this is only intended to work around implementations which send
events which are plain wrong. In some cases we get double events, e.g.
from both acpi-video and the atkbd driver, in this case acpi-video is
considered the canonical source, and the events from the other source
should be filtered (using e.g. /lib/udev/hwdb.d/60-keyboard.hwdb).
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Several drivers want to know if the acpi-video is generating key-presses
for brightness change hotkeys to avoid sending double key-events to
userspace for these. Currently these driver use this construct for this:
if (acpi_video_get_backlight_type() == acpi_backlight_vendor)
report_brightness_key_event();
This indirect way of detecting if acpi-video is active does not make the
code easier to understand, and in some cases it is wrong because just
because the preferred type != vendor does not mean that acpi-video is
actually listening for brightness events, e.g. there may be no acpi-video
bus on the system at all.
This commit adds a acpi_video_handles_brightness_key_presses() helper
function, making the code needing this functionality both easier to read
and more correct.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The firmware of ESPRIMO Mobile M9410 has two video output devices that
have _BCM control method, one is the type of "External Digital Monitor"
while the other is the type of "Internal/Integrated Digital Flat Panel".
Only the 2nd video output device's _BCM control method works, but
since we have created two and the 1st one got picked up by user space,
the backlight functionality is broken. To solve this problem, only
register backlight interface for "Internal/Integrated Digital Flat Panel"
type video output device on this laptop.
Another problem of this laptop is that the IDs listed by the _DOD method
doesn't have bit 31 set, which means it doesn't follow the format
specified by ACPI spec. But the value indicates that it actually follows
that format so I've added a DMI quirk and a module level parameter to
force use the device_id_scheme so that we can get the video output
device's type to do the decision if we should register backlight
interface.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=104121
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Reported-and-tested-by: Christian Scharl <zahlsum-kernelbugs@yahoo.de>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no need to carry potentially outdated Free Software Foundation
mailing address in file headers since the COPYING file includes it.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_video_unregister_backlight() is now only used by video_detect.c
which is part of the same acpi_video module as video.c, make
acpi_video_unregister_backlight() private to this module.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is possible for a native backlight driver to load while
acpi_video_register is running, which may lead to
acpi_video_unregister_backlight being called while acpi_video_register
is running and the 2 racing against eachother.
The register_count variable protects against this, but not in a thread
safe manner, this commit adds locking to make this thread safe.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When builtin there is no guarantee in which order module_init functions
are run, so acpi_video_register() may get called from the i915 driver
(if it is also builtin) before acpi_video_init() gets called, resulting
in the dmi quirks not yet being parsed.
This commit moves the dmi_check_system() call to acpi_video_register(),
so that we can be sure the dmi quirks have always been applied before
probing.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Move the unregistering of the acpi backlight interface on registering of a
native backlight from video.c to video_detect.c where it belongs.
Note this removes support for re-registering the acpi backlight interface
when the native interface goes away. In practice this never happens and
it needlessly complicates the code.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Most of the patch is moving the dmi quirks for forcing use of the
acpi-video / the native backlight interface to video_detect.c.
What remains is a nice cleanup.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is a preparation patch for the backlight interface selection logic
cleanup, there are 2 reasons to not always build the video_detect code
into the kernel:
1) In order for the video_detect.c to also deal with / select native
backlight interfaces on win8 systems, instead of doing this in video.c
where it does not belong, video_detect.c needs to call into the backlight
class code. Which cannot be done if it is builtin and the blacklight class
is not.
2) Currently all the platform/x86 drivers which have quirks to prefer
the vendor driver over acpi-video call acpi_video_unregister_backlight()
to remove the acpi-video backlight interface, this logic really belongs
in video_detect.c, which will cause video_detect.c to depend on symbols of
video.c and video.c already depends on video_detect.c symbols, so they
really need to be a single module.
Note that this commits make 2 changes so as to maintain 100% kernel
commandline compatibility:
1) The __setup call for the acpi_backlight= handling is moved to
acpi/util.c as __setup may only be used by code which is alwasy builtin
2) video.c is renamed to acpi_video.c so that it can be combined with
video_detect.c into video.ko
This commit also makes changes to drivers/platform/x86/Kconfig to ensure
that drivers which use acpi_video_backlight_support() from video_detect.c,
will not be built-in when acpi_video is not built in. This also changes
some "select" uses to "depends on" to avoid dependency loops.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>