linux-stable/include/acpi
Hans de Goede 0bb6742bf8 ACPI: Fix selecting wrong ACPI fwnode for the iGPU on some Dell laptops
commit f64e4275ef upstream.

The Dell Latitude E6430 both with and without the optional NVidia dGPU
has a bug in its ACPI tables which is causing Linux to assign the wrong
ACPI fwnode / companion to the pci_device for the i915 iGPU.

Specifically under the PCI root bridge there are these 2 ACPI Device()s :

 Scope (_SB.PCI0)
 {
     Device (GFX0)
     {
         Name (_ADR, 0x00020000)  // _ADR: Address
     }

     ...

     Device (VID)
     {
         Name (_ADR, 0x00020000)  // _ADR: Address
         ...

         Method (_DOS, 1, NotSerialized)  // _DOS: Disable Output Switching
         {
             VDP8 = Arg0
             VDP1 (One, VDP8)
         }

         Method (_DOD, 0, NotSerialized)  // _DOD: Display Output Devices
         {
             ...
         }
         ...
     }
 }

The non-functional GFX0 ACPI device is a problem, because this gets
returned as ACPI companion-device by acpi_find_child_device() for the iGPU.

This is a long standing problem and the i915 driver does use the ACPI
companion for some things, but works fine without it.

However since commit 63f534b8ba ("ACPI: PCI: Rework acpi_get_pci_dev()")
acpi_get_pci_dev() relies on the physical-node pointer in the acpi_device
and that is set on the wrong acpi_device because of the wrong
acpi_find_child_device() return. This breaks the ACPI video code,
leading to non working backlight control in some cases.

Add a type.backlight flag, mark ACPI video bus devices with this and make
find_child_checks() return a higher score for children with this flag set,
so that it picks the right companion-device.

Fixes: 63f534b8ba ("ACPI: PCI: Rework acpi_get_pci_dev()")
Co-developed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: 6.1+ <stable@vger.kernel.org> # 6.1+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:58:11 +01:00
..
platform ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acbuffer.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acconfig.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acexcep.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acnames.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acoutput.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acpi.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acpi_bus.h ACPI: Fix selecting wrong ACPI fwnode for the iGPU on some Dell laptops 2023-01-18 11:58:11 +01:00
acpi_drivers.h Merge branches 'acpi-pci' and 'acpi-processor' 2021-04-26 17:03:05 +02:00
acpi_io.h Revert "ACPI: Add memory semantics to acpi_os_map_memory()" 2021-09-23 20:39:36 +02:00
acpi_lpat.h
acpi_numa.h ACPI: processor: Replace kernel.h with the necessary inclusions 2021-11-24 17:44:04 +01:00
acpiosxf.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
acpixf.h ACPICA: Update version to 20220331 2022-04-13 20:24:58 +02:00
acrestyp.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
actbl.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
actbl1.h ACPICA: Removed some tabs and // comments 2022-04-13 20:24:57 +02:00
actbl2.h ACPICA: IORT: Updates for revision E.d 2022-04-13 20:24:58 +02:00
actbl3.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
actypes.h ACPICA: Removed some tabs and // comments 2022-04-13 20:24:57 +02:00
acuuid.h ACPICA: Update copyright notices to the year 2022 2022-04-13 20:24:57 +02:00
apei.h ACPI: APEI: Fix missing ERST record id 2022-04-13 20:29:24 +02:00
battery.h ACPI: battery: include linux/power_supply.h 2020-09-25 18:31:19 +02:00
button.h
cppc_acpi.h ACPI: CPPC: Disable FIE if registers in PCC regions 2022-09-24 18:43:46 +02:00
ghes.h ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init() 2022-10-13 20:40:09 +02:00
hed.h
nfit.h
pcc.h mailbox: pcc: Use PCC mailbox channel pointer instead of standard 2021-10-29 22:46:38 -05:00
pdc_intel.h
processor.h ACPI: processor: Drop leftover acpi_processor_get_limit_info() declaration 2022-06-29 19:01:23 +02:00
reboot.h
video.h ACPI: video: Allow GPU drivers to report no panels 2023-01-12 12:02:39 +01:00