Re: [PATCH 00/22] Fallback to native backlight

From: Hans de Goede
Date: Mon Oct 24 2022 - 19:29:27 EST


Hi,

On 10/24/22 13:56, Akihiko Odaki wrote:
> On 2022/10/24 20:48, Jani Nikula wrote:
>> On Mon, 24 Oct 2022, Akihiko Odaki <akihiko.odaki@xxxxxxxxxx> wrote:
>>> Commit 2600bfa3df99 ("ACPI: video: Add acpi_video_backlight_use_native()
>>> helper") and following commits made native backlight unavailable if
>>> CONFIG_ACPI_VIDEO is set and the backlight feature of ACPI video is
>>> unavailable, which broke the backlight functionality on Lenovo ThinkPad
>>> C13 Yoga Chromebook. Allow to fall back to native backlight in such
>>> cases.
>>
>> Where's the bug report with relevant logs, kconfigs, etc?
>
> I haven't filed one. Should I? Please tell me where to report and what information you would need (to bugzilla.kernel.org with things mentioned in Documentation/admin-guide/reporting-issues.rst?)

As mentioned in my other email this is a known issue, and your effort
to fix this is appreciated very much, but I don't believe your solution
to be the right one.

See: https://lore.kernel.org/linux-acpi/42a5f2c9-a1dc-8fc0-7334-fe6c390ecfbb@xxxxxxxxxx/
for more details and possible solutions. Please try implementing one of
those solutions for your Chromebook. I unfortunately do not have hw to
test this myself.

Regards,

Hans



>
> Regards,
> Akihiko Odaki
>
>>
>> BR,
>> Jani.
>>
>>>
>>> Signed-off-by: Akihiko Odaki <akihiko.odaki@xxxxxxxxxx>
>>>
>>> Akihiko Odaki (22):
>>>    drm/i915/opregion: Improve backlight request condition
>>>    ACPI: video: Introduce acpi_video_get_backlight_types()
>>>    LoongArch: Use acpi_video_get_backlight_types()
>>>    platform/x86: acer-wmi: Use acpi_video_get_backlight_types()
>>>    platform/x86: asus-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: asus-wmi: Use acpi_video_get_backlight_types()
>>>    platform/x86: compal-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: eeepc-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: fujitsu-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: ideapad-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: msi-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: msi-wmi: Use acpi_video_get_backlight_types()
>>>    platform/x86: nvidia-wmi-ec-backlight: Use
>>>      acpi_video_get_backlight_types()
>>>    platform/x86: panasonic-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: samsung-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: sony-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: thinkpad_acpi: Use acpi_video_get_backlight_types()
>>>    platform/x86: toshiba_acpi: Use acpi_video_get_backlight_types()
>>>    platform/x86: dell-laptop: Use acpi_video_get_backlight_types()
>>>    platform/x86: intel_oaktrail: Use acpi_video_get_backlight_types()
>>>    ACPI: video: Remove acpi_video_get_backlight_type()
>>>    ACPI: video: Fallback to native backlight
>>>
>>>   Documentation/gpu/todo.rst                    |  8 +--
>>>   drivers/acpi/acpi_video.c                     |  2 +-
>>>   drivers/acpi/video_detect.c                   | 54 ++++++++++---------
>>>   drivers/gpu/drm/i915/display/intel_opregion.c |  3 +-
>>>   drivers/platform/loongarch/loongson-laptop.c  |  4 +-
>>>   drivers/platform/x86/acer-wmi.c               |  2 +-
>>>   drivers/platform/x86/asus-laptop.c            |  2 +-
>>>   drivers/platform/x86/asus-wmi.c               |  4 +-
>>>   drivers/platform/x86/compal-laptop.c          |  2 +-
>>>   drivers/platform/x86/dell/dell-laptop.c       |  2 +-
>>>   drivers/platform/x86/eeepc-laptop.c           |  2 +-
>>>   drivers/platform/x86/fujitsu-laptop.c         |  4 +-
>>>   drivers/platform/x86/ideapad-laptop.c         |  2 +-
>>>   drivers/platform/x86/intel/oaktrail.c         |  2 +-
>>>   drivers/platform/x86/msi-laptop.c             |  2 +-
>>>   drivers/platform/x86/msi-wmi.c                |  2 +-
>>>   .../platform/x86/nvidia-wmi-ec-backlight.c    |  2 +-
>>>   drivers/platform/x86/panasonic-laptop.c       |  2 +-
>>>   drivers/platform/x86/samsung-laptop.c         |  2 +-
>>>   drivers/platform/x86/sony-laptop.c            |  2 +-
>>>   drivers/platform/x86/thinkpad_acpi.c          |  4 +-
>>>   drivers/platform/x86/toshiba_acpi.c           |  2 +-
>>>   drivers/video/backlight/backlight.c           | 18 +++++++
>>>   include/acpi/video.h                          | 21 ++++----
>>>   include/linux/backlight.h                     |  1 +
>>>   25 files changed, 85 insertions(+), 66 deletions(-)
>>
>