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: NTheodore Tso <tytso@mit.edu>
Reported-and-tested-by: NPeter Weber <bugs@ttyhoney.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231
Thinkpad X230:
Reported-and-tested-by: NIgor Gnatenko <i.gnatenko.brain@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=51231
ThinkPad X1 Carbon:
Reported-and-tested-by: NIgor Gnatenko <i.gnatenko.brain@gmail.com>
Lenovo Yoga 13:
Reported-by: NLennart Poettering <lennart@poettering.net>
Reported-and-tested-by: NKevin Smith <thirdwiggin@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=63811
Dell Inspiron 7520:
Reported-by: NRinat 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: NThomas Christensen <christensenthomas@gmail.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=68751
HP ProBook 4340s:
Reported-and-tested-by: NVladimir Sherenkov <a_12300@mail.ru>
References: http://redmine.russianfedora.pro/issues/1258
HP EliteBook/ProBook 2013 models, ZBook and some others:
Provided-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NAaron Lu <aaron.lu@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

On HP EliteBook Revolve 810 the ACPI backlight device doesn't work as
expected. For example when resuming from system sleep, it seems to lose
backlight settings.

Forcing Intel driver fixes the problem so add this machine the ACPI
video detect blacklist.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Correct "**retyurn_value" to "**return_value".
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

On the Yoga 13 the backlight control doesn't work via ACPI. (And doesn't
work either with the low-level platform driver ideapad_laptop; but
works correctly via the intel video driver).  This patch hence adds the
Yoga 13 to the ACPI video detect blacklist, to make sure the broken ACPI
backlight device is never exposed to userspace.

Note that this appears unrelated to the Windows 8 backlight issues tracked
here:

https://bugzilla.kernel.org/show_bug.cgi?id=51231
https://bugzilla.kernel.org/show_bug.cgi?id=60682

The Yoga's ACPI backlight controls work neither with nor without
acpi_osi="!Windows 2012" on the kernel command line. It appears that
backlight control via the EC simply is not available at all, regardless
whether done via ACPI or via the vendor driver.
Signed-off-by: NLennart Poettering <lennart@poettering.net>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NAaron Lu <aaron.lu@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We attempted to address a regression introduced by commit a57f7f91
(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 8c5bd7ad (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 8c5bd7ad, 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/2013/7/24/27Reported-and-tested-by: NJames Hogan <james@albanarts.com>
Reported-and-tested-by: NKamal Mostafa <kamal@canonical.com>
Reported-and-tested-by: NJörg Otte <jrg.otte@gmail.com>
Reported-and-tested-by: NSteven Newbury <steve@snewbury.org.uk>
Reported-by: NMartin Steigerwald <Martin@lichtvoll.de>
Reported-by: NKalle Valo <kvalo@adurom.com>
Tested-by: NJoerg Platte <jplatte@naasa.net>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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=51231Tested-by: NAaron Lu <aaron.lu@intel.com>
Tested-by: NIgor Gnatenko <i.gnatenko.brain@gmail.com>
Tested-by: NYves-Alexis Perez <corsac@debian.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NAaron Lu <aaron.lu@intel.com>
Acked-by: NMatthew Garrett <matthew.garrett@nebula.com>

Introduce helper function acpi_has_method() and use it in a number
of places to simplify code.

[rjw: Changelog]
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Like on UL30VT, the ACPI video driver can't control backlight correctly on
Asus UL30A.  Vendor driver (asus-laptop) can work.  This patch is to
add "Asus UL30A" to ACPI video detect blacklist in order to use
asus-laptop for video control on the "Asus UL30A" rather than ACPI
video driver.
Signed-off-by: NBastian Triller <bastian.triller@gmail.com>
Cc: All <stable@vger.kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch updates the internal operations of acpi_device_set_id()
to setup acpi_device_pnp without using acpi_device.  There is no
functional change to acpi_device_set_id() in this patch.

acpi_pnp_type is added to acpi_device_pnp, so that PNPID type is
self-contained within acpi_device_pnp.  acpi_add_id(), acpi_bay_match(),
acpi_dock_match(), acpi_ibm_smbus_match() and acpi_is_video_device()
are changed to take acpi_handle as an argument, instead of acpi_device.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI video driver can't control backlight correctly on
Asus UL30VT.  Vendor driver (asus-laptop) can work.  This patch is to
add "Asus UL30VT" to ACPI video detect blacklist in order to use
asus-laptop for video control on the "Asus UL30VT" rather than ACPI
video driver.

References: https://bugzilla.kernel.org/show_bug.cgi?id=32592Reported-by: NAlex Williamson <alex.williamson@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

On Samsung X360, the BIOS will set a flag (VDRV) if the generic
ACPI backlight device is used. This flag will definitively break
the backlight interface (even the vendor interface) untill next
reboot. It's why we should prevent video.ko from being used here
and we can't rely on a later call to acpi_video_unregister().
Signed-off-by: NCorentin Chary <corentin.chary@gmail.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

Instead of adding a big blacklist in video_detect.c to set
ACPI_VIDEO_BACKLIGHT_DMI_VENDOR correctly, let external modules
promote or demote themselves when they know the generic video
module won't work.

Currently drivers where using acpi_video_unregister() directly
but:
- That didn't respect any acpi_backlight=[video|vendor] parameter
  provided by the user.
- Any later call to acpi_video_register() would still re-load the
  generic video module (and some gpu drivers are doing that).

This patch fix those two issues.
Signed-off-by: NCorentin Chary <corentin.chary@gmail.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

asus_acpi only support old models, it has been deprecated since
2009 in favor of asus-laptop, it's not built by any (sane) distro,
so it is time to say good bye.

Thanks to Julien Lerouge and Karol Kozimor for the work they have
done on it, I would never have wrote asus-laptop and other asus
related drivers without asus_acpi.
Signed-off-by: NCorentin Chary <corentin.chary@gmail.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

These files were relying on module.h to come in via the path
in an include/acpi header file, but we don't want to have
instances of module.h being included from include/* files
if it can be avoided.  Have the files include export.h instead.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

This patch reverts one hunk of 677bd810
"ACPI video: remove output switching control", namely the removal of
probing for _DOS/_DOD when searching for video devices.

This is needed on some Fujitsu Laptops (at least S7110, P8010) for the
ACPI backlight interface to work, as an these machines, neither ROM nor
posting methods are available, and after removal of output switching,
none of the caps triggers, which prevents the backlight search from
being entered.

Tested on a Fujitsu Lifebook S7110 and Fujitsu Lifebook P8010.
This probably fixes https://bugzilla.kernel.org/show_bug.cgi?id=27312
for the people who have no entry in /sys/class/backlight.

This is the complete list of public (starting with "_") methods implemented
on the S7110, BIOS rev 1.34:

\_SB_.PCI0.GFX0._ADR
\_SB_.PCI0.GFX0._DOS
\_SB_.PCI0.GFX0._DOD
\_SB_.PCI0.GFX0.CRT._ADR
\_SB_.PCI0.GFX0.CRT._DCS
\_SB_.PCI0.GFX0.CRT._DGS
\_SB_.PCI0.GFX0.CRT._DSS
\_SB_.PCI0.GFX0.LCD._ADR
\_SB_.PCI0.GFX0.LCD._BCL
\_SB_.PCI0.GFX0.LCD._BCM
\_SB_.PCI0.GFX0.LCD._BQC
\_SB_.PCI0.GFX0.LCD._DCS
\_SB_.PCI0.GFX0.LCD._DGS
\_SB_.PCI0.GFX0.LCD._DSS
\_SB_.PCI0.GFX0.LCD._PS0
\_SB_.PCI0.GFX0.LCD._PS3
\_SB_.PCI0.GFX0.TV._ADR
\_SB_.PCI0.GFX0.TV._DCS
\_SB_.PCI0.GFX0.TV._DGS
\_SB_.PCI0.GFX0.TV._DSS
\_SB_.PCI0.GFX0.DVI._ADR
\_SB_.PCI0.GFX0.DVI._DCS
\_SB_.PCI0.GFX0.DVI._DGS
\_SB_.PCI0.GFX0.DVI._DSS
Signed-off-by: NMichael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Acked-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Remove the ACPI video output switching control as it never works.

With the patch applied,
ACPI video driver still catches the video output notification,
but it does nothing but raises the notification to userspace.
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Fix a vague warning message.

https://bugzilla.kernel.org/show_bug.cgi?id=16599Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Make "acpi_backlight=video" param enable ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO
as intended, instead of incorrectly enabling video output switching.

BugLink: http://bugs.launchpad.net/bugs/573120Signed-off-by: NKamal Mostafa <kamal@canonical.com>
Acked-by: NZhang Rui <rui.zhang@intel.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: <stable@kernel.org>
Acked-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

fix some typos and punctuation in comments
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The existing interface only has a pre-order callback. This change
adds an additional parameter for a post-order callback which will
be more useful for bus scans. ACPICA BZ 779.

Also update the external calls to acpi_walk_namespace.

http://www.acpica.org/bugzilla/show_bug.cgi?id=779Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

BugLink: http://bugs.launchpad.net/bugs/333386

Currently a video bus device must (beside other criteria) define _DOD and
_DOS methods to be considered a video device.
Some broken BIOSes prevented working backlight control by only defining both
for one (non-existing bus) and only _DOD for the rest. With this patch in
place the other bus definitions were considered too and backlight control
started to work again.
Signed-off-by: NStefan Bader <stefan.bader@canonical.com>
Acked-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Linux/ACPI core files using internal.h all PREFIX "ACPI: ",
however, not all ACPI drivers use/want it -- and they
should not have to #undef PREFIX to define their own.

Add GPL commment to internal.h while we are there.

This does not change any actual console output,
asside from a whitespace fix.
Signed-off-by: NLen Brown <len.brown@intel.com>

Now that acpi_get_pci_dev is available, let's use it instead of
acpi_get_physical_pci_device()

Cc: Thomas Renninger <trenn@suse.de>
Signed-off-by: NAlex Chiang <achiang@hp.com>
Acked-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

ACPI backlight control w/o _BQC support is kinda firmware bug.
Add a warning if _BQC is not implemented.
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Sparse asked whether these could be static.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

If an ACPI graphics device supports backlight brightness functions (cmp. with
latest ACPI spec Appendix B), let the ACPI video driver control backlight and
switch backlight control off in vendor specific ACPI drivers (asus_acpi,
thinkpad_acpi, eeepc, fujitsu_laptop, msi_laptop, sony_laptop, acer-wmi).

Currently it is possible to load above drivers and let both poke on the
brightness HW registers, the video and vendor specific ACPI drivers -> bad.

This patch provides the basic support to check for BIOS capabilities before
driver loading time. Driver specific modifications are in separate follow up
patches.

"acpi_backlight=vendor"
	Prever vendor driver over ACPI driver for backlight.
"acpi_backlight=video" (default)
	Prever ACPI driver over vendor driver for backlight.
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>