Commit Graph

262 Commits

Author SHA1 Message Date
Rafael J. Wysocki 751109aad5 ACPI / video: Change the default for video.use_native_backlight to 1
Now that we're hoping to have resolved all of the problems with
video.use_native_backlight=1, make that the default at last.

Link: http://marc.info/?l=linux-acpi&m=139716088401106&w=2
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-05 22:47:35 +02:00
Hans de Goede 0dc6b96ac2 ACPI / video: Add 4 new models to the use_native_backlight DMI list
Acer Aspire V5-171
References: https://bugzilla.redhat.com/show_bug.cgi?id=983342

Acer Aspire V5-471G
Lenovo Yoga 2 11
Reported-and-tested-by: Vincent Gerris <vgerris@gmail.com>

HP EliteBook 8470p
References: https://bugzilla.redhat.com/show_bug.cgi?id=1093120

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 01:31:33 +02:00
Hans de Goede 1e815db647 ACPI / video: Add use native backlight quirk for the ThinkPad W530
Like all of the other *30 ThinkPad models, the W530 has a broken acpi-video
backlight control. Note in order for this to actually fix things on the
ThinkPad W530 the commit titled:
"nouveau: Don't check acpi_video_backlight_support() before registering backlight"
is also needed.

References: https://bugzilla.redhat.com/show_bug.cgi?id=1093171
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 01:29:01 +02:00
Hans de Goede 53a92ba7e3 ACPI / video: Unregister the backlight device if a raw one shows up later
When video.use_native_backlight=1 and non intel gfx are in use, the raw
backlight device of the gfx driver will show up after acpi-video has done its
acpi_video_verify_backlight_support() check.

This causes video.use_native_backlight=1 to not have the desired result.

This patch fixes this by adding a backlight notifier and when a raw
backlight is registered or unregistered re-doing the
acpi_video_verify_backlight_support() check.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 01:29:01 +02:00
Rafael J. Wysocki 2d8fe6757e Merge back earlier 'acpi-video' material. 2014-05-24 13:27:11 +02:00
Hans de Goede 1b7f37e127 ACPI / video: Add an acpi_video_unregister_backlight function
Add an acpi_video_unregister_backlight function, which only unregisters
the backlight device, and leaves the acpi_notifier in place. Some acpi_vendor
driver need this as they don't want the acpi_video# backlight device, but do
need the acpi-video driver for hotkey handling.

Chances are that this new acpi_video_unregister_backlight() is actually
what existing acpi_vendor drivers have wanted all along. Currently acpi_vendor
drivers which want to disable the acpi_video# backlight device, make 2 calls:

acpi_video_dmi_promote_vendor();
acpi_video_unregister();

The intention here is to make things independent of when acpi_video_register()
gets called. As acpi_video_register() will get called on acpi-video load time
on non intel gfx machines, while it gets called on i915 load time on intel
gfx machines.

This leads to the following 2 interesting scenarios:

 a) intel gfx:
  1) acpi-video module gets loaded (as it is a dependency of acpi_vendor
     and i915)
  2) acpi-video does NOT call acpi_video_register()
  3) acpi_vendor loads (lets assume it loads before i915), calls
     acpi_video_dmi_promote_vendor(); which sets
     ACPI_VIDEO_BACKLIGHT_DMI_VENDOR
  4) calls acpi_video_unregister -> not registered, nop
  5) i915 loads, calls acpi_video_register
  6) acpi_video_register registers the acpi_notifier for the hotkeys,
     does NOT register a backlight device because of
     ACPI_VIDEO_BACKLIGHT_DMI_VENDOR

 b) non intel gfx
  1) acpi-video module gets loaded (as it is a dependency acpi_vendor)
  2) acpi-video calls acpi_video_register()
  3) acpi_video_register registers the acpi_notifier for the hotkeys,
     and a backlight device
  4) acpi_vendor loads, calls acpi_video_dmi_promote_vendor()
  5) calls acpi_video_unregister, this unregisters BOTH the acpi_notifier
     for the hotkeys AND the backlight device

So here we have possibly the same acpi_vendor module, making the same calls,
but with different results, in one cases acpi-video does handle hotkeys,
in the other it does not.

Note that the a) scenario turns into b) if we assume the i915 module loads
before the vendor_acpi module, so we also have different behavior depending
on module loading order!

So as said I believe that quite a few existing acpi_vendor modules really
always want the behavior of a), hence this patch adds a new
acpi_video_unregister_backlight() which gives the behavior of a) independent
of module loading order.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-20 13:41:42 +02:00
Hans de Goede 07d1d29ee1 ACPI / video: Revert native brightness quirk for ThinkPad T530
Seems it helps some users, but causes issues for other users:
https://bugzilla.redhat.com/show_bug.cgi?id=1089545

So lets drop it for now until we've figured out a better fix.

Fixes: 43d9490244 (ACPI / video: Add use_native_backlight quirks for more systems)
References: https://bugzilla.redhat.com/show_bug.cgi?id=1089545
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-16 22:21:49 +02:00
Hans de Goede 99678ed73a ACPI / video: Don't register acpi_video_resume notifier without backlight devices
If we're not going to be registering any backlight devices then
acpi_video_resume is always nop, so don't register it in that case.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-16 15:40:01 +02:00
Aaron Lu 5ff365fb6a ACPI / video: correct DMI tag for Dell Inspiron 7520
The DMI tag used to identify Dell Inspiron 7520 should be product name
instead of product version.

Fixes: 0e9f81d3b7 (ACPI / video: Add systems that should favour native backlight interface)
Reported-and-tested-by: Téo Mazars <teomazars@gmail.com>
References: https://bugzilla.redhat.com/show_bug.cgi?id=909552
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-13 14:10:24 +02:00
Hans de Goede 886129a8ee ACPI / video: change acpi-video brightness_switch_enabled default to 0
acpi-video is unique in that it not only generates brightness up/down
keypresses, but also (sometimes) actively changes the brightness itself.

This presents an inconsistent kernel interface to userspace, basically there
are 2 different scenarios, depending on the laptop model:

 1) On some laptops a brightness up/down keypress means: show a brightness osd
 with the current brightness, iow it is a brightness has changed notification.

 2) Where as on (a lot of) other laptops it means a brightness up/down key was
 pressed, deal with it.

Most of the desktop environments interpret any press as in scenario 2, and
change the brightness up / down as a response to the key events, causing it
to be changed twice, once by acpi-video and once by the DE.

With the new default for video.use_native_backlight we will be moving even
more laptops over to behaving as in scenario 2. Making the remaining laptops
even more of a weird exception. Also note that it is hard to detect scenario
1 properly in userspace, and AFAIK none of the DE-s deals with it.

Therefor this commit changes the default of brightness_switch_enabled to 0
making its behavior consistent with all the other backlight drivers.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-07 01:07:06 +02:00
Hans de Goede 43d9490244 ACPI / video: Add use_native_backlight quirks for more systems
ThinkPad T430: extend the T430s entry to also cover the T430 (note we also
have another entry for T430's with a different DMI_PRODUCT_VERSION).

ThinkPad T430
Reported-and-tested-by: edm <fuffi.il.fuffo@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231

Thinkpad T530
Reported-and-tested-by: Balint Szigeti <balint.szgt@gmail.com>
References: https://bugzilla.redhat.com/show_bug.cgi?id=1089545

Acer Aspire 5742G
Reported-and-tested-by: AnAkkk <anakin.cs@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=35622

Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-06 02:02:42 +02:00
Stephen Chandler Paul 997dd7fe54 ACPI / video: Favor native backlight interface for ThinkPad Helix
Like many other Windows 8 laptops the ThinkPad Helix's backlight has a
broken ACPI interface and can only be properly adjusted by using the
video card's native backlight control. This adds the ThinkPad Helix to
the list of laptops affected with this issue so that
video.use_native_backlight is enabled by default.

Signed-off-by: Stephen Chandler Paul <thatslyude@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-07 14:10:21 +02:00
Hanjun Guo 07070e12cf ACPI: Remove duplicate definitions of PREFIX
We already have a macro for PREFIX of "ACPI: " in
drivers/acpi/internal.h, so remove the duplicate ones
in ACPI drivers when internal.h is included.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-19 02:01:57 +01:00
Aaron Lu 0e9f81d3b7 ACPI / video: Add systems that should favour native backlight interface
Some system's ACPI video backlight control interface is broken and the
native backlight control interface should be used by default. This patch
sets the use_native_backlight parameter to true for those systems so
that video backlight control interface will not be created. For detailed
models that are added here, reference the following list.

Note that the user specified kernel cmdline option will always have the
highest priority, i.e. if use_native_backlight=0 is specified and the
system is in the DMI table, the video module will not skip registering
backlight interface for it.

Thinkpad T430s:
Reported-by: Theodore Tso <tytso@mit.edu>
Reported-and-tested-by: Peter Weber <bugs@ttyhoney.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231
Thinkpad X230:
Reported-and-tested-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231
ThinkPad X1 Carbon:
Reported-and-tested-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
Lenovo Yoga 13:
Reported-by: Lennart Poettering <lennart@poettering.net>
Reported-and-tested-by: Kevin Smith <thirdwiggin@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=63811
Dell Inspiron 7520:
Reported-by: Rinat Ibragimov <ibragimovrinat@mail.ru>
Acer Aspire 5733Z:
Reported-by: <sov.info@mail.ru>
References: https://bugzilla.kernel.org/show_bug.cgi?id=62941
Acer Aspire V5-431:
Reported-by: Thomas Christensen <christensenthomas@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=68751
HP ProBook 4340s:
Reported-and-tested-by: Vladimir Sherenkov <a_12300@mail.ru>
References: http://redmine.russianfedora.pro/issues/1258
HP EliteBook/ProBook 2013 models, ZBook and some others:
Provided-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:33:40 +01:00
Hans de Goede bd8ba20597 ACPI / video: Filter the _BCL table for duplicate brightness values
Some devices have duplicate entries in there brightness levels table, ie
on my Dell Latitude E6430 the table looks like this:

[    3.686060] acpi backlight index   0, val 80
[    3.686095] acpi backlight index   1, val 50
[    3.686122] acpi backlight index   2, val 5
[    3.686147] acpi backlight index   3, val 5
[    3.686172] acpi backlight index   4, val 5
[    3.686197] acpi backlight index   5, val 5
[    3.686223] acpi backlight index   6, val 5
[    3.686248] acpi backlight index   7, val 5
[    3.686273] acpi backlight index   8, val 6
[    3.686332] acpi backlight index   9, val 7
[    3.686356] acpi backlight index  10, val 8
[    3.686380] acpi backlight index  11, val 9
etc.

Notice that brightness values 0-5 are all mapped to 5. This means that
if userspace writes any value between 0 and 5 to the brightness sysfs attribute
and then reads it, it will always return 0, which is somewhat unexpected.

This is a problem for ie gnome-settings-daemon, which uses read-modify-write
logic when the users presses the brightness up or down keys. This is done
this way to take brightness changes from other sources into account.

On this specific laptop what happens once the brightness has been set to 0,
is that gsd reads 0, adds 5, writes 5, and on the next brightness up key press
again reads 0, so things get stuck at the lowest brightness setting.

Filtering out the duplicate table entries, makes any write to brightness
read back as the written value as one would expect, fixing this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-20 01:33:40 +01:00
Lv Zheng 8b48463f89 ACPI: Clean up inclusions of ACPI header files
Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.

First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
should not be included directly from any files that are built for
CONFIG_ACPI unset, because that generally leads to build warnings about
undefined symbols in !CONFIG_ACPI builds.  For CONFIG_ACPI set,
<linux/acpi.h> includes those files and for CONFIG_ACPI unset it
provides stub ACPI symbols to be used in that case.

Second, there are ordering dependencies between those files that always
have to be met.  Namely, it is required that <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there.  And <acpi/acpi.h> which provides
basic ACPICA type declarations should always be included prior to any other
ACPI headers in CONFIG_ACPI builds.  That also is taken care of including
<linux/acpi.h> as appropriate.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07 01:03:14 +01:00
Aaron Lu 545ef368e0 ACPI / video: clean up DMI table for initial black screen problem
With commit 2c62333a40 "ACPI / video: Quirk initial backlight level 0"
we do not need to have the following systems in DMI table, so remove them.
HP Pavilion m4, HP 1000 Notebook PC, HP Pavilion g6 Notebook PC,
HP Pavilion dm4, Fujitsu E753, HP Folio 13-2000.

With this change, the use_bios_initial_backlight module parameter is no
longer needed and thus removed.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Alex Hung <alex.hung@canonical.com> # for HP 1000 Notebook PC
Tested-by: Gustavo Maciel Dias Vieira <gustavo@sagui.org> # for HP Pavilion dm4
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-15 23:23:17 +01:00
Aaron Lu 906f187b93 Revert "ACPI / video: Ignore BIOS initial backlight value for HP 250 G1"
This reverts commit e37f14a5fb.

It turned out other systems also share the same problem with bug 63111
so I made a patch to catch initial brightness level 0 problem. With that
patch applied, we do not need to place HP 250 G1 in DMI table.

References: https://bugzilla.kernel.org/show_bug.cgi?id=63111
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-07 02:14:48 +01:00
Aaron Lu 2c62333a40 ACPI / video: Quirk initial backlight level 0
Some firmware doesn't initialize initial backlight level to a proper
value and _BQC will return 0 on first time evaluation. We used to be
able to detect such incorrect value with our code logic, as value 0
normally isn't a valid value in _BCL. But with the introduction of Win8,
firmware begins to fill _BCL with values from 0 to 100, now 0 becomes
a valid value but that value will make user's screen black. This patch
test initial _BQC for value 0, if such a value is returned, do not use
it.

References: https://bugzilla.kernel.org/show_bug.cgi?id=64031
References: https://bugzilla.kernel.org/show_bug.cgi?id=61231
References: https://bugzilla.kernel.org/show_bug.cgi?id=63111
Reported-by: Qingshuai Tian <qingshuai.tian@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com> # on "Idealpad u330p"
Reported-and-tested-by: <erno@iki.fi> # on "Acer Aspire V5-573G"
Reported-and-tested-by: Kirill Tkhai <tkhai@yandex.ru> # on "HP 250 G1"
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-07 02:14:48 +01:00
Aaron Lu 9efa5e5059 ACPI / video: Fix initial level validity test
When testing if the firmware's initial value is valid, we should use
the corrected level value instead of the raw value returned from
firmware.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-07 02:14:48 +01:00
Kirill Tkhai e37f14a5fb ACPI / video: Ignore BIOS initial backlight value for HP 250 G1
On HP 250 G1 laptops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

References: https://bugzilla.kernel.org/show_bug.cgi?id=63111
Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-25 23:31:19 +02:00
Aaron Lu fbc9fe1b4f ACPI / video: Do not register backlight if win8 and native interface exists
According to Matthew Garrett, "Windows 8 leaves backlight control up
to individual graphics drivers rather than making ACPI calls itself.
There's plenty of evidence to suggest that the Intel driver for
Windows [8] doesn't use the ACPI interface, including the fact that
it's broken on a bunch of machines when the OS claims to support
Windows 8.  The simplest thing to do appears to be to disable the
ACPI backlight interface on these systems".

So for Win8 systems, if there is native backlight control interface
registered by GPU driver, ACPI video does not need to register its own.
Since there are systems that don't work well with this approach, a
parameter for video module named use_native_backlight is introduced and
has the value of false by default. For users who have a broken ACPI
video backlight interface, video.use_native_backlight=1 is needed in
kernel cmdline.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-16 01:16:04 +02:00
Aaron Lu 67b662e189 ACPI / video: seperate backlight control and event interface
The backlight control and event delivery functionality provided by ACPI
video module is mixed together and registered all during video device
enumeration time. As a result, the two functionality are also removed
together on module unload time or by the acpi_video_unregister function.
The two functionalities are actually independent and one may be useful
while the other one may be broken, so it is desirable to seperate the
two functionalities such that it is clear and easy to disable one
functionality without affecting the other one.

APIs to selectively remove backlight control interface and/or event
delivery functionality can be easily added once needed.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-16 01:16:04 +02:00
Rafael J. Wysocki 8a3a53ea89 Merge branch 'acpi-video'
* acpi-video:
  ACPI: blacklist win8 OSI for buggy laptops
  ACPI: blacklist win8 OSI for ASUS Zenbook Prime UX31A
  ACPI / video: drop unused fields from struct acpi_video_brightness_flags
  ACPI / video: remove unnecessary type casting
  ACPI / video: trivial style cleanups
  ACPI / video: trivial costmetic cleanups

Conflicts:
	drivers/acpi/video.c
2013-08-27 01:40:40 +02:00
Rafael J. Wysocki 0c581415b5 Merge branch 'acpi-assorted'
* acpi-assorted:
  ACPI / osl: Kill macro INVALID_TABLE().
  earlycpio.c: Fix the confusing comment of find_cpio_data().
  ACPI / x86: Print Hot-Pluggable Field in SRAT.
  ACPI / thermal: Use THERMAL_TRIPS_NONE macro to replace number
  ACPI / thermal: Remove unused macros in the driver/acpi/thermal.c
  ACPI / thermal: Remove the unused lock of struct acpi_thermal
  ACPI / osl: Fix osi_setup_entries[] __initdata attribute location
  ACPI / numa: Fix __init attribute location in slit_valid()
  ACPI / dock: Fix __init attribute location in find_dock_and_bay()
  ACPI / Sleep: Fix incorrect placement of __initdata
  ACPI / processor: Fix incorrect placement of __initdata
  ACPI / EC: Fix incorrect placement of __initdata
  ACPI / scan: Drop unnecessary label from acpi_create_platform_device()
  ACPI: Move acpi_bus_get_device() from bus.c to scan.c
  ACPI / scan: Allow platform device creation without any IO resources
  ACPI: Cleanup sparse warning on acpi_os_initialize1()
  platform / thinkpad: Remove deprecated hotkey_report_mode parameter
  ACPI: Remove the old /proc/acpi/event interface
2013-08-27 01:29:04 +02:00
Rafael J. Wysocki c92f56cbdf Merge branch 'acpi-cleanup'
* acpi-cleanup: (21 commits)
  ACPI / dock: fix error return code in dock_add()
  ACPI / dock: Drop unnecessary local variable from dock_add()
  ACPI / dock / PCI: Drop ACPI dock notifier chain
  ACPI / dock: Do not check CONFIG_ACPI_DOCK_MODULE
  ACPI / dock: Do not leak memory on falilures to add a dock station
  ACPI: Drop ACPI bus notifier call chain
  ACPI / dock: Rework the handling of notifications
  ACPI / dock: Simplify dock_init_hotplug() and dock_release_hotplug()
  ACPI / dock: Walk list in reverse order during removal of devices
  ACPI / dock: Rework and simplify find_dock_devices()
  ACPI / dock: Drop the hp_lock mutex from struct dock_station
  ACPI: simplify acpiphp driver with new helper functions
  ACPI: simplify dock driver with new helper functions
  ACPI: Export acpi_(bay)|(dock)_match() from scan.c
  ACPI: introduce two helper functions for _EJ0 and _LCK
  ACPI: introduce helper function acpi_execute_simple_method()
  ACPI: introduce helper function acpi_has_method()
  ACPI / dock: simplify dock_create_acpi_device()
  ACPI / dock: mark initialization functions with __init
  ACPI / dock: drop redundant spin lock in dock station object
  ...
2013-08-27 01:25:28 +02:00
Rafael J. Wysocki 168cf0eca4 Revert "ACPI / video: Always call acpi_video_init_brightness() on init"
Revert commit c04c697 (ACPI / video: Always call acpi_video_init_brightness()
on init), because it breaks eDP backlight at 1920x1080 on Acer Aspire S3
for Trevor Bortins.

References: https://bugs.freedesktop.org/show_bug.cgi?id=68355
Reported-and-bisected-by: Trevor Bortins <enabfluw@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-22 23:39:02 +02:00
Rafael J. Wysocki f3ce717e60 Merge back earlier 'acpi-assorted' material 2013-08-14 23:22:45 +02:00
Felipe Contreras b3b301c5fe ACPI / video: improve quirk check in acpi_video_bqc_quirk()
If the _BCL package ordering is descending, the first level
(br->levels[2]) is likely to be 0, and if the number of levels
matches the number of steps, we might confuse a returned level to
mean the index.

For example:

  current_level = max_level = 100
  test_level = 0
  returned level = 100

In this case 100 means the level, not the index, and _BCM failed.
Still, if the _BCL package ordering is descending, the index of
level 0 is also 100, so we assume _BQC is indexed, when it's not.

This causes all _BQC calls to return bogus values causing weird
behavior from the user's perspective.  For example:

xbacklight -set 10; xbacklight -set 20;

would flash to 90% and then slowly down to the desired level (20).

The solution is simple; test anything other than the first level
(e.g. 1).

[rjw: Changelog]
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-04 23:45:39 +02:00
Felipe Contreras d8648caf55 ACPI / video: drop unused fields from struct acpi_video_brightness_flags
The _BCM_use_index and _BCL_use_index fields in struct
acpi_video_brightness_flags are not used, so drop them.

[rjw: Changelog]
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-03 22:28:09 +02:00
Felipe Contreras 7c364e79aa ACPI / video: remove unnecessary type casting
Remove type casting from assignments involving void pointers
in two places in drivers/acpi/video.c.

[rjw: Changelog]
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-03 22:15:21 +02:00
Felipe Contreras 915ea7e414 ACPI / video: trivial style cleanups
Fix several coding style defects in drivers/acpi/video.c:
 - Initialization of static variables.
 - Whitespace in expressions, variable definitions, function
   headers, etc.
 - Positioning of labels.
 - Braces around single statements.

[rjw: Changelog]
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-03 22:12:50 +02:00
Felipe Contreras 21fcb34e28 ACPI / video: trivial costmetic cleanups
Fix whitespace and comments in several places in
drivers/acpi/video.c.

[rjw: Changelog]
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-03 22:07:42 +02:00
Rafael J. Wysocki 8e5c2b776a Revert "ACPI / video / i915: No ACPI backlight if firmware expects Windows 8"
We attempted to address a regression introduced by commit a57f7f9
(ACPICA: Add Windows8/Server2012 string for _OSI method.) after which
ACPI video backlight support doesn't work on a number of systems,
because the relevant AML methods in the ACPI tables in their BIOSes
become useless after the BIOS has been told that the OS is compatible
with Windows 8.  That problem is tracked by the bug entry at:

https://bugzilla.kernel.org/show_bug.cgi?id=51231

Commit 8c5bd7a (ACPI / video / i915: No ACPI backlight if firmware
expects Windows 8) introduced for this purpose essentially prevented
the ACPI backlight support from being used if the BIOS had been told
that the OS was compatible with Windows 8 and the i915 driver was
loaded, in which case the backlight would always be handled by i915.
Unfortunately, however, that turned out to cause problems with
backlight to appear on multiple systems with symptoms indicating that
i915 was unable to control the backlight on those systems as
expected.

For this reason, revert commit 8c5bd7a, but leave the function
acpi_video_backlight_quirks() introduced by it, because another
commit on top of it uses that function.

References: https://lkml.org/lkml/2013/7/21/119
References: https://lkml.org/lkml/2013/7/22/261
References: https://lkml.org/lkml/2013/7/23/429
References: https://lkml.org/lkml/2013/7/23/459
References: https://lkml.org/lkml/2013/7/23/81
References: https://lkml.org/lkml/2013/7/24/27
Reported-and-tested-by: James Hogan <james@albanarts.com>
Reported-and-tested-by: Kamal Mostafa <kamal@canonical.com>
Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Reported-and-tested-by: Steven Newbury <steve@snewbury.org.uk>
Reported-by: Martin Steigerwald <Martin@lichtvoll.de>
Reported-by: Kalle Valo <kvalo@adurom.com>
Tested-by: Joerg Platte <jplatte@naasa.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-26 14:59:20 +02:00
Linus Torvalds ea45ea70b6 ACPI video support fixes for 3.11
- Change from Aaron Lu makes ACPICA export a variable which can be
   used by driver code to determine whether or not the BIOS believes
   that we are compatible with Windows 8.
 
 - Change from Matthew Garrett makes the ACPI video driver initialize
   the ACPI backlight even if it is not going to be used afterward
   (that is needed for backlight control to work on Thinkpads).
 
 - Fix from Rafael J Wysocki implements Windows 8 backlight support
   workaround making i915 take over bakclight control if the firmware
   thinks it's dealing with Windows 8.  Based on the work of multiple
   developers including Matthew Garrett, Chun-Yi Lee, Seth Forshee,
   and Aaron Lu.
 
 - Fix from Aaron Lu makes the kernel follow Windows 8 by informing
   the firmware through the _DOS method that it should not carry out
   automatic brightness changes, so that brightness can be controlled
   by GUI.
 
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Merge tag 'acpi-video-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI video support fixes from Rafael Wysocki:
 "I'm sending a separate pull request for this as it may be somewhat
  controversial.  The breakage addressed here is not really new and the
  fixes may not satisfy all users of the affected systems, but we've had
  so much back and forth dance in this area over the last several weeks
  that I think it's time to actually make some progress.

  The source of the problem is that about a year ago we started to tell
  BIOSes that we're compatible with Windows 8, which we really need to
  do, because some systems shipping with Windows 8 are tested with it
  and nothing else, so if we tell their BIOSes that we aren't compatible
  with Windows 8, we expose our users to untested BIOS/AML code paths.

  However, as it turns out, some Windows 8-specific AML code paths are
  not tested either, because Windows 8 actually doesn't use the ACPI
  methods containing them, so if we declare Windows 8 compatibility and
  attempt to use those ACPI methods, things break.  That occurs mostly
  in the backlight support area where in particular the _BCM and _BQC
  methods are plain unusable on some systems if the OS declares Windows
  8 compatibility.

  [ The additional twist is that they actually become usable if the OS
    says it is not compatible with Windows 8, but that may cause
    problems to show up elsewhere ]

  Investigation carried out by Matthew Garrett indicates that what
  Windows 8 does about backlight is to leave backlight control up to
  individual graphics drivers.  At least there's evidence that it does
  that if the Intel graphics driver is used, so we've decided to follow
  Windows 8 in that respect and allow i915 to control backlight (Daniel
  likes that part).

  The first commit from Aaron Lu makes ACPICA export the variable from
  which we can infer whether or not the BIOS believes that we are
  compatible with Windows 8.

  The second commit from Matthew Garrett prepares the ACPI video driver
  by making it initialize the ACPI backlight even if it is not going to
  be used afterward (that is needed for backlight control to work on
  Thinkpads).

  The third commit implements the actual workaround making i915 take
  over backlight control if the firmware thinks it's dealing with
  Windows 8 and is based on the work of multiple developers, including
  Matthew Garrett, Chun-Yi Lee, Seth Forshee, and Aaron Lu.

  The final commit from Aaron Lu makes us follow Windows 8 by informing
  the firmware through the _DOS method that it should not carry out
  automatic brightness changes, so that brightness can be controlled by
  GUI.

  Hopefully, this approach will allow us to avoid using blacklists of
  systems that should not declare Windows 8 compatibility just to avoid
  backlight control problems in the future.

   - Change from Aaron Lu makes ACPICA export a variable which can be
     used by driver code to determine whether or not the BIOS believes
     that we are compatible with Windows 8.

   - Change from Matthew Garrett makes the ACPI video driver initialize
     the ACPI backlight even if it is not going to be used afterward
     (that is needed for backlight control to work on Thinkpads).

   - Fix from Rafael J Wysocki implements Windows 8 backlight support
     workaround making i915 take over bakclight control if the firmware
     thinks it's dealing with Windows 8.  Based on the work of multiple
     developers including Matthew Garrett, Chun-Yi Lee, Seth Forshee,
     and Aaron Lu.

   - Fix from Aaron Lu makes the kernel follow Windows 8 by informing
     the firmware through the _DOS method that it should not carry out
     automatic brightness changes, so that brightness can be controlled
     by GUI"

* tag 'acpi-video-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: no automatic brightness changes by win8-compatible firmware
  ACPI / video / i915: No ACPI backlight if firmware expects Windows 8
  ACPI / video: Always call acpi_video_init_brightness() on init
  ACPICA: expose OSI version
2013-07-21 10:11:04 -07:00
Lan Tianyu 9657a565a4 ACPI / video: ignore BIOS initial backlight value for Fujitsu E753
The BIOS of FUjitsu E753 reports an incorrect initial backlight value
for WIN8 compatible OS, causing backlight to be dark during startup.
This change causes the incorrect initial value from BIOS to be ignored.

References: https://bugzilla.kernel.org/show_bug.cgi?id=60161
Reported-and-tested-by: Jan Hinnerk Stosch <janhinnerk.stosch@gmail.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Cc: 3.7+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-18 21:43:41 +02:00
Aaron Lu efaa14c7e9 ACPI / video: no automatic brightness changes by win8-compatible firmware
Starting from win8, MS backlight control driver will set bit 2 of the
parameter of control method _DOS, to inform firmware it should not
perform any automatic brightness changes. This mostly affects hotkey
notification deliver - if we do not set this bit, on hotkey press,
firmware may choose to adjust brightness level instead of sending out
notification and doing nothing.

So this patch sets bit 2 when calling _DOS so that GUIs can show the
notification window on hotkey press.  This behavior change is only
necessary for win8 systems.

The MS document on win8 backlight control is here:
http://msdn.microsoft.com/en-US/library/windows/hardware/jj159305

References: https://bugzilla.kernel.org/show_bug.cgi?id=52951
References: https://bugzilla.kernel.org/show_bug.cgi?id=56711
Reported-by: Micael Dias <kam1kaz3@gmail.com>
Reported-by: Dan Garton <dan.garton@gmail.com>
Reported-by: Bob Ziuchkovski <bob.ziuchkovski@gmail.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-18 02:08:16 +02:00
Rafael J. Wysocki 8c5bd7adb2 ACPI / video / i915: No ACPI backlight if firmware expects Windows 8
According to Matthew Garrett, "Windows 8 leaves backlight control up
to individual graphics drivers rather than making ACPI calls itself.
There's plenty of evidence to suggest that the Intel driver for
Windows [8] doesn't use the ACPI interface, including the fact that
it's broken on a bunch of machines when the OS claims to support
Windows 8.  The simplest thing to do appears to be to disable the
ACPI backlight interface on these systems".

There's a problem with that approach, however, because simply
avoiding to register the ACPI backlight interface if the firmware
calls _OSI for Windows 8 may not work in the following situations:
 (1) The ACPI backlight interface actually works on the given system
     and the i915 driver is not loaded (e.g. another graphics driver
     is used).
 (2) The ACPI backlight interface doesn't work on the given system,
     but there is a vendor platform driver that will register its
     own, equally broken, backlight interface if not prevented from
     doing so by the ACPI subsystem.
Therefore we need to allow the ACPI backlight interface to be
registered until the i915 driver is loaded which then will unregister
it if the firmware has called _OSI for Windows 8 (or will register
the ACPI video driver without backlight support if not already
present).

For this reason, introduce an alternative function for registering
ACPI video, acpi_video_register_with_quirks(), that will check
whether or not the ACPI video driver has already been registered
and whether or not the backlight Windows 8 quirk has to be applied.
If the quirk has to be applied, it will block the ACPI backlight
support and either unregister the backlight interface if the ACPI
video driver has already been registered, or register the ACPI
video driver without the backlight interface otherwise.  Make
the i915 driver use acpi_video_register_with_quirks() instead of
acpi_video_register() in i915_driver_load().

This change is based on earlier patches from Matthew Garrett,
Chun-Yi Lee and Seth Forshee and includes a fix from Aaron Lu's.

References: https://bugzilla.kernel.org/show_bug.cgi?id=51231
Tested-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
Tested-by: Yves-Alexis Perez <corsac@debian.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Matthew Garrett <matthew.garrett@nebula.com>
2013-07-18 02:08:06 +02:00
Matthew Garrett c04c697cf1 ACPI / video: Always call acpi_video_init_brightness() on init
We have to call acpi_video_init_brightness() even if we're not going
to initialise the backlight - Thinkpads seem to use this as the
trigger for enabling ACPI notifications rather than handling it in
firmware.

[rjw: Drop the brightness object created by
 acpi_video_init_brightness() if we are not going to use it.]
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-18 01:31:47 +02:00
Thomas Renninger 1696d9dc57 ACPI: Remove the old /proc/acpi/event interface
It is quite some time that this one has been deprecated.
Get rid of it.

Should some really important user be overseen, it may be reverted and
the userspace program worked on first, but it is time to do something
to get rid of this old stuff...

Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Matthew Garrett <matthew.garrett@nebula.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15 13:56:36 +02:00
Jiang Liu 0db9820260 ACPI: introduce helper function acpi_execute_simple_method()
Introduce helper function acpi_execute_simple_method() and use it in
a number of places to simplify code.

[rjw: Changelog]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15 01:33:10 +02:00
Jiang Liu 952c63e951 ACPI: introduce helper function acpi_has_method()
Introduce helper function acpi_has_method() and use it in a number
of places to simplify code.

[rjw: Changelog]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15 01:33:10 +02:00
Rafael J. Wysocki 24071f472d ACPI / scan: Do not bind ACPI drivers to objects with scan handlers
ACPI drivers must not be bound to device objects having scan handlers
attatched to them, so make acpi_device_probe() fail with -EINVAL if the
device object being probed has an ACPI scan handler.

After this change the analogous check introduced into the ACPI video
driver by commit 8c9b7a7 (ACPI / video: Do not bind to device objects
with a scan handler) is not necessary any more and may be dropped, so
drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Tony Luck <tony.luck@gmail.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-06-20 01:25:19 +02:00
Rafael J. Wysocki 8c9b7a7b2f ACPI / video: Do not bind to device objects with a scan handler
With the introduction of ACPI scan handlers, ACPI device objects
with an ACPI scan handler attached to them must not be bound to
by ACPI drivers any more.  Unfortunately, however, the ACPI video
driver attempts to do just that if there is a _ROM ACPI control
method defined under a device object with an ACPI scan handler.

Prevent that from happening by making the video driver's "add"
routine check if the device object already has an ACPI scan handler
attached to it and return an error code in that case.

That is not sufficient, though, because acpi_bus_driver_init() would
then clear the device object's driver_data that may be set by its
scan handler, so for the fix to work acpi_bus_driver_init() has to be
modified to leave driver_data as is on errors.

References: https://bugzilla.kernel.org/show_bug.cgi?id=58091
Bisected-and-tested-by: Dmitry S. Demin <dmitryy.demin@gmail.com>
Reported-and-tested-by: Jason Cassell <bluesloth600@gmail.com>
Tracked-down-by: Aaron Lu <aaron.lu@intel.com>
Cc: 3.9+ <stable@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-06-10 13:00:29 +02:00
Ash Willis 780a6ec640 ACPI / video: ignore BIOS initial backlight value for HP Pavilion g6
This patch addresses kernel bug 56661. BIOS reports an incorrect
backlight value, causing the driver to switch off the backlight
completely during startup. This patch ignores the incorrect value from
BIOS.

References: https://bugzilla.kernel.org/show_bug.cgi?id=56661
Signed-off-by: Ash Willis <ashwillis@programmer.net>
Cc: All <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-01 23:52:44 +02:00
Alex Hung fedbe9bc6f ACPI / video: ignore BIOS initial backlight value for HP m4
On HP m4 lapops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

References: https://bugs.launchpad.net/bugs/1184501
Cc: All <stable@vger.kernel.org>
Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-01 23:52:28 +02:00
Alex Hung 4ef366c583 ACPI video: ignore BIOS initial backlight value for HP 1000
On HP 1000 lapops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

References:: https://bugs.launchpad.net/bugs/1167760
Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-12 14:03:14 +02:00
Aaron Lu 91e13aa370 ACPI: video: correct acpi_video_bus_add error processing
acpi_video_bus_get_devices() may fail due to some video output device
doesn't have the _ADR method, and in this case, the error processing
is to simply free the video structure in acpi_video_bus_add(), while
leaving those already registered video output devices in the wild,
which means for some video output device, we have already registered
a backlight interface and installed a notification handler for it.
So it can happen when user is using this system, on hotkey pressing,
the notification handler will send a keycode through a non-existing
input device, causing kernel freeze.

To solve this problem, free all those already registered video output
devices once something goes wrong in acpi_video_bus_get_devices(), so
that no wild backlight interfaces and notification handlers exist.

References: https://bugzilla.kernel.org/show_bug.cgi?id=51731
Reported-and-tested-by: <i-tek@web.de>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-25 12:53:19 +02:00
Aaron Lu a50188dae3 acpi: video: enhance the quirk detect logic of _BQC
Currently we decide if the _BQC is using index by first setting the
level to maximum, and then check if _BQC returned maximum; if not, we
say it is using index.

This is not true for some buggy systems, where the _BQC method will
always return a constant value(e.g. 0 or 100 for the two broken system)
and thus break the current logic. So this patch tries to enhance the
quirk detect logic for _BQC: we do this by picking a test_level, it can
be the maximum level or the mininum one based on some condition. And we
don't make the assumption that if _BQC returned a value that is not what
we just set, it must be using an index. Instead, we will compare the
value returned from _BQC and if it doesn't match, see if the returned
value is an index. And if still no, clear the capability of _BQC.

References: https://bugzilla.kernel.org/show_bug.cgi?id=42861
References: https://bugzilla.kernel.org/show_bug.cgi?id=56011
Reported-and-tested-by: Artem Savkov <artem.savkov@gmail.com>
Reported-by: Luis Medinas <lmedinas@gmail.com>
Reported-by: Cheppes <cheppes@mailinator.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-22 14:08:32 +02:00
Danny Baumann 994fa63c5b ACPI / video: Fix applying indexed initial brightness value.
The value initially read via _BQC also needs to be offset by 2 to
compensate for the first 2 special items in _BCL. Introduce a helper
function that does the BQC-value-to-level conversion in order to not
needlessly duplicate code.

Signed-off-by: Danny Baumann <dannybaumann@web.de>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-25 00:26:55 +01:00