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João Paulo Rechi Vita e5090418fb platform/x86: asus-wmi: Tell the EC the OS will handle the display off hotkey
[ Upstream commit 78f3ac76d9 ]

In the past, Asus firmwares would change the panel backlight directly
through the EC when the display off hotkey (Fn+F7) was pressed, and
only notify the OS of such change, with 0x33 when the LCD was ON and
0x34 when the LCD was OFF. These are currently mapped to
KEY_DISPLAYTOGGLE and KEY_DISPLAY_OFF, respectively.

Most recently the EC on Asus most machines lost ability to toggle the
LCD backlight directly, but unless the OS informs the firmware it is
going to handle the display toggle hotkey events, the firmware still
tries change the brightness through the EC, to no effect. The end result
is a long list (at Endless we counted 11) of Asus laptop models where
the display toggle hotkey does not perform any action. Our firmware
engineers contacts at Asus were surprised that there were still machines
out there with the old behavior.

Calling WMNB(ASUS_WMI_DEVID_BACKLIGHT==0x00050011, 2) on the _WDG device
tells the firmware that it should let the OS handle the display toggle
event, in which case it will simply notify the OS of a key press with
0x35, as shown by the DSDT excerpts bellow.

 Scope (_SB)
 {
     (...)

     Device (ATKD)
     {
         (...)

         Name (_WDG, Buffer (0x28)
         {
             /* 0000 */  0xD0, 0x5E, 0x84, 0x97, 0x6D, 0x4E, 0xDE, 0x11,
             /* 0008 */  0x8A, 0x39, 0x08, 0x00, 0x20, 0x0C, 0x9A, 0x66,
             /* 0010 */  0x4E, 0x42, 0x01, 0x02, 0x35, 0xBB, 0x3C, 0x0B,
             /* 0018 */  0xC2, 0xE3, 0xED, 0x45, 0x91, 0xC2, 0x4C, 0x5A,
             /* 0020 */  0x6D, 0x19, 0x5D, 0x1C, 0xFF, 0x00, 0x01, 0x08
         })
         Method (WMNB, 3, Serialized)
         {
             CreateDWordField (Arg2, Zero, IIA0)
             CreateDWordField (Arg2, 0x04, IIA1)
             Local0 = (Arg1 & 0xFFFFFFFF)

             (...)

             If ((Local0 == 0x53564544))
             {
                 (...)

                 If ((IIA0 == 0x00050011))
                 {
                     If ((IIA1 == 0x02))
                     {
                         ^^PCI0.SBRG.EC0.SPIN (0x72, One)
                         ^^PCI0.SBRG.EC0.BLCT = One
                     }

                     Return (One)
                 }
             }
             (...)
         }
         (...)
     }
     (...)
 }
 (...)

 Scope (_SB.PCI0.SBRG.EC0)
 {
     (...)

     Name (BLCT, Zero)

     (...)

     Method (_Q10, 0, NotSerialized)  // _Qxx: EC Query
     {
         If ((BLCT == Zero))
         {
             Local0 = One
             Local0 = RPIN (0x72)
             Local0 ^= One
             SPIN (0x72, Local0)
             If (ATKP)
             {
                 Local0 = (0x34 - Local0)
                 ^^^^ATKD.IANE (Local0)
             }
         }
         ElseIf ((BLCT == One))
         {
             If (ATKP)
             {
                 ^^^^ATKD.IANE (0x35)
             }
         }
     }
     (...)
 }

Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:34 +01:00
arch Disable MSI also when pcie-octeon.pcie_disable on 2019-01-22 21:40:34 +01:00
block block: use rcu_work instead of call_rcu to avoid sleep in softirq 2019-01-22 21:40:35 +01:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: authenc - fix parsing key with misaligned rta_len 2019-01-22 21:40:32 +01:00
Documentation x86/speculation/l1tf: Drop the swap storage limit restriction when l1tf=off 2019-01-09 17:38:41 +01:00
drivers platform/x86: asus-wmi: Tell the EC the OS will handle the display off hotkey 2019-01-26 09:32:34 +01:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs blockdev: Fix livelocks on loop device 2019-01-22 21:40:36 +01:00
include block: use rcu_work instead of call_rcu to avoid sleep in softirq 2019-01-22 21:40:35 +01:00
init kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7 2019-01-22 21:40:34 +01:00
ipc ipc/shm.c: use ERR_CAST() for shm_lock() error return 2018-10-05 16:32:04 -07:00
kernel sched/fair: Fix infinite loop in update_blocked_averages() by reverting a9e7f6544b 2019-01-13 09:51:09 +01:00
lib fix int_sqrt64() for very large numbers 2019-01-22 21:40:34 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: page_mapped: don't assume compound page is huge or THP 2019-01-16 22:04:36 +01:00
net netfilter: ipset: Allow matching on destination MAC address for mac and ipmac sets 2019-01-26 09:32:33 +01:00
samples samples: disable CONFIG_SAMPLES for UML 2018-10-11 02:15:46 +09:00
scripts x86, modpost: Replace last remnants of RETPOLINE with CONFIG_RETPOLINE 2019-01-16 22:04:29 +01:00
security selinux: fix GPF on invalid policy 2019-01-22 21:40:35 +01:00
sound ALSA: hda/realtek - Disable headset Mic VREF for headset mode of ALC225 2019-01-16 22:04:30 +01:00
tools selftests: Fix test errors related to lib.mk khdr target 2019-01-22 21:40:38 +01:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: arm/arm64: Fix VMID alloc race by reverting to lock-less 2019-01-16 22:04:37 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Add Sasha as a stable branch maintainer 2018-12-01 09:37:25 +01:00
Makefile Linux 4.19.17 2019-01-22 21:40:38 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.