linux-toradex.git/drivers/acpi/acpi_video.c, branch v6.11

ACPI: video: Use strscpy() instead of strcpy()

2024-07-04T12:21:37+00:00

Replace strcpy() with strscpy() in the ACPI backlight code.

strcpy() has been deprecated because it is generally unsafe, so help to
eliminate if from the kernel source.

Link: https://github.com/KSPP/linux/issues/88
Signed-off-by: Muhammad Qasim Abdul Majeed 
Link: https://patch.msgid.link/20240703084124.11530-1-qasim.majeed20@gmail.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki

ACPI: video: Handle fetching EDID that is longer than 256 bytes

2024-02-08T13:03:47+00:00

The ACPI specification allows for an EDID to be up to 512 bytes but
the _DDC EDID fetching code will only try up to 256 bytes.

Modify the code to instead start at 512 bytes and work it's way
down instead.

As _DDC is now called up to 4 times on a machine debugging messages
are noisier than necessary.  Decrease from info to debug.

Link: https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/Apx_B_Video_Extensions/output-device-specific-methods.html#ddc-return-the-edid-for-this-device
Signed-off-by: Mario Limonciello 
[ rjw: Type mismatch fix, minor whitespace adjustment ]
Signed-off-by: Rafael J. Wysocki

ACPI: video: Add quirk for the Colorful X15 AT 23 Laptop

2023-12-06T19:59:49+00:00

The Colorful X15 AT 23 ACPI video-bus device report spurious
ACPI_VIDEO_NOTIFY_CYCLE events resulting in spurious KEY_SWITCHVIDEOMODE
events being reported to userspace (and causing trouble there) when
an external screen plugged in.

Add a quirk setting the report_key_events mask to
REPORT_BRIGHTNESS_KEY_EVENTS so that the ACPI_VIDEO_NOTIFY_CYCLE
events will be ignored, while still reporting brightness up/down
hotkey-presses to userspace normally.

Signed-off-by: Yuluo Qiu 
Co-developed-by: Celeste Liu 
Signed-off-by: Celeste Liu 
Signed-off-by: Rafael J. Wysocki

Merge back earlier ACPI backlight driver changes for v6.8.

2023-12-02T14:19:53+00:00

ACPI: video: Use acpi_video_device for cooling-dev driver data

2023-11-27T20:05:03+00:00

The acpi_video code was storing the acpi_video_device as driver_data
in the acpi_device children of the acpi_video_bus acpi_device.

But the acpi_video driver only binds to the bus acpi_device.
It uses, but does not bind to, the children. Since it is not
the driver it should not be using the driver_data of the children's
acpi_device-s.

Since commit 0d16710146a1 ("ACPI: bus: Set driver_data to NULL every
time .add() fails") the childen's driver_data ends up getting set
to NULL after a driver fails to bind to the children leading to a NULL
pointer deref in video_get_max_state when registering the cooling-dev:

[    3.148958] BUG: kernel NULL pointer dereference, address: 0000000000000090

[    3.149015] Hardware name: Sony Corporation VPCSB2X9R/VAIO, BIOS R2087H4 06/15/2012
[    3.149021] RIP: 0010:video_get_max_state+0x17/0x30 [video]

[    3.149105] Call Trace:
[    3.149110]  
[    3.149114]  ? __die+0x23/0x70
[    3.149126]  ? page_fault_oops+0x171/0x4e0
[    3.149137]  ? exc_page_fault+0x7f/0x180
[    3.149147]  ? asm_exc_page_fault+0x26/0x30
[    3.149158]  ? video_get_max_state+0x17/0x30 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[    3.149176]  ? __pfx_video_get_max_state+0x10/0x10 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[    3.149192]  __thermal_cooling_device_register.part.0+0xf2/0x2f0
[    3.149205]  acpi_video_bus_register_backlight.part.0.isra.0+0x414/0x570 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[    3.149227]  acpi_video_register_backlight+0x57/0x80 [video 9b6f3f0d19d7b4a0e2df17a2d8b43bc19c2ed71f]
[    3.149245]  intel_acpi_video_register+0x68/0x90 [i915 1f3a758130b32ef13d301d4f8f78c7d766d57f2a]
[    3.149669]  intel_display_driver_register+0x28/0x50 [i915 1f3a758130b32ef13d301d4f8f78c7d766d57f2a]
[    3.150064]  i915_driver_probe+0x790/0xb90 [i915 1f3a758130b32ef13d301d4f8f78c7d766d57f2a]
[    3.150402]  local_pci_probe+0x45/0xa0
[    3.150412]  pci_device_probe+0xc1/0x260


Fix this by directly using the acpi_video_device as devdata for
the cooling-device, which avoids the need to set driver-data on
the children at all.

Fixes: 0d16710146a1 ("ACPI: bus: Set driver_data to NULL every time .add() fails")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9718
Cc: 6.6+  # 6.6+
Signed-off-by: Hans de Goede 
Signed-off-by: Rafael J. Wysocki

ACPI: video: check for error while searching for backlight device parent

2023-11-21T19:47:05+00:00

If acpi_get_parent() called in acpi_video_dev_register_backlight()
fails, for example, because acpi_ut_acquire_mutex() fails inside
acpi_get_parent), this can lead to incorrect (uninitialized)
acpi_parent handle being passed to acpi_get_pci_dev() for detecting
the parent pci device.

Check acpi_get_parent() result and set parent device only in case of success.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 9661e92c10a9 ("acpi: tie ACPI backlight devices to PCI devices if possible")
Signed-off-by: Nikita Kiryushin 
Signed-off-by: Rafael J. Wysocki

ACPI: video: Drop should_check_lcd_flag()

2023-11-20T16:49:03+00:00

Since commit 3dbc80a3e4c5 ("ACPI: video: Make backlight class device
registration a separate step (v2)") acpi_video# backlights are no longer
automatically registered. Instead they now only get registered when
the GPU/KMS driver calls acpi_video_register_backlight() which it only
does when it has detected an internal LCD panel.

This fixes the issue of sometimes a non-working acpi_video# backlight
showing up on Desktops / HDMI-sticks without an internal LCD display
in a more complete and robust manner then the LCD flag check which
gets enabled by the should_check_lcd_flag() helper does.

Therefor the should_check_lcd_flag() helper is no longer necessary.

The lcd_only flag itself is still necessary to only register
a single backlight device (for the right output) on the ESPRIMO Mobile
M9410 which has 2 ACPI video connector nodes with a _BCM control method,
which is the issue for which the flag was originally introduced in
commit e50b9be14ab0 ("ACPI / video: only register backlight for LCD
device").

Signed-off-by: Hans de Goede 
Signed-off-by: Rafael J. Wysocki

ACPI: video: Use acpi_device_fix_up_power_children()

2023-11-20T16:31:49+00:00

Commit 89c290ea7589 ("ACPI: video: Put ACPI video and its child devices
into D0 on boot") introduced calling acpi_device_fix_up_power_extended()
on the video card for which the ACPI video bus is the companion device.

This unnecessarily touches the power-state of the GPU itself, while
the issue it tries to address only requires calling _PS0 on the child
devices.

Touching the power-state of the GPU itself is causing suspend / resume
issues on e.g. a Lenovo ThinkPad W530.

Instead use acpi_device_fix_up_power_children(), which only touches
the child devices, to fix this.

Fixes: 89c290ea7589 ("ACPI: video: Put ACPI video and its child devices into D0 on boot")
Reported-by: Owen T. Heisler 
Closes: https://lore.kernel.org/regressions/9f36fb06-64c4-4264-aaeb-4e1289e764c4@owenh.net/
Closes: https://gitlab.freedesktop.org/drm/nouveau/-/issues/273
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218124
Tested-by: Kai-Heng Feng 
Tested-by: Owen T. Heisler 
Signed-off-by: Hans de Goede 
Cc: 6.6+  # 6.6+
Signed-off-by: Rafael J. Wysocki

ACPI: bus: Add context argument to acpi_dev_install_notify_handler()

2023-10-06T15:32:51+00:00

Add void *context arrgument to the list of arguments of
acpi_dev_install_notify_handler() and modify it to pass that argument
as context to acpi_install_notify_handler() instead of its first
argument which is problematic in general (for example, if platform
drivers used it, they would rather get struct platform_device pointers
or pointers to their private data from the context arguments of their
notify handlers).

Make all of the current callers of acpi_dev_install_notify_handler()
take this change into account so as to avoid altering the general
functionality.

Co-developed-by: Michal Wilczynski 
Signed-off-by: Michal Wilczynski 
Signed-off-by: Rafael J. Wysocki

ACPI: video: Fix NULL pointer dereference in acpi_video_bus_add()

2023-09-25T09:53:40+00:00

acpi_video_bus_add_notify_handler() could free video->input and
set it to NULL on failure, but this failure would be missed in its
caller acpi_video_bus_add(). As a result, when an error happens in
acpi_dev_install_notify_handler(), acpi_video_bus_add() would call
acpi_video_bus_remove_notify_handler(), where a potential NULL pointer
video->input is dereferenced in input_unregister_device().

Fix this by adding a return value check and adjusting the following
error handling code.

Fixes: 6f7016819766 ("ACPI: video: Install Notify() handler directly")
Signed-off-by: Dinghao Liu 
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki